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Sample records for analyzing connectivity patterns

  1. Visualizing neuronal network connectivity with connectivity pattern tables

    Directory of Open Access Journals (Sweden)

    Eilen Nordlie

    2010-01-01

    Full Text Available Complex ideas are best conveyed through well-designed illustrations. Up to now, computational neuroscientists have mostly relied on box-and-arrow diagrams of even complex neuronal networks, often using ad hoc notations with conflicting use of symbols from paper to paper. This significantly impedes the communication of ideas in neuronal network modeling. We present here Connectivity Pattern Tables (CPTs as a clutter-free visualization of connectivity in large neuronal networks containing two-dimensional populations of neurons. CPTs can be generated automatically from the same script code used to create the actual network in the NEST simulator. Through aggregation, CPTs can be viewed at different levels, providing either full detail or summary information. We also provide the open source ConnPlotter tool as a means to create connectivity pattern tables.

  2. Analyzing Sequential Patterns in Retail Databases

    Institute of Scientific and Technical Information of China (English)

    Unil Yun

    2007-01-01

    Finding correlated sequential patterns in large sequence databases is one of the essential tasks in data miningsince a huge number of sequential patterns are usually mined, but it is hard to find sequential patterns with the correlation.According to the requirement of real applications, the needed data analysis should be different. In previous mining approaches,after mining the sequential patterns, sequential patterns with the weak affinity are found even with a high minimum support.In this paper, a new framework is suggested for mining weighted support affinity patterns in which an objective measure,sequential ws-confidence is developed to detect correlated sequential patterns with weighted support affinity patterns. Toefficiently prune the weak affinity patterns, it is proved that ws-confidence measure satisfies the anti-monotone and crossweighted support properties which can be applied to eliminate sequential patterns with dissimilar weighted support levels.Based on the framework, a weighted support affinity pattern mining algorithm (WSMiner) is suggested. The performancestudy shows that WSMiner is efficient and scalable for mining weighted support affinity patterns.

  3. Seismic entangled patterns analyzed via multiresolution decomposition

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    F. E. A. Leite

    2009-03-01

    Full Text Available This article explores a method for distinguishing entangled coherent structures embedded in geophysical images. The original image is decomposed in a series of j-scale-images using multiresolution decomposition. To improve the image processing analysis each j-image is divided in l-spacial regions generating set of (j, l-regions. At each (j, l-region we apply a continuous wavelet transform to evaluate Eν, the spectrum of energy. Eν has two maxima in the original data. Otherwise, at each scale Eν hast typically one peak. The localization of the peaks changes according to the (j, l-region. The intensity of the peaks is linked with the presence of coherent structures, or patterns, at the respective (j, l-region. The method is successfully applied to distinguish, in scale and region, the ground roll noise from the relevant geologic information in the signal.

  4. Pattern Genes Suggest Functional Connectivity of Organs

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    Qin, Yangmei; Pan, Jianbo; Cai, Meichun; Yao, Lixia; Ji, Zhiliang

    2016-05-01

    Human organ, as the basic structural and functional unit in human body, is made of a large community of different cell types that organically bound together. Each organ usually exerts highly specified physiological function; while several related organs work smartly together to perform complicated body functions. In this study, we present a computational effort to understand the roles of genes in building functional connection between organs. More specifically, we mined multiple transcriptome datasets sampled from 36 human organs and tissues, and quantitatively identified 3,149 genes whose expressions showed consensus modularly patterns: specific to one organ/tissue, selectively expressed in several functionally related tissues and ubiquitously expressed. These pattern genes imply intrinsic connections between organs. According to the expression abundance of the 766 selective genes, we consistently cluster the 36 human organs/tissues into seven functional groups: adipose & gland, brain, muscle, immune, metabolism, mucoid and nerve conduction. The organs and tissues in each group either work together to form organ systems or coordinate to perform particular body functions. The particular roles of specific genes and selective genes suggest that they could not only be used to mechanistically explore organ functions, but also be designed for selective biomarkers and therapeutic targets.

  5. Analyzing and Assessing Brain Structure with Graph Connectivity Measures

    Science.gov (United States)

    2014-05-09

    here. We implement several connectiv - ity measures used in previous studies which used networks to analyze brain structure in order to reproduce results... connectiv - ity measures. In response, we implemented a breadth first search algorithm which examined unconnected networks and found the largest

  6. Lexical Connection: Semiterm Grammatical Patterns in Spanish

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    Ferrero, Carmen Lopez

    2012-01-01

    The aim of this article is to describe the grammatical patterns of a set of nouns frequently used in Spanish specialized discourse: the so-called "semiterms". The following nouns were selected for the study: "problema" "problem", "resultado" "result", "motivo" "motive/reason", "razon" "reason", and "consecuencia" "consequence". Apart from…

  7. The Repeat Pattern Toolkit (RPT): Analyzing the structure and evolution of the C. elegans genome

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    Agarwal, P.; States, D.J. [Washington Univ., St. Louis, MO (United States)

    1994-12-31

    Over 3.6 million bases of DNA sequence from chromosome III of the C. elegans have been determined. The availability of this extended region of contiguous sequence has allowed us to analyze the nature and prevalence of repetitive sequences in the genome of a eukaryotic organism with a high gene density. We have assembled a Repeat Pattern Toolkit (RPT) to analyze the patterns of repeats occurring in DNA. The tools include identifying significant local alignments (utilizing both two-way and three-way alignments), dividing the set of alignments into connected components (signifying repeat families), computing evolutionary distance between repeat family members, constructing minimum spanning trees from the connected components, and visualizing the evolution of the repeat families. Over 7000 families of repetitive sequences were identified. The size of the families ranged from isolated pairs to over 1600 segments of similar sequence. Approximately 12.3% of the analyzed sequence participates in a repeat element.

  8. Capturing and analyzing wheelchair maneuvering patterns with mobile cloud computing.

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    Fu, Jicheng; Hao, Wei; White, Travis; Yan, Yuqing; Jones, Maria; Jan, Yih-Kuen

    2013-01-01

    Power wheelchairs have been widely used to provide independent mobility to people with disabilities. Despite great advancements in power wheelchair technology, research shows that wheelchair related accidents occur frequently. To ensure safe maneuverability, capturing wheelchair maneuvering patterns is fundamental to enable other research, such as safe robotic assistance for wheelchair users. In this study, we propose to record, store, and analyze wheelchair maneuvering data by means of mobile cloud computing. Specifically, the accelerometer and gyroscope sensors in smart phones are used to record wheelchair maneuvering data in real-time. Then, the recorded data are periodically transmitted to the cloud for storage and analysis. The analyzed results are then made available to various types of users, such as mobile phone users, traditional desktop users, etc. The combination of mobile computing and cloud computing leverages the advantages of both techniques and extends the smart phone's capabilities of computing and data storage via the Internet. We performed a case study to implement the mobile cloud computing framework using Android smart phones and Google App Engine, a popular cloud computing platform. Experimental results demonstrated the feasibility of the proposed mobile cloud computing framework.

  9. Short local descriptors from 2D connected pattern spectra

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    Bosilj, Petra; Kijak, Ewa; Wilkinson, Michael H. F.; Lefèvre, Sebastien

    2015-01-01

    We propose a local region descriptor based on connected pattern spectra, and combined with normalized central moments. The descriptors are calculated for MSER regions of the image, and their performance compared against SIFT. The MSER regions were chosen because they can be efficiently selected by c

  10. Pattern reverberation in networks of excitable systems with connection delays

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    Lücken, Leonhard; Rosin, David P.; Worlitzer, Vasco M.; Yanchuk, Serhiy

    2017-01-01

    We consider the recurrent pulse-coupled networks of excitable elements with delayed connections, which are inspired by the biological neural networks. If the delays are tuned appropriately, the network can either stay in the steady resting state, or alternatively, exhibit a desired spiking pattern. It is shown that such a network can be used as a pattern-recognition system. More specifically, the application of the correct pattern as an external input to the network leads to a self-sustained reverberation of the encoded pattern. In terms of the coupling structure, the tolerance and the refractory time of the individual systems, we determine the conditions for the uniqueness of the sustained activity, i.e., for the functionality of the network as an unambiguous pattern detector. We point out the relation of the considered systems with cyclic polychronous groups and show how the assumed delay configurations may arise in a self-organized manner when a spike-time dependent plasticity of the connection delays is assumed. As excitable elements, we employ the simplistic coincidence detector models as well as the Hodgkin-Huxley neuron models. Moreover, the system is implemented experimentally on a Field-Programmable Gate Array.

  11. Cocaine dependence and thalamic functional connectivity: a multivariate pattern analysis

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    Sheng Zhang

    2016-01-01

    Full Text Available Cocaine dependence is associated with deficits in cognitive control. Previous studies demonstrated that chronic cocaine use affects the activity and functional connectivity of the thalamus, a subcortical structure critical for cognitive functioning. However, the thalamus contains nuclei heterogeneous in functions, and it is not known how thalamic subregions contribute to cognitive dysfunctions in cocaine dependence. To address this issue, we used multivariate pattern analysis (MVPA to examine how functional connectivity of the thalamus distinguishes 100 cocaine-dependent participants (CD from 100 demographically matched healthy control individuals (HC. We characterized six task-related networks with independent component analysis of fMRI data of a stop signal task and employed MVPA to distinguish CD from HC on the basis of voxel-wise thalamic connectivity to the six independent components. In an unbiased model of distinct training and testing data, the analysis correctly classified 72% of subjects with leave-one-out cross-validation (p < 0.001, superior to comparison brain regions with similar voxel counts (p < 0.004, two-sample t test. Thalamic voxels that form the basis of classification aggregate in distinct subclusters, suggesting that connectivities of thalamic subnuclei distinguish CD from HC. Further, linear regressions provided suggestive evidence for a correlation of the thalamic connectivities with clinical variables and performance measures on the stop signal task. Together, these findings support thalamic circuit dysfunction in cognitive control as an important neural marker of cocaine dependence.

  12. Repositioning through Culture: Testing Change in Connectivity Patterns

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    Beatriz Plaza

    2016-12-01

    Full Text Available Symbolic knowledge-driven innovations can play an important role in the economic development of cities and regions. Cultural events and infrastructures can act as powerful connectivity engines, generating new connections, rewiring links, and repositioning institutions/cities/regions on the Internet map. Within this framework, this paper aims to contribute to the analytical understanding of culture-led repositioning. For this purpose we perform regression analysis with cultural networks (observational cross-sectional network data from digital media for a specific cultural case study: the Basque Culinary Center (BCC, a higher education faculty of haute cuisine promoted by the University of Mondragon along with a group of Michelin-starred chefs. Results show that a cultural sector, such as haute cuisine, can contribute to structural changes in connectivity patterns, putting an institution/city/region on the media map. It is the connection (in the online press of the BCC to the influential Michelin-starred chefs that can fuel the accumulation of press articles (media items on the BCC; and it is precisely this accumulation of press articles that can impact BCC revenues. Put differently, the co-branding between the influential Michelin chefs and the BCC may have put the BCC on the press map, promoting new student registrations and fostering Basque haute cuisine. The main contribution of this article is a prototype of regression analysis to test repositioning with network data.

  13. GUIDOS: tools for the assessment of pattern, connectivity, and fragmentation

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    Vogt, Peter

    2013-04-01

    Pattern, connectivity, and fragmentation can be considered as pillars for a quantitative analysis of digital landscape images. The free software toolbox GUIDOS (http://forest.jrc.ec.europa.eu/download/software/guidos) includes a variety of dedicated methodologies for the quantitative assessment of these features. Amongst others, Morphological Spatial Pattern Analysis (MSPA) is used for an intuitive description of image pattern structures and the automatic detection of connectivity pathways. GUIDOS includes tools for the detection and quantitative assessment of key nodes and links as well as to define connectedness in raster images and to setup appropriate input files for an enhanced network analysis using Conefor Sensinode. Finally, fragmentation is usually defined from a species point of view but a generic and quantifiable indicator is needed to measure fragmentation and its changes. Some preliminary results for different conceptual approaches will be shown for a sample dataset. Complemented by pre- and post-processing routines and a complete GIS environment the portable GUIDOS Toolbox may facilitate a holistic assessment in risk assessment studies, landscape planning, and conservation/restoration policies. Alternatively, individual analysis components may contribute to or enhance studies conducted with other software packages in landscape ecology.

  14. Convergent and divergent functional connectivity patterns in schizophrenia and depression.

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    Yang Yu

    Full Text Available Major depression and schizophrenia are two of the most serious psychiatric disorders and share similar behavioral symptoms. Whether these similar behavioral symptoms underlie any convergent psychiatric pathological mechanisms is not yet clear. To address this issue, this study sought to investigate the whole-brain resting-state functional magnetic resonance imaging (MRI of major depression and schizophrenia by using multivariate pattern analysis. Thirty-two schizophrenic patients, 19 major depressive disorder patients and 38 healthy controls underwent resting-state functional MRI scanning. A support vector machine in conjunction with intrinsic discriminant analysis was used to solve the multi-classification problem, resulting in a correct classification rate of 80.9% via leave-one-out cross-validation. The depression and schizophrenia groups both showed altered functional connections associated with the medial prefrontal cortex, anterior cingulate cortex, thalamus, hippocampus, and cerebellum. However, the prefrontal cortex, amygdala, and temporal poles were found to be affected differently by major depression and schizophrenia. Our preliminary study suggests that altered connections within or across the default mode network and the cerebellum may account for the common behavioral symptoms between major depression and schizophrenia. In addition, connections associated with the prefrontal cortex and the affective network showed promise as biomarkers for discriminating between the two disorders.

  15. Analyzing patterns in experts' approaches to solving experimental problems

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    Čančula, Maja Poklinek; Planinšič, Gorazd; Etkina, Eugenia

    2015-04-01

    We report detailed observations of three pairs of expert scientists and a pair of advanced undergraduate students solving an experimental optics problem. Using a new method ("transition graphs") of visualizing sequences of logical steps, we were able to compare the groups and identify patterns that could not be found using previously existing methods. While the problem solving of undergraduates significantly differed from that of experts at the beginning of the process, it gradually became more similar to the expert problem solving. We mapped problem solving steps and their sequence to the elements of an approach to teaching and learning physics called Investigative Science Learning Environment (ISLE), and we speculate that the ISLE educational framework closely represents the actual work of physicists.

  16. Partition-induced connections and operators for pattern analysis

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    Ouzounis, Georgios K.; Wilkinson, Michael H.F.

    2010-01-01

    In this paper we present a generalization on the notion of image connectivity similar to that modeled by second-generation connections. The connected operators based on this new type of connection make use of image partitions aided by mask images to extract path-wise connected regions that were prev

  17. Detecting altered connectivity patterns in HIV associated neurocognitive impairment using mutual connectivity analysis

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    Abidin, Anas Zainul; D'Souza, Adora M.; Nagarajan, Mahesh B.; Wismüller, Axel

    2016-03-01

    The use of functional Magnetic Resonance Imaging (fMRI) has provided interesting insights into our understanding of the brain. In clinical setups these scans have been used to detect and study changes in the brain network properties in various neurological disorders. A large percentage of subjects infected with HIV present cognitive deficits, which are known as HIV associated neurocognitive disorder (HAND). In this study we propose to use our novel technique named Mutual Connectivity Analysis (MCA) to detect differences in brain networks in subjects with and without HIV infection. Resting state functional MRI scans acquired from 10 subjects (5 HIV+ and 5 HIV-) were subject to standard preprocessing routines. Subsequently, the average time-series for each brain region of the Automated Anatomic Labeling (AAL) atlas are extracted and used with the MCA framework to obtain a graph characterizing the interactions between them. The network graphs obtained for different subjects are then compared using Network-Based Statistics (NBS), which is an approach to detect differences between graphs edges while controlling for the family-wise error rate when mass univariate testing is performed. Applying this approach on the graphs obtained yields a single network encompassing 42 nodes and 65 edges, which is significantly different between the two subject groups. Specifically connections to the regions in and around the basal ganglia are significantly decreased. Also some nodes corresponding to the posterior cingulate cortex are affected. These results are inline with our current understanding of pathophysiological mechanisms of HIV associated neurocognitive disease (HAND) and other HIV based fMRI connectivity studies. Hence, we illustrate the applicability of our novel approach with network-based statistics in a clinical case-control study to detect differences connectivity patterns.

  18. Connectivity, excitability and activity patterns in neuronal networks

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    le Feber, Joost; Stoyanova, Irina I.; Chiappalone, Michela

    2014-06-01

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

  19. External serial connection without layer patterning for organic solar cells

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    Wong, Ying Qian; Wong, Hin Yong; Tan, Ching Seong; Meng, Hsin-Fei

    2016-12-01

    This paper proposes a novel alternative to conventional internal serial connection, where precise patterning and scribing of organic layers can be eliminated. Adjacent cells can be made nearer for better space-utilization and higher voltages per unit area. Also, blade coating is proposed as the fabrication method as it has low material wastage (less than 5%), easily scalable to large area, has high film uniformity and has high throughput due to its roll-to-roll potential. This paper demonstrates 3-cells large area (12.98 cm2) external serial connection organic solar cells (OSCs) using the material poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) and 2,6-Bis(trimethyltin)-4, 8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo [1,2-b:4,5-b']dithiophene:6,6-phenyl C71-butyric acid methyl ester (PBDTTT-CT:PC71BM) respectively. The power conversion efficiencies (PCEs) of the resulting 3-cells modules are 2.0% and 4.1% respectively.

  20. Depression-Related Brain Connectivity Analyzed by EEG Event-Related Phase Synchrony Measure

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    Li, Yuezhi; Kang, Cheng; Qu, Xingda; Zhou, Yunfei; Wang, Wuyi; Hu, Yong

    2016-01-01

    This study is to examine changes of functional connectivity in patients with depressive disorder using synchronous brain activity. Event-related potentials (ERPs) were acquired during a visual oddball task in 14 patients with depressive disorder and 19 healthy controls. Electroencephalogram (EEG) recordings were analyzed using event-related phase coherence (ERPCOH) to obtain the functional network. Alteration of the phase synchronization index (PSI) of the functional network was investigated. Patients with depression showed a decreased number of significant electrode pairs in delta phase synchronization, and an increased number of significant electrode pairs in theta, alpha and beta phase synchronization, compared with controls. Patients with depression showed lower target-dependent PSI increment in the frontal-parietal/temporal/occipital electrode pairs in delta-phase synchronization than healthy participants. However, patients with depression showed higher target-dependent PSI increments in theta band in the prefrontal/frontal and frontal-temporal electrode pairs, higher PSI increments in alpha band in the prefrontal pairs and higher increments of beta PSI in the central and right frontal-parietal pairs than controls. It implied that the decrease in delta PSI activity in major depression may indicate impairment of the connection between the frontal and parietal/temporal/occipital regions. The increase in theta, alpha and beta PSI in the frontal/prefrontal sites might reflect the compensatory mechanism to maintain normal cognitive performance. These findings may provide a foundation for a new approach to evaluate the effectiveness of therapeutic strategies for depression. PMID:27725797

  1. Informational connectivity: identifying synchronized discriminability of multi-voxel patterns across the brain.

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    Coutanche, Marc N; Thompson-Schill, Sharon L

    2013-01-01

    The fluctuations in a brain region's activation levels over a functional magnetic resonance imaging (fMRI) time-course are used in functional connectivity (FC) to identify networks with synchronous responses. It is increasingly recognized that multi-voxel activity patterns contain information that cannot be extracted from univariate activation levels. Here we present a novel analysis method that quantifies regions' synchrony in multi-voxel activity pattern discriminability, rather than univariate activation, across a timeseries. We introduce a measure of multi-voxel pattern discriminability at each time-point, which is then used to identify regions that share synchronous time-courses of condition-specific multi-voxel information. This method has the sensitivity and access to distributed information that multi-voxel pattern analysis enjoys, allowing it to be applied to data from conditions not separable by univariate responses. We demonstrate this by analyzing data collected while people viewed four different types of man-made objects (typically not separable by univariate analyses) using both FC and informational connectivity (IC) methods. IC reveals networks of object-processing regions that are not detectable using FC. The IC results support prior findings and hypotheses about object processing. This new method allows investigators to ask questions that are not addressable through typical FC, just as multi-voxel pattern analysis (MVPA) has added new research avenues to those addressable with the general linear model (GLM).

  2. Analyzing the association between functional connectivity of the brain and intellectual performance.

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    Pamplona, Gustavo S P; Santos Neto, Gérson S; Rosset, Sara R E; Rogers, Baxter P; Salmon, Carlos E G

    2015-01-01

    Measurements of functional connectivity support the hypothesis that the brain is composed of distinct networks with anatomically separated nodes but common functionality. A few studies have suggested that intellectual performance may be associated with greater functional connectivity in the fronto-parietal network and enhanced global efficiency. In this fMRI study, we performed an exploratory analysis of the relationship between the brain's functional connectivity and intelligence scores derived from the Portuguese language version of the Wechsler Adult Intelligence Scale (WAIS-III) in a sample of 29 people, born and raised in Brazil. We examined functional connectivity between 82 regions, including graph theoretic properties of the overall network. Some previous findings were extended to the Portuguese-speaking population, specifically the presence of small-world organization of the brain and relationships of intelligence with connectivity of frontal, pre-central, parietal, occipital, fusiform and supramarginal gyrus, and caudate nucleus. Verbal comprehension was associated with global network efficiency, a new finding.

  3. Analyzing the association between functional connectivity of the brain and intellectual performance

    Directory of Open Access Journals (Sweden)

    Gustavo Santo Pedro Pamplona

    2015-02-01

    Full Text Available Measurements of functional connectivity support the hypothesis that the brain is composed of distinct networks with anatomically separated nodes but common functionality. A few studies have suggested that intellectual performance may be associated with greater functional connectivity in the fronto-parietal network and enhanced global efficiency. In this fMRI study, we performed an exploratory analysis of the relationship between the brain's functional connectivity and intelligence scores derived from the Portuguese language version of the Wechsler Adult Intelligence Scale (WAIS-III in a sample of 29 people, born and raised in Brazil. We examined functional connectivity between 82 regions, including graph theoretic properties of the overall network. Some previous findings were extended to the Portuguese-speaking population, specifically the presence of small-world organization of the brain and relationships of intelligence with connectivity of frontal, pre-central, parietal, occipital, fusiform and supramarginal gyrus and caudate nucleus. Verbal comprehension was associated with global network efficiency, a new finding.

  4. Analyzing the scaling of connectivity in neuromorphic hardware and in models of neural networks.

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    Partzsch, Johannes; Schüffny, René

    2011-06-01

    In recent years, neuromorphic hardware systems have significantly grown in size. With more and more neurons and synapses integrated in such systems, the neural connectivity and its configurability have become crucial design constraints. To tackle this problem, we introduce a generic extended graph description of connection topologies that allows a systematical analysis of connectivity in both neuromorphic hardware and neural network models. The unifying nature of our approach enables a close exchange between hardware and models. For an existing hardware system, the optimally matched network model can be extracted. Inversely, a hardware architecture may be fitted to a particular model network topology with our description method. As a further strength, the extended graph can be used to quantify the amount of configurability for a certain network topology. This is a hardware design variable that has widely been neglected, mainly because of a missing analysis method. To condense our analysis results, we develop a classification for the scaling complexity of network models and neuromorphic hardware, based on the total number of connections and the configurability. We find a gap between several models and existing hardware, making these hardware systems either impossible or inefficient to use for scaled-up network models. In this respect, our analysis results suggest models with locality in their connections as promising approach for tackling this scaling gap.

  5. Wintertime connections between extreme wind patterns in Spain and large-scale geopotential height field

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    Pascual, A.; Martín, M. L.; Valero, F.; Luna, M. Y.; Morata, A.

    2013-03-01

    The present study is focused on the study of the variability and the most significant wind speed patterns in Spain during the winter season analyzing as well connections between the wind speed field and the geopotential height at 1000 hPa over an Atlantic area. The daily wind speed variability is investigated by means of principal components using wind speed observations. Five main modes of variation, accounting 66% of the variance of the original data, have been identified, highlighting their differences in the Spanish wind speed behavior. Connections between the wind speeds and the large-scale atmospheric field were underlined by means of composite maps. Composite maps were built up to give an averaged atmospheric circulation associated with extreme wind speed variability in Spain. Moreover, the principal component analysis was also applied to the geopotential heights, providing relationships between the large-scale atmospheric modes and the observational local wind speeds. Such relationships are shown in terms of the cumulated frequency values of wind speed associated with the extreme scores of the obtained large-scale atmospheric modes, showing those large-scale atmospheric patterns more dominant in the wind field in Spain.

  6. Analyzing Social Media Networks with NodeXL Insights from a Connected World

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    Hansen, Derek; Smith, Marc A

    2010-01-01

    Businesses, entrepreneurs, individuals, and government agencies alike are looking to social network analysis (SNA) tools for insight into trends, connections, and fluctuations in social media. Microsoft's NodeXL is a free, open-source SNA plug-in for use with Excel. It provides instant graphical representation of relationships of complex networked data. But it goes further than other SNA tools -- NodeXL was developed by a multidisciplinary team of experts that bring together information studies, computer science, sociology, human-computer interaction, and over 20 years of visual analytic theor

  7. Advanced Degrees of Debt: Analyzing the Patterns and Determinants of Graduate Student Borrowing

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    Belasco, Andrew S.; Trivette, Michael J.; Webber, Karen L.

    2014-01-01

    Despite record student debt and the growing importance of graduate education, little is known about what drives graduate student borrowing. In response to that research gap, this study draws on several national data sources to analyze the patterns and predictors of education-related debt among graduate students specifically. Adjusted Wald tests…

  8. Functional Connectivity Patterns of Visual Cortex Reflect its Anatomical Organization.

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    Genç, Erhan; Schölvinck, Marieke Louise; Bergmann, Johanna; Singer, Wolf; Kohler, Axel

    2016-09-01

    The brain is continuously active, even without external input or task demands. This so-called resting-state activity exhibits a highly specific spatio-temporal organization. However, how exactly these activity patterns map onto the anatomical and functional architecture of the brain is still unclear. We addressed this question in the human visual cortex. We determined the representation of the visual field in visual cortical areas of 44 subjects using fMRI and examined resting-state correlations between these areas along the visual hierarchy, their dorsal and ventral segments, and between subregions representing foveal versus peripheral parts of the visual field. We found that retinotopically corresponding regions, particularly those representing peripheral visual fields, exhibit strong correlations. V1 displayed strong internal correlations between its dorsal and ventral segments and the highest correlation with LGN compared with other visual areas. In contrast, V2 and V3 showed weaker correlations with LGN and stronger between-area correlations, as well as with V4 and hMT+. Interhemispheric correlations between homologous areas were especially strong. These correlation patterns were robust over time and only marginally altered under task conditions. These results indicate that resting-state fMRI activity closely reflects the anatomical organization of the visual cortex both with respect to retinotopy and hierarchy.

  9. Analyzing the Effects of UAV Mobility Patterns on Data Collection in Wireless Sensor Networks.

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    Rashed, Sarmad; Soyturk, Mujdat

    2017-02-20

    Sensor nodes in a Wireless Sensor Network (WSN) can be dispersed over a remote sensing area (e.g., the regions that are hardly accessed by human beings). In such kinds of networks, datacollectionbecomesoneofthemajorissues. Getting connected to each sensor node and retrieving the information in time introduces new challenges. Mobile sink usage-especially Unmanned Aerial Vehicles (UAVs)-is the most convenient approach to covering the area and accessing each sensor node in such a large-scale WSN. However, the operation of the UAV depends on some parameters, such as endurance time, altitude, speed, radio type in use, and the path. In this paper, we explore various UAV mobility patterns that follow different paths to sweep the operation area in order to seek the best area coverage with the maximum number of covered nodes in the least amount of time needed by the mobile sink. We also introduce a new metric to formulate the tradeoff between maximizing the covered nodes and minimizing the operation time when choosing the appropriate mobility pattern. A realistic simulation environment is used in order to compare and evaluate the performance of the system. We present the performance results for the explored UAV mobility patterns. The results are very useful to present the tradeoff between maximizing the covered nodes and minimizing the operation time to choose the appropriate mobility pattern.

  10. Analyzing the Effects of UAV Mobility Patterns on Data Collection in Wireless Sensor Networks

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    Rashed, Sarmad; Soyturk, Mujdat

    2017-01-01

    Sensor nodes in a Wireless Sensor Network (WSN) can be dispersed over a remote sensing area (e.g., the regions that are hardly accessed by human beings). In such kinds of networks, data collection becomes one of the major issues. Getting connected to each sensor node and retrieving the information in time introduces new challenges. Mobile sink usage—especially Unmanned Aerial Vehicles (UAVs)—is the most convenient approach to covering the area and accessing each sensor node in such a large-scale WSN. However, the operation of the UAV depends on some parameters, such as endurance time, altitude, speed, radio type in use, and the path. In this paper, we explore various UAV mobility patterns that follow different paths to sweep the operation area in order to seek the best area coverage with the maximum number of covered nodes in the least amount of time needed by the mobile sink. We also introduce a new metric to formulate the tradeoff between maximizing the covered nodes and minimizing the operation time when choosing the appropriate mobility pattern. A realistic simulation environment is used in order to compare and evaluate the performance of the system. We present the performance results for the explored UAV mobility patterns. The results are very useful to present the tradeoff between maximizing the covered nodes and minimizing the operation time to choose the appropriate mobility pattern. PMID:28230727

  11. Patterns of connectivity of spinal interneurons with single muscle afferents.

    Science.gov (United States)

    Quevedo, J; Eguibar, J R; Lomeli, J; Rudomin, P

    1997-07-01

    the intraspinal terminals of single muscle afferents receive synapses from more than one PAD-mediating GABAergic interneuron and that a single last-order interneuron has synaptic connections with a restricted number of intraspinal terminals and/or collaterals of the same afferent fiber. In addition, they support the existence of separate subsets of last-order baclofen-sensitive and baclofen-resistant interneurons that respond predominantly to segmental and to descending inputs. It is suggested that the restricted nature of the PAD plays an important role in the central control of the synaptic effectiveness of group I muscle afferents.

  12. Understanding Spatiotemporal Patterns of Biking Behavior by Analyzing Massive Bike Sharing Data in Chicago.

    Directory of Open Access Journals (Sweden)

    Xiaolu Zhou

    Full Text Available The growing number of bike sharing systems (BSS in many cities largely facilitates biking for transportation and recreation. Most recent bike sharing systems produce time and location specific data, which enables the study of travel behavior and mobility of each individual. However, despite a rapid growth of interest, studies on massive bike sharing data and the underneath travel pattern are still limited. Few studies have explored and visualized spatiotemporal patterns of bike sharing behavior using flow clustering, nor examined the station functional profiles based on over-demand patterns. This study investigated the spatiotemporal biking pattern in Chicago by analyzing massive BSS data from July to December in 2013 and 2014. The BSS in Chicago gained more popularity. About 15.9% more people subscribed to this service. Specifically, we constructed bike flow similarity graph and used fastgreedy algorithm to detect spatial communities of biking flows. By using the proposed methods, we discovered unique travel patterns on weekdays and weekends as well as different travel trends for customers and subscribers from the noisy massive amount data. In addition, we also examined the temporal demands for bikes and docks using hierarchical clustering method. Results demonstrated the modeled over-demand patterns in Chicago. This study contributes to offer better knowledge of biking flow patterns, which was difficult to obtain using traditional methods. Given the trend of increasing popularity of the BSS and data openness in different cities, methods used in this study can extend to examine the biking patterns and BSS functionality in different cities.

  13. Aerial and Terrestrial Patterns: A Novel Approach to Analyzing Human Running.

    Science.gov (United States)

    Gindre, C; Lussiana, T; Hebert-Losier, K; Mourot, L

    2016-01-01

    Biomechanical parameters are often analyzed independently, although running gait is a dynamic system wherein changes in one parameter are likely to affect another. Accordingly, the Volodalen® method provides a model for classifying running patterns into 2 categories, aerial and terrestrial, using a global subjective rating scoring system. We aimed to validate the Volodalen® method by verifying whether the aerial and terrestrial patterns, defined subjectively by a running coach, were associated with distinct objectively-measured biomechanical parameters. The running patterns of 91 individuals were assessed subjectively using the Volodalen® method by an expert running coach during a 10-min running warm-up. Biomechanical parameters were measured objectively using the OptojumpNext® during a 50-m run performed at 3.3, 4.2, and 5 m·s(-1) and were compared between aerial- and terrestrial-classified subjects. Longer contact times and greater leg compression were observed in the terrestrial compared to the aerial runners. The aerial runners exhibited longer flight time, greater center of mass displacement, maximum vertical force and leg stiffness than the terrestrial ones. The subjective categorization of running patterns was associated with distinct objectively-quantified biomechanical parameters. Our results suggest that a subjective holistic assessment of running patterns provides insight into the biomechanics of running gaits of individuals.

  14. Tracking multiple sediment cascades at the river network scale identifies controls and emerging patterns of sediment connectivity

    Science.gov (United States)

    Schmitt, Rafael J. P.; Bizzi, Simone; Castelletti, Andrea

    2016-05-01

    Sediment connectivity in fluvial networks results from the transfer of sediment between multiple sources and sinks. Connectivity scales differently between all sources and sinks as a function of distance, source grain size and sediment supply, network topology and topography, and hydrologic forcing. In this paper, we address the challenge of quantifying sediment connectivity and its controls at the network scale. We expand the concept of a single, catchment-scale sediment cascade toward representing sediment transport from each source as a suite of individual cascading processes. We implement this approach in the herein presented CAtchment Sediment Connectivity And DElivery (CASCADE) modeling framework. In CASCADE, each sediment cascade establishes connectivity between a specific source and its multiple sinks. From a source perspective, the fate of sediment is controlled by its detachment and downstream transport capacity, resulting in a specific trajectory of transfer and deposition. From a sink perspective, the assemblage of incoming cascades defines provenance, sorting, and magnitude of sediment deliveries. At the network scale, this information reveals emerging patterns of connectivity and the location of bottlenecks, where disconnectivity occurs. In this paper, we apply CASCADE to quantitatively analyze the sediment connectivity of a major river system in SE Asia. The approach provides a screening model that can support analyses of large, poorly monitored river systems. We test the sensitivity of CASCADE to various parameters and identify the distribution of energy between the multiple, simultaneously active sediment cascades as key control behind network sediment connectivity. To conclude, CASCADE enables a quantitative, spatially explicit analysis of network sediment connectivity with potential applications in both river science and management.

  15. Deafferentation-Induced Plasticity of Visual Callosal Connections: Predicting Critical Periods and Analyzing Cortical Abnormalities Using Diffusion Tensor Imaging

    Directory of Open Access Journals (Sweden)

    Jaime F. Olavarria

    2012-01-01

    Full Text Available Callosal connections form elaborate patterns that bear close association with striate and extrastriate visual areas. Although it is known that retinal input is required for normal callosal development, there is little information regarding the period during which the retina is critically needed and whether this period correlates with the same developmental stage across species. Here we review the timing of this critical period, identified in rodents and ferrets by the effects that timed enucleations have on mature callosal connections, and compare it to other developmental milestones in these species. Subsequently, we compare these events to diffusion tensor imaging (DTI measurements of water diffusion anisotropy within developing cerebral cortex. We observed that the relationship between the timing of the critical period and the DTI-characterized developmental trajectory is strikingly similar in rodents and ferrets, which opens the possibility of using cortical DTI trajectories for predicting the critical period in species, such as humans, in which this period likely occurs prenatally. Last, we discuss the potential of utilizing DTI to distinguish normal from abnormal cerebral cortical development, both within the context of aberrant connectivity induced by early retinal deafferentation, and more generally as a potential tool for detecting abnormalities associated with neurodevelopmental disorders.

  16. Quantitative measurements of Kikuchi bands in diffraction patterns of backscattered electrons using an electrostatic analyzer.

    Science.gov (United States)

    Went, M R; Winkelmann, A; Vos, M

    2009-09-01

    Diffraction patterns of backscattered electrons can provide important crystallographic information with high spatial resolution. Recently, the dynamical theory of electron diffraction was applied to reproduce in great detail backscattering patterns observed in the scanning electron microscope (SEM). However, a fully quantitative comparison of theory and experiment requires angle-resolved measurements of the intensity and the energy of the backscattered electrons, which is difficult to realize in an SEM. This paper determines diffraction patterns of backscattered electrons using an electrostatic analyzer, operating at energies up to 40 keV with sub-eV energy resolution. Measurements are done for different measurement geometries and incoming energies. Generally a good agreement is found between theory and experiment. This spectrometer also allows us to test the influence of the energy loss of the detected electron on the backscattered electron diffraction pattern. It is found that the amplitude of the intensity variation decreases only slowly with increasing energy loss from 0 to 60 eV.

  17. Improving double patterning flow by analyzing the diffractive orders in the pupil plane

    Science.gov (United States)

    Zeggaoui, N.; Farys, V.; Besacier, M.; Li, Q.; Yesilada, E.; Trouiller, Y.

    2011-04-01

    To print sub 22nm node features, current lithography technology faces some tool limitations. One possible solution to overcome these problems is to use the double patterning technique (DPT). The principle of the double patterning technique is pitch splitting where two adjacent features must be assigned opposite masks (colors) corresponding to different exposures if their pitch is less than a predefined minimum coloring pitch. However, certain design orientations for which pattern features separated by more than the minimum coloring pitch cannot be imaged with either of the two exposures. In these directions, the contrast and the process window are degraded because constructive interferences between diffractive orders in the pupil plane are not sufficient. The 22nm and 16nm nodes require the use of very coherent sources that will be generated using SMO (source mask cooptimization). Such pixelized sources while helpful in improving the contrast for selected configurations, can lead to degrade it for configurations which have not been counted for during the SMO process. Therefore, we analyze the diffractive orders interactions in the pupil plane in order to detect these limited orientations in the design and thus propose a new double patterning decomposition algorithm to enlarge the process window and the contrast of each mask.

  18. Optimization of double patterning split by analyzing diffractive orders in the pupil plane

    Science.gov (United States)

    Zeggaoui, N.; Farys, V.; Trouiller, Y.; Yesilada, E.; Robert, F.; Besacier, M.

    2010-09-01

    In double patterning technology (DPT), two adjacent features must be assigned opposite colors, corresponding to different exposures if their pitch is less than a predefined minimum coloring pitch. However, certain design orientations for which pattern features separated by more than the minimum coloring pitch cannot be imaged with either of the two exposures. In such cases, there are no aerial images formed because in these directions there are no constructive interferences between diffractive orders in the pupil plane. The 22nm and 16nm nodes require the use of pixelized sources that will be generated using SMO (source mask co-optimization). Such pixelized sources while helpful in improving the contrast for selected configurations can lead to degraded contrast for configurations which have not been set during the SMO process. Therefore, we analyze the diffractive orders interactions in the pupil plane in order to detect limited orientations in the design and thus propose a decomposition to overcome the problem.

  19. [Spatial distribution pattern of Chilo suppressalis analyzed by classical method and geostatistics].

    Science.gov (United States)

    Yuan, Zheming; Fu, Wei; Li, Fangyi

    2004-04-01

    Two original samples of Chilo suppressalis and their grid, random and sequence samples were analyzed by classical method and geostatistics to characterize the spatial distribution pattern of C. suppressalis. The limitations of spatial distribution analysis with classical method, especially influenced by the original position of grid, were summarized rather completely. On the contrary, geostatistics characterized well the spatial distribution pattern, congregation intensity and spatial heterogeneity of C. suppressalis. According to geostatistics, the population was up to Poisson distribution in low density. As for higher density population, its distribution was up to aggregative, and the aggregation intensity and dependence range were 0.1056 and 193 cm, respectively. Spatial heterogeneity was also found in the higher density population. Its spatial correlativity in line direction was more closely than that in row direction, and the dependence ranges in line and row direction were 115 and 264 cm, respectively.

  20. Contrast and Contact:A Patterning of Alienation and Connection Embodiment in Pangs of Love

    Institute of Scientific and Technical Information of China (English)

    李新颖

    2014-01-01

    The profound meaning of a text is usually expressed by unique linguistic means. This paper argues that the language patterning plays an important role in depicting the relationship between the mother and sons in Pangs of Love. Through analysis of language patterning which features four groups of contrast and contact in this story, this paper suggests the relationship of both alienation and connection. This study illuminates a new way to look at the relationship between the two Chinese American generations.

  1. Patterns and persistence of larval retention and connectivity in a marine fish metapopulation

    KAUST Repository

    Saenz Agudelo, Pablo

    2012-08-14

    Connectivity, the demographic linking of local populations through the dispersal of individuals, is one of the most poorly understood processes in population dynamics, yet has profound implications for conservation and harvest strategies. For marine species with pelagic larvae, direct estimation of connectivity remains logistically challenging and has mostly been limited to single snapshots in time. Here, we document seasonal and interannual patterns of larval dispersal in a metapopulation of the coral reef fish Amphiprion polymnus. A 3-year record of larval trajectories within and among nine discrete local populations from an area of approximately 35 km was established by determining the natal origin of settled juveniles through DNA parentage analysis. We found that spatial patterns of both self-recruitment and connectivity were remarkably consistent over time, with a low level of self-recruitment at the scale of individual sites. Connectivity among sites was common and multidirectional in all years and was not significantly influenced by seasonal variability of predominant surface current directions. However, approximately 75% of the sampled juveniles could not be assigned to parents within the study area, indicating high levels of immigrations from sources outside the study area. The data support predictions that the magnitude and temporal stability of larval connectivity decreases significantly with increasing distance between subpopulations, but increases with the size of subpopulations. Given the considerable effort needed to directly measure larval exchange, the consistent patterns suggest snapshot parentage analyses can provide useful dispersal estimates to inform spatial management decisions. © 2012 Blackwell Publishing Ltd.

  2. A fractal growth model: Exploring the connection pattern of hubs in complex networks

    Science.gov (United States)

    Li, Dongyan; Wang, Xingyuan; Huang, Penghe

    2017-04-01

    Fractal is ubiquitous in many real-world networks. Previous researches showed that the strong disassortativity between the hub-nodes on all length scales was the key principle that gave rise to the fractal architecture of networks. Although fractal property emerged in some models, there were few researches about the fractal growth model and quantitative analyses about the strength of the disassortativity for fractal model. In this paper, we proposed a novel inverse renormalization method, named Box-based Preferential Attachment (BPA), to build the fractal growth models in which the Preferential Attachment was performed at box level. The proposed models provided a new framework that demonstrated small-world-fractal transition. Also, we firstly demonstrated the statistical characteristic of connection patterns of the hubs in fractal networks. The experimental results showed that, given proper growing scale and added edges, the proposed models could clearly show pure small-world or pure fractal or both of them. It also showed that the hub connection ratio showed normal distribution in many real-world networks. At last, the comparisons of connection pattern between the proposed models and the biological and technical networks were performed. The results gave useful reference for exploring the growth principle and for modeling the connection patterns for real-world networks.

  3. The structural connectivity pattern of the default mode network and its association with memory and anxiety

    Directory of Open Access Journals (Sweden)

    Yan eTao

    2015-11-01

    Full Text Available The default mode network (DMN is one of the most widely studied resting state functional networks. The structural basis for the DMN is of particular interest and has been studied by several researchers using diffusion tensor imaging (DTI. Most of these previous studies focused on a few regions or white matter tracts of the DMN so that the global structural connectivity pattern and network properties of the DMN remain unclear. Moreover, evidences indicate that the DMN is involved in both memory and emotion, but how the DMN regulates memory and anxiety from the perspective of the whole DMN structural network remains unknown. We used multimodal neuroimaging methods to investigate the structural connectivity pattern of the DMN and the association of its network properties with memory and anxiety in 205 young healthy subjects. Using a probabilistic fiber tractography technique based on DTI data and graph theory methods, we constructed the global structural connectivity pattern of the DMN and found that memory quotient (MQ score was significantly positively correlated with the global and local efficiency of the DMN whereas anxiety was found to be negatively correlated with the efficiency. The strong structural connectivity between multiple brain regions within DMN may reflect that the DMN has certain structural basis. Meanwhile, we found the network efficiency of the DMN were related to memory and anxiety measures, which indicated that the DMN may play a role in the memory and anxiety.

  4. Discriminative analysis of brain functional connectivity patterns for mental fatigue classification.

    Science.gov (United States)

    Sun, Yu; Lim, Julian; Meng, Jianjun; Kwok, Kenneth; Thakor, Nitish; Bezerianos, Anastasios

    2014-10-01

    Mental fatigue is a commonly experienced state that can be induced by placing heavy demands on cognitive systems. This often leads to lowered productivity and increased safety risks. In this study, we developed a functional-connectivity based mental fatigue monitoring method. Twenty-six subjects underwent a 20-min mentally demanding test of sustained attention with high-resolution EEG monitoring. Functional connectivity patterns were obtained on the cortical surface via source localization of cortical activities in the first and last 5-min quartiles of the experiment. Multivariate pattern analysis was then adopted to extract the highly discriminative functional connectivity information. The algorithm used in the present study demonstrated an overall accuracy of 81.5% (p fatigue classification through leave-one-out cross validation. Moreover, we found that the most discriminative connectivity features were located in or across middle frontal gyrus and several motor areas, in agreement with the important role that these cortical regions play in the maintenance of sustained attention. This work therefore demonstrates the feasibility of a functional-connectivity-based mental fatigue assessment method, opening up a new avenue for modeling natural brain dynamics under different mental states. Our method has potential applications in several domains, including traffic and industrial safety.

  5. Analyzing ChIP-seq data: preprocessing, normalization, differential identification, and binding pattern characterization.

    Science.gov (United States)

    Taslim, Cenny; Huang, Kun; Huang, Tim; Lin, Shili

    2012-01-01

    Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is a high-throughput antibody-based method to study genome-wide protein-DNA binding interactions. ChIP-seq technology allows scientist to obtain more accurate data providing genome-wide coverage with less starting material and in shorter time compared to older ChIP-chip experiments. Herein we describe a step-by-step guideline in analyzing ChIP-seq data including data preprocessing, nonlinear normalization to enable comparison between different samples and experiments, statistical-based method to identify differential binding sites using mixture modeling and local false discovery rates (fdrs), and binding pattern characterization. In addition, we provide a sample analysis of ChIP-seq data using the steps provided in the guideline.

  6. Application of a clustering-remote sensing method in analyzing security patterns

    Science.gov (United States)

    López-Caloca, Alejandra; Martínez-Viveros, Elvia; Chapela-Castañares, José Ignacio

    2009-04-01

    In Mexican academic and government circles, research on criminal spatial behavior has been neglected. Only recently has there been an interest in criminal data geo-reference. However, more sophisticated spatial analyses models are needed to disclose spatial patterns of crime and pinpoint their changes overtime. The main use of these models lies in supporting policy making and strategic intelligence. In this paper we present a model for finding patterns associated with crime. It is based on a fuzzy logic algorithm which finds the best fit within cluster numbers and shapes of groupings. We describe the methodology for building the model and its validation. The model was applied to annual data for types of felonies from 2005 to 2006 in the Mexican city of Hermosillo. The results are visualized as a standard deviational ellipse computed for the points identified to be a "cluster". These areas indicate a high to low demand for public security, and they were cross-related to urban structure analyzed by SPOT images and statistical data such as population, poverty levels, urbanization, and available services. The fusion of the model results with other geospatial data allows detecting obstacles and opportunities for crime commission in specific high risk zones and guide police activities and criminal investigations.

  7. Connectivity strategies for higher-order neural networks applied to pattern recognition

    Science.gov (United States)

    Spirkovska, Lilly; Reid, Max B.

    1990-01-01

    Different strategies for non-fully connected HONNs (higher-order neural networks) are discussed, showing that by using such strategies an input field of 128 x 128 pixels can be attained while still achieving in-plane rotation and translation-invariant recognition. These techniques allow HONNs to be used with the larger input scenes required for practical pattern-recognition applications. The number of interconnections that must be stored has been reduced by a factor of approximately 200,000 in a T/C case and about 2000 in a Space Shuttle/F-18 case by using regional connectivity. Third-order networks have been simulated using several connection strategies. The method found to work best is regional connectivity. The main advantages of this strategy are the following: (1) it considers features of various scales within the image and thus gets a better sample of what the image looks like; (2) it is invariant to shape-preserving geometric transformations, such as translation and rotation; (3) the connections are predetermined so that no extra computations are necessary during run time; and (4) it does not require any extra storage for recording which connections were formed.

  8. Application of frequent itemsets mining to analyze patterns of one-stop visits in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chun-Yi Tu

    Full Text Available BACKGROUND: The free choice of health care facilities without limitations on frequency of visits within the National Health Insurance in Taiwan gives rise to not only a high number of annual ambulatory visits per capita but also a unique "one-stop shopping"phenomenon, which refers to a patient' visits to several specialties of the same healthcare facility in one day. The visits to multiple physicians would increase the potential risk of polypharmacy. The aim of this study was to analyze the frequency and patterns of one-stop visits in Taiwan. METHODOLOGY/PRINCIPAL FINDINGS: The claims datasets of 1 million nationally representative people within Taiwan's National Health Insurance in 2005 were used to calculate the number of patients with one-stop visits. The frequent itemsets mining was applied to compute the combination patterns of specialties in the one-stop visits. Among the total 13,682,469 ambulatory care visits in 2005, one-stop visits occurred 144,132 times and involved 296,822 visits (2.2% of all visits by 66,294 (6.6% persons. People tended to have this behavior with age and the percentage reached 27.5% (5,662 in 20,579 in the age group ≥80 years. In general, women were more likely to have one-stop visits than men (7.2% vs. 6.0%. Internal medicine plus ophthalmology was the most frequent combination with a visited frequency of 3,552 times (2.5%, followed by cardiology plus neurology with 3,183 times (2.2%. The most frequent three-specialty combination, cardiology plus neurology and gastroenterology, occurred only 111 times. CONCLUSIONS/SIGNIFICANCE: Without the novel computational technique, it would be hardly possible to analyze the extremely diverse combination patterns of specialties in one-stop visits. The results of the study could provide useful information either for the hospital manager to set up integrated services or for the policymaker to rebuild the health care system.

  9. Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile.

    Science.gov (United States)

    Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe

    2016-01-01

    In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.

  10. Temporal metastates are associated with differential patterns of time-resolved connectivity, network topology, and attention.

    Science.gov (United States)

    Shine, James M; Koyejo, Oluwasanmi; Poldrack, Russell A

    2016-08-30

    Little is currently known about the coordination of neural activity over longitudinal timescales and how these changes relate to behavior. To investigate this issue, we used resting-state fMRI data from a single individual to identify the presence of two distinct temporal states that fluctuated over the course of 18 mo. These temporal states were associated with distinct patterns of time-resolved blood oxygen level dependent (BOLD) connectivity within individual scanning sessions and also related to significant alterations in global efficiency of brain connectivity as well as differences in self-reported attention. These patterns were replicated in a separate longitudinal dataset, providing additional supportive evidence for the presence of fluctuations in functional network topology over time. Together, our results underscore the importance of longitudinal phenotyping in cognitive neuroscience.

  11. A signaling network for patterning of neuronal connectivity in the Drosophila brain.

    Directory of Open Access Journals (Sweden)

    Mohammed Srahna

    2006-10-01

    Full Text Available The precise number and pattern of axonal connections generated during brain development regulates animal behavior. Therefore, understanding how developmental signals interact to regulate axonal extension and retraction to achieve precise neuronal connectivity is a fundamental goal of neurobiology. We investigated this question in the developing adult brain of Drosophila and find that it is regulated by crosstalk between Wnt, fibroblast growth factor (FGF receptor, and Jun N-terminal kinase (JNK signaling, but independent of neuronal activity. The Rac1 GTPase integrates a Wnt-Frizzled-Disheveled axon-stabilizing signal and a Branchless (FGF-Breathless (FGF receptor axon-retracting signal to modulate JNK activity. JNK activity is necessary and sufficient for axon extension, whereas the antagonistic Wnt and FGF signals act to balance the extension and retraction required for the generation of the precise wiring pattern.

  12. Visualization of roaming client/server connection patterns during a wirelessly enabled disaster response drill.

    Science.gov (United States)

    Calvitti, Alan; Lenert, Leslie A; Brown, Steven W

    2006-01-01

    Assessment of how well a multiple client server system is functioning is a difficult task. In this poster we present visualization tools for such assessments. Arranged on a timeline, UDP client connection events are point-like. TCP client events are structured into intervals. Informative patterns and correlations are revealed by both sets. For the latter, comparison of two visualization schemes on the same timeline yields additional insights.

  13. A word-count approach to analyze linguistic patterns in the reflective writings of medical students

    Directory of Open Access Journals (Sweden)

    Chi-Wei Lin

    2016-02-01

    Full Text Available Background: Teaching reflection and administering reflective writing assignments to students are widely practiced and discussed in medical education and health professional education. However, little is known about how medical students use language to construct their narratives. Exploring students’ linguistic patterns in their reflective writings can facilitate understanding the scope and facets of their reflections and their representational or communication approaches to share their experiences. Moreover, research findings regarding gender differences in language use are inconsistent. Therefore, we attempted to examine how females and males differ in their use of words in reflective writing within our research circumstance to detect the unique and gender-specific approaches to learning and their applications. Methods: We analyzed the linguistic profiles of psychological process categories in the reflective writings of medical students and examined the difference in word usage between male and female medical students. During the first year of a clinical rotation, 60 fifth-year medical students wrote reflective narratives regarding pediatric patients and the psychosocial challenges faced by the patients and their family members. The narratives were analyzed using the Chinese version of Linguistic Inquiry and Word Count (CLIWC, a text analysis software program. Multivariate procedures were applied for statistical analysis. Results: Cognitive words were most pervasive, averaging 22.16%, whereas perceptual words (2.86% were least pervasive. Female students used more words related to positive emotions and sadness than did male students. The male students exceeded the female students only in the space category. The major limitation of this study is that CLIWC cannot directly acquire contextual text meanings; therefore, depending on the research topic, further qualitative study of the given texts might be necessary. Conclusions: To enhance students

  14. Connectivity patterns and rotamer states of nucleobases determine acid-base properties of metalated purine quartets.

    Science.gov (United States)

    Lüth, Marc Sven; Freisinger, Eva; Kampf, Gunnar; Garijo Anorbe, Marta; Griesser, Rolf; Operschall, Bert P; Sigel, Helmut; Lippert, Bernhard

    2015-07-01

    Potentiometric pH titrations and pD dependent (1)H NMR spectroscopy have been applied to study the acidification of the exocyclic amino group of adenine (A) model nucleobases (N9 position blocked by alkyl groups) when carrying trans-a2Pt(II) (with a=NH3 or CH3NH2) entities both at N1 and N7 positions. As demonstrated, in trinuclear complexes containing central A-Pt-A units, it depends on the connectivity pattern of the adenine bases (N7/N7 or N1/N1) and their rotamer states (head-head or head-tail), how large the acidifying effect is. Specifically, a series of trinuclear complexes with (A-N7)-Pt-(N7-A) and (A-N1)-Pt-(N1-A) cross-linking patterns and terminal 9-alkylguanine ligands (9MeGH, 9EtGH) have been analyzed in this respect, and it is shown that, for example, the 9MeA ligands in trans-,trans-,trans-[Pt(NH3)2(N7-9MeA-N1)2{Pt(NH3)2(9EtGH-N7)}2](ClO4)6·6H2O (4a) and trans-,trans-,trans-[Pt(NH3)2(N7-9EtA-N1)2{Pt(CH3NH2)2(9-MeGH-N7)}2](ClO4)6·3H2O (4b) are more acidic, by ca. 1.3 units (first pKa), than the linkage isomer trans-,trans-,trans-[Pt(CH3NH2)2(N1-9MeA-N7)2{Pt(NH3)2(9MeGH-N7)}2](NO3)6·6.25H2O (1b). Overall, acidifications in these types of complexes amount to 7-9 units, bringing the pKa values of such adenine ligands in the best case close to the physiological pH range. Comparison with pKa values of related trinuclear Pt(II) complexes having different co-ligands at the Pt ions, confirms this picture and supports our earlier proposal that the close proximity of the exocyclic amino groups in a head-head arrangement of (A-N7)-Pt-(N7-A), and the stabilization of the resulting N6H(-)⋯H2N6 unit, is key to this difference.

  15. Exploratory graphical models of functional and structural connectivity patterns for Alzheimer's Disease diagnosis

    Science.gov (United States)

    Ortiz, Andrés; Munilla, Jorge; Álvarez-Illán, Ignacio; Górriz, Juan M.; Ramírez, Javier

    2015-01-01

    Alzheimer's Disease (AD) is the most common neurodegenerative disease in elderly people. Its development has been shown to be closely related to changes in the brain connectivity network and in the brain activation patterns along with structural changes caused by the neurodegenerative process. Methods to infer dependence between brain regions are usually derived from the analysis of covariance between activation levels in the different areas. However, these covariance-based methods are not able to estimate conditional independence between variables to factor out the influence of other regions. Conversely, models based on the inverse covariance, or precision matrix, such as Sparse Gaussian Graphical Models allow revealing conditional independence between regions by estimating the covariance between two variables given the rest as constant. This paper uses Sparse Inverse Covariance Estimation (SICE) methods to learn undirected graphs in order to derive functional and structural connectivity patterns from Fludeoxyglucose (18F-FDG) Position Emission Tomography (PET) data and segmented Magnetic Resonance images (MRI), drawn from the ADNI database, for Control, MCI (Mild Cognitive Impairment Subjects), and AD subjects. Sparse computation fits perfectly here as brain regions usually only interact with a few other areas. The models clearly show different metabolic covariation patters between subject groups, revealing the loss of strong connections in AD and MCI subjects when compared to Controls. Similarly, the variance between GM (Gray Matter) densities of different regions reveals different structural covariation patterns between the different groups. Thus, the different connectivity patterns for controls and AD are used in this paper to select regions of interest in PET and GM images with discriminative power for early AD diagnosis. Finally, functional an structural models are combined to leverage the classification accuracy. The results obtained in this work show the

  16. Exploratory graphical models of functional and structural connectivity patterns for Alzheimer's Disease diagnosis

    Directory of Open Access Journals (Sweden)

    Andres eOrtiz

    2015-11-01

    Full Text Available Alzheimer’s Disease (AD is the most common neurodegenerative disease in elderly people. Itsdevelopment has been shown to be closely related to changes in the brain connectivity networkand in the brain activation patterns along with structural changes caused by the neurodegenerativeprocess.Methods to infer dependence between brain regions are usually derived from the analysis ofcovariance between activation levels in the different areas. However, these covariance-basedmethods are not able to estimate conditional independence between variables to factor out theinfluence of other regions. Conversely, models based on the inverse covariance, or precisionmatrix, such as Sparse Gaussian Graphical Models allow revealing conditional independencebetween regions by estimating the covariance between two variables given the rest as constant.This paper uses Sparse Inverse Covariance Estimation (SICE methods to learn undirectedgraphs in order to derive functional and structural connectivity patterns from Fludeoxyglucose(18F-FDG Position Emission Tomography (PET data and segmented Magnetic Resonanceimages (MRI, drawn from the ADNI database, for Control, MCI (Mild Cognitive ImpairmentSubjects and AD subjects. Sparse computation fits perfectly here as brain regions usually onlyinteract with a few other areas.The models clearly show different metabolic covariation patters between subject groups, revealingthe loss of strong connections in AD and MCI subjects when compared to Controls. Similarly,the variance between GM (Grey Matter densities of different regions reveals different structuralcovariation patterns between the different groups. Thus, the different connectivity patterns forcontrols and AD are used in this paper to select regions of interest in PET and GM images withdiscriminative power for early AD diagnosis. Finally, functional an structural models are combinedto leverage the classification accuracy.The results obtained in this work show the usefulness

  17. Congruent patterns of connectivity can inform management for broadcast spawning corals on the Great Barrier Reef.

    Science.gov (United States)

    Lukoschek, Vimoksalehi; Riginos, Cynthia; van Oppen, Madeleine J H

    2016-07-01

    Connectivity underpins the persistence and recovery of marine ecosystems. The Great Barrier Reef (GBR) is the world's largest coral reef ecosystem and managed by an extensive network of no-take zones; however, information about connectivity was not available to optimize the network's configuration. We use multivariate analyses, Bayesian clustering algorithms and assignment tests of the largest population genetic data set for any organism on the GBR to date (Acropora tenuis, >2500 colonies; >50 reefs, genotyped for ten microsatellite loci) to demonstrate highly congruent patterns of connectivity between this common broadcast spawning reef-building coral and its congener Acropora millepora (~950 colonies; 20 reefs, genotyped for 12 microsatellite loci). For both species, there is a genetic divide at around 19°S latitude, most probably reflecting allopatric differentiation during the Pleistocene. GBR reefs north of 19°S are essentially panmictic whereas southern reefs are genetically distinct with higher levels of genetic diversity and population structure, most notably genetic subdivision between inshore and offshore reefs south of 19°S. These broadly congruent patterns of higher genetic diversities found on southern GBR reefs most likely represent the accumulation of alleles via the southward flowing East Australia Current. In addition, signatures of genetic admixture between the Coral Sea and outer-shelf reefs in the northern, central and southern GBR provide evidence of recent gene flow. Our connectivity results are consistent with predictions from recently published larval dispersal models for broadcast spawning corals on the GBR, thereby providing robust connectivity information about the dominant reef-building genus Acropora for coral reef managers.

  18. Watershed Ecohydrology: How Do Vegetation Patterns and Climate Affect Watershed Storage and Connectivity?

    Science.gov (United States)

    Nippgen, F.; McGlynn, B. L.; Emanuel, R. E.

    2015-12-01

    Topography and soils have long been recognized as mediators of runoff source areas, but the effect of vegetation patterns on subsurface throughflow is less well understood. While numerous studies have shown that vegetation removal generally leads to increases in streamflow, few studies have examined the intersection between patterns of evapotranspiration and topographically driven patterns of throughflow generation and connectivity. We applied a parsimonious but spatially distributed watershed modeling framework (WECOH: Watershed ECOHydrology Model) to a snow dominated watershed in central Montana to elucidate how different vegetation scenarios and climate forcing can affect the temporal evolution of storage distributions and watershed connectivity. We derived spatially distributed snowmelt and rainfall input from two NRCS SNOTEL sites located in the experimental watershed and actual evapotranspiration from a co-located eddy-covariance tower. We generated different vegetation scenarios to simulate forest harvesting and compared streamflow response, spatial distribution of storage, and runoff source areas across scenarios. Our work aims at better understanding how the intersection of vegetation and topography mediates hydrologic response.

  19. Abnormal brain connectivity patterns in adults with ADHD: a coherence study.

    Directory of Open Access Journals (Sweden)

    João Ricardo Sato

    Full Text Available Studies based on functional magnetic resonance imaging (fMRI during the resting state have shown decreased functional connectivity between the dorsal anterior cingulate cortex (dACC and regions of the Default Mode Network (DMN in adult patients with Attention-Deficit/Hyperactivity Disorder (ADHD relative to subjects with typical development (TD. Most studies used Pearson correlation coefficients among the BOLD signals from different brain regions to quantify functional connectivity. Since the Pearson correlation analysis only provides a limited description of functional connectivity, we investigated functional connectivity between the dACC and the posterior cingulate cortex (PCC in three groups (adult patients with ADHD, n=21; TD age-matched subjects, n=21; young TD subjects, n=21 using a more comprehensive analytical approach - unsupervised machine learning using a one-class support vector machine (OC-SVM that quantifies an abnormality index for each individual. The median abnormality index for patients with ADHD was greater than for TD age-matched subjects (p=0.014; the ADHD and young TD indices did not differ significantly (p=0.480; the median abnormality index of young TD was greater than that of TD age-matched subjects (p=0.016. Low frequencies below 0.05 Hz and around 0.20 Hz were the most relevant for discriminating between ADHD patients and TD age-matched controls and between the older and younger TD subjects. In addition, we validated our approach using the fMRI data of children publicly released by the ADHD-200 Competition, obtaining similar results. Our findings suggest that the abnormal coherence patterns observed in patients with ADHD in this study resemble the patterns observed in young typically developing subjects, which reinforces the hypothesis that ADHD is associated with brain maturation deficits.

