WorldWideScience

Sample records for evaluating effective connectivity

  1. Effect of Explicit Evaluation on Neural Connectivity Related to Listening to Unfamiliar Music

    Science.gov (United States)

    Liu, Chao; Brattico, Elvira; Abu-jamous, Basel; Pereira, Carlos S.; Jacobsen, Thomas; Nandi, Asoke K.

    2017-01-01

    People can experience different emotions when listening to music. A growing number of studies have investigated the brain structures and neural connectivities associated with perceived emotions. However, very little is known about the effect of an explicit act of judgment on the neural processing of emotionally-valenced music. In this study, we adopted the novel consensus clustering paradigm, called binarisation of consensus partition matrices (Bi-CoPaM), to study whether and how the conscious aesthetic evaluation of the music would modulate brain connectivity networks related to emotion and reward processing. Participants listened to music under three conditions – one involving a non-evaluative judgment, one involving an explicit evaluative aesthetic judgment, and one involving no judgment at all (passive listening only). During non-evaluative attentive listening we obtained auditory-limbic connectivity whereas when participants were asked to decide explicitly whether they liked or disliked the music excerpt, only two clusters of intercommunicating brain regions were found: one including areas related to auditory processing and action observation, and the other comprising higher-order structures involved with visual processing. Results indicate that explicit evaluative judgment has an impact on the neural auditory-limbic connectivity during affective processing of music. PMID:29311874

  2. Evaluating the effectiveness of restoring longitudinal connectivity for stream fish communities: towards a more holistic approach.

    Science.gov (United States)

    Tummers, Jeroen S; Hudson, Steve; Lucas, Martyn C

    2016-11-01

    A more holistic approach towards testing longitudinal connectivity restoration is needed in order to establish that intended ecological functions of such restoration are achieved. We illustrate the use of a multi-method scheme to evaluate the effectiveness of 'nature-like' connectivity restoration for stream fish communities in the River Deerness, NE England. Electric-fishing, capture-mark-recapture, PIT telemetry and radio-telemetry were used to measure fish community composition, dispersal, fishway efficiency and upstream migration respectively. For measuring passage and dispersal, our rationale was to evaluate a wide size range of strong swimmers (exemplified by brown trout Salmo trutta) and weak swimmers (exemplified by bullhead Cottus perifretum) in situ in the stream ecosystem. Radio-tracking of adult trout during the spawning migration showed that passage efficiency at each of five connectivity-restored sites was 81.3-100%. Unaltered (experimental control) structures on the migration route had a bottle-neck effect on upstream migration, especially during low flows. However, even during low flows, displaced PIT tagged juvenile trout (total n=153) exhibited a passage efficiency of 70.1-93.1% at two nature-like passes. In mark-recapture experiments juvenile brown trout and bullhead tagged (total n=5303) succeeded in dispersing upstream more often at most structures following obstacle modification, but not at the two control sites, based on a Laplace kernel modelling approach of observed dispersal distance and barrier traverses. Medium-term post-restoration data (2-3years) showed that the fish assemblage remained similar at five of six connectivity-restored sites and two control sites, but at one connectivity-restored headwater site previously inhabited by trout only, three native non-salmonid species colonized. We conclude that stream habitat reconnection should support free movement of a wide range of species and life stages, wherever retention of such

  3. Evaluation of 604 Connect

    OpenAIRE

    Ladner, S.; Ihnat, M.

    2000-01-01

    The Vancouver Community Network (VCN) is a not-for-profit Internet Service Provider (ISP), based on the “freenet” model of public Internet access. As a VolNet delivery agency, VCN committed to providing participating organizations with the following: (1) A communications protocol, (2) Internet Access, (3) Computer Equipment, (4) Training, and (5) Technical Support. In April 1999, VCN began receiving applications from non-profit organizations for its 604 Connect program, so named for the 604 t...

  4. How art changes your brain: differential effects of visual art production and cognitive art evaluation on functional brain connectivity.

    Science.gov (United States)

    Bolwerk, Anne; Mack-Andrick, Jessica; Lang, Frieder R; Dörfler, Arnd; Maihöfner, Christian

    2014-01-01

    Visual art represents a powerful resource for mental and physical well-being. However, little is known about the underlying effects at a neural level. A critical question is whether visual art production and cognitive art evaluation may have different effects on the functional interplay of the brain's default mode network (DMN). We used fMRI to investigate the DMN of a non-clinical sample of 28 post-retirement adults (63.71 years ±3.52 SD) before (T0) and after (T1) weekly participation in two different 10-week-long art interventions. Participants were randomly assigned to groups stratified by gender and age. In the visual art production group 14 participants actively produced art in an art class. In the cognitive art evaluation group 14 participants cognitively evaluated artwork at a museum. The DMN of both groups was identified by using a seed voxel correlation analysis (SCA) in the posterior cingulated cortex (PCC/preCUN). An analysis of covariance (ANCOVA) was employed to relate fMRI data to psychological resilience which was measured with the brief German counterpart of the Resilience Scale (RS-11). We observed that the visual art production group showed greater spatial improvement in functional connectivity of PCC/preCUN to the frontal and parietal cortices from T0 to T1 than the cognitive art evaluation group. Moreover, the functional connectivity in the visual art production group was related to psychological resilience (i.e., stress resistance) at T1. Our findings are the first to demonstrate the neural effects of visual art production on psychological resilience in adulthood.

  5. How Art Changes Your Brain: Differential Effects of Visual Art Production and Cognitive Art Evaluation on Functional Brain Connectivity

    Science.gov (United States)

    Bolwerk, Anne; Mack-Andrick, Jessica; Lang, Frieder R.; Dörfler, Arnd; Maihöfner, Christian

    2014-01-01

    Visual art represents a powerful resource for mental and physical well-being. However, little is known about the underlying effects at a neural level. A critical question is whether visual art production and cognitive art evaluation may have different effects on the functional interplay of the brain's default mode network (DMN). We used fMRI to investigate the DMN of a non-clinical sample of 28 post-retirement adults (63.71 years ±3.52 SD) before (T0) and after (T1) weekly participation in two different 10-week-long art interventions. Participants were randomly assigned to groups stratified by gender and age. In the visual art production group 14 participants actively produced art in an art class. In the cognitive art evaluation group 14 participants cognitively evaluated artwork at a museum. The DMN of both groups was identified by using a seed voxel correlation analysis (SCA) in the posterior cingulated cortex (PCC/preCUN). An analysis of covariance (ANCOVA) was employed to relate fMRI data to psychological resilience which was measured with the brief German counterpart of the Resilience Scale (RS-11). We observed that the visual art production group showed greater spatial improvement in functional connectivity of PCC/preCUN to the frontal and parietal cortices from T0 to T1 than the cognitive art evaluation group. Moreover, the functional connectivity in the visual art production group was related to psychological resilience (i.e., stress resistance) at T1. Our findings are the first to demonstrate the neural effects of visual art production on psychological resilience in adulthood. PMID:24983951

  6. Evaluation of the effect of human immunodeficiency virus-related structural interventions: the connect to protect project.

    Science.gov (United States)

    Ellen, Jonathan M; Greenberg, Lauren; Willard, Nancy; Korelitz, James; Kapogiannis, Bill G; Monte, Dina; Boyer, Cherrie B; Harper, Gary W; Henry-Reid, Lisa M; Friedman, Lawrence B; Gonin, René

    2015-03-01

    With the emphasis on structural-level interventions that target social determinants of human immunodeficiency virus (HIV) transmission to curb the HIV epidemic, there is a need to develop evaluation models that can detect changes in individual factors associated with HIV-related structural changes. To describe whether structural changes developed and achieved by community coalitions are associated with an effect on individual factors associated with the risk of contracting HIV. In this serial cross-sectional survey design, data were collected from 8 cities during 4 rounds of annual surveys from March 13, 2007, through July 29, 2010. Study recruitment took place at venues where the population of focus was known to congregate, such as clubs, bars, community centers, and low-income housing. The convenience sample of at-risk youth (persons aged 12-24 years) included 5337 individuals approached about the survey and 3142 (58.9%) who were screened for eligibility. Of the 2607 eligible participants, 2559 (98.2%) ultimately agreed to participate. Achievement of locally identified structural changes that targeted public and private entities (eg, federal agencies, homeless shelters, and school systems) with the goal of fostering changes in policy and practice to ultimately facilitate positive behavioral changes aimed at preventing HIV. Number of sexual partners, partner characteristics, condom use, and history of sexually transmitted infections and HIV testing. Exposure to structural changes was not statistically significantly associated with any of the outcome measures, although some results were in the direction of a positive structural change effect (eg, a 10-unit increase in a structural change score had an odds ratio of 0.88 [95% CI, 0.76-1.03; P = .11] for having an older sexual partner and an odds ratio of 0.91 [95% CI, 0.60-1.39; P = .39] for using a condom half the time or less with a casual partner). This study evaluated a broad representation of at

  7. Use of functional near-infrared spectroscopy to evaluate the effects of anodal transcranial direct current stimulation on brain connectivity in motor-related cortex

    Science.gov (United States)

    Yan, Jiaqing; Wei, Yun; Wang, Yinghua; Xu, Gang; Li, Zheng; Li, Xiaoli

    2015-04-01

    Transcranial direct current stimulation (tDCS) is a noninvasive, safe and convenient neuro-modulatory technique in neurological rehabilitation, treatment, and other aspects of brain disorders. However, evaluating the effects of tDCS is still difficult. We aimed to evaluate the effects of tDCS using hemodynamic changes using functional near-infrared spectroscopy (fNIRS). Five healthy participants were employed and anodal tDCS was applied to the left motor-related cortex, with cathodes positioned on the right dorsolateral supraorbital area. fNIRS data were collected from the right motor-related area at the same time. Functional connectivity (FC) between intracortical regions was calculated between fNIRS channels using a minimum variance distortion-less response magnitude squared coherence (MVDR-MSC) method. The levels of Oxy-HbO change and the FC between channels during the prestimulation, stimulation, and poststimulation stages were compared. Results showed no significant level difference, but the FC measured by MVDR-MSC significantly decreased during tDCS compared with pre-tDCS and post-tDCS, although the FC difference between pre-tDCS and post-tDCS was not significant. We conclude that coherence calculated from resting state fNIRS may be a useful tool for evaluating the effects of anodal tDCS and optimizing parameters for tDCS application.

  8. Effect of ionizing radiations on connective tissue

    International Nuclear Information System (INIS)

    Altman, K.I.; Gerber, G.B.

    1980-01-01

    The effects of ionizing radiations on connective tissue in lung, heart, vasculature, kidney, skin, and skeletal tissues are reviewed. Special emphasis is given to the effect of ionizing radiations on vasculo-connective tissue and fibrotic changes following radiation-induced injury to organs and tissues. In order to put the subject matter in proper prospective, the general biochemistry, physiology, and pathology of connective tissue is reviewed briefly together with the participation of connective tissue in disease. The review closes with an assessment of future problems and an enumeration and discussion of important, as yet unanswered questions

  9. Courant algebroid connections and string effective actions

    OpenAIRE

    Jurčo, B.

    2017-01-01

    Courant algebroids are a natural generalization of quadratic Lie algebras, appearing in various contexts in mathematical physics. A connection on a Courant algebroid gives an analogue of a covariant derivative compatible with a given fiber-wise metric. Imposing further conditions resembling standard Levi-Civita connections, one obtains a class of connections whose curvature tensor in certain cases gives a new geometrical description of equations of motion of low energy effective action of str...

  10. Structural and effective connectivity in focal epilepsy

    Directory of Open Access Journals (Sweden)

    Christopher S. Parker

    2018-01-01

    Full Text Available Patients with medically-refractory focal epilepsy may be candidates for neurosurgery and some may require placement of intracranial EEG electrodes to localise seizure onset. Assessing cerebral responses to single pulse electrical stimulation (SPES may give diagnostically useful data. SPES produces cortico-cortical evoked potentials (CCEPs, which infer effective brain connectivity. Diffusion-weighted images and tractography may be used to estimate structural brain connectivity. This combination provides the opportunity to observe seizure onset and its propagation throughout the brain, spreading contiguously along the cortex explored with electrodes, or non-contiguously. We analysed CCEPs and diffusion tractography in seven focal epilepsy patients and reconstructed the effective and structural brain networks. We aimed to assess the inter-modal similarity of the networks at a large scale across the cortex, the effective and structural connectivity of the ictal-onset zone, and investigate potential mechanisms of non-contiguous seizure spread. We found a significant overlap between structural and effective networks. Effective network CCEP amplitude, baseline variation, and outward connectivity was higher at ictal-onset zones, while structural connection strength within the ictal-onset zone tended to be higher. These findings support the concept of hyperexcitable cortex being associated with seizure generation. The high prevalence of structural and effective connections from the ictal-onset zone to sites of non-contiguous spread suggests that macroscopic structural and effective connections are plausible routes for non-contiguous seizure spread.

  11. Transistor Effect in Improperly Connected Transistors.

    Science.gov (United States)

    Luzader, Stephen; Sanchez-Velasco, Eduardo

    1996-01-01

    Discusses the differences between the standard representation and a realistic representation of a transistor. Presents an experiment that helps clarify the explanation of the transistor effect and shows why transistors should be connected properly. (JRH)

  12. Evaluation of PEGIT duct connection system

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Brenner, Douglas E.; Sherman, Max H.; Dickerhoff, Darryl J.

    2003-08-01

    Most air duct system components are assembled in the field and are mechanically fastened by sheet metal screws (for sheet metal-to-sheet metal) or by drawbands (for flex duct-to-sheet metal). Air sealing is separate from this mechanical fastening and is usually achieved using tape or mastic products after mechanical fastening. Field observations have shown that mechanical fastening rarely meets code or manufacturers requirements and that sealing procedures are similarly inconsistent. To address these problems, Proctor Engineering Group (PEG) is developing a system of joining ducts (called PEGIT) that combines the mechanical fastening and sealing into a single self-contained procedure. The PEGIT system uses a shaped flexible seal between specially designed sheet metal duct fittings to both seal and fasten duct sections together. Figure 1 shows the inner duct fitting complete with rubber seal. This seal provides the air seal for the completed fitting and is shaped to allow the inner and outer fittings to slide together, and then to lock the fittings in place. The illustration in Figure 2 shows the approximate cross section of the rubber seal that shows how the seal has a lip that is angled backwards. This angled lip allows the joint to be pushed together by folding flat but then its long axis makes it stiff in the pulling apart direction. This study was undertaken to assist PEG in some of the design aspects of this system and to test the performance of the PEGIT system. This study was carried out in three phases. The initial phase evaluated the performance of a preliminary seal design for the PEGIT system. After the first phase, the seal was redesigned and this new seal was evaluated in the second phase of testing. The third phase performed more detailed testing of the second seal design to optimize the production tolerances of the sheet metal fittings. This report summarizes our findings from the first two phases and provides details about the third phase of testing.

  13. Assessing the Effectiveness of a Mathematics-Focused, Instructional Technology Program for Grades 6-8: A 5-Year Trend Analysis of NASA CONNECT(tm) Evaluation Data

    Science.gov (United States)

    Glassman, Nanci A.; Perry, Jeannine B.; Giersch, Christopher E.; Lambert, Matthew A.; Pinelli, Thomas E.

    2004-01-01

    NASA CONNECT is a research-, inquiry, and standards-based, integrated mathematics, science, and technology series of 30-minute instructional distance learning (television and web-based) programs for students in grades 6 8. Respondents who evaluated the programs in the series over the first five seasons (1998-99 through 2002-03) reported that (1) they used the programs in the series; (2) the goals and objectives for the series were met; (3) the programs were aligned with the national mathematics, science, and technology standards; (4) the program content was developmentally appropriate for the grade level; and (5) the programs in the series enhanced and enriched the teaching of mathematics, science, and technology.

  14. Predicting the cumulative effect of multiple disturbances on seagrass connectivity.

    Science.gov (United States)

    Grech, Alana; Hanert, Emmanuel; McKenzie, Len; Rasheed, Michael; Thomas, Christopher; Tol, Samantha; Wang, Mingzhu; Waycott, Michelle; Wolter, Jolan; Coles, Rob

    2018-03-15

    The rate of exchange, or connectivity, among populations effects their ability to recover after disturbance events. However, there is limited information on the extent to which populations are connected or how multiple disturbances affect connectivity, especially in coastal and marine ecosystems. We used network analysis and the outputs of a biophysical model to measure potential functional connectivity and predict the impact of multiple disturbances on seagrasses in the central Great Barrier Reef World Heritage Area (GBRWHA), Australia. The seagrass networks were densely connected, indicating that seagrasses are resilient to the random loss of meadows. Our analysis identified discrete meadows that are important sources of seagrass propagules and that serve as stepping stones connecting various different parts of the network. Several of these meadows were close to urban areas or ports and likely to be at risk from coastal development. Deep water meadows were highly connected to coastal meadows and may function as a refuge, but only for non-foundation species. We evaluated changes to the structure and functioning of the seagrass networks when one or more discrete meadows were removed due to multiple disturbance events. The scale of disturbance required to disconnect the seagrass networks into two or more components was on average >245 km, about half the length of the metapopulation. The densely connected seagrass meadows of the central GBRWHA are not limited by the supply of propagules; therefore, management should focus on improving environmental conditions that support natural seagrass recruitment and recovery processes. Our study provides a new framework for assessing the impact of global change on the connectivity and persistence of coastal and marine ecosystems. Without this knowledge, management actions, including coastal restoration, may prove unnecessary and be unsuccessful. © 2018 John Wiley & Sons Ltd.

  15. Evaluation of connected vehicle impact on mobility and mode choice

    Directory of Open Access Journals (Sweden)

    Simon Minelli

    2015-10-01

    Full Text Available Connected vehicle is emerging as a solution to exacerbating congestion problems in urban areas. It is important to understand the impacts of connected vehicle on network and travel behavior of road users. The main objective of this paper is to evaluate the impact of connected vehicle on the mode choice and mobility of transportation networks. An iterative methodology was used in this paper where demands for various modes were modified based on the changes in travel time between each origin-destination (OD pair caused by introduction of connected vehicle. Then a traffic assignment was performed in a micro-simulation model, which was able to accurately simulate vehicle-to-vehicle communication. It is assumed that vehicles are equipped with a dynamic route guidance technology to choose their own route using real-time traffic information obtained through communication. The travel times obtained from the micro-simulation model were compared with a base scenario with no connected vehicle. The methodology was tested for a portion of Downtown Toronto, Ontario, Canada. In order to quantify changes in mode share with changes in travel time associated with each OD pair, mode choice models were developed for auto, transit, cycling and pedestrians using data mainly from the Transportation Tomorrow Survey. The impact of connected vehicle on mode choice was evaluated for different market penetrations of connected vehicle. The results of this study show that average travel times for the whole auto mode will generally increase, with the largest increase from connected vehicles. This causes an overall move away from the auto mode for high market penetrations if a dynamic route guidance algorithm is implemented.

  16. A Collaborative Evaluation Framework for Biometric Connected Devices in Healthcare.

    Science.gov (United States)

    Farnia, Troskah; Jaulent, Marie Christine; Marchand, Guillaume; Yasini, Mobin

    2017-01-01

    A large number of biometric connected devices are currently available with a variety of designs. Healthcare users cannot easily choose the reliable ones that correspond the best to their healthcare problems. The existing evaluation methods do not consider at the same time aspects of connectivity and healthcare usage. In this study, a collaborative evaluation framework for biometric connected devices in healthcare usage is proposed. This framework contains six dimensions: medical validity, technical reliability, usability, ergonomy, legal compliance, and accuracy of measurements. In a first step, these dimensions were assessed by designing a self administered questionnaire answered by the stakeholders (patients, health professionals, payers, and manufacturers). A case study was then carried out in a second step to test this framework in a project of telemonitoring for heart failure patients. The results are in favor of the efficiency of the proposed framework as a decision making tool in healthcare usage.

  17. Support for system connectivity –Learning from evaluating an evaluation

    DEFF Research Database (Denmark)

    Christensen, Jesper Lindgaard

    been sparse on investigat-ing effects of these as well as on the broader criteria to evaluate the innovation networks and functioning of the system. This paper discusses what are such criteria for evaluating innovation policies that rely on enhanc-ing system connectivity and repair system failures......Innovation is said to be dependent upon collaboration and networks. The innovation system thinking empha-sizes networks but also their supporting informal institutions, learning processes, and the relations between actors in the system. Despite the importance of networks, evaluation studies have......? By way of illustration, and as a mean to be specific on these criteria, the paper discusses the possible rationale for governments to support business angel networks (BAN) and what criteria to apply when evaluating such networks. It is found that applying traditional evaluation criteria for assessing...

  18. Representing connectivity: quantifying effective habitat availability based on area and connectivity for conservation status assessment and recovery.

    Science.gov (United States)

    Neel, Maile; Tumas, Hayley R; Marsden, Brittany W

    2014-01-01

    We apply a comprehensive suite of graph theoretic metrics to illustrate how landscape connectivity can be effectively incorporated into conservation status assessments and in setting conservation objectives. These metrics allow conservation practitioners to evaluate and quantify connectivity in terms of representation, resiliency, and redundancy and the approach can be applied in spite of incomplete knowledge of species-specific biology and dispersal processes. We demonstrate utility of the graph metrics by evaluating changes in distribution and connectivity that would result from implementing two conservation plans for three endangered plant species (Erigeron parishii, Acanthoscyphus parishii var. goodmaniana, and Eriogonum ovalifolium var. vineum) relative to connectivity under current conditions. Although distributions of the species differ from one another in terms of extent and specific location of occupied patches within the study landscape, the spatial scale of potential connectivity in existing networks were strikingly similar for Erigeron and Eriogonum, but differed for Acanthoscyphus. Specifically, patches of the first two species were more regularly distributed whereas subsets of patches of Acanthoscyphus were clustered into more isolated components. Reserves based on US Fish and Wildlife Service critical habitat designation would not greatly contribute to maintain connectivity; they include 83-91% of the extant occurrences and >92% of the aerial extent of each species. Effective connectivity remains within 10% of that in the whole network for all species. A Forest Service habitat management strategy excluded up to 40% of the occupied habitat of each species resulting in both range reductions and loss of occurrences from the central portions of each species' distribution. Overall effective network connectivity was reduced to 62-74% of the full networks. The distance at which each CHMS network first became fully connected was reduced relative to the full

  19. Evaluation of bolted connections in wood-plastic composites

    Science.gov (United States)

    Arnandha, Yudhi; Satyarno, Iman; Awaludin, Ali; Irawati, Inggar Septia; Ihsan, Muhamad; Wijanarko, Felyx Biondy; William, Mahdinur, Fardhani, Arfiati

    2017-03-01

    Wood-plastic composite (WPC) is a relatively new material that consists of sawdust and plastic polymer using the extrusion process. Due to its attributes such as low water content, low maintenance, UV durability and being fungi and termite resistant. Nowadays, WPC has already been produced in Indonesia using sawdust from local wood such as Albizia (Paraserianthes falcataria) and Teak (Tectona grandis). Moreover preliminary studies about the physical and mechanical WPC board from Albizia sawdust and HDPE plastic have been carried out. Based on these studies, WPC has a high shear strength around 25-30 MPa higher than its original wood shear strength. This paper was a part of the research in evaluating WPC as potential sheathing in a shear wall system. Since still little is known about connection behavior in WPC using Indonesian local wood, this study evaluated the connection for both of these two types of wood-plastic composite. WPC board from Albizia sawdust will be projected as shear wall sheathing and WPC stud from Teak sawdust projected to be shear wall frame. For this study, the embedding strength for both WPC was determined according to ASTM D 5764 standard, using two types of bolts (stainless bolt and standard bolt) with several diameters as variation (6 mm, 8 mm, 10 and 12 mm). Hence, dowel-bearing test under fastened condition conducted accordance to ASTM D5652, hereby the yield strength then compared with the prediction yield strength from European Yield Model (EYM). According to both single and double shear connection, it can be concluded that yield strength from the EYM method tended to under-predict the 5% diameter offset yield than the actual yield strength from the test. The yield strength itself increase with the increase of bolt diameter. For single shear connection, the highest yield strength was 12 mm standard bolt around 9732 N, slightly higher than stainless bolt around 9393 N. Whereby for double shear connection, the highest yield strength was

  20. 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

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

    Directory of Open Access Journals (Sweden)

    Demian Battaglia

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

  2. Evaluating the role of river-floodplain connectivity in providing beneficial hydrologic services in mountain landscapes

    Science.gov (United States)

    Covino, T. P.; Wegener, P.; Weiss, T.; Wohl, E.; Rhoades, C.

    2017-12-01

    River networks of mountain landscapes tend to be dominated by steep, valley-confined channels that have limited floodplain area and low hydrologic buffering capacity. Interspersed between the narrow segments are wide, low-gradient segments where extensive floodplains, wetlands, and riparian areas can develop. Although they tend to be limited in their frequency relative to the narrow valley segments, the low-gradient, wide portions of mountain channel networks can be particularly important to hydrologic buffering and can be sites of high nutrient retention and ecosystem productivity. Hydrologic buffering along the wide valley segments is dependent on lateral hydrologic connectivity between the river and floodplain, however these connections have been increasingly severed as a result of various land and water management practices. We evaluated the role of river-floodplain connectivity in influencing water, dissolved organic carbon (DOC), and nutrient flux in river networks of the Colorado Rockies. We found that disconnected segments with limited floodplain/riparian area had limited buffering capacity, while connected segments exhibited variable source-sink dynamics as a function of flow. Specifically, connected segments were typically a sink for water, DOC, and nutrients during high flows, and subsequently became a source as flows decreased. Shifts in river-floodplain hydrologic connectivity across flows related to higher and more variable aquatic ecosystem metabolism rates along connected relative to disconnected segments. Our data suggest that lateral hydrologic connectivity in wide valleys can enhance hydrologic and biogeochemical buffering, and promote high rates of aquatic ecosystem metabolism. While hydrologic disconnection in one river-floodplain system is unlikely to influence water resources at larger scales, the cumulative effects of widespread disconnection may be substantial. Because intact river-floodplain (i.e., connected) systems provide numerous

  3. Fatigue evaluation of piping connections under thermal transients

    International Nuclear Information System (INIS)

    Aquino, C.T.E. de; Maneschy, J.E.

    1993-01-01

    In designing nuclear power plant piping, thermal transients, caused by non-steady operation conditions, should be considered. These events may reduce considerably the lifetime of the pipes, creating the necessity of using structural elements designed in such a way to minimize the acting thermal stresses. Typical examples of the usage of these elements are the connections between pipes of small and large diameters, in which it is usually used a weldolet. Nevertheless, in some situations, the thermal stresses caused by the transients are greater than the allowable limits, being, in this case, an alternative for best results, the introduction of a special fitting replacing the weldolet. Such a fitting is designed in a way to permit a better distribution of the stresses, reducing its maximum value to acceptable levels. This paper intends to present a fatigue evaluation of a connection, using the above mentioned fitting, when subjected to a load expressed in terms of a step thermal gradient, varying from 263 deg to 40 deg C. Two different methodologies are used in this analysis: (a) Determination of the temperature distribution from the heat transfer equations for piping, being the stresses calculated according to ASME III NB-3600. (b) Thermal and stress analyses using axisymmetric elements, according to the rules presented at ASME III NB-3200. In the first case, named simplified analysis, the computer code used is the PIPESTRESS, while in the second case, the ANSYS program was adopted

  4. Investigation of The Effects of Connective Tissue Mobilisation on ...

    African Journals Online (AJOL)

    Background: Connective Tissue Massage (CTM) or Manipulation is a bodywork technique which lies at the interface between alternative approaches. The autonomic balancing responses to CTM can be useful in the treatment of anxiety. Aim: This study was planned to investigate the effects of connective tissue mobilization ...

  5. Evaluation of the Effect of Fixation Angle between Polyaxial Pedicle Screw Head and Rod on the Failure of Screw-Rod Connection

    Directory of Open Access Journals (Sweden)

    Engin Çetin

    2015-01-01

    Full Text Available Introduction. Polyaxial screws had been only tested according to the ASTM standards (when they were perpendicularly positioned to the rod. In this study, effects of the pedicle screws angled fixation to the rod on the mechanical properties of fixation were investigated. Materials and Method. 30 vertically fixed screws and 30 screws fixed with angle were used in the study. Screws were used in three different diameters which were 6.5 mm, 7.0 mm, and 7.5 mm, in equal numbers. Axial pull-out and flexion moment tests were performed. Test results compared with each other using appropriate statistical methods. Results. In pull-out test, vertically fixed screws, in 6.5 mm and 7.0 mm diameter, had significantly higher maximum load values than angled fixed screws with the same diameters (P<0.01. Additionally, vertically fixed screws, in all diameters, had significantly greater stiffness according to corresponding size fixed with angle (P<0.005. Conclusion. Fixing the pedicle screw to the rod with angle significantly decreased the pull-out stiffness in all diameters. Similarly, pedicle screw instrumentation fixed with angle decreased the minimum sagittal angle between the rod and the screw in all diameters for flexion moment test but the differences were not significant.

  6. Thermal fatigue evaluation of piping system Tee-connections

    International Nuclear Information System (INIS)

    Metzner, K.J.; Braillard, O.; Faidy, C.; Marcelles, I.; Solin, J.; Stumpfrock, L.

    2004-01-01

    Thermal fatigue is one significant long-term degradation mechanism nuclear power plants (NPP), in particular, as operating plants become older and life time extension activities have been initiated. In general, the common thermal fatigue issues are understood and controlled by plant instrumentation systems. However, incidents in some plants indicate that certain piping system Tees are susceptible to turbulent temperature mixing effects that cannot be adequately monitored by common thermocouple instrumentation. The THERFAT project has been initiated to advance the accuracy and reliability of thermal fatigue load determination in engineering tools and research oriented approaches to outline a science based practical methodology for managing thermal fatigue risks in Tee-connections susceptible to high cyclic thermal fatigue. (orig.)

  7. Effect of nonlinearity of connecting dampers on vibration control of connected building structures

    Directory of Open Access Journals (Sweden)

    Masatoshi eKasagi

    2016-01-01

    Full Text Available The connection of two building structures with dampers is one of effective vibration control systems. In this vibration control system, both buildings have to possess different vibration properties in order to provide a higher vibration reduction performance. In addition to such condition of different vibration properties of both buildings, the connecting dampers also play an important role in the vibration control mechanism. In this paper, the effect of nonlinearity of connecting dampers on the vibration control of connected building structures is investigated in detail. A high-damping rubber damper and an oil damper with and without relief mechanism are treated. It is shown that, while the high-damping rubber damper is effective in a rather small deformation level, the linear oil damper is effective in a relatively large deformation level. It is further shown that, while the oil dampers reduce the response in the same phase as the case without dampers, the high-damping rubber dampers change the phase. The merit is that the high-damping rubber can reduce the damper deformation and keep the sufficient space between both buildings. This can mitigate the risk of building pounding.

  8. Connect: An Effective Community-Based Youth Suicide Prevention Program

    Science.gov (United States)

    Bean, Gretchen; Baber, Kristine M.

    2011-01-01

    Youth suicide prevention is an important public health issue. However, few prevention programs are theory driven or systematically evaluated. This study evaluated Connect, a community-based youth suicide prevention program. Analysis of pre and posttraining questionnaires from 648 adults and 204 high school students revealed significant changes in…

  9. Different forms of effective connectivity in primate frontotemporal pathways.

    Science.gov (United States)

    Petkov, Christopher I; Kikuchi, Yukiko; Milne, Alice E; Mishkin, Mortimer; Rauschecker, Josef P; Logothetis, Nikos K

    2015-01-23

    It is generally held that non-primary sensory regions of the brain have a strong impact on frontal cortex. However, the effective connectivity of pathways to frontal cortex is poorly understood. Here we microstimulate sites in the superior temporal and ventral frontal cortex of monkeys and use functional magnetic resonance imaging to evaluate the functional activity resulting from the stimulation of interconnected regions. Surprisingly, we find that, although certain earlier stages of auditory cortical processing can strongly activate frontal cortex, downstream auditory regions, such as voice-sensitive cortex, appear to functionally engage primarily an ipsilateral temporal lobe network. Stimulating other sites within this activated temporal lobe network shows strong activation of frontal cortex. The results indicate that the relative stage of sensory processing does not predict the level of functional access to the frontal lobes. Rather, certain brain regions engage local networks, only parts of which have a strong functional impact on frontal cortex.

  10. Effects of local and global network connectivity on synergistic epidemics

    Science.gov (United States)

    Broder-Rodgers, David; Pérez-Reche, Francisco J.; Taraskin, Sergei N.

    2015-12-01

    Epidemics in networks can be affected by cooperation in transmission of infection and also connectivity between nodes. An interplay between these two properties and their influence on epidemic spread are addressed in the paper. A particular type of cooperative effects (called synergy effects) is considered, where the transmission rate between a pair of nodes depends on the number of infected neighbors. The connectivity effects are studied by constructing networks of different topology, starting with lattices with only local connectivity and then with networks that have both local and global connectivity obtained by random bond-rewiring to nodes within a certain distance. The susceptible-infected-removed epidemics were found to exhibit several interesting effects: (i) for epidemics with strong constructive synergy spreading in networks with high local connectivity, the bond rewiring has a negative role in epidemic spread, i.e., it reduces invasion probability; (ii) in contrast, for epidemics with destructive or weak constructive synergy spreading on networks of arbitrary local connectivity, rewiring helps epidemics to spread; (iii) and, finally, rewiring always enhances the spread of epidemics, independent of synergy, if the local connectivity is low.

  11. The Connect Effect Building Strong Personal, Professional, and Virtual Networks

    CERN Document Server

    Dulworth, Michael

    2008-01-01

    Entrepreneur and executive development expert Mike Dulworth's THE CONNECT EFFECT provides readers with a simple framework and practical tools for developing that crucial competitive advantage: a high-quality personal, professional/organizational and virtual network.

  12. Connective tissue diseases and noninvasive evaluation of atherosclerosis

    Directory of Open Access Journals (Sweden)

    Ardita G

    2014-06-01

    Full Text Available Giorgio Ardita, Giacomo Failla, Paolo Maria Finocchiaro, Francesco Mugno, Luigi Attanasio, Salvatore Timineri, Michelangelo Maria Di SalvoCardiovascular Department, Angiology Unit, Ferrarotto Hospital, Catania, ItalyAbstract: Connective tissue diseases (CTDs are associated with increased risk of cardiovascular disease due to accelerated atherosclerosis. In patients with autoimmune disorders, in addition to traditional risk factors, an immune-mediated inflammatory process of the vasculature seems to contribute to atherogenesis. Several pathogenetic mechanisms have been proposed, including chronic inflammation and immunologic abnormalities, both able to produce vascular damage. Macrovascular atherosclerosis can be noninvasively evaluated by ultrasound measurement of carotid or femoral plaque. Subclinical atherosclerosis can be evaluated by well-established noninvasive techniques which rely on ultrasound detection of carotid intima-media thickness. Flow-mediated vasodilatation and arterial stiffness are considered markers of endothelial dysfunction and subclinical atherosclerosis, respectively, and have been recently found to be impaired early in a wide spectrum of autoimmune diseases. Carotid intima-media thickness turns out to be a leading marker of subclinical atherosclerosis, and many studies recognize its role as a predictor of future vascular events, both in non-CTD individuals and in CTD patients. In rheumatic diseases, flow-mediated dilatation and arterial stiffness prove to be strongly correlated with inflammation, disease damage index, and with subclinical atherosclerosis, although their prognostic role has not yet been conclusively shown. Systemic lupus erythematosus, rheumatoid arthritis, and likely antiphospholipid syndrome are better associated with premature and accelerated atherosclerosis. Inconclusive results were reported in systemic sclerosis.Keywords: rheumatic disease, subclinical atherosclerosis, arterial stiffness

  13. Effects of Auxiliary-Source Connection in Multichip Power Module

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Wang, Xiongfei

    2017-01-01

    the power loop and the gate loop like how the Kelvin-source connection does, owing to their involvement in the loop of the power source current. Three effects of the auxiliary-source connections are then analyzed, which are 1) the common source stray inductance reduction, 2) the transient drain......Auxiliary-source bond wires and connections are widely used in power modules with paralleled MOSFETs or IGBTs. This paper investigates the operation mechanism of the auxiliary-source connections in multichip power modules. It reveals that the auxiliary-source connections cannot fully decouple......-source current imbalance mitigation, and 3) the influence on the steady-state current distribution. Lastly, simulations and experimental results validate the theoretical analysis....

  14. Laterality patterns of brain functional connectivity: gender effects.

    Science.gov (United States)

    Tomasi, Dardo; Volkow, Nora D

    2012-06-01

    Lateralization of brain connectivity may be essential for normal brain function and may be sexually dimorphic. Here, we study the laterality patterns of short-range (implicated in functional specialization) and long-range (implicated in functional integration) connectivity and the gender effects on these laterality patterns. Parallel computing was used to quantify short- and long-range functional connectivity densities in 913 healthy subjects. Short-range connectivity was rightward lateralized and most asymmetrical in areas around the lateral sulcus, whereas long-range connectivity was rightward lateralized in lateral sulcus and leftward lateralizated in inferior prefrontal cortex and angular gyrus. The posterior inferior occipital cortex was leftward lateralized (short- and long-range connectivity). Males had greater rightward lateralization of brain connectivity in superior temporal (short- and long-range), inferior frontal, and inferior occipital cortices (short-range), whereas females had greater leftward lateralization of long-range connectivity in the inferior frontal cortex. The greater lateralization of the male's brain (rightward and predominantly short-range) may underlie their greater vulnerability to disorders with disrupted brain asymmetries (schizophrenia, autism).

  15. The "Mozart Effect" and the Mathematical Connection

    Science.gov (United States)

    Taylor, Judy M.; Rowe, Beverly J.

