WorldWideScience

Sample records for brainwide neuroanatomical connectivity

  1. A proposal for a coordinated effort for the determination of brainwide neuroanatomical connectivity in model organisms at a mesoscopic scale.

    Directory of Open Access Journals (Sweden)

    Jason W Bohland

    2009-03-01

    Full Text Available In this era of complete genomes, our knowledge of neuroanatomical circuitry remains surprisingly sparse. Such knowledge is critical, however, for both basic and clinical research into brain function. Here we advocate for a concerted effort to fill this gap, through systematic, experimental mapping of neural circuits at a mesoscopic scale of resolution suitable for comprehensive, brainwide coverage, using injections of tracers or viral vectors. We detail the scientific and medical rationale and briefly review existing knowledge and experimental techniques. We define a set of desiderata, including brainwide coverage; validated and extensible experimental techniques suitable for standardization and automation; centralized, open-access data repository; compatibility with existing resources; and tractability with current informatics technology. We discuss a hypothetical but tractable plan for mouse, additional efforts for the macaque, and technique development for human. We estimate that the mouse connectivity project could be completed within five years with a comparatively modest budget.

  2. A Brain-Wide Study of Age-Related Changes in Functional Connectivity

    NARCIS (Netherlands)

    Geerligs, Linda; Renken, Remco J.; Saliasi, Emi; Maurits, Natasha M.; Lorist, Monicque M.

    2015-01-01

    Aging affects functional connectivity between brain areas, however, a complete picture of how aging affects integration of information within and between functional networks is missing. We used complex network measures, derived from a brain-wide graph, to provide a comprehensive overview of age-rela

  3. Brain-Wide Mapping of Axonal Connections: Workflow for Automated Detection and Spatial Analysis of Labeling in Microscopic Sections.

    Science.gov (United States)

    Papp, Eszter A; Leergaard, Trygve B; Csucs, Gergely; Bjaalie, Jan G

    2016-01-01

    Axonal tracing techniques are powerful tools for exploring the structural organization of neuronal connections. Tracers such as biotinylated dextran amine (BDA) and Phaseolus vulgaris leucoagglutinin (Pha-L) allow brain-wide mapping of connections through analysis of large series of histological section images. We present a workflow for efficient collection and analysis of tract-tracing datasets with a focus on newly developed modules for image processing and assignment of anatomical location to tracing data. New functionality includes automatic detection of neuronal labeling in large image series, alignment of images to a volumetric brain atlas, and analytical tools for measuring the position and extent of labeling. To evaluate the workflow, we used high-resolution microscopic images from axonal tracing experiments in which different parts of the rat primary somatosensory cortex had been injected with BDA or Pha-L. Parameters from a set of representative images were used to automate detection of labeling in image series covering the entire brain, resulting in binary maps of the distribution of labeling. For high to medium labeling densities, automatic detection was found to provide reliable results when compared to manual analysis, whereas weak labeling required manual curation for optimal detection. To identify brain regions corresponding to labeled areas, section images were aligned to the Waxholm Space (WHS) atlas of the Sprague Dawley rat brain (v2) by custom-angle slicing of the MRI template to match individual sections. Based on the alignment, WHS coordinates were obtained for labeled elements and transformed to stereotaxic coordinates. The new workflow modules increase the efficiency and reliability of labeling detection in large series of images from histological sections, and enable anchoring to anatomical atlases for further spatial analysis and comparison with other data. PMID:27148038

  4. Neuroanatomical limbic connections of the Locus coeruleus in the nonhuman primate

    OpenAIRE

    Ubero Martinez, Maria del Mar

    2016-01-01

    The present doctoral dissertation concerns the neuroanatomical organization of the LC in the primate brain; and it is more specifically focused on the limbic connections of the HF, amygdala (Amy) and PFC with the LC in order to better understand the role that this nucleus may have in cognitive processes. Rodent functional studies indicate that LC is activated by novel salient stimuli and directly modulate memory processing. This modulation likely involves connections between LC and the HF,...

  5. Tracing Neuroanatomical Connections In Vivo Using a Novel MR-Visible Compound

    OpenAIRE

    Wu, Carolyn W.-H.; Vasalatiy, Olga; Liu, Ning(Physics Department, Henan Normal University, Xinxiang, 453007, China); Wu, Haitao; Cheal, Sarah; Chen, Der-Yow; Koretsky, Alan P.; Griffiths, Gary L.; Tootell, Roger B. H.; LESLIE G. UNGERLEIDER

    2011-01-01

    Traditional studies of neuroanatomical connections require injection of tracer compounds into living brains, then histology of the post-mortem tissue. Here we describe and validate a new compound that reveals neuronal connections in vivo, using MRI. The classic anatomical tracer CTB (cholera-toxin subunit-B) was conjugated with a gadolinium-chelate to form GdDOTA-CTB. GdDOTA-CTB was injected into the primary somatosensory cortex (S1) or the olfactory pathway of rats. High-resolution MR images...

  6. Connecting a connectome to behavior: an ensemble of neuroanatomical models of C. elegans klinotaxis.

    Directory of Open Access Journals (Sweden)

    Eduardo J Izquierdo

    Full Text Available Increased efforts in the assembly and analysis of connectome data are providing new insights into the principles underlying the connectivity of neural circuits. However, despite these considerable advances in connectomics, neuroanatomical data must be integrated with neurophysiological and behavioral data in order to obtain a complete picture of neural function. Due to its nearly complete wiring diagram and large behavioral repertoire, the nematode worm Caenorhaditis elegans is an ideal organism in which to explore in detail this link between neural connectivity and behavior. In this paper, we develop a neuroanatomically-grounded model of salt klinotaxis, a form of chemotaxis in which changes in orientation are directed towards the source through gradual continual adjustments. We identify a minimal klinotaxis circuit by systematically searching the C. elegans connectome for pathways linking chemosensory neurons to neck motor neurons, and prune the resulting network based on both experimental considerations and several simplifying assumptions. We then use an evolutionary algorithm to find possible values for the unknown electrophsyiological parameters in the network such that the behavioral performance of the entire model is optimized to match that of the animal. Multiple runs of the evolutionary algorithm produce an ensemble of such models. We analyze in some detail the mechanisms by which one of the best evolved circuits operates and characterize the similarities and differences between this mechanism and other solutions in the ensemble. Finally, we propose a series of experiments to determine which of these alternatives the worm may be using.

  7. Automated Neuroanatomical Relation Extraction: A Linguistically Motivated Approach with a PVT Connectivity Graph Case Study

    Science.gov (United States)

    Gökdeniz, Erinç; Özgür, Arzucan; Canbeyli, Reşit

    2016-01-01

    Identifying the relations among different regions of the brain is vital for a better understanding of how the brain functions. While a large number of studies have investigated the neuroanatomical and neurochemical connections among brain structures, their specific findings are found in publications scattered over a large number of years and different types of publications. Text mining techniques have provided the means to extract specific types of information from a large number of publications with the aim of presenting a larger, if not necessarily an exhaustive picture. By using natural language processing techniques, the present paper aims to identify connectivity relations among brain regions in general and relations relevant to the paraventricular nucleus of the thalamus (PVT) in particular. We introduce a linguistically motivated approach based on patterns defined over the constituency and dependency parse trees of sentences. Besides the presence of a relation between a pair of brain regions, the proposed method also identifies the directionality of the relation, which enables the creation and analysis of a directional brain region connectivity graph. The approach is evaluated over the manually annotated data sets of the WhiteText Project. In addition, as a case study, the method is applied to extract and analyze the connectivity graph of PVT, which is an important brain region that is considered to influence many functions ranging from arousal, motivation, and drug-seeking behavior to attention. The results of the PVT connectivity graph show that PVT may be a new target of research in mood assessment.

  8. Neuroanatomic Fiber Orientation Maps (FOMs)

    DEFF Research Database (Denmark)

    Axer, Hubertus; Jantzen, Jan; Grässel, David;

    2002-01-01

    A new neuroanatomic method is described which allows to map the orientation of central nervous fibers in gross histological sections. Polarised light is used to calculate the angle of inclination and direction of the fibers in each pixel. Serial fiber orientation maps (FOMs) can be aligned and 3D...

  9. Application of neuroanatomical ontologies for neuroimaging data annotation

    Directory of Open Access Journals (Sweden)

    Jessica A Turner

    2010-06-01

    Full Text Available The annotation of functional neuroimaging results for data sharing and reuse is particularly challenging, due to the diversity of terminologies of neuroanatomical structures and cortical parcellation schemes. To address this challenge, we extended the Foundational Model of Anatomy Ontology (FMA to include cytoarchitectural, Brodmann area labels, and a morphological cortical labeling scheme (e.g., the part of Brodmann area 6 in the left precentral gyrus. This representation was also used to augment the neuroanatomical axis of RadLex, the ontology for clinical imaging. The resulting neuroanatomical ontology contains explicit relationships indicating which brain regions are “part of” which other regions, across cytoarchitectural and morphological labeling schemas. We annotated a large functional neuroimaging dataset with terms from the ontology and applied a reasoning engine to analyze this dataset in conjunction with the ontology, and achieved successful inferences from the most specific level (e.g., how many subjects showed activation in a sub-part of the middle frontal gyrus to more general (how many activations were found in areas connected via a known white matter tract?. In summary, we have produced a neuroanatomical ontology that harmonizes several different terminologies of neuroanatomical structures and cortical parcellation schemes. This neuranatomical ontology is publicly available as a view of FMA at the Bioportal website at http://rest.bioontology.org/bioportal/ontologies/download/10005. The ontological encoding of anatomic knowledge can be exploited by computer reasoning engines to make inferences about neuroanatomical relationships described in imaging datasets using different terminologies. This approach could ultimately enable knowledge discovery from large, distributed fMRI studies or medical record mining.

  10. Brain-wide map of projections from mice ventral subiculum.

    Science.gov (United States)

    Tang, He; Wu, Gui-Sheng; Xie, Jing; He, Xiaobin; Deng, Ke; Wang, Huadong; Xu, Fuqiang; Luo, Huai-Rong

    2016-08-26

    The hippocampal formation plays a critical role in episodic memory formation and spatial navigation. Within the hippocampus, the subiculum is considered to be a hub connecting the hippocampal formation to the remainder of the brain. There are functional differences between the dorsal and ventral part of subiculum, while the ventral subiculum (vSub) plays a role in anxiety, stress and emotion. In the present study, we examined the projection of the ventral subiculum to the whole brain in mice by using a modified herpes simplex virus 1 strain H129 with an inserted fluorescent protein gene. In our experiments, the modified H129 transits the primary-order, second-order, and third-order neuronal projections at 36-44, 52-60 and 68-76h after inoculation in mice, respectively. Our data revealed that vSub directly projects to the medial entorhinal cortex, amygdalohippocampal area, anterodorsal thalamic nucleus, medial hypothalamus, supramammillary nucleus, medial septal nucleus and adjacent diagonal band, the connections between median raphe nucleus and interpeduncular nucleus in brain stem, while ventral prefrontal cortex, laterodorsal tegmental nucleus and locus coeruleus receives second-order projections from vSub. Our data would help further understanding the functional connections of vSub with other brain regions. PMID:27422730

  11. A neuroanatomical approach to exploring organizational performance

    Directory of Open Access Journals (Sweden)

    Gillingwater, D.

    2009-01-01

    Full Text Available Insights gained from studying the human brain have begun to open up promising new areas of research in the behavioural and social sciences. Neuroscience-based principles have been incorporated into areas such as business management, economics and marketing, leading to the development of artificial neural networks, neuroeconomics, neuromarketing and, most recently, organizational cognitive neuroscience. Similarly, the brain has been used as a powerful metaphor for thinking about and analysing the nature of organizations. However, no existing approach to organizational analysis has taken advantage of contemporary neuroanatomical principles, thereby missing the opportunity to translate core neuroanatomical knowledge into other, non-related areas of research. In this essentially conceptual paper, we propose several ways in which neuroanatomical approaches could be used to enhance organizational theory, practice and research. We suggest that truly interdisciplinary and collaborative research between neuroanatomists and organizational analysts is likely to provide novel approaches to exploring and improving organizational performance.

  12. Fiber modeling and clustering based on neuroanatomical features.

    Science.gov (United States)

    Wang, Qian; Yap, Pew-Thian; Wu, Guorong; Shen, Dinggang

    2011-01-01

    DTI tractography allows unprecedented understanding of brain neural connectivity in-vivo by capturing water diffusion patterns in brain white-matter microstructures. However, tractography algorithms often output hundreds of thousands of fibers, rendering the computation needed for subsequent data analysis intractable. A remedy is to group the fibers into bundles using fiber clustering techniques. Most existing fiber clustering methods, however, rely on fiber geometrical information only by viewing fibers as curves in the 3D Euclidean space. The important neuroanatomical aspect of the fibers is mostly ignored. In this paper, neuroanatomical information is encapsulated in a feature vector called the associativity vector, which functions as the "fingerprint" for each fiber and depicts the connectivity of the fiber with respect to individual anatomies. Using the associativity vectors of fibers, we model the fibers as observations sampled from multivariate Gaussian mixtures in the feature space. An expectation-maximization clustering approach is then employed to group the fibers into 16 major bundles. Experimental results indicate that the proposed method groups the fibers into anatomically meaningful bundles, which are highly consistent across subjects. PMID:21995008

  13. BAMS neuroanatomical ontology: design and implementation

    Directory of Open Access Journals (Sweden)

    Mihail Bota

    2008-05-01

    Full Text Available We describe in this paper the structure and main features of a domain specific ontology for neuroscience, the BAMS Neuroanatomical Ontology. The ontology includes a complete set of concepts that describe the parts of the rat nervous system, a growing set of concepts that describe neuron populations identified in different brain regions, and relationships between concepts. The ontology is linked with a complex representation of structural and physiological variables used to classify neurons, which is encoded in BAMS. BAMS Neuroanatomical Ontology is accessible on the web and includes an interface that allows browsing terms, viewing criteria for classification, and accessing associated information.

  14. Visible rodent brain-wide networks at single-neuron resolution

    Directory of Open Access Journals (Sweden)

    Jing eYuan

    2015-05-01

    Full Text Available There are some unsolvable fundamental questions, such as cell type classification, neural circuit tracing and neurovascular coupling, though great progresses are being made in neuroscience. Because of the structural features of neurons and neural circuits, the solution of these questions needs us to break through the current technology of neuroanatomy for acquiring the exactly fine morphology of neuron and vessels and tracing long-distant circuit at axonal resolution in the whole brain of mammals. Combined with fast-developing labeling techniques, efficient whole-brain optical imaging technology emerging at the right moment presents a huge potential in the structure and function research of specific-function neuron and neural circuit. In this review, we summarize brain-wide optical tomography techniques, review the progress on visible brain neuronal/vascular networks benefit from these novel techniques, and prospect the future technical development.

  15. Neuroanatomical Spatial Patterns in Turner Syndrome

    OpenAIRE

    Marzelli, Matthew J.; Hoeft, Fumiko; Hong, David S.; Reiss, Allan L.

    2010-01-01

    Turner syndrome (TS) is a highly prevalent genetic condition caused by partial or complete absence of one X-chromosome in a female and is associated with a lack of endogenous estrogen during development secondary to gonadal dysgenesis. Prominent cognitive weaknesses in executive and visuospatial function in the context of normal overall IQ also occur in affected individuals. Previous neuroimaging studies of TS point to a profile of neuroanatomical variation relative to age and sex matched con...

  16. BAMS Neuroanatomical Ontology: Design and Implementation

    OpenAIRE

    Mihail Bota; Swanson, Larry W.

    2008-01-01

    We describe in this paper the structure and main features of a domain specific ontology for neuroscience, the BAMS Neuroanatomical Ontology. The ontology includes a complete set of concepts that describe the parts of the rat nervous system, a growing set of concepts that describe neuron populations identified in different brain regions, and relationships between concepts. The ontology is linked with a complex representation of structural and physiological variables used to classify neurons, w...

  17. A half century of experimental neuroanatomical tracing

    OpenAIRE

    Lanciego, J.L. (José Luis); Wouterlood, F.G.

    2011-01-01

    Most of our current understanding of brain function and dysfunction has its firm base in what is so elegantly called the 'anatomical substrate', i.e. the anatomical, histological, and histochemical domains within the large knowledge envelope called 'neuroscience' that further includes physiological, pharmacological, neurochemical, behavioral, genetical and clinical domains. This review focuses mainly on the anatomical domain in neuroscience. To a large degree neuroanatomical tract-tracing met...

  18. High-throughput mapping of brain-wide activity in awake and drug-responsive vertebrates.

    Science.gov (United States)

    Lin, Xudong; Wang, Shiqi; Yu, Xudong; Liu, Zhuguo; Wang, Fei; Li, Wai Tsun; Cheng, Shuk Han; Dai, Qiuyun; Shi, Peng

    2015-02-01

    The reconstruction of neural activity across complete neural circuits, or brain activity mapping, has great potential in both fundamental and translational neuroscience research. Larval zebrafish, a vertebrate model, has recently been demonstrated to be amenable to whole brain activity mapping in behaving animals. Here we demonstrate a microfluidic array system ("Fish-Trap") that enables high-throughput mapping of brain-wide activity in awake larval zebrafish. Unlike the commonly practiced larva-processing methods using a rigid gel or a capillary tube, which are laborious and time-consuming, the hydrodynamic design of our microfluidic chip allows automatic, gel-free, and anesthetic-free processing of tens of larvae for microscopic imaging with single-cell resolution. Notably, this system provides the capability to directly couple pharmaceutical stimuli with real-time recording of neural activity in a large number of animals, and the local and global effects of pharmacoactive drugs on the nervous system can be directly visualized and evaluated by analyzing drug-induced functional perturbation within or across different brain regions. Using this technology, we tested a set of neurotoxin peptides and obtained new insights into how to exploit neurotoxin derivatives as therapeutic agents. The novel and versatile "Fish-Trap" technology can be readily unitized to study other stimulus (optical, acoustic, or physical) associated functional brain circuits using similar experimental strategies.

  19. The cognitive and neuroanatomical correlates of multitasking.

    Science.gov (United States)

    Burgess, P W; Veitch, E; de Lacy Costello, A; Shallice, T

    2000-01-01

    Patients who show the "strategy application disorder" can show deficits restricted to situations requiring multitasking, but the precise neuroanatomical and cognitive correlates of this problem have been rarely investigated. In this study, 60 people with circumscribed cerebral lesions and 60 age- and IQ-matched controls were given a multitasking procedure which allowed consideration of the relative contributions of task learning and remembering, planning, plan-following and remembering one's actions to multitasking performance. Lesions to the left posterior cingulate and forceps major regions gave deficits on all measures except planning. Remembering task contingencies after a delay was also affected by lesions in the region of the left anterior cingulate, and rule-breaking and failures of task switching were additionally found in people with lesions affecting the medial and more polar aspects of Brodmann's areas 8, 9 and especially 10. Planning deficits were associated with lesions to the right dorsolateral prefrontal cortex (RDLPFC). A theory of the relationships between the cognitive constructs underpinning multitasking was tested using structural equation modelling. The results suggest that there are three primary constructs that support multitasking: retrospective memory, prospective memory, and planning, with the second two drawing upon the products of the first. It is tentatively suggested that the left anterior and posterior cingulates together play some part in the retrospective memory demands, while the prospective memory and planning components make demands on processes supported by the left areas 8, 9 and 10 and the RDLPFC respectively.

  20. Neuroanatomical and Neurochemical Basis of Impulsivity

    Directory of Open Access Journals (Sweden)

    Kemal Yazici

    2010-08-01

    tis paradigm, the tendency to prefer small immediate rewards over larger, more delayed reinforcers is measured. İmpulsive choice is defined by a greater tendency to value or choose smaller, more immediate reinforcers. Impulsivity is a multi-faceted behaviour. This behaviour may be studied by subdividing it into different processes neuroanatomically and neurochemically. Neuroanatomical data support the suggestion that behavioral disinhibition (impulsive action / motoric impulsivity and delay-discounting (impulsive choice / decision making differ in the degree to which various components of frontostriatal loops are implicated in their regulation. The dorsal prefrontal cortex does not appear to be involved in mediating impulsive choice, yet does have some role in regulating inhibitory processes. In contrast, there appears to be a pronounced role for the orbitofrontal cortex and basolateral amygdala in controlling impulsive choice. Other structures, however, such as the nucleus accumbens and subthalamic nucleus may be common to both circuits. From the neurochemical perspective, dopamine system and dopamine- 2 (D2 receptors in particular, seems to be closely involved in making impulsive choice. When the noradrenaline system does not function optimally, it might contribute to increased impulsivity. Serotonin might act upon prefrontal cortex to decrease impulsive choices. Interactions between the serotonin and the dopamine systems are important in the regulation of impulsive behaviour. It is possible that various receptor subtypes of the serotonin system may exert differing and even contrasting effects on impulsive behaviour. Although it is very informative to study neurotransmitter systems separately, it should be kept in mind that there are very intimate interactions between the neurotransmitter systems mentioned above. Based on the fact that impulsivity is regulated through multiple neurotransmitters and even more receptors, one may suggest that pharmacotherapy of

  1. Interactive exploration of neuroanatomical meta-spaces

    Directory of Open Access Journals (Sweden)

    Shantanu H Joshi

    2009-11-01

    Full Text Available Large-archives of neuroimaging data present many opportunities for re-analysis and mining that can lead to new findings of use in basic research or in the characterization of clinical syndromes. However, interaction with such archives tends to be driven textually, based on subject or image volume meta-data, not the actual neuroanatomical morphology itself, for which the imaging was performed to measure. What is needed is a content-driven approach for examining not only the image content itself but to explore brains that are anatomically similar, and identifying patterns embedded within entire sets of neuroimaging data. With the aim of visual navigation of large- scale neurodatabases, we introduce the concept of brain meta-spaces. The meta-space encodes pair-wise dissimilarities between all individuals in a population and shows the relationships between brains as a navigable framework for exploration. We employ multidimensional scaling (MDS to implement meta-space processing for a new coordinate system that distributes all data points (brain surfaces in a common frame of reference, with anatomically similar brain data located near each other. To navigate within this derived meta-space, we have developed a fully interactive 3D visualization environment that allows users to examine hundreds of brains simultaneously, visualize clusters of brains with similar characteristics, zoom in on particular instances, and examine the surface topology of an individual brain's surface in detail. The visualization environment not only displays the dissimilarities between brains, but also renders complete surface representations of individual brain structures, allowing an instant 3D view of the anatomies, as well as their differences.

  2. Cognitive Consilience: Primate Non-Primary Neuroanatomical Circuits Underlying Cognition

    OpenAIRE

    Soren Van Hout Solari; Rich Martin Stoner

    2011-01-01

    Interactions between the cerebral cortex, thalamus, and basal ganglia form the basis of cognitive information processing in the mammalian brain. Understanding the principles of neuroanatomical organization in these structures is critical to understanding the functions they perform and ultimately how the human brain works. We have manually distilled and synthesized hundreds of primate neuroanatomy facts into a single interactive visualization. The resulting picture represents the fundamental n...

  3. The NeuARt II system: a viewing tool for neuroanatomical data based on published neuroanatomical atlases

    Directory of Open Access Journals (Sweden)

    Cheng Wei-Cheng

    2006-12-01

    Full Text Available Abstract Background Anatomical studies of neural circuitry describing the basic wiring diagram of the brain produce intrinsically spatial, highly complex data of great value to the neuroscience community. Published neuroanatomical atlases provide a spatial framework for these studies. We have built an informatics framework based on these atlases for the representation of neuroanatomical knowledge. This framework not only captures current methods of anatomical data acquisition and analysis, it allows these studies to be collated, compared and synthesized within a single system. Results We have developed an atlas-viewing application ('NeuARt II' in the Java language with unique functional properties. These include the ability to use copyrighted atlases as templates within which users may view, save and retrieve data-maps and annotate them with volumetric delineations. NeuARt II also permits users to view multiple levels on multiple atlases at once. Each data-map in this system is simply a stack of vector images with one image per atlas level, so any set of accurate drawings made onto a supported atlas (in vector graphics format could be uploaded into NeuARt II. Presently the database is populated with a corpus of high-quality neuroanatomical data from the laboratory of Dr Larry Swanson (consisting 64 highly-detailed maps of PHAL tract-tracing experiments, made up of 1039 separate drawings that were published in 27 primary research publications over 17 years. Herein we take selective examples from these data to demonstrate the features of NeuArt II. Our informatics tool permits users to browse, query and compare these maps. The NeuARt II tool operates within a bioinformatics knowledge management platform (called 'NeuroScholar' either as a standalone or a plug-in application. Conclusion Anatomical localization is fundamental to neuroscientific work and atlases provide an easily-understood framework that is widely used by neuroanatomists and non

  4. Neuroanatomical voxel-based profile of schizophrenia and bipolar disorder.

    Science.gov (United States)

    Maggioni, E; Bellani, M; Altamura, A C; Brambilla, P

    2016-08-01

    Although schizophrenia (SCZ) and bipolar disorder (BD) share elements of pathology (Ellison-Wright and Bullmore, 2009), the neural mechanisms underlying these disorders are still under investigation. Up until now, many neuroimaging studies investigated the brain structural differences of SCZ and BD compared with healthy controls (HC), trying to identify the possible neuroanatomical markers for the two disorders. However, just a few studies focused on the brain structural changes between the two diagnoses. The present review summarises the findings of the voxel-based grey matter (GM) comparisons between SCZ and BD, with the objective to highlight the possible consistent anatomical differences between the two disorders. While the comparisons between patients and HC highlighted overlapping areas of GM reduction in insula and anterior cingulate cortex, the SCZ-BD comparisons suggest the presence of more generalised GM deficits in SCZ compared with BD. Indeed, in a number of studies, SCZ patients showed lower GM volumes than BD patients in fronto-temporal cortex, thalamus, hippocampus and amygdala. Conversely, only a couple of studies reported GM deficits in BD compared with SCZ, both at the level of cerebellum. In summary, the two disorders exhibit both common and specific neuroanatomical characteristics, whose knowledge is mandatory to develop innovative diagnostic and treatment strategies. PMID:27095442

  5. Cognitive consilience: Primate non-primary neuroanatomical circuits underlying cognition

    Directory of Open Access Journals (Sweden)

    Soren Van Hout Solari

    2011-12-01

    Full Text Available Interactions between the cerebral cortex, thalamus, and basal ganglia form the basis ofcognitive information processing in the mammalian brain. Understanding the principles ofneuroanatomical organization in these structures is critical to understanding the functions theyperform and ultimately how the human brain works. We have manually distilled and synthesizedhundreds of primate neuroanatomy facts into a single interactive visualization. The resultingpicture represents the fundamental neuroanatomical blueprint upon which cognitive functionsmust be implemented. Within this framework we hypothesize and detail 7 functional circuitscorresponding to psychological perspectives on the brain: consolidated long-term declarativememory, short-term declarative memory, working memory/information processing, behavioralmemory selection, behavioral memory output, cognitive control, and cortical information flow regulation. Each circuit is described in terms of distinguishable neuronal groups including thecerebral isocortex (9 pyramidal neuronal groups, parahippocampal gyrus and hippocampus,thalamus (4 neuronal groups, basal ganglia (7 neuronal groups, metencephalon, basal forebrainand other subcortical nuclei. We focus on neuroanatomy related to primate non-primary corticalsystems to elucidate the basis underlying the distinct homotypical cognitive architecture. To dis-play the breadth of this review, we introduce a novel method of integrating and presenting datain multiple independent visualizations: an interactive website (www.cognitiveconsilience.comand standalone iPhone and iPad applications. With these tools we present a unique, annotatedview of neuroanatomical consilience (integration of knowledge.

  6. Invertebrate neurophylogeny: suggested terms and definitions for a neuroanatomical glossary

    Directory of Open Access Journals (Sweden)

    Müller Carsten HG

    2010-11-01

    Full Text Available Abstract Background Invertebrate nervous systems are highly disparate between different taxa. This is reflected in the terminology used to describe them, which is very rich and often confusing. Even very general terms such as 'brain', 'nerve', and 'eye' have been used in various ways in the different animal groups, but no consensus on the exact meaning exists. This impedes our understanding of the architecture of the invertebrate nervous system in general and of evolutionary transformations of nervous system characters between different taxa. Results We provide a glossary of invertebrate neuroanatomical terms with a precise and consistent terminology, taxon-independent and free of homology assumptions. This terminology is intended to form a basis for new morphological descriptions. A total of 47 terms are defined. Each entry consists of a definition, discouraged terms, and a background/comment section. Conclusions The use of our revised neuroanatomical terminology in any new descriptions of the anatomy of invertebrate nervous systems will improve the comparability of this organ system and its substructures between the various taxa, and finally even lead to better and more robust homology hypotheses.

  7. The neuroanatomical delineation of agentic and affiliative extraversion.

    Science.gov (United States)

    Grodin, Erica N; White, Tara L

    2015-06-01

    Extraversion is a fascinating personality dimension that consists of two major components, agentic extraversion and affiliative extraversion. Agentic extraversion involves incentive motivation and is expressed as a tendency toward assertiveness, persistence, and achievement. Affiliative extraversion involves the positive emotion of social warmth and is expressed as a tendency toward amicability, gregariousness, and affection. Here we investigate the neuroanatomical correlates of the personality traits of agentic and affiliative extraversion using the Multidimensional Personality Questionnaire Brief Form, structural magnetic resonance imaging, and voxel-based morphometry in a sample of 83 healthy adult volunteers. We found that trait agentic extraversion and trait affiliative extraversion were each positively associated with the volume of the medial orbitofrontal cortex bilaterally (t's ≥ 2.03, r's ≥ .23, p's < .05). Agentic extraversion was specifically and positively related to the volume of the left parahippocampal gyrus (t = 4.08, r = .21, p < .05), left cingulate gyrus (t = 4.75, r = .28, p < .05), left caudate (t = 4.29, r = .24, p < .05), and left precentral gyrus (t = 4.00, r = .18, p < .05) in males and females, and the volume of the right nucleus accumbens in males (t = 2.92, r = .20, p < .05). Trait affiliative extraversion was not found to be associated with additional regions beyond the medial orbitofrontal cortex. The findings provide the first evidence of a neuroanatomical dissociation between the personality traits of agentic and affiliative extraversion in healthy adults. PMID:25712871

  8. Functional neuroanatomical evidence for the double-deficit hypothesis of developmental dyslexia.

    Science.gov (United States)

    Norton, Elizabeth S; Black, Jessica M; Stanley, Leanne M; Tanaka, Hiroko; Gabrieli, John D E; Sawyer, Carolyn; Hoeft, Fumiko

    2014-08-01

    The double-deficit hypothesis of dyslexia posits that both rapid naming and phonological impairments can cause reading difficulties, and that individuals who have both of these deficits show greater reading impairments compared to those with a single deficit. Despite extensive behavioral research, the brain basis of poor reading with a double-deficit has never been investigated. The goal of the study was to evaluate the double-deficit hypothesis using functional MRI. Activation patterns during a printed word rhyme judgment task in 90 children with a wide range of reading abilities showed dissociation between brain regions that were sensitive to phonological awareness (left inferior frontal and inferior parietal regions) and rapid naming (right cerebellar lobule VI). More specifically, the double-deficit group showed less activation in the fronto-parietal reading network compared to children with only a deficit in phonological awareness, who in turn showed less activation than the typically-reading group. On the other hand, the double-deficit group showed less cerebellar activation compared to children with only a rapid naming deficit, who in turn showed less activation than the typically-reading children. Functional connectivity analyses revealed that bilateral prefrontal regions were key for linking brain regions associated with phonological awareness and rapid naming, with the double-deficit group being the most aberrant in their connectivity. Our study provides the first functional neuroanatomical evidence for the double-deficit hypothesis of developmental dyslexia.

  9. Neuroanatomical, genetic and neurochemical aspects of infantile autism

    Directory of Open Access Journals (Sweden)

    Gerhant, Aneta

    2013-12-01

    Full Text Available Infantile autism is a neurodevelopmental disorder characterized by impairments in communication, reciprocal social interaction and restricted repetitive behaviors or interests. Although the cause of these disorders is not yet known, studies strongly suggest a genetic basis with a complex mode of inheritance. The etiopathogenetic processes of autism are extremely complex, which is reflected in the varying course and its symptomatology. Trajectories of brain development and volumes of its structures are aberrant in autistic patients. It is suggested that disturbances in sertotoninergic, gabaergic, glutaminergic, cholinergic and dopaminergic neurotransmission can be responsible for symptoms of autism as well as can disturb the development of the young brain. The objective of this article is to present the results of reasearch on neuroanatomical, neurochemical and genetic aspects of autism.

  10. Neuroanatomical Evidence in Support of the Bilingual Advantage Theory.

    Science.gov (United States)

    Olulade, O A; Jamal, N I; Koo, D S; Perfetti, C A; LaSasso, C; Eden, G F

    2016-07-01

    The "bilingual advantage" theory stipulates that constant selection and suppression between 2 languages results in enhanced executive control (EC). Behavioral studies of EC in bilinguals have employed wide-ranging tasks and report some conflicting results. To avoid concerns about tasks, we employed a different approach, measuring gray matter volume (GMV) in adult bilinguals, reasoning that any EC-associated benefits should manifest as relatively greater frontal GMV. Indeed, Spanish-English-speaking bilinguals exhibited greater bilateral frontal GMV compared with English-speaking monolinguals. Was this observation attributable to the constant selection and inhibition of 2 spoken languages? To answer this question, we drew on bimodal bilinguals of American Sign Language (ASL) and English who, unlike unimodal bilinguals, can simultaneously use both languages and have been shown not to possess the EC advantage. In this group, there was no greater GMV when compared with monolinguals. Together these results provide neuroanatomical evidence in support of the bilingual advantage theory. PMID:26184647

  11. Converging evidence for the neuroanatomic basis of combinatorial semantics in the angular gyrus.

    Science.gov (United States)

    Price, Amy R; Bonner, Michael F; Peelle, Jonathan E; Grossman, Murray

    2015-02-18

    Human thought and language rely on the brain's ability to combine conceptual information. This fundamental process supports the construction of complex concepts from basic constituents. For example, both "jacket" and "plaid" can be represented as individual concepts, but they can also be integrated to form the more complex representation "plaid jacket." Although this process is central to the expression and comprehension of language, little is known about its neural basis. Here we present evidence for a neuroanatomic model of conceptual combination from three experiments. We predicted that the highly integrative region of heteromodal association cortex in the angular gyrus would be critical for conceptual combination, given its anatomic connectivity and its strong association with semantic memory in functional neuroimaging studies. Consistent with this hypothesis, we found that the process of combining concepts to form meaningful representations specifically modulates neural activity in the angular gyrus of healthy adults, independent of the modality of the semantic content integrated. We also found that individual differences in the structure of the angular gyrus in healthy adults are related to variability in behavioral performance on the conceptual combination task. Finally, in a group of patients with neurodegenerative disease, we found that the degree of atrophy in the angular gyrus is specifically related to impaired performance on combinatorial processing. These converging anatomic findings are consistent with a critical role for the angular gyrus in conceptual combination.

  12. [Prospective memory - concepts, methods of assessment, neuroanatomical bases and its deficits in mental disorders].

    Science.gov (United States)

    Wiłkość, Monika; Izdebski, Paweł; Zajac-Lamparska, Ludmiła

    2013-01-01

    In the last two decades of the last century there has been a shift in the studies on memory. In psychology of memory the criticism of the laboratory approach resulted in development of the ecological approach. One of the effects of this change was to initiate researches on memory that includes plans for the future, which has resulted in the distinction of the concept of prospective memory. Prospective memory is used in many aspects of everyday life. It deals with remembering intentions and plans, it is connected with remembering about specific task or activity in the future. There are three types of PM: event-based prospective memory, time-based prospective memory and activity-based prospective memory. Current research in this field have already established its own paradigm and tools measuring PM and there is still increasing scientific interest in this issue. Prospective memory assessment may be carried out in various ways. Among them, the most frequently used are: a) questionnaires, b) psychological tests, c) experimental procedures. Within the latter, the additional distinction can be introduced for: the experiments conducted under natural conditions and the laboratory procedures. In Polish literature, there are only a few articles on PM. The aim of this work is to review studies on assessment methods of PM. Its neuroanatomical bases and its functioning in different mental disorders are analyzed. The work is aimed to focus clinicians attention on prospective memory as an area which is important for complex diagnosis of cognitive processes.

  13. Global connectivity of prefrontal cortex predicts cognitive control and intelligence

    Science.gov (United States)

    Cole, Michael W.; Yarkoni, Tal; Repovs, Grega; Anticevic, Alan; Braver, Todd S.

    2012-01-01

    Control of thought and behavior is fundamental to human intelligence. Evidence suggests a fronto-parietal brain network implements such cognitive control across diverse contexts. We identify a mechanism – global connectivity – by which components of this network might coordinate control of other networks. A lateral prefrontal cortex (LPFC) region’s activity was found to predict performance in a high control demand working memory task, and also to exhibit high global connectivity. Critically, global connectivity in this LPFC region, involving connections both within and outside the fronto-parietal network, showed a highly selective relationship with individual differences in fluid intelligence. These findings suggest LPFC is a global hub with a brain-wide influence that facilitates the ability to implement control processes central to human intelligence. PMID:22745498

  14. Knowledge synthesis with maps of neural connectivity

    Directory of Open Access Journals (Sweden)

    Marcelo eTallis

    2011-11-01

    Full Text Available This paper describes software for neuroanatomical knowledge synthesis based on high-quality neural connectivity data. This software supports a mature neuroanatomical methodology developed since the early 1990s. Over this time, the Swanson laboratory at USC has generated an account of the neural connectivity of the sub-structures of the hypothalamus, amygdala, septum, hippocampus and bed nucleus of the stria terminalis. This is based on neuroanatomical data maps drawn into a standard brain atlas by experts. In earlier work, we presented an application for visualizing and comparing anatomical macroconnections using the Swanson 3rd edition atlas as a framework for accurate registration. Here we describe major improvements to the NeuARt application based on the incorporation of a knowledge representation of experimental design. We also present improvements in the interface and features of the neuroanatomical data mapping components within a unified web-application. As a step towards developing an accurate sub-regional account of neural connectivity, we provide navigational access between the neuroanatomical data maps and a semantic representation of area-to-area connections that they support. We do so based on an approach called ’Knowledge Engineering from Experimental Design’ (KEfED model that is based on experimental variables. We have extended the underlying KEfED representation of tract-tracing experiments by incorporating the definition of a neuronanatomical data map as a measurement variable in the study design. This paper describes the software design of a web application that allows anatomical data sets to be described within a standard experimental context and thus incorporated with non-spatial data sets.

  15. Developmental Sex Differences in the Relation of Neuroanatomical Connectivity to Intelligence

    Science.gov (United States)

    Schmithorst, Vincent J.

    2009-01-01

    Recent neuroimaging research has shown sex-related differences in the relationship between brain structure and cognitive function. Anatomical studies have shown a greater reliance for cognitive function on white matter structure in adult females, and a greater reliance on gray matter structure in adult males. Functional neuroimaging studies have…

  16. Glucocorticoid mechanisms of functional connectivity changes in stress-related neuropsychiatric disorders

    OpenAIRE

    Hall, Baila S.; Moda, Rachel N.; Liston, Conor

    2014-01-01

    Stress—especially chronic, uncontrollable stress—is an important risk factor for many neuropsychiatric disorders. The underlying mechanisms are complex and multifactorial, but they involve correlated changes in structural and functional measures of neuronal connectivity within cortical microcircuits and across neuroanatomically distributed brain networks. Here, we review evidence from animal models and human neuroimaging studies implicating stress-associated changes in functional connectivity...

  17. The Neuroanatomical Correlates of Training-Related Perceptuo-Reflex Uncoupling in Dancers

    OpenAIRE

    Nigmatullina, Yuliya; Hellyer, Peter J.; Nachev, Parashkev; Sharp, David J.; Seemungal, Barry M.

    2013-01-01

    Sensory input evokes low-order reflexes and higher-order perceptual responses. Vestibular stimulation elicits vestibular-ocular reflex (VOR) and self-motion perception (e.g., vertigo) whose response durations are normally equal. Adaptation to repeated whole-body rotations, for example, ballet training, is known to reduce vestibular responses. We investigated the neuroanatomical correlates of vestibular perceptuo-reflex adaptation in ballet dancers and controls. Dancers' vestibular-reflex and ...

  18. The autism puzzle: Diffuse but not pervasive neuroanatomical abnormalities in children with ASD

    OpenAIRE

    D Sussman; R.C. Leung; V.M. Vogan; Lee, W; Trelle, S; S. Lin; D.B. Cassel; Chakravarty, M.M.; Lerch, J. P.; Anagnostou, E; Taylor, M. J.

    2015-01-01

    Autism Spectrum Disorder (ASD) is a clinically diagnosed, heterogeneous, neurodevelopmental condition, whose underlying causes have yet to be fully determined. A variety of studies have investigated either cortical, subcortical, or cerebellar anatomy in ASD, but none have conducted a complete examination of all neuroanatomical parameters on a single, large cohort. The current study provides a comprehensive examination of brain development of children with ASD between the ages of 4 and 18 year...

  19. Measuring the corpus callosum in schizophrenia: a technique with neuroanatomical and cytoarchtectural basis

    Directory of Open Access Journals (Sweden)

    Venkatasubramanian G

    2003-04-01

    Full Text Available Background: Corpus Callosum (CC abnormalities have been described in schizophrenia. Review of CC measurement methods in schizophrenia reveals inconsistency and lack of neuroanatomical basis. Aims: The aims of the study are to describe a new CC measurement method with valid a neuroanatomical and cytoarchitectural basis and to demonstrate inter-rater reliability for the same. Settings and Design: The study was performed in the National Institute of Mental Health & Neurosciences, Bangalore, India. Ours is a cross-sectional study in which both the first author and senior neuroradiologist were blind to clinical details. Material and Methods: We report a reliable, semi-automated CC measuring technique with a neuroanatomical and cytoarchitectural basis tested in a group of 16 never-treated schizophrenia patients using 1-mm thick, objectively defined midsagittal MRI section. Measurement on coded slices using scion image software ensured elimination of rater bias. Statistical Analysis Used: The statistical analysis used for assessing inter-rater reliability is intraclass correlation coefficient analysis. Results: The intraclass correlation coefficients for the CC measurements were as follows: CC Area = 0.93; Anterior CC area = 0.84; Area of body of the CC = 0.83; Area of CC isthmus = 0.65; Area of CC splenium = 0.88; maximum antero-posterior distance of CC = 0.96. Conclusion: Measurements showed good inter-rater reliability. The methodology demonstrated in our study is simple, relevant, reliable and can be used for future schizophrenia research.

  20. Functional connectivity and structural covariance between regions of interest can be measured more accurately using multivariate distance correlation.

    Science.gov (United States)

    Geerligs, Linda; Cam-Can; Henson, Richard N

    2016-07-15

    Studies of brain-wide functional connectivity or structural covariance typically use measures like the Pearson correlation coefficient, applied to data that have been averaged across voxels within regions of interest (ROIs). However, averaging across voxels may result in biased connectivity estimates when there is inhomogeneity within those ROIs, e.g., sub-regions that exhibit different patterns of functional connectivity or structural covariance. Here, we propose a new measure based on "distance correlation"; a test of multivariate dependence of high dimensional vectors, which allows for both linear and non-linear dependencies. We used simulations to show how distance correlation out-performs Pearson correlation in the face of inhomogeneous ROIs. To evaluate this new measure on real data, we use resting-state fMRI scans and T1 structural scans from 2 sessions on each of 214 participants from the Cambridge Centre for Ageing & Neuroscience (Cam-CAN) project. Pearson correlation and distance correlation showed similar average connectivity patterns, for both functional connectivity and structural covariance. Nevertheless, distance correlation was shown to be 1) more reliable across sessions, 2) more similar across participants, and 3) more robust to different sets of ROIs. Moreover, we found that the similarity between functional connectivity and structural covariance estimates was higher for distance correlation compared to Pearson correlation. We also explored the relative effects of different preprocessing options and motion artefacts on functional connectivity. Because distance correlation is easy to implement and fast to compute, it is a promising alternative to Pearson correlations for investigating ROI-based brain-wide connectivity patterns, for functional as well as structural data. PMID:27114055

  1. Functional connectivity and structural covariance between regions of interest can be measured more accurately using multivariate distance correlation.

    Science.gov (United States)

    Geerligs, Linda; Cam-Can; Henson, Richard N

    2016-07-15

    Studies of brain-wide functional connectivity or structural covariance typically use measures like the Pearson correlation coefficient, applied to data that have been averaged across voxels within regions of interest (ROIs). However, averaging across voxels may result in biased connectivity estimates when there is inhomogeneity within those ROIs, e.g., sub-regions that exhibit different patterns of functional connectivity or structural covariance. Here, we propose a new measure based on "distance correlation"; a test of multivariate dependence of high dimensional vectors, which allows for both linear and non-linear dependencies. We used simulations to show how distance correlation out-performs Pearson correlation in the face of inhomogeneous ROIs. To evaluate this new measure on real data, we use resting-state fMRI scans and T1 structural scans from 2 sessions on each of 214 participants from the Cambridge Centre for Ageing & Neuroscience (Cam-CAN) project. Pearson correlation and distance correlation showed similar average connectivity patterns, for both functional connectivity and structural covariance. Nevertheless, distance correlation was shown to be 1) more reliable across sessions, 2) more similar across participants, and 3) more robust to different sets of ROIs. Moreover, we found that the similarity between functional connectivity and structural covariance estimates was higher for distance correlation compared to Pearson correlation. We also explored the relative effects of different preprocessing options and motion artefacts on functional connectivity. Because distance correlation is easy to implement and fast to compute, it is a promising alternative to Pearson correlations for investigating ROI-based brain-wide connectivity patterns, for functional as well as structural data.

  2. Neuroanatomical distribution of mechanoreceptors in the human cadaveric shoulder capsule and labrum.

    Science.gov (United States)

    Witherspoon, Jessica W; Smirnova, Irina V; McIff, Terence E

    2014-09-01

    The distribution, location, and spatial arrangement of mechanoreceptors are important for neural signal conciseness and accuracy in proprioceptive information required to maintain functional joint stability. The glenohumeral joint capsule and labrum are mechanoreceptor-containing tissues for which the distribution of mechanoreceptors has not been determined despite the importance of these tissues in stabilizing the shoulder. More recently, it has been shown that damage to articular mechanoreceptors can result in proprioceptive deficits that may lead to recurrent instability. Awareness of mechanoreceptor distribution in the glenohumeral joint capsule and labrum may allow preservation of the mechanoreceptors during surgical treatment for shoulder instability, and in turn retain the joint's proprioceptive integrity. For this reason, we sought to develop a neuroanatomical map of the mechanoreceptors within the capsule and labrum. We postulated that the mechanoreceptors in these tissues are distributed in a unique pattern, with mechanoreceptor-scarce regions that may be more appropriate for surgical dissection. We determined the neuroanatomical distribution of mechanoreceptors and their associated fascicles in the capsule and labrum from eight human cadaver shoulder pairs using our improved gold chloride staining technique and light microscopy. A distribution pattern was consistently observed in the capsule and labrum from which we derived a neuroanatomical map. Both tissues demonstrated mechanoreceptor-dense and -scarce regions that may be considered during surgical treatment for instability. Capsular fascicles were located in the subsynovial layer, whereas labral fascicles were concentrated in the peri-core zone. The capsular fascicles presented as a lattice network and with a plexiform appearance. Fascicles within the labrum resembled a cable structure with the fascicles running in parallel. Our findings contribute to the neuroanatomical knowledge of the two

  3. Neuroanatomical circuitry associated with exploratory eye movement in schizophrenia: a voxel-based morphometric study.