  20. Point processes and random sets for analyzing patterns of methylene blue coloured soil.

    NARCIS (Netherlands)

    Stein, A.; Droogers, P.; Booltink, H.

    1998-01-01

    We consider the problem of quantitatively characterizing horizontal patterns of dye following infiltration. Such patterns display important information on the movement of possibly contaminated solutes from the soil surface to the ground water, which may cause risks for human health. The stains were

  1. Dermatoglyphics of Easter Islanders analyzed by pattern type, admixture effect, and ridge count variation.

    Science.gov (United States)

    Meier, R J

    1975-03-01

    The adult Easter Island population was fingerprinted in 1965 as part of an overall study of their human biology. Major findings of the dermatoglyphic analysis are as follows. Digit and bimanuar percentages of patterns (arches, loops, and whorls) were similar to those observed in Europeans. However, in terms of total pattern type distributions, the Islanders had many more whorls and a correspondingly much higher Pattern Intensity Index than those found in European groups. This difference was even present, although in lesser magnitude, in Easter Islanders known to be admixed with Europeans. Corresponding to a high occurrence of whorls, Mean Total Ridge Count (TRC) was also notably high. An association between TRC as a measure of pattern size and incidence of patterns was clearly evident in several groups available for comparison.

  2. Constrained Synaptic Connectivity in Functional Mammalian Neuronal Networks Grown on Patterned Surfaces

    Science.gov (United States)

    Bourdieu, Laurent; Wyart, Claire; Ybert, Christophe; Herr, Catherine; Chatenay, Didier

    2002-03-01

    The use of ordered neuronal networks in vitro is a promising approach to study the development and the activity of neuronal assemblies. However in previous attempts, sufficient growth control and physiological maturation of neurons could not be achieved. We describe an original protocol in which polylysine patterns confine the adhesion of cellular bodies to prescribed spots and the neuritic growth to thin lines. Hippocampal neurons are maintained healthy in serum free medium up to five weeks in vitro. Electrophysiology and immunochemistry show that neurons exhibit mature excitatory and inhibitory synapses and calcium imaging reveals spontaneous bursting activity of neurons in isolated networks. Neurons in these geometrical networks form functional synapses preferentially to their first neighbors. We have therefore established a simple and robust protocol to constrain both the location of neuronal cell bodies and their pattern of connectivity.

  3. Analyzing the causes and spatial pattern of the European 2003 carbon flux anomaly using seven models

    Directory of Open Access Journals (Sweden)

    M. Vetter

    2008-04-01

    Full Text Available Globally, the year 2003 is associated with one of the largest atmospheric CO2 rises on record. In the same year, Europe experienced an anomalously strong flux of CO2 from the land to the atmosphere associated with an exceptionally dry and hot summer in Western and Central Europe. In this study we analyze the magnitude of this carbon flux anomaly and key driving ecosystem processes using simulations of seven terrestrial ecosystem models of different complexity and types (process-oriented and diagnostic. We address the following questions: (1 how large were deviations in the net European carbon flux in 2003 relative to a short-term baseline (1998–2002 and to longer-term variations in annual fluxes (1980 to 2005, (2 which European regions exhibited the largest changes in carbon fluxes during the growing season 2003, and (3 which ecosystem processes controlled the carbon balance anomaly .

    In most models the prominence of 2003 anomaly in carbon fluxes declined with lengthening of the reference period from one year to 16 years. The 2003 anomaly for annual net carbon fluxes ranged between 0.35 and –0.63 Pg C for a reference period of one year and between 0.17 and –0.37 Pg C for a reference period of 16 years for the whole Europe.

    In Western and Central Europe, the anomaly in simulated net ecosystem productivity (NEP over the growing season in 2003 was outside the 1σ variance bound of the carbon flux anomalies for 1980–2005 in all models. The estimated anomaly in net carbon flux ranged between –42 and –158 Tg C for Western Europe and between 24 and –129 Tg C for Central Europe depending on the model used. All models responded to a dipole pattern of the climate anomaly in 2003. In Western and Central Europe NEP was reduced due to heat and drought. In contrast, lower than normal temperatures and higher air humidity decreased NEP over Northeastern Europe. While models agree on the sign of changes in

  4. Analyzing a problem-solution pattern in the transcription of a conversation: suggestions for the ELF classroom

    OpenAIRE

    Navas Brenes, César A.

    2005-01-01

    This paper analyzes a problem-solution pattern shown in the transcription of a conversation. This analysis is based on a conversation that has been elicited from three native speakers of English. These speakers were given a topic that dealt with the problem of children being constantly exposed to violent video games. As a result, the writer recorded an oral text that contains several elements related to a problem-solution pattern such as the main issue, opinions, personal examples, possible s...

  5. Preschool anxiety disorders predict different patterns of amygdala-prefrontal connectivity at school-age.

    Directory of Open Access Journals (Sweden)

    Kimberly L H Carpenter

    Full Text Available In this prospective, longitudinal study of young children, we examined whether a history of preschool generalized anxiety, separation anxiety, and/or social phobia is associated with amygdala-prefrontal dysregulation at school-age. As an exploratory analysis, we investigated whether distinct anxiety disorders differ in the patterns of this amygdala-prefrontal dysregulation.Participants were children taking part in a 5-year study of early childhood brain development and anxiety disorders. Preschool symptoms of generalized anxiety, separation anxiety, and social phobia were assessed with the Preschool Age Psychiatric Assessment (PAPA in the first wave of the study when the children were between 2 and 5 years old. The PAPA was repeated at age 6. We conducted functional MRIs when the children were 5.5 to 9.5 year old to assess neural responses to viewing of angry and fearful faces.A history of preschool social phobia predicted less school-age functional connectivity between the amygdala and the ventral prefrontal cortices to angry faces. Preschool generalized anxiety predicted less functional connectivity between the amygdala and dorsal prefrontal cortices in response to fearful faces. Finally, a history of preschool separation anxiety predicted less school-age functional connectivity between the amygdala and the ventral prefrontal cortices to angry faces and greater school-age functional connectivity between the amygdala and dorsal prefrontal cortices to angry faces.Our results suggest that there are enduring neurobiological effects associated with a history of preschool anxiety, which occur over-and-above the effect of subsequent emotional symptoms. Our results also provide preliminary evidence for the neurobiological differentiation of specific preschool anxiety disorders.

  6. A three-dimensional spatio-temporal EEG pattern analyzing system

    Institute of Scientific and Technical Information of China (English)

    LIU Hesheng; GAO Xiaorong; YANG Fusheng

    2003-01-01

    Spatio-temporal pattern analysis of EEG is an important tool in brain research. An EEG pattern analysis system based on a hierarchical multi-method approach is proposed here. The system consists of multiple steps including extraction of target signal, acquisition of intracranial electric activity distribution, adaptive segmentation of EEG and spatio-temporal pattern recognition. Some modern signal processing methods such as common spatial subspace decomposition, hidden Markov model are adopted. This paper also proposes an algorithm named LORETA-FOCUSS to estimate the current density inside the brain with a high spatial resolution. Microstate analysis of EEG is extended to the 3-D situation. The system was applied to the brain computer interface problem and achieved the highest accuracy of 88.89% with an average accuracy of 81.48% when classifying two imaginary movement tasks, while the data were not manually pre-selected. The result has proved spatio-temporal EEG pattern analysis is an efficient way in brain research.

  7. Mapping Classroom Interactions: A Spatial Approach to Analyzing Patterns of Student Participation

    Science.gov (United States)

    Abbot, Sophia; Cook-Sather, Alison; Hein, Carola

    2014-01-01

    This article explores how mapping patterns of student participation in classroom discussion can both illuminate and complicate the dynamic relationships among identity, physical position in the classroom, student engagement, and course content. It draws on the perspectives of an undergraduate in the role of pedagogical consultant, a faculty member…

  8. Geometry and Morphology of the Cosmic Web : Analyzing Spatial Patterns in the Universe

    NARCIS (Netherlands)

    van de Weygaert, Rien; Jones, Bernard J. T.; Platen, Erwin; Aragon-Calvo, Miguel A.; Anton, F

    2009-01-01

    We review the analysis of the Cosmic Web by means of an extensive toolset based on the use of Delaunay and Voronoi tessellations. The Cosmic Web is the salient and pervasive foamlike pattern in which matter has organized itself on scales of a few up to more than a hundred Megaparsec. The weblike spa

  9. Analyzing collaboration networks and developmental patterns of nano-enabled drug delivery (NEDD) for brain cancer.

    Science.gov (United States)

    Huang, Ying; Ma, Jing; Porter, Alan L; Kwon, Seokbeom; Zhu, Donghua

    2015-01-01

    The rapid development of new and emerging science & technologies (NESTs) brings unprecedented challenges, but also opportunities. In this paper, we use bibliometric and social network analyses, at country, institution, and individual levels, to explore the patterns of scientific networking for a key nano area - nano-enabled drug delivery (NEDD). NEDD has successfully been used clinically to modulate drug release and to target particular diseased tissues. The data for this research come from a global compilation of research publication information on NEDD directed at brain cancer. We derive a family of indicators that address multiple facets of research collaboration and knowledge transfer patterns. Results show that: (1) international cooperation is increasing, but networking characteristics change over time; (2) highly productive institutions also lead in influence, as measured by citation to their work, with American institutes leading; (3) research collaboration is dominated by local relationships, with interesting information available from authorship patterns that go well beyond journal impact factors. Results offer useful technical intelligence to help researchers identify potential collaborators and to help inform R&D management and science & innovation policy for such nanotechnologies.

  10. Analyzing collaboration networks and developmental patterns of nano-enabled drug delivery (NEDD for brain cancer

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2015-07-01

    Full Text Available The rapid development of new and emerging science & technologies (NESTs brings unprecedented challenges, but also opportunities. In this paper, we use bibliometric and social network analyses, at country, institution, and individual levels, to explore the patterns of scientific networking for a key nano area – nano-enabled drug delivery (NEDD. NEDD has successfully been used clinically to modulate drug release and to target particular diseased tissues. The data for this research come from a global compilation of research publication information on NEDD directed at brain cancer. We derive a family of indicators that address multiple facets of research collaboration and knowledge transfer patterns. Results show that: (1 international cooperation is increasing, but networking characteristics change over time; (2 highly productive institutions also lead in influence, as measured by citation to their work, with American institutes leading; (3 research collaboration is dominated by local relationships, with interesting information available from authorship patterns that go well beyond journal impact factors. Results offer useful technical intelligence to help researchers identify potential collaborators and to help inform R&D management and science & innovation policy for such nanotechnologies.

  11. A systems level strategy for analyzing the cell death network: implication in exploring the apoptosis/autophagy connection.

    Science.gov (United States)

    Zalckvar, E; Yosef, N; Reef, S; Ber, Y; Rubinstein, A D; Mor, I; Sharan, R; Ruppin, E; Kimchi, A

    2010-08-01

    The mammalian cell death network comprises three distinct functional modules: apoptosis, autophagy and programmed necrosis. Currently, the field lacks systems level approaches to assess the extent to which the intermodular connectivity affects cell death performance. Here, we developed a platform that is based on single and double sets of RNAi-mediated perturbations targeting combinations of apoptotic and autophagic genes. The outcome of perturbations is measured both at the level of the overall cell death responses, using an unbiased quantitative reporter, and by assessing the molecular responses within the different functional modules. Epistatic analyses determine whether seemingly unrelated pairs of proteins are genetically linked. The initial running of this platform in etoposide-treated cells, using a few single and double perturbations, identified several levels of connectivity between apoptosis and autophagy. The knock down of caspase3 turned on a switch toward autophagic cell death, which requires Atg5 or Beclin-1. In addition, a reciprocal connection between these two autophagic genes and apoptosis was identified. By applying computational tools that are based on mining the protein-protein interaction database, a novel biochemical pathway connecting between Atg5 and caspase3 is suggested. Scaling up this platform into hundreds of perturbations potentially has a wide, general scope of applicability, and will provide the basis for future modeling of the cell death network.

  12. Persistence of self-recruitment and patterns of larval connectivity in a marine protected area network

    KAUST Repository

    Berumen, Michael L.

    2012-02-01

    The use of marine protected area (MPA) networks to sustain fisheries and conserve biodiversity is predicated on two critical yet rarely tested assumptions. Individual MPAs must produce sufficient larvae that settle within that reserve\\'s boundaries to maintain local populations while simultaneously supplying larvae to other MPA nodes in the network that might otherwise suffer local extinction. Here, we use genetic parentage analysis to demonstrate that patterns of self-recruitment of two reef fishes (Amphiprion percula and Chaetodon vagabundus) in an MPA in Kimbe Bay, Papua New Guinea, were remarkably consistent over several years. However, dispersal from this reserve to two other nodes in an MPA network varied between species and through time. The stability of our estimates of self-recruitment suggests that even small MPAs may be self-sustaining. However, our results caution against applying optimization strategies to MPA network design without accounting for variable connectivity among species and over time. 2012 The Authors.

  13. Persistence of self-recruitment and patterns of larval connectivity in a marine protected area network.

    Science.gov (United States)

    Berumen, Michael L; Almany, Glenn R; Planes, Serge; Jones, Geoffrey P; Saenz-Agudelo, Pablo; Thorrold, Simon R

    2012-02-01

    The use of marine protected area (MPA) networks to sustain fisheries and conserve biodiversity is predicated on two critical yet rarely tested assumptions. Individual MPAs must produce sufficient larvae that settle within that reserve's boundaries to maintain local populations while simultaneously supplying larvae to other MPA nodes in the network that might otherwise suffer local extinction. Here, we use genetic parentage analysis to demonstrate that patterns of self-recruitment of two reef fishes (Amphiprion percula and Chaetodon vagabundus) in an MPA in Kimbe Bay, Papua New Guinea, were remarkably consistent over several years. However, dispersal from this reserve to two other nodes in an MPA network varied between species and through time. The stability of our estimates of self-recruitment suggests that even small MPAs may be self-sustaining. However, our results caution against applying optimization strategies to MPA network design without accounting for variable connectivity among species and over time.

  14. Bipolar and borderline patients display differential patterns of functional connectivity among resting state networks.

    Science.gov (United States)

    Das, Pritha; Calhoun, Vince; Malhi, Gin S

    2014-09-01

    Bipolar disorder (BD) and borderline personality (BPD) disorder share clinical features such as emotional lability and poor interpersonal functioning but the course of illness and treatment differs in these groups, which suggests that the underlying neurobiology of BD and BPD is likely to be different. Understanding the neural mechanisms behind the pathophysiology of BD and BPD will facilitate accurate diagnosis and inform the administration of targeted treatment. Since deficits in social cognition or emotion regulation or in the self-referential processing system can give rise to these clinical features, and impairment in these domains have been observed in both patient groups, functional connectivity within and between networks subserving these processes during resting was investigated using functional magnetic resonance imaging. Data were acquired from 16 patients with BD, 14 patients with BPD, and 13 healthy controls (HC) and functional connectivity strength was correlated with scores using the Difficulties in Emotion Regulation Scale. Functional network connectivity (FNC) patterns differentiated BD and BPD patients from HC. In BD, FNC was increased while in BPD it was decreased. In BD impaired FNC was evident primarily among networks involved in self-referential processing while in BPD it also involved the emotion regulatory network. Impaired FNC displayed an association with impulsivity in BPD and emotional clarity and emotional awareness in BD. This study shows that BD and BPD can perhaps be differentiated using resting state FNC approach and that the neural mechanisms underpinning overlapping symptoms discernibly differ between the groups. These findings provide a potential platform for elucidating the targeted effects of psychological interventions in both disorders.

  15. A Method for Using Adjacency Matrices to Analyze the Connections Students Make within and between Concepts: The Case of Linear Algebra

    Science.gov (United States)

    Selinski, Natalie E.; Rasmussen, Chris; Wawro, Megan; Zandieh, Michelle

    2014-01-01

    The central goals of most introductory linear algebra courses are to develop students' proficiency with matrix techniques, to promote their understanding of key concepts, and to increase their ability to make connections between concepts. In this article, we present an innovative method using adjacency matrices to analyze students'…

  16. A Method for Using Adjacency Matrices to Analyze the Connections Students Make within and between Concepts: The Case of Linear Algebra

    Science.gov (United States)

    Selinski, Natalie E.; Rasmussen, Chris; Wawro, Megan; Zandieh, Michelle

    2014-01-01

    The central goals of most introductory linear algebra courses are to develop students' proficiency with matrix techniques, to promote their understanding of key concepts, and to increase their ability to make connections between concepts. In this article, we present an innovative method using adjacency matrices to analyze students' interpretation…

  17. Recommendation Systems for Geoscience Data Portals Built by Analyzing Usage Patterns

    Science.gov (United States)

    Crosby, C.; Nandigam, V.; Baru, C.

    2009-04-01

    Since its launch five years ago, the National Science Foundation-funded GEON Project (www.geongrid.org) has been providing access to a variety of geoscience data sets such as geologic maps and other geographic information system (GIS)-oriented data, paleontologic databases, gravity and magnetics data and LiDAR topography via its online portal interface. In addition to data, the GEON Portal also provides web-based tools and other resources that enable users to process and interact with data. Examples of these tools include functions to dynamically map and integrate GIS data, compute synthetic seismograms, and to produce custom digital elevation models (DEMs) with user defined parameters such as resolution. The GEON portal built on the Gridsphere-portal framework allows us to capture user interaction with the system. In addition to the site access statistics captured by tools like Google Analystics which capture hits per unit time, search key words, operating systems, browsers, and referring sites, we also record additional statistics such as which data sets are being downloaded and in what formats, processing parameters, and navigation pathways through the portal. With over four years of data now available from the GEON Portal, this record of usage is a rich resource for exploring how earth scientists discover and utilize online data sets. Furthermore, we propose that this data could ultimately be harnessed to optimize the way users interact with the data portal, design intelligent processing and data management systems, and to make recommendations on algorithm settings and other available relevant data. The paradigm of integrating popular and commonly used patterns to make recommendations to a user is well established in the world of e-commerce where users receive suggestions on books, music and other products that they may find interesting based on their website browsing and purchasing history, as well as the patterns of fellow users who have made similar

  18. Pattern of species occurrence in detritus-based communities with variable connectivity

    Directory of Open Access Journals (Sweden)

    B. Bellisario

    2011-05-01

    Full Text Available Patterns and mechanisms of species occurrence in space and time are outstanding questions in community and conservation ecology. Much of the current debate focuses on randomness or non-randomness in the structuring process of ecological communities, and the extent to which local/deterministic or regional/stochastic processes may drive their composition. However, a categorical subdivision could be misleading, as community composition may be driven by a continuum between neutral- and niche-based processes. For instance, in spatially structured systems local processes may surpass regional processes over time or across space to derive non-random metacommunity structure, suggesting the filtering role of the environment in mediating the pattern of species occurrence. In this work we study the temporal composition of detritus-based communities, which are an essential component in many aquatic and terrestrial ecosystems. We used data about macroinvertebrate colonization of leaf detritus in different sites of a patchy-connected system, to measure the co-occurrence of species on the detrital resource and evaluate the role of the spatial configuration and the environmental variability in determining the community’s composition. Our results show the importance of considering the joint role of regional and local processes in mediating stochastic and deterministic mechanisms in species assemblage, with important outcomes from a conservation point of view.

  19. On the relevance of sophisticated structural annotations for disulfide connectivity pattern prediction.

    Directory of Open Access Journals (Sweden)

    Julien Becker

    Full Text Available Disulfide bridges strongly constrain the native structure of many proteins and predicting their formation is therefore a key sub-problem of protein structure and function inference. Most recently proposed approaches for this prediction problem adopt the following pipeline: first they enrich the primary sequence with structural annotations, second they apply a binary classifier to each candidate pair of cysteines to predict disulfide bonding probabilities and finally, they use a maximum weight graph matching algorithm to derive the predicted disulfide connectivity pattern of a protein. In this paper, we adopt this three step pipeline and propose an extensive study of the relevance of various structural annotations and feature encodings. In particular, we consider five kinds of structural annotations, among which three are novel in the context of disulfide bridge prediction. So as to be usable by machine learning algorithms, these annotations must be encoded into features. For this purpose, we propose four different feature encodings based on local windows and on different kinds of histograms. The combination of structural annotations with these possible encodings leads to a large number of possible feature functions. In order to identify a minimal subset of relevant feature functions among those, we propose an efficient and interpretable feature function selection scheme, designed so as to avoid any form of overfitting. We apply this scheme on top of three supervised learning algorithms: k-nearest neighbors, support vector machines and extremely randomized trees. Our results indicate that the use of only the PSSM (position-specific scoring matrix together with the CSP (cysteine separation profile are sufficient to construct a high performance disulfide pattern predictor and that extremely randomized trees reach a disulfide pattern prediction accuracy of [Formula: see text] on the benchmark dataset SPX[Formula: see text], which corresponds to

  20. Pulmonary vein flow pattern in children with bidirectional cavopulmonary connection or Fontan circuit

    Energy Technology Data Exchange (ETDEWEB)

    Shariat, Masoud; Yoo, Shi-Joon [Hospital for Sick Children, Department of Radiology, Toronto (Canada); Grosse-Wortmann, Lars; Windram, Jonathan [Hospital for Sick Children, Department of Cardiology, Toronto (Canada)

    2012-02-15

    Typical flow velocity profiles in the extraparenchymal pulmonary veins (PVs) demonstrate two major antegrade flow waves: a biphasic systolic wave (S), with S1 and S2 peaks and a monophasic early diastolic wave (D). Flow reversal during atrial systole (A) is common. There is agreement that the forward diastolic PV flow wave is caused by left ventricular relaxation with opening of the mitral valve. The origin of the PV systolic wave, however, remains a topic of debate. Some studies have suggested that the S wave is created by the relaxation of the left atrium and descent of the mitral valve plane. These studies have concluded that forces generated by the right ventricle (RV) have no effect on the S wave. Others suggest that the forward propagation of the right ventricular systolic pressure pulse is the major contributor to the S wave. To determine whether any part of the systolic wave of PV flow is dependent on forces created by the right ventricle. We assessed PV flow pattern, as obtained by cardiac MRI in 12 cases (39 pulmonary veins) with RV-independent pulmonary circulation (bidirectional cavopulmonary connection or Fontan circulation). Phase-contrast imaging of the PVs was performed on a 1.5-T MR scanner with velocity encoding set at 120 cm/s. We compared these flow patterns with those of a control group of ten children (15 pulmonary veins) who had RV-dependent pulmonary circulation and underwent CMR for other indications. In all PVs of children with RV-independent pulmonary circulation the flow curves showed a single systolic peak in early systole (S1) with the S2 peak consistently absent. PV flow pattern in the control group consistently showed distinct early and late systolic peaks. This study supports the concept that S2 is caused by forward propagation of the right ventricular systolic pressure pulse. It also demonstrates that the S1 is independent of the right ventricle. (orig.)

  1. Analyzing spatial patterns linked to the ecology of herbivores and their natural enemies in the soil

    Directory of Open Access Journals (Sweden)

    Raquel eCampos-Herrera

    2013-09-01

    Full Text Available Modern agricultural systems can benefit from the application of concepts and models from applied ecology. When understood, multitrophic interactions among plants, pests, diseases and their natural enemies can be exploited to increase crop production and reduce undesirable environmental impacts. Although the understanding of subterranean ecology is rudimentary compared to the perspective aboveground, technologies today vastly reduce traditional obstacles to studying cryptic communities. Here we emphasize advantages to integrating as much as possible the use of these methods in order to leverage the information gained from studying communities of soil organisms. PCR–based approaches to identify and quantify species (real time qPCR and new generation sequencing greatly expand the ability to investigate food web interactions because there is less need for wide taxonomic expertise within research programs. Improved methods to capture and measure volatiles in the soil atmosphere in situ make it possible to detect and study chemical cues that are critical to communication across trophic levels. The application of SADIE to directly assess rather than infer spatial patterns in belowground agroecosystems has improved the ability to characterize relationships between organisms in space and time. We review selected methodology and use of these tools and describe some of the ways they were integrated to study soil food webs in Florida citrus orchards with the goal of developing new biocontrol approaches.

  2. Analyzing Lifestyle and Consumption Pattern of Hire Groups under Product Service Systems in Taiwan

    Directory of Open Access Journals (Sweden)

    Jui-Che Tu

    2013-01-01

    Full Text Available This study explores the characteristics of rental goods, integrates the green concept in the design and development, and introduces the concept of product service into the rental consumption trend in Taiwan. This study takes the questionnaire survey to collect various opinions of the consumers to rental consumption and also classifies the Taiwanese consumers into five clusters based on the life styles, and the names of clusters are simple financial management cluster, environment and taste cluster, fashionable and flexible cluster, careful purchase cluster, and smart consumption cluster. Finally, conclusions are as follows. (1 The green consumption cognition and attitude of the consumers to the environmental goods can help to master the factor of green consumption property for developing the rental commodities. (2 The market segmentation of the rental consumption market can be enhanced by the variables of available life styles. (3 The applications with product service rental characteristics should take the opinion feedback of the consumers into the sustainable product development conditions and expand the service property of the product. (4 As the cost of cradle-to-cradle recycling pattern is high, the support and promotion of the government can help to construct the business model of product service rental consumption and develop the rental economy.

  3. Specification Representation and Test Case Reduction by Analyzing the Interaction Patterns in System Model

    Directory of Open Access Journals (Sweden)

    Ashish Kumari

    2012-01-01

    Full Text Available Extended Finite State Machine uses the formal description language to model the requirement specification of the system. The system models are frequently changed because of the specification changes. We can show the changes in specification by changing the model represented using finite state machine. To test the modified parts of the model the selective test generation techniques are used. However, the regression test suits still may be very large according to the size. In this paper, we have discussed the method whichdefine the test suits reduction and the requirement specification that used for testing the main system after the modifications in the requirements and implementation. Extended finite state machine uses the state transition diagram for representing the requirement specification. It shows how system changes states and action and variable used during each transition. After that data dependency andcontrol dependency are find out among the transitions of state transition diagram. After these dependencies we can find out the affecting and affected portion in the system introduced by the modification. The main condition is: “If two test cases generate same affecting and affected pattern, it means it is enough to implement only one test case rather than two.” So using this approach we can substantially reduce the size of original test suite.

  4. Geometry and Morphology of the Cosmic Web: Analyzing Spatial Patterns in the Universe

    CERN Document Server

    van de Weygaert, Rien; Jones, Bernard J T; Platen, Erwin

    2009-01-01

    We review the analysis of the Cosmic Web by means of an extensive toolset based on the use of Delaunay and Voronoi tessellations. The Cosmic Web is the salient and pervasive foamlike pattern in which matter has organized itself on scales of a few up to more than a hundred Megaparsec. First, we describe the Delaunay Tessellation Field Estimator (DTFE). The DTFE formalism is shown to recover the hierarchical nature and the anisotropic morphology of the cosmic matter distribution. The Multiscale Morphology Filter (MMF) uses the DTFE density field to extract the diverse morphological elements - filaments, sheets and clusters - on the basis of a ScaleSpace analysis which searches for these morphologies over a range of scales. Subsequently, we discuss the Watershed Voidfinder (WVF), which invokes the discrete watershed transform to identify voids in the cosmic matter distribution. The WVF is able to determine the location, size and shape of the voids. The watershed transform is also a key element in the SpineWeb an...

  5. Edge-mediated patterns of seed removal in experimentally connected and fragmented landscapes.

    Energy Technology Data Exchange (ETDEWEB)

    Craig, Michael, T.; Orrock, John, L.; Brudvig, Lars, A.

    2011-09-07

    While biological reserves remain central to biodiversity conservation, the amount of area available for terrestrial reserves may be inadequate for many taxa. Biodiversity spillover - the promotion of diversity in matrix areas surrounding reserves - might help address this shortfall in reserve area. However, the mechanistic underpinning of spillover remains uninvestigated. Two fundamental processes - seed dispersal and establishment - might generate plant biodiversity spillover. Here, we investigate the role of establishment in promoting spillover by assessing post-dispersal seed predation, a key component of establishment, in the matrix of a replicated, large-scale habitat fragmentation experiment, where spillover is relevated around patches connected by landscape corridors. Our results show that matrix seed predation may constrain the distance of this spillover effect by reducing establishment: seed removal was least at the matrix edge and increased further into the matrix. We found some support for matrix seed predation underpinning previously reported landscape-level variation in spillover. Of the three species we investigated, two showed evidence for elevated seed predation in the matrix surrounding the unconnected patches around which the lowest levels of spillover occur. However, seed predation did not explain connectivity-enhanced spillover, suggesting that seed dispersal likely drives this pattern. Management activities that increase seed deposition in the matrix may have beneficial effects via spillover. Our work also illustrates that matrix-mediated gradients in seed predation may be widespread, but likely vary depending upon matrix composition and the ecological system under consideration. In fragmented landscapes, this gradient could impact the distribution, abundance, and spread of plant species.

  6. Atomic force microscopy for analyzing metaphase chromosomes: comparison of AFM images with fluorescence labeling images of banding patterns.

    Science.gov (United States)

    Hoshi, Osamu; Ushiki, Tatsuo

    2014-01-01

    The combined use of fluorescence microscopy with atomic force microscopy (AFM) has been introduced to analyze the replication-banding patterns of human chromosomes. Human lymphocytes synchronized with excess thymidine are treated with 5-ethynyl-2'-deoxyuridine (EdU) during the late S phase. EdU-labeled DNA is detected in metaphase chromosomes using Alexa Fluor 488(®) azide, through the 1,3-dipolar cycloaddition reaction of organic azides with the terminal acetylene group of EdU. Chromosomes with EdU incorporated during the late S phase show a banding pattern similar to the G-banding pattern of normal human chromosomes. The comparison between the fluorescence and AFM image of the same chromosome indicates the presence of ridges and grooves in the chromatid arms, which correspond to G-positive and G-negative bands, respectively. This technique of EdU-labeled replication bands combined with AFM is useful to analyze the structure of chromosomes in relation to the banding pattern.

  7. Phylogeographic patterns of Merodon hoverflies in the Eastern Mediterranean region: revealing connections and barriers.

    Science.gov (United States)

    Ståhls, Gunilla; Vujić, Ante; Petanidou, Theodora; Cardoso, Pedro; Radenković, Snezana; Ačanski, Jelena; Pérez Bañón, Celeste; Rojo, Santos

    2016-04-01

    , patterns of phylogeographic structure deduced from haplotype connections and ISSR genome fingerprinting data revealed a few putative cases of human-mediated transfers of Merodon spp.

  8. Analyzing PACS Usage Patterns by Means of Process Mining: Steps Toward a More Detailed Workflow Analysis in Radiology.

    Science.gov (United States)

    Forsberg, Daniel; Rosipko, Beverly; Sunshine, Jeffrey L

    2016-02-01

    In this paper, statistical analysis and techniques from process mining are employed to analyze interaction patterns originating from radiologists reading medical images in a picture archiving and communication system (PACS). Event logs from 1 week of data, corresponding to 567 cases of single-view chest radiographs read by 14 radiologists, were analyzed. Statistical analysis showed that the numbers of commands and command types used by the radiologists per case only have a slightly positive correlation with the time to read a case (0.31 and 0.55, respectively). Further, one way ANOVA showed that the factors time of day, radiologist and specialty were significant for the number of commands per case, whereas radiologist was also significant for the number of command types, but with no significance of any of the factors on time to read. Applying process mining to the event logs of all users showed that a seemingly "simple" examination (single-view chest radiographs) can be associated with a highly complex interaction process. However, repeating the process discovery on each individual radiologist revealed that the initially discovered complex interaction process consists of one group of radiologists with individually well-structured interaction processes and a second smaller group of users with progressively more complex usage patterns. Future research will focus on metrics to describe derived interaction processes in order to investigate if one set of interaction patterns can be considered as more efficient than another set when reading radiological images in a PACS.

  9. Development of a Web GIS Application for Visualizing and Analyzing Community Out of Hospital Cardiac Arrest Patterns.

    Science.gov (United States)

    Semple, Hugh; Qin, Han; Sasson, Comilla

    2013-01-01

    Improving survival rates at the neighborhood level is increasingly seen as a priority for reducing overall rates of out-of-hospital cardiac arrest (OHCA) in the United States. Since wide disparities exist in OHCA rates at the neighborhood level, it is important for public health officials and residents to be able to quickly locate neighborhoods where people are at elevated risk for cardiac arrest and to target these areas for educational outreach and other mitigation strategies. This paper describes an OHCA web mapping application that was developed to provide users with interactive maps and data for them to quickly visualize and analyze the geographic pattern of cardiac arrest rates, bystander CPR rates, and survival rates at the neighborhood level in different U.S. cities. The data comes from the CARES Registry and is provided over a period spanning several years so users can visualize trends in neighborhood out-of-hospital cardiac arrest patterns. Users can also visualize areas that are statistical hot and cold spots for cardiac arrest and compare OHCA and bystander CPR rates in the hot and cold spots. Although not designed as a public participation GIS (PPGIS), this application seeks to provide a forum around which data and maps about local patterns of OHCA can be shared, analyzed and discussed with a view of empowering local communities to take action to address the high rates of OHCA in their vicinity.

  10. Connected shape-size pattern spectra for rotation and scale-invariant classification of gray-scale images

    NARCIS (Netherlands)

    Urbach, Erik R.; Roerdink, Jos B.T.M.; Wilkinson, Michael H.F.

    2007-01-01

    In this paper, we describe a multiscale and multishape morphological method for pattern-based analysis and classification of gray-scale images using connected operators. Compared with existing methods, which use structuring elements, our method has three advantages. First, in our method, the time ne

  11. Contrasting brain patterns of writing-related DTI parameters, fMRI connectivity, and DTI–fMRI connectivity correlations in children with and without dysgraphia or dyslexia

    Directory of Open Access Journals (Sweden)

    T.L. Richards

    2015-01-01

    Full Text Available Based on comprehensive testing and educational history, children in grades 4–9 (on average 12 years were diagnosed with dysgraphia (persisting handwriting impairment or dyslexia (persisting word spelling/reading impairment or as typical writers and readers (controls. The dysgraphia group (n = 14 and dyslexia group (n = 17 were each compared to the control group (n = 9 and to each other in separate analyses. Four brain region seed points (left occipital temporal gyrus, supramarginal gyrus, precuneus, and inferior frontal gyrus were used in these analyses which were shown in a metaanalysis to be related to written word production on four indicators of white matter integrity and fMRI functional connectivity for four tasks (self-guided mind wandering during resting state, writing letter that follows a visually displayed letter in alphabet, writing missing letter to create a correctly spelled real word, and planning for composing after scanning on topic specified by researcher. For those DTI indicators on which the dysgraphic group or dyslexic group differed from the control group (fractional anisotropy, relative anisotropy, axial diffusivity but not radial diffusivity, correlations were computed between the DTI parameter and fMRI functional connectivity for the two writing tasks (alphabet and spelling by seed points. Analyses, controlled for multiple comparisons, showed that (a the control group exhibited more white matter integrity than either the dysgraphic or dyslexic group; (b the dysgraphic and dyslexic groups showed more functional connectivity than the control group but differed in patterns of functional connectivity for task and seed point; and (c the dysgraphic and dyslexic groups showed different patterns of significant DTI–fMRI connectivity correlations for specific seed points and written language tasks. Thus, dysgraphia and dyslexia differ in white matter integrity, fMRI functional connectivity, and white matter–gray matter

  12. Extracting multiscale pattern information of fMRI based functional brain connectivity with application on classification of autism spectrum disorders.

    Directory of Open Access Journals (Sweden)

    Hui Wang

    Full Text Available We employed a multi-scale clustering methodology known as "data cloud geometry" to extract functional connectivity patterns derived from functional magnetic resonance imaging (fMRI protocol. The method was applied to correlation matrices of 106 regions of interest (ROIs in 29 individuals with autism spectrum disorders (ASD, and 29 individuals with typical development (TD while they completed a cognitive control task. Connectivity clustering geometry was examined at both "fine" and "coarse" scales. At the coarse scale, the connectivity clustering geometry produced 10 valid clusters with a coherent relationship to neural anatomy. A supervised learning algorithm employed fine scale information about clustering motif configurations and prevalence, and coarse scale information about intra- and inter-regional connectivity; the algorithm correctly classified ASD and TD participants with sensitivity of 82.8% and specificity of 82.8%. Most of the predictive power of the logistic regression model resided at the level of the fine-scale clustering geometry, suggesting that cellular versus systems level disturbances are more prominent in individuals with ASD. This article provides validation for this multi-scale geometric approach to extracting brain functional connectivity pattern information and for its use in classification of ASD.

  13. Extracting multiscale pattern information of fMRI based functional brain connectivity with application on classification of autism spectrum disorders.

    Science.gov (United States)

    Wang, Hui; Chen, Chen; Fushing, Hsieh

    2012-01-01

    We employed a multi-scale clustering methodology known as "data cloud geometry" to extract functional connectivity patterns derived from functional magnetic resonance imaging (fMRI) protocol. The method was applied to correlation matrices of 106 regions of interest (ROIs) in 29 individuals with autism spectrum disorders (ASD), and 29 individuals with typical development (TD) while they completed a cognitive control task. Connectivity clustering geometry was examined at both "fine" and "coarse" scales. At the coarse scale, the connectivity clustering geometry produced 10 valid clusters with a coherent relationship to neural anatomy. A supervised learning algorithm employed fine scale information about clustering motif configurations and prevalence, and coarse scale information about intra- and inter-regional connectivity; the algorithm correctly classified ASD and TD participants with sensitivity of 82.8% and specificity of 82.8%. Most of the predictive power of the logistic regression model resided at the level of the fine-scale clustering geometry, suggesting that cellular versus systems level disturbances are more prominent in individuals with ASD. This article provides validation for this multi-scale geometric approach to extracting brain functional connectivity pattern information and for its use in classification of ASD.

  14. State-Dependent Changes of Connectivity Patterns and Functional Brain Network Topology in Autism Spectrum Disorder

    Science.gov (United States)

    Barttfeld, Pablo; Wicker, Bruno; Cukier, Sebastian; Navarta, Silvana; Lew, Sergio; Leiguarda, Ramon; Sigman, Mariano

    2012-01-01

    Anatomical and functional brain studies have converged to the hypothesis that autism spectrum disorders (ASD) are associated with atypical connectivity. Using a modified resting-state paradigm to drive subjects' attention, we provide evidence of a very marked interaction between ASD brain functional connectivity and cognitive state. We show that…

  15. Analyzing a problem-solution pattern in the transcription of a conversation: suggestions for the ELF classroom

    Directory of Open Access Journals (Sweden)

    Navas Brenes, César A.

    2005-12-01

    Full Text Available This paper analyzes a problem-solution pattern shown in the transcription of a conversation. This analysis is based on a conversation that has been elicited from three native speakers of English. These speakers were given a topic that dealt with the problem of children being constantly exposed to violent video games. As a result, the writer recorded an oral text that contains several elements related to a problem-solution pattern such as the main issue, opinions, personal examples, possible solutions, and the evaluation of these solutions. The writer analyzed this pattern in terms of discourse analysis using idea units from the transcription. Moreover, the writer will point out how appropriate this transcription is for preparing teaching tasks for the EFL classroom. Este artículo analiza el patrón estructural de la solución de un problema evidente en la transcripción de una conversación. El análisis esta basado en un diálogo obtenido de tres hablantes nativos de la lengua inglesa. El autor suministró a dichas personas un tema relacionado con el problema de la exposición de niños al contenido violento de los juegos de video. Como resultado, el escritor obtuvo una grabación del texto oral que contiene varios elementos relacionados con el patrón estructural de la solución de un problema. Algunos de estos elementos son el problema principal, opiniones, ejemplos personales, soluciones viables al problema, y la evaluación de dichas soluciones. El autor analizó algunas líneas de la transcripción con la ayuda de algunos conceptos relacionados con el análisis del discurso. Cabe destacar que el uso de tales trascripciones es muy apropiado en la preparación de actividades para una clase de inglés como lengua extranjera.

  16. On Pattern Separating Function in a Two-Layered Random Nerve Net with Feedforward Inhibitory Connections

    Institute of Scientific and Technical Information of China (English)

    ToyoshiTorioka; 汪嘉业

    1989-01-01

    In this paper, we derive a theory for investigating the pattern separating function in the nerve net. Then, we consider some effects of the stochastic parameters constructing the nerve net, firing rates of the second layer and input patterns on the pattern separating faction through the theory. As a result ,we reveal that a nerve net excellent in pattern separating fuuction is obtained when the stochastic parameters are selected properly . We also shew that the pattern separating function is enhanced by controlling the firing rate of the second layer to a small value. Furthermore, the input patterns are separated large|y when the firing rates of them are latge.

  17. More consistently altered connectivity patterns for cerebellum and medial temporal lobes than for amygdala and striatum in schizophrenia

    Directory of Open Access Journals (Sweden)

    Henning ePeters

    2016-02-01

    Full Text Available Background: Brain architecture can be divided into a cortico-thalamic system and modulatory ‘subcortical-cerebellar’ systems containing key structures such as striatum, medial temporal lobes (MTLs, amygdala, and cerebellum. Subcortical-cerebellar systems are known to be altered in schizophrenia. In particular, intrinsic functional brain connectivity (iFC between these systems has been consistently demonstrated in patients. While altered connectivity is known for each subcortical-cerebellar system separately, it is unknown whether subcortical-cerebellar systems’ connectivity patterns with the cortico-thalamic system are comparably altered across systems, i.e., if separate subcortical-cerebellar systems’ connectivity patterns are consistent across patients. Methods: To investigate this question, 18 patients with schizophrenia (3 unmedicated, 15 medicated with atypical antipsychotics and 18 healthy controls were assessed by resting-state functional magnetic resonance imaging (fMRI. Independent component analysis of fMRI data revealed cortical intrinsic brain networks (NWs with time courses representing proxies for cortico-thalamic system activity. Subcortical-cerebellar systems’ activity was represented by fMRI-based time courses of selected regions-of-interest (ROIs (i.e., striatum, MTL, amygdala, cerebellum. Correlation analysis among ROI- and NWs-time courses yielded individual connectivity matrices (i.e. connectivity between NW and ROIs (allROIs-NW, separateROI-NW, only NWs (NWs-NWs, and only ROIs (allROIs-allROIs as main outcome measures, which were classified by support-vector-machine-based leave-one-out cross-validation. Differences in classification accuracy were statistically evaluated for consistency across subjects and systems. Results: Correlation matrices based on allROIs-NWs yielded 91% classification accuracy, which was significantly superior to allROIs-allROIs and NWs-NWs (56% and 74%, respectively. Considering separate

  18. On Pattern Separating Function in a Two-Layered Random Nerve Net with Feedforward Inhibitory Connections

    Institute of Scientific and Technical Information of China (English)

    ToyoshiTorioka; 汪嘉业

    1989-01-01

    In this paper,we derive a theory for investigating the pattern separating function in the nerve net ,then,we consider some effects of the stochastic parameters constructing the nerve net,firing rates of the second layer and input patterns on the pattern separating function through the stochastic parameters are selected proerly.we also show that the pattern separating function is enhanced by controlling the firing rate of the second layer to a small value.Furthermore,the input patterns are separated largely when the firing rates of them are large.

  19. Measures for brain connectivity analysis: nodes centrality and their invariant patterns

    Science.gov (United States)

    Silva, Laysa Mayra Uchôa da; Baltazar, Carlos Arruda; Silva, Camila Aquemi; Ribeiro, Mauricio Watanabe; Aratanha, Maria Adelia Albano de; Deolindo, Camila Sardeto; Rodrigues, Abner Cardoso; Machado, Birajara Soares

    2017-01-01

    The high dynamical complexity of the brain is related to its small-world topology, which enable both segregated and integrated information processing capabilities. Several measures of connectivity estimation have already been employed to characterize functional brain networks from multivariate electrophysiological data. However, understanding the properties of each measure that lead to a better description of the real topology and capture the complex phenomena present in the brain remains challenging. In this work we compared four nonlinear connectivity measures and show that each method characterizes distinct features of brain interactions. The results suggest an invariance of global network parameters from different behavioral states and that more complete description may be reached considering local features, independently of the connectivity measure employed. Our findings also point to future perspectives in connectivity studies that combine distinct and complementary dependence measures in assembling higher dimensions manifolds.

  20. Comparison of contourlet transform and gray level co-occurrence matrix for analyzing cell-scattered patterns

    Science.gov (United States)

    Zhang, Jun; Wang, Gang; Feng, Yuanming; Sa, Yu

    2016-08-01

    Distribution of scattered image patterns hinges on morphological and optical characteristics of cells. This paper applied a numerical method to simulate scattered images of real cell morphologies, which were reconstructed from confocal image stacks dyed by fluorescent stains. Two approaches, contourlet transform (CT) and gray level co-occurrence matrix (GLCM), were then used to analyze the simulated scattered images. The results showed that features extracted using GLCM contained more information than those extracted using CT. Higher classification accuracy could be achieved with a single GLCM parameter than CT and GLCM could achieve higher accuracy with fewer parameters than CT when using multiple parameters. Meanwhile, GLCM requires less computational cost. Thus, GLCM is more suitable and efficient than CT for the analysis of cell-scattered images.

  1. Group-ICA model order highlights patterns of functional brain connectivity

    Directory of Open Access Journals (Sweden)

    Ahmed eAbou Elseoud

    2011-06-01

    Full Text Available Resting-state networks (RSNs can be reliably and reproducibly detected using independent component analysis (ICA at both individual subject and group levels. Altering ICA dimensionality (model order estimation can have a significant impact on the spatial characteristics of the RSNs as well as their parcellation into sub-networks. Recent evidence from several neuroimaging studies suggests that the human brain has a modular hierarchical organization which resembles the hierarchy depicted by different ICA model orders. We hypothesized that functional connectivity between-group differences measured with ICA might be affected by model order selection. We investigated differences in functional connectivity using so-called dual-regression as a function of ICA model order in a group of unmedicated seasonal affective disorder (SAD patients compared to normal healthy controls. The results showed that the detected disease-related differences in functional connectivity alter as a function of ICA model order. The volume of between-group differences altered significantly as a function of ICA model order reaching maximum at model order 70 (which seems to be an optimal point that conveys the largest between-group difference then stabilized afterwards. Our results show that fine-grained RSNs enable better detection of detailed disease-related functional connectivity changes. However, high model orders show an increased risk of false positives that needs to be overcome. Our findings suggest that multilevel ICA exploration of functional connectivity enables optimization of sensitivity to brain disorders.

  2. Modelling water and sediment connectivity patterns in a semi-arid landscape

    Energy Technology Data Exchange (ETDEWEB)

    Cammeraat, L. H.; Beek, L. P. H. van; Dooms, T.

    2009-07-01

    Desertification is a major threat in SE Spain and mitigation strategies are required to reduce the adverse effect of water-induced erosion on soil production potential. Severity of soil erosion depends on local runoff response and the connectivity of pathways of water and sediment at different spatial scales. We investigated the connectivity between sources and sinks on semi-natural slopes by means of a semi-distributed model that delineated Hydrological response Units (HRUs) on the basis of physiographic characteristics. The model was calibrated with information at the plot, hill slope and sub-catchment scale covering the period 1995-2008 and validated against larger events that connected the semi-natural sub-catchment with the underlying cultivated slopes. (Author) 12 refs.

  3. Jubilite: A 4-,8-connected Cubic Structural Pattern in Space Group Pm3

    Directory of Open Access Journals (Sweden)

    Eduardo A. Castro

    2005-05-01

    Full Text Available Abstract: In the course of investigating structural modifications of the 3-,4-connected net known as the Pt3O4 structure-type (waserite, a novel 4-,8-connected structure-type was discovered. This lattice is generated by replacing the 3-connected trigonal planar vertices of the Pt3O4 structure-type with 4-connected tetrahedral vertices, to achieve a structure which possesses a generic empirical formula of JK6L8. In such a topological modification, the four 3-fold axes of the parent cubic, Pm3n, Pt3O4 structure-type are retained. Thus the 4-connected tetrahedral vertices are oriented so as to preserve cubic symmetry in the resulting Pm3, JK6L8 (jubilite lattice. The unit cell contains a single 8-connected cubecentered vertex, six 4-connected distorted square planar vertices and eight 4-connected distorted tetrahedral vertices. It is a Wellsean structure with a Wells point symbol given by (4166484(42826(43838 and a Schläfli symbol of (53/4, 4.2667. This latter index reveals a decrease in the lattice’s polygonality and concomitant increase in the connectivity through the transformation from waserite to jubilite. The topology of the parent waserite lattice (Pt3O4 corresponds to that of the Catalan structures with the Wells point symbol (843(834, which has the Schläfli symbol (8, 3.4285. Finally, it can be seen that a sequence of structure-types starting with waserite (Pt3O4 and moving to jubilite (JK6L8 and finally to fluorite (CaF2 represents a continuous crystallographic structural transformation in which the symmetry and topology undergo concomitant changes from one structure-type (waserite to the other structure-types. The topology of the fluorite lattice, represented by the Wells point symbol (424(462, and the Schläfli symbol (4, 51/3, indicates a discontinuous topological transformation from the intermediate jubilite lattice; like the discontinuous topological transformation from Pt3O4 to JK6L8; in which the

  4. Connectivity and Dispersal Patterns of Protected Biogenic Reefs: Implications for the Conservation of Modiolus modiolus (L. in the Irish Sea.

    Directory of Open Access Journals (Sweden)

    Kate Gormley

    Full Text Available Biogenic reefs created by Modiolus modiolus (Linnaeus, 1758 (horse mussel reefs are marine habitats which support high levels of species biodiversity and provide valuable ecosystem services. Currently, M. modiolus reefs are listed as a threatened and/or declining species and habitat in all OSPAR regions and thus are highlighted as a conservation priority under the EU Marine Strategy Framework Directive (MSFD. Determining patterns of larval dispersal and genetic connectivity of remaining horse mussel populations can inform management efforts and is a critical component of effective marine spatial planning (MSP. Larval dispersal patterns and genetic structure were determined for several M. modiolus bed populations in the Irish Sea including those in Wales (North Pen Llŷn, Isle of Man (Point of Ayre and Northern Ireland (Ards Peninsula and Strangford Lough. Simulations of larval dispersal suggested extant connectivity between populations within the Irish Sea. Results from the genetic analysis carried out using newly developed microsatellite DNA markers were consistent with those of the biophysical model. Results indicated moderately significant differentiation between the Northern Ireland populations and those in the Isle of Man and Wales. Simulations of larval dispersal over a 30 day pelagic larval duration (PLD suggest that connectivity over a spatial scale of 150km is possible between some source and sink populations. However, it appears unlikely that larvae from Northern Ireland will connect directly with sites on the Llŷn or Isle of Man. It also appears unlikely that larvae from the Llŷn connect directly to any of the other sites. Taken together the data establishes a baseline for underpinning management and conservation of these important and threatened marine habitats in the southern part of the known range.

  5. Modelling water and sediment connectivity patterns in a semi-arid landscape

    NARCIS (Netherlands)

    Cammeraat, L.H.; van Beek, L.P.H.; Dooms, T.; Romero-Díaz, A.; Belmonte Serrato, F.; Alonso Sarria, F.; López Bermúdez, F.

    2009-01-01

    Desertification is a major threat in SE Spain and mitigation strategies are required to reduce the adverse effect of water-induced erosion on soil production potential. Severity of soil erosion depends on local runoff response and the connectivity of pathways of water and sediment at different spati

  6. Epigenetic Patterns Modulate the Connection between Developmental Dynamics of Parenting and Offspring Psychosocial Adjustment

    Science.gov (United States)

    Naumova, Oksana Yu.; Hein, Sascha; Suderman, Matthew; Barbot, Baptiste; Lee, Maria; Raefski, Adam; Dobrynin, Pavel V.; Brown, Pamela J.; Szyf, Moshe; Luthar, Suniya S.; Grigorenko, Elena L.

    2016-01-01

    This study attempted to establish and quantify the connections between parenting, offspring psychosocial adjustment, and the epigenome. The participants, 35 African American young adults (19 females and 16 males; age = 17-29.5 years), represented a subsample of a 3-wave longitudinal 15-year study on the developmental trajectories of low-income…

  7. Effect of Cues to Increase Sound Pressure Level on Respiratory Kinematic Patterns during Connected Speech

    Science.gov (United States)

    Huber, Jessica E.

    2007-01-01

    Purpose: This study examined the response of the respiratory system to 3 cues used to elicit increased vocal loudness to determine whether the effects of cueing, shown previously in sentence tasks, were present in connected speech tasks and to describe differences among tasks. Method: Fifteen young men and 15 young women produced a 2-paragraph…

  8. Differentiated effective connectivity patterns of the executive control network in progressive MCI: a potential biomarker for predicting AD.

    Science.gov (United States)

    Cai, Suping; Peng, Yanlin; Chong, Tao; Zhang, Yun; von Deneen, Karen M; Huang, Liyu; Aibl Research Group

    2017-03-09

    Mild cognitive impairment (MCI) is often a transitional state between normal aging and Alzheimer's disease (AD). When observed longitudinally, some MCI patients convert to AD, while a considerable portion either remain MCI or revert to a normal functioning state. This divergence has provided some enlightenment on a potential biomarker be represented in the resting state brain activities of MCI patients with different post-hoc labels. Recent studies have shown impaired executive functions, other than typically explicated memory impairment with AD/MCI patients. This observation raises the question that whether or not the executive control network (ECN) was impaired, as which pivotally supports the central executive functions. Given the fact that effective connectivity is a sufficient index in detecting resting brain abnormalities in AD/MCI, the current study specifically asks a question whether the effective connectivity patterns are differentiated in MCI patients with different post-hoc labels. We divided the MCI subjects into three groups depending on their progressive state obtained longitudinally: 1) 15 MCI-R subjects: MCI reverted to the normal functioning state and stabilized to the normal state in 24 months; 2) 35 MCI-S subjects: MCI patients maintained this disease in a stable state for 24 months; 3) 22 MCI-P subjects: MCI progressed to AD and stabilized to AD in 24 months, and 4) 39 age-matched normal control subjects (NC). We conducted a Granger causality analysis after identifying the core nodes of ECN in all of the subjects using Independent Component Analysis. Our findings revealed that different MCI groups presented different effective connectivity patterns within the ECN compared to the NC group. Specifically, (1) dorsolateral prefrontal cortex (dLPFC) and medial prefrontal cortex (mPFC) were the core nodes in the ECN network that exhibited different connecting patterns; (2) an effective connection circuit "R.dLPFC right caudate Left thalamus

  9. Evolutionary plasticity of habenular asymmetry with a conserved efferent connectivity pattern.

    Directory of Open Access Journals (Sweden)

    Aldo Villalón

    Full Text Available The vertebrate habenulae (Hb is an evolutionary conserved dorsal diencephalic nuclear complex that relays information from limbic and striatal forebrain regions to the ventral midbrain. One key feature of this bilateral nucleus is the presence of left-right differences in size, cytoarchitecture, connectivity, neurochemistry and/or gene expression. In teleosts, habenular asymmetry has been associated with preferential innervation of left-right habenular efferents into dorso-ventral domains of the midbrain interpeduncular nucleus (IPN. However, the degree of conservation of this trait and its relation to the structural asymmetries of the Hb are currently unknown. To address these questions, we performed the first systematic comparative analysis of structural and connectional asymmetries of the Hb in teleosts. We found striking inter-species variability in the overall shape and cytoarchitecture of the Hb, and in the frequency, strength and to a lesser degree, laterality of habenular volume at the population level. Directional asymmetry of the Hb was either to the left in D. rerio, E. bicolor, O. latipes, P. reticulata, B. splendens, or to the right in F. gardneri females. In contrast, asymmetry was absent in P. scalare and F. gardneri males at the population level, although in these species the Hb displayed volumetric asymmetries at the individual level. Inter-species variability was more pronounced across orders than within a single order, and coexisted with an overall conserved laterotopic representation of left-right habenular efferents into dorso-ventral domains of the IPN. These results suggest that the circuit design involving the Hb of teleosts promotes structural flexibility depending on developmental, cognitive and/or behavioural pressures, without affecting the main midbrain connectivity output, thus unveiling a key conserved role of this connectivity trait in the function of the circuit. We propose that ontogenic plasticity in habenular

  10. Analyzing the spatial patterns and drivers of ecosystem services in rapidly urbanizing Taihu Lake Basin of China

    Science.gov (United States)

    Ai, Junyong; Sun, Xiang; Feng, Lan; Li, Yangfan; Zhu, Xiaodong

    2015-09-01

    Quantifying and mapping the distribution patterns of ecosystem services can help to ascertain which services should be protected and where investments should be directed to improve synergies and reduce tradeoffs. Moreover, the indicators of urbanization that affect the provision of ecosystem services must be identified to determine which approach to adopt in formulating policies related to these services. This paper presents a case study that maps the distribution of multiple ecosystem services and analyzes the ways in which they interact. The relationship between the supply of ecosystem services and the socio-economic development in the Taihu Lake Basin of eastern China is also revealed. Results show a significant negative relationship between crop production and tourism income ( p<0.005) and a positive relationship between crop production, nutrient retention, and carbon sequestration ( p<0.005). The negative effects of the urbanization process on providing and regulating services are also identified through a comparison of the ecosystem services in large and small cities. Regression analysis was used to compare and elucidate the relative significance of the selected urbanization factors to ecosystem services. The results indicate that urbanization level is the most substantial factor inversely correlated with crop production ( R 2 = 0.414) and nutrient retention services ( R 2 = 0.572). Population density is the most important factor that negatively affects carbon sequestration ( R 2 = 0.447). The findings of this study suggest the potential relevance of ecosystem service dynamics to urbanization management and decision making.

  11. [Landscape pattern change of Dongzhai Harbour mangrove, South China analyzed with a patch-based method and its driving forces].

    Science.gov (United States)

    Huang, Xing; Xin, Kun; Li, Xiu-zhen; Wang, Xue-ping; Ren, Lin-jing; Li, Xi-zhi; Yan, Zhong-zheng

    2015-05-01

    According to the interpreted results of three satellite images of Dongzhai Harbour obtained in 1988, 1998 and 2009, the changes of landscape pattern and the differences of its driving forces of mangrove forest in Dongzhai Harbour were analyzed with a patch-based method on spatial distribution dynamics. The results showed that the areas of mangrove forest in 1988, 1998 and 2009 were 1809.4, 1738.7 and 1608.2 hm2 respectively, which presented a trend of decrease with enhanced degree of landscape fragmentation. The transformations among different landscape types indicated that the mangrove, agricultural land and forest land were mainly changed into built-up land and aquaculture pond. The statistical results obtained from three different methods, i.e., accumulative counting, percentage counting and main transformation route counting, showed that natural factors were the main reason for the changes of patch number, responsible for 58.6%, 72.2% and 72.1% of patch number change, respectively, while the percentages of patch area change induced by human activities were 70.4%, 70.3% and 76.4%, respectively, indicating that human activities were the primary factors of the change of patch areas.

  12. Genetic dyslexia risk variant is related to neural connectivity patterns underlying phonological awareness in children.

    Science.gov (United States)

    Skeide, Michael A; Kirsten, Holger; Kraft, Indra; Schaadt, Gesa; Müller, Bent; Neef, Nicole; Brauer, Jens; Wilcke, Arndt; Emmrich, Frank; Boltze, Johannes; Friederici, Angela D

    2015-09-01

    Phonological awareness is the best-validated predictor of reading and spelling skill and therefore highly relevant for developmental dyslexia. Prior imaging genetics studies link several dyslexia risk genes to either brain-functional or brain-structural factors of phonological deficits. However, coherent evidence for genetic associations with both functional and structural neural phenotypes underlying variation in phonological awareness has not yet been provided. Here we demonstrate that rs11100040, a reported modifier of SLC2A3, is related to the functional connectivity of left fronto-temporal phonological processing areas at resting state in a sample of 9- to 12-year-old children. Furthermore, we provide evidence that rs11100040 is related to the fractional anisotropy of the arcuate fasciculus, which forms the structural connection between these areas. This structural connectivity phenotype is associated with phonological awareness, which is in turn associated with the individual retrospective risk scores in an early dyslexia screening as well as to spelling. These results suggest a link between a dyslexia risk genotype and a functional as well as a structural neural phenotype, which is associated with a phonological awareness phenotype. The present study goes beyond previous work by integrating genetic, brain-functional and brain-structural aspects of phonological awareness within a single approach. These combined findings might be another step towards a multimodal biomarker for developmental dyslexia.

  13. Resting-state functional connectivity patterns predict Chinese word reading competency.

    Directory of Open Access Journals (Sweden)

    Xiaosha Wang

    Full Text Available Resting-state functional connectivity (RSFC offers a novel approach to reveal the temporal synchronization of functionally related brain regions. Recent studies have identified several RSFCs whose strength was associated with reading competence in alphabetic languages. In the present study, we examined the role of intrinsic functional relations for reading a non-alphabetic language--Chinese--by correlating RSFC maps of nine Chinese reading-related seed regions and reaction time in the single-character reading task. We found that Chinese reading efficiency was positively correlated with the connection between left inferior occipital gyrus and left superior parietal lobule, between right posterior fusiform gyrus and right superior parietal lobule, and between left inferior temporal gyrus and left inferior parietal lobule. These results could not be attributed to inter-individual differences arising from the peripheral processes of the reading task such as visual input detection and articulation. The observed RSFC-reading correlation relationships are discussed in the framework of Chinese character reading, including visuospatial analyses and semantic/phonological processes.

  14. Functional connectivity-based signatures of schizophrenia revealed by multiclass pattern analysis of resting-state fMRI from schizophrenic patients and their healthy siblings

    Directory of Open Access Journals (Sweden)

    Yu Yang

    2013-02-01

    Full Text Available Abstract Background Recently, a growing number of neuroimaging studies have begun to investigate the brains of schizophrenic patients and their healthy siblings to identify heritable biomarkers of this complex disorder. The objective of this study was to use multiclass pattern analysis to investigate the inheritable characters of schizophrenia at the individual level, by comparing whole-brain resting-state functional connectivity of patients with schizophrenia to their healthy siblings. Methods Twenty-four schizophrenic patients, twenty-five healthy siblings and twenty-two matched healthy controls underwent the resting-state functional Magnetic Resonance Imaging (rs-fMRI scanning. A linear support vector machine along with principal component analysis was used to solve the multi-classification problem. By reconstructing the functional connectivities with high discriminative power, three types of functional connectivity-based signatures were identified: (i state connectivity patterns, which characterize the nature of disruption in the brain network of patients with schizophrenia; (ii trait connectivity patterns, reflecting shared connectivities of dysfunction in patients with schizophrenia and their healthy siblings, thereby providing a possible neuroendophenotype and revealing the genetic vulnerability to develop schizophrenia; and (iii compensatory connectivity patterns, which underlie special brain connectivities by which healthy siblings might compensate for an increased genetic risk for developing schizophrenia. Results Our multiclass pattern analysis achieved 62.0% accuracy via leave-one-out cross-validation (p  Conclusions Based on our experimental results, we saw some indication of differences in functional connectivity patterns in the healthy siblings of schizophrenic patients compared to other healthy individuals who have no relations with the patients. Our preliminary investigation suggested that the use of resting-state functional

  15. Phylogeographic pattern of the striped snakehead, Channa striata in Sundaland: ancient river connectivity, geographical and anthropogenic signatures [corrected].