    2012-01-01

    Educators are always looking for ways to enhance the performance of students on outcome assessments. There is a growing body of research showing the benefits of music on educational performance. The purpose of this study was to determine if a "Mozart Effect" improves student performance on outcome assessments in mathematics. In this study, during…

  16. Connectivity effects in the dynamic model of neural networks

    International Nuclear Information System (INIS)

    Choi, J; Choi, M Y; Yoon, B-G

    2009-01-01

    We study, via extensive Monte Carlo calculations, the effects of connectivity in the dynamic model of neural networks, to observe that the Mattis-state order parameter increases with the number of coupled neurons. Such effects appear more pronounced when the average number of connections is increased by introducing shortcuts in the network. In particular, the power spectra of the order parameter at stationarity are found to exhibit power-law behavior, depending on how the average number of connections is increased. The cluster size distribution of the 'memory-unmatched' sites also follows a power law and possesses strong correlations with the power spectra. It is further observed that the distribution of waiting times for neuron firing fits roughly to a power law, again depending on how neuronal connections are increased

  17. Brain Connectivity Studies in Schizophrenia: Unravelling the Effects of Antipsychotics

    DEFF Research Database (Denmark)

    Nejad, A.B.; Ebdrup, Bjørn Hylsebeck; Glenthøj, Birte Yding

    2012-01-01

    Impaired brain connectivity is a hallmark of schizophrenia brain dysfunction. However, the effect of drug treatment and challenges on the dysconnectivity of functional networks in schizophrenia is an understudied area. In this review, we provide an overview of functional magnetic resonance imaging...... studies examining dysconnectivity in schizophrenia and discuss the few studies which have also attempted to probe connectivity changes with antipsychotic drug treatment. We conclude with a discussion of possible avenues for further investigation....

  18. Connected Vehicle Pilot Deployment Program Independent Evaluation: Mobility, Environmental, and Public Agency Efficiency Refined Evaluation Plan - New York City

    Science.gov (United States)

    2018-03-01

    The purpose of this report is to provide a refined evaluation plan detailing the approach to be used by the Texas A&M Transportation Institute Connected Vehicle Pilot Deployment Evaluation Team for evaluating the mobility, environmental, and public a...

  19. Seismic Performance Evaluation of Steel Moment Resisting Frames with WUF-B Connections

    International Nuclear Information System (INIS)

    Moon, Ki-Hoon; Han, Sang-Whan

    2008-01-01

    The purpose of this study is to evaluate the seismic performance of the moment resisting steel frames having Welded Unreinforced Flange-Bolted web (WUF-B) connections. The connections are designed and detailed in compliance with FEMA 350 recommended seismic design criteria. To conduct the seismic performance evaluation this study developed an analytical model for the pre- and post-Northridge connections based on test results. Three different frames are considered which have three-, nine- and twenty-story. Incremental Dynamic Analysis (IDA is conducted to estimate limit state capacities The performance of the frames having either pre- or post-Northridge connections is compared with the corresponding frame with ductile connections which do not experience connection fracture. The analytical results showed that buildings with post-Northridge WUF-B connections provide superior strength and interstory drift ratio capacity than buildings with pre-Northridge WUF-B connections

  20. Metabolic connectivity mapping reveals effective connectivity in the resting human brain.

    Science.gov (United States)

    Riedl, Valentin; Utz, Lukas; Castrillón, Gabriel; Grimmer, Timo; Rauschecker, Josef P; Ploner, Markus; Friston, Karl J; Drzezga, Alexander; Sorg, Christian

    2016-01-12

    Directionality of signaling among brain regions provides essential information about human cognition and disease states. Assessing such effective connectivity (EC) across brain states using functional magnetic resonance imaging (fMRI) alone has proven difficult, however. We propose a novel measure of EC, termed metabolic connectivity mapping (MCM), that integrates undirected functional connectivity (FC) with local energy metabolism from fMRI and positron emission tomography (PET) data acquired simultaneously. This method is based on the concept that most energy required for neuronal communication is consumed postsynaptically, i.e., at the target neurons. We investigated MCM and possible changes in EC within the physiological range using "eyes open" versus "eyes closed" conditions in healthy subjects. Independent of condition, MCM reliably detected stable and bidirectional communication between early and higher visual regions. Moreover, we found stable top-down signaling from a frontoparietal network including frontal eye fields. In contrast, we found additional top-down signaling from all major clusters of the salience network to early visual cortex only in the eyes open condition. MCM revealed consistent bidirectional and unidirectional signaling across the entire cortex, along with prominent changes in network interactions across two simple brain states. We propose MCM as a novel approach for inferring EC from neuronal energy metabolism that is ideally suited to study signaling hierarchies in the brain and their defects in brain disorders.

  1. Performance Evaluation of Moment Connections of Moment Resisting Frames Against Progressive Collapse

    Directory of Open Access Journals (Sweden)

    M. Mahmoudi

    2017-02-01

    Full Text Available When a primary structural element fails due to sudden load such as explosion, the building undergoes progressive collapse. The method for design of moment connections during progressive collapse is different to seismic design of moment connections. Because in this case, the axial force on the connections makes it behave differently. The purpose of this paper is to evaluate the performance of a variety of moment connections in preventing progressive collapse in steel moment frames. To achieve this goal, three prequalified moment connections (BSEEP, BFP and WUP-W were designed according seismic codes. These moment connections were analyzed numerically using ABAQUS software for progressive collapse. The results show that the BFP connection (bolted flange plate has capacity much more than other connections because of the use of plates at the junction of beam-column.

  2. A new method to evaluate the sealing reliability of the flanged connections for Molten Salt Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qiming, E-mail: liqiming@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Chinese Academy of Sciences, Shanghai 201800 (China); Tian, Jian; Zhou, Chong [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Chinese Academy of Sciences, Shanghai 201800 (China); Wang, Naxiu, E-mail: wangnaxiu@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Chinese Academy of Sciences, Shanghai 201800 (China)

    2015-06-15

    Highlights: • We novelly valuate the sealing reliability of the flanged connections for MSRs. • We focus on the passive decrease of the leak impetus in flanged connections. • The modified flanged connections are acquired a sealing ability of self-adjustment. • Effects of redesigned flange configurations on molten salt leakage are discussed. - Abstract: The Thorium based Molten Salt Reactor (TMSR) project is a future Generation IV nuclear reactor system proposed by the Chinese Academy of Sciences with the strategic goal of meeting the growing energy needs in the Chinese economic development and social progress. It is based on liquid salts served as both fuel and primary coolant and consequently great challenges are brought into the sealing of the flanged connections. In this study, an improved prototype flange assembly is performed on the strength of the Freeze-Flange initially developed by Oak Ridge National Laboratory (ORNL). The calculation results of the finite element model established to analyze the temperature profile of the Freeze-Flange agree well with the experimental data, which indicates that the numerical simulation method is credible. For further consideration, the ideal-gas thermodynamic model, together with the mathematical approximation, is novelly borrowed to theoretically evaluate the sealing performance of the modified Freeze-Flange and the traditional double gaskets bolted flange joint. This study focuses on the passive decrease of the leak driving force due to multiple gaskets introduced in flanged connections for MSR. The effects of the redesigned flange configuration on molten salt leakage resistance are discussed in detail.

  3. A new method to evaluate the sealing reliability of the flanged connections for Molten Salt Reactors

    International Nuclear Information System (INIS)

    Li, Qiming; Tian, Jian; Zhou, Chong; Wang, Naxiu

    2015-01-01

    Highlights: • We novelly valuate the sealing reliability of the flanged connections for MSRs. • We focus on the passive decrease of the leak impetus in flanged connections. • The modified flanged connections are acquired a sealing ability of self-adjustment. • Effects of redesigned flange configurations on molten salt leakage are discussed. - Abstract: The Thorium based Molten Salt Reactor (TMSR) project is a future Generation IV nuclear reactor system proposed by the Chinese Academy of Sciences with the strategic goal of meeting the growing energy needs in the Chinese economic development and social progress. It is based on liquid salts served as both fuel and primary coolant and consequently great challenges are brought into the sealing of the flanged connections. In this study, an improved prototype flange assembly is performed on the strength of the Freeze-Flange initially developed by Oak Ridge National Laboratory (ORNL). The calculation results of the finite element model established to analyze the temperature profile of the Freeze-Flange agree well with the experimental data, which indicates that the numerical simulation method is credible. For further consideration, the ideal-gas thermodynamic model, together with the mathematical approximation, is novelly borrowed to theoretically evaluate the sealing performance of the modified Freeze-Flange and the traditional double gaskets bolted flange joint. This study focuses on the passive decrease of the leak driving force due to multiple gaskets introduced in flanged connections for MSR. The effects of the redesigned flange configuration on molten salt leakage resistance are discussed in detail

  4. Effects of matrix characteristics and interpatch distance on functional connectivity in fragmented temperate rainforests.

    Science.gov (United States)

    Magrach, Ainhoa; Larrinaga, Asier R; Santamaría, Luis

    2012-04-01

    The connectivity of remnant patches of habitat may affect the persistence of species in fragmented landscapes. We evaluated the effects of the structural connectivity of forest patches (i.e., distance between patches) and matrix class (land-cover type) on the functional connectivity of 3 bird species (the White-crested Elaenia [Elaenia albiceps], the Green-backed Firecrown Hummingbird [Sephanoides sephaniodes], and the Austral Thrush [Turdus falklandii]). We measured functional connectivity as the rate at which each species crossed from one patch to another. We also evaluated whether greater functional connectivity translated into greater ecological connectivity (dispersal of fruit and pollen) by comparing among forest patches fruit set of a plant pollinated by hummingbirds and abundance of seedlings and adults of 2 plants with bird- and wind-dispersed seeds. Interpatch distance was strongly associated with functional connectivity, but its effect was not independent of matrix class. For one of the bird-dispersed plants, greater functional connectivity for White-crested Elaenias and Austral Thrushes (both frugivores) was associated with higher densities of this plant. The lack of a similar association for the wind-dispersed species suggests this effect is linked to the dispersal vector. The abundance of the hummingbird-pollinated species was not related to the presence of hummingbirds. Interpatch distance and matrix class affect animal movement in fragmented landscapes and may have a cascading effect on the distribution of some animal-dispersed species. On the basis of our results, we believe effort should be invested in optimizing patch configuration and modifying the matrix so as to mitigate the effects of patch isolation in fragmented landscapes. ©2012 Society for Conservation Biology.

  5. 26 CFR 1.996-6 - Effectively connected income.

    Science.gov (United States)

    2010-04-01

    ....996-6 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Domestic International Sales Corporations § 1.996-6 Effectively connected income. In... permanent establishment of such shareholder within the United States, and shall be subject to tax in...

  6. Evaluating Landscape Connectivity for Puma concolor and Panthera onca Among Atlantic Forest Protected Areas

    Science.gov (United States)

    Castilho, Camila S.; Hackbart, Vivian C. S.; Pivello, Vânia R.; dos Santos, Rozely F.

    2015-06-01

    Strictly Protected Areas and riparian forests in Brazil are rarely large enough or connected enough to maintain viable populations of carnivores and animal movement over time, but these characteristics are fundamental for species conservation as they prevent the extinction of isolated animal populations. Therefore, the need to maintain connectivity for these species in human-dominated Atlantic landscapes is critical. In this study, we evaluated the landscape connectivity for large carnivores (cougar and jaguar) among the Strictly Protected Areas in the Atlantic Forest, evaluated the efficiency of the Mosaics of Protected Areas linked to land uses in promoting landscape connectivity, identified the critical habitat connections, and predicted the landscape connectivity status under the implementation of legislation for protecting riparian forests. The method was based on expert opinion translated into land use and land cover maps. The results show that the Protected Areas are still connected by a narrow band of landscape that is permeable to both species and that the Mosaics of Protected Areas increase the amount of protected area but fail to increase the connectivity between the forested mountain ranges (Serra do Mar and Serra da Mantiqueira). Riparian forests greatly increase connectivity, more than tripling the cougars' priority areas. We note that the selection of Brazilian protected areas still fails to create connectivity among the legally protected forest remnants. We recommend the immediate protection of the priority areas identified that would increase the structural landscape connectivity for these large carnivores, especially paths in the SE/NW direction between the two mountain ranges.

  7. Evaluating Landscape Connectivity for Puma concolor and Panthera onca Among Atlantic Forest Protected Areas.

    Science.gov (United States)

    Castilho, Camila S; Hackbart, Vivian C S; Pivello, Vânia R; dos Santos, Rozely F

    2015-06-01

    Strictly Protected Areas and riparian forests in Brazil are rarely large enough or connected enough to maintain viable populations of carnivores and animal movement over time, but these characteristics are fundamental for species conservation as they prevent the extinction of isolated animal populations. Therefore, the need to maintain connectivity for these species in human-dominated Atlantic landscapes is critical. In this study, we evaluated the landscape connectivity for large carnivores (cougar and jaguar) among the Strictly Protected Areas in the Atlantic Forest, evaluated the efficiency of the Mosaics of Protected Areas linked to land uses in promoting landscape connectivity, identified the critical habitat connections, and predicted the landscape connectivity status under the implementation of legislation for protecting riparian forests. The method was based on expert opinion translated into land use and land cover maps. The results show that the Protected Areas are still connected by a narrow band of landscape that is permeable to both species and that the Mosaics of Protected Areas increase the amount of protected area but fail to increase the connectivity between the forested mountain ranges (Serra do Mar and Serra da Mantiqueira). Riparian forests greatly increase connectivity, more than tripling the cougars' priority areas. We note that the selection of Brazilian protected areas still fails to create connectivity among the legally protected forest remnants. We recommend the immediate protection of the priority areas identified that would increase the structural landscape connectivity for these large carnivores, especially paths in the SE/NW direction between the two mountain ranges.

  8. Estimation of effective brain connectivity with dual Kalman filter and EEG source localization methods.

    Science.gov (United States)

    Rajabioun, Mehdi; Nasrabadi, Ali Motie; Shamsollahi, Mohammad Bagher

    2017-09-01

    Effective connectivity is one of the most important considerations in brain functional mapping via EEG. It demonstrates the effects of a particular active brain region on others. In this paper, a new method is proposed which is based on dual Kalman filter. In this method, firstly by using a brain active localization method (standardized low resolution brain electromagnetic tomography) and applying it to EEG signal, active regions are extracted, and appropriate time model (multivariate autoregressive model) is fitted to extracted brain active sources for evaluating the activity and time dependence between sources. Then, dual Kalman filter is used to estimate model parameters or effective connectivity between active regions. The advantage of this method is the estimation of different brain parts activity simultaneously with the calculation of effective connectivity between active regions. By combining dual Kalman filter with brain source localization methods, in addition to the connectivity estimation between parts, source activity is updated during the time. The proposed method performance has been evaluated firstly by applying it to simulated EEG signals with interacting connectivity simulation between active parts. Noisy simulated signals with different signal to noise ratios are used for evaluating method sensitivity to noise and comparing proposed method performance with other methods. Then the method is applied to real signals and the estimation error during a sweeping window is calculated. By comparing proposed method results in different simulation (simulated and real signals), proposed method gives acceptable results with least mean square error in noisy or real conditions.

  9. A GIS BASED EVALUATION OF LAND USE CHANGES AND ECOLOGICAL CONNECTIVITY INDEX

    Directory of Open Access Journals (Sweden)

    Poppy Indrayani

    2017-03-01

    Full Text Available Recently, the Makassar region is a significant land use planning and management issue, and has many impacts on the ecological function and structure landscape. With the development and infrastructure initiatives mostly around the urban centers, the urbanization and sprawl would impact the environment and the natural resources. Therefore, environmental management and careful strategic spatial planning in landscape ecological network is crucial when aiming for sustainable development. In this paper, the impacts of land use changes from 1997 to 2012 on the landscape ecological connectivity in the Makassar region were evaluated using Geographic Information System (GIS. The resulted GIS analysis clearly showed that land use changes occurring in the Makassar region have caused profound changes in landscape pattern. The spatial model had a predictive capability allowing the quantitative assessment and comparison of the impacts resulting from different land use on the ecological connectivity index. The results had an effective performance in identifying the vital ecological areas and connectivity prior to development plan in areas.

  10. The role of connective tissue in late effects of radiation

    International Nuclear Information System (INIS)

    Gerber, G.B.

    1979-01-01

    Connective tissues not only serve as support, but also filter and censor the physical and molecular information reaching cells. The late change in connective tissues, i.e. fibrosis several months or years after the irradiation with 1000 rad or more, has been well known, and the dreaded sequel of radiation therapy, but connective tissues are affected already at much earlier time. The change in irradiated connective tissues may be distinguished in 3 phases after irradiation, the change in permeability within hours, damage to cell replacement systems within days and months and the late change of fibrosis, vascular damage and parenchymal atrophy after months and years. Glomerular sclerosis, tubular atrophy and interstitial fibrosis after the excessive irradiation of kidneys, accompanied by renal failure and hypertension, are usually considered as the consequence of vascular or tubular damage, but recent investigation suggested that the change in blood flow is correlated also with the increase in collagen, so that fibrosis may represent an important factor in the pathogenesis of renal damage. Radiofibrosis is considered simply as a result of the vascular damage due to the deficient or abnormal replacement of endothelial cells and/or due to arteriolo-capillary fibrosis. The late effects depend on early ones, and the endothelial cells would be only one. Other possible paths could depend on low fibrinolytic activity and immunological reactions. (Yamashita, S.)

  11. An evaluation method of power quality about electrified railways connected to power grid based on PSCAD/EMTDC

    Science.gov (United States)

    Liang, Weibin; Ouyang, Sen; Huang, Xiang; Su, Weijian

    2017-05-01

    The existing modeling process of power quality about electrified railways connected to power grid is complicated and the simulation scene is incomplete, so this paper puts forward a novel evaluation method of power quality based on PSCAD/ETMDC. Firstly, a model of power quality about electrified railways connected to power grid is established, which is based on testing report or measured data. The equivalent model of electrified locomotive contains power characteristic and harmonic characteristic, which are substituted by load and harmonic source. Secondly, in order to make evaluation more complete, an analysis scheme has been put forward. The scheme uses a combination of three-dimensions of electrified locomotive, which contains types, working conditions and quantity. At last, Shenmao Railway is taken as example to evaluate the power quality at different scenes, and the result shows electrified railways connected to power grid have significant effect on power quality.

  12. The Comprehensive Benefit Evaluation of Take Shared Bicycles as Connecting to Public Transit

    Science.gov (United States)

    Zhang, J. Y.; Sun, H.; Li, P. F.; Li, C. C.

    2017-10-01

    Shared bicycles as an important way of connecting public transport, have few literature to evaluate its effectiveness.This paper taking Beijing city as an example, make anevaluationfor the six types of travel combinations which are commonly used by the citizens. The author selects four quantitative indicators: fuel consumption, economic cost, total time spent, and CO2 emission. And two qualitative indicators: degree of comfort and convenience. The relative efficiency of quantitative indicators is obtained by data envelopment analysis (DEA) and fuzzification and then take fuzzy synthetic evaluation with qualitative indicators.It was found that the choice of shared bicycles +subway+ shared bicycles and shared bicycles has good comprehensive benefits in medium distance travel. The findings also suggest that shared bicycles +subway+ shared bicycles is the best choice in the utilitarian trips. The conclusions not only provide suggestions for the travellers to select travel modes, but also can adjust the relevant factors to increase the proportion of green travel.

  13. Evaluating population connectivity for species of conservation concern in the American Great Plains

    Science.gov (United States)

    Samuel A. Cushman; Erin L. Landguth; Curtis H. Flather

    2013-01-01

    Habitat loss and fragmentation are widely recognized as among the most important threats to global biodiversity. New analytical approaches are providing an improved ability to predict the effects of landscape change on population connectivity at vast spatial extents. This paper presents an analysis of population connectivity for three species of conservation concern [...

  14. Ultrastructural evaluation of gingival connective tissue in hereditary gingival fibromatosis.

    Science.gov (United States)

    Pêgo, Sabina Pena B; de Faria, Paulo Rogério; Santos, Luis Antônio N; Coletta, Ricardo D; de Aquino, Sibele Nascimento; Martelli-Júnior, Hercílio

    2016-07-01

    To describe the ultrastructural features of hereditary gingival fibromatosis (HGF) in affected family members and compare microscopic findings with normal gingival (NG) tissue. Gingival tissue samples from nine patients with HGF from five unrelated families were evaluated by transmission electron microscopy. Nine NG tissue samples were used for comparison. Areas containing collagen fibrils forming loops and folds were observed in both groups, whereas oxytalan fibers were frequently identified in the HGF group. The diameter of collagen fibrils and the interfibrillar space among them were more uniform in the NG group than in the HGF group. Fibroblasts were the most common cells found in both the HGF and NG groups and exhibited enlarged, rough endoplasmic reticulum, mitochondria with well-preserved crests, conspicuous nucleoli, and euchromatic chromatin. Other cells, such as mast cells, plasma cells, and macrophages, were also observed. HGF tissues had ultrastructural characteristics that were very similar to those of NG tissues. Oxytalan fibers were observed more frequently in the HGF samples than in the NG samples. Other studies of HGF in patients from different families should be performed to better understand the pathogenesis of this hereditary condition. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Sex differences in effective fronto-limbic connectivity during negative emotion processing.

    Science.gov (United States)

    Lungu, Ovidiu; Potvin, Stéphane; Tikàsz, Andràs; Mendrek, Adrianna

    2015-12-01

    In view of the greater prevalence of depression and anxiety disorders in women than in men, functional magnetic resonance imaging (fMRI) studies have examined sex-differences in brain activations during emotion processing. Comparatively, sex-differences in brain connectivity received little attention, despite evidence for important fronto-limbic connections during emotion processing across sexes. Here, we investigated sex-differences in fronto-limbic connectivity during negative emotion processing. Forty-six healthy individuals (25 women, 21 men) viewed negative, positive and neutral images during an fMRI session. Effective connectivity between significantly activated regions was examined using Granger causality and psychophysical interaction analyses. Sex steroid hormones and feminine-masculine traits were also measured. Subjective ratings of negative emotional images were higher in women than in men. Across sexes, significant activations were observed in the dorso-medial prefrontal cortex (dmPFC) and the right amygdala. Granger connectivity from right amygdala was significantly greater than that from dmPFC during the 'high negative' condition, an effect driven by men. Magnitude of this effect correlated negatively with highly negative image ratings and feminine traits and positively with testosterone levels. These results highlight critical sex differences in brain connectivity during negative emotion processing and point to the fact that both biological (sex steroid hormones) and psychosocial (gender role and identity) variables contribute to them. As the dmPFC is involved in social cognition and action planning, and the amygdala-in threat detection, the connectivity results suggest that compared to women, men have a more evaluative, rather than purely affective, brain response during negative emotion processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Interwell Connectivity Evaluation Using Injection and Production Fluctuation Data

    Science.gov (United States)

    Shang, Barry Zhongqi

    The development of multiscale methods for computational simulation of biophysical systems represents a significant challenge. Effective computational models that bridge physical insights obtained from atomistic simulations and experimental findings are lacking. An accurate passing of information between these scales would enable: (1) an improved physical understanding of structure-function relationships, and (2) enhanced rational strategies for molecular engineering and materials design. Two approaches are described in this dissertation to facilitate these multiscale goals. In Part I, we develop a lattice kinetic Monte Carlo model to simulate cellulose decomposition by cellulase enzymes and to understand the effects of spatial confinement on enzyme kinetics. An enhanced mechanistic understanding of this reaction system could enhance the design of cellulose bioconversion technologies for renewable and sustainable energy. Using our model, we simulate the reaction up to experimental conversion times of days, while simultaneously capturing the microscopic kinetic behaviors. Therefore, the influence of molecular-scale kinetics on the macroscopic conversion rate is made transparent. The inclusion of spatial constraints in the kinetic model represents a significant advance over classical mass-action models commonly used to describe this reaction system. We find that restrictions due to enzyme jamming and substrate heterogeneity at the molecular level play a dominate role in limiting cellulose conversion. We identify that the key rate limitations are the slow rates of enzyme complexation with glucan chains and the competition between enzyme processivity and jamming. We show that the kinetics of complexation, which involves extraction of a glucan chain end from the cellulose surface and threading through the enzyme active site, occurs slowly on the order of hours, while intrinsic hydrolytic bond cleavage occurs on the order of seconds. We also elucidate the subtle trade

  17. Effective connectivity reveals strategy differences in an expert calculator.

    Directory of Open Access Journals (Sweden)

    Ludovico Minati

    Full Text Available Mathematical reasoning is a core component of cognition and the study of experts defines the upper limits of human cognitive abilities, which is why we are fascinated by peak performers, such as chess masters and mental calculators. Here, we investigated the neural bases of calendrical skills, i.e. the ability to rapidly identify the weekday of a particular date, in a gifted mental calculator who does not fall in the autistic spectrum, using functional MRI. Graph-based mapping of effective connectivity, but not univariate analysis, revealed distinct anatomical location of "cortical hubs" supporting the processing of well-practiced close dates and less-practiced remote dates: the former engaged predominantly occipital and medial temporal areas, whereas the latter were associated mainly with prefrontal, orbitofrontal and anterior cingulate connectivity. These results point to the effect of extensive practice on the development of expertise and long term working memory, and demonstrate the role of frontal networks in supporting performance on less practiced calculations, which incur additional processing demands. Through the example of calendrical skills, our results demonstrate that the ability to perform complex calculations is initially supported by extensive attentional and strategic resources, which, as expertise develops, are gradually replaced by access to long term working memory for familiar material.

  18. Effective connectivity of visual word recognition and homophone orthographic errors

    Science.gov (United States)

    Guàrdia-Olmos, Joan; Peró-Cebollero, Maribel; Zarabozo-Hurtado, Daniel; González-Garrido, Andrés A.; Gudayol-Ferré, Esteve

    2015-01-01

    The study of orthographic errors in a transparent language like Spanish is an important topic in relation to writing acquisition. The development of neuroimaging techniques, particularly functional magnetic resonance imaging (fMRI), has enabled the study of such relationships between brain areas. The main objective of the present study was to explore the patterns of effective connectivity by processing pseudohomophone orthographic errors among subjects with high and low spelling skills. Two groups of 12 Mexican subjects each, matched by age, were formed based on their results in a series of ad hoc spelling-related out-scanner tests: a high spelling skills (HSSs) group and a low spelling skills (LSSs) group. During the f MRI session, two experimental tasks were applied (spelling recognition task and visuoperceptual recognition task). Regions of Interest and their signal values were obtained for both tasks. Based on these values, structural equation models (SEMs) were obtained for each group of spelling competence (HSS and LSS) and task through maximum likelihood estimation, and the model with the best fit was chosen in each case. Likewise, dynamic causal models (DCMs) were estimated for all the conditions across tasks and groups. The HSS group’s SEM results suggest that, in the spelling recognition task, the right middle temporal gyrus, and, to a lesser extent, the left parahippocampal gyrus receive most of the significant effects, whereas the DCM results in the visuoperceptual recognition task show less complex effects, but still congruent with the previous results, with an important role in several areas. In general, these results are consistent with the major findings in partial studies about linguistic activities but they are the first analyses of statistical effective brain connectivity in transparent languages. PMID:26042070

  19. Proactively evaluating training effectiveness

    International Nuclear Information System (INIS)

    Fetterman, Harry E.

    2003-01-01

    A common model of the five phase Systematic Approach to Training (SAT) displays the fifth phase, evaluation, feeding back into the previous four phases: analysis, design, development, and implementation. Evaluating training effectiveness in PP and L's Nuclear Department is not simply the fifth phase of the SAT. PP and L has demonstrated a more effective methodology is realized when evaluation is built into each of the other four phases. At PP and L, evaluation is conducted formatively throughout the first four phases of the SAT process and summatively after implementation. (author)

  20. Evaluation of cooperation WPP and PV connected through the shared transformer to the network 22kV

    Directory of Open Access Journals (Sweden)

    Tomas Sumbera

    2012-01-01

    Full Text Available The article deals with evaluation the cooperation possibility of wind and solar power plants connected through the common transformator to the 22kV network. Cooperation evaluation is, based on measured data, for wind power plant about installed capacity 2MW and for solar power plant about installed capacity 1,1MWp. In the next part of this article there is the analysis of suitable localities for construction of „hybrid system (WPP+PV“ in the Czech Republic. The last part of the article deals with analysis of active power fluctuation of individuals electric sources compared with system WPP+PV and with evaluation the effects after system connection WPP+PV to the 22kV network.

  1. Climate effects on the distribution of wetland habitats and connectivity in networks of migratory waterbirds

    Science.gov (United States)

    Bellisario, Bruno; Cerfolli, Fulvio; Nascetti, Giuseppe

    2014-07-01

    The establishment and maintenance of conservation areas are among the most common measures to mitigate the loss of biodiversity. However, recent advances in conservation biology have challenged the reliability of such areas to cope with variation in climate conditions. Climate change can reshuffle the geographic distribution of species, but in many cases suitable habitats become scarce or unavailable, limiting the ability to migrate or adapt in response to modified environments. In this respect, the extent to which existing protected areas are able to compensate changes in habitat conditions to ensure the persistence of species still remains unclear. We used a spatially explicit model to measure the effects of climate change on the potential distribution of wetland habitats and connectivity of Natura 2000 sites in Italy. The effects of climate change were measured on the potential for water accumulation in a given site, as a surrogate measure for the persistence of aquatic ecosystems and their associated migratory waterbirds. Climate impacts followed a geographic trend, changing the distribution of suitable habitats for migrants and highlighting a latitudinal threshold beyond which the connectivity reaches a sudden collapse. Our findings show the relative poor reliability of most sites in dealing with changing habitat conditions and ensure the long-term connectivity, with possible consequences for the persistence of species. Although alterations of climate suitability and habitat destruction could impact critical areas for migratory waterbirds, more research is needed to evaluate all possible long-term effects on the connectivity of migratory networks.

  2. [Nailfold capillaroscopy in the evaluation of Raynaud's phenomenon and undifferentiated connective tissue disease].

    Science.gov (United States)

    Cortes, Sara; Clemente-Coelho, Paulo

    2008-01-01

    Microvascular abnormalities involved in the pathogenic mechanism of several connective tissue disorders can be detected by nailfold capillaroscopy. Evaluation of the interest of nailfold capillaroscopy results in patients with Raynaud s phenomenon or undifferentiated connective tissue disease and their correlation with diagnostic and therapeutical evolution. Selection of capillaroscopic and laboratory results of patients with the diagnosis of Raynaud s phenomenon (without defined connective tissue disease) or undifferentiated connective tissue disease. Evaluation of the present diagnosis and treatment comparing with the ones existed at the time of capillaroscopy performance. 80 patients were enrolled with an age of 51.4+/-14.3 years (mean+/-SD) 78 females (97.5%) with Raynaud s phenomenon and undifferentiated connective tissue disease 27 patients (33.8%); Raynaud s Phenomenon 46 patients (57.5%); undifferentiated connective tissue disease 7 patients (8.7%). The capillaroscopic results were normal 30 patients (37.5%); minor changes tortuosity enlargement 16 patients (20.0%) major changes 34 patients (42.5%) hemorrhages 25 patients (31.3%) megacapillaries 26 patients (32.5%) avascular areas 3 patients (3.8%). The introduction of new treatments after the capillaroscopy occurred in 32 patients (40.0%) and a new diagnosis was done in 39 patients (48.8%). Major changes in capillaroscopy correlated with the change of diagnosis and the introduction of a new treatment (pNailfold capillaroscopy performed in patients with isolated Raynaud s phenomenon or undifferentiated connective tissue disease has a role in the prognostic evaluation related to the possibility of an evolution of the diagnosis or to the need of the introduction of new treatments.

  3. Training effectiveness evaluation model

    International Nuclear Information System (INIS)

    Penrose, J.B.

    1993-01-01

    NAESCO's Training Effectiveness Evaluation Model (TEEM) integrates existing evaluation procedures with new procedures. The new procedures are designed to measure training impact on organizational productivity. TEEM seeks to enhance organizational productivity through proactive training focused on operation results. These results can be identified and measured by establishing and tracking performance indicators. Relating training to organizational productivity is not easy. TEEM is a team process. It offers strategies to assess more effectively organizational costs and benefits of training. TEEM is one organization's attempt to refine, manage and extend its training evaluation program

  4. Evaluation of phenoxybenzamine in the CFA model of pain following gene expression studies and connectivity mapping.

    Science.gov (United States)

    Chang, Meiping; Smith, Sarah; Thorpe, Andrew; Barratt, Michael J; Karim, Farzana

    2010-09-16

    We have previously used the rat 4 day Complete Freund's Adjuvant (CFA) model to screen compounds with potential to reduce osteoarthritic pain. The aim of this study was to identify genes altered in this model of osteoarthritic pain and use this information to infer analgesic potential of compounds based on their own gene expression profiles using the Connectivity Map approach. Using microarrays, we identified differentially expressed genes in L4 and L5 dorsal root ganglia (DRG) from rats that had received intraplantar CFA for 4 days compared to matched, untreated control animals. Analysis of these data indicated that the two groups were distinguishable by differences in genes important in immune responses, nerve growth and regeneration. This list of differentially expressed genes defined a "CFA signature". We used the Connectivity Map approach to identify pharmacologic agents in the Broad Institute Build02 database that had gene expression signatures that were inversely related ('negatively connected') with our CFA signature. To test the predictive nature of the Connectivity Map methodology, we tested phenoxybenzamine (an alpha adrenergic receptor antagonist) - one of the most negatively connected compounds identified in this database - for analgesic activity in the CFA model. Our results indicate that at 10 mg/kg, phenoxybenzamine demonstrated analgesia comparable to that of Naproxen in this model. Evaluation of phenoxybenzamine-induced analgesia in the current study lends support to the utility of the Connectivity Map approach for identifying compounds with analgesic properties in the CFA model.

  5. Evaluating the sufficiency of protected lands for maintaining wildlife population connectivity in the northern Rocky Mountains

    Science.gov (United States)

    Samuel A. Cushman; Erin L. Landguth; Curtis H. Flather

    2012-01-01

    Aim: The goal of this study was to evaluate the sufficiency of the network of protected lands in the U.S. northern Rocky Mountains in providing protection for habitat connectivity for 105 hypothetical organisms. A large proportion of the landscape...

  6. The evaluation of collagen gel with various connection states by using MRI

    International Nuclear Information System (INIS)

    Kudo, Hiroki; Mukai, Naoki; Gouping, Chen; Numanno, Tomokazu; Honma, Kazuhiro; Tateishi, Tetsuya; Miyanaga, Yutaka; Miyakawa, Syumpei

    2008-01-01

    To noninvasively evaluate the connection states of collagen fiber, a characterizing factor of the physical property, is considered to be helpful in the evaluation of cartilage functions. The purpose of this study was to examine how the connection states of collagen influence the MRI parameters by evaluating the collagen gel with various connection states using MRI. MRI was performed to six type I collagen gel samples with various connection status and a water sample. The evaluation parameters included T1 relaxation time, T2 relaxation time, and diffusion coefficient. With regard to gel samples with cross-links, the T2 relaxation time was shortened in proportion to the dose of glutaraldehyde. It is considered that as the glutaraldehyde concentration increases, the distance between protons in water molecules decreases; this is followed by a stronger bipole-bipole interaction, resulting in a shorter T2 relaxation time. The diffusion coefficient for gel samples with cross-links also decreased with increasing glutaraldehyde concentrations. However, gel samples without glutaraldehyde were almost the same as that of the water. This result suggested that the degree of entrapment of water inside the gel samples without cross-links, even when it converted into gel, was found to be nearly equal to that of the free water

  7. Harnessing emotional connections to improve financial decisions : evaluating the impact of financial education in mainstream media

    OpenAIRE

    Berg,Gunhild; Zia,Bilal Husnain

    2013-01-01

    This paper exploits the emotional connections and viewer attentiveness of mainstream media to evaluate the economic impact of financial education messages on debt management delivered through a popular television soap opera in South Africa. The study uses a symmetric encouragement design to compare outcomes of individuals who were randomly assigned to watch a soap opera with financial mess...

  8. Analytical Study of Common Rigid Steel Connections under the Effect of Heat

    Directory of Open Access Journals (Sweden)

    Rohola Rahnavard

    2014-01-01

    Full Text Available One of the most important members of steel structure’s connection region is beam-to-column connection. Rigid connection in steel moment frame has special role in the behavior of these structures and the fire resistance of these connections can be important. In this paper the behaviors of three common types of rigid connections in Iran under the effect of heat were studied by the use of numerical finite element methods through ABAQUS software. The models were verified by the use of an experimental model through elastic and plastic amplitudes up to collapse and during numerical results, and the effect of large deformation in the nonlinear region has also been considered. The results show that the connection with the end plate had a better performance against heat than other connections. Also reduced stiffness and lateral buckling in this connection were less than other connections.

  9. Online Traffic Condition Evaluation Method for Connected Vehicles Based on Multisource Data Fusion

    Directory of Open Access Journals (Sweden)

    Pang-wei Wang

    2017-01-01

    Full Text Available With the development of connected vehicle (CV and Vehicle to X (V2X communication, more traffic data is being collected from the road network. In order to predict future traffic condition from connected vehicles’ data in real-time, we present an online traffic condition evaluation model utilizing V2X communication. This model employs the Analytic Hierarchy Process (AHP and the multilevel fuzzy set theory to fuse multiple sources of information for prediction. First, the contemporary vehicle data from the On Board Diagnostic (OBD is fused with the static road data in the Road Side Unit (RSU. Then, the real-time traffic evaluation scores are calculated using the variable membership model. The real data collected by OBU in field test demonstrates the feasibility of the evaluation model. Compared with traditional evaluation systems, the proposed model can handle more types of data but demands less data transfer.