    Directory of Open Access Journals (Sweden)

    Linlin Qiu

    Full Text Available Schizophrenic patients present abnormalities in a variety of eye movement tasks. Exploratory eye movement (EEM dysfunction appears to be particularly specific to schizophrenia. However, the underlying mechanisms of EEM dysfunction in schizophrenia are not clearly understood. To assess the potential neuroanatomical substrates of EEM, we recorded EEM performance and conducted a voxel-based morphometric analysis of gray matter in 33 schizophrenic patients and 29 well matched healthy controls. In schizophrenic patients, decreased responsive search score (RSS and widespread gray matter density (GMD reductions were observed. Moreover, the RSS was positively correlated with GMD in distributed brain regions in schizophrenic patients. Furthermore, in schizophrenic patients, some brain regions with neuroanatomical deficits overlapped with some ones associated with RSS. These brain regions constituted an occipito-tempro-frontal circuitry involved in visual information processing and eye movement control, including the left calcarine cortex [Brodmann area (BA 17], the left cuneus (BA 18, the left superior occipital cortex (BA 18/19, the left superior frontal gyrus (BA 6, the left cerebellum, the right lingual cortex (BA 17/18, the right middle occipital cortex (BA19, the right inferior temporal cortex (BA 37, the right dorsolateral prefrontal cortex (BA 46 and bilateral precentral gyri (BA 6 extending to the frontal eye fields (FEF, BA 8. To our knowledge, we firstly reported empirical evidence that gray matter loss in the occipito-tempro-frontal neuroanatomical circuitry of visual processing system was associated with EEM performance in schizophrenia, which may be helpful for the future effort to reveal the underlying neural mechanisms for EEM disturbances in schizophrenia.

  4. The neuroanatomical phenotype of tuberous sclerosis complex: focus on radial migration lines

    Energy Technology Data Exchange (ETDEWEB)

    Eeghen, Agnies M. van [Massachusetts General Hospital, Department of Neurology, Carol and James Herscot Center for Tuberous Sclerosis Complex, Boston, MA (United States); Erasmus Medical Centre, ENCORE, Expertise Centre for Neurodevelopmental Disorders, Department of Neuroscience, Rotterdam (Netherlands); Teran, Laura Ortiz; Johnson, Jason; Caruso, Paul [Massachusetts General Hospital, Department of Radiology, Boston, MA (United States); Pulsifer, Margaret B. [Massachusetts General Hospital, Department of Psychiatry, Psychological Assessment Center, Boston, MA (United States); Thiele, Elizabeth A. [Massachusetts General Hospital, Department of Neurology, Carol and James Herscot Center for Tuberous Sclerosis Complex, Boston, MA (United States)

    2013-08-15

    The contribution of radial migration lines (RMLs) to the neuroanatomical and neurocognitive phenotype of tuberous sclerosis complex (TSC) is unclear. The aim of this study was to perform a comprehensive evaluation of the neuroradiological phenotype of TSC, distinguishing RMLs from normal-appearing white matter (NAWM) using diffusion tensor imaging (DTI) and volumetric fluid-attenuated inversion recovery imaging. Magnetic resonance images of 30 patients with TSC were evaluated. The frequencies of RMLs, tubers, and subependymal nodules (SENs) were determined for every hemispheric lobe. Cerebellar lesions and subependymal giant cell tumors were counted. DTI metrics were obtained from the NAWM of every hemispheric lobe and from the largest RML and tuber. Analyses of variance and correlations were performed to investigate the associations between neuroanatomical characteristics and relationships between RML frequency and neurocognitive outcomes. NAWM DTI metrics were compared with measurements of 16 control patients. A mean of 47 RMLs, 27 tubers, and 10 SENs were found per patient, and the frequencies of these lesions were strongly correlated (p < 0.001). RML fractional anisotropy and mean diffusivity were strongly inversely correlated (p = 0.003). NAWM DTI metrics were similar to the controls (p = 0.26). RML frequency was strongly associated with age of seizure onset (p = 0.003), intelligence outcomes (p = 0.01), and level of autistic features (p = 0.007). A detailed neuroradiological phenotype is presented, showing that RMLs are the most frequent neuroanatomical lesion, are responsible for white matter DTI abnormalities, and are strongly associated with age of seizure onset, intelligence outcomes, and level of autistic features. (orig.)

  5. Neuroanatomía a través de casos clínicos

    OpenAIRE

    Ruiz Torner, Amparo; Teruel Martí, Vicent; Valverde Navarro, Alfonso A.; Cervera Ferri, Ana; Martínez Ricós, Joana

    2012-01-01

    Este proyecto ha sido desarrollado en el Departamento de Anatomía y Embriología Humana de la Universitat de València por los profesores Amparo Ruiz Torner que ha ejercido la coordinación, Vicent Teruel Martí, Alfonso A. Valverde Navarro, Ana Cervera Ferri y Joana Martínez Ricós Nuestro objetivo ha sido ofrecer un contexto aplicado de la Neuroanatomía, asignatura básica que se cursa en el segundo año del Grado en Medicina, de una forma amena, entretenida y asequible para el estudiante. ...

  6. The Neuroanatomical Basis of Panic Disorder and Social Phobia in Schizophrenia: A Voxel Based Morphometric Study

    Science.gov (United States)

    Picado, Marisol; Carmona, Susanna; Hoekzema, Elseline; Pailhez, Guillem; Bergé, Daniel; Mané, Anna; Fauquet, Jordi; Hilferty, Joseph; Moreno, Ana; Cortizo, Romina; Vilarroya, Oscar; Bulbena, Antoni

    2015-01-01

    Objective It is known that there is a high prevalence of certain anxiety disorders among schizophrenic patients, especially panic disorder and social phobia. However, the neural underpinnings of the comorbidity of such anxiety disorders and schizophrenia remain unclear. Our study aims to determine the neuroanatomical basis of the co-occurrence of schizophrenia with panic disorder and social phobia. Methods Voxel-based morphometry was used in order to examine brain structure and to measure between-group differences, comparing magnetic resonance images of 20 anxious patients, 20 schizophrenic patients, 20 schizophrenic patients with comorbid anxiety, and 20 healthy control subjects. Results Compared to the schizophrenic patients, we observed smaller grey-matter volume (GMV) decreases in the dorsolateral prefrontal cortex and precentral gyrus in the schizophrenic-anxiety group. Additionally, the schizophrenic group showed significantly reduced GMV in the dorsolateral prefrontal cortex, precentral gyrus, orbitofrontal cortex, temporal gyrus and angular/inferior parietal gyrus when compared to the control group. Conclusions Our findings suggest that the comorbidity of schizophrenia with panic disorder and social phobia might be characterized by specific neuroanatomical and clinical alterations that may be related to maladaptive emotion regulation related to anxiety. Even thought our findings need to be replicated, our study suggests that the identification of neural abnormalities involved in anxiety, schizophrenia and schizophrenia-anxiety may lead to an improved diagnosis and management of these conditions. PMID:25774979

  7. Neuroanatomical precursors of dyslexia identified from pre-reading through to age 11.

    Science.gov (United States)

    Clark, Kristi A; Helland, Turid; Specht, Karsten; Narr, Katherine L; Manis, Franklin R; Toga, Arthur W; Hugdahl, Kenneth

    2014-12-01

    Developmental dyslexia is a common reading disorder that negatively impacts an individual's ability to achieve literacy. Although the brain network involved in reading and its dysfunction in dyslexia has been well studied, it is unknown whether dyslexia is caused by structural abnormalities in the reading network itself or in the lower-level networks that provide input to the reading network. In this study, we acquired structural magnetic resonance imaging scans longitudinally from 27 Norwegian children from before formal literacy training began until after dyslexia was diagnosed. Thus, we were able to determine that the primary neuroanatomical abnormalities that precede dyslexia are not in the reading network itself, but rather in lower-level areas responsible for auditory and visual processing and core executive functions. Abnormalities in the reading network itself were only observed at age 11, after children had learned how to read. The findings suggest that abnormalities in the reading network are the consequence of having different reading experiences, rather than dyslexia per se, whereas the neuroanatomical precursors are predominantly in primary sensory cortices.

  8. Diversity in neuroanatomical distribution of abnormal prion protein in atypical scrapie.

    Directory of Open Access Journals (Sweden)

    Alice Nentwig

    2007-06-01

    Full Text Available Scrapie is a transmissible spongiform encephalopathy (TSE in sheep and goats. In recent years, atypical scrapie cases were identified that differed from classical scrapie in the molecular characteristics of the disease-associated pathological prion protein (PrP(sc. In this study, we analyze the molecular and neuropathological phenotype of nine Swiss TSE cases in sheep and goats. One sheep was identified as classical scrapie, whereas six sheep, as well as two goats, were classified as atypical scrapie. The latter revealed a uniform electrophoretic mobility pattern of the proteinase K-resistant core fragment of PrP(sc distinct from classical scrapie regardless of the genotype, the species, and the neuroanatomical structure. Remarkably different types of neuroanatomical PrP(sc distribution were observed in atypical scrapie cases by both western immunoblotting and immunohistochemistry. Our findings indicate that the biodiversity in atypical scrapie is larger than expected and thus impacts on current sampling and testing strategies in small ruminant TSE surveillance.

  9. Distinct Neuroanatomical Substrates and Cognitive Mechanisms of Figure Copy Performance in Alzheimer's Disease and Behavioral Variant Frontotemporal Dementia

    Science.gov (United States)

    Possin, Katherine L.; Laluz, Victor R.; Alcantar, Oscar Z.; Miller, Bruce L.; Kramer, Joel H.

    2011-01-01

    Figure copy is the most common method of visual spatial assessment in dementia evaluations, but performance on this test may be multifactorial. We examined the neuroanatomical substrates of figure copy performance in 46 patients with Alzheimer's disease (AD) and 48 patients with the behavioral variant of Frontotemporal dementia (bvFTD). A group of…

  10. Novel insights into early neuroanatomical evolution in penguins from the oldest described penguin brain endocast.

    Science.gov (United States)

    Proffitt, J V; Clarke, J A; Scofield, R P

    2016-08-01

    Digital methodologies for rendering the gross morphology of the brain from X-ray computed tomography data have expanded our current understanding of the origin and evolution of avian neuroanatomy and provided new perspectives on the cognition and behavior of birds in deep time. However, fossil skulls germane to extracting digital endocasts from early stem members of extant avian lineages remain exceptionally rare. Data from early-diverging species of major avian subclades provide key information on ancestral morphologies in Aves and shifts in gross neuroanatomical structure that have occurred within those groups. Here we describe data on the gross morphology of the brain from a mid-to-late Paleocene penguin fossil from New Zealand. This most basal and geochronologically earliest-described endocast from the penguin clade indicates that described neuroanatomical features of early stem penguins, such as lower telencephalic lateral expansion, a relatively wider cerebellum, and lack of cerebellar folding, were present far earlier in penguin history than previously inferred. Limited dorsal expansion of the wulst in the new fossil is a feature seen in outgroup waterbird taxa such as Gaviidae (Loons) and diving Procellariiformes (Shearwaters, Diving Petrels, and allies), indicating that loss of flight may not drastically affect neuroanatomy in diving taxa. Wulst enlargement in the penguin lineage is first seen in the late Eocene, at least 25 million years after loss of flight and cooption of the flight stroke for aquatic diving. Similar to the origin of avian flight, major shifts in gross brain morphology follow, but do not appear to evolve quickly after, acquisition of a novel locomotor mode. Enlargement of the wulst shows a complex pattern across waterbirds, and may be linked to sensory modifications related to prey choice and foraging strategy. PMID:26916364

  11. Neuroanatomical correlates of developmental dyscalculia: combined evidence from morphometry and tractography

    Directory of Open Access Journals (Sweden)

    Elena Rykhlevskaia

    2009-11-01

    Full Text Available Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomical basis of developmental dyscalculia (DD, a specific learning deficit with prevalence rates exceeding 5%, is poorly understood. We used structural MRI and diffusion tensor imaging (DTI to examine macro- and micro-structural impairments in 7-9 year old children with DD, compared to a group of typically developing (TD children matched on age, gender, intelligence, reading abilities and working memory capacity. Voxel-based morphometry (VBM revealed reduced grey matter (GM bilaterally in superior parietal lobule, intra-parietal sulcus, fusiform gyrus, parahippocampal gyrus and right anterior temporal cortex in children with DD. VBM analysis also showed reduced white matter (WM volume in right temporal-parietal cortex. DTI revealed reduced fractional anisotropy (FA in this WM region, pointing to significant right hemisphere micro-structural impairments. Furthermore, FA in this region was correlated with numerical operations but not verbal mathematical reasoning or word reading. Atlas-based tract mapping identified the inferior longitudinal fasciculus, inferior fronto-occipital fasciculus and caudal forceps major as key pathways impaired in DD. DTI tractography suggests that long-range WM projection fibers linking the right fusiform gyrus with temporal-parietal WM are a specific source of vulnerability in DD. Network and classification analysis suggest that DD in children may be characterized by multiple dysfunctional circuits arising from a core WM deficit. Our findings link GM and WM abnormalities in children with DD and they point to macro- and micro-structural abnormalities in right hemisphere temporal-parietal WM, and pathways associated with it, as key neuroanatomical correlates of DD.

  12. Combining fiber dissection, plastination, and tractography for neuroanatomical education: Revealing the cerebellar nuclei and their white matter connections.

    NARCIS (Netherlands)

    Arnts, H.; Kleinnijenhuis, M.; Kooloos, J.G.M.; Schepens-Franke, A.N.; Cappellen van Walsum, A.M. van

    2014-01-01

    In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpret

  13. Combining Fiber Dissection, Plastination, and Tractography for Neuroanatomical Education: Revealing the Cerebellar Nuclei and Their White Matter Connections

    Science.gov (United States)

    Arnts, Hisse; Kleinnijenhuis, Michiel; Kooloos, Jan G. M.; Schepens-Franke, Annelieke N.; van Cappellen van Walsum, Anne-Marie

    2014-01-01

    In recent years, there has been a growing interest in white matter anatomy of the human brain. With advances in brain imaging techniques, the significance of white matter integrity for brain function has been demonstrated in various neurological and psychiatric disorders. As the demand for interpretation of clinical and imaging data on white…

  14. The Effects of X Chromosome Loss on Neuroanatomical and Cognitive Phenotypes During Adolescence: a Multi-modal Structural MRI and Diffusion Tensor Imaging Study.

    Science.gov (United States)

    Xie, Sheng; Zhang, Zhixin; Zhao, Qiuling; Zhang, Jiaying; Zhong, Suyu; Bi, Yanchao; He, Yong; Pan, Hui; Gong, Gaolang

    2015-09-01

    The absence of all or part of one X chromosome in female humans causes Turner's syndrome (TS), providing a unique "knockout model" to investigate the role of the X chromosome in neuroanatomy and cognition. Previous studies have demonstrated TS-associated brain differences; however, it remains largely unknown 1) how the brain structures are affected by the type of X chromosome loss and 2) how X chromosome loss influences the brain-cognition relationship. Here, we addressed these by investigating gray matter morphology and white matter connectivity using a multimodal MRI dataset from 34 adolescent TS patients (13 mosaic and 21 nonmosaic) and 21 controls. Intriguingly, the 2 TS groups exhibited significant differences in surface area in the right angular gyrus and in white matter integrity of the left tapetum of corpus callosum; these data support a link between these brain phenotypes and the type of X chromosome loss in TS. We further showed that the X chromosome modulates specific brain-cognition relationships: thickness and surface area in multiple cortical regions are positively correlated with working-memory performance in controls but negatively in TS. These findings provide novel insights into the X chromosome effect on neuroanatomical and cognitive phenotypes and highlight the role of genetic factors in brain-cognition relationships. PMID:24770708

  15. The autism puzzle: Diffuse but not pervasive neuroanatomical abnormalities in children with ASD

    Directory of Open Access Journals (Sweden)

    D. Sussman

    2015-01-01

    Full Text Available Autism Spectrum Disorder (ASD is a clinically diagnosed, heterogeneous, neurodevelopmental condition, whose underlying causes have yet to be fully determined. A variety of studies have investigated either cortical, subcortical, or cerebellar anatomy in ASD, but none have conducted a complete examination of all neuroanatomical parameters on a single, large cohort. The current study provides a comprehensive examination of brain development of children with ASD between the ages of 4 and 18 years who are carefully matched for age and sex with typically developing controls at a ratio of one-to-two. Two hundred and ten magnetic resonance images were examined from 138 Control (116 males and 22 females and 72 participants with ASD (61 males and 11 females. Cortical segmentation into 78 brain-regions and 81,924 vertices was conducted with CIVET which facilitated a region-of-interest- (ROI- and vertex-based analysis, respectively. Volumes for the cerebellum, hippocampus, striatum, pallidum, and thalamus and many associated subregions were derived using the MAGeT Brain algorithm. The study reveals cortical, subcortical and cerebellar differences between ASD and Control group participants. Diagnosis, diagnosis-by-age, and diagnosis-by-sex interaction effects were found to significantly impact total brain volume but not total surface area or mean cortical thickness of the ASD participants. Localized (vertex-based analysis of cortical thickness revealed no significant group differences, even when age, age-range, and sex were used as covariates. Nonetheless, the region-based cortical thickness analysis did reveal regional changes in the left orbitofrontal cortex and left posterior cingulate gyrus, both of which showed reduced age-related cortical thinning in ASD. Our finding of region-based differences without significant vertex-based results likely indicates non-focal effects spanning the entirety of these regions. The hippocampi, thalamus, and globus

  16. Distinct Neuroanatomical Substrates and Cognitive Mechanisms of Figure Copy Performance in Alzheimer’s Disease and Behavioral Variant Frontotemporal Dementia

    OpenAIRE

    Possin, Katherine L.; Laluz, Victor R.; Alcantar, Oscar Z.; Bruce L. Miller; KRAMER, JOEL H.

    2010-01-01

    Figure copy is the most common method of visual spatial assessment in dementia evaluations, but performance on this test may be multifactorial. We examined the neuroanatomical substrates of figure copy performance in 46 patients with Alzheimer’s disease (AD) and 48 patients with the behavioral variant of Frontotemporal dementia (bvFTD). A group of 94 neurologically healthy controls were studied for comparison. In AD, poor figure copy correlated significantly with right parietal cortex volumes...

  17. Acupuncture Points of the Horse’s Distal Thoracic Limb: A Neuroanatomic Approach to the Transposition of Traditional Points

    Directory of Open Access Journals (Sweden)

    Lisa S. Lancaster

    2012-09-01

    Full Text Available Veterinary acupuncture charts were developed based on the concept of transpositional points whereby human acupuncture maps were adapted to animal anatomy. Transpositional acupuncture points have traditionally been placed in specific locations around the horse’s coronet and distal limb believed to be the closest approximation to the human distal limb points. Because the horse has a single digit and lacks several structures analogous to the human hand and foot, precisely transposing all of the human digital points is not anatomically possible. To date there is no published research on the effect of acupuncture treatment of the equine distal limb points. This paper presents a modified approach to equine distal limb point selection based on what is known from research on other species about the neuroanatomic method of acupuncture. A rationale is presented for modification of traditional equine ting points as well as additional points around the hoof and distal limb that do not appear in the standard textbooks of equine acupuncture. The anatomy and physiology of the equine foot likely to be affected by acupuncture are briefly reviewed. Modified neuroanatomic points are proposed that may be more accurate as transpositional points. As an example of clinical application, a neuroanatomic approach to acupuncture treatment of equine laminitis is presented.

  18. A Neuroanatomical Examination of Embodied Cognition: Semantic Generation to Action-Related Stimuli

    Directory of Open Access Journals (Sweden)

    Carrie eEsopenko

    2012-04-01

    Full Text Available The theory of embodied cognition postulates that the brain represents semantic knowledge as a function of the interaction between the body and the environment. The goal of our research was to provide a neuroanatomical examination of embodied cognition using action-related pictures and words. We used functional magnetic resonance imaging (fMRI to examine whether there were shared and/or unique regions of activation between an ecologically valid semantic generation task and a motor task in the parietal-frontocentral network (PFN, as a function of stimulus format (pictures versus words for two stimulus types (hand and foot. Unlike other methods for neuroimaging analyses involving subtractive logic or conjoint analyses, this method first isolates shared and unique regions of activation within-participants before generating an averaged map. The results demonstrated shared activation between the semantic generation and motor tasks, which was organized somatotopically in the PFN, as well as unique activation for the semantic generation tasks in proximity to the hand or foot motor cortex. We also found unique and shared regions of activation in the PFN as a function of stimulus format (pictures versus words. These results further elucidate embodied cognition in that they show that brain regions activated during actual motor movements were also activated when an individual verbally generates action-related semantic information. Disembodied cognition theories and limitations are also discussed.

  19. Neuroanatomical distribution of five semantic components of verbs: evidence from fMRI.

    Science.gov (United States)

    Kemmerer, David; Castillo, Javier Gonzalez; Talavage, Thomas; Patterson, Stephanie; Wiley, Cynthia

    2008-10-01

    The Simulation Framework, also known as the Embodied Cognition Framework, maintains that conceptual knowledge is grounded in sensorimotor systems. To test several predictions that this theory makes about the neural substrates of verb meanings, we used functional magnetic resonance imaging (fMRI) to scan subjects' brains while they made semantic judgments involving five classes of verbs-specifically, Running verbs (e.g., run, jog, walk), Speaking verbs (e.g., shout, mumble, whisper), Hitting verbs (e.g., hit, poke, jab), Cutting verbs (e.g., cut, slice, hack), and Change of State verbs (e.g., shatter, smash, crack). These classes were selected because they vary with respect to the presence or absence of five distinct semantic components-specifically, ACTION, MOTION, CONTACT, CHANGE OF STATE, and TOOL USE. Based on the Simulation Framework, we hypothesized that the ACTION component depends on the primary motor and premotor cortices, that the MOTION component depends on the posterolateral temporal cortex, that the CONTACT component depends on the intraparietal sulcus and inferior parietal lobule, that the CHANGE OF STATE component depends on the ventral temporal cortex, and that the TOOL USE component depends on a distributed network of temporal, parietal, and frontal regions. Virtually all of the predictions were confirmed. Taken together, these findings support the Simulation Framework and extend our understanding of the neuroanatomical distribution of different aspects of verb meaning. PMID:17977592

  20. Multi-task connectivity reveals flexible hubs for adaptive task control

    Science.gov (United States)

    Cole, Michael W.; Reynolds, Jeremy R.; Power, Jonathan D.; Repovs, Grega; Anticevic, Alan; Braver, Todd S.

    2013-01-01

    Extensive evidence suggests the human ability to adaptively implement a wide variety of tasks is preferentially due to the operation of a fronto-parietal brain network. We hypothesized that this network’s adaptability is made possible by ‘flexible hubs’ – brain regions that rapidly update their pattern of global functional connectivity according to task demands. We utilized recent advances in characterizing brain network organization and dynamics to identify mechanisms consistent with the flexible hub theory. We found that the fronto-parietal network’s brain-wide functional connectivity pattern shifted more than other networks’ across a variety of task states, and that these connectivity patterns could be used to identify the current task. Further, these patterns were consistent across practiced and novel tasks, suggesting reuse of flexible hub connectivity patterns facilitates adaptive (novel) task performance. Together, these findings support a central role for fronto-parietal flexible hubs in cognitive control and adaptive implementation of task demands generally. PMID:23892552

  1. The parametric, psychological, neuropsychological, and neuroanatomical properties of self and world evaluation.

    Directory of Open Access Journals (Sweden)

    Alan N Simmons

    Full Text Available BACKGROUND: As an individual moves from adolescence to adulthood, they need to form a new sense of self as their environment changes from a limited to a more expansive structure. During this critical stage in development the last dramatic steps of neural development occur and numerous psychiatric conditions begin to manifest. Currently, there is no measure that aids in the quantification of how the individual is adapting to, and conceptualizing their role in, these new structures. To fill this gap we created the Self and World Evaluation Expressions Test(SWEET. METHOD: Sixty-five young adults (20.6 years-old, 36 with a history of drug use, completed the SWEET. A factor analysis was performed on the SWEET and the resultant factors were correlated with psychological, neuropsychological, and neuroanatomical battery that included both T1-wieghted and diffusion tensor magnetic resonance imaging scans. RESULTS: WE DERIVED FOUR FACTORS: Self, Social-Emotional, Financial-Intellectual, and Spirituality. While showing limited relationships to psychological and neuropsychological measures, both white matter integrity and gray matter density showed significant relationships with SWEET factors. CONCLUSIONS: These findings suggest that while individual responses may not be indicative of psychological or cognitive processes they may relate to changes in brain structure. Several of these structures, such as the negative correlation of the affective impact of world with the dorsal anterior corpus callosum white matter integrity have been observed in psychiatric conditions (e.g., obsessive-compulsive disorder. Further longitudinal research using the SWEET may help understand the impact of dramatic shifts in self/world conceptualization and potentially link these shifts to underlying changes in brain structure.

  2. The amygdala as a neurobiological target for ghrelin in rats: neuroanatomical, electrophysiological and behavioral evidence.

    Directory of Open Access Journals (Sweden)

    Mayte Alvarez-Crespo

    Full Text Available Here, we sought to demonstrate that the orexigenic circulating hormone, ghrelin, is able to exert neurobiological effects (including those linked to feeding control at the level of the amygdala, involving neuroanatomical, electrophysiological and behavioural studies. We found that ghrelin receptors (GHS-R are densely expressed in several subnuclei of the amygdala, notably in ventrolateral (LaVL and ventromedial (LaVM parts of the lateral amygdaloid nucleus. Using whole-cell patch clamp electrophysiology to record from cells in the lateral amygdaloid nucleus, we found that ghrelin reduced the frequency of mEPSCs recorded from large pyramidal-like neurons, an effect that could be blocked by co-application of a ghrelin receptor antagonist. In ad libitum fed rats, intra-amygdala administration of ghrelin produced a large orexigenic response that lasted throughout the 4 hr of testing. Conversely, in hungry, fasted rats ghrelin receptor blockade in the amygdala significantly reduced food intake. Finally, we investigated a possible interaction between ghrelin's effects on feeding control and emotional reactivity exerted at the level of the amygdala. In rats allowed to feed during a 1-hour period between ghrelin injection and anxiety testing (elevated plus maze and open field, intra-amygdala ghrelin had no effect on anxiety-like behavior. By contrast, if the rats were not given access to food during this 1-hour period, a decrease in anxiety-like behavior was observed in both tests. Collectively, these data indicate that the amygdala is a valid target brain area for ghrelin where its neurobiological effects are important for food intake and for the suppression of emotional (anxiety-like behaviors if food is not available.

  3. Neuroanatomical Correlates of Recognizing Face Expressions in Mild Stages of Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    Laurie-Anne Sapey-Triomphe

    Full Text Available Early Alzheimer's disease can involve social disinvestment, possibly as a consequence of impairment of nonverbal communication skills. This study explores whether patients with Alzheimer's disease at the mild cognitive impairment or mild dementia stage have impaired recognition of emotions in facial expressions, and describes neuroanatomical correlates of emotion processing impairment. As part of the ongoing PACO study (personality, Alzheimer's disease and behaviour, 39 patients with Alzheimer's disease at the mild cognitive impairment or mild dementia stage and 39 matched controls completed tests involving discrimination of four basic emotions-happiness, fear, anger, and disgust-on photographs of faces. In patients, automatic volumetry of 83 brain regions was performed on structural magnetic resonance images using MAPER (multi-atlas propagation with enhanced registration. From the literature, we identified for each of the four basic emotions one brain region thought to be primarily associated with the function of recognizing that emotion. We hypothesized that the volume of each of these regions would be correlated with subjects' performance in recognizing the associated emotion. Patients showed deficits of basic emotion recognition, and these impairments were correlated with the volumes of the expected regions of interest. Unexpectedly, most of these correlations were negative: better emotional facial recognition was associated with lower brain volume. In particular, recognition of fear was negatively correlated with the volume of amygdala, disgust with pallidum, and happiness with fusiform gyrus. Recognition impairment in mild stages of Alzheimer's disease for a given emotion was thus associated with less visible atrophy of functionally responsible brain structures within the patient group. Possible explanations for this counterintuitive result include neuroinflammation, regional β-amyloid deposition, or transient overcompensation during

  4. The role of the ‘ventral’ semantic and 'dorsal' pathways in conduite d’approche: A neuroanatomically-constrained computational modelling investigation.

    Directory of Open Access Journals (Sweden)

    Taiji eUeno

    2013-08-01

    Full Text Available Ever since the 19th century, the standard model for spoken language processing has assumed two pathways for repetition - a phonological pathway and a semantic pathway - and this idea has gained further support in the last decade. First, recent in vivo tractography studies have demonstrated both the ‘dorsal’ (via arcuate fasciculus and ‘ventral’ (via extreme capsule and uncinate fasciculus pathways connecting from the primary auditory area to the speech-motor area, the latter of which passes through a brain area associated with semantic processing (anterior temporal lobe. Secondly, neuropsychological evidence for the role of semantics in repetition is conduite d’approche, a successive phonological improvement (sometimes non-improvement in aphasic patients’ response by repeating several times in succession. Crucially, conduite d’approche is observed in patients with neurological damage in/around the arcuate fasciculus. Successful conduite d’approche is especially clear for semantically-intact patients and it occurs for real words rather than for nonwords. These features have led researchers to hypothesize that the patients’ disrupted phonological output is ‘cleaned-up’ by intact lexical-semantic information before the next repetition. We tested this hypothesis using the neuroanatomically-constrained dual dorsal-ventral pathway computational model. The results showed that (a damage to the dorsal pathway impaired repetition; (b in the context of recovery, the model learned to compute a correct repetition response following the model’s own noisy speech output (i.e., successful conduite d’approche; (c this behavior was more evident for real words than nonwords; and (d activation from the ventral pathway contributed to the increased rate of successful conduite d’approche for real words. These results suggest that lexical-semantic ‘clean-up’ is key to this self-correcting mechanism, supporting the classic proposal of two

  5. A comparative neuroanatomical study of the red nucleus of the cat, macaque and human.

    Directory of Open Access Journals (Sweden)

    Satoru Onodera

    Full Text Available BACKGROUND: The human red nucleus (Nr is comparatively less well-studied than that of cats or monkeys. Given the functional importance of reticular and midbrain structures in control of movement and locomotion as well as from an evolutionary perspective, we investigated the nature and extent of any differences in Nr projections to the olivary complex in quadrupedal and bipedal species. Using neuroanatomical tract-tracing techniques we developed a "neural sheet" hypothesis allowing us to propose how rubro-olivary relations differ among the three species. METHODS AND FINDINGS: Wheat germ agglutinin-horseradish peroxidase staining supports findings that the cat's nucleus accessories medialis of Bechtrew (NB projects mainly to the lateral bend of the principal olive. We clarified boundaries among nucleus of Darkschewitsch (ND, NB and parvicellular red nucleus (pNr of the cat's neural sheet. The macaque's ND-medial accessory olivary projection is rostro-caudally organized and the dorsomedial and ventrolateral parts of the macaque's pNr may project to the principal olive's rostral and caudal dorsal lamella; in cat it projects as well to pNr. Myelin- and Nissl-stained sections show that a well-developed dorsomedial part of the human Nr consists of densely packed cells, deriving small myelinated fibers that continue into the medial central tegmental tract. CONCLUSIONS: Based on these findings we suggest there are distinct bipedal-quadrupedal differences for Nr projections to the olivary complex. We propose the Nr of cats and monkeys comprise the ND, NB and pNr in a zonal sheet-like structure, retaining clear nuclear boundaries and an isolated, well-developed mNr. The human NB may be distinguished from its more specialised ND (ND lies alongside a well-developed pNr in the human central gray. Phylogenetically, the NB may have been translocated into a roll-shaped Nr in the reticular formation, the dorsomedial portion of which might correspond to the cat

  6. Neuroanatomical asymmetries and handedness in chimpanzees (Pan troglodytes): a case for continuity in the evolution of hemispheric specialization.

    Science.gov (United States)

    Hopkins, William D

    2013-06-01

    Many historical and contemporary theorists have proposed that population-level behavioral and brain asymmetries are unique to humans and evolved as a consequence of human-specific adaptations such as language, tool manufacture and use, and bipedalism. Recent studies in nonhuman animals, notably primates, have begun to challenge this view. Here, I summarize comparative data on neuroanatomical asymmetries in the planum temporale (PT) and inferior frontal gyrus (IFG) of humans and chimpanzees, regions considered the morphological equivalents to Broca's and Wernicke's areas. I also review evidence of population-level handedness in captive and wild chimpanzees. When similar methods and landmarks are used to define the PT and IFG, humans and chimpanzees show similar patterns of asymmetry in both cortical regions, though humans show more pronounced directional biases. Similarly, there is good evidence that chimpanzees show population-level handedness, though, again, the expression of handedness is less robust compared to humans. These results stand in contrast to reported claims of significant differences in the distribution of handedness in humans and chimpanzees, and I discuss some possible explanations for the discrepancies in the neuroanatomical and behavioral data. PMID:23647534

  7. Neuroanatomical correlates of attitudes toward suicide in a large healthy sample: A voxel-based morphometric analysis.

    Science.gov (United States)

    Liu, Huijuan; Wang, Yongchao; Liu, Wei; Wei, Dongtao; Yang, Junyi; Du, Xue; Tian, Xue; Qiu, Jiang

    2016-01-01

    Previous studies have indicated that permissive attitudes toward suicide are positively associated with mental illness (e.g., depression and loneliness). Evidence suggests that there are abnormalities in the cognitive and brain functioning of suicidal patients. Nevertheless, there has been no evidence of the correlation between attitudes toward suicide and abnormal brain structure variations in healthy people. Therefore, in this study, we seek to investigate the neuroanatomical differences in healthy participants with regard to attitudes toward suicide. The results show that permissive attitudes toward suicide were significantly correlated with gray matter volume (GMV) in the left dorsolateral prefrontal cortex (DLPFC) and the left cerebellum in the large sample (n=405), which may be related to inefficient inhibitory control of negative emotion. Then, in a subset of healthy individuals with permissive attitudes (n=113), we also observed that stronger permissive attitudes toward suicide were positively related to the larger GMV in the left DLPFC and the left middle temporal gyrus (MTG), which may be associated with sensitivity of emotional feeling. Furthermore, loneliness had a mediating effect on the relation between the DLPFC volume and attitudes toward suicide. Taken together, neuroanatomical differences in healthy participants with permissive attitudes toward suicide may provide a better understanding of permissive attitudes toward suicide as a likely risk factor for suicidal behavior.

  8. 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.

  9. Voxel Scale Complex Networks of Functional Connectivity in the Rat Brain: Neurochemical State Dependence of Global and Local Topological Properties

    Directory of Open Access Journals (Sweden)

    Adam J. Schwarz

    2012-01-01

    Full Text Available Network analysis of functional imaging data reveals emergent features of the brain as a function of its topological properties. However, the brain is not a homogeneous network, and the dependence of functional connectivity parameters on neuroanatomical substrate and parcellation scale is a key issue. Moreover, the extent to which these topological properties depend on underlying neurochemical changes remains unclear. In the present study, we investigated both global statistical properties and the local, voxel-scale distribution of connectivity parameters of the rat brain. Different neurotransmitter systems were stimulated by pharmacological challenge (d-amphetamine, fluoxetine, and nicotine to discriminate between stimulus-specific functional connectivity and more general features of the rat brain architecture. Although global connectivity parameters were similar, mapping of local connectivity parameters at high spatial resolution revealed strong neuroanatomical dependence of functional connectivity in the rat brain, with clear differentiation between the neocortex and older brain regions. Localized foci of high functional connectivity independent of drug challenge were found in the sensorimotor cortices, consistent with the high neuronal connectivity in these regions. Conversely, the topological properties and node roles in subcortical regions varied with neurochemical state and were dependent on the specific dynamics of the different functional processes elicited.

  10. Prospective memory – concepts, methods of assessment, neuroanatomical bases and its deficits in mental disorders [Pamięć prospektywna – pojęcia, metody badania, podłoże neuroanatomiczne oraz jej deficyty w chorobach psychicznych

    Directory of Open Access Journals (Sweden)

    Wiłkość, Monika

    2013-04-01

    Full Text Available In the last two decades of the last century there has been a shift in the studies on memory. In psychology of memory the criticism of the laboratory approach resulted in development of the ecological approach. One of the effects of this change was to initiate researches on memory that includes plans for the future, which has resulted in the distinction of the concept of prospective memory. Prospective memory is used in many aspects of everyday life. It deals with remembering intentions and plans, it is connected with remembering about specific task or activity in the future. There are three types of PM: event-based prospective memory, time-based prospective memory and activity-based prospective memory. Current research in this field have already established its own paradigm and tools measuring PM and there is still increasing scientific interest in this issue. Prospective memory assessment may be carried out in various ways. Among them, the most frequently used are: a questionnaires, b psychological tests, c experimental procedures. Within the latter, the additional distinction can be introduced for: the experiments conducted under natural conditions and the laboratory procedures. In Polish literature, there are only a few articles on PM. The aim of this work is to review studies on assessment methods of PM. Its neuroanatomical bases and its functioning in different mental disorders are analyzed. The work is aimed to focus clinicians attention on prospective memory as an area which is important for complex diagnosis of cognitive processes.

  11. From Mimicry to Language: A Neuroanatomically Based Evolutionary Model of the Emergence of Vocal Language.

    Science.gov (United States)

    Poliva, Oren

    2016-01-01

    The auditory cortex communicates with the frontal lobe via the middle temporal gyrus (auditory ventral stream; AVS) or the inferior parietal lobule (auditory dorsal stream; ADS). Whereas the AVS is ascribed only with sound recognition, the ADS is ascribed with sound localization, voice detection, prosodic perception/production, lip-speech integration, phoneme discrimination, articulation, repetition, phonological long-term memory and working memory. Previously, I interpreted the juxtaposition of sound localization, voice detection, audio-visual integration and prosodic analysis, as evidence that the behavioral precursor to human speech is the exchange of contact calls in non-human primates. Herein, I interpret the remaining ADS functions as evidence of additional stages in language evolution. According to this model, the role of the ADS in vocal control enabled early Homo (Hominans) to name objects using monosyllabic calls, and allowed children to learn their parents' calls by imitating their lip movements. Initially, the calls were forgotten quickly but gradually were remembered for longer periods. Once the representations of the calls became permanent, mimicry was limited to infancy, and older individuals encoded in the ADS a lexicon for the names of objects (phonological lexicon). Consequently, sound recognition in the AVS was sufficient for activating the phonological representations in the ADS and mimicry became independent of lip-reading. Later, by developing inhibitory connections between acoustic-syllabic representations in the AVS and phonological representations of subsequent syllables in the ADS, Hominans became capable of concatenating the monosyllabic calls for repeating polysyllabic words (i.e., developed working memory). Finally, due to strengthening of connections between phonological representations in the ADS, Hominans became capable of encoding several syllables as a single representation (chunking). Consequently, Hominans began vocalizing and

  12. Examination of the combined effects of chondroitinase ABC, growth factors and locomotor training following compressive spinal cord injury on neuroanatomical plasticity and kinematics.

    Directory of Open Access Journals (Sweden)

    Olivier Alluin

    Full Text Available While several cellular and pharmacological treatments have been evaluated following spinal cord injury (SCI in animal models, it is increasingly recognized that approaches to address the glial scar, including the use of chondroitinase ABC (ChABC, can facilitate neuroanatomical plasticity. Moreover, increasing evidence suggests that combinatorial strategies are key to unlocking the plasticity that is enabled by ChABC. Given this, we evaluated the anatomical and functional consequences of ChABC in a combinatorial approach that also included growth factor (EGF, FGF2 and PDGF-AA treatments and daily treadmill training on the recovery of hindlimb locomotion in rats with mid thoracic clip compression SCI. Using quantitative neuroanatomical and kinematic assessments, we demonstrate that the combined therapy significantly enhanced the neuroanatomical plasticity of major descending spinal tracts such as corticospinal and serotonergic-spinal pathways. Additionally, the pharmacological treatment attenuated chronic astrogliosis and inflammation at and adjacent to the lesion with the modest synergistic effects of treadmill training. We also observed a trend for earlier recovery of locomotion accompanied by an improvement of the overall angular excursions in rats treated with ChABC and growth factors in the first 4 weeks after SCI. At the end of the 7-week recovery period, rats from all groups exhibited an impressive spontaneous recovery of the kinematic parameters during locomotion on treadmill. However, although the combinatorial treatment led to clear chronic neuroanatomical plasticity, these structural changes did not translate to an additional long-term improvement of locomotor parameters studied including hindlimb-forelimb coupling. These findings demonstrate the beneficial effects of combined ChABC, growth factors and locomotor training on the plasticity of the injured spinal cord and the potential to induce earlier neurobehavioral recovery. However

  13. Desarrollo de un espacio web de prácticas de neuroanatomía y embriología humanas

    OpenAIRE

    Peña Melián, Ángel; Pérez de Miguelsanz, Julia; Maestro de Las Casas, María del Carmen; Blanco Fernández de Valderrama, María Jose; Cabrera Parra, Walter

    2007-01-01

    Presentamos dos proyectos que se relacionan, el primero con la mejora en las prácticas de neuroanatomía para alumnos de segundo de medicina, y el segundo con la enseñanza de la embriología humana, un proyecto bastante complejo del que presentamos aquí su inicio, pero que deseamos convertirlo a medio plazo en una asignatura virtual

  14. Leptin receptor gene in the European sea bass (Dicentrarchus labrax): Cloning, phylogeny, tissue distribution and neuroanatomical organization.

    Science.gov (United States)

    Escobar, Sebastián; Rocha, Ana; Felip, Alicia; Carrillo, Manuel; Zanuy, Silvia; Kah, Olivier; Servili, Arianna

    2016-04-01

    In this study, we report the cloning of three transcripts for leptin receptor in the European sea bass, a marine teleost of economic interest. The two shortest variants, generated by different splice sites, encode all functional extracellular and intracellular domains but missed the transmembrane domain. The resulting proteins are therefore potential soluble binding proteins for leptin. The longest transcript (3605bp), termed sblepr, includes all the essential domains for binding and transduction of the signal. Thus, it is proposed as the ortholog for the human LEPR gene, the main responsible for leptin signaling. Phylogenetic analysis shows the sblepr clustered within the teleost leptin receptor group in 100% of the bootstrap replicates. The neuroanatomical localization of sblepr expressing cells has been assessed by in situ hybridization in brains of sea bass of both sexes during their first sexual maturation. At histological level, the distribution pattern of sblepr expressing cells in the brain shows no clear differences regarding sex or reproductive season. Transcripts of the sblepr have a widespread distribution throughout the forebrain and midbrain until the caudal portion of the hypothalamus. A high hybridization signal is detected in the telencephalon, preoptic area, medial basal and caudal hypothalamus and in the pituitary gland. In a more caudal region, sblepr expressing cells are identified in the longitudinal torus. The expression pattern observed for sblepr suggests that in sea bass, leptin is very likely to be involved in the control of food intake, energy reserves and reproduction. PMID:26979276

  15. Neuroanatomical relationships between FMRFamide-immunoreactive components of the nervus terminalis and the topology of olfactory bulbs in teleost fish.

    Science.gov (United States)

    D'Aniello, Biagio; Polese, Gianluca; Luongo, Luciano; Scandurra, Anna; Magliozzi, Laura; Aria, Massimo; Pinelli, Claudia

    2016-04-01

    The nervus terminalis (NT) is the most anterior of the vertebrate cranial nerves. In teleost fish, the NT runs across all olfactory components and shows high morphological variability within this taxon. We compare the anatomical distribution, average number and size of the FMRFamide-immunoreactive (ir) NT cells of fourteen teleost species with different positions of olfactory bulbs (OBs) with respect to the ventral telencephalic area. Based on the topology of the OBs, three different neuroanatomical organizations of the telencephalon can be defined, viz., fish having sessile (Type I), pseudosessile (short stalked; Type II) or stalked (Type III) OBs. Type III topology of OBs appears to be a feature associated with more basal species, whereas Types I and II occur in derived and in basal species. The displacement of the OBs is positively correlated with the peripheral distribution of the FMRFamide-ir NT cells. The number of cells is negatively correlated with the size of the cells. A dependence analysis related to the type of OB topology revealed a positive relationship with the number of cells and with the size of the cells, with Type I and II topologies of OBs showing significantly fewer cells and larger cells than Type III. A dendrogram based on similarities obtained by taking into account all variables under study, i.e., the number and size of the FMRFamide-ir NT cells and the topology of OBs, does not agree with the phylogenetic relationships amongst species, suggesting that divergent or convergent evolutionary phenomena produced the olfactory components studied.

  16. Neuroanatomical correlates of tinnitus revealed by cortical thickness analysis and diffusion tensor imaging

    International Nuclear Information System (INIS)

    Tinnitus is a poorly understood auditory perception of sound in the absence of external stimuli. Convergent evidence proposes that tinnitus perception involves brain structural alterations as part of its pathophysiology. The aim of this study is to investigate the structural brain changes that might be associated with tinnitus-related stress and negative emotions. Using high-resolution magnetic resonance imaging and diffusion tensor imaging, we investigated grey matter and white matter (WM) alterations by estimating cortical thickness measures, fractional anisotropy and mean diffusivity in 14 tinnitus subjects and 14 age- and sex-matched non-tinnitus subjects. Significant cortical thickness reductions were found in the prefrontal cortex (PFC), temporal lobe and limbic system in tinnitus subjects compared to non-tinnitus subjects. Tinnitus sufferers were found to have disrupted WM integrity in tracts involving connectivity of the PFC, temporal lobe, thalamus and limbic system. Our results suggest that such neural changes may represent neural origins for tinnitus or consequences of tinnitus and its associations. (orig.)

  17. Neuroanatomical correlates of tinnitus revealed by cortical thickness analysis and diffusion tensor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Aldhafeeri, Faten M. [The University of Liverpool, Department of Medical Imaging, School of Health Sciences, Liverpool (United Kingdom); King Khalid General Hospital, Ministry of Health, Radiology Department, Hafral-batin (Saudi Arabia); Mackenzie, Ian; Kay, Tony [Aintree University Hospitals NHS Foundation Trust, Liverpool (United Kingdom); Alghamdi, Jamaan [The University of Liverpool, Department of Medical Imaging, School of Health Sciences, Liverpool (United Kingdom); King Abdul Aziz University, Physics Department, Faculty of Sciences, Jeddah (Saudi Arabia); Sluming, Vanessa [The University of Liverpool, Department of Medical Imaging, School of Health Sciences, Liverpool (United Kingdom); Magnetic Resonance and Image Analysis Research Centre, Liverpool (United Kingdom)

    2012-08-15

    Tinnitus is a poorly understood auditory perception of sound in the absence of external stimuli. Convergent evidence proposes that tinnitus perception involves brain structural alterations as part of its pathophysiology. The aim of this study is to investigate the structural brain changes that might be associated with tinnitus-related stress and negative emotions. Using high-resolution magnetic resonance imaging and diffusion tensor imaging, we investigated grey matter and white matter (WM) alterations by estimating cortical thickness measures, fractional anisotropy and mean diffusivity in 14 tinnitus subjects and 14 age- and sex-matched non-tinnitus subjects. Significant cortical thickness reductions were found in the prefrontal cortex (PFC), temporal lobe and limbic system in tinnitus subjects compared to non-tinnitus subjects. Tinnitus sufferers were found to have disrupted WM integrity in tracts involving connectivity of the PFC, temporal lobe, thalamus and limbic system. Our results suggest that such neural changes may represent neural origins for tinnitus or consequences of tinnitus and its associations. (orig.)