    Science.gov (United States)

    Tan, Min Pau; Jamsari, Amirul Firdaus Jamaluddin; Siti Azizah, Mohd Nor

    2012-01-01

    A phylogeographic study of an economically important freshwater fish, the striped snakehead, Channa striata in Sundaland was carried out using data from mtDNA ND5 gene target to elucidate genetic patterning. Templates obtained from a total of 280 individuals representing 24 sampling sites revealed 27 putative haplotypes. Three distinct genetic lineages were apparent; 1)northwest Peninsular Malaysia, 2)southern Peninsular, east Peninsular, Sumatra and SW (western Sarawak) and 3) central west Peninsular and Malaysian Borneo (except SW). Genetic structuring between lineages showed a significant signature of natural geographical barriers that have been acting as effective dividers between these populations. However, genetic propinquity between the SW and southern Peninsular and east Peninsular Malaysia populations was taken as evidence of ancient river connectivity between these regions during the Pleistocene epoch. Alternatively, close genetic relationship between central west Peninsular Malaysia and Malaysian Borneo populations implied anthropogenic activities. Further, haplotype sharing between the east Peninsular Malaysia and Sumatra populations revealed extraordinary migration ability of C. striata (>500 km) through ancient connectivity. These results provide interesting insights into the historical and contemporary landscape arrangement in shaping genetic patterns of freshwater species in Sundaland.

  16. Phylogeographic pattern of the striped snakehead, Channa striata in Sundaland: ancient river connectivity, geographical and anthropogenic signatures [corrected].

    Directory of Open Access Journals (Sweden)

    Min Pau Tan

    Full Text Available A phylogeographic study of an economically important freshwater fish, the striped snakehead, Channa striata in Sundaland was carried out using data from mtDNA ND5 gene target to elucidate genetic patterning. Templates obtained from a total of 280 individuals representing 24 sampling sites revealed 27 putative haplotypes. Three distinct genetic lineages were apparent; 1northwest Peninsular Malaysia, 2southern Peninsular, east Peninsular, Sumatra and SW (western Sarawak and 3 central west Peninsular and Malaysian Borneo (except SW. Genetic structuring between lineages showed a significant signature of natural geographical barriers that have been acting as effective dividers between these populations. However, genetic propinquity between the SW and southern Peninsular and east Peninsular Malaysia populations was taken as evidence of ancient river connectivity between these regions during the Pleistocene epoch. Alternatively, close genetic relationship between central west Peninsular Malaysia and Malaysian Borneo populations implied anthropogenic activities. Further, haplotype sharing between the east Peninsular Malaysia and Sumatra populations revealed extraordinary migration ability of C. striata (>500 km through ancient connectivity. These results provide interesting insights into the historical and contemporary landscape arrangement in shaping genetic patterns of freshwater species in Sundaland.

  17. Alterations of Intrinsic Brain Connectivity Patterns in Depression and Bipolar Disorders: A Critical Assessment of Magnetoencephalography-Based Evidence

    Science.gov (United States)

    Alamian, Golnoush; Hincapié, Ana-Sofía; Combrisson, Etienne; Thiery, Thomas; Martel, Véronique; Althukov, Dmitrii; Jerbi, Karim

    2017-01-01

    Despite being the object of a thriving field of clinical research, the investigation of intrinsic brain network alterations in psychiatric illnesses is still in its early days. Because the pathological alterations are predominantly probed using functional magnetic resonance imaging (fMRI), many questions about the electrophysiological bases of resting-state alterations in psychiatric disorders, particularly among mood disorder patients, remain unanswered. Alongside important research using electroencephalography (EEG), the specific recent contributions and future promise of magnetoencephalography (MEG) in this field are not fully recognized and valued. Here, we provide a critical review of recent findings from MEG resting-state connectivity within major depressive disorder (MDD) and bipolar disorder (BD). The clinical MEG resting-state results are compared with those previously reported with fMRI and EEG. Taken together, MEG appears to be a promising but still critically underexploited technique to unravel the neurophysiological mechanisms that mediate abnormal (both hyper- and hypo-) connectivity patterns involved in MDD and BD. In particular, a major strength of MEG is its ability to provide source-space estimations of neuromagnetic long-range rhythmic synchronization at various frequencies (i.e., oscillatory coupling). The reviewed literature highlights the relevance of probing local and interregional rhythmic synchronization to explore the pathophysiological underpinnings of each disorder. However, before we can fully take advantage of MEG connectivity analyses in psychiatry, several limitations inherent to MEG connectivity analyses need to be understood and taken into account. Thus, we also discuss current methodological challenges and outline paths for future research. MEG resting-state studies provide an important window onto perturbed spontaneous oscillatory brain networks and hence supply an important complement to fMRI-based resting-state measurements in

  18. Statistical traces of long-term memories stored in strengths and patterns of synaptic connections

    OpenAIRE

    2011-01-01

    Learning and long-term memory rely on plasticity of neural circuits. In adult cerebral cortex plasticity can result from potentiation and depression of synaptic strengths and structural reorganization of circuits through growth and retraction of dendritic spines. By analyzing 166 distributions of spine head volumes and spine lengths from mouse, rat, monkey, and human brains, we determine the “generalized cost” of dendritic spines. This cost universally depends on spine shape, i.e. the depende...

  19. On the quantization of time-varying phase synchrony patterns into distinct functional connectivity microstates (FCμstates) in a multi-trial visual ERP paradigm.

    Science.gov (United States)

    Dimitriadis, S I; Laskaris, N A; Tzelepi, A

    2013-07-01

    The analysis of functional brain connectivity has been supported by various techniques encompassing spatiotemporal interactions between distinct areas and enabling the description of network organization. Different brain states are known to be associated with specific connectivity patterns. We introduce here the concept of functional connectivity microstates (FCμstates) as short lasting connectivity patterns resulting from the discretization of temporal variations in connectivity and mediating a parsimonious representation of coordinated activity in the brain. Modifying a well-established framework for mining brain dynamics, we show that a small sized repertoire of FCμstates can be derived so as to encapsulate both the inter-subject and inter-trial response variability and further provide novel insights into cognition. The main practical advantage of our approach lies in the fact that time-varying connectivity analysis can be simplified significantly by considering each FCμstate as prototypical connectivity pattern, and this is achieved without sacrificing the temporal aspects of dynamics. Multi-trial datasets from a visual ERP experiment were employed so as to provide a proof of concept, while phase synchrony was emphasized in the description of connectivity structure. The power of FCμstates in knowledge discovery is demonstrated through the application of network topology descriptors. Their time-evolution and association with event-related responses is explored.

  20. Using the "K[subscript 5]Connected Cognition Diagram" to Analyze Teachers' Communication and Understanding of Regions in Three-Dimensional Space

    Science.gov (United States)

    Moore-Russo, Deborah; Viglietti, Janine M.

    2012-01-01

    This paper reports on a study that introduces and applies the "K[subscript 5]Connected Cognition Diagram" as a lens to explore video data showing teachers' interactions related to the partitioning of regions by axes in a three-dimensional geometric space. The study considers "semiotic bundles" (Arzarello, 2006), introduces "semiotic connections,"…

  1. myFX: a turn-key software for laboratory desktops to analyze spatial patterns of gene expression in Drosophila embryos.

    Science.gov (United States)

    Montiel, Ivan; Konikoff, Charlotte; Braun, Bremen; Packard, Mary; Gramates, Sian L; Sun, Qian; Ye, Jieping; Kumar, Sudhir

    2014-05-01

    Spatial patterns of gene expression are of key importance in understanding developmental networks. Using in situ hybridization, many laboratories are generating images to describe these spatial patterns and to test biological hypotheses. To facilitate such analyses, we have developed biologist-centric software (myFX) that contains computational methods to automatically process and analyze images depicting embryonic gene expression in the fruit fly Drosophila melanogaster. It facilitates creating digital descriptions of spatial patterns in images and enables measurements of pattern similarity and visualization of expression across genes and developmental stages. myFX interacts directly with the online FlyExpress database, which allows users to search thousands of existing patterns to find co-expressed genes by image comparison.

  2. Extracting Usage Patterns and the Analysis of Tag Connection Dynamics within Collaborative Tagging Systems

    Directory of Open Access Journals (Sweden)

    Daniel MICAN

    2013-01-01

    Full Text Available Collaborative tagging has become a very popular way of annotation, thanks to the fact that any entity may be labeled by any individual based on his own reason. In this paper we present the results of the case study carried out on the basis of data gathered at different time intervals from the social tagging system developed and implemented on Întelepciune.ro. Analyzing collective data referring to the way in which community members associate different tags, we have observed that between tags, links are formed which become increasingly stable with the passing of time. Following the application of methodology specific to network analysis, we have managed to extract information referring to tag popularity, their influence within the network and the degree to which a tag depends upon another. As such, we have succeeded in determining different semantic structures within the collective tagging system and see their evolution at different stages in time. Furthermore, we have pictured the way in which tag rec-ommendations can be executed and that they can be integrated within recommendation sys-tems. Thus, we will be able to identify experts and trustworthy content based on different cat-egories of interest.

  3. A New Approach to Analyzing Patterns of Collaboration in Co-authorship Networks - Mesoscopic Analysis and Interpretation

    CERN Document Server

    Velden, Theresa A; Lagoze, Carl J

    2009-01-01

    This paper focuses on methods to study patterns of collaboration in co-authorship networks at the mesocopic level. We combine qualitative methods (participant interviews) with quantitative methods (network analysis) and demonstrate the value of our approach in a case study comparing three research fields in chemistry. A mesoscopic level of analysis means that in addition to the basic analytic unit of the individual researcher as node in a co-author network, we analyse the clustering of authors into groups that we interpret as basic collective units of knowledge production in a research specialty. We find a variety of structural types of these clusters that point to potential variations in the underlying social configurations and collaborative working modes of the collective units in the respective research specialties. We further identify two types of co-authorship relations between clusters of authors based on linkage patterns. One type corresponds to extensive inter-group collaboration and the other type to...

  4. Association between magnetic resonance imaging patterns and baseline disease features in multiple myeloma: analyzing surrogates of tumour mass and biology

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Elias K.; Merz, Maximilian; Shah, Sofia; Hillengass, Michaela; Wagner, Barbara; Hose, Dirk; Raab, M.S. [University Hospital Heidelberg, Department of Internal Medicine V, Heidelberg (Germany); Hielscher, Thomas [German Cancer Research Center, Division of Biostatistics, Heidelberg (Germany); Kloth, Jost K.; Weber, Marc-Andre [University Hospital of Heidelberg, Clinic of Diagnostic and Interventional Radiology, Heidelberg (Germany); Jauch, Anna [University Hospital of Heidelberg, Institute of Human Genetics, Heidelberg (Germany); Delorme, Stefan [German Cancer Research Center, Department of Radiology, Heidelberg (Germany); Goldschmidt, Hartmut [University Hospital Heidelberg, Department of Internal Medicine V, Heidelberg (Germany); National Center for Tumor Diseases (NCT) Heidelberg, Heidelberg (Germany); Hillengass, Jens [University Hospital Heidelberg, Department of Internal Medicine V, Heidelberg (Germany); German Cancer Research Center, Department of Radiology, Heidelberg (Germany)

    2016-11-15

    To assess associations between bone marrow infiltration patterns and localization in magnetic resonance imaging (MRI) and baseline clinical/prognostic parameters in multiple myeloma (MM). We compared baseline MM parameters, MRI patterns and localization of focal lesions to the mineralized bone in 206 newly diagnosed MM patients. A high tumour mass (represented by International Staging System stage III) was significantly associated with severe diffuse infiltration (p = 0.015) and a higher number of focal lesions (p = 0.006). Elevated creatinine (p = 0.003), anaemia (p < 0.001) and high LDH (p = 0.001) correlated with severe diffuse infiltration. A salt and pepper diffuse pattern had a favourable prognosis. A higher degree of destruction of mineralized bone (assessed by X-ray or computed tomography) was associated with an increasing number of focal lesions on MRI (p < 0.001). Adverse cytogenetics (del17p/gain1q21/t(4;14)) were associated with diffuse infiltration (p = 0.008). The presence of intraosseous focal lesions exceeding the mineralized bone had a borderline significant impact on prognosis. Diffuse bone marrow infiltration on MRI correlates with adverse cytogenetics, lowered haemoglobin values and high tumour burden in newly diagnosed MM whereas an increasing number of focal lesions correlates with a higher degree of bone destruction. Focal lesions exceeding the cortical bone did not adversely affect the prognosis. (orig.)

  5. Analyzing the relationship between peak runoff discharge and land-use pattern – a spatial optimization approach

    Directory of Open Access Journals (Sweden)

    I.-Y. Yeo

    2009-04-01

    Full Text Available This paper investigates the impacts of land-use patterns on watershed hydrology and characterizes the nature of this relationship. The approach combines a spatially explicit, process-based hydrological simulation model, a land-use optimization model, the Integrated Hydrological and Land-Use Optimization (IHLUO model, and an extensive GIS database. Numerical experiments are conducted to assess changes in the peak discharge rate under various spatial land-use arrangements, and to delineate the optimal land distribution that minimizes the peak discharge. The area of application is a catchment of the Old Woman Creek watershed in the southwestern coastal area of Lake Erie, OH. The global optimality of the delineated land pattern at a 30-m resolution is evaluated using a combinatorial statistical method. A large number of solutions has been generated from clearly different initial solutions, and these solutions turn out to be very close to each other, strongly supporting the case for a convex relationship between peak discharge and land-use pattern. The Weibull distribution is used to generate a point estimate of the global optimal value and its confidence interval. The peak discharge function is further examined in light of the underlying physics used in the simulation model.

  6. Conservation patterns of HIV-1 RT connection and RNase H domains: identification of new mutations in NRTI-treated patients.

    Directory of Open Access Journals (Sweden)

    André F A Santos

    Full Text Available BACKGROUND: Although extensive HIV drug resistance information is available for the first 400 amino acids of its reverse transcriptase, the impact of antiretroviral treatment in C-terminal domains of Pol (thumb, connection and RNase H is poorly understood. METHODS AND FINDINGS: We wanted to characterize conserved regions in RT C-terminal domains among HIV-1 group M subtypes and CRF. Additionally, we wished to identify NRTI-related mutations in HIV-1 RT C-terminal domains. We sequenced 118 RNase H domains from clinical viral isolates in Brazil, and analyzed 510 thumb and connection domain and 450 RNase H domain sequences collected from public HIV sequence databases, together with their treatment status and histories. Drug-naïve and NRTI-treated datasets were compared for intra- and inter-group conservation, and differences were determined using Fisher's exact tests. One third of RT C-terminal residues were found to be conserved among group M variants. Three mutations were found exclusively in NRTI-treated isolates. Nine mutations in the connection and 6 mutations in the RNase H were associated with NRTI treatment in subtype B. Some of them lay in or close to amino acid residues which contact nucleic acid or near the RNase H active site. Several of the residues pointed out herein have been recently associated to NRTI exposure or increase drug resistance to NRTI. CONCLUSIONS: This is the first comprehensive genotypic analysis of a large sequence dataset that describes NRTI-related mutations in HIV-1 RT C-terminal domains in vivo. The findings into the conservation of RT C-terminal domains may pave the way to more rational drug design initiatives targeting those regions.

  7. Storage of phase-coded patterns via STDP in fully-connected and sparse network: a study of the network capacity

    Directory of Open Access Journals (Sweden)

    Silvia Scarpetta

    2010-08-01

    Full Text Available We study the storage and retrieval of phase-coded patterns as stable dynamical attractors in recurrent neural networks, for both an analog and a integrate-and-fire spiking model. The synaptic strength is determined by a learning rule based on spike-time-dependent plasticity, with an asymmetric time window depending on the relative timing between pre- and post-synaptic activity. We store multiple patterns and study the network capacity. For the analog model, we find that the network capacity scales linearly with the network size, and that both capacity and the oscillation frequency of the retrieval state depend on the asymmetry of the learning time window. In addition to fully-connected networks, we study sparse networks, where each neuron is connected only to a small number $zll N$ of other neurons. Connections can be short range, between neighboring neurons placed on a regular lattice, or long range, between randomly chosen pairs of neurons. We find that a small fraction of long range connections is able to amplify the capacity of the network. This imply that a small-world-network topology is optimal, as a compromise between the cost of long range connections and the capacity increase. Also in the spiking integrate and fire model the crucial result of storing and retrieval of multiple phase-coded patterns is observed. The capacity of the fully-connected spiking network is investigated, together with the relation between oscillation frequency of retrieval state and window asymmetry.

  8. Connectivity patterns and key non–breeding areas of white–throated bluethroat (Luscinia svecica European populations

    Directory of Open Access Journals (Sweden)

    Arizaga, J.

    2013-01-01

    Full Text Available Using ring recovery data from the EURING databank, the aims of this study were: (1 to identify the chief migration and wintering areas of white–throated bluethroat European subspecies, L. s. namnetum, L. s. cyanecula and L. s. azuricollis, (2 to evaluate the degree of connectivity between breeding and non–breeding regions and determine the migration patterns of each subspecies, and (3 to evaluate whether recovery data are sufficient to answer the previous questions adequately. Most of the recoveries were obtained during the autumn migration period (n = 155, 68.9%, followed by winter (n = 49, 21.8% and spring (n = 21, 9.3%. For L. s. azuricollis, we did not find any ring recoveries at more than 100 km in autumn or spring, and there were none at all in winter. All analyses thus relate to L. s. cyanecula and L. s. namnetum. Both subspecies move across a NE–SW axis from their breeding to their wintering areas within the circum–Mediterranean region, mainly in Iberia, following population–specific parallel migration routes. L. s. namnetum mainly uses the Atlantic coastal marshes from France to south–western Iberia, where the chief wintering areas are found. L. s. cyanecula, however, uses both Atlantic and Mediterranean wetlands in autumn, but only those in the Mediterranean in spring, thus giving rise to a loop–migration pattern. Telescopic migration was demonstrated for L. s. cyanecula. Recovery data were insufficient to identify in detail the entire wintering range for all white–throated bluethroat European populations. Technologies such as the use of geolocators will play a relevant role in this scenario

  9. Using Genome-Referenced Expressed Sequence Tag Assembly to Analyze the Origin and Expression Patterns of Gossypium hirsutum Transcripts

    Institute of Scientific and Technical Information of China (English)

    Xiang Jin; Qin Li; Guanghui Xiao; Yu-Xian Zhu

    2013-01-01

    We assembled a total of 297,239 Gossypium hirsutum (Gh,a tetraploid cotton,AADD) expressed sequence tag (EST) sequences that were available in the National Center for Biotechnology Information database,with reference to the recently published G.raimondii (Gr,a diploid cotton,DD) genome,and obtained 49,125 UniGenes.The average lengths of the UniGenes were increased from 804 and 791 bp in two previous EST assemblies to 1,019 bp in the current analysis.The number of putative cotton UniGenes with lengths of 3 kb or more increased from 25 or 34 to 1,223.As a result,thousands of originally independent G.hirsutum ESTs were aligned to produce large contigs encoding transcripts with very long open reading frames,indicating that the G.raimondii genome sequence provided remarkable advantages to assemble the tetraploid cotton transcriptome.Significant different distribution patterns within several GO terms,including transcription factor activity,were observed between D-and A-derived assemblies.Transcriptome analysis showed that,in a tetraploid cotton cell,29,547 UniGenes were possibly derived from the D subgenome while another 19,578 may come from the A subgenome.Finally,some of the in silico data were confirmed by reverse transcription polymerase chain reaction experiments to show the changes in transcript levels for several gene families known to play key role in cotton fiber development.We believe that our work provides a useful platform for functional and evolutionary genomic studies in cotton.

  10. Utilizing mixed methods research in analyzing Iranian researchers’ informarion search behaviour in the Web and presenting current pattern

    Directory of Open Access Journals (Sweden)

    Maryam Asadi

    2015-12-01

    Full Text Available Using mixed methods research design, the current study has analyzed Iranian researchers’ information searching behaviour on the Web.Then based on extracted concepts, the model of their information searching behavior was revealed. . Forty-four participants, including academic staff from universities and research centers were recruited for this study selected by purposive sampling. Data were gathered from questionnairs including ten questions and semi-structured interview. Each participant’s memos were analyzed using grounded theory methods adapted from Strauss & Corbin (1998. Results showed that the main objectives of subjects were doing a research, writing a paper, studying, doing assignments, downloading files and acquiring public information in using Web. The most important of learning about how to search and retrieve information were trial and error and get help from friends among the subjects. Information resources are identified by searching in information resources (e.g. search engines, references in papers, and search in Online database… communications facilities & tools (e.g. contact with colleagues, seminars & workshops, social networking..., and information services (e.g. RSS, Alerting, and SDI. Also, Findings indicated that searching by search engines, reviewing references, searching in online databases, and contact with colleagues and studying last issue of the electronic journals were the most important for searching. The most important strategies were using search engines and scientific tools such as Google Scholar. In addition, utilizing from simple (Quick search method was the most common among subjects. Using of topic, keywords, title of paper were most important of elements for retrieval information. Analysis of interview showed that there were nine stages in researchers’ information searching behaviour: topic selection, initiating search, formulating search query, information retrieval, access to information

  11. Comprehending text versus reading words in young readers with varying reading ability: distinct patterns of functional connectivity from common processing hubs.

    Science.gov (United States)

    Aboud, Katherine S; Bailey, Stephen K; Petrill, Stephen A; Cutting, Laurie E

    2016-07-01

    Skilled reading depends on recognizing words efficiently in isolation (word-level processing; WL) and extracting meaning from text (discourse-level processing; DL); deficiencies in either result in poor reading. FMRI has revealed consistent overlapping networks in word and passage reading, as well as unique regions for DL processing; however, less is known about how WL and DL processes interact. Here we examined functional connectivity from seed regions derived from where BOLD signal overlapped during word and passage reading in 38 adolescents ranging in reading ability, hypothesizing that even though certain regions support word- and higher-level language, connectivity patterns from overlapping regions would be task modulated. Results indeed revealed that the left-lateralized semantic and working memory (WM) seed regions showed task-dependent functional connectivity patterns: during DL processes, semantic and WM nodes all correlated with the left angular gyrus, a region implicated in semantic memory/coherence building. In contrast, during WL, these nodes coordinated with a traditional WL area (left occipitotemporal region). In addition, these WL and DL findings were modulated by decoding and comprehension abilities, respectively, with poorer abilities correlating with decreased connectivity. Findings indicate that key regions may uniquely contribute to multiple levels of reading; we speculate that these connectivity patterns may be especially salient for reading outcomes and intervention response.

  12. Expression pattern of glycoconjugates in the Bidderian and ovarian follicles of the Brazilian toad Bufo ictericus analyzed by lectin histochemistry

    Directory of Open Access Journals (Sweden)

    C. F. Farias

    Full Text Available The Bidder's organ and ovary of the Brazilian toad Bufo ictericus were studied by light microscopy, using hematoxylin-eosin (HE and periodic acid Schiff (PAS staining. The expression and distribution of carbohydrate moieties was analyzed by lectin histochemistry, using 8 lectins with different carbohydrate specificities: Ulex europaeus (UEA I, Lens culinaris (LCA, Erythrina cristagalli (ECA, Arachis hypogaea (PNA, Ricinus communis (RCA I, Aleuria aurantia (AAA, Triticum vulgaris (WGA, and Glycine maximum (SBA. The results showed that the Bidderian zona pellucida presented alpha-mannose, alpha-L-fucose, beta-D-galactose, N-acetyl-D-glucosamine, and alpha/beta-N-acetyl-galactosamine residues. The Bidderian follicular cells showed the presence of beta-D-galactose and N-acetyl-D-glucosamine. In the extracellular matrix, alpha-mannose and alpha/beta-N-acetyl-galactosamine residues were detected. The ovarian zona pellucida showed alpha-L-fucose, N-acetyl-D-glucosamine, alpha/beta-N-acetyl-galactosamine residues, and alpha-mannose and N-acetyl-D-glucosamine residues were detected in the follicular cells. Thus, the zona pellucida in both organs contains N-acetyl-D-glucosamine, and alpha/beta-N-acetyl-galactosamine residues. alpha-L-fucose residues were detected in the zona pellucida of both organs, using different lectins. Considering that beta-D-galactose residue was absent from ovary but present in the Bidder's organ, this sugar residue may play an important role in follicle development, blocking the Bidderian follicles and preventing further development of the Bidder's organ into a functional ovary.

  13. [Analyzing moiré pattern spectra based on the mutual transform between signals' waveform in time domain and their spectra in frequency space].

    Science.gov (United States)

    Sun, Tao; Song, Yi-Zhong

    2013-11-01

    The mutual evolving processes of signals' waveforms and their spectra were numerically analyzed in time and frequency domains. The purpose was to research the essential relation between the signals' waveforms and their spectra. Then, the mutual transform principle was applied to analyze moiré pattern spectra, acquiring phase distribution information of the pattern. The rectangular window function was used to simulate the mutual transform between the impulse signal and direct-current waveform. Many rectangular window signals with deferent widths were obtained by changing the window width The unit impulse signal was obtained by changing the width down to zero, and the direct-current waveform obtained by changing the width up to +infinity. For smart, quick, and easy implementation of discrete Fourier transforms to rectangular pulses and obtain signals' spectra, a simple FFT system was worked out. With its calculating, the mutual evolving processes of signals' waveforms and their spectra were tracked deeply. All signals here were transformed with it. As the result, first, the spectra of rectangular window signals were in the form of sampling function [Sa(x) = sin(x)/x]. Second, with the change in the window's width, the waveform of Sa(x) changed. Third, when the width decreased, the waveform of Sa(x) extended, and vibrated more slowly. It changed into direct-current waveform when the width decreased to zero. Last, when the width increased, the waveform of Sa(x) shranked, and vibrated faster. It changed into impulse waveform when the width increased to +infinity. Signals' waveforms were in mutual transforms between the time and frequency domain. The transforming essence was considered as that the frequency component principle in Fourier series theory is reflected in the frequency domain. According to the principle of mutual transforms between signals' waveforms and their spectra, the first order spectrum of the moiré pattern was extracted out and normalized to a

  14. Optimization of anesthesia protocol for resting-state fMRI in mice based on differential effects of anesthetics on functional connectivity patterns.

    Science.gov (United States)

    Grandjean, Joanes; Schroeter, Aileen; Batata, Imene; Rudin, Markus

    2014-11-15

    Resting state-fMRI (rs-fMRI) in mice allows studying mechanisms underlying functional connectivity (FC) as well as alterations of FC occurring in murine models of neurological diseases. Mouse fMRI experiments are typically carried out under anesthesia to minimize animal movement and potential distress during examination. Yet, anesthesia inevitably affects FC patterns. Such effects have to be understood for proper interpretation of data. We have compared the influence of four commonly used anesthetics on rs-fMRI. Rs-fMRI data acquired under isoflurane, propofol, and urethane presented similar patterns when accounting for anesthesia depth. FC maps displayed bilateral correlation with respect to cortical seeds, but no significant inter-hemispheric striatal connectivity. In contrast, for medetomidine, we detected bilateral striatal but compromised inter-hemispheric cortical connectivity. The spatiotemporal patterns of the rs-fMRI signal have been rationalized considering anesthesia depth and pharmacodynamic properties of the anesthetics. Our results bridge the results from different studies from the burgeoning field of mouse rs-fMRI and offer a framework for understanding the influences of anesthetics on FC patterns. Utilizing this information, we suggest the combined use of medetomidine and isoflurane representing the two proposed classes of anesthetics; the combination of low doses of the two anesthetics retained strong correlations both within cortical and subcortical structures, without the potential seizure-inducing effects of medetomidine, rendering this regimen an attractive anesthesia for rs-fMRI in mice.

  15. 金融市场联动形态结构的非线性分析%Nonlinear analysis on the pattern structures of connection between financial markets

    Institute of Scientific and Technical Information of China (English)

    沈传河; 王向荣

    2015-01-01

    This paper analyzes the connection between the money market and the capital market in a micro level sense,investigates the connection approaches and their pattern structures,and mines deeply the dynam-ics of interactions between the two markets through the integration of support vector machines( SVM)into cop-ula functions. The modified sample-weighted SVM is employed to estimate the marginal probability distribution functions of the money market price,SHIBOR,and the stock price index return of the capital market in terms of the nonlinearity and instability of financial variable time series,and the optimized copula function is then used to analyze the joint probability distributions of the two financial variables and their change scenarios under various circumstances,with the dependence structures between the two markets and the dynamics of the non-linear connection obtained. The empirical analysis shows that the joint distribution probability of 1Y-SHIBOR and the stock price index return exhibit different structure characteristics under different directions and magni-tudes when changing the two variables above,there exists asymmetries,and the stress test analysis gives simi-lar results.%从微观层面分析货币市场与资本市场的联结问题,通过构建支持向量机( SVM)和Copu-la函数的集成系统,研究金融市场联结途径与形态结构,深层次挖掘两个市场互动的规律。针对金融时间序列的非线性、非平稳特性,利用改进的样本加权支持向量机估计SHIBOR和股票市场价格指数收益率的边缘概率分布函数。然后,再采用优选的Copula函数进一步分析它们的联合概率分布及其在不同情形下的变化情况,获得了货币市场与资本市场联动的相依结构与非线性联结的动态特性。实证分析表明,1 Y-SHIBOR和股票市场价格指数收益率的联合分布概率在两者不同变化方向和幅度上表现出不同的变化规律,并存在

  16. Altered patterns of directed connectivity within the reading network of dyslexic children and their relation to reading dysfluency

    Directory of Open Access Journals (Sweden)

    Gojko Žarić

    2017-02-01

    Full Text Available Reading is a complex cognitive skill subserved by a distributed network of visual and language-related regions. Disruptions of connectivity within this network have been associated with developmental dyslexia but their relation to individual differences in the severity of reading problems remains unclear. Here we investigate whether dysfunctional connectivity scales with the level of reading dysfluency by examining EEG recordings during visual word and false font processing in 9-year-old typically reading children (TR and two groups of dyslexic children: severely dysfluent (SDD and moderately dysfluent (MDD dyslexics. Results indicated weaker occipital to inferior-temporal connectivity for words in both dyslexic groups relative to TRs. Furthermore, SDDs exhibited stronger connectivity from left central to right inferior-temporal and occipital sites for words relative to TRs, and for false fonts relative to both MDDs and TRs. Importantly, reading fluency was positively related with forward and negatively with backward connectivity. Our results suggest disrupted visual processing of words in both dyslexic groups, together with a compensatory recruitment of right posterior brain regions especially in the SDDs during word and false font processing. Functional connectivity in the brain’s reading network may thus depend on the level of reading dysfluency beyond group differences between dyslexic and typical readers.

  17. Learning Connections

    Science.gov (United States)

    Royer, Regina D.; Richards, Patricia O.

    2005-01-01

    In this edition of Learning Connections, the authors show how technology can enhance study of weather patterns, reading comprehension, real-world training, critical thinking, health education, and art criticism. The following sections are included: (1) Social Studies; (2) Language Arts; (3) Computer Science and ICT; (4) Art; and (5) Health.…

  18. Analyzing the patterns of travel behavior of Jessore City Analisando a distribuição de viagens na cidade de Jessore

    Directory of Open Access Journals (Sweden)

    Khan Rubayet Rahaman

    2010-04-01

    Full Text Available The purpose of this paper is to examine what is known about travel behavior and analyzing the existing pattern of travel behavior of Jessore City. In Jessore City about 83% trips are home based. There are a large number of decisions that people make about their travel behavior, such as their destinations, the mode (car or bus, for example, the time of day they travel, organizing individual trips into chains, and so on. In addition, broader factors such as population, economic growth, and technological changes can impact travel decisions. In this study several spatial or geographical factors, like the local service accessibility, have been studied in order to explain the differences in travel patterns. It is found that once monthly household income increased, the number of home-based trips per household per day also increased.Among the different mode of travel available in Jessore City, rickshaw (tri cycle human hauler is the most popular and easily available mode of travel. The study also tries to define how local factors – so called spatial factors – affect the travel behavior. The basic hypothesis is that in Jessore City, where the local service level is low and distances to service areas are long, the number of daily trips is smaller.

  19. Temporal and spatial patterns of wetland extent influence variability of surface water connectivity in the Prairie Pothole Region, United States

    Science.gov (United States)

    Vanderhoof, Melanie; Alexander, Laurie C.; Todd, Jason

    2016-01-01

    Context. Quantifying variability in landscape-scale surface water connectivity can help improve our understanding of the multiple effects of wetlands on downstream waterways. Objectives. We examined how wetland merging and the coalescence of wetlands with streams varied both spatially (among ecoregions) and interannually (from drought to deluge) across parts of the Prairie Pothole Region. Methods. Wetland extent was derived over a time series (1990-2011) using Landsat imagery. Changes in landscape-scale connectivity, generated by the physical coalescence of wetlands with other surface water features, were quantified by fusing static wetland and stream datasets with Landsat-derived wetland extent maps, and related to multiple wetness indices. The usage of Landsat allows for decadal-scale analysis, but limits the types of surface water connections that can be detected. Results. Wetland extent correlated positively with the merging of wetlands and wetlands with streams. Wetness conditions, as defined by drought indices and runoff, were positively correlated with wetland extent, but less consistently correlated with measures of surface water connectivity. The degree of wetland-wetland merging was found to depend less on total wetland area or density, and more on climate conditions, as well as the threshold for how wetland/upland was defined. In contrast, the merging of wetlands with streams was positively correlated with stream density, and inversely related to wetland density. Conclusions. Characterizing the degree of surface water connectivity within the Prairie Pothole Region in North America requires consideration of 1) climate-driven variation in wetness conditions and 2) within-region variation in wetland and stream spatial arrangements.

  20. Effects of Chronic Sleep Restriction during Early Adolescence on the Adult Pattern of Connectivity of Mouse Secondary Motor Cortex123

    Science.gov (United States)

    Billeh, Yazan N.; Bernard, Amy; de Vivo, Luisa; Honjoh, Sakiko; Mihalas, Stefan; Ng, Lydia; Koch, Christof

    2016-01-01

    Abstract Cortical circuits mature in stages, from early synaptogenesis and synaptic pruning to late synaptic refinement, resulting in the adult anatomical connection matrix. Because the mature matrix is largely fixed, genetic or environmental factors interfering with its establishment can have irreversible effects. Sleep disruption is rarely considered among those factors, and previous studies have focused on very young animals and the acute effects of sleep deprivation on neuronal morphology and cortical plasticity. Adolescence is a sensitive time for brain remodeling, yet whether chronic sleep restriction (CSR) during adolescence has long-term effects on brain connectivity remains unclear. We used viral-mediated axonal labeling and serial two-photon tomography to measure brain-wide projections from secondary motor cortex (MOs), a high-order area with diffuse projections. For each MOs target, we calculated the projection fraction, a combined measure of passing fibers and axonal terminals normalized for the size of each target. We found no homogeneous differences in MOs projection fraction between mice subjected to 5 days of CSR during early adolescence (P25–P30, ≥50% decrease in daily sleep, n=14) and siblings that slept undisturbed (n=14). Machine learning algorithms, however, classified animals at significantly above chance levels, indicating that differences between the two groups exist, but are subtle and heterogeneous. Thus, sleep disruption in early adolescence may affect adult brain connectivity. However, because our method relies on a global measure of projection density and was not previously used to measure connectivity changes due to behavioral manipulations, definitive conclusions on the long-term structural effects of early CSR require additional experiments. PMID:27351022

  1. Local adaptation and oceanographic connectivity patterns explain genetic differentiation of a marine diatom across the North Sea-Baltic Sea salinity gradient.

    Science.gov (United States)

    Sjöqvist, C; Godhe, A; Jonsson, P R; Sundqvist, L; Kremp, A

    2015-06-01

    Drivers of population genetic structure are still poorly understood in marine micro-organisms. We exploited the North Sea-Baltic Sea transition for investigating the seascape genetics of a marine diatom, Skeletonema marinoi. Eight polymorphic microsatellite loci were analysed in 354 individuals from ten locations to analyse population structure of the species along a 1500-km-long salinity gradient ranging from 3 to 30 psu. To test for salinity adaptation, salinity reaction norms were determined for sets of strains originating from three different salinity regimes of the gradient. Modelled oceanographic connectivity was compared to directional relative migration by correlation analyses to examine oceanographic drivers. Population genetic analyses showed distinct genetic divergence of a low-salinity Baltic Sea population and a high-salinity North Sea population, coinciding with the most evident physical dispersal barrier in the area, the Danish Straits. Baltic Sea populations displayed reduced genetic diversity compared to North Sea populations. Growth optima of low salinity isolates were significantly lower than those of strains from higher native salinities, indicating local salinity adaptation. Although the North Sea-Baltic Sea transition was identified as a barrier to gene flow, migration between Baltic Sea and North Sea populations occurred. However, the presence of differentiated neutral markers on each side of the transition zone suggests that migrants are maladapted. It is concluded that local salinity adaptation, supported by oceanographic connectivity patterns creating an asymmetric migration pattern between the Baltic Sea and the North Sea, determines genetic differentiation patterns in the transition zone.

  2. Goal directed worry rules are associated with distinct patterns of amygdala functional connectivity and vagal modulation during perseverative cognition

    Directory of Open Access Journals (Sweden)

    Frances Meeten

    2016-11-01

    Full Text Available Excessive and uncontrollable worry is a defining feature of Generalized Anxiety Disorder. An important endeavor in the treatment of pathological worry is to understand why some people are unable to stop worrying once they have started. Worry perseveration is associated with a tendency to deploy goal-directed worry rules (known as ‘as many as can’ worry rules; AMA. These require attention to the goal of the worry task and continuation of worry until the aims of the ‘worry bout’ are achieved. This study examined the association between the tendency to use AMA worry rules and neural and autonomic responses to a perseverative cognition induction. To differentiate processes underlying AMA worry rule use from trait worry, we also examined the relationship between scores on the Penn State Worry Questionnaire and neural and autonomic responses following the same induction. We used resting-state functional magnetic resonance brain imaging while measuring emotional bodily arousal from heart rate variability (where decreased HRV indicates stress-related parasympathetic withdrawal in 19 patients with GAD and 21 control participants. Seed-based analyses were conducted to quantify brain changes in functional connectivity with the amygdala. The tendency to adopt an AMA worry rule was associated with validated measures of worry, anxiety, depression, and rumination. AMA worry rule endorsement predicted a stronger decrease in HRV and was positively associated with increased connectivity between right amygdala and locus coeruleus, a brainstem noradrenergic projection nucleus. Higher AMA scores were also associated with increased connectivity between amygdala and rostral superior frontal gyrus. Higher PSWQ scores amplified decreases in functional connectivity between right amygdala and subcallosal cortex, bilateral inferior frontal gyrus, middle frontal gyrus, and areas of parietal cortex. Our results identify neural mechanisms underlying the deployment of

  3. Distribution pattern of left-ventricular myocardial strain analyzed by a cine MRI based deformation registration algorithm in healthy Chinese volunteers

    Science.gov (United States)

    Liu, Hong; Yang, Dan; Wan, Ke; Luo, Yong; Sun, Jia-Yu; Zhang, Tian-Jing; Li, Wei-Hao; Greiser, Andreas; Jolly, Marie-Pierre; Zhang, Qing; Chen, Yu-Cheng

    2017-01-01

    The cine magnetic resonance imaging based technique feature tracking-cardiac magnetic resonance (FT-CMR) is emerging as a novel, simple and robust method to evaluate myocardial strain. We investigated the distribution characteristics of left-ventricular myocardial strain using a novel cine MRI based deformation registration algorithm (DRA) in a cohort of healthy Chinese subjects. A total of 130 healthy Chinese subjects were enrolled. Three components of orthogonal strain (radial, circumferential, longitudinal) of the left ventricle were analyzed using DRA on steady-state free precession cine sequence images. A distinct transmural circumferential strain gradient was observed in the left ventricle that showed universal increment from the epicardial to endocardial myocardial wall (epiwall: −15.4 ± 1.9%; midwall: −18.8 ± 2.0%; endowall: −22.3 ± 2.3%, P < 0.001). Longitudinal strain showed a similar trend from epicardial to endocardial layers (epiwall: −16.0 ± 2.9%; midwall: −15.6 ± 2.7%; endowall: −14.8 ± 2.4%, P < 0.001), but radial strain had a very heterogeneous distribution and variation. In the longitudinal direction from the base to the apex of the left ventricle, there was a trend of decreasing peak systolic longitudinal strain (basal: −23.3 ± 4.6%; mid: −13.7 ± 7.3%; apical: −13.2 ± 5.5%; P < 0.001). In conclusion, there are distinct distribution patterns of circumferential and longitudinal strain within the left ventricle in healthy Chinese subjects. These distribution patterns of strain may provide unique profiles for further study in different types of myocardial disease. PMID:28349989

  4. Connecting Self-Esteem and Achievement: Diversity in Academic Identification and Dis-Identification Patterns among Black College Students

    Science.gov (United States)

    Hope, Elan C.; Chavous, Tabbye M.; Jagers, Robert J.; Sellers, Robert M.

    2013-01-01

    Using a person-oriented approach, we explored patterns of self-esteem and achievement among 324 Black college students across the freshman college year and identified four academic identification profiles. Multivariate analyses revealed profile differences in academic and psychological outcomes at beginning and end of freshman year (academic…

  5. Formation of Self-Connected Si0.8Ge0.2 Lateral Nanowires and Pyramids on Rib-Patterned Si(1 1 10) Substrate.

    Science.gov (United States)

    Du, Lei; Chen, Gang; Lu, Wei

    2017-12-01

    In this work, Si0.8Ge0.2 is deposited onto the rib-patterned Si (1 1 10) template oriented in the [1 -1 0] direction. Atomic force microscopy (AFM) reveals that the rib sidewalls reshape into pyramid-covered (0 0 1) and smooth {1 1 3} facets, respectively, while the {1 0 5} facets-bounded lateral SiGe nanowires dominate the rib top along the [5 5 -1] direction. At both the rib shoulder sites and the pyramid vacancy sites, self-connecting occurs between the meeting nanowire and pyramids to form elongated huts, which are driven by the minimization of the total energy density according to the finite-element simulations results. These results suggest a convenient solution to form lateral SiGe nanowires covering multi-faceted surfaces on the patterned template.

  6. Activation and connectivity patterns of the presupplementary and dorsal premotor areas during free improvisation of melodies and rhythms.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-10-15

    Free, i.e. non-externally cued generation of movement sequences is fundamental to human behavior. We have earlier hypothesized that the dorsal premotor cortex (PMD), which has been consistently implicated in cognitive aspects of planning and selection of spatial motor sequences may be particularly important for the free generation of spatial movement sequences, whereas the pre-supplementary motor area (pre-SMA), which shows increased activation during perception, learning and reproduction of temporal sequences, may contribute more to the generation of temporal structures. Here we test this hypothesis using fMRI and musical improvisation in professional pianists as a model behavior. We employed a 2 × 2 factorial design with the factors Melody (Specified/Improvised) and Rhythm (Specified/Improvised). The main effect analyses partly confirmed our hypothesis: there was a main effect of Melody in the PMD; the pre-SMA was present in the main effect of Rhythm, as predicted, as well as in the main effect of Melody. A psychophysiological interaction analysis of functional connectivity demonstrated that the correlation in activity between the pre-SMA and cerebellum was higher during rhythmic improvisation than during the other conditions. In summary, there were only subtle differences in activity level between the pre-SMA and PMD during improvisation, regardless of condition. Consequently, the free generation of rhythmic and melodic structures, appears to be largely integrated processes but the functional connectivity between premotor areas and other regions may change during free generation in response to sequence-specific spatiotemporal demands.

  7. A bioinformatics prediction approach towards analyzing the glycosylation, co-expression and interaction patterns of epithelial membrane antigen (EMA/MUC1)

    Energy Technology Data Exchange (ETDEWEB)

    Kalra, Rajkumar S., E-mail: renu-wadhwa@aist.go.jp; Wadhwa, Renu, E-mail: renu-wadhwa@aist.go.jp [Cell Proliferation Research Group and DBT-AIST International Laboratory for Advanced Biomedicine, National Institute of Advanced Industrial Science and Technology (AIST Central 4), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8562 (Japan)

    2015-02-27

    Epithelial membrane antigen (EMA or MUC1) is a heavily glycosylated, type I transmembrane glycoprotein commonly expressed by epithelial cells of duct organs. It has been shown to be aberrantly glycosylated in several diseases including cancer. Protein sequence based annotation and analysis of glycosylation profile of glycoproteins by robust computational and comprehensive algorithms provides possible insights to the mechanism(s) of anomalous glycosylation. In present report, by using a number of bioinformatics applications we studied EMA/MUC1 and explored its trans-membrane structural domain sequence that is widely subjected to glycosylation. Exploration of different extracellular motifs led to prediction of N and O-linked glycosylation target sites. Based on the putative O-linked target sites, glycosylated moieties and pathways were envisaged. Furthermore, Protein network analysis demonstrated physical interaction of EMA with a number of proteins and confirmed its functional involvement in cell growth and proliferation pathways. Gene Ontology analysis suggested an involvement of EMA in a number of functions including signal transduction, protein binding, processing and transport along with glycosylation. Thus, present study explored potential of bioinformatics prediction approach in analyzing glycosylation, co-expression and interaction patterns of EMA/MUC1 glycoprotein.

  8. A bioinformatics prediction approach towards analyzing the glycosylation, co-expression and interaction patterns of epithelial membrane antigen (EMA/MUC1)

    Science.gov (United States)

    Kalra, Rajkumar S.; Wadhwa, Renu

    2015-02-01

    Epithelial membrane antigen (EMA or MUC1) is a heavily glycosylated, type I transmembrane glycoprotein commonly expressed by epithelial cells of duct organs. It has been shown to be aberrantly glycosylated in several diseases including cancer. Protein sequence based annotation and analysis of glycosylation profile of glycoproteins by robust computational and comprehensive algorithms provides possible insights to the mechanism(s) of anomalous glycosylation. In present report, by using a number of bioinformatics applications we studied EMA/MUC1 and explored its trans-membrane structural domain sequence that is widely subjected to glycosylation. Exploration of different extracellular motifs led to prediction of N and O-linked glycosylation target sites. Based on the putative O-linked target sites, glycosylated moieties and pathways were envisaged. Furthermore, Protein network analysis demonstrated physical interaction of EMA with a number of proteins and confirmed its functional involvement in cell growth and proliferation pathways. Gene Ontology analysis suggested an involvement of EMA in a number of functions including signal transduction, protein binding, processing & transport along with glycosylation. Thus, present study explored potential of bioinformatics prediction approach in analyzing glycosylation, co-expression and interaction patterns of EMA/MUC1 glycoprotein.

  9. Emergence of spatial behavioral function and associated mossy fiber connectivity and c-Fos labeling patterns in the hippocampus of rats.

    Science.gov (United States)

    Comba, Rachel; Gervais, Nicole; Mumby, Dave; Holahan, Matthew

    2015-01-01

    Improvement on spatial tasks is observed during a late, postnatal developmental period (PND18 - PND24).  The purpose of the current work was 1) to determine whether the emergence of spatial-behavioral function was based on the ability to generate appropriate behavioral output; 2) to assess whether mossy fiber connectivity patterns preceded the emergence of spatial-behavioral function; 3) to explore functional changes in the hippocampus to determine whether activity in hippocampal networks occurred in a training-dependent or developmentally-dependent fashion.  To these ends, male, Long Evans rats were trained on a spatial water or dry maze task for one day (PND16, PND18 or PND20) then euthanized.  Training on these 2 tasks with opposing behavioral demands (swimming versus exploration) was hypothesized to control for behavioral topology.  Only at PND20 was there evidence of spatial-behavioral function for both tasks.  Examination of synaptophysin staining in the CA3 region (i.e., mossy fiber projections) revealed enhanced connectivity patterns that preceded the emergence of spatial behavior.  Analysis of c-Fos labeling (functional changes) revealed developmentally-dependent increases in c-Fos positive cells in the dentate gyrus, CA3 and CA1 regions whereas training-dependent increases were noted in the CA3 and CA1 regions for the water-maze trained groups.  Results suggest that changes in mossy fiber connectivity in association with enhanced hippocampal functioning precede the emergence of spatial behavior observed at PND20.  The combination of neuroanatomical and behavioural results confirms the hypothesis that this time represents a sensitive period for hippocampal development and modification and the emergence of spatial/ cognitive function.

  10. Heart cycle-related effects on event-related potentials, spectral power changes, and connectivity patterns in the human ECoG.

    Science.gov (United States)

    Kern, Markus; Aertsen, Ad; Schulze-Bonhage, Andreas; Ball, Tonio

    2013-11-01

    The perception of one's own heartbeat is a fundamental interoceptive process that involves cortical and subcortical structures. Yet, the precise spatiotemporal neuronal activity patterns underlying the cortical information processing have remained largely elusive. Although the high temporal and spatial resolution of electrocorticographic (ECoG) recordings is increasingly being exploited in functional neuroimaging, it has not been used to study heart cycle-related effects. Here, we addressed the capacity of ECoG to characterize neuronal signals within the cardiac cycle, as well as to disentangle them from heart cycle-related artifacts. Based on topographical distribution and latency, we identified a biphasic potential within the primary somatosensory cortex, which likely constitutes a heartbeat-evoked potential (HEP) of neuronal origin. We also found two different types of artifacts: i) oscillatory potential changes with a frequency identical to the heart pulse rate, which probably represent pulsatility artifacts and ii) sharp potentials synchronized to the R-peak, corresponding to the onset of ventricular contraction and the cardiac field artifact (CFA) in EEG. Finally, we show that heart cycle-related effects induce pronounced phase-synchrony patterns in the ECoG and that this kind of correlation patterns, which may confound ECoG connectivity studies, can be reduced by a suitable correction algorithm. The present study is, to our knowledge, the first one to show a focally localized cortical HEP that could be clearly and consistently observed over subjects, suggesting a basic role of primary sensory cortex in processing of heart-related sensory inputs. We also conclude that taking into account and reducing heart cycle-related effects may be advantageous for many ECoG studies, and are of crucial importance, particularly for ECoG-based connectivity studies. Thus, in summary, although ECoG poses new challenges, it opens up new possibilities for the investigation of

  11. Sedimentation patterns across a Coastal Plain floodplain: The importance of hydrogeomorphic influences and cross-floodplain connectivity

    Science.gov (United States)

    Kaase, Christopher T.; Kupfer, John A.

    2016-09-01

    The floodplains of large Coastal Plain rivers in the southeastern U.S. are important long-term storage sites for alluvial sediment and nutrients. Yet considerable uncertainty surrounds sediment dynamics on many large river floodplains and, in particular, the local scale factors that affect the flux of sediment and nutrients from rivers onto their floodplains and their subsequent deposition. This research quantifies short-term rates of sediment deposition from 2012 to 2014 on floodplain sites at Congaree National Park using feldspar pads. Sediment deposition rates ranged from 0.1 to 15.6 cm (median = 1.46 cm) and were closely associated with inundation frequency and geomorphic position. Cross-floodplain distributary channels served as particularly important conduits for moving sediment onto the floodplain. Physical and chemical analyses of soil samples demonstrated that the most flood-exposed sites had higher major nutrient and micronutrient levels (especially of phosphorus) and more diverse nutrient compositions. This research advances current understandings of lateral floodplain connectivity by demonstrating the complex effects of regional hydrology and local floodplain environmental characteristics on the supply of sediment and nutrients.

  12. I-States-as-Objects-Analysis (ISOA): Extensions of an Approach to Studying Short-Term Developmental Processes by Analyzing Typical Patterns

    Science.gov (United States)

    Bergman, Lars R.; Nurmi, Jari-Erik; von Eye, Alexander A.

    2012-01-01

    I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the "i-state," defined as a person's pattern of variable…

  13. Tropical Cyclone Track Convergence Patterns, Arctic Sea-Ice Loss, and Superstorm Sandy: Is There a Connection?

    Science.gov (United States)

    Barnes, C. C.; Francis, J. A.; Byrne, J. M.; Graham, J. R.; McDaniel, S. A.

    2013-12-01

    The potential for disruption to populations and food production due to global climate change will be catastrophic in some regions. Among the most vulnerable regions are those impacted by intensifying or changing tropical cyclones (TC). The objective of this research is to identify historical trends in TC tracks and regional circulation patterns that may forecast increasing risks due to TC intensification under global climate warming. We carry out spatial and temporal analysis of the 1979 - 2011 International Best Track Archive for Climate Stewardship (IBTrACS) historical hurricane database. The data were divided into several subsets to allow analysis of trend in: (i) early (JJAS) and late (OND) seasonal trends; and (ii) multi-year intervals (1979-95 and 1996-2011) to differentiate possible long term trends, if any. Geographical Information Systems (GIS) overlay analysis of the IBTrACS 64 knot hurricane wind radii data identified varying levels of historical tropical cyclone track convergence in the North Atlantic (NA) basin. Results of the track convergence analysis provide a first order analysis regarding changing potential population vulnerabilities due to changing seasonal or long-term tropical cyclone activity. During the summer of 2012, the amount of sea ice on the Arctic Ocean was diminished to about half of its normal extent and 25% of its normal volume relative to the nearly steady conditions that existed before the 1980s. This record loss continues an inexorable decline observed during recent decades. The dramatic increase in open water allows much more solar energy absorption at high latitude. Most of this extra heat returns to the atmosphere in autumn, contributing to the Arctic's rate of warming; exceeding that of mid-latitudes by a factor of two to three, a phenomenon called Arctic Amplification (AA). During October 2012, prior to the arrival of Superstorm Sandy along the eastern seaboard, AA was particularly strong, resulting in a substantial

  14. Migratory connectivity of the monarch butterfly (Danaus plexippus: patterns of spring re-colonization in eastern North America.

    Directory of Open Access Journals (Sweden)

    Nathan G Miller

    Full Text Available Each year, millions of monarch butterflies (Danaus plexippus migrate up to 3000 km from their overwintering grounds in central Mexico to breed in eastern North America. Malcolm et al. (1993 articulated two non-mutually exclusive hypotheses to explain how Monarchs re-colonize North America each spring. The 'successive brood' hypothesis proposes that monarchs migrate from Mexico to the Gulf Coast, lay eggs and die, leaving northern re-colonization of the breeding range to subsequent generations. The 'single sweep' hypothesis proposes that overwintering monarchs continue to migrate northward after arriving on the Gulf coast and may reach the northern portion of the breeding range, laying eggs along the way. To examine these hypotheses, we sampled monarchs throughout the northern breeding range and combined stable-hydrogen isotopes (δD to estimate natal origin with wing wear scores to differentiate between individuals born in the current vs. previous year. Similar to Malcolm et al. (1993, we found that the majority of the northern breeding range was re-colonized by the first generation of monarchs (90%. We also estimated that a small number of individuals (10% originated directly from Mexico and, therefore adopted a sweep strategy. Contrary to Malcolm et al. (1993, we found that 62% of monarchs sampled in the Great Lakes originated from the Central U.S., suggesting that this region is important for sustaining production in the northern breeding areas. Our results provide new evidence of re-colonization patterns in monarchs and contribute important information towards identifying productive breeding regions of this unique migratory insect.

  15. Connectivity analysis of one-dimensional ad-hoc networks

    DEFF Research Database (Denmark)

    Bøgsted, Martin; Rasmussen, Jakob Gulddahl; Schwefel, Hans-Peter

    2011-01-01

    Application and communication protocols in dynamic ad-hoc networks are exposed to physical limitations imposed by the connectivity relations that result from mobility. Motivated by vehicular freeway scenarios, this paper analyzes a number of important connectivity metrics for instantaneous...... snapshots of stochastic geographic movement patterns: (1) The single-hop connectivity number, corresponding to the number of single-hop neighbors of a mobile node; (2) the multi-hop connectivity number, expressing the number of nodes reachable via multi-hop paths of arbitrary hop-count; (3) the connectivity...

  16. Scleroderma pattern of nailfold capillary changes as predictive value for the development of a connective tissue disease: a follow-up study of 3,029 patients with primary Raynaud's phenomenon.

    Science.gov (United States)

    Pavlov-Dolijanovic, Slavica; Damjanov, Nemanja S; Stojanovic, Roksanda M; Vujasinovic Stupar, Nada Z; Stanisavljevic, Dejana M

    2012-10-01

    To assess the prognostic value of scleroderma pattern of nailfold capillary changes for the development of connective tissue diseases (CTD) in subjects with primary Raynaud's phenomenon (RP). The study included 3,029 consecutive patients with primary RP who had been followed at 6-month intervals during the mean of 4.8 years. The pathological features of nailfold capillaroscopy were recorded in all patients who had neither clinical nor serological signs of a CTD. In patients who developed CTD, capillary changes obtained 6 months prior to diagnosis were analyzed. A possible relationship between capillary changes and the presence of associated CTD was assessed. At the end of follow-up, 1,660 (54,8%) patients have still the primary RP, 246 (8,1%) had suspected secondary RP, and 1,123 (37,1%) patients developed CTD (363 undifferentiated CTD, 263 systemic sclerosis, 143 systemic lupus erythematosus, 106 rheumatoid arthritis, 102 Sjögren's syndrome, 61 overlap syndrome, 30 vasculitides, 24 mixed CTD, 19 polymyositis, 7 dermatomyositis, and 5 primary antiphospholipid syndrome). Scleroderma pattern were significantly associated with the development of systemic sclerosis [P = .00001, sensitivity 94%, specificity 92%, positive predictive value 52%, negative predictive value 99%, and odds ratio 163 (95% CI, 97,9-271,5)], as well as dermatomyositis (P = .0004), overlap syndrome with signs of systemic sclerosis (P = .0001), and mixed connective tissue disease (P = .007). Capillary microscopy is effective method for differentiation between primary and secondary RP and useful tool for the prediction of scleroderma spectrum disorders in RP patients.

  17. Contrasting patterns of population connectivity between regions in a commercially important mollusc Haliotis rubra: integrating population genetics, genomics and marine LiDAR data.

    Science.gov (United States)

    Miller, A D; van Rooyen, A; Rašić, G; Ierodiaconou, D A; Gorfine, H K; Day, R; Wong, C; Hoffmann, A A; Weeks, A R

    2016-08-01

    Estimating contemporary genetic structure and population connectivity in marine species is challenging, often compromised by genetic markers that lack adequate sensitivity, and unstructured sampling regimes. We show how these limitations can be overcome via the integration of modern genotyping methods and sampling designs guided by LiDAR and SONAR data sets. Here we explore patterns of gene flow and local genetic structure in a commercially harvested abalone species (Haliotis rubra) from southeastern Australia, where the viability of fishing stocks is believed to be dictated by recruitment from local sources. Using a panel of microsatellite and genomewide SNP markers, we compare allele frequencies across a replicated hierarchical sampling area guided by bathymetric LiDAR imagery. Results indicate high levels of gene flow and no significant genetic structure within or between benthic reef habitats across 1400 km of coastline. These findings differ to those reported for other regions of the fishery indicating that larval supply is likely to be spatially variable, with implications for management and long-term recovery from stock depletion. The study highlights the utility of suitably designed genetic markers and spatially informed sampling strategies for gaining insights into recruitment patterns in benthic marine species, assisting in conservation planning and sustainable management of fisheries.

  18. InSilico DB genomic datasets hub: an efficient starting point for analyzing genome-wide studies in GenePattern, Integrative Genomics Viewer, and R/Bioconductor.

    Science.gov (United States)

    Coletta, Alain; Molter, Colin; Duqué, Robin; Steenhoff, David; Taminau, Jonatan; de Schaetzen, Virginie; Meganck, Stijn; Lazar, Cosmin; Venet, David; Detours, Vincent; Nowé, Ann; Bersini, Hugues; Weiss Solís, David Y

    2012-11-18

    Genomics datasets are increasingly useful for gaining biomedical insights, with adoption in the clinic underway. However, multiple hurdles related to data management stand in the way of their efficient large-scale utilization. The solution proposed is a web-based data storage hub. Having clear focus, flexibility and adaptability, InSilico DB seamlessly connects genomics dataset repositories to state-of-the-art and free GUI and command-line data analysis tools. The InSilico DB platform is a powerful collaborative environment, with advanced capabilities for biocuration, dataset sharing, and dataset subsetting and combination. InSilico DB is available from https://insilicodb.org.

  19. Utilizing TRMM to Analyze Sea Breeze Thunderstorm Patterns During El Nino Southern Oscillations and Their Effects upon Available Fresh Water for South Florida Agricultural Planning and Management

    Science.gov (United States)

    Cooley, Clayton; Billiot, Amanda; Lee, Lucas; McKee, Jake

    2010-01-01

    Water is in high demand for farmers regardless of where you go. Unfortunately, farmers in southern Florida have fewer options for water supplies than public users and are often limited to using available supplies from surface and ground water sources which depend in part upon variable weather patterns. There is an interest by the agricultural community about the effect weather has on usable surface water, however, research into viable weather patterns during La Nina and El Nino has yet to be researched. Using rainfall accumulation data from NASA Tropical Rainfall Measurement Mission (TRMM) satellite, this project s purpose was to assess the influence of El Nino and La Nina Oscillations on sea breeze thunderstorm patterns, as well as general rainfall patterns during the summer season in South Florida. Through this research we were able to illustrate the spatial and temporal variations in rainfall accumulation for each oscillation in relation to major agricultural areas. The study period for this project is from 1998, when TRMM was first launched, to 2009. Since sea breezes in Florida typically occur in the months of May through October, these months were chosen to be the months of the study. During this time, there were five periods of El Nino and two periods of La Nina, with a neutral period separating each oscillation. In order to eliminate rainfall from systems other than sea breeze thunderstorms, only days that were conducive to the development of a sea breeze front were selected.

  20. Breathing patterns of awake rats exposed to acrolein and perfluorisobutylene determined with an integrated system of nose-only exposure and online analyzed multiple monitoring of breathing

    NARCIS (Netherlands)

    Bergers, W.W.A.; Beyersbergen Van Henegouwen, A.G.; Hammer, A.H.; Bruijnzeel, P.L.B.

    1996-01-01

    Studies on changes in breathing patterns of rats due to exposure to acrolein and the Leflon pyrolysis product perfluorisobutylene (PFIB) were performed to evaluate a new developed integrated system of nose- only exposure and multiple monitoring of breathing of up to eight rats. Measurements of breat

  1. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae), within Malta's Fisheries Management Zone.

    Science.gov (United States)

    Buchholz-Sørensen, Molly; Vella, Adriana

    2016-01-01

    The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta's Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus' revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus' within the Fisheries Management Zone as decreasing in size (ƟH = 2.2), which has gone through a significant size reduction in the past (M = 0.41) and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001) with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta's Fisheries Management Zone and that they are connected to a larger network of E. marginatus' within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus' within Malta's Fisheries Management Zone

  2. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae, within Malta's Fisheries Management Zone.

    Directory of Open Access Journals (Sweden)

    Molly Buchholz-Sørensen

    Full Text Available The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta's Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus' revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus' within the Fisheries Management Zone as decreasing in size (ƟH = 2.2, which has gone through a significant size reduction in the past (M = 0.41 and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001 with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta's Fisheries Management Zone and that they are connected to a larger network of E. marginatus' within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus' within Malta's Fisheries

  3. Connectivity patterns during music listening

    DEFF Research Database (Denmark)

    Alluri, Vinoo; Toiviainen, Petri; Burunat, Iballa

    2017-01-01

    ' primary hubs comprised cerebral and cerebellar sensorimotor regions whereas non-musicians' dominant hubs encompassed DMN-related regions. Community structure analyses of the key hubs revealed greater integration of motor and somatosensory homunculi representing the upper limbs and torso in musicians....... Furthermore, musicians who started training at an earlier age exhibited greater centrality in the auditory cortex, and areas related to top-down processes, attention, emotion, somatosensory processing, and non-verbal processing of speech. We here reveal how brain networks organize themselves in a naturalistic......Musical expertise is visible both in the morphology and functionality of the brain. Recent research indicates that functional integration between multi-sensory, somato-motor, default-mode (DMN), and salience (SN) networks of the brain differentiates musicians from non-musicians during resting state...

  4. Analyzing Orientations

    Science.gov (United States)

    Ruggles, Clive L. N.