  10. Antidepressant Effects of Electroconvulsive Therapy Correlate With Subgenual Anterior Cingulate Activity and Connectivity in Depression

    Science.gov (United States)

    Liu, Yi; Du, Lian; Li, Yongmei; Liu, Haixia; Zhao, Wenjing; Liu, Dan; Zeng, Jinkun; Li, Xingbao; Fu, Yixiao; Qiu, Haitang; Li, Xirong; Qiu, Tian; Hu, Hua; Meng, Huaqing; Luo, Qinghua

    2015-01-01

    Abstract The mechanisms underlying the effects of electroconvulsive therapy (ECT) in major depressive disorder (MDD) are not fully understood. Resting-state functional magnetic resonance imaging (rs-fMRI) is a new tool to study the effects of brain stimulation interventions, particularly ECT. The authors aim to investigate the mechanisms of ECT in MDD by rs-fMRI. They used rs-fMRI to measure functional changes in the brain of first-episode, treatment-naive MDD patients (n = 23) immediately before and then following 8 ECT sessions (brief-pulse square-wave apparatus, bitemporal). They also computed voxel-wise amplitude of low-frequency fluctuation (ALFF) as a measure of regional brain activity and selected the left subgenual anterior cingulate cortex (sgACC) to evaluate functional connectivity between the sgACC and other brain regions. Increased regional brain activity measured by ALFF mainly in the left sgACC following ECT. Functional connectivity of the left sgACC increased in the ipsilateral parahippocampal gyrus, pregenual ACC, contralateral middle temporal pole, and orbitofrontal cortex. Importantly, reduction in depressive symptoms were negatively correlated with increased ALFF in the left sgACC and left hippocampus, and with distant functional connectivity between the left sgACC and contralateral middle temporal pole. That is, across subjects, as depression improved, regional brain activity in sgACC and its functional connectivity increased in the brain. Eight ECT sessions in MDD patients modulated activity in the sgACC and its networks. The antidepressant effects of ECT were negatively correlated with sgACC brain activity and connectivity. These findings suggest that sgACC-associated prefrontal-limbic structures are associated with the therapeutic effects of ECT in MDD. PMID:26559309

  11. Evaluating connection of aquifers to springs and streams, Great Basin National Park and vicinity, Nevada

    Science.gov (United States)

    Prudic, David E.; Sweetkind, Donald S.; Jackson, Tracie R.; Dotson, K. Elaine; Plume, Russell W.; Hatch, Christine E.; Halford, Keith J.

    2015-12-22

    Federal agencies that oversee land management for much of the Snake Range in eastern Nevada, including the management of Great Basin National Park by the National Park Service, need to understand the potential extent of adverse effects to federally managed lands from nearby groundwater development. As a result, this study was developed (1) to attain a better understanding of aquifers controlling groundwater flow on the eastern side of the southern part of the Snake Range and their connection with aquifers in the valleys, (2) to evaluate the relation between surface water and groundwater along the piedmont slopes, (3) to evaluate sources for Big Springs and Rowland Spring, and (4) to assess groundwater flow from southern Spring Valley into northern Hamlin Valley. The study focused on two areas—the first, a northern area along the east side of Great Basin National Park that included Baker, Lehman, and Snake Creeks, and a second southern area that is the potential source area for Big Springs. Data collected specifically for this study included the following: (1) geologic field mapping; (2) drilling, testing, and water quality sampling from 7 test wells; (3) measuring discharge and water chemistry of selected creeks and springs; (4) measuring streambed hydraulic gradients and seepage rates from 18 shallow piezometers installed into the creeks; and (5) monitoring stream temperature along selected reaches to identify places of groundwater inflow.

  12. Evaluation of collagen in connective tissue walls of odontogenic cysts--a histochemical study.

    Science.gov (United States)

    Vij, Ruchieka; Vij, Hitesh; Rao, Nirmala N

    2011-03-01

    The purpose of this study was to evaluate the nature of collagen in the connective tissue walls of odontogenic cysts, like the odontogenic keratocyst (OKC), dentigerous cyst and radicular cyst using picrosirius red stained sections. Furthermore, it was intended to assess if the capsular connective tissue can affect the nature of overlying epithelium, thus emphasizing the role of epithelial-mesenchymal interactions in biological behaviour of the cysts. The material for the study included 51 formalin-fixed paraffin-embedded tissue blocks (15 odontogenic keratocyst, 15 dentigerous cysts, 15 radicular cysts and four normal mucosa and two dental follicular tissue as controls), retrieved from the Department of Oral Pathology and Microbiology, MCODS, Manipal. Tissue blocks were sectioned at 5-μm thickness, stained with picrosirius red stain and observed with polarization and light microscopy. Few sections of OKC and dentigerous cyst exhibited greenish-yellow birefringence in sub-epithelial region, whereas others showed a yellowish-orange birefringence under polarization microscopy. Most radicular cysts had yellowish-orange to orange birefringence. Shift in colour in case OKC and dentigerous cyst was attributed to the presence of inflammation in those sections. These regions also exhibited either a change in phenotype or thickness of overlying epithelium. This technique can be used to study the nature of collagen fibres in odontogenic cyst walls. Further studies with an increased sample size and using various epithelial and mesenchymal markers and ssDNA antibodies should be carried out to confirm the effect of epithelial-mesenchymal interactions on the nature of epithelium of odontogenic cysts. © 2010 John Wiley & Sons A/S.

  13. Experimental Evaluation of the Failure of a Seismic Design Category - B Precast Concrete Beam-Column Connection System

    Science.gov (United States)

    2014-12-01

    Precast Concrete Beam - Column Connection ...ERDC TR-14-12 December 2014 Experimental Evaluation of the Failure of a Seismic Design Category – B Precast Concrete Beam - Column Connection ...systems in order to develop a methodology and obtain basic insight for predicting the brittle failure of precast beam - column connections under

  14. Comparative effectiveness of correction strategies in connected discourse tracking.

    Science.gov (United States)

    Lunato, K E; Weisenberger, J M

    1994-10-01

    The effectiveness of four correction strategies commonly used in connected discourse tracking was investigated in the present study. The strategies were 1) verbatim repetition of a word or phrase; 2) use of antonyms or synonyms as cues; 3) use of phonemic cues, with no whole word repetition; and 4) going back or ahead in the text, with no repetition of the missed segment. Four normal-hearing adults served as listeners. Live-voice presentation of text by two female talkers was employed for all conditions. Listeners were tested in two stimulus presentation modes, speechreading alone and speechreading plus a multichannel tactile aid. Results indicated that strategy 1, repetition of the missed segment, produced the highest tracking rates, significantly higher than any of the other strategies. Strategy 2 produced the lowest tracking rates. Strategies 1 and 3 yielded the lowest percentage of initially missed words, or blockages, and strategy 4 the highest percentage. Significantly higher tracking rates were found under the speechreading plus tactile aid presentation mode, compared with speechreading alone. Further, tracking rates increased significantly from the beginning to the end of training. Data were compared with a more typical CDT task, in which all correction strategies were operative, and results showed little difference in tracking rates between this task and the constrained CDT employing only strategy 1. Overall, results suggest that simple repetition of missed segments is an effective correction strategy for CDT and argue for its inclusion in computer-assisted tracking implementations.

  15. Effect of age on changes in motor units functional connectivity.

    Science.gov (United States)

    Arjunan, Sridhar P; Kumar, Dinesh

    2015-08-01

    With age, there is a change in functional connectivity of motor units in muscle. This leads to reduced muscle strength. This study has investigated the effect of age on the changes in the motor unit recruitment by measuring the mutual information between multiple channels of surface electromyogram (sEMG) of biceps brachii muscle. It is hypothesised that with ageing, there is a reduction in number of motor units, which can lead to an increase in the dependency of remaining motor units. This increase can be observed in the mutual information between the multiple channels of the muscle activity. Two channels of sEMG were recorded during the maximum level of isometric contraction. 28 healthy subjects (Young: age range 20-35years and Old: age range - 60-70years) participated in the experiments. The normalized mutual information (NMI), a measure of dependency factor, was computed for the sEMG recordings. Statistical analysis was performed to test the effect of age on NMI. The results show that the NMI among the older cohort was significantly higher when compared with the young adults.

  16. Evaluation of Green Infrastructure on Peak Flow Mitigation Focusing on the Connectivity of Impervious Areas

    Science.gov (United States)

    Seo, Y.; Hwang, J.; Kwon, Y.

    2017-12-01

    The existence of impervious areas is one of the most distinguishing characteristics of urban catchments. It decreases infiltration and increases direct runoff in urban catchments. The recent introduction of green infrastructure in urban catchments for the purpose of sustainable development contributes to the decrease of the directly connected impervious areas (DCIA) by isolating existing impervious areas and consequently, to the flood risk mitigation. This study coupled the width function-based instantaneous hydrograph (WFIUH), which is able to handle the spatial distribution of the impervious areas, with the concept of the DCIA to assess the impact of decreasing DCIA on the shape of direct runoff hydrographs. Using several scenarios for typical green infrastructure and corresponding changes of DCIA in a test catchment, this study evaluated the effect of green infrastructure on the shape of the resulting direct runoff hydrographs and peak flows. The results showed that the changes in the DCIA immediately affects the shape of the direct runoff hydrograph and decreases peak flows depending on spatial implementation scenarios. The quantitative assessment of the spatial distribution of impervious areas and also the changes to the DCIA suggests effective and well-planned green infrastructure can be introduced in urban environments for flood risk management.

  17. Transuranium elements intake during works connected with the Chernobyl' NPP accident effect elimination

    International Nuclear Information System (INIS)

    Popov, V.I.; Kukhta, B.A.; Kononykhina, N.N.

    1992-01-01

    The materials of studies realized in 1989, 1990, 1991 and dealing with internal irradiation control caused by intake of transuranium elements (TUE) for the Chernobyl' NPP personnel and persons engaged in the accident effect elimination are generalized. the leading part of TUE inhalation intake in formation of internal irradiation doses is revealed. Evaluation of TUE inhalation intake hazards is made according to the results of measuring TUE activity in urine samples for the personnel examined (271 persons). The results of surveillance shows the effect of organism internal irradiation connected with TUE intake through respiratory organs. 23 refs.; 1 tab

  18. Fuzzy comprehensive evaluation for grid-connected performance of integrated distributed PV-ES systems

    Science.gov (United States)

    Lv, Z. H.; Li, Q.; Huang, R. W.; Liu, H. M.; Liu, D.

    2016-08-01

    Based on the discussion about topology structure of integrated distributed photovoltaic (PV) power generation system and energy storage (ES) in single or mixed type, this paper focuses on analyzing grid-connected performance of integrated distributed photovoltaic and energy storage (PV-ES) systems, and proposes a comprehensive evaluation index system. Then a multi-level fuzzy comprehensive evaluation method based on grey correlation degree is proposed, and the calculations for weight matrix and fuzzy matrix are presented step by step. Finally, a distributed integrated PV-ES power generation system connected to a 380 V low voltage distribution network is taken as the example, and some suggestions are made based on the evaluation results.

  19. Variability in connectivity patterns of fish with ontogenetic migrations: Modelling effects of abiotic and biotic factors

    Directory of Open Access Journals (Sweden)

    Susanne Eva Tanner

    2015-10-01

    Full Text Available Connectivity is a critical property of marine fish populations as it drives population replenishment, determines colonization patterns and the resilience of populations to harvest. Understanding connectivity patterns is particularly important in species that present ontogenetic migrations and segregated habitat use during their life history, such as marine species with estuarine nursery areas. Albeit challenging, fish movement can be estimated and quantified using different methodologies depending on the life history stages of interest (e.g. biophysical modelling, otolith chemistry, genetic markers. Relative contributions from estuarine nursery areas to the adult coastal populations were determined using otolith elemental composition and maximum likelihood estimation for four commercially important species (Dicentrarchus labrax, Plathichtys flesus, Solea senegalensis and Solea solea and showed high interannual variability. Here, the effects of abiotic and biotic factors on the observed variability in connectivity rates and extent between estuarine juvenile and coastal adult subpopulations are investigated using generalized linear models (GLM and generalized mixed models (GMM. Abiotic factors impacting both larval and juvenile life history stages are included in the models (e.g. wind force and direction, NAO, water temperature while biotic factors relative to the estuarine residency of juvenile fish are evaluated (e.g. juvenile density, food availability. Factors contributing most to the observed variability in connectivity rates are singled out and compared among species. General trends are identified and results area discussed in the general context of identifying potential management frameworks applicable to different life stages and which may prove useful for ontogenetically migrating species.

  20. Rich-Club Organization in Effective Connectivity among Cortical Neurons.

    Science.gov (United States)

    Nigam, Sunny; Shimono, Masanori; Ito, Shinya; Yeh, Fang-Chin; Timme, Nicholas; Myroshnychenko, Maxym; Lapish, Christopher C; Tosi, Zachary; Hottowy, Pawel; Smith, Wesley C; Masmanidis, Sotiris C; Litke, Alan M; Sporns, Olaf; Beggs, John M

    2016-01-20

    The performance of complex networks, like the brain, depends on how effectively their elements communicate. Despite the importance of communication, it is virtually unknown how information is transferred in local cortical networks, consisting of hundreds of closely spaced neurons. To address this, it is important to record simultaneously from hundreds of neurons at a spacing that matches typical axonal connection distances, and at a temporal resolution that matches synaptic delays. We used a 512-electrode array (60 μm spacing) to record spontaneous activity at 20 kHz from up to 500 neurons simultaneously in slice cultures of mouse somatosensory cortex for 1 h at a time. We applied a previously validated version of transfer entropy to quantify information transfer. Similar to in vivo reports, we found an approximately lognormal distribution of firing rates. Pairwise information transfer strengths also were nearly lognormally distributed, similar to reports of synaptic strengths. Some neurons transferred and received much more information than others, which is consistent with previous predictions. Neurons with the highest outgoing and incoming information transfer were more strongly connected to each other than chance, thus forming a "rich club." We found similar results in networks recorded in vivo from rodent cortex, suggesting the generality of these findings. A rich-club structure has been found previously in large-scale human brain networks and is thought to facilitate communication between cortical regions. The discovery of a small, but information-rich, subset of neurons within cortical regions suggests that this population will play a vital role in communication, learning, and memory. Significance statement: Many studies have focused on communication networks between cortical brain regions. In contrast, very few studies have examined communication networks within a cortical region. This is the first study to combine such a large number of neurons (several

  1. Rich-Club Organization in Effective Connectivity among Cortical Neurons

    Science.gov (United States)

    Shimono, Masanori; Ito, Shinya; Yeh, Fang-Chin; Timme, Nicholas; Myroshnychenko, Maxym; Lapish, Christopher C.; Tosi, Zachary; Hottowy, Pawel; Smith, Wesley C.; Masmanidis, Sotiris C.; Litke, Alan M.; Sporns, Olaf; Beggs, John M.

    2016-01-01

    The performance of complex networks, like the brain, depends on how effectively their elements communicate. Despite the importance of communication, it is virtually unknown how information is transferred in local cortical networks, consisting of hundreds of closely spaced neurons. To address this, it is important to record simultaneously from hundreds of neurons at a spacing that matches typical axonal connection distances, and at a temporal resolution that matches synaptic delays. We used a 512-electrode array (60 μm spacing) to record spontaneous activity at 20 kHz from up to 500 neurons simultaneously in slice cultures of mouse somatosensory cortex for 1 h at a time. We applied a previously validated version of transfer entropy to quantify information transfer. Similar to in vivo reports, we found an approximately lognormal distribution of firing rates. Pairwise information transfer strengths also were nearly lognormally distributed, similar to reports of synaptic strengths. Some neurons transferred and received much more information than others, which is consistent with previous predictions. Neurons with the highest outgoing and incoming information transfer were more strongly connected to each other than chance, thus forming a “rich club.” We found similar results in networks recorded in vivo from rodent cortex, suggesting the generality of these findings. A rich-club structure has been found previously in large-scale human brain networks and is thought to facilitate communication between cortical regions. The discovery of a small, but information-rich, subset of neurons within cortical regions suggests that this population will play a vital role in communication, learning, and memory. SIGNIFICANCE STATEMENT Many studies have focused on communication networks between cortical brain regions. In contrast, very few studies have examined communication networks within a cortical region. This is the first study to combine such a large number of neurons (several

  2. Effects of Cognitive-Behavioral Therapy (CBT) on Brain Connectivity Supporting Catastrophizing in Fibromyalgia.

    Science.gov (United States)

    Lazaridou, Asimina; Kim, Jieun; Cahalan, Christine M; Loggia, Marco L; Franceschelli, Olivia; Berna, Chantal; Schur, Peter; Napadow, Vitaly; Edwards, Robert R

    2017-03-01

    Fibromyalgia (FM) is a chronic, common pain disorder characterized by hyperalgesia. A key mechanism by which cognitive-behavioral therapy (CBT) fosters improvement in pain outcomes is via reductions in hyperalgesia and pain-related catastrophizing, a dysfunctional set of cognitive-emotional processes. However, the neural underpinnings of these CBT effects are unclear. Our aim was to assess CBT's effects on the brain circuitry underlying hyperalgesia in FM patients, and to explore the role of treatment-associated reduction in catastrophizing as a contributor to normalization of pain-relevant brain circuitry and clinical improvement. In total, 16 high-catastrophizing FM patients were enrolled in the study and randomized to 4 weeks of individual treatment with either CBT or a Fibromyalgia Education (control) condition. Resting state functional magnetic resonance imaging scans evaluated functional connectivity between key pain-processing brain regions at baseline and posttreatment. Clinical outcomes were assessed at baseline, posttreatment, and 6-month follow-up. Catastrophizing correlated with increased resting state functional connectivity between S1 and anterior insula. The CBT group showed larger reductions (compared with the education group) in catastrophizing at posttreatment (PCBT produced significant reductions in both pain and catastrophizing at the 6-month follow-up (PCBT group also showed reduced resting state connectivity between S1 and anterior/medial insula at posttreatment; these reductions in resting state connectivity were associated with concurrent treatment-related reductions in catastrophizing. The results add to the growing support for the clinically important associations between S1-insula connectivity, clinical pain, and catastrophizing, and suggest that CBT may, in part via reductions in catastrophizing, help to normalize pain-related brain responses in FM.

  3. Experimental Evaluation of Beam to Diamond Box Column Connection with Through Plate in Moment Frames

    International Nuclear Information System (INIS)

    Keshavarzi, Farhad; Torabian, Shahabeddin; Imanpour, Ali; Mirghaderi, Rasoul

    2008-01-01

    Moment resisting frames with built up section have very enhanced features due to high bending stiffness and strength characteristics in two principal axes and access to column faces for beam to column easy connections. But due to proper transfer of beam stresses to column faces there were always some specific controvertibly issues that how to make the load transfer through and in plane manner in order to mobilize the forces in column faces. Using diamond column instead of box column provide possibility to mobilize the load transfer mechanism in column faces. This section as a column has considerable benefit such as high plastic to elastic section modulus ratio which is an effective factor for force controlled components. Typical connection has no chance to be applied with diamond column.This paper elucidates the seismic behavior of through-plates moment connections to diamond box columns for use in steel moment resisting frames. This connection has a lot of economical benefits such as no need to horizontal continuity plates and satisfying the weak beam--strong column criteria in the connection region. They might serve as panel zone plates as well. According to high shear demand in panel zone of beam to column joint one should use the doublers plates in order to decrease the shear strength demand in this sensitive part of structure but these plates have no possibility to mobilize the load transfer mechanism in column web and transfer them to column flanges. In this type of connection, column faces have effective role in order to decrease the demands on through plate and they are impressive factors for improving the performance of the connection.Experimental analysis was conducted to elucidate the seismic behavior of this connection. The results of Experimental analysis established the effectiveness of the through plate in mitigating local stress concentrations and forming the plastic hinge zone in the beam away from the beam to column interface. The moment

  4. Dynamic Evaluation of LCL-type Grid-Connected Inverters with Different Current Feedback Control Schemes

    DEFF Research Database (Denmark)

    Han, Yang; Li, Zipeng; Guerrero, Josep M.

    2015-01-01

    typical current feedback control schemes in LCL grid-connected system are analyzed and compared systematically. Analysis in s-domain take the effect of the digital computation and modulation delay into account. The stability analysis is presented by root locus in the discrete domain, the optimal values......Proportional-resonant (PR) compensator and LCL filter becomes a better choice in grid-connected inverter system with high performance and low costs. However, the resonance phenomenon caused by LCL filter affect the system stability significantly. In this paper, the stability problem of three...

  5. Reliability/Cost Evaluation on Power System connected with Wind Power for the Reserve Estimation

    DEFF Research Database (Denmark)

    Lee, Go-Eun; Cha, Seung-Tae; Shin, Je-Seok

    2012-01-01

    Wind power is ideally a renewable energy with no fuel cost, but has a risk to reduce reliability of the whole system because of uncertainty of the output. If the reserve of the system is increased, the reliability of the system may be improved. However, the cost would be increased. Therefore...... the reserve needs to be estimated considering the trade-off between reliability and economic aspects. This paper suggests a methodology to estimate the appropriate reserve, when wind power is connected to the power system. As a case study, when wind power is connected to power system of Korea, the effects...

  6. Data uncertainty impact in radiotoxicity evaluation connected to EFR and IRF systems

    International Nuclear Information System (INIS)

    Palmiotti, G.; Salvatores, M.

    1993-01-01

    Time-dependent sensitivity techniques, which have been used in the past for standard reactor applications, have been adapted to calculate the impact of data uncertainties in radiotoxicity evaluations. The methodology has been applied to different strategies of radioactive waste management connected with the EFR and IFR reactor fuel cycles. Results are provided in terms of sensitivity coefficients to basic data (cross sections and decay constants), and uncertainties on global radiotoxicity at different times of storing after discharge

  7. Experimental evaluation of 8 kW grid-connected photovoltaic system in Egypt

    Directory of Open Access Journals (Sweden)

    A. Elkholy

    2016-09-01

    Full Text Available An experimental observation study of 8 kW grid-connected photovoltaic (PV system that is installed at Electronics Research Institute (ERI, Giza, Egypt (Latitude 30.04°N, Longitude 31.21°E, is presented. This study includes the quality of the electrical power generated and injected into the network. The considered system consists of 28 × 295 Wp multicrystalline PV modules, StecaGrid three-phase 8 kW grid-connected inverter and a Solar-Log 300 PM+ for data acquisition and remote monitoring. The power quality parameters at the inverter output side have been measured using CA8335 power quality analyzer. The system has been installed in August 2014 and generated 5.7 MWh till February 2015. The produced electricity by the system is injected directly into the grid without storage device. The purpose of this paper is to present and evaluate the measurements of the power quality parameters obtained from the PV site. Also, this paper presents a comprehensive evaluation of the performance of the system over a period of one week. The observation and analyses exploitation of the collected data can help to evaluate the performance of the PV system connected to the network.

  8. The effect of criticism on functional brain connectivity and associations with neuroticism.

    Directory of Open Access Journals (Sweden)

    Michelle Nadine Servaas

    Full Text Available Neuroticism is a robust personality trait that constitutes a risk factor for psychopathology, especially anxiety disorders and depression. High neurotic individuals tend to be more self-critical and are overly sensitive to criticism by others. Hence, we used a novel resting-state paradigm to investigate the effect of criticism on functional brain connectivity and associations with neuroticism. Forty-eight participants completed the NEO Personality Inventory Revised (NEO-PI-R to assess neuroticism. Next, we recorded resting state functional magnetic resonance imaging (rsfMRI during two sessions. We manipulated the second session before scanning by presenting three standardized critical remarks through headphones, in which the subject was urged to please lie still in the scanner. A seed-based functional connectivity method and subsequent clustering were used to analyse the resting state data. Based on the reviewed literature related to criticism, we selected brain regions associated with self-reflective processing and stress-regulation as regions of interest. The findings showed enhanced functional connectivity between the clustered seed regions and brain areas involved in emotion processing and social cognition during the processing of criticism. Concurrently, functional connectivity was reduced between these clusters and brain structures related to the default mode network and higher-order cognitive control. Furthermore, individuals scoring higher on neuroticism showed altered functional connectivity between the clustered seed regions and brain areas involved in the appraisal, expression and regulation of negative emotions. These results may suggest that the criticized person is attempting to understand the beliefs, perceptions and feelings of the critic in order to facilitate flexible and adaptive social behavior. Furthermore, multiple aspects of emotion processing were found to be affected in individuals scoring higher on neuroticism during

  9. Effects of Large Wood on River-Floodplain Connectivity in a Headwater Appalachian Stream

    Science.gov (United States)

    Keys, T.; Govenor, H.; Jones, C. N.; Hession, W. C.; Scott, D.; Hester, E. T.

    2017-12-01

    Large wood (LW) plays an important, yet often undervalued role in stream ecosystems. Traditionally, LW has been removed from streams for aesthetic, navigational, and flood mitigation purposes. However, extensive research over the last three decades has directly linked LW to critical ecosystem functions including habitat provisioning, stream geomorphic stability, and water quality improvements; and as such, LW has increasingly been implemented in stream restoration activities. One of the proposed benefits to this restoration approach is that LW increases river-floodplain connectivity, potentially decreasing downstream flood peaks and improving water quality. Here, we conducted two experiential floods (i.e., one with and one without LW) in a headwater, agricultural stream to explore the effect of LW on river-floodplain connectivity and resulting hydrodynamic processes. During each flood, we released an equal amount of water to the stream channel, measured stream discharge at upstream and downstream boundaries, and measured inundation depth at multiple locations across the floodplain. We then utilized a 2-dimensional hydrodynamic model (HEC-RAS) to simulate floodplain hydrodynamics. We first calibrated the model using observations from the two experimental floods. Then, we utilized the calibrated model to evaluate differing LW placement strategies and effects under various flow conditions. Results show that the addition of LW to the channel decreased channel velocity and increased inundation extent, inundation depth, and floodplain velocity. Differential placement of LW along the stream impacted the levels of floodplain discharge, primarily due to the geomorphic characteristics of the stream. Finally, we examined the effects of LW on floodplain hydrodynamics across a synthetic flow record, and found that the magnitude of river-floodplain connectivity decreased as recurrence interval increased, with limited impacts on storm events with a recurrence interval of 25 years

  10. Plant functional connectivity – integrating landscape structure and effective dispersal

    NARCIS (Netherlands)

    Auffret, Alistair G.; Rico, Yessica; Bullock, James M.; Hooftman, Danny A.P.; Pakeman, Robin J.; Soons, Merel B.; Suárez-Esteban, Alberto; Traveset, Anna; Wagner, Helene H.; Cousins, Sara A.O.

    2017-01-01

    Dispersal is essential for species to survive the threats of habitat destruction and climate change. Combining descriptions of dispersal ability with those of landscape structure, the concept of functional connectivity has been popular for understanding and predicting species’ spatial responses to

  11. An evaluation of college and low-income youth writing together: self-discovery and cultural connection.

    Science.gov (United States)

    Chandler, Genevieve E

    2002-01-01

    Although the health and healing effects of writing have been documented in the literature, most of the studies have focused primarily on individuals writing alone. This formative evaluation is a component of an intervention reported elsewhere. The evaluation describes the experience of low-income youth and college students (n = 7) writing in a group during a 10-week workshop. The results revealed the development of protective processes of self-esteem, self-efficacy, coping strategies, social support, and cultural connections. In the weekly 2-hr writing sessions, using the Amherst Writers and Artists method, participants were encouraged to write their stories in their own voices in response to prompts, followed by reading aloud and positive feedback. At the end of the 10 weeks participants were interviewed about their experience within the group and outside the group. Analysis of interviews revealed two themes that emerged from the experience of writing together: connection to self through feelings, reflection, and behaviors; and connection to others through learning and empathy. The results suggest that writing in a group using a specific approach facilitated emotional catharsis, increased self knowledge, coping strategies, and understanding and appreciating of others.

  12. The effects of psychosis risk variants on brain connectivity: A Meta-analysis

    Directory of Open Access Journals (Sweden)

    Omar eMothersill

    2012-03-01

    Full Text Available In light of observed changes in connectivity in schizophrenia and the highly heritable nature of the disease, neural connectivity may serve as an important intermediate phenotype for schizophrenia. However, how individual variants confer altered connectivity and which measure of brain connectivity is more proximal to the underlying genetic architecture (i.e. functional or structural has not been well delineated. In this review we consider these issues and the relative sensitivity of imaging methodologies to schizophrenia-related changes in connectivity.We searched PubMed for studies considering schizophrenia risk genes AND functional or structural connectivity. Where data was available, summary statistics were used to determine an estimate of effect size (i.e. Cohen’s d. A random-effects meta-analysis was used to consider (1 the largest effect and (2 all significant effects between functional and structural studies. Schizophrenia risk variants involved in neurotransmission, neurodevelopment and myelin function were found to be associated with altered neural connectivity. On average, schizophrenia risk genes had a large effect on functional (mean d=0.76 and structural connectivity (mean d=1.04. The examination of the largest effect size indicated that the outcomes of functional and structural studies were comparable (Q=2.17, p>0.05. Conversely, consideration of effect size estimates for all significant effects suggest that reported effect sizes in structural connectivity studies were more variable than in functional connectivity studies, and that there was a significant lack of homogeneity across the modalities (Q=6.928, p=0.008.Given the more variable profile of effect sizes associated with structural connectivity, these data may suggest that structural imaging methods are more sensitive to a wider range of effects, as opposed to functional studies which may only be able to determine large effects. These conclusions are limited by

  13. Effects of two teaching methods of connected speech in a Polish EFL classroom

    OpenAIRE

    Kul, Małgorzata

    2017-01-01

    The results demonstrate that in general, NF proved more effective than NNF. With regard to individual processes of connected speech, NF was more effective in production, whereas no such effect was found for perception.

  14. An evaluation of the left-brain vs. right-brain hypothesis with resting state functional connectivity magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Jared A Nielsen

    Full Text Available Lateralized brain regions subserve functions such as language and visuospatial processing. It has been conjectured that individuals may be left-brain dominant or right-brain dominant based on personality and cognitive style, but neuroimaging data has not provided clear evidence whether such phenotypic differences in the strength of left-dominant or right-dominant networks exist. We evaluated whether strongly lateralized connections covaried within the same individuals. Data were analyzed from publicly available resting state scans for 1011 individuals between the ages of 7 and 29. For each subject, functional lateralization was measured for each pair of 7266 regions covering the gray matter at 5-mm resolution as a difference in correlation before and after inverting images across the midsagittal plane. The difference in gray matter density between homotopic coordinates was used as a regressor to reduce the effect of structural asymmetries on functional lateralization. Nine left- and 11 right-lateralized hubs were identified as peaks in the degree map from the graph of significantly lateralized connections. The left-lateralized hubs included regions from the default mode network (medial prefrontal cortex, posterior cingulate cortex, and temporoparietal junction and language regions (e.g., Broca Area and Wernicke Area, whereas the right-lateralized hubs included regions from the attention control network (e.g., lateral intraparietal sulcus, anterior insula, area MT, and frontal eye fields. Left- and right-lateralized hubs formed two separable networks of mutually lateralized regions. Connections involving only left- or only right-lateralized hubs showed positive correlation across subjects, but only for connections sharing a node. Lateralization of brain connections appears to be a local rather than global property of brain networks, and our data are not consistent with a whole-brain phenotype of greater "left-brained" or greater "right

  15. An evaluation of the left-brain vs. right-brain hypothesis with resting state functional connectivity magnetic resonance imaging.

    Science.gov (United States)

    Nielsen, Jared A; Zielinski, Brandon A; Ferguson, Michael A; Lainhart, Janet E; Anderson, Jeffrey S

    2013-01-01

    Lateralized brain regions subserve functions such as language and visuospatial processing. It has been conjectured that individuals may be left-brain dominant or right-brain dominant based on personality and cognitive style, but neuroimaging data has not provided clear evidence whether such phenotypic differences in the strength of left-dominant or right-dominant networks exist. We evaluated whether strongly lateralized connections covaried within the same individuals. Data were analyzed from publicly available resting state scans for 1011 individuals between the ages of 7 and 29. For each subject, functional lateralization was measured for each pair of 7266 regions covering the gray matter at 5-mm resolution as a difference in correlation before and after inverting images across the midsagittal plane. The difference in gray matter density between homotopic coordinates was used as a regressor to reduce the effect of structural asymmetries on functional lateralization. Nine left- and 11 right-lateralized hubs were identified as peaks in the degree map from the graph of significantly lateralized connections. The left-lateralized hubs included regions from the default mode network (medial prefrontal cortex, posterior cingulate cortex, and temporoparietal junction) and language regions (e.g., Broca Area and Wernicke Area), whereas the right-lateralized hubs included regions from the attention control network (e.g., lateral intraparietal sulcus, anterior insula, area MT, and frontal eye fields). Left- and right-lateralized hubs formed two separable networks of mutually lateralized regions. Connections involving only left- or only right-lateralized hubs showed positive correlation across subjects, but only for connections sharing a node. Lateralization of brain connections appears to be a local rather than global property of brain networks, and our data are not consistent with a whole-brain phenotype of greater "left-brained" or greater "right-brained" network strength

  16. Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds.

    Science.gov (United States)

    Amos, Nevil; Harrisson, Katherine A; Radford, James Q; White, Matt; Newell, Graeme; Mac Nally, Ralph; Sunnucks, Paul; Pavlova, Alexandra

    2014-06-01

    Loss of functional connectivity following habitat loss and fragmentation could drive species declines. A comprehensive understanding of fragmentation effects on functional connectivity of an ecological assemblage requires investigation of multiple species with different mobilities, at different spatial scales, for each sex, and in different landscapes. Based on published data on mobility and ecological responses to fragmentation of 10 woodland-dependent birds, and using simulation studies, we predicted that (1) fragmentation would impede dispersal and gene flow of eight "decliners" (species that disappear from suitable patches when landscape-level tree cover falls below species-specific thresholds), but not of two "tolerant" species (whose occurrence in suitable habitat patches is independent of landscape tree cover); and that fragmentation effects would be stronger (2) in the least mobile species, (3) in the more philopatric sex, and (4) in the more fragmented region. We tested these predictions by evaluating spatially explicit isolation-by-landscape-resistance models of gene flow in fragmented landscapes across a 50 x 170 km study area in central Victoria, Australia, using individual and population genetic distances. To account for sex-biased dispersal and potential scale- and configuration-specific effects, we fitted models specific to sex and geographic zones. As predicted, four of the least mobile decliners showed evidence of reduced genetic connectivity. The responses were strongly sex specific, but in opposite directions in the two most sedentary species. Both tolerant species and (unexpectedly) four of the more mobile decliners showed no reduction in gene flow. This is unlikely to be due to time lags because more mobile species develop genetic signatures of fragmentation faster than do less mobile ones. Weaker genetic effects were observed in the geographic zone with more aggregated vegetation, consistent with gene flow being unimpeded by landscape

  17. Evaluation of the Voltage Support Strategies for the Low Voltage Grid Connected PV

    DEFF Research Database (Denmark)

    Demirok, Erhan; Sera, Dezso; Teodorescu, Remus

    2010-01-01

    Admissible range of grid voltage is one of the strictest constraints for the penetration of distributed photovoltaic (PV) generators especially connection to low voltage (LV) public networks. Voltage limits are usually fulfilled either by network reinforcements or limiting of power injections from...... PVs. In order to increase PV penetration level further, new voltage support control functions for individual inverters are required. This paper investigates distributed reactive power regulation and active power curtailment strategies regarding the development of PV connection capacity by evaluation...... of reactive power efforts and requirement of minimum active power curtailment. Furthermore, a small scale experimental setup is built to reflect real grid interaction in the laboratory by achieving critical types of grid (weak and sufficiently stiff)....

  18. Effectiveness of Chain Link Turtle Fence and Culverts in Reducing Turtle Mortality and Providing Connectivity along U.S. Hwy 83, Valentine National Wildlife Refuge, Nebraska, USA

    Science.gov (United States)

    2017-12-01

    We evaluated the effectiveness of existing turtle fences through collecting and analyzing turtle mortality data along U.S. Hwy 83, in and around Valentine National Wildlife Refuge, Nebraska, USA. We also investigated the level of connectivity for tur...

  19. An improved method for evaluating ecological suitability of hydropower development by considering water footprint and transportation connectivity in Tibet, China.

    Science.gov (United States)

    Cui, Guannan; Wang, Xuan; Xu, Linyu; Zhang, Jin; Yu, Bing

    2014-01-01

    Ecological suitability evaluation for hydropower development is effective in locating the most suitable area for construction and emphasizes a clear direction for water resources governance. In this paper, water footprints and transportation connectivity were introduced to improve the existing ecological suitability evaluation application for hydropower development by revising the defects of the traditional indicator system. The following conclusions were reached. (1) Tibet was in a state of water use surplus; the prospect of further hydropower development is positive. (2) Chamdo, Lhasa and Nyingchi excelled in water use efficiency, and Ali was placed last. Nakchu was slightly superior to Ali, but it lagged behind the southern regions. Lhasa, Chamdo, Nyingchi, Xigaze and Shannan were suitable for hydropower development, which could further meet local needs and benefit other regions of China. (3) The evaluation results were in accordance with the actual eco-environmental conditions of the built hydropower projects, indicating that current hydropower development planning was basically reasonable.

  20. Effects of homeostatic constraints on associative memory storage and synaptic connectivity of cortical circuits

    Directory of Open Access Journals (Sweden)

    Julio eChapeton

    2015-06-01

    Full Text Available The impact of learning and long-term memory storage on synaptic connectivity is not completely understood. In this study, we examine the effects of associative learning on synaptic connectivity in adult cortical circuits by hypothesizing that these circuits function in a steady-state, in which the memory capacity of a circuit is maximal and learning must be accompanied by forgetting. Steady-state circuits should be characterized by unique connectivity features. To uncover such features we developed a biologically constrained, exactly solvable model of associative memory storage. The model is applicable to networks of multiple excitatory and inhibitory neuron classes and can account for homeostatic constraints on the number and the overall weight of functional connections received by each neuron. The results show that in spite of a large number of neuron classes, functional connections between potentially connected cells are realized with less than 50% probability if the presynaptic cell is excitatory and generally a much greater probability if it is inhibitory. We also find that constraining the overall weight of presynaptic connections leads to Gaussian connection weight distributions that are truncated at zero. In contrast, constraining the total number of functional presynaptic connections leads to non-Gaussian distributions, in which weak connections are absent. These theoretical predictions are compared with a large dataset of published experimental studies reporting amplitudes of unitary postsynaptic potentials and probabilities of connections between various classes of excitatory and inhibitory neurons in the cerebellum, neocortex, and hippocampus.