  18. 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 ...... of connectivity might endure, as Capetonian politics assumes a post-apartheid structure....

  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. 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...

  1. Unraveling the multiscale structural organization and connectivity of the human brain: the role of diffusion MRI

    Directory of Open Access Journals (Sweden)

    Matteo eBastiani

    2015-06-01

    Full Text Available The structural architecture and the anatomical connectivity of the human brain show different organizational principles at distinct spatial scales. Histological staining and light microscopy techniques have been widely used in classical neuroanatomical studies to unravel brain organization. Using such techniques is a laborious task performed on 2-dimensional histological sections by skilled anatomists possibly aided by semi-automated algorithms. With the recent advent of modern magnetic resonance imaging (MRI contrast mechanisms, cortical layers and columns can now be reliably identified and their structural properties quantified post mortem. These developments are allowing the investigation of neuroanatomical features of the brain at a spatial resolution that could be interfaced with that of histology. Diffusion MRI and tractography techniques, in particular, have been used to probe the architecture of both white and gray matter in three dimensions. Combined with mathematical network analysis, these techniques are increasingly influential in the investigation of the macro-, meso- and microscopic organization of brain connectivity and anatomy, both in vivo and ex vivo. Diffusion MRI-based techniques in combination with histology approaches can therefore support the endeavor of creating multimodal atlases that take into account the different spatial scales or levels on which the brain is organized. The aim of this review is to illustrate and discuss the structural architecture and the anatomical connectivity of the human brain at different spatial scales and how recently developed diffusion MRI techniques can help investigate these.

  2. 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.

  3. 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

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

    Science.gov (United States)

    Billeh, Yazan N; Rodriguez, Alexander V; Bellesi, Michele; Bernard, Amy; de Vivo, Luisa; Funk, Chadd M; Harris, Julie; Honjoh, Sakiko; Mihalas, Stefan; Ng, Lydia; Koch, Christof; Cirelli, Chiara; Tononi, Giulio

    2016-01-01

    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

  5. 78 FR 55684 - ConnectED Workshop

    Science.gov (United States)

    2013-09-11

    ... National Telecommunications and Information Administration ConnectED Workshop AGENCY: National... in the United States to next- generation broadband. This Notice announces that the ConnectED Workshop... ConnectED Workshop will discuss the growing bandwidth needs of K-12 schools as more schools use...

  6. Discordant connections

    OpenAIRE

    Arora-Jonsson, Seema

    2009-01-01

    The importance of gender-equality and of women’s work in relation to the environment are considered to be crucial questions for development in ‘third world’ rural societies. ‘Development’ and a certain standard of welfare make these issues appear to be less urgent in a wealthier country like Sweden. In this paper I trace some of the contradictions and connections in the ways in which gender equality is conceptualised in women’s struggles vis á vis environmental issues in rural areas in Swede...

  7. Places Connected:

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    Nations Volunteer of Japanese nationality. Networks of personal ties, ideas, feelings, and material culture. By combining work on the experience of place with network historiography on migration and kinship, the paper presents a case on the function of the temporary encounter in human networks....... experience the places of Denmark and Japan temporarily integrate the national histories of these two countries in the histories of their home countries and vice versa. Thereby, I wish to offer a dynamic understanding of development history and globalization, which challenges the nationally bound histories...... experiences of place, however, when it is often the same people who experience many different places? Along with many other so-called donors in the 1950s, Denmark and Japan chose to invest in the education of own and other nationals involved in development and thereby financed personal connections between...

  8. Changes in resting neural connectivity during propofol sedation.

    Directory of Open Access Journals (Sweden)

    Emmanuel A Stamatakis

    Full Text Available The default mode network consists of a set of functionally connected brain regions (posterior cingulate, medial prefrontal cortex and bilateral parietal cortex maximally active in functional imaging studies under "no task" conditions. It has been argued that the posterior cingulate is important in consciousness/awareness, but previous investigations of resting interactions between the posterior cingulate cortex and other brain regions during sedation and anesthesia have produced inconsistent results.We examined the connectivity of the posterior cingulate at different levels of consciousness. "No task" fMRI (BOLD data were collected from healthy volunteers while awake and at low and moderate levels of sedation, induced by the anesthetic agent propofol. Our data show that connectivity of the posterior cingulate changes during sedation to include areas that are not traditionally considered to be part of the default mode network, such as the motor/somatosensory cortices, the anterior thalamic nuclei, and the reticular activating system.This neuroanatomical signature resembles that of non-REM sleep, and may be evidence for a system that reduces its discriminable states and switches into more stereotypic patterns of firing under sedation.

  9. 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.

  10. 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

  11. Using Diffusion Tractography to Predict Cortical Connection Strength and Distance: A Quantitative Comparison with Tracers in the Monkey

    DEFF Research Database (Denmark)

    Donahue, Chad J.; Sotiropoulos, Stamatios N.; Jbabdi, Saad;

    2016-01-01

    Tractography based on diffusion MRI offers the promise of characterizing many aspects of long-distance connectivity in the brain, but requires quantitative validation to assess its strengths and limitations. Here, we evaluate tractography's ability to estimate the presence and strength of connect......Tractography based on diffusion MRI offers the promise of characterizing many aspects of long-distance connectivity in the brain, but requires quantitative validation to assess its strengths and limitations. Here, we evaluate tractography's ability to estimate the presence and strength...... of connections between areas of macaque neocortex by comparing its results with published data from retrograde tracer injections. Probabilistic tractography was performed on high-quality postmortem diffusion imaging scans from two Old World monkey brains. Tractography connection weights were estimated using...... of comprehensive maps of neural connections in the brain ("connectomes"). Here, we describe methods to assess quantitatively tractography's performance in detecting interareal cortical connections and estimating connection strength by comparing it against published results using neuroanatomical tracers. We found...

  12. 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.......In the present paper we consider the allocation of cost in connection networks. Agents have connection demands in form of pairs of locations they want to be connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection demands...

  13. Brain aromatase (Cyp19A2) and estrogen receptors, in larvae and adult pejerrey fish Odontesthes bonariensis: Neuroanatomical and functional relations

    Science.gov (United States)

    Strobl-Mazzulla, P. H.; Lethimonier, C.; Gueguen, M.M.; Karube, M.; Fernandino, J.I.; Yoshizaki, G.; Patino, R.; Strussmann, C.A.; Kah, O.; Somoza, G.M.

    2008-01-01

    Although estrogens exert many functions on vertebrate brains, there is little information on the relationship between brain aromatase and estrogen receptors. Here, we report the cloning and characterization of two estrogen receptors, ?? and ??, in pejerrey. Both receptors' mRNAs largely overlap and were predominantly expressed in the brain, pituitary, liver, and gonads. Also brain aromatase and estrogen receptors were up-regulated in the brain of estradiol-treated males. In situ hybridization was performed to study in more detail, the distribution of the two receptors in comparison with brain aromatase mRNA in the brain of adult pejerrey. The estrogen receptors' mRNAs exhibited distinct but partially overlapping patterns of expression in the preoptic area and the mediobasal hypothalamus, as well as in the pituitary gland. Moreover, the estrogen receptor ??, but not ??, were found to be expressed in cells lining the preoptic recess, similarly as observed for brain aromatase. Finally, it was shown that the onset expression of brain aromatase and both estrogen receptors in the head of larvae preceded the morphological differentiation of the gonads. Because pejerrey sex differentiation is strongly influenced by temperature, brain aromatase expression was measured during the temperature-sensitive window and was found to be significantly higher at male-promoting temperature. Taken together these results suggest close neuroanatomical and functional relationships between brain aromatase and estrogen receptors, probably involved in the sexual differentiation of the brain and raising interesting questions on the origin (central or peripheral) of the brain aromatase substrate. ?? 2008 Elsevier Inc.

  14. Neuroanatomical Classification in a Population-Based Sample of Psychotic Major Depression and Bipolar I Disorder with 1 Year of Diagnostic Stability

    Directory of Open Access Journals (Sweden)

    Mauricio H. Serpa

    2014-01-01

    Full Text Available The presence of psychotic features in the course of a depressive disorder is known to increase the risk for bipolarity, but the early identification of such cases remains challenging in clinical practice. In the present study, we evaluated the diagnostic performance of a neuroanatomical pattern classification method in the discrimination between psychotic major depressive disorder (MDD, bipolar I disorder (BD-I, and healthy controls (HC using a homogenous sample of patients at an early course of their illness. Twenty-three cases of first-episode psychotic mania (BD-I and 19 individuals with a first episode of psychotic MDD whose diagnosis remained stable during 1 year of followup underwent 1.5 T MRI at baseline. A previously validated multivariate classifier based on support vector machine (SVM was employed and measures of diagnostic performance were obtained for the discrimination between each diagnostic group and subsamples of age- and gender-matched controls recruited in the same neighborhood of the patients. Based on T1-weighted images only, the SVM-classifier afforded poor discrimination in all 3 pairwise comparisons: BD-I versus HC; MDD versus HC; and BD-I versus MDD. Thus, at the population level and using structural MRI only, we failed to achieve good discrimination between BD-I, psychotic MDD, and HC in this proof of concept study.

  15. 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......In the present paper we consider the allocation of costs in connection networks. Agents have connection demands in form of pairs of locations they want to have connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection...

  16. Evaluation of software tools for automated identification of neuroanatomical structures in quantitative β-amyloid PET imaging to diagnose Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Tuszynski, Tobias; Luthardt, Julia; Butzke, Daniel; Tiepolt, Solveig; Seese, Anita; Barthel, Henryk [Leipzig University Medical Centre, Department of Nuclear Medicine, Leipzig (Germany); Rullmann, Michael; Hesse, Swen; Sabri, Osama [Leipzig University Medical Centre, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Centre, Integrated Treatment and Research Centre (IFB) Adiposity Diseases, Leipzig (Germany); Gertz, Hermann-Josef [Leipzig University Medical Centre, Department of Psychiatry, Leipzig (Germany); Lobsien, Donald [Leipzig University Medical Centre, Department of Neuroradiology, Leipzig (Germany)

    2016-06-15

    For regional quantification of nuclear brain imaging data, defining volumes of interest (VOIs) by hand is still the gold standard. As this procedure is time-consuming and operator-dependent, a variety of software tools for automated identification of neuroanatomical structures were developed. As the quality and performance of those tools are poorly investigated so far in analyzing amyloid PET data, we compared in this project four algorithms for automated VOI definition (HERMES Brass, two PMOD approaches, and FreeSurfer) against the conventional method. We systematically analyzed florbetaben brain PET and MRI data of ten patients with probable Alzheimer's dementia (AD) and ten age-matched healthy controls (HCs) collected in a previous clinical study. VOIs were manually defined on the data as well as through the four automated workflows. Standardized uptake value ratios (SUVRs) with the cerebellar cortex as a reference region were obtained for each VOI. SUVR comparisons between ADs and HCs were carried out using Mann-Whitney-U tests, and effect sizes (Cohen's d) were calculated. SUVRs of automatically generated VOIs were correlated with SUVRs of conventionally derived VOIs (Pearson's tests). The composite neocortex SUVRs obtained by manually defined VOIs were significantly higher for ADs vs. HCs (p=0.010, d=1.53). This was also the case for the four tested automated approaches which achieved effect sizes of d=1.38 to d=1.62. SUVRs of automatically generated VOIs correlated significantly with those of the hand-drawn VOIs in a number of brain regions, with regional differences in the degree of these correlations. Best overall correlation was observed in the lateral temporal VOI for all tested software tools (r=0.82 to r=0.95, p<0.001). Automated VOI definition by the software tools tested has a great potential to substitute for the current standard procedure to manually define VOIs in β-amyloid PET data analysis. (orig.)

  17. Neuroanatomical localization of nitric oxide synthase (nNOS) in the central nervous system of carp, Labeo rohita during post-embryonic development.

    Science.gov (United States)

    Biswas, Saikat P; Jadhao, Arun G; Bhoyar, Rahul C; Palande, Nikhil V; Sinh, Dharmendra P

    2015-11-01

    Nitric oxide (NO) is a chemically diffusible molecular messenger playing various roles in both vertebrates and invertebrates. Nitric oxide synthase (NOS) is the key enzyme in synthesis of NO. The neuroanatomical distribution pattern of neuronal nitric oxide synthase (nNOS) was studied and developing stages of Labeo rohita such as hatchlings (10-15mm), frys (15-35mm), semi-fingerlings (35-65mm), fingerlings (65-100mm) and adults (350-370mm) were used. In the telencephalon, nitrergic cells were observed in both pallial and subpallial regions along with entopeduncular nucleus suggesting the involvement of NO in the control of sensory functions throughout the development. In the diencephalon, nNOS positive neurons were localized in the nucleus preopticus periventricularis and preopticus parvocellularis throughout development while nucleus preopticus magnocellularis was found immunopositive only in adult specimens who suggest the involvement of NO in the hormonal regulation. nNOS immunoreaction was also noted in suprachaismatic nucleus, habenula, lateral tuberal nucleus, paraventricular organ and anterior division of preglomerular nucleus throughout development. In the mesencephalic region, nNOS immunoreactivity was seen in the optic tectum, torus longitudinalis, nucleus of median longitudinal fascicle and occulomotor nucleus indicate the role of NO in integration of visual inputs and modulates motor control of the eyes and movements. Caudally, in the rhombencephalon, the cerebellum, the nucleus reticularis, the octaval nucleus and the motor nucleus of vagal nerve were nNOS positive during development. nNOS reactive cells and fibers were noted in the spinal motor column, thus suggesting a role of NO in gestation and startle response from early development.

  18. MedlinePlus Connect

    Science.gov (United States)

    ... IT systems, patient portals and electronic health record (EHR) systems to relevant, authoritative patient health information from ... they need it via their patient portal or EHR. How does MedlinePlus Connect work? MedlinePlus Connect responds ...

  19. Galois connections and applications

    CERN Document Server

    Erné, M; Wismath, S

    2004-01-01

    This book presents the main ideas of General Galois Theory as a generalization of Classical Galois Theory It sketches the development of Galois connections through the last three centuries Examples of Galois connections as powerful tools in Category Theory and Universal Algebra are given Applications of Galois connections in Linguistic and Data Analysis are presented

  20. Deficits in episodic memory retrieval reveal impaired default mode network connectivity in amnestic mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Cameron J. Dunn

    2014-01-01

    Full Text Available Amnestic mild cognitive impairment (aMCI is believed to represent a transitional stage between normal healthy ageing and the development of dementia. In particular, aMCI patients have been shown to have higher annual transition rates to Alzheimer's Disease (AD than individuals without cognitive impairment. Despite intensifying interest investigating the neuroanatomical basis of this transition, there remain a number of questions regarding the pathophysiological process underlying aMCI itself. A number of recent studies in aMCI have shown specific impairments in connectivity within the default mode network (DMN, which is a group of regions strongly related to episodic memory capacities. However to date, no study has investigated the integrity of the DMN between patients with aMCI and those with a non-amnestic pattern of MCI (naMCI, who have cognitive impairment, but intact memory storage systems. In this study, we contrasted the DMN connectivity in 24 aMCI and 33 naMCI patients using seed-based resting state fMRI. The two groups showed no statistical difference in their DMN intra-connectivity. However when connectivity was analysed according to performance on measures of episodic memory retrieval, the two groups were separable, with aMCI patients demonstrating impaired functional connectivity between the hippocampal formation and the posterior cingulate cortex. We provide evidence that this lack of connectivity is driven by impaired communication from the posterior cingulate hub and does not simply represent hippocampal atrophy, suggesting that posterior cingulate degeneration is the driving force behind impaired DMN connectivity in aMCI.

  1. 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...

  2. Rescuing Perishable Neuroanatomical Information from a Threatened Biodiversity Hotspot: Remote Field Methods for Brain Tissue Preservation Validated by Cytoarchitectonic Analysis, Immunohistochemistry, and X-Ray Microcomputed Tomography.

    Science.gov (United States)

    Hughes, Daniel F; Walker, Ellen M; Gignac, Paul M; Martinez, Anais; Negishi, Kenichiro; Lieb, Carl S; Greenbaum, Eli; Khan, Arshad M

    2016-01-01

    Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are increasingly threatened. There is a need to accelerate collection efforts in these regions before threatened or endangered species become extinct. The diverse geographical, ecological, genetic, morphological, and behavioral data generated from the on-site collection of an individual specimen are useful for many scientific purposes. However, traditional methods for specimen preparation in the field do not permit researchers to retrieve neuroanatomical data, disregarding potentially useful data for increasing our understanding of brain diversity. These data have helped clarify brain evolution, deciphered relationships between structure and function, and revealed constraints and selective pressures that provide context about the evolution of complex behavior. Here, we report our field-testing of two commonly used laboratory-based techniques for brain preservation while on a collecting expedition in the Congo Basin and Albertine Rift, two poorly known regions associated with the Eastern Afromontane biodiversity hotspot. First, we found that transcardial perfusion fixation and long-term brain storage, conducted in remote field conditions with no access to cold storage laboratory equipment, had no observable impact on cytoarchitectural features of lizard brain tissue when compared to lizard brain tissue processed under laboratory conditions. Second, field-perfused brain tissue subjected to prolonged post-fixation remained readily compatible with subsequent immunohistochemical detection of neural antigens, with immunostaining that was comparable to that of laboratory-perfused brain tissue. Third, immersion-fixation of lizard brains, prepared under identical environmental conditions, was readily compatible with subsequent iodine-enhanced X-ray microcomputed tomography, which facilitated the non-destructive imaging of the intact brain within its skull. In summary, we have validated

  3. Rescuing Perishable Neuroanatomical Information from a Threatened Biodiversity Hotspot: Remote Field Methods for Brain Tissue Preservation Validated by Cytoarchitectonic Analysis, Immunohistochemistry, and X-Ray Microcomputed Tomography

    Science.gov (United States)

    Hughes, Daniel F.; Walker, Ellen M.; Gignac, Paul M.; Martinez, Anais; Negishi, Kenichiro; Lieb, Carl S.; Greenbaum, Eli

    2016-01-01

    Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are increasingly threatened. There is a need to accelerate collection efforts in these regions before threatened or endangered species become extinct. The diverse geographical, ecological, genetic, morphological, and behavioral data generated from the on-site collection of an individual specimen are useful for many scientific purposes. However, traditional methods for specimen preparation in the field do not permit researchers to retrieve neuroanatomical data, disregarding potentially useful data for increasing our understanding of brain diversity. These data have helped clarify brain evolution, deciphered relationships between structure and function, and revealed constraints and selective pressures that provide context about the evolution of complex behavior. Here, we report our field-testing of two commonly used laboratory-based techniques for brain preservation while on a collecting expedition in the Congo Basin and Albertine Rift, two poorly known regions associated with the Eastern Afromontane biodiversity hotspot. First, we found that transcardial perfusion fixation and long-term brain storage, conducted in remote field conditions with no access to cold storage laboratory equipment, had no observable impact on cytoarchitectural features of lizard brain tissue when compared to lizard brain tissue processed under laboratory conditions. Second, field-perfused brain tissue subjected to prolonged post-fixation remained readily compatible with subsequent immunohistochemical detection of neural antigens, with immunostaining that was comparable to that of laboratory-perfused brain tissue. Third, immersion-fixation of lizard brains, prepared under identical environmental conditions, was readily compatible with subsequent iodine-enhanced X-ray microcomputed tomography, which facilitated the non-destructive imaging of the intact brain within its skull. In summary, we have validated

  4. Rescuing Perishable Neuroanatomical Information from a Threatened Biodiversity Hotspot: Remote Field Methods for Brain Tissue Preservation Validated by Cytoarchitectonic Analysis, Immunohistochemistry, and X-Ray Microcomputed Tomography.

    Directory of Open Access Journals (Sweden)

    Daniel F Hughes

    Full Text Available Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are increasingly threatened. There is a need to accelerate collection efforts in these regions before threatened or endangered species become extinct. The diverse geographical, ecological, genetic, morphological, and behavioral data generated from the on-site collection of an individual specimen are useful for many scientific purposes. However, traditional methods for specimen preparation in the field do not permit researchers to retrieve neuroanatomical data, disregarding potentially useful data for increasing our understanding of brain diversity. These data have helped clarify brain evolution, deciphered relationships between structure and function, and revealed constraints and selective pressures that provide context about the evolution of complex behavior. Here, we report our field-testing of two commonly used laboratory-based techniques for brain preservation while on a collecting expedition in the Congo Basin and Albertine Rift, two poorly known regions associated with the Eastern Afromontane biodiversity hotspot. First, we found that transcardial perfusion fixation and long-term brain storage, conducted in remote field conditions with no access to cold storage laboratory equipment, had no observable impact on cytoarchitectural features of lizard brain tissue when compared to lizard brain tissue processed under laboratory conditions. Second, field-perfused brain tissue subjected to prolonged post-fixation remained readily compatible with subsequent immunohistochemical detection of neural antigens, with immunostaining that was comparable to that of laboratory-perfused brain tissue. Third, immersion-fixation of lizard brains, prepared under identical environmental conditions, was readily compatible with subsequent iodine-enhanced X-ray microcomputed tomography, which facilitated the non-destructive imaging of the intact brain within its skull. In summary, we

  5. Relating anatomical and social connectivity: white matter microstructure predicts emotional empathy.

    Science.gov (United States)

    Parkinson, Carolyn; Wheatley, Thalia

    2014-03-01

    Understanding cues to the internal states of others involves a widely distributed network of brain regions. Although white matter (WM) connections are likely crucial for communication between these regions, the role of anatomical connectivity in empathic processing remains unexplored. The present study tested for a relationship between anatomical connectivity and empathy by assessing the WM microstructural correlates of affective empathy, which promotes interpersonal understanding through emotional reactions, and cognitive empathy, which does so via perspective taking. Associations between fractional anisotropy (FA) and the emotional (empathic concern, EC) and cognitive (perspective taking, PT) dimensions of empathy as assessed by the Interpersonal Reactivity Index were examined. EC was positively associated with FA in tracts providing communicative pathways within the limbic system, between perception and action-related regions, and between perception and affect-related regions, independently of individual differences in age, gender, and other dimensions of interpersonal reactivity. These findings provide a neuroanatomical basis for the rapid, privileged processing of emotional sensory information and the automatic elicitation of responses to the affective displays of others. PMID:23162046

  6. Relating anatomical and social connectivity: white matter microstructure predicts emotional empathy.

    Science.gov (United States)

    Parkinson, Carolyn; Wheatley, Thalia

    2014-03-01

    Understanding cues to the internal states of others involves a widely distributed network of brain regions. Although white matter (WM) connections are likely crucial for communication between these regions, the role of anatomical connectivity in empathic processing remains unexplored. The present study tested for a relationship between anatomical connectivity and empathy by assessing the WM microstructural correlates of affective empathy, which promotes interpersonal understanding through emotional reactions, and cognitive empathy, which does so via perspective taking. Associations between fractional anisotropy (FA) and the emotional (empathic concern, EC) and cognitive (perspective taking, PT) dimensions of empathy as assessed by the Interpersonal Reactivity Index were examined. EC was positively associated with FA in tracts providing communicative pathways within the limbic system, between perception and action-related regions, and between perception and affect-related regions, independently of individual differences in age, gender, and other dimensions of interpersonal reactivity. These findings provide a neuroanatomical basis for the rapid, privileged processing of emotional sensory information and the automatic elicitation of responses to the affective displays of others.

  7. 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

  8. 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.

  9. 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).

  10. 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…

  11. Generalised Connections and Curvature

    OpenAIRE

    Kunzinger, Michael; Steinbauer, Roland; Vickers, James A.

    2004-01-01

    The concept of generalised (in the sense of Colombeau) connection on a principal fibre bundle is introduced. This definition is then used to extend results concerning the geometry of principal fibre bundles to those that only have a generalised connection. Some applications to singular solutions of Yang-Mills theory are given.

  12. 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.

  13. 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...

  14. Knowledge engineering tools for reasoning with scientific observations and interpretations: a neural connectivity use case

    Directory of Open Access Journals (Sweden)

    Bota Mihail

    2011-08-01

    Full Text Available Abstract Background We address the goal of curating observations from published experiments in a generalizable form; reasoning over these observations to generate interpretations and then querying this interpreted knowledge to supply the supporting evidence. We present web-application software as part of the 'BioScholar' project (R01-GM083871 that fully instantiates this process for a well-defined domain: using tract-tracing experiments to study the neural connectivity of the rat brain. Results The main contribution of this work is to provide the first instantiation of a knowledge representation for experimental observations called 'Knowledge Engineering from Experimental Design' (KEfED based on experimental variables and their interdependencies. The software has three parts: (a the KEfED model editor - a design editor for creating KEfED models by drawing a flow diagram of an experimental protocol; (b the KEfED data interface - a spreadsheet-like tool that permits users to enter experimental data pertaining to a specific model; (c a 'neural connection matrix' interface that presents neural connectivity as a table of ordinal connection strengths representing the interpretations of tract-tracing data. This tool also allows the user to view experimental evidence pertaining to a specific connection. BioScholar is built in Flex 3.5. It uses Persevere (a noSQL database as a flexible data store and PowerLoom® (a mature First Order Logic reasoning system to execute queries using spatial reasoning over the BAMS neuroanatomical ontology. Conclusions We first introduce the KEfED approach as a general approach and describe its possible role as a way of introducing structured reasoning into models of argumentation within new models of scientific publication. We then describe the design and implementation of our example application: the BioScholar software. This is presented as a possible biocuration interface and supplementary reasoning toolkit for a larger

  15. 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 ${\\bf E} \\cdot {\\bf B} = 0$.

  16. Covariant magnetic connection hypersurfaces

    Science.gov (United States)

    Pegoraro, F.

    2016-04-01

    > In the single fluid, non-relativistic, 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 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 .

  17. Can we measure connectivity?

    Science.gov (United States)

    Brazier, Richard; Vericat, Damia; Cerda, Artemi; Brardinoni, Francesco; Batalla, Ramon; Masselink, Rens; Wittenberg, Lea; Nadal Romero, Estela; López-Tarazón, José; Estrany, Joan; Keesstra, Saskia

    2015-04-01

    Whilst the term 'connectivity' in hydrological and sediment-based research is becoming increasing well-known, it is neither used consistently in the existing literature, nor is it clear from that literature, that the connectivity of a landscape, or part of a landscape can be measured. However, it is argued that understanding how well critical source areas of water or sediment are connected to receiving surface waters, may be an essential step towards improvement of land management to mitigate flooding, soil erosion and water quality problems. The first part of this paper, therefore, explores what is currently meant by the term connectivity; addressing the differences between structural and functional, or process-based connectivity, specifically with reference to the movement of water and sediment through an ecosystem. We argue that most existing studies do not measure connectivity. Instead, they address only part of the story. Existing work may describe structural change in a landscape, which can perhaps elucidate the potential for connectivity to occur, or indeed the emergent spatial properties of an ecosystem, but it rarely quantifies the connectivity of an ecosystem in a process-based manner through time. Alternatively, a great deal of work describes fluxes of water and sediment at (sometimes multiple) points in a landscape and infers connectivity of the system via analysis of time series data; from rainfall peak to hydrograph peak or start of sediment flux until peak sediment flux within an event. Such data are doubtless useful to understand catchment function, but alone, they do not provide evidence that quantifies (for example) how well connected sediment sources are to the outlets of the catchments from which they flux. Finally, there are many examples of water and particularly sediment tracing studies, which attempt to link, either directly or indirectly water or sediment sources with their sinks (which might more usefully be termed temporary stores

  18. HIV-AIDS Connection

    Science.gov (United States)

    ... Content Marketing Share this: Main Content Area The HIV-AIDS Connection AIDS was first recognized in 1981 ... cancers. Why is there overwhelming scientific consensus that HIV causes AIDS? Before HIV infection became widespread in ...

  19. Green Connections Network

    Data.gov (United States)

    City of San Francisco — Green Connections aims to increase access to parks, open spaces, and the waterfront by envisioning a network of ���green connectors�۪ ��� city streets that will be...

  20. 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,

  1. Series connection of IGBT

    OpenAIRE

    Nguyen, The Van; Jeannin, Pierre-Olivier; Vagnon, Eric; Frey, David; Crébier, Jean-Christophe

    2010-01-01

    International audience This article analyzes the effects of parasitic capacitances in the series connection of IGBT, which exist naturally due to gate driver and power circuit geometry. Two solutions, that can be combined, are proposed to minimize these effects in order to achieve a better voltage balancing. The first one is based on gate driver self-powering technique. The second one is based on a vertical structure assembly of IGBT connected in series. The performance offered by these tw...

  2. Quick connect fastener

    Science.gov (United States)

    Weddendorf, Bruce (Inventor)

    1994-01-01

    A quick connect fastener and method of use is presented wherein the quick connect fastener is suitable for replacing available bolts and screws, the quick connect fastener being capable of installation by simply pushing a threaded portion of the connector into a member receptacle hole, the inventive apparatus being comprised of an externally threaded fastener having a threaded portion slidably mounted upon a stud or bolt shaft, wherein the externally threaded fastener portion is expandable by a preloaded spring member. The fastener, upon contact with the member receptacle hole, has the capacity of presenting cylindrical threads of a reduced diameter for insertion purposes and once inserted into the receiving threads of the receptacle member hole, are expandable for engagement of the receptacle hole threads forming a quick connect of the fastener and the member to be fastened, the quick connect fastener can be further secured by rotation after insertion, even to the point of locking engagement, the quick connect fastener being disengagable only by reverse rotation of the mated thread engagement.

  3. Connectivity and neurochemistry of the commissura anterior of the pigeon (Columba livia).

    Science.gov (United States)

    Letzner, Sara; Simon, Annika; Güntürkün, Onur

    2016-02-01

    The anterior commissure (AC) and the much smaller hippocampal commissure constitute the only interhemispheric pathways at the telencephalic level in birds. Since the degeneration study from Zeier and Karten (), no detailed description of the topographic organization of the AC has been performed. This information is not only necessary for a better understanding of interhemispheric transfer in birds, but also for a comparative analysis of the evolution of commissural systems in the vertebrate classes. We therefore examined the fiber connections of the AC by using choleratoxin subunit B (CTB) and biotinylated dextran amine (BDA). Injections into subareas of the arcopallium and posterior amygdala (PoA) demonstrated contralateral projection fields within the anterior arcopallium (AA), intermediate arcopallium (AI), PoA, lateral, caudolateral and central nidopallium, dorsal and ventral mesopallium, and medial striatum (MSt). Interestingly, only arcopallial and amygdaloid projections were reciprocally organized, and all AC projections originated within a rather small area of the arcopallium and the PoA. The commissural neurons were not GABA-positive, and thus possibly not of an inhibitory nature. In sum, our neuroanatomical study demonstrates that a small group of arcopallial and amygdaloid neurons constitute a wide range of contralateral projections to sensorimotor and limbic structures. Different from mammals, in birds the neurons that project via the AC constitute mostly heterotopically organized and unidirectional connections. In addition, the great majority of pallial areas do not participate by themselves in interhemispheric exchange in birds. Instead, commissural exchange rests on a rather small arcopallial and amygdaloid cluster of neurons. PMID:26179777

  4. Connectivity and neurochemistry of the commissura anterior of the pigeon (Columba livia).

    Science.gov (United States)

    Letzner, Sara; Simon, Annika; Güntürkün, Onur

    2016-02-01

    The anterior commissure (AC) and the much smaller hippocampal commissure constitute the only interhemispheric pathways at the telencephalic level in birds. Since the degeneration study from Zeier and Karten (), no detailed description of the topographic organization of the AC has been performed. This information is not only necessary for a better understanding of interhemispheric transfer in birds, but also for a comparative analysis of the evolution of commissural systems in the vertebrate classes. We therefore examined the fiber connections of the AC by using choleratoxin subunit B (CTB) and biotinylated dextran amine (BDA). Injections into subareas of the arcopallium and posterior amygdala (PoA) demonstrated contralateral projection fields within the anterior arcopallium (AA), intermediate arcopallium (AI), PoA, lateral, caudolateral and central nidopallium, dorsal and ventral mesopallium, and medial striatum (MSt). Interestingly, only arcopallial and amygdaloid projections were reciprocally organized, and all AC projections originated within a rather small area of the arcopallium and the PoA. The commissural neurons were not GABA-positive, and thus possibly not of an inhibitory nature. In sum, our neuroanatomical study demonstrates that a small group of arcopallial and amygdaloid neurons constitute a wide range of contralateral projections to sensorimotor and limbic structures. Different from mammals, in birds the neurons that project via the AC constitute mostly heterotopically organized and unidirectional connections. In addition, the great majority of pallial areas do not participate by themselves in interhemispheric exchange in birds. Instead, commissural exchange rests on a rather small arcopallial and amygdaloid cluster of neurons.

  5. Enhanced Synaptic Connectivity in the Dentate Gyrus during Epileptiform Activity: Network Simulation

    Directory of Open Access Journals (Sweden)

    Keite Lira de Almeida França

    2013-01-01

    Full Text Available Structural rearrangement of the dentate gyrus has been described as the underlying cause of many types of epilepsies, particularly temporal lobe epilepsy. It is said to occur when aberrant connections are established in the damaged hippocampus, as described in human epilepsy and experimental models. Computer modelling of the dentate gyrus circuitry and the corresponding structural changes has been used to understand how abnormal mossy fibre sprouting can subserve seizure generation observed in experimental models when epileptogenesis is induced by status epilepticus. The model follows the McCulloch-Pitts formalism including the representation of the nonsynaptic mechanisms. The neuronal network comprised granule cells, mossy cells, and interneurons. The compensation theory and the Hebbian and anti-Hebbian rules were used to describe the structural rearrangement including the effects of the nonsynaptic mechanisms on the neuronal activity. The simulations were based on neuroanatomic data and on the connectivity pattern between the cells represented. The results suggest that there is a joint action of the compensation theory and Hebbian rules during the inflammatory process that accompanies the status epilepticus. The structural rearrangement simulated for the dentate gyrus circuitry promotes speculation about the formation of the abnormal mossy fiber sprouting and its role in epileptic seizures.

  6. Strengthening connections: functional connectivity and brain plasticity

    OpenAIRE

    Kelly, Clare; Castellanos, F. Xavier

    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...

  7. 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.

  8. 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

  9. VANET Connectivity Analysis

    CERN Document Server

    Kafsi, M; Dousse, O; Alpcan, T; Hubaux, J -P

    2009-01-01

    Vehicular Ad Hoc Networks (VANETs) are a peculiar subclass of mobile ad hoc networks that raise a number of technical challenges, notably from the point of view of their mobility models. In this paper, we provide a thorough analysis of the connectivity of such networks by leveraging on well-known results of percolation theory. By means of simulations, we study the influence of a number of parameters, including vehicle density, proportion of equipped vehicles, and radio communication range. We also study the influence of traffic lights and roadside units. Our results provide insights on the behavior of connectivity. We believe this paper to be a valuable framework to assess the feasibility and performance of future applications relying on vehicular connectivity in urban scenarios.

  10. 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.

  11. Canceled connections: Lesion-derived network mapping helps explain differences in performance on a complex decision-making task.

    Science.gov (United States)

    Sutterer, Matthew J; Bruss, Joel; Boes, Aaron D; Voss, Michelle W; Bechara, Antoine; Tranel, Daniel

    2016-05-01

    Studies of patients with brain damage have highlighted a broad neural network of limbic and prefrontal areas as important for adaptive decision-making. However, some patients with damage outside these regions have impaired decision-making behavior, and the behavioral impairments observed in these cases are often attributed to the general variability in behavior following brain damage, rather than a deficit in a specific brain-behavior relationship. A novel approach, lesion-derived network mapping, uses healthy subject resting-state functional connectivity (RSFC) data to infer the areas that would be connected with each patient's lesion area in healthy adults. Here, we used this approach to investigate whether there was a systematic pattern of connectivity associated with decision-making performance in patients with focal damage in areas not classically associated with decision-making. These patients were categorized a priori into "impaired" or "unimpaired" groups based on their performance on the Iowa Gambling Task (IGT). Lesion-derived network maps based on the impaired patients showed overlap in somatosensory, motor and insula cortices, to a greater extent than patients who showed unimpaired IGT performance. Akin to the classic concept of "diaschisis" (von Monakow, 1914), this focus on the remote effects that focal damage can have on large-scale distributed brain networks has the potential to inform not only differences in decision-making behavior, but also other cognitive functions or neurological syndromes where a distinct phenotype has eluded neuroanatomical classification and brain-behavior relationships appear highly heterogeneous. PMID:26994344

  12. Cortical connectivity suggests a role in limb coordination for macaque area PE of the superior parietal cortex.

    Science.gov (United States)

    Bakola, Sophia; Passarelli, Lauretta; Gamberini, Michela; Fattori, Patrizia; Galletti, Claudio

    2013-04-10

    In macaques, superior parietal lobule area 5 has been described as occupying an extensive region, which includes the caudal half of the postcentral convexity as well as the medial bank of the intraparietal sulcus. Modern neuroanatomical methods have allowed the identification of various areas within this region. In the present study, we investigated the corticocortical afferent projections of one of these subdivisions, area PE. Our results demonstrate that PE, defined as a single architectonic area that contains a topographic map of the body, forms specific connections with somatic and motor fields. Thus, PE receives major afferents from parietal areas, mainly area 2, PEc, several areas in the medial bank of the intraparietal sulcus, opercular areas PGop/PFop, and the retroinsular area, frontal afferents from the primary motor cortex, the supplementary motor area, and the caudal subdivision of dorsal premotor cortex, as well as afferents from cingulate areas PEci, 23, and 24. The presence and relative strength of these connections depend on the location of injection sites, so that lateral PE receives preferential input from anterior sectors of the medial bank of intraparietal sulcus and from the ventral premotor cortex, whereas medial PE forms denser connections with area PEc and motor fields. In contrast with other posterior parietal areas, there are no projections to PE from occipital or prefrontal cortices. Overall, the sensory and motor afferents to PE are consistent with functions in goal-directed movement but also hint at a wider variety of motor coordination roles. PMID:23575861

  13. The Connectivity Order of Links

    CERN Document Server

    Dugowson, Stéphane

    2008-01-01

    We associate at each link a connectivity space which describes its splittability properties. Then, the notion of order for finite connectivity spaces results in the definition of a new numerical invariant for links, their connectivity order. A section of this short paper presents a theorem which asserts that every finite connectivity structure can be realized by a link : the Brunn-Debrunner-Kanenobu Theorem.

  14. 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.

  15. 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

  16. Connecting to Compete 2016

    OpenAIRE

    Arvis, Jean-François; Saslavsky, Daniel; Ojala, Lauri; Shepherd, Ben; Busch, Christina; Raj, Anasuya; Naula, Tapio

    2016-01-01

    The LPI has provided valuable information for policy makers, traders, and other stakeholders, including researchers and academics, on the role of logistics for growth and the policies needed to support logistics in areas such as infrastructure planning, service provision, and crossborder trade and transport facilitation. The results of Connecting to Compete 2016 point to Germany as the bes...

  17. From connection to customer

    International Nuclear Information System (INIS)

    Energy companies can no longer be certain that a customer today will remain a customer tomorrow. They have to work hard to achieve that. They are going from thinking in terms of connections to pampering their customers. Good Customer Relationship Management is a way to achieve a competitive advantage. The whole organisation has to adapt, particularly the customer orientation of employees

  18. 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

  19. High Quality Connections

    OpenAIRE

    Balslev, Lise; Molin, Jan

    2014-01-01

    Gode og stærke relationer er afgørende for en organisations livskraft. Motivation, engagement, effektivitet, kreativitet mv. er nemlig ofte direkte forbundet med organisationens evne til at skabe stærke relationer mellem ledere, medarbejdere, kunder og omverden. Jane Dutton, Professor of Business Administration and Psychology ved Michigan University, introducerer begrebet High Quality Connections (HQC) og siger.

  20. 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…

  1. 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…

  2. Clip, Connect, Clone

    DEFF Research Database (Denmark)

    Fujima, Jun; Lunzer, Aran; Hornbæk, Kasper Anders Søren;

    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. Covert connection of filaments

    CERN Document Server

    Filippov, Boris

    2015-01-01

    We analyse the relationship between two near filaments, which do not show any connection in H-alpha images but reveal close magnetic connectivity during filament activations in Extreme Ultraviolet (EUV) observations. A twisted flux rope, which connects a half of one filament with another filament, becomes visible during several activations but seems to exist all the time of the filaments presence on the disc. Solar Dynamic Observatory} (SDO) and Solar Terrestrial Relations Observatory (STEREO) observed the region with the filaments from two points of view separated by the angle of about 120 deg. On 2012 July 27, SDO observed the filament activation on disc, while for the STEREO B position the filaments were visible at the limb. Nearly identical interaction episode was observed on 2012 August 04 by STEREO A on disc and by SDO at the limb. This good opportunity allows us to disentangle the 3-D shape of the connecting flux rope and in particular to determine with high reliability the helicity sign of the flux ro...

  4. 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.

  5. 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.

  6. Skeletal muscle connective tissue

    DEFF Research Database (Denmark)

    Brüggemann, Dagmar Adeline

    to accumulation of intermolecular cross-links are thought to be the cause, though no cross-link could be identified, that could confirm this hypothesis. Yet, although it has never been possible to demonstrate a direct relation between the total amount of collagen and tenderness, it is still generally agreed...... composition, the organizational structure of connective tissue, the role of connective tissue in muscle contraction and the generation of force, metabolic regulation of arterial structure focusing on associated collagen changes, and a new highly-specific technique for following in three-dimensions changes...... systems of muscle have been visualized in their full complexity, including the ‘neglected' lymphatic capillaries at the level of the endomysium. These findings serve to remind us that muscle contraction is not only about force generation and transmission, but also about nutrient supply and waste removal...

  7. Finding significantly connected voxels based on histograms of connection strengths

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Pedersen, Morten; Darkner, Sune

    2016-01-01

    We explore a new approach for structural connectivity based segmentations of subcortical brain regions. Connectivity based segmentations are usually based on fibre connections from a seed region to predefined target regions. We present a method for finding significantly connected voxels based...... on the distribution of connection strengths. Paths from seed voxels to all voxels in a target region are obtained from a shortest-path tractography. For each seed voxel we approximate the distribution with a histogram of path scores. We hypothesise that the majority of estimated connections are false......-positives and that their connection strength is distributed differently from true-positive connections. Therefore, an empirical null-distribution is defined for each target region as the average normalized histogram over all voxels in the seed region. Single histograms are then tested against the corresponding null...

  8. Empowering Human Connected Communities

    OpenAIRE

    Cerri, Stefano A.

    2012-01-01

    International audience The keynote's goal is to reflect on emergent opportunities for human Discovery (in science), Creativity (in art & industry), and Learning (in education) as processes often occurring serendipitously in individuals and in communities empowered by dynamic Web connections in the global village. These reflections seem to fit best with the mandate of the CBIE Conference: sustainable education. Having been influenced by the pioneering work of the late ecologist Francesco Di...

  9. Mobile connections : curator's statement.

    OpenAIRE

    Hemment, Drew

    2004-01-01

    The Mobile Connections exhibition at the Futuresonic 2004 festival explored how mobile and locative media reconfigure social, cultural and information space. It looked beyond computing in its current form, towards the social and cultural possibilities opened by a new generation of networked, location-aware media. It sought an art of mobile communications: asking, are there any forms of expression that are intrinsic or unique to mobile and locative media?

  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. Back to front: cerebellar connections and interactions with the prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Thomas C Watson

    2014-02-01

    Full Text Available Although recent neuroanatomical evidence has demonstrated closed-loop connectivity between prefrontal cortex and the cerebellum, the physiology of cerebello-cerebral circuits and the extent to which cerebellar output modulates neuronal activity in neocortex during behavior remain relatively unexplored. We show that electrical stimulation of the contralateral cerebellar fastigial nucleus (FN in awake, behaving rats evokes distinct local field potential (LFP responses (onset latency ~13 ms in the prelimbic (PrL subdivision of the medial prefrontal cortex. Trains of FN stimulation evoke heterogeneous patterns of response in putative pyramidal cells in frontal and prefrontal regions in both urethane-anaesthetized and awake, behaving rats. However, the majority of cells showed decreased firing rates during stimulation and subsequent rebound increases; more than 90% of cells showed significant changes in response. Simultaneous recording of on-going LFP activity from FN and PrL while rats were at rest or actively exploring an open field arena revealed significant network coherence restricted to the theta frequency range (5-10 Hz. Granger causality analysis indicated that this coherence was significantly directed from cerebellum to PrL during active locomotion. Our results demonstrate the presence of a cerebello-prefrontal pathway in rat and reveal behaviorally dependent coordinated network activity between the two structures, which could facilitate transfer of sensorimotor information into ongoing neocortical processing during goal directed behaviors.

  13. Bi-connected Gravity Fields

    CERN Document Server

    Bel, Lluís

    2016-01-01

    I describe a bi-connection formalism of General relativity based on the dual role of the Weitzenb\\"{o}ck connection defining the parallelism at a distance and the concomitant Levi-Civita connection derived from the Riemannian metric. A more explicit tensor writing of the geodesic and loxodromic equations clarifies their joint meaning.

  14. Positive fast sealing union connections

    Science.gov (United States)

    Kleber, C. M.

    1972-01-01

    Union connections are designed for connecting high pressure flexible hoses from gas storage manifolds to gas transport trailers. Connection uses O ring seals which can be quickly assembled and disassembled without use of wrenches, and which do not twist hose. Worn or damaged O rings are easily replaced.

  15. Attribute-space connected filters

    NARCIS (Netherlands)

    Wilkinson, Michael H.F.; Ronse, C; Najman, L; Decenciere, E

    2005-01-01

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

  16. Connecting to Everyday Practices

    DEFF Research Database (Denmark)

    Iversen, Ole Sejer; Smith, Rachel Charlotte

    2012-01-01

    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...... 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...... focusing on the connections between audiences practices and the museum exhibition....

  17. The Berry's connection

    International Nuclear Information System (INIS)

    A course on the Berry's connection is presented. The main steps leading to the Berry's discovery are reviewed and the obtained equations are examined. Some applications of Berry's formulation are presented. They include diatomic molecules, dipole-quadrupole interaction in spherical mucleus and diabolic pair transfer. The experimental results presented are the spectrum of the Na3 molecule, the propagation of photons in an helical optical fiber and the neutron spin rotation. Non-abelian problems and the Aharonow-Anandan phase are discussed

  18. 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.