    Archaeoastronomical field survey typically involves the measurement of structural orientations (i.e., orientations along and between built structures) in relation to the visible landscape and particularly the surrounding horizon. This chapter focuses on the process of analyzing the astronomical potential of oriented structures, whether in the field or as a desktop appraisal, with the aim of establishing the archaeoastronomical "facts". It does not address questions of data selection (see instead Chap. 25, "Best Practice for Evaluating the Astronomical Significance of Archaeological Sites", 10.1007/978-1-4614-6141-8_25) or interpretation (see Chap. 24, "Nature and Analysis of Material Evidence Relevant to Archaeoastronomy", 10.1007/978-1-4614-6141-8_22). The main necessity is to determine the azimuth, horizon altitude, and declination in the direction "indicated" by any structural orientation. Normally, there are a range of possibilities, reflecting the various errors and uncertainties in estimating the intended (or, at least, the constructed) orientation, and in more formal approaches an attempt is made to assign a probability distribution extending over a spread of declinations. These probability distributions can then be cumulated in order to visualize and analyze the combined data from several orientations, so as to identify any consistent astronomical associations that can then be correlated with the declinations of particular astronomical objects or phenomena at any era in the past. The whole process raises various procedural and methodological issues and does not proceed in isolation from the consideration of corroborative data, which is essential in order to develop viable cultural interpretations.

  5. Long-term total sleep deprivation decreases the default spontaneous activity and connectivity pattern in healthy male subjects: a resting-state fMRI study

    Directory of Open Access Journals (Sweden)

    Dai XJ

    2015-03-01

    .33; P=0.021. The ICA method showed that, compared with RW subjects, SD subjects had decreased rsFC in the right inferior parietal lobule (IPL, BA40 and in the left precuneus (PrC/posterior cingulate cortex (PCC (BA30, 31. The two different areas were selected as regions of interest (ROIs for future rsFC analysis. Compared with the same in RW subjects, in SD subjects, the right IPL showed decreased rsFC with the left PrC (BA7 and increased rsFC with the left fusiform gyrus (BA37 and the left cluster of middle temporal gyrus and inferior temporal gyrus (BA37. However, the left PrC/PCC did not show any connectivity differences. Compared with RW subjects, SD subjects showed lower ALFF area in the left IPL (BA39, 40. The left IPL, as an ROI, showed decreased rsFC with the right cluster of IPL and superior temporal gyrus (BA39, 40. ROC curve analysis showed that the area under the curve (AUC value of the left IPL was 0.75, with a cutoff point of 0.834 (mean ALFF signal value. Further diagnostic analysis exhibited that the AUC alone discriminated SD status from RW status, with 75% sensitivity and 91.7% specificity. Conclusion: Long-term SD disturbed the spontaneous activity and connectivity pattern of DMN. Keywords: sleep deprivation, amplitude of low-frequency fluctuation, default-mode network, functional magnetic resonance imaging, functional connectivity, independent component analysis, receiver operating characteristic curve

  6. Analyzing opportunities for energy conservation in municipal fleet management: service delivery patterns, equipment, supply, operations, and maintenance. Information bulletin of the energy task force of the urban consortium

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    Vehicle fleet management as a five-step process is portrayed and the multiple energy conservation opportunities within each step are examined. The five steps described are, configuration of service area and service delivery patterns, equipping the fleet, operating the fleet, maintaining the fleet, and supplying the fleet with fuel. A systems approach to decision making about municipal fleets is outlined. Management options, control techniques, and devices are suggested for each of the five steps. Reference is made to analytic tools which will assist in deliberating options at each of these steps. These tools are presented in a list. Four concise case studies of jurisdictions which are taking deliberate steps to reduce fuel use are presented. Key opportunities for fuel conservation are then summarized, followed by a selected bibliography, and listing of reference materials and additional resources.

  7. Analyzing the Effects of Family Communication Patterns on the Decision to Disclose a Health Issue to a Parent: The Benefits of Conversation and Dangers of Conformity.

    Science.gov (United States)

    Hays, Alexie; Maliski, Ryan; Warner, Benjamin

    2016-07-15

    Family can be a key site of support for individuals who are diagnosed with a health issue, as long as the health condition is known within the family unit. This online experiment investigated variables that influence the likelihood that college students will disclose a hypothetical health issue to a parent. Family communication patterns (FCP) theory informed this analysis by outlining the role of FCP in disclosure dynamics among college students and their parents. Through structural equation modeling, a novel mediation model of FCP demonstrated that conformity indirectly reduced the likelihood to disclose through the constraint on conversation. The sensitivity of the hypothetical health condition did not moderate the relationship of conformity on likelihood to disclose through conversation. However, regardless of FCP, respondents were less likely to disclose sensitive health issues.

  8. Local amino acid sequence patterns dominate the heterogeneous phenotype for the collagen connective tissue disease Osteogenesis Imperfecta resulting from Gly mutations.

    Science.gov (United States)

    Xiao, Jianxi; Yang, Zhangfu; Sun, Xiuxia; Addabbo, Rayna; Baum, Jean

    2015-10-01

    Osteogenesis Imperfecta (OI), a hereditary connective tissue disease in collagen that arises from a single Gly → X mutation in the collagen chain, varies widely in phenotype from perinatal lethal to mild. It is unclear why there is such a large variation in the severity of the disease considering the repeating (Gly-X-Y)n sequence and the uniform rod-like structure of collagen. We systematically evaluate the effect of local (Gly-X-Y)n sequence around the mutation site on OI phenotype using integrated bio-statistical approaches, including odds ratio analysis and decision tree modeling. We show that different Gly → X mutations have different local sequence patterns that are correlated with lethal and nonlethal phenotypes providing a mechanism for understanding the sensitivity of local context in defining lethal and non-lethal OI. A number of important trends about which factors are related to OI phenotypes are revealed by the bio-statistical analyses; most striking is the complementary relationship between the placement of Pro residues and small residues and their correlation to OI phenotype. When Pro is present or small flexible residues are absent nearby a mutation site, the OI case tends to be lethal; when Pro is present or small flexible residues are absent further away from the mutation site, the OI case tends to be nonlethal. The analysis also reveals the dominant role of local sequence around mutation sites in the Major Ligand Binding Regions that are primarily responsible for collagen binding to its receptors and shows that non-lethal mutations are highly predicted by local sequence considerations alone whereas lethal mutations are not as easily predicted and may be a result of more complex interactions. Understanding the sequence determinants of OI mutations will enhance genetic counseling and help establish which steps in the collagen hierarchy to target for drug therapy.

  9. Connected Traveler

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Alex

    2015-11-01

    The Connected Traveler project is a multi-disciplinary undertaking that seeks to validate potential for transformative transportation system energy savings by incentivizing efficient traveler behavior. This poster outlines various aspects of the Connected Traveler project, including market opportunity, understanding traveler behavior and decision-making, automation and connectivity, and a projected timeline for Connected Traveler's key milestones.

  10. Florida Agriculture - Utilizing TRMM to Analyze Sea Breeze Thunderstorm Patterns During El Nino Southern Oscillations and Their Effects Upon Available Fresh Water for South Florida Agricultural Planning and Management

    Science.gov (United States)

    Billiot, Amanda; Lee, Lucas; McKee, Jake; Cooley, Zachary Clayton; Mitchell, Brandie

    2010-01-01

    This project utilizes Tropical Rainfall Measuring Mission (TRMM) and Landsat satellite data to assess the impact of sea breeze precipitation upon areas of agricultural land use in southern Florida. Water is a critical resource to agriculture, and the availability of water for agricultural use in Florida continues to remain a key issue. Recent projections of statewide water use by 2020 estimate that 9.3 billion gallons of water per day will be demanded, and agriculture represents 47% of this demand (Bronson 2003). Farmers have fewer options for water supplies than public users and are often limited to using available supplies from surface and ground water sources which depend in part upon variable weather patterns. Sea breeze thunderstorms are responsible for much of the rainfall delivered to Florida during the wet season (May-October) and have been recognized as an important overall contributor of rainfall in southern Florida (Almeida 2003). TRMM satellite data was used to analyze how sea breeze-induced thunderstorms during El Nino and La Nina affected interannual patterns of precipitation in southern Florida from 1998-2009. TRMM's Precipitation Radar and Microwave Imager provide data to quantify water vapor in the atmosphere, precipitation rates and intensity, and the distribution of precipitation. Rainfall accumulation data derived from TRMM and other microwave sensors were used to analyze the temporal and spatial variations of rainfall during each phase of the El Nino Southern Oscillation (ENSO). Through the use of TRMM and Landsat, slight variations were observed, but it was determined that neither sea breeze nor total rainfall patterns in South Florida were strongly affected by ENSO during the study period. However, more research is needed to characterize the influence of ENSO on summer weather patterns in South Florida. This research will provide the basis for continued observations and study with the Global Precipitation Measurement Mission.

  11. Connections between Frontier Markets

    Directory of Open Access Journals (Sweden)

    Eliza-Olivia Lungu

    2013-06-01

    Full Text Available The global financial system presents a high degree of connectivity and the network theory provides the natural framework for visualizing the structure of it connections. I analyse the financial links established between the frontier markets and how these links evolve over a 10 years period (2001 - 2011. I identify patterns in the network looking both at the node specific statistics (degree, strength and clustering coefficient and at the aggregated network statistics (network density and network asymmetry index.

  12. Coupled Intrinsic Connectivity Distribution analysis: a method for exploratory connectivity analysis of paired FMRI data.

    Directory of Open Access Journals (Sweden)

    Dustin Scheinost

    Full Text Available We present a novel voxel-based connectivity approach for paired functional magnetic resonance imaging (fMRI data collected under two different conditions labeled the Coupled Intrinsic Connectivity Distribution (coupled-ICD. Our proposed method jointly models both conditions to incorporate additional paired information into the connectivity metric. Voxel-based connectivity holds promise as a clinical tool to characterize a wide range of neurological and psychiatric diseases, and monitor their treatment. As such, examining paired connectivity data such as scans acquired pre- and post-intervention is an important application for connectivity methodologically. When presented with data from paired conditions, conventional voxel-based methods analyze each condition separately. However, summarizing each connection separately can misrepresent patterns of changes in connectivity. We show that commonly used methods can underestimate functional changes and subsequently introduce and evaluate our solution to this problem, the coupled-ICD metric, using two studies: 1 healthy controls scanned awake and under anesthesia, and 2 cocaine-dependent subjects and healthy controls scanned while being presented with relaxing or drug-related imagery cues. The coupled-ICD approach detected differences between paired conditions in similar brain regions as the conventional approaches while also revealing additional changes in regions not identified using conventional voxel-based connectivity analyses. Follow-up seed-based analyses on data independent from the voxel-based results also showed connectivity differences between conditions in regions detected by coupled-ICD. This approach of jointly analyzing paired resting-state scans provides a new and important tool with many applications for clinical and basic neuroscience research.

  13. Application of flood-intensity-duration curve, rainfall-intensity-duration curve and time of concentration to analyze the pattern of storms and their corresponding floods for the natural flood events

    Science.gov (United States)

    Kim, Nam Won; Shin, Mun-Ju; Lee, Jeong Eun

    2016-04-01

    The analysis of storm effects on floods is essential step for designing hydraulic structure and flood plain. There are previous studies for analyzing the relationship between the storm patterns and peak flow, flood volume and durations for various sizes of the catchments, but they are not enough to analyze the natural storm effects on flood responses quantitatively. This study suggests a novel method of quantitative analysis using unique factors extracted from the time series of storms and floods to investigate the relationship between natural storms and their corresponding flood responses. We used a distributed rainfall-runoff model of Grid based Rainfall-runoff Model (GRM) to generate the simulated flow and areal rainfall for 50 catchments in Republic of Korea size from 5.6 km2 to 1584.2 km2, which are including overlapped dependent catchments and non-overlapped independent catchments. The parameters of the GRM model were calibrated to get the good model performances of Nash-Sutcliffe efficiency. Then Flood-Intensity-Duration Curve (FIDC) and Rainfall-Intensity-Duration Curve (RIDC) were generated by Flood-Duration-Frequency and Intensity-Duration-Frequency methods respectively using the time series of hydrographs and hyetographs. Time of concentration developed for the Korea catchments was used as a consistent measure to extract the unique factors from the FIDC and RIDC over the different size of catchments. These unique factors for the storms and floods were analyzed against the different size of catchments to investigate the natural storm effects on floods. This method can be easily used to get the intuition of the natural storm effects with various patterns on flood responses. Acknowledgement This research was supported by a grant (11-TI-C06) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

  14. Preschool Connected Speech Inventory.

    Science.gov (United States)

    DiJohnson, Albert; And Others

    This speech inventory developed for a study of aurally handicapped preschool children (see TM 001 129) provides information on intonation patterns in connected speech. The inventory consists of a list of phrases and simple sentences accompanied by pictorial clues. The test is individually administered by a teacher-examiner who presents the spoken…

  15. Simultaneous delta15N, delta13C and delta34S measurements of low-biomass samples using a technically advanced high sensitivity elemental analyzer connected to an isotope ratio mass spectrometer.

    Science.gov (United States)

    Hansen, T; Burmeister, A; Sommer, U

    2009-11-01

    Conventional simultaneous CNS stable isotope abundance measurements of solid samples usually require high sample amounts, up to 1 mg carbon, to achieve exact analytical results. This rarely used application is often impaired by high C:S element ratios when organic samples are analyzed and problems such as incomplete conversion into sulphur dioxide occur during analysis. We introduce, as a technical innovation, a high sensitivity elemental analyzer coupled to a conventional isotope ratio mass spectrometer, with which CNS-stable isotope ratios can be determined simultaneously in samples with low carbon content (<40 microg C corresponding to approximately 100 microg dry weight). The system includes downsized reactors, a temperature program-controlled gas chromatography (GC) column and a cryogenic trap to collect small amounts of sulphur dioxide. This modified application allows for highly sensitive measurements in a fully automated operation with standard deviations better than +/-0.47 per thousand for delta15N and delta34S and +/-0.12 per thousand for delta13C (n = 127). Samples collected from one sampling site in a Baltic fjord within a short time period were measured with the new system to get a first impression of triple stable isotope signatures. The results confirm the potential of using delta34S as a stable isotope tracer in combination with delta15N and delta13C measurements to improve discrimination of food sources in aquatic food webs.

  16. Connective Tissue Disorder

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008349 A clinical analysis of 32 patients with diffuse alveolar hemorrhage in diffuse connective tissue diseases. CHEN Guangxing(陈光星), et al. Dept Rheumatol, PUMC & CAMS Beijing 100730. Chin J Intern Med 2008;47(5):362-365.Objective To provide clues to diagnosis and treatment for diffuse alveolar hemorrhage(DAH)in patients with diffuse connective tissue diseases(CTD).Method To analyze restropectively the data of clinical features,

  17. Relative Clauses in Spectroscopic Articles in the "Physical Review, "Beginnings and 1980: Some Changes in Patterns of Modification and a Connection to a Possible Shift in Style.

    Science.gov (United States)

    Vande Kopple, William J.

    1998-01-01

    Examines the number of relative clauses and percentages of subordinate clauses in two sets of research reports from "Physical Review." Finds a slight decrease in percentages of relative clauses from the first set (1893-1901) to the second (1980). Finds striking differences in patterns of what relative clauses modify. Suggests a stylistic…

  18. Connecting Effective Immune Response, Fluorescent Granzyme B-like Peptide, Specific Peptide Binding Patterns, Patients with Cancer and Viral Infection, in Remission, Clinical Significance, and Liquid Biopsy.

    Science.gov (United States)

    Lo, Wai Chun Jennifer; Luther, Donald Gene

    2016-11-01

    Functional cytotoxic-T-lymphocytes (CTL) with granzyme B play an important role in an effective immune response to tumor growth and infection progression. Tumor cells and platelets in peripheral whole blood smears of cancer patients have shown the presence of innate binding targets for GP1R, a fluorescent synthetic Granzyme B-like peptide. It is not known if similar GP1R-binding targets and specific binding patterns are detectable in peripheral blood of patients with viral infection. It is also not known if a specific binding pattern may be associated with an effective immune response to indicate a favorable prognosis. We reviewed the GP1R-binding patterns in the peripheral blood smears of 5 patients in remission at the time of sampling (3 with cancer and 2 with flu-like symptoms) and a negative control. We show with fluoroscopic images that there are: 1) fluorescent GP1R-binding targets mostly in the cytoplasmic areas of nucleated cells in patients with breast and lung cancer who have longer survival, 2) intense fluorescent deposits mostly in the nuclear areas of segmented neutrophils in patients recovered from severe to mild flu-like symptoms, 3) discernible fluorescent deposits in the cytoplasmic areas of small lymphocyte-like elements and overall intense fluorescent stain in large cells in the patient with advanced pancreatic cancer who had shorter survival, 4) GP1R-binding targets in numerous platelet-like elements in all 5 patients. The control sample did not show similar binding patterns. The potential association between specific GP1R-binding patterns in peripheral blood samples and prognostic significance, and its use as liquid biopsy are discussed.

  19. About Connections

    Directory of Open Access Journals (Sweden)

    Kathleen S Rockland

    2015-05-01

    Full Text Available Despite the attention attracted by connectomics, one can lose sight of the very real questions concerning What are connections? In the neuroimaging community, structural connectivity is ground truth and underlying constraint on functional or effective connectivity. It is referenced to underlying anatomy; but, as increasingly remarked, there is a large gap between the wealth of human brain mapping and the relatively scant data on actual anatomical connectivity. Moreover, connections have typically been discussed as pairwise, point x projecting to point y (or: to points y and z, or more recently, in graph theoretical terms, as nodes or regions and the interconnecting edges. This is a convenient shorthand, but tends not to capture the richness and nuance of basic anatomical properties as identified in the classic tradition of tracer studies. The present short review accordingly revisits connectional weights, heterogeneity, reciprocity, topography, and hierarchical organization, drawing on concrete examples. The emphasis is on presynaptic long-distance connections, motivated by the intention to probe current assumptions and promote discussions about further progress and synthesis.

  20. Deep neural network with weight sparsity control and pre-training extracts hierarchical features and enhances classification performance: Evidence from whole-brain resting-state functional connectivity patterns of schizophrenia.

    Science.gov (United States)

    Kim, Junghoe; Calhoun, Vince D; Shim, Eunsoo; Lee, Jong-Hwan

    2016-01-01

    Functional connectivity (FC) patterns obtained from resting-state functional magnetic resonance imaging data are commonly employed to study neuropsychiatric conditions by using pattern classifiers such as the support vector machine (SVM). Meanwhile, a deep neural network (DNN) with multiple hidden layers has shown its ability to systematically extract lower-to-higher level information of image and speech data from lower-to-higher hidden layers, markedly enhancing classification accuracy. The objective of this study was to adopt the DNN for whole-brain resting-state FC pattern classification of schizophrenia (SZ) patients vs. healthy controls (HCs) and identification of aberrant FC patterns associated with SZ. We hypothesized that the lower-to-higher level features learned via the DNN would significantly enhance the classification accuracy, and proposed an adaptive learning algorithm to explicitly control the weight sparsity in each hidden layer via L1-norm regularization. Furthermore, the weights were initialized via stacked autoencoder based pre-training to further improve the classification performance. Classification accuracy was systematically evaluated as a function of (1) the number of hidden layers/nodes, (2) the use of L1-norm regularization, (3) the use of the pre-training, (4) the use of framewise displacement (FD) removal, and (5) the use of anatomical/functional parcellation. Using FC patterns from anatomically parcellated regions without FD removal, an error rate of 14.2% was achieved by employing three hidden layers and 50 hidden nodes with both L1-norm regularization and pre-training, which was substantially lower than the error rate from the SVM (22.3%). Moreover, the trained DNN weights (i.e., the learned features) were found to represent the hierarchical organization of aberrant FC patterns in SZ compared with HC. Specifically, pairs of nodes extracted from the lower hidden layer represented sparse FC patterns implicated in SZ, which was

  1. Gendered Connections

    DEFF Research Database (Denmark)

    Jensen, Steffen Bo

    2009-01-01

    This article explores the gendered nature of urban politics in Cape Town by focusing on a group of female, township politicians. Employing the Deleuzian concept of `wild connectivity', it argues that these politically entrepreneurial women were able to negotiate a highly volatile urban landscape...... space also drew on quite traditional notions of female respectability. Furthermore, the article argues, the form of wild connectivity to an extent was a function of the political transition, which destabilized formal structures of gendered authority. It remains a question whether this form...... of connectivity might endure, as Capetonian politics assumes a post-apartheid structure....

  2. Unique gene expression and MR T2 relaxometry patterns define chronic murine dextran sodium sulphate colitis as a model for connective tissue changes in human Crohn's disease.

    Directory of Open Access Journals (Sweden)

    Christine Breynaert

    Full Text Available INTRODUCTION: Chronically relapsing inflammation, tissue remodeling and fibrosis are hallmarks of inflammatory bowel diseases. The aim of this study was to investigate changes in connective tissue in a chronic murine model resulting from repeated cycles of dextran sodium sulphate (DSS ingestion, to mimic the relapsing nature of the human disease. MATERIALS AND METHODS: C57BL/6 mice were exposed to DSS in drinking water for 1 week, followed by a recovery phase of 2 weeks. This cycle of exposure was repeated for up to 3 times (9 weeks in total. Colonic inflammation, fibrosis, extracellular matrix proteins and colonic gene expression were studied. In vivo MRI T 2 relaxometry was studied as a potential non-invasive imaging tool to evaluate bowel wall inflammation and fibrosis. RESULTS: Repeated cycles of DSS resulted in a relapsing and remitting disease course, which induced a chronic segmental, transmural colitis after 2 and 3 cycles of DSS with clear induction of fibrosis and remodeling of the muscular layer. Tenascin expression mirrored its expression in Crohn's colitis. Microarray data identified a gene expression profile different in chronic colitis from that in acute colitis. Additional recovery was associated with upregulation of unique genes, in particular keratins, pointing to activation of molecular pathways for healing and repair. In vivo MRI T2 relaxometry of the colon showed a clear shift towards higher T2 values in the acute stage and a gradual regression of T2 values with increasing cycles of DSS. CONCLUSIONS: Repeated cycles of DSS exposure induce fibrosis and connective tissue changes with typical features, as occurring in Crohn's disease. Colonic gene expression analysis revealed unique expression profiles in chronic colitis compared to acute colitis and after additional recovery, pointing to potential new targets to intervene with the induction of fibrosis. In vivo T2 relaxometry is a promising non-invasive assessment of

  3. HR Connect

    Data.gov (United States)

    US Agency for International Development — HR Connect is the USAID HR personnel system which allows HR professionals to process HR actions related to employee's personal and position information. This system...

  4. Emergence of spatial behavioral function and associated mossy fiber connectivity and c-Fos labeling patterns in the hippocampus of rats [v1; ref status: indexed, http://f1000r.es/5nr

    Directory of Open Access Journals (Sweden)

    Rachel Comba

    2015-07-01

    Full Text Available Improvement on spatial tasks is observed during a late, postnatal developmental period (PND18 – PND24.  The purpose of the current work was 1 to determine whether the emergence of spatial-behavioral function was based on the ability to generate appropriate behavioral output; 2 to assess whether mossy fiber connectivity patterns preceded the emergence of spatial-behavioral function; 3 to explore functional changes in the hippocampus to determine whether activity in hippocampal networks occurred in a training-dependent or developmentally-dependent fashion.  To these ends, male, Long Evans rats were trained on a spatial water or dry maze task for one day (PND16, PND18 or PND20 then euthanized.  Training on these 2 tasks with opposing behavioral demands (swimming versus exploration was hypothesized to control for behavioral topology.  Only at PND20 was there evidence of spatial-behavioral function for both tasks.  Examination of synaptophysin staining in the CA3 region (i.e., mossy fiber projections revealed enhanced connectivity patterns that preceded the emergence of spatial behavior.  Analysis of c-Fos labeling (functional changes revealed developmentally-dependent increases in c-Fos positive cells in the dentate gyrus, CA3 and CA1 regions whereas training-dependent increases were noted in the CA3 and CA1 regions for the water-maze trained groups.  Results suggest that changes in mossy fiber connectivity in association with enhanced hippocampal functioning precede the emergence of spatial behavior observed at PND20.  The combination of neuroanatomical and behavioural results confirms the hypothesis that this time represents a sensitive period for hippocampal development and modification and the emergence of spatial/ cognitive function.

  5. 大病医疗保险补偿模式及补偿效果分析——以L市为例%Analyze compensation patterns and compensation effects of catastrophic disease insurance in L City

    Institute of Scientific and Technical Information of China (English)

    项莉; 罗会秋; 潘瑶; 李聪; 张颖

    2015-01-01

    目的:分析西部L市农村居民大病医疗保险补偿模式及补偿效果,为完善和推广科学的大病医疗保险补偿模式提出可行性建议. 方法:对补偿模式进行政策分析,运用受益率、患者自付费用、实际补偿比等指标分析大病医疗保险实施效果. 结果:2013年L市大病医疗保险受益率为3. 2%,基金使用率为92%,不同区县基金使用率差异较大. 实行大病保险后患者自付费用下降明显,该市大病医疗保险和新农合累计实际补偿比达到84. 8%,其中新农合实际补偿比已达68. 9%,但同时新农合基金出现赤字. 结论与建议:科学设置起付线、补偿比例、补偿范围,取消封顶线,完善大病医疗保险补偿方案;采取措施减少大病医疗保险地市统筹带来的各区县之间的不公平;实现大病医疗保险补偿模式和新农合补偿模式的有效衔接.%Objective:This paper designs to analyze compensation patterns and compensation effects of cata-strophic disease insurance in L City, and put forward feasible suggestions to improve the compensation patterns of cat-astrophic disease insurance. Methods:We combined the relevant policy documents to analyze compensation patterns, and used benefit rate, OOP and The effective reimbursement rate to analyze compensation effects of catastrophic dis-ease insurance. Results:Catastrophic disease insurance benefit rate in L city in 2013 was 3. 2%; Rates of NCMS fund unilization was 92%, which diversed from county to county. Patients' OOP decreased significantly after reim-bursement of catastrophic disease insurance;Catastrophic disease insurance and NCMS total effective reimbursement rate reached 84.8%;The NCMS compensation rate reached 68. 9%, while fund incurred a financial deficit at the same time. Conclusion:Set deductibles, compensation rate and compensation range scientifically, and cancel ceiling level,improve the program of catastrophic disease insurance. Take measures to reduce the

  6. Polyhedral patterns

    KAUST Repository

    Jiang, Caigui

    2015-10-27

    We study the design and optimization of polyhedral patterns, which are patterns of planar polygonal faces on freeform surfaces. Working with polyhedral patterns is desirable in architectural geometry and industrial design. However, the classical tiling patterns on the plane must take on various shapes in order to faithfully and feasibly approximate curved surfaces. We define and analyze the deformations these tiles must undertake to account for curvature, and discover the symmetries that remain invariant under such deformations. We propose a novel method to regularize polyhedral patterns while maintaining these symmetries into a plethora of aesthetic and feasible patterns.

  7. Functional connectivity changes detected with magnetoencephalography after mild traumatic brain injury.

    Science.gov (United States)

    Dimitriadis, Stavros I; Zouridakis, George; Rezaie, Roozbeh; Babajani-Feremi, Abbas; Papanicolaou, Andrew C

    2015-01-01

    Mild traumatic brain injury (mTBI) may affect normal cognition and behavior by disrupting the functional connectivity networks that mediate efficient communication among brain regions. In this study, we analyzed brain connectivity profiles from resting state Magnetoencephalographic (MEG) recordings obtained from 31 mTBI patients and 55 normal controls. We used phase-locking value estimates to compute functional connectivity graphs to quantify frequency-specific couplings between sensors at various frequency bands. Overall, normal controls showed a dense network of strong local connections and a limited number of long-range connections that accounted for approximately 20% of all connections, whereas mTBI patients showed networks characterized by weak local connections and strong long-range connections that accounted for more than 60% of all connections. Comparison of the two distinct general patterns at different frequencies using a tensor representation for the connectivity graphs and tensor subspace analysis for optimal feature extraction showed that mTBI patients could be separated from normal controls with 100% classification accuracy in the alpha band. These encouraging findings support the hypothesis that MEG-based functional connectivity patterns may be used as biomarkers that can provide more accurate diagnoses, help guide treatment, and monitor effectiveness of intervention in mTBI.

  8. Spawning areas of eastern Baltic cod revisited: Using hydrodynamic modelling to reveal spawning habitat suitability, egg survival probability, and connectivity patterns

    Science.gov (United States)

    Hinrichsen, H.-H.; Lehmann, A.; Petereit, C.; Nissling, A.; Ustups, D.; Bergström, U.; Hüssy, K.

    2016-04-01

    In the highly variable environment of the Baltic Sea two genetically distinct cod stocks exist, one west of the island of Bornholm, which is referred to as the western stock, and one to the east of Bornholm, the eastern stock. A hydrodynamic model combined with a Lagrangian particle tracking technique was utilised to provide spatially and temporally resolved long-term information on environmentally-related (i) spawning habitat size, (ii) egg/yolk-sac larval survival, (iii) separation of causes of mortality, and (iv) connectivity between spawning areas of eastern Baltic cod. Simulations were performed to quantify processes generating heterogeneity in spatial distribution of cod eggs and yolk sac larvae up to the first-feeding stage. The spatial extent of cod eggs represented as virtual drifters is primarily determined by oxygen and salinity conditions at spawning, which define the habitat requirement to which cod's physiology is suited for egg development. The highest habitat suitability occurred in the Bornholm Basin, followed by the Gdansk Deep, while relatively low habitat suitability was obtained for the Arkona and the Gotland Basin. During drift egg and yolk sac larval survival is to a large extent affected by sedimentation. Eggs initially released in the western spawning grounds (Arkona and Bornholm Basin) were more affected by sedimentation than those released in the eastern spawning grounds (Gdansk Deep and Gotland Basin). Highest relative survival of eastern Baltic cod eggs occurred in the Bornholm Basin, with a pronounced decrease towards the Gdansk Deep and the Gotland Basin. Relatively low survival rates in the Gdansk Deep and in the Gotland Basin were attributable to oxygen-dependent mortality. Low oxygen content had almost no impact on survival in the Arkona Basin. For all spawning areas temperature dependent mortality was only evident after severe winters. Egg buoyancy in relation to topographic features like bottom sills and strong bottom slopes

  9. Connectivity pattern differences bilaterally in the cerebellum posterior lobe in healthy subjects after normal sleep and sleep deprivation: a resting-state functional MRI study

    Directory of Open Access Journals (Sweden)

    Liu XM

    2015-05-01

    Full Text Available Xuming Liu,1 Zhihan Yan,2 Tingyu Wang,1 Xiaokai Yang,1 Feng Feng,3 Luping Fan,1 Jian Jiang4 1Department of Radiology, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, 2Department of Radiology, The 2nd Affiliated Hospital of Wenzhou Medical University, Wenzhou, 3Peking Union Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 4Department of Radiology, The First Affiliated Hospital of Nanchang University, Nanchang, People’s Republic of China Objective: The aim of this study was to use functional magnetic resonance imaging (fMRI technique to explore the resting-state functional connectivity (rsFC differences of the bilaterial cerebellum posterior lobe (CPL after normal sleep (NS and after sleep deprivation (SD. Methods: A total of 16 healthy subjects (eight males, eight females underwent an fMRI scan twice at random: once following NS and the other following 24 hours’ SD, with an interval of 1 month between the two scans. The fMRI scanning included resting state and acupuncture stimulation. The special activated regions located during the acupuncture stimulation were selected as regions of interest for rsFC analysis. Results: Bilateral CPLs were positively activated by acupuncture stimulation. In the NS group, the left CPL showed rsFC with the bilateral CPL, bilateral frontal lobe (BFL, left precuneus and right inferior parietal lobule, while the right CPL showed rsFC with the bilateral temporal lobe, right cerebellum anterior lobe, right CPL, left frontal lobe, left anterior cingulate, right posterior cingulate, and bilateral inferior parietal lobule. In the SD group, the left CPL showed rsFC with the left posterior cingulate gyrus bilateral CPL, left precuneus, left precentral gyrus, BFL, and the left parietal lobe, while the right CPL showed rsFC with bilateral cerebellum anterior lobe, bilateral CPL, left frontal lobe and left temporal lobe. Compared with the NS group, the

  10. Effect of Integrated Cognitive Therapy on Hippocampal Functional Connectivity Patterns in Stroke Patients with Cognitive Dysfunction: A Resting-State fMRI Study

    Directory of Open Access Journals (Sweden)

    Shanli Yang

    2014-01-01

    Full Text Available Objective. This study aimed to identify abnormal hippocampal functional connectivity (FC following ischemic stroke using resting-state fMRI. We also explored whether abnormal hippocampal FC could be modulated by integrated cognitive therapy and tested whether these alterations were associated with cognitive performance. Methods. 18 right-handed cognitively impaired ischemic stroke patients and 18 healty control (HC subjects were included in this study. Stroke subjects were scanned at baseline and after integrated cognitive therapy, while HCs were only scanned at baseline, to identify regions that show significant correlations with the seed region. Behavioral and cognitive assessments were obtained before each scan. Results. During the resting state, we found abnormal hippocampal FC associated with temporal regions, insular cortex, cerebellum, and prefrontal cortex in stroke patients compared to HCs. After integrated cognitive therapy, however, the stroke group showed increased hippocampal FC mainly located in the prefrontal gyrus and the default mode network (DMN. Altered hippocampal FC was associated with cognitive improvement. Conclusion. Resting-state fMRI may provide novel insight into the study of functional networks in the brain after stroke. Furthermore, altered hippocampal FC may be a compensatory mechanism for cognitive recovery after ischemic stroke.

  11. Dynamic effective connectivity of inter-areal brain circuits.

    Directory of Open Access Journals (Sweden)

    Demian Battaglia

    Full Text Available Anatomic connections between brain areas affect information flow between neuronal circuits and the synchronization of neuronal activity. However, such structural connectivity does not coincide with effective connectivity (or, more precisely, causal connectivity, related to the elusive question "Which areas cause the present activity of which others?". Effective connectivity is directed and depends flexibly on contexts and tasks. Here we show that dynamic effective connectivity can emerge from transitions in the collective organization of coherent neural activity. Integrating simulation and semi-analytic approaches, we study mesoscale network motifs of interacting cortical areas, modeled as large random networks of spiking neurons or as simple rate units. Through a causal analysis of time-series of model neural activity, we show that different dynamical states generated by a same structural connectivity motif correspond to distinct effective connectivity motifs. Such effective motifs can display a dominant directionality, due to spontaneous symmetry breaking and effective entrainment between local brain rhythms, although all connections in the considered structural motifs are reciprocal. We show then that transitions between effective connectivity configurations (like, for instance, reversal in the direction of inter-areal interactions can be triggered reliably by brief perturbation inputs, properly timed with respect to an ongoing local oscillation, without the need for plastic synaptic changes. Finally, we analyze how the information encoded in spiking patterns of a local neuronal population is propagated across a fixed structural connectivity motif, demonstrating that changes in the active effective connectivity regulate both the efficiency and the directionality of information transfer. Previous studies stressed the role played by coherent oscillations in establishing efficient communication between distant areas. Going beyond these early

  12. Effects of brain-derived neurotrophic factor on cell survival, differentiation and patterning of neuronal connections and Müller glia cells in the developing retina.

    Science.gov (United States)

    Pinzón-Duarte, Germán; Arango-González, Blanca; Guenther, Elke; Kohler, Konrad

    2004-03-01

    The aim of the present study was to determine the influence of brain-derived neurotrophic factor (BDNF) on survival, phenotype differentiation and network formation of retinal neurons and glia cells. To achieve a defined concentration and constant level of BDNF over several days, experiments were performed in an organotypic culture of the developing rat retina. After 6 days in vitro, apoptosis in the different cell layers was determined by TUNEL staining and cell-type-specific antibodies were used to identify distinct neuronal cell types and Müller cells. Cultured retinas treated with BDNF (100 ng BDNF/mL medium) were compared with untreated as well as with age-matched in vivo retinas. Quantitative morphometry was carried out using confocal microscopy. BDNF promoted the in vitro development and differentiation of the retina in general, i.e. the number of cells in the nuclear layers and the thickness of the plexiform layers were increased. For all neurons, the number of cells and the complexity of arborizations in the synaptic layers were clearly up-regulated by BDNF. In control cultures, the synaptic stratification of cone bipolar cells within the On- and Off-layer of the inner plexiform layer was disturbed and a strong reactivity of Müller cell glia was observed. These effects were not present in BDNF-treated cultures. Our data show that BDNF promotes the survival of retinal interneurons and plays an important role in establishing the phenotypes and the synaptic connections of a large number of neuronal types in the developing retina. Moreover, we show an effect of BDNF on Müller glia cells.

  13. Revisiting city connectivity

    NARCIS (Netherlands)

    Mans, U.

    2014-01-01

    This article introduces a new perspective on city connectivity in order to analyze non-hub cities and their position in the world economy. The author revisits the different approaches discussed in the Global Commodity Chains (GCC), Global Production Networks (GPN) and World City Network (WCN) discou

  14. Broad-scale sampling of primary freshwater fish populations reveals the role of intrinsic traits, inter-basin connectivity, drainage area and latitude on shaping contemporary patterns of genetic diversity.

    Science.gov (United States)

    Sousa-Santos, Carla; Robalo, Joana I; Pereira, Ana M; Branco, Paulo; Santos, José Maria; Ferreira, Maria Teresa; Sousa, Mónica; Doadrio, Ignacio

    2016-01-01

    Background. Worldwide predictions suggest that up to 75% of the freshwater fish species occurring in rivers with reduced discharge could be extinct by 2070 due to the combined effect of climate change and water abstraction. The Mediterranean region is considered to be a hotspot of freshwater fish diversity but also one of the regions where the effects of climate change will be more severe. Iberian cyprinids are currently highly endangered, with over 68% of the species raising some level of conservation concern. Methods. During the FISHATLAS project, the Portuguese hydrographical network was extensively covered (all the 34 river basins and 47 sub-basins) in order to contribute with valuable data on the genetic diversity distribution patterns of native cyprinid species. A total of 188 populations belonging to 16 cyprinid species of Squalius, Luciobarbus, Achondrostoma, Iberochondrostoma, Anaecypris and Pseudochondrostoma were characterized, for a total of 3,678 cytochrome b gene sequences. Results. When the genetic diversity of these populations was mapped, it highlighted differences among populations from the same species and between species with identical distribution areas. Factors shaping the contemporary patterns of genetic diversity were explored and the results revealed the role of latitude, inter-basin connectivity, migratory behaviour, species maximum size, species range and other species intrinsic traits in determining the genetic diversity of sampled populations. Contrastingly, drainage area and hydrological regime (permanent vs. temporary) seem to have no significant effect on genetic diversity. Species intrinsic traits, maximum size attained, inter-basin connectivity and latitude explained over 30% of the haplotype diversity variance and, generally, the levels of diversity were significantly higher for smaller sized species, from connected and southerly river basins. Discussion. Targeting multiple co-distributed species of primary freshwater fish allowed

  15. Connected Traveler

    Energy Technology Data Exchange (ETDEWEB)

    2016-06-01

    The Connected Traveler framework seeks to boost the energy efficiency of personal travel and the overall transportation system by maximizing the accuracy of predicted traveler behavior in response to real-time feedback and incentives. It is anticipated that this approach will establish a feedback loop that 'learns' traveler preferences and customizes incentives to meet or exceed energy efficiency targets by empowering individual travelers with information needed to make energy-efficient choices and reducing the complexity required to validate transportation system energy savings. This handout provides an overview of NREL's Connected Traveler project, including graphics, milestones, and contact information.

  16. GSM Trace Quality Analyzer (TQA) software

    OpenAIRE

    Blanchart Forne, Marc

    2016-01-01

    Connectivity is now the must-have service for enhancing passenger experience. To proof and also to show to the customers the quality of the connectivity system an user friendly mock-up has to be designed. A packet analyzer software designed to validate an existing SATCOM simulator and to improve future airline architecture networks.

  17. Getting Connected

    Science.gov (United States)

    Larkin, Patrick

    2011-01-01

    That the world outside schools is changing faster than ever is old news. Unfortunately, that the world "inside" schools is changing at a glacial pace is even older news. As school leaders, principals have an important choice to make as they move into the second decade of the 21st century. School leaders have a moral obligation to connect and…

  18. The Reading/Writing Connection.

    Science.gov (United States)

    Anderson, Nancy Comfort

    1998-01-01

    Discusses ways to motivate children to become readers and writers, characteristics of good children's literature, using patterned books as models, and prewriting activities; provides an annotated bibliography of 26 patterned books to encourage the reading/writing connection. A subset of updated folk and fairy tales is included. (LRW)

  19. Order-theoretical connectivity

    Directory of Open Access Journals (Sweden)

    T. A. Richmond

    1990-01-01

    Full Text Available Order-theoretically connected posets are introduced and applied to create the notion of T-connectivity in ordered topological spaces. As special cases T-connectivity contains classical connectivity, order-connectivity, and link-connectivity.

  20. Inferring Neuronal Network Connectivity using Time-constrained Episodes

    CERN Document Server

    Patnaik, Debprakash; Unnikrishnan, K P

    2007-01-01

    Discovering frequent episodes in event sequences is an interesting data mining task. In this paper, we argue that this framework is very effective for analyzing multi-neuronal spike train data. Analyzing spike train data is an important problem in neuroscience though there are no data mining approaches reported for this. Motivated by this application, we introduce different temporal constraints on the occurrences of episodes. We present algorithms for discovering frequent episodes under temporal constraints. Through simulations, we show that our method is very effective for analyzing spike train data for unearthing underlying connectivity patterns.

  1. Convergence Patterns in Latin America

    DEFF Research Database (Denmark)

    Quiroga, Paola Andrea Barrientos

    Literature on convergence among Latin American countries is still scarce compared to other regions. Moreover, almost none of the research connects convergence to the economic history of Latin America and the usual finding is one speed of convergence. In this paper I analyze 32 countries and 108...... years, more observations than any other study. This long span of data allows me to use economic history to explain, analyze, validate, and understand the results of convergence patterns in the region. I find more than one speed of convergence (clubs) related to the known historical background, country...

  2. Specialization Patterns

    DEFF Research Database (Denmark)

    Schultz, Ulrik Pagh; Lawall, Julia Laetitia; Consel, Charles

    2000-01-01

    Design patterns offer many advantages for software development, but can introduce inefficiency into the final program. Program specialization can eliminate such overheads, but is most effective when targeted by the user to specific bottlenecks. Consequently, we propose that these concepts...... are complementary. Program specialization can optimize programs written using design patterns, and design patterns provide information about the program structure that can guide specialization. Concretely, we propose specialization patterns, which describe how to apply program specialization to optimize uses...... of design patterns. In this paper, we analyze the specialization opportunities provided by specific uses of design patterns. Based on the analysis of each design pattern, we define the associated specialization pattern. These specialization opportunities can be declared using the specialization classes...

  3. Downhole Fluid Analyzer Development

    Energy Technology Data Exchange (ETDEWEB)

    Bill Turner

    2006-11-28

    A novel fiber optic downhole fluid analyzer has been developed for operation in production wells. This device will allow real-time determination of the oil, gas and water fractions of fluids from different zones in a multizone or multilateral completion environment. The device uses near infrared spectroscopy and induced fluorescence measurement to unambiguously determine the oil, water and gas concentrations at all but the highest water cuts. The only downhole components of the system are the fiber optic cable and windows. All of the active components--light sources, sensors, detection electronics and software--will be located at the surface, and will be able to operate multiple downhole probes. Laboratory testing has demonstrated that the sensor can accurately determine oil, water and gas fractions with a less than 5 percent standard error. Once installed in an intelligent completion, this sensor will give the operating company timely information about the fluids arising from various zones or multilaterals in a complex completion pattern, allowing informed decisions to be made on controlling production. The research and development tasks are discussed along with a market analysis.

  4. Analyzing Spatiotemporal Patterns of Meteorological Drought and Its Responses to Climate Change Across Northeast China%气候变化背景下东北地区气象干旱的时空演变特征

    Institute of Scientific and Technical Information of China (English)

    卢洪健; 莫兴国; 孟德娟; 刘苏峡

    2015-01-01

    In order to capture the spatiotemporal patterns of drought vulnerability and predict its response char-acteristics to climate change in Northeast China (NEC), observed precipitation data sets of 98 meteorological stations in 1961-2010 and output datasets of the WCRP coupled multi-model (CMIP3) for IPCC SRES A1B, A2 and B1 climate change scenarios during 2011-2060 were engaged to calculate the commonly used Standard-ized Precipitation Index, which analyzed with the popular methods of Mann-Kendall detection, Empirical Or-thogonal Function and Wavelet transformation. The main results can be concluded as following. Historical drought-wetness evolution in NEC could be properly detected by the SPI series, and drought severity in most areas significantly increased during last 50 years especially on the 12-month timescale. While drought condi-tions in southern part and Liao River basin in NEC are always most serious, the first four EOF loadings on dif-ferent time steps show a similar distribution pattern with some local differences. The drought spatial coverage took on an obviously increasing trend accompanied with drastic inter-annual and inter-decadal fluctuations, and the dominant period were differently identified for the south (11a) and the north (3.5 a). Under the three cli-mate change scenarios, the period of the early 30 years would share most of the mega droughts during 2011-2060, and the A2 scenario may own more frequently and severe drought events than others;more impor-tantly, the drought core may migrate northward to some extent.%基于中国东北地区98个气象站点历史数据和WCRP多模式耦合CMIP3输出的IPCC SRES A1B、A2和B1气候变化情景下的降雨资料,计算3、6、12和24个月尺度上的标准化降水指数(SPI),结合M-K检测、EOF分解和小波分析,研究东北地区干旱的时空变化格局及其对气候变化的响应特征.结果表明:①SPI能较好地检测东北地区干湿变化状况,4个时间尺度上主要的

  5. Population Structure, Genetic Diversity, Effective Population Size, Demographic History and Regional Connectivity Patterns of the Endangered Dusky Grouper, Epinephelus marginatus (Teleostei: Serranidae), within Malta’s Fisheries Management Zone

    Science.gov (United States)

    Vella, Adriana

    2016-01-01

    The objective of this study is to describe the genetic population structure and demographic history of the endangered marine fish, Epinephelus marginatus, within Malta’s Fisheries Management Zone for the purpose of localised conservation planning. Epinephelus marginatus is a long-lived, sedentary, reef-associated protogynous hermaphrodite with high commercial and recreational value that is at risk of extinction throughout its global distribution. Based on global trends, population substructuring and gaps in local knowledge this has led to an increased interest in evaluation of local stock. Assessment of Maltese demography was based on historical and contemporary catch landings data whilst genetic population structure and regional connectivity patterns were evaluated by examining 175 individuals collected within the central Mediterranean region between 2002 and 2009 using 14 nuclear microsatellite loci. Demographic stock assessment of Maltese E. marginatus’ revealed a 99% decline in catch landings between 1947 and 2009 within the Fisheries Management Zone. A contemporary modest mean size was observed, 3 ± 3 kg, where approximately 17% of the population was juvenile, 68% female/sex-changing and 15% were male with a male-to-female sex ratio of 1:5. Genetic analysis describes the overall population of E. marginatus’ within the Fisheries Management Zone as decreasing in size (ƟH = 2.2), which has gone through a significant size reduction in the past (M = 0.41) and consequently shows signs of moderate inbreeding (FIS = 0.10, p < 0.001) with an estimated effective population size of 130 individuals. Results of spatially explicit Bayesian genetic cluster analysis detected two geographically distinct subpopulations within Malta’s Fisheries Management Zone and that they are connected to a larger network of E. marginatus’ within the Sicily Channel. Results suggest conservation management should be designed to reflect E. marginatus’ within Malta’s Fisheries

  6. Fuel analyzer; Analisador de combustiveis

    Energy Technology Data Exchange (ETDEWEB)

    Cozzolino, Roberval [RS Motors, Indaiatuba, SP (Brazil)

    2008-07-01

    The current technology 'COMBUSTIMETRO' aims to examine the fuel through performance of the engine, as the role of the fuel is to produce energy for the combustion engine in the form of which is directly proportional to the quality and type of fuel. The 'COMBUSTIMETRO' has an engine that always keeps the same entry of air, fuel and fixed point of ignition. His operation is monitored by sensors (Sonda Lambda, RPM and Gases Analyzer) connected to a processor that performs calculations and records the information, generate reports and graphs. (author)

  7. Connecting dots

    DEFF Research Database (Denmark)

    Murakami, Kyoko; Jacobs, Rachel L.

    2017-01-01

    of connecting the dots of recalled moments of individual family members lives and is geared towards building a family’s shared future for posterity. Lastly, we consider a wider implication of family reminiscence in terms of human development. http://www.infoagepub.com/products/Memory-Practices-and-Learning...... and Middleton, 1995). A reminiscence conversation is a dynamic talk-in-interaction, which can produce valuable learning experience for the participants involved. Reminiscence talk contains rich, personal, historic data that can reveal and inform family members of an unknown past. In this seminar/chapter, we...... shall present a discursive approach, a methodology that captures the dynamics of reminiscence. We analyse collected conversational data of British family members reminiscing on their past as a joint family activity. Through such talk-in-interaction, the family members develop continuity within...

  8. Dense neuron clustering explains connectivity statistics in cortical microcircuits.

    Directory of Open Access Journals (Sweden)

    Vladimir V Klinshov

    Full Text Available Local cortical circuits appear highly non-random, but the underlying connectivity rule remains elusive. Here, we analyze experimental data observed in layer 5 of rat neocortex and suggest a model for connectivity from which emerge essential observed non-random features of both wiring and weighting. These features include lognormal distributions of synaptic connection strength, anatomical clustering, and strong correlations between clustering and connection strength. Our model predicts that cortical microcircuits contain large groups of densely connected neurons which we call clusters. We show that such a cluster contains about one fifth of all excitatory neurons of a circuit which are very densely connected with stronger than average synapses. We demonstrate that such clustering plays an important role in the network dynamics, namely, it creates bistable neural spiking in small cortical circuits. Furthermore, introducing local clustering in large-scale networks leads to the emergence of various patterns of persistent local activity in an ongoing network activity. Thus, our results may bridge a gap between anatomical structure and persistent activity observed during working memory and other cognitive processes.

  9. 注意缺陷多动障碍儿童的右侧颞顶叶联合部全脑功能连接特征%Abnormal patterns of functional connectivity between right temporal parietal junction and whole brain in children with attention deficit hyperactivity disorder

    Institute of Scientific and Technical Information of China (English)

    王苏文; 邢伟; 陈杰; 王娜; 王苏弘

    2015-01-01

    matched controls from a normal primary school over the same period, and then,blood oxygenation level dependent(BOLD) signal was acquired to calculate the functional connectivity of rTPJ with other brain regions.Significant differences of connectivity intra-class and between groups were analyzed.Also, the correlation between the connectivity strength and the ADHD rating scales were tested.Results The pattern of functional connectivity of the rTPJ for the ADHD group was similar to that of the normal control group.Compared with the normal controls, the left superior temporal gyrus (MNI coordinates-33,6,48) , the right anterior c ingulate coltex(MNI coordinates 6,39,-3) , the right inferior parietal lobule (MNI coordinates 42,-33,30) , the left medial frontal gyrus(MNI coordinates-3,63,-18) in children with ADHD sbowed an increased resting-state functional connectivity with the whole brain ,while the right middle temporal gyrus(MNI coordinates 57,-33,-12) , the right cingulate gyrus(MNI coordinates 18,-21,36) showed a decreased resting-state functional connectivity with the whole brain.The average connection strength between the rTPJ and the whole brain showed positive correlation with the ADHD scores,while in normal controls,it showed negative.The connection strength between the rTPJ and those 6 brain areas with significant statistical difference was relevant to the ADHD scores,but they had no statistical significance.Conclusion The functional connection abnormalities between tbc rTPJ and the whole brain in children with ADHD may be relevant to the clinical symptom of attention-deficit.

  10. Performance of Series Connected GaAs Photovoltaic Converters under Multimode Optical Fiber Illumination

    Directory of Open Access Journals (Sweden)

    Tiqiang Shan

    2014-01-01

    Full Text Available In many military and industrial applications, GaAs photovoltaic (PV converters are connected in series in order to generate the required voltage compatible with most common electronics. Multimode optical fibers are usually used to carry high-intensity laser and illuminate the series connected GaAs PV converters in real time. However, multimode optical fiber illumination has a speckled intensity pattern. The series connected PV array is extremely sensitive to nonuniform illumination; its performance is limited severely by the converter that is illuminated the least. This paper quantifies the effects of multimode optical fiber illumination on the performance of series connected GaAs PV converters, analyzes the loss mechanisms due to speckles, and discusses the maximum illumination efficiency. In order to describe the illumination dependent behavior detailedly, modeling of the series connected PV array is accomplished based on the equivalent circuit for PV cells. Finally, a series of experiments are carried out to demonstrate the theory analysis.

  11. Analyzing on the Marxism Theoretical Foundation of Low-Carbon Consumption Patterns%低碳消费模式的马克思主义理论分析

    Institute of Scientific and Technical Information of China (English)

    高晓峰; 李新慧

    2012-01-01

    目前,低碳消费已成为国内学术界的研究热点问题,但对低碳消费模式的研究还很少.文章认为,低碳消费模式是指消费者适应低碳经济的要求而建立的低碳消费关系和低碳消费行为规范的综合表现,它从总体上反映人们低碳消费行为的主要内容、基本态势和质的规定性,是指导人们进行低碳消费活动,并对人们进行社会价值判断的理论概括和依据.马克思主义消费理论和马克思主义自然观共同构成了低碳消费模式的马克思主义理论基础.马克思主义对消费的作用与构建原则、人与自然的辩证统一关系的论述,对发展低碳经济、构建低碳消费模式具有重要的启示.%At present, low-carbon consumption has become the focus of the domestic academic research problems, but there is little to the low-carbon consumption patterns. The author thinks: low-carbon consumption pattern refers to the consumers' low carbon consumption behavior and standard comprehensive performance based on the requirements of low carbon economy; it generally reflects the people's low carbon consumption behavior of the main content, basic trend and the stipulation of quality. It is to guide people to make low carbon consumption activities, and to generalize the theory of people's social value judgment. The Marxism consumption theory and naturalism constitute the Marxism theoretical foundation of low-carbon consumption patterns. Marxism discusses on the role of the consumer and the construction principle, person and nature the dialectical unity relationship, has the important enlightenment to the development of low carbon economy and building low-carbon consumption pattern.

  12. Connectivity of communication networks

    CERN Document Server

    Mao, Guoqiang

    2017-01-01

    This book introduces a number of recent developments on connectivity of communication networks, ranging from connectivity of large static networks and connectivity of highly dynamic networks to connectivity of small to medium sized networks. This book also introduces some applications of connectivity studies in network optimization, in network localization, and in estimating distances between nodes. The book starts with an overview of the fundamental concepts, models, tools, and methodologies used for connectivity studies. The rest of the chapters are divided into four parts: connectivity of large static networks, connectivity of highly dynamic networks, connectivity of small to medium sized networks, and applications of connectivity studies.

  13. The Intermodulation Lockin Analyzer

    CERN Document Server

    Tholen, Erik A; Forchheimer, Daniel; Schuler, Vivien; Tholen, Mats O; Hutter, Carsten; Haviland, David B

    2011-01-01

    Nonlinear systems can be probed by driving them with two or more pure tones while measuring the intermodulation products of the drive tones in the response. We describe a digital lock-in analyzer which is designed explicitly for this purpose. The analyzer is implemented on a field-programmable gate array, providing speed in analysis, real-time feedback and stability in operation. The use of the analyzer is demonstrated for Intermodulation Atomic Force Microscopy. A generalization of the intermodulation spectral technique to arbitrary drive waveforms is discussed.

  14. Analog multivariate counting analyzers

    CERN Document Server

    Nikitin, A V; Armstrong, T P

    2003-01-01

    Characterizing rates of occurrence of various features of a signal is of great importance in numerous types of physical measurements. Such signal features can be defined as certain discrete coincidence events, e.g. crossings of a signal with a given threshold, or occurrence of extrema of a certain amplitude. We describe measuring rates of such events by means of analog multivariate counting analyzers. Given a continuous scalar or multicomponent (vector) input signal, an analog counting analyzer outputs a continuous signal with the instantaneous magnitude equal to the rate of occurrence of certain coincidence events. The analog nature of the proposed analyzers allows us to reformulate many problems of the traditional counting measurements, and cast them in a form which is readily addressed by methods of differential calculus rather than by algebraic or logical means of digital signal processing. Analog counting analyzers can be easily implemented in discrete or integrated electronic circuits, do not suffer fro...

  15. Analyzing binding data.

    Science.gov (United States)

    Motulsky, Harvey J; Neubig, Richard R

    2010-07-01

    Measuring the rate and extent of radioligand binding provides information on the number of binding sites, and their affinity and accessibility of these binding sites for various drugs. This unit explains how to design and analyze such experiments.

  16. Analyzing in the Present

    DEFF Research Database (Denmark)

    Revsbæk, Line; Pedersen, Lene Tanggaard

    2015-01-01

    The article presents a notion of “analyzing in the present” as a source of inspiration in analyzing qualitative research materials. The term emerged from extensive listening to interview recordings during everyday commuting to university campus. Paying attention to the way different parts...... of various interviews conveyed diverse significance to the listening researcher at different times became a method of continuously opening up the empirical material in a reflexive, breakdown-oriented process of analysis. We argue that situating analysis in the present of analyzing emphasizes and acknowledges...... the interdependency between researcher and researched. On this basis, we advocate an explicit “open-state-of mind” listening as a key aspect of analyzing qualitative material, often described only as a matter of reading transcribed empirical materials, reading theory, and writing. The article contributes...

  17. Miniature mass analyzer

    CERN Document Server

    Cuna, C; Lupsa, N; Cuna, S; Tuzson, B

    2003-01-01

    The paper presents the concept of different mass analyzers that were specifically designed as small dimension instruments able to detect with great sensitivity and accuracy the main environmental pollutants. The mass spectrometers are very suited instrument for chemical and isotopic analysis, needed in environmental surveillance. Usually, this is done by sampling the soil, air or water followed by laboratory analysis. To avoid drawbacks caused by sample alteration during the sampling process and transport, the 'in situ' analysis is preferred. Theoretically, any type of mass analyzer can be miniaturized, but some are more appropriate than others. Quadrupole mass filter and trap, magnetic sector, time-of-flight and ion cyclotron mass analyzers can be successfully shrunk, for each of them some performances being sacrificed but we must know which parameters are necessary to be kept unchanged. To satisfy the miniaturization criteria of the analyzer, it is necessary to use asymmetrical geometries, with ion beam obl...

  18. Analyzing Microarray Data.

    Science.gov (United States)

    Hung, Jui-Hung; Weng, Zhiping

    2017-03-01

    Because there is no widely used software for analyzing RNA-seq data that has a graphical user interface, this protocol provides an example of analyzing microarray data using Babelomics. This analysis entails performing quantile normalization and then detecting differentially expressed genes associated with the transgenesis of a human oncogene c-Myc in mice. Finally, hierarchical clustering is performed on the differentially expressed genes using the Cluster program, and the results are visualized using TreeView.

  19. Connection Strings Property on ADO Connection Object

    Institute of Scientific and Technical Information of China (English)

    Girigi Deogratias; Wu Min; Cao Weihua

    2002-01-01

    The connection string property on ADO connection object contains the information used to establish a connection to the data source. The syntax, the keyword of that information must be in specific format. Depending on the type of data you are connecting to, you need either specify an OLEDB provider or use on ODBC driver. The biggest problem, the industries face is the proliferation of data access interfaces, and the complexity of creating,maintaining and programming against them, and the network problem when communicating over the Intranet or the Internet. This paper first provides an in-depth look of the standard arguments supported by ADO connection string; then gives the easier way for understanding the meaning, the utility and the syntax of the connection strings property on ADO connection object, and finally proposes solution to work around the problems due to the connection strings errors.

  20. Characterizing Variability of Modular Brain Connectivity with Constrained Principal Component Analysis

    Science.gov (United States)

    Hirayama, Jun-ichiro; Hyvärinen, Aapo; Kiviniemi, Vesa; Kawanabe, Motoaki; Yamashita, Okito

    2016-01-01

    Characterizing the variability of resting-state functional brain connectivity across subjects and/or over time has recently attracted much attention. Principal component analysis (PCA) serves as a fundamental statistical technique for such analyses. However, performing PCA on high-dimensional connectivity matrices yields complicated “eigenconnectivity” patterns, for which systematic interpretation is a challenging issue. Here, we overcome this issue with a novel constrained PCA method for connectivity matrices by extending the idea of the previously proposed orthogonal connectivity factorization method. Our new method, modular connectivity factorization (MCF), explicitly introduces the modularity of brain networks as a parametric constraint on eigenconnectivity matrices. In particular, MCF analyzes the variability in both intra- and inter-module connectivities, simultaneously finding network modules in a principled, data-driven manner. The parametric constraint provides a compact module-based visualization scheme with which the result can be intuitively interpreted. We develop an optimization algorithm to solve the constrained PCA problem and validate our method in simulation studies and with a resting-state functional connectivity MRI dataset of 986 subjects. The results show that the proposed MCF method successfully reveals the underlying modular eigenconnectivity patterns in more general situations and is a promising alternative to existing methods. PMID:28002474

  1. Attribute-space connectivity and connected filters

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.

    2007-01-01

    In this paper connected operators from mathematical morphology are extended to a wider class of operators, which are based on connectivities in higher dimensional spaces, similar to scale spaces, which will be called attribute-spaces. Though some properties of connected filters are lost, granulometr

  2. Total organic carbon analyzer

    Science.gov (United States)

    Godec, Richard G.; Kosenka, Paul P.; Smith, Brian D.; Hutte, Richard S.; Webb, Johanna V.; Sauer, Richard L.

    The development and testing of a breadboard version of a highly sensitive total-organic-carbon (TOC) analyzer are reported. Attention is given to the system components including the CO2 sensor, oxidation reactor, acidification module, and the sample-inlet system. Research is reported for an experimental reagentless oxidation reactor, and good results are reported for linearity, sensitivity, and selectivity in the CO2 sensor. The TOC analyzer is developed with gravity-independent components and is designed for minimal additions of chemical reagents. The reagentless oxidation reactor is based on electrolysis and UV photolysis and is shown to be potentially useful. The stability of the breadboard instrument is shown to be good on a day-to-day basis, and the analyzer is capable of 5 sample analyses per day for a period of about 80 days. The instrument can provide accurate TOC and TIC measurements over a concentration range of 20 ppb to 50 ppm C.

  3. Recovery of directed intracortical connectivity from fMRI data

    Science.gov (United States)

    Gilson, Matthieu; Ritter, Petra; Deco, Gustavo

    2016-06-01

    The brain exhibits complex spatio-temporal patterns of activity. In particular, its baseline activity at rest has a specific structure: imaging techniques (e.g., fMRI, EEG and MEG) show that cortical areas experience correlated fluctuations, which is referred to as functional connectivity (FC). The present study relies on our recently developed model in which intracortical white-matter connections shape noise-driven fluctuations to reproduce FC observed in experimental data (here fMRI BOLD signal). Here noise has a functional role and represents the variability of neural activity. The model also incorporates anatomical information obtained using diffusion tensor imaging (DTI), which estimates the density of white-matter fibers (structural connectivity, SC). After optimization to match empirical FC, the model provides an estimation of the efficacies of these fibers, which we call effective connectivity (EC). EC differs from SC, as EC not only accounts for the density of neural fibers, but also the concentration of synapses formed at their end, the type of neurotransmitters associated and the excitability of target neural populations. In summary, the model combines anatomical SC and activity FC to evaluate what drives the neural dynamics, embodied in EC. EC can then be analyzed using graph theory to understand how it generates FC and to seek for functional communities among cortical areas (parcellation of 68 areas). We find that intracortical connections are not symmetric, which affects the dynamic range of cortical activity (i.e., variety of states it can exhibit).