  1. Tractography-Based Score for Learning Effective Connectivity From Multimodal Imaging Data Using Dynamic Bayesian Networks.

    Science.gov (United States)

    Dang, Shilpa; Chaudhury, Santanu; Lall, Brejesh; Roy, Prasun K

    2018-05-01

    Effective connectivity (EC) is the methodology for determining functional-integration among the functionally active segregated regions of the brain. By definition EC is "the causal influence exerted by one neuronal group on another" which is constrained by anatomical connectivity (AC) (axonal connections). AC is necessary for EC but does not fully determine it, because synaptic communication occurs dynamically in a context-dependent fashion. Although there is a vast emerging evidence of structure-function relationship using multimodal imaging studies, till date only a few studies have done joint modeling of the two modalities: functional MRI (fMRI) and diffusion tensor imaging (DTI). We aim to propose a unified probabilistic framework that combines information from both sources to learn EC using dynamic Bayesian networks (DBNs). DBNs are probabilistic graphical temporal models that learn EC in an exploratory fashion. Specifically, we propose a novel anatomically informed (AI) score that evaluates fitness of a given connectivity structure to both DTI and fMRI data simultaneously. The AI score is employed in structure learning of DBN given the data. Experiments with synthetic-data demonstrate the face validity of structure learning with our AI score over anatomically uninformed counterpart. Moreover, real-data results are cross-validated by performing classification-experiments. EC inferred on real fMRI-DTI datasets is found to be consistent with previous literature and show promising results in light of the AC present as compared to other classically used techniques such as Granger-causality. Multimodal analyses provide a more reliable basis for differentiating brain under abnormal/diseased conditions than the single modality analysis.

  2. Effects of Field-Map Distortion Correction on Resting State Functional Connectivity MRI

    Directory of Open Access Journals (Sweden)

    Hiroki Togo

    2017-12-01

    Full Text Available Magnetic field inhomogeneities cause geometric distortions of echo planar images used for functional magnetic resonance imaging (fMRI. To reduce this problem, distortion correction (DC with field map is widely used for both task and resting-state fMRI (rs-fMRI. Although DC with field map has been reported to improve the quality of task fMRI, little is known about its effects on rs-fMRI. Here, we tested the influence of field-map DC on rs-fMRI results using two rs-fMRI datasets derived from 40 healthy subjects: one with DC (DC+ and the other without correction (DC−. Independent component analysis followed by the dual regression approach was used for evaluation of resting-state functional connectivity networks (RSN. We also obtained the ratio of low-frequency to high-frequency signal power (0.01–0.1 Hz and above 0.1 Hz, respectively; LFHF ratio to assess the quality of rs-fMRI signals. For comparison of RSN between DC+ and DC− datasets, the default mode network showed more robust functional connectivity in the DC+ dataset than the DC− dataset. Basal ganglia RSN showed some decreases in functional connectivity primarily in white matter, indicating imperfect registration/normalization without DC. Supplementary seed-based and simulation analyses supported the utility of DC. Furthermore, we found a higher LFHF ratio after field map correction in the anterior cingulate cortex, posterior cingulate cortex, ventral striatum, and cerebellum. In conclusion, field map DC improved detection of functional connectivity derived from low-frequency rs-fMRI signals. We encourage researchers to include a DC step in the preprocessing pipeline of rs-fMRI analysis.

  3. Evaluation of Airborne Lidar Elevation Surfaces for Propagation of Coastal Inundation: The Importance of Hydrologic Connectivity

    Directory of Open Access Journals (Sweden)

    Sandra Poppenga

    2015-09-01

    Full Text Available Detailed information about coastal inundation is vital to understanding dynamic and populated areas that are impacted by storm surge and flooding. To understand these natural hazard risks, lidar elevation surfaces are frequently used to model inundation in coastal areas. A single-value surface method is sometimes used to inundate areas in lidar elevation surfaces that are below a specified elevation value. However, such an approach does not take into consideration hydrologic connectivity between elevation grids cells resulting in inland areas that should be hydrologically connected to the ocean, but are not. Because inland areas that should drain to the ocean are hydrologically disconnected by raised features in a lidar elevation surface, simply raising the water level to propagate coastal inundation will lead to inundation uncertainties. We took advantage of this problem to identify hydrologically disconnected inland areas to point out that they should be considered for coastal inundation, and that a lidar-based hydrologic surface should be developed with hydrologic connectivity prior to inundation analysis. The process of achieving hydrologic connectivity with hydrologic-enforcement is not new, however, the application of hydrologically-enforced lidar elevation surfaces for improved coastal inundation mapping as approached in this research is innovative. In this article, we propagated a high-resolution lidar elevation surface in coastal Staten Island, New York to demonstrate that inland areas lacking hydrologic connectivity to the ocean could potentially be included in inundation delineations. For inland areas that were hydrologically disconnected, we evaluated if drainage to the ocean was evident, and calculated an area exceeding 11 ha (~0.11 km2 that could be considered in inundation delineations. We also assessed land cover for each inland area to determine the type of physical surfaces that would be potentially impacted if the inland areas

  4. Evaluation of airborne lidar elevation surfaces for propagation of coastal inundation: the importance of hydrologic connectivity

    Science.gov (United States)

    Poppenga, Sandra K.; Worstell, Bruce B.

    2015-01-01

    Detailed information about coastal inundation is vital to understanding dynamic and populated areas that are impacted by storm surge and flooding. To understand these natural hazard risks, lidar elevation surfaces are frequently used to model inundation in coastal areas. A single-value surface method is sometimes used to inundate areas in lidar elevation surfaces that are below a specified elevation value. However, such an approach does not take into consideration hydrologic connectivity between elevation grids cells resulting in inland areas that should be hydrologically connected to the ocean, but are not. Because inland areas that should drain to the ocean are hydrologically disconnected by raised features in a lidar elevation surface, simply raising the water level to propagate coastal inundation will lead to inundation uncertainties. We took advantage of this problem to identify hydrologically disconnected inland areas to point out that they should be considered for coastal inundation, and that a lidar-based hydrologic surface should be developed with hydrologic connectivity prior to inundation analysis. The process of achieving hydrologic connectivity with hydrologic-enforcement is not new, however, the application of hydrologically-enforced lidar elevation surfaces for improved coastal inundation mapping as approached in this research is innovative. In this article, we propagated a high-resolution lidar elevation surface in coastal Staten Island, New York to demonstrate that inland areas lacking hydrologic connectivity to the ocean could potentially be included in inundation delineations. For inland areas that were hydrologically disconnected, we evaluated if drainage to the ocean was evident, and calculated an area exceeding 11 ha (~0.11 km2) that could be considered in inundation delineations. We also assessed land cover for each inland area to determine the type of physical surfaces that would be potentially impacted if the inland areas were considered as

  5. The importance of probabilistic evaluations in connection with risk analyses according to technical safety laws

    International Nuclear Information System (INIS)

    Mathiak, E.

    1984-01-01

    The nuclear energy sector exemplifies the essential importance to be attached to the practical application of probabilistic evaluations (e.g. probabilistic reliability analyses) in connection with the legal risk assessment of technical systems and installations. The study is making use of a triad risk analysis and tries to reconcile the natural science and legal points of view. Without changing the definitions of 'risk' and 'hazard' in the legal sense of their meaning the publication discusses their reconcilation with the laws of natural science, their interpretation and application in view of the latter. (HSCH) [de

  6. Experimental Behavior Evaluation of Series and Parallel Connected Constant Phase Elements

    KAUST Repository

    Tsirimokou, Georgia

    2017-01-28

    Fractional-order capacitors are the core building blocks for implementing fractional-order circuits. Due to the absence of their commercial availability, they can be approximated through appropriately configured passive or active integer-order element topologies. Such a topology, constructed using Operational Transconductance Amplifiers (OTAs) and capacitors has been implemented in monolithic form through the AMS 0.35μm CMOS process, and the fabricated chips are employed here for the experimental evaluation of the behavior of networks constructed from fractional-order capacitors connected in series or in parallel.

  7. Data uncertainty impact in radiotoxicity evaluation connected to EFR and IFR systems

    International Nuclear Information System (INIS)

    Palmiotti, G.; Salvatores, M.

    1993-01-01

    Time-dependent sensitivity techniques, which have been used in the past for standard reactor applications, have been adapted to calculate the impact of data uncertainties in radiotoxicity evaluations. The methodology has been applied to different strategies of radioactive waste management connected with the EFR and IFR reactor fuel cycles. Results are provided in terms of sensitivity coefficients to basic data (cross sections and decay constants), and uncertainties on global radiotoxicity at different times of storing after discharge. 6 refs., 6 figs., 9 tabs

  8. Pore connectivity effects on solute transport in rocks

    International Nuclear Information System (INIS)

    Hu, Qinhong; Ewing, Robert P.

    2001-01-01

    Retardation of nuclear contaminants in rock matrices can lead to long retention times, allowing substantial radionuclide decay prior to eventual release. Imbibition and diffusion into the rock matrix can move contaminants away from an active fracture, thereby contributing to their retardation. However, diffusive transport in some rocks may behave anomalously because of their sparsely connected porespace, in contrast to diffusion in rocks with denser pore connections. We examined imbibition of weakly sorbing tracers into welded tuff and Indiana sandstone, and water imbibition into metagraywacke and Berea sandstone. Tuff samples were initially equilibrated to 12% and 76% water (v/v) within controlled humidity chambers, while the other rocks were air-dried. For imbibition, one face was exposed to water, with or without tracer, and uptake was measured over time. Following imbibition, tracer concentration measurements were made at fine (1 mm) increments. Three anomalous results were observed: (1) Indiana sandstone and metagraywacke showed mass of imbibed water scaling as time 0.26 , while tuff and Berea sandstone showed the more classical scaling with time 0.5 ; (2) tracer movement into dry (2% initial saturation) Indiana sandstone showed a dispersion pattern similar to that expected during tracer movement into moist (76% initial saturation) tuff; and (3) tracer concentrations at the inlet face of the tuff sample were approximately twice those deeper inside the sample. The experiment was then modeled using random walk methods on a 3-D lattice with different values of pore coordination. Network model simulations that used a pore coordination of 1.49 for Indiana sandstone and 1.56 for metagraywacke showed similar temporal scaling, a result of their porespace being close to the percolation threshold. Tracer concentration profiles in Indiana sandstone and tuff were closely matched by simulations that used pore coordinations of 1.49 and 1.68, respectively, because of how low

  9. Pore Connectivity Effects on Solute Transport in Rocks

    International Nuclear Information System (INIS)

    Oinhong Hu

    2001-01-01

    Retardation of nuclear contaminants in rock matrices can lead to long retention times, allowing substantial radionuclide decay prior to eventual release. Imbibition and diffusion into the rock matrix can move contaminants away from an active fracture, thereby contributing to their retardation. However, diffusive transport in some rocks may behave anomalously because of their sparsely connected porespace, in contrast to diffusion in rocks with denser pore connections. We examined imbibition of weakly sorbing tracers into welded tuff and Indiana sandstone, and water imbibition into metagraywacke and Berea sandstone. Tuff samples were initially equilibrated to 12% and 76% water (v/v) within controlled humidity chambers, while the other rocks were air-dried. For imbibition, one face was exposed to water, with or without tracer, and uptake was measured over time. Following imbibition, tracer concentration measurements were made at fine (1 mm) increments. Three anomalous results were observed: (1) Indiana sandstone and metagraywacke showed mass of imbibed water scaling as time 0.26 , while tuff and Berea sandstone showed the more classical scaling with time 0.05 ; (2) tracer movement into dry (2% initial saturation) Indiana sandstone showed a dispersion pattern similar to that expected during tracer movement into moist (76% initial saturation) tuft and (3) tracer concentrations at the inlet face of the tuff sample were approximately twice those deeper inside the sample. The experiment was then modeled using random walk methods on a 3-D lattice with different values of pore coordination. Network model simulations that used a pore coordination of 1.49 for Indiana sandstone and 1.56 for metagraywacke showed similar temporal scaling, a result of their porespace being close to the percolation threshold. Tracer concentration profiles in Indiana sandstone and tuff were closely matched by simulations that used pore coordinations of 1.49 and 1.68, respectively, because of how low

  10. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Directory of Open Access Journals (Sweden)

    Christine Beauchene

    Full Text Available Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  11. The Effect of Binaural Beats on Visuospatial Working Memory and Cortical Connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2016-01-01

    Binaural beats utilize a phenomenon that occurs within the cortex when two different frequencies are presented separately to each ear. This procedure produces a third phantom binaural beat, whose frequency is equal to the difference of the two presented tones and which can be manipulated for non-invasive brain stimulation. The effects of binaural beats on working memory, the system in control of temporary retention and online organization of thoughts for successful goal directed behavior, have not been well studied. Furthermore, no studies have evaluated the effects of binaural beats on brain connectivity during working memory tasks. In this study, we determined the effects of different acoustic stimulation conditions on participant response accuracy and cortical network topology, as measured by EEG recordings, during a visuospatial working memory task. Three acoustic stimulation control conditions and three binaural beat stimulation conditions were used: None, Pure Tone, Classical Music, 5Hz binaural beats, 10Hz binaural beats, and 15Hz binaural beats. We found that listening to 15Hz binaural beats during a visuospatial working memory task not only increased the response accuracy, but also modified the strengths of the cortical networks during the task. The three auditory control conditions and the 5Hz and 10Hz binaural beats all decreased accuracy. Based on graphical network analyses, the cortical activity during 15Hz binaural beats produced networks characteristic of high information transfer with consistent connection strengths throughout the visuospatial working memory task.

  12. Evaluation of tube to collector connection by hydraulic expansion method in PGV-1000 steam generators

    International Nuclear Information System (INIS)

    Dashti, H.G.; Hashemi, B.; Jahromi, S.A.

    2011-01-01

    Research highlights: → The produced residual stresses in the collector body due to hydraulic expansion method have been compared with explosive method. → The residual stresses were obtained using two methods of FEM and strain gauging tests. → The effect of clearance between tube and collector on the residual stresses was investigated. → The contact stresses between the tube and collector interface were modeled and the required connection strength between tube and collector is estimated based on ASME rules and compared with FE results. - Abstract: Investigations on steam generators failure due to cracking in collector ligaments at perforated parts determined that connection process of the tubes to collector could be one of the main breakdown causes. The stability and strength of tube to collector joint is dependent to the geometry of tube and collector, the joining process and the operational conditions. In this research hydraulic expansion method has been considered as connection method of tube to collector. The Finite Element Method (FEM) was used to simulate the hydraulic expansion process and determine stress condition of the joints. The contact stresses between the tube and collector interface were modeled using contact elements of ANSYS program. Furthermore, the effect of clearance between tube and collector on the residual stresses around of joints was investigated. Some specimens from collector and tube materials were tested at various temperatures and their results were used at rate-independent multi-linear Mises plasticity model for FE analysis. Required connection strength between tube and collector is estimated based on ASME rules and compared with FE results. The results show that the residual tensile stresses could be greatly increased by decreasing of initial clearance. The highest value of residual stresses was observed around of collector holes nevertheless it was considerably lesser than obtained residual stresses in explosive method. The

  13. Evaluation of structural deformations of a mechanical connecting unit oxidizer supplies by thermo-mechanical simulation

    International Nuclear Information System (INIS)

    Kim, Sang Woo

    2016-01-01

    A Mechanical connecting unit (MCU) used in ground facilities for a Liquid propellant rocket (LPR) acts as a bridge between the onboard system and the ground oxidizer filling system. It should be resistant to structural deformations in order to guarantee successful supply of a cryogenic oxidizer and high pressure gases without reduction of sealing capability. The MCU consists of many components and linkages and operates under harsh conditions induced by a cryogenic oxidizer, high pressure gases and other mechanical forces. Thus, the evaluation of structural deformation of the MCU considering complex conditions is expensive and time consuming. The present study efficiently evaluates the structural deformations of the key components of the MCU by Thermo-mechanical simulation (TMS) based on the superposition principle. Deformations due to the mechanical loadings including weights, pressures, and spring forces are firstly evaluated by using a non-linear flexible body simulation module (FFlex) of Multi-body dynamics (MBD) software, RecurDyn. Then, thermal deformations for the deformed geometries obtained by RecurDyn were subsequently calculated. It was conducted by using a Finite element (FE) analysis software, ANSYS. The total deformations for the onboard plate and multi-channel plate in the connecting section due to the mechanical and thermal loadings were successfully evaluated. Moreover, the outer gaps at six points between two plates were calculated and verified by comparison to the measured data. Their values and tendencies showed a good agreement. The author concluded that the TMS using MBD software considering flexible bodies and an FE simulator can efficiently evaluate structural deformations of the MCU operating under the complex load and boundary conditions

  14. Evaluation of structural deformations of a mechanical connecting unit oxidizer supplies by thermo-mechanical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Woo [Dept. of Mechanical Engineering, Institute of Machine Convergence Technology, Hankyong National University, Anseong (Korea, Republic of)

    2016-10-15

    A Mechanical connecting unit (MCU) used in ground facilities for a Liquid propellant rocket (LPR) acts as a bridge between the onboard system and the ground oxidizer filling system. It should be resistant to structural deformations in order to guarantee successful supply of a cryogenic oxidizer and high pressure gases without reduction of sealing capability. The MCU consists of many components and linkages and operates under harsh conditions induced by a cryogenic oxidizer, high pressure gases and other mechanical forces. Thus, the evaluation of structural deformation of the MCU considering complex conditions is expensive and time consuming. The present study efficiently evaluates the structural deformations of the key components of the MCU by Thermo-mechanical simulation (TMS) based on the superposition principle. Deformations due to the mechanical loadings including weights, pressures, and spring forces are firstly evaluated by using a non-linear flexible body simulation module (FFlex) of Multi-body dynamics (MBD) software, RecurDyn. Then, thermal deformations for the deformed geometries obtained by RecurDyn were subsequently calculated. It was conducted by using a Finite element (FE) analysis software, ANSYS. The total deformations for the onboard plate and multi-channel plate in the connecting section due to the mechanical and thermal loadings were successfully evaluated. Moreover, the outer gaps at six points between two plates were calculated and verified by comparison to the measured data. Their values and tendencies showed a good agreement. The author concluded that the TMS using MBD software considering flexible bodies and an FE simulator can efficiently evaluate structural deformations of the MCU operating under the complex load and boundary conditions.

  15. Fish with Chips: Tracking Reef Fish Movements to Evaluate Size and Connectivity of Caribbean Marine Protected Areas

    Science.gov (United States)

    Pittman, Simon J.; Monaco, Mark E.; Friedlander, Alan M.; Legare, Bryan; Nemeth, Richard S.; Kendall, Matthew S.; Poti, Matthew; Clark, Randall D.; Wedding, Lisa M.; Caldow, Chris

    2014-01-01

    Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40–64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness. PMID:24797815

  16. Fish with chips: tracking reef fish movements to evaluate size and connectivity of Caribbean marine protected areas.

    Directory of Open Access Journals (Sweden)

    Simon J Pittman

    Full Text Available Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40-64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.

  17. The effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria

    Science.gov (United States)

    Zaghba, L.; Khennane, M.; Terki, N.; Borni, A.; Bouchakour, A.; Fezzani, A.; Mahamed, I. Hadj; Oudjana, S. H.

    2017-02-01

    This paper presents modeling, simulation, and analysis evaluation of the grid-connected PV generation system performance under MATLAB/Simulink. The objective is to study the effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria. This system works with a power converter. This converter allows the connection to the network and extracts maximum power from photovoltaic panels with the MPPT algorithm based on robust neuro-fuzzy sliding approach. The photovoltaic energy produced by the PV generator will be completely injected on the network. Simulation results show that the system controlled by the neuro-fuzzy sliding adapts to changing external disturbances and show their effectiveness not only for continued maximum power point but also for response time and stability.

  18. An economic evaluation of photovoltaic grid connected systems (PVGCS) in Flanders for companies: A generic model

    International Nuclear Information System (INIS)

    Audenaert, Amaryllis; De Boeck, Liesje; De Cleyn, Sven; Lizin, Sebastien; Adam, Jean-Francois

    2010-01-01

    In this paper an economic evaluation of photovoltaic grid connected systems (PVGCS) for companies situated in Flanders (Belgium) is conducted by using a generic Excel model. The model is unique in that it includes the dimension of taxation. This inclusion is required, otherwise the fiscal benefit of using solar panels is not accounted for. The model uses the cash flow projection method. This technique allows the calculation of the following classical evaluation criteria: net present value, internal rate of return, payback period, discounted payback period, profitability index, yield unit cost, yield unit revenue and break-even turnkey cost. Their outcome makes it possible to answer the question whether installing a PVGCS in Flanders is a responsible financial investment for companies. Furthermore, the paper estimates whether the corporate environment is ready for a subsidy legislation change. This change has recently been announced and as such it is possible to gauge whether the current market situation is profitable given future legislation. (author)

  19. Biomechanical evaluation of different abutment-implant connections - A nonlinear finite element analysis

    Science.gov (United States)

    Ishak, Muhammad Ikman; Shafi, Aisyah Ahmad; Rosli, M. U.; Khor, C. Y.; Zakaria, M. S.; Rahim, Wan Mohd Faizal Wan Abd; Jamalludin, Mohd Riduan

    2017-09-01

    The success of dental implant surgery is majorly dependent on the stability of prosthesis to anchor to implant body as well as the integration of implant body to bone. The attachment between dental implant body and abutment plays a vital role in attributing to the stability of dental implant system. A good connection between implant body cavity to abutment may minimize the complications of abutment loosening and implant fractures as widely reported in clinical findings. The aim of this paper is to investigate the effect of different abutment-implant connections on stress dispersion within the abutment and implant bodies as well as displacement of implant body via three-dimensional (3-D) finite element analysis (FEA). A 3-D model of mandible was reconstructed from computed tomography (CT) image datasets using an image-processing software with the selected region of interest was the left side covering the second premolar, first molar and second molar regions. The bone was modelled as compact (cortical) and porous (cancellous) structures. Besides, three implant bodies and three generic models of abutment with different types of connections - tapered interference fit (TIF), tapered integrated screwed-in (TIS) and screw retention (SR) were created using computer-aided design (CAD) software and all models were then analysed via 3D FEA software. Occlusal forces of 114.6 N, 17.2 N and 23.4 N were applied in the axial, lingual and mesio-distal directions, respectively, on the top surface of first molar crown. All planes of the mandibular bone model were rigidly fixed. The result exhibited that abutment with TIS connection produced the most favourable stress and displacement outcomes as compared to other attachment types. This is due to the existence of integrated screw at the bottom portion of tapered abutment which increases the motion resistance.

  20. Functional and effective whole brain connectivity using magnetoencephalography to identify monozygotic twin pairs

    NARCIS (Netherlands)

    Demuru, M.; Gouw, A.; Hillebrand, A.; Stam, C J; van Dijk, B W; Scheltens, P.; Tijms, B.M.; Konijnenberg, E.; ten Kate-Booij, M.J.; den Braber, A; Smit, D J A; Boomsma, D I; Visser, P J

    2017-01-01

    Resting-state functional connectivity patterns are highly stable over time within subjects. This suggests that such 'functional fingerprints' may have strong genetic component. We investigated whether the functional (FC) or effective (EC) connectivity patterns of one monozygotic twin could be used

  1. No functionally relevant mechanical effects of epimuscular myofascial connections between rat ankle plantar flexors

    NARCIS (Netherlands)

    Tijs, C.; van Dieen, J.H.; Maas, H.

    2015-01-01

    Triceps surae muscles are mechanically connected by the shared Achilles tendon and by epimuscular myofascial connections. We aimed to assess the effects of proximal lengthening of gastrocnemius and plantaris muscles, imposed by changes in knee angle, on the magnitude and direction of the 3D ankle

  2. Functional localization and effective connectivity of cortical theta and alpha oscillatory activity during an attention task

    Directory of Open Access Journals (Sweden)

    Yuichi Kitaura

    Full Text Available Objectives: The aim of this paper is to investigate cortical electric neuronal activity as an indicator of brain function, in a mental arithmetic task that requires sustained attention, as compared to the resting state condition. The two questions of interest are the cortical localization of different oscillatory activities, and the directional effective flow of oscillatory activity between regions of interest, in the task condition compared to resting state. In particular, theta and alpha activity are of interest here, due to their important role in attention processing. Methods: We adapted mental arithmetic as an attention ask in this study. Eyes closed 61-channel EEG was recorded in 14 participants during resting and in a mental arithmetic task (“serial sevens subtraction”. Functional localization and connectivity analyses were based on cortical signals of electric neuronal activity estimated with sLORETA (standardized low resolution electromagnetic tomography. Functional localization was based on the comparison of the cortical distributions of the generators of oscillatory activity between task and resting conditions. Assessment of effective connectivity was based on the iCoh (isolated effective coherence method, which provides an appropriate frequency decomposition of the directional flow of oscillatory activity between brain regions. Nine regions of interest comprising nodes from the dorsal and ventral attention networks were selected for the connectivity analysis. Results: Cortical spectral density distribution comparing task minus rest showed significant activity increase in medial prefrontal areas and decreased activity in left parietal lobe for the theta band, and decreased activity in parietal-occipital regions for the alpha1 band. At a global level, connections among right hemispheric nodes were predominantly decreased during the task condition, while connections among left hemispheric nodes were predominantly increased. At more

  3. Connections rigidity effect on probability of fracture in steel moment frames

    Directory of Open Access Journals (Sweden)

    Gholamreza Abdollahzadeh

    2017-08-01

    Full Text Available Connections in steel moment frames are idealized in full pinned and full rigid conditions. Because with this assumption, in spite of real behavior of connection, real story drifts are less anticipated and maybe frame is designed without performance of bracing. There are several methods for modeling actual behavior of semi rigid connections. In this method a connection with certain rigidity is modeled by a rotational spring with corresponding stiffness. This stiffness is achieved by certain formula. In other words, each percent of rigidity corresponds to one rotational spring stiffness. In this research in order to evaluate the real behavior of connection in analysis and designing process and fracture probability one frame including four stories and one bay with three types of connection has been modeled and designed in ETABS. Each model has an individual rigidity which is equal to 10, 75 and 90 percent. With respect to maximum drift and different PGA in roof, probabilities of low, medium, high and complete fracture were calculated. For this purpose, with applying different PGA to modeled frames, amounts of drift in the roof are achieved. Then these values are compared with given values in American code. Finally, investigation showed that when rigidity in frame connections increases, the probability of frame fracture decreases. In other words, fully rigid assumption of connection in analysis process leads to decreasing in real probability of fracture in frames which is a noticeable risk in building designing processes.

  4. Evaluation of Harmonic Content from a Tap Transformer Based Grid Connection System for Wind Power

    Directory of Open Access Journals (Sweden)

    S. Apelfröjd

    2013-01-01

    Full Text Available Simulations done in MATLAB/Simulink together with experiments conducted at the Ångströms laboratory are used to evaluate and discuss the total harmonic distortion (THD and total demand distortion (TDD of a tap transformer based grid connection system. The grid connection topology can be used with different turbine and generator topologies and is here applied on a vertical axis wind turbine (VAWT with a permanent magnet synchronous generator (PMSG and its operational scheme. The full variable-speed wind conversion system consists of a diode rectifier, DC link, IGBT inverter, LCL-filter, and tap transformer. The full variable-speed operation is enabled by the use of the different step-up ratios of the tap transformer. In the laboratory study, a full experimental setup of the system was used, a clone of the on-site PMSG driven by a motor was used, and the grid was replaced with a resistive load. With a resistive load, grid harmonics and possible unbalances are removed. The results show a TDD and THD below 5% for the full operating range and harmonic values within the limits set up by IEEE-519. Furthermore, a change in tap, going to a lower step-up ratio, results in a reduction in both THD and TDD for the same output power.

  5. Evaluation of an automated connective tissue disease screening assay in Korean patients with systemic rheumatic diseases.

    Directory of Open Access Journals (Sweden)

    Seri Jeong

    Full Text Available This study aimed to evaluate the diagnostic utilities of the automated connective tissues disease screening assay, CTD screen, in patients with systemic rheumatic diseases. A total of 1093 serum samples were assayed using CTD screen and indirect immunofluorescent (IIF methods. Among them, 162 were diagnosed with systemic rheumatic disease, including rheumatoid arthritis (RA, systemic lupus erythematosus (SLE, and mixed connective tissue disease (MCT. The remaining 931 with non-systemic rheumatic disease were assigned to the control group. The median ratios of CTD screen tests were significantly higher in the systemic rheumatic disease group than in the control group. The positive likelihood ratios of the CTD screen were higher than those of IIF in patients with total rheumatic diseases (4.1 vs. 1.6, including SLE (24.3 vs. 10.7. The areas under the receiver operating characteristic curves (ROC-AUCs of the CTD screen for discriminating total rheumatic diseases, RA, SLE, and MCT from controls were 0.68, 0.56, 0.92 and 0.80, respectively. The ROC-AUCs of the combinations with IIF were significantly higher in patients with total rheumatic diseases (0.72 and MCT (0.85 than in those of the CTD screen alone. Multivariate analysis indicated that both the CTD screen and IIF were independent variables for predicting systemic rheumatic disease. CTD screen alone and in combination with IIF were a valuable diagnostic tool for predicting systemic rheumatic diseases, particularly for SLE.

  6. Evaluation of an automated connective tissue disease screening assay in Korean patients with systemic rheumatic diseases.

    Science.gov (United States)

    Jeong, Seri; Yang, Heeyoung; Hwang, Hyunyong

    2017-01-01

    This study aimed to evaluate the diagnostic utilities of the automated connective tissues disease screening assay, CTD screen, in patients with systemic rheumatic diseases. A total of 1093 serum samples were assayed using CTD screen and indirect immunofluorescent (IIF) methods. Among them, 162 were diagnosed with systemic rheumatic disease, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and mixed connective tissue disease (MCT). The remaining 931 with non-systemic rheumatic disease were assigned to the control group. The median ratios of CTD screen tests were significantly higher in the systemic rheumatic disease group than in the control group. The positive likelihood ratios of the CTD screen were higher than those of IIF in patients with total rheumatic diseases (4.1 vs. 1.6), including SLE (24.3 vs. 10.7). The areas under the receiver operating characteristic curves (ROC-AUCs) of the CTD screen for discriminating total rheumatic diseases, RA, SLE, and MCT from controls were 0.68, 0.56, 0.92 and 0.80, respectively. The ROC-AUCs of the combinations with IIF were significantly higher in patients with total rheumatic diseases (0.72) and MCT (0.85) than in those of the CTD screen alone. Multivariate analysis indicated that both the CTD screen and IIF were independent variables for predicting systemic rheumatic disease. CTD screen alone and in combination with IIF were a valuable diagnostic tool for predicting systemic rheumatic diseases, particularly for SLE.

  7. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    International Nuclear Information System (INIS)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-01-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results

  8. Evaluation of muscular lesions in connective tissue diseases: thallium 201 muscular scans

    Energy Technology Data Exchange (ETDEWEB)

    Guillet, G.; Guillet, J.; Sanciaume, C.; Maleville, J.; Geniaux, M.; Morin, P.

    1988-04-01

    We performed thallium 201 muscle scans to assess muscular involvement in 40 patients with different connective tissue diseases (7 with dermatomyositis, 7 with systemic lupus erythematosus, 12 with progressive systemic scleroderma, 2 with calcinosis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia (CREST) syndrome, 3 with monomelic scleroderma, 6 with morphea, and 3 with Raynaud's disease). Only 12 of these patients complained of fatigability and/or myalgia. Electromyography was performed and serum levels of muscle enzymes were measured in all patients. Comparison of thallium 201 exercise recording with the other tests revealed that scan sensitivity is greater than electromyographic and serum muscle enzymes levels. Thallium 201 scans showed abnormal findings in 32 patients and revealed subclinical lesions in 18 patients, while electromyography findings were abnormal in 25 of these 32 patients. Serum enzyme levels were raised in only 8 patients. Thallium 201 scanning proved to be a useful guide for modifying therapy when laboratory data were conflicting. It was useful to evaluate treatment efficacy. Because our data indicate a 100% positive predictive value, we believe that thallium 201 scanning should be advised for severe systemic connective tissue diseases with discordant test results.

  9. Some important questions connected with non-targeted effects

    International Nuclear Information System (INIS)

    Baverstock, Keith; Belyakov, Oleg V.

    2010-01-01

    This paper briefly reviews the highlights of experimental evidence that led to the adoption of the term 'non-targeted' to describe new effects induced by ionising radiation that did not fit the classical radiobiological paradigm, principally genomic instability and bystander effect, identifying the reports that were most influential on the subsequent course of radiobiological research. The issue of appropriate terminology for the new effects is discussed. Particular emphasis is placed on the inheritance of genomic instability, where there are issues concerning which effects should be considered as transgenerational. Finally, in respect of the question as to whether these new effects are likely to have an impact on human health is addressed. It is concluded that there is a need for a clearer terminology to facilitate research progress, that real health effects cannot be ruled out and that therefore there is a need for new paradigms not only for radiobiology but also for risk assessment and radiological protection.

  10. Advice taking from humans and machines: an fMRI and effective connectivity study

    Directory of Open Access Journals (Sweden)

    Kimberly Goodyear

    2016-11-01

    Full Text Available With new technological advances, advice can come from different sources such as machines or humans, but how individuals respond to such advice and the neural correlates involved need to be better understood. We combined functional MRI and multivariate Granger causality analysis with an X-ray luggage-screening task to investigate the neural basis and corresponding effective connectivity involved with advice utilization from agents framed as experts. Participants were asked to accept or reject good or bad advice from a human or machine agent with low reliability (high false alarm rate. We showed that unreliable advice decreased performance overall and participants interacting with the human agent had a greater depreciation of advice utilization during bad advice compared to the machine agent. These differences in advice utilization can be perceivably due to reevaluation of expectations arising from association of dispositional credibility for each agent. We demonstrated that differences in advice utilization engaged brain regions that may be associated with evaluation of personal characteristics and traits (precuneus, posterior cingulate cortex, temporoparietal junction and interoception (posterior insula. We found that the right posterior insula and left precuneus were the drivers of the advice utilization network that were reciprocally connected to each other and also projected to all other regions. Our behavioral and neuroimaging results have significant implications for society because of progressions in technology and increased interactions with machines.

  11. Analysis and Relative Evaluation of Connectivity of a Mobile Multi-Hop Network

    Science.gov (United States)

    Nakano, Keisuke; Miyakita, Kazuyuki; Sengoku, Masakazu; Shinoda, Shoji

    In mobile multi-hop networks, a source node S and a destination node D sometimes encounter a situation where there is no multi-hop path between them when a message M, destined for D, arrives at S. In this situation, we cannot send M from S to D immediately; however, we can deliver M to D after waiting some time with the help of two capabilities of mobility. One of the capabilities is to construct a connected multi-hop path by changing the topology of the network during the waiting time (Capability 1), and the other is to move M closer to D during the waiting time (Capability 2). In this paper, we consider three methods to deliver M from S to D by using these capabilities in different ways. Method 1 uses Capability 1 and sends M from S to D after waiting until a connected multi-hop path appears between S and D. Method 2 uses Capability 2 and delivers M to D by allowing a mobile node to carry M from S to D. Method 3 is a combination of Methods 1 and 2 and minimizes the waiting time. We evaluate and compare these three methods in terms of the mean waiting time, from the time when M arrives at S to the time when D starts receiving M, as a new approach to connectivity evaluation. We consider a one-dimensional mobile multi-hop network consisting of mobile nodes flowing in opposite directions along a street. First, we derive some approximate equations and propose an estimation method to compute the mean waiting time of Method 1. Second, we theoretically analyze the mean waiting time of Method 2, and compute a lower bound of that of Method 3. By comparing the three methods under the same assumptions using results of the analyses and some simulation results, we show relations between the mean waiting times of these methods and show how Capabilities 1 and 2 differently affect the mean waiting time.

  12. Performance evaluation of 10 MW grid connected solar photovoltaic power plant in India

    OpenAIRE

    B. Shiva Kumar; K. Sudhakar

    2015-01-01

    The growing energy demand in developing nations has triggered the issue of energy security. This has made essential to utilize the untapped potential of renewable resources. Grid connected PV systems have become the best alternatives in renewable energy at large scale. Performance analysis of these grid connected plants could help in designing, operating and maintenance of new grid connected systems. A 10 MW photovoltaic grid connected power plant commissioned at Ramagundam is one of the larg...

  13. Intrinsic connectivity networks from childhood to late adolescence: Effects of age and sex

    Directory of Open Access Journals (Sweden)

    Cristina Solé-Padullés

    2016-02-01

    Full Text Available There is limited evidence on the effects of age and sex on intrinsic connectivity of networks underlying cognition during childhood and adolescence. Independent component analysis was conducted in 113 subjects aged 7–18; the default mode, executive control, anterior salience, basal ganglia, language and visuospatial networks were identified. The effect of age was examined with multiple regression, while sex and ‘age × sex’ interactions were assessed by dividing the sample according to age (7–12 and 13–18 years. As age increased, connectivity in the dorsal and ventral default mode network became more anterior and posterior, respectively, while in the executive control network, connectivity increased within frontoparietal regions. The basal ganglia network showed increased engagement of striatum, thalami and precuneus. The anterior salience network showed greater connectivity in frontal areas and anterior cingulate, and less connectivity of orbitofrontal, middle cingulate and temporoparietal regions. The language network presented increased connectivity of inferior frontal and decreased connectivity within the right middle frontal and left inferior parietal cortices. The visuospatial network showed greater engagement of inferior parietal and frontal cortices. No effect of sex, nor age by sex interactions was observed. These findings provide evidence of strengthening of cortico-cortical and cortico-subcortical networks across childhood and adolescence.