  19. Piston and connecting rod assembly

    Science.gov (United States)

    Brogdon, James William (Inventor); Gill, David Keith (Inventor); Chatten, John K. (Inventor)

    2001-01-01

    A piston and connecting rod assembly includes a piston crown, a piston skirt, a connecting rod, and a bearing insert. The piston skirt is a component separate from the piston crown and is connected to the piston crown to provide a piston body. The bearing insert is a component separate from the piston crown and the piston skirt and is fixedly disposed within the piston body. A bearing surface of a connecting rod contacts the bearing insert to thereby movably associate the connecting rod and the piston body.

  20. 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...

  1. 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......&OP process itself is a fluid object, but there is still possibility to organise the messy Production. There are connections between the Production multiple and the managerial technology fluid. The fluid enacted the multiplicity of Production thus making it more difficult to be organised because there were...... always Other representations that enact new relations between presences, manifest absences and others. The multiple was organised in the sense that its mutually exclusive realities were managed by different constituents of the fluid located in these diverse realities. Accounting incompleteness...

  2. 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.

  3. 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.

  4. As bases neuroanatômicas do comportamento: histórico e contribuições recentes Neuroanatomical basis of behavior: history and recent contributions

    Directory of Open Access Journals (Sweden)

    Guilherme Carvalhal Ribas

    2007-03-01

    conjunto com o núcleo basal de Meynert e com o sistema septo-banda diagonal, constituem as principais estruturas e sistemas que possuem conexões com as áreas corticais límbicas e que, em conjunto com estas, atuam sobre o hipotálamo e o tronco encefálico que, por sua vez, geram os componentes autonômicos, endócrinos e somatomotores das experiências emocionais e que regulam as atividades básicas de beber, comer e pertinentes ao comportamento sexual.Considering the most recent contributions, the limbic cortical areas, originally known as the greater limbic lobe, besides the cingulated and the parahippocampal gyri also includes the insula and the posterior orbital cortex. In contrast to the nonlimbic cortical areas that project to the basal ganglia (particularly over the dorsal aspects of the striatum, constituted by the caudate nucleus and by the putamen, the limbic cortical areas are characterized by projecting to the hypothalamus and also to the ventral striatum (particularly to the nucleus accumbens. Once all the striatum projects to the globus pallidus which projects to the thalamus and then to the cortex, generating cortical-subcortical reentrant circuits, while the dorsal striatum and pallidum related cortico-subcortical loops are involved with motor activities, the ventral cortical-striatal-pallidal system is particularly related with behavior functions. The extended amygdala (central medial amygdala, stria terminalis or dorsal component, ventral component, and bed nucleus of stria terminalis receives inputs primarily from the limbic cortical areas, is particularly modulated by the prefrontal cortex, and receives also direct connections from the thalamus that enables the amygdala to generate nonspecific and quick responses through its projections to the hypothalamus and to the brainstem. The ventral striatal-pallidal and the extended amygdala are then two basal forebrain macro-anatomical systems, that together with the basal nucleus of Meynert and with the

  5. 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...

  6. Ideal Systems and Connecting Orbits

    Institute of Scientific and Technical Information of China (English)

    Shu-xiang Yu; Zuo-huan Zheng; Fan-nu Hu

    2004-01-01

    In this paper,we study a class of dynamical systems in R nideal systems and give an existence criterion of quasi-connecting orbits for such systems.Also,an existence criterion of connecting orbits for general systems is given.

  7. [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.

  8. 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...

  9. The Always-Connected Generation

    Science.gov (United States)

    Bull, Glen

    2010-01-01

    The Pew Internet and American Life project characterizes the millennials--the first generation to come of age in the new millennium--as the first "always-connected" generation. Significant aspects of culture are changing as a result. A changing world where all students are connected all the time has substantial educational implications. Despite…

  10. Algebraic Connectivity of Interdependent Networks

    NARCIS (Netherlands)

    Martin-Hernandez, J.; Wang, H.; Van Mieghem, P.; D'Agostino, G.

    2014-01-01

    The algebraic connectivity UN-1, i.e. the second smallest eigenvalue of the Laplacian matrix, plays a crucial role in dynamic phenomena such as diffusion processes, synchronization stability, and network robustness. In this work we study the algebraic connectivity in the general context of interdepe

  11. 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.

  12. Fast whole-brain optical tomography capable of automated slice-collection (Conference Presentation)

    Science.gov (United States)

    Yuan, Jing; Jiang, Tao; Deng, Lei; Long, Beng; Peng, Jie; Luo, Qingming; Gong, Hui

    2016-03-01

    Acquiring brain-wide composite information of neuroanatomical and molecular phenotyping is crucial to understand brain functions. However, current whole-brain imaging methods based on mechnical sectioning haven't achieved brain-wide acquisition of both neuroanatomical and molecular phenotyping due to the lack of appropriate whole-brain immunostaining of embedded samples. Here, we present a novel strategy of acquiring brain-wide structural and molecular maps in the same brain, combining whole-brain imaging and subsequent immunostaining of automated-collected slices. We developed a whole-brain imaging system capable of automatically imaging and then collecting imaged tissue slices in order. The system contains three parts: structured illumination microscopy for high-throughput optical sectioning, vibratome for high-precision sectioning and slice-collection device for automated collecting of tissue slices. Through our system, we could acquire a whole-brain dataset of agarose-embedded mouse brain at lateral resolution of 0.33 µm with z-interval sampling of 100 µm in 9 h, and automatically collect the imaged slices in sequence. Subsequently, we performed immunohistochemistry of the collected slices in the routine way. We acquired mouse whole-brain imaging datasets of multiple specific types of neurons, proteins and gene expression profiles. We believe our method could accelerate systematic analysis of brain anatomical structure with specific proteins or genes expression information and understanding how the brain processes information and generates behavior.

  13. 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...

  14. 33 CFR 156.130 - Connection.

    Science.gov (United States)

    2010-07-01

    ... operations unless it is: (1) A bolted or full threaded connection; or (2) A quick-connect coupling acceptable... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Connection. 156.130 Section 156....130 Connection. (a) Each person who makes a connection for transfer operations shall: (1) Use...

  15. 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.

  16. Cybersecurity for Connected Diabetes Devices.

    Science.gov (United States)

    Klonoff, David C

    2015-09-01

    Diabetes devices are increasingly connected wirelessly to each other and to data-displaying reader devices. Threats to the accurate flow of information and commands may compromise the function of these devices and put their users at risk of health complications. Sound cybersecurity of connected diabetes devices is necessary to maintain confidentiality, integrity, and availability of the data and commands. Diabetes devices can be hacked by unauthorized agents and also by patients themselves to extract data that are not automatically provided by product software. Unauthorized access to connected diabetes devices has been simulated and could happen in reality. A cybersecurity standard designed specifically for connected diabetes devices will improve the safety of these products and increase confidence of users that the products will be secure. PMID:25883162

  17. Cybersecurity for Connected Diabetes Devices

    OpenAIRE

    Klonoff, David C.

    2015-01-01

    Diabetes devices are increasingly connected wirelessly to each other and to data-displaying reader devices. Threats to the accurate flow of information and commands may compromise the function of these devices and put their users at risk of health complications. Sound cybersecurity of connected diabetes devices is necessary to maintain confidentiality, integrity, and availability of the data and commands. Diabetes devices can be hacked by unauthorized agents and also by patients themselves to...

  18. Connected Correlators in Quantum Gravity

    OpenAIRE

    Ambjorn, J.; Bialas, P.; Jurkiewicz, J.(Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, ul. prof. Stanislawa Lojasiewicza 11, Krakow, PL 30-348, Poland)

    1998-01-01

    We discuss the concept of connected, reparameterization invariant matter correlators in quantum gravity. We analyze the effect of discretization in two solvable cases: branched polymers and two-dimensional simplicial gravity. In both cases the naively defined connected correlators for a fixed volume display an anomalous behavior, which could be interpreted as a long-range order. We suggest that this is in fact only a highly non-trivial finite-size effect and propose an improved definition of ...

  19. Connected searching of weighted trees

    CERN Document Server

    Dereniowski, Dariusz

    2010-01-01

    In this paper we consider the problem of connected edge searching of weighted trees. It is shown that there exists a polynomial-time algorithm for finding optimal connected search strategy for bounded degree trees with arbitrary weights on the edges and vertices of the tree. The problem is NP-complete for general node-weighted trees (the weight of each edge is 1).

  20. Pleura: In connective tissue diseases

    OpenAIRE

    Kaushik Saha

    2016-01-01

    Connective tissue diseases (CTDs) (or collagen vascular diseases) represent a heterogeneous group of immunologically mediated disorders that affects many organs of the body including pleura. Frequency, presentation, and prognosis of pleural involvement depend on the underlying CTD. Connective tissue disorders may be heritable such as Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta; and autoimmune such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), syste...

  1. Neuroanatomical automatic segmentation in brain cancer patients

    OpenAIRE

    D’Haese, P.; Niermann, K; Cmelak, A.; Donnelly, E.; Duay, V.; Li, R; Dawant, B.

    2003-01-01

    Conformally prescribed radiation therapy for brain cancer requires precisely defining the target treatment area, as well as delineating vital brain structures which must be spared from radiotoxicity. The current clinical practice of manually segmenting brain structures can be complex and exceedingly time consuming. Automatic computeraided segmentation methods have been proposed to increase efficiency and reproducibility in developing radiation treatment plans. Previous studies have establishe...

  2. Serotonin & Ejaculation : a psychopharmacological and neuroanatomical approach

    OpenAIRE

    de Jong, T.R.

    2005-01-01

    Ejaculatory dysfunctions, such as premature or retarded ejaculation, are common human disorders that can be very stressful for patients and their partners. In recent years it became clear that ejaculatory disorders have a neurobiological rather than a psychological cause, indicating that psychopharmacological drugs might be able to treat abnormal ejaculations. In the present thesis the neurobiology of ejaculation was investigated, to gain knowledge that can be used in the development of such ...

  3. Review on Cold-Formed Steel Connections

    Directory of Open Access Journals (Sweden)

    Yeong Huei Lee

    2014-01-01

    Full Text Available The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed.

  4. Review on cold-formed steel connections.

    Science.gov (United States)

    Lee, Yeong Huei; Tan, Cher Siang; Mohammad, Shahrin; Tahir, Mahmood Md; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  5. Intermodal Passenger Connectivity Database - Raw Data

    Data.gov (United States)

    Department of Transportation — The Intermodal Passenger Connectivity Database (IPCD) is a nationwide data table of passenger transportation terminals, with data on the availability of connections...

  6. Review on Cold-Formed Steel Connections

    Science.gov (United States)

    Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

  7. 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.

  8. Continuously Connected With Mobile IP

    Science.gov (United States)

    2002-01-01

    Cisco Systems developed Cisco Mobile Networks, making IP devices mobile. With this innovation, a Cisco router and its connected IP devices can roam across network boundaries and connection types. Because a mobile user is able to keep the same IP address while roaming, a live IP connection can be maintained without interruption. Glenn Research Center jointly tested the technology with Cisco, and is working to use it on low-earth-orbiting research craft. With Cisco's Mobile Networks functionality now available in Cisco IOS Software release 12.2(4)T, the commercial advantages and benefits are numerous. The technology can be applied to public safety, military/homeland security, emergency management services, railroad and shipping systems, and the automotive industry. It will allow ambulances, police, firemen, and the U.S. Coast Guard to stay connected to their networks while on the move. In the wireless battlefield, the technology will provide rapid infrastructure deployment for U.S. national defense. Airline, train, and cruise passengers utilizing Cisco Mobile Networks can fly all around the world with a continuous Internet connection. Cisco IOS(R) Software is a registered trademark of Cisco Systems.

  9. Connected correlators in quantum gravity

    International Nuclear Information System (INIS)

    We discuss the concept of connected, reparameterization invariant matter correlators in quantum gravity. We analyze the effect of discretization in two solvable cases: branched polymers and two-dimensional simplicial gravity. In both cases the naively defined connected correlators for a fixed volume display an anomalous behavior, which could be interpreted as a long-range order. We suggest that this is in fact only a highly non-trivial finite-size effect and propose an improved definition of the connected correlator, which reduces the effect. Using this definition we illustrate the appearance of a long-range spin order in the Ising model on a two-dimensional random lattice in an external magnetic field H, when H to 0 and β=βC. (author)

  10. MANAGERS CONNECTED THROUGH INFORMATION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Osmarina Pedro Garcia Garcia

    2015-06-01

    Full Text Available This study had as its central objective to ascertain how managers connect with information technology. The methodology applied was an exploratory research, through a structured questionnaire survey based on qualitative and quantitative approach. The study interviewed eighteen managers in a city in Brazil (Cascavel – Paraná, from the industrial segment distributed in several areas, selected by the non-probabilistic method, considering the samples by convenience. The research results showed that the respondents connect with information technology through social networks, applications and technological devices in a normal deliberated way. Literature has showed that Brazil is the second most connected country in social networks, which shows that managers tend to increase the use of information technology over time. We concluded that when managers use those technological tools, are online frequently, to fulfill their entrepreneurial functions, they remain attentive to everything that is happening around them and globally.

  11. Pleura: In connective tissue diseases

    Directory of Open Access Journals (Sweden)

    Kaushik Saha

    2016-01-01

    Full Text Available Connective tissue diseases (CTDs (or collagen vascular diseases represent a heterogeneous group of immunologically mediated disorders that affects many organs of the body including pleura. Frequency, presentation, and prognosis of pleural involvement depend on the underlying CTD. Connective tissue disorders may be heritable such as Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta; and autoimmune such as systemic lupus erythematosus (SLE, rheumatoid arthritis (RA, systemic sclerosis, mixed connective tissue disease (MCTD, Sjögren's syndrome (SS, dermatomyositis (DM, and polymyositis (PM. The subject of this review is to describe the variety of pleural disorders observed in the most frequent types of CTD: SLE, RA, scleroderma, SS, DM, PM, and MCTD.

  12. The solar-stellar connection

    Science.gov (United States)

    Giampapa, Mark S.

    2016-07-01

    A review of some principal results achieved in the area of stellar astrophysics with its origins in solar physics - the Solar-Stellar Connection - is presented from the perspective of an observational astronomer. The historical origins of the Solar-Stellar Connection are discussed followed by a review of key results from observations of stellar cycles analogous to the solar cycle in terms of parameters relevant to dynamo theory. A review of facets of angular momentum evolution and irradiance variations, each of which is determined by emergent, dynamo-generated magnetic fields, is given. Recent considerations of the impacts of stellar magnetic activity on the ambient radiative and energetic particle environment of the habitable zone of exoplanet systems are summarized. Some anticipated directions of the Solar-Stellar Connection in the new era of astronomy as defined by the advent of transformative facilities are presented.

  13. Brain-wide analysis of electrophysiological diversity yields novel categorization of mammalian neuron types

    OpenAIRE

    Tripathy, Shreejoy J.; Shawn D Burton; Geramita, Matthew; Gerkin, Richard C.; Nathaniel N Urban

    2015-01-01

    For decades, neurophysiologists have characterized the biophysical properties of a rich diversity of neuron types. However, identifying common features and computational roles shared across neuron types is made more difficult by inconsistent conventions for collecting and reporting biophysical data. Here, we leverage NeuroElectro, a literature-based database of electrophysiological properties (www.neuroelectro.org), to better understand neuronal diversity, both within and across neuron types,...

  14. Brain-wide slowing of spontaneous alpha rhythms in mild cognitive impairment

    Directory of Open Access Journals (Sweden)

    Pilar eGarcés

    2013-12-01

    Full Text Available The neurophysiological changes associated with Alzheimer’s Disease (AD and Mild Cognitive Impairment (MCI include an increase in low frequency activity, as measured with electroencephalography or magnetoencephalography (MEG. A relevant property of spectral measures is the alpha peak, which corresponds to the dominant alpha rhythm. Here we studied the spatial distribution of MEG resting state alpha peak frequency and amplitude values in a sample of 27 MCI patients and 24 age-matched healthy controls. Power spectra were reconstructed in source space with linearly constrained minimum variance beamformer. Then, 88 Regions of Interest (ROIs were defined and an alpha peak per ROI and subject was identified. Statistical analyses were performed at every ROI, accounting for age, sex and educational level. Peak frequency was significantly decreased (p< 0.05 in MCIs in many posterior ROIs. The average peak frequency over all ROIs was 9.68±0.71 Hz for controls and 9.05±0.90 Hz for MCIs and the average normalized amplitude was (2.57±0.59•10-2 for controls and (2.70±0.49•10-2 for MCIs. Age and gender were also found to play a role in the alpha peak, since its frequency was higher in females than in males in posterior ROIs and correlated negatively with age in frontal ROIs. Furthermore, we examined the dependence of peak parameters with hippocampal volume, which is a commonly used marker of early structural AD-related damage. Peak frequency was positively correlated with hippocampal volume in many posterior ROIs. Overall, these findings indicate a pathological alpha slowing in MCI.

  15. Brain-wide analysis of electrophysiological diversity yields novel categorization of mammalian neuron types.

    Science.gov (United States)

    Tripathy, Shreejoy J; Burton, Shawn D; Geramita, Matthew; Gerkin, Richard C; Urban, Nathaniel N

    2015-06-01

    For decades, neurophysiologists have characterized the biophysical properties of a rich diversity of neuron types. However, identifying common features and computational roles shared across neuron types is made more difficult by inconsistent conventions for collecting and reporting biophysical data. Here, we leverage NeuroElectro, a literature-based database of electrophysiological properties (www.neuroelectro.org), to better understand neuronal diversity, both within and across neuron types, and the confounding influences of methodological variability. We show that experimental conditions (e.g., electrode types, recording temperatures, or animal age) can explain a substantial degree of the literature-reported biophysical variability observed within a neuron type. Critically, accounting for experimental metadata enables massive cross-study data normalization and reveals that electrophysiological data are far more reproducible across laboratories than previously appreciated. Using this normalized dataset, we find that neuron types throughout the brain cluster by biophysical properties into six to nine superclasses. These classes include intuitive clusters, such as fast-spiking basket cells, as well as previously unrecognized clusters, including a novel class of cortical and olfactory bulb interneurons that exhibit persistent activity at theta-band frequencies.

  16. Grouted Connections with Shear Keys

    DEFF Research Database (Denmark)

    Pedersen, Ronnie; Jørgensen, M. B.; Damkilde, Lars;

    2012-01-01

    This paper presents a finite element model in the software package ABAQUS in which a reliable analysis of grouted pile-to-sleeve connections with shear keys is the particular purpose. The model is calibrated to experimental results and a consistent set of input parameters is estimated so that dif......This paper presents a finite element model in the software package ABAQUS in which a reliable analysis of grouted pile-to-sleeve connections with shear keys is the particular purpose. The model is calibrated to experimental results and a consistent set of input parameters is estimated so...

  17. 46 CFR 98.30-27 - Connections.

    Science.gov (United States)

    2010-10-01

    ... operations unless it is— (1) A bolted or full threaded connection; or (2) A quick-connect coupling accepted.... (a) Each person who makes a connection for a transfer operation shall— (1) Use suitable material in... less than four bolts in each temporary connection utilizing an American National Standards...

  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. Connecting musicological tools with Europeana

    NARCIS (Netherlands)

    van Berchum, M.

    2015-01-01

    Within the Europeana Cloud project (see http://pro.europeana.eu/web/europeana- cloud) small research groups are engaged in the development of new research tools, connected to the content present in Europeana. In 2014 a group of musicologists working on early music subjects was invited to participate

  20. Gigabit Wireless for Network Connectivity

    Science.gov (United States)

    Schoedel, Eric

    2009-01-01

    Uninterrupted, high-bandwidth network connectivity is crucial for higher education. Colleges and universities increasingly adopt gigabit wireless solutions because of their fiber-equivalent performance, quick implementation, and significant return on investment. For just those reasons, Rush University Medical Center switched from free space optics…

  1. Connecting the Dots: Rediscovering Continuity

    Science.gov (United States)

    Camenga, Kristin A.; Yates, Rebekah B. Johnson

    2014-01-01

    The topic of continuity is typically not introduced until calculus and then reexamined in real analysis. Recognizing the connections between secondary school mathematics and the advanced mathematics studied at the college level allows teachers to better identify mathematical concepts in student ideas, motivate students by piquing their curiosity,…

  2. 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....... Heref ter præsenteres de typiske årsager til, at Adobe Connect anvendes til eksamination. I forlængelse heraf gennemgås nogle scenarier for afholdelse af mundtlig eksamination i systemet. Nogle af disse scenarier suppleres med beskrivelser af deltagernes oplevelser og erfaringer med gennemførelsen af...

  3. Connecting leadership and learning: Do versatile learners make connective leaders?

    OpenAIRE

    Robinson, Jill L.

    2016-01-01

    Recent failures in leadership, suggest that creating better-quality leadership development programs is critical. In moving from theory to practice, this paper examined the relationship between learning style and leadership style which may enable us to move away from one-size-fits-all leadership development programs. Utilizing Kolb’s Experiential Learning Model and Connective Leadership theory, approximately 3600 college students were analyzed to discover whether versatility in learning styles...

  4. ConnectED: President Obama's Plan for Connecting All Schools to the Digital Age

    Science.gov (United States)

    The White House, 2013

    2013-01-01

    Driven by new digital technologies, the future of learning is increasingly interactive, individualized, and full of real-world experiences and information. Unfortunately, the average school has about the same connectivity as the average American home, but serves 200 times as many users, and fewer than 20 percent of educators say their school's…

  5. Formal connections in deformation quantization

    DEFF Research Database (Denmark)

    Masulli, Paolo

    The field of this thesis is deformation quantization, and we consider mainly symplectic manifolds equipped with a star product. After reviewing basics in complex geometry, we introduce quantization, focusing on geometric quantization and deformation quantization. The latter is defined as a star...... manifold. Gammelgaard gave an explicit formula for a class of star products in this setting. We review his construction, which is combinatorial and based on a certain family of graphs and extend it, to provide the graph formalism with the notions of composition and differentiation. We shall focus our...... products. Afterwards we study the problem of trivializing a formal connection, that is to define a differential operator on the manifold which makes any section of the bundle parallel with respect to the connection. To approach the problem we use the graph formalism described above to encode it in graph...

  6. Correlating thalamocortical connectivity and activity

    Science.gov (United States)

    da Fontoura Costa, Luciano; Sporns, Olaf

    2006-07-01

    The segregated regions of the mammalian cerebral cortex and thalamus form an extensive and complex network, whose structure and function are still only incompletely understood. The present letter describes an application of the concepts of complex networks and random walks that allows the identification of nonrandom, highly structured features of thalamocortical connections and their potential effects on dynamic interactions between cortical areas in the cat brain. Utilizing large-scale anatomical data sets of this thalamocortical system, we investigate uniform random walks in such a network by considering the steady state eigenvector of the respective stochastic matrix. It is shown that thalamocortical connections are organized in such a way as to guarantee strong correlation between the outdegree and occupancy rate (a stochastic measure potentially related to activation) of each cortical area. Possible organizational principles underlying this effect are identified and discussed.

  7. 78 FR 28626 - Te Connectivity, Industrial Division, Middletown, Pennsylvania; Te Connectivity, Corporate Shared...

    Science.gov (United States)

    2013-05-15

    ..., Corporate Shared Services Group 100 & 200 Amp Drive, Harrisburg, Pennsylvania; Te Connectivity Corporate Shared Services Group, 3700 Reidsville Road, Winston-Salem, North Carolina; Te Connectivity, Corporate Shared Services Group, 1187 Park Place, Shakopee, Minnesota; Te Connectivity, Corporate Shared...

  8. Connection between Transmission Quality Parametrs

    Directory of Open Access Journals (Sweden)

    Andrej Sulovec

    2003-01-01

    Full Text Available Errors occuring in digital transmission are the major source of degradation in that they affect voice services in terms of distortion of voice, and data type services in terms of lost or inaccurate information or reduces throughput. Therefore International Telecommunication Union ITU-T defined some objectives that enable to express the measure of digital transmission quality. It is often necessary to know the connection between these parameters.

  9. Connection between Transmission Quality Parametrs

    OpenAIRE

    Andrej Sulovec

    2003-01-01

    Errors occuring in digital transmission are the major source of degradation in that they affect voice services in terms of distortion of voice, and data type services in terms of lost or inaccurate information or reduces throughput. Therefore International Telecommunication Union ITU-T defined some objectives that enable to express the measure of digital transmission quality. It is often necessary to know the connection between these parameters.

  10. Connecting Remote Clusters with ATM

    Energy Technology Data Exchange (ETDEWEB)

    Hu, T.C.; Wyckoff, P.S.

    1998-10-01

    Sandia's entry into utilizing clusters of networked workstations is called Computational Plant or CPlant for short. The design of CPlant uses Ethernet to boot the individual nodes, Myrinet to communicate within a node cluster, and ATM to connect between remote clusters. This SAND document covers the work done to enable the use of ATM on the CPlant nodes in the Fall of 1997.

  11. The Galaxy Dark Matter Connection

    OpenAIRE

    Bosch, Frank C. van den; Yang, Xiaohu; Mo, H. J.

    2004-01-01

    What galaxy lives in what halo? The answer to this simple question holds important information regarding galaxy formation and evolution. We describe a new statistical technique to link galaxies to their dark matter haloes, or light to mass, using the clustering properties of galaxies as function of their luminosity. The galaxy-dark matter connection thus established, and parameterized through the conditional luminosity function, indicates the presence of two characteristic scales in galaxy fo...

  12. Autoimmune Hepatitis and PSC Connection.

    Science.gov (United States)

    Vergani, Diego; Mieli-Vergani, Giorgina

    2008-02-01

    This article describes the connection between autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC). The two conditions have chronicity, liver inflammation, and a positive autoimmune serology in common; they differ in terms of gender distribution and bile duct damage. There is evidence suggesting that AIH and PSC are immune-mediated diseases. PSC and AIH could lie within the spectrum of the same disease process. Future studies should determine how frequently AIH evolves to PSC.

  13. Critical Connections: Health and Academics

    OpenAIRE

    Michael, Shannon L; Merlo, Caitlin L.; Basch, Charles E.; Wentzel, Kathryn R; Wechsler, Howell

    2015-01-01

    BACKGROUND While it is a national priority to support the health and education of students, these sectors must better align, integrate, and collaborate to achieve this priority. This article summarizes the literature on the connection between health and academic achievement using the Whole School, Whole Community, and Whole Child (WSCC) framework as a way to address health-related barriers to learning. METHODS A literature review was conducted on the association between student health and aca...

  14. MANAGERS CONNECTED THROUGH INFORMATION TECHNOLOGY

    OpenAIRE

    Osmarina Pedro Garcia Garcia; Claudio Mioranza; Edison Luiz Leismann

    2015-01-01

    This study had as its central objective to ascertain how managers connect with information technology. The methodology applied was an exploratory research, through a structured questionnaire survey based on qualitative and quantitative approach. The study interviewed eighteen managers in a city in Brazil (Cascavel – Paraná), from the industrial segment distributed in several areas, selected by the non-probabilistic method, considering the samples by convenience. The research results showed...

  15. Connected Me - Proof of Concept

    OpenAIRE

    Vajravelu, Dilip Kumar

    2013-01-01

    Connected Me is a Human Body Communication (HBC) system, which is used fortransferring data through human body. The working principle is based on theorycalled Body Coupled Communication (BCC), which uses electrostatic couplingfor transferring data between device and human body. Capacitance between bodyand electrode acts as an electrical interface between devices. BCC has become aprominent research area in the field of Personal Area Network (PAN), introducedby Zimmerman in 1995. Until now ther...

  16. Functional connectivity associated with hand shape generation: Imitating novel hand postures and pantomiming tool grips challenge different nodes of a shared neural network.

    Science.gov (United States)

    Vingerhoets, Guy; Clauwaert, Amanda

    2015-09-01

    Clinical research suggests that imitating meaningless hand postures and pantomiming tool-related hand shapes rely on different neuroanatomical substrates. We investigated the BOLD responses to different tasks of hand posture generation in 14 right handed volunteers. Conjunction and contrast analyses were applied to select regions that were either common or sensitive to imitation and/or pantomime tasks. The selection included bilateral areas of medial and lateral extrastriate cortex, superior and inferior regions of the lateral and medial parietal lobe, primary motor and somatosensory cortex, and left dorsolateral prefrontal, and ventral and dorsal premotor cortices. Functional connectivity analysis revealed that during hand shape generation the BOLD-response of every region correlated significantly with every other area regardless of the hand posture task performed, although some regions were more involved in some hand postures tasks than others. Based on between-task differences in functional connectivity we predict that imitation of novel hand postures would suffer most from left superior parietal disruption and that pantomiming hand postures for tools would be impaired following left frontal damage, whereas both tasks would be sensitive to inferior parietal dysfunction. We also unveiled that posterior temporal cortex is committed to pantomiming tool grips, but that the involvement of this region to the execution of hand postures in general appears limited. We conclude that the generation of hand postures is subserved by a highly interconnected task-general neural network. Depending on task requirements some nodes/connections will be more engaged than others and these task-sensitive findings are in general agreement with recent lesion studies.

  17. Towards a comprehensive atlas of cortical connections in a primate brain: Mapping tracer injection studies of the common marmoset into a reference digital template.

    Science.gov (United States)

    Majka, Piotr; Chaplin, Tristan A; Yu, Hsin-Hao; Tolpygo, Alexander; Mitra, Partha P; Wójcik, Daniel K; Rosa, Marcello G P

    2016-08-01

    The marmoset is an emerging animal model for large-scale attempts to understand primate brain connectivity, but achieving this aim requires the development and validation of procedures for normalization and integration of results from many neuroanatomical experiments. Here we describe a computational pipeline for coregistration of retrograde tracing data on connections of cortical areas into a 3D marmoset brain template, generated from Nissl-stained sections. The procedure results in a series of spatial transformations that are applied to the coordinates of labeled neurons in the different cases, bringing them into common stereotaxic space. We applied this procedure to 17 injections, placed in the frontal lobe of nine marmosets as part of earlier studies. Visualizations of cortical patterns of connections revealed by these injections are supplied as Supplementary Materials. Comparison between the results of the automated and human-based processing of these cases reveals that the centers of injection sites can be reconstructed, on average, to within 0.6 mm of coordinates estimated by an experienced neuroanatomist. Moreover, cell counts obtained in different areas by the automated approach are highly correlated (r = 0.83) with those obtained by an expert, who examined in detail histological sections for each individual. The present procedure enables comparison and visualization of large datasets, which in turn opens the way for integration and analysis of results from many animals. Its versatility, including applicability to archival materials, may reduce the number of additional experiments required to produce the first detailed cortical connectome of a primate brain. J. Comp. Neurol. 524:2161-2181, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:27099164

  18. Testing for the dual-route cascade reading model in the brain: an fMRI effective connectivity account of an efficient reading style.

    Directory of Open Access Journals (Sweden)

    Jonathan Levy

    Full Text Available Neuropsychological data about the forms of acquired reading impairment provide a strong basis for the theoretical framework of the dual-route cascade (DRC model which is predictive of reading performance. However, lesions are often extensive and heterogeneous, thus making it difficult to establish precise functional anatomical correlates. Here, we provide a connective neural account in the aim of accommodating the main principles of the DRC framework and to make predictions on reading skill. We located prominent reading areas using fMRI and applied structural equation modeling to pinpoint distinct neural pathways. Functionality of regions together with neural network dissociations between words and pseudowords corroborate the existing neuroanatomical view on the DRC and provide a novel outlook on the sub-regions involved. In a similar vein, congruent (or incongruent reliance of pathways, that is reliance on the word (or pseudoword pathway during word reading and on the pseudoword (or word pathway during pseudoword reading predicted good (or poor reading performance as assessed by out-of-magnet reading tests. Finally, inter-individual analysis unraveled an efficient reading style mirroring pathway reliance as a function of the fingerprint of the stimulus to be read, suggesting an optimal pattern of cerebral information trafficking which leads to high reading performance.

  19. MOHCS: Towards Mining Overlapping Highly Connected Subgraphs

    CERN Document Server

    Lin, Xiahong; Chen, Kefei; Chiu, David K Y

    2008-01-01

    Many networks in real-life typically contain parts in which some nodes are more highly connected to each other than the other nodes of the network. The collection of such nodes are usually called clusters, communities, cohesive groups or modules. In graph terminology, it is called highly connected graph. In this paper, we first prove some properties related to highly connected graph. Based on these properties, we then redefine the highly connected subgraph which results in an algorithm that determines whether a given graph is highly connected in linear time. Then we present a computationally efficient algorithm, called MOHCS, for mining overlapping highly connected subgraphs. We have evaluated experimentally the performance of MOHCS using real and synthetic data sets from computer-generated graph and yeast protein network. Our results show that MOHCS is effective and reliable in finding overlapping highly connected subgraphs. Keywords-component; Highly connected subgraph, clustering algorithms, minimum cut, m...

  20. Connecting Related Rates and Differential Equations

    Science.gov (United States)

    Brandt, Keith

    2012-01-01

    This article points out a simple connection between related rates and differential equations. The connection can be used for in-class examples or homework exercises, and it is accessible to students who are familiar with separation of variables.

  1. Linear connections on the quantum plane

    OpenAIRE

    Dubois-Violette, Michel; Madore, John; Masson, Thierry; Mourad, Jihad

    1994-01-01

    A general definition has been proposed recently of a linear connection and a metric in noncommutative geometry. It is shown that to within normalization there is a unique linear connection on the quantum plane and there is no metric.

  2. Embedded adhesive connection for laminated glass plates

    DEFF Research Database (Denmark)

    Hansen, Jens Zangenberg; Poulsen, S.H.; Bagger, A.;

    2012-01-01

    The structural behavior of a new connection design, the embedded adhesive connection, used for laminated glass plates is investigated. The connection consists of an aluminum plate encapsulated in-between two adjacent triple layered laminated glass plates. Fastening between glass and aluminum...... usage in a design situation. The embedded connection shows promising potential as a future fastening system for load-carrying laminated glass plates....

  3. Fatigue Assessment of Threaded Riser Connections

    OpenAIRE

    Braun, Moritz,

    2014-01-01

    Threaded connections as found in applications like rigid riser, drillstrings, and workover riser are manufactured with sharp notches. Subjected to cyclic loading, those notches lead to high stress concentrations, which increase the risk of fatigue crack initiation significantly. A common connection type that has been the basis for extensive studies is the API Line Pipe connection. The basic API thread type consists of truncated triangular threads. In order to tighten the connection the male a...

  4. Connectivity in Autism: A review of MRI connectivity studies

    Science.gov (United States)

    Rane, Pallavi; Cochran, David; Hodge, Steven M.; Haselgrove, Christian; Kennedy, David; Frazier, Jean A.

    2016-01-01

    Autism Spectrum Disorder (ASD) affects 1 in 50 children between the ages of 6–17 years as per a 2012 CDC survey of parents. The etiology of ASD is not precisely known. ASD is an umbrella term, which includes low (IQ70) individuals. A better understanding of the disorder, and how it manifests in an individual subject can lead to more effective intervention plans to fulfill the individual’s treatment needs. Magnetic resonance imaging (MRI) is a non-invasive investigational tool that can help study the ways in which the brain develops and/or deviates from the typical developmental trajectory. MRI offers insights into the structure, function, and metabolism of the brain. In this article, we review published studies on brain connectivity changes in ASD using either resting state functional MRI or diffusion tensor imaging. The general findings of decreases in white matter integrity and long-range neural coherence are prevalent in ASD literature. However, there is somewhat less of a consensus in the detailed localization of these findings. There are even fewer studies linking these connectivity alterations with the behavioral phenotype of the disorder. Nevertheless, with the help of data sharing and large-scale analytic efforts, the field is advancing towards several convergent themes. These include reduced functional coherence of long-range intra-hemispheric cortico-cortical default mode circuitry, impaired inter-hemispheric regulation, and an associated, perhaps compensatory, increase in local and short-range cortico-subcortical coherence. PMID:26146755

  5. 46 CFR 64.33 - Pipe connection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Pipe connection. 64.33 Section 64.33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Standards for an MPT § 64.33 Pipe connection. Each pipe connection that is not a...

  6. Connectivity Changes in Parkinson's Disease.

    Science.gov (United States)

    Cerasa, Antonio; Novellino, Fabiana; Quattrone, Aldo

    2016-10-01

    Parkinson's disease (PD) is a chronic and progressive movement disorder of the central nervous system characterized by widespread alterations in several non-motor aspects such as mood, sleep, olfactory, and cognition in addition to motor dysfunctions. Advanced neuroimaging using functional connectivity reconstruction of the human brain has provided a vast knowledge on the pathophysiological mechanisms underlying this disorder, but this, however, does not cover the overall inter-/intra-individual variability of PD phenotypes. The present review is aimed at discussing to what extent the evidence provided by group-based neuroimaging analysis in this field of study (using seed-based, network-based, or graph theory approaches) may be generalized. In particular, we summarized the literature on the application of resting-state functional connectivity studies to explore different neural correlates of motor and non-motor symptoms of PD and the neural mechanisms involved in treatment effects: effects of levodopa or deep brain stimulation. The lesson learnt from one decade of studies provides consistent evidence on the role of the altered communication between the striato-frontal pathways as a marker of PD-related motor degeneration, whereas in the non-motor domain, several missing pieces of a complex puzzle are provided. However, the main target is to present a new era of intelligent neuroimaging applications, where automated multivariate analysis of functional connectivity data may be used for moving from group-level statistical results to personalized predictions in a clinical setting. Although in its relative infancy, the evidence gathered so far suggests a new era of clinical neuroimaging is starting. PMID:27568202

  7. Connectivity graphs of uncertainty regions

    CERN Document Server

    Chambers, Erin; Lenchner, Jonathan; Sember, Jeff; Srinivasan, Venkatesh; Stege, Ulrike; Stolpner, Svetlana; Weibel, Christophe; Whitesides, Sue

    2010-01-01

    We study a generalization of the well known bottleneck spanning tree problem called "Best Case Connectivity with Uncertainty": Given a family of geometric regions, choose one point per region, such that the length of the longest edge in a spanning tree of a disc intersection graph is minimized. We show that this problem is NP-hard even for very simple scenarios such as line segments and squares. We also give exact and approximation algorithms for the case of line segments and unit discs respectively.

  8. Women's connectivity in extreme networks.

    Science.gov (United States)

    Manrique, Pedro; Cao, Zhenfeng; Gabriel, Andrew; Horgan, John; Gill, Paul; Qi, Hong; Restrepo, Elvira M; Johnson, Daniela; Wuchty, Stefan; Song, Chaoming; Johnson, Neil

    2016-06-01

    A popular stereotype is that women will play more minor roles than men as environments become more dangerous and aggressive. Our analysis of new longitudinal data sets from offline and online operational networks [for example, ISIS (Islamic State)] shows that although men dominate numerically, women emerge with superior network connectivity that can benefit the underlying system's robustness and survival. Our observations suggest new female-centric approaches that could be used to affect such networks. They also raise questions about how individual contributions in high-pressure systems are evaluated. PMID:27386564

  9. The Cosmology - Particle Physics Connection

    CERN Document Server

    Trodden, M

    2006-01-01

    Modern cosmology poses deep and unavoidable questions for fundamental physics. In this plenary talk, delivered in slightly different forms at the {\\it Particles and Nuclei International Conference} (PANIC05) in Santa Fe, in October 2005, and at the {\\it CMB and Physics of the Early Universe International Conference}, on the island of Ischia, Italy, in April 2006, I discuss the broad connections between cosmology and particle physics, focusing on physics at the TeV scale, accessible at the next and future generations of colliders

  10. Adobe Connect Pro ohjauksen apuna

    OpenAIRE

    Koukkari, Katja

    2010-01-01

    Tämän kehittämistyön tavoitteena on tarkastella, miten suunnittelijat ja opiskelijat kokevat Adobe Connect Pro -ohjelman käytön ohjauksen apuna sekä miten käytettävä ohjelma on sekä teknisesti että pedagogisesti. Teoriaosuudessa tarkastelen mm. sulautuvaa opetusta ja verkko-ohjauksen erityispiirteitä. Internet tarjoaa mahdollisuuksia sekä eriaikaiseen että reaaliaikaiseen viestintään. Perinteisesti verkkokurssin viestintä on ollut eriaikaista tekstipohjaisuuteen perustuvaa viestintää. Nykyisi...

  11. Study of rectenna array connection

    Energy Technology Data Exchange (ETDEWEB)

    Miura, T.; Shinohara, N.; Matsumoto, H. [Kyoto Univ., Uji (Japan). Engineering Research Inst.

    1997-11-01

    A study was conducted in which a new rectenna working at 2.45 GHz microwave was developed for ground-to-ground microwave power transmission. The new rectenna consists of an antenna section and a rectifying section. The new design is simple and therefore more accurate than a micro-strip type patch antenna. The efficiency of conversion of microwave power to direct current depends on the mutual dependence of antenna elements and circuit conditions of rectifying sections. A series of experiments were conducted to analyze the rectenna characteristics and a method for efficiently connecting rectenna arrays was proposed. 3 refs., 2 tabs., 15 figs.

  12. New molecular connections in angiogenesis

    Institute of Scientific and Technical Information of China (English)

    Qiling Xu; David Wilkinson

    2010-01-01

    @@ In vertebrates, oxygen and nutrients are delivered to tissues by the circula-tion of blood through vessels, comprised of a branched network of endothelial tubes termed the vasculature. Crucial for the formation of blood vessels during development is the process of angiogenesis, in which new sprouts form from pre-existing vessels in a complex cascade of cellular events. This involves the activation of an endothelial cell in the vessel to become a highly exploratory 'tip' cell that migrates to invade the surrounding tissues, while remaining tightly connected to the fol-lowing cells that subsequently generate the tubular structures of a new vessel.

  13. A Building Connecting Separated Communities

    DEFF Research Database (Denmark)

    Axel, Erik

    abroad was constructed by different professional groups architects/engineers/craft persons, and how it was used by some groupings of students. In the beginning of the construction process our interviews with the architects revealed that the architect designing the house collaborated with an architect...... 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...

  14. Behavior of concentrically loaded CFT braces connections

    Directory of Open Access Journals (Sweden)

    Maha M. Hassan

    2014-03-01

    Full Text Available Concrete filled tubes (CFTs composite columns have many economical and esthetic advantages, but the behavior of their connections is complicated. Through this study, it is aimed to investigate the performance and behavior of different connection configurations between concrete filled steel tube columns and bracing diagonals through an experimental program. The study included 12 connection subassemblies consisting of a fixed length steel tube and gusset plate connected to the tube end with different details tested under half cyclic loading. A notable effect was observed on the behavior of the connections due to its detailing changes with respect to capacity, failure mode, ductility, and stress distribution.

  15. Making connections: reflection, feedback and support

    Directory of Open Access Journals (Sweden)

    Jane Seale

    2007-12-01

    Full Text Available Hansell (1974 conceptualized seven different connections or attachments that we have to the world in which we live: attachments that consist of connections to other people, to a social role as well as to a system of meaning. For many, learning is at the heart of the process of making connections, particularly meaningful connections (Horton, 2000. If this is true, then it leads us to consider the extent to which educators, the systems they work in and the tools they use have a role to play in helping learners make those meaningful connections. For example, Scherer (2002, p. 5 suggests that educational systems have a responsibility to:

  16. Generalized magnetofluid connections in relativistic magnetohydrodynamics.

    Science.gov (United States)

    Asenjo, Felipe A; Comisso, Luca

    2015-03-20

    The concept of magnetic connections is extended to nonideal relativistic magnetohydrodynamical plasmas. Adopting a general set of equations for relativistic magnetohydrodynamics including thermal-inertial, thermal electromotive, Hall, and current-inertia effects, we derive a new covariant connection equation showing the existence of generalized magnetofluid connections that are preserved during the dissipationless plasma dynamics. These connections are intimately linked to a general antisymmetric tensor that unifies the electromagnetic and fluid fields, allowing the extension of the magnetic connection notion to a much broader concept. PMID:25839284

  17. Generalized magnetofluid connections in pair plasmas

    International Nuclear Information System (INIS)

    We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found

  18. Generalized magnetofluid connections in pair plasmas

    Science.gov (United States)

    Asenjo, Felipe A.; Comisso, Luca; Mahajan, Swadesh M.

    2015-12-01

    We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found.

  19. Generalized Magnetofluid Connections in Pair Plasmas

    CERN Document Server

    Asenjo, Felipe A; Mahajan, Swadesh M

    2015-01-01

    We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found.

  20. Generalized magnetofluid connections in pair plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Asenjo, Felipe A., E-mail: felipe.asenjo@uai.cl [Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Santiago 7941169 (Chile); Comisso, Luca, E-mail: lcomisso@princeton.edu [Department of Astrophysical Sciences and Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08544 (United States); Dipartimento Energia, Politecnico di Torino, Torino 10129, Italy and Istituto dei Sistemi Complessi-CNR, Roma 00185 (Italy); Mahajan, Swadesh M., E-mail: mahajan@mail.utexas.edu [Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2015-12-15

    We extend the magnetic connection theorem of ideal magnetohydrodynamics to nonideal relativistic pair plasmas. Adopting a generalized Ohm's law, we prove the existence of generalized magnetofluid connections that are preserved by the plasma dynamics. We show that these connections are related to a general antisymmetric tensor that unifies the electromagnetic and fluid fields. The generalized magnetofluid connections set important constraints on the plasma dynamics by forbidding transitions between configurations with different magnetofluid connectivity. An approximated solution is explicitly shown where the corrections due to current inertial effects are found.

  1. A theory of alpha/theta neurofeedback, creative performance enhancement, long distance functional connectivity and psychological integration.

    Science.gov (United States)

    Gruzelier, John

    2009-02-01

    Professionally significant enhancement of music and dance performance and mood has followed training with an EEG-neurofeedback protocol which increases the ratio of theta to alpha waves using auditory feedback with eyes closed. While originally the protocol was designed to induce hypnogogia, a state historically associated with creativity, the outcome was psychological integration, while subsequent applications focusing on raising the theta-alpha ratio, reduced depression and anxiety in alcoholism and resolved post traumatic stress syndrome (PTSD). In optimal performance studies we confirmed associations with creativity in musical performance, but effects also included technique and communication. We extended efficacy to dance and social anxiety. Diversity of outcome has a counterpart in wide ranging associations between theta oscillations and behaviour in cognitive and affective neuroscience: in animals with sensory-motor activity in exploration, effort, working memory, learning, retention and REM sleep; in man with meditative concentration, reduced anxiety and sympathetic autonomic activation, as well as task demands in virtual spatial navigation, focussed and sustained attention, working and recognition memory, and having implications for synaptic plasticity and long term potentiation. Neuroanatomical circuitry involves the ascending mescencephalic-cortical arousal system, and limbic circuits subserving cognitive as well as affective/motivational functions. Working memory and meditative bliss, representing cognitive and affective domains, respectively, involve coupling between frontal and posterior cortices, exemplify a role for theta and alpha waves in mediating the interaction between distal and widely distributed connections. It is posited that this mediation in part underpins the integrational attributes of alpha-theta training in optimal performance and psychotherapy, creative associations in hypnogogia, and enhancement of technical, communication and

  2. Altered brain morphology and functional connectivity reflect a vulnerable affective state after cumulative multigenerational stress in rats.