  4. Advances in hematology analyzers.

    Science.gov (United States)

    DeNicola, Dennis B

    2011-05-01

    The complete blood count is one of the basic building blocks of the minimum database in veterinary medicine. Over the past 20 years, there has been a tremendous advancement in the technology of hematology analyzers and their availability to the general practitioner. There are 4 basic methodologies that can be used to generate data for a complete blood count: manual methods, quantitative buffy coat analysis, automated impedance analysis, and flow cytometric analysis. This article will review the principles of these methodologies, discuss some of their advantages and disadvantages, and describe some of the hematology analyzers that are available for the in-house veterinary laboratory.

  5. Analyzing radioligand binding data.

    Science.gov (United States)

    Motulsky, Harvey; Neubig, Richard

    2002-08-01

    Radioligand binding experiments are easy to perform, and provide useful data in many fields. They can be used to study receptor regulation, discover new drugs by screening for compounds that compete with high affinity for radioligand binding to a particular receptor, investigate receptor localization in different organs or regions using autoradiography, categorize receptor subtypes, and probe mechanisms of receptor signaling, via measurements of agonist binding and its regulation by ions, nucleotides, and other allosteric modulators. This unit reviews the theory of receptor binding and explains how to analyze experimental data. Since binding data are usually best analyzed using nonlinear regression, this unit also explains the principles of curve fitting with nonlinear regression.

  6. Portable Fuel Quality Analyzer

    Science.gov (United States)

    2014-01-27

    other transportation industries, such as trucking. The PFQA could also be used in fuel blending operations performed at petroleum, ethanol and biodiesel plants. ...JAN 2014 2. REPORT TYPE Project Summary 3. DATES COVERED 29-07-2013 to 27-01-2014 4. TITLE AND SUBTITLE PORTABLE FUEL QUALITY ANALYZER

  7. Analyzing Workforce Education. Monograph.

    Science.gov (United States)

    Texas Community & Technical Coll. Workforce Education Consortium.

    This monograph examines the issue of task analysis as used in workplace literacy programs, debating the need for it and how to perform it in a rapidly changing environment. Based on experiences of community colleges in Texas, the report analyzes ways that task analysis can be done and how to implement work force education programs more quickly.…

  8. Analyzing Stereotypes in Media.

    Science.gov (United States)

    Baker, Jackie

    1996-01-01

    A high school film teacher studied how students recognized messages in film, examining how film education could help students identify and analyze racial and gender stereotypes. Comparison of students' attitudes before and after the film course found that the course was successful in raising students' consciousness. (SM)

  9. Undifferentiated Connective Tissue Disease

    Science.gov (United States)

    ... Home Conditions Undifferentiated Connective Tissue Disease (UCTD) Undifferentiated Connective Tissue Disease (UCTD) Make an Appointment Find a Doctor ... L. Goldstein, MD, MMSc (February 01, 2016) Undifferentiated connective tissue disease (UCTD) is a systemic autoimmune disease. This ...

  10. Connective Tissue Disorders

    Science.gov (United States)

    Connective tissue is the material inside your body that supports many of its parts. It is the "cellular ... their work. Cartilage and fat are examples of connective tissue. There are over 200 disorders that impact connective ...

  11. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    . We use three axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well as all...... connection costs; and, (3) the central planner selects a cost minimizing network satisfying reported connection demands based on estimated connection costs and allocates true connection costs of the selected network....

  12. Magnetoresistive emulsion analyzer.

    Science.gov (United States)

    Lin, Gungun; Baraban, Larysa; Han, Luyang; Karnaushenko, Daniil; Makarov, Denys; Cuniberti, Gianaurelio; Schmidt, Oliver G

    2013-01-01

    We realize a magnetoresistive emulsion analyzer capable of detection, multiparametric analysis and sorting of ferrofluid-containing nanoliter-droplets. The operation of the device in a cytometric mode provides high throughput and quantitative information about the dimensions and magnetic content of the emulsion. Our method offers important complementarity to conventional optical approaches involving ferrofluids, and paves the way to the development of novel compact tools for diagnostics and nanomedicine including drug design and screening.

  13. PhosphoSiteAnalyzer

    DEFF Research Database (Denmark)

    Bennetzen, Martin V; Cox, Jürgen; Mann, Matthias

    2012-01-01

    an algorithm to retrieve kinase predictions from the public NetworKIN webpage in a semiautomated way and applies hereafter advanced statistics to facilitate a user-tailored in-depth analysis of the phosphoproteomic data sets. The interface of the software provides a high degree of analytical flexibility...... and is designed to be intuitive for most users. PhosphoSiteAnalyzer is a freeware program available at http://phosphosite.sourceforge.net ....

  14. IPv6 Protocol Analyzer

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With the emerging of next generation Intemet protocol (IPv6), it is expected to replace the current version of Internet protocol (IPv4) that will be exhausted in the near future. Besides providing adequate address space, some other new features are included into the new 128 bits of IP such as IP auto configuration, quality of service, simple routing capability, security, mobility and multicasting. The current protocol analyzer will not be able to handle IPv6 packets. This paper will focus on developing protocol analyzer that decodes IPv6 packet. IPv6 protocol analyzer is an application module,which is able to decode the IPv6 packet and provide detail breakdown of the construction of the packet. It has to understand the detail construction of the IPv6, and provide a high level abstraction of bits and bytes of the IPv6 packet.Thus it increases network administrators' understanding of a network protocol,helps he/she in solving protocol related problem in a IPv6 network environment.

  15. Analyzing EUV mask costs

    Science.gov (United States)

    Lercel, Michael; Kasprowicz, Bryan

    2016-10-01

    The introduction of Extreme Ultraviolet Lithography (EUV) as a replacement for multiple patterning is based on improvements of cycle time, yield, and cost. Earlier cost studies have assumed a simple assumption that EUV masks (being more complex with the multilayer coated blank) are not more than three times as expensive as advanced ArFi (ArF immersion) masks. EUV masks are expected to be more expensive during the ramp of the technology because of the added cost of the complex mask blank, the use of EUV specific mask tools, and a ramp of yield learning relative to the more mature technologies. This study concludes that, within a range of scenarios, the hypothesis that EUV mask costs are not more than three times that of advanced ArFi masks is valid and conservative.

  16. Analyzing Chinese Financial Reporting

    Institute of Scientific and Technical Information of China (English)

    SABRINA; ZHANG

    2008-01-01

    If the world’s capital markets could use a harmonized accounting framework it would not be necessary for a comparison between two or more sets of accounting standards. However,there is much to do before this becomes reality.This article aims to pres- ent a general overview of China’s General Accepted Accounting Principles(GAAP), U.S.General Accepted Accounting Principles and International Financial Reporting Standards(IFRS),and to analyze the differ- ences among IFRS,U.S.GAAP and China GAAP using fixed assets as an example.

  17. Analyzing business models

    DEFF Research Database (Denmark)

    Nielsen, Christian

    2014-01-01

    financial statement. Plumlee (2003) finds for instance that such information imposes significant costs on even expert users such as analysts and fund managers and reduces their use of it. Analysts’ ability to incorporate complex information in their analyses is a decreasing function of its complexity......, because the costs of processing and analyzing it exceed the benefits indicating bounded rationality. Hutton (2002) concludes that the analyst community’s inability to raise important questions on quality of management and the viability of its business model inevitably led to the Enron debacle. There seems...

  18. Mineral/Water Analyzer

    Science.gov (United States)

    1983-01-01

    An x-ray fluorescence spectrometer developed for the Viking Landers by Martin Marietta was modified for geological exploration, water quality monitoring, and aircraft engine maintenance. The aerospace system was highly miniaturized and used very little power. It irradiates the sample causing it to emit x-rays at various energies, then measures the energy levels for sample composition analysis. It was used in oceanographic applications and modified to identify element concentrations in ore samples, on site. The instrument can also analyze the chemical content of water, and detect the sudden development of excessive engine wear.

  19. Analyzing Aeroelasticity in Turbomachines

    Science.gov (United States)

    Reddy, T. S. R.; Srivastava, R.

    2003-01-01

    ASTROP2-LE is a computer program that predicts flutter and forced responses of blades, vanes, and other components of such turbomachines as fans, compressors, and turbines. ASTROP2-LE is based on the ASTROP2 program, developed previously for analysis of stability of turbomachinery components. In developing ASTROP2- LE, ASTROP2 was modified to include a capability for modeling forced responses. The program was also modified to add a capability for analysis of aeroelasticity with mistuning and unsteady aerodynamic solutions from another program, LINFLX2D, that solves the linearized Euler equations of unsteady two-dimensional flow. Using LINFLX2D to calculate unsteady aerodynamic loads, it is possible to analyze effects of transonic flow on flutter and forced response. ASTROP2-LE can be used to analyze subsonic, transonic, and supersonic aerodynamics and structural mistuning for rotors with blades of differing structural properties. It calculates the aerodynamic damping of a blade system operating in airflow so that stability can be assessed. The code also predicts the magnitudes and frequencies of the unsteady aerodynamic forces on the airfoils of a blade row from incoming wakes. This information can be used in high-cycle fatigue analysis to predict the fatigue lives of the blades.

  20. Field Deployable DNA analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, E; Christian, A; Marion, J; Sorensen, K; Arroyo, E; Vrankovich, G; Hara, C; Nguyen, C

    2005-02-09

    This report details the feasibility of a field deployable DNA analyzer. Steps for swabbing cells from surfaces and extracting DNA in an automatable way are presented. Since enzymatic amplification reactions are highly sensitive to environmental contamination, sample preparation is a crucial step to make an autonomous deployable instrument. We perform sample clean up and concentration in a flow through packed bed. For small initial samples, whole genome amplification is performed in the packed bed resulting in enough product for subsequent PCR amplification. In addition to DNA, which can be used to identify a subject, protein is also left behind, the analysis of which can be used to determine exposure to certain substances, such as radionuclides. Our preparative step for DNA analysis left behind the protein complement as a waste stream; we determined to learn if the proteins themselves could be analyzed in a fieldable device. We successfully developed a two-step lateral flow assay for protein analysis and demonstrate a proof of principle assay.

  1. Analyzing the platelet proteome.

    Science.gov (United States)

    García, Angel; Zitzmann, Nicole; Watson, Steve P

    2004-08-01

    During the last 10 years, mass spectrometry (MS) has become a key tool for protein analysis and has underpinned the emerging field of proteomics. Using high-throughput tandem MS/MS following protein separation, it is potentially possible to analyze hundreds to thousands of proteins in a sample at a time. This technology can be used to analyze the protein content (i.e., the proteome) of any cell or tissue and complements the powerful field of genomics. The technology is particularly suitable for platelets because of the absence of a nucleus. Cellular proteins can be separated by either gel-based methods such as two-dimensional gel electrophoresis or one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by liquid chromatography (LC) -MS/MS or by multidimensional LC-MS/MS. Prefractionation techniques, such as subcellular fractionations or immunoprecipitations, can be used to improve the analysis. Each method has particular advantages and disadvantages. Proteomics can be used to compare the proteome of basal and diseased platelets, helping to reveal information on the molecular basis of the disease.

  2. Analyzing Agricultural Agglomeration in China

    Directory of Open Access Journals (Sweden)

    Erling Li

    2017-02-01

    Full Text Available There has been little scholarly research on Chinese agriculture’s geographic pattern of agglomeration and its evolutionary mechanisms, which are essential to sustainable development in China. By calculating the barycenter coordinates, the Gini coefficient, spatial autocorrelation and specialization indices for 11 crops during 1981–2012, we analyze the evolutionary pattern and mechanisms of agricultural agglomeration. We argue that the degree of spatial concentration of Chinese planting has been gradually increasing and that regional specialization and diversification have progressively been strengthened. Furthermore, Chinese crop production is moving from the eastern provinces to the central and western provinces. This is in contrast to Chinese manufacturing growth which has continued to be concentrated in the coastal and southeastern regions. In Northeast China, the Sanjiang and Songnen plains have become agricultural clustering regions, and the earlier domination of aquaculture and rice production in Southeast China has gradually decreased. In summary, this paper provides a political economy framework for understanding the regionalization of Chinese agriculture, focusing on the interaction among the objectives, decisionmaking behavior, path dependencies and spatial effects.

  3. Analyzing architecture articles

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In the present study, we express the quality, function, and characteristics of architecture to help people comprehensively understand what architecture is. We also reveal the problems and conflict found in population, land, water resources, pollution, energy, and the organization systems in construction. China’s economy is transforming. We should focus on the cities, architectural environment, energy conservation, emission-reduction, and low-carbon output that will result in successful green development. We should macroscopically and microscopically analyze the development, from the natural environment to the artificial environment; from the relationship between human beings and nature to the combination of social ecology in cities, and farmlands. We must learn to develop and control them harmoniously and scientifically to provide a foundation for the methods used in architecture research.

  4. Analyzing geographic clustered response

    Energy Technology Data Exchange (ETDEWEB)

    Merrill, D.W.; Selvin, S.; Mohr, M.S.

    1991-08-01

    In the study of geographic disease clusters, an alternative to traditional methods based on rates is to analyze case locations on a transformed map in which population density is everywhere equal. Although the analyst's task is thereby simplified, the specification of the density equalizing map projection (DEMP) itself is not simple and continues to be the subject of considerable research. Here a new DEMP algorithm is described, which avoids some of the difficulties of earlier approaches. The new algorithm (a) avoids illegal overlapping of transformed polygons; (b) finds the unique solution that minimizes map distortion; (c) provides constant magnification over each map polygon; (d) defines a continuous transformation over the entire map domain; (e) defines an inverse transformation; (f) can accept optional constraints such as fixed boundaries; and (g) can use commercially supported minimization software. Work is continuing to improve computing efficiency and improve the algorithm. 21 refs., 15 figs., 2 tabs.

  5. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  6. Science and Mathematics--A Natural Connection

    Science.gov (United States)

    Park Rogers, Meredith A.; Volkmann, Mark J.; Abell, Sandra K.

    2007-01-01

    Connections between science and mathematics seem natural. First, mathematics can be used in science to organize and analyze data in tables and graphs. Second, mathematics can help represent scientific phenomena and understand scientific concepts. Student learning should benefit when teachers make the connections between science and mathematics…

  7. TEAMS Model Analyzer

    Science.gov (United States)

    Tijidjian, Raffi P.

    2010-01-01

    The TEAMS model analyzer is a supporting tool developed to work with models created with TEAMS (Testability, Engineering, and Maintenance System), which was developed by QSI. In an effort to reduce the time spent in the manual process that each TEAMS modeler must perform in the preparation of reporting for model reviews, a new tool has been developed as an aid to models developed in TEAMS. The software allows for the viewing, reporting, and checking of TEAMS models that are checked into the TEAMS model database. The software allows the user to selectively model in a hierarchical tree outline view that displays the components, failure modes, and ports. The reporting features allow the user to quickly gather statistics about the model, and generate an input/output report pertaining to all of the components. Rules can be automatically validated against the model, with a report generated containing resulting inconsistencies. In addition to reducing manual effort, this software also provides an automated process framework for the Verification and Validation (V&V) effort that will follow development of these models. The aid of such an automated tool would have a significant impact on the V&V process.

  8. Analyzing Spacecraft Telecommunication Systems

    Science.gov (United States)

    Kordon, Mark; Hanks, David; Gladden, Roy; Wood, Eric

    2004-01-01

    Multi-Mission Telecom Analysis Tool (MMTAT) is a C-language computer program for analyzing proposed spacecraft telecommunication systems. MMTAT utilizes parameterized input and computational models that can be run on standard desktop computers to perform fast and accurate analyses of telecommunication links. MMTAT is easy to use and can easily be integrated with other software applications and run as part of almost any computational simulation. It is distributed as either a stand-alone application program with a graphical user interface or a linkable library with a well-defined set of application programming interface (API) calls. As a stand-alone program, MMTAT provides both textual and graphical output. The graphs make it possible to understand, quickly and easily, how telecommunication performance varies with variations in input parameters. A delimited text file that can be read by any spreadsheet program is generated at the end of each run. The API in the linkable-library form of MMTAT enables the user to control simulation software and to change parameters during a simulation run. Results can be retrieved either at the end of a run or by use of a function call at any time step.

  9. Bios data analyzer.

    Science.gov (United States)

    Sabelli, H; Sugerman, A; Kovacevic, L; Kauffman, L; Carlson-Sabelli, L; Patel, M; Konecki, J

    2005-10-01

    The Bios Data Analyzer (BDA) is a set of computer programs (CD-ROM, in Sabelli et al., Bios. A Study of Creation, 2005) for new time series analyses that detects and measures creative phenomena, namely diversification, novelty, complexes, nonrandom complexity. We define a process as creative when its time series displays these properties. They are found in heartbeat interval series, the exemplar of bios .just as turbulence is the exemplar of chaos, in many other empirical series (galactic distributions, meteorological, economic and physiological series), in biotic series generated mathematically by the bipolar feedback, and in stochastic noise, but not in chaotic attractors. Differencing, consecutive recurrence and partial autocorrelation indicate nonrandom causation, thereby distinguishing chaos and bios from random and random walk. Embedding plots distinguish causal creative processes (e.g. bios) that include both simple and complex components of variation from stochastic processes (e.g. Brownian noise) that include only complex components, and from chaotic processes that decay from order to randomness as the number of dimensions is increased. Varying bin and dimensionality show that entropy measures symmetry and variety, and that complexity is associated with asymmetry. Trigonometric transformations measure coexisting opposites in time series and demonstrate bipolar, partial, and uncorrelated opposites in empirical processes and bios, supporting the hypothesis that bios is generated by bipolar feedback, a concept which is at variance with standard concepts of polar and complementary opposites.

  10. Non-homogenous neural networks with chaotic recursive nodes: connectivity and multi-assemblies structures in recursive processing elements architectures.

    Science.gov (United States)

    Del Moral Hernandez, Emilio

    2005-01-01

    This paper addresses recurrent neural architectures based on bifurcating nodes that exhibit chaotic dynamics, with local dynamics defined by first order parametric recursions. In the studied architectures, logistic recursive nodes interact through parametric coupling, they self organize, and the network evolves to global spatio-temporal period-2 attractors that encode stored patterns. The performance of associative memories arrangements is measured through the average error in pattern recovery, under several levels of prompting noise. The impact of the synaptic connections magnitude on architecture performance is analyzed in detail, through pattern recovery performance measures and basin of attraction characterization. The importance of a planned choice of the synaptic connections scale in RPEs architectures is shown. A strategy for minimizing pattern recovery degradation when the number of stored patterns increases is developed. Experimental results show the success of such strategy. Mechanisms for allowing the studied associative networks to deal with asynchronous changes in input patterns, and tools for the interconnection between different associative assemblies are developed. Finally, coupling in heterogeneous assemblies with diverse recursive maps is analyzed, and the associated synaptic connections are equated.

  11. Digital Microfluidics Sample Analyzer

    Science.gov (United States)

    Pollack, Michael G.; Srinivasan, Vijay; Eckhardt, Allen; Paik, Philip Y.; Sudarsan, Arjun; Shenderov, Alex; Hua, Zhishan; Pamula, Vamsee K.

    2010-01-01

    Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations. A chip is incorporated into the system with a controller, a detector, input and output devices, and software. A novel filler fluid formulation is used for the transport of droplets with high protein concentrations. Novel assemblies for detection of photons from an on-chip droplet are present, as well as novel systems for conducting various assays, such as immunoassays and PCR (polymerase chain reaction). The lab-on-a-chip (a.k.a., lab-on-a-printed-circuit board) processes physiological samples and comprises a system for automated, multi-analyte measurements using sub-microliter samples of human serum. The invention also relates to a diagnostic chip and system including the chip that performs many of the routine operations of a central labbased chemistry analyzer, integrating, for example, colorimetric assays (e.g., for proteins), chemiluminescence/fluorescence assays (e.g., for enzymes, electrolytes, and gases), and/or conductometric assays (e.g., for hematocrit on plasma and whole blood) on a single chip platform.

  12. Structural Connectivity of the Developing Human Amygdala

    Science.gov (United States)

    Saygin, Zeynep M.; Osher, David E.; Koldewyn, Kami; Martin, Rebecca E.; Finn, Amy; Saxe, Rebecca; Gabrieli, John D.E.; Sheridan, Margaret

    2015-01-01

    A large corpus of research suggests that there are changes in the manner and degree to which the amygdala supports cognitive and emotional function across development. One possible basis for these developmental differences could be the maturation of amygdalar connections with the rest of the brain. Recent functional connectivity studies support this conclusion, but the structural connectivity of the developing amygdala and its different nuclei remains largely unstudied. We examined age related changes in the DWI connectivity fingerprints of the amygdala to the rest of the brain in 166 individuals of ages 5-30. We also developed a model to predict age based on individual-subject amygdala connectivity, and identified the connections that were most predictive of age. Finally, we segmented the amygdala into its four main nucleus groups, and examined the developmental changes in connectivity for each nucleus. We observed that with age, amygdalar connectivity becomes increasingly sparse and localized. Age related changes were largely localized to the subregions of the amygdala that are implicated in social inference and contextual memory (the basal and lateral nuclei). The central nucleus’ connectivity also showed differences with age but these differences affected fewer target regions than the basal and lateral nuclei. The medial nucleus did not exhibit any age related changes. These findings demonstrate increasing specificity in the connectivity patterns of amygdalar nuclei across age. PMID:25875758

  13. Structural connectivity of the developing human amygdala.

    Directory of Open Access Journals (Sweden)

    Zeynep M Saygin

    Full Text Available A large corpus of research suggests that there are changes in the manner and degree to which the amygdala supports cognitive and emotional function across development. One possible basis for these developmental differences could be the maturation of amygdalar connections with the rest of the brain. Recent functional connectivity studies support this conclusion, but the structural connectivity of the developing amygdala and its different nuclei remains largely unstudied. We examined age related changes in the DWI connectivity fingerprints of the amygdala to the rest of the brain in 166 individuals of ages 5-30. We also developed a model to predict age based on individual-subject amygdala connectivity, and identified the connections that were most predictive of age. Finally, we segmented the amygdala into its four main nucleus groups, and examined the developmental changes in connectivity for each nucleus. We observed that with age, amygdalar connectivity becomes increasingly sparse and localized. Age related changes were largely localized to the subregions of the amygdala that are implicated in social inference and contextual memory (the basal and lateral nuclei. The central nucleus' connectivity also showed differences with age but these differences affected fewer target regions than the basal and lateral nuclei. The medial nucleus did not exhibit any age related changes. These findings demonstrate increasing specificity in the connectivity patterns of amygdalar nuclei across age.

  14. Soft Decision Analyzer

    Science.gov (United States)

    Steele, Glen; Lansdowne, Chatwin; Zucha, Joan; Schlensinger, Adam

    2013-01-01

    The Soft Decision Analyzer (SDA) is an instrument that combines hardware, firmware, and software to perform realtime closed-loop end-to-end statistical analysis of single- or dual- channel serial digital RF communications systems operating in very low signal-to-noise conditions. As an innovation, the unique SDA capabilities allow it to perform analysis of situations where the receiving communication system slips bits due to low signal-to-noise conditions or experiences constellation rotations resulting in channel polarity in versions or channel assignment swaps. SDA s closed-loop detection allows it to instrument a live system and correlate observations with frame, codeword, and packet losses, as well as Quality of Service (QoS) and Quality of Experience (QoE) events. The SDA s abilities are not confined to performing analysis in low signal-to-noise conditions. Its analysis provides in-depth insight of a communication system s receiver performance in a variety of operating conditions. The SDA incorporates two techniques for identifying slips. The first is an examination of content of the received data stream s relation to the transmitted data content and the second is a direct examination of the receiver s recovered clock signals relative to a reference. Both techniques provide benefits in different ways and allow the communication engineer evaluating test results increased confidence and understanding of receiver performance. Direct examination of data contents is performed by two different data techniques, power correlation or a modified Massey correlation, and can be applied to soft decision data widths 1 to 12 bits wide over a correlation depth ranging from 16 to 512 samples. The SDA detects receiver bit slips within a 4 bits window and can handle systems with up to four quadrants (QPSK, SQPSK, and BPSK systems). The SDA continuously monitors correlation results to characterize slips and quadrant change and is capable of performing analysis even when the

  15. Graph Theory and ANT Colony Optimization Approach for Forest Patch Connectivity Analysis

    Science.gov (United States)

    Shantala Devi, B. S.; Murthy, M. S. R.; Pujar, G. S.; Debnath, B.

    2011-08-01

    Forest connectivity is necessary for prioritizing biodiversity conservation. Connectivity indices facilitate to predict the movement pattern of species across complex landscapes. Change in area and inter-patch distance in forest affects the biodiversity, wildlife movement, seed dispersal and other ecological factors. In graph theory components play an important role to analyze the group of patches and its impact with reference to the threshold distance between the patches. The study on link, threshold distance and components showed that with the increase in threshold distance, number of components decreased and number of links increased. Also Integral index of connectivity importance value (dIIC > 0.05) is high for big forest patches and considered to be intact forest. For those less than 0.05 importance value requires protection and conservation. Hence dIIC is categorised into Very low, low, Medium, high and Very high to analyze the degree of connectivity. Choosing correct threshold distance based on the requirement of species movement is preferred. Based on the selection of potential habitat patches shortest path between them is determined using Ant Colony Optimization (ACO) Technique. Vegetation type Map, Slope, Elevation, Disturbance Index, Biological Richness Map and DIIC layers facilitated to analyze the optimal path of the species through ACO for connectivity. Graph Theory and ACO works as a robust tool for Biodiversity Conservation.

  16. Structured patterns retrieval using a metric attractor network: Application to fingerprint recognition

    Science.gov (United States)

    Doria, Felipe; Erichsen, Rubem; González, Mario; Rodríguez, Francisco B.; Sánchez, Ángel; Dominguez, David

    2016-09-01

    The ability of a metric attractor neural networks (MANN) to learn structured patterns is analyzed. In particular we consider collections of fingerprints, which present some local features, rather than being modeled by random patterns. The network retrieval proved to be robust to varying the pattern activity, the threshold strategy, the topological arrangement of the connections, and for several types of noisy configuration. We found that the lower the fingerprint patterns activity is, the higher the load ratio and retrieval quality are. A simplified theoretical framework, for the unbiased case, is developed as a function of five parameters: the load ratio, the finiteness connectivity, the density degree of the network, randomness ratio, and the spatial pattern correlation. Linked to the latter appears a new neural dynamics variable: the spatial neural correlation. The theory agrees quite well with the experimental results.

  17. Analyzing neuronal networks using discrete-time dynamics

    Science.gov (United States)

    Ahn, Sungwoo; Smith, Brian H.; Borisyuk, Alla; Terman, David

    2010-05-01

    We develop mathematical techniques for analyzing detailed Hodgkin-Huxley like models for excitatory-inhibitory neuronal networks. Our strategy for studying a given network is to first reduce it to a discrete-time dynamical system. The discrete model is considerably easier to analyze, both mathematically and computationally, and parameters in the discrete model correspond directly to parameters in the original system of differential equations. While these networks arise in many important applications, a primary focus of this paper is to better understand mechanisms that underlie temporally dynamic responses in early processing of olfactory sensory information. The models presented here exhibit several properties that have been described for olfactory codes in an insect’s Antennal Lobe. These include transient patterns of synchronization and decorrelation of sensory inputs. By reducing the model to a discrete system, we are able to systematically study how properties of the dynamics, including the complex structure of the transients and attractors, depend on factors related to connectivity and the intrinsic and synaptic properties of cells within the network.

  18. Evolution of Plastic Learning in Spiking Networks via Memristive Connections

    OpenAIRE

    Howard, Gerard; Gale, Ella; Bull, Larry; Costello, Ben de Lacy; Adamatzky, Andy

    2012-01-01

    This article presents a spiking neuroevolutionary system which implements memristors as plastic connections, i.e. whose weights can vary during a trial. The evolutionary design process exploits parameter self-adaptation and variable topologies, allowing the number of neurons, connection weights, and inter-neural connectivity pattern to emerge. By comparing two phenomenological real-world memristor implementations with networks comprised of (i) linear resistors (ii) constant-valued connections...

  19. Analyzing and modeling heterogeneous behavior

    Science.gov (United States)

    Lin, Zhiting; Wu, Xiaoqing; He, Dongyue; Zhu, Qiang; Ni, Jixiang

    2016-05-01

    Recently, it was pointed out that the non-Poisson statistics with heavy tail existed in many scenarios of human behaviors. But most of these studies claimed that power-law characterized diverse aspects of human mobility patterns. In this paper, we suggest that human behavior may not be driven by identical mechanisms and can be modeled as a Semi-Markov Modulated Process. To verify our suggestion and model, we analyzed a total of 1,619,934 records of library visitations (including undergraduate and graduate students). It is found that the distribution of visitation intervals is well fitted with three sections of lines instead of the traditional power law distribution in log-log scale. The results confirm that some human behaviors cannot be simply expressed as power law or any other simple functions. At the same time, we divided the data into groups and extracted period bursty events. Through careful analysis in different groups, we drew a conclusion that aggregate behavior might be composed of heterogeneous behaviors, and even the behaviors of the same type tended to be different in different period. The aggregate behavior is supposed to be formed by "heterogeneous groups". We performed a series of experiments. Simulation results showed that we just needed to set up two states Semi-Markov Modulated Process to construct proper representation of heterogeneous behavior.

  20. Asymptotically hyperbolic connections

    CERN Document Server

    Fine, Joel; Krasnov, Kirill; Scarinci, Carlos

    2015-01-01

    General Relativity in 4 dimensions can be equivalently described as a dynamical theory of SO(3)-connections rather than metrics. We introduce the notion of asymptotically hyperbolic connections, and work out an analog of the Fefferman-Graham expansion in the language of connections. As in the metric setup, one can solve the arising "evolution" equations order by order in the expansion in powers of the radial coordinate. The solution in the connection setting is arguably simpler, and very straightforward algebraic manipulations allow one to see how the obstruction appears at third order in the expansion. Another interesting feature of the connection formulation is that the "counter terms" required in the computation of the renormalised volume all combine into the Chern-Simons functional of the restriction of the connection to the boundary. As the Chern-Simons invariant is only defined modulo large gauge transformations, the requirement that the path integral over asymptotically hyperbolic connections is well-d...

  1. Electrophysiological and functional connectivity of the human supplementary motor area.

    Science.gov (United States)

    Narayana, Shalini; Laird, Angela R; Tandon, Nitin; Franklin, Crystal; Lancaster, Jack L; Fox, Peter T

    2012-08-01

    Neuro-imaging methods for detecting functional and structural inter-regional connectivity are in a rapid phase of development. While reports of regional connectivity patterns based on individual methods are becoming common, studies comparing the results of two or more connectivity-mapping methods remain rare. In this study, we applied transcranial magnetic stimulation during PET imaging (TMS/PET), a stimulation-based method, and meta-analytic connectivity modeling (MACM), a task-based method to map the connectivity patterns of the supplementary motor area (SMA). Further, we drew upon the behavioral domain meta-data of the BrainMap® database to characterize the behavioral domain specificity of two maps. Both MACM and TMS/PET detected multi-synaptic connectivity patterns, with the MACM-detected connections being more extensive. Both MACM and TMS/PET detected connections belonging to multiple behavioral domains, including action, cognition and perception. Finally, we show that the two connectivity-mapping methods are complementary in that, the MACM informed on the functional nature of SMA connections, while TMS/PET identified brain areas electrophysiologically connected with the SMA. Thus, we demonstrate that integrating multimodal database and imaging techniques can derive comprehensive connectivity maps of brain areas.

  2. Abnormal synchrony and effective connectivity in patients with schizophrenia and auditory hallucinations

    Science.gov (United States)

    de la Iglesia-Vaya, Maria; Escartí, Maria José; Molina-Mateo, Jose; Martí-Bonmatí, Luis; Gadea, Marien; Castellanos, Francisco Xavier; Aguilar García-Iturrospe, Eduardo J.; Robles, Montserrat; Biswal, Bharat B.; Sanjuan, Julio

    2014-01-01

    Auditory hallucinations (AH) are the most frequent positive symptoms in patients with schizophrenia. Hallucinations have been related to emotional processing disturbances, altered functional connectivity and effective connectivity deficits. Previously, we observed that, compared to healthy controls, the limbic network responses of patients with auditory hallucinations differed when the subjects were listening to emotionally charged words. We aimed to compare the synchrony patterns and effective connectivity of task-related networks between schizophrenia patients with and without AH and healthy controls. Schizophrenia patients with AH (n = 27) and without AH (n = 14) were compared with healthy participants (n = 31). We examined functional connectivity by analyzing correlations and cross-correlations among previously detected independent component analysis time courses. Granger causality was used to infer the information flow direction in the brain regions. The results demonstrate that the patterns of cortico-cortical functional synchrony differentiated the patients with AH from the patients without AH and from the healthy participants. Additionally, Granger-causal relationships between the networks clearly differentiated the groups. In the patients with AH, the principal causal source was an occipital–cerebellar component, versus a temporal component in the patients without AH and the healthy controls. These data indicate that an anomalous process of neural connectivity exists when patients with AH process emotional auditory stimuli. Additionally, a central role is suggested for the cerebellum in processing emotional stimuli in patients with persistent AH. PMID:25379429

  3. A resource-efficient adaptive Fourier analyzer

    Science.gov (United States)

    Hajdu, C. F.; Zamantzas, C.; Dabóczi, T.

    2016-10-01

    We present a resource-efficient frequency adaptation method to complement the Fourier analyzer proposed by Péceli. The novel frequency adaptation scheme is based on the adaptive Fourier analyzer suggested by Nagy. The frequency adaptation method was elaborated with a view to realizing a detector connectivity check on an FPGA in a new beam loss monitoring (BLM) system, currently being developed for beam setup and machine protection of the particle accelerators at the European Organisation for Nuclear Research (CERN). The paper summarizes the Fourier analyzer to the extent relevant to this work and the basic principle of the related frequency adaptation methods. It then outlines the suggested new scheme, presents practical considerations for implementing it and underpins it with an example and the corresponding operational experience.

  4. ANALYSIS OF THE CONNECTION BETWEEN URBAN LAND COVER AND CENSUS DISTRICTS USING GEOINFORMATICAL METHODS

    Directory of Open Access Journals (Sweden)

    Henits László

    2015-12-01

    Full Text Available Remote sensing resources are usually used in research to better understand urban built-up density, spatial structure and the processes of change. Based on results of image segmentation, landscape metrics indexes, texture and pattern may be analyzed beside the spatial changes in urban reflectance. Social processes within the settlement can be analyzed efficiently, although the census data may also be connected to the urban land cover data through geoinformation systems. On the research project different parameters of urban segments, i.e. patch number, mean patch area, total patch area, total patch perimeter, patch density and edge density, formations that make up the urban pattern were analyzed. Urban functional districts of different built-up density were separated using appropriate indexes, and extending the database with spectral content made it possible to review district boundaries and to mark new boundaries due to these changes.

  5. Mathematical Modeling of Column-Base Connections under Monotonic Loading

    Directory of Open Access Journals (Sweden)

    Gholamreza Abdollahzadeh

    2014-12-01

    Full Text Available Some considerable damage to steel structures during the Hyogo-ken Nanbu Earthquake occurred. Among them, many exposed-type column bases failed in several consistent patterns, such as brittle base plate fracture, excessive bolt elongation, unexpected early bolt failure, and inferior construction work, etc. The lessons from these phenomena led to the need for improved understanding of column base behavior. Joint behavior must be modeled when analyzing semi-rigid frames, which is associated with a mathematical model of the moment–rotation curve. The most accurate model uses continuous nonlinear functions. This article presents three areas of steel joint research: (1 analysis methods of semi-rigid joints; (2 prediction methods for the mechanical behavior of joints; (3 mathematical representations of the moment–rotation curve. In the current study, a new exponential model to depict the moment–rotation relationship of column base connection is proposed. The proposed nonlinear model represents an approach to the prediction of M–θ curves, taking into account the possible failure modes and the deformation characteristics of the connection elements. The new model has three physical parameters, along with two curve-fitted factors. These physical parameters are generated from dimensional details of the connection, as well as the material properties. The M–θ curves obtained by the model are compared with published connection tests and 3D FEM research. The proposed mathematical model adequately comes close to characterizing M–θ behavior through the full range of loading/rotations. As a result, modeling of column base connections using the proposed mathematical model can give crucial beforehand information, and overcome the disadvantages of time consuming workmanship and cost of experimental studies.

  6. Global imprint of historical connectivity on freshwater fish biodiversity.

    Science.gov (United States)

    Dias, Murilo S; Oberdorff, Thierry; Hugueny, Bernard; Leprieur, Fabien; Jézéquel, Céline; Cornu, Jean-François; Brosse, Sébastien; Grenouillet, Gael; Tedesco, Pablo A

    2014-09-01

    The relative importance of contemporary and historical processes is central for understanding biodiversity patterns. While several studies show that past conditions can partly explain the current biodiversity patterns, the role of history remains elusive. We reconstructed palaeo-drainage basins under lower sea level conditions (Last Glacial Maximum) to test whether the historical connectivity between basins left an imprint on the global patterns of freshwater fish biodiversity. After controlling for contemporary and past environmental conditions, we found that palaeo-connected basins displayed greater species richness but lower levels of endemism and beta diversity than did palaeo-disconnected basins. Palaeo-connected basins exhibited shallower distance decay of compositional similarity, suggesting that palaeo-river connections favoured the exchange of fish species. Finally, we found that a longer period of palaeo-connection resulted in lower levels of beta diversity. These findings reveal the first unambiguous results of the role played by history in explaining the global contemporary patterns of biodiversity.

  7. Connectivity measures in EEG microstructural sleep elements

    Directory of Open Access Journals (Sweden)

    Dimitris eSakellariou

    2016-02-01

    Full Text Available During Non-Rapid Eye Movement sleep (NREM the brain is relatively disconnected from the environment, while connectedness between brain areas is also decreased. Evidence indicates that these dynamic connectivity changes are delivered by microstructural elements of sleep: short periods of environmental stimuli evaluation followed by sleep promoting procedures. The connectivity patterns of the latter, among other aspects of sleep microstructure, are still to be fully elucidated.We suggest here a methodology for the assessment and investigation of the connectivity patterns of EEG microstructural elements, such as sleep spindles. The methodology combines techniques in the preprocessing, estimation, error assessing and visualization of results levels in order to allow the detailed examination of the connectivity aspects (levels and directionality of information flow over frequency and time with notable resolution, while dealing with the volume conduction and EEG reference assessment. The high temporal and frequency resolution of the methodology will allow the association between the microelements and the dynamically forming networks that characterise them, and consequently possibly reveal aspects of the EEG microstructure. The proposed methodology is initially tested on artificially generated signals for proof of concept and subsequently applied to real EEG recordings via a custom built MATLAB-based tool developed for such studies. Preliminary results from 843 fast sleep spindles recorded in whole night sleep of 5 healthy volunteers indicate a prevailing pattern of interactions between centroparietal and frontal regions.We demonstrate hereby an opening to our knowledge attempt to estimate the scalp EEG connectivity that characterizes fast sleep spindles via an EEG-element connectivity methodology we propose. The application of the latter, via a computational tool we developed suggests it is able to investigate the connectivity patterns related to the

  8. Impact of land use changes on connectivity in a rural catchment with mild topography

    Science.gov (United States)

    Langhammer, Jakub; Ghaffari, Golaleh

    2016-04-01

    Concept of sediment connectivity and quantitative assessment of its spatial distribution became important tool for analysis of spatial connectivity of sediment transport processes in basins. Most of the first connectivity studies is focused on montane basins with high rates of erosion originating in steep slopes in headwater areas. However, less attention is paid to the mild landscapes in highland and lowland landscape, with often high connectivity. It applies to the rural areas where the sediment transport and erosion control are of key importance. Assessment of connectivity and its control in such environment thus can contribute to the efficient and sustainable landscape management. In our study we have tested applicability of the concept of index of sediment connectivity (IC) in mid-latitude rural catchment with mild topography and extensive share of arable land. The aim of the study was (i) to test the GIS-based IC calculation in specific topographic conditions, (ii) to assess the effects of land use changes on the sediment connectivity and (iii) to identify the landscape features affecting connection between hillslopes and stream channels. The study area - Loucka River Basin, Czech Republic with area of 386 sq km is located in highland landscape with 60% share of arable land. The basin study area has a reverse pattern of topography compared to the typical montane catchments - the extensive headwater areas, used for agriculture, are flat and are drained into steep valleys in downstream. The basin is equipped with long-term monitoring of suspended sediment transport. We have used the high resolution 5 meter DEM derived from aerial LiDAR scanning as a base for analysis of topographic controls of sediment connectivity and for calculation of connectivity topographic index. The index of connectivity was calculated in a multitemporal scale of two decades since 1990 to analyze the the changes of sediment connectivity and its spatial distribution in response to the

  9. Eccentric connectivity index

    CERN Document Server

    Ilić, Aleksandar

    2011-01-01

    The eccentric connectivity index $\\xi^c$ is a novel distance--based molecular structure descriptor that was recently used for mathematical modeling of biological activities of diverse nature. It is defined as $\\xi^c (G) = \\sum_{v \\in V (G)} deg (v) \\cdot \\epsilon (v)$\\,, where $deg (v)$ and $\\epsilon (v)$ denote the vertex degree and eccentricity of $v$\\,, respectively. We survey some mathematical properties of this index and furthermore support the use of eccentric connectivity index as topological structure descriptor. We present the extremal trees and unicyclic graphs with maximum and minimum eccentric connectivity index subject to the certain graph constraints. Sharp lower and asymptotic upper bound for all graphs are given and various connections with other important graph invariants are established. In addition, we present explicit formulae for the values of eccentric connectivity index for several families of composite graphs and designed a linear algorithm for calculating the eccentric connectivity in...

  10. On eccentric connectivity index

    CERN Document Server

    Zhou, Bo

    2010-01-01

    The eccentric connectivity index, proposed by Sharma, Goswami and Madan, has been employed successfully for the development of numerous mathematical models for the prediction of biological activities of diverse nature. We now report mathematical properties of the eccentric connectivity index. We establish various lower and upper bounds for the eccentric connectivity index in terms of other graph invariants including the number of vertices, the number of edges, the degree distance and the first Zagreb index. We determine the n-vertex trees of diameter with the minimum eccentric connectivity index, and the n-vertex trees of pendent vertices, with the maximum eccentric connectivity index. We also determine the n-vertex trees with respectively the minimum, second-minimum and third-minimum, and the maximum, second-maximum and third-maximum eccentric connectivity indices for

  11. Institutions for Asian Connectivity

    OpenAIRE

    Bhattacharyay, Biswa

    2010-01-01

    To make Asia more economically sustainable and resilient against external shocks, regional economies need to be rebalanced toward regional demand- and trade-driven growth through increased regional connectivity. The effectiveness of connectivity depends on the quality of hard and soft infrastructure. Of particular importance in terms of soft infrastructure which makes hard infrastructure work are the facilitating institutions that support connectivity through appropriate policies, reforms, sy...

  12. Handbook of networking & connectivity

    CERN Document Server

    McClain, Gary R

    1994-01-01

    Handbook of Networking & Connectivity focuses on connectivity standards in use, including hardware and software options. The book serves as a guide for solving specific problems that arise in designing and maintaining organizational networks.The selection first tackles open systems interconnection, guide to digital communications, and implementing TCP/IP in an SNA environment. Discussions focus on elimination of the SNA backbone, routing SNA over internets, connectionless versus connection-oriented networks, internet concepts, application program interfaces, basic principles of layering, proto

  13. Genomic connectivity networks based on the BrainSpan atlas of the developing human brain

    Science.gov (United States)

    Mahfouz, Ahmed; Ziats, Mark N.; Rennert, Owen M.; Lelieveldt, Boudewijn P. F.; Reinders, Marcel J. T.

    2014-03-01

    The human brain comprises systems of networks that span the molecular, cellular, anatomic and functional levels. Molecular studies of the developing brain have focused on elucidating networks among gene products that may drive cellular brain development by functioning together in biological pathways. On the other hand, studies of the brain connectome attempt to determine how anatomically distinct brain regions are connected to each other, either anatomically (diffusion tensor imaging) or functionally (functional MRI and EEG), and how they change over development. A global examination of the relationship between gene expression and connectivity in the developing human brain is necessary to understand how the genetic signature of different brain regions instructs connections to other regions. Furthermore, analyzing the development of connectivity networks based on the spatio-temporal dynamics of gene expression provides a new insight into the effect of neurodevelopmental disease genes on brain networks. In this work, we construct connectivity networks between brain regions based on the similarity of their gene expression signature, termed "Genomic Connectivity Networks" (GCNs). Genomic connectivity networks were constructed using data from the BrainSpan Transcriptional Atlas of the Developing Human Brain. Our goal was to understand how the genetic signatures of anatomically distinct brain regions relate to each other across development. We assessed the neurodevelopmental changes in connectivity patterns of brain regions when networks were constructed with genes implicated in the neurodevelopmental disorder autism (autism spectrum disorder; ASD). Using graph theory metrics to characterize the GCNs, we show that ASD-GCNs are relatively less connected later in development with the cerebellum showing a very distinct expression of ASD-associated genes compared to other brain regions.

  14. 78 FR 55684 - ConnectED Workshop

    Science.gov (United States)

    2013-09-11

    ... content into the curriculum; and as classroom management software tools move everything from homework... consider promising strategies for achieving the President's goal of connecting virtually all K-12 students... policies and consider the most promising strategies for equipping K-12 schools for digital learning....

  15. Inverse Degree and Connectivity

    Institute of Scientific and Technical Information of China (English)

    MA Xiao-ling; TIAN Ying-zhi

    2013-01-01

    Let G be a connected graph with vertex set V(G),order n =丨V(G)丨,minimum degree δ(G) and connectivity κ(G).The graph G is called maximally connected if κ(G) =δ(G).Define the inverse degree of G with no isolated vertices as R(G) =Σv∈V(G)1/d(v),where d(v) denotes the degree of the vertex v.We show that G is maximally connected if R(G) < 1 + 2/δ + n-2δ+1/(n-1)(n-3).

  16. Asymptotically hyperbolic connections

    Science.gov (United States)

    Fine, Joel; Herfray, Yannick; Krasnov, Kirill; Scarinci, Carlos

    2016-09-01

    General relativity in four-dimensions can be equivalently described as a dynamical theory of {SO}(3)˜ {SU}(2)-connections rather than metrics. We introduce the notion of asymptotically hyperbolic connections, and work out an analogue of the Fefferman-Graham expansion in the language of connections. As in the metric setup, one can solve the arising ‘evolution’ equations order by order in the expansion in powers of the radial coordinate. The solution in the connection setting is arguably simpler, and very straightforward algebraic manipulations allow one to see how the unconstrained by Einstein equations ‘stress-energy tensor’ appears at third order in the expansion. Another interesting feature of the connection formulation is that the ‘counter terms’ required in the computation of the renormalised volume all combine into the Chern-Simons functional of the restriction of the connection to the boundary. As the Chern-Simons invariant is only defined modulo large gauge transformations, the requirement that the path integral over asymptotically hyperbolic connections is well-defined requires the cosmological constant to be quantised. Finally, in the connection setting one can deform the 4D Einstein condition in an interesting way, and we show that asymptotically hyperbolic connection expansion is universal and valid for any of the deformed theories.

  17. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2015-01-01

    demands. We use a few axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well...... as all connection costs; (3) the central planner selects a cost minimizing network satisfying reported connection demands based on the estimated costs; and, (4) the planner allocates the true costs of the selected network. It turns out that an allocation rule satisfies the axioms if and only if relative...

  18. Comparing Structural Brain Connectivity by the Infinite Relational Model

    DEFF Research Database (Denmark)

    Ambrosen, Karen Marie Sandø; Herlau, Tue; Dyrby, Tim;

    2013-01-01

    The growing focus in neuroimaging on analyzing brain connectivity calls for powerful and reliable statistical modeling tools. We examine the Infinite Relational Model (IRM) as a tool to identify and compare structure in brain connectivity graphs by contrasting its performance on graphs from...... modeling tool for the identification of structure and quantification of similarity in graphs of brain connectivity in general....

  19. A Building Connecting Separated Communities

    DEFF Research Database (Denmark)

    Axel, Erik

    . in no systematic sequence. This, among other things, separates design and use, which is worth investigating in order to understand the problems involved in connecting the design of a house and analyzing the experience of a user. We undertook a preliminary investigation of how a dormitory for visiting students from...... with students from other dormitories, and connect with the Danes from other sections of the building isolating themselves. The janitor was surprised at the supposed function of the washing machines. Since other dormitories at the campus did not provide washing machines, the ones at the house investigated were...... in constant use, overloaded and noisy, making people stay away from the kitchen. With point of departure in this case, the nature of the spatial arrangements for the daily conduct of life are sketched out. The kitchen, hallways, washing machines and hotspots will be discussed as arrangements for accidental...

  20. Network based approaches reveal clustering in protein point patterns

    Science.gov (United States)

    Parker, Joshua; Barr, Valarie; Aldridge, Joshua; Samelson, Lawrence E.; Losert, Wolfgang

    2014-03-01

    Recent advances in super-resolution imaging have allowed for the sub-diffraction measurement of the spatial location of proteins on the surfaces of T-cells. The challenge is to connect these complex point patterns to the internal processes and interactions, both protein-protein and protein-membrane. We begin analyzing these patterns by forming a geometric network amongst the proteins and looking at network measures, such the degree distribution. This allows us to compare experimentally observed patterns to models. Specifically, we find that the experimental patterns differ from heterogeneous Poisson processes, highlighting an internal clustering structure. Further work will be to compare our results to simulated protein-protein interactions to determine clustering mechanisms.

  1. Connecting Arithmetic to Algebra

    Science.gov (United States)

    Darley, Joy W.; Leapard, Barbara B.

    2010-01-01

    Algebraic thinking is a top priority in mathematics classrooms today. Because elementary school teachers lay the groundwork to develop students' capacity to think algebraically, it is crucial for teachers to have a conceptual understanding of the connections between arithmetic and algebra and be confident in communicating these connections. Many…

  2. Tokens of Connection

    Science.gov (United States)

    Crowley, Theresa

    2016-01-01

    When teachers make the effort to build a solid relationship with each student, built on trust, they often engender a life-long connection, one that's life-changing for the student. But how can teachers grow such long-lasting relationships with all students, especially disenfranchised learners and those who make it hard to connect? Crowley, a…

  3. Making Connections with Estimation.

    Science.gov (United States)

    Lobato, Joanne E.

    1993-01-01

    Describes four methods to structure estimation activities that enable students to make connections between their understanding of numbers and extensions of those concepts to estimating. Presents activities that connect estimation with other curricular areas, other mathematical topics, and real-world applications. (MDH)

  4. Making Connections: Explorations in Creative Expression.

    Science.gov (United States)

    Hahn, Sidney L.

    A series of strategies called the "Synectics Model," can be used by teachers in helping students to break away from usual thought patterns and to make new connections. Its purpose is to increase creativity and to produce lateral thinking. The activities employed involve the use of metaphor. Examples of the model are provided that were…

  5. One Dimensional Locally Connected S-spaces

    CERN Document Server

    Kunen, Joan E Hart Kenneth

    2007-01-01

    We construct, assuming Jensen's principle diamond, a one-dimensional locally connected hereditarily separable continuum without convergent sequences. The construction is an inverse limit in omega_1 steps, and is patterned after the original Fedorchuk construction of a compact S-space. To make it one-dimensional, each space in the inverse limit is a copy of the Menger sponge.

  6. Generalized connectivity of graphs

    CERN Document Server

    Li, Xueliang

    2016-01-01

    Noteworthy results, proof techniques, open problems and conjectures in generalized (edge-) connectivity are discussed in this book. Both theoretical and practical analyses for generalized (edge-) connectivity of graphs are provided. Topics covered in this book include: generalized (edge-) connectivity of graph classes, algorithms, computational complexity, sharp bounds, Nordhaus-Gaddum-type results, maximum generalized local connectivity, extremal problems, random graphs, multigraphs, relations with the Steiner tree packing problem and generalizations of connectivity. This book enables graduate students to understand and master a segment of graph theory and combinatorial optimization. Researchers in graph theory, combinatorics, combinatorial optimization, probability, computer science, discrete algorithms, complexity analysis, network design, and the information transferring models will find this book useful in their studies.

  7. Handbook of Brain Connectivity

    CERN Document Server

    Jirsa, Viktor K

    2007-01-01

    Our contemporary understanding of brain function is deeply rooted in the ideas of the nonlinear dynamics of distributed networks. Cognition and motor coordination seem to arise from the interactions of local neuronal networks, which themselves are connected in large scales across the entire brain. The spatial architectures between various scales inevitably influence the dynamics of the brain and thereby its function. But how can we integrate brain connectivity amongst these structural and functional domains? Our Handbook provides an account of the current knowledge on the measurement, analysis and theory of the anatomical and functional connectivity of the brain. All contributors are leading experts in various fields concerning structural and functional brain connectivity. In the first part of the Handbook, the chapters focus on an introduction and discussion of the principles underlying connected neural systems. The second part introduces the currently available non-invasive technologies for measuring struct...

  8. Changes of functional and effective connectivity in smoking replenishment on deprived heavy smokers: a resting-state FMRI study.

    Science.gov (United States)

    Ding, Xiaoyu; Lee, Seong-Whan

    2013-01-01

    Previous researches have explored the changes of functional connectivity caused by smoking with the aid of fMRI. This study considers not only functional connectivity but also effective connectivity regarding both brain networks and brain regions by using a novel analysis framework that combines independent component analysis (ICA) and Granger causality analysis (GCA). We conducted a resting-state fMRI experiment in which twenty-one heavy smokers were scanned in two sessions of different conditions: smoking abstinence followed by smoking satiety. In our framework, group ICA was firstly adopted to obtain the spatial patterns of the default-mode network (DMN), executive-control network (ECN), and salience network (SN). Their associated time courses were analyzed using GCA, showing that the effective connectivity from SN to DMN was reduced and that from ECN/DMN to SN was enhanced after smoking replenishment. A paired t-test on ICA spatial patterns revealed functional connectivity variation in regions such as the insula, parahippocampus, precuneus, anterior cingulate cortex, supplementary motor area, and ventromedial/dorsolateral prefrontal cortex. These regions were later selected as the regions of interest (ROIs), and their effective connectivity was investigated subsequently using GCA. In smoking abstinence, the insula showed the increased effective connectivity with the other ROIs; while in smoking satiety, the parahippocampus had the enhanced inter-area effective connectivity. These results demonstrate our hypothesis that for deprived heavy smokers, smoking replenishment takes effect on both functional and effective connectivity. Moreover, our analysis framework could be applied in a range of neuroscience studies.

  9. Soft Decision Analyzer and Method

    Science.gov (United States)

    Steele, Glen F. (Inventor); Lansdowne, Chatwin (Inventor); Zucha, Joan P. (Inventor); Schlesinger, Adam M. (Inventor)

    2016-01-01

    A soft decision analyzer system is operable to interconnect soft decision communication equipment and analyze the operation thereof to detect symbol wise alignment between a test data stream and a reference data stream in a variety of operating conditions.

  10. Reflections on the specificity of synaptic connections.

    Science.gov (United States)

    White, Edward L

    2007-10-01

    The principal focus of this treatise is the specificity of synaptic connectivity in the mammalian central nervous system. The occurrence of stereotypical patterns of connection at the macro level (e.g., the general consistency with which axonal pathways impinge on and originate within specific cortical areas and layers) implies that the cerebral cortex is a highly ordered structure. Order is seen also at the more micro level of synaptic connectivity, for instance, in the contrasting synaptic patterns of spiny vs. non-spiny neurons. Quantitative electron microscopic studies of synapses between identified neurons and correlative anatomical/electrophysiological investigations indicate that the high degree of order characterizing many aspects of cortical organization is mirrored by an equally ordered arrangement of synaptic connections between specific types of neurons. The recognition of recurring synaptic patterns has generated increased support for the notion of synaptic specificity as opposed to randomness, and we have begun now to understand the role of specificity in cortical function. At the core of cortical processing lie myriad possibilities for computation provided by the wealth of synaptic connections involving each neuron. Specificity, by limiting possibilities for connection, imposes an order on synaptic interactions even as processes of dynamic selection or synaptic remodeling ensure the constant formation and dissolution of cortical circuits. Collectively, these operations make maximal use of the richness of cortical synaptic connections to produce a highly flexible system, irrespective of the degree of hard-wiring, mutability, randomness or specificity that obtains for cortical wiring at any particular time. A brief, historical account of developments leading to our current understanding of cortical synaptic organization will precede the presentation of evidence for synaptic specificity.

  11. Quantifying bicycle network connectivity.

    Science.gov (United States)

    Lowry, Michael; Loh, Tracy Hadden

    2017-02-01

    The intent of this study was to compare bicycle network connectivity for different types of bicyclists and different neighborhoods. Connectivity was defined as the ability to reach important destinations, such as grocery stores, banks, and elementary schools, via pathways or roads with low vehicle volumes and low speed limits. The analysis was conducted for 28 neighborhoods in Seattle, Washington under existing conditions and for a proposed bicycle master plan, which when complete will provide over 700 new bicycle facilities, including protected bike lanes, neighborhood greenways, and multi-use trails. The results showed different levels of connectivity across neighborhoods and for different types of bicyclists. Certain projects were shown to improve connectivity differently for confident and non-confident bicyclists. The analysis showed a positive correlation between connectivity and observed utilitarian bicycle trips. To improve connectivity for the majority of bicyclists, planners and policy-makers should provide bicycle facilities that allow immediate, low-stress access to the street network, such as neighborhood greenways. The analysis also suggests that policies and programs that build confidence for bicycling could greatly increase connectivity.

  12. Modeled Population Connectivity across the Hawaiian Archipelago.

    Science.gov (United States)

    Wren, Johanna L K; Kobayashi, Donald R; Jia, Yanli; Toonen, Robert J

    2016-01-01

    We present the first comprehensive estimate of connectivity of passive pelagic particles released from coral reef habitat throughout the Hawaiian Archipelago. Potential connectivity is calculated using a Lagrangian particle transport model coupled offline with currents generated by an oceanographic circulation model, MITgcm. The connectivity matrices show a surprising degree of self-recruitment and directional dispersal towards the northwest, from the Main Hawaiian Islands (MHI) to the northwestern Hawaiian Islands (NWHI). We identify three predicted connectivity breaks in the archipelago, that is, areas in the mid and northern part of the archipelago that have limited connections with surrounding islands and reefs. Predicted regions of limited connectivity generally match observed patterns of genetic structure reported for coral reef species in the uninhabited NWHI, but multiple genetic breaks observed in the inhabited MHI are not explained by passive dispersal. The better congruence in our modeling results based on physical transport of passive particles in the low-lying atolls of the uninhabited NWHI, but not in the anthropogenically impacted high islands of the MHI begs the question: what ultimately controls connectivity in this system?

  13. Covariant Magnetic Connection Hypersurfaces

    CERN Document Server

    Pegoraro, F

    2016-01-01

    In the single fluid, nonrelativistic, ideal-Magnetohydrodynamic (MHD) plasma description magnetic field lines play a fundamental role by defining dynamically preserved "magnetic connections" between plasma elements. Here we show how the concept of magnetic connection needs to be generalized in the case of a relativistic MHD description where we require covariance under arbitrary Lorentz transformations. This is performed by defining 2-D {\\it magnetic connection hypersurfaces} in the 4-D Minkowski space. This generalization accounts for the loss of simultaneity between spatially separated events in different frames and is expected to provide a powerful insight into the 4-D geometry of electromagnetic fields when ${\\bf E} \\cdot {\\bf B} = 0$.

  14. Singularities of invariant connections

    Energy Technology Data Exchange (ETDEWEB)

    Amores, A.M. (Universidad Complutense, Madrid (Spain)); Gutierrez, M. (Universidad Politecnica, Madrid (Spain))

    1992-12-01

    A reductive homogeneous space M = P/G is considered, endowed with an invariant connection, i.e., such that all left translations of M induced by members of P preserve it. The authors study the set of singularities of such connections giving sufficient conditions for it to be empty, or, in other cases, familities of b-incomplete curves converging to singularities. A full description of the b-completion of a connection with M = R[sup m] (or a quotient of it) is given with information on its topology. 5 refs.

  15. Directional connectivity in hydrology and ecology.

    Science.gov (United States)

    Larsen, Laurel G; Choi, Jungyill; Nungesser, Martha K; Harvey, Judson W

    2012-12-01

    subtle differences in the physical-biological feedbacks driving pattern formation. Case-study application of the DCI to the Everglades in south Florida revealed that loss of directional hydrologic connectivity occurs more rapidly and is a more sensitive indicator of declining ecosystem function than other metrics (e.g., habitat area) used previously. Here and elsewhere, directional connectivity can provide insight into landscape drivers and processes, act as an early-warning indicator of environmental degradation, and serve as a planning tool or performance measure for conservation and restoration efforts.

  16. Directional connectivity in hydrology and ecology

    Science.gov (United States)

    Larsen, Laurel G.; Choi, Jungyill; Nungesser, Martha K.; Harvey, Judson W.

    2012-01-01

    subtle differences in the physical-biological feedbacks driving pattern formation. Case-study application of the DCI to the Everglades in south Florida revealed that loss of directional hydrologic connectivity occurs more rapidly and is a more sensitive indicator of declining ecosystem function than other metrics (e.g., habitat area) used previously. Here and elsewhere, directional connectivity can provide insight into landscape drivers and processes, act as an early-warning indicator of environmental degradation, and serve as a planning tool or performance measure for conservation and restoration efforts.

  17. Spatial variability in hydrologic connectivity between a coastal river and its floodplain

    Science.gov (United States)

    Castillo, C. R.; Guneralp, I.; Hales, B. U.

    2015-12-01

    Significant in the transport and dispersal of energy, matter, and biota within riverine environments, hydrologic connectivity has become fundamental in understanding river-floodplain process and concepts associated with environmental flows. Hydrologic connectivity between a river and its floodplain is dependent on floodplain geomorphology, channel hydraulics, land cover, and groundwater dynamics. In this study, we examine the floodplain morphology of the Mission River on the Coastal Bend of Texas. Utilizing a LiDAR-derived digital elevation model, we develop a relative digital elevation model (RDEM), with respect to river-stage, for a reach of the river-floodplain system. To assess the dominant flow directions, and thus, characterize the connectivity within the floodplain, we determine hydrological facets—landscape patches with their own respective outlet and high internal surface water connectivity. Guided by historical streamflow records, we systematically threshold the RDEM to determine the spatial characteristics of floodplain inundation under various river-stages. The increasing aerial extent of floodplain inundation from increases in river-stage results in distinct patterns of river channel-floodplain connectivity. We analyze the spatial arrangement of facets with regard to inundation in order to quantify floodplain connectivity and complexity at various river-stages using graph theory and landscape metrics. Our results indicate that floodplain connectivity and complexity change nonlinearly with increases in river-stage; with the greatest increases in connectivity and complexity occurring well below bankfull discharge. Floodplains provide valuable ecosystem services and this study helps improve our understanding of process-form relationships in river-floodplain systems' that informs environmental policy for effective management of these services.

  18. Cerebral functional connectivity and Mayer waves in mice: Phenomena and separability.

    Science.gov (United States)

    Bumstead, Jonathan R; Bauer, Adam Q; Wright, Patrick W; Culver, Joseph P

    2017-02-01

    Resting-state functional connectivity is a growing neuroimaging approach that analyses the spatiotemporal structure of spontaneous brain activity, often using low-frequency (waves. Despite how close in frequency these phenomena exist, there is little research on how vasomotion and Mayer waves are related to or affect resting-state functional connectivity. In this study, we analyze spontaneous hemodynamic fluctuations over the mouse cortex using optical intrinsic signal imaging. We found spontaneous occurrence of oscillatory hemodynamics ∼0.2 Hz consistent with the properties of Mayer waves reported in the literature. Across a group of mice (n = 19), there was a large variability in the magnitude of Mayer waves. However, regardless of the magnitude of Mayer waves, functional connectivity patterns could be recovered from hemodynamic signals when filtered to the lower frequency band, 0.01-0.08 Hz. Our results demonstrate that both Mayer waves and resting-state functional connectivity patterns can co-exist simultaneously, and that they can be separated by applying bandpass filters.