  14. Effects of Neuromodulation on Excitatory-Inhibitory Neural Network Dynamics Depend on Network Connectivity Structure

    Science.gov (United States)

    Rich, Scott; Zochowski, Michal; Booth, Victoria

    2018-01-01

    Acetylcholine (ACh), one of the brain's most potent neuromodulators, can affect intrinsic neuron properties through blockade of an M-type potassium current. The effect of ACh on excitatory and inhibitory cells with this potassium channel modulates their membrane excitability, which in turn affects their tendency to synchronize in networks. Here, we study the resulting changes in dynamics in networks with inter-connected excitatory and inhibitory populations (E-I networks), which are ubiquitous in the brain. Utilizing biophysical models of E-I networks, we analyze how the network connectivity structure in terms of synaptic connectivity alters the influence of ACh on the generation of synchronous excitatory bursting. We investigate networks containing all combinations of excitatory and inhibitory cells with high (Type I properties) or low (Type II properties) modulatory tone. To vary network connectivity structure, we focus on the effects of the strengths of inter-connections between excitatory and inhibitory cells (E-I synapses and I-E synapses), and the strengths of intra-connections among excitatory cells (E-E synapses) and among inhibitory cells (I-I synapses). We show that the presence of ACh may or may not affect the generation of network synchrony depending on the network connectivity. Specifically, strong network inter-connectivity induces synchronous excitatory bursting regardless of the cellular propensity for synchronization, which aligns with predictions of the PING model. However, when a network's intra-connectivity dominates its inter-connectivity, the propensity for synchrony of either inhibitory or excitatory cells can determine the generation of network-wide bursting.

  15. Evaluating the impact of connectivity, continuity, and topography of sidewalk network on pedestrian safety.

    Science.gov (United States)

    Osama, Ahmed; Sayed, Tarek

    2017-10-01

    With the increasing demand for sustainability, walking is being encouraged as one of the main active modes of transportation. However, pedestrians are vulnerable to severe injuries when involved in crashes which can discourage road users from walking. Therefore, studying factors that affect the safety of pedestrians is important. This paper investigates the relationship between pedestrian-motorist crashes and various sidewalk network indicators in the city of Vancouver. The goal is to assess the impact of network connectivity, directness, and topography on pedestrian safety using macro-level collision prediction models. The models were developed using generalized linear regression and full Bayesian techniques. Both walking trips and vehicle kilometers travelled were used as the main traffic exposure variables in the models. The safety models supported the safety in numbers hypothesis showing a non-linear positive association between pedestrian-motorist crashes and the increase in walking trips and vehicle traffic. The model results also suggested that higher continuity, linearity, coverage, and slope of sidewalk networks were associated with lower crash occurrence. However, network connectivity was associated with higher crash occurrence. The spatial effects were accounted for in the full Bayes models and were found significant. The models provide insights about the factors that influence pedestrian safety and the spatial variability of pedestrian crashes within a city, which can be useful for the planning of pedestrian networks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Heritability of the Effective Connectivity in the Resting-State Default Mode Network.

    Science.gov (United States)

    Xu, Junhai; Yin, Xuntao; Ge, Haitao; Han, Yan; Pang, Zengchang; Liu, Baolin; Liu, Shuwei; Friston, Karl

    2017-12-01

    The default mode network (DMN) is thought to reflect endogenous neural activity, which is considered as one of the most intriguing phenomena in cognitive neuroscience. Previous studies have found that key regions within the DMN are highly interconnected. Here, we characterized the genetic influences on causal or directed information flow within the DMN during the resting state. In this study, we recruited 46 pairs of twins and collected fMRI imaging data using a 3.0 T scanner. Dynamic causal modeling was conducted for each participant, and a structural equation model was used to calculate the heritability of DMN in terms of its effective connectivity. Model comparison favored a full-connected model. Structural equal modeling was used to estimate the additive genetics (A), common environment (C) and unique environment (E) contributions to variance for the DMN effective connectivity. The ACE model was preferred in the comparison of structural equation models. Heritability of DMN effective connectivity was 0.54, suggesting that the genetic made a greater contribution to the effective connectivity within DMN. Establishing the heritability of default-mode effective connectivity endorses the use of resting-state networks as endophenotypes or intermediate phenotypes in the search for the genetic basis of psychiatric or neurological illnesses. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Monitoring Effective Connectivity in the Preterm Brain: A Graph Approach to Study Maturation

    Directory of Open Access Journals (Sweden)

    M. Lavanga

    2017-01-01

    Full Text Available In recent years, functional connectivity in the developmental science received increasing attention. Although it has been reported that the anatomical connectivity in the preterm brain develops dramatically during the last months of pregnancy, little is known about how functional and effective connectivity change with maturation. The present study investigated how effective connectivity in premature infants evolves. To assess it, we use EEG measurements and graph-theory methodologies. We recorded data from 25 preterm babies, who underwent long-EEG monitoring at least twice during their stay in the NICU. The recordings took place from 27 weeks postmenstrual age (PMA until 42 weeks PMA. Results showed that the EEG-connectivity, assessed using graph-theory indices, moved from a small-world network to a random one, since the clustering coefficient increases and the path length decreases. This shift can be due to the development of the thalamocortical connections and long-range cortical connections. Based on the network indices, we developed different age-prediction models. The best result showed that it is possible to predict the age of the infant with a root mean-squared error (MSE equal to 2.11 weeks. These results are similar to the ones reported in the literature for age prediction in preterm babies.

  18. Evaluation of a Distributed Photovoltaic System in Grid-Connected and Standalone Applications by Different MPPT Algorithms

    Directory of Open Access Journals (Sweden)

    Ru-Min Chao

    2018-06-01

    Full Text Available Due to the shortage of fossil fuel and the environmental pollution problem, solar energy applications have drawn a lot of attention worldwide. This paper reports the use of the latest patented distributed photovoltaic (PV power system design, including the two possible maximum power point tracking (MPPT algorithms, a power optimizer, and a PV power controller, in grid-connected and standalone applications. A distributed PV system with four amorphous silicon thin-film solar panels is used to evaluate both the quadratic maximization (QM and the Steepest descent (SD MPPT algorithms. The system’s design is different for the QM or the SD MPPT algorithm being used. The test result for the grid-connected silicon-based PV panels will also be reported. Considering the settling time for the power optimizer to be 20 ms, the test result shows that the tracking time for the QM method is close to 200 ms, which is faster when compared with the SD method whose tracking time is 500 ms. Besides this, the use of the QM method provides a more stable power output since the tracking is restricted by a local power optimizer rather than the global tracking the SD method uses. For a standalone PV application, a solar-powered boat design with 18 PV panels using a cascaded MPPT controller is introduced, and it provides flexibility in system design and the effective use of photovoltaic energy.

  19. Altered auditory processing and effective connectivity in 22q11.2 deletion syndrome

    DEFF Research Database (Denmark)

    Larsen, Kit Melissa; Mørup, Morten; Birknow, Michelle Rosgaard

    2018-01-01

    . Mismatch negativity (MMN), a brain marker of change detection, is reduced in people with schizophrenia compared to healthy controls. Using dynamic causal modelling (DCM), previous studies showed that top-down effective connectivity linking the frontal and temporal cortex is reduced in schizophrenia......11.2 deletion carriers. DCM showed reduced intrinsic connection within right primary auditory cortex as well as in the top-down, connection from the right inferior frontal gyrus to right superior temporal gyrus for 22q11.2 deletion carriers although not surviving correction for multiple comparison...

  20. From correlation to causation: Estimating effective connectivity from zero-lag covariances of brain signals.

    Science.gov (United States)

    Schiefer, Jonathan; Niederbühl, Alexander; Pernice, Volker; Lennartz, Carolin; Hennig, Jürgen; LeVan, Pierre; Rotter, Stefan

    2018-03-01

    Knowing brain connectivity is of great importance both in basic research and for clinical applications. We are proposing a method to infer directed connectivity from zero-lag covariances of neuronal activity recorded at multiple sites. This allows us to identify causal relations that are reflected in neuronal population activity. To derive our strategy, we assume a generic linear model of interacting continuous variables, the components of which represent the activity of local neuronal populations. The suggested method for inferring connectivity from recorded signals exploits the fact that the covariance matrix derived from the observed activity contains information about the existence, the direction and the sign of connections. Assuming a sparsely coupled network, we disambiguate the underlying causal structure via L1-minimization, which is known to prefer sparse solutions. In general, this method is suited to infer effective connectivity from resting state data of various types. We show that our method is applicable over a broad range of structural parameters regarding network size and connection probability of the network. We also explored parameters affecting its activity dynamics, like the eigenvalue spectrum. Also, based on the simulation of suitable Ornstein-Uhlenbeck processes to model BOLD dynamics, we show that with our method it is possible to estimate directed connectivity from zero-lag covariances derived from such signals. In this study, we consider measurement noise and unobserved nodes as additional confounding factors. Furthermore, we investigate the amount of data required for a reliable estimate. Additionally, we apply the proposed method on full-brain resting-state fast fMRI datasets. The resulting network exhibits a tendency for close-by areas being connected as well as inter-hemispheric connections between corresponding areas. In addition, we found that a surprisingly large fraction of more than one third of all identified connections were of

  1. Universal relationship connecting various two-body effective residual interactions

    International Nuclear Information System (INIS)

    Knuepfer, W.; Huber, M.G.

    1976-01-01

    Starting from a momentum space analysis of the two-body matrix elements, a relation has been established between the size of the model space actually used in a specific calculation and the relevant properties of the effective residual interaction. It turns out that the two-body transition density acts like a filter function on the Fourier transform of the force; it exhibits a distinct structure which clearly reflects the size and the detailed properties of the configuration space actually used. From an investigation of this filter function an equivalence criterion for different effective residual two-body interactions has been established both for closed and open shell nuclei. This result can be used to construct simple although realistic effective forces. As an example, a model for a separable residual interaction is proposed in which the corresponding parameters are being clearly related to the nuclear radius (i.e., the mass number), to the quantum numbers (i.e., the angular momentum) of the state under consideration and to the size of the configuration space used. For a number of examples this force has been applied successfully for the description of low energy properties of both closed and open shell nuclei

  2. Axial displacement of external and internal implant-abutment connection evaluated by linear mixed model analysis.

    Science.gov (United States)

    Seol, Hyon-Woo; Heo, Seong-Joo; Koak, Jai-Young; Kim, Seong-Kyun; Kim, Shin-Koo

    2015-01-01

    To analyze the axial displacement of external and internal implant-abutment connection after cyclic loading. Three groups of external abutments (Ext group), an internal tapered one-piece-type abutment (Int-1 group), and an internal tapered two-piece-type abutment (Int-2 group) were prepared. Cyclic loading was applied to implant-abutment assemblies at 150 N with a frequency of 3 Hz. The amount of axial displacement, the Periotest values (PTVs), and the removal torque values(RTVs) were measured. Both a repeated measures analysis of variance and pattern analysis based on the linear mixed model were used for statistical analysis. Scanning electron microscopy (SEM) was used to evaluate the surface of the implant-abutment connection. The mean axial displacements after 1,000,000 cycles were 0.6 μm in the Ext group, 3.7 μm in the Int-1 group, and 9.0 μm in the Int-2 group. Pattern analysis revealed a breakpoint at 171 cycles. The Ext group showed no declining pattern, and the Int-1 group showed no declining pattern after the breakpoint (171 cycles). However, the Int-2 group experienced continuous axial displacement. After cyclic loading, the PTV decreased in the Int-2 group, and the RTV decreased in all groups. SEM imaging revealed surface wear in all groups. Axial displacement and surface wear occurred in all groups. The PTVs remained stable, but the RTVs decreased after cyclic loading. Based on linear mixed model analysis, the Ext and Int-1 groups' axial displacements plateaued after little cyclic loading. The Int-2 group's rate of axial displacement slowed after 100,000 cycles.

  3. Biocompatibility Evaluation of EndoSequence Root Repair Paste in the Connective Tissue of Rats.

    Science.gov (United States)

    Taha, Nessrin A; Safadi, Rima A; Alwedaie, Manal S

    2016-10-01

    The aim of this study was to evaluate the subcutaneous connective tissue response to EndoSequence root repair paste (Brasseler, Savannah, GA) compared with mineral trioxide aggregate (MTA). Thirty-six Wistar rats each received 3 sterile tubes, containing 1 of the tested materials and control. The animals were killed 1, 3 and 6 weeks after implantation. The specimens were evaluated histologically for type of inflammation, intensity and extent of inflammatory cells, foreign body reaction, fibrous capsule thickness, perivascular fragments, calcific deposits and vascular congestion. EndoSequence provoked severe inflammation after 1 week, which was significantly different from MTA and control (P ˂ .05), with fragmented particles and foreign body reaction. MTA showed tissue-tolerance features almost comparable to control. EndoSequence was significantly more irritating than MTA and control at 1 and 3 weeks in terms of severity and extent of inflammation. After 6 weeks it displayed more biocompatible characteristics. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. Connecting Past with Present: A Mixed-Methods Science Ethics Course and its Evaluation.

    Science.gov (United States)

    Semendeferi, Ioanna; Tsiamyrtzis, Panagiotis; Dcosta, Malcolm; Pavlidis, Ioannis

    2016-02-01

    We present a graduate science ethics course that connects cases from the historical record to present realities and practices in the areas of social responsibility, authorship, and human/animal experimentation. This content is delivered with mixed methods, including films, debates, blogging, and practicum; even the instructional team is mixed, including a historian of science and a research scientist. What really unites all of the course's components is the experiential aspect: from acting in historical debates to participating in the current scientific enterprise. The course aims to change the students' culture into one deeply devoted to the science ethics cause. To measure the sought after cultural change, we developed and validated a relevant questionnaire. Results of this questionnaire from students who took the course, demonstrate that the course had the intended effect on them. Furthermore, results of this questionnaire from controls indicate the need for cultural change in that cohort. All these quantitative results are reinforced by qualitative outcomes.

  5. Conservation of connectivity of model-space effective interactions under a class of similarity transformation

    International Nuclear Information System (INIS)

    Duan Changkui; Gong Yungui; Dong Huining; Reid, Michael F.

    2004-01-01

    Effective interaction operators usually act on a restricted model space and give the same energies (for Hamiltonian) and matrix elements (for transition operators, etc.) as those of the original operators between the corresponding true eigenstates. Various types of effective operators are possible. Those well defined effective operators have been shown to be related to each other by similarity transformation. Some of the effective operators have been shown to have connected-diagram expansions. It is shown in this paper that under a class of very general similarity transformations, the connectivity is conserved. The similarity transformation between Hermitian and non-Hermitian Rayleigh-Schroedinger perturbative effective operators is one of such transformations and hence the connectivity can be deducted from each other

  6. Conservation of connectivity of model-space effective interactions under a class of similarity transformation.

    Science.gov (United States)

    Duan, Chang-Kui; Gong, Yungui; Dong, Hui-Ning; Reid, Michael F

    2004-09-15

    Effective interaction operators usually act on a restricted model space and give the same energies (for Hamiltonian) and matrix elements (for transition operators, etc.) as those of the original operators between the corresponding true eigenstates. Various types of effective operators are possible. Those well defined effective operators have been shown to be related to each other by similarity transformation. Some of the effective operators have been shown to have connected-diagram expansions. It is shown in this paper that under a class of very general similarity transformations, the connectivity is conserved. The similarity transformation between Hermitian and non-Hermitian Rayleigh-Schrodinger perturbative effective operators is one of such transformations and hence the connectivity can be deducted from each other.

  7. [Is there a connection between biodiversity and the greenhouse effect].

    Science.gov (United States)

    Rozanov, S I

    1998-01-01

    It was discussed the role of biodiversity in ecosystems capacity to control CO2 in atmosphere as the main reason not only of "greenhouse effect" but "greenhouse catastrophe". The necessity to perfect the preventive measures has been defined by time factor. This time may be so little for completing the evolution theory and models of biosphere management. The temps of contemporaneous species extinction exceed two orders as minimum ones how it has been known from planet history. It doesn't permit to discharge that evolutional process will be successful to create organisms which have been capable to stabilize biosphere in conditions of its changing status. It's possible that such change may be provocated with the crisis in civilization-biosphere interrelations.

  8. Effects of microgravity on rat bone, cartlage and connective tissues

    Science.gov (United States)

    Doty, S.

    1990-01-01

    The response to hypogravity by the skeletal system was originally thought to be the result of a reduction in weight bearing. Thus a reduced rate of new bone formation in the weight-bearing bones was accepted, when found, as an obvious result of hypogravity. However, data on non-weight-bearing tissues have begun to show that other physiological changes can be expected to occur to animals during spaceflight. This overview of the Cosmos 1887 data discusses these results as they pertain to individual bones or tissues because the response seems to depend on the architecture and metabolism of each tissue under study. Various effects were seen in different tissues from the rats flown on Cosmos 1887. The femur showed a reduced bone mineral content but only in the central region of the diaphysis. This same region in the tibia showed changes in the vascularity of bone as well as some osteocytic cell death. The humerus demonstrated reduced morphometric characteristics plus a decrease in mechanical stiffness. Bone mineral crystals did not mature normally as a result of flight, suggesting a defect in the matrix mineralization process. Note that these changes relate directly to the matrix portion of the bone or some function of bone which slowly responds to changes in the environment. However, most cellular functions of bone are rapid responders. The stimulation of osteoblast precursor cells, the osteoblast function in collagen synthesis, a change in the proliferation rate of cells in the epiphyseal growth plate, the synthesis and secretion of osteocalcin, and the movement of water into or out of tissues, are all processes which respond to environmental change. These rapidly responding events produced results from Cosmos 1887 which were frequently quite different from previous space flight data.

  9. Teacher Evaluation: Archiving Teaching Effectiveness

    Science.gov (United States)

    Nielsen, Lance D.

    2014-01-01

    Teacher evaluation is a current hot topic within music education. This article offers strategies for K-12 music educators on how to promote their effectiveness as teachers through archival documentation in a teacher portfolio. Using the Danielson evaluation model (based on four domains of effective teaching practices), examples of music teaching…

  10. Effect of neural connectivity on autocovariance and cross covariance estimates

    Directory of Open Access Journals (Sweden)

    Stecker Mark M

    2007-01-01

    important to interpret measured auto and cross covariance functions cautiously in light of the long range nature of the electric fields. Using recording electrodes that are bipolar or quadrupolar minimizes or eliminates these effects and hence these electrodes are preferred when electrical recordings are made for the purpose of auto and cross correlation analysis of local electrical activity.

  11. Multidetector CT evaluation of total anomalous pulmonary venous connections: comparison with echocardiography

    International Nuclear Information System (INIS)

    Oh, Ki Ho; Choo, Ki Seok; Lim, Soo Jin; Lee, Hyoung Doo; Park, Ji Ae; Jo, Min Jung; Sung, Si Chan; Chang, Yun Hee; Jeong, Dong Wook; Kim, Siho

    2009-01-01

    Although echocardiography is the first-line imaging modality in the diagnosis of total anomalous pulmonary venous connection (TAPVC), multidetector CT (MDCT) could have advantages in the diagnosis of TAPVC in certain cases. To compare MDCT with echocardiography in the evaluation of TAPVC. Enrolled in the study were 23 patients with surgically proven TAPVC. The echocardiography and MDCT findings were independently interpreted by a paediatric cardiologist and cardiac radiologist in terms of: (1) the drainage site of the common pulmonary vein, (2) stenosis of the vertical vein, and (3) the course of the atypical vessel into the systemic vein in the case of vertical vein stenosis. The findings from both modalities were correlated with the results obtained at surgery (n=22) or autopsy (n=1). In all patients, MDCT correctly depicted the drainage site of the common pulmonary vein, stenosis of the vertical vein and the course of the atypical vessel into the systemic vein (sensitivity 100%, specificity 100%). The specificity of echocardiography was 100% for the three defined findings. The sensitivity of echocardiography, however, was 87%, 71% and 0%, respectively. MDCT can facilitate the diagnosis of TAPVC in certain cases. (orig.)

  12. Evaluation small scale, grid connected wind and solar distributed generation systems in Jordan

    International Nuclear Information System (INIS)

    Naji, G. J.; Tahboub, K. K.; Jalham, I. S.

    2011-01-01

    In this paper, the potential of utilizing wind and solar Private Distributed Generation (PDG) for utility interactive systems is investigated for 11 selected stations (sites) in Jordan. Six customer categories are considered: residential, office, commercial mall, school, hospital and hotel. The main goal of this study was to evaluate the potential of utilizing different grid connected PDG under different conditions such as their location, size, served building category, number of people who share and own the equipment and system type whether wind, solar or hybrid based. It was found that solar systems are still not attractive for all location due to their associated high cost, while wind systems would vary widely depending on the customer category, location and the size of the equipment. Based on the Benefit to Cost ratio criterion, the most attractive sites for installing wind PDGS for residential communities are Ras Muneef, Mafraq, Aqaba, Irbid and H5, while it doesn't seem attractive at Amman,Shoubak, Ghor Essafi, Deir Alla, Maan and H4. On the other hand, the wind on-grid PDGS is very attractive at Ras Muneef, mafraq and Aqaba for commercial buildings, less attractive at H5 and irbid, while it's not attractive at the other sites. The attraction for hybrid PDG systems is closer to those of wind systems alone. (authors).

  13. Evaluation of alteration in mucogingival line location following use of subepithelial connective tissue graft

    Directory of Open Access Journals (Sweden)

    Saber Fariba

    2010-01-01

    Full Text Available Aim and Objective : The aim of this study is to evaluate the positional changes that occur in mucogingival line following the use of subepithelial connective tissue graft (SCTG. Materials and Methods : In 19 Miller class I or II gingival recession defects, distance between mucogingival line (MGL and cemento-enamel junction, also width of keratinized and attached gingiva, and clinical attachment level were measured. SCTG were used for covering the exposed roots. A fore mentioned parameters were repeated at 3, 6 and 12 months after surgery and alterations were measured. Paired t test was used to analyze the results. Results : MGL had been moved in coronal direction (4.39 ± 0.77 mm on average during surgical approach. After 1 year, MGL shifted 2.11 ± 0.7 mm apically. In accordance with this apical shift, a significant increase in the width of keratinized and attached gingival width (2.89 ± 0.63 mm and 2.82 ± 0.5 mm, respectively was seen (P < 0.05. Conclusion : MGL tended to revert back to its original position following the use of SCTG, and this reversion is accompanied with an increase in the keratinized and attached gingival width.

  14. Filter Effectiveness Evaluation

    Science.gov (United States)

    2013-08-01

    synthetic paraffinic kerosene (SPK), as well as Ultra Low Sulfur Diesel (ULSD) treated with mono-olein to simulate the effects of biodiesel . Results...fuel. Sufficient analysis and qualification of filter products is becoming increasingly crucial in ground transportation vehicles to promote the...well as a simulated biodiesel composed of ultra low sulfur diesel (ULSD) and mono-olein. As written in the scope of work, the alternative aviation

  15. Reading in dyslexia across literacy development: A longitudinal study of effective connectivity.

    Science.gov (United States)

    Morken, Frøydis; Helland, Turid; Hugdahl, Kenneth; Specht, Karsten

    2017-01-01

    Dyslexia is a literacy disorder affecting the efficient acquisition of reading and writing skills. The disorder is neurobiological in origin. Due to its developmental nature, longitudinal studies of dyslexia are of essence. They are, however, relatively scarce. The present study took a longitudinal approach to cortical connectivity of brain imaging data in reading tasks in children with dyslexia and children with typical reading development. The participants were followed with repeated measurements through Pre-literacy (6 years old), Emergent Literacy (8 years old) and Literacy (12 years old) stages, using Dynamic Causal Modelling (DCM) when analysing functional magnetic resonance imaging (fMRI) data. Even though there are a few longitudinal studies on effective connectivity in typical reading, to our knowledge, no studies have previously investigated these issues in relation to dyslexia. We set up a model of a brain reading network involving five cortical regions (inferior frontal gyrus, precentral gyrus, superior temporal gyrus, inferior parietal lobule, and occipito-temporal cortex). Using DCM, connectivity measures were calculated for each connection in the model. These measures were further analysed using factorial ANOVA. The results showed that the difference between groups centred on connections going to and from the inferior frontal gyrus (two connections) and the occipito-temporal cortex (three connections). For all five connections, the typical group showed stable or decreasing connectivity measures. The dyslexia group, on the other hand, showed a marked up-regulation (occipito-temporal connections) or down-regulation (inferior frontal gyrus connections) from 6 years to 8 years, followed by normalization from 8 years to 12 years. We interpret this as a delay in the dyslexia group in developing into the Pre-literacy and Emergent literacy stages. This delay could possibly be detrimental to literacy development. By age 12, there was no statistically

  16. Truncation effects in connected arrays: Analytical models to describe the edge-induced wave phenomena

    NARCIS (Netherlands)

    Neto, A.; Cavallo, D.; Gerini, G.

    2011-01-01

    This paper presents a Green's function based procedure to assess edge effects in finite wideband connected arrays. Truncation effects are more severe in broadband arrays, since the inter-element mutual coupling facilitates the propagation of edge-born waves that can become dominant over large

  17. Making Connections

    Science.gov (United States)

    Pien, Cheng Lu; Dongsheng, Zhao

    2011-01-01

    Effective teaching includes enabling learners to make connections within mathematics. It is easy to accord with this statement, but how often is it a reality in the mathematics classroom? This article describes an approach in "connecting equivalent" fractions and whole number operations. The authors illustrate how a teacher can combine a common…

  18. Long-term effects of ionizing radiation on the rat spinal cord: intramedullary connective tissue formation

    International Nuclear Information System (INIS)

    Gilmore, S.A.

    1973-01-01

    Light microscopy was used to evaluate the effects of ionizing radiation on spinal cords of rats irradiated when three days of age and killed at intervals up to 28 months after irradiation. The amounts of x-rays administered (2,000 R; 1,000 R; 500 R) were those which had been demonstrated by short-term studies to cause either no histopathologic changes or only transient, reparable alterations. The most significant and previously unreported finding was the development, usually restricted to the gray matter, of elongated, spindle-shaped cells that produce prodigious amounts of fibers clearly demonstrated by the Wilder's reticular stain. In cases where extensive cellular development had occurred, these cells were oriented around the perikarya of the large ventral motor neurons and formed a well-developed capsule of reticular fibers. This phenomenon occurred more frequently in rats receiving the greater amounts of radiation and killed 12 months or more after exposure. The other observation of interest was the development of lesser amounts of connective tissue-producing cells in the dorsal gray matter, where these cells were seen initially in the substantia gelatinosa. The significance of these changes is discussed in relation to previously reported long-term effects of ionizing radiation on the central nervous system

  19. Multiple effects of hydrological connectivity on floodplain processes in human modified river systems

    Science.gov (United States)

    Hein, Thomas; Bondar-Kunze, Elisabeth; Preiner, Stefan; Reckendorfer, Walter; Tritthart, Michael; Weigelhofer, Gabriele; Welti, Nina

    2014-05-01

    Floodplain and riparian ecosystems provide multiple functions and services of importance for human well-being and are of strategic importance for different sectors at catchment scale. Especially floodplains in the vicinity of urban areas can be areas of conflicting interests ranging from different land use types, flood water retention, drinking water production and recreation to conservation of last remnants of former riverine landscape, as it is the case in floodplains in the Danube Nationalpark downstream Vienna. Many of these ecosystem functions and services are controlled by the exchange conditions between river main channel and floodplain systems, the hydrological connectivity. At the same time these systems have been highly altered and especially the connectivity has been severely impaired. Thus, far ranging effects of changes in hydrological connectivity at various levels can be expected in altered floodplain systems. The aim of this presentation is to explore the complex control of different ecosystem functions and associated services by different parameters of hydrological connectivity, ranging from nutrient, sediment and matter dynamics and biodiversity aspects. Increasing connectivity will be shown to impact microbial dynamics, sediment-water interactions, carbon dynamics and trophic conditions, thus affecting the fundamental functions of particular floodplain systems at various spatial and temporal scales. Based on these changes also the provision of ecosystem services of floodplains is affected. The results clearly show that hydrological connectivity needs to be considered in a sustainable management approach.

  20. The effects of habitat connectivity and regional heterogeneity on artificial pond metacommunities.

    Science.gov (United States)

    Pedruski, Michael T; Arnott, Shelley E

    2011-05-01

    Habitat connectivity and regional heterogeneity represent two factors likely to affect biodiversity across different spatial scales. We performed a 3 × 2 factorial design experiment to investigate the effects of connectivity, heterogeneity, and their interaction on artificial pond communities of freshwater invertebrates at the local (α), among-community (β), and regional (γ) scales. Despite expectations that the effects of connectivity would depend on levels of regional heterogeneity, no significant interactions were found for any diversity index investigated at any spatial scale. While observed responses of biodiversity to connectivity and heterogeneity depended to some extent on the diversity index and spatial partitioning formula used, the general pattern shows that these factors largely act at the β scale, as opposed to the α or γ scales. We conclude that the major role of connectivity in aquatic invertebrate communities is to act as a homogenizing force with relatively little effect on diversity at the α or γ levels. Conversely, heterogeneity acts as a force maintaining differences between communities.

  1. Interhemispheric connectivity influences the degree of modulation of TMS-induced effects during auditory processing

    Directory of Open Access Journals (Sweden)

    Jamila eAndoh

    2011-07-01

    Full Text Available Repetitive TMS (rTMS has been shown to interfere with many components of language processing, including semantic, syntactic and phonologic. However, not much is known about its effects on primary auditory processing, especially its action on Heschl’s gyrus (HG. We aimed to investigate the behavioural and neural basis of rTMS during a melody processing task, while targeting the left HG, the right HG and the Vertex as a control site. Response Times (RT were normalized relative to the baseline-rTMS (Vertex and expressed as percentage change from baseline (%RT change. We also looked at sex differences in rTMS-induced response as well as in functional connectivity during melody processing using rTMS and functional Magnetic Resonance Imaging (fMRI.Functional MRI results showed an increase in the right HG compared with the left HG during the melody task, as well as sex differences in functional connectivity indicating a greater interhemispheric connectivity between left and right HG in females compared with males. TMS results showed that 10Hz-rTMS targeting the right HG induced differential effects according to sex, with a facilitation of performance in females and an impairment of performance in males. We also found a differential correlation between the %RT change after 10Hz-rTMS targeting the right HG and the interhemispheric functional connectivity between right and left HG, indicating that an increase in interhemispheric functional connectivity was associated with a facilitation of performance. This is the first study to report a differential rTMS-induced interference with melody processing depending on sex. In addition, we showed a relationship between the interference induced by rTMS on behavioral performance and the neural activity in the network connecting left and right HG, suggesting that the interhemispheric functional connectivity could determine the degree of modulation of behavioral performance.

  2. A Framework for Evaluating Energy and Emissions of Connected and Automated Vehicles through Traffic Microsimulations

    Science.gov (United States)

    2018-01-07

    Connected and automated vehicles (CAV) are poised to transform surface transportation systems in the United States. Near-term CAV technologies like cooperative adaptive cruise control (CACC) have the potential to deliver energy efficiency and air qua...

  3. Laterality effects in functional connectivity of the angular gyrus during rest and episodic retrieval.

    Science.gov (United States)

    Bellana, Buddhika; Liu, Zhongxu; Anderson, John A E; Moscovitch, Morris; Grady, Cheryl L

    2016-01-08

    The angular gyrus (AG) is consistently reported in neuroimaging studies of episodic memory retrieval and is a fundamental node within the default mode network (DMN). Its specific contribution to episodic memory is debated, with some suggesting it is important for the subjective experience of episodic recollection, rather than retrieval of objective episodic details. Across studies of episodic retrieval, the left AG is recruited more reliably than the right. We explored functional connectivity of the right and left AG with the DMN during rest and retrieval to assess whether connectivity could provide insight into the nature of this laterality effect. Using data from the publically available 1000 Functional Connectome Project, 8min of resting fMRI data from 180 healthy young adults were analysed. Whole-brain functional connectivity at rest was measured using a seed-based Partial Least Squares (seed-PLS) approach (McIntosh and Lobaugh, 2004) with bilateral AG seeds. A subsequent analysis used 6-min of rest and 6-min of unconstrained, silent retrieval of autobiographical events from a new sample of 20 younger adults. Analysis of this dataset took a more targeted approach to functional connectivity analysis, consisting of univariate pairwise correlations restricted to nodes of the DMN. The seed-PLS analysis resulted in two Latent Variables that together explained ~86% of the shared cross-block covariance. The first LV revealed a common network consistent with the DMN and engaging the AG bilaterally, whereas the second LV revealed a less robust, yet significant, laterality effect in connectivity - the left AG was more strongly connected to the DMN. Univariate analyses of the second sample again revealed better connectivity between the left AG and the DMN at rest. However, during retrieval the left AG was more strongly connected than the right to non-medial temporal (MTL) nodes of the DMN, and MTL nodes were more strongly connected to the right AG. The multivariate

  4. Validation of color Doppler sonography for evaluating relative displacement between the flexor tendon and subsynovial connective tissue.

    Science.gov (United States)

    Tat, Jimmy; Kociolek, Aaron M; Keir, Peter J

    2015-04-01

    A common pathologic finding in carpal tunnel syndrome is fibrosis and thickening of the subsynovial connective tissue. This finding suggests an etiology of excessive shear forces, with relative longitudinal displacement between the flexor tendon and adjacent subsynovial connective tissue. The purpose of this study was to validate color Doppler sonography for measurement of tendon displacement over time. Eight unmatched fresh frozen cadaver arms were used to evaluate color Doppler sonography for measurement of tendon displacement. The middle flexor digitorum superficialis tendon was moved through a physiologic excursion of 20 mm at 3 different tendon velocities (50, 100, and 150 mm/s). We found that color Doppler sonography provided accurate measurement of tendon displacement, with absolute errors of -0.05 mm (50 mm/s), -1.24 mm (100 mm/s), and -2.36 mm (150 mm/s) on average throughout the tendon excursion range. Evaluating relative displacement between the tendon and subsynovial connective tissue during finger flexion-extension movements also offered insight into the gliding mechanism of the subsynovial connective tissue. During flexion, we observed a curvilinear increase in relative displacement, with greater differential motion at the end range of displacement, likely due to the sequential stretch of the fibrils between successive layers of the subsynovial connective tissue. In extension, there was a linear return in relative displacement, suggesting a different unloading mechanism characterized by uniform relaxation of fibrils. We demonstrated the validity of color Doppler displacement for use in the evaluation of relative motion. Color Doppler sonography is useful in our understanding of the behavior of the subsynovial connective tissue during tendon excursion, which may elucidate the role of finger motion in the etiology of shear injury. © 2015 by the American Institute of Ultrasound in Medicine.

  5. Optical Fiber Connection Navigation System Using Visible Light Communication in Central Office with Economic Evaluation

    Science.gov (United States)

    Waki, Masaki; Uruno, Shigenori; Ohashi, Hiroyuki; Manabe, Tetsuya; Azuma, Yuji

    We propose an optical fiber connection navigation system that uses visible light communication for an integrated distribution module in a central office. The system realizes an accurate database, requires less skilled work to operate and eliminates human error. This system can achieve a working time reduction of up to 88.0% compared with the conventional work without human error for the connection/removal of optical fiber cords, and is economical as regards installation and operation.

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

    Science.gov (United States)

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

    2014-01-01

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

  7. Seismic Response of 3D Steel Buildings considering the Effect of PR Connections and Gravity Frames

    Directory of Open Access Journals (Sweden)

    Alfredo Reyes-Salazar

    2014-01-01

    Full Text Available The nonlinear seismic responses of 3D steel buildings with perimeter moment resisting frames (PMRF and interior gravity frames (IGF are studied explicitly considering the contribution of the IGF. The effect on the structural response of the stiffness of the beam-to-column connections of the IGF, which is usually neglected, is also studied. It is commonly believed that the flexibility of shear connections is negligible and that 2D models can be used to properly represent 3D real structures. The results of the study indicate, however, that the moments developed on columns of IGF can be considerable and that modeling buildings as plane frames may result in very conservative designs. The contribution of IGF to the lateral structural resistance may be significant. The contribution increases when their connections are assumed to be partially restrained (PR. The incremented participation of IGF when the stiffness of their connections is considered helps to counteract the no conservative effect that results in practice when lateral seismic loads are not considered in IGF while designing steel buildings with PMRF. Thus, if the structural system under consideration is used, the three-dimensional model should be used in seismic analysis and the IGF and the stiffness of their connections should be considered as part of the lateral resistance system.

  8. Altered effective connectivity within default mode network in major depression disorder

    Science.gov (United States)

    Li, Liang; Li, Baojuan; Bai, Yuanhan; Wang, Huaning; Zhang, Linchuan; Cui, Longbiao; Lu, Hongbing

    2016-03-01

    Understanding the neural basis of Major Depressive Disorder (MDD) is important for the diagnosis and treatment of this mental disorder. The default mode network (DMN) is considered to be highly involved in the MDD. To find directed interaction between DMN regions associated with the development of MDD, the effective connectivity within the DMN of the MDD patients and matched healthy controls was estimated by using a recently developed spectral dynamic causal modeling. Sixteen patients with MDD and sixteen matched healthy control subjects were included in this study. While the control group underwent the resting state fMRI scan just once, all patients underwent resting state fMRI scans before and after two months' treatment. The spectral dynamic causal modeling was used to estimate directed connections between four DMN nodes. Statistical analysis on connection strengths indicated that efferent connections from the medial frontal cortex (MFC) to posterior cingulate cortex (PCC) and to right parietal cortex (RPC) were significant higher in pretreatment MDD patients than those of the control group. After two-month treatment, the efferent connections from the MFC decreased significantly, while those from the left parietal cortex (LPC) to MFC, PCC and RPC showed a significant increase. These findings suggest that the MFC may play an important role for inhibitory conditioning of the DMN, which was disrupted in MDD patients. It also indicates that disrupted suppressive function of the MFC could be effectively restored after two-month treatment.