    Science.gov (United States)

    McCreary, J Keiko; Truica, L Sorina; Friesen, Becky; Yao, Youli; Olson, David M; Kovalchuk, Igor; Cross, Albert R; Metz, Gerlinde A S

    2016-08-25

    Prenatal stress is a risk factor for abnormal neuroanatomical, cognitive, behavioral and mental health outcomes with potentially transgenerational consequences. Females in general seem more resilient to the effects of prenatal stress than males. Here, we examined if repeated stress across generations may diminish stress resiliency and cumulatively enhance the susceptibility for adverse health outcomes in females. Pregnant female rats of three successive generations were exposed to stress from gestational days 12-18 to generate multigenerational prenatal stress (MPS) in the maternal lineage. Stress response was measured by plasma corticosterone levels and open-field exploration in each generation. Neuromorphological consequences of MPS were investigated in the F3 generation using in vivo manganese-enhanced magnetic resonance imaging (MEMRI), T2-relaxometry, and cytoarchitectonics in relation to candidate gene expression involved in brain plasticity and mental health. Each additional generation of prenatal stress incrementally elevated hypothalamic-pituitary-adrenal axis activation, anxiety-like and aversive behaviors in adult female offspring. Elevated stress responses in the MPS F3 generation were accompanied by reduced neural density in prefrontal cortex, hippocampus and whole brain along with altered brain activation patterns in in vivo MEMRI. MPS increased ephrin receptor A5 (Epha5), neuronal growth regulator (Negr1) and synaptosomal-associated protein 25 (Snap25) gene expression and reduced fibroblast growth factor 12 (Fgf12) in prefrontal cortex. These genes regulate neuronal maturation, arborization and synaptic plasticity and may explain altered brain cytoarchitectonics and connectivity. These findings emphasize that recurrent stress across generations may cumulatively increase stress vulnerability and the risk of adverse health outcomes through perinatal programing in females. PMID:27241944

  3. Connectivity editing for quadrilateral meshes

    KAUST Repository

    Peng, Chihan

    2011-12-12

    We propose new connectivity editing operations for quadrilateral meshes with the unique ability to explicitly control the location, orientation, type, and number of the irregular vertices (valence not equal to four) in the mesh while preserving sharp edges. We provide theoretical analysis on what editing operations are possible and impossible and introduce three fundamental operations to move and re-orient a pair of irregular vertices. We argue that our editing operations are fundamental, because they only change the quad mesh in the smallest possible region and involve the fewest irregular vertices (i.e., two). The irregular vertex movement operations are supplemented by operations for the splitting, merging, canceling, and aligning of irregular vertices. We explain how the proposed highlevel operations are realized through graph-level editing operations such as quad collapses, edge flips, and edge splits. The utility of these mesh editing operations are demonstrated by improving the connectivity of quad meshes generated from state-of-art quadrangulation techniques. © 2011 ACM.

  4. Connectivity editing for quadrilateral meshes

    KAUST Repository

    Peng, Chihan

    2011-12-01

    We propose new connectivity editing operations for quadrilateral meshes with the unique ability to explicitly control the location, orientation, type, and number of the irregular vertices (valence not equal to four) in the mesh while preserving sharp edges. We provide theoretical analysis on what editing operations are possible and impossible and introduce three fundamental operations to move and re-orient a pair of irregular vertices. We argue that our editing operations are fundamental, because they only change the quad mesh in the smallest possible region and involve the fewest irregular vertices (i.e., two). The irregular vertex movement operations are supplemented by operations for the splitting, merging, canceling, and aligning of irregular vertices. We explain how the proposed high-level operations are realized through graph-level editing operations such as quad collapses, edge flips, and edge splits. The utility of these mesh editing operations are demonstrated by improving the connectivity of quad meshes generated from state-of-art quadrangulation techniques.

  5. Astrophysicists' conversational connections on Twitter.

    Directory of Open Access Journals (Sweden)

    Kim Holmberg

    Full Text Available Because Twitter and other social media are increasingly used for analyses based on altmetrics, this research sought to understand what contexts, affordance use, and social activities influence the tweeting behavior of astrophysicists. Thus, the presented study has been guided by three research questions that consider the influence of astrophysicists' activities (i.e., publishing and tweeting frequency and of their tweet construction and affordance use (i.e. use of hashtags, language, and emotions on the conversational connections they have on Twitter. We found that astrophysicists communicate with a variety of user types (e.g. colleagues, science communicators, other researchers, and educators and that in the ego networks of the astrophysicists clear groups consisting of users with different professional roles can be distinguished. Interestingly, the analysis of noun phrases and hashtags showed that when the astrophysicists address the different groups of very different professional composition they use very similar terminology, but that they do not talk to each other (i.e. mentioning other user names in tweets. The results also showed that in those areas of the ego networks that tweeted more the sentiment of the tweets tended to be closer to neutral, connecting frequent tweeting with information sharing activities rather than conversations or expressing opinions.

  6. Content, Context & Connectivity Persuasive Interplay

    DEFF Research Database (Denmark)

    Sørensen, Christian Grund

    2013-01-01

    The aim of this paper is to discuss the relationship between content, context and connectivity and suggesting a model of Dynamic Interplay. This is done in relation to a specific learning environment concerning cultural mediation, in casu the Kaj Munk Case of the EuroPLOT-project (an EU-supported......The aim of this paper is to discuss the relationship between content, context and connectivity and suggesting a model of Dynamic Interplay. This is done in relation to a specific learning environment concerning cultural mediation, in casu the Kaj Munk Case of the EuroPLOT-project (an EU...... is discussed. Focus is here on The Kaj Munk Study Edition, The Conceptual Pond, Immersive Layers Design, and Generative Learning Objects (GLOs) which are applications affiliated with the Munk case. This paper explores the persuasive potential of the interplay between the different applications for the benefit...... of learning and reflection and a model of Dynamic Interplay is introduced. This is done with a primary inspiration from rhetoric particularly in the shape of the Aptum model and a focus on kairos. Possible benefits of this approach are discussed and several questions for further research are suggested....

  7. Investigation into Methods for Predicting Connection Temperatures

    Directory of Open Access Journals (Sweden)

    K. Anderson

    2009-01-01

    Full Text Available The mechanical response of connections in fire is largely based on material strength degradation and the interactions between the various components of the connection. In order to predict connection performance in fire, temperature profiles must initially be established in order to evaluate the material strength degradation over time. This paper examines two current methods for predicting connection temperatures: The percentage method, where connection temperatures are calculated as a percentage of the adjacent beam lower-flange, mid-span temperatures; and the lumped capacitance method, based on the lumped mass of the connection. Results from the percentage method do not correlate well with experimental results, whereas the lumped capacitance method shows much better agreement with average connection temperatures. A 3D finite element heat transfer model was also created in Abaqus, and showed good correlation with experimental results. 

  8. Random geometric graphs with general connection functions

    Science.gov (United States)

    Dettmann, Carl P.; Georgiou, Orestis

    2016-03-01

    In the original (1961) Gilbert model of random geometric graphs, nodes are placed according to a Poisson point process, and links formed between those within a fixed range. Motivated by wireless ad hoc networks "soft" or "probabilistic" connection models have recently been introduced, involving a "connection function" H (r ) that gives the probability that two nodes at distance r are linked (directly connect). In many applications (not only wireless networks), it is desirable that the graph is connected; that is, every node is linked to every other node in a multihop fashion. Here the connection probability of a dense network in a convex domain in two or three dimensions is expressed in terms of contributions from boundary components for a very general class of connection functions. It turns out that only a few quantities such as moments of the connection function appear. Good agreement is found with special cases from previous studies and with numerical simulations.

  9. STRENGTH DESIGN OF PREMIUM THREADED CASING CONNECTION

    Institute of Scientific and Technical Information of China (English)

    Gao Lianxin; Jin Ye; Zhang Yi

    2004-01-01

    Using premium casing connections instead of API ones is one of the most effective technique to prevent casing failure.The factors contribute to the strength of premium casing connections are studied with FEA and full-scale test.The criterions are presented that ensure the connection's strength higher than the pipe.At the same time, the method is given to decrease the peak stress of the connection so as to improve its anticorruption property.At last, full-scale tests are done to test the strength of the connections designed with the method described, the results show that the connection's strength is higher than the pipe.This indicated that the method described is effective in designing premium casing connection.

  10. Food-associated cues alter forebrain functional connectivity as assessed with immediate early gene and proenkephalin expression

    Directory of Open Access Journals (Sweden)

    Landry Charles F

    2007-04-01

    Full Text Available Abstract Background Cues predictive of food availability are powerful modulators of appetite as well as food-seeking and ingestive behaviors. The neurobiological underpinnings of these conditioned responses are not well understood. Monitoring regional immediate early gene expression is a method used to assess alterations in neuronal metabolism resulting from upstream intracellular and extracellular signaling. Furthermore, assessing the expression of multiple immediate early genes offers a window onto the possible sequelae of exposure to food cues, since the function of each gene differs. We used immediate early gene and proenkephalin expression as a means of assessing food cue-elicited regional activation and alterations in functional connectivity within the forebrain. Results Contextual cues associated with palatable food elicited conditioned motor activation and corticosterone release in rats. This motivational state was associated with increased transcription of the activity-regulated genes homer1a, arc, zif268, ngfi-b and c-fos in corticolimbic, thalamic and hypothalamic areas and of proenkephalin within striatal regions. Furthermore, the functional connectivity elicited by food cues, as assessed by an inter-regional multigene-expression correlation method, differed substantially from that elicited by neutral cues. Specifically, food cues increased cortical engagement of the striatum, and within the nucleus accumbens, shifted correlations away from the shell towards the core. Exposure to the food-associated context also induced correlated gene expression between corticostriatal networks and the basolateral amygdala, an area critical for learning and responding to the incentive value of sensory stimuli. This increased corticostriatal-amygdalar functional connectivity was absent in the control group exposed to innocuous cues. Conclusion The results implicate correlated activity between the cortex and the striatum, especially the nucleus

  11. Dual Authentication For Bluetooth Connection

    Directory of Open Access Journals (Sweden)

    Diallo Alhassane Saliou

    2014-07-01

    Full Text Available Recently, Bluetooth technology is widely used by organizations and individuals to provide wireless personal area network (WPAN. This is because the radio frequency (RF waves can easily penetrate obstacles and can propagate without direct line-of-sight (LoS. These two characteristics have led to replace wired communication by wireless systems. However, there are serious security challenges associated with wireless communication systems because they are easier to eavesdrop, disrupt and jam than the wired systems. Bluetooth technology started with a form of pairing called legacy pairing prior to any communication. However, due to the serious security issues found in the legacy pairing, a secure and simple pairing called SPP was announced with Bluetooth 2.1 and later since 2007. SPP has solved the main security issue which is the weaknesses of the PIN code in the legacy pairing, however it has been found with some vulnerabilities such as eavesdropping and man-in-the-middle (MITM attacks. Since the discovery of these vulnerabilities, some enhancements have been proposed to the Bluetooth Specification Interest Group (SIG which is the regulatory body of Bluetooth technology; nevertheless, some proposed enhancements are ineffective or are not yet implemented by Manufacturers. Therefore, an improvement of the security authentication in Bluetooth connection is highly required to overcome the existing drawbacks. This proposed protocol uses Hash-based Message Authentication Code (HMAC algorithm with Secure Hash Algorithm (SHA-256. The implementation of this proposal is based on the Arduino Integrated Development Environment (IDE as software and a Bluetooth (BT Shield connected to an Arduino Uno R3 boards as hardware. The result was verified on a Graphical User Interface (GUI built in Microsoft Visual Studio 2010 with C sharp as default environment. It has shown that the proposed scheme works perfectly with the used hardware and software. In addition, the

  12. Unity connecting module in SSPF

    Science.gov (United States)

    1998-01-01

    In the Space Station Processing Facility, the Unity connecting module, part of the International Space Station, is shown with Pressurized Mating Adapters 1 (left) and 2 (right) attached. Unity is scheduled to undergo testing of the common berthing mechanism to which other space station elements will dock. Unity is the primary payload on mission STS-88, targeted to launch Dec. 3, 1998. Other testing includes the Pad Demonstration Test to verify the compatibility of the module with the Space Shuttle as well as the ability of the astronauts to send and receive commands to Unity from the flight deck of the orbiter. Unity is expected to be ready for installation into the payload canister on Oct. 25, and transported to Launch Pad 39-A on Oct. 27. The Unity will be mated to the Russian-built Zarya control module which should already be in orbit at that time.

  13. Galaxy Morphology - Halo Gas Connections

    CERN Document Server

    Kacprzak, G G; Steidel, C C; Kacprzak, Glenn G.; Churchill, Christopher W.; Steidel, Charles C.

    2005-01-01

    We studied a sample of 38 intermediate redshift MgII absorption-selected galaxies using (1) Keck/HIRES and VLT/UVES quasar spectra to measure the halo gas kinematics from MgII absorption profiles and (2) HST/WFPC-2 images to study the absorbing galaxy morphologies. We have searched for correlations between quantified gas absorption properties, and host galaxy impact parameters, inclinations, position angles, and quantified morphological parameters. We report a 3.2-sigma correlation between asymmetric perturbations in the host galaxy morphology and the MgII absorption equivalent width. We suggest that this correlation may indicate a connection between past merging and/or interaction events in MgII absorption-selected galaxies and the velocity dispersion and quantity of gas surrounding these galaxies.

  14. Method for hermetic electrical connections

    Science.gov (United States)

    Monroe, Saundra L.; Glass, S. Jill; Stone, Ronnie G.; Bond, Jamey T.; Susan, Donald F.

    2011-12-27

    A method of providing a hermetic, electrical connection between two electrical components by mating at least one metal pin in a glass-ceramic to metal seal connector to two electrical components, wherein the glass-ceramic to metal seal connector incorporates at least one metal pin encased (sealed) in a glass-ceramic material inside of a metal housing, with the glass-ceramic material made from 65-80% SiO.sub.2, 8-16% Li.sub.2O, 2-8% Al.sub.2O.sub.3, 1-5% P.sub.2O.sub.5, 1-8% K.sub.2O, 0.5-7% B.sub.2O.sub.3, and 0-5% ZnO. The connector retains hermeticity at temperatures as high as 700.degree. C. and pressures as high as 500 psi.

  15. Proliferating Connections and Communicating Convergence

    Directory of Open Access Journals (Sweden)

    Aylish Wood

    2008-01-01

    Full Text Available In this paper I use the work of Niklas Luhmann to explore what pressure the concept of convergence exerts over how we communicate about the changing expressive practices of digital games following the emergence of digital technologies. My claim will be that in its current form, convergence privileges either the human users of technological platforms, or the combination of aesthetic conventions from different media what connects is either the user or the aesthetic code. While neither of these two positions would be likely to deny a reliance on the interplay between humans and technologies, such an interplay is taken for granted rather than explored. By using Luhmann’s version of systems theory, I argue that we can more effectively grasp the interplay of human and technological participants by understanding their combined roles in changing expressive practices.

  16. 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

  17. 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.

  18. 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

  19. Local Natural Connectivity in Complex Networks

    Institute of Scientific and Technical Information of China (English)

    SHANG Yi-Lun

    2011-01-01

    @@ In network theory, a complex network represents a system whose evolving structure and dynamic behavior contribute to its robustness.The natural connectivity is recently proposed as a spectral measure to characterize the robustness of complex networks.We decompose the natural connectivity of a network as local natural connectivity of its connected components and quantify their contributions to the network robustness.In addition, we compare the natural connectivity of a network with that of an induced subgraph of it based on interlacing theorems.As an application, we derive an inequality for eigenvalues of ErdSs-Renyi random graphs.%In network theory, a complex network represents a system whose evolving structure and dynamic behavior contribute to its robustness. The natural connectivity is recently proposed as a spectral measure to characterize the robustness of complex networks. We decompose the natural connectivity of a network as local naturai connectivity of its connected components and quantify their contributions to the network robustness. In addition, we compare the naturai connectivity of a network with that of an induced subgraph of it based on interlacing theorems. As an application, we derive an inequality for eigenvalues of Erdos-Renyi random graphs.

  20. [Connective tissue and prolapse genesis].

    Science.gov (United States)

    Tremollieres, F

    2010-06-01

    The pathophysiology of pelvic floor disorders still remains not well understood. Increasing age as well as vaginal multiparity are the main commonly accepted factors. The hypothesis of a defect of connective tissues of the pelvic floor with aging due to collagen deficiency and/or elastic fiber degradation is often highlighted. The issue of a potential protective role of HRT is also discussed although the recent results from the WHI would suggest a negative impact of HRT on urinary incontinence, especially when HRT is initiated in elderly women, far from the menopause. Nevertheless, environmental factors cannot explain the full pathogenesis of pelvic organ prolapse (POP) and the contribution of genetic factors to the development of pelvic floor disorders is widely recognized. Support for a genetic influence on POP derives from reports suggesting that heritability is a strong contributing factor and a familial history of POP is considered as a classical risk factor. However, the characterization of the underlying molecular mechanisms remains limited, since POP may be considered the end result of a multifactorial process leading to destruction of vaginal wall connective tissue. Experimental studies in mice with null mutations in the genes encoding different putative factors involved in elastic fibers remodeling and homeostasis are crucial in the understanding of the pathogenesis of POP. Mice with null mutation in the gene encoding lysyl oxidase-like 1 (LOXL1) or fibulin-5, demonstrate signs of elastinopathy including the development of a POP in the postpartum. Likewise, homeobox genes such as HOXA11, which are essential in the embryonic development of the urogenital tract might also be involved in the pathogenesis of POP. The better understanding of the underlying determinants of pelvic floor disorders with a special focus on genetic factors may offer new therapeutic strategies, in addition to or replacement of surgical procedures.

  1. Boundary effects in welded steel moment connections

    Science.gov (United States)

    Lee, Kyoung-Hyeog

    Unprecedented widespread failure of welded moment connections in steel frames caused by the 1994 Northridge and the 1995 Kobe earthquakes have alarmed the engineering communities throughout the world. Welded moment connections in steel frames have been traditionally designed by using the classical beam theory which leads to assumptions that the flanges transfer moment while the web connection primarily resists the shear force. However, this study shows that the magnitude and direction of the principal stresses in the connection region are better approximated by using truss analogy rather than the classical beam theory. Accordingly, both the bending moment and the shear force are transferred across the connection near the beam flanges through diagonal strut action. Thus, the beam flange region of the traditionally designed connection is overloaded. This conclusion explains, to a large extent, the recently observed steel moment connection failures. In this study, detailed finite element analyses were carried out for a representative beam-to-column subassemblage with fully welded connection. The stress distribution in the beam web and flanges in the vicinity of the connection were closely studied. The factors responsible for stress redistribution and concentration were identified by using fundamental principles of mechanics. It was concluded that peak resultant stresses can exceed the values used in simple design calculations by large margins. Using the finite element analysis results and the truss analogy to establish a realistic load path in the connection, a practical and more rational analysis and design procedure was developed. The proposed design procedure and the new connection details were successfully validated through cyclic load testing of a nearly full size specimen. The truss model represented the force transmission around the beam-to-column moment connection region very well. Results of the finite element analyses and the laboratory testing showed

  2. Formal Connections for families of Star Products

    DEFF Research Database (Denmark)

    Ellegaard Andersen, Jørgen; Masulli, Paolo; Schaetz, Florian

    We define the notion of a formal connection for a smooth family of star products with fixed underlying symplectic structure. Such a formal connection allows one to relate star products at different points in the family. This generalizes the formal Hitchin connection introduced by the first author....... We establish a necessary and sufficient condition that guarantees the existence of a formal connection, and we describe the space of formal connections for a family as an affine space modelled by the derivations of the star products. Moreover we show that if the parameter space has trivial first...... cohomology group any two flat formal connections are related by an automorphism of the family of star products....

  3. Connectivity analysis of controlled quantum systems

    Science.gov (United States)

    Wu, Rong; Rabitz, Herschel; Turinici, Gabriel; Sola, Ignacio

    2004-11-01

    A connectivity analysis of controlled quantum systems assesses the feasibility of a field existing that can transfer at least some amplitude between any specified pair of states. Although Hamiltonians with special structure or symmetry may not produce full connectivity, it is argued and demonstrated that virtually any Hamiltonian is expected to be connected. The connectivity of any particular system is generally revealed in the quantum evolution over a single or at most a few time steps. A connectivity analysis is inexpensive to perform and it can also identify statistically significant intermediate states linking a specified initial and final state. These points are illustrated with several simple systems. The likelihood of an arbitrary system being connected implies that at least some product yield can be expected in the laboratory for virtually all systems subjected to a suitable control.

  4. Modeling of preloaded threaded pipe connections

    OpenAIRE

    Van Wittenberghe, Jeroen; DE BAETS, Patrick; De Waele, Wim

    2009-01-01

    In this paper a modeling method to perform parametric studies on preloaded threaded connections is presented. The method uses a non-linear 2D axisymmetric finite element model, and is illustrated by a parametric study of an API Line Pipe connection. The method was used to quantify the influence of the coefficient of friction, the wall thickness of pin and box and the box recess length of the connection.

  5. Review on Cold-Formed Steel Connections

    OpenAIRE

    Yeong Huei Lee; Cher Siang Tan; Shahrin Mohammad; Mahmood Md. Tahir; Poi Ngian Shek

    2014-01-01

    The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connection...

  6. Connected Car: Quantified Self becomes Quantified Car

    OpenAIRE

    Melanie Swan

    2015-01-01

    The automotive industry could be facing a situation of profound change and opportunity in the coming decades. There are a number of influencing factors such as increasing urban and aging populations, self-driving cars, 3D parts printing, energy innovation, and new models of transportation service delivery (Zipcar, Uber). The connected car means that vehicles are now part of the connected world, continuously Internet-connected, generating and transmitting data, which on the one hand can be hel...

  7. A Connection between Gravitation and Electromagnetism

    OpenAIRE

    Snyder, D. M.

    2000-01-01

    It is argued that there is a connection between the fundamental forces of electromagnetism and gravitation. This connection occurs because of: 1) the fundamental significance of the finite and invariant velocity of light in inertial reference frames in the special theory, and 2) the reliance of the general theory of relativity upon the special theory of relativity locally in spacetime. The connection between the fundamental forces of electromagnetism and gravitation follows immediately from t...

  8. Conformal transformation of tetrads and spin connection

    CERN Document Server

    Chakrabarty, Subhasish

    2016-01-01

    We investigate the conformal transformation of vierbein-Einstein-Palatini (VEP) action in terms of tetrads $e^I_\\mu$ and spin connection $A^{IJ}_\\mu$. The transformation of tetrads is obtained from that of the spacetime metric whereas that of the spin connection is not unique off-shell. When the connection can be completely expressed in terms of the tetrads, its transformation follows from that of the tetrads. We also construct the conformally invariant scalar field in the VEP formalism.

  9. Notes on sentential connections (predominantly) in Portuguese

    OpenAIRE

    Peres, João Andrade; Mascarenhas, Salvador

    2005-01-01

    In this article, we discuss a general typology of inter-sentential connections involving an explicit connective, including but no limited to subordination and coordination. In the first section, we briefly describe a proposal on the topic by one of the authors, which is taken as a point of departure. In the following section, we analyse step by step the diverse levels of organization of the connection system, ending in an overall picture and a suggestion of further additions related to hither...

  10. Conley: Computing connection matrices in Maple

    OpenAIRE

    Barakat, Mohamed; Robertz, Daniel

    2007-01-01

    In this work we announce the Maple package conley to compute connection and C-connection matrices. conley is based on our abstract homological algebra package homalg. We emphasize that the notion of braids is irrelevant for the definition and for the computation of such matrices. We introduce the notion of triangles that suffices to state the definition of (C)-connection matrices. The notion of octahedra, which is equivalent to that of braids is also introduced.

  11. Bluetooth LE (Low Energy) Connection Management

    OpenAIRE

    Khan, Olid Hossain

    2015-01-01

    This Bachelor’s thesis describes an Android Bluetooth Low Energy connection management collects sensor measurement data frequently and continuously from Bluetooth Low Energy devices to an Android phone. Currently there exists no such application that can connect with Bluetooth Low Energy devices continuously in a very short interval of time. Existing applications are also facing problems to establish a Bluetooth connection with Bluetooth Low Energy devices smoothly. The target of this res...

  12. The neural correlates of social connection

    OpenAIRE

    Hutcherson, Cendri A.; Seppala, Emma M.; James J Gross

    2015-01-01

    Cultivating social connection has long been a goal of psychology, philosophy, religion, and public policy. Yet the psychological and neural responses that accompany a feeling of connection to others remain unclear. In the present study, we used functional neuroimaging to shed light on the neural correlates of self- and other-focused processes during the successful self-generation of feelings of social connection. To do this, we used a trait judgment task to localize functional activation rela...

  13. Drill pipe threaded nipple connection design development

    Science.gov (United States)

    Saruev, A. L.; Saruev, L. A.; Vasenin, S. S.

    2015-11-01

    The paper presents the analysis of the behavior of the drill pipe nipple connection under the additional load generated by power pulses. The strain wave propagation through the nipple thread connection of drill pipes to the bottomhole is studied in this paper. The improved design of the nipple thread connection is suggested using the obtained experimental and theoretical data. The suggested connection design allows not only the efficient transmission of strain wave energy to a drill bit but also the automation of making-up and breaking-out drill pipes.

  14. On Metrizability of Invariant Affine Connections

    CERN Document Server

    Tanaka, Erico

    2011-01-01

    The metrizability problem for a symmetric affine connection on a manifold, invariant with respect to a group of diffeomorphisms G, is considered. We say that the connection is G-metrizable, if it is expressible as the Levi-Civita connection of a G-invariant metric field. In this paper we analyze the G-metrizability equations for the rotation group G = SO(3), acting canonically on three- and four-dimensional Euclidean spaces. We show that the property of the connection to be SO(3)-invariant allows us to find complete explicit description of all solutions of the SO(3)-metrizability equations.

  15. Affine connections, midpoint formation, and point reflection

    DEFF Research Database (Denmark)

    Kock, Anders

    2011-01-01

    We describe some differential-geometric structures in combinatorial terms: namely affine connections and their torsion and curvature, and we show that torsion free affine connections may equivalently be presented in terms of some simpler combinatorial structure: midpoint formation, and point refl...... reflection (geodesic symmetry). The method employed is that of synthetic differential geometry, which is briefly explained.......We describe some differential-geometric structures in combinatorial terms: namely affine connections and their torsion and curvature, and we show that torsion free affine connections may equivalently be presented in terms of some simpler combinatorial structure: midpoint formation, and point...

  16. Essential Connectivity Areas - CEHC, (Raster) [ds620

    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...

  17. Neighborhood connected perfect domination in graphs

    Directory of Open Access Journals (Sweden)

    Kulandai Vel M.P.

    2012-12-01

    Full Text Available Let $G = (V, E$ be a connected graph. A set $S$ of vertices in $G$ is a perfect dominating set if every vertex $v$ in $V-S$ is adjacent to exactly one vertex in $S$. A perfect dominating set $S$ is said to be a neighborhood connected perfect dominating set (ncpd-set if the induced subgraph $$ is connected. The minimum cardinality of a ncpd-set of $G$ is called the neighborhood connected perfect domination number of $G$ and is denoted by $\\gamma_{ncp}(G$. In this paper we initiate a study of this parameter.

  18. Connection Skeleton Extraction Based on Contour Connectedness

    Institute of Scientific and Technical Information of China (English)

    CHEN Mang; LIU Yun-cai

    2008-01-01

    A stable skeleton is very important to some applications such as vehicle navigation, object represent and pattern recognition. The connection skeleton is just one that not only can be computed stably but also can figure the connectivity structure of contour. A new method named continuous connectivity detection and a new model named approximate regular polygon (ARP) were proposed for connection skeleton extraction. Both the method and the model were tested by the real maps of road network including flyovers, interchanges and other common object contours. Satisfactory results were obtained.

  19. Further advances in deepwater flowline connection technology

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, J.R.; Cerqueira, M.B.; Silva, G.J.R.; Nagle, R.J.

    1996-12-31

    A diverless guidelineless flowline connection system, the so-called direct vertical connection, has been developed, and tested, which sharply decreases connection time, while allowing the lay-vessel itself to perform both flowline ends connections, thus dispensing with the use of auxiliary tools and making the operation more cost effective and reliable. This system has been designed to overcome problems associated with conventional pull-in systems, the lay-away method, ROV assisted pull-in systems and conventional vertical connections. The former have already been successfully used in Marlim field, in 25 wells located at water depths ranging from 740 m to 980 m. The direct vertical connection can now be considered a field proven method. Five import flowline connections have already been successfully performed in Albacora field manifold, installed at 620 m water depth. From now on, based on the excellent results achieved from those installations and previous tests, all deepwater Brazilian subsea trees and manifolds will be designed for direct vertical connection. Sixty six trees and six manifolds incorporating the direct vertical connection system are presently under fabrication in Brazil.

  20. The solar-coffee connection

    Energy Technology Data Exchange (ETDEWEB)

    Wright, G.

    2000-04-01

    Coffee connoisseurs, when they quaff a cup of coffee or enjoy a jug of joe, don't generally consider the costs to the environment of their favorite beverage. But the fact is that traditional coffee production is hard on the environment, exacting a toll on the native forests and waterways of Central America and on the migratory birds of the western hemisphere. Coffee growing is the second greatest cause of rainforest destruction after cattle ranching, because a lot of trees are cut down to dry the freshly-picked coffee crop. But espresso-sipping environmentalists and an eco-conscious Joe Public can take comfort in a promising new connection between solar energy and rainforest-friendly coffee--solar-dried coffee. And they can take pleasure in it too, because solar-dried coffee, according to virtually everyone who tries it, is the best-tasting coffee made. Considering that coffee is the second most-traded commodity next to oil, and the second most popular beverage in the world next to water, consumed by billions of people, any new process that reduces the environmental damage occasioned by coffee-growing and processing is significant.

  1. QED on the connection machine

    International Nuclear Information System (INIS)

    Physicists believe that the world is described in terms of gauge theories. A popular technique for investigating these theories is to discretize them onto a lattice and simulate numerically by a computer, yielding so-called lattice gauge theory. Such computations require at least 1014 floating-point operations, necessitating the use of advanced architecture supercomputers such as the Connection Machine. Currently the most important gauge theory to be solved is that describing the sub-nuclear world of high energy physics: quantum chromo-dynamics (QCD). The simplest example of a gauge theory is Quantum electro-dynamics (QED), the theory which describes the interaction of electrons and photons. Simulation of QCD requires computer software very similar to that for the simpler QED problem. The authors' current QED code achieves a computational rate of 1.6 million lattice site updates per second for a Monte Carlo algorithm, and 7.4 million site updates per second for a microcanonical algorithm. The estimate performance for a Monte Carlo QCD code is 200,000 site updates per second (or 5.6 Gflops/sec)

  2. IMPROVED NETWORK CONNECTIVITY IN MANETS

    Directory of Open Access Journals (Sweden)

    B R Sujatha

    2009-10-01

    Full Text Available The growth in wireless communication technologies has resulted in a considerable amount ofattention given to mobile adhoc networks. All mobile hosts in an adhoc network are embedded withpacket forwarding capabilities. It is decentralized and is independent of infrastructure. Since mobilehosts in an adhoc network usually move freely, the topology of the network changes dynamically anddisconnection occurs frequently. These characteristics require the routing protocols to find analternative path towards the destination for data transfer. The existing on-demand routing protocolsdoes the alternative path establishment only after the disconnection of links in the existing path. Thedata sent by the source during alternate path establishment period will be lost leading to incompletedata transfer. The network traffic will therefore increase considerably. This problem can be overcomeby establishing an alternative path when the existing path is more likely to be broken, by sending awarning message to the source indicating the likelihood of disconnection. In this paper an attempt hasbeen made to analyze a protocol that improves the network connectivity by preempting the alternativepath before the existing link gets failed by monitoring the signal strength and ‘age of the path’.

  3. Cortical attractor network dynamics with diluted connectivity.

    Science.gov (United States)

    Rolls, Edmund T; Webb, Tristan J

    2012-01-24

    The connectivity of the cerebral cortex is diluted, with the probability of excitatory connections between even nearby pyramidal cells rarely more than 0.1, and in the hippocampus 0.04. To investigate the extent to which this diluted connectivity affects the dynamics of attractor networks in the cerebral cortex, we simulated an integrate-and-fire attractor network taking decisions between competing inputs with diluted connectivity of 0.25 or 0.1, and with the same number of synaptic connections per neuron for the recurrent collateral synapses within an attractor population as for full connectivity. The results indicated that there was less spiking-related noise with the diluted connectivity in that the stability of the network when in the spontaneous state of firing increased, and the accuracy of the correct decisions increased. The decision times were a little slower with diluted than with complete connectivity. Given that the capacity of the network is set by the number of recurrent collateral synaptic connections per neuron, on which there is a biological limit, the findings indicate that the stability of cortical networks, and the accuracy of their correct decisions or memory recall operations, can be increased by utilizing diluted connectivity and correspondingly increasing the number of neurons in the network, with little impact on the speed of processing of the cortex. Thus diluted connectivity can decrease cortical spiking-related noise. In addition, we show that the Fano factor for the trial-to-trial variability of the neuronal firing decreases from the spontaneous firing state value when the attractor network makes a decision. This article is part of a Special Issue entitled "Neural Coding". PMID:21875702

  4. Super Connectivity of Line Graphs and Digraphs

    Institute of Scientific and Technical Information of China (English)

    Min Lü; Jun-Ming Xu

    2006-01-01

    The h-super connectivity κh and the h-super edge-connectivity λh are more refined network reliability indices than the connectivity and the edge-connectivity. This paper shows that for a connected balanced digraph D and its line digraph L, if D is optimally super edge-connected, then κ1(L) = 2λ1(D), and that for a connected graph G and its line graph L, if one of κ1(L) and λ2(G) exists, then κ1(L) = λ2(G). This paper determines that κ1 (B(d, n)) is equal to 4d - 8 for n = 2 and d ≥ 4, and to 4d - 4 for n ≥ 3 and d ≥ 3, and that κ1(K(d,n)) is equal to 4d- 4 for d ≥ 2 and n ≥ 2 except K(2,2). It then follows that B(d,n) and K(d,n) are both super connected for any d ≥ 2 and n ≥ 1.

  5. Quick-Connect Heavy-Duty Fastener

    Science.gov (United States)

    Moore, D. M.

    1986-01-01

    Attaching device combines fast connection and disconnection with high strength. T-shaped stud engages groove in receptacle after one-quarter turn. Further turning tightens nut on receptacle. Like quarter-turn attaching devices, connected and disconnected quickly. Like threaded devices, adjusted to desired preload, withstand high loads, and accommodate wide range of grip lengths.

  6. Connect the Book. George Washington's Teeth

    Science.gov (United States)

    Brodie, Carolyn S.

    2005-01-01

    February celebrates both National Children's Dental Health Month and President's Day (February 21), so this month's "Connect the Book" column features a book with connections to both events. George Washington, the first President of the United States (1789-1797) and known as the "Father of Our Country," had a serious dental health problem that…

  7. Supervision, Staff Development, and Evaluation Connections.

    Science.gov (United States)

    McQuarrie, Frank O.; Wood, Fred H.

    1991-01-01

    Examines the relationship between supervision, staff development, and teacher evaluation, discussing why educators must strive to make connections among the three, identifying important misunderstandings about them, and describing the purposes of each process and the similarities, differences, and connections between them. Together, they can be…

  8. Strong Connections and Invertible Weak Entwining Structures

    Institute of Scientific and Technical Information of China (English)

    J.N.ALONSO (A)LVAREZ; J.M.FERN(A)NDEZ VILABOA; R.GONZ(A)LEZ RODR(I)GUEZ

    2012-01-01

    In this paper we obtain a criterion under which the bijectivity of the canonical morphism of a weak Galois extension associated to a weak invertible entwining structure is equivalent to the existence of a strong connection form.Also we obtain an explicit formula for a strong connection under equivariant projective conditions or under coseparability conditions.

  9. A Random Walk: Stumbling across Connections

    Science.gov (United States)

    Wasserman, Nicholas H.

    2015-01-01

    Finding and designing tasks that allow for students to make connections among mathematical ideas is important for mathematics educators. One such task, which affords students the opportunity to make connections and engage with significant mathematical ideas through a variety of problem-solving approaches, is described in this article. Three…

  10. Connecting Functions in Geometry and Algebra

    Science.gov (United States)

    Steketee, Scott; Scher, Daniel

    2016-01-01

    One goal of a mathematics education is that students make significant connections among different branches of mathematics. Connections--such as those between arithmetic and algebra, between two-dimensional and three-dimensional geometry, between compass-and-straight-edge constructions and transformations, and between calculus and analytic…

  11. Physical Science Connected Classrooms: Case Studies

    Science.gov (United States)

    Irving, Karen; Sanalan, Vehbi; Shirley, Melissa

    2009-01-01

    Case-study descriptions of secondary and middle school classrooms in diverse contexts provide examples of how teachers implement connected classroom technology to facilitate formative assessment in science instruction. Connected classroom technology refers to a networked system of handheld devices designed for classroom use. Teachers were…

  12. Water Treatment Technology - Cross-Connections.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on cross connections provides instructional materials for two competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on cross connections terminology and control devices. For each…

  13. Are we connected? : Ports in Global Networks

    NARCIS (Netherlands)

    R.A. Zuidwijk (Rob)

    2015-01-01

    markdownabstractAbstract Global supply chains are built on organizational, information, and logistics networks. Ports are connected via these networks and also need to connect these networks. Synchromodality is an innovative concept for container transportation, and the port plays an important ro

  14. Connecting Representations: Using Predict, Check, Explain

    Science.gov (United States)

    Roy, George J.; Fueyo, Vivian; Vahey, Philip; Knudsen, Jennifer; Rafanan, Ken; Lara-Meloy, Teresa

    2016-01-01

    Although educators agree that making connections with the real world, as advocated by "Principles to Actions: Ensuring Mathematical Success for All" (NCTM 2014), is important, making such connections while addressing important mathematics is elusive. The authors have found that math content coupled with the instructional strategy of…

  15. Making Connections between Research and Practice

    Science.gov (United States)

    Porter, Andrew; McMaken, Jennifer

    2009-01-01

    Strengthening connections between research and practice is an important goal in education. Making the connection has both a supply side and a demand side but the demand is often ignored in education. The authors offer six hypotheses about why this situation occurs.

  16. MedlinePlus Connect: Web Application

    Science.gov (United States)

    ... in English or Spanish. MedlinePlus Connect will assume English is the language if it is not specified. If you wish ... in English or Spanish. MedlinePlus Connect will assume English is the language if it is not specified. If you wish ...

  17. Natural Connections on Riemannian Product Manifolds

    CERN Document Server

    Gribacheva, Dobrinka

    2011-01-01

    A Riemannian almost product manifold with integrable almost product structure is called a Riemannian product manifold. In the present paper the natural connections on such manifolds are studied, i.e. the linear connections preserving the almost product structure and the Riemannian metric.

  18. Making the Chromosome-Gene-Protein Connection.

    Science.gov (United States)

    Mulvihill, Charlotte

    1996-01-01

    Presents an exercise that demonstrates the chromosome-gene-protein connection using sickle-cell anemia, a genetic disease with a well-characterized molecular basis. Involves connecting changes in DNA to protein outcomes and tying them into the next generation by meiosis and gamete formation with genetic crosses. Motivates students to integrate…

  19. The Matrix Connection: Fibonacci and Inductive Proof

    Science.gov (United States)

    Veenstra, Tamara B.; Miller, Catherine M.

    2006-01-01

    This article presents several activities (some involving graphing calculators) designed to guide students to discover several interesting properties of Fibonacci numbers. Then, we explore interesting connections between Fibonacci numbers and matrices; using this connection and induction we prove divisibility properties of Fibonacci numbers.

  20. Directional connectivity in hydrology and ecology.

    Science.gov (United States)

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

    2012-12-01

    Quantifying hydrologic and ecological connectivity has contributed to understanding transport and dispersal processes and assessing ecosystem degradation or restoration potential. However, there has been little synthesis across disciplines. The growing field of ecohydrology and recent recognition that loss of hydrologic connectivity is leading to a global decline in biodiversity underscore the need for a unified connectivity concept. One outstanding need is a way to quantify directional connectivity that is consistent, robust to variations in sampling, and transferable across scales or environmental settings. Understanding connectivity in a particular direction (e.g., streamwise, along or across gradient, between sources and sinks, along cardinal directions) provides critical information for predicting contaminant transport, planning conservation corridor design, and understanding how landscapes or hydroscapes respond to directional forces like wind or water flow. Here we synthesize progress on quantifying connectivity and develop a new strategy for evaluating directional connectivity that benefits from use of graph theory in ecology and percolation theory in hydrology. The directional connectivity index (DCI) is a graph-theory based, multiscale metric that is generalizable to a range of different structural and functional connectivity applications. It exhibits minimal sensitivity to image rotation or resolution within a given range and responds intuitively to progressive, unidirectional change. Further, it is linearly related to the integral connectivity scale length--a metric common in hydrology that correlates well with actual fluxes--but is less computationally challenging and more readily comparable across different landscapes. Connectivity-orientation curves (i.e., directional connectivity computed over a range of headings) provide a quantitative, information-dense representation of environmental structure that can be used for comparison or detection of

  1. Directional connectivity in hydrology and ecology

    Science.gov (United States)

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

    2012-01-01

    Quantifying hydrologic and ecological connectivity has contributed to understanding transport and dispersal processes and assessing ecosystem degradation or restoration potential. However, there has been little synthesis across disciplines. The growing field of ecohydrology and recent recognition that loss of hydrologic connectivity is leading to a global decline in biodiversity underscore the need for a unified connectivity concept. One outstanding need is a way to quantify directional connectivity that is consistent, robust to variations in sampling, and transferable across scales or environmental settings. Understanding connectivity in a particular direction (e.g., streamwise, along or across gradient, between sources and sinks, along cardinal directions) provides critical information for predicting contaminant transport, planning conservation corridor design, and understanding how landscapes or hydroscapes respond to directional forces like wind or water flow. Here we synthesize progress on quantifying connectivity and develop a new strategy for evaluating directional connectivity that benefits from use of graph theory in ecology and percolation theory in hydrology. The directional connectivity index (DCI) is a graph-theory based, multiscale metric that is generalizable to a range of different structural and functional connectivity applications. It exhibits minimal sensitivity to image rotation or resolution within a given range and responds intuitively to progressive, unidirectional change. Further, it is linearly related to the integral connectivity scale length—a metric common in hydrology that correlates well with actual fluxes—but is less computationally challenging and more readily comparable across different landscapes. Connectivity-orientation curves (i.e., directional connectivity computed over a range of headings) provide a quantitative, information-dense representation of environmental structure that can be used for comparison or detection of

  2. Algebraic connectivity of connected graphs with fixed number of pendant vertices

    CERN Document Server

    Lal, Arbind K; Sahoo, Binod K

    2010-01-01

    In this paper we consider the following problem: Over the class of all simple connected graphs of order $n$ with $k$ pendant vertices ($n,k$ being fixed), which graph maximizes (respectively, minimizes) the algebraic connectivity? We also discuss the algebraic connectivity of unicyclic graphs.

  3. 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

  4. Connectiveness and civility in online learning.

    Science.gov (United States)

    Rieck, Susan; Crouch, Laura

    2007-11-01

    As the classroom shifts from teacher-centered to learner-centered and from face-to-face to online, nursing faculty members are challenged to promote a sense of connectiveness and social interaction. Making connectiveness more elusive is the perception of rude, impolite, or unkind communication. The purpose of this descriptive-exploratory study was to examine perceptions of connectiveness and civility in online nursing courses. Ninety-six students in four nursing programs participated in the study. Strategies that promote connectiveness with peers are in-person activities whenever possible and discussion assignments that include social activities. Timely feedback when responding to questions and prompt grading are important for student-to-instructor connectiveness. Thirty-five percent of the students encountered rude or unkind communication with peers, and 60% reported incivility from instructors. Their suggestions for effective handling of rude communication included addressing the behavior privately, giving guidance about netiquette, and defining what constitutes rude behavior. PMID:17765016

  5. Spin connection and renormalization of teleparallel action

    Energy Technology Data Exchange (ETDEWEB)

    Krssak, Martin; Pereira, J.G. [Universidade Estadual Paulista, Instituto de Fisica Teorica, Sao Paulo, SP (Brazil)

    2015-11-15

    In general relativity, inertia and gravitation are both included in the Levi-Civita connection. As a consequence, the gravitational action, as well as the corresponding energy-momentum density, are in general contaminated by spurious contributions coming from inertial effects. In teleparallel gravity, on the other hand, because the spin connection represents inertial effects only, it is possible to separate inertia from gravitation. Relying on this property, it is shown that to each tetrad there is naturally associated a spin connection that locally removes the inertial effects from the action. The use of the appropriate spin connection can be viewed as a renormalization process in the sense that the computation of energy and momentum naturally yields the physically relevant values. A self-consistent method for solving field equations and determining the appropriate spin connection is presented. (orig.)

  6. Spin connection and renormalization of teleparallel action

    Energy Technology Data Exchange (ETDEWEB)

    Krššák, Martin, E-mail: krssak@ift.unesp.br; Pereira, J. G., E-mail: jpereira@ift.unesp.br [Instituto de Física Teórica, Universidade Estadual Paulista, R. Dr. Bento Teobaldo Ferraz 271, 01140-070, São Paulo, SP (Brazil)

    2015-10-31

    In general relativity, inertia and gravitation are both included in the Levi–Civita connection. As a consequence, the gravitational action, as well as the corresponding energy–momentum density, are in general contaminated by spurious contributions coming from inertial effects. In teleparallel gravity, on the other hand, because the spin connection represents inertial effects only, it is possible to separate inertia from gravitation. Relying on this property, it is shown that to each tetrad there is naturally associated a spin connection that locally removes the inertial effects from the action. The use of the appropriate spin connection can be viewed as a renormalization process in the sense that the computation of energy and momentum naturally yields the physically relevant values. A self-consistent method for solving field equations and determining the appropriate spin connection is presented.

  7. Connecting network properties of rapidly disseminating epizoonotics.

    Directory of Open Access Journals (Sweden)

    Ariel L Rivas

    Full Text Available To effectively control the geographical dissemination of infectious diseases, their properties need to be determined. To test that rapid microbial dispersal requires not only susceptible hosts but also a pre-existing, connecting network, we explored constructs meant to reveal the network properties associated with disease spread, which included the road structure.Using geo-temporal data collected from epizoonotics in which all hosts were susceptible (mammals infected by Foot-and-mouth disease virus, Uruguay, 2001; birds infected by Avian Influenza virus H5N1, Nigeria, 2006, two models were compared: 1 'connectivity', a model that integrated bio-physical concepts (the agent's transmission cycle, road topology into indicators designed to measure networks ('nodes' or infected sites with short- and long-range links, and 2 'contacts', which focused on infected individuals but did not assess connectivity.THE CONNECTIVITY MODEL SHOWED FIVE NETWORK PROPERTIES: 1 spatial aggregation of cases (disease clusters, 2 links among similar 'nodes' (assortativity, 3 simultaneous activation of similar nodes (synchronicity, 4 disease flows moving from highly to poorly connected nodes (directionality, and 5 a few nodes accounting for most cases (a "20:80" pattern. In both epizoonotics, 1 not all primary cases were connected but at least one primary case was connected, 2 highly connected, small areas (nodes accounted for most cases, 3 several classes of nodes were distinguished, and 4 the contact model, which assumed all primary cases were identical, captured half the number of cases identified by the connectivity model. When assessed together, the synchronicity and directionality properties explained when and where an infectious disease spreads.Geo-temporal constructs of Network Theory's nodes and links were retrospectively validated in rapidly disseminating infectious diseases. They distinguished classes of cases, nodes, and networks, generating information usable

  8. Road Weather and Connected Vehicles

    Science.gov (United States)

    Pisano, P.; Boyce, B. C.