  19. Strengthening connections: functional connectivity and brain plasticity

    OpenAIRE

    2014-01-01

    The ascendancy of functional neuroimaging has facilitated the addition of network-based approaches to the neuropsychologist’s toolbox for evaluating the sequelae of brain insult. In particular, intrinsic functional connectivity (iFC) mapping of resting state fMRI (R-fMRI) data constitutes an ideal approach to measuring macro-scale networks in the human brain. Beyond the value of iFC mapping for charting how the functional topography of the brain is altered by insult and injury, iFC analyses c...

  20. Connective Tissue Naevus

    Directory of Open Access Journals (Sweden)

    Bhat Ramesh M

    1999-01-01

    Full Text Available A young adult female patient of connective tissue naevus presented with papules and indurated plaques on both les and left arm. Histopathology showed increased amount of collagen in the dermis. Osteopoikilosis was absent.

  1. Reliability of power connections

    Institute of Scientific and Technical Information of China (English)

    BRAUNOVIC Milenko

    2007-01-01

    Despite the use of various preventive maintenance measures, there are still a number of problem areas that can adversely affect system reliability. Also, economical constraints have pushed the designs of power connections closer to the limits allowed by the existing standards. The major parameters influencing the reliability and life of Al-Al and Al-Cu connections are identified. The effectiveness of various palliative measures is determined and the misconceptions about their effectiveness are dealt in detail.

  2. NEACP Onboard Connectivity Study

    Science.gov (United States)

    1990-03-30

    Methodology Framework .............................. 6-3 6.2.2 Sources of ME Cost Savings with NOCH ............... 6-5 6.2.3 Additional Benefits of 1OCU...processing system (MPS) installation connects all record and data communications equipment to a common MIL -STD-1553B bus and automates many of the manual...Local Area Network Concepts A NOCH developed around a generic bus would provide connectivity throughout the aircraft, thereby reducing or eliminating

  3. Scattering by a topological defect connecting two asymptotically Minkowski spacetimes

    CERN Document Server

    Pitelli, J P M

    2015-01-01

    We study the stability and the scattering properties of a spacetime with a topological defect along a spherical bubble. This bubble connects two flat spacetimes which are asymptotically Minkowski, so that the resulting universe may be regarded as containing a wormhole. Its distinguished feature is the absence of exotic matter, i.e., its matter content respects all the energy conditions. Although this wormhole is nontraversable, waves and quantum particles can tunnel between both universes. Interestingly enough, the wave equation alone does not uniquely determine the evolution of scalar waves on this background, and the theory of self-adjoint extensions of symmetric operators is required to find the relevant boundary conditions in this context. Here we show that, for a particular boundary condition, this spacetime is stable and gives rise to a scattering pattern which is identical to the more usual thin-shell wormhole composed of exotic matter. Other boundary conditions of interest are also analyzed, including...

  4. [Connective tissue and inflammation].

    Science.gov (United States)

    Jakab, Lajos

    2014-03-23

    The author summarizes the structure of the connective tissues, the increasing motion of the constituents, which determine the role in establishing the structure and function of that. The structure and function of the connective tissue are related to each other in the resting as well as inflammatory states. It is emphasized that cellular events in the connective tissue are part of the defence of the organism, the localisation of the damage and, if possible, the maintenance of restitutio ad integrum. The organism responds to damage with inflammation, the non specific immune response, as well as specific, adaptive immunity. These processes are located in the connective tissue. Sterile and pathogenic inflammation are relatively similar processes, but inevitable differences are present, too. Sialic acids and glycoproteins containing sialic acids have important roles, and the role of Siglecs is also highlighted. Also, similarities and differences in damages caused by pathogens and sterile agents are briefly summarized. In addition, the roles of adhesion molecules linked to each other, and the whole event of inflammatory processes are presented. When considering practical consequences it is stressed that the structure (building up) of the organism and the defending function of inflammation both have fundamental importance. Inflammation has a crucial role in maintaining the integrity and the unimpaired somato-psychological state of the organism. Thus, inflammation serves as a tool of organism identical with the natural immune response, inseparably connected with the specific, adaptive immune response. The main events of the inflammatory processes take place in the connective tissue.

  5. Connection Design in Cultivation of Secondary and Senior Skilled Talents of Automobile Maintenance---Taking the Pattern of Continuous Education of Secondary and Senior Technicians%汽修专业中高级技能型人才培养的衔接性设计--以天津市劳动经济学校中高技连读模式为例

    Institute of Scientific and Technical Information of China (English)

    林岩; 张鹏炜

    2015-01-01

    我校汽车运用与维修专业是天津市骨干专业,是我校开展三年制中专教育和两年制高级技工连读教育专业,在专业建设中,我校从中专教育和高技教育的有效衔接出发,对专业建设的岗位需求、培养目标、师资建设等方面进行了分段技能培养的全方位设计,明确了“三段能力递进、三项证书融通”的工学交替人才培养模式,构建了“两大模块、四大平台”的课程体系,为学生的继续学习和持续发展奠定了基础。%The major of automobile operation and maintenance in Tianjin School of Labor and E‐conomy is the key major in Tianjin ,which adopts connection of three -year secondary education and two-year senior technical education .During the major construction ,starting from effective connection of secondary education and senior technical education ,the school designs sectional skill training in an all-round manner from the aspects of job requirements ,cultivation object and construction of teachers ’ team and so on ,determines talent cultivation pattern of alternation of working with learning - three-section ability progression and three -certificate connection ,establishes curriculum system with “two modules and four platforms” ,and lays the foundation for students’ continuous studying and sustainable development .

  6. The Chess and Mathematics Connection: More than Just a Game

    Science.gov (United States)

    Berkman, Robert M.

    2004-01-01

    This article describes connections between chess and mathematics, including examples of activities that connect chess with set theory, patterns, algebra, geometry, combinatorics, and Pascal's triangle. The author observes that competitive games play a dual purpose in advancing the work of mathematics educators: to reinforce a specific skill and to…

  7. Scale of habitat connectivity and colonization in fragmented nuthatch populations

    NARCIS (Netherlands)

    Langevelde, van F.

    2000-01-01

    Studies of effects of landscape pattern on population dynamics should consider the spatial scale at which habitat connectivity varies relative to the spatial scale of the species' behavioral response. In this paper, I investigate the relationship between the degree of connectivity of wooded patches

  8. The multimodal connectivity of the hippocampal complex in auditory and visual hallucinations.

    Science.gov (United States)

    Amad, A; Cachia, A; Gorwood, P; Pins, D; Delmaire, C; Rolland, B; Mondino, M; Thomas, P; Jardri, R

    2014-02-01

    Hallucinations constitute one of the most representative and disabling symptoms of schizophrenia. Several Magnetic Resonance Imaging (MRI) findings support the hypothesis that distinct patterns of connectivity, particularly within networks involving the hippocampal complex (HC), could be associated with different hallucinatory modalities. The aim of this study was to investigate HC connectivity as a function of the hallucinatory modality, that is, auditory or visual. Two carefully selected subgroups of schizophrenia patients with only auditory hallucinations (AH) or with audio-visual hallucinations (A+VH) were compared using the following three complementary multimodal MRI methods: resting state functional MRI, diffusion MRI and structural MRI were used to analyze seed-based Functional Connectivity (sb-FC), Tract-Based Spatial Statistics (TBSS) and shape analysis, respectively. Sb-FC was significantly higher between the HC, the medial prefrontal cortex (mPFC) and the caudate nuclei in A+VH patients compared with the AH group. Conversely, AH patients exhibited a higher sb-FC between the HC and the thalamus in comparison with the A+VH group. In the A+VH group, TBSS showed specific higher white matter connectivity in the pathways connecting the HC with visual areas, such as the forceps major and the inferior-fronto-occipital fasciculus than in the AH group. Finally, shape analysis showed localized hippocampal hypertrophy in the A+VH group. Functional results support the fronto-limbic dysconnectivity hypothesis of schizophrenia, while specific structural findings indicate that plastic changes are associated with hallucinations. Together, these results suggest that there are distinct connectivity patterns in patients with schizophrenia that depend on the sensory-modality, with specific involvement of the HC in visual hallucinations.

  9. The connective tissue of the adductor canal--a morphological study in fetal and adult specimens.

    Science.gov (United States)

    de Oliveira, Flavia; de Vasconcellos Fontes, Ricardo Bragança; da Silva Baptista, Josemberg; Mayer, William Paganini; de Campos Boldrini, Silvia; Liberti, Edson Aparecido

    2009-03-01

    The adductor canal is a conical or pyramid-shaped pathway that contains the femoral vessels, saphenous nerve and a varying amount of fibrous tissue. It is involved in adductor canal syndrome, a claudication syndrome involving young individuals. Our objective was to study modifications induced by aging on the connective tissue and to correlate them to the proposed pathophysiological mechanism. The bilateral adductor canals and femoral vessels of four adult and five fetal specimens were removed en bloc and analyzed. Sections 12 microm thick were obtained and the connective tissue studied with Sirius Red, Verhoeff, Weigert and Azo stains. Scanning electron microscopy (SEM) photomicrographs of the surfaces of each adductor canal were also analyzed. Findings were homogeneous inside each group. The connective tissue of the canal was continuous with the outer layer of the vessels in both groups. The pattern of concentric, thick collagen type I bundles in fetal specimens was replaced by a diffuse network of compact collagen bundles with several transversal fibers and an impressive content of collagen III fibers. Elastic fibers in adults were not concentrated in the thick bundles but dispersed in line with the transversal fiber system. A dynamic compression mechanism with or without an evident constricting fibrous band has been proposed previously for adductor canal syndrome, possibly involving the connective tissue inside the canal. The vessels may not slide freely during movement. These age-related modifications in normal individuals may represent necessary conditions for this syndrome to develop.

  10. Using computational models to relate structural and functional brain connectivity.

    Science.gov (United States)

    Hlinka, Jaroslav; Coombes, Stephen

    2012-07-01

    Modern imaging methods allow a non-invasive assessment of both structural and functional brain connectivity. This has lead to the identification of disease-related alterations affecting functional connectivity. The mechanism of how such alterations in functional connectivity arise in a structured network of interacting neural populations is as yet poorly understood. Here we use a modeling approach to explore the way in which this can arise and to highlight the important role that local population dynamics can have in shaping emergent spatial functional connectivity patterns. The local dynamics for a neural population is taken to be of the Wilson-Cowan type, whilst the structural connectivity patterns used, describing long-range anatomical connections, cover both realistic scenarios (from the CoComac database) and idealized ones that allow for more detailed theoretical study. We have calculated graph-theoretic measures of functional network topology from numerical simulations of model networks. The effect of the form of local dynamics on the observed network state is quantified by examining the correlation between structural and functional connectivity. We document a profound and systematic dependence of the simulated functional connectivity patterns on the parameters controlling the dynamics. Importantly, we show that a weakly coupled oscillator theory explaining these correlations and their variation across parameter space can be developed. This theoretical development provides a novel way to characterize the mechanisms for the breakdown of functional connectivity in diseases through changes in local dynamics.

  11. Pattern matching

    NARCIS (Netherlands)

    A. Hak (Tony); J. Dul (Jan)

    2009-01-01

    textabstractPattern matching is comparing two patterns in order to determine whether they match (i.e., that they are the same) or do not match (i.e., that they differ). Pattern matching is the core procedure of theory-testing with cases. Testing consists of matching an “observed pattern” (a pattern

  12. Analyzing Valuation Practices through Contracts

    DEFF Research Database (Denmark)

    Tesnière, Germain; Labatut, Julie; Boxenbaum, Eva

    This paper seeks to analyze the most recent changes in how societies value animals. We analyze this topic through the prism of contracts between breeding companies and farmers. Focusing on new valuation practices and qualification of breeding animals, we question the evaluation of difficult...

  13. Analyzing data files in SWAN

    CERN Document Server

    Gajam, Niharika

    2016-01-01

    Traditionally analyzing data happens via batch-processing and interactive work on the terminal. The project aims to provide another way of analyzing data files: A cloud-based approach. It aims to make it a productive and interactive environment through the combination of FCC and SWAN software.

  14. Spatial organization and connectivity of caves

    Science.gov (United States)

    Jouves, Johan; Viseur, Sophie; Guglielmi, Yves; Camus, Hubert

    2015-04-01

    The main particularity of karst systems is their hierarchical organization as three-dimensional network of conduits behaving as drain. They are recognized as having a major influence on fluid flow at reservoir scale. However, a karstic network is generally hardly continuously observable and their great intrinsic heterogeneity makes their characterization very complex. This media can be only observed by speleological investigation, conditioned to human possibilities. As a result, only few parts can be observed and therefore it is required to model the non-observable parts for reservoir characterizations. To provide realistic 3D models, non-observable karstic features will be generated using parameters extracted from observed ones. Morphometric analysis of the three-dimensional karstic network provides quantitative measures that can (i) give information on speleogenesis processes, (ii) be used to compare different karst systems, (iii) be correlated with hydrogeological behavior and (iii) control the simulation of realistic karst networks. Recent work done on the subject characterize the karstic network as a whole, without genetic a-priori. However, most of observable caves appears to have a polygenic history due to modifications in boundary conditions and some different karst features can be observed in a same cavity. To study the geometrical organization of caves, we propose to analyze 3D speleological topographies for which speleogenetic context is known. This way, it is possible to characterize karst features according to speleogenetic processes. Several morphometric descriptors have been calculated on three-dimensional topographies provided by speleological works. Some parameters describe the existence of preferential direction of karstification and preferential flow paths, other parameters describe the complexity, geometry and connectivity of the three-dimensional karstic networks. Through the study of fifteen different caves, 150km of 3D data have been analyzed

  15. Analyzing visual signals as visual scenes.

    Science.gov (United States)

    Allen, William L; Higham, James P

    2013-07-01

    The study of visual signal design is gaining momentum as techniques for studying signals become more sophisticated and more freely available. In this paper we discuss methods for analyzing the color and form of visual signals, for integrating signal components into visual scenes, and for producing visual signal stimuli for use in psychophysical experiments. Our recommended methods aim to be rigorous, detailed, quantitative, objective, and where possible based on the perceptual representation of the intended signal receiver(s). As methods for analyzing signal color and luminance have been outlined in previous publications we focus on analyzing form information by discussing how statistical shape analysis (SSA) methods can be used to analyze signal shape, and spatial filtering to analyze repetitive patterns. We also suggest the use of vector-based approaches for integrating multiple signal components. In our opinion elliptical Fourier analysis (EFA) is the most promising technique for shape quantification but we await the results of empirical comparison of techniques and the development of new shape analysis methods based on the cognitive and perceptual representations of receivers. Our manuscript should serve as an introductory guide to those interested in measuring visual signals, and while our examples focus on primate signals, the methods are applicable to quantifying visual signals in most taxa.

  16. Non-standard connections in classical mechanics

    CERN Document Server

    Echeverría-Enríquez, A; Román-Roy, N

    1995-01-01

    In the jet-bundle description of first-order classical field theories there are some elements, such as the lagrangian energy and the construction of the hamiltonian formalism, which require the prior choice of a connection. Bearing these facts in mind, we analyze the situation in the jet-bundle description of time-dependent classical mechanics. So we prove that this connection-dependence also occurs in this case, although it is usually hidden by the use of the ``natural'' connection given by the trivial bundle structure of the phase spaces in consideration. However, we also prove that this dependence is dynamically irrelevant, except where the dynamical variation of the energy is concerned. In addition, the relationship between first integrals and connections is shown for a large enough class of lagrangians.

  17. Heritable Disorders of Connective Tissue

    Science.gov (United States)

    ... Connective Tissue Find a Clinical Trial Journal Articles Connective Tissue August 2016 Questions and Answers about Heritable Disorders of Connective Tissue This publication contains general information about heritable (genetic) ...

  18. Algebraic connectivity and graph robustness.

    Energy Technology Data Exchange (ETDEWEB)

    Feddema, John Todd; Byrne, Raymond Harry; Abdallah, Chaouki T. (University of New Mexico)

    2009-07-01

    Recent papers have used Fiedler's definition of algebraic connectivity to show that network robustness, as measured by node-connectivity and edge-connectivity, can be increased by increasing the algebraic connectivity of the network. By the definition of algebraic connectivity, the second smallest eigenvalue of the graph Laplacian is a lower bound on the node-connectivity. In this paper we show that for circular random lattice graphs and mesh graphs algebraic connectivity is a conservative lower bound, and that increases in algebraic connectivity actually correspond to a decrease in node-connectivity. This means that the networks are actually less robust with respect to node-connectivity as the algebraic connectivity increases. However, an increase in algebraic connectivity seems to correlate well with a decrease in the characteristic path length of these networks - which would result in quicker communication through the network. Applications of these results are then discussed for perimeter security.

  19. Linear connections on matrix geometries

    CERN Document Server

    Madore, J; Mourad, J; Madore, John; Masson, Thierry; Mourad, Jihad

    1994-01-01

    A general definition of a linear connection in noncommutative geometry has been recently proposed. Two examples are given of linear connections in noncommutative geometries which are based on matrix algebras. They both possess a unique metric connection.

  20. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  1. ANALYZE Users' Guide

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, S.

    1982-10-01

    This report is a reproduction of the visuals that were used in the ANALYZE Users' Guide lectures of the videotaped LLNL Continuing Education Course CE2018-H, State Space Lectures. The course was given in Spring 1982 through the EE Department Education Office. Since ANALYZE is menu-driven, interactive, and has self-explanatory questions (sort of), these visuals and the two 50-minute videotapes are the only documentation which comes with the code. More information about the algorithms contained in ANALYZE can be obtained from the IEEE book on Programs for Digital Signal Processing.

  2. Connectivity analysis of one-dimensional ad-hoc networks

    DEFF Research Database (Denmark)

    Hansen, Martin Bøgsted; Rasmussen, Jakob Gulddahl; Schwefel, Hans-Peter

    Applications and communication protocols in dynamic ad-hoc networks are exposed to physical limitations imposed by the connectivity relations that result from mobility. Motivated by vehicular freeway scenarios, this paper analyzes a number of important connectivity metrics for instantaneous...... hop-count; (3) the connectivity distance, expressing the geographic distance that a message can be propagated in the network on multi-hop paths; (4) the connectivity hops, which corresponds to the number of hops that are necessary to reach all nodes in the connected network. The paper develops...

  3. Developmental Changes in Brain Network Hub Connectivity in Late Adolescence.

    Science.gov (United States)

    Baker, Simon T E; Lubman, Dan I; Yücel, Murat; Allen, Nicholas B; Whittle, Sarah; Fulcher, Ben D; Zalesky, Andrew; Fornito, Alex

    2015-06-17

    The human brain undergoes substantial development throughout adolescence and into early adulthood. This maturational process is thought to include the refinement of connectivity between putative connectivity hub regions of the brain, which collectively form a dense core that enhances the functional integration of anatomically distributed, and functionally specialized, neural systems. Here, we used longitudinal diffusion magnetic resonance imaging to characterize changes in connectivity between 80 cortical and subcortical anatomical regions over a 2 year period in 31 adolescents between the ages of 15 and 19 years. Connectome-wide analysis indicated that only a small subset of connections showed evidence of statistically significant developmental change over the study period, with 8% and 6% of connections demonstrating decreased and increased structural connectivity, respectively. Nonetheless, these connections linked 93% and 90% of the 80 regions, respectively, pointing to a selective, yet anatomically distributed pattern of developmental changes that involves most of the brain. Hub regions showed a distinct tendency to be highly connected to each other, indicating robust "rich-club" organization. Moreover, connectivity between hubs was disproportionately influenced by development, such that connectivity between subcortical hubs decreased over time, whereas frontal-subcortical and frontal-parietal hub-hub connectivity increased over time. These findings suggest that late adolescence is characterized by selective, yet significant remodeling of hub-hub connectivity, with the topological organization of hubs shifting emphasis from subcortical hubs in favor of an increasingly prominent role for frontal hub regions.

  4. The CONNECT project

    DEFF Research Database (Denmark)

    Assaf, Yaniv; Alexander, Daniel C; Jones, Derek K

    2013-01-01

    diameter and axonal density). This unique insight into both tissue microstructure and connectivity has enormous potential value in understanding the structure and organization of the brain as well as providing unique insights to abnormalities that underpin disease states. The CONNECT (Consortium......In recent years, diffusion MRI has become an extremely important tool for studying the morphology of living brain tissue, as it provides unique insights into both its macrostructure and microstructure. Recent applications of diffusion MRI aimed to characterize the structural connectome using...... tractography to infer connectivity between brain regions. In parallel to the development of tractography, additional diffusion MRI based frameworks (CHARMED, AxCaliber, ActiveAx) were developed enabling the extraction of a multitude of micro-structural parameters (axon diameter distribution, mean axonal...

  5. Skeletal muscle connective tissue

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline

      The connective tissue content of skeletal muscle is believed to be the major factor responsible for defining the eating quality of different meat cuts, although attempts to correlate quantifications based on traditional histological methods have not as yet been able to prove this relation....... Collagen, being the major protein in connective tissue, has been extensively investigated with regard to its relation to meat tenderness, but the results have been rather conflicting. Meat from older animals is tougher than that from younger animals, and changes in the properties of the collagen due...... that collagen plays a significant role in determining the tenderness of meat. What are we missing? Therefore, fundamental aspects of connective tissue research have been the centre of attention throughout this thesis. A holistic view has been applied, glancing at this complex tissue which has many facets...

  6. Connectivity and superconductivity

    CERN Document Server

    Rubinstein, Jacob

    2000-01-01

    The motto of connectivity and superconductivity is that the solutions of the Ginzburg--Landau equations are qualitatively influenced by the topology of the boundaries, as in multiply-connected samples. Special attention is paid to the "zero set", the set of the positions (also known as "quantum vortices") where the order parameter vanishes. The effects considered here usually become important in the regime where the coherence length is of the order of the dimensions of the sample. It takes the intuition of physicists and the awareness of mathematicians to find these new effects. In connectivity and superconductivity, theoretical and experimental physicists are brought together with pure and applied mathematicians to review these surprising results. This volume is intended to serve as a reference book for graduate students and researchers in physics or mathematics interested in superconductivity, or in the Schrödinger equation as a limiting case of the Ginzburg--Landau equations.

  7. Design for CNN Templates with Performance of Global Connectivity Detection

    Institute of Scientific and Technical Information of China (English)

    LIU Jin-Zhu; MIN Le-Quan

    2004-01-01

    The cellular neural/nonlinear network (CNN) is a powerful tool for image and video signal processing,robotic and biological visions. This paper discusses a general method for designing template of the global connectivity detection (GCD) CNN, which provides parameter inequalities for determining parameter intervals for implementing the corresponding functions. The GCD CNN has stronger ability and faster rate for determining global connectivity in binary patterns than the GCD CNN proposed by Zarandy. An example for detecting the connectivity in complex patterns is given.

  8. Best connected rectangular arrangements

    Directory of Open Access Journals (Sweden)

    Krishnendra Shekhawat

    2016-03-01

    Full Text Available It can be found quite often in the literature that many well-known architects have employed either the golden rectangle or the Fibonacci rectangle in their works. On contrary, it is rare to find any specific reason for using them so often. Recently, Shekhawat (2015 proved that the golden rectangle and the Fibonacci rectangle are one of the best connected rectangular arrangements and this may be one of the reasons for their high presence in architectural designs. In this work we present an algorithm that generates n-4 best connected rectangular arrangements so that the proposed solutions can be further used by architects for their designs.

  9. Resting-state functional connectivity of orthographic networks in acquired dysgraphia

    Directory of Open Access Journals (Sweden)

    Gali Ellenblum

    2015-05-01

    The NTA findings indicate that the relationship between orthographic and default-mode networks is characterized by greater within- vs. across-network connectivity. Furthermore, we show for the first time a pattern of increasing within/across network “coherence normalization” following spelling rehabilitation. Additional dysgraphic participants and other networks (language, sensory-motor, etc. will be analyzed to develop a better understanding of the RS orthographic network and its response to damage and recovery. Acknowledgements. The work is part of a multi-site, NIDCD-supported project examining language recovery neurobiology in aphasia (DC006740. We thank Melissa Greenberger and Xiao-Wei Song.

  10. C2Analyzer:Co-target-Co-function Analyzer

    Institute of Scientific and Technical Information of China (English)

    Md Aftabuddin; Chittabrata Mal; Arindam Deb; Sudip Kundu

    2014-01-01

    MicroRNAs (miRNAs) interact with their target mRNAs and regulate biological pro-cesses at post-transcriptional level. While one miRNA can target many mRNAs, a single mRNA can also be targeted by a set of miRNAs. The targeted mRNAs may be involved in different bio-logical processes that are described by gene ontology (GO) terms. The major challenges involved in analyzing these multitude regulations include identification of the combinatorial regulation of miR-NAs as well as determination of the co-functionally-enriched miRNA pairs. The C2Analyzer:Co-target-Co-function Analyzer, is a Perl-based, versatile and user-friendly web tool with online instructions. Based on the hypergeometric analysis, this novel tool can determine whether given pairs of miRNAs are co-functionally enriched. For a given set of GO term(s), it can also identify the set of miRNAs whose targets are enriched in the given GO term(s). Moreover, C2Analyzer can also identify the co-targeting miRNA pairs, their targets and GO processes, which they are involved in. The miRNA-miRNA co-functional relationship can also be saved as a .txt file, which can be used to further visualize the co-functional network by using other software like Cytoscape. C2Analyzer is freely available at www.bioinformatics.org/c2analyzer.

  11. Interpreting the effects of altered brain anatomical connectivity on fMRI functional connectivity: a role for computational neural modeling.

    Science.gov (United States)

    Horwitz, Barry; Hwang, Chuhern; Alstott, Jeff

    2013-01-01

    Recently, there have been a large number of studies using resting state fMRI to characterize abnormal brain connectivity in patients with a variety of neurological, psychiatric, and developmental disorders. However, interpreting what the differences in resting state fMRI functional connectivity (rsfMRI-FC) actually reflect in terms of the underlying neural pathology has proved to be elusive because of the complexity of brain anatomical connectivity. The same is the case for task-based fMRI studies. In the last few years, several groups have used large-scale neural modeling to help provide some insight into the relationship between brain anatomical connectivity and the corresponding patterns of fMRI-FC. In this paper we review several efforts at using large-scale neural modeling to investigate the relationship between structural connectivity and functional/effective connectivity to determine how alterations in structural connectivity are manifested in altered patterns of functional/effective connectivity. Because the alterations made in the anatomical connectivity between specific brain regions in the model are known in detail, one can use the results of these simulations to determine the corresponding alterations in rsfMRI-FC. Many of these simulation studies found that structural connectivity changes do not necessarily result in matching changes in functional/effective connectivity in the areas of structural modification. Often, it was observed that increases in functional/effective connectivity in the altered brain did not necessarily correspond to increases in the strength of the anatomical connection weights. Note that increases in rsfMRI-FC in patients have been interpreted in some cases as resulting from neural plasticity. These results suggest that this interpretation can be mistaken. The relevance of these simulation findings to the use of functional/effective fMRI connectivity as biomarkers for brain disorders is also discussed.

  12. Connectivity within and among a network of temperate marine reserves.

    Directory of Open Access Journals (Sweden)

    Melinda A Coleman

    Full Text Available Networks of marine reserves are increasingly being promoted as a means of conserving marine biodiversity. One consideration in designing systems of marine reserves is the maintenance of connectivity to ensure the long-term persistence and resilience of populations. Knowledge of connectivity, however, is frequently lacking during marine reserve design and establishment. We characterise patterns of genetic connectivity of 3 key species of habitat-forming macroalgae across an established network of temperate marine reserves on the east coast of Australia and the implications for adaptive management and marine reserve design. Connectivity varied greatly among species. Connectivity was high for the subtidal macroalgae Ecklonia radiata and Phyllospora comosa and neither species showed any clear patterns of genetic structuring with geographic distance within or among marine parks. In contrast, connectivity was low for the intertidal, Hormosira banksii, and there was a strong pattern of isolation by distance. Coastal topography and latitude influenced small scale patterns of genetic structure. These results suggest that some species are well served by the current system of marine reserves in place along this temperate coast but it may be warranted to revisit protection of intertidal habitats to ensure the long-term persistence of important habitat-forming macroalgae. Adaptively managing marine reserve design to maintain connectivity may ensure the long-term persistence and resilience of marine habitats and the biodiversity they support.

  13. Connectivity within and among a network of temperate marine reserves.

    Science.gov (United States)

    Coleman, Melinda A; Chambers, Justine; Knott, Nathan A; Malcolm, Hamish A; Harasti, David; Jordan, Alan; Kelaher, Brendan P

    2011-01-01

    Networks of marine reserves are increasingly being promoted as a means of conserving marine biodiversity. One consideration in designing systems of marine reserves is the maintenance of connectivity to ensure the long-term persistence and resilience of populations. Knowledge of connectivity, however, is frequently lacking during marine reserve design and establishment. We characterise patterns of genetic connectivity of 3 key species of habitat-forming macroalgae across an established network of temperate marine reserves on the east coast of Australia and the implications for adaptive management and marine reserve design. Connectivity varied greatly among species. Connectivity was high for the subtidal macroalgae Ecklonia radiata and Phyllospora comosa and neither species showed any clear patterns of genetic structuring with geographic distance within or among marine parks. In contrast, connectivity was low for the intertidal, Hormosira banksii, and there was a strong pattern of isolation by distance. Coastal topography and latitude influenced small scale patterns of genetic structure. These results suggest that some species are well served by the current system of marine reserves in place along this temperate coast but it may be warranted to revisit protection of intertidal habitats to ensure the long-term persistence of important habitat-forming macroalgae. Adaptively managing marine reserve design to maintain connectivity may ensure the long-term persistence and resilience of marine habitats and the biodiversity they support.

  14. Strengthening connections: functional connectivity and brain plasticity.

    Science.gov (United States)

    Kelly, Clare; Castellanos, F Xavier

    2014-03-01

    The ascendancy of functional neuroimaging has facilitated the addition of network-based approaches to the neuropsychologist's toolbox for evaluating the sequelae of brain insult. In particular, intrinsic functional connectivity (iFC) mapping of resting state fMRI (R-fMRI) data constitutes an ideal approach to measuring macro-scale networks in the human brain. Beyond the value of iFC mapping for charting how the functional topography of the brain is altered by insult and injury, iFC analyses can provide insights into experience-dependent plasticity at the macro level of large-scale functional networks. Such insights are foundational to the design of training and remediation interventions that will best facilitate recovery of function. In this review, we consider what is currently known about the origin and function of iFC in the brain, and how this knowledge is informative in neuropsychological settings. We then summarize studies that have examined experience-driven plasticity of iFC in healthy control participants, and frame these findings in terms of a schema that may aid in the interpretation of results and the generation of hypotheses for rehabilitative studies. Finally, we outline some caveats to the R-fMRI approach, as well as some current developments that are likely to bolster the utility of the iFC paradigm for neuropsychology.

  15. Connectivity-Based Watermarking Robust to Geometrical Attacks

    Institute of Scientific and Technical Information of China (English)

    Wang Hongxia; Luo Jian

    2006-01-01

    A novel robust watermarking scheme based on image connectivity is proposed. In the scheme, the connected objects are obtained according to selected connectivity pattern, and the gravity centers are calculated in several bigger objects as the reference points for watermark embedding. Based on these reference points and the center of the whole image, several sectors are formed, and the same version of watermarks is embedded into these sectors and their opposites. Thanks to the very stable gravity center of the connected objects, watermark detection is synchronized successfully. Simulation results show that the watermark can survive under both local and global geometrical distortions.

  16. 18.CONNECTIVE TISSUE DISORDER

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930734 Measurement of serum soluble interleukin—2 receptor in connective tissue diseases.CAI Houronget al.Dept Intern Med,Affili Gulou Hosp,Med School,Nanjing Univ,Nanjing,210008,ShanghaiJ Immunol 1993;13(4):216—218December 1993 Vol 10 No 4

  17. Connecting Competing Memories

    NARCIS (Netherlands)

    Laarse, van der R.; Saloul, I.A.M.

    Research Expert Meeting: Connecting Competing Memories of War in Contemporary Europe5 March 2014NIAS hosts, 6 - 7 March, the expert meeting of the Consortium for 'The Cultural Heritage of War in Contemporary Europe'. The aim is to draft main themes and discuss financial and research structures regar

  18. The Anansi Connection.

    Science.gov (United States)

    Carger, Chris Liska

    1998-01-01

    Describes a teacher educator's efforts to connect children's literature, sponsored by a partnership between Northern Illinois University and Chicago Public Schools. In one project, student teachers used award-winning picture books to inspire African-American eighth graders to create pastels on black paper. In another, regional folk tales inspired…

  19. Technology and Internet Connections.

    Science.gov (United States)

    Allen, Denise; Lindroth, Linda

    1996-01-01

    Suggests that teachers can use computer software and Internet connections to enhance curriculum and capitalize student's natural interest in sports and sports figures. Provides a list of activities that students can do in relation to the Olympic games and gives information on how technology can assist in such activities. Appropriate Internet…

  20. Wireless Connectivity and Capacity

    CERN Document Server

    Halldorsson, Magnus M

    2011-01-01

    Given $n$ wireless transceivers located in a plane, a fundamental problem in wireless communications is to construct a strongly connected digraph on them such that the constituent links can be scheduled in fewest possible time slots, assuming the SINR model of interference. In this paper, we provide an algorithm that connects an arbitrary point set in $O(\\log n)$ slots, improving on the previous best bound of $O(\\log^2 n)$ due to Moscibroda. This is complemented with a super-constant lower bound on our approach to connectivity. An important feature is that the algorithms allow for bi-directional (half-duplex) communication. One implication of this result is an improved bound of $\\Omega(1/\\log n)$ on the worst-case capacity of wireless networks, matching the best bound known for the extensively studied average-case. We explore the utility of oblivious power assignments, and show that essentially all such assignments result in a worst case bound of $\\Omega(n)$ slots for connectivity. This rules out a recent cla...

  1. Connecting with Your Audience.

    Science.gov (United States)

    Mamchur, Carolyn

    1989-01-01

    A workshop model on presentation skills for teachers in the classroom is presented. The goals and techniques would apply to many teaching situations in the college classroom, as well as lectures and symposium presentations. Making a personal connection, focusing on audience, and empowering the audience are discussed. (MLW)

  2. Clip, connect, clone

    DEFF Research Database (Denmark)

    Fujima, Jun; Lunzer, Aran; Hornbæk, Kasper

    2010-01-01

    using three mechanisms: clipping of input and result elements from existing applications to form cells on a spreadsheet; connecting these cells using formulas, thus enabling result transfer between applications; and cloning cells so that multiple requests can be handled side by side. We demonstrate...

  3. The connected brain

    NARCIS (Netherlands)

    van den Heuvel, M.P.

    2009-01-01

    The connected brain Martijn van den Heuvel, 2009 Our brain is a network. It is a network of different brain regions that are all functionally and structurally linked to each other. In the past decades, neuroimaging studies have provided a lot of information about the specific functions of each separ

  4. CFD modeling of pulsatile hemodynamics in the total cavopulmonary connection

    Science.gov (United States)

    Zobaer, S. M. Tareq; Hasan, A. B. M. Toufique

    2016-07-01

    Total cavopulmonary connection is a blood flow pathway which is created surgically by an operation known as Fontan procedure, performed on children with single ventricle heart defects. Recent studies have shown that the hemodynamics in the connection can be strongly influenced by the presence of pulsatile flow. The aim of this paper is model the pulsatile flow patterns, and to calculate the vorticity field and power losses in an idealized 1.5D offset model of Total Cavopulmonary Connection. A three-dimensional polyhedral mesh was constructed for the numerical simulation. The rheological properties of blood were considered as Newtonian, and flow in the connection was assumed to be laminar. The results demonstrated complex flow patterns in the connection. The outcomes of the simulation showed reasonable agreement with the results available in the literature for a similar model.

  5. Analyzing negative ties in social networks

    Directory of Open Access Journals (Sweden)

    Mankirat Kaur

    2016-03-01

    Full Text Available Online social networks are a source of sharing information and maintaining personal contacts with other people through social interactions and thus forming virtual communities online. Social networks are crowded with positive and negative relations. Positive relations are formed by support, endorsement and friendship and thus, create a network of well-connected users whereas negative relations are a result of opposition, distrust and avoidance creating disconnected networks. Due to increase in illegal activities such as masquerading, conspiring and creating fake profiles on online social networks, exploring and analyzing these negative activities becomes the need of hour. Usually negative ties are treated in same way as positive ties in many theories such as balance theory and blockmodeling analysis. But the standard concepts of social network analysis do not yield same results in respect of each tie. This paper presents a survey on analyzing negative ties in social networks through various types of network analysis techniques that are used for examining ties such as status, centrality and power measures. Due to the difference in characteristics of flow in positive and negative tie networks some of these measures are not applicable on negative ties. This paper also discusses new methods that have been developed specifically for analyzing negative ties such as negative degree, and h∗ measure along with the measures based on mixture of positive and negative ties. The different types of social network analysis approaches have been reviewed and compared to determine the best approach that can appropriately identify the negative ties in online networks. It has been analyzed that only few measures such as Degree and PN centrality are applicable for identifying outsiders in network. For applicability in online networks, the performance of PN measure needs to be verified and further, new measures should be developed based upon negative clique concept.

  6. Natural connections given by general linear and classical connections

    OpenAIRE

    Janyška, Josef

    2004-01-01

    We assume a vector bundle $p: E\\to M$ with a general linear connection $K$ and a classical linear connection $\\Lam$ on $M$. We prove that all classical linear connections on the total space $E$ naturally given by $(\\Lam, K)$ form a 15-parameter family. Further we prove that all connections on $J^1 E$ naturally given by $(\\Lam, K)$ form a 14-parameter family. Both families of connections are described geometrically.

  7. Analyzing endocrine system conservation and evolution.

    Science.gov (United States)

    Bonett, Ronald M

    2016-08-01

    Analyzing variation in rates of evolution can provide important insights into the factors that constrain trait evolution, as well as those that promote diversification. Metazoan endocrine systems exhibit apparent variation in evolutionary rates of their constituent components at multiple levels, yet relatively few studies have quantified these patterns and analyzed them in a phylogenetic context. This may be in part due to historical and current data limitations for many endocrine components and taxonomic groups. However, recent technological advancements such as high-throughput sequencing provide the opportunity to collect large-scale comparative data sets for even non-model species. Such ventures will produce a fertile data landscape for evolutionary analyses of nucleic acid and amino acid based endocrine components. Here I summarize evolutionary rate analyses that can be applied to categorical and continuous endocrine traits, and also those for nucleic acid and protein-based components. I emphasize analyses that could be used to test whether other variables (e.g., ecology, ontogenetic timing of expression, etc.) are related to patterns of rate variation and endocrine component diversification. The application of phylogenetic-based rate analyses to comparative endocrine data will greatly enhance our understanding of the factors that have shaped endocrine system evolution.

  8. Brain Oscillations and Functional Connectivity during Overt Language Production.

    Science.gov (United States)

    Ewald, Arne; Aristei, Sabrina; Nolte, Guido; Abdel Rahman, Rasha

    2012-01-01

    In the present study we investigate the communication of different large scale brain sites during an overt language production task with state of the art methods for the estimation of EEG functional connectivity. Participants performed a semantic blocking task in which objects were named in semantically homogeneous blocks of trials consisting of members of a semantic category (e.g., all objects are tools) or in heterogeneous blocks, consisting of unrelated objects. The classic pattern of slower naming times in the homogeneous relative to heterogeneous blocks is assumed to reflect the duration of lexical selection. For the collected data in the homogeneous and heterogeneous conditions the imaginary part of coherency (ImC) was evaluated at different frequencies. The ImC is a measure for detecting the coupling of different brain sites acting on sensor level. Most importantly, the ImC is robust to the artifact of volume conduction. We analyzed the ImC at all pairs of 56 EEG channels across all frequencies. Contrasting the two experimental conditions we found pronounced differences in the theta band at 7 Hz and estimated the most dominant underlying brain sources via a minimum norm inverse solution based on the ImC. As a result of the source localization, we observed connectivity between occipito-temporal and frontal areas, which are well-known to play a major role in lexical-semantic language processes. Our findings demonstrate the feasibility of investigating interactive brain activity during overt language production.

  9. On-Demand Urine Analyzer

    Science.gov (United States)

    Farquharson, Stuart; Inscore, Frank; Shende, Chetan

    2010-01-01

    A lab-on-a-chip was developed that is capable of extracting biochemical indicators from urine samples and generating their surface-enhanced Raman spectra (SERS) so that the indicators can be quantified and identified. The development was motivated by the need to monitor and assess the effects of extended weightlessness, which include space motion sickness and loss of bone and muscle mass. The results may lead to developments of effective exercise programs and drug regimes that would maintain astronaut health. The analyzer containing the lab-on-a- chip includes materials to extract 3- methylhistidine (a muscle-loss indicator) and Risedronate (a bone-loss indicator) from the urine sample and detect them at the required concentrations using a Raman analyzer. The lab-on- a-chip has both an extractive material and a SERS-active material. The analyzer could be used to monitor the onset of diseases, such as osteoporosis.

  10. Altered temporal features of intrinsic connectivity networks in boys with combined type of attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xun-Heng, E-mail: xhwang@hdu.edu.cn [College of Life Information Science and Instrument Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China); Li, Lihua [College of Life Information Science and Instrument Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China)

    2015-05-15

    Highlights: • Temporal patterns within ICNs provide new way to investigate ADHD brains. • ADHD exhibits enhanced temporal activities within and between ICNs. • Network-wise ALFF influences functional connectivity between ICNs. • Univariate patterns within ICNs are correlated to behavior scores. - Abstract: Purpose: Investigating the altered temporal features within and between intrinsic connectivity networks (ICNs) for boys with attention-deficit/hyperactivity disorder (ADHD); and analyzing the relationships between altered temporal features within ICNs and behavior scores. Materials and methods: A cohort of boys with combined type of ADHD and a cohort of age-matched healthy boys were recruited from ADHD-200 Consortium. All resting-state fMRI datasets were preprocessed and normalized into standard brain space. Using general linear regression, 20 ICNs were taken as spatial templates to analyze the time-courses of ICNs for each subject. Amplitude of low frequency fluctuations (ALFFs) were computed as univariate temporal features within ICNs. Pearson correlation coefficients and node strengths were computed as bivariate temporal features between ICNs. Additional correlation analysis was performed between temporal features of ICNs and behavior scores. Results: ADHD exhibited more activated network-wise ALFF than normal controls in attention and default mode-related network. Enhanced functional connectivities between ICNs were found in ADHD. The network-wise ALFF within ICNs might influence the functional connectivity between ICNs. The temporal pattern within posterior default mode network (pDMN) was positively correlated to inattentive scores. The subcortical network, fusiform-related DMN and attention-related networks were negatively correlated to Intelligence Quotient (IQ) scores. Conclusion: The temporal low frequency oscillations of ICNs in boys with ADHD were more activated than normal controls during resting state; the temporal features within ICNs could

  11. Variability in reef connectivity in the Coral Triangle

    Science.gov (United States)

    Thompson, D. M.; Kleypas, J. A.; Castruccio, F. S.; Watson, J. R.; Curchitser, E. N.

    2015-12-01

    The Coral Triangle (CT) is not only the global center of marine biodiversity, it also supports the livelihoods of millions of people. Unfortunately, it is also considered the most threatened of all reef regions, with rising temperature and coral bleaching already taking a toll. Reproductive connectivity between reefs plays a critical role in the reef's capacity to recover after such disturbances. Thus, oceanographic modeling efforts to understand patterns of reef connectivity are essential to the effective design of a network of Marine Protected Areas (MPAs) to conserve marine ecosystems in the Coral Triangle. Here, we combine a Regional Ocean Modeling System developed for the Coral Triangle (CT-ROMS) with a Lagrangian particle tracking tool (TRACMASS) to investigate the probability of coral larval transport between reefs. A 47-year hindcast simulation (1960-2006) was used to investigate the variability in larval transport of a broadcasting coral following mass spawning events in April and September. Potential connectivity between reefs was highly variable and stochastic from year to year, emphasizing the importance of decadal or longer simulations in identifying connectivity patterns, key source and sink regions, and thus marine management targets for MPAs. The influence of temperature on realized connectivity (future work) may add further uncertainty to year-to-year patterns of connectivity between reefs. Nonetheless, the potential connectivity results we present here suggest that although reefs in this region are primarily self-seeded, rare long-distance dispersal may promote recovery and genetic exchange between reefs in the region. The spatial pattern of "subpopulations" based solely on the physical drivers of connectivity between reefs closely match regional patterns of biodiversity, suggesting that physical barriers to larval dispersal may be a key driver of reef biodiversity. Finally, 21st Century simulations driven by the Community Earth System Model (CESM

  12. Classification of Autism Spectrum Disorder Using Supervised Learning of Brain Connectivity Measures Extracted from Synchrostates

    CERN Document Server

    Jamal, Wasifa; Oprescu, Ioana-Anastasia; Maharatna, Koushik; Apicella, Fabio; Sicca, Federico

    2014-01-01

    Objective. The paper investigates the presence of autism using the functional brain connectivity measures derived from electro-encephalogram (EEG) of children during face perception tasks. Approach. Phase synchronized patterns from 128-channel EEG signals are obtained for typical children and children with autism spectrum disorder (ASD). The phase synchronized states or synchrostates temporally switch amongst themselves as an underlying process for the completion of a particular cognitive task. We used 12 subjects in each group (ASD and typical) for analyzing their EEG while processing fearful, happy and neutral faces. The minimal and maximally occurring synchrostates for each subject are chosen for extraction of brain connectivity features, which are used for classification between these two groups of subjects. Among different supervised learning techniques, we here explored the discriminant analysis and support vector machine both with polynomial kernels for the classification task. Main results. The leave ...

  13. Analyzing the Grammar of English

    CERN Document Server

    Teschner, Richard V

    2007-01-01

    Analyzing the Grammar of English offers a descriptive analysis of the indispensable elements of English grammar. Designed to be covered in one semester, this textbook starts from scratch and takes nothing for granted beyond a reading and speaking knowledge of English. Extensively revised to function better in skills-building classes, it includes more interspersed exercises that promptly test what is taught, simplified and clarified explanations, greatly expanded and more diverse activities, and a new glossary of over 200 technical terms.Analyzing the Grammar of English is the only English gram

  14. An update on chemistry analyzers.

    Science.gov (United States)

    Vap, L M; Mitzner, B

    1996-09-01

    This update of six chemistry analyzers available to the clinician discusses several points that should be considered prior to the purchase of equipment. General topics include how to best match an instrument to clinic needs and the indirect costs associated with instrument operation. Quality assurance recommendations are discussed and common terms are defined. Specific instrument features, principles of operation, performance, and costs are presented. The information provided offers potential purchasers an objective approach to the evaluation of a chemistry analyzer for the veterinary clinic.

  15. On contravariant product conjugate connections

    Directory of Open Access Journals (Sweden)

    A. M. Blaga

    2012-02-01

    Full Text Available Invariance properties for the covariant and contravariant connections on a Riemannian manifold with respect to an almost product structure are stated. Restricting to a distribution of the contravariant connections is also discussed. The particular case of the conjugate connection is investigated and properties of the extended structural and virtual tensors for the contravariant connections are given.

  16. Left-Handed Connections.

    Science.gov (United States)

    Lipson, Alice M.

    1984-01-01

    The following aspects of left-handedness are discussed: etiology and associated learning and developmental disorders; right-brain dominance and how to detect it; adaptations to the physical learning environment; behavior patterns; and teaching techniques. (JW)

  17. Strategies for Analyzing Tone Languages

    Science.gov (United States)

    Coupe, Alexander R.

    2014-01-01

    This paper outlines a method of auditory and acoustic analysis for determining the tonemes of a language starting from scratch, drawing on the author's experience of recording and analyzing tone languages of north-east India. The methodology is applied to a preliminary analysis of tone in the Thang dialect of Khiamniungan, a virtually undocumented…

  18. The Convertible Arbitrage Strategy Analyzed

    NARCIS (Netherlands)

    Loncarski, I.; Ter Horst, J.R.; Veld, C.H.

    2006-01-01

    This paper analyzes convertible bond arbitrage on the Canadian market for the period 1998 to 2004.Convertible bond arbitrage is the combination of a long position in convertible bonds and a short position in the underlying stocks. Convertible arbitrage has been one of the most successful strategies

  19. FORTRAN Static Source Code Analyzer

    Science.gov (United States)

    Merwarth, P.

    1984-01-01

    FORTRAN Static Source Code Analyzer program, SAP (DEC VAX version), automatically gathers statistics on occurrences of statements and structures within FORTRAN program and provides reports of those statistics. Provisions made for weighting each statistic and provide an overall figure of complexity.

  20. Analyzing Classroom Instruction in Reading.

    Science.gov (United States)

    Rutherford, William L.

    A method for analyzing instructional techniques employed during reading group instruction is reported, and the characteristics of the effective reading teacher are discussed. Teaching effectiveness is divided into two categories: (1) how the teacher acts and interacts with children on a personal level and (2) how the teacher performs his…

  1. Analyzing Software Piracy in Education.

    Science.gov (United States)

    Lesisko, Lee James

    This study analyzes the controversy of software piracy in education. It begins with a real world scenario that presents the setting and context of the problem. The legalities and background of software piracy are explained and true court cases are briefly examined. Discussion then focuses on explaining why individuals and organizations pirate…

  2. Pattern matching

    OpenAIRE

    Hak, Tony; Dul, Jan

    2009-01-01

    textabstractPattern matching is comparing two patterns in order to determine whether they match (i.e., that they are the same) or do not match (i.e., that they differ). Pattern matching is the core procedure of theory-testing with cases. Testing consists of matching an “observed pattern” (a pattern of measured values) with an “expected pattern” (a hypothesis), and deciding whether these patterns match (resulting in a confirmation of the hypothesis) or do not match (resulting in a disconfirmat...

  3. An improved molecular connectivity index

    Institute of Scientific and Technical Information of China (English)

    李新华; 俞庆森; 朱龙观

    2000-01-01

    Through modification of the delta values of the molecular connectivity indexes, and connecting the quantum chemistry with topology method effectively, the molecular connectivity indexes are converted into quantum-topology indexes. The modified indexes not only keep all information obtained from the original molecular connectivity method but also have their own virtue in application, and at the same time make up some disadvantages of the quantum and molecular connectivity methods.

  4. Differences on Brain Connectivity in Adulthood Are Present in Subjects with Iron Deficiency Anemia in Infancy

    Science.gov (United States)

    Algarin, Cecilia; Karunakaran, Keerthana Deepti; Reyes, Sussanne; Morales, Cristian; Lozoff, Betsy; Peirano, Patricio; Biswal, Bharat

    2017-01-01

    Iron deficiency continues to be the most prevalent micronutrient deficit worldwide. Since iron is involved in several processes including myelination, dopamine neurotransmission and neuronal metabolism, the presence of iron deficiency anemia (IDA) in infancy relates to long-lasting neurofunctional effects. There is scarce data regarding whether these effects would extend to former iron deficient anemic human adults. Resting state functional magnetic resonance imaging (fMRI) is a novel technique to explore patterns of functional connectivity. Default Mode Network (DMN), one of the resting state networks, is deeply involved in memory, social cognition and self-referential processes. The four core regions consistently identified in the DMN are the medial prefrontal cortex, posterior cingulate/retrosplenial cortex and left and right inferior parietal cortex. Therefore to investigate the DMN in former iron deficient anemic adults is a particularly useful approach to elucidate de long term effects on functional brain. We conducted this research to explore the connection between IDA in infancy and altered patterns of resting state brain functional networks in young adults. Resting-state fMRI studies were performed to 31 participants that belong to a follow-up study since infancy. Of them, 14 participants were former iron deficient anemic in infancy and 17 were controls, with mean age of 21.5 years (±1.5) and 54.8% were males. Resting-state fMRI protocol was used and the data was analyzed using the seed based connectivity statistical analysis to assess the DMN. We found that compared to controls, former iron deficient anemic subjects showed posterior DMN decreased connectivity to the left posterior cingulate cortex (PCC), whereas they exhibited increased anterior DMN connectivity to the right PCC. Differences between groups were also apparent in the left medial frontal gyrus, with former iron deficient anemic participants having increased connectivity with areas included

  5. Patterns - "A crime solver"

    Directory of Open Access Journals (Sweden)

    A Nagasupriya

    2011-01-01

    Full Text Available Objective: This study is intended to analyze the predominant pattern of lip and finger prints in males and females and to correlate lip print and finger print for gender identity. Materials and Methods: The study sample comprised of 200 students of Vishnu Dental College, Bhimavaram, Andhra Pradesh, 100 males and 100 females aged between 18 to 27 years. Brown/pink colored lip stick was applied on the lips and the subject was asked to spread it uniformly over the lips. Lip prints were traced in the normal rest position of the lips with the help of cellophane tape. The imprint of the left thumb was taken on a white chart sheet and visualized using magnifying lens. While three main types of finger prints are identified, the classification of lip prints is simplified into branched, reticular, and vertical types. Association between lip prints and finger prints was statistically tested using Chi-square test. Results: This study showed that lip and finger patterns did not reveal statistically significant results within the gender. The correlation between lip and finger patterns for gender identification, was statistically significant. In males, branched type of lip pattern associated with arch, loop, and whorl type of finger pattern was most significant. In females, vertical lip pattern associated with arch finger pattern and reticular lip pattern associated with whorl finger patterns were most significant. Conclusion: We conclude that a correlative study between the lip print and finger print will be very useful in forensic science for gender identification.

  6. Connecting to Everyday Practices

    DEFF Research Database (Denmark)

    Iversen, Ole Sejer; Smith, Rachel Charlotte

    2012-01-01

    construction and reproduction of cultural heritage creating novel connections between self and others and between past, present and future. We present experiences from a current research project, the Digital Natives exhibition, in which social media was designed as an integral part of the exhibition to connect...... issues of digital heritage with audiences’ everyday practices in a museum. We point to the fact the use of social media in museums not only challenge us to rethink the design of technology for museum experiences. Social media also challenge us to rethink conceptions of museums and cultural heritage......We suggest that social media can contribute to reconnecting audiences’ everyday practices to issues of cultural heritage in museum institutions. Social media can support the creation of dialogical spaces in the museum, both playful and reflective, that allow audiences to engage in the ongoing...

  7. Connecting Science with Society

    DEFF Research Database (Denmark)

    awareness of the important questions of our society reflected in scientific research and of the answers produced by these research activities. The CRIS2010 conference, entitled “Bringing Science to Society”, therefore seeks to highlight the role of Current Research Information Systems for communicating......CRIS2010, the 10th conference in the bi-annual series organized by euroCRIS, focuses on the connecting role of Current Research Information Systems (CRIS). Aalborg, Denmark where CRIS2010 is held, is located near the intersection of the Northern Sea and Kattegat, a place were not only the waters...... of two seas are exchanged, but also goods and culture. In a similar way, Current Research Information Systems are at the intersection between (publicly funded) research and society. They do not only connect actors, activities and results within the research domain but also play a crucial role in raising...

  8. Weldless Flange Connections

    OpenAIRE

    Andersson, Mattias; Jonsson, Henrik; Löfqvist, Stefan; Maigne, Remi; Bravo, Unai

    2004-01-01

    This development project is a bachelor’s degree thesis work that will conclude the education program ”Development Technology” at Blekinge Institute of Technology. The development project has been done in cooperation with Faurecia Exhaust Systems AB in Torsås that constructs and manufactures manifolds, catalytic converters, mufflers and whole exhaust systems. The task with this project was to find a new solution concept for the connection of pipes into flanges in manifolds. The concept that Fa...

  9. Connecting with Citizens

    DEFF Research Database (Denmark)

    Jørgensen, Poul Erik Flyvholm; Isaksson, Maria

    2017-01-01

    /2007. If Norway, like Denmark, significantly reduces its number of municipalities, the majority of municipalities will undergo significant change and experience loss of identity. Each new municipality will need to create meaningful new identities attractive to publics fearful of alienation inside a community...... they have no relationship to. The study examines how municipalities reach out to connect with their publics, and whether they employ emotional and engaging discourse. Our data consists of 20 Norwegian and 20 Danish municipal websites....

  10. Energy storage connection system

    Science.gov (United States)

    Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

    2012-07-03

    A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

  11. Connective tissue ulcers.

    Science.gov (United States)

    Dabiri, Ganary; Falanga, Vincent

    2013-11-01

    Connective tissue disorders (CTD), which are often also termed collagen vascular diseases, include a number of related inflammatory conditions. Some of these diseases include rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis (scleroderma), localized scleroderma (morphea variants localized to the skin), Sjogren's syndrome, dermatomyositis, polymyositis, and mixed connective tissue disease. In addition to the systemic manifestations of these diseases, there are a number of cutaneous features that make these conditions recognizable on physical exam. Lower extremity ulcers and digital ulcers are an infrequent but disabling complication of long-standing connective tissue disease. The exact frequency with which these ulcers occur is not known, and the cause of the ulcerations is often multifactorial. Moreover, a challenging component of CTD ulcerations is that there are still no established guidelines for their diagnosis and treatment. The morbidity associated with these ulcerations and their underlying conditions is very substantial. Indeed, these less common but intractable ulcers represent a major medical and economic problem for patients, physicians and nurses, and even well organized multidisciplinary wound healing centers.

  12. Introduction: why analyze single cells?

    Science.gov (United States)

    Di Carlo, Dino; Tse, Henry Tat Kwong; Gossett, Daniel R

    2012-01-01

    Powerful methods in molecular biology are abundant; however, in many fields including hematology, stem cell biology, tissue engineering, and cancer biology, data from tools and assays that analyze the average signals from many cells may not yield the desired result because the cells of interest may be in the minority-their behavior masked by the majority-or because the dynamics of the populations of interest are offset in time. Accurate characterization of samples with high cellular heterogeneity may only be achieved by analyzing single cells. In this chapter, we discuss the rationale for performing analyses on individual cells in more depth, cover the fields of study in which single-cell behavior is yielding new insights into biological and clinical questions, and speculate on how single-cell analysis will be critical in the future.

  13. Methods for Analyzing Social Media

    DEFF Research Database (Denmark)

    Jensen, Jakob Linaa; [Ukendt], editors

    2013-01-01

    Social media is becoming increasingly attractive for users. It is a fast way to communicate ideas and a key source of information. It is therefore one of the most influential mediums of communication of our time and an important area for audience research. The growth of social media invites many...... new questions such as: How can we analyze social media? Can we use traditional audience research methods and apply them to online content? Which new research strategies have been developed? Which ethical research issues and controversies do we have to pay attention to? This book focuses on research...... strategies and methods for analyzing social media and will be of interest to researchers and practitioners using social media, as well as those wanting to keep up to date with the subject....

  14. Analyzing viewpoint diversity in twitter

    OpenAIRE

    2013-01-01

    Information diversity has a long tradition in human history. Recently there have been claims that diversity is diminishing in information available in social networks. On the other hand, some studies suggest that diversity is actually quite high in social networks such as Twitter. However these studies only focus on the concept of source diversity and they only focus on American users. In this paper we analyze different dimensions of diversity. We also provide an experimental design in which ...

  15. The connecting link! Lip prints and fingerprints

    Directory of Open Access Journals (Sweden)

    Amita Negi

    2016-01-01

    Full Text Available Background: Lip prints and fingerprints are considered to be unique to each individual. The study of fingerprints and lip prints is very popular in personal identification of the deceased and in criminal investigations. Aims: This study was done to find the predominant lip and fingerprint patterns in males and females in the North Indian population and also to find any correlation between lip print and fingerprint patterns within a gender. Materials and Methods: Two hundred students (100 males, 100 females were included in the study. Lip prints were recorded for each individual using a dark-colored lipstick and the right thumb impression was recorded using an ink pad. The lip prints and fingerprints were analyzed using a magnifying glass. The Chi-square test was used for statistical analysis. Results: The branched pattern in males and the vertical pattern in females were the predominant lip print patterns. The predominant fingerprint pattern in both males and females was found to be the loop pattern, followed by the whorl pattern and then the arch pattern. No statistically significant correlation was found between lip prints and fingeprints. However, the arch type of fingerprint was found to be associated with different lip print patterns in males and females. Conclusion: Lip prints and fingerprints can be used for personal identification in a forensic scenario. Further correlative studies between lip prints and fingerprints could be useful in forensic science for gender identification.

  16. Analyzing ion distributions around DNA.

    Science.gov (United States)

    Lavery, Richard; Maddocks, John H; Pasi, Marco; Zakrzewska, Krystyna

    2014-07-01

    We present a new method for analyzing ion, or molecule, distributions around helical nucleic acids and illustrate the approach by analyzing data derived from molecular dynamics simulations. The analysis is based on the use of curvilinear helicoidal coordinates and leads to highly localized ion densities compared to those obtained by simply superposing molecular dynamics snapshots in Cartesian space. The results identify highly populated and sequence-dependent regions where ions strongly interact with the nucleic and are coupled to its conformational fluctuations. The data from this approach is presented as ion populations or ion densities (in units of molarity) and can be analyzed in radial, angular and longitudinal coordinates using 1D or 2D graphics. It is also possible to regenerate 3D densities in Cartesian space. This approach makes it easy to understand and compare ion distributions and also allows the calculation of average ion populations in any desired zone surrounding a nucleic acid without requiring references to its constituent atoms. The method is illustrated using microsecond molecular dynamics simulations for two different DNA oligomers in the presence of 0.15 M potassium chloride. We discuss the results in terms of convergence, sequence-specific ion binding and coupling with DNA conformation.

  17. Remote Laser Diffraction PSD Analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Batcheller, Thomas Aquinas; Huestis, Gary Michael; Bolton, Steven Michael

    2000-06-01

    Particle size distribution (PSD) analysis of radioactive slurry samples were obtained using a modified "off-the-shelf" classical laser light scattering particle size analyzer. A Horiba Instruments Inc. Model La-300 PSD analyzer, which has a 0.1 to 600 micron measurement range, was modified for remote application in a "hot cell" (gamma radiation) environment. The general details of the modifications to this analyzer are presented in this paper. This technology provides rapid and simple PSD analysis, especially down in the fine and microscopic particle size regime. Particle size analysis of these radioactive slurries down in this smaller range was not achievable - making this technology far superior than the traditional methods used previously. Remote deployment and utilization of this technology is in an exploratory stage. The risk of malfunction in this radiation environment is countered by gaining of this tremendously useful fundamental engineering data. Successful acquisition of this data, in conjunction with other characterization analyses, provides important information that can be used in the myriad of potential radioactive waste management alternatives.

  18. Analyzing Big Data in Psychology: A Split/Analyze/Meta-Analyze Approach

    Science.gov (United States)

    Cheung, Mike W.-L.; Jak, Suzanne

    2016-01-01

    Big data is a field that has traditionally been dominated by disciplines such as computer science and business, where mainly data-driven analyses have been performed. Psychology, a discipline in which a strong emphasis is placed on behavioral theories and empirical research, has the potential to contribute greatly to the big data movement. However, one challenge to psychologists—and probably the most crucial one—is that most researchers may not have the necessary programming and computational skills to analyze big data. In this study we argue that psychologists can also conduct big data research and that, rather than trying to acquire new programming and computational skills, they should focus on their strengths, such as performing psychometric analyses and testing theories using multivariate analyses to explain phenomena. We propose a split/analyze/meta-analyze approach that allows psychologists to easily analyze big data. Two real datasets are used to demonstrate the proposed procedures in R. A new research agenda related to the analysis of big data in psychology is outlined at the end of the study. PMID:27242639

  19. Analyzing Big Data in Psychology: A Split/Analyze/Meta-Analyze Approach.

    Science.gov (United States)

    Cheung, Mike W-L; Jak, Suzanne

    2016-01-01

    Big data is a field that has traditionally been dominated by disciplines such as computer science and business, where mainly data-driven analyses have been performed. Psychology, a discipline in which a strong emphasis is placed on behavioral theories and empirical research, has the potential to contribute greatly to the big data movement. However, one challenge to psychologists-and probably the most crucial one-is that most researchers may not have the necessary programming and computational skills to analyze big data. In this study we argue that psychologists can also conduct big data research and that, rather than trying to acquire new programming and computational skills, they should focus on their strengths, such as performing psychometric analyses and testing theories using multivariate analyses to explain phenomena. We propose a split/analyze/meta-analyze approach that allows psychologists to easily analyze big data. Two real datasets are used to demonstrate the proposed procedures in R. A new research agenda related to the analysis of big data in psychology is outlined at the end of the study.