  9. Seismic Response of 3D Steel Buildings considering the Effect of PR Connections and Gravity Frames

    Science.gov (United States)

    Haldar, Achintya; López-Barraza, Arturo; Rivera-Salas, J. Luz

    2014-01-01

    The nonlinear seismic responses of 3D steel buildings with perimeter moment resisting frames (PMRF) and interior gravity frames (IGF) are studied explicitly considering the contribution of the IGF. The effect on the structural response of the stiffness of the beam-to-column connections of the IGF, which is usually neglected, is also studied. It is commonly believed that the flexibility of shear connections is negligible and that 2D models can be used to properly represent 3D real structures. The results of the study indicate, however, that the moments developed on columns of IGF can be considerable and that modeling buildings as plane frames may result in very conservative designs. The contribution of IGF to the lateral structural resistance may be significant. The contribution increases when their connections are assumed to be partially restrained (PR). The incremented participation of IGF when the stiffness of their connections is considered helps to counteract the no conservative effect that results in practice when lateral seismic loads are not considered in IGF while designing steel buildings with PMRF. Thus, if the structural system under consideration is used, the three-dimensional model should be used in seismic analysis and the IGF and the stiffness of their connections should be considered as part of the lateral resistance system. PMID:24995357

  10. The comparative roles of connected and disconnected trajectories in the evaluation of the semiclassical coherent-state propagator

    International Nuclear Information System (INIS)

    Rubin, A.; Klauder, J.R.

    1995-01-01

    The semiclassical approximation of the coherent-state propagator developed by Klauder and subsequently modified by Adachi is applied to the quartic oscillator. This approximation involves classical trajectories which must satisfy complex boundary conditions. It is found that these complex classical trajectories fall into two broad categories basically characterized by the descriptive titles ''continuously connected'' and ''disconnected'' given to the two different types. The continuously connected type is found to always contribute in the evaluation of the semiclassical propagator while the disconnected type will only contribute under specific conditions. copyright 1995 Academic Press, Inc

  11. The Connections Between Team Emotional Intelligence and Team Effectiveness in Financial Services - Case X Oyj

    OpenAIRE

    Peltola, Maija

    2016-01-01

    The increasing need for growing effectiveness in companies dealing with challenges of globalized markets has heightened the need for research on what makes work groups or teams more effective. Since the 1990's the concept of emotional intelligence has intrigued researchers in the field of both psychology and business economics. Recently, there has been growing interest in studying the connections between emotional intelligence and effectiveness or performance. Emotional intelligence has been ...

  12. Effect of wind generation system types on Micro-Grid (MG) fault performance during both standalone and grid connected modes

    International Nuclear Information System (INIS)

    Kamel, Rashad M.

    2014-01-01

    Highlights: • This paper evaluated the effects of different wind system types on fault performance of Micro-Grid. • Both standalone and grid connected modes are considered. • The MG earthing system configuration is taken in consideration. - Abstract: Recently, there are three wind generation (WG) system types. The first type is called Fixed Speed Wind Generation (FSWG) system, which employs squirrel cage induction generators. Double Fed Induction Generator (DFIG) is utilized in the second type. The third type is called Full Converter Wind Generation (FCWG) system, which is interfaced with Micro-Grid (MG) through a back to back converter. During fault occurrence, each WG has its performance and characteristics which are determined by the generator physical characteristics and the MG earthing system configuration. For some WG types, the fault current depends also on the control algorithm of the power converter. The main target of this paper is to investigate and estimate how the fault performance of MG during both standalone and grid-connected modes is influenced by the type of WG. It is found during standalone mode that the type of the employed WG has a dominant impact on the MG performance under fault disturbance. On the contrary, the type of the employed WG has a negligible effect on the MG fault performance during grid-connected mode. This is because the main grid contributes most of the fault current. Effects of earthing system type on MG performance are highlighted

  13. Systematic drug safety evaluation based on public genomic expression (Connectivity Map) data: myocardial and infectious adverse reactions as application cases.

    Science.gov (United States)

    Wang, Kejian; Weng, Zuquan; Sun, Liya; Sun, Jiazhi; Zhou, Shu-Feng; He, Lin

    2015-02-13

    Adverse drug reaction (ADR) is of great importance to both regulatory agencies and the pharmaceutical industry. Various techniques, such as quantitative structure-activity relationship (QSAR) and animal toxicology, are widely used to identify potential risks during the preclinical stage of drug development. Despite these efforts, drugs with safety liabilities can still pass through safety checkpoints and enter the market. This situation raises the concern that conventional chemical structure analysis and phenotypic screening are not sufficient to avoid all clinical adverse events. Genomic expression data following in vitro drug treatments characterize drug actions and thus have become widely used in drug repositioning. In the present study, we explored prediction of ADRs based on the drug-induced gene-expression profiles from cultured human cells in the Connectivity Map (CMap) database. The results showed that drugs inducing comparable ADRs generally lead to similar CMap expression profiles. Based on such ADR-gene expression association, we established prediction models for various ADRs, including severe myocardial and infectious events. Drugs with FDA boxed warnings of safety liability were effectively identified. We therefore suggest that drug-induced gene expression change, in combination with effective computational methods, may provide a new dimension of information to facilitate systematic drug safety evaluation. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The Effective Connectivity Between the Two Primary Motor Areas in the Brain during Bilateral Tapping of Hand Fingers

    Science.gov (United States)

    Yusoff, A. N.; Hamid, K. A.

    Dynamic causal modeling (DCM) was implemented on datasets obtained from an externally-triggered finger tapping functional MRI experiment performed by 5 male and female subjects. The objective was to model the effective connectivity between two significantly activated primary motor regions (M1). The left and right hemisphere M1s are found to be effectively and bidirectionally connected to each other. Both connections are modulated by the stimulus-free contextual input. These connectivities are however not gated (influenced) by any of the two M1s, ruling out the possibility of the non-linear behavior of connections between both M1s. A dynamic causal model was finally suggested.

  15. [Scale effect of Nanjing urban green infrastructure network pattern and connectivity analysis.

    Science.gov (United States)

    Yu, Ya Ping; Yin, Hai Wei; Kong, Fan Hua; Wang, Jing Jing; Xu, Wen Bin

    2016-07-01

    Based on ArcGIS, Erdas, GuidosToolbox, Conefor and other software platforms, using morphological spatial pattern analysis (MSPA) and landscape connectivity analysis methods, this paper quantitatively analysed the scale effect, edge effect and distance effect of the Nanjing urban green infrastructure network pattern in 2013 by setting different pixel sizes (P) and edge widths in MSPA analysis, and setting different dispersal distance thresholds in landscape connectivity analysis. The results showed that the type of landscape acquired based on the MSPA had a clear scale effect and edge effect, and scale effects only slightly affected landscape types, whereas edge effects were more obvious. Different dispersal distances had a great impact on the landscape connectivity, 2 km or 2.5 km dispersal distance was a critical threshold for Nanjing. When selecting the pixel size 30 m of the input data and the edge wide 30 m used in the morphological model, we could get more detailed landscape information of Nanjing UGI network. Based on MSPA and landscape connectivity, analysis of the scale effect, edge effect, and distance effect on the landscape types of the urban green infrastructure (UGI) network was helpful for selecting the appropriate size, edge width, and dispersal distance when developing these networks, and for better understanding the spatial pattern of UGI networks and the effects of scale and distance on the ecology of a UGI network. This would facilitate a more scientifically valid set of design parameters for UGI network spatiotemporal pattern analysis. The results of this study provided an important reference for Nanjing UGI networks and a basis for the analysis of the spatial and temporal patterns of medium-scale UGI landscape networks in other regions.

  16. Resting state functional MRI in Parkinson's disease: the impact of deep brain stimulation on 'effective' connectivity.

    Science.gov (United States)

    Kahan, Joshua; Urner, Maren; Moran, Rosalyn; Flandin, Guillaume; Marreiros, Andre; Mancini, Laura; White, Mark; Thornton, John; Yousry, Tarek; Zrinzo, Ludvic; Hariz, Marwan; Limousin, Patricia; Friston, Karl; Foltynie, Tom

    2014-04-01

    Depleted of dopamine, the dynamics of the parkinsonian brain impact on both 'action' and 'resting' motor behaviour. Deep brain stimulation has become an established means of managing these symptoms, although its mechanisms of action remain unclear. Non-invasive characterizations of induced brain responses, and the effective connectivity underlying them, generally appeals to dynamic causal modelling of neuroimaging data. When the brain is at rest, however, this sort of characterization has been limited to correlations (functional connectivity). In this work, we model the 'effective' connectivity underlying low frequency blood oxygen level-dependent fluctuations in the resting Parkinsonian motor network-disclosing the distributed effects of deep brain stimulation on cortico-subcortical connections. Specifically, we show that subthalamic nucleus deep brain stimulation modulates all the major components of the motor cortico-striato-thalamo-cortical loop, including the cortico-striatal, thalamo-cortical, direct and indirect basal ganglia pathways, and the hyperdirect subthalamic nucleus projections. The strength of effective subthalamic nucleus afferents and efferents were reduced by stimulation, whereas cortico-striatal, thalamo-cortical and direct pathways were strengthened. Remarkably, regression analysis revealed that the hyperdirect, direct, and basal ganglia afferents to the subthalamic nucleus predicted clinical status and therapeutic response to deep brain stimulation; however, suppression of the sensitivity of the subthalamic nucleus to its hyperdirect afferents by deep brain stimulation may subvert the clinical efficacy of deep brain stimulation. Our findings highlight the distributed effects of stimulation on the resting motor network and provide a framework for analysing effective connectivity in resting state functional MRI with strong a priori hypotheses.

  17. Evaluations of the Overjustification Effect

    Science.gov (United States)

    Peters, Kerri P.; Vollmer, Timothy R.

    2014-01-01

    The utility of reinforcement-based procedures has been well established in the behavior analysis literature and is commonly used in educational settings. However, the overjustification effect is one commonly cited criticism of programs that use tangible items as reinforcers. In the current studies, we evaluated the effects of tangible rewards…

  18. The Effects of Taekwondo Training on Brain Connectivity and Body Intelligence.

    Science.gov (United States)

    Kim, Young Jae; Cha, Eun Joo; Kim, Sun Mi; Kang, Kyung Doo; Han, Doug Hyun

    2015-07-01

    Many studies have reported that Taekwondo training could improve body perception, control and brain activity, as assessed with an electroencephalogram. This study aimed to assess body intelligence and brain connectivity in children with Taekwondo training as compared to children without Taekwondo training. Fifteen children with Taekwondo training (TKD) and 13 age- and sex-matched children who had no previous experience of Taekwondo training (controls) were recruited. Body intelligence, clinical characteristics and brain connectivity in all children were assessed with the Body Intelligence Scale (BIS), self-report, and resting state functional magnetic resonance imaging. The mean BIS score in the TKD group was higher than that in the control group. The TKD group showed increased low-frequency fluctuations in the right frontal precentral gyrus and the right parietal precuneus, compared to the control group. The TKD group showed positive cerebellum vermis (lobe VII) seed to the right frontal, left frontal, and left parietal lobe. The control group showed positive cerebellum seed to the left frontal, parietal, and occipital cortex. Relative to the control group, the TKD group showed increased functional connectivity from cerebellum seed to the right inferior frontal gyrus. To the best of our knowledge, this is the first study to assess the effect of Taekwondo training on brain connectivity in children. Taekwondo training improved body intelligence and brain connectivity from the cerebellum to the parietal and frontal cortex.

  19. Functional and effective whole brain connectivity using magnetoencephalography to identify monozygotic twin pairs.

    Science.gov (United States)

    Demuru, M; Gouw, A A; Hillebrand, A; Stam, C J; van Dijk, B W; Scheltens, P; Tijms, B M; Konijnenberg, E; Ten Kate, M; den Braber, A; Smit, D J A; Boomsma, D I; Visser, P J

    2017-08-29

    Resting-state functional connectivity patterns are highly stable over time within subjects. This suggests that such 'functional fingerprints' may have strong genetic component. We investigated whether the functional (FC) or effective (EC) connectivity patterns of one monozygotic twin could be used to identify the co-twin among a larger sample and determined the overlap in functional fingerprints within monozygotic (MZ) twin pairs using resting state magnetoencephalography (MEG). We included 32 cognitively normal MZ twin pairs from the Netherlands Twin Register who participate in the EMIF-AD preclinAD study (average age 68 years). Combining EC information across multiple frequency bands we obtained an identification rate over 75%. Since MZ twin pairs are genetically identical these results suggest a high genetic contribution to MEG-based EC patterns, leading to large similarities in brain connectivity patterns between two individuals even after 60 years of life or more.

  20. Learning effective connectivity from fMRI using autoregressive hidden Markov model with missing data.

    Science.gov (United States)

    Dang, Shilpa; Chaudhury, Santanu; Lall, Brejesh; Roy, Prasun Kumar

    2017-02-15

    Effective connectivity (EC) analysis of neuronal groups using fMRI delivers insights about functional-integration. However, fMRI signal has low-temporal resolution due to down-sampling and indirectly measures underlying neuronal activity. The aim is to address above issues for more reliable EC estimates. This paper proposes use of autoregressive hidden Markov model with missing data (AR-HMM-md) in dynamically multi-linked (DML) framework for learning EC using multiple fMRI time series. In our recent work (Dang et al., 2016), we have shown how AR-HMM-md for modelling single fMRI time series outperforms the existing methods. AR-HMM-md models unobserved neuronal activity and lost data over time as variables and estimates their values by joint optimization given fMRI observation sequence. The effectiveness in learning EC is shown using simulated experiments. Also the effects of sampling and noise are studied on EC. Moreover, classification-experiments are performed for Attention-Deficit/Hyperactivity Disorder subjects and age-matched controls for performance evaluation of real data. Using Bayesian model selection, we see that the proposed model converged to higher log-likelihood and demonstrated that group-classification can be performed with higher cross-validation accuracy of above 94% using distinctive network EC which characterizes patients vs. The full data EC obtained from DML-AR-HMM-md is more consistent with previous literature than the classical multivariate Granger causality method. The proposed architecture leads to reliable estimates of EC than the existing latent models. This framework overcomes the disadvantage of low-temporal resolution and improves cross-validation accuracy significantly due to presence of missing data variables and autoregressive process. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. A graph-theory framework for evaluating landscape connectivity and conservation planning.

    Science.gov (United States)

    Minor, Emily S; Urban, Dean L

    2008-04-01

    Connectivity of habitat patches is thought to be important for movement of genes, individuals, populations, and species over multiple temporal and spatial scales. We used graph theory to characterize multiple aspects of landscape connectivity in a habitat network in the North Carolina Piedmont (U.S.A). We compared this landscape with simulated networks with known topology, resistance to disturbance, and rate of movement. We introduced graph measures such as compartmentalization and clustering, which can be used to identify locations on the landscape that may be especially resilient to human development or areas that may be most suitable for conservation. Our analyses indicated that for songbirds the Piedmont habitat network was well connected. Furthermore, the habitat network had commonalities with planar networks, which exhibit slow movement, and scale-free networks, which are resistant to random disturbances. These results suggest that connectivity in the habitat network was high enough to prevent the negative consequences of isolation but not so high as to allow rapid spread of disease. Our graph-theory framework provided insight into regional and emergent global network properties in an intuitive and visual way and allowed us to make inferences about rates and paths of species movements and vulnerability to disturbance. This approach can be applied easily to assessing habitat connectivity in any fragmented or patchy landscape.

  2. Performance evaluation of 10 MW grid connected solar photovoltaic power plant in India

    Directory of Open Access Journals (Sweden)

    B. Shiva Kumar

    2015-11-01

    Full Text Available The growing energy demand in developing nations has triggered the issue of energy security. This has made essential to utilize the untapped potential of renewable resources. Grid connected PV systems have become the best alternatives in renewable energy at large scale. Performance analysis of these grid connected plants could help in designing, operating and maintenance of new grid connected systems. A 10 MW photovoltaic grid connected power plant commissioned at Ramagundam is one of the largest solar power plants with the site receiving a good average solar radiation of 4.97 kW h/m2/day and annual average temperature of about 27.3 degrees centigrade. The plant is designed to operate with a seasonal tilt. In this study the solar PV plant design aspects along with its annual performance is elaborated. The various types of power losses (temperature, internal network, power electronics, grid connected etc. and performance ratio are also calculated. The performance results of the plant are also compared with the simulation values obtained from PV syst and PV-GIS software. The final yield (Y F of plant ranged from 1.96 to 5.07 h/d, and annual performance ratio (PR of 86.12%. It has 17.68% CUF with annual energy generation of 15798.192 MW h/Annum.

  3. Comprehensive evaluation of anomalous pulmonary venous connection by electron beam computed tomography as compared with ultrasound

    International Nuclear Information System (INIS)

    Zhang Shaoxiong; Dai Ruping; Bai Hua; He Sha; Jing Baolian

    1999-01-01

    Objective: To investigate the clinical value of electron beam computed tomography (EBCT) in diagnosis of anomalous pulmonary venous connection. Methods: Retrospective analysis on 14 cases with anomalous pulmonary venous connection was performed using EBCT volume scan. The slice thickness and scan time were 3 mm and 100 ms respectively. Non-ionic contrast medium was applied. Three dimensional reconstruction of EBCT images were carried out on all cases. Meanwhile, ultrasound echocardiography was performed on all patients. Conventional cardiovascular angiography was performed on 8 patients and 2 cases received operation. Results: Ten patients with total anomalous pulmonary venous connection, including 6 cases of supra-cardiac type and 4 cases of cardiac type, were proved by EBCT examination. Among them, 3 cases of abnormal pulmonary venous drainage were not revealed by conventional cardiovascular angiography. Among four patients with partial pulmonary venous connection, including cardiac type in 2 cases, supra-cardiac type and infra-cardiac type in 1 case respectively, only one of them was demonstrated by echocardiography. Conclusion: EBCT has significant value in diagnosis of anomalous pulmonary venous connection which may not be detectable with echocardiography or even cardiovascular angiography

  4. Cortical brain connectivity evaluated by graph theory in dementia: a correlation study between functional and structural data.

    Science.gov (United States)

    Vecchio, Fabrizio; Miraglia, Francesca; Curcio, Giuseppe; Altavilla, Riccardo; Scrascia, Federica; Giambattistelli, Federica; Quattrocchi, Carlo Cosimo; Bramanti, Placido; Vernieri, Fabrizio; Rossini, Paolo Maria

    2015-01-01

    A relatively new approach to brain function in neuroscience is the "functional connectivity", namely the synchrony in time of activity in anatomically-distinct but functionally-collaborating brain regions. On the other hand, diffusion tensor imaging (DTI) is a recently developed magnetic resonance imaging (MRI)-based technique with the capability to detect brain structural connection with fractional anisotropy (FA) identification. FA decrease has been observed in the corpus callosum of subjects with Alzheimer's disease (AD) and mild cognitive impairment (MCI, an AD prodromal stage). Corpus callosum splenium DTI abnormalities are thought to be associated with functional disconnections among cortical areas. This study aimed to investigate possible correlations between structural damage, measured by MRI-DTI, and functional abnormalities of brain integration, measured by characteristic path length detected in resting state EEG source activity (40 participants: 9 healthy controls, 10 MCI, 10 mild AD, 11 moderate AD). For each subject, undirected and weighted brain network was built to evaluate graph core measures. eLORETA lagged linear connectivity values were used as weight of the edges of the network. Results showed that callosal FA reduction is associated to a loss of brain interhemispheric functional connectivity characterized by increased delta and decreased alpha path length. These findings suggest that "global" (average network shortest path length representing an index of how efficient is the information transfer between two parts of the network) functional measure can reflect the reduction of fiber connecting the two hemispheres as revealed by DTI analysis and also anticipate in time this structural loss.

  5. Common effects of amnestic mild cognitive impairment on resting-state connectivity across four independent studies

    Directory of Open Access Journals (Sweden)

    Angela eTam

    2015-12-01

    Full Text Available Resting-state functional connectivity is a promising biomarker for Alzheimer’s disease. However, previous resting-state functional magnetic resonance imaging studies in Alzheimer’s disease and amnestic mild cognitive impairment (aMCI have shown limited reproducibility as they have had small sample sizes and substantial variation in study protocol. We sought to identify functional brain networks and connections that could consistently discriminate normal aging from aMCI despite variations in scanner manufacturer, imaging protocol, and diagnostic procedure. We therefore combined four datasets collected independently, including 112 healthy controls and 143 patients with aMCI. We systematically tested multiple brain connections for associations with aMCI using a weighted average routinely used in meta-analyses. The largest effects involved the superior medial frontal cortex (including the anterior cingulate, dorsomedial prefrontal cortex, striatum, and middle temporal lobe. Compared with controls, patients with aMCI exhibited significantly decreased connectivity between default mode network nodes and between regions of the cortico-striatal-thalamic loop. Despite the heterogeneity of methods among the four datasets, we identified common aMCI-related connectivity changes with small to medium effect sizes and sample size estimates recommending a minimum of 140 to upwards of 600 total subjects to achieve adequate statistical power in the context of a multisite study with 5-10 scanning sites and about 10 subjects per group and per site. If our findings can be replicated and associated with other established biomarkers of Alzheimer’s disease (e.g. amyloid and tau quantification, then these functional connections may be promising candidate biomarkers for Alzheimer’s disease.

  6. The effects of patch shape and connectivity on nest site selection and reproductive success of the Indigo Bunting.

    Energy Technology Data Exchange (ETDEWEB)

    Weldon, Aimee Jean

    2004-07-01

    Description – Ph.D Dissertation. North Carolina State University. Raleigh, North Carolina. 135 pp. Abatract - Habitat fragmentation and its associated effects have been blamed for the recent population declines of many Neotropical migratory bird species. Increased predation and parasitism resulting from edge-related effects have been implicated for poor nesting success in many studies, mostly of forest interior species. However, little attention has been devoted to disturbance-dependent birds. In this study, I examine how patch shape and connectivity in fragmented landscapes affects the reproductive success of disturbance-dependent bird species, specifically the Indigo Bunting (Passerina cyanea). I conducted my study in a landscape-scale experimental system of similar-area habitat patches that differed in connectivity and in shape. Shapes differed between edgy and rectangular forms, where edgy patches contained 50% more edge than rectangular patches. I tested whether edgy patches function as ecological traps for species with strong edge preferences, by leading them to select dangerous habitats. Indigo Buntings preferentially selected edgy patches over rectangular patches, but experienced significantly lower reproductive success in edgy patches early in the season. Although predation pressure intensified in rectangular patches late in the season, seasonal fecundity was still significantly lower in edgy patches, providing the first empirical evidence that edges can function as ecological traps for Indigo Buntings. A second objective of my study was to evaluate the efficacy of conservation corridors for disturbance-dependent bird species. Conservation corridors have become a popular strategy to preserve biodiversity and promote gene flow in fragmented landscapes, but corridors may also have negative consequences. I tested the hypothesis that corridors can increase nest predation risk in connected patches relative to unconnected patches. Nest predation rates

  7. A free tool integrating GIS features and workflows to evaluate sediment connectivity in alpine catchments

    Science.gov (United States)

    Crema, Stefano; Schenato, Luca; Goldin, Beatrice; Marchi, Lorenzo; Cavalli, Marco

    2014-05-01

    The increased interest in sediment connectivity has brought the geomorphologists' community to focus on sediment fluxes as a key process (Cavalli et al., 2013; Heckmann and Schwanghart, 2013). The challenge of dealing with erosion-related processes in alpine catchments is of primary relevance for different fields of investigations and applications, including, but not limited to natural hazards, hydraulic structures design, ecology and stream restoration. The present work focuses on the development of a free tool for sediment connectivity assessment as described in Cavalli et al. (2013), introducing some novel improvements. The choice of going for a free software is motivated by the need of widening the access and improving participation beyond the restrictions on algorithms customization, typical of commercial software. A couple of features further enhance the tool: being completely free and adopting a user-friendly interface, its target audience includes researchers and stakeholders (e.g., local managers and civil protection authorities in charge of planning the priorities of intervention in the territory), being written in Python programming language, it can benefit from optimized algorithms for high-resolution DEMs (Digital Elevation Models) handling and for propagation workflows implementation; these two factors make the tool computationally competitive with the most recent commercial GIS products. The overall goal of this tool is supporting the analysis of sediment connectivity, facing the challenge of widening, as much as possible, the users' community among scientists and stakeholders. This aspect is crucial, as future improvement of this tool will benefit of feedbacks from users in order to improve the quantitative assessment of sediment connectivity as a major input information for the optimal management of mountain areas. References: Cavalli, M., Trevisani, S., Comiti, F., Marchi, L., 2013. Geomorphometric assessment of spatial sediment connectivity in

  8. Performance evaluation of a 2-mode PV grid connected system in Thailand -- Case study

    Energy Technology Data Exchange (ETDEWEB)

    Jivacate, C.; Mongconvorawan, S.; Sinratanapukdee, E.; Limsawatt, W. [Electricity Generating Authority of Thailand, Nontha Buri (Thailand)

    1994-12-31

    A PV grid connected system with small battery bank has been set up in a rural district, North Thailand in order to demonstrate a 2-mode operation concept. The objective is to gain experience on the PV grid connected concept without battery storage. However, due to the evening peak demand and a rather weak distribution grid which is typical in rural areas, small battery bank is still required to enable the maximum energy transfer to grid for the time being before moving fully to the no battery mode. The analyzed data seems to indicate possible performance improvement by re-arranging the number of PV modules and battery in the string.

  9. Experimental evaluation of 8kW grid-connected photovoltaic system in Egypt

    OpenAIRE

    Elkholy, A.; Fahmy, F.H.; Abou El-Ela, A.A.; Nafeh, Abd El-Shafy A.; Spea, S.R.

    2016-01-01

    An experimental observation study of 8 kW grid-connected photovoltaic (PV) system that is installed at Electronics Research Institute (ERI), Giza, Egypt (Latitude 30.04°N, Longitude 31.21°E), is presented. This study includes the quality of the electrical power generated and injected into the network. The considered system consists of 28 × 295 Wp multicrystalline PV modules, StecaGrid three-phase 8 kW grid-connected inverter and a Solar-Log 300 PM+ for data acquisition and remote monitoring. ...

  10. Reliability evaluation of linear multi-state consecutively-connected systems constrained by m consecutive and n total gaps

    International Nuclear Information System (INIS)

    Yu, Huan; Yang, Jun; Peng, Rui; Zhao, Yu

    2016-01-01

    This paper extends the linear multi-state consecutively-connected system (LMCCS) to the case of LMCCS-MN, where MN denotes the dual constraints of m consecutive gaps and n total gaps. All the nodes are distributed along a line and form a sequence. The distances between the adjacent nodes are usually non-uniform. The nodes except the last one can contain statistically independent multi-state connection elements (MCEs). Each MCE can provide a connection between the node at which it is located and the next nodes along the sequence. The LMCCS-MN fails if it meets either of the two constraints. The universal generating function technique is adopted to evaluate the system reliability. The optimal allocations of LMCCS-MN with two different types of failures are solved by genetic algorithm. Finally, two examples are given for the demonstration of the proposed model. - Highlights: • A new model of multi-state consecutively-connected system (LMCCS-MN) is proposed. • The non-uniform distributed nodes are involved in the proposed LMCCS-MN model. • An algorithm for system reliability evaluation is provided by the UGF method. • The computational complexity of the proposed algorithm is discussed in detail. • Optimal element allocation problem is formulated and solved.

  11. Quantum oscillation and the Aharonov-Bohm effect in a multiply connected normal-conductor loop

    Science.gov (United States)

    Takai, Daisuke; Ohta, Kuniichi

    1994-12-01

    The magnetostatic and electrostatic Aharonov-Bohm (AB) effects in multiply connected normal-conductor rings are studied. A previously developed model of a single mesoscopic ring is generalized to include an arbitrary number of rings, and the oscillatory behavior of the total transmission coefficients for the serially connected N (N is equal to integer) rings are derived as a function of the magnetic flux threading each ring and as a function of the electrostatic potential applied to the rings. It is shown that quantum oscillation of multiple rings exhibits greater variety of behavior than in periodic superlattices. We investigate the influence of the scattering at a junction and the number of atoms in the ring in both magnetostatic and electrostatic oscillation of multiring systems. For the electrostatic AB effects, when scattering occurs at the junctions between the connecting wire and the ring, the conductance in the AB oscillation is modified to an N-1 peaked shape. It is shown that this oscillatory behavior is greatly influenced by the number of atoms in the ring and is controlled by the electrostatic potential or magnetic flux that is applied to the ring. We discuss the behavior of the quantum oscillations upon varying the number of connected rings and the number of minibands.

  12. Effects of mechanical massage, manual lymphatic drainage and connective tissue manipulation techniques on fat mass in women with cellulite.

    Science.gov (United States)

    Bayrakci Tunay, V; Akbayrak, T; Bakar, Y; Kayihan, H; Ergun, N

    2010-02-01

    To evaluate and compare the effectiveness of three different noninvasive treatment techniques on fat mass and regional fat thickness of the patients with cellulites. Sixty subjects were randomized into three groups. Group 1 (n = 20) treated with mechanical massage (MM), group 2 (n = 20) treated with manual lymphatic drainage (MLD) and group 3 (n = 20) treated with connective tissue manipulation (CTM) techniques. Subjects were evaluated by using standardized photographs, body composition analyzer (TBF 300) (body weight (BW), body mass index (BMI), fat %, fat mass (FM), fat free mass (FFM), total body water (TBW)), circumference measurement from thigh, waist-hip ratio (WHR), fat thickness measurements from abdomen, suprailium and thigh regions with skin fold caliper. All groups had an improvement in thinning of the subcutaneous fat after the treatment (P techniques are effective in decreasing the regional fat values of the patients with cellulites.

  13. Performance evaluation and validation of 5 MWp grid connected solar photovoltaic plant in South India

    International Nuclear Information System (INIS)

    Sundaram, Sivasankari; Babu, Jakka Sarat Chandra

    2015-01-01

    Highlights: • A real time performance analysis with validation of the system is carried out for 5 MW p plant. • Dependence or interactions of input factors over performance responses are identified. • The topology of the PV system and the inverter technology is suggested for improved realization. • The average PV module, inverter and system efficiency are found to be 6.08%, 88.2% and 5.08%. • Average energy and exergy efficiency of the system is found to be 6.08% and 3.54%. - Abstract: The main objective of this paper is to present the validated annual performance analysis with the monitored results from a 5 MW p grid connected photovoltaic plant located in India at Sivagangai district in Tamilnadu. The total annual energy generated was 8495296.4 kW h which averages around 707941.4 kW h/month. In addition to the above, real time performance of the plant is validated through system software called RETscreen plus which employs regression analysis for validation. The measured annual average energy generated by the 5 MW p system is 24116.61 kW h/day which is appropriately close to the predicted annual average which was found to be 24055.25 kW h/day by RETscreen. The predicted responses are further justified by the value of statistical indicators such as mean bias error, root mean square error and mean percentage error. The annual average daily array yield, corrected reference yield, final yield, module efficiency, inverter efficiency and system efficiency were found to be 5.46 h/day, 5.128 h/day 4.810 h/day, 6.08%, 88.20% and 5.08% respectively. The overall absolute average daily capture loss and system loss of the particular system under study is 0.384 h/day and 0.65 h/day respectively. A comparison is also made between the performance indices of solar photovoltaic system situated at other locations from the literature’s published. Furthermore the effect of input factors over the output of the system is emphasized by regression coefficients obtained

  14. Systematic drug safety evaluation based on public genomic expression (Connectivity Map) data: Myocardial and infectious adverse reactions as application cases

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Kejian, E-mail: kejian.wang.bio@gmail.com [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China); Weng, Zuquan [Japan National Institute of Occupational Safety and Health, Kawasaki (Japan); Sun, Liya [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China); Sun, Jiazhi; Zhou, Shu-Feng [Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL (United States); He, Lin, E-mail: helin@Bio-X.com [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China)

    2015-02-13

    Adverse drug reaction (ADR) is of great importance to both regulatory agencies and the pharmaceutical industry. Various techniques, such as quantitative structure–activity relationship (QSAR) and animal toxicology, are widely used to identify potential risks during the preclinical stage of drug development. Despite these efforts, drugs with safety liabilities can still pass through safety checkpoints and enter the market. This situation raises the concern that conventional chemical structure analysis and phenotypic screening are not sufficient to avoid all clinical adverse events. Genomic expression data following in vitro drug treatments characterize drug actions and thus have become widely used in drug repositioning. In the present study, we explored prediction of ADRs based on the drug-induced gene-expression profiles from cultured human cells in the Connectivity Map (CMap) database. The results showed that drugs inducing comparable ADRs generally lead to similar CMap expression profiles. Based on such ADR-gene expression association, we established prediction models for various ADRs, including severe myocardial and infectious events. Drugs with FDA boxed warnings of safety liability were effectively identified. We therefore suggest that drug-induced gene expression change, in combination with effective computational methods, may provide a new dimension of information to facilitate systematic drug safety evaluation. - Highlights: • Drugs causing common toxicity lead to similar in vitro gene expression changes. • We built a model to predict drug toxicity with drug-specific expression profiles. • Drugs with FDA black box warnings were effectively identified by our model. • In vitro assay can detect severe toxicity in the early stage of drug development.

  15. Systematic drug safety evaluation based on public genomic expression (Connectivity Map) data: Myocardial and infectious adverse reactions as application cases

    International Nuclear Information System (INIS)

    Wang, Kejian; Weng, Zuquan; Sun, Liya; Sun, Jiazhi; Zhou, Shu-Feng; He, Lin

    2015-01-01

    Adverse drug reaction (ADR) is of great importance to both regulatory agencies and the pharmaceutical industry. Various techniques, such as quantitative structure–activity relationship (QSAR) and animal toxicology, are widely used to identify potential risks during the preclinical stage of drug development. Despite these efforts, drugs with safety liabilities can still pass through safety checkpoints and enter the market. This situation raises the concern that conventional chemical structure analysis and phenotypic screening are not sufficient to avoid all clinical adverse events. Genomic expression data following in vitro drug treatments characterize drug actions and thus have become widely used in drug repositioning. In the present study, we explored prediction of ADRs based on the drug-induced gene-expression profiles from cultured human cells in the Connectivity Map (CMap) database. The results showed that drugs inducing comparable ADRs generally lead to similar CMap expression profiles. Based on such ADR-gene expression association, we established prediction models for various ADRs, including severe myocardial and infectious events. Drugs with FDA boxed warnings of safety liability were effectively identified. We therefore suggest that drug-induced gene expression change, in combination with effective computational methods, may provide a new dimension of information to facilitate systematic drug safety evaluation. - Highlights: • Drugs causing common toxicity lead to similar in vitro gene expression changes. • We built a model to predict drug toxicity with drug-specific expression profiles. • Drugs with FDA black box warnings were effectively identified by our model. • In vitro assay can detect severe toxicity in the early stage of drug development

  16. Evaluation of Extended Wall OSB Sheathing Connection under Combined Uplift and Shear Loading for 24-inch Heel Trusses

    Science.gov (United States)

    Vladimir Kochkin; Andrew DeRenzis; Xiping Wang

    2014-01-01

    This study was designed to evaluate the performance of the extended wall structural panel connection in resisting combined uplift and shear forces at the roof-to-wall interface with a focus on a truss heel height of 24 in. to address the expected increases in the depth of attic insulation used in Climate Zones 5 and higher. Five full-size roof-wall assemblies were...

  17. An Evaluation of the Left-Brain vs. Right-Brain Hypothesis with Resting State Functional Connectivity Magnetic Resonance Imaging

    OpenAIRE

    Nielsen, Jared A.; Zielinski, Brandon A.; Ferguson, Michael A.; Lainhart, Janet E.; Anderson, Jeffrey S.

    2013-01-01

    Lateralized brain regions subserve functions such as language and visuospatial processing. It has been conjectured that individuals may be left-brain dominant or right-brain dominant based on personality and cognitive style, but neuroimaging data has not provided clear evidence whether such phenotypic differences in the strength of left-dominant or right-dominant networks exist. We evaluated whether strongly lateralized connections covaried within the same individuals. Data were analyzed from...

  18. Effects of Early and Late Bilingualism on Resting-State Functional Connectivity.

    Science.gov (United States)

    Berken, Jonathan A; Chai, Xiaoqian; Chen, Jen-Kai; Gracco, Vincent L; Klein, Denise

    2016-01-27

    Of current interest is how variations in early language experience shape patterns of functional connectivity in the human brain. In the present study, we compared simultaneous (two languages from birth) and sequential (second language learned after age 5 years) bilinguals using a seed-based resting-state MRI approach. We focused on the inferior frontal gyrus (IFG) as our ROI, as recent studies have demonstrated both neurofunctional and neurostructural changes related to age of second language acquisition in bilinguals in this cortical area. Stronger functional connectivity was observed for simultaneous bilinguals between the left and right IFG, as well as between the inferior frontal gyrus and brain areas involved in language control, including the dorsolateral prefrontal cortex, inferior parietal lobule, and cerebellum. Functional connectivity between the left IFG and the right IFG and right inferior parietal lobule was also significantly correlated with age of acquisition for sequential bilinguals; the earlier the second language was acquired, the stronger was the functional connectivity. In addition, greater functional connectivity between homologous regions of the inferior frontal gyrus was associated with reduced neural activation in the left IFG during speech production. The increased connectivity at rest and reduced neural activation during task performance suggests enhanced neural efficiency in this important brain area involved in both speech production and domain-general cognitive processing. Together, our findings highlight how the brain's intrinsic functional patterns are influenced by the developmental timeline in which second language acquisition occurs. Of current interest is how early life experience leaves its footprint on brain structure and function. In this regard, bilingualism provides an optimal way to determine the effects of the timing of language learning because a second language can be learned from birth or later in life. We used resting

  19. Evaluation of marginal bone loss of dental implants with internal or external connections and its association with other variables: A systematic review.