    2015-12-01

    On average, there are over 5.8 M vehicle crashes each year of which 23% are weather-related. Weather-related crashes are defined as those crashes that occur in adverse weather or on slick pavement. The vast majority of weather-related crashes happen on wet pavement (74%) and during rainfall (46%). Connected vehicle technologies hold the promise to transform road-weather management by providing improved road weather data in real time with greater temporal and geographic accuracy. This will dramatically expand the amount of data that can be used to assess, forecast, and address the impacts that weather has on roads, vehicles, and travelers. The use of vehicle-based measurements of the road and surrounding atmosphere with other, more traditional weather data sources, and create road and atmospheric hazard products for a variety of users. The broad availability of road weather data from mobile sources will vastly improve the ability to detect and forecast weather and road conditions, and will provide the capability to manage road-weather response on specific roadway links. The RWMP is currently demonstrating how weather, road conditions, and related vehicle data can be used for decision making through an innovative Integrated Mobile Observations project. FHWA is partnering with 3 DOTs (MN, MI, & NV) to pilot these applications. One is a mobile alerts application called the Motorists Advisories and Warnings (MAW) and a maintenance decision support application. These applications blend traditional weather information (e.g., radar, surface stations) with mobile vehicle data (e.g., temperature, brake status, wiper status) to determine current weather conditions. These weather conditions, and other road-travel-relevant information, are provided to users via web and phone applications. The MAW provides nowcasts and short-term forecasts out to 24 hours while the EMDSS application can provide forecasts up to 72 hours in advance. The three DOTs have placed readers and external

  9. Detecting Functional Connectivity During Audiovisual Integration with MEG: A Comparison of Connectivity Metrics.

    Science.gov (United States)

    Ard, Tyler; Carver, Frederick W; Holroyd, Tom; Horwitz, Barry; Coppola, Richard

    2015-08-01

    In typical magnetoencephalography and/or electroencephalography functional connectivity analysis, researchers select one of several methods that measure a relationship between regions to determine connectivity, such as coherence, power correlations, and others. However, it is largely unknown if some are more suited than others for various types of investigations. In this study, the authors investigate seven connectivity metrics to evaluate which, if any, are sensitive to audiovisual integration by contrasting connectivity when tracking an audiovisual object versus connectivity when tracking a visual object uncorrelated with the auditory stimulus. The authors are able to assess the metrics' performances at detecting audiovisual integration by investigating connectivity between auditory and visual areas. Critically, the authors perform their investigation on a whole-cortex all-to-all mapping, avoiding confounds introduced in seed selection. The authors find that amplitude-based connectivity measures in the beta band detect strong connections between visual and auditory areas during audiovisual integration, specifically between V4/V5 and auditory cortices in the right hemisphere. Conversely, phase-based connectivity measures in the beta band as well as phase and power measures in alpha, gamma, and theta do not show connectivity between audiovisual areas. The authors postulate that while beta power correlations detect audiovisual integration in the current experimental context, it may not always be the best measure to detect connectivity. Instead, it is likely that the brain utilizes a variety of mechanisms in neuronal communication that may produce differential types of temporal relationships.

  10. Resting state functional connectivity in perfusion imaging: correlation maps with BOLD connectivity and resting state perfusion.

    Directory of Open Access Journals (Sweden)

    Roberto Viviani

    Full Text Available Functional connectivity is a property of the resting state that may provide biomarkers of brain function and individual differences. Classically, connectivity is estimated as the temporal correlation of spontaneous fluctuations of BOLD signal. We investigated differences in connectivity estimated from the BOLD and CBF signal present in volumes acquired with arterial spin labeling technique in a large sample (N = 265 of healthy individuals. Positive connectivity was observable in both BOLD and CBF signal, and was present in the CBF signal also at frequencies lower than 0.009 Hz, here investigated for the first time. Negative connectivity was more variable. The validity of positive connectivity was confirmed by the existence of correlation across individuals in its intensity estimated from the BOLD and CBF signal. In contrast, there was little or no correlation across individuals between intensity of connectivity and mean perfusion levels, suggesting that these two biomarkers correspond to distinct sources of individual differences.

  11. Mapping hydrologic connectivity of geographically isolated wetlands

    Science.gov (United States)

    Ameli, Ali; Creed, Irena

    2016-04-01

    Geographically isolated wetlands (GIWs) are characterized as depressional landscape features completely surrounded by uplands. These small and typically circular landscape features represent a vast majority of wetlands in various landscapes in North America (98% of all wetlands in the Prairie Pothole Region). Geographical isolation, however, does not imply the hydrological isolation. Although geospatial data (e.g., aerial photos) suggested that GIWs lack a persistent surface water connection, the groundwater connection between GIWs and navigable downstream waters can be substantial with large fluxes at the regional scales. The surface/subsurface connections among GIWs and between GIWs and navigable waters are difficult to map and quantify. This is intimately tied to the fact that an efficient incorporation of these small geometric features and characterization of the mechanisms behind these connectivities are challenging within grid-based simulators. We used a physically-based grid-free groundwater-surface water interaction and surface flow routing schemes to map and assess the watershed-scale GIWs connectivity within an extensively studied watershed at the Canadian prairie pothole region with high density of GIWs. The results showed that there is a persistent subsurface connectivity among GIWs and between GIWs and navigable waters. Surface connection was rare and only occurred during extreme events. The results of this paper have significant implications for developing scientifically grounded environmental policy for protection of GIWs within North American Prairie.

  12. Altered thalamic functional connectivity in multiple sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yaou; Liang, Peipeng; Duan, Yunyun; Huang, Jing; Ren, Zhuoqiong; Jia, Xiuqin [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong, Huiqing; Ye, Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Shi, Fu-Dong [Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052 (China); Butzkueven, Helmut [Department of Medicine, University of Melbourne, Parkville 3010 (Australia); Li, Kuncheng, E-mail: kunchengli55@gmail.com [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

    2015-04-15

    Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

  13. Low pore connectivity in natural rock

    Science.gov (United States)

    Hu, Qinhong; Ewing, Robert P.; Dultz, Stefan

    2012-05-01

    As repositories for CO2 and radioactive waste, as oil and gas reservoirs, and as contaminated sites needing remediation, rock formations play a central role in energy and environmental management. The connectivity of the rock's porespace strongly affects fluid flow and solute transport. This work examines pore connectivity and its implications for fluid flow and chemical transport. Three experimental approaches (imbibition, tracer concentration profiles, and imaging) were used in combination with network modeling. In the imbibition results, three types of imbibition slope [log (cumulative imbibition) vs. log (imbibition time)] were found: the classical 0.5, plus 0.26, and 0.26 transitioning to 0.5. The imbibition slope of 0.26 seen in Indiana sandstone, metagraywacke, and Barnett shale indicates low pore connectivity, in contrast to the slope of 0.5 seen in the well-connected Berea sandstone. In the tracer profile work, rocks exhibited different distances to the plateau porosity, consistent with the pore connectivity from the imbibition tests. Injection of a molten metal into connected pore spaces, followed by 2-D imaging of the solidified alloy in polished thin sections, allowed direct assessment of pore structure and lateral connection in the rock samples. Pore-scale network modeling gave results consistent with measurements, confirming pore connectivity as the underlying cause of both anomalous behaviors: imbibition slope not having the classical value of 0.5, and accessible porosity being a function of distance from the edge. A poorly connected porespace will exhibit anomalous behavior in fluid flow and chemical transport, such as a lower imbibition slope (in air-water system) and diffusion rate than expected from classical behavior.

  14. Low Pore Connectivity in Natural Rock

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Qinhong; Ewing, Robert P.; Dultz, Stefan

    2012-05-15

    As repositories for CO₂ and radioactive waste, as oil and gas reservoirs, and as contaminated sites needing remediation, rock formations play a central role in energy and environmental management. The connectivity of the rock's porespace strongly affects fluid flow and solute transport. This work examines pore connectivity and its implications for fluid flow and chemical transport. Three experimental approaches (imbibition, tracer concentration profiles, and imaging) were used in combination with network modeling. In the imbibition results, three types of imbibition slope [log (cumulative imbibition) vs. log (imbibition time)] were found: the classical 0.5, plus 0.26, and 0.26 transitioning to 0.5. The imbibition slope of 0.26 seen in Indiana sandstone, metagraywacke, and Barnett shale indicates low pore connectivity, in contrast to the slope of 0.5 seen in the well-connected Berea sandstone. In the tracer profile work, rocks exhibited different distances to the plateau porosity, consistent with the pore connectivity from the imbibition tests. Injection of a molten metal into connected pore spaces, followed by 2-D imaging of the solidified alloy in polished thin sections, allowed direct assessment of pore structure and lateral connection in the rock samples. Pore-scale network modeling gave results consistent with measurements, confirming pore connectivity as the underlying cause of both anomalous behaviors: imbibition slope not having the classical value of 0.5, and accessible porosity being a function of distance from the edge. A poorly connected porespace will exhibit anomalous behavior in fluid flow and chemical transport, such as a lower imbibition slope (in air–water system) and diffusion rate than expected from classical behavior.

  15. Low pore connectivity in natural rock.

    Science.gov (United States)

    Hu, Qinhong; Ewing, Robert P; Dultz, Stefan

    2012-05-15

    As repositories for CO(2) and radioactive waste, as oil and gas reservoirs, and as contaminated sites needing remediation, rock formations play a central role in energy and environmental management. The connectivity of the rock's porespace strongly affects fluid flow and solute transport. This work examines pore connectivity and its implications for fluid flow and chemical transport. Three experimental approaches (imbibition, tracer concentration profiles, and imaging) were used in combination with network modeling. In the imbibition results, three types of imbibition slope [log (cumulative imbibition) vs. log (imbibition time)] were found: the classical 0.5, plus 0.26, and 0.26 transitioning to 0.5. The imbibition slope of 0.26 seen in Indiana sandstone, metagraywacke, and Barnett shale indicates low pore connectivity, in contrast to the slope of 0.5 seen in the well-connected Berea sandstone. In the tracer profile work, rocks exhibited different distances to the plateau porosity, consistent with the pore connectivity from the imbibition tests. Injection of a molten metal into connected pore spaces, followed by 2-D imaging of the solidified alloy in polished thin sections, allowed direct assessment of pore structure and lateral connection in the rock samples. Pore-scale network modeling gave results consistent with measurements, confirming pore connectivity as the underlying cause of both anomalous behaviors: imbibition slope not having the classical value of 0.5, and accessible porosity being a function of distance from the edge. A poorly connected porespace will exhibit anomalous behavior in fluid flow and chemical transport, such as a lower imbibition slope (in air-water system) and diffusion rate than expected from classical behavior.

  16. Bridge connection of quantum Hall elementary devices

    CERN Document Server

    Callegaro, Luca

    2013-01-01

    Multiple-series and multiple-parallel connections of quantum Hall elementary devices allow the realization of multiple or fractional values of the quantized Hall resistance, rejecting the effect of contact and wiring resistances. We introduce here the multiple-bridge connection, which maintains the properties of multiple-series and parallel connections and allows more freedom in the choice of the topology of networks composed of quantum Hall elements, and the design of more efficient quantum Hall array resistance standards (and other devices). As an example, a 5-element network is analyzed in detail.

  17. Failure Analysis of A Fractured Connecting Rod

    OpenAIRE

    Mohammed, M. N.; Omar, M. Z.; Zainuddin Sajuri; A. Salah; M.A. Abdelgnei; Salleh, M. S.

    2012-01-01

    In many cases, the major reason behind or causing catastrophic engine failure is the occurrence of the connecting-rod failure and sometimes, such a failure can be attributed to the broken connecting rod’s shank especially when there is a probability of being pushed through the side of the crank-case, thereby making the engine irreparable. Thus, the major aim of the current work is to analyze the connecting rod failure. The study applied a finite element analysis and metallographic examination...

  18. Intermittently connected mobile ad hoc networks

    CERN Document Server

    Jamalipour, Abbas

    2011-01-01

    In the last few years, there has been extensive research activity in the emerging area of Intermittently Connected Mobile Ad Hoc Networks (ICMANs). By considering the nature of intermittent connectivity in most real word mobile environments without any restrictions placed on users' behavior, ICMANs are eventually formed without any assumption with regard to the existence of a end-to-end path between two nodes wishing to communicate. It is different from the conventional Mobile Ad Hoc Networks (MANETs), which have been implicitly viewed as a connected graph with established complete paths betwe

  19. The Twisted-Cube Connected Networks

    Institute of Scientific and Technical Information of China (English)

    WANG Deqiang; ZHAO Lianchang

    1999-01-01

    This paper presents a newinterconnection network topology, called the twisted-cube connectednetwork, which is a generation of the twisted 3-cube. The twisted-cubeconnected network is a variant of the hypercube, and it has a betterrecursive structure. The regularity, connectivities, subgraphs of thetwisted-cube connected network are studied. The twisted-cube connectednetwork is proved to be a 3-cube-free network, which is the essentialdifference from the hypercube and variants of the hypercube. Anefficient routing algorithm is proposed, and the diameter ofn-dimensional twisted-cube connected network is proved to be just[n+1/2] which is less than that of the hypercube.

  20. Electrical connection structure for a superconductor element

    Science.gov (United States)

    Lallouet, Nicolas; Maguire, James

    2010-05-04

    The invention relates to an electrical connection structure for a superconductor element cooled by a cryogenic fluid and connected to an electrical bushing, which bushing passes successively through an enclosure at an intermediate temperature between ambient temperature and the temperature of the cryogenic fluid, and an enclosure at ambient temperature, said bushing projecting outside the ambient temperature enclosure. According to the invention, said intermediate enclosure is filled at least in part with a solid material of low thermal conductivity, such as a polyurethane foam or a cellular glass foam. The invention is applicable to connecting a superconductor cable at cryogenic temperature to a device for equipment at ambient temperature.

  1. Is the spin connection confined or condensed?

    CERN Document Server

    Donoghue, John F

    2016-01-01

    The spin connection enters the theory of gravity as a nonabelian gauge field associated with local Lorentz transformations. Normally it is eliminated from making an extra assumption - that of the metricity of the vierbein field. However, treated by itself with the usual gauge action, it has a negative beta function, implying that it is asymptotically free. I suggest that the spin connection could be confined (or perhaps partially confined) in the same way as other nonabelian gauge fields. This would remove the need to make the extra assumption of metricity, as the spin connection would not be present in the low energy theory, leaving the symmetry to be realized only using metric variables.

  2. Characterization of pars intermedia connections in amphibians by biocytin tract tracing and immunofluorescence aided by confocal microscopy

    NARCIS (Netherlands)

    Jansen, K; Fabro, C; Artero, C; Feuilloley, M; Vaudry, H; Fasolo, A; Franzoni, MF

    1997-01-01

    Biocytin, recently introduced in neuroanatomical studies, was used as a retrograde tract tracer in combination with immunofluorescence in order to analyse the neurochemical characters of some central neuronal projections to the pars intermedia in two amphibian species, the anuran Rana esculenta and

  3. PROCESS OF ELECTRICAL CONNECTION OF PHOTOVOLTAIC DEVICES

    DEFF Research Database (Denmark)

    2012-01-01

    A photovoltaic cell module comprising at least two serially connected photovoltaic cells on a common substrate, wherein the cells each comprise a first electrode layer, a first charge selective layer, a light harvesting layer which comprises an organic conjugated polymer, and a second charge...... of the pair, which connection is made through the light harvesting layer common to the at least one pair of cells, without forming an electrical connection with the first electrode of the first cell or the second charge selective layer of the second cell; and a method of making such a photovoltaic cell module....... selective layer that selects for an opposite charge to the first charge selective layer, wherein the first electrode layers for each cell are formed such that the first electrode layer of one cell has no direct electrical connection to the first electrode layer of any other cell, and the second charge...

  4. Heteroclinic connections in plane Couette flow

    CERN Document Server

    Halcrow, Jonathan; Cvitanović, Predrag; Viswanath, Divakar

    2008-01-01

    Plane Couette flow transitions to turbulence for Re~325 even though the laminar solution with a linear profile is linearly stable for all Re (Reynolds number). One starting point for understanding this subcritical transition is the existence of invariant sets in the state space of the Navier Stokes equation, such as upper and lower branch equilibria and periodic and relative periodic solutions, that are quite distinct from the laminar solution. This article reports several heteroclinic connections between such objects and briefly describes a numerical method for locating heteroclinic connections. Computing such connections is essential for understanding the global dynamics of spatially localized structures that occur in transitional plane Couette flow. We show that the nature of streaks and streamwise rolls can change significantly along a heteroclinic connection.

  5. 47 CFR 54.506 - Internal connections.

    Science.gov (United States)

    2010-10-01

    ... library receives internal connections services other than basic maintenance services that are shared with other schools or libraries (for example, as part of a consortium), the shared services will be... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED)...

  6. Affine connection form of Regge calculus

    CERN Document Server

    Khatsymovsky, V M

    2015-01-01

    Regge action is represented analogously to how the Palatini action for general relativity (GR) as some functional of the metric and a general connection as independent variables represents the Einstein-Hilbert action. The piecewise flat (or simplicial) spacetime of Regge calculus is equipped with some world coordinates and some piecewise affine metric which is completely defined by the set of edge lengths and the world coordinates of the vertices. The conjugate variables are the general nondegenerate matrices on the 3-simplices which play a role of a general discrete connection. Our previous result on some representation of the Regge calculus action in terms of the local Euclidean (Minkowsky) frame vectors and orthogonal connection matrices as independent variables is somewhat modified for the considered case of the general linear group GL(4,R) of the connection matrices. As a result, we have some action invariant w. r. t. arbitrary change of coordinates of the vertices (and related GL(4,R) transformations in...

  7. Partial connectivity increases cultural accumulation within groups.

    Science.gov (United States)

    Derex, Maxime; Boyd, Robert

    2016-03-15

    Complex technologies used in most human societies are beyond the inventive capacities of individuals. Instead, they result from a cumulative process in which innovations are gradually added to existing cultural traits across many generations. Recent work suggests that a population's ability to develop complex technologies is positively affected by its size and connectedness. Here, we present a simple computer-based experiment that compares the accumulation of innovations by fully and partially connected groups of the same size in a complex fitness landscape. We find that the propensity to learn from successful individuals drastically reduces cultural diversity within fully connected groups. In comparison, partially connected groups produce more diverse solutions, and this diversity allows them to develop complex solutions that are never produced in fully connected groups. These results suggest that explanations of ancestral patterns of cultural complexity may need to consider levels of population fragmentation and interaction patterns between partially isolated groups. PMID:26929364

  8. An Investigation into Node Strength Connectivity Correlation

    Institute of Scientific and Technical Information of China (English)

    SHI Jian-Jun; WANG Yong-Li; HE Da-Ren

    2009-01-01

    We propose investigating the node strength connectivity correlation by a resource-allocation method and the traditional multiple edge method, respectively. A rough analysis suggests that the resource-allocation node strength connectivity correlation is always negative, which is different from the connectivity correlation of the traditional multiple edge node strength (it can show either positive, negative or no correlation). As examples,empirical investigation results for two real world cooperation-competition networks (the 2004 Athens Olympic Games network and the mixed drink network) are presented. We believe that the resource-allocation node strength connectivity correlation can serve as a description of the relative crackajack distribution, which is a complementarity of the traditional multiple edge one.

  9. Bound on m-restricted Edge Connectivity

    Institute of Scientific and Technical Information of China (English)

    Jian-ping Ou; Fu-ji Zhang

    2003-01-01

    An m-restricted edge cut is an edge cut that separates a connected graph into a disconnected one with no components having order less than m. m-restricted edge connectivity λm is the cardinality of a minimum m-restricted edge cut. Let G be a connected k-regular graph of order at least 2m that contains m-restricted edge cuts and X be a subgraph of G. Let( )(X) denote the number of edges with one end in X and the other not in X and ξm = min{( )(X): X is a connected vertex-induced subgraph of order m}. It is proved in this paper that if G has girth at least m/2 + 2, then λm ≤ξm. The upper bound of λm is sharp.

  10. Application of Partially Connected Neural Network

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper focuses mainly on application of Partially Connected Backpropagation Neural Network (PCBP) instead of typical Fully Connected Neural Network (FCBP). The initial neural network is fully connected, after training with sample data using cross-entropy as error function, a clustering method is employed to cluster weights between inputs to hidden layer and from hidden to output layer, and connections that are relatively unnecessary are deleted, thus the initial network becomes a PCBP network.Then PCBP can be used in prediction or data mining by training PCBP with data that comes from database. At the end of this paper, several experiments are conducted to illustrate the effects of PCBP using Iris data set.

  11. Connecting and communicating after Typhoon Haiyan

    Directory of Open Access Journals (Sweden)

    Mariko Hall

    2014-02-01

    Full Text Available In the first month of the Typhoon Haiyan response, one of the priorities facing the international community was to re-establish internet connectivity in order to facilitate information sharing and the provision of assistance.

  12. MedlinePlus Connect: Technical Information

    Science.gov (United States)

    ... code can be submitted per request. Supports the HL7 Context-Aware Knowledge Retrieval (Infobutton) standard. Connects using ... How does it work? Responds to requests with XML, JSON, or JSONP, which implementers can use to ...

  13. Periodic words connected with the Fibonacci words

    Directory of Open Access Journals (Sweden)

    G. M. Barabash

    2016-06-01

    Full Text Available In this paper we introduce two families of periodic words (FLP-words of type 1 and FLP-words of type 2 that are connected with the Fibonacci words and investigated their properties.

  14. Comparing brains by matching connectivity profiles.

    Science.gov (United States)

    Mars, Rogier B; Verhagen, Lennart; Gladwin, Thomas E; Neubert, Franz-Xaver; Sallet, Jerome; Rushworth, Matthew F S

    2016-01-01

    The great promise of comparative neuroscience is to understand why brains differ by investigating the relations between variations in the organization of different brains, their evolutionary history, and their current ecological niche. For this approach to be successful, the organization of different brains needs to be quantifiable. Here, we present an approach to formally comparing the connectivity of different cortical areas across different brains. We exploit the fact that cortical regions can be characterized by the unique pattern of connectivity, the so-called connectivity fingerprint. By comparing connectivity fingerprints between cortical areas in the human and non-human primate brain we can identify between-species homologs, but also illustrate that is driving differences between species. We illustrate the approach by comparing the organization of the frontal cortex between humans and macaques, showing general similarities combined with some differences in the lateral frontal pole.

  15. Better models are more effectively connected models

    Science.gov (United States)

    Nunes, João Pedro; Bielders, Charles; Darboux, Frederic; Fiener, Peter; Finger, David; Turnbull-Lloyd, Laura; Wainwright, John

    2016-04-01

    The concept of hydrologic and geomorphologic connectivity describes the processes and pathways which link sources (e.g. rainfall, snow and ice melt, springs, eroded areas and barren lands) to accumulation areas (e.g. foot slopes, streams, aquifers, reservoirs), and the spatial variations thereof. There are many examples of hydrological and sediment connectivity on a watershed scale; in consequence, a process-based understanding of connectivity is crucial to help managers understand their systems and adopt adequate measures for flood prevention, pollution mitigation and soil protection, among others. Modelling is often used as a tool to understand and predict fluxes within a catchment by complementing observations with model results. Catchment models should therefore be able to reproduce the linkages, and thus the connectivity of water and sediment fluxes within the systems under simulation. In modelling, a high level of spatial and temporal detail is desirable to ensure taking into account a maximum number of components, which then enables connectivity to emerge from the simulated structures and functions. However, computational constraints and, in many cases, lack of data prevent the representation of all relevant processes and spatial/temporal variability in most models. In most cases, therefore, the level of detail selected for modelling is too coarse to represent the system in a way in which connectivity can emerge; a problem which can be circumvented by representing fine-scale structures and processes within coarser scale models using a variety of approaches. This poster focuses on the results of ongoing discussions on modelling connectivity held during several workshops within COST Action Connecteur. It assesses the current state of the art of incorporating the concept of connectivity in hydrological and sediment models, as well as the attitudes of modellers towards this issue. The discussion will focus on the different approaches through which connectivity

  16. The spin connection of twisted geometry

    OpenAIRE

    Haggard, Hal M.; Rovelli, Carlo; Vidotto, Francesca; Wieland, Wolfgang

    2012-01-01

    Twisted geometry is a piecewise-flat geometry less rigid than Regge geometry. In Loop Gravity, it provides the classical limit for each step of the truncation utilized in the definition of the quantum theory. We define the torsionless spin-connection of a twisted geometry. The difficulty given by the discontinuity of the triad is addressed by interpolating between triads. The curvature of the resulting spin connection reduces to the Regge curvature in the case of a Regge geometry.

  17. Regulation of synaptic connectivity by glia

    OpenAIRE

    Eroglu, Cagla; Barres, Ben A

    2010-01-01

    The human brain contains more than 100 trillion (1014) synaptic connections, which form all of its neural circuits. Neuroscientists have long been interested in how this complex synaptic web is weaved during development and remodelled during learning and disease. Recent studies have uncovered that glial cells are important regulators of synaptic connectivity. These cells are far more active than was previously thought and are powerful controllers of synapse formation, function, plasticity and...

  18. Univalent Biharmonic Mappings and Linearly Connected Domains

    Directory of Open Access Journals (Sweden)

    Zayid Abdulhadi

    2015-11-01

    Full Text Available A four times continuously differentiable complex valued function F = u + iv in a simply connected domain Ω is biharmonic if the laplacian of F is harmonic. Every biharmonic mapping F in Ω has the representation F = |z|^2 G + K, where G and K are harmonic in Ω. This paper investigates the relationship between the univalence of F and of K using the concept of linearly connected domains.

  19. Computational Unification: a Vision for Connecting Researchers

    OpenAIRE

    Troy III, Richard M.

    2004-01-01

    The extent to which the benefits of science can be fully realized depends critically upon the quality of the connection between researchers themselves and between researchers and members of the public. We believe that it is now possible to improve these connections on a community-wide and even world-wide basis through the use of an appropriate information management system. In this paper we explore the concepts and challenges, and propose an architecture for the implementation of such a syste...

  20. SERVIR Town Hall - Connecting Space to Village

    Science.gov (United States)

    Limaye, Ashutosh S.; Searby, Nancy D.; Irwin, Daniel; Albers, Cerese

    2013-01-01

    SERVIR, a joint NASA-USAID project, strives to improve environmental decision making through the use of Earth observations, models, and geospatial technology innovations. SERVIR connects these assets with the needs of end users in Mesoamerica, East Africa, and Hindu Kush-Himalaya regions. This Town Hall meeting will engage the AGU community by exploring examples of connecting Space to Village with SERVIR science applications.

  1. Autaptic Connections Shift Network Excitability and Bursting

    OpenAIRE

    Wiles, Laura; Gu, Shi; Pasqualetti, Fabio; Bassett, Danielle S.; Meaney, David F.

    2016-01-01

    Network architecture forms a critical constraint on neuronal function. Here we examine the role of structural autapses, when a neuron synapses onto itself, in driving network-wide bursting behavior. Using a simple spiking model of neuronal activity, we study how autaptic connections affect activity patterns, and evaluate if neuronal degree or controllability are significant factors that affect changes in bursting from these autaptic connections. We observed that adding increasing numbers of a...

  2. Zone heated diesel particulate filter electrical connection

    Science.gov (United States)

    Gonze, Eugene V.; Paratore, Jr., Michael J.

    2010-03-30

    An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

  3. Adiabatic Connection for Strictly-Correlated Electrons

    OpenAIRE

    Liu, Zhenfei; Burke, Kieron

    2009-01-01

    Modern density functional theory (DFT) calculations employ the Kohn-Sham (KS) system of non-interacting electrons as a reference, with all complications buried in the exchange-correlation energy (Exc). The adiabatic connection formula gives an exact expression for Exc. We consider DFT calculations that instead employ a reference of strictly-correlated electrons. We define a "decorrelation energy" that relates this reference to the real system, and derive the corresponding adiabatic connection...

  4. Admissibility, stable units and connected components

    CERN Document Server

    Xarez, J J

    2011-01-01

    Consider a reflection from a finitely-complete category $\\mathbb{C}$ into its full subcategory $\\mathbb{M}$, with unit $\\eta :1_\\mathbb{C}\\rightarrow HI$. Suppose there is a left-exact functor $U$ into the category of sets, such that $UH$ reflects isomorphisms and $U(\\eta_C)$ is a surjection, for every $C\\in\\mathbb{C}$. If, in addition, all the maps $\\mathbb{M}(T,M)\\rightarrow \\mathbf{Set}(1,U(M))$ induced by the functor $UH$ are surjections, where $T$ and 1 are respectively terminal objects in $\\mathbb{C}$ and $\\mathbf{Set}$, for every object $M$ in the full subcategory $\\mathbb{M}$, then it is true that: the reflection $H\\vdash I$ is semi-left-exact (admissible in the sense of categorical Galois theory) if and only if its connected components are "connected"; it has stable units if and only if any finite product of connected components is "connected". Where the meaning of "connected" is the usual in categorical Galois theory, and the definition of connected component with respect to the ground structure wil...

  5. Service connectivity architecture for mobile augmented reality

    Science.gov (United States)

    Turunen, Tuukka; Pyssysalo, Tino; Roening, Juha

    2001-06-01

    Mobile augmented reality can be utilized in a number of different services, and it provides a lot of added value compared to the interfaces used in mobile multimedia today. Intelligent service connectivity architecture is needed for the emerging commercial mobile augmented reality services, to guarantee mobility and interoperability on a global scale. Some of the key responsibilities of this architecture are to find suitable service providers, to manage the connection with and utilization of such providers, and to allow smooth switching between them whenever the user moves out of the service area of the service provider she is currently connected to. We have studied the potential support technologies for such architectures and propose a way to create an intelligent service connectivity architecture based on current and upcoming wireless networks, an Internet backbone, and mechanisms to manage service connectivity in the upper layers of the protocol stack. In this paper, we explain the key issues of service connectivity, describe the properties of our architecture, and analyze the functionality of an example system. Based on these, we consider our proposition a good solution to the quest for global interoperability in mobile augmented reality services.

  6. Wireless device connection problems and design solutions

    Science.gov (United States)

    Song, Ji-Won; Norman, Donald; Nam, Tek-Jin; Qin, Shengfeng

    2016-09-01

    Users, especially the non-expert users, commonly experience problems when connecting multiple devices with interoperability. While studies on multiple device connections are mostly concentrated on spontaneous device association techniques with a focus on security aspects, the research on user interaction for device connection is still limited. More research into understanding people is needed for designers to devise usable techniques. This research applies the Research-through-Design method and studies the non-expert users' interactions in establishing wireless connections between devices. The "Learning from Examples" concept is adopted to develop a study focus line by learning from the expert users' interaction with devices. This focus line is then used for guiding researchers to explore the non-expert users' difficulties at each stage of the focus line. Finally, the Research-through-Design approach is used to understand the users' difficulties, gain insights to design problems and suggest usable solutions. When connecting a device, the user is required to manage not only the device's functionality but also the interaction between devices. Based on learning from failures, an important insight is found that the existing design approach to improve single-device interaction issues, such as improvements to graphical user interfaces or computer guidance, cannot help users to handle problems between multiple devices. This study finally proposes a desirable user-device interaction in which images of two devices function together with a system image to provide the user with feedback on the status of the connection, which allows them to infer any required actions.

  7. Holistic Connectivity Controller for Multirobot Dispersion

    Directory of Open Access Journals (Sweden)

    Zhenqiang Mi

    2013-01-01

    Full Text Available Dispersion of mobile robots in a certain formation is prerequisite in many applications; one of the most important issues during the entire process is to maintain the interagent connections, as well as to restore them whenever they were broken. We investigate the aforementioned problem in this work by designing a holistic connectivity controller (HCC to regulate and restore the interagent connections during the dispersion of the mobile network. HCC consists of two core structures. Firstly, to illustrate the multirobot dispersion, we adopt the distributed link removal algorithm (DLRA, which is able to remove redundant links in the multirobot network to facilitate the dispersion and only requires local information of no more than two-hop neighbors. Secondly, the proposed approach is extended to the problem of connectivity restoration with consideration of simultaneous failure of multiple agents. A connectivity restoration strategy is proposed, and then the recoverability of network connectivity is investigated. The proposed HCC has also integrated motion controller to regulate the movement of the mobile robots, so that interrobot collisions can be effectively avoided. Theoretical analysis and computer simulations have confirmed the efficiency and scalability of the proposed schemes.

  8. P-connection on Riemannian almost product manifolds

    CERN Document Server

    Mekerov, Dimitar

    2009-01-01

    In the present work, we introduce a linear connection (preserving the almost product structure and the Riemannian metric) on Riemannian almost product manifolds. This connection, called P-connection, is an analogue of the first canonical connection of Lichnerowicz in the Hermitian geometry and the B-connection in the geometry of the almost complex manifolds with Norden metric. Particularly, we consider the P-connection on a the class of manifolds with nonintegrable almost product structure.

  9. 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

  10. Resting state functional connectivity in anorexia nervosa.

    Science.gov (United States)

    Phillipou, Andrea; Abel, Larry Allen; Castle, David Jonathan; Hughes, Matthew Edward; Nibbs, Richard Grant; Gurvich, Caroline; Rossell, Susan Lee

    2016-05-30

    Anorexia Nervosa (AN) is a serious psychiatric illness characterised by a disturbance in body image, a fear of weight gain and significantly low body weight. The factors involved in the genesis and maintenance of AN are unclear, though the potential neurobiological underpinnings of the condition are of increasing interest. Through the investigation of functional connectivity of the brain at rest, information relating to neuronal communication and integration of information that may relate to behaviours and cognitive symptoms can be explored. The aim of this study was to investigate functional connectivity of the default mode network, and sensorimotor and visual networks in AN. 26 females with AN and 27 healthy control participants matched for age, gender and premorbid intelligence underwent a resting state functional magnetic resonance imaging scan. Default mode network functional connectivity did not differ between groups. AN participants displayed reduced functional connectivity between the sensorimotor and visual networks, in comparison to healthy controls. This finding is discussed in terms of differences in visuospatial processing in AN and the distortion of body image experienced by these individuals. Overall, the findings suggest that sensorimotor and visual network connectivity may be related to visuospatial processing in AN, though, further research is required. PMID:27111812

  11. Connectivity: An emerging concept for physiotherapy practice.

    Science.gov (United States)

    Nicholls, David A; Atkinson, Karen; Bjorbækmo, Wenche S; Gibson, Barbara E; Latchem, Julie; Olesen, Jens; Ralls, Jenny; Setchell, Jennifer

    2016-01-01

    Having spent their first century anchored to a biomedical model of practice, physiotherapists have been increasingly interested in exploring new models and concepts that will better equip them for serving the health-care needs of 21st century clients/patients. Connectivity offers one such model. With an extensive philosophical background in phenomenology, symbolic interactionism, structuralism, and postmodern research, connectivity resists the prevailing western biomedical view that health professionals should aim to increase people's independence and autonomy, preferring instead to identify and amplify opportunities for collaboration and co-dependence. Connectivity critiques the normalization that underpins modern health care, arguing that our constant search for deviance is building stigma and discrimination into our everyday practice. It offers provocative opportunities for physiotherapists to rethink some of the fundamental tenets of their profession and better align physiotherapy with 21st century societal expectations. In this paper, we provide a background to the place connectivity may play in future health care, and most especially future physiotherapy practice. The paper examines some of the philosophical antecedents that have made connectivity an increasingly interesting and challenging concept in health care today. PMID:27050116

  12. Connectivity in finite ad-hoc networks

    Institute of Scientific and Technical Information of China (English)

    WANG HanXing; LU GuiLin; JIA WeiJia; ZHAO Wei

    2008-01-01

    Research on ad-hoc network connectivity has mainly focused on asymptotic results In the number of nodes in the network. For a one-dimensional ad-hoc network G1, assuming all the nodes are Independently uniform distributed in a closed Interval [O, Z](z ∈ R+), we derive a generic formula for the probability that the network is connected. The finite connected ad-hoc networks is analyzed. And we separately suggest necessary conditions to make the ad-hoc network to be connected in one and two dimensional cases, facing possible failed nodes (f-nodes). Based on the necessary condition and unit-disk assumption for the node transmission, we prove that the nodes of the connected two-dimensional ad-hoc networks (G2) can be di-vided into at most five different groups. For an f-node n0 in either of the five groups, we derive a close formula for the probability that there is at least one route between a pair of nodes in G2 - {no}.

  13. Connected Car: Quantified Self becomes Quantified Car

    Directory of Open Access Journals (Sweden)

    Melanie Swan

    2015-02-01

    Full Text Available The automotive industry could be facing a situation of profound change and opportunity in the coming decades. There are a number of influencing factors such as increasing urban and aging populations, self-driving cars, 3D parts printing, energy innovation, and new models of transportation service delivery (Zipcar, Uber. The connected car means that vehicles are now part of the connected world, continuously Internet-connected, generating and transmitting data, which on the one hand can be helpfully integrated into applications, like real-time traffic alerts broadcast to smartwatches, but also raises security and privacy concerns. This paper explores the automotive connected world, and describes five killer QS (Quantified Self-auto sensor applications that link quantified-self sensors (sensors that measure the personal biometrics of individuals like heart rate and automotive sensors (sensors that measure driver and passenger biometrics or quantitative automotive performance metrics like speed and braking activity. The applications are fatigue detection, real-time assistance for parking and accidents, anger management and stress reduction, keyless authentication and digital identity verification, and DIY diagnostics. These kinds of applications help to demonstrate the benefit of connected world data streams in the automotive industry and beyond where, more fundamentally for human progress, the automation of both physical and now cognitive tasks is underway.

  14. 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...

  15. A systematic framework for functional connectivity measures

    Directory of Open Access Journals (Sweden)

    Huifang Elizabeth Wang

    2014-12-01

    Full Text Available Various methods have been proposed to characterize the functional connectivity between nodes in a network measured with different modalities (electrophysiology, functional magnetic resonance imaging etc.. Since different measures of functional connectivity yield different results for the same dataset, it is important to assess when and how they can be used. In this work, we provide a systematic framework for evaluating the performance of a large range of functional connectivity measures – based upon a comprehensive portfolio of models generating measurable responses. Specifically, we benchmarked 42 methods using 10,000 simulated datasets from 5 different types of generative models with different connectivity structures. Since all functional connectivity methods require the setting of some parameters (window size and number, model order etc., we first optimized these parameters using performance criteria based upon (threshold free ROC analysis. We then evaluated the performance of the methods on data simulated with different types of models. Finally, we assessed the performance of the methods against different levels of signal-to-noise ratios and network configurations. A MATLAB toolbox is provided to perform such analyses using other methods and simulated datasets.

  16. A review of variables of urban street connectivity for spatial connection

    Science.gov (United States)

    Mohamad, W. S. N. W.; Said, I.

    2014-02-01

    Several studies on street connectivity in cities and towns have been modeled on topology, morphology, technology and psychology of people living in the urban environment. Street connectivity means the connection of streets that offers people alternative routes. However, there emerge difficulties to determine the suitable variables and analysis to be chosen in defining the accurate result for studies street connectivity. The aim of this paper is to identify variables of street connectivity by applying GIS and Space Syntax. This paper reviews the variables of street connectivity from 15 past articles done in 1990s to early 2000s from journals of nine disciplines on Environment and Behavior, Planning and Design, Computers, Environment and Urban Systems, Applied Earth Observation and Geo-information, Environment and Planning, Physica A: Statistical Mechanics and its Applications, Environmental Psychology, Social Science and Medicine and Building and Environment. From the review, there are four variables found for street connectivity: link (streets-streets, street-nodes or node-streets, nodes-nodes), accessibility, least-angle, and centrality. Space syntax and GIS are suitable tools to analyze the four variables relating to systematic street systems for pedestrians. This review implies that planners of the street systems, in the aspect of street connectivity in cities and towns, should consider these four variables.

  17. Connecting to Our Community: Utilizing Photovoice as a Pedagogical Tool to Connect College Students to Science

    Science.gov (United States)

    Cook, Kristin; Quigley, Cassie

    2013-01-01

    In this study, we investigated the ways in which university students connected with science through the use of photovoice (Wang & Burris, 1994) as a pedagogical tool. Results indicated that students came to appreciate their connections to the science that operates in their lives as they reflected on and became empowered with regard to the science…

  18. A review of variables of urban street connectivity for spatial connection

    International Nuclear Information System (INIS)

    Several studies on street connectivity in cities and towns have been modeled on topology, morphology, technology and psychology of people living in the urban environment. Street connectivity means the connection of streets that offers people alternative routes. However, there emerge difficulties to determine the suitable variables and analysis to be chosen in defining the accurate result for studies street connectivity. The aim of this paper is to identify variables of street connectivity by applying GIS and Space Syntax. This paper reviews the variables of street connectivity from 15 past articles done in 1990s to early 2000s from journals of nine disciplines on Environment and Behavior, Planning and Design, Computers, Environment and Urban Systems, Applied Earth Observation and Geo-information, Environment and Planning, Physica A: Statistical Mechanics and its Applications, Environmental Psychology, Social Science and Medicine and Building and Environment. From the review, there are four variables found for street connectivity: link (streets-streets, street-nodes or node-streets, nodes-nodes), accessibility, least-angle, and centrality. Space syntax and GIS are suitable tools to analyze the four variables relating to systematic street systems for pedestrians. This review implies that planners of the street systems, in the aspect of street connectivity in cities and towns, should consider these four variables

  19. Healthcare e-commerce: connecting with patients.

    Science.gov (United States)

    Joslyn, J S

    2001-01-01

    Electronically connecting with patients is a challenging frontier at which technical hurdles are probably exceeded by political, legal, and other barriers. The rise of consumerism, however, compels a response focused more on revenue and strategic advantage than on pure cost savings. Among the difficulties faced by providers is choosing among various models of connectivity and component function. Emerging models include "free-floating" personal medical records largely independent of the office-based physician, systems with compatible and intertwined physician and consumer relationships using an application services provider office practice system, and systems that connect patients and providers through e-mail, office triage, prescription refills, scheduling, and so on. This article discusses these and other combinations of technology that significantly overcome the barriers involved and that may be woven together to provide solutions uniquely suited to various competitive situations.

  20. AMTEC vapor-vapor series connected cells

    Science.gov (United States)

    Underwood, Mark L.; Williams, Roger M.; Ryan, Margaret A.; Nakamura, Barbara J.; Oconnor, Dennis E.

    1995-08-01

    An alkali metal thermoelectric converter (AMTEC) having a plurality of cells structurally connected in series to form a septum dividing a plenum into two chambers, and electrically connected in series, is provided with porous metal anodes and porous metal cathodes in the cells. The cells may be planar or annular, and in either case a metal alkali vapor at a high temperature is provided to the plenum through one chamber on one side of the wall and returned to a vapor boiler after condensation at a chamber on the other side of the wall in the plenum. If the cells are annular, a heating core may be placed along the axis of the stacked cells. This arrangement of series-connected cells allows efficient generation of power at high voltage and low current.

  1. LR: Compact connectivity representation for triangle meshes

    Energy Technology Data Exchange (ETDEWEB)

    Gurung, T; Luffel, M; Lindstrom, P; Rossignac, J

    2011-01-28

    We propose LR (Laced Ring) - a simple data structure for representing the connectivity of manifold triangle meshes. LR provides the option to store on average either 1.08 references per triangle or 26.2 bits per triangle. Its construction, from an input mesh that supports constant-time adjacency queries, has linear space and time complexity, and involves ordering most vertices along a nearly-Hamiltonian cycle. LR is best suited for applications that process meshes with fixed connectivity, as any changes to the connectivity require the data structure to be rebuilt. We provide an implementation of the set of standard random-access, constant-time operators for traversing a mesh, and show that LR often saves both space and traversal time over competing representations.

  2. Healthcare e-commerce: connecting with patients.

    Science.gov (United States)

    Joslyn, J S

    2001-01-01

    Electronically connecting with patients is a challenging frontier at which technical hurdles are probably exceeded by political, legal, and other barriers. The rise of consumerism, however, compels a response focused more on revenue and strategic advantage than on pure cost savings. Among the difficulties faced by providers is choosing among various models of connectivity and component function. Emerging models include "free-floating" personal medical records largely independent of the office-based physician, systems with compatible and intertwined physician and consumer relationships using an application services provider office practice system, and systems that connect patients and providers through e-mail, office triage, prescription refills, scheduling, and so on. This article discusses these and other combinations of technology that significantly overcome the barriers involved and that may be woven together to provide solutions uniquely suited to various competitive situations. PMID:11338911

  3. Quantifying Riverscape Connectivity with Graph Theory

    Science.gov (United States)

    Carbonneau, P.; Milledge, D.; Sinha, R.; Tandon, S. K.

    2013-12-01

    Fluvial catchments convey fluxes of water, sediment, nutrients and aquatic biota. At continental scales, crustal topography defines the overall path of channels whilst at local scales depositional and/or erosional features generally determine the exact path of a channel. Furthermore, constructions such as dams, for either water abstraction or hydropower, often have a significant impact on channel networks.The concept of ';connectivity' is commonly invoked when conceptualising the structure of a river network.This concept is easy to grasp but there have been uneven efforts across the environmental sciences to actually quantify connectivity. Currently there have only been a few studies reporting quantitative indices of connectivity in river sciences, notably, in the study of avulsion processes. However, the majority of current work describing some form of environmental connectivity in a quantitative manner is in the field of landscape ecology. Driven by the need to quantify habitat fragmentation, landscape ecologists have returned to graph theory. Within this formal setting, landscape ecologists have successfully developed a range of indices which can model connectivity loss. Such formal connectivity metrics are currently needed for a range of applications in fluvial sciences. One of the most urgent needs relates to dam construction. In the developed world, hydropower development has generally slowed and in many countries, dams are actually being removed. However, this is not the case in the developing world where hydropower is seen as a key element to low-emissions power-security. For example, several dam projects are envisaged in Himalayan catchments in the next 2 decades. This region is already under severe pressure from climate change and urbanisation, and a better understanding of the network fragmentation which can be expected in this system is urgently needed. In this paper, we apply and adapt connectivity metrics from landscape ecology. We then examine the

  4. Evolution Strategies in the Multipoint Connections Routing

    Directory of Open Access Journals (Sweden)

    L. Krulikovska

    2010-09-01

    Full Text Available Routing of multipoint connections plays an important role in final cost and quality of a found connection. New algorithms with better results are still searched. In this paper, a possibility of using the evolution strategies (ES for routing is presented. Quality of found connection is evaluated from the view of final cost and time spent on a searching procedure. First, parametrical analysis of results of the ES are discussed and compared with the Prim’s algorithm, which was chosen as a representative of the deterministic routing algorithms. Second, ways for improving the ES are suggested and implemented. The obtained results are reviewed. The main improvements are specified and discussed in conclusion.