  20. Analyzing Big Data in Psychology: A Split/Analyze/Meta-Analyze Approach

    Directory of Open Access Journals (Sweden)

    Mike W.-L. Cheung

    2016-05-01

    Full Text Available Big data is a field that has traditionally been dominated by disciplines such as computer science and business, where mainly data-driven analyses have been performed. Psychology, a discipline in which a strong emphasis is placed on behavioral theories and empirical research, has the potential to contribute greatly to the big data movement. However, one challenge to psychologists – and probably the most crucial one – is that most researchers may not have the necessary programming and computational skills to analyze big data. In this study we argue that psychologists can also conduct big data research and that, rather than trying to acquire new programming and computational skills, they should focus on their strengths, such as performing psychometric analyses and testing theories using multivariate analyses to explain phenomena. We propose a split/analyze/meta-analyze approach that allows psychologists to easily analyze big data. Two real datasets are used to demonstrate the proposed procedures in R. A new research agenda related to the analysis of big data in psychology is outlined at the end of the study.

  1. The aesthetic of dragon pattern elements in modern clothing

    Institute of Scientific and Technical Information of China (English)

    任倩慧

    2015-01-01

    Dragon pattern with a long history of traditional patterns,contains profound cultural connotation.This passage illustrate the aesthetic analysis of dragon pattern in modern clothing, analyze the aesthetic expression of dragon pattern with modern costume designer.

  2. Limited genetic connectivity of Pavona gigantea in the Mexican Pacific

    Science.gov (United States)

    Saavedra-Sotelo, N. C.; Calderon-Aguilera, L. E.; Reyes-Bonilla, H.; López-Pérez, R. A.; Medina-Rosas, P.; Rocha-Olivares, A.

    2011-09-01

    Coral reefs are the most complex and diverse of aquatic ecosystems. Their vulnerability and deterioration in the face of anthropogenic disturbance require the adoption of conservation and restoration efforts to maintain their resilience, for which connectivity is of paramount importance. Dispersal of meroplanktonic larval stages drives the levels of connectivity among coral populations and is influenced by the local current regime, the synchronization of spawning events, and the capacity of larvae to reach recruitment sites. This research aims to quantify the levels of connectivity among Pavona gigantea populations in the Mexican Pacific, using two mitochondrial genes and a nuclear gene. Mitochondrial genes were insufficiently variable to test geographical heterogeneity, whereas the more variable ( h ≥ 0.86) nuclear rDNA indicated significant geographic differentiation ( Φ ST = 0.159, P moderate and unidirectional gene flow from Huatulco Bays to La Paz Bay and Marietas Islands. We found partial agreement between the patterns of connectivity among localities and the general pattern of superficial oceanographic circulation of the region, particularly in reference with the expected influence of the northward flowing West Mexican Current. These results suggest a limited demographic connectivity among Pavona gigantea populations along the Mexican Pacific, mediated by passive larval transport, and highlight the difficulty of predicting connectivity patterns on the basis of highly variable oceanographic regimes and reproductive events. The limited connectivity is of consequence for the viability and vulnerability of local populations and should be considered in the management and conservation strategies in the region.

  3. Connective Versus Collective Action in Social Movements

    DEFF Research Database (Denmark)

    Lundgaard, Daniel; Razmerita, Liana

    ). This process is influenced by two dynamics; the logic of collective action and the logic of connective action (Bennett & Segerberg, 2012). The logic of collective action is defined by formal organizational control, stronger commitment and collective identity framing (Bennett & Segerberg 2012). The logic...... of connective action is are sult of mediating technologies especially web 2.0 that inspire and affords emergent digitally networked action, based on large‐scale self‐organized, fluid and weak‐tied networks (Ibid.). These logics are investigated in three different social media movements; #YesAllWomen, #Black......LivesMatter and the #IceBucketChallenge by analyzing Twitter and Facebook data from key periods of these movements,through a net nographic study. In particular, this study has investigated the following research questions: How are the logics of collective and connective action reflected in online social media interactions...

  4. Economy, energy and environment - Methods to analyze connections; Ekonomi, energi och miljoe - metoder att analysera samband

    Energy Technology Data Exchange (ETDEWEB)

    Ahlroth, Sofia; Finnveden, Goeran; Hochschorner Elisabeth [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Industrial Ecology; Ekvall, Thomas [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Systems Technology; Wadeskog, Anders; Palm, Viveka [Statistics Sweden, Stockholm (Sweden). Environmental Accounts

    2003-12-01

    This report gives a review of instruments that can be used for finding economic, structural and environmental effects of decisions in the environmental area, and describe what is possible to achieve, economically and technically. Twelve different aspects are used for characterizing the instruments. Applications and limitations of the instruments are discussed. For many instruments there exists a lively discussion on their weaknesses and limitations. We focus on system analytical instruments, i.e. environment-economic methods, energy and energy-economic modelling and environment-system-analytical tools In the economic area we discuss I/O-analyses, CGE-models and econometric models as well as a few descriptive analytica tools: Cost-benefit analysis, CBA and Life Cycle Analyses.

  5. Pattern recognition

    CERN Document Server

    Theodoridis, Sergios

    2003-01-01

    Pattern recognition is a scientific discipline that is becoming increasingly important in the age of automation and information handling and retrieval. Patter Recognition, 2e covers the entire spectrum of pattern recognition applications, from image analysis to speech recognition and communications. This book presents cutting-edge material on neural networks, - a set of linked microprocessors that can form associations and uses pattern recognition to ""learn"" -and enhances student motivation by approaching pattern recognition from the designer's point of view. A direct result of more than 10

  6. The Aqueduct Global Flood Analyzer

    Science.gov (United States)

    Iceland, Charles

    2015-04-01

    As population growth and economic growth take place, and as climate change accelerates, many regions across the globe are finding themselves increasingly vulnerable to flooding. A recent OECD study of the exposure of the world's large port cities to coastal flooding found that 40 million people were exposed to a 1 in 100 year coastal flood event in 2005, and the total value of exposed assets was about US 3,000 billion, or 5% of global GDP. By the 2070s, those numbers were estimated to increase to 150 million people and US 35,000 billion, or roughly 9% of projected global GDP. Impoverished people in developing countries are particularly at risk because they often live in flood-prone areas and lack the resources to respond. WRI and its Dutch partners - Deltares, IVM-VU University Amsterdam, Utrecht University, and PBL Netherlands Environmental Assessment Agency - are in the initial stages of developing a robust set of river flood and coastal storm surge risk measures that show the extent of flooding under a variety of scenarios (both current and future), together with the projected human and economic impacts of these flood scenarios. These flood risk data and information will be accessible via an online, easy-to-use Aqueduct Global Flood Analyzer. We will also investigate the viability, benefits, and costs of a wide array of flood risk reduction measures that could be implemented in a variety of geographic and socio-economic settings. Together, the activities we propose have the potential for saving hundreds of thousands of lives and strengthening the resiliency and security of many millions more, especially those who are most vulnerable. Mr. Iceland will present Version 1.0 of the Aqueduct Global Flood Analyzer and provide a preview of additional elements of the Analyzer to be released in the coming years.

  7. Method for analyzing microbial communities

    Science.gov (United States)

    Zhou, Jizhong [Oak Ridge, TN; Wu, Liyou [Oak Ridge, TN

    2010-07-20

    The present invention provides a method for quantitatively analyzing microbial genes, species, or strains in a sample that contains at least two species or strains of microorganisms. The method involves using an isothermal DNA polymerase to randomly and representatively amplify genomic DNA of the microorganisms in the sample, hybridizing the resultant polynucleotide amplification product to a polynucleotide microarray that can differentiate different genes, species, or strains of microorganisms of interest, and measuring hybridization signals on the microarray to quantify the genes, species, or strains of interest.

  8. Blood stain pattern analysis.

    Science.gov (United States)

    Peschel, O; Kunz, S N; Rothschild, M A; Mützel, E

    2011-09-01

    Bloodstain pattern analysis (BPA) refers to the collection, categorization and interpretation of the shape and distribution of bloodstains connected with a crime. These kinds of stains occur in a considerable proportion of homicide cases. They offer extensive information and are an important part of a functional, medically and scientifically based reconstruction of a crime. The following groups of patterns can essentially be distinguished: dripped and splashed blood, projected blood, impact patterns, cast-off stains, expirated and transferred bloodstains. A highly qualified analysis can help to estimate facts concerning the location, quality and intensity of an external force. A sequence of events may be recognized, and detailed questions connected with the reconstruction of the crime might be answered. In some cases, BPA helps to distinguish between accident, homicide and suicide or to identify bloodstains originating from a perpetrator. BPA is based on systematic training, a visit to the crime scene or alternatively good photographic documentation, and an understanding and knowledge of autopsy findings or statements made by the perpetrator and/or victim. A BPA working group has been established within the German Society of Legal Medicine aiming to put the knowledge and practical applications of this subdiscipline of forensic science on a wider basis.

  9. Information Model for Connection Management in Automatic Switched Optical Network

    Institute of Scientific and Technical Information of China (English)

    Xu Yunbin(徐云斌); Song Hongsheng; Gui Xuan; Zhang Jie; Gu Wanyi

    2004-01-01

    The three types of connections (Permanent Connection, Soft Permanent Connection and Switched Connection) provided by ASON can adapt the requirement of different network services. Management and maintenance of these three connections are the most important aspect of ASON management. The information models proposed in this paper are used for the purpose of ASON connection management. Firstly a new information model is proposed to meet the requirement for the control plane introduced by ASON. In this model, a new class ControlNE is given, and the relationship between the ControlNE and the transport NE (network element) is also defined. Then this paper proposes information models for the three types of connections for the first time, and analyzes the relationship between the three kinds of connections and the basic network transport entities. Finally, the paper defines some CORBA interfaces for the management of the three connections. In these interfaces, some operations such as create or release a connection are defined, and some other operations can manage the performance of the three kinds of connections, which is necessary for a distributed management system.

  10. Thermal and evolved gas analyzer

    Science.gov (United States)

    Williams, M. S.; Boynton, W. V.; James, R. L.; Verts, W. T.; Bailey, S. H.; Hamara, D. K.

    1998-01-01

    The Thermal and Evolved Gas Analyzer (TEGA) instrument will perform calorimetry and evolved gas analysis on soil samples collected from the Martian surface. TEGA is one of three instruments, along with a robotic arm, that form the Mars Volatile and Climate Survey (MVACS) payload. The other instruments are a stereo surface imager, built by Peter Smith of the University of Arizona and a meteorological station, built by JPL. The MVACS lander will investigate a Martian landing site at approximately 70 deg south latitude. Launch will take place from Kennedy Space Center in January, 1999. The TEGA project started in February, 1996. In the intervening 24 months, a flight instrument concept has been designed, prototyped, built as an engineering model and flight model, and tested. The instrument performs laboratory-quality differential-scanning calorimetry (DSC) over the temperature range of Mars ambient to 1400K. Low-temperature volatiles (water and carbon dioxide ices) and the carbonates will be analyzed in this temperature range. Carbonates melt and evolve carbon dioxide at temperatures above 600 C. Evolved oxygen (down to a concentration of 1 ppm) is detected, and C02 and water vapor and the isotopic variations of C02 and water vapor are detected and their concentrations measured. The isotopic composition provides important tests of the theory of solar system formation.

  11. VOSA: A VO SED Analyzer

    Science.gov (United States)

    Rodrigo, C.; Bayo, A.; Solano, E.

    2017-03-01

    VOSA (VO Sed Analyzer, http://svo2.cab.inta-csic.es/theory/vosa) is a public web-tool developed by the Spanish Virtual Observatory (http://svo.cab.inta-csic.es/) and designed to help users to (1) build Spectral Energy Distributions (SEDs) combining private photometric measurements with data available in VO services, (2) obtain relevant properties of these objects (distance, extinction, etc) from VO catalogs, (3) analyze them comparing observed photometry with synthetic photometry from different collections of theoretical models or observational templates, using different techniques (chi-square minimization, Bayesian analysis) to estimate physical parameters of the observed objects (teff, logg, metallicity, stellar radius/distance ratio, infrared excess, etc), and use these results to (4) estimate masses and ages via interpolation of collections of isochrones and evolutionary tracks from the VO. In particular, VOSA offers the advantage of deriving physical parameters using all the available photometric information instead of a restricted subset of colors. The results can be downloaded in different formats or sent to other VO tools using SAMP. We have upgraded VOSA to provide access to Gaia photometry and give a homogeneous estimation of the physical parameters of thousands of objects at a time. This upgrade has required the implementation of a new computation paradigm, including a distributed environment, the capability of submitting and processing jobs in an asynchronous way, the use of parallelized computing to speed up processes (˜ ten times faster) and a new design of the web interface.

  12. Connecting the Production Multiple

    DEFF Research Database (Denmark)

    Lichen, Alex Yu; Mouritsen, Jan

    was implementing sales and operations planning (S&OP) process to foster integration on its demand chain. Although actors wanted to see what it is to produce, that is to say, the object Production, as a singular object that could be diffused across time and space, Production became more multiple because the S...... in opposite directions. They are all part of the fluid object. There is no single chain of circulating references that makes the object a matter of fact. Accounting fluidity means that references drift back and forth and enact new realities also connected to the chain. In this setting future research may...

  13. Transcultural Tectonic Connections

    DEFF Research Database (Denmark)

    Carter, Adrian

    2014-01-01

    This paper presents an understanding of Jørn Utzon, as one of the most profound exponents of a transcultural and tectonic approach to modern architecture in the late twentieth century. The paper will examine the sources of inspiration, intersections and connections in Utzon’s architecture; which...... ruins in Mexico. The Sydney Opera House’s signature sail-like roof shells derive from knowledge of boat building in his youth and ancient Chinese and Japanese temple roofs floating above a stone base. With the choice of ceramic tiles to accentuate the sculptural character of the shells, owing its...

  14. Naturally Connecting the World

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ During China International Trade Fair for Home Textiles and Accessories held in Shanghai 2010(on Aug.25th the second day of the fair),Cotton Council International(CCI)hosted an exchange meeting targeted the COTTON USATM home textile licenses,taking"Naturally Connecting the World-Opportunities for Sourcing and Collaboration with Cotton-Made Home Textiles"as the theme of the meeting.CCI's representative institution in China invited the domestic famous home textile brands,enterprises and their customers to participate in the exchange which aims to introduce the current development trend of the global cotton textile industry through CCI,the powerful platform of communication.

  15. Practicing (Dis)connections

    DEFF Research Database (Denmark)

    day-to-day character of the work practices entailed, tracing their at once embedded, yet, distributed and disparate – (dis)connected – configurations. In the course of an MRI exam, from the screening of the patient to the scanning itself, and onto the subsequent processing and analysis of the images...... and redistribution of knowledge-practices in and through sociotechnical change, particularly in the light of the advent of film-less radiology, and how MRI comes to be particularly implicated in the transition/development in radiology toward practices entailing picture archive and communication systems (PACS...

  16. No Reef Is an Island: Integrating Coral Reef Connectivity Data into the Design of Regional-Scale Marine Protected Area Networks.

    Directory of Open Access Journals (Sweden)

    Steven R Schill

    Full Text Available We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008-2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, a conservation planning software tool, to identify a regional coral reef MPA network design that meets conservation goals, minimizes underlying threats, and maintains coral reef connectivity. Our results suggest that approximately 77% of coral reefs identified as having a high regional connectivity value are not included in the existing MPA network. This research is unique because we quantify and report coral larval connectivity data by marine ecoregions and Exclusive Economic Zones (EZZ and use this information to identify gaps in the current Caribbean-wide MPA network by integrating asymmetric connectivity information in Marxan to design a regional MPA network that includes important reef network connections. The identification of important reef connectivity metrics guides the selection of priority conservation areas and supports resilience at the whole system level into the future.

  17. No Reef Is an Island: Integrating Coral Reef Connectivity Data into the Design of Regional-Scale Marine Protected Area Networks.

    Science.gov (United States)

    Schill, Steven R; Raber, George T; Roberts, Jason J; Treml, Eric A; Brenner, Jorge; Halpin, Patrick N

    2015-01-01

    We integrated coral reef connectivity data for the Caribbean and Gulf of Mexico into a conservation decision-making framework for designing a regional scale marine protected area (MPA) network that provides insight into ecological and political contexts. We used an ocean circulation model and regional coral reef data to simulate eight spawning events from 2008-2011, applying a maximum 30-day pelagic larval duration and 20% mortality rate. Coral larval dispersal patterns were analyzed between coral reefs across jurisdictional marine zones to identify spatial relationships between larval sources and destinations within countries and territories across the region. We applied our results in Marxan, a conservation planning software tool, to identify a regional coral reef MPA network design that meets conservation goals, minimizes underlying threats, and maintains coral reef connectivity. Our results suggest that approximately 77% of coral reefs identified as having a high regional connectivity value are not included in the existing MPA network. This research is unique because we quantify and report coral larval connectivity data by marine ecoregions and Exclusive Economic Zones (EZZ) and use this information to identify gaps in the current Caribbean-wide MPA network by integrating asymmetric connectivity information in Marxan to design a regional MPA network that includes important reef network connections. The identification of important reef connectivity metrics guides the selection of priority conservation areas and supports resilience at the whole system level into the future.

  18. Loss Strategies for Competing TCP/IP Connections

    OpenAIRE

    Altman, Eitan; El-Azouzi, Rachid; Ros, David; Tuffin, Bruno

    2004-01-01

    We study in this paper two competing TCP connections that share a common bottleneck link. When congestion occurs, one (or both) connections will suffer a loss that will cause its throughput to decrease by a multiplicative factor. The identity of the connection that will suffer a loss is determined by a randomized «loss strategy» that may depend on the throughputs of the connections at the congestion instant. We analyze several loss strategies: the one in which the identity of loss is independ...

  19. k-Connectivity of Random Key Graphs

    CERN Document Server

    Zhao, Jun; Gligor, Virgil

    2015-01-01

    Random key graphs represent topologies of secure wireless sensor networks that apply the seminal Eschenauer-Gligor random key predistribution scheme to secure communication between sensors. These graphs have received much attention and also been used in diverse application areas beyond secure sensor networks; e.g., cryptanalysis, social networks, and recommender systems. Formally, a random key graph with $n$ nodes is constructed by assigning each node $X_n$ keys selected uniformly at random from a pool of $Y_n$ keys and then putting an undirected edge between any two nodes sharing at least one key. Considerable progress has been made in the literature to analyze connectivity and $k$-connectivity of random key graphs, where $k$-connectivity of a graph ensures connectivity even after the removal of $k$ nodes or $k$ edges. Yet, it still remains an open question for $k$-connectivity in random key graphs under $X_n \\geq 2$ and $X_n = o(\\sqrt{\\ln n})$ (the case of $X_n=1$ is trivial). In this paper, we answer the a...

  20. VoIP Forensic Analyzer

    Directory of Open Access Journals (Sweden)

    M Mohemmed Sha

    2016-01-01

    Full Text Available People have been utilizing Voice over Internet Protocol (VoIP in most of the conventional communication facilities which has been of assistance in the enormous attenuation of operating costs, as well as the promotion of next- generation communication services-based IP. As an intimidating upshot, cyber criminals have correspondingly started interjecting the environment and creating new challenges for the law enforcement system in any Country. This paper presents an idea of a framework for the forensic analysis of the VoIP traffic over the network. This forensic activity includes spotting and scrutinizing the network patterns of VoIP-SIP stream, which is used to initiate a session for the communication, and regenerate the content from VoIP-RTP stream, which is employed to convey the data. Proposed network forensic investigation framework also accentuates on developing an efficient packet restructuring algorithm for tracing the depraved users involved in a conversation. Network forensics is the basis of proposed work, and performs packet level surveillance of VoIP followed by reconstruction of original malicious content or network session between users for their prosecution in the court.

  1. Foam patterns

    Science.gov (United States)

    Chaudhry, Anil R; Dzugan, Robert; Harrington, Richard M; Neece, Faurice D; Singh, Nipendra P; Westendorf, Travis

    2013-11-26

    A method of creating a foam pattern comprises mixing a polyol component and an isocyanate component to form a liquid mixture. The method further comprises placing a temporary core having a shape corresponding to a desired internal feature in a cavity of a mold and inserting the mixture into the cavity of the mold so that the mixture surrounds a portion of the temporary core. The method optionally further comprises using supporting pins made of foam to support the core in the mold cavity, with such pins becoming integral part of the pattern material simplifying subsequent processing. The method further comprises waiting for a predetermined time sufficient for a reaction from the mixture to form a foam pattern structure corresponding to the cavity of the mold, wherein the foam pattern structure encloses a portion of the temporary core and removing the temporary core from the pattern independent of chemical leaching.

  2. Geodesic patterns

    KAUST Repository

    Pottmann, Helmut

    2010-07-26

    Geodesic curves in surfaces are not only minimizers of distance, but they are also the curves of zero geodesic (sideways) curvature. It turns out that this property makes patterns of geodesics the basic geometric entity when dealing with the cladding of a freeform surface with wooden panels which do not bend sideways. Likewise a geodesic is the favored shape of timber support elements in freeform architecture, for reasons of manufacturing and statics. Both problem areas are fundamental in freeform architecture, but so far only experimental solutions have been available. This paper provides a systematic treatment and shows how to design geodesic patterns in different ways: The evolution of geodesic curves is good for local studies and simple patterns; the level set formulation can deal with the global layout of multiple patterns of geodesics; finally geodesic vector fields allow us to interactively model geodesic patterns and perform surface segmentation into panelizable parts. © 2010 ACM.

  3. Coaxial charged particle energy analyzer

    Science.gov (United States)

    Kelly, Michael A. (Inventor); Bryson, III, Charles E. (Inventor); Wu, Warren (Inventor)

    2011-01-01

    A non-dispersive electrostatic energy analyzer for electrons and other charged particles having a generally coaxial structure of a sequentially arranged sections of an electrostatic lens to focus the beam through an iris and preferably including an ellipsoidally shaped input grid for collimating a wide acceptance beam from a charged-particle source, an electrostatic high-pass filter including a planar exit grid, and an electrostatic low-pass filter. The low-pass filter is configured to reflect low-energy particles back towards a charged particle detector located within the low-pass filter. Each section comprises multiple tubular or conical electrodes arranged about the central axis. The voltages on the lens are scanned to place a selected energy band of the accepted beam at a selected energy at the iris. Voltages on the high-pass and low-pass filters remain substantially fixed during the scan.

  4. Compact Microwave Fourier Spectrum Analyzer

    Science.gov (United States)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry

    2009-01-01

    A compact photonic microwave Fourier spectrum analyzer [a Fourier-transform microwave spectrometer, (FTMWS)] with no moving parts has been proposed for use in remote sensing of weak, natural microwave emissions from the surfaces and atmospheres of planets to enable remote analysis and determination of chemical composition and abundances of critical molecular constituents in space. The instrument is based on a Bessel beam (light modes with non-zero angular momenta) fiber-optic elements. It features low power consumption, low mass, and high resolution, without a need for any cryogenics, beyond what is achievable by the current state-of-the-art in space instruments. The instrument can also be used in a wide-band scatterometer mode in active radar systems.

  5. LHCb connects its pipes

    CERN Multimedia

    2006-01-01

    Two weeks ago the first beryllium section of the LHCb beam vacuum chamber was installed. This three-day operation, after requiring lengthy preparation work, demanded patience and precision as the first of four sections of the beampipe was connected to the vertex locator (VeLo) vacuum vessel. The AT-VAC Group with the collaboration of PH/LBD, including Gloria Corti, Tatsuya Nakada, Patrice Mermet, Delios Ramos, Frans Mul, Bruno Versollato, Bernard Corajod, and Raymond Veness. (Not pictured: Adriana Rossi and Laurent Bouvet) This first installed section is composed of a nearly two-metre long conical tube of one-millimetre thick beryllium and of a thin spherical-shaped window, 800 millimeter diameter, made of an aluminum alloy, and has the appearance of a mushroom lying on its side. The window is connected to the conical part of the beampipe through an aluminum alloy bellow, which is needed to allow for mechanical alignment once the assembly is installed. Beryllium was chosen as the material for 12 m of the 19...

  6. Analyzing planar cell polarity during zebrafish gastrulation.

    Science.gov (United States)

    Jessen, Jason R

    2012-01-01

    Planar cell polarity was first described in invertebrates over 20 years ago and is defined as the polarity of cells (and cell structures) within the plane of a tissue, such as an epithelium. Studies in the last 10 years have identified critical roles for vertebrate homologs of these planar cell polarity proteins during gastrulation cell movements. In zebrafish, the terms convergence and extension are used to describe the collection of morphogenetic movements and cell behaviors that contribute to narrowing and elongation of the embryonic body plan. Disruption of planar cell polarity gene function causes profound defects in convergence and extension creating an embryo that has a shortened anterior-posterior axis and is broadened mediolaterally. The zebrafish gastrula-stage embryo is transparent and amenable to live imaging using both Nomarski/differential interference contrast and fluorescence microscopy. This chapter describes methods to analyze convergence and extension movements at the cellular level and thereby connect embryonic phenotypes with underlying planar cell polarity defects in migrating cells.

  7. Connecting multimodality in human communication.

    Science.gov (United States)

    Regenbogen, Christina; Habel, Ute; Kellermann, Thilo

    2013-01-01

    A successful reciprocal evaluation of social signals serves as a prerequisite for social coherence and empathy. In a previous fMRI study we studied naturalistic communication situations by presenting video clips to our participants and recording their behavioral responses regarding empathy and its components. In two conditions, all three channels transported congruent emotional or neutral information, respectively. Three conditions selectively presented two emotional channels and one neutral channel and were thus bimodally emotional. We reported channel-specific emotional contributions in modality-related areas, elicited by dynamic video clips with varying combinations of emotionality in facial expressions, prosody, and speech content. However, to better understand the underlying mechanisms accompanying a naturalistically displayed human social interaction in some key regions that presumably serve as specific processing hubs for facial expressions, prosody, and speech content, we pursued a reanalysis of the data. Here, we focused on two different descriptions of temporal characteristics within these three modality-related regions [right fusiform gyrus (FFG), left auditory cortex (AC), left angular gyrus (AG) and left dorsomedial prefrontal cortex (dmPFC)]. By means of a finite impulse response (FIR) analysis within each of the three regions we examined the post-stimulus time-courses as a description of the temporal characteristics of the BOLD response during the video clips. Second, effective connectivity between these areas and the left dmPFC was analyzed using dynamic causal modeling (DCM) in order to describe condition-related modulatory influences on the coupling between these regions. The FIR analysis showed initially diminished activation in bimodally emotional conditions but stronger activation than that observed in neutral videos toward the end of the stimuli, possibly by bottom-up processes in order to compensate for a lack of emotional information. The

  8. [Pulmonary involvement in connective tissue disease].

    Science.gov (United States)

    Bartosiewicz, Małgorzata

    2016-01-01

    The connective tissue diseases are a variable group of autoimmune mediated disorders characterized by multiorgan damage. Pulmonary complications are common, usually occur after the onset of joint symptoms, but can also be initially presenting complaint. The respiratory system may be involved in all its component: airways, vessels, parenchyma, pleura and respiratory muscles. Lung involvement is an increasing cause of morbidity and mortality in the connective tissue diseases. Clinical course is highly variable - can range from mild to rapidly progressive, some processes are reversible, while others are irreversible. Thus, the identification of reversible disease , and separately progressive disease, are important clinical issues. The frequency, clinical presentation, prognosis and responce to therapy are different, depending on the pattern of involvement as well as on specyfic diagnostic method used to identify it. High- resolution computed tompography plays an important role in identifying patients with respiratory involvement. Pulmonary function tests are a sensitive tool detecting interstitial lung disease. In this article, pulmonary lung involvement accompanying most frequently apperaing connective tissue diseases - rheumatoid arthritis, systemic sclerosis, lupus erythematosus, polymyositis/dermatomyositis, Sjögrens syndrome and mixed connective tissue disaese are reviewed.

  9. Structural connectivity asymmetry in the neonatal brain.

    Science.gov (United States)

    Ratnarajah, Nagulan; Rifkin-Graboi, Anne; Fortier, Marielle V; Chong, Yap Seng; Kwek, Kenneth; Saw, Seang-Mei; Godfrey, Keith M; Gluckman, Peter D; Meaney, Michael J; Qiu, Anqi

    2013-07-15

    Asymmetry of the neonatal brain is not yet understood at the level of structural connectivity. We utilized DTI deterministic tractography and structural network analysis based on graph theory to determine the pattern of structural connectivity asymmetry in 124 normal neonates. We tracted white matter axonal pathways characterizing interregional connections among brain regions and inferred asymmetry in left and right anatomical network properties. Our findings revealed that in neonates, small-world characteristics were exhibited, but did not differ between the two hemispheres, suggesting that neighboring brain regions connect tightly with each other, and that one region is only a few paths away from any other region within each hemisphere. Moreover, the neonatal brain showed greater structural efficiency in the left hemisphere than that in the right. In neonates, brain regions involved in motor, language, and memory functions play crucial roles in efficient communication in the left hemisphere, while brain regions involved in emotional processes play crucial roles in efficient communication in the right hemisphere. These findings suggest that even at birth, the topology of each cerebral hemisphere is organized in an efficient and compact manner that maps onto asymmetric functional specializations seen in adults, implying lateralized brain functions in infancy.

  10. Climate change and coral reef connectivity

    Science.gov (United States)

    Munday, P. L.; Leis, J. M.; Lough, J. M.; Paris, C. B.; Kingsford, M. J.; Berumen, M. L.; Lambrechts, J.

    2009-06-01

    This review assesses and predicts the impacts that rapid climate change will have on population connectivity in coral reef ecosystems, using fishes as a model group. Increased ocean temperatures are expected to accelerate larval development, potentially leading to reduced pelagic durations and earlier reef-seeking behaviour. Depending on the spatial arrangement of reefs, the expectation would be a reduction in dispersal distances and the spatial scale of connectivity. Small increase in temperature might enhance the number of larvae surviving the pelagic phase, but larger increases are likely to reduce reproductive output and increase larval mortality. Changes to ocean currents could alter the dynamics of larval supply and changes to planktonic productivity could affect how many larvae survive the pelagic stage and their condition at settlement; however, these patterns are likely to vary greatly from place-to-place and projections of how oceanographic features will change in the future lack sufficient certainty and resolution to make robust predictions. Connectivity could also be compromised by the increased fragmentation of reef habitat due to the effects of coral bleaching and ocean acidification. Changes to the spatial and temporal scales of connectivity have implications for the management of coral reef ecosystems, especially the design and placement of marine-protected areas. The size and spacing of protected areas may need to be strategically adjusted if reserve networks are to retain their efficacy in the future.

  11. Learning probabilistic models of connectivity from multiple spike train data

    OpenAIRE

    2010-01-01

    Neuronal circuits or cell assemblies carry out brain function through complex coordinated firing patterns [1]. Inferring topology of neuronal circuits from simultaneously recorded spike train data is a challenging problem in neuroscience. In this work we present a new class of dynamic Bayesian networks to infer polysynaptic excitatory connectivity between spiking cortical neurons [2]. The emphasis on excitatory networks allows us to learn connectivity models by exploiting fast data mining alg...

  12. Effects of auxiliary source connections in multichip power module

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Beczkowski, Szymon

    2016-01-01

    totally decouple the power loop and the gate loop like how the Kelvin source connection does, because they are still in the loop of power source current. Three effects of the auxiliary source connection are investigated and analyzed: common source stray inductance reduction, transient drain-source current......Auxiliary source bond wires and connections are widely used to in the power module with paralleled MOSFETs or IGBTs. This paper investigates the working mechanism and the effects of the auxiliary source connections in multichip power modules. It reveals that the auxiliary source connections cannot...... imbalance mitigation and influence on the steady state bond wire current distribution. Simulation and experimental results validate the working mechanism analysis and the effects of the auxiliary source connections....

  13. Search Patterns

    CERN Document Server

    Morville, Peter

    2010-01-01

    What people are saying about Search Patterns "Search Patterns is a delight to read -- very thoughtful and thought provoking. It's the most comprehensive survey of designing effective search experiences I've seen." --Irene Au, Director of User Experience, Google "I love this book! Thanks to Peter and Jeffery, I now know that search (yes, boring old yucky who cares search) is one of the coolest ways around of looking at the world." --Dan Roam, author, The Back of the Napkin (Portfolio Hardcover) "Search Patterns is a playful guide to the practical concerns of search interface design. It cont

  14. Thomson parabola ion energy analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Cobble, James A [Los Alamos National Laboratory; Flippo, Kirk A [Los Alamos National Laboratory; Letzring, Samuel A [Los Alamos National Laboratory; Lopez, Frank E [Los Alamos National Laboratory; Offermann, Dustin T [Los Alamos National Laboratory; Oertel, John A [Los Alamos National Laboratory; Mastrosimone, Dino [UNIV OF ROCHESTER

    2010-01-01

    A new, versatile Thomson parabola ion energy (TPIE) analyzer has been designed and constructed for use at the OMEGA-EP facility. Multi-MeV ions from EP targets are transmitted through a W pinhole into a (5- or 8-kG) magnetic field and subsequently through a parallel electric field of up to 30 kV/cm. The ion drift region may have a user-selected length of 10, 50, or 80 cm. With the highest fields, 500-Me V C{sup 6+} and C{sup 5+} may be resolved. TPIE is TIM-mounted at OMEGA-EP and is qualified in all existing TIMs. The instrument runs on pressure-interlocked 15-VDC power available in EP TIM carts. It may be inserted to within several inches of the target to attain sufficient flux for a measurement. For additional flux control, the user may select a square-aperture W pinhole of 0.004-inch or 0.010-inch. The detector consists of CR-39 backed by an image plate. The fully relativistic design code and design features are discussed. Ion spectral results from first use at OMEGA-EP are expected.

  15. Transnational Connections and Multiple Belongings

    DEFF Research Database (Denmark)

    Galal, Lise Paulsen; Sparre, Sara Cathrine Lei

    With the purpose of presenting DIMECCE key findings, we in this paper present different aspects, potentials and challenges related to the Middle Eastern Christians transnational connections and multiple belonging. We distinguish between individual transnational connections and practices, such as ......, such as family relations, churches as transnational – or global – institutions, and other organisations and associations established to support politically, socially or culturally connections and development in the country or region of origin.......With the purpose of presenting DIMECCE key findings, we in this paper present different aspects, potentials and challenges related to the Middle Eastern Christians transnational connections and multiple belonging. We distinguish between individual transnational connections and practices...

  16. Zebrafish Expression Ontology of Gene Sets (ZEOGS): a tool to analyze enrichment of zebrafish anatomical terms in large gene sets.

    Science.gov (United States)

    Prykhozhij, Sergey V; Marsico, Annalisa; Meijsing, Sebastiaan H

    2013-09-01

    The zebrafish (Danio rerio) is an established model organism for developmental and biomedical research. It is frequently used for high-throughput functional genomics experiments, such as genome-wide gene expression measurements, to systematically analyze molecular mechanisms. However, the use of whole embryos or larvae in such experiments leads to a loss of the spatial information. To address this problem, we have developed a tool called Zebrafish Expression Ontology of Gene Sets (ZEOGS) to assess the enrichment of anatomical terms in large gene sets. ZEOGS uses gene expression pattern data from several sources: first, in situ hybridization experiments from the Zebrafish Model Organism Database (ZFIN); second, it uses the Zebrafish Anatomical Ontology, a controlled vocabulary that describes connected anatomical structures; and third, the available connections between expression patterns and anatomical terms contained in ZFIN. Upon input of a gene set, ZEOGS determines which anatomical structures are overrepresented in the input gene set. ZEOGS allows one for the first time to look at groups of genes and to describe them in terms of shared anatomical structures. To establish ZEOGS, we first tested it on random gene selections and on two public microarray datasets with known tissue-specific gene expression changes. These tests showed that ZEOGS could reliably identify the tissues affected, whereas only very few enriched terms to none were found in the random gene sets. Next we applied ZEOGS to microarray datasets of 24 and 72 h postfertilization zebrafish embryos treated with beclomethasone, a potent glucocorticoid. This analysis resulted in the identification of several anatomical terms related to glucocorticoid-responsive tissues, some of which were stage-specific. Our studies highlight the ability of ZEOGS to extract spatial information from datasets derived from whole embryos, indicating that ZEOGS could be a useful tool to automatically analyze gene expression

  17. Landscape pattern and its restoration for coal mine subsidence area in southern part of Tangshan in China

    Institute of Scientific and Technical Information of China (English)

    CHEN Ying; ZHANG Tie-min; BIAN Lu-feng; BO Li-jie; CUI Jian-yu; HU Lin

    2009-01-01

    To investigate the ecosystem damage and environment pollution resulted from coal resources exploitation, based on remote sensing image, the landscape pattern was quantitatively analyzed with GIS and landscape pattern analysis software FRAGSTATS by utilizing multiform landscape pattern indexes, such as patch area,patch circumference, patch number, fractal dimension, fragmentation index, connectivity index and so on. Resuits indicate that the restored landscape type occupies the control status and accounts for the majority of the whole area, and needs to be further restored and adjusted because of its internal body with smaller patches,lower fractal dimension and better connectivity. The landscape type without restoration has destroyed the ecology and beauty of the whole landscape. In addition, some suggestive instructions for restoring various kinds of patches are put forward according to the quantitative analysis.

  18. Spatial assessment of landscape ecological connectivity in different urban gradient.

    Science.gov (United States)

    Park, Sohyun

    2015-07-01

    Urbanization has resulted in remnant natural patches within cities that often have no connectivity among themselves and to natural reserves outside the urban area. Protecting ecological connectivity in fragmented urban areas is becoming crucial in maintaining urban biodiversity and securing critical habitat levels and configurations under continual development pressures. Nevertheless, few studies have been undertaken for urban landscapes. This study aims to assess ecological connectivity for a group of species that represent the urban desert landscape in the Phoenix metropolitan area and to compare the connectivity values along the different urban gradient. A GIS-based landscape connectivity model which relies upon ecological connectivity index (ECI) was developed and applied to this region. A GIS-based concentric buffering technique was employed to delineate conceptual boundaries for urban, suburban, and rural zones. The research findings demonstrated that urban habitats and potential habitat patches would be significantly influenced by future urban development. Particularly, the largest loss of higher connectivity would likely to be anticipated in the "in-between areas" where urban, suburban, and rural zones overlap one another. The connectivity maps would be useful to provide spatial identification regarding connectivity patterns and vulnerability for urban and suburban activities in this area. This study provides planners and landscape architects with a spatial guidance to minimize ecological fragmentation, which ultimately leads to urban landscape sustainability. This study suggests that conventional planning practices which disregard the ecological processes in urban landscapes need to integrate landscape ecology into planning and design strategies.

  19. Synaptic connectivity in engineered neuronal networks.

    Science.gov (United States)

    Molnar, Peter; Kang, Jung-Fong; Bhargava, Neelima; Das, Mainak; Hickman, James J

    2014-01-01

    We have developed a method to organize cells in dissociated cultures using engineered chemical clues on a culture surface and determined their connectivity patterns. Although almost all elements of the synaptic transmission machinery can be studied separately in single cell models in dissociated cultures, the complex physiological interactions between these elements are usually lost. Thus, factors affecting synaptic transmission are generally studied in organotypic cultures, brain slices, or in vivo where the cellular architecture generally remains intact. However, by utilizing engineered neuronal networks complex phenomenon such as synaptic transmission or synaptic plasticity can be studied in a simple, functional, cell culture-based system. We have utilized self-assembled monolayers and photolithography to create the surface templates. Embryonic hippocampal cells, plated on the resultant patterns in serum-free medium, followed the surface clues and formed the engineered neuronal networks. Basic whole-cell patch-clamp electrophysiology was applied to characterize the synaptic connectivity in these engineered two-cell networks. The same technology has been used to pattern other cell types such as cardiomyocytes or skeletal muscle fibers.

  20. Connect the future

    Institute of Scientific and Technical Information of China (English)

    李柯翰

    2015-01-01

    <正>China has been developed so rapidly that it economic strength grows fast like a rocket.It leads China to become the World’s second-largest economy.Because the change of our life conditions,more and more people are wiling to go abroad,in order to feel the fresh air,civilized language,advanced science,and harmony atmosphere,all of these things like baptism which shocked people’s heart.The pursuit of better life quality requires more and more important elements such as beautiful landscape,clean lake,elegant buildings,rigorous law and kind people,since the beauty of landscape depends on it’s quality,the prosperity of a country rely on it’s power.I’ve been dreaming to become a messenger who can establish connect between different countries and various people.

  1. Nevos de tejido conectivo Connective tissue nevi

    Directory of Open Access Journals (Sweden)

    RE Achenbach

    Full Text Available Comunicamos dos casos de nevo del tejido conectivo, el primero con patrón histológico mixto y el segundo con predominio de alteraciones en las fibras elásticas. No se constataron síndromes ni patología sistémica asociada. Un caso presentó disposición linear y un nevo acrómico asociado.Two cases of connective tissue nevi are reported, one of them with a mixed histopatologic pattern and one with elastin fibers diminished. None of the patients had systemic involvement or associated syndromes. The mixed connective tissue nevi type showed a linear distribution and has associated an acromic nevi.

  2. ToolConnect: A Functional Connectivity Toolbox for In vitro Networks

    Science.gov (United States)

    Pastore, Vito Paolo; Poli, Daniele; Godjoski, Aleksandar; Martinoia, Sergio; Massobrio, Paolo

    2016-01-01

    Nowadays, the use of in vitro reduced models of neuronal networks to investigate the interplay between structural-functional connectivity and the emerging collective dynamics is a widely accepted approach. In this respect, a relevant advance for this kind of studies has been given by the recent introduction of high-density large-scale Micro-Electrode Arrays (MEAs) which have favored the mapping of functional connections and the recordings of the neuronal electrical activity. Although, several toolboxes have been implemented to characterize network dynamics and derive functional links, no specifically dedicated software for the management of huge amount of data and direct estimation of functional connectivity maps has been developed. toolconnect offers the implementation of up to date algorithms and a user-friendly Graphical User Interface (GUI) to analyze recorded data from large scale networks. It has been specifically conceived as a computationally efficient open-source software tailored to infer functional connectivity by analyzing the spike trains acquired from in vitro networks coupled to MEAs. In the current version, toolconnect implements correlation- (cross-correlation, partial-correlation) and information theory (joint entropy, transfer entropy) based core algorithms, as well as useful and practical add-ons to visualize functional connectivity graphs and extract some topological features. In this work, we present the software, its main features and capabilities together with some demonstrative applications on hippocampal recordings. PMID:27065841

  3. ToolConnect: A Functional Connectivity Toolbox for In vitro Networks.

    Science.gov (United States)

    Pastore, Vito Paolo; Poli, Daniele; Godjoski, Aleksandar; Martinoia, Sergio; Massobrio, Paolo

    2016-01-01

    Nowadays, the use of in vitro reduced models of neuronal networks to investigate the interplay between structural-functional connectivity and the emerging collective dynamics is a widely accepted approach. In this respect, a relevant advance for this kind of studies has been given by the recent introduction of high-density large-scale Micro-Electrode Arrays (MEAs) which have favored the mapping of functional connections and the recordings of the neuronal electrical activity. Although, several toolboxes have been implemented to characterize network dynamics and derive functional links, no specifically dedicated software for the management of huge amount of data and direct estimation of functional connectivity maps has been developed. toolconnect offers the implementation of up to date algorithms and a user-friendly Graphical User Interface (GUI) to analyze recorded data from large scale networks. It has been specifically conceived as a computationally efficient open-source software tailored to infer functional connectivity by analyzing the spike trains acquired from in vitro networks coupled to MEAs. In the current version, toolconnect implements correlation- (cross-correlation, partial-correlation) and information theory (joint entropy, transfer entropy) based core algorithms, as well as useful and practical add-ons to visualize functional connectivity graphs and extract some topological features. In this work, we present the software, its main features and capabilities together with some demonstrative applications on hippocampal recordings.

  4. ToolConnect: a functional connectivity toolbox for in vitro networks

    Directory of Open Access Journals (Sweden)

    Vito Paolo Pastore

    2016-03-01

    Full Text Available Nowadays, the use of in vitro reduced models of neuronal networks to investigate the interplay between structural-functional connectivity and the emerging collective dynamics is a widely accepted approach. In this respect, a relevant advance for this kind of studies has been given by the recent introduction of high-density large-scale Micro-Electrode Arrays (MEAs which have favored the mapping of functional connections and the recordings of the neuronal electrical activity. Although several toolboxes have been implemented to characterize network dynamics and derive functional links, no specifically dedicated software for the management of huge amount of data and direct estimation of functional connectivity maps has been developed. TOOLCONNECT offers the implementation of up to date algorithms and a user-friendly Graphical User Interface (GUI to analyze recorded data from large scale networks. It has been specifically conceived as a computationally efficient open-source software tailored to infer functional connectivity by analyzing the spike trains acquired from in vitro networks coupled to MEAs. In the current version, TOOLCONNECT implements correlation- (cross-correlation, partial-correlation and information theory (joint entropy, transfer entropy based core algorithms, as well as useful and practical add-ons to visualize functional connectivity graphs and extract some topological features. In this work, we present the software, its main features and capabilities together with some demonstrative applications on hippocampal recordings.

  5. Texas and Louisiana coastal vulnerability and shelf connectivity.

    Science.gov (United States)

    Thyng, Kristen M; Hetland, Robert D

    2017-03-15

    A numerical study of connectivity between the continental shelf and coast in the northwestern Gulf of Mexico using a circulation model and surface-limited numerical drifters shows that despite seasonal changes in winds, the overall connectivity of the shelf with the coastline is similar in the winter and summer, though it extends more offshore in Texas in summer. However, there is a spatial pattern to the connectivity: more of the inner shelf is connected with the coast in Texas as compared with Louisiana. Subsets of the coast do have seasonal variability: the coast near both Galveston and Port Aransas has more connectivity from upcoast in the winter and from offshore and downcoast in the summer. In both seasons, we find drifters reach the Port Aransas coast most frequently, with a stronger trend in the summer. These results are important for assessing likely pathways for spilled oil and other potentially hazardous material.

  6. Objects in Films: analyzing signs

    Directory of Open Access Journals (Sweden)

    GAMBARATO, Renira Rampazzo

    2009-12-01

    Full Text Available The focus of this essay is the analysis of daily objects as signs in films. Objects from everyday life acquire several functions in films: they can be solely used as scene objects or to support a particular film style. Other objects are specially chosen to translate a character’s interior state of mind or the filmmaker’s aesthetical or ethical commitment to narrative concepts. In order to understand such functions and commitments, we developed a methodology for film analysis which focuses on the objects. Object interpretation, as the starting point of film analysis, is not a new approach. For instance, French film critic André Bazin proposed that use of object interpretation in the 1950s. Similarly, German film theorist Siegfried Kracauer stated it in the 1960s. However, there is currently no existing analytical model to use when engaging in object interpretation in film. This methodology searches for the most representative objects in films which involves both quantitative and qualitative analysis; we consider the number of times each object appears in a film (quantitative analysis as well as the context of their appearance, i.e. the type of shot used and how that creates either a larger or smaller relevance and/or expressiveness (qualitative analysis. In addition to the criteria of relevance and expressiveness, we also analyze the functionality of an object by exploring details and specifying the role various objects play in films. This research was developed at Concordia University, Montreal, Canada and was supported by the Foreign Affairs and International Trade, Canada (DFAIT.

  7. Disruption of an Evolutionarily Novel Synaptic Expression Pattern in Autism

    Science.gov (United States)

    Jiang, Xi; Hu, Haiyang; Guijarro, Patricia; Mitchell, Amanda; Ely, John J.; Sherwood, Chet C.; Hof, Patrick R.; Qiu, Zilong; Pääbo, Svante; Akbarian, Schahram; Khaitovich, Philipp

    2016-01-01

    Cognitive defects in autism spectrum disorder (ASD) include socialization and communication: key behavioral capacities that separate humans from other species. Here, we analyze gene expression in the prefrontal cortex of 63 autism patients and control individuals, as well as 62 chimpanzees and macaques, from natal to adult age. We show that among all aberrant expression changes seen in ASD brains, a single aberrant expression pattern overrepresented in genes involved synaptic-related pathways is enriched in nucleotide variants linked to autism. Furthermore, only this pattern contains an excess of developmental expression features unique to humans, thus resulting in the disruption of human-specific developmental programs in autism. Several members of the early growth response (EGR) transcription factor family can be implicated in regulation of this aberrant developmental change. Our study draws a connection between the genetic risk architecture of autism and molecular features of cortical development unique to humans. PMID:27685936

  8. Imaging of Pulmonary Manifestations of Connective Tissue Diseases.

    Science.gov (United States)

    Ahuja, Jitesh; Arora, Deepika; Kanne, Jeffrey P; Henry, Travis S; Godwin, J David

    2016-11-01

    Connective tissue diseases (CTDs) are a heterogeneous group of conditions characterized by circulating autoantibodies and autoimmune-mediated organ damage. Common CTDs with lung manifestations are rheumatoid arthritis, scleroderma or systemic sclerosis, Sjögren syndrome, polymyositis/dermatomyositis, systemic lupus erythematosis, mixed connective tissue disease, and undifferentiated connective tissue disease. The most common histopathologic patterns of CTD-related interstitial lung disease are nonspecific interstitial pneumonia, usual interstitial pneumonia, organizing pneumonia, and lymphoid interstitial pneumonia. Drug treatment of CTDs can cause complications, including opportunistic infection.

  9. Communication of brain network core connections altered in behavioral variant frontotemporal dementia but possibly preserved in early-onset Alzheimer's disease

    Science.gov (United States)

    Daianu, Madelaine; Jahanshad, Neda; Mendez, Mario F.; Bartzokis, George; Jimenez, Elvira E.; Thompson, Paul M.

    2015-03-01

    Diffusion imaging and brain connectivity analyses can assess white matter deterioration in the brain, revealing the underlying patterns of how brain structure declines. Fiber tractography methods can infer neural pathways and connectivity patterns, yielding sensitive mathematical metrics of network integrity. Here, we analyzed 1.5-Tesla wholebrain diffusion-weighted images from 64 participants - 15 patients with behavioral variant frontotemporal dementia (bvFTD), 19 with early-onset Alzheimer's disease (EOAD), and 30 healthy elderly controls. Using whole-brain tractography, we reconstructed structural brain connectivity networks to map connections between cortical regions. We evaluated the brain's networks focusing on the most highly central and connected regions, also known as hubs, in each diagnostic group - specifically the "high-cost" structural backbone used in global and regional communication. The high-cost backbone of the brain, predicted by fiber density and minimally short pathways between brain regions, accounted for 81-92% of the overall brain communication metric in all diagnostic groups. Furthermore, we found that the set of pathways interconnecting high-cost and high-capacity regions of the brain's communication network are globally and regionally altered in bvFTD, compared to healthy participants; however, the overall organization of the high-cost and high-capacity networks were relatively preserved in EOAD participants, relative to controls. Disruption of the major central hubs that transfer information between brain regions may impair neural communication and functional integrity in characteristic ways typical of each subtype of dementia.

  10. Chladni Pattern

    OpenAIRE

    Xiao, Wence

    2010-01-01

    The report aimed at mathematically describing the Chladni Pattern for a plate based on the equation of motion in two dimensions. It began with deriving the equation of motion of a single point from Newton’s laws, and later derived the equation of motion for the vibration in two dimension, and gave the normal modes through the method of separation of variables. The next was deriving the nodal pattern when the initial conditions and bound- ary conditions were given. At t...

  11. Acoustic Pattern Recognition on Android Devices

    DEFF Research Database (Denmark)

    Møller, Maiken Bjerg; Gaarsdal, Jesper; Steen, Kim Arild

    2013-01-01

    an Android application developed for acoustic pattern recognition of bird species. The acoustic data is recorded using a built-in microphone, and pattern recognition is performed on the device, requiring no network connection. The algorithm is implemented in C++ as a native Android module and the Open...

  12. Information storage capacity of incompletely connected associative memories.

    Science.gov (United States)

    Bosch, Holger; Kurfess, Franz J.

    1998-07-01

    In this paper, the memory capacity of incompletely connected associative memories is investigated. First, the capacity is derived for memories with fixed parameters. Optimization of the parameters yields a maximum capacity between 0.53 and 0.69 for hetero-association and half of it for autoassociation improving previously reported results. The maximum capacity grows with increasing connectivity of the memory and requires sparse input and output patterns. Further, parameters can be chosen in such a way that the information content per pattern asymptotically approaches 1 with growing size of the memory.

  13. Potential Synaptic Connectivity of Different Neurons onto Pyramidal Cells in a 3D Reconstruction of the Rat Hippocampus

    Directory of Open Access Journals (Sweden)

    Deepak eRopireddy

    2011-07-01

    Full Text Available Most existing connectomic data and ongoing efforts focus either on individual synapses (e.g. with electron microscopy or on regional connectivity (tract tracing. An individual pyramidal cell extends thousands of synapses over macroscopic distances (~cm. The contrasting requirements of high resolution and large field of view make it too challenging to acquire the entire synaptic connectivity for even a single typical cortical neuron. Light microscopy can image whole neuronal arbors and resolve dendritic branches. Analyzing connectivity in terms of close spatial appositions between axons and dendrites could thus bridge the opposite scales, from synaptic level to whole systems. In the mammalian cortex, structural plasticity of spines and boutons makes these ‘potential synapses’ functionally relevant to learning capability and memory capacity. To date, however, potential synapses have only been mapped in the surrounding of a neuron and relative to its local orientation rather than in a system-level anatomical reference. Here we overcome this limitation by estimating the potential connectivity of different neurons embedded into a detailed 3D reconstruction of the rat hippocampus. Axonal and dendritic trees were oriented with respect to hippocampal cytoarchitecture according to longitudinal and transversal curvatures. We report the potential connectivity onto pyramidal cell dendrites from the axons of a dentate granule cell, three CA3 pyramidal cells, one CA2 pyramidal cell, and 13 CA3b interneurons. The numbers, densities, and distributions of potential synapses were analyzed in each sub-region (e.g. CA3 vs. CA1, layer (e.g. oriens vs. radiatum, and septo-temporal location (e.g. dorsal vs. ventral. The overall ratio between the numbers of actual and potential synapses was ~0.20 for the granule and CA3 pyramidal cells. All potential connectivity patterns are strikingly dependent on the anatomical location of both pre-synaptic and post

  14. Connecting the Dots

    DEFF Research Database (Denmark)

    Hannesson, Hakon Jarl; Reimann-Andersen, Thorbjørn; Burelli, Paolo;

    2015-01-01

    In this paper we analyze narrative in interactive media with a special focus on emergent narrative. We detail the criteria for creation of an online questionnaire for the evaluation of emergent narrative as a subjective experience and present the result of a large scale survey in which it was app...

  15. Altered Functional Connectivity in Essential Tremor

    Science.gov (United States)

    Benito-León, Julián; Louis, Elan D.; Romero, Juan Pablo; Hernández-Tamames, Juan Antonio; Manzanedo, Eva; Álvarez-Linera, Juan; Bermejo-Pareja, Félix; Posada, Ignacio; Rocon, Eduardo

    2015-01-01

    Abstract Essential tremor (ET) has been associated with a spectrum of clinical features, with both motor and nonmotor elements, including cognitive deficits. We employed resting-state functional magnetic resonance imaging (fMRI) to assess whether brain networks that might be involved in the pathogenesis of nonmotor manifestations associated with ET are altered, and the relationship between abnormal connectivity and ET severity and neuropsychological function. Resting-state fMRI data in 23 ET patients (12 women and 11 men) and 22 healthy controls (HC) (12 women and 10 men) were analyzed using independent component analysis, in combination with a “dual-regression” technique, to identify the group differences of resting-state networks (RSNs) (default mode network [DMN] and executive, frontoparietal, sensorimotor, cerebellar, auditory/language, and visual networks). All participants underwent a neuropsychological and neuroimaging session, where resting-state data were collected. Relative to HC, ET patients showed increased connectivity in RSNs involved in cognitive processes (DMN and frontoparietal networks) and decreased connectivity in the cerebellum and visual networks. Changes in network integrity were associated not only with ET severity (DMN) and ET duration (DMN and left frontoparietal network), but also with cognitive ability. Moreover, in at least 3 networks (DMN and frontoparietal networks), increased connectivity was associated with worse performance on different cognitive domains (attention, executive function, visuospatial ability, verbal memory, visual memory, and language) and depressive symptoms. Further, in the visual network, decreased connectivity was associated with worse performance on visuospatial ability. ET was associated with abnormal brain connectivity in major RSNs that might be involved in both motor and nonmotor symptoms. Our findings underscore the importance of examining RSNs in this population as a biomarker of disease. PMID:26656325

  16. Functional connectivity of emotional processing in depression.

    LENUS (Irish Health Repository)

    Carballedo, Angela

    2012-02-01

    OBJECTIVES: The aim of the study is to map a neural network of emotion processing and to identify differences in major depression compared to healthy controls. It is hypothesized that intentional perception of emotional faces activates connections between amygdala (Demir et al.), orbitofrontal cortex (OFC), anterior cingulate cortex (ACC) and prefrontal cortex (PFC) and that frontal-amygdala connections are altered in major depressive disorder (MDD). METHODS: Fifteen medication-free patients with MDD and fifteen healthy controls were enrolled. All subjects were assessed using the same face-matching functional Magnetic Resonance Imaging (fMRI) task, known to involve those areas. Brain activations were obtained using Statistical Parametric Mapping version 5 (SPM5) for data analysis and MARSBAR for extracting of fMRI time series. Then data was analyzed using structural equation modeling (SEM). RESULTS: A valid model was established for the left and the right hemispheres showing a circuit involving ACC, OFC, PFC and AMY. The left hemisphere shows significant lower connectivity strengths in patients than controls, for the pathway that goes from AMY to the OF11, and a trend of higher connectivity in patients for the path that goes from the PF9 to the OF11. In the right hemisphere, patients show lower connectivity coefficients in the paths from the AMY to OF11, from the AMY to ACC, and from the ACC to PF9. By the contrary, controls show lower connectivity strengths for the path that goes from ACC to AMY. CONCLUSIONS: Functional disconnection between limbic and frontal brain regions could be demonstrated using structural equation modeling. The interpretation of these findings could be that there is an emotional processing bias with disconnection bilaterally between amygdala to orbitofrontal cortices and in addition a right disconnection between amygdala and ACC as well as between ACC and prefrontal cortex possibly in line with a more prominent role for the right hemisphere

  17. Hypothalamus-Olfactory System Crosstalk: Orexin as a Connecting Track in Mice.

    Directory of Open Access Journals (Sweden)

    Jean eGascuel

    2012-11-01

    Full Text Available It is well known that olfaction influences food intake, and almost vice versa, the nutritional status of individuals modulates olfactory sensitivity. However, the neuronal correlate of this relationship and the connections between the olfactory bulb and the hypothalamus is still poorly understood. The goal of this report is to analyze the type of connections between the olfactory bulb and hypothalamus focusing on the expression pattern of orexin A, a hypothalamic neuropeptide that is thought to play a role in sleep/wakefulness states. Interestingly, orexin A has also been described as a stimulator of food intake. Such an effect may be due in part to the stimulation of the olfactory bulbar pathway. In rats, orexin positive cells are strictly concentrated in the lateral hypothalamus while their projections invade nearly the entire brain including the olfactory system. Therefore, orexin appears to be a good candidate to play a pivotal role in connecting olfactory and hypothalamic pathways. So far, orexin expression has been described in rats but there is still a lack of information concerning its expression in the adult and developing mouse brain. In this context we revisited the orexin A expression pattern in adult and developing mice using immunohistological methods and confocal microscopy. Besides minor differences, we found that the expression pattern of orexin A in mice shares many features with that in rats. In the olfactory bulb, even though there are few orexin projections, they reach all the different layers of the olfactory bulb. In contrast with the presence of orexin projections in the Main Olfactory Bulb almost none have been found in the Accessory Olfactory Bulb. The developmental expression of orexin A supports the hypothesis that orexin expression only appears post-natally.

  18. Connecting, Framing, Challenging

    DEFF Research Database (Denmark)

    Markham, Annette

    in deep—often invisible—structures of communication patterns, software, politics, and habits. Every action by individuals—whether designers, teachers, programmers, marketers, researchers, policy makers, or consumers—reinforces, resists, and reconfigures existing ethical boundaries for what is acceptable...... and just. This talk proposes a framework of ethics in digital research that emphasizes a future-oriented “what if” approach. Placing more responsibility on one’s personal choices is not the most comfortable position, but as the world grows more technologically mediated and digitally saturated...

  19. Beyond Impervious: Urban Land-Cover Pattern Variation and Implications for Watershed Management

    Science.gov (United States)

    Beck, Scott M.; McHale, Melissa R.; Hess, George R.

    2016-07-01

    Impervious surfaces degrade urban water quality, but their over-coverage has not explained the persistent water quality variation observed among catchments with similar rates of imperviousness. Land-cover patterns likely explain much of this variation, although little is known about how they vary among watersheds. Our goal was to analyze a series of urban catchments within a range of impervious cover to evaluate how land-cover varies among them. We then highlight examples from the literature to explore the potential effects of land-cover pattern variability for urban watershed management. High-resolution (1 m2) land-cover data were used to quantify 23 land-cover pattern and stormwater infrastructure metrics within 32 catchments across the Triangle Region of North Carolina. These metrics were used to analyze variability in land-cover patterns among the study catchments. We used hierarchical clustering to organize the catchments into four groups, each with a distinct landscape pattern. Among these groups, the connectivity of combined land-cover patches accounted for 40 %, and the size and shape of lawns and buildings accounted for 20 %, of the overall variation in land-cover patterns among catchments. Storm water infrastructure metrics accounted for 8 % of the remaining variation. Our analysis demonstrates that land-cover patterns do vary among urban catchments, and that trees and grass (lawns) are divergent cover types in urban systems. The complex interactions among land-covers have several direct implications for the ongoing management of urban watersheds.

  20. Quantifying Riverscape Connectivity with Graph Theory

    Science.gov (United States)

    Carbonneau, P.; Milledge, D.; Sinha, R.; Tandon, S. K.

    2013-12-01

    connectivity structure of the Gangetic riverscape with fluvial remote sensing. Our study reach extends from the heavily dammed headwaters of the Bhagirathi, Mandakini and Alaknanda rivers which form the source of the Ganga to Allahabad ~900 km downstream on the main stem. We use Landsat-8 imagery as the baseline dataset. Channel width along the Ganga (i.e. Ganges) is often several kilometres. Therefore, the pan-sharpened 15m pixels of Landsat-8 are in fact capable of resolving inner channel features for over 80% of the channel length thus allowing a riverscape approach to be adopted. We examine the following connectivity metrics: size distribution of connected components, betweeness centrality and the integrated index of connectivity. A geographic perspective is added by mapping local (25 km-scale) values for these metrics in order to examine spatial patterns of connectivity. This approach allows us to map impacts of dam construction and has the potential to inform policy decisions in the area as well as open-up new avenues of investigation.

  1. The Connectivity Analysis of Intermittent Connected Wireless Network

    Institute of Scientific and Technical Information of China (English)

    Li Yun; Zhou Yahui; Liu Qilie; Wang Xiaoying

    2009-01-01

    The connectivity is a basic and important characteristic to the network, it expresses the situation of link connectivity directly, and provides important reference for the entire network plan. Using statistics and probability Theory, this article emphasizes the probability between any two nodes in the network which nodes are equally distributed and the connectivity of whole network. At last, this article has made verification through simulation and has made out a conclusion, the simulation result agrees with theoretical analysis.