    Science.gov (United States)

    de Medeiros, Rodrigo Antonio; Pellizzer, Eduardo Piza; Vechiato Filho, Aljomar José; Dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas; Goiato, Marcelo Coelho

    2016-10-01

    Different factors can influence marginal bone loss around dental implants, including the type of internal and external connection between the implant and the abutment. The evidence needed to evaluate these factors is unclear. The purpose of this systematic review was to evaluate marginal bone loss by radiographic analysis around dental implants with internal or external connections. A systematic review was conducted following the criteria defined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Initially, a population, intervention, comparison, and outcome(s) (PICO) question was defined: does the connection type (internal or external) influence marginal bone loss in patients undergoing implantation? An electronic search of PubMed/MEDLINE and Scopus databases was performed for studies in English language published between January 2000 and December 2014 by 2 independent reviewers, who analyzed the marginal bone loss of dental implants with an internal and/or external connection. From an initial screening yield of 595 references and after considering inclusion and exclusion criteria, 17 articles were selected for this review. Among them, 10 studies compared groups of implants with internal and external connections; 1 study evaluated external connections; and 6 studies analyzed internal connections. A total of 2708 implants were placed in 864 patients. Regarding the connection type, 2347 implants had internal connections, and 361 implants had external connections. Most studies showed lower marginal bone loss values for internal connection implants than for external connection implants. Osseointegrated dental implants with internal connections exhibited lower marginal bone loss than implants with external connections. This finding is mainly the result of the platform switching concept, which is more frequently found in implants with internal connections. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry

  20. Simulating the effects of climate change on population connectivity of American marten (Martes americana) in the northern Rocky Mountains, USA

    Science.gov (United States)

    T. N. Wasserman; S. A. Cushman; A. S. Shirk; E. L. Landguth; J. S. Littell

    2012-01-01

    We utilize empirically derived estimates of landscape resistance to assess current landscape connectivity of American marten (Martes americana) in the northern Rocky Mountains, USA, and project how a warming climate may affect landscape resistance and population connectivity in the future. We evaluate the influences of five potential future temperature scenarios...

  1. 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.

  2. Evaluating IAQ effects on people

    DEFF Research Database (Denmark)

    Wyon, David; Tham, K. W.; Sekhar, C.

    2003-01-01

    "conclusive". From them, a small number of conclusions were drawn, and some very large gaps in our knowledge of this important area of research were identified. Taking these as the starting point, this paper formulates a strategy for evaluating IAQ effects on people. It formulates some critical hypotheses...

  3. Evaluation of contiguous implants with cement-retained implant-abutment connections. A minipig study

    Directory of Open Access Journals (Sweden)

    Raquel Rezende Martins de Barros

    2014-03-01

    Full Text Available Aim: The presence of a microgap at the implant-abutment interface may permit bacterial contamination and lead to bone resorption, interfering with papillae formation. The present study evaluated adjacent implants with cement-retained abutments as an option to control such deleterious effects. Materials and methods Seven minipigs had their bilateral mandibular premolars previously extracted. After 8 weeks, four implants were installed in each hemi-mandible of each animal. The adjacent implants were randomly inserted on one side at the crestal bone level and on the other, 1.5 mm subcrestally. Immediately, a non-submerged healing and functional loading were provided with the abutments cementation and prostheses installation. Clinical examination and histomorphometry served to analyze the implant success. Results A total of 52 implants were evaluated at the end of the study. The subcrestal group achieved statistical better results when compared to the crestal group, clinically in papillae formation (1.97 x 1.57 mm and histomorphometrically in crestal bone remodeling (1.17 x 1.63 mm, bone density (52.39 x 45.22% and bone-implant contact (54.13 x 42.46%. Conclusion The subcrestal placement of cement-retained abutment implants showed better indexes of osseointegration and also improved papillae formation and crestal bone remodeling at the interimplant area after immediate loading, making them a promising option for the treatment of esthetic regions.

  4. The effectiveness of community-based cycling promotion: findings from the Cycling Connecting Communities project in Sydney, Australia

    Directory of Open Access Journals (Sweden)

    Merom Dafna

    2010-01-01

    Full Text Available Abstract Background Encouraging cycling is an important way to increase physical activity in the community. The Cycling Connecting Communities (CCC Project is a community-based cycling promotion program that included a range of community engagement and social marketing activities, such as organised bike rides and events, cycling skills courses, the distribution of cycling maps of the area and coverage in the local press. The aim of the study was to assess the effectiveness of this program designed to encourage the use of newly completed off-road cycle paths through south west Sydney, Australia. Methods The evaluation used a quasi-experimental design that consisted of a pre- and post-intervention telephone survey (24 months apart of a cohort of residents (n = 909 in the intervention area (n = 520 (Fairfield and Liverpool and a socio-demographically similar comparison area (n = 389 (Bankstown. Both areas had similar bicycle infrastructure. Four bicycle counters were placed on the main bicycle paths in the intervention and comparison areas to monitor daily bicycle use before and after the intervention. Results The telephone survey results showed significantly greater awareness of the Cycling Connecting Communities project (13.5% vs 8.0%, p Conclusion Despite relatively modest resources, the Cycling Connecting Communities project achieved significant increases in bicycle path use, and increased cycling in some sub-groups. However, this community based intervention with limited funding had very limited reach into the community and did not increase population cycling levels.

  5. The Direct Effect of Flexible Walls on Fontan Connection Fluid Dynamics

    Science.gov (United States)

    Tree, Mike; Fagan, Kiley; Yoganathan, Ajit

    2014-11-01

    The current standard treatment for sufferers of congenital heart defects is the palliative Fontan procedure. The Fontan procedure results in an anastomosis of major veins directly to the branched pulmonary arteries bypassing the dysfunctional ventricle. This total cavopulmonary connection (TCPC) extends life past birth, but Fontan patients still suffer long-term complications like decreased exercise capacity, protein-losing enteropathy, and pulmonary arteriovenous malformations (PAVM). These complications have direct ties to fluid dynamics within the connection. Previous experimental and computation studies of Fontan connection fluid dynamics employed rigid vessel models. More recent studies utilize flexible models, but a direct comparison of the fundamental fluid dynamics between rigid and flexible vessels only exists for a computational model, without a direct experimental validation. Thus, this study was a direct comparison of fluid dynamics within a rigid and two compliant idealized TCPCs. 2D particle image velocimetry measurements were collected at the connection center plane. Results include power loss, hepatic flow distribution, fluid shear stress, and flow structure recognition. The effect of flexible walls on these values and clinical impact will be discussed.

  6. The effect of geometric scattering on the oscillatory magnetoconductance in multiply connected disordered mesoscopic rings

    International Nuclear Information System (INIS)

    Basu, C.; Gu Benyuan.

    1994-12-01

    We present the quantum mechanical calculations on the conductance of a quantum waveguide consisting of multiply connected mesoscopic rings with disordered ring-circumferences and ballistic lead connections between the rings with the transfer matrix approach. The profiles of the conductance as functions of the magnetic flux and the Fermi wave number of electrons depend on the number of rings as also on the geometric configuration of the system. The conductance spectrum of this system for disordered ring circumferences, disordered ring intervals and disordered magnetic flux is examined in detail. Studying the effect of geometric scattering and the two different length scales involved in the network, namely, the ring circumference and the ballistic lead connections on the conductance profile, we find that there exist two kinds of mini-bands, one originating from the bound states of the rings, i.e. the intrinsic mini-bands, and the other associated with the connecting leads between the adjacent rings, which are the extra mini-bands. These two kinds of mini-bands respond differently to external perturbations in parameters. Unlike the system of potential scatterers, this system of geometric scatterers show complete band formations at all energies even for finite systems and there is a preferential decay of the energy states depending upon the type of disorder introduced. The conductance band structures strongly depend on the geometric configuration of the network and so by controlling the geometric parameters, the conductance band structures can be artificially tailored. (author). 18 refs, 6 figs

  7. The Effect of English Verbal Songs on Connected Speech Aspects of Adult English Learners’ Speech Production

    Directory of Open Access Journals (Sweden)

    Farshid Tayari Ashtiani

    2015-02-01

    Full Text Available The present study was an attempt to investigate the impact of English verbal songs on connected speech aspects of adult English learners’ speech production. 40 participants were selected based on the results of their performance in a piloted and validated version of NELSON test given to 60 intermediate English learners in a language institute in Tehran. Then they were equally distributed in two control and experimental groups and received a validated pretest of reading aloud and speaking in English. Afterward, the treatment was performed in 18 sessions by singing preselected songs culled based on some criteria such as popularity, familiarity, amount, and speed of speech delivery, etc. In the end, the posttests of reading aloud and speaking in English were administered. The results revealed that the treatment had statistically positive effects on the connected speech aspects of English learners’ speech production at statistical .05 level of significance. Meanwhile, the results represented that there was not any significant difference between the experimental group’s mean scores on the posttests of reading aloud and speaking. It was thus concluded that providing the EFL learners with English verbal songs could positively affect connected speech aspects of both modes of speech production, reading aloud and speaking. The Findings of this study have pedagogical implications for language teachers to be more aware and knowledgeable of the benefits of verbal songs to promote speech production of language learners in terms of naturalness and fluency. Keywords: English Verbal Songs, Connected Speech, Speech Production, Reading Aloud, Speaking

  8. Effects of aging on neural connectivity underlying selective memory for emotional scenes.

    Science.gov (United States)

    Waring, Jill D; Addis, Donna Rose; Kensinger, Elizabeth A

    2013-02-01

    Older adults show age-related reductions in memory for neutral items within complex visual scenes, but just like young adults, older adults exhibit a memory advantage for emotional items within scenes compared with the background scene information. The present study examined young and older adults' encoding-stage effective connectivity for selective memory of emotional items versus memory for both the emotional item and its background. In a functional magnetic resonance imaging (fMRI) study, participants viewed scenes containing either positive or negative items within neutral backgrounds. Outside the scanner, participants completed a memory test for items and backgrounds. Irrespective of scene content being emotionally positive or negative, older adults had stronger positive connections among frontal regions and from frontal regions to medial temporal lobe structures than did young adults, especially when items and backgrounds were subsequently remembered. These results suggest there are differences between young and older adults' connectivity accompanying the encoding of emotional scenes. Older adults may require more frontal connectivity to encode all elements of a scene rather than just encoding the emotional item. Published by Elsevier Inc.

  9. Structural and effective connectivity reveals potential network-based influences on category-sensitive visual areas

    Directory of Open Access Journals (Sweden)

    Nicholas eFurl

    2015-05-01

    Full Text Available Visual category perception is thought to depend on brain areas that respond specifically when certain categories are viewed. These category-sensitive areas are often assumed to be modules (with some degree of processing autonomy and to act predominantly on feedforward visual input. This modular view can be complemented by a view that treats brain areas as elements within more complex networks and as influenced by network properties. This network-oriented viewpoint is emerging from studies using either diffusion tensor imaging to map structural connections or effective connectivity analyses to measure how their functional responses influence each other. This literature motivates several hypotheses that predict category-sensitive activity based on network properties. Large, long-range fiber bundles such as inferior fronto-occipital, arcuate and inferior longitudinal fasciculi are associated with behavioural recognition and could play crucial roles in conveying backward influences on visual cortex from anterior temporal and frontal areas. Such backward influences could support top-down functions such as visual search and emotion-based visual modulation. Within visual cortex itself, areas sensitive to different categories appear well-connected (e.g., face areas connect to object- and motion sensitive areas and their responses can be predicted by backward modulation. Evidence supporting these propositions remains incomplete and underscores the need for better integration of DTI and functional imaging.

  10. The Effect of Explicit Instruction of Connected Speech Features on Iranian EFL Learners’

    Directory of Open Access Journals (Sweden)

    Moussa Ahmadian

    2014-03-01

    Full Text Available Listening comprehension has found its right place in the field of SLA in recent decades. For years, among all language skills, speaking and writing were of high significance in teaching and learning a new language as they were considered to be productive skills. Listening and reading, on the other hand, were neglected since they were regarded as passive skills, means to other ends, rather than ends in themselves. This study investigates possible effects of explicit instruction of connected speech features on listening comprehension of Iranian English language learners. Forty adult female Persian speaking homogeneous English learners, aged 18-30, participated in the study. They were divided into two experimental and control groups. The experimental group received explicit instructions on connected speech features, while the control group followed the routine instructions designed by their institute. Tests of connected speech features were used in pre- and post tests. The participants’ scores on the pre-posttests were compared via the paired samples t-tests and independent samples t-tests. The results indicated the outperformance of the experimental group over the control group, thus, suggesting that explicit instructions of connected speech features have facilitative roles in improving EFL learners’ listening comprehension skill. Possible implications of the findings for teaching listening comprehension are discussed.

  11. Simplified method to evaluate seismic nozzle loads on mechanical equipment connected to unbraced piping

    International Nuclear Information System (INIS)

    Detroux, P.; Lafaille, J.P.

    1991-01-01

    After ten years of operation, the Belgian Nuclear Power Plants had to be seismically reassessed; especially, new requirements were imposed to the oldest units. The method, presented in this paper, is based on the principle that all the piping connected to the equipment is replaced by a clamped-hinged beam with or without concentrated mass and of a characteristic length depending on the diameter, schedule, mass per length of the connected piping and on the floor response spectra applicable at the location of the equipment. A theoretical justification of the method is presented for the simplest cases. The case of added concentrated mass is investigated. Finally, several comparisons with a full modal spectral analysis are presented

  12. A plastic collapse method for evaluating rotation capacity of full-restrained steel moment connections

    Directory of Open Access Journals (Sweden)

    Lee Kyungkoo

    2008-01-01

    Full Text Available An analytical method to model failure of steel beam plastic hinges due to local buckling and low-cycle fatigue is proposed herein. This method is based on the plastic collapse mechanism approach and a yield-line plastic hinge (YLPH model whose geometry is based on buckled shapes of beam plastic hinges observed in experiments. Two limit states, strength degradation failure induced by local buckling and low-cycle fatigue fracture, are considered. The proposed YLPH model was developed for FEMA-350 WUF-W, RBS and Free Flange connections and validated in comparisons to experimental data. This model can be used to estimate the seismic rotation capacity of fully restrained beam-column connections in special steel moment-resisting frames under both monotonic and cyclic loading conditions.

  13. Performance Evaluation of Methods for Estimating Achievable Throughput on Cellular Connections

    DEFF Research Database (Denmark)

    Mikkelsen, Lars Møller; Højholt, Nikolaj Bove; Madsen, Tatiana Kozlova

    2015-01-01

    The continuous increase in always connected devices and the advance in capabilities of networks and services offered via the network is evident. The target group of most of these devices and services is users, so how users perceive the network performance is of great importance. Estimating achiev...... AT, due to its much reduced resource consumption. Based on real-life measurements of the two methods we conclude that TOPP is a good candidate to estimate AT, based on similarity in results with BTC....

  14. Effects of Tightening Torque on Dynamic Characteristics of Low Pressure Rotors Connected by a Spline Coupling

    Institute of Scientific and Technical Information of China (English)

    Chen Xi; Liao M ingfu; Li Quankun

    2017-01-01

    A rotor dynamic model is built up for investigating the effects of tightening torque on dynamic character-istics of low pressure rotors connected by a spline coupling .The experimental rotor system is established using a fluted disk and a speed sensor which is applied in an actual aero engine for speed measurement .Through simulating calculation and experiments ,the effects of tightening torque on the dynamic characteristics of the rotor system con-nected by a spline coupling including critical speeds ,vibration modes and unbalance responses are analyzed .The results show that when increasing the tightening torque ,the first two critical speeds and the amplitudes of unbal-ance response gradually increase in varying degrees while the vibration modes are essentially unchanged .In addi-tion ,changing axial and circumferential positions of the mass unbalance can lead to various amplitudes of unbalance response and even the rates of change .

  15. Effect of voltage sags on digitally controlled line connected switched-mode power supplies

    DEFF Research Database (Denmark)

    Török, Lajos; Munk-Nielsen, Stig

    2012-01-01

    Different voltage disorders like voltage fluctuations, sags, frequency variations may occur in the power supply networks due to different fault conditions. These deviations from normal operation affects in different ways the line connected devices. Standards were developed to protect and ensure...... of voltage sags is analyzed. Fault tolerant control algorithm was designed, implemented and is discussed. The fault conditions and their effects were investigated at different power levels....

  16. The Effect of Hurricanes on Annual Precipitation in Maryland and the Connection to Global Climate Change

    Science.gov (United States)

    Liu, Jackie; Liu, Zhong

    2015-01-01

    Precipitation is a vital aspect of our lives droughts, floods and other related disasters that involve precipitation can cause costly damage in the economic system and general society. Purpose of this project is to determine what, if any effect do hurricanes have on annual precipitation in Maryland Research will be conducted on Marylands terrain, climatology, annual precipitation, and precipitation contributed from hurricanes Possible connections to climate change

  17. How music alters a kiss: superior temporal gyrus controls fusiform–amygdalar effective connectivity

    Science.gov (United States)

    Deserno, Lorenz; Bakels, Jan-Hendrik; Schlochtermeier, Lorna H.; Kappelhoff, Hermann; Jacobs, Arthur M.; Fritz, Thomas Hans; Koelsch, Stefan; Kuchinke, Lars

    2014-01-01

    While watching movies, the brain integrates the visual information and the musical soundtrack into a coherent percept. Multisensory integration can lead to emotion elicitation on which soundtrack valences may have a modulatory impact. Here, dynamic kissing scenes from romantic comedies were presented to 22 participants (13 females) during functional magnetic resonance imaging scanning. The kissing scenes were either accompanied by happy music, sad music or no music. Evidence from cross-modal studies motivated a predefined three-region network for multisensory integration of emotion, consisting of fusiform gyrus (FG), amygdala (AMY) and anterior superior temporal gyrus (aSTG). The interactions in this network were investigated using dynamic causal models of effective connectivity. This revealed bilinear modulations by happy and sad music with suppression effects on the connectivity from FG and AMY to aSTG. Non-linear dynamic causal modeling showed a suppressive gating effect of aSTG on fusiform–amygdalar connectivity. In conclusion, fusiform to amygdala coupling strength is modulated via feedback through aSTG as region for multisensory integration of emotional material. This mechanism was emotion-specific and more pronounced for sad music. Therefore, soundtrack valences may modulate emotion elicitation in movies by differentially changing preprocessed visual information to the amygdala. PMID:24298171

  18. How music alters a kiss: superior temporal gyrus controls fusiform-amygdalar effective connectivity.

    Science.gov (United States)

    Pehrs, Corinna; Deserno, Lorenz; Bakels, Jan-Hendrik; Schlochtermeier, Lorna H; Kappelhoff, Hermann; Jacobs, Arthur M; Fritz, Thomas Hans; Koelsch, Stefan; Kuchinke, Lars

    2014-11-01

    While watching movies, the brain integrates the visual information and the musical soundtrack into a coherent percept. Multisensory integration can lead to emotion elicitation on which soundtrack valences may have a modulatory impact. Here, dynamic kissing scenes from romantic comedies were presented to 22 participants (13 females) during functional magnetic resonance imaging scanning. The kissing scenes were either accompanied by happy music, sad music or no music. Evidence from cross-modal studies motivated a predefined three-region network for multisensory integration of emotion, consisting of fusiform gyrus (FG), amygdala (AMY) and anterior superior temporal gyrus (aSTG). The interactions in this network were investigated using dynamic causal models of effective connectivity. This revealed bilinear modulations by happy and sad music with suppression effects on the connectivity from FG and AMY to aSTG. Non-linear dynamic causal modeling showed a suppressive gating effect of aSTG on fusiform-amygdalar connectivity. In conclusion, fusiform to amygdala coupling strength is modulated via feedback through aSTG as region for multisensory integration of emotional material. This mechanism was emotion-specific and more pronounced for sad music. Therefore, soundtrack valences may modulate emotion elicitation in movies by differentially changing preprocessed visual information to the amygdala. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  19. An investigation into the effects of pore connectivity on T2 NMR relaxation

    Science.gov (United States)

    Ghomeshi, Shahin; Kryuchkov, Sergey; Kantzas, Apostolos

    2018-04-01

    Nuclear Magnetic Resonance (NMR) is a powerful technique used to characterize fluids and flow in porous media. The NMR relaxation curves are closely related to pore geometry, and the inversion of the NMR relaxometry data is known to give useful information with regards to pore size distribution (PSD) through the relative amplitudes of the fluids stored in the small and large pores. While this information is crucial, the main challenge for the successful use of the NMR measurements is the proper interpretation of the measured signals. Natural porous media patterns consist of complex pore structures with many interconnected or "coupled" regions, as well as isolated pores. This connectivity along the throats changes the relaxation distribution and in order to properly interpret this data, a thorough understanding of the effects of pore connectivity on the NMR relaxation distribution is warranted. In this paper we address two main points. The first pertains to the fact that there is a discrepancy between the relaxation distribution obtained from experiments, and the ones obtained from solving the mathematical models of diffusion process in the digitized images of the pore space. There are several reasons that may attribute to this such as the lack of a proper incorporation of surface roughness into the model. However, here we are more interested in the effects of pore connectivity and to understand why the typical NMR relaxation distribution obtained from experiments are wider, while the numerical simulations predict that a wider NMR relaxation distribution may indicate poor connectivity. Secondly, by not taking into account the pore coupling effects, from our experience in interpreting the data, we tend to underestimate the pore volume of small pores and overestimate the amplitudes in the large pores. The role of pore coupling becomes even more prominent in rocks with small pore sizes such as for example in shales, clay in sandstones, and in the microstructures of

  20. Network science and the effects of music preference on functional brain connectivity: from Beethoven to Eminem.

    Science.gov (United States)

    Wilkins, R W; Hodges, D A; Laurienti, P J; Steen, M; Burdette, J H

    2014-08-28

    Most people choose to listen to music that they prefer or 'like' such as classical, country or rock. Previous research has focused on how different characteristics of music (i.e., classical versus country) affect the brain. Yet, when listening to preferred music--regardless of the type--people report they often experience personal thoughts and memories. To date, understanding how this occurs in the brain has remained elusive. Using network science methods, we evaluated differences in functional brain connectivity when individuals listened to complete songs. We show that a circuit important for internally-focused thoughts, known as the default mode network, was most connected when listening to preferred music. We also show that listening to a favorite song alters the connectivity between auditory brain areas and the hippocampus, a region responsible for memory and social emotion consolidation. Given that musical preferences are uniquely individualized phenomena and that music can vary in acoustic complexity and the presence or absence of lyrics, the consistency of our results was unexpected. These findings may explain why comparable emotional and mental states can be experienced by people listening to music that differs as widely as Beethoven and Eminem. The neurobiological and neurorehabilitation implications of these results are discussed.

  1. Grid-connected ICES: preliminary feasibility analysis and evaluation. Volume 3. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-06-30

    Maps, charts, and drawings of the Demonstration Community for the grid-connected ICES project composed of the medical complex in New Orleans (HEAL) are presented in Appendix A. The physical profile of the existing buildings and site plans is included. Demand profiles for steam, electric, gas, etc. are presented in Appendix B with extensive tables and graphs. Air quality and noise pollution data are presented in Appendix C. Data on financing in Appendix D are presented and also texts and information on revenue bonds are given. The final appendix gives qualifications for personnel for HEAL; NOSPI; de Laureal Engineers, Inc.; and Orr-Schelen-Mayeron and Associates, Inc.

  2. Development and Evaluation of cooperative control system for an HVDC transmission system connected with an isolated BWR power plant

    International Nuclear Information System (INIS)

    Horiuchi, Susumu; Hara, Tsukusi; Matori, Iwao; Hirayama, Kaiichirou.

    1987-01-01

    In the cooperative control system developed for an HVDC transmission system connected with an isolated BWR power plant, the equilibrium state between power plant output and DC transmission power is examined by way of the detection of the generator frequency. And, thereby start-up and shutdown of the DC system and controlling of the transmission power are made, so that the signal transmission with the power plant becomes unnecessary, enabling the easy cooperative operation. In order to investigate validity of this control system, various digital simulation and simulator test with the control system were carried out. In this way, behavior of the power plant and stability of the DC transmission system were evaluated in the connection to the DC system at power plant start-up, follow of the transmission power in change of the power plant output and in various system failures. (Mori, K.)

  3. Evaluating a European knowledge hub on climate change in agriculture: Are we building a better connected community?

    Science.gov (United States)

    Saetnan, Eli Rudinow; Kipling, Richard Philip

    In order to maintain food security and sustainability of production under climate change, interdisciplinary and international collaboration in research is essential. In the EU, knowledge hubs are important funding instruments for the development of an interconnected European Research Area. Here, network analysis was used to assess whether the pilot knowledge hub MACSUR has affected interdisciplinary collaboration, using co-authorship of peer reviewed articles as a measure of collaboration. The broad community of all authors identified as active in the field of agriculture and climate change was increasingly well connected over the period studied. Between knowledge hub members, changes in network parameters suggest an increase in collaborative interaction beyond that expected due to network growth, and greater than that found in the broader community. Given that interdisciplinary networks often take several years to have an impact on research outputs, these changes within the relatively new MACSUR community provide evidence that the knowledge hub structure has been effective in stimulating collaboration. However, analysis showed that knowledge hub partners were initially well-connected, suggesting that the initiative may have gathered together researchers with particular resources or inclinations towards collaborative working. Long term, consistent funding and ongoing reflection to improve networking structures may be necessary to sustain the early positive signs from MACSUR, to extend its success to a wider community of researchers, or to repeat it in less connected fields of science. Tackling complex challenges such as climate change will require research structures that can effectively support and utilise the diversity of talents beyond the already well-connected core of scientists at major research institutes. But network research shows that this core, well-connected group are vital brokers in achieving wider integration.

  4. Effects of Methylphenidate on Resting-State Functional Connectivity of the Mesocorticolimbic Dopamine Pathways in Cocaine Addiction

    Energy Technology Data Exchange (ETDEWEB)

    Konova, Anna B.; Moeller, Scott J.; Tomasi, Dardo; Volkow, Nora D.; Goldstein, Rita Z.

    2013-08-01

    Cocaine addiction is associated with altered resting-state functional connectivity among regions of the mesocorticolimbic dopamine pathways. Methylphenidate hydrochloride, an indirect dopamine agonist, normalizes task-related regional brain activity and associated behavior in cocaine users; however, the neural systems–level effects of methylphenidate in this population have not yet been described. To use resting-state functional magnetic resonance imaging to examine changes in mesocorticolimbic connectivity with methylphenidate and how connectivity of affected pathways relates to severity of cocaine addiction.

  5. The Effects of Long Duration Bed Rest on Brain Functional Connectivity and Sensorimotor Functioning

    Science.gov (United States)

    Cassady, K.; Koppelmans, V.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; Castenada, R. Riascos; Kofman, I.; hide

    2016-01-01

    Long duration spaceflight has been associated with detrimental alterations in human sensorimotor functioning. Prolonged exposure to a head-down tilt (HDT) position during long duration bed rest can resemble several effects of the microgravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The question of whether microgravity affects other central nervous system functions such as brain functional connectivity and its relationship with behavior is largely unknown, but of importance to the health and performance of astronauts both during and post-flight. In the present study, we investigate the effects of prolonged exposure to HDT bed rest on resting state brain functional connectivity and its association with behavioral changes in 17 male participants. To validate that our findings were not due to confounding factors such as time or task practice, we also acquired resting state functional magnetic resonance imaging (rs-fMRI) and behavioral measurements from 14 normative control participants at four time points. Bed rest participants remained in bed with their heads tilted down six degrees below their feet for 70 consecutive days. Rs-fMRI and behavioral data were obtained at seven time points averaging around: 12 and 8 days prior to bed rest; 7, 50, and 70 days during bed rest; and 8 and 12 days after bed rest. 70 days of HDT bed rest resulted in significant increases in functional connectivity during bed rest followed by a reversal of changes in the post bed rest recovery period between motor cortical and somatosensory areas of the brain. In contrast, decreases in connectivity were observed between temporoparietal regions. Furthermore, post-hoc correlation analyses revealed a significant relationship between motor-somatosensory network connectivity and standing balance performance changes; participants that exhibited the greatest increases in connectivity strength showed the least deterioration in postural

  6. Effect of dietary docosahexaenoic acid connecting phospholipids on the lipid peroxidation of the brain in mice.

    Science.gov (United States)

    Hiratsuka, Seiichi; Ishihara, Kenji; Kitagawa, Tomoko; Wada, Shun; Yokogoshi, Hidehiko

    2008-12-01

    The effect of dietary docosahexaenoic acid (DHA, C22:6n-3) with two lipid types on lipid peroxidation of the brain was investigated in streptozotocin (STZ)-induced diabetic mice. Each group of female Balb/c mice was fed a diet containing DHA-connecting phospholipids (DHA-PL) or DHA-connecting triacylglycerols (DHA-TG) for 5 wk. Safflower oil was fed as the control. The lipid peroxide level of the brain was significantly lower in the mice fed the DHA-PL diet when compared to those fed the DHA-TG and safflower oil diets, while the alpha-tocopherol level was significantly higher in the mice fed the DHA-PL diet than in those fed the DHA-TG and safflower oil diets. The DHA level of phosphatidylethanolamine in the brain was significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil diet. The dimethylacetal levels were significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil and DHA-TG diets. These results suggest that the dietary DHA-connecting phospholipids have an antioxidant activity on the brain lipids in mice, and the effect may be related to the brain plasmalogen.

  7. Altered Effective Connectivity of Hippocampus-Dependent Episodic Memory Network in mTBI Survivors

    Directory of Open Access Journals (Sweden)

    Hao Yan

    2016-01-01

    Full Text Available Traumatic brain injuries (TBIs are generally recognized to affect episodic memory. However, less is known regarding how external force altered the way functionally connected brain structures of the episodic memory system interact. To address this issue, we adopted an effective connectivity based analysis, namely, multivariate Granger causality approach, to explore causal interactions within the brain network of interest. Results presented that TBI induced increased bilateral and decreased ipsilateral effective connectivity in the episodic memory network in comparison with that of normal controls. Moreover, the left anterior superior temporal gyrus (aSTG, the concept forming hub, left hippocampus (the personal experience binding hub, and left parahippocampal gyrus (the contextual association hub were no longer network hubs in TBI survivors, who compensated for hippocampal deficits by relying more on the right hippocampus (underlying perceptual memory and the right medial frontal gyrus (MeFG in the anterior prefrontal cortex (PFC. We postulated that the overrecruitment of the right anterior PFC caused dysfunction of the strategic component of episodic memory, which caused deteriorating episodic memory in mTBI survivors. Our findings also suggested that the pattern of brain network changes in TBI survivors presented similar functional consequences to normal aging.

  8. Estimation of effective connectivity using multi-layer perceptron artificial neural network.

    Science.gov (United States)

    Talebi, Nasibeh; Nasrabadi, Ali Motie; Mohammad-Rezazadeh, Iman

    2018-02-01

    Studies on interactions between brain regions estimate effective connectivity, (usually) based on the causality inferences made on the basis of temporal precedence. In this study, the causal relationship is modeled by a multi-layer perceptron feed-forward artificial neural network, because of the ANN's ability to generate appropriate input-output mapping and to learn from training examples without the need of detailed knowledge of the underlying system. At any time instant, the past samples of data are placed in the network input, and the subsequent values are predicted at its output. To estimate the strength of interactions, the measure of " Causality coefficient " is defined based on the network structure, the connecting weights and the parameters of hidden layer activation function. Simulation analysis demonstrates that the method, called "CREANN" (Causal Relationship Estimation by Artificial Neural Network), can estimate time-invariant and time-varying effective connectivity in terms of MVAR coefficients. The method shows robustness with respect to noise level of data. Furthermore, the estimations are not significantly influenced by the model order (considered time-lag), and the different initial conditions (initial random weights and parameters of the network). CREANN is also applied to EEG data collected during a memory recognition task. The results implicate that it can show changes in the information flow between brain regions, involving in the episodic memory retrieval process. These convincing results emphasize that CREANN can be used as an appropriate method to estimate the causal relationship among brain signals.

  9. The Effects of Music Intervention on Functional Connectivity Strength of the Brain in Schizophrenia.

    Science.gov (United States)

    Yang, Mi; He, Hui; Duan, Mingjun; Chen, Xi; Chang, Xin; Lai, Yongxiu; Li, Jianfu; Liu, Tiejun; Luo, Cheng; Yao, Dezhong

    2018-01-01

    Schizophrenia is often associated with behavior abnormality in the cognitive and affective domain. Music intervention is used as a complementary treatment for improving symptoms in patients with schizophrenia. However, the neurophysiological correlates of these remissions remain poorly understood. Here, we investigated the effects of music intervention in neural circuits through functional magnetic resonance imaging (fMRI) study in schizophrenic subjects. Under the standard care, patients were randomly assigned to music and non-music interventions (MTSZ, UMTSZ) for 1 month. Resting-state fMRI were acquired over three time points (baseline, 1 month, and 6 months later) in patients and analyzed using functional connectivity strength (FCS) and seed-based functional connection (FC) approaches. At baseline, compared with healthy controls, decreased FCS in the right middle temporal gyrus (MTG) was observed in patients. However, after music intervention, the functional circuitry of the right MTG, which was related with the function of emotion and sensorimotor, was improved in MTSZ. Furthermore, the FC increments were significantly correlated with the improvement of symptoms, while vanishing 6 months later. Together, these findings provided evidence that music intervention might positively modulate the functional connectivity of MTG in patients with schizophrenia; such changes might be associated with the observed therapeutic effects of music intervention on neurocognitive function. This trial is registered with ChiCTR-OPC-14005339.

  10. Life Cycle Assessment of Connected and Automated Vehicles: Sensing and Computing Subsystem and Vehicle Level Effects.

    Science.gov (United States)

    Gawron, James H; Keoleian, Gregory A; De Kleine, Robert D; Wallington, Timothy J; Kim, Hyung Chul

    2018-03-06

    Although recent studies of connected and automated vehicles (CAVs) have begun to explore the potential energy and greenhouse gas (GHG) emission impacts from an operational perspective, little is known about how the full life cycle of the vehicle will be impacted. We report the results of a life cycle assessment (LCA) of Level 4 CAV sensing and computing subsystems integrated into internal combustion engine vehicle (ICEV) and battery electric vehicle (BEV) platforms. The results indicate that CAV subsystems could increase vehicle primary energy use and GHG emissions by 3-20% due to increases in power consumption, weight, drag, and data transmission. However, when potential operational effects of CAVs are included (e.g., eco-driving, platooning, and intersection connectivity), the net result is up to a 9% reduction in energy and GHG emissions in the base case. Overall, this study highlights opportunities where CAVs can improve net energy and environmental performance.

  11. Evaluation of Using Triangular Plates as Continuity Plates in Box Column Section in Prequalified Welded Connections under Cyclic Loading

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Kafi

    2017-02-01

    Full Text Available Welding of Continuity plates in box columns are not easily possible, therefore some researches has been done for substitution of external continuity plates.In this study first discussed about effects of continuity plate in I beam to Box column with top and bottom plate (WFP and welded unreinforced flange-welded web connection (WUF-W and reduced beam section connection (RBS. Then, triangular plates use to in connection beam to box column as continuity plates and to consider under cyclic loading. Studies have shown that existence of continuity plates in connections mentioned above have averagely increased loading capacity, rigidity and energy absorption 63, 86 and 75 percent respectively. The results also showed that using of triangular plates as continuity plates of box columns causing plastic strain in column flange in the area that concentration of materials is not much in triangular plates and increased the probability of failure in weld of plates to the column flange. Also using of triangular plates as continuity plates have not affected on plastic hinge location.

  12. Seismic Evaluation of a Multitower Connected Building by Using Three Software Programs with Experimental Verification

    Directory of Open Access Journals (Sweden)

    Deyuan Zhou

    2016-01-01

    Full Text Available Shanghai International Design Center (SHIDC is a hybrid structure of steel frame and reinforced concrete core tube (SF-RCC. It is a building of unequal height two-tower system and the story lateral stiffness of two towers is different, which may result in the torsion effect. To fully evaluate structural behaviors of SHIDC under earthquakes, NosaCAD, ABAQUS, and Perform-3D, which are widely applied for nonlinear structure analysis, were used to perform elastoplastic time history analyses. Numerical results were compared with those of shake table testing. NosaCAD has function modules for transforming the nonlinear analysis model to Perform-3D and ABAQUS. These models were used in ABAQUS or Perform-3D directly. With the model transformation, seismic performances of SHIDC were fully investigated. Analyses have shown that the maximum interstory drift can satisfy the limits specified in Chinese code and the failure sequence of structural members was reasonable. It meant that the earthquake input energy can be well dissipated. The structure keeps in an undamaged state under frequent earthquakes and it does not collapse under rare earthquakes; therefore, the seismic design target is satisfied. The integrated use of multisoftware with the validation of shake table testing provides confidence for a safe design of such a complex structure.

  13. Evaluation of the Optimal Connection of Power Transformers in the Substations of a Hospital

    Directory of Open Access Journals (Sweden)

    Carlos Javier Renedo

    2018-02-01

    Full Text Available Transformers are installed in power distribution systems to perform changes in supply voltage. Large consumers often have several transformers installed in parallel to ensure continuity of supply in the event of failure. These machines can achieve very high efficiency, but their efficiency is not constant since it depends on the power demanded at each time. Therefore, the level of efficiency that correspond to the operation of a specific transformer depends on two factors: machine technical characteristics and electrical load. In this work, the authors have proposed a methodology which shows the optimal number of transformers to be connected at each period in the substations of a large Spanish hospital, in order to achieve the maximum seasonal efficiency of these machines. The results of the energy saving are determined with respect to the current situation, in which all the transformers are permanently connected. On the other hand, the European Union has established a new regulation that sets the minimum energy efficiency requirements for new power transformers. This efficiency improvement is proposed to be applied gradually in two stages, a first limit came into force in 2015, while a more restrictive approach will appear in the year 2021. This work has also studied the potential energy savings that would occur when the substations of the hospital have more efficient transformers complying with the new European Regulation 548/2014.