  5. 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

  6. Connected brains and minds – the UMCD repository for brain connectivity matrices

    Science.gov (United States)

    Brown, Jesse A.; Van Horn, John D.

    2016-01-01

    We describe the USC Multimodal Connectivity Database (http://umcd.humanconnectomeproject.org ), an interactive web-based platform for brain connectivity matrix sharing and analysis. The site enables users to download connectivity matrices shared by other users, upload matrices from their own published studies, or select a specific matrix and perform a realtime graph theory-based analysis and visualization of network properties. The data shared on the site span a broad spectrum of functional and structural brain connectivity information from humans across the entire age range (fetal to age 89), representing an array of different neuropsychiatric and neurodegenerative disease populations (autism spectrum disorder, ADHD, and APOE-4 carriers). An analysis combining 7 different datasets shared on the site illustrates the diversity of the data and the potential for yielding deeper insight by assessing new connectivity matrices with respect to population-wide network properties represented in the UMCD. PMID:26311606

  7. Connected brains and minds--The UMCD repository for brain connectivity matrices.

    Science.gov (United States)

    Brown, Jesse A; Van Horn, John D

    2016-01-01

    We describe the USC Multimodal Connectivity Database (http://umcd.humanconnectomeproject.org), an interactive web-based platform for brain connectivity matrix sharing and analysis. The site enables users to download connectivity matrices shared by other users, upload matrices from their own published studies, or select a specific matrix and perform a real-time graph theory-based analysis and visualization of network properties. The data shared on the site span a broad spectrum of functional and structural brain connectivity information from humans across the entire age range (fetal to age 89), representing an array of different neuropsychiatric and neurodegenerative disease populations (autism spectrum disorder, ADHD, and APOE-4 carriers). An analysis combining 7 different datasets shared on the site illustrates the diversity of the data and the potential for yielding deeper insight by assessing new connectivity matrices with respect to population-wide network properties represented in the UMCD. PMID:26311606

  8. AARP iPad Tech to Connect

    CERN Document Server

    Boyd, Barbara

    2012-01-01

    The world is at your fingertips with iPad! AARP iPad: Tech to Connect introduces you to the world?s most popular tablet device, the iPad, and all the amazing things it has to offer. In clear, non-technical language, this book guides you through registering and setting up your iPad, getting acquainted with the multitouch interface, navigating around the screen, finding and downloading apps, reading books, listening to music, watching videos, surfing the web, and communicating with friends and family. Developed in partnership with AARP and dedicated to helping readers stay connected with friends

  9. Supervised hub-detection for brain connectivity

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Liptrot, Matthew George; Reislev, Nina Linde;

    2016-01-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied......-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any...

  10. Political Connections and Investment in Rural Vietnam

    DEFF Research Database (Denmark)

    Markussen, Thomas; Tarp, Finn

    behaviour in environments with developing institutions and markets. They also suggest the presence of an untapped potential for economic development: if households without connections could obtain equally strong property rights and access to credit and insurance as the well-connected households, investment......This paper uses household panel data from rural Vietnam to explore the effects of having a relative in a position of political or bureaucratic power on farmers’ agricultural investment decisions. Our main result is that households significantly increase their investment in land improvement...

  11. Cold electrical connection for FAIR/ SIS100

    CERN Document Server

    Kauschke, M; Quack, H

    2009-01-01

    The Facility of Antiproton and Ion Research (FAIR) will be an international centre for atomic-, plasma- and nuclear- physics, located next to Gesellschaft für Schwerionenforschung (GSI), Darmstadt. FAIR will be composed from two synchrotrons and four storage rings. Both synchrotrons, SIS100 and SIS300, are designed with superconducting magnets. For radiation protection reasons and landscaping restrictions the synchrotrons will be placed underground, whereas the power supplies will be placed within three service buildings above ground level. To save space and refrigeration power a superconducting electrical connection will be implemented. The mechanical and thermal design of this connection will be presented in the paper.

  12. The canonical connection in quantum mechanics

    CERN Document Server

    Lévai, Peter; Tsutsui, I; Levay, Peter; McMullan, David; Tsutsui, Izumi

    1995-01-01

    In this paper we investigate the form of induced gauge fields that arises in two types of quantum systems. In the first we consider quantum mechanics on coset spaces G/H, and argue that G-invariance is central to the emergence of the H-connection as induced gauge fields in the different quantum sectors. We then demonstrate why the same connection, now giving rise to the non-abelian generalization of Berry's phase, can also be found in systems which have slow variables taking values in such a coset space.

  13. The canonical connection in quantum mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Levay, P. [Budapesti Mueszaki Egyetem, Budapest (Hungary); Mcmullan, D.; Tsutsui, Izumi

    1995-04-01

    In this paper we investigate the form of induced gauge fields that arises in two types of quantum systems. In the first we consider quantum mechanics on coset spaces G/H, and argue that G-invariance is central to the emergence of the H-connection as induced gauge fields in the different quantum sectors. We then demonstrate why the same connection, now giving rise to the non-abelian generalization of Berry`s phase, can also be found in systems which have slow variables taking values in such a coset space. (author).

  14. High-throughput dual-colour precision imaging for brain-wide connectome with cytoarchitectonic landmarks at the cellular level

    OpenAIRE

    Gong, Hui; Xu, Dongli; Yuan, Jing; Li, Xiangning; Guo, Congdi; Peng, Jie; Li, Yuxin; Schwarz, Lindsay A.; Li, Anan; Hu, Bihe; Xiong, Benyi; Sun, Qingtao; Zhang, Yalun; Liu, Jiepeng; Zhong, Qiuyuan

    2016-01-01

    The precise annotation and accurate identification of neural structures are prerequisites for studying mammalian brain function. The orientation of neurons and neural circuits is usually determined by mapping brain images to coarse axial-sampling planar reference atlases. However, individual differences at the cellular level likely lead to position errors and an inability to orient neural projections at single-cell resolution. Here, we present a high-throughput precision imaging method that c...

  15. 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.

  16. Linear Connections on Normal Almost Contact Manifolds with Norden Metric

    CERN Document Server

    Teofilova, Marta

    2011-01-01

    Families of linear connections are constructed on almost contact manifolds with Norden metric. An analogous connection to the symmetric Yano connection is obtained on a normal almost contact manifold with Norden metric and closed structural 1-form. The curvature properties of this connection are studied on two basic classes of normal almost contact manifolds with Norden metric.

  17. On the correspondence between infinitesimal and integral description of connections

    International Nuclear Information System (INIS)

    We point out that there is no equivalence between infinitesimal (connection form or distribution of horizontal subspaces) and integral (path formalism) description of connections. There will be a one-to-one correspondence if the notion of (infinitesimal) connection is generalized. This is done by introducing ''infinitesimally non-linear'' connections. (author)

  18. Inequalities, Absolute Value, and Logical Connectives.

    Science.gov (United States)

    Parish, Charles R.

    1992-01-01

    Presents an approach to the concept of absolute value that alleviates students' problems with the traditional definition and the use of logical connectives in solving related problems. Uses a model that maps numbers from a horizontal number line to a vertical ray originating from the origin. Provides examples solving absolute value equations and…

  19. Exploring Poetry: The Reading and Writing Connection.

    Science.gov (United States)

    Ediger, Marlow

    Connecting reading and writing has become an important trend in teaching the language arts. Poetry, as a salient facet of the reading curriculum, integrates well with different purposes in writing. Poetry read aloud to students can assist learners to enjoy reading activities and develop the feeling and aesthetic dimension of learning, among other…

  20. Preservice Teachers Connecting Mathematics and Drumming

    Science.gov (United States)

    Marshall, Anne Marie

    2014-01-01

    Increasingly, elementary classroom teachers are being called to teach a myriad of subjects, including visual art, dance, and music. Preservice teachers must be prepared to teach and integrate multiple subjects. To that end, preservice teachers will need experiences in their preparation that help them to see connections across content areas and…

  1. Quantized Abelian principle connections on Lorentzian manifolds

    Energy Technology Data Exchange (ETDEWEB)

    Benini, Marco [Pavia Univ. (Italy); Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Dappiaggi, Claudio [Pavia Univ. (Italy); Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Schenkel, Alexander [Bergische Univ., Wuppertal (Germany). Fachgruppe Mathematik

    2013-03-15

    We construct a covariant functor from a category of Abelian principal bundles over globally hyperbolic spacetimes to a category of *-algebras that describes quantized principal connections. We work within an appropriate differential geometric setting by using the bundle of connections and we study the full gauge group, namely the group of vertical principal bundle automorphisms. Properties of our functor are investigated in detail and, similar to earlier works, it is found that due to topological obstructions the locality property of locally covariant quantum field theory is violated. Furthermore, we prove that, for Abelian structure groups containing a nontrivial compact factor, the gauge invariant Borchers- Uhlmann algebra of the vector dual of the bundle of connections is not separating on gauge equivalence classes of principal connections. We introduce a topological generalization of the concept of locally covariant quantum fields. As examples, we construct for the full subcategory of principal U(1)-bundles two natural transformations from singular homology functors to the quantum field theory functor that can be interpreted as the Euler class and the electric charge. In this case we also prove that the electric charges can be consistently set to zero, which yields another quantum field theory functor that satisfies all axioms of locally covariant quantum field theory.

  2. Connecting Reading and Writing: A Case Study

    Science.gov (United States)

    Li, Zhanfang

    2015-01-01

    Connecting reading and writing, proposed by many scholars, is realized in this case study. The 30 participants in this study are the English majors of the third year in one School of Foreign Languages in Beijing. They are encouraged to write journals every week, based on the source text materials in their Intensive Reading class, with the final…

  3. Parity and the spin{statistics connection

    Indian Academy of Sciences (India)

    J A Morgan

    2005-09-01

    A simple demonstration of the spin-statistics connection for general causal fields is obtained by using the parity operation to exchange spatial coordinates in the scalar product of a locally commuting field operator, evaluated at position x, with the same field operator evaluated at -x, at equal times.

  4. "Scars" connect classical and quantum theory

    CERN Multimedia

    Monteiro, T

    1990-01-01

    Chaotic systems are unstable and extremely sensitive to initial condititions. So far, scientists have been unable to demonstrate that the same kind of behaviour exists in quantum or microscopic systems. New connections have been discovered though between classical and quantum theory. One is the phenomena of 'scars' which cut through the wave function of a particle (1 page).

  5. Working Connections: Class of 2002. Project Brief.

    Science.gov (United States)

    Becker, Kristin; Barnett, Lynn

    Working Connections is a program resulting from a partnership between the American Association of Community Colleges (AACC) and the Microsoft Corporation. The program was designed to help increase the number of skilled information technology (IT) workers by providing focused training in IT careers. Since 1998, AACC and Microsoft have awarded cash…

  6. 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 either…

  7. Clusters, Connectivity and Catch-up

    DEFF Research Database (Denmark)

    Lorenzen, Mark; Mudambi, Ram

    2013-01-01

    In this article, we make two important contributions to the literature on clusters. First, we provide a broader theory of cluster connectivity that has hitherto focused on organization-based pipelines and MNE subsidiaries, by including linkages in the form of personal relationships. Second, we us...

  8. Learning and the Teacher-Student Connection

    Science.gov (United States)

    Protheroe, Nancy

    2005-01-01

    A critical element in effective teaching is establishing positive connections with students, particularly those at risk of failure. This article presents the findings and suggestions of researchers who have examined the practices and impact of caring teachers, and how their students perceive them.

  9. A Scheme for Connecting Quantum Components

    Institute of Scientific and Technical Information of China (English)

    TAN Xiao-Hui; FANG Xi-Ming; WANG Guo-You

    2006-01-01

    @@ We propose an approach to connect components of a quantum computer by using a linear cluster state, with which an arbitrary N-particle state can be perfectly propagated between quantum components in two ways that are based on feedback measurements and local transformation.

  10. GOOSE: Semantic search on Internet connected sensors

    NARCIS (Netherlands)

    Schutte, K.; Bomhof, F.W.; Burghouts, G.J.; Diggelen, J. van; Hiemstra, P.; Hof, J. van 't; Kraaij, W.; Pasman, K.H.W.; Smith, A.J.E.; Versloot, C.A.; Wit, J.J. de

    2013-01-01

    More and more sensors are getting Internet connected. Examples are cameras on cell phones, CCTV cameras for traffic control as well as dedicated security and defense sensor systems. Due to the steadily increasing data volume, human exploitation of all this sensor data is impossible for effective mis

  11. [Prosthetic dilemmas. Connecting natural teeth and implants

    NARCIS (Netherlands)

    Cune, M.S.; Putter, C de; Verhoeven, J.W.; Meijer, G.J.

    2008-01-01

    In clinical practice, the prognosis seems, with some reservations, to be comparable for tooth-implant and implant-implant supported bridges in the middle-long term.This conclusion seems particularly valid for tooth-implant bridges in free-end situations, where a single implant is connected with a to

  12. Precentral gyrus functional connectivity signatures of autism

    Directory of Open Access Journals (Sweden)

    Mary Beth eNebel

    2014-05-01

    Full Text Available Motor impairments are prevalent in children with autism spectrum disorders (ASD and are perhaps the earliest symptoms to develop. In addition, motor skills relate to the communicative/social deficits at the core of ASD diagnosis, and these behavioral deficits may reflect abnormal connectivity within brain networks underlying motor control and learning. Despite the fact that motor abnormalities in ASD are well-characterized, there remains a fundamental disconnect between the complexity of the clinical presentation of ASD and the underlying neurobiological mechanisms. In this study, we examined connectivity within and between functional subregions of a key component of the motor control network, the precentral gyrus, using resting state functional Magnetic Resonance Imaging data collected from a large, heterogeneous sample of individuals with ASD as well as neurotypical controls. We found that the strength of connectivity within and between distinct functional subregions of the precentral gyrus was related to ASD diagnosis and to the severity of ASD traits. In particular, connectivity involving the dorsomedial (lower limb/trunk subregion was abnormal in ASD individuals as predicted by models using a dichotomous variable coding for the presence of ASD, as well as models using symptom severity ratings. These findings provide further support for a link between motor and social/communicative abilities in ASD.

  13. Connecting and Communicating with Students on Facebook

    Science.gov (United States)

    Miller, Sarah Elizabeth; Jensen, Lauren A.

    2007-01-01

    Facebook is a social network that connects people with other people. Librarians have created Facebook Groups to share ideas and to debate how to use this resource as a potential marketing and/or reference tool. Based on conversations among these librarians, it appears that student response to library outreach on this medium is lackluster at best,…

  14. Connection preserving actions are topologically engaging

    CERN Document Server

    Candel, A

    2012-01-01

    Topologically and geometrically engaging actions have proved to be useful to obtain rigidity results for semisimple Lie group actions. We show that the action of a simple noncompact Lie group on a compact manifold preserving a unimodular rigid geometric structure of algebraic type (e.g. a connection together with a volume density) is topologically engaging on an open conull dense set.

  15. Supervised hub-detection for brain connectivity

    Science.gov (United States)

    Kasenburg, Niklas; Liptrot, Matthew; Reislev, Nina Linde; Garde, Ellen; Nielsen, Mads; Feragen, Aasa

    2016-03-01

    A structural brain network consists of physical connections between brain regions. Brain network analysis aims to find features associated with a parameter of interest through supervised prediction models such as regression. Unsupervised preprocessing steps like clustering are often applied, but can smooth discriminative signals in the population, degrading predictive performance. We present a novel hub-detection optimized for supervised learning that both clusters network nodes based on population level variation in connectivity and also takes the learning problem into account. The found hubs are a low-dimensional representation of the network and are chosen based on predictive performance as features for a linear regression. We apply our method to the problem of finding age-related changes in structural connectivity. We compare our supervised hub-detection (SHD) to an unsupervised hub-detection and a linear regression using the original network connections as features. The results show that the SHD is able to retain regression performance, while still finding hubs that represent the underlying variation in the population. Although here we applied the SHD to brain networks, it can be applied to any network regression problem. Further development of the presented algorithm will be the extension to other predictive models such as classification or non-linear regression.

  16. Surprising Connections between Partitions and Divisors

    Science.gov (United States)

    Osler, Thomas J.; Hassen, Abdulkadir; Chandrupatla, Tirupathi R.

    2007-01-01

    The sum of the divisors of a positive integer is one of the most interesting concepts in multiplicative number theory, while the number of ways of expressing a number as a sum is a primary topic in additive number theory. In this article, we describe some of the surprising connections between and similarities of these two concepts.

  17. Some results of semilocally simply connected property

    Directory of Open Access Journals (Sweden)

    Azam Etemad Dehkordy

    2014-07-01

    Full Text Available If we consider some special conditions, we can assume fundamental group of atopological space as a new topological space. In this paper, we will present a number oftheorems in topological fundamental group related to semilocally simply connected propertyfor a topological space.

  18. Connectivity for Caribbean Countries : An Initial Assessment

    OpenAIRE

    Briceno-Garmendia, Cecilia; Bofinger, Heinrich C.; Cubas, Diana; Millan-Placci, Maria Florencia

    2014-01-01

    Every discussion of the Caribbean states considers their characteristics as sea-locked countries, small economies, highly vulnerable to natural disasters, and a geographic platform that calls for regional cooperation and integration. The Caribbean Sea is the most important vehicle and the most challenging obstacle Caribbean countries have to connect with the world. This report measures and...

  19. Classroom Activity Connections: Lessons from Fluorescence

    Science.gov (United States)

    MacCormac, Aoife; O'Brien, Emma; O'Kennedy, Richard

    2010-01-01

    This Classroom Activity Connections paper describes an extension to the "JCE" Classroom Activity #68 "Turning on the Light". A number of additional common items that display fluorescence under UV light are described, including fruits, vegetables, and seashells. Two classroom extensions on fluorescence are also described. From these activities,…

  20. Interhemispheric Functional Connectivity in Childhood Absence Epilepsy

    OpenAIRE

    J Gordon Millichap

    2011-01-01

    Using a blood oxygen level-dependent resting functional connectivity approach to analyze EEG-fMRI data, the properties of bihemispheric brain networks in 16 patients with childhood absence epilepsy (CAE) were investigated during the interictal period, in a study at Yale University School of Medicine, New Haven, CT.

  1. Emotional Connections in Higher Education Marketing

    Science.gov (United States)

    Durkin, Mark; McKenna, Seamas; Cummins, Darryl

    2012-01-01

    Purpose: Through examination of a case study this paper aims to describe a brand re-positioning exercise and explore how an emotionally driven approach to branding can help create meaningful connections with potential undergraduate students and can positively influence choice. Design/methodology/approach: The paper's approach is a case study…

  2. Modeling of Interdisciplinary Connections in Science Courses

    International Nuclear Information System (INIS)

    Graph model of interdisciplinary connections, and method of calculation quantitative parameters of model have described. The application of quantitative method to content of physics and mathematics has already done in this paper. The hierarchy of mathematical concepts used by the general physics course is established co according to two parameters – the bond strength (frequency of use) and the bond length (duration of use)

  3. MedlinePlus Connect: Web Service

    Science.gov (United States)

    ... in English or Spanish. MedlinePlus Connect will assume English is the language if it is not specified. If you wish ... but the requested format is JSON and the language is English: https://apps2.nlm.nih.gov/medlineplus/services/mpconnect_ ...

  4. 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. PMID:23501049

  5. Criminologyof the future: interdisciplinary scientific connections

    OpenAIRE

    Antonyan Yu.M.

    2014-01-01

    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 viewpoint...

  6. 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.

  7. Connections, Coherence, and Cognition in Composition.

    Science.gov (United States)

    Goldstein, Elizabeth; Perfetti, Charles

    In a study conducted to show the importance of sentence connections as a way of looking at a writer's cognitive processes, three devices used to achieve coherence in written discourse were compared and proved to be unequally effective. The devices were cohesion (use of a textual reference in a sentence that has an antecedent in a preceding…

  8. A quantitative measure of migratory connectivity

    OpenAIRE

    Ambrosini, Roberto; Møller, Anders Pape; Saino, Nicola

    2009-01-01

    A quantitative measure of migratory connectivity correspondence: Corresponding author. Tel.: +390264483464; fax: +390264483565. (Ambrosini, Roberto) (Ambrosini, Roberto) (M?ller, Anders Pape) (Saino, Nicola) Dipartimento di Biotecnologie e Bioscienze, Universita degli Studi di Milano Bicocca - piazza della Scienza 2--> , I-20126 Milano--> - ITALY...

  9. Korean Kimchi Chemistry: A Multicultural Chemistry Connection

    Science.gov (United States)

    Murfin, Brian

    2009-01-01

    Connecting science with different cultures is one way to interest students in science, to relate science to their lives, and at the same time to broaden their horizons in a variety of ways. In the lesson described here, students make kimchi, a delicious and popular Korean dish that can be used to explore many important chemistry concepts,…

  10. Young Children's Comprehension of Logical Connectives.

    Science.gov (United States)

    Suppes, Patrick; Feldman, Shirley

    To determine to what extent children of preschool age comprehend the meaning of logical connectives, 64 5- and 6-year-olds were told to hand differently colored and shaped wooden blocks to an experimenter. The commands involved various English idioms used for conjunction (e.g. both black and round), disjunction (either black or round), and…

  11. Economics and the Real-Life Connection.

    Science.gov (United States)

    Murphy, Sue; Walsh, Janet

    1989-01-01

    Discusses the connection between economics and decision making in everyday life. Compares basic economic concepts such as choices, scarcity, opportunity costs, indirect costs, and decision making to the choices that students make in their personal lives. Maintains that through the study of economics, students can become responsible decision…

  12. Emotions - connecting with the missing body

    DEFF Research Database (Denmark)

    Kristensen, Liv Kondrup; Otrel-Cass, Kathrin

    2015-01-01

    differences in behavior between people shape emotional responses. Merleau-Ponty’s theorization of the body and feelings are connected to embodiment, while examining central concepts such as consciousness and perception. Merleau-Ponty describes what he calls the emotional atmosphere and how it shapes the ways...

  13. HAJOS' CONJECTURE AND CONNECTIVITY OF EULERIAN GRAPHS

    Institute of Scientific and Technical Information of China (English)

    XU Baogang

    2002-01-01

    Hajós' conjecture asserts that a simple eulerian graph on n vertices can be decomposed into at most n-1/2 circuits. In this paper, we propose a new conjecture sufficient to prove this new conjecture for 3-connected graphs. Furthermore, a special 3-cut is considered also.

  14. Graph sharing games: complexity and connectivity

    CERN Document Server

    Cibulka, Josef; Mészáros, Viola; Stolař, Rudolf; Valtr, Pavel

    2012-01-01

    We study the following combinatorial game played by two players, Alice and Bob, which generalizes the Pizza game considered by Brown, Winkler and others. Given a connected graph G with nonnegative weights assigned to its vertices, the players alternately take one vertex of G in each turn. The first turn is Alice's. The vertices are to be taken according to one (or both) of the following two rules: (T) the subgraph of G induced by the taken vertices is connected during the whole game, (R) the subgraph of G induced by the remaining vertices is connected during the whole game. We show that if rules (T) and/or (R) are required then for every epsilon > 0 and for every positive integer k there is a k-connected graph G for which Bob has a strategy to obtain (1-epsilon) of the total weight of the vertices. This contrasts with the original Pizza game played on a cycle, where Alice is known to have a strategy to obtain 4/9 of the total weight. We show that the problem of deciding whether Alice has a winning strategy (i...

  15. Theory of Mind and Giftedness: New Connections

    Science.gov (United States)

    Walker, Cheryl L.; Shore, Bruce M.

    2011-01-01

    The social and cognitive phenomena associated with theory of mind (ToM) and research on the social and cognitive qualities of giftedness have not been sufficiently connected. The common focus areas for ToM researchers (e.g., false-belief understanding, deception, and autism) should be of interest to gifted education research because these are…

  16. Kähler Quantization and Hitchin Connections

    DEFF Research Database (Denmark)

    Leth Gammelgaard, Niels

    such deformation quantization, which uses Feynman graphs to encode the relevant differential operators. In particular, this yields an explicit formula for the Berezin-Toeplitz star product. For geometric quantization, we consider Andersen's generalization of Hitchin's projectively flat connection to a general...

  17. A synthesis for exactly 3-edge-connected graphs

    OpenAIRE

    Kingsford, Carl; Marçais, Guillaume

    2009-01-01

    A multigraph is exactly k-edge-connected if there are exactly k edge-disjoint paths between any pair of vertices. We characterize the class of exactly 3-edge-connected graphs, giving a synthesis involving two operations by which every exactly 3-edge-connected multigraph can be generated. Slightly modified syntheses give the planar exactly 3-edge-connected graphs and the exactly 3-edge-connected graphs with the fewest possible edges.

  18. Dynamic functional connectivity reveals altered variability in functional connectivity among patients with major depressive disorder.

    Science.gov (United States)

    Demirtaş, Murat; Tornador, Cristian; Falcón, Carles; López-Solà, Marina; Hernández-Ribas, Rosa; Pujol, Jesús; Menchón, José M; Ritter, Petra; Cardoner, Narcis; Soriano-Mas, Carles; Deco, Gustavo

    2016-08-01

    Resting-state fMRI (RS-fMRI) has become a useful tool to investigate the connectivity structure of mental health disorders. In the case of major depressive disorder (MDD), recent studies regarding the RS-fMRI have found abnormal connectivity in several regions of the brain, particularly in the default mode network (DMN). Thus, the relevance of the DMN to self-referential thoughts and ruminations has made the use of the resting-state approach particularly important for MDD. The majority of such research has relied on the grand averaged functional connectivity measures based on the temporal correlations between the BOLD time series of various brain regions. We, in our study, investigated the variations in the functional connectivity over time at global and local level using RS-fMRI BOLD time series of 27 MDD patients and 27 healthy control subjects. We found that global synchronization and temporal stability were significantly increased in the MDD patients. Furthermore, the participants with MDD showed significantly increased overall average (static) functional connectivity (sFC) but decreased variability of functional connectivity (vFC) within specific networks. Static FC increased to predominance among the regions pertaining to the default mode network (DMN), while the decreased variability of FC was observed in the connections between the DMN and the frontoparietal network. Hum Brain Mapp 37:2918-2930, 2016. © 2016 Wiley Periodicals, Inc. PMID:27120982

  19. Maximizing algebraic connectivity in air transportation networks

    Science.gov (United States)

    Wei, Peng

    In air transportation networks the robustness of a network regarding node and link failures is a key factor for its design. An experiment based on the real air transportation network is performed to show that the algebraic connectivity is a good measure for network robustness. Three optimization problems of algebraic connectivity maximization are then formulated in order to find the most robust network design under different constraints. The algebraic connectivity maximization problem with flight routes addition or deletion is first formulated. Three methods to optimize and analyze the network algebraic connectivity are proposed. The Modified Greedy Perturbation Algorithm (MGP) provides a sub-optimal solution in a fast iterative manner. The Weighted Tabu Search (WTS) is designed to offer a near optimal solution with longer running time. The relaxed semi-definite programming (SDP) is used to set a performance upper bound and three rounding techniques are discussed to find the feasible solution. The simulation results present the trade-off among the three methods. The case study on two air transportation networks of Virgin America and Southwest Airlines show that the developed methods can be applied in real world large scale networks. The algebraic connectivity maximization problem is extended by adding the leg number constraint, which considers the traveler's tolerance for the total connecting stops. The Binary Semi-Definite Programming (BSDP) with cutting plane method provides the optimal solution. The tabu search and 2-opt search heuristics can find the optimal solution in small scale networks and the near optimal solution in large scale networks. The third algebraic connectivity maximization problem with operating cost constraint is formulated. When the total operating cost budget is given, the number of the edges to be added is not fixed. Each edge weight needs to be calculated instead of being pre-determined. It is illustrated that the edge addition and the

  20. Brain connectivity in pathological and pharmacological coma

    Directory of Open Access Journals (Sweden)

    Quentin Noirhomme

    2010-12-01

    Full Text Available Recent studies in patients with disorders of consciousness (DOC tend to support the view that awareness is not related to activity in a single brain region but to thalamo-cortical connectivity in the frontoparietal network. Functional neuroimaging studies have shown preserved albeit disconnected low level cortical activation in response to external stimulation in patients in a vegetative state or unresponsive wakefulness syndrome. While activation of these primary sensory cortices does not necessarily reflect conscious awareness, activation in higher order associative cortices in minimally conscious state patients seems to herald some residual perceptual awareness. PET studies have identified a metabolic dysfunction in a widespread fronto-parietal global neuronal workspace in DOC patients including the midline default mode network, ‘intrinsic’ system, and the lateral frontoparietal cortices or ‘extrinsic system’. Recent studies have investigated the relation of awareness to the functional connectivity within intrinsic and extrinsic networks, and with the thalami in both pathological and pharmacological coma. In brain damaged patients, connectivity in all default network areas was found to be non-linearly correlated with the degree of clinical consciousness impairment, ranging from healthy controls and locked-in syndrome to minimally conscious, vegetative, coma and brain dead patients. Anesthesia-induced loss of consciousness was also shown to correlate with a global decrease in cortico-cortical and thalamo-cortical connectivity in both intrinsic and extrinsic networks, but not in auditory or visual networks. In anesthesia, unconsciousness was also associated with a loss of cross-modal interactions between networks. These results suggest that conscious awareness critically depends on the functional integrity of thalamo-cortical and cortico-cortical frontoparietal connectivity within and between intrinsic and extrinsic brain networks.

  1. The functional connectivity of the human caudate: An application of meta-analytic connectivity modeling with behavioral filtering

    OpenAIRE

    Robinson, Jennifer L.; Laird, Angela R.; Glahn, David C.; Blangero, John; Sanghera, Manjit K.; Pessoa, Luiz; Fox, P. Mickle; Uecker, Angela; Friehs, Gerhard; Young, Keith A.; Griffin, Jennifer L.; LOVALLO, WILLIAM R.; Fox, Peter T

    2011-01-01

    Meta-analysis based techniques are emerging as powerful, robust tools for developing models of connectivity in functional neuroimaging. Here, we apply meta-analytic connectivity modeling to the human caudate to 1) develop a model of functional connectivity, 2) determine if meta-analytic methods are sufficiently sensitive to detect behavioral domain specificity within region-specific functional connectivity networks, and 3) compare meta-analytic driven segmentation to structural connectivity p...

  2. The Washington Connected Landscapes Project: Providing Analysis Tools for Regional Connectivity and Climate Adaptation Planning

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project builds on existing work by the Washington Habitat Connectivity Working Group to provide scientific analyses and tools necessary to conserve wildlife...

  3. Connect Global Positioning System RF Module

    Science.gov (United States)

    Franklin, Garth W.; Young, Lawrence E.; Ciminera, Michael A.; Tien, Jeffrey Y.; Gorelik, Jacob; Okihiro, Brian Bachman; Koelewyn, Cynthia L.

    2012-01-01

    The CoNNeCT Global Positioning System RF Module (GPSM) slice is part of the JPL CoNNeCT Software Defined Radio (SDR). CoNNeCT is the Communications, Navigation, and Net working reconfigurable Testbed project that is part of NASA's Space Communication and Nav igation (SCaN) Program. The CoNNeCT project is an experimental dem onstration that will lead to the advancement of SDRs and provide a path for new space communication and navigation systems for future NASA exploration missions. The JPL CoNNeCT SDR will be flying on the International Space Station (ISS) in 2012 in support of the SCaN CoNNeCT program. The GPSM is a radio-frequency sampler module (see Figure 1) that directly sub-harmonically samples the filtered GPS L-band signals at L1 (1575.42 MHz), L2 (1227.6 MHz), and L5 (1176.45 MHz). The JPL SDR receives GPS signals through a Dorne & Margolin antenna mounted onto a choke ring. The GPS signal is filtered against interference, amplified, split, and fed into three channels: L1, L2, and L5. In each of the L-band channels, there is a chain of bandpass filters and amplifiers, and the signal is fed through each of these channels to where the GPSM performs a one-bit analog-to-digital conversion (see Figure 2). The GPSM uses a sub-harmonic, single-bit L1, L2, and L5 sampler that samples at a clock rate of 38.656 MHz. The new capability is the down-conversion and sampling of the L5 signal when previous hardware did not provide this capability. The first GPS IIF Satellite was launched in 2010, providing the new L5 signal. With the JPL SDR flying on the ISS, it will be possible to demonstrate navigation solutions with 10-meter 3-D accuracy at 10-second intervals using a field-program mable gate array (FPGA)-based feedback loop running at 50 Hz. The GPS data bits will be decoded and used in the SDR. The GPSM will also allow other waveforms that are installed in the SDR to demonstrate various GNSS tracking techniques.

  4. Connecting RDA and RDF: Linked Data for a Wide World of Connected Possibilities

    OpenAIRE

    Ashleigh Faith; Michelle Chrzanowski

    2015-01-01

    Libraries have struggled with connecting a plethora of content and the metadata stored in catalogs to patrons. Adding more value to catalogs, more tools for reference librarians, and enriched patron search, linked data is a means to connect more people with more relevant information. With the recent transition to the Resource Description and Access (RDA) cataloging standard within libraries, linking data in library databases has become a much easier project to tackle, largely because of anoth...

  5. Geological connectivity drives microbial community structure and connectivity in polar, terrestrial ecosystems.

    Science.gov (United States)

    Ferrari, Belinda C; Bissett, Andrew; Snape, Ian; van Dorst, Josie; Palmer, Anne S; Ji, Mukan; Siciliano, Steven D; Stark, Jonathon S; Winsley, Tristrom; Brown, Mark V

    2016-06-01

    Landscape heterogeneity impacts community assembly in animals and plants, but it is not clear if this ecological concept extends to microbes. To examine this question, we chose to investigate polar soil environments from the Antarctic and Arctic, where microbes often form the major component of biomass. We examined soil environments that ranged in connectivity from relatively well-connected slopes to patchy, fragmented landforms that comprised isolated frost boils. We found landscape connectedness to have a significant correlation with microbial community structure and connectivity, as measured by co-occurrence networks. Soils from within fragmented landforms appeared to exhibit less local environmental heterogeneity, harboured more similar communities, but fewer biological associations than connected landforms. This effect was observed at both poles, despite the geographical distances and ecological differences between them. We suggest that microbial communities inhabiting well-connected landscape elements respond consistently to regional-scale gradients in biotic and edaphic factors. Conversely, the repeated freeze thaw cycles that characterize fragmented landscapes create barriers within the landscape and act to homogenize the soil environment within individual frost boils and consequently the microbial communities. We propose that lower microbial connectivity in the fragmented landforms is a function of smaller patch size and continual disturbances following soil mixing. PMID:26310523

  6. The effect of connectives on the selection of arguments: implicit consequentiality bias for the connective "but".

    Science.gov (United States)

    Rigalleau, François; Guerry, Michèle; Granjon, Lionel

    2014-08-01

    Recent studies about the implicit causality of inter-personal verbs showed a symmetric implicit consequentiality bias for psychological verbs. This symmetry is less clear for action verbs because the verbs assigning the implicit cause to the object argument (e.g. "Peter protected John because he was in danger.") tend to assign the implicit consequence to the same argument (e.g. "Peter protected John so he was not hurt."). We replicated this result by comparing continuations of inter-personal events followed by a causal connective "because" or a consequence connective "so". Moreover, we found similar results when the consequence connective was replaced by a contrastive connective "but". This result was confirmed in a second experiment where we measured the time required to imagine a consistent continuation for a fragment finishing with "but s/he ...". The results were consistent with a contrastive connective introducing a denial of a consequence of the previous event. The results were consistent with a model suggesting that thematic roles and connectives can predict preferred co-reference relations. PMID:23982891

  7. Sociology: a lost connection in social psychology.

    Science.gov (United States)

    Oishi, Shigehiro; Kesebir, Selin; Snyder, Benjamin H

    2009-11-01

    For the first half of the 20th century, sociology was one of the closest allies of social psychology. Over the past four decades, however, the connection with sociology has weakened, whereas new connections with neighboring disciplines (e.g., biology, economics, political science) have formed. Along the way, the sociological perspective has been largely lost in mainstream social psychology in the United States. Most social psychologists today are not concerned with collective phenomena and do not investigate social structural factors (e.g., residential mobility, socioeconomic status, dominant religion, political systems). Even when the social structural factors are included in the analysis, psychologists typically treat them as individual difference variables. Sociologist C. Wright Mills famously promoted sociological imagination, or the ability to see distal yet important social forces operating in a larger societal context. By comparing sociological perspectives to psychological perspectives, this article highlights the insights that the sociological perspective and sociological imagination can bring to social psychology.

  8. STATIONARY CONNECTED CURVES IN HILBERT SPACES

    Directory of Open Access Journals (Sweden)

    Raed Hatamleh

    2014-01-01

    Full Text Available In this article the structure of non-stationary curves which are stationary connected in Hilbert space is studied using triangular models of non-self-adjoint operator. The concept of evolutionary representability plays here an important role. It is proved that if one of two curves in Hilbert space is evolutionary representable and the curves are stationary connected, then another curve is evolutionary representable too. These curves are studied firstly. The structure of a cross-correlation function in the case when operator, defining the evolutionary representation, has one-dimensional non-Hermitian subspace (the spectrum is discreet and situated in the upper complex half-plane or has infinite multiplicity at zero (Volterra operator is studied.

  9. Blade couple with dry friction connection

    Directory of Open Access Journals (Sweden)

    Půst L.

    2015-06-01

    Full Text Available Vibration of a blade couple damped by a dry friction contact in the shroud is investigated by means of hysteresis loops and response curves analysis. The studied system is excited by one harmonic external force in a frequency range near to the lowest eigenfrequency of real blades. Blades are connected by means of a damping element consisting of dry friction part linked in series with linear spring. This "stick-slip" damping element is supposed to be either weightless or of a very small mass which models the mass of elastically deformed parts of contacting bodies near the friction surface. Two approximate mathematical models of "stick-slip" dry friction elements are suggested and analysed. The response curves of blade couple connected by stick-slip damping element are presented for different values of slip friction forces and two values of mass of elastically deformed parts.

  10. Advanced connection systems for architectural glazing

    CERN Document Server

    Afghani Khoraskani, Roham

    2015-01-01

    This book presents the findings of a detailed study to explore the behavior of architectural glazing systems during and after an earthquake and to develop design proposals that will mitigate or even eliminate the damage inflicted on these systems. The seismic behavior of common types of architectural glazing systems are investigated and causes of damage to each system, identified. Furthermore, depending on the geometrical and structural characteristics, the ultimate horizontal load capacity of glass curtain wall systems is defined based on the stability of the glass components. Detailed attention is devoted to the incorporation of advanced connection devices between the structure of the building and the building envelope system in order to minimize the damage to glazed components. An innovative new connection device is introduced that results in a delicate and functional system easily incorporated into different architectural glazing systems, including those demanding maximum transparency.

  11. Connectivity editing for quad-dominant meshes

    KAUST Repository

    Peng, Chihan

    2013-08-01

    We propose a connectivity editing framework for quad-dominant meshes. In our framework, the user can edit the mesh connectivity to control the location, type, and number of irregular vertices (with more or fewer than four neighbors) and irregular faces (non-quads). We provide a theoretical analysis of the problem, discuss what edits are possible and impossible, and describe how to implement an editing framework that realizes all possible editing operations. In the results, we show example edits and illustrate the advantages and disadvantages of different strategies for quad-dominant mesh design. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and John Wiley & Sons Ltd.

  12. Modified Eccentric Connectivity of Generalized Thorn Graphs

    Directory of Open Access Journals (Sweden)

    Nilanjan De

    2014-01-01

    Full Text Available The thorn graph GT of a given graph G is obtained by attaching t(>0 pendent vertices to each vertex of G. The pendent edges, called thorns of GT, can be treated as P2 or K2, so that a thorn graph is generalized by replacing P2 by Pm and K2 by Kp and the respective generalizations are denoted by GPm and GKp. The modified eccentric connectivity index of a graph is defined as the sum of the products of eccentricity with the total degree of neighboring vertices, over all vertices of the graph in a hydrogen suppressed molecular structure. In this paper, we give the modified eccentric connectivity index and the concerned polynomial for the thorn graph GT and the generalized thorn graphs GKp and GPm.

  13. FEMINISM AND COSMOPOLITANISM: SOME INEVITABLE CONNECTIONS

    Directory of Open Access Journals (Sweden)

    Diana Elena NEAGA

    2011-08-01

    Full Text Available In this paper I will approach the issue of feminism and cosmopolitanism in order to give arguments in sustaining the fact that, today, feminism and cosmopolitanism are inevitable connected. In constructing my discourse I will begin by laying out the main ideas of cosmopolitanism, followed by a presentation of the construction of the feminist movement over time, inter-relating these two discourses at the end of the analysis. Connected with political ethics, political theory and political philosophy, the theoretical framework selected for this paper is based on the cosmopolitan theory developed by scholars like Martha Nussbaum, Fiona Robinson and Kwame Anthony Appaih who, underlining universality, define cosmopolitism as a universal concern with every human life and its well-being, but who are also giving value to the differences (seen as cultural or/ and of identity insofar as they are not harmful to people.

  14. Fiber-connected position localization sensor networks

    Science.gov (United States)

    Pan, Shilong; Zhu, Dan; Fu, Jianbin; Yao, Tingfeng

    2014-11-01

    Position localization has drawn great attention due to its wide applications in radars, sonars, electronic warfare, wireless communications and so on. Photonic approaches to realize position localization can achieve high-resolution, which also provides the possibility to move the signal processing from each sensor node to the central station, thanks to the low loss, immunity to electromagnetic interference (EMI) and broad bandwidth brought by the photonic technologies. In this paper, we present a review on the recent works of position localization based on photonic technologies. A fiber-connected ultra-wideband (UWB) sensor network using optical time-division multiplexing (OTDM) is proposed to realize high-resolution localization and moving the signal processing to the central station. A 3.9-cm high spatial resolution is achieved. A wavelength-division multiplexed (WDM) fiber-connected sensor network is also demonstrated to realize location which is independent of the received signal format.

  15. Sentence structures with the connective verbs

    Directory of Open Access Journals (Sweden)

    Ružić Vladislava

    2006-01-01

    Full Text Available This paper talks about specific sentence structures in contemporary Serbian language that are a transition between simple and complex sentences, since they contain two finite forms of the verbs (e.g. To je da poludiš; Smisao pravde leži u tome da krivci budu kažnjeni, that however are a functionally - semantically unique predicate only when occurring together. At the position of the second part of the predicate phrase, there is a clause with a subordinate conjunction as its semantic core. Some types of the connective verbs are described, which have a specific role to connect subject argument and its related content or to mark the content of the sentence with a specific modality.

  16. Functional connectivity metrics during stroke recovery

    DEFF Research Database (Denmark)

    Yourganov, Grigori; Schmah, Tanya; Small, Steven L.;

    2010-01-01

    We explore functional connectivity in nine subjects measured with 1 5T fMRI-BOLD in a longitudinal study of recovery from unilateral stroke affecting the motor area (Small et al, 2002) We found that several measures of complexity of covariance matrices show strong correlations with behavioral...... that potentially important differences in functional connectivity exist between the early and late sessions Motivated by McIntosh et al (2008), who showed that EEG brain-signal variability and behavioral performance both increased with age during development, we investigated complexity of the covariance matrix...... for this longitudinal stroke recovery data set We used three complexity measures the sphericity index described by Abdi (2010), "unsupervised dimensionality", which is the number of PCs that minimizes unsupervised generalization error of a covariance matrix (Hansen et al, 1999), and "QD dimensionality", which...

  17. Painful connections: densification versus fibrosis of fascia.

    Science.gov (United States)

    Pavan, Piero G; Stecco, Antonio; Stern, Robert; Stecco, Carla

    2014-01-01

    Deep fascia has long been considered a source of pain, secondary to nerve pain receptors becoming enmeshed within the pathological changes to which fascia are subject. Densification and fibrosis are among such changes. They can modify the mechanical properties of deep fasciae and damage the function of underlying muscles or organs. Distinguishing between these two different changes in fascia, and understanding the connective tissue matrix within fascia, together with the mechanical forces involved, will make it possible to assign more specific treatment modalities to relieve chronic pain syndromes. This review provides an overall description of deep fasciae and the mechanical properties in order to identify the various alterations that can lead to pain. Diet, exercise, and overuse syndromes are able to modify the viscosity of loose connective tissue within fascia, causing densification, an alteration that is easily reversible. Trauma, surgery, diabetes, and aging alter the fibrous layers of fasciae, leading to fascial fibrosis.

  18. Modifying network connectivity with a subgraph addition

    CERN Document Server

    Taylor, Dane

    2011-01-01

    The principal eigenvalue $\\lambda$ of a network's adjacency matrix often determines dynamics on the network (e.g., in synchronization and spreading processes) and some of its structural properties (e.g., robustness against failure or attack), and is therefore a good indicator for how "strongly" a network is connected. We study how $\\lambda$ is modified by the addition of a subgraph. This type of modification has broad applications, ranging from those involving a single modification (e.g., introduction of a drug into a biological process) to those involving repeated subnetwork additions (e.g., power-grid and transit development). We describe how to optimally connect the subgraph to the network to either maximize or minimize the shift in $\\lambda$, noting several applications.

  19. FEMINISM AND COSMOPOLITANISM: SOME INEVITABLE CONNECTIONS

    Directory of Open Access Journals (Sweden)

    DIANA ELENA NEAGA

    2011-04-01

    Full Text Available In this paper I will approach the issue of feminism and cosmopolitanism in order to give arguments in sustaining the fact that, today, feminism and cosmopolitanism are inevitable connected. In constructing my discourse I will begin by laying out the main ideas of cosmopolitanism, followed by a presentation of the construction of the feminist movement over time, inter-relating these two discourses at the end of the analysis. Connected with political ethics, political theory and political philosophy, the theoretical framework selected for this paper is based on the cosmopolitan theory developed by scholars like Martha Nussbaum, Fiona Robinson and Kwame Anthony Appaih who, underlining universality, define cosmopolitism as a universal concern with every human life and its well-being, but who are also giving value to the differences (seen as cultural or/ and of identity insofar as they are not harmful to people.

  20. Autodesk发布Inventor Connected Design

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    2015年12月,欧特克公司宣布针对Inventor维护合约用户推出新的协作工具Inventor Connected Design.Inventor Connected Design将Inventor连入云端运算平台,用户可透过AutodeskA360,轻易地在Inventor中进行“设计分享协作会议”,进行设计标注,辅助、推动和记录设计决策的过程,同时管理设计的各项资源.通过云端,多个工程团队可跨越产品开发工作流程开展协作,加快决策流程.

  1. Characterization of damped structural connections for multi-component systems

    Science.gov (United States)

    Lawrence, Charles; Huckelbridge, Arthur A.

    1989-01-01

    The inability to model connections adequately has historically limited the ability to predict overall system dynamic response. Connections between structural components are often mechanically complex and difficult to accurataely model analytically. Improved analytical models for connections are needed to improve system dynamic predictions. This study explores combining Component Mode Synthesis methods for coupling structural components with Parameter Identification procedures for improving the analytical modeling of the connections. Improvements in the connection stiffness and damping properties are computed in terms of physical parameters so the physical characteristics of the connections can be better understood, in addition to providing improved input for the system model.