  2. [Analysis of quantitative traits connected with seed weight and flowering terms in birdsfoot trefoil (Lotus corniculatus L.) plants].

    Science.gov (United States)

    Nikolaĭchuk, V I

    2000-01-01

    The nature of inheritance of characters connected with the seed size (seed mass) and quality of the shoots (germination energy, seed viability, general shoot length, shoot mass, dry weight of shoots) in Lotus corniculatus L. was analyzed. The investigations were carried out on plants of three varieties: the wild form from the Krasnodar Region and local forms MF1 and MF3. The correlation analysis was carried out. The pattern of inheritance in the terms of plant flowering and length of shoots were studied.

  3. YANA – a software tool for analyzing flux modes, gene-expression and enzyme activities

    Directory of Open Access Journals (Sweden)

    Engels Bernd

    2005-06-01

    Full Text Available Abstract Background A number of algorithms for steady state analysis of metabolic networks have been developed over the years. Of these, Elementary Mode Analysis (EMA has proven especially useful. Despite its low user-friendliness, METATOOL as a reliable high-performance implementation of the algorithm has been the instrument of choice up to now. As reported here, the analysis of metabolic networks has been improved by an editor and analyzer of metabolic flux modes. Analysis routines for expression levels and the most central, well connected metabolites and their metabolic connections are of particular interest. Results YANA features a platform-independent, dedicated toolbox for metabolic networks with a graphical user interface to calculate (integrating METATOOL, edit (including support for the SBML format, visualize, centralize, and compare elementary flux modes. Further, YANA calculates expected flux distributions for a given Elementary Mode (EM activity pattern and vice versa. Moreover, a dissection algorithm, a centralization algorithm, and an average diameter routine can be used to simplify and analyze complex networks. Proteomics or gene expression data give a rough indication of some individual enzyme activities, whereas the complete flux distribution in the network is often not known. As such data are noisy, YANA features a fast evolutionary algorithm (EA for the prediction of EM activities with minimum error, including alerts for inconsistent experimental data. We offer the possibility to include further known constraints (e.g. growth constraints in the EA calculation process. The redox metabolism around glutathione reductase serves as an illustration example. All software and documentation are available for download at http://yana.bioapps.biozentrum.uni-wuerzburg.de. Conclusion A graphical toolbox and an editor for METATOOL as well as a series of additional routines for metabolic network analyses constitute a new user

  4. Focal pontine lesions provide evidence that intrinsic functional connectivity reflects polysynaptic anatomical pathways.

    Science.gov (United States)

    Lu, Jie; Liu, Hesheng; Zhang, Miao; Wang, Danhong; Cao, Yanxiang; Ma, Qingfeng; Rong, Dongdong; Wang, Xiaoyi; Buckner, Randy L; Li, Kuncheng

    2011-10-19

    Intrinsic functional connectivity detected by functional MRI (fMRI) provides a useful but indirect approach to study the organization of human brain systems. An unresolved question is whether functional connectivity measured by resting-state fMRI reflects anatomical connections. In this study, we used the well-characterized anatomy of cerebrocerebellar circuits to directly test whether intrinsic functional connectivity is associated with an anatomic pathway. Eleven first-episode stroke patients were scanned five times during a period of 6 months, and 11 healthy control subjects were scanned three times within 1 month. In patients with right pontine strokes, the functional connectivity between the right motor cortex and the left cerebellum was selectively reduced. This connectivity pattern was reversed in patients with left pontine strokes. Although factors beyond anatomical connectivity contribute to fMRI measures of functional correlation, these results provide direct evidence that functional connectivity depends on intact connections within a specific polysynaptic pathway.

  5. Watch out for superman: first visualize, then analyze.

    Science.gov (United States)

    Kozak, Marcin

    2012-01-01

    A visit from Superman shows why data visualization should come before data analysis. The Web extra is a dataset that comprises 100 observations of the quantitative variables y and x plus the qualitative variable group. When analyzed correctly, this dataset exhibits an interesting pattern.

  6. A Study Analyzing the Career Path of Librarians

    Science.gov (United States)

    Noh, Younghee

    2010-01-01

    This study aims to identify the career movement patterns of librarians, analyze factors influencing their career movements, and compare differences in such factors between librarians and chief librarians. Findings showed that the jobs with the highest retention rate were those in public libraries, that library automation system developers showed…

  7. Pattern Formation

    Science.gov (United States)

    Hoyle, Rebecca

    2006-03-01

    From the stripes of a zebra and the spots on a leopard's back to the ripples on a sandy beach or desert dune, regular patterns arise everywhere in nature. The appearance and evolution of these phenomena has been a focus of recent research activity across several disciplines. This book provides an introduction to the range of mathematical theory and methods used to analyse and explain these often intricate and beautiful patterns. Bringing together several different approaches, from group theoretic methods to envelope equations and theory of patterns in large-aspect ratio-systems, the book also provides insight behind the selection of one pattern over another. Suitable as an upper-undergraduate textbook for mathematics students or as a fascinating, engaging, and fully illustrated resource for readers in physics and biology, Rebecca Hoyle's book, using a non-partisan approach, unifies a range of techniques used by active researchers in this growing field. Accessible description of the mathematical theory behind fascinating pattern formation in areas such as biology, physics and materials science Collects recent research for the first time in an upper level textbook Features a number of exercises - with solutions online - and worked examples

  8. Cortico-cerebellar functional connectivity and sequencing of movements in schizophrenia

    Directory of Open Access Journals (Sweden)

    Kasparek Tomas

    2012-03-01

    Full Text Available Abstract Background Abnormal execution of several movements in a sequence is a frequent finding in schizophrenia. Successful performance of such motor acts requires correct integration of cortico-subcortical processes, particularly those related to cerebellar functions. Abnormal connectivity between cortical and cerebellar regions with resulting cognitive dysmetria has been proposed as the core dysfunction behind many signs and symptoms of schizophrenia. The aim of the present study was to assess if these proposed abnormalities in connectivity are a unifying feature of schizophrenia, or, rather, reflect a specific symptom domain of a heterogeneous disease. We predicted that abnormal functional connectivity between the motor cortex and cerebellum would be linked with abnormal performance of movement sequencing. Methods We examined 24 schizophrenia patients (SCH and 24 age-, sex-, and handedness-matched healthy controls (HC using fMRI during a modified finger-tapping task. The ability to perform movement sequencing was tested using the Neurological Evaluation Scale (NES. The subjects were categorized into two groups, with (SQ+ and without (SQ- movement sequencing abnormalities, according to the NES-SQ score. The effects of diagnosis and movement sequencing abnormalities on the functional connectivity parameters between the motor cortex and cerebellum (MC-CRBL and the supplementary motor cortex and cerebellum (SMA-CRBL activated during the motor task were analyzed. Results We found no effect of diagnosis on the functional connectivity measures. There was, however, a significant effect on the SQ group: SQ + patients showed a lower level of MC-CRBL connectivity than SQ- patients and healthy controls. Moreover, the level of MC-CRBL and SMA-CRBL negatively correlated with the magnitude of NES-SQ abnormalities, but with no other NES domain. Conclusions Abnormal cortico-cerebellar functional connectivity during the execution of a motor task is linked

  9. Altered Resting-State EEG Source Functional Connectivity In Schizophrenia: The Effect Of Illness Duration

    Directory of Open Access Journals (Sweden)

    Giorgio eDi Lorenzo

    2015-05-01

    Full Text Available Despite the increasing body of evidence supporting the hypothesis of schizophrenia as a disconnection syndrome, studies of resting-state EEG Source Functional Connectivity (EEG-SFC in people affected by schizophrenia are sparse. The aim of the present study was to investigate resting-state EEG-SFC in 77 stable, medicated patients with schizophrenia (SCZ compared to 78 healthy volunteers (HV. In order to study the effect of illness duration, SCZ were divided in those with a short duration of disease (SDD; n = 25 and those with a long duration of disease (LDD; n = 52. Resting-state EEG recordings in eyes closed condition were analyzed and lagged phase synchronization (LPS indices were calculated for each ROI pair in the source-space EEG data. In delta and theta bands, SCZ had greater EEG-SFC than HV; a higher theta band connectivity in frontal regions was observed in LDD compared with SDD. In the alpha band, SCZ showed lower frontal EEG-SFC compared with HV whereas no differences were found between LDD and SDD. In the beta1 band, SCZ had greater EEG-SFC compared with HVs and in the beta2 band, LDD presented lower frontal and parieto-temporal EEG-SFC compared with HV. In the gamma band, SDD had greater connectivity values compared with LDD and HV. This study suggests that resting state brain network connectivity is abnormally organized in schizophrenia, with different patterns for the different EEG frequency components and that EEG can be a powerful tool to further elucidate the complexity of such disordered connectivity.

  10. Fish utilisation of wetland nurseries with complex hydrological connectivity.

    Science.gov (United States)

    Davis, Ben; Johnston, Ross; Baker, Ronald; Sheaves, Marcus

    2012-01-01

    The physical and faunal characteristics of coastal wetlands are driven by dynamics of hydrological connectivity to adjacent habitats. Wetlands on estuary floodplains are particularly dynamic, driven by a complex interplay of tidal marine connections and seasonal freshwater flooding, often with unknown consequences for fish using these habitats. To understand the patterns and subsequent processes driving fish assemblage structure in such wetlands, we examined the nature and diversity of temporal utilisation patterns at a species or genus level over three annual cycles in a tropical Australian estuarine wetland system. Four general patterns of utilisation were apparent based on CPUE and size-structure dynamics: (i) classic nursery utlisation (use by recently settled recruits for their first year) (ii) interrupted peristence (iii) delayed recruitment (iv) facultative wetland residence. Despite the small self-recruiting 'facultative wetland resident' group, wetland occupancy seems largely driven by connectivity to the subtidal estuary channel. Variable connection regimes (i.e. frequency and timing of connections) within and between different wetland units (e.g. individual pools, lagoons, swamps) will therefore interact with the diversity of species recruitment schedules to generate variable wetland assemblages in time and space. In addition, the assemblage structure is heavily modified by freshwater flow, through simultaneously curtailing persistence of the 'interrupted persistence' group, establishing connectivity for freshwater spawned members of both the 'facultative wetland resident' and 'delayed recruitment group', and apparently mediating use of intermediate nursery habitats for marine-spawned members of the 'delayed recruitment' group. The diversity of utilisation pattern and the complexity of associated drivers means assemblage compositions, and therefore ecosystem functioning, is likely to vary among years depending on variations in hydrological connectivity

  11. The Chitin Connection

    Science.gov (United States)

    Goldman, David L.; Vicencio, Alfin G.

    2012-01-01

    ABSTRACT Chitin, a polymer of N-acetylglucosamine, is an essential component of the fungal cell wall. Chitosan, a deacetylated form of chitin, is also important in maintaining cell wall integrity and is essential for Cryptococcus neoformans virulence. In their article, Gilbert et al. [N. M. Gilbert, L. G. Baker, C. A. Specht, and J. K. Lodge, mBio 3(1):e00007-12, 2012] demonstrate that the enzyme responsible for chitosan synthesis, chitin deacetylase (CDA), is differentially attached to the cell membrane and wall. Bioactivity is localized to the cell membrane, where it is covalently linked via a glycosylphosphatidylinositol (GPI) anchor. Findings from this study significantly enhance our understanding of cryptococcal cell wall biology. Besides the role of chitin in supporting structural stability, chitin and host enzymes with chitinase activity have an important role in host defense and modifying the inflammatory response. Thus, chitin appears to provide a link between the fungus and host that involves both innate and adaptive immune responses. Recently, there has been increased attention to the role of chitinases in the pathogenesis of allergic inflammation, especially asthma. We review these findings and explore the possible connection between fungal infections, the induction of chitinases, and asthma. PMID:22448043

  12. Formal connections in deformation quantization

    DEFF Research Database (Denmark)

    Masulli, Paolo

    attention on symplectic manifolds equipped with a family of star products, indexed by a parameter space. In this situation we can define a connection in the trivial bundle over the parameter space with fibres the formal smooth functions on the manifold, which relates the star products in the family...... and is called a formal connection. We study the question of classifying such formal connections. To each star product we can associate a certain cohomology class called the characteristic class. It turns out that a formal connection exists if and only if all the star products in the family have the same...... characteristic class, and that formal connections form an affine space over the derivations of the star products. Moreover, if the parameter space for the family of star products is contractible, we obtain that any two flat formal connections are gauge equivalent via a self-equivalence of the family of star...

  13. Hitchin's connection in metaplectic quantization

    DEFF Research Database (Denmark)

    Andersen, Jørgen Ellegaard; Gammelgaard, Niels Leth; Lauridsen, Magnus Roed

    2012-01-01

    We give a differential geometric construction of a connection, which we call the Hitchin connection, in the bundle of quantum Hilbert spaces arising from metaplectically corrected geometric quantization of a prequantizable, symplectic manifold, endowed with a rigid family of Kähler structures, all...... manifold in question. Furthermore, when we are in a setting similar to the moduli space, we give an explicit formula and show that this connection agrees with previous constructions....

  14. Characterizing Information Flux Within the Distributed Pediatric Expressive Language Network: A Core Region Mapped Through fMRI-Constrained MEG Effective Connectivity Analyses.

    Science.gov (United States)

    Kadis, Darren S; Dimitrijevic, Andrew; Toro-Serey, Claudio A; Smith, Mary Lou; Holland, Scott K

    2016-02-01

    Using noninvasive neuroimaging, researchers have shown that young children have bilateral and diffuse language networks, which become increasingly left lateralized and focal with development. Connectivity within the distributed pediatric language network has been minimally studied, and conventional neuroimaging approaches do not distinguish task-related signal changes from those that are task essential. In this study, we propose a novel multimodal method to map core language sites from patterns of information flux. We retrospectively analyze neuroimaging data collected in two groups of children, ages 5-18 years, performing verb generation in functional magnetic resonance imaging (fMRI) (n = 343) and magnetoencephalography (MEG) (n = 21). The fMRI data were conventionally analyzed and the group activation map parcellated to define node locations. Neuronal activity at each node was estimated from MEG data using a linearly constrained minimum variance beamformer, and effective connectivity within canonical frequency bands was computed using the phase slope index metric. We observed significant (p ≤ 0.05) effective connections in all subjects. The number of suprathreshold connections was significantly and linearly correlated with participant's age (r = 0.50, n = 21, p ≤ 0.05), suggesting that core language sites emerge as part of the normal developmental trajectory. Across frequencies, we observed significant effective connectivity among proximal left frontal nodes. Within the low frequency bands, information flux was rostrally directed within a focal, left frontal region, approximating Broca's area. At higher frequencies, we observed increased connectivity involving bilateral perisylvian nodes. Frequency-specific differences in patterns of information flux were resolved through fast (i.e., MEG) neuroimaging.

  15. Interstate Connections - CEHC [ds619

    Data.gov (United States)

    California Department of Resources — The California Department of Transportation (Caltrans) and California Department of Fish and Game (CDFG) commissioned the California Essential Habitat Connectivity...

  16. Lateral-Medial Dissociation in Orbitofrontal Cortex-Hypothalamus Connectivity.

    Science.gov (United States)

    Hirose, Satoshi; Osada, Takahiro; Ogawa, Akitoshi; Tanaka, Masaki; Wada, Hiroyuki; Yoshizawa, Yasunori; Imai, Yoshio; Machida, Toru; Akahane, Masaaki; Shirouzu, Ichiro; Konishi, Seiki

    2016-01-01

    The orbitofrontal cortex (OFC) is involved in cognitive functions, and is also closely related to autonomic functions. The OFC is densely connected with the hypothalamus, a heterogeneous structure controlling autonomic functions that can be divided into two major parts: the lateral and the medial. Resting-state functional connectivity has allowed us to parcellate the cerebral cortex into putative functional areas based on the changes in the spatial pattern of connectivity in the cerebral cortex when a seed point is moved from one voxel to another. In the present high spatial-resolution fMRI study, we investigate the connectivity-based organization of the OFC with reference to the hypothalamus. The OFC was parcellated using resting-state functional connectivity in an individual subject approach, and then the functional connectivity was examined between the parcellated areas in the OFC and the lateral/medial hypothalamus. We found a functional double dissociation in the OFC: the lateral OFC (the lateral orbital gyrus) was more likely connected with the lateral hypothalamus, whereas the medial OFC (the medial orbital and rectal gyri) was more likely connected with the medial hypothalamus. These results demonstrate the fundamental heterogeneity of the OFC, and suggest a potential neural basis of the OFC-hypothalamic functional interaction.

  17. Social network models predict movement and connectivity in ecological landscapes

    Science.gov (United States)

    Fletcher, Robert J.; Acevedo, M.A.; Reichert, Brian E.; Pias, Kyle E.; Kitchens, Wiley M.

    2011-01-01

    Network analysis is on the rise across scientific disciplines because of its ability to reveal complex, and often emergent, patterns and dynamics. Nonetheless, a growing concern in network analysis is the use of limited data for constructing networks. This concern is strikingly relevant to ecology and conservation biology, where network analysis is used to infer connectivity across landscapes. In this context, movement among patches is the crucial parameter for interpreting connectivity but because of the difficulty of collecting reliable movement data, most network analysis proceeds with only indirect information on movement across landscapes rather than using observed movement to construct networks. Statistical models developed for social networks provide promising alternatives for landscape network construction because they can leverage limited movement information to predict linkages. Using two mark-recapture datasets on individual movement and connectivity across landscapes, we test whether commonly used network constructions for interpreting connectivity can predict actual linkages and network structure, and we contrast these approaches to social network models. We find that currently applied network constructions for assessing connectivity consistently, and substantially, overpredict actual connectivity, resulting in considerable overestimation of metapopulation lifetime. Furthermore, social network models provide accurate predictions of network structure, and can do so with remarkably limited data on movement. Social network models offer a flexible and powerful way for not only understanding the factors influencing connectivity but also for providing more reliable estimates of connectivity and metapopulation persistence in the face of limited data.

  18. Analyzing multiple spike trains with nonparametric Granger causality.

    Science.gov (United States)

    Nedungadi, Aatira G; Rangarajan, Govindan; Jain, Neeraj; Ding, Mingzhou

    2009-08-01

    Simultaneous recordings of spike trains from multiple single neurons are becoming commonplace. Understanding the interaction patterns among these spike trains remains a key research area. A question of interest is the evaluation of information flow between neurons through the analysis of whether one spike train exerts causal influence on another. For continuous-valued time series data, Granger causality has proven an effective method for this purpose. However, the basis for Granger causality estimation is autoregressive data modeling, which is not directly applicable to spike trains. Various filtering options distort the properties of spike trains as point processes. Here we propose a new nonparametric approach to estimate Granger causality directly from the Fourier transforms of spike train data. We validate the method on synthetic spike trains generated by model networks of neurons with known connectivity patterns and then apply it to neurons simultaneously recorded from the thalamus and the primary somatosensory cortex of a squirrel monkey undergoing tactile stimulation.

  19. Hydrological connectivity for riverine fish: measurement challenges and research opportunities

    Science.gov (United States)

    Fullerton, A.H.; Burnett, K.M.; Steel, E.A.; Flitcroft, R.L.; Pess, G.R.; Feist, B.E.; Torgersen, C.E.; Miller, D.J.; Sanderson, B.L.

    2010-01-01

    possible in the following arenas: (i) incorporating network structure and river discharge into analyses; (ii) increasing explicit consideration of temporal complexity and fish behaviour in the scope of analyses; and (iii) parsing degrees of human and natural influences on connectivity and defining acceptable alterations. Multiscale analyses are most likely to identify dominant patterns of connections and disconnections, and the appropriate scale at which to focus conservation activities.

  20. Carl Sagan's Cosmic Connection

    Science.gov (United States)

    Sagan, Carl; Agel, Jerome

    2000-08-01

    Foreword Freeman Dyson; Personal reflections Ann Druyan; Preface; Part I. Cosmic Perspective: 1. A transitional animal; 2. The Unicorn of Cetus; 3. A message from earth; 4. A message to earth; 5. Experiments in utopias; 6. Chauvinism; 7. Space exploration as a human enterprise I. The scientific interest; 8. Space exploration as a human enterprise II. The public interest; 9. Space exploration as a human enterprise III. The historical interest; Part II. The Solar System: 10. On teaching the first grade; 11. 'The ancient and legendary Gods of old'; 12. The Venus detective story; 13. Venus is hell; 14. Science and 'intelligence'; 15. The moons of Barsoom; 16. The mountains of Mars I. Observations from earth; 17. The mountains of Mars II. Observations from space; 18. The canals of Mars; 19. The lost pictures of Mars; 20. The Ice Age and the cauldron; 21. Beginnings and ends of the Earth; 22. Terraforming the plants; 23. The exploration and utlization of the solar system; Part III. Beyond the Solar System: 24. Some of my best friends are dolphins; 25. 'Hello, central casting? Send me twenty extraterrestrials'; 26. The cosmic connection; 27. Extraterrestrial life: an idea whose time has come; 28. Has the Earth been visited?; 29. A search strategy for detecting extraterrestrial intelligence; 30. If we succeed 31. Cables, drums, and seashells; 32. The night freight to the stars; 33. Astroengineering; 34. Twenty questions: a classification of cosmic civilisations; 35. Galactic cultural exchanges; 36. A passage to elsewhere; 37. Starfolk I. A Fable; 38. Starfolk II. A future; 39. Starfolk III. The cosmic Cheshire cats; Epilog David Morrison; Index.

  1. Signal processing and analyzing works of art

    Science.gov (United States)

    Johnson, Don H.; Johnson, C. Richard, Jr.; Hendriks, Ella

    2010-08-01

    In examining paintings, art historians use a wide variety of physico-chemical methods to determine, for example, the paints, the ground (canvas primer) and any underdrawing the artist used. However, the art world has been little touched by signal processing algorithms. Our work develops algorithms to examine x-ray images of paintings, not to analyze the artist's brushstrokes but to characterize the weave of the canvas that supports the painting. The physics of radiography indicates that linear processing of the x-rays is most appropriate. Our spectral analysis algorithms have an accuracy superior to human spot-measurements and have the advantage that, through "short-space" Fourier analysis, they can be readily applied to entire x-rays. We have found that variations in the manufacturing process create a unique pattern of horizontal and vertical thread density variations in the bolts of canvas produced. In addition, we measure the thread angles, providing a way to determine the presence of cusping and to infer the location of the tacks used to stretch the canvas on a frame during the priming process. We have developed weave matching software that employs a new correlation measure to find paintings that share canvas weave characteristics. Using a corpus of over 290 paintings attributed to Vincent van Gogh, we have found several weave match cliques that we believe will refine the art historical record and provide more insight into the artist's creative processes.

  2. Different types of connective tissue alterations associated with cervical artery dissections.

    Science.gov (United States)

    Hausser, Ingrid; Müller, Uta; Engelter, Stefan; Lyrer, Philippe; Pezzini, Alessandro; Padovani, Alessandro; Moormann, Birgit; Busse, Otto; Weber, Ralf; Brandt, Tobias; Grond-Ginsbach, Caspar

    2004-06-01

    This study describes the technical handling and the diagnostic evaluation of skin biopsies in order to standardize the assessment of the delicate morphologic abnormalities that are found in patients with spontaneous cervical artery dissections (sCAD). Skin biopsies from 126 patients with sCAD and from 29 healthy relatives were analyzed. The morphology of the connective tissue was normal in 54 patients with sCAD (43%) and aberrant in 72 patients with sCAD (57%). These latter patients were classified into three groups: in 43 patients, we repeatedly observed composite collagen fibrils and elastic fibers with fragmentation and minicalcifications. In 13 further patients, the dermis was significantly thinner than in healthy subjects. The collagen fibers contained fibrils with highly variable diameters. In a third group of 16 sCAD patients, the abnormalities were restricted to the elastic fibers (with fragmentation and minicalcifications) without significant alterations in the morphology of the collagen fibrils. The finding of different morphologic classes of aberrations among patients suggests that the connective tissue defects are genetically heterogeneous. The segregation of the connective tissue phenotype in three families suggested an autosomal dominant pattern of inheritance.

  3. General human activity patterns

    CERN Document Server

    Mollgaard, Anders; Mathiesen, Joachim

    2016-01-01

    We investigate the dynamics and interplay between human communication, movement, and social proximity by analyzing data collected from smartphones distributed among 638 individuals. The main question we consider is: to what extent do individuals act according to patterns shared across an entire population? Based on statistics of the entire population, we successfully predict 71\\% of the activity and 85\\% of the inactivity involved in communication, movement, and social proximity. We find that individual level statistics only result in marginally better predictions, indicating a high degree of shared activity patterns across the population. Finally, we predict short-term activity patterns using a generalized linear model, which suggests that a simple linear description might be sufficient to explain a wide range of actions, whether they be of social or of physical character.

  4. Multiple neural representations of elementary logical connectives.

    Science.gov (United States)

    Baggio, Giosuè; Cherubini, Paolo; Pischedda, Doris; Blumenthal, Anna; Haynes, John-Dylan; Reverberi, Carlo

    2016-07-15

    A defining trait of human cognition is the capacity to form compounds out of simple thoughts. This ability relies on the logical connectives AND, OR and IF. Simple propositions, e.g., 'There is a fork' and 'There is a knife', can be combined in alternative ways using logical connectives: e.g., 'There is a fork AND there is a knife', 'There is a fork OR there is a knife', 'IF there is a fork, there is a knife'. How does the brain represent compounds based on different logical connectives, and how are compounds evaluated in relation to new facts? In the present study, participants had to maintain and evaluate conjunctive (AND), disjunctive (OR) or conditional (IF) compounds while undergoing functional MRI. Our results suggest that, during maintenance, the left posterior inferior frontal gyrus (pIFG, BA44, or Broca's area) represents the surface form of compounds. During evaluation, the left pIFG switches to processing the full logical meaning of compounds, and two additional areas are recruited: the left anterior inferior frontal gyrus (aIFG, BA47) and the left intraparietal sulcus (IPS, BA40). The aIFG shows a pattern of activation similar to pIFG, and compatible with processing the full logical meaning of compounds, whereas activations in IPS differ with alternative interpretations of conditionals: logical vs conjunctive. These results uncover the functions of a basic cortical network underlying human compositional thought, and provide a shared neural foundation for the cognitive science of language and reasoning.

  5. Effects of Auxiliary-Source Connection in Multichip Power Module

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Wang, Xiongfei

    2017-01-01

    the power loop and the gate loop like how the Kelvin-source connection does, owing to their involvement in the loop of the power source current. Three effects of the auxiliary-source connections are then analyzed, which are 1) the common source stray inductance reduction, 2) the transient drain......Auxiliary-source bond wires and connections are widely used in power modules with paralleled MOSFETs or IGBTs. This paper investigates the operation mechanism of the auxiliary-source connections in multichip power modules. It reveals that the auxiliary-source connections cannot fully decouple......-source current imbalance mitigation, and 3) the influence on the steady-state current distribution. Lastly, simulations and experimental results validate the theoretical analysis....

  6. Interference Alignment for Partially Connected MIMO Cellular Networks

    CERN Document Server

    Ruan, Liangzhong

    2012-01-01

    In this paper, we propose an iterative interference alignment (IA) algorithm for MIMO cellular networks with partial connectivity, which is induced by heterogeneous path losses and spatial correlation. Such systems impose several key technical challenges in the IA algorithm design, namely the overlapping between the direct and interfering links due to the MIMO cellular topology as well as how to exploit the partial connectivity. We shall address these challenges and propose a three stage IA algorithm. As illustration, we analyze the achievable degree of freedom (DoF) of the proposed algorithm for a symmetric partially connected MIMO cellular network. We show that there is significant DoF gain compared with conventional IA algorithms due to partial connectivity. The derived DoF bound is also backward compatible with that achieved on fully connected K-pair MIMO interference channels.

  7. Financial Connections and Systemic Risk

    NARCIS (Netherlands)

    Allen, F.; Babus, A.; Carletti, E.

    2010-01-01

    We develop a model where institutions form connections through swaps of projects in order to diversify their individual risk. These connections lead to two different network structures. In a clustered network groups of financial institutions hold identical portfolios and default together. In an uncl

  8. [Muscles and connective tissue: histology].

    Science.gov (United States)

    Delage, J-P

    2012-10-01

    Here, we give some comments about the DVD movies "Muscle Attitudes" from Endovivo productions, the movies up lighting some loss in the attention given to studies on the connective tissue, and especially them into muscles. The main characteristics of the different components in the intra-muscular connective tissue (perimysium, endomysium, epimysium) are shown here with special references to their ordered architecture and special references to their spatial distributions. This connective tissue is abundant into the muscles and is in continuity with the muscles in vicinity, with their tendons and their sheath, sticking the whole on skin. This connective tissue has also very abundant connections on the muscles fibres. It is then assumed that the connective tissue sticks every organs or cells of the locomotion system. Considering the elastic properties of the collagen fibres which are the most abundant component of connective tissue, it is possible to up light a panel of connective tissue associated functions such as the transmission of muscle contractions or the regulation of protein and energetic muscles metabolism.

  9. Telephone Networks Connect Caregiving Families of Alzheimer's Victims.

    Science.gov (United States)

    Goodman, Catherine Chase; Pynoos, Jon

    1988-01-01

    Describes telephone network bringing family caregivers of Alzheimer's victims together over telephone in rotating pattern of twosomes. Explains how five caregiving spouses and five adult children were matched and connected over three months. Describes program's 25 telephone-accessed audiotapes that guided networks and provided information on…

  10. Clustering by Pattern Similarity

    Institute of Scientific and Technical Information of China (English)

    Hai-xun Wang; Jian Pei

    2008-01-01

    The task of clustering is to identify classes of similar objects among a set of objects. The definition of similarity varies from one clustering model to another. However, in most of these models the concept of similarity is often based on such metrics as Manhattan distance, Euclidean distance or other Lp distances. In other words, similar objects must have close values in at least a set of dimensions. In this paper, we explore a more general type of similarity. Under the pCluster model we proposed, two objects are similar if they exhibit a coherent pattern on a subset of dimensions. The new similarity concept models a wide range of applications. For instance, in DNA microarray analysis, the expression levels of two genes may rise and fall synchronously in response to a set of environmental stimuli. Although the magnitude of their expression levels may not be close, the patterns they exhibit can be very much alike. Discovery of such clusters of genes is essential in revealing significant connections in gene regulatory networks. E-commerce applications, such as collaborative filtering, can also benefit from the new model, because it is able to capture not only the closeness of values of certain leading indicators but also the closeness of (purchasing, browsing, etc.) patterns exhibited by the customers. In addition to the novel similarity model, this paper also introduces an effective and efficient algorithm to detect such clusters, and we perform tests on several real and synthetic data sets to show its performance.

  11. Analyzing Reactive Routing Protocols in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Dr. Kamaljit I. Lakhtaria

    2012-05-01

    Full Text Available Mobile Ad Hoc Network (MANET is an autonomous mobile nodes forming network in an infrastructure less environment and has dynamic topology. MANET reactive protocols always not have low control overhead. The control overhead for reactive protocols is more sensitive to the traffic load, in terms of the number of traffic rows, and mobility, in terms of link connectivity change rates, than other protocols. Therefore, reactive protocols may only be suitable for MANETs with small number of traffic loads and small link connectivity change rates. It is already proved that, it is more feasible to maintain full network topology in a MANET with low control overhead. In this Research Paper through simulations that were carried out by using Network Simulator-2 (NS-2 we had analyze Reactive/ On-demand protocols such as Ad Hoc On-Demand Distance Vector Routing (AODV, Temporally-Ordered Routing Algorithm (TORA, and Dynamic Source Routing (DSR,

  12. Brain oscillations and functional connectivity during overt language production

    Directory of Open Access Journals (Sweden)

    Arne eEwald

    2012-06-01

    Full Text Available In the present study we investigate the communication of different large scale brain sites during an overt language production task with state of the art methods for the estimation of EEG functional connectivity. Participants performed a semantic blocking task in which objects were named in semantically homogeneous blocks of trials consisting of members of a semantic category (e.g., all objects are tools or in heterogeneous blocks, consisting of unrelated objects. The classic pattern of slower naming times in the homogeneous relative to heterogeneous blocks is assumed to reflect the duration of lexical selection. For the collected data in the homogeneous and heterogeneous conditions the imaginary part of coherency (ImC was evaluated at different frequencies. The ImC is a measure for detecting the coupling of different brain sites acting on sensor level. Most importantly, a non-vanishing ImC cannot be explained by mixtures of independent sources and must therefore reflect true interactions. After performing a grand average over 24 subjects we analyzed the ImC at all pairs of 56 EEG channels across all frequencies. Contrasting the two experimental conditions we found differences in interaction between left temporal and frontal areas and frontal and occipital areas in the theta band at 7Hz, and also smaller differences in the delta and beta band. These areas are well-known to play a major role in lexical-semantic language processes. Our findings demonstrate the feasibility of investigating interactive brain activity during overt language production.

  13. Hierarchies of Predominantly Connected Communities

    CERN Document Server

    Hamann, Michael; Wagner, Dorothea

    2013-01-01

    We consider communities whose vertices are predominantly connected, i.e., the vertices in each community are stronger connected to other community members of the same community than to vertices outside the community. Flake et al. introduced a hierarchical clustering algorithm that finds such predominantly connected communities of different coarseness depending on an input parameter. We present a simple and efficient method for constructing a clustering hierarchy according to Flake et al. that supersedes the necessity of choosing feasible parameter values and guarantees the completeness of the resulting hierarchy, i.e., the hierarchy contains all clusterings that can be constructed by the original algorithm for any parameter value. However, predominantly connected communities are not organized in a single hierarchy. Thus, we develop a framework that, after precomputing at most $2(n-1)$ maximum flows, admits a linear time construction of a clustering $\\C(S)$ of predominantly connected communities that contains ...

  14. Altered default mode network functional connectivity in schizotypal personality disorder.

    Science.gov (United States)

    Zhang, Qing; Shen, Jing; Wu, Jianlin; Yu, Xiao; Lou, Wutao; Fan, Hongyu; Shi, Lin; Wang, Defeng

    2014-12-01

    The default mode network (DMN) has been identified to play a critical role in many mental disorders, but such abnormalities have not yet been determined in patients with schizotypal personality disorder (SPD). The purpose of this study was to analyze the alteration of the DMN functional connectivity in subjects with (SPD) and compared it to healthy control subjects. Eighteen DSM-IV diagnosed SPD subjects (all male, average age: 19.7±0.9) from a pool of 3000 first year college students, and eighteen age and gender matched healthy control subjects were recruited (all male, average age: 20.3±0.9). Independent component analysis (ICA) was used to analyze the DMN functional connectivity alteration. Compared to the healthy control group, SPD subjects had significantly decreased functional connectivity in the frontal areas, including the superior and medial frontal gyrus, and greater functional connectivity in the bilateral superior temporal gyrus and sub-lobar regions, including the bilateral putamen and caudate. Compared to subjects with SPD, the healthy control group showed decreased functional connectivity in the bilateral posterior cingulate gyrus, but showed greater functional connectivity in the right transverse temporal gyrus and left middle temporal gyrus. The healthy control group also showed greater activation in the cerebellum compared to the SPD group. These findings suggest that DMN functional connectivity, particularly that involving cognitive or emotional regulation, is altered in SPD subjects, and thus may be helpful in studying schizophrenia.

  15. Connecting multimodality in human communication

    Directory of Open Access Journals (Sweden)

    Christina eRegenbogen

    2013-11-01

    Full Text Available A successful reciprocal evaluation of social signals serves as a prerequisite for social coherence and empathy. In a previous fMRI study we studied naturalistic communication situations by presenting video clips to our participants and recording their behavioral responses regarding empathy and its components. In two conditions, all three channels transported congruent emotional or neutral information, respectively. Three conditions selectively presented two emotional channels and one neutral channel and were thus bimodally emotional. We reported channel-specific emotional contributions in modality-related areas, elicited by dynamic video clips with varying combinations of emotionality in facial expressions, prosody, and speech content. However, to better understand the underlying mechanisms accompanying a naturalistically displayed human social interaction in some key regions that presumably serve as specific processing hubs for facial expressions, prosody, and speech content, we pursued a reanalysis of the data. In addition to this specificity of these regions to information channels we demonstrated that they were also sensitive to variations of the respective emotional content.Here, we focused on two different descriptions of temporal characteristics within these three modality-related regions (right fusiform gyrus (FFG, left auditory cortex (AC, left angular gyrus (AG and left dorsomedial prefrontal cortex (dmPFC. By means of a finite impulse response (FIR analysis within each of the three regions we examined the post-stimulus time-courses as a description of the temporal characteristics of the BOLD response during the video clips. Second, effective connectivity between these areas and the left dmPFC was analyzed using dynamic causal modeling (DCM in order to describe condition-related modulatory influences on the coupling between these regions. The FIR analysis showed initially diminished activation in bimodally emotional conditions but

  16. Proof patterns

    CERN Document Server

    Joshi, Mark

    2015-01-01

    This innovative textbook introduces a new pattern-based approach to learning proof methods in the mathematical sciences. Readers will discover techniques that will enable them to learn new proofs across different areas of pure mathematics with ease. The patterns in proofs from diverse fields such as algebra, analysis, topology and number theory are explored. Specific topics examined include game theory, combinatorics, and Euclidean geometry, enabling a broad familiarity. The author, an experienced lecturer and researcher renowned for his innovative view and intuitive style, illuminates a wide range of techniques and examples from duplicating the cube to triangulating polygons to the infinitude of primes to the fundamental theorem of algebra. Intended as a companion for undergraduate students, this text is an essential addition to every aspiring mathematician’s toolkit.

  17. Publishing Patterns in BRIC Countries: A Network Analysis

    Directory of Open Access Journals (Sweden)

    Miguel R. Guevara

    2016-07-01

    Full Text Available How similar are the publishing patterns of among Brazil, Russia, India and China (BRIC countries in comparison with other countries? This is a question that we addressed by using networks as a tool to analyze the structure of similarities and disparities between countries. We analyzed the number of publications from 2006 to 2015 that are reported by SCImago Journal and Country Rank. With this information, we created a network in order to find the closest countries to BRIC ones, and also to find communities of similar countries favoring data analysis. We found that Brazil, China and Russia are not that close to the core cluster of countries that are more diversified. In opposition, India is closer to a community of countries that are more diverse in terms of publishing patterns. Furthermore, we found that, for different network topologies, Brazil acts as a bridge to connect developing countries and that Russia practices patterns that tend to isolate it from most of the countries.

  18. Impact of the reference choice on scalp EEG connectivity estimation

    Science.gov (United States)

    Chella, Federico; Pizzella, Vittorio; Zappasodi, Filippo; Marzetti, Laura

    2016-06-01

    Objective. Several scalp EEG functional connectivity studies, mostly clinical, seem to overlook the reference electrode impact. The subsequent interpretation of brain connectivity is thus often biased by the choice of a non-neutral reference. This study aims at systematically investigating these effects. Approach. As EEG reference, we examined the vertex electrode (Cz), the digitally linked mastoids (DLM), the average reference (AVE), and the reference electrode standardization technique (REST). As a connectivity metric, we used the imaginary part of the coherency. We tested simulated and real data (eyes-open resting state) by evaluating the influence of electrode density, the effect of head model accuracy in the REST transformation, and the impact on the characterization of the topology of functional networks from graph analysis. Main results. Simulations demonstrated that REST significantly reduced the distortion of connectivity patterns when compared to AVE, Cz, and DLM references. Moreover, the availability of high-density EEG systems and an accurate knowledge of the head model are crucial elements to improve REST performance, with the individual realistic head model being preferable to the standard realistic head model. For real data, a systematic change of the spatial pattern of functional connectivity depending on the chosen reference was also observed. The distortion of connectivity patterns was larger for the Cz reference, and progressively decreased when using the DLM, the AVE, and the REST. Strikingly, we also showed that network attributes derived from graph analysis, i.e. node degree and local efficiency, are significantly influenced by the EEG reference choice. Significance. Overall, this study highlights that significant differences arise in scalp EEG functional connectivity and graph network properties, in dependence on the chosen reference. We hope that our study will convey the message that caution should be used when interpreting and comparing

  19. Evolving soils and hydrologic connectivity in semiarid hillslopes

    Science.gov (United States)

    Saco, Patricia M.

    2015-04-01

    Soil moisture availability is essential for the stability and resilience of semiarid ecosystems. In these ecosystems the amount of soil moisture available for vegetation growth and survival is intrinsically related to the way water is redistributed, that is from source to sink areas, and therefore prescribed by the hydrologic connectivity of the landscape. Recent studies have shown that hydrologic connectivity is highly dynamic and linked to the coevolution of geomorphic, soil and vegetation structures at a variety of spatial and temporal scales. This study investigates the effect of evolving soil depths on hydrologic connectivity using a modelling framework. The focus is on Australian semiarid hillslopes with patterned vegetation that result from coevolving landforms, soils, water redistribution, and vegetation patterns. We present and analyse results from simulations using a coupled landform evolution-dynamic vegetation model, which includes a soil depth evolution module and accounts for soil production and sediment erosion and deposition processes. We analyse the effect of soils depths on surface connectivity for a range of biotic (plant functional type strategies) and abiotic (slope and erodibility) conditions. The analysis shows that different plant functional types, through their varying facilitation strategies, have a profound effect on soils depths and therefore affect hydrologic connectivity and soil moisture patterns. This interplay becomes particularly important for systems that coevolve to have very shallow soils. In this case soil depth becomes the key factor prescribing surface connectivity and available soil moisture for plants, which affect the recovery of the system after disturbance. Conditions for the existence of threshold behaviour for which small perturbations can trigger a sudden increase in hydrologic connectivity, reduced soil moisture availability and decrease in productivity leading to degraded states are investigated. Critical

  20. Pattern classification

    CERN Document Server

    Duda, Richard O; Stork, David G

    2001-01-01

    The first edition, published in 1973, has become a classic reference in the field. Now with the second edition, readers will find information on key new topics such as neural networks and statistical pattern recognition, the theory of machine learning, and the theory of invariances. Also included are worked examples, comparisons between different methods, extensive graphics, expanded exercises and computer project topics. An Instructor's Manual presenting detailed solutions to all the problems in the book is available from the Wiley editorial department.

  1. Impact of acoustic coordinated reset neuromodulation on effective connectivity in a neural network of phantom sound.

    Science.gov (United States)

    Silchenko, Alexander N; Adamchic, Ilya; Hauptmann, Christian; Tass, Peter A

    2013-08-15

    Chronic subjective tinnitus is an auditory phantom phenomenon characterized by abnormal neuronal synchrony in the central auditory system. As recently shown in a proof of concept clinical trial, acoustic coordinated reset (CR) neuromodulation causes a significant relief of tinnitus symptoms combined with a significant decrease of pathological oscillatory activity in a network comprising auditory and non-auditory brain areas. The objective of the present study was to analyze whether CR therapy caused an alteration of the effective connectivity in a tinnitus related network of localized EEG brain sources. To determine which connections matter, in a first step, we considered a larger network of brain sources previously associated with tinnitus. To that network we applied a data-driven approach, combining empirical mode decomposition and partial directed coherence analysis, in patients with bilateral tinnitus before and after 12 weeks of CR therapy as well as in healthy controls. To increase the signal-to-noise ratio, we focused on the good responders, classified by a reliable-change-index (RCI). Prior to CR therapy and compared to the healthy controls, the good responders showed a significantly increased connectivity between the left primary cortex auditory cortex and the posterior cingulate cortex in the gamma and delta bands together with a significantly decreased effective connectivity between the right primary auditory cortex and the dorsolateral prefrontal cortex in the alpha band. Intriguingly, after 12 weeks of CR therapy most of the pathological interactions were gone, so that the connectivity patterns of good responders and healthy controls became statistically indistinguishable. In addition, we used dynamic causal modeling (DCM) to examine the types of interactions which were altered by CR therapy. Our DCM results show that CR therapy specifically counteracted the imbalance of excitation and inhibition. CR significantly weakened the excitatory connection

  2. Functional connectivity of pain-mediated affect regulation in Borderline Personality Disorder.

    Directory of Open Access Journals (Sweden)

    Inga Niedtfeld

    Full Text Available Affective instability and self-injurious behavior are important features of Borderline Personality Disorder. Whereas affective instability may be caused by a pattern of limbic hyperreactivity paired with dysfunctional prefrontal regulation mechanisms, painful stimulation was found to reduce affective arousal at the neural level, possibly underlying the soothing effect of pain in BPD.We used psychophysiological interactions to analyze functional connectivity of (para- limbic brain structures (i.e. amygdala, insula, anterior cingulate cortex in Borderline Personality Disorder in response to painful stimulation. Therefore, we re-analyzed a dataset from 20 patients with Borderline Personality Disorder and 23 healthy controls who took part in an fMRI-task inducing negative (versus neutral affect and subsequently applying heat pain (versus warmth perception.Results suggest an enhanced negative coupling between limbic as well as paralimbic regions and prefrontal regions, specifically with the medial and dorsolateral prefrontal cortex, when patients experienced pain in addition to emotional arousing pictures. When neutral pictures were combined with painful heat sensation, we found positive connectivity in Borderline Personality Disorder between (para-limbic brain areas and parts of the basal ganglia (lentiform nucleus, putamen, as well areas involved in self-referential processing (precuneus and posterior cingulate.We found further evidence for alterations in the emotion regulation process in Borderline Personality Disorder, in the way that pain improves the inhibition of limbic activity by prefrontal areas. This study provides new insights in pain processing in BPD, including enhanced coupling of limbic structures and basal ganglia.

  3. Analyzing the attributes of Indiana's STEM schools

    Science.gov (United States)

    Eltz, Jeremy

    "Primary and secondary schools do not seem able to produce enough students with the interest, motivation, knowledge, and skills they will need to compete and prosper in the emerging world" (National Academy of Sciences [NAS], 2007a, p. 94). This quote indicated that there are changing expectations for today's students which have ultimately led to new models of education, such as charters, online and blended programs, career and technical centers, and for the purposes of this research, STEM schools. STEM education as defined in this study is a non-traditional model of teaching and learning intended to "equip them [students] with critical thinking, problem solving, creative and collaborative skills, and ultimately establishes connections between the school, work place, community and the global economy" (Science Foundation Arizona, 2014, p. 1). Focusing on science, technology, engineering, and math (STEM) education is believed by many educational stakeholders to be the solution for the deficits many students hold as they move on to college and careers. The National Governors Association (NGA; 2011) believes that building STEM skills in the nation's students will lead to the ability to compete globally with a new workforce that has the capacity to innovate and will in turn spur economic growth. In order to accomplish the STEM model of education, a group of educators and business leaders from Indiana developed a comprehensive plan for STEM education as an option for schools to use in order to close this gap. This plan has been promoted by the Indiana Department of Education (IDOE, 2014a) with the goal of increasing STEM schools throughout Indiana. To determine what Indiana's elementary STEM schools are doing, this study analyzed two of the elementary schools that were certified STEM by the IDOE. This qualitative case study described the findings and themes from two elementary STEM schools. Specifically, the research looked at the vital components to accomplish STEM

  4. Altered intrahemispheric structural connectivity in Gilles de la Tourette syndrome

    Directory of Open Access Journals (Sweden)

    Bastian Cheng

    2014-01-01

    Full Text Available Gilles de la Tourette syndrome (GTS is a common developmental neuropsychiatric disorder characterized by tics and frequent psychiatric comorbidities, often causing significant disability. Tic generation has been linked to disturbed networks of brain areas involved in planning, controlling and execution of actions, particularly structural and functional disorders in the striatum and cortico–striato–thalamo–cortical loops. We therefore applied structural diffusion tensor imaging (DTI to characterize changes in intrahemispheric white matter connectivity in cortico-subcortical circuits engaged in motor control in 15 GTS patients without psychiatric comorbidities. White matter connectivity was analyzed by probabilistic fiber tractography between 12 predefined cortical and subcortical regions of interest. Connectivity values were combined with measures of clinical severity rated by the Yale Global Tic Severity Scale (YGTSS. GTS patients showed widespread structural connectivity deficits. Lower connectivity values were found specifically in tracts connecting the supplementary motor areas (SMA with basal ganglia (pre-SMA–putamen, SMA–putamen and in frontal cortico-cortical circuits. There was an overall trend towards negative correlations between structural connectivity in these tracts and YGTSS scores. Structural connectivity of frontal brain networks involved in planning, controlling and executing actions is reduced in adult GTS patients which is associated with tic severity. These findings are in line with the concept of GTS as a neurodevelopmental disorder of brain immaturity.

  5. Altered intrahemispheric structural connectivity in Gilles de la Tourette syndrome.

    Science.gov (United States)

    Cheng, Bastian; Braass, Hanna; Ganos, Christos; Treszl, Andras; Biermann-Ruben, Katja; Hummel, Friedhelm C; Müller-Vahl, Kirsten; Schnitzler, Alfons; Gerloff, Christian; Münchau, Alexander; Thomalla, Götz

    2014-01-01

    Gilles de la Tourette syndrome (GTS) is a common developmental neuropsychiatric disorder characterized by tics and frequent psychiatric comorbidities, often causing significant disability. Tic generation has been linked to disturbed networks of brain areas involved in planning, controlling and execution of actions, particularly structural and functional disorders in the striatum and cortico-striato-thalamo-cortical loops. We therefore applied structural diffusion tensor imaging (DTI) to characterize changes in intrahemispheric white matter connectivity in cortico-subcortical circuits engaged in motor control in 15 GTS patients without psychiatric comorbidities. White matter connectivity was analyzed by probabilistic fiber tractography between 12 predefined cortical and subcortical regions of interest. Connectivity values were combined with measures of clinical severity rated by the Yale Global Tic Severity Scale (YGTSS). GTS patients showed widespread structural connectivity deficits. Lower connectivity values were found specifically in tracts connecting the supplementary motor areas (SMA) with basal ganglia (pre-SMA-putamen, SMA-putamen) and in frontal cortico-cortical circuits. There was an overall trend towards negative correlations between structural connectivity in these tracts and YGTSS scores. Structural connectivity of frontal brain networks involved in planning, controlling and executing actions is reduced in adult GTS patients which is associated with tic severity. These findings are in line with the concept of GTS as a neurodevelopmental disorder of brain immaturity.

  6. Systematic analysis of stability patterns in plant primary metabolism.

    Directory of Open Access Journals (Sweden)

    Dorothee Girbig

    Full Text Available Metabolic networks are characterized by complex interactions and regulatory mechanisms between many individual components. These interactions determine whether a steady state is stable to perturbations. Structural kinetic modeling (SKM is a framework to analyze the stability of metabolic steady states that allows the study of the system Jacobian without requiring detailed knowledge about individual rate equations. Stability criteria can be derived by generating a large number of structural kinetic models (SK-models with randomly sampled parameter sets and evaluating the resulting Jacobian matrices. Until now, SKM experiments applied univariate tests to detect the network components with the largest influence on stability. In this work, we present an extended SKM approach relying on supervised machine learning to detect patterns of enzyme-metabolite interactions that act together in an orchestrated manner to ensure stability. We demonstrate its application on a detailed SK-model of the Calvin-Benson cycle and connected pathways. The identified stability patterns are highly complex reflecting that changes in dynamic properties depend on concerted interactions between several network components. In total, we find more patterns that reliably ensure stability than patterns ensuring instability. This shows that the design of this system is strongly targeted towards maintaining stability. We also investigate the effect of allosteric regulators revealing that the tendency to stability is significantly increased by including experimentally determined regulatory mechanisms that have not yet been integrated into existing kinetic models.

  7. Organization of anti-phase synchronization pattern in neural networks: what are the key factors?

    Directory of Open Access Journals (Sweden)

    Dong eLi

    2011-12-01

    Full Text Available Anti-phase oscillation has been widely observed in cortical neuralnetwork. Elucidating the mechanism underlying the organization ofanti-phase pattern is of significance for better understanding morecomplicated pattern formations in brain networks. In dynamicalsystems theory, the organization of anti-phase oscillation patternhas usually been considered to relate to time-delay in coupling.This is consistent to conduction delays in real neural networks inthe brain due to finite propagation velocity of action potentials.However, other structural factors in cortical neural network, suchas modular organization (connection density and the coupling types(excitatory or inhibitory, could also play an important role. Inthis work, we investigate the anti-phase oscillation patternorganized on a two-module network of either neuronal cell model orneural mass model, and analyze the impact of the conduction delaytimes, the connection densities, and coupling types. Our resultsshow that delay times and coupling types can play key roles in thisorganization. The connection densities may have an influence on thestability if an anti-phase pattern exists due to the other factors.Furthermore, we show that anti-phase synchronization of slowoscillations can be achieved with small delay times if there isinteraction between slow and fast oscillations. These results aresignificant for further understanding more realistic spatiotemporaldynamics of cortico-cortical communications.

  8. From Sequential Pattern Mining to Structured Pattern Mining:A Pattern-Growth Approach

    Institute of Scientific and Technical Information of China (English)

    Jia-Wei Han; Jian Pei; Xi-Feng Yan

    2004-01-01

    Sequential pattern mining is an important data mining problem with broad applications. However,it is also a challenging problem since the mining may have to generate or examine a combinatorially explosive number of intermediate subsequences. Recent studies have developed two major classes of sequential pattern mining methods: (1) a candidate generation-and-test approach, represented by (i) GSP, a horizontal format-based sequential pattern mining method, and (ii) SPADE, a vertical format-based method; and (2) a pattern-growth method, represented by PrefixSpan and its further extensions, such as gSpan for mining structured patterns. In this study, we perform a systematic introduction and presentation of the pattern-growth methodology and study its principles and extensions. We first introduce two interesting pattern-growth algorithms, FreeSpan and PrefixSpan, for efficient sequential pattern mining. Then we introduce gSpan for mining structured patterns using the same methodology. Their relative performance in large databases is presented and analyzed. Several extensions of these methods are also discussed in the paper, including mining multi-level, multi-dimensional patterns and mining constraint-based patterns.

  9. From Sequential Pattern Mining to Structured Pattern Mining: A Pattern-Growth Approach

    Institute of Scientific and Technical Information of China (English)

    Jia-WeiHan; JianPei; Xi-FengYan

    2004-01-01

    Sequential pattern mining is an important data mining problem with broad applications. However, it is also a challenging problem since the mining may have to generate or examine a combinatorially explosive number of intermediate subsequences. Recent studies have developed two major classes of sequential pattern mining methods: (1) a candidate generation-and-test approach, represented by (i) GSP, a horizontal format-based sequential pattern mining method, and (ii) SPADE, a vertical format-based method; and (2) a pattern-growth method, represented by PrefixSpan and its further extensions, such as gSpan for mining structured patterns. In this study, we perform a systematic introduction and presentation of the pattern-growth methodology and study its principles and extensions. We first introduce two interesting pattern-growth algorithms, FreeSpan and PrefixSpan, for efficient sequential pattern mining. Then we introduce gSpan for mining structured patterns using the same methodology. Their relative performance in large databases is presented and analyzed. Several extensions of these methods are also discussed in the paper, including mining multi-level, multi-dimensional patterns and mining constraint-based patterns.

  10. Practical lessons in remote connectivity.

    Science.gov (United States)

    Kouroubali, A.; Starren, J.; Barrows, R. C.; Clayton, P. D.

    1997-01-01

    Community Health Information Networks (CHINs) require the ability to provide computer network connections to many remote sites. During the implementation of the Washington Heights and Inwood Community Health Management Information System (WHICHIS) at the Columbia-Presbyterian Medical Center (CPMC), a number of remote connectivity issues have been encountered. Both technical and non-technical issues were significant during the installation. We developed a work-flow model for this process which may be helpful to any health care institution attempting to provide seamless remote connectivity. This model is presented and implementation lessons are discussed. PMID:9357643

  11. Framework for Connections on Facebook

    DEFF Research Database (Denmark)

    Sudzina, Frantisek

    There is a substantial amount of current information systems and marketing research focused on social networking sites, most frequently on Facebook. Often, these studies utilize available metadata on user on-line behavior, such as what links the users clicked on. In order to better understand...... behavior of Facebook users, it makes sense to investigate also whom the users connect to. It is possible to hypothesize that behavior of people, who connect only to relatives on Facebook, differs from behavior of people, who are connected only to their classmates. The paper offers a framework of Facebook...

  12. Disrupted global metastability and static and dynamic brain connectivity across individuals in the Alzheimer’s disease continuum

    Science.gov (United States)

    Córdova-Palomera, Aldo; Kaufmann, Tobias; Persson, Karin; Alnæs, Dag; Doan, Nhat Trung; Moberget, Torgeir; Lund, Martina Jonette; Barca, Maria Lage; Engvig, Andreas; Brækhus, Anne; Engedal, Knut; Andreassen, Ole A.; Selbæk, Geir; Westlye, Lars T.

    2017-01-01

    As findings on the neuropathological and behavioral components of Alzheimer’s disease (AD) continue to accrue, converging evidence suggests that macroscale brain functional disruptions may mediate their association. Recent developments on theoretical neuroscience indicate that instantaneous patterns of brain connectivity and metastability may be a key mechanism in neural communication underlying cognitive performance. However, the potential significance of these patterns across the AD spectrum remains virtually unexplored. We assessed the clinical sensitivity of static and dynamic functional brain disruptions across the AD spectrum using resting-state fMRI in a sample consisting of AD patients (n = 80) and subjects with either mild (n = 44) or subjective (n = 26) cognitive impairment (MCI, SCI). Spatial maps constituting the nodes in the functional brain network and their associated time-series were estimated using spatial group independent component analysis and dual regression, and whole-brain oscillatory activity was analyzed both globally (metastability) and locally (static and dynamic connectivity). Instantaneous phase metrics showed functional coupling alterations in AD compared to MCI and SCI, both static (putamen, dorsal and default-mode) and dynamic (temporal, frontal-superior and default-mode), along with decreased global metastability. The results suggest that brains of AD patients display altered oscillatory patterns, in agreement with theoretical premises on cognitive dynamics.

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

    Science.gov (United States)

    McCullen, Nick; Wagenknecht, Thomas

    2016-06-01

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

  14. Connectivity and synchronization of Vicsek model

    Institute of Scientific and Technical Information of China (English)

    LIU ZhiXin; GUO Lei

    2008-01-01

    The collective behavior of multi-agent systems is an important studying point for the investigation of complex systems,and a basic model of multi-agent systems is the so called Vicsek model,which possesses some key features of complex systems,such as dynamic behavior,local interaction,changing neighborhood,etc.This model looks simple,but the nonlinearly coupled relationship makes the theoretical analysis quite complicated.Jadbabaie et al.analyzed the linearized heading equations in this model and showed that all agents will synchronize eventually,provided that the neighbor graphs associated with the agents' positions satisfy a certain connectivity condition.Much subsequent research effort has been devoted to the analysis of the Vicsek model since the publication of Jadbabaie's work.However,an unresolved key problem is when such a connectivity is satisfied.This paper given a sufficient condition to guarantee the synchronization of the Vicsek model,which is imposed on the model parameters only.Moreover,some counterexamples are given to show that the connectivity of the neighbor graphs is not sufficient for synchronization of the Vicsek model if the initial headings are allowed to be in [0,2π),which reveals some fundamental differences between the Vicsek model and its linearized version.

  15. Criminologyof the future: interdisciplinary scientific connections

    Directory of Open Access Journals (Sweden)

    Antonyan Yu.M.

    2014-12-01

    Full Text Available The results of interdisciplinary scientific connections of the modern criminology conditional on the open character of this science and the necessity of its further development are given. The narrow-purpose character of criminological researches is noted: trivial subject matter; the criminologists’ lack of psychological, psychiatric, economical, historical, biological, ethnological and other knowledge; insufficiency of complex interdisciplinary works and empirical studies. Different viewpoints on the type of criminologists’ education are analyzed. That emphasizes the necessity of cooperation between criminology and other sciences, such as: sociology, demography, culturology, psychology, economics, pedagogics, psychiatry, ethnology, history, biology, political science, philosophy and others. The phenomenon of criminology is argued: it studies a “bad”, criminal, immoral person unlike other sciences (it belongs to the number of sciences which object is person. The main parameter of criminology as a science is examined – its subject which allows to distinguish it from other legal disciplines especially from criminal law. New aspects of interconnection between criminology and criminal procedure, criminalistics, the theory of investigation activity and criminal executive law are shown. The stable connections with family law, banking law, financial law and administrative law are considered. The author emphasizes the significant potential of developing criminology in its connection with nonlegal sciences: sociology, psychiatry, economics, statistics, psychology (including criminal psychology, biology and philosophy. It is noted that prospects and progress of criminology are possible only in its cooperation with other sciences.

  16. The connection-set algebra--a novel formalism for the representation of connectivity structure in neuronal network models.

    Science.gov (United States)

    Djurfeldt, Mikael

    2012-07-01

    The connection-set algebra (CSA) is a novel and general formalism for the description of connectivity in neuronal network models, from small-scale to large-scale structure. The algebra provides operators to form more complex sets of connections from simpler ones and also provides parameterization of such sets. CSA is expressive enough to describe a wide range of connection patterns, including multiple types of random and/or geometrically dependent connectivity, and can serve as a concise notation for network structure in scientific writing. CSA implementations allow for scalable and efficient representation of connectivity in parallel neuronal network simulators and could even allow for avoiding explicit representation of connections in computer memory. The expressiveness of CSA makes prototyping of network structure easy. A C+ + version of the algebra has been implemented and used in a large-scale neuronal network simulation (Djurfeldt et al., IBM J Res Dev 52(1/2):31-42, 2008b) and an implementation in Python has been publicly released.

  17. Mundtlig eksamen via Adobe Connect

    DEFF Research Database (Denmark)

    Kjær, Christopher

    2011-01-01

    I løbet af de sidste tre år har der på Syddansk Universitet (SDU) været afholdt mere end 20 mundtlige kandidatforsvar samt andre mundtlige eksaminationer via webkonferencesystemet Adobe Connect. Formålet med denne artikel er at videregive de praktiske erfaringer fra gennemførelsen af disse...... eksaminationer samt at opstille nogle hensigtsmæssige retningslinjer for dem, der ønsker at give sig i kast med mundtlig eksamination via Adobe Connect. Der indledes derfor med en generel præsentation af Adobe Connect samt de elementer ved systemet, som oftest anvendes i forbindelse med mundtlig eksamination...... mundtlige eksaminationer via Adobe Connect....

  18. THE EXISTENCE OF CONNECTING ORBITS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In this paper,using the notion of an isolating block and Conley's attractor theory,an existence criterion of trajectories connecting a pair of invariant sets of ordinary differential equations is given.

  19. Connectivity threshold for Bluetooth graphs

    CERN Document Server

    Broutin, Nicolas; Fraiman, Nicolas; Lugosi, Gábor

    2011-01-01

    We study the connectivity properties of random Bluetooth graphs that model certain "ad hoc" wireless networks. The graphs are obtained as "irrigation subgraphs" of the well-known random geometric graph model. There are two parameters that control the model: the radius $r$ that determines the "visible neighbors" of each node and the number of edges $c$ that each node is allowed to send to these. The randomness comes from the underlying distribution of data points in space and from the choices of each vertex. We prove that no connectivity can take place with high probability for a range of parameters $r, c$ and completely characterize the connectivity threshold (in $c$) for values of $r$ close the critical value for connectivity in the underlying random geometric graph.

  20. Auditory Hallucinations in Schizophrenia Are Associated with Reduced Functional Connectivity of the Temporo-Parietal Area

    NARCIS (Netherlands)

    Vercammen, Ans; Knegtering, Henderikus; den Boer, Johann A.; Liemburg, Edith J.; Aleman, Andre

    2010-01-01

    Background: Schizophrenia has been conceptualized as a disorder of integration of neural activity across distributed networks. However, the relationship between specific symptom dimensions and patterns of functional connectivity remains unclear. The current study aimed to investigate the relationshi