  2. The Internet of things connecting objects

    CERN Document Server

    Chaouchi, Hakima

    2013-01-01

    Internet of Things: Connecting Objects… puts forward the technologies and the networking architectures which make it possible to support the Internet of Things. Amongst these technologies, RFID, sensor and PLC technologies are described and a clear view on how they enable the Internet of Things is given. This book also provides a good overview of the main issues facing the Internet of Things such as the issues of privacy and security, application and usage, and standardization.

  3. Connection between Interception and Political Scene

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>Interception can shake Murdoch’s the News Corporation;can also make the president of a country quit the political scene;even can trigger a coup.There’s no exaggeration. Only knowing yourself as well as the enemy,then you can fight a hundred battles with no danger of defeat. But how can one know the enemy? Interception is the most powerful tool. It is doomed to have connection with political scene ever since its birth.

  4. Supernovae and gamma-ray bursts connection

    Science.gov (United States)

    Valle, Massimo Della

    2015-12-01

    I'll review the status of the Supernova/Gamma-Ray Burst connection. Several pieces of evidence suggest that long duration Gamma-ray Bursts are associated with bright SNe-Ic. However recent works suggest that GRBs might be produced in tight binary systems composed of a massive carbon-oxygen cores and a neutron star companion. Current estimates of the SN and GRB rates yield a ratio GRB/SNe-Ibc in the range ˜ 0.4% - 3%.

  5. Linear Algorithm for Digital Euclidean Connected Skeleton

    OpenAIRE

    Leborgne, Aurélie; Mille, Julien; Tougne, Laure

    2013-01-01

    The skeleton is an essential shape characteristic providing a compact representation of the studied shape. Its computation on the image grid raises many issues. Due to the effects of discretization, the required properties of the skeleton - thinness, homotopy to the shape, reversibility, connectivity - may become incompatible. However, as regards practical use, the choice of a specific skeletonization algorithm depends on the application. This allows to classify the desired properties by orde...

  6. Living Autoethnography: Connecting Life and Research

    OpenAIRE

    Faith Wambura Ngunjiri; Kathy-Ann C. Hernandez; Heewon Chang

    2010-01-01

    Autoethnography is a qualitative research method that utilizes data about self and context to gain an understanding of the connectivity between self and others. This introductory article exposes the reader to our own praxis of collaborative autoethnography which we used to interrogate how we navigate the US academy as immigrant women faculty. Before introducing the articles in this special issue, we explore the autoethnography continuum, provide sample areas covered by autoethnographers, and ...

  7. Gender Differences in Brain Functional Connectivity Density

    OpenAIRE

    Tomasi, Dardo; Volkow, Nora D

    2011-01-01

    The neural bases of gender differences in emotional, cognitive, and socials behaviors are largely unknown. Here, magnetic resonance imaging data from 336 women and 225 men revealed a gender dimorphism in the functional organization of the brain. Consistently across five research sites, women had 14% higher local functional connectivity density (lFCD) and up to 5% higher gray matter density than men in cortical and subcortical regions. The negative power scaling of the lFCD was steeper for men...

  8. THE DEVELOPMENT OF BRAIN STRUCTURE AND CONNECTIVITY

    OpenAIRE

    Wierenga, L.M.

    2016-01-01

    The human brain undergoes profound structural changes with development. It does not mature by simply growing, rather the transition to adulthood is a dynamic process with regionally specific patterns. However, there is no consensus on the timing and shape of growth trajectories of brain structures. In this thesis we capitalize on advances in multimodal MRI and use longitudinal study designs to map structural brain maturation and connectivity in typical and atypical children and adolescents. O...

  9. Connecting strangers at a train station

    DEFF Research Database (Denmark)

    Serafin, Stefania; Böttcher, Niels; Pellarin, Lars;

    2005-01-01

    In this paper we describe a virtual instrument or a performance space, placed at Høje Tåstrup train station in Denmark, which is meant to establish communicative connections between strangers, by letting users of the system create soundscapes together across the rails. We discuss mapping...... to the development of an interactive installation which takes place in Hoje Taastrup train station in Denmark....

  10. Supernovae and gamma-ray bursts connection

    Energy Technology Data Exchange (ETDEWEB)

    Valle, Massimo Della [INAF-Napoli, Capodimonte Observatory, Salita Moiariello, 16, I-80131 Napoli (Italy); International Center for Relativistic Astrophysics Network, Piazzale della Repubblica 10, I-65122, Pescara (Italy)

    2015-12-17

    I’ll review the status of the Supernova/Gamma-Ray Burst connection. Several pieces of evidence suggest that long duration Gamma-ray Bursts are associated with bright SNe-Ic. However recent works suggest that GRBs might be produced in tight binary systems composed of a massive carbon-oxygen cores and a neutron star companion. Current estimates of the SN and GRB rates yield a ratio GRB/SNe-Ibc in the range ∼ 0.4% − 3%.

  11. Careers, Connections and Corruption Risks in Europe

    DEFF Research Database (Denmark)

    Charron, Nicholas; Dahlström, Carl; Fazekas, Mihály;

    the interplay between politics and bureaucracy. It suggests that corruption risks are minimized when the two groups involved in decision-making on public contracts—politicians and bureau-crats—have known different interests. This is institutionalized when politicians are accountable to the electorate, while.......4 million procurement contracts. Both show a remarkable sub-national variation across Europe. The study finds corruption risks significantly lower where bureau-crats’ careers do not depend on political connections....

  12. A causally connected superluminal Warp Drive spacetime

    OpenAIRE

    Loup, F.; Held, R.; Waite, D; Halerewicz, Jr., E.; Stabno, M.; Kuntzman, M.; Sims, R.

    2002-01-01

    It will be shown that while horizons do not exist for warp drive spacetimes traveling at subluminal velocities horizons begin to develop when a warp drive spacetime reaches luminal velocities. However it will be shown that the control region of a warp drive ship lie within the portion of the warped region that is still causally connected to the ship even at superluminal velocities, therefore allowing a ship to slow to subluminal velocities. Further it is shown that the warped regions which ar...

  13. Parts of the Whole: Only Connect

    OpenAIRE

    Dorothy Wallace

    2014-01-01

    This is the first of several columns that will focus on the mechanisms by which new ideas become accepted by a culture, offering some familiar examples, deriving basic principles from these examples, and applying them to the problem of promoting quantitative literacy in an educational system. In this essay we describe how new concepts become embedded in a culture through their connections to existing ideas, and use this principle to suggest strategies of discourse about numeracy that promote ...

  14. Halotools: Galaxy-Halo connection models

    Science.gov (United States)

    Hearin, Andrew; Tollerud, Erik; Robitaille, Thomas; Droettboom, Michael; Zentner, Andrew; Bray, Erik; Craig, Matt; Bradley, Larry; Barbary, Kyle; Deil, Christoph; Tan, Kevin; Becker, Matthew R.; More, Surhud; Günther, Hans Moritz; Sipocz, Brigitta

    2016-04-01

    Halotools builds and tests models of the galaxy-halo connection and analyzes catalogs of dark matter halos. The core functions of the package include fast generation of synthetic galaxy populations using HODs, abundance matching, and related methods; efficient algorithms for calculating galaxy clustering, lensing, z-space distortions, and other astronomical statistics; a modular, object-oriented framework for designing galaxy evolution models; and end-to-end support for reducing halo catalogs and caching them as hdf5 files.

  15. Pipeline to connect Bratislava and Vienna

    International Nuclear Information System (INIS)

    A connection will be built to connect pipeline Druzba and OMV refinery in Schwechat close to Vienna. This is the conclusion of a Memorandum of Understanding signed by Chairman of Board of Directors of OMV, Wolfgang Ruttenstorfer and the First Vice-President for Marketing in Jukos, Michail Brudno in Vienna last week. The sixty-kilometres long pipeline should be completed in 2005. First oil from western Siberia should flow into Austria in 2006. OMV signed a ten-years contract for 2 million tons of oil per year. This volume represents about 20 percent of the total capacity of the refinery in Schwechat. 'For us this is a price-effective solution. The transport will be cheaper,' said Vice-Chairman of Board of Directors of OMV, Gerhard Roiss. OMV plans to expand in the central-European region and to increase its current number of petrol-stations from the current 1.600 to 2.000 by 2008. Starting capacity of the pipeline will be 3.6 million tons that can be increased to 5 million tons. In Austria the pipeline will be operated by a new joint company where 26 percent will be controlled by OMV and 74 by Jukos or 'structures connected to Jukos'. The total investment related to connection of Druzba and the Austrian refinery should be about 28 million Euro (1.2 billion Slovak crowns). Investments in Slovakia should reach about 7.5 million Euro (314 million Slovak crowns). A major part of these cost should be covered by Jukos. The Slovak part will owned and operated by Transpetrol, a.s., Bratislava that operates and owns all the pipelines in Slovakia

  16. Emotional signals in connection with body language.

    OpenAIRE

    Škoda, Jakub

    2014-01-01

    The thesis deals with emotional expressions in body language and its interpretation. In the theoretical part, the author deals with emotions and theories focused on emotions, sympathy, verbal and nonverbal communication as well as body language (gestures, facial expressions, body types and attractiveness). There are many books which provide information about how to recognize nonverbal signals in communication. This study tries to find out if there is a connection between experiences gathered ...

  17. Emerging connections in the ethylene signaling network

    OpenAIRE

    Yoo, Sang-Dong; Cho, Younghee; Sheen, Jen

    2009-01-01

    The gaseous plant hormone ethylene acts as a pivotal mediator to respond to and coordinate internal and external cues in modulating plant growth dynamics and developmental programs. Genetic analysis of Arabidopsis thaliana has been used to identify key components and to build a linear ethylene-signaling pathway from the receptors through to the nuclear transcription factors. Studies applying integrative approaches have revealed new regulators, molecular connections and mechanisms in ethylene ...

  18. MIXED CONNECTIVE TISSUE DISORDER WITH PREGNANCY

    OpenAIRE

    Narmadha; Jamila; Abhinaya; Vivek

    2015-01-01

    Mixed connective tissue disease (MCTD) is a term involving the features of lupus systemic sclerosis, polymyositis, rheumatoid arthritis and high titre of anti ribonucleoprotein (RNP) antibodies, exact etiology is not known. It is characterized by microvascular damage, immune system activation leading to inflammation and excessive deposition of collagen in the skin, lungs, heart, gastrointestinal tract and kidneys. The females are being more affected especially after childbirth...

  19. Emulex下一代OneConnect UCNA

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Emulex公司日前宣布,其基于BladeEngine3(BE3)10Gb/s以太网(1OGbE)I/O控制器(IOC)的OneConnect OCe11000系列通用聚合网络适配器(UCNA)的最新产品全面上市。BE3是一款单芯片、双端口的IOGbE IOC。

  20. ABR Flow Control for Multipoint Connections

    OpenAIRE

    Fahmy, Sonia; Jain, Raj

    1998-01-01

    Multipoint capabilities are essential for ATM networks to efficiently support many applications, including IP multicasting and overlay applications. The current signaling and routing specifications for ATM define point-to-multipoint capabilities. Multipoint-to-point connection support is also being discussed by the signaling and PNNI groups, and will be defined in the near future for the unspecified bit rate (UBR) service. We examine point-to-multipoint and multipoint-to-point flow control fo...

  1. HAJOS‘ CONJECTURE AND CONNECTIVITY OF EULERIAN GRAPHS

    Institute of Scientific and Technical Information of China (English)

    XUBaogang

    2002-01-01

    Hajos' conjecture asserts that a simple eulerian graph on n vertices can be decomposed into at most n-1/2 circuits,In this paper,we propose a new conjecture which is equivalent to Hajos' conjecture.and show that to prove Hajos' conjecture,it is sufficent to prove this new conjecture for 3-connected graphs.Furthermore,a special 3-cut is considered also.

  2. Connecting care competencies and culture during disasters

    Directory of Open Access Journals (Sweden)

    Chhabra Vivek

    2009-01-01

    Full Text Available Connecting care Competencies and Culture are core fundamentals in responding to disasters. Thick coordination between professionals, communities and agencies in different geographical areas is crucial to the happening of appropriate preparedness and thus efficient response and mitigation of a disaster. In the next few articles, we present diverse examples related to the preparedness and recovery process to adverse disasters across the globe

  3. Maximizing algebraic connectivity in interconnected networks.

    Science.gov (United States)

    Shakeri, Heman; Albin, Nathan; Darabi Sahneh, Faryad; Poggi-Corradini, Pietro; Scoglio, Caterina

    2016-03-01

    Algebraic connectivity, the second eigenvalue of the Laplacian matrix, is a measure of node and link connectivity on networks. When studying interconnected networks it is useful to consider a multiplex model, where the component networks operate together with interlayer links among them. In order to have a well-connected multilayer structure, it is necessary to optimally design these interlayer links considering realistic constraints. In this work, we solve the problem of finding an optimal weight distribution for one-to-one interlayer links under budget constraint. We show that for the special multiplex configurations with identical layers, the uniform weight distribution is always optimal. On the other hand, when the two layers are arbitrary, increasing the budget reveals the existence of two different regimes. Up to a certain threshold budget, the second eigenvalue of the supra-Laplacian is simple, the optimal weight distribution is uniform, and the Fiedler vector is constant on each layer. Increasing the budget past the threshold, the optimal weight distribution can be nonuniform. The interesting consequence of this result is that there is no need to solve the optimization problem when the available budget is less than the threshold, which can be easily found analytically. PMID:27078276

  4. Connection Cryostats for LHC Dispersion Suppressors

    CERN Document Server

    Marque, S; Genet, M; Skoczen, B

    2004-01-01

    The lattice of the Large Hadron Collider (LHC) being built at CERN is based on 8 standard arcs of 2.5 km length. Each arc is bounded on either side by Dispersion Suppressors connected to the arc by connection cryostats providing 15m long drift spaces. As for a dipole magnet, the connection cryostat provides a continuity of beam and insulation vacuum, electrical powering, cryogenic circuits, thermal and radiation shielding. In total 16 modules will be constructed. The stringent functional specification has led to various design options. Among them, a light mechanical structure has been developed with a stiffness comparable to that of a dipole magnet, for alignment purpose. Thermal studies, including lambda front propagation, have been performed to ensure a cooling down time to 1.9 K within the time budget. A special cooling scheme around the beam tubes has been chosen to cope with heat loads produced during operation. We report on the general design of these modules and on the adopted manufacturing process whi...

  5. Connected formulas for amplitudes in standard model

    CERN Document Server

    He, Song

    2016-01-01

    Witten's twistor string theory has led to new representations of S-matrix in massless QFT as a single object, including Cachazo-He-Yuan formulas in general and connected formulas in four dimensions. As a first step towards more realistic processes of the standard model, we extend the construction to QCD tree amplitudes with massless quarks and those with a Higgs boson. For both cases, we find connected formulas in four dimensions for all multiplicities which are very similar to the one for Yang-Mills amplitudes. The formula for quark-gluon color-ordered amplitudes differs from the pure-gluon case only by a Jacobian factor that depends on flavors and orderings of the quarks. In the formula for Higgs plus multi-parton amplitudes, the massive Higgs boson is effectively described by two additional massless legs which do not appear in the Parke-Taylor factor. The latter also represents the first twistor-string/connected formula for form factors.

  6. Modeling vertical coral connectivity and mesophotic refugia

    Science.gov (United States)

    Holstein, Daniel M.; Paris, Claire B.; Vaz, Ana C.; Smith, Tyler B.

    2016-03-01

    Whether mesophotic reefs will behave as refugia for corals threatened by global climate change and coastal development depends on vertical exchange of larvae between diverse habitats. Here we use a biophysical model of larval dispersal to estimate vertical connectivity of a broadcasting ( Orbicella faveolata) and a brooding ( Porites astreoides) species of coral in the US Virgin Islands. Modeling predicts subsidy to shallow areas by mesophotic larvae of both species based on local hydrology, adult reproductive characteristics, larval traits, and a wide range of scenarios developed to test depth-sensitive factors, such as fertilization rates and post-settlement survivorship. In extreme model scenarios of reduced fertilization and post-settlement survivorship of mesophotic larvae, 1-10 % local mesophotic subsidy to shallow recruitment is predicted for both species, which are demographically significant. Although direct vertical connectivity is higher for the broadcaster, the brooder demonstrates higher local multigenerational vertical connectivity, which suggests that local P. astreoides populations are more resilient than those of O. faveolata, and corroborates field studies. As shallow habitat degrades, mesophotic-shallow subsidy is predicted to increase for both species. This study is the first of its kind to simulate larval dispersal and settlement between habitats of different depths, and these findings have local, regional, and global implications for predicting and managing coral reef persistence in a changing climate.

  7. Exploring brain function from anatomical connectivity

    Directory of Open Access Journals (Sweden)

    Gorka eZamora-López

    2011-06-01

    Full Text Available The intrinsic relationship between the architecture of the brain and the range of sensory and behavioral phenomena it produces is a relevant question in neuroscience. Here, we review recent knowledge gained on the architecture of the anatomical connectivity by means of complex network analysis. It has been found that corticocortical networks display a few prominent characteristics: (i modular organization, (ii abundant alternative processing paths and (iii the presence of highly connected hubs. Additionally, we present a novel classification of cortical areas of the cat according to the role they play in multisensory connectivity. All these properties represent an ideal anatomical substrate supporting rich dynamical behaviors, as-well-as facilitating the capacity of the brain to process sensory information of different modalities segregated and to integrate them towards a comprehensive perception of the real world. The result here exposed are mainly based in anatomical data of cats’ brain, but we show how further observations suggest that, from worms to humans, the nervous system of all animals might share fundamental principles of organization.

  8. 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.

  9. The connection revisited; De aansluiting revisited

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, J.E.

    2009-10-15

    A previous article of this journal (NTE 2006, no 5, pp 155-164) was dedicated to the connection in the Dutch Electricity Act 1998. Since then there have been several amendments in regulation, decisions and jurisprudence to justify a follow-up article. This article aims to provide a thematic overview of the developments in Dutch regulation, NMa decisions and jurisprudence with regard to electricity and gas connection in the last three years, linking up to the themes addresses in the above-mentioned article. The focus is broadened to connections under the Electricity Act and the Gas Act. [Dutch] In een vorig artikel van dit tijdschrift (NTE 2006, no. 5, p. 155-164) is aandacht besteed aan de aansluiting in de Elektriciteitswet 1998 (de E-wet). Sinds die tijd is er in de regelgeving, beschikkingspraktijk en jurisprudentie genoeg gewijzigd om een vervolg te rechtvaardigen. Dit artikel beoogt een thematisch overzicht te geven van de ontwikkelingen in de regelgeving, de beschikkingspraktijk van de NMa en jurisprudentie met betrekking tot de elektriciteits- en gasaansluiting in de laatste drie jaar. Daarbij is waar mogelijk aangeknoopt bij de thema's in het hierboven genoemde artikel. De focus is verbreed naar aansluitingen onder zowel de E-wet als de Gaswet.

  10. Powder Forging of a Motorcycle Connecting Rod

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A motorcycle connecting rod is one of the major moving parts affecting the engine performance. The traditional manufacturing process results in material waste and excessive machining. A new method of hot forging P/M has been proposed and studied experimentally. In order to achieve uniform density, the punch was divided into three parts to consolidate the loose powder. The multistage movement of the three parts of the punch, called synchronous compaction, results in the desired uniform density. Powder flow during consolidation was illustrated and the density distribution of the compacts was measured. A set of forging dies with flash was used to produce densification and deformation of the sintered compact. Then a set of flashless forging dies was designed to obtain the desired shape and dimensions of the connecting rod. The effects of forging temperature and initial compact density on densification were evaluated through hot forging experiments. Based on properties achieved, Fe-C-Cu-Mo was selected as the alloy powder. Through testing and metallographic observation the physical and mechanical properties of the connecting rod produced by the P/M hot forging were found to be superior to those manufactured by the traditional method.

  11. Microgravity Stress: Bone and Connective Tissue.

    Science.gov (United States)

    Bloomfield, Susan A; Martinez, Daniel A; Boudreaux, Ramon D; Mantri, Anita V

    2016-04-01

    The major alterations in bone and the dense connective tissues in humans and animals exposed to microgravity illustrate the dependency of these tissues' function on normal gravitational loading. Whether these alterations depend solely on the reduced mechanical loading of zero g or are compounded by fluid shifts, altered tissue blood flow, radiation exposure, and altered nutritional status is not yet well defined. Changes in the dense connective tissues and intervertebral disks are generally smaller in magnitude but occur more rapidly than those in mineralized bone with transitions to 0 g and during recovery once back to the loading provided by 1 g conditions. However, joint injuries are projected to occur much more often than the more catastrophic bone fracture during exploration class missions, so protecting the integrity of both tissues is important. This review focuses on the research performed over the last 20 years in humans and animals exposed to actual spaceflight, as well as on knowledge gained from pertinent ground-based models such as bed rest in humans and hindlimb unloading in rodents. Significant progress has been made in our understanding of the mechanisms for alterations in bone and connective tissues with exposure to microgravity, but intriguing questions remain to be solved, particularly with reference to biomedical risks associated with prolonged exploration missions. PMID:27065165

  12. Stretching Impacts Inflammation Resolution in Connective Tissue.

    Science.gov (United States)

    Berrueta, Lisbeth; Muskaj, Igla; Olenich, Sara; Butler, Taylor; Badger, Gary J; Colas, Romain A; Spite, Matthew; Serhan, Charles N; Langevin, Helene M

    2016-07-01

    Acute inflammation is accompanied from its outset by the release of specialized pro-resolving mediators (SPMs), including resolvins, that orchestrate the resolution of local inflammation. We showed earlier that, in rats with subcutaneous inflammation of the back induced by carrageenan, stretching for 10 min twice daily reduced inflammation and improved pain, 2 weeks after carrageenan injection. In this study, we hypothesized that stretching of connective tissue activates local pro-resolving mechanisms within the tissue in the acute phase of inflammation. In rats injected with carrageenan and randomized to stretch versus no stretch for 48 h, stretching reduced inflammatory lesion thickness and neutrophil count, and increased resolvin (RvD1) concentrations within lesions. Furthermore, subcutaneous resolvin injection mimicked the effect of stretching. In ex vivo experiments, stretching of connective tissue reduced the migration of neutrophils and increased tissue RvD1 concentration. These results demonstrate a direct mechanical impact of stretching on inflammation-regulation mechanisms within connective tissue.

  13. Maximizing Algebraic Connectivity in Interconnected Networks

    CERN Document Server

    Shakeri, Heman; Sahneh, Faryad Darabi; Poggi-Corradini, Pietro; Scoglio, Caterina

    2015-01-01

    Algebraic connectivity, the second eigenvalue of the Laplacian matrix, is a measure of node and link connectivity on networks. When studying interconnected networks it is useful to consider a multiplex model, where the component networks operate together with inter-layer links among them. In order to have a well-connected multilayer structure, it is necessary to optimally design these inter-layer links considering realistic constraints. In this work, we solve the problem of finding an optimal weight distribution for one-to-one inter-layer links under budget constraint. We show that for the special multiplex configurations with identical layers, the uniform weight distribution is always optimal. On the other hand, when the two layers are arbitrary, increasing the budget reveals the existence of two different regimes. Up to a certain threshold budget, the second eigenvalue of the supra-Laplacian is simple, the optimal weight distribution is uniform, and the Fiedler vector is constant on each layer. Increasing t...

  14. Schizophrenia, abnormal connection, and brain evolution.

    Science.gov (United States)

    Randall, P L

    1983-03-01

    Abnormalities of functional connection between specialized areas in the human brain may underlie the symptoms which constitute the schizophrenia syndrome. Callosal and intrahemispheric fibres may be equally involved. The clinical emergence of symptoms in the later stages of brain maturation may be dependent on myelination of these fibre groups, both of which have extended myelination cycles. Ontogenetically earlier variants of the same mechanism could theoretically result in dyslexia and the syndromes of Kanner and Gilles de la Tourette. As new and unique extensions of specialized function emerge within the evolving brain, biological trial and error of connection both within and between them may produce individuals possessing phylogenetically advanced abilities, or equally, others possessing a wide range of abnormalities including those which comprise the schizophrenia syndrome. A dormant phenotypic potential for schizophrenia may exist in individuals who never develop symptoms during the course of a lifetime though some of these may become clinically apparent under the influence of various precipitating factors. It is concluded that abnormal functional connection and its normal and "supernormal" counterparts may be natural, essential, and inevitable consequences of brain evolution, and that this may have been so throughout the history of vertebrate brain evolution.

  15. Long-Range Connections in Transportation Networks

    CERN Document Server

    Viana, Matheus P

    2010-01-01

    Since its recent introduction, the small-world effect has been identified in several important real-world systems. Frequently, it is a consequence of the existence of a few long-range connections, which dominate the original regular structure of the systems and implies each node to become accessible from other nodes after a small number of steps, typically of order $\\ell \\propto \\log N$. However, this effect has been observed in pure-topological networks, where the nodes have no spatial coordinates. In this paper, we present an alalogue of small-world effect observed in real-world transportation networks, where the nodes are embeded in a hree-dimensional space. Using the multidimensional scaling method, we demonstrate how the addition of a few long-range connections can suubstantially reduce the travel time in transportation systems. Also, we investigated the importance of long-range connections when the systems are under an attack process. Our findings are illustrated for two real-world systems, namely the L...

  16. 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.

  17. Routing of multimedia connections in hybrid networks

    Science.gov (United States)

    Koegel, John F.; Syta, Andrzej

    1993-02-01

    The prevailing vision for next generation multimedia communication systems is a digital one. However, we anticipate a transitional period in which hybrid networks involving both analog and digital technology will coexist. These analog facilities will include crossbar audio-video switches, CATV distribution systems, and dedicated lines. For some scale of use, these facilities may offer economies for connectivity to conventional analog video equipment. We are interested in connection routing that will be needed in such hybrid networks for services including video conferencing and broadcast results. The routing problem in such topologies resembles but is not identical to that found in telephone systems because of the presence of broadcast connections. We discuss representative topologies, review related work, and describe algorithms and simulation results. In addition we describe a hybrid system that we have implemented in our research lab which involves several A/V switches, CATV channels, digital video on a LAN, and a point-to-point link to an offsite conference area.

  18. Zinc oxide: Connecting theory and experiment

    Directory of Open Access Journals (Sweden)

    Dejan Zagorac

    2013-09-01

    Full Text Available Zinc oxide (ZnO is a material with a great variety of industrial applications including high heat capacity, thermal conductivity and temperature stability. Clearly, it would be of great importance to find new stable and/or metastable modifications of zinc oxide, and investigate the influence of pressure and/or temperature on these structures, and try to connect theoretical results to experimental observations. In order to reach this goal, we performed several research studies, using modern theoretical methods. We have predicted possible crystal structures for ZnO using simulated annealing (SA, followed by investigations of the barrier structure using the threshold algorithm (TA. Finally, we have performed calculations using the prescribed path algorithm (PP, where connections between experimental structures on the energy landscape, and in particular transition states, were investigated in detail. The results were in good agreement with previous theoretical and experimental observations, where available, and we have found several additional (metastable modifications at standard, elevated and negative pressures. Furthermore, we were able to gain new insight into synthesis conditions for the various ZnO modifications and to connect our results to the actual synthesis and transformation routes.

  19. Spherical Joint Piston and Connecting Rod Developed

    Science.gov (United States)

    1996-01-01

    Under an interagency agreement with the Department of Energy, the NASA Lewis Research Center manages a Heavy-Duty Diesel Engine Technology (HDET) research program. The overall program objectives are to reduce fuel consumption through increased engine efficiency, reduce engine exhaust emissions, and provide options for the use of alternative fuels. The program is administered with a balance of research contracts, university research grants, and focused in-house research. The Cummins Engine Company participates in the HDET program under a cost-sharing research contract. Cummins is researching and developing in-cylinder component technologies for heavy-duty diesel engines. An objective of the Cummins research is to develop technologies for a low-emissions, 55-percent thermal efficiency (LE-55) engine. The best current-production engines in this class achieve about 46-percent thermal efficiency. Federal emissions regulations are driving this technology. Regulations for heavy duty diesel engines were tightened in 1994, more demanding emissions regulations are scheduled for 1998, and another step is planned for 2002. The LE-55 engine emissions goal is set at half of the 1998 regulation level and is consistent with plans for 2002 emissions regulations. LE-55 engine design requirements to meet the efficiency target dictate a need to operate at higher peak cylinder pressures. A key technology being developed and evaluated under the Cummins Engine Company LE-55 engine concept is the spherical joint piston and connecting rod. Unlike conventional piston and connecting rod arrangements which are joined by a pin forming a hinged joint, the spherical joint piston and connecting rod use a ball-and-socket joint. The ball-and-socket arrangement enables the piston to have an axisymmetric design allowing rotation within the cylinder. The potential benefits of piston symmetry and rotation are reduced scuffing, improved piston ring sealing, improved lubrication, mechanical and thermal

  20. Auditory hedonic phenotypes in dementia: A behavioural and neuroanatomical analysis.

    Science.gov (United States)

    Fletcher, Phillip D; Downey, Laura E; Golden, Hannah L; Clark, Camilla N; Slattery, Catherine F; Paterson, Ross W; Schott, Jonathan M; Rohrer, Jonathan D; Rossor, Martin N; Warren, Jason D

    2015-06-01

    Patients with dementia may exhibit abnormally altered liking for environmental sounds and music but such altered auditory hedonic responses have not been studied systematically. Here we addressed this issue in a cohort of 73 patients representing major canonical dementia syndromes (behavioural variant frontotemporal dementia (bvFTD), semantic dementia (SD), progressive nonfluent aphasia (PNFA) amnestic Alzheimer's disease (AD)) using a semi-structured caregiver behavioural questionnaire and voxel-based morphometry (VBM) of patients' brain MR images. Behavioural responses signalling abnormal aversion to environmental sounds, aversion to music or heightened pleasure in music ('musicophilia') occurred in around half of the cohort but showed clear syndromic and genetic segregation, occurring in most patients with bvFTD but infrequently in PNFA and more commonly in association with MAPT than C9orf72 mutations. Aversion to sounds was the exclusive auditory phenotype in AD whereas more complex phenotypes including musicophilia were common in bvFTD and SD. Auditory hedonic alterations correlated with grey matter loss in a common, distributed, right-lateralised network including antero-mesial temporal lobe, insula, anterior cingulate and nucleus accumbens. Our findings suggest that abnormalities of auditory hedonic processing are a significant issue in common dementias. Sounds may constitute a novel probe of brain mechanisms for emotional salience coding that are targeted by neurodegenerative disease. PMID:25929717

  1. A neuroanatomical dissociation for emotion induced by music

    OpenAIRE

    Johnsen, Erica L.; Tranel, Daniel; Lutgendorf, Susan; Adolphs, Ralph

    2009-01-01

    Does feeling an emotion require changes in autonomic responses, as William James proposed? Can feelings and autonomic responses be dissociated? Findings from cognitive neuroscience have identified brain structures that subserve feelings and autonomic response, including those induced by emotional music. In the study reported here, we explored whether feelings and autonomic responses can be dissociated by using music, a stimulus that has a strong capacity to induce emotional experiences. We te...

  2. Neuroanatomical substrates for the volitional regulation of heart rate

    Directory of Open Access Journals (Sweden)

    Catherine Louise Jones

    2015-03-01

    Full Text Available The control of physiological arousal can assist in the regulation of emotional state. A subset cortical and subcortical brain regions are implicated in autonomic control of bodily arousal during emotional behaviours. Here, we combined human functional neuroimaging with autonomic monitoring to identify neural mechanisms that support the volitional regulation of heart rate, a process that may be assisted by visual feedback. During functional magnetic resonance imaging, fifteen healthy adults performed an experimental task in which they were prompted voluntarily to increase or decrease cardiovascular arousal (heart rate during true, false or absent visual feedback. Participants achieved appropriate changes in heart rate, without significant modulation of respiratory rate, and were overall not influenced by the presence of visual feedback. Increased activity in right amygdala, striatum and brainstem occurred when participants attempted to increase heart rate. In contrast, activation of ventrolateral prefrontal and parietal cortices occurred when attempting to decrease heart rate. Biofeedback enhanced activity within occipito-temporal cortices, but there was no significant interaction with task conditions. Activity in regions including pregenual anterior cingulate and ventral striatum reflected the magnitude of successful task performance, which was negatively related to subclinical anxiety symptoms. Measured changes in respiration correlated with posterior insula activation and heart rate, at a more lenient threshold, change correlated with insula, caudate and midbrain activity. Our findings highlight a set of brain regions, notably ventrolateral prefrontal cortex, supporting volitional control of cardiovascular arousal. These data are relevant to understanding neural substrates supporting interaction between intentional and interoceptive states related to anxiety, with implications for biofeedback interventions, e.g. real-time fMRI, that target emotional regulation

  3. Neuroanatomical substrates for the volitional regulation of heart rate.

    Science.gov (United States)

    Jones, Catherine L; Minati, Ludovico; Nagai, Yoko; Medford, Nick; Harrison, Neil A; Gray, Marcus; Ward, Jamie; Critchley, Hugo D

    2015-01-01

    The control of physiological arousal can assist in the regulation of emotional state. A subset cortical and subcortical brain regions are implicated in autonomic control of bodily arousal during emotional behaviors. Here, we combined human functional neuroimaging with autonomic monitoring to identify neural mechanisms that support the volitional regulation of heart rate, a process that may be assisted by visual feedback. During functional magnetic resonance imaging (fMRI), 15 healthy adults performed an experimental task in which they were prompted voluntarily to increase or decrease cardiovascular arousal (heart rate) during true, false, or absent visual feedback. Participants achieved appropriate changes in heart rate, without significant modulation of respiratory rate, and were overall not influenced by the presence of visual feedback. Increased activity in right amygdala, striatum and brainstem occurred when participants attempted to increase heart rate. In contrast, activation of ventrolateral prefrontal and parietal cortices occurred when attempting to decrease heart rate. Biofeedback enhanced activity within occipito-temporal cortices, but there was no significant interaction with task conditions. Activity in regions including pregenual anterior cingulate and ventral striatum reflected the magnitude of successful task performance, which was negatively related to subclinical anxiety symptoms. Measured changes in respiration correlated with posterior insula activation and heart rate, at a more lenient threshold, change correlated with insula, caudate, and midbrain activity. Our findings highlight a set of brain regions, notably ventrolateral prefrontal cortex, supporting volitional control of cardiovascular arousal. These data are relevant to understanding neural substrates supporting interaction between intentional and interoceptive states related to anxiety, with implications for biofeedback interventions, e.g., real-time fMRI, that target emotional regulation. PMID:25992711

  4. Neuroanatomical substrates involved in true and false memories for face.

    Science.gov (United States)

    Iidaka, Tetsuya; Harada, Tokiko; Kawaguchi, Jun; Sadato, Norihiro

    2012-08-01

    We often mistake an unknown person for a familiar person because of the similarities in facial features. This phenomenon, known as false memory, has been investigated mainly using words, pictures, and shapes. Previous neuroimaging studies on false memory have shown that both true and false memories trigger a similar activation in the medial temporal lobe, suggesting that it plays a common role in both. However, no study to date has investigated neural substrates of false memories for faces. In the present fMRI study, we applied a modified version of the standard false memory paradigm, using morphed pictures of faces, to induce false memory in an MRI environment. We found that activity in the amygdala and orbital cortices was associated with the degree of familiarity of items. In particular, false responses to "lure" items evoked a level of activity in the amygdala between that evoked for correct or incorrect responses to "true" items. This indicates a possible role of the amygdala in false memory. A specific region in the anterior cingulate cortex was involved in false recognition; the activity being correlated to reaction times for the response types. These results suggest that the amygdala is involved in determining the relevance of items; therefore, ambiguousness of lure items in terms of familiarity and novelty may be related to decreased activity in the amygdala. The anterior cingulate activity in false memory may be caused not only by increased effort and motor demand but also by higher mnemonic processing of lure items. PMID:22575420

  5. Neuroanatomical Substrates of Age-Related Cognitive Decline

    Science.gov (United States)

    Salthouse, Timothy A.

    2011-01-01

    There are many reports of relations between age and cognitive variables and of relations between age and variables representing different aspects of brain structure and a few reports of relations between brain structure variables and cognitive variables. These findings have sometimes led to inferences that the age-related brain changes cause the…

  6. Neuroanatomical Correlates of Oral Reading in Acute Left Hemispheric Stroke

    Science.gov (United States)

    Cloutman, Lauren L.; Newhart, Melisssa; Davis, Cameron L.; Heidler-Gary, Jennifer; Hillis, Argye E.

    2011-01-01

    Oral reading is a complex skill involving the interaction of orthographic, phonological, and semantic processes. Functional imaging studies with nonimpaired adult readers have identified a widely distributed network of frontal, inferior parietal, posterior temporal, and occipital brain regions involved in the task. However, while functional…

  7. The Evolving Neuroanatomical Component of the Foundational Model of Anatomy

    OpenAIRE

    Martin, Richard F.; Rickard, Kurt; Mejino, José L.V.; Agoncillo, Augusto V.; Brinkley, James F.; Rosse, Cornelius

    2003-01-01

    In order to meet the need for an expressive ontology in neuroinformatics, we have integrated the extensive terminologies of NeuroNames and Terminologia Anatomica into the Foundational Model of Anatomy (FMA). We have enhanced the FMA to accommodate information unique to neuronal structures, such as axonal input/output relationships.

  8. Holothurian Nervous System Diversity Revealed by Neuroanatomical Analysis.

    Science.gov (United States)

    Díaz-Balzac, Carlos A; Lázaro-Peña, María I; Vázquez-Figueroa, Lionel D; Díaz-Balzac, Roberto J; García-Arrarás, José E

    2016-01-01

    The Echinodermata comprise an interesting branch in the phylogenetic tree of deuterostomes. Their radial symmetry which is reflected in their nervous system anatomy makes them a target of interest in the study of nervous system evolution. Until recently, the study of the echinoderm nervous system has been hindered by a shortage of neuronal markers. However, in recent years several markers of neuronal and fiber subpopulations have been described. These have been used to identify subpopulations of neurons and fibers, but an integrative study of the anatomical relationship of these subpopulations is wanting. We have now used eight commercial antibodies, together with three antibodies produced by our group to provide a comprehensive and integrated description and new details of the echinoderm neuroanatomy using the holothurian Holothuria glaberrima (Selenka, 1867) as our model system. Immunoreactivity of the markers used showed: (1) specific labeling patterns by markers in the radial nerve cords, which suggest the presence of specific nerve tracts in holothurians. (2) Nerves directly innervate most muscle fibers in the longitudinal muscles. (3) Similar to other deuterostomes (mainly vertebrates), their enteric nervous system is composed of a large and diverse repertoire of neurons and fiber phenotypes. Our results provide a first blueprint of the anatomical organization of cells and fibers that form the holothurian neural circuitry, and highlight the fact that the echinoderm nervous system shows unexpected diversity in cell and fiber types and their distribution in both central and peripheral nervous components.

  9. A neuroanatomical dissociation for emotion induced by music.

    Science.gov (United States)

    Johnsen, Erica L; Tranel, Daniel; Lutgendorf, Susan; Adolphs, Ralph

    2009-04-01

    Does feeling an emotion require changes in autonomic responses, as William James proposed? Can feelings and autonomic responses be dissociated? Findings from cognitive neuroscience have identified brain structures that subserve feelings and autonomic response, including those induced by emotional music. In the study reported here, we explored whether feelings and autonomic responses can be dissociated by using music, a stimulus that has a strong capacity to induce emotional experiences. We tested two brain regions predicted to be differentially involved in autonomic responsivity (the ventromedial prefrontal cortex) and feeling (the right somatosensory cortex). Patients with damage to the ventromedial prefrontal cortex were impaired in their ability to generate skin-conductance responses to music, but generated normal judgments of their subjective feelings in response to music. Conversely, patients with damage to the right somatosensory cortex were impaired in their self-rated feelings in response to music, but generated normal skin-conductance responses to music. Control tasks suggested that neither impairment was due to basic defects in hearing the music or in cognitively recognizing the intended emotion of the music. The findings provide evidence for a double dissociation between feeling emotions and autonomic responses to emotions, in response to music stimuli.

  10. Neuroanatomical substrates of executive functions: Beyond prefrontal structures.

    Science.gov (United States)

    Bettcher, Brianne M; Mungas, Dan; Patel, Nihar; Elofson, Jonathan; Dutt, Shubir; Wynn, Matthew; Watson, Christa L; Stephens, Melanie; Walsh, Christine M; Kramer, Joel H

    2016-05-01

    Executive functions are often considered lynchpin "frontal lobe tasks", despite accumulating evidence that a broad network of anterior and posterior brain structures supports them. Using a latent variable modelling approach, we assessed whether prefrontal grey matter volumes independently predict executive function performance when statistically differentiated from global atrophy and individual non-frontal lobar volume contributions. We further examined whether fronto-parietal white matter microstructure underlies and independently contributes to executive functions. We developed a latent variable model to decompose lobar grey matter volumes into a global grey matter factor and specific lobar volumes (i.e. prefrontal, parietal, temporal, occipital) that were independent of global grey matter. We then added mean fractional anisotropy (FA) for the superior longitudinal fasciculus (dorsal portion), corpus callosum, and cingulum bundle (dorsal portion) to models that included grey matter volumes related to cognitive variables in previous analyses. Results suggested that the 2-factor model (shifting/inhibition, updating/working memory) plus an information processing speed factor best explained our executive function data in a sample of 202 community dwelling older adults, and was selected as the base measurement model for further analyses. Global grey matter was related to the executive function and speed variables in all four lobar models, but independent contributions of the frontal lobes were not significant. In contrast, when assessing the effect of white matter microstructure, cingulum FA made significant independent contributions to all three executive function and speed variables and corpus callosum FA was independently related to shifting/inhibition and speed. Findings from the current study indicate that while prefrontal grey matter volumes are significantly associated with cognitive neuroscience measures of shifting/inhibition and working memory in healthy older adults, they do not independently predict executive function when statistically isolated from global atrophy and individual non-frontal lobar volume contributions. In contrast, better microstructure of fronto-parietal white matter, namely the corpus callosum and cingulum, continued to predict executive functions after accounting for global grey matter atrophy. These findings contribute to a growing literature suggesting that prefrontal contributions to executive functions cannot be viewed in isolation from more distributed grey and white matter effects in a healthy older adult cohort. PMID:26948072

  11. The Mind-Body Connection - Emotions and Health

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues The Mind-Body Connection Emotions and Health Past Issues / Winter ... Today, we accept that there is a powerful mind-body connection through which emotional, mental, social, spiritual, ...

  12. A method for connecting electrodes in a storage battery

    Energy Technology Data Exchange (ETDEWEB)

    Toda, K.; Karasava, S.

    1983-07-14

    The electrode units, placed into the body of a storage battery (AB), are electrically connected by welding connecting elements which pass through the partitions in the body. The processing is conducted with heating and pressure simultaneously.

  13. Real-Time Connect 4 Game Using Artificial Intelligence

    Directory of Open Access Journals (Sweden)

    Ahmad M. Sarhan

    2009-01-01

    Full Text Available Problem statement: The study presented a design that converted connect 4 game into a real-time game by incorporating time restraints. Approach: The design used Artificial Intelligence (AI in implementing the connect 4 game. The AI for this game was based on influence mapping. Results: A waterfall-based AI software was developed for a Connect 4 game. Conclusion: A real time connect 4 game was successfully designed and implanted with GUI using C++ programming language.

  14. FEA ANALYSIS OF GEOMETRIC PARAMETERS OF CONNECTING ROD BIG END

    OpenAIRE

    SURENDRA PRASAD BARATAM; SANJAY B CHIKALTHANKAR; V. M. Nandedkar

    2012-01-01

    The automobile engine connecting rod is a high volume production, critical component. It connects reciprocating piston to rotating crankshaft, transmitting the thrust of the piston to the crankshaft. In order to carry out successfully the function, it is needed to grasp the rotating crankshaft and also to keep the good stiffness of the big-end of the connecting rod in acceptable ranges during engine operation. When the stiffness of the Connecting rod is needed to be reinforced, in general, so...

  15. Finite Element Models for Thin-Walled Steel Member Connections

    OpenAIRE

    Sandesh R. Acharya; Sivakumaran, K. S.

    2012-01-01

    The behavior of connections associated with the thin-walled steel members is distinctly different from that of hot-rolled steel connections, primarily because of the flexibility of the plates. A typical cold-formed steel structural construction may entail such numerous connections. The incorporation of large number of such connections in an analysis and design, using sophisticated finite element models, is very tedious and time consuming and may present computational difficulties. The objecti...

  16. Transient stability impacts from distribution connected wind farms

    OpenAIRE

    Vittal, Eknath; Cuffe, Paul; Keane, Andrew

    2012-01-01

    Wind generation penetration levels are increasing in power systems across the world. Along with transmission connected wind farms, distribution connected wind farms are becoming more prevalent in power systems. How these distribution connected farms control reactive power is of concern to the transmission system operator. This paper examines a hybrid system, where the transmission system is modeled with a significant penetration level of radial distribution feeders connected to a collection o...

  17. Connectivity in Logistics and Supply Chain Management: A Framework

    OpenAIRE

    Hoffman, Karolin; Hellström, Daniel

    2008-01-01

    This paper seeks to investigate the connectivity construct in logistics and supply chain management literature. A review of existing literature is conducted regarding connectivity on a broad basis. The review is based on a general search in the ABI-Inform database for articles containing the twin search phrases of connectivity and logistics, and connectivity and supply chain management. An initial analysis of articles found resulted in a total of 195 articles, of which 76 are found to be rele...

  18. Upper bound of the third edge-connectivity of graphs

    Institute of Scientific and Technical Information of China (English)

    WANG; Yingqian; LI; Qiao

    2005-01-01

    Let G be a simple connected graph of order n ≥ 6. The third edge-connectivity of G is defined as the minimum cardinality over all the sets of edges, if any, whose deletion disconnects G and every component of the resulting graph has at least 3 vertices. In this paper, we first characterize those graphs whose third-edge connectivity is well defined,then establish the tight upper bound for the third edge-connectivity.

  19. The Role of Connectivity in Supporting Context-Sensitive Applications

    OpenAIRE

    Cheverst, Keith; Davies, Nigel; Mitchell, Keith; Friday, Adrian

    1999-01-01

    This paper considers the role of network connectivity in supporting context-sensitive applications. A range of context-sensitive applications are analysed with respect to connectivity. Following this analysis a design space is constructed which enables the positioning of context-sensitive applications depending on their reliance on network connectivity and their reliance on local storage. Further consideration of the role of connectivity is achieved through a study of the GUIDE system which h...

  20. Home awareness - connecting people sensuously to places

    DEFF Research Database (Denmark)

    Lynggaard, Aviaja Borup; Petersen, Marianne Graves; Gude, Rasmus;

    2010-01-01

    People living a global lifestyle connect remotely to their families while away from home. In this paper we identify a need for connecting with a home as the physical place itself. For this purpose we introduce the concept of Home Awareness that connects people sensuously to remote places through...