  14. Current Control and Performance Evaluation of Converter Interfaced Distribution Resources in Grid Connected Mode

    Directory of Open Access Journals (Sweden)

    SINGH Alka

    2012-10-01

    Full Text Available Use of distributed resources is growing in developing countries like India and in developed nations too. The increased acceptance of suchresources is mainly due to their modularity, increased reliability, good power quality and environment friendly operation. These are currently being interfaced to the existing systems using voltage source inverters (VSC’s. The control of such distributed resources is significantly different than the conventional power systems mainly because the VSC’s have no inertia unlike the synchronous generators.This paper deals with the Matlab modeling and design of control aspects of one such distributed source feeding a common load. A grid connected supply is also available. The control algorithm is developed for real and reactive power sharing of the load between thedistributed source and the grid. The developed control scheme is tested for linear (R-L load as well as nonlinear loads. With suitable modifications, the control algorithm can be extended for several distributed resources connected in parallel.

  15. Bupropion Shows Different Effects on Brain Functional Connectivity in Patients With Internet-Based Gambling Disorder and Internet Gaming Disorder.

    Science.gov (United States)

    Bae, Sujin; Hong, Ji Sun; Kim, Sun Mi; Han, Doug Hyun

    2018-01-01

    Internet gaming disorder (IGD) and gambling disorder (GD) share similar clinical characteristics but show different brain functional connectivity patterns. Bupropion is known to be effective for the treatment of patients with IGD and GD. We hypothesized that bupropion may be effective for the treatment of Internet-based gambling disorder (ibGD) and IGD and that the connections between the default mode network (DMN) and cognitive control network (CCN) would be different between ibGD and IGD patients after 12 weeks of bupropion treatment. 16 patients with IGD, 15 patients with ibGD, and 15 healthy subjects were recruited in this study. At baseline and after 12 weeks of bupropion treatment, the clinical symptoms of patients with IGD or ibGD were assessed, and brain activity was evaluated using resting state functional magnetic resonance imaging. After the 12-week bupropion treatment, clinical symptoms, including the severity of IGD or GD, depressive symptoms, attention, and impulsivity improved in both groups. In the IGD group, the functional connectivity (FC) within the posterior DMN as well as the FC between the DMN and the CCN decreased following treatment. Moreover, the FC within the DMN in the IGD group was positively correlated with changes in Young Internet Addiction Scale scores after the bupropion treatment period. In the ibGD group, the FC within the posterior DMN decreased while the FC within the CCN increased after the bupropion treatment period. Moreover, the FC within the CCN in the ibGD group was significantly greater than that in the IGD group. Bupropion was effective in improving clinical symptoms in patients with IGD and ibGD. However, there were differences in the pharmacodynamics between the two groups. After 12 weeks of bupropion treatment, the FC within the DMN as well as between the DMN and CCN decreased in patients with IGD, whereas the FC within the CCN increased in patients with ibGD.

  16. Clinical evaluation of expanded mesh connective tissue graft in the treatment for multiple adjacent gingival recessions in the esthetic zone

    Directory of Open Access Journals (Sweden)

    M Shanmugam

    2015-01-01

    Full Text Available Background: Multiple approaches have been used to replace lost, damaged or diseased gingival tissues. The connective tissue graft (CTG procedure is the golden standard method for root coverage. Although multiple sites often need grafting, the palatal mucosa supplies only a limited area of grafting material. To overcome this limitation, expanded mesh graft provides a method whereby a graft can be stretched to cover a large area. The aim of this study was to evaluate the effectiveness and the predictability of expanded mesh CTG (e-MCTG in the treatment of adjacent multiple gingival recessions. Materials and Methods: Sixteen patients aged 20-50 years contributed to 55 sites, each site falling into at least three adjacent Miller′s Class 1 or Class 2 gingival recession. The CTG obtained from the palatal mucosa was expanded to cover the recipient bed, which was 1.5 times larger than the graft. Clinical measurements were recorded at baseline and 3 months, 12 months postoperatively. Results: A mean coverage of 1.96 mm ± 0.66 mm and 2.22 mm ± 0.68 mm was obtained at the end of 3 rd and 12 th month, respectively. Twelve months after surgery a statistically significant increase in CAL (2.2 mm ± 0.68 mm, P < 0.001 and increasing WKT (1.75 ± 0.78, P < 0.001 were obtained. In 80% of the treated sites, 100% root coverage was achieved (mean 93.5%. Conclusions: The results of this study demonstrated that multiple adjacent recessions were treated by using e-MCTG technique can be applied and highly predictable root coverage can be achieved.

  17. Altered resting-state effective connectivity of fronto-parietal motor control systems on the primary motor network following stroke

    Science.gov (United States)

    Inman, Cory S.; James, G. Andrew; Hamann, Stephan; Rajendra, Justin K.; Pagnoni, Giuseppe; Butler, Andrew J.

    2011-01-01

    Previous brain imaging work suggests that stroke alters the effective connectivity (the influence neural regions exert upon each other) of motor execution networks. The present study examines the intrinsic effective connectivity of top-down motor control in stroke survivors (n=13) relative to healthy participants (n=12). Stroke survivors exhibited significant deficits in motor function, as assessed by the Fugl-Meyer Motor Assessment. We used structural equation modeling (SEM) of resting-state fMRI data to investigate the relationship between motor deficits and the intrinsic effective connectivity between brain regions involved in motor control and motor execution. An exploratory adaptation of SEM determined the optimal model of motor execution effective connectivity in healthy participants, and confirmatory SEM assessed stroke survivors’ fit to that model. We observed alterations in spontaneous resting-state effective connectivity from fronto-parietal guidance systems to the motor network in stroke survivors. More specifically, diminished connectivity was found in connections from the superior parietal cortex to primary motor cortex and supplementary motor cortex. Furthermore, the paths demonstrated large individual variance in stroke survivors but less variance in healthy participants. These findings suggest that characterizing the deficits in resting-state connectivity of top-down processes in stroke survivors may help optimize cognitive and physical rehabilitation therapies by individually targeting specific neural pathway. PMID:21839174

  18. Effective Connectivity Reveals Right-Hemisphere Dominance in Audiospatial Perception: Implications for Models of Spatial Neglect

    Science.gov (United States)

    Friston, Karl J.; Mattingley, Jason B.; Roepstorff, Andreas; Garrido, Marta I.

    2014-01-01

    Detecting the location of salient sounds in the environment rests on the brain's ability to use differences in sounds arriving at both ears. Functional neuroimaging studies in humans indicate that the left and right auditory hemispaces are coded asymmetrically, with a rightward attentional bias that reflects spatial attention in vision. Neuropsychological observations in patients with spatial neglect have led to the formulation of two competing models: the orientation bias and right-hemisphere dominance models. The orientation bias model posits a symmetrical mapping between one side of the sensorium and the contralateral hemisphere, with mutual inhibition of the ipsilateral hemisphere. The right-hemisphere dominance model introduces a functional asymmetry in the brain's coding of space: the left hemisphere represents the right side, whereas the right hemisphere represents both sides of the sensorium. We used Dynamic Causal Modeling of effective connectivity and Bayesian model comparison to adjudicate between these alternative network architectures, based on human electroencephalographic data acquired during an auditory location oddball paradigm. Our results support a hemispheric asymmetry in a frontoparietal network that conforms to the right-hemisphere dominance model. We show that, within this frontoparietal network, forward connectivity increases selectively in the hemisphere contralateral to the side of sensory stimulation. We interpret this finding in light of hierarchical predictive coding as a selective increase in attentional gain, which is mediated by feedforward connections that carry precision-weighted prediction errors during perceptual inference. This finding supports the disconnection hypothesis of unilateral neglect and has implications for theories of its etiology. PMID:24695717

  19. Aging Effects on Whole-Brain Functional Connectivity in Adults Free of Cognitive and Psychiatric Disorders.

    Science.gov (United States)

    Ferreira, Luiz Kobuti; Regina, Ana Carolina Brocanello; Kovacevic, Natasa; Martin, Maria da Graça Morais; Santos, Pedro Paim; Carneiro, Camila de Godoi; Kerr, Daniel Shikanai; Amaro, Edson; McIntosh, Anthony Randal; Busatto, Geraldo F

    2016-09-01

    Aging is associated with decreased resting-state functional connectivity (RSFC) within the default mode network (DMN), but most functional imaging studies have restricted the analysis to specific brain regions or networks, a strategy not appropriate to describe system-wide changes. Moreover, few investigations have employed operational psychiatric interviewing procedures to select participants; this is an important limitation since mental disorders are prevalent and underdiagnosed and can be associated with RSFC abnormalities. In this study, resting-state fMRI was acquired from 59 adults free of cognitive and psychiatric disorders according to standardized criteria and based on extensive neuropsychological and clinical assessments. We tested for associations between age and whole-brain RSFC using Partial Least Squares, a multivariate technique. We found that normal aging is not only characterized by decreased RSFC within the DMN but also by ubiquitous increases in internetwork positive correlations and focal internetwork losses of anticorrelations (involving mainly connections between the DMN and the attentional networks). Our results reinforce the notion that the aging brain undergoes a dedifferentiation processes with loss of functional diversity. These findings advance the characterization of healthy aging effects on RSFC and highlight the importance of adopting a broad, system-wide perspective to analyze brain connectivity. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Effect of Wells’ Connectivity Enhancement on the Performance of Vapor Extraction (VAPEX Process

    Directory of Open Access Journals (Sweden)

    Mohammadpoor Mehdi

    2016-03-01

    Full Text Available Drawbacks of the thermal recovery techniques such as excessive heat loss to the surrounding formations and carbon dioxide emissions during these processes have directed the interests of researchers towards more viable alternatives such as solvent-based recovery techniques (e.g. VAPEX. One of the key parameters to implement a successful VAPEX process is to control the profiles of vapour chamber and consequently improve the areal sweep efficiency. In this regard, an optimum well configuration and well connectivity establishment between the injection and production wells are desirable. The main focus of this research is to extensively conduct series of experiments to investigate the effect of injection/production wells connectivity on the performance of VAPEX process. For this purpose, two large-scale physical models were employed. Propane and propane/carbon dioxide mixtures were selected as the injection solvents in the visual sand-packed physical models saturated with heavy oil sample from Saskatchewan (Canada heavy oil. Various injection/production scenarios were followed and it was found that the initial connection path between the injector and producer had a significant impact on the vapour chamber profiles and consequently on the ultimate recovery performance of the VAPEX process.

  1. Anisotropy of the monomer random walk in a polymer melt: local-order and connectivity effects

    International Nuclear Information System (INIS)

    Bernini, S; Leporini, D

    2016-01-01

    The random walk of a bonded monomer in a polymer melt is anisotropic due to local order and bond connectivity. We investigate both effects by molecular-dynamics simulations on melts of fully-flexible linear chains ranging from dimers (M  =  2) up to entangled polymers (M  =  200). The corresponding atomic liquid is also considered a reference system. To disentangle the influence of the local geometry and the bond arrangements, and to reveal their interplay, we define suitable measures of the anisotropy emphasising either the former or the latter aspect. Connectivity anisotropy, as measured by the correlation between the initial bond orientation and the direction of the subsequent monomer displacement, shows a slight enhancement due to the local order at times shorter than the structural relaxation time. At intermediate times—when the monomer displacement is comparable to the bond length—a pronounced peak and then decays slowly as t −1/2 , becoming negligible when the displacement is as large as about five bond lengths, i.e. about four monomer diameters or three Kuhn lengths. Local-geometry anisotropy, as measured by the correlation between the initial orientation of a characteristic axis of the Voronoi cell and the subsequent monomer dynamics, is affected at shorter times than the structural relaxation time by the cage shape with antagonistic disturbance by the connectivity. Differently, at longer times, the connectivity favours the persistence of the local-geometry anisotropy, which vanishes when the monomer displacement exceeds the bond length. Our results strongly suggest that the sole consideration of the local order is not enough to understand the microscopic origin of the rattling amplitude of the trapped monomer in the cage of the neighbours. (paper)

  2. A realistic neural mass model of the cortex with laminar-specific connections and synaptic plasticity - evaluation with auditory habituation.

    Directory of Open Access Journals (Sweden)

    Peng Wang

    Full Text Available In this work we propose a biologically realistic local cortical circuit model (LCCM, based on neural masses, that incorporates important aspects of the functional organization of the brain that have not been covered by previous models: (1 activity dependent plasticity of excitatory synaptic couplings via depleting and recycling of neurotransmitters and (2 realistic inter-laminar dynamics via laminar-specific distribution of and connections between neural populations. The potential of the LCCM was demonstrated by accounting for the process of auditory habituation. The model parameters were specified using Bayesian inference. It was found that: (1 besides the major serial excitatory information pathway (layer 4 to layer 2/3 to layer 5/6, there exists a parallel "short-cut" pathway (layer 4 to layer 5/6, (2 the excitatory signal flow from the pyramidal cells to the inhibitory interneurons seems to be more intra-laminar while, in contrast, the inhibitory signal flow from inhibitory interneurons to the pyramidal cells seems to be both intra- and inter-laminar, and (3 the habituation rates of the connections are unsymmetrical: forward connections (from layer 4 to layer 2/3 are more strongly habituated than backward connections (from Layer 5/6 to layer 4. Our evaluation demonstrates that the novel features of the LCCM are of crucial importance for mechanistic explanations of brain function. The incorporation of these features into a mass model makes them applicable to modeling based on macroscopic data (like EEG or MEG, which are usually available in human experiments. Our LCCM is therefore a valuable building block for future realistic models of human cognitive function.

  3. Evaluation of a countermeasure against wake galloping using wire connection method; Wake galloping ni taisuru seishin wire no yukosei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, T.; Mukai, H.; Sano, N. [Kajima Corp., Tokyo (Japan)

    1994-10-31

    A plurality of parallel cables have been recently employed for long-span cable-stayed bridges. Use of such parallel cables thereupon leads to a special type of wind-induced vibration called wake galloping (simply referred to as WG.) owing to air turbulence caused by upstream cables. This paper attempts to evaluate measures against the WG using a wire connecting method, and identifies the most important influencing factor and the validity of the measures through wind tunnel tests. The following results are hereby clarified. Even if the deformation rigidity of the cables is increased, it is impossible to raise the wind velocity of the WG. The wind velocity of the WG can not be reduced from a wind tunnel wind velocity using non-dimensional wind velocity. The wire connecting method proves to be more effective for reducing the amplitude of the vibration. Provided cables are coupled into a multi-stage using the wire connection method, overall vibration with a greater amplitude can be restricted. To the factor of the restriction additional deformation rigidity of the cables more contributes compared with additional weight of the cables. 9 refs., 13 figs., 2 tabs.

  4. Are Subjective Evaluations Biased by Social Factors or Connections? An Econometric Analysis of Soccer Referee Decisions

    OpenAIRE

    Scoppa, Vincenzo

    2008-01-01

    Many incentive contracts are based on subjective evaluations and contractual disputes depend on judges’ decisions. However, subjective evaluations raise risks of favouritism and distortions. Sport contests are a fruitful field for testing empirically theories of incentives. In this paper the behaviour of the referees in the Italian soccer (football) league (“Serie A”) is analyzed. Using data on injury (or extra) time subjectively assigned by the referee at the end of the match and controlling...

  5. Altered structural and effective connectivity in anorexia and bulimia nervosa in circuits that regulate energy and reward homeostasis.

    Science.gov (United States)

    Frank, G K W; Shott, M E; Riederer, J; Pryor, T L

    2016-11-01

    Anorexia and bulimia nervosa are severe eating disorders that share many behaviors. Structural and functional brain circuits could provide biological links that those disorders have in common. We recruited 77 young adult women, 26 healthy controls, 26 women with anorexia and 25 women with bulimia nervosa. Probabilistic tractography was used to map white matter connectivity strength across taste and food intake regulating brain circuits. An independent multisample greedy equivalence search algorithm tested effective connectivity between those regions during sucrose tasting. Anorexia and bulimia nervosa had greater structural connectivity in pathways between insula, orbitofrontal cortex and ventral striatum, but lower connectivity from orbitofrontal cortex and amygdala to the hypothalamus (Pbulimia nervosa effective connectivity was directed from anterior cingulate via ventral striatum to the hypothalamus. Across all groups, sweetness perception was predicted by connectivity strength in pathways connecting to the middle orbitofrontal cortex. This study provides evidence that white matter structural as well as effective connectivity within the energy-homeostasis and food reward-regulating circuitry is fundamentally different in anorexia and bulimia nervosa compared with that in controls. In eating disorders, anterior cingulate cognitive-emotional top down control could affect food reward and eating drive, override hypothalamic inputs to the ventral striatum and enable prolonged food restriction.

  6. The effect of epoch length on estimated EEG functional connectivity and brain network organisation

    Science.gov (United States)

    Fraschini, Matteo; Demuru, Matteo; Crobe, Alessandra; Marrosu, Francesco; Stam, Cornelis J.; Hillebrand, Arjan

    2016-06-01

    Objective. Graph theory and network science tools have revealed fundamental mechanisms of functional brain organization in resting-state M/EEG analysis. Nevertheless, it is still not clearly understood how several methodological aspects may bias the topology of the reconstructed functional networks. In this context, the literature shows inconsistency in the chosen length of the selected epochs, impeding a meaningful comparison between results from different studies. Approach. The aim of this study was to provide a network approach insensitive to the effects that epoch length has on functional connectivity and network reconstruction. Two different measures, the phase lag index (PLI) and the amplitude envelope correlation (AEC) were applied to EEG resting-state recordings for a group of 18 healthy volunteers using non-overlapping epochs with variable length (1, 2, 4, 6, 8, 10, 12, 14 and 16 s). Weighted clustering coefficient (CCw), weighted characteristic path length (L w) and minimum spanning tree (MST) parameters were computed to evaluate the network topology. The analysis was performed on both scalp and source-space data. Main results. Results from scalp analysis show a decrease in both mean PLI and AEC values with an increase in epoch length, with a tendency to stabilize at a length of 12 s for PLI and 6 s for AEC. Moreover, CCw and L w show very similar behaviour, with metrics based on AEC more reliable in terms of stability. In general, MST parameters stabilize at short epoch lengths, particularly for MSTs based on PLI (1-6 s versus 4-8 s for AEC). At the source-level the results were even more reliable, with stability already at 1 s duration for PLI-based MSTs. Significance. The present work suggests that both PLI and AEC depend on epoch length and that this has an impact on the reconstructed network topology, particularly at the scalp-level. Source-level MST topology is less sensitive to differences in epoch length, therefore enabling the comparison of brain

  7. Effective connectivity and gamma oscillations in a group at risk of psychosis

    DEFF Research Database (Denmark)

    Larsen, Kit Melissa

    .2 deletion carriers and healthy controls. Both conventional analysis of the MMN responses as well as a more sophisticated approach by means of Dynamic Causal Modelling (DCM) were carried out. DCM is a technique to extract effective connectivity between pre-specified bran areas. With this technique we...... by employing a parametric DCM to study the underlying network of repetition suppression in 22q11.2 deletion carriers and healthy controls. While results for the control group indicated a processing in accordance with the predictive coding theory, this was not the case for the 22q11.2 deletion carriers. Finally...

  8. Quantum mechanics of relativistic particles in multiply connected spaces and the Aharonov-Bohm effect

    International Nuclear Information System (INIS)

    Gamboa, J.; Rivelles, V.O.

    1990-04-01

    We consider the motion of free relativistic particles in multiply connected spaces. We show that if one of the spatial dimensions has the topology of a circle then the D dimensional spacetime is compactified to D-1 dimensions and the particle mass increases by an amount which is proportional to a quantum phase factor and inversely proportional to the radius of the circle. We also consider the relativistic Aharonov-Bohm effect and we show that the interference pattern is a universal characteristic due only to the topological properties of the experimental situation and not to the intrinsic properties of the particle. The propagators are calculated in both situations. (author) [pt

  9. Techno-Economic Performance Evaluation for Olive Mills Powered by Grid-Connected Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Ovidio Rabaza

    2015-10-01

    Full Text Available In recent years, due to the rise in petroleum prices and greenhouse gas emissions, renewable energy has been recommended as a power source for different types of facilities. For the period 2010 to 2020 the European Commission has established three key objectives related to climatic change and energy sustainability, such as reductions of CO2 emissions, increases in the use of renewable energy, and improvements in energy efficiency. A key industry is olive oil production in olive mills, where there is a great opportunity to reduce electricity consumption, increase additional profits related to the reduction of technologies that are harmful to the environment, and to cut back maintenance costs. For this reason, a feasibility study of grid-connected photovoltaics (PV systems has been carried out for different types of olive mills in Andalusia (southern Spain. This region is highly energy dependent, but has an abundance of “green” resources to be exploited. The results of this study contemplate a reduction in spending on electrical power of between 2% and 37%, and an increase in the use of renewable energy of between 2% and 26%. These results are according to the self-consumption or net metering policy and the production capacity of olive oil.

  10. Effective connectivity within the frontoparietal control network differentiates cognitive control and working memory.

    Science.gov (United States)

    Harding, Ian H; Yücel, Murat; Harrison, Ben J; Pantelis, Christos; Breakspear, Michael

    2015-02-01

    Cognitive control and working memory rely upon a common fronto-parietal network that includes the inferior frontal junction (IFJ), dorsolateral prefrontal cortex (dlPFC), pre-supplementary motor area/dorsal anterior cingulate cortex (pSMA/dACC), and intraparietal sulcus (IPS). This network is able to flexibly adapt its function in response to changing behavioral goals, mediating a wide range of cognitive demands. Here we apply dynamic causal modeling to functional magnetic resonance imaging data to characterize task-related alterations in the strength of network interactions across distinct cognitive processes. Evidence in favor of task-related connectivity dynamics was accrued across a very large space of possible network structures. Cognitive control and working memory demands were manipulated using a factorial combination of the multi-source interference task and a verbal 2-back working memory task, respectively. Both were found to alter the sensitivity of the IFJ to perceptual information, and to increase IFJ-to-pSMA/dACC connectivity. In contrast, increased connectivity from the pSMA/dACC to the IPS, as well as from the dlPFC to the IFJ, was uniquely driven by cognitive control demands; a task-induced negative influence of the dlPFC on the pSMA/dACC was specific to working memory demands. These results reflect a system of both shared and unique context-dependent dynamics within the fronto-parietal network. Mechanisms supporting cognitive engagement, response selection, and action evaluation may be shared across cognitive domains, while dynamic updating of task and context representations within this network are potentially specific to changing demands on cognitive control. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Using Hydraulic Modeling to Evaluate Lateral Connectivity Improvements under Alternative Restoration Scenarios in the Atchafalaya River Basin

    Science.gov (United States)

    Hayden-Lesmeister, A.; Remo, J. W.; Piazza, B.

    2017-12-01

    The Atchafalaya River (AR) in Louisiana is the principal distributary of the Mississippi River. Reach to system scale modifications on the AR and throughout its basin for regional flood mitigation, navigation, and hydrocarbon extraction have substantially altered the hydrologic connectivity between the river and its floodplain wetlands, threatening the ecological integrity of this globally-important ecosystem. Stakeholder groups agree that restoring flow connectivity is essential to maintaining the basin's water quality, and recent management efforts have focused on the 174 km2 Flat Lake Water Management Unit (WMU). Several flow-connectivity enhancement projects have been proposed by the Atchafalaya Basin Program's Technical Advisory Group, but none have been constructed. We collaborated with The Nature Conservancy and other agencies to obtain existing datasets and develop a 1D2D hydraulic model to examine whether proposed restoration projects improved lateral surface-water connectivity in the Flat Lake WMU. To do this, we employed a range of physical parameters (inundation extent, water depths, and rates of WSEL reduction) as potential indicators of improved connectivity with restoration. We ran simulations to examine two scenarios - a baseline scenario (S1) to examine current conditions (no restoration projects), and a full-implementation scenario (S2), where all restoration projects that could be examined at the model resolution were implemented. Potential indicators of improved lateral connectivity indicated that proposed projects may play an important role in improving water quality in the Flat Lake WMU. At the end of the constant-discharge portion of the run, average depths between S1 and S2 remained unchanged; however, depths and water levels were consistently lower for S2 during a drawdown. Volumetrically, up to 4.4 million m3 less water was in the Flat Lake system when projects were implemented. The results indicate that projects introduce nutrient

  12. HERMES: towards an integrated toolbox to characterize functional and effective brain connectivity.

    Science.gov (United States)

    Niso, Guiomar; Bruña, Ricardo; Pereda, Ernesto; Gutiérrez, Ricardo; Bajo, Ricardo; Maestú, Fernando; del-Pozo, Francisco

    2013-10-01

    The analysis of the interdependence between time series has become an important field of research in the last years, mainly as a result of advances in the characterization of dynamical systems from the signals they produce, the introduction of concepts such as generalized and phase synchronization and the application of information theory to time series analysis. In neurophysiology, different analytical tools stemming from these concepts have added to the 'traditional' set of linear methods, which includes the cross-correlation and the coherency function in the time and frequency domain, respectively, or more elaborated tools such as Granger Causality.This increase in the number of approaches to tackle the existence of functional (FC) or effective connectivity (EC) between two (or among many) neural networks, along with the mathematical complexity of the corresponding time series analysis tools, makes it desirable to arrange them into a unified-easy-to-use software package. The goal is to allow neuroscientists, neurophysiologists and researchers from related fields to easily access and make use of these analysis methods from a single integrated toolbox.Here we present HERMES ( http://hermes.ctb.upm.es ), a toolbox for the Matlab® environment (The Mathworks, Inc), which is designed to study functional and effective brain connectivity from neurophysiological data such as multivariate EEG and/or MEG records. It includes also visualization tools and statistical methods to address the problem of multiple comparisons. We believe that this toolbox will be very helpful to all the researchers working in the emerging field of brain connectivity analysis.

  13. Effects of VRK2 (rs2312147 on white matter connectivity in patients with schizophrenia.

    Directory of Open Access Journals (Sweden)

    Hoyoung Sohn

    Full Text Available Recent genome-wide association studies of schizophrenia reported a novel risk variant, rs2312147 at vaccinia-related kinase 2 gene (VRK2, in multiple Asian and European samples. However, its effect on the brain structure in schizophrenia is little known. We analyzed the brain structure of 36 schizophrenia patients and 18 healthy subjects with regard to rs2312147 genotype groups. Brain magnetic resonance scans for gray matter (GM and white matter (WM analysis, and genotype analysis for VRK2 rs2312147, were conducted. The Positive and Negative Syndrome Scale and the Digit Symbol Test were assessed for schizophrenia patients. There was no significant difference in either GM volume or WM connectivity with regard to rs2312147 genotype in healthy subjects. In contrast, we found significant differences in the WM connectivity between rs2312147 CC and CT/TT genotype groups of schizophrenia patients. The related brain areas included the splenium of corpus callosum, the left occipital lobe WM, the internal capsule (left anterior limb and right retrolenticular part, the bilateral temporal lobe WM, the left fornix/stria terminalis, the left cingulate gyrus WM, and the left parietal lobe WM. Voxelwise correlation analysis revealed that the Digit Symbol Test scores (age corrected correlated with the fractional anisotropy in WM tracts that previously showed significant group differences between the CT/TT and CC genotypes in the rs2312147 CT/TT genotype group, while no significant correlation was found in the CC genotype group. Our data may provide evidence for the effect of VRK2 on WM connectivity in patients with schizophrenia.

  14. Immunogenicity of influenza H1N1 vaccination in mixed connective tissue disease: effect of disease and therapy

    Directory of Open Access Journals (Sweden)

    Renata Miossi

    2013-01-01

    Full Text Available OBJECTIVE: To assess the potential acute effects regarding the immunogenicity and safety of non-adjuvanted influenza A H1N1/2009 vaccine in patients with mixed connective tissue disease and healthy controls. METHODS: Sixty-nine mixed connective tissue disease patients that were confirmed by Kasukawa's classification criteria and 69 age- and gender-matched controls participated in the study; the participants were vaccinated with the non-adjuvanted influenza A/California/7/2009 (H1N1 virus-like strain. The percentages of seroprotec-tion, seroconversion, geometric mean titer and factor increase in the geometric mean titer were calculated. The patients were clinically evaluated, and blood samples were collected pre- and 21 days post-vaccination to evaluate C-reactive protein, muscle enzymes and autoantibodies. Anti-H1N1 titers were determined using an influenza hemagglutination inhibition assay. ClinicalTrials.gov: NCT01151644. RESULTS: Before vaccination, no difference was observed regarding the seroprotection rates (p = 1.0 and geometric mean titer (p = 0.83 between the patients and controls. After vaccination, seroprotection (75.4% vs. 71%, (p = 0.7, seroconversion (68.1% vs. 65.2%, (p = 1.00 and factor increase in the geometric mean titer (10.0 vs. 8.0, p = 0.40 were similar in the two groups. Further evaluation of seroconversion in patients with and without current or previous history of muscle disease (p = 0.20, skin ulcers (p = 0.48, lupus-like cutaneous disease (p = 0.74, secondary Sjogren syndrome (p = 0.78, scleroderma-pattern in the nailfold capillaroscopy (p = 1.0, lymphopenia #1000/mm³ on two or more occasions (p = 1.0, hypergammaglobulinemia $1.6 g/d (p = 0.60, pulmonary hypertension (p = 1.0 and pulmonary fibrosis (p = 0.80 revealed comparable rates. Seroconversion rates were also similar in patients with and without immunosuppressants. Disease parameters, such as C-reactive protein (p = 0.94, aldolase (p = 0.73, creatine

  15. Lagrangian Flow Network: a new tool to evaluate connectivity and understand the structural complexity of marine populations

    Science.gov (United States)

    Rossi, V.; Dubois, M.; Ser-Giacomi, E.; Monroy, P.; Lopez, C.; Hernandez-Garcia, E.

    2016-02-01

    Assessing the spatial structure and dynamics of marine populations is still a major challenge for ecologists. The necessity to manage marine resources from a large-scale perspective and considering the whole ecosystem is now recognized but the absence of appropriate tools to address these objectives limits the implementation of globally pertinent conservation planning. Inspired from Network Theory, we present a new methodological framework called Lagrangian Flow Network which allows a systematic characterization of multi-scale dispersal and connectivity of early life history stages of marine organisms. The network is constructed by subdividing the basin into an ensemble of equal-area subregions which are interconnected through the transport of propagules by ocean currents. The present version allows the identification of hydrodynamical provinces and the computation of various connectivity proxies measuring retention and exchange of larvae. Due to our spatial discretization and subsequent network representation, as well as our Lagrangian approach, further methodological improvements are handily accessible. These future developments include a parametrization of habitat patchiness, the implementation of realistic larval traits and the consideration of abiotic variables (e.g. temperature, salinity, planktonic resources...) and their effects on larval production and survival. While the model is potentially tunable to any species whose biological traits and ecological preferences are precisely known, it can also be used in a more generic configuration by efficient computing and analysis of a large number of experiments with relevant ecological parameters. It permits a better characterization of population connectivity at multiple scales and it informs its ecological and managerial interpretations.

  16. Sustainable RC Beam-Column Connections with Headed Bars: A Formula for Shear Strength Evaluation

    Directory of Open Access Journals (Sweden)

    Minh-Tung Tran

    2018-02-01

    Full Text Available Beam-column joints are critical regions for reinforced concrete (RC frames subjected to earthquakes. The steel reinforcement is, in general, highly concentrated in these zones. This is why in many cases, headed bars are used. A headed bar is a longitudinal steel reinforcement whose end has a special button added to reduce the bonding length of the steel rebar. This paper establishes a formula predicting the shear strength of exterior RC beam-column connections where the beam longitudinal reinforcements use headed bars. A database was collected, which contained 30 experimental data about the exterior beam-column joints using headed bars and subjected to quasi-static cyclic loading. First, from the collected database, a statistical study was carried out to identify the most influencing parameters on the shear strength of the beam-column joints tested. The three most important parameters were identified and an empirical modified formula was developed based on the formula existing in the standards. The study showed that the results obtained from the modified formula proposed in the present study were closer to the experimental results than that obtained from the formula existing in the standards. Finally, a numerical study was performed on two T-form RC structures and the numerical results were compared with the prediction calculated from the modified formula proposed. For two investigated cases, the proposed formula provided the results in the safety side and the differences with the numerical results were less than 20%. Thus, the proposed formula can be used for a rapid assessment of the shear strength of RC joints using headed bars.

  17. FMRI connectivity analysis of acupuncture effects on an amygdala-associated brain network

    Directory of Open Access Journals (Sweden)

    Zhao Baixiao

    2008-11-01

    Full Text Available Abstract Background Recently, increasing evidence has indicated that the primary acupuncture effects are mediated by the central nervous system. However, specific brain networks underpinning these effects remain unclear. Results In the present study using fMRI, we employed a within-condition interregional covariance analysis method to investigate functional connectivity of brain networks involved in acupuncture. The fMRI experiment was performed before, during and after acupuncture manipulations on healthy volunteers at an acupuncture point, which was previously implicated in a neural pathway for pain modulation. We first identified significant fMRI signal changes during acupuncture stimulation in the left amygdala, which was subsequently selected as a functional reference for connectivity analyses. Our results have demonstrated that there is a brain network associated with the amygdala during a resting condition. This network encompasses the brain structures that are implicated in both pain sensation and pain modulation. We also found that such a pain-related network could be modulated by both verum acupuncture and sham acupuncture. Furthermore, compared with a sham acupuncture, the verum acupuncture induced a higher level of correlations among the amygdala-associated network. Conclusion Our findings indicate that acupuncture may change this amygdala-specific brain network into a functional state that underlies pain perception and pain modulation.

  18. Functional Activation and Effective Connectivity Differences in Adolescent Marijuana Users Performing a Simulated Gambling Task

    Directory of Open Access Journals (Sweden)

    Ashley Acheson

    2015-01-01

    Full Text Available Background. Adolescent marijuana use is associated with structural and functional differences in forebrain regions while performing memory and attention tasks. In the present study, we investigated neural processing in adolescent marijuana users experiencing rewards and losses. Fourteen adolescents with frequent marijuana use (>5 uses per week and 14 nonuser controls performed a computer task where they were required to guess the outcome of a simulated coin flip while undergoing magnetic resonance imaging. Results. Across all participants, “Wins” and “Losses” were associated with activations including cingulate, middle frontal, superior frontal, and inferior frontal gyri and declive activations. Relative to controls, users had greater activity in the middle and inferior frontal gyri, caudate, and claustrum during “Wins” and greater activity in the anterior and posterior cingulate, middle frontal gyrus, insula, claustrum, and declive during “Losses.” Effective connectivity analyses revealed similar overall network interactions among these regions for users and controls during both “Wins” and “Losses.” However, users and controls had significantly different causal interactions for 10 out of 28 individual paths during the “Losses” condition. Conclusions. Collectively, these results indicate adolescent marijuana users have enhanced neural responses to simulated monetary rewards and losses and relatively subtle differences in effective connectivity.

  19. A pooling-LiNGAM algorithm for effective connectivity analysis of fMRI data

    Directory of Open Access Journals (Sweden)

    Lele eXu

    2014-10-01

    Full Text Available The Independent Component Analysis - linear non-Gaussian acyclic model (LiNGAM, an algorithm that can be used to estimate the causal relationship among non-Gaussian distributed data, has the potential value to detect the effective connectivity of human brain areas. Under the assumptions that (a: the data generating process is linear, (b there are no unobserved confounders, and (c data have non-Gaussian distributions, LiNGAM can be used to discover the complete causal structure of data. Previous studies reveal that the algorithm could perform well when the data points being analyzed is relatively long. However, there are too few data points in most neuroimaging recordings, especially functional magnetic resonance imaging (fMRI, to allow the algorithm to converge. Smith’s study speculates a method by pooling data points across subjects may be useful to address this issue (Smith et al., 2011. Thus this study focus on validating Smith’s proposal of pooling data points across subjects for the use of LiNGAM, and this method is named as pooling-LiNGAM (pLiNGAM. Using both simulated and real fMRI data, our current study demonstrates the feasibility and efficiency of the pLiNGAM on the effective connectivity estimation.

  20. Effective connectivity between superior temporal gyrus and Heschl's gyrus during white noise listening: linear versus non-linear models.

    Science.gov (United States)

    Hamid, Ka; Yusoff, An; Rahman, Mza; Mohamad, M; Hamid, Aia

    2012-04-01

    This fMRI study is about modelling the effective connectivity between Heschl's gyrus (HG) and the superior temporal gyrus (STG) in human primary auditory cortices. MATERIALS #ENTITYSTARTX00026; Ten healthy male participants were required to listen to white noise stimuli during functional magnetic resonance imaging (fMRI) scans. Statistical parametric mapping (SPM) was used to generate individual and group brain activation maps. For input region determination, two intrinsic connectivity models comprising bilateral HG and STG were constructed using dynamic causal modelling (DCM). The models were estimated and inferred using DCM while Bayesian Model Selection (BMS) for group studies was used for model comparison and selection. Based on the winning model, six linear and six non-linear causal models were derived and were again estimated, inferred, and compared to obtain a model that best represents the effective connectivity between HG and the STG, balancing accuracy and complexity. Group results indicated significant asymmetrical activation (p(uncorr) Model comparison results showed strong evidence of STG as the input centre. The winning model is preferred by 6 out of 10 participants. The results were supported by BMS results for group studies with the expected posterior probability, r = 0.7830 and exceedance probability, ϕ = 0.9823. One-sample t-tests performed on connection values obtained from the winning model indicated that the valid connections for the winning model are the unidirectional parallel connections from STG to bilateral HG (p model comparison between linear and non-linear models using BMS prefers non-linear connection (r = 0.9160, ϕ = 1.000) from which the connectivity between STG and the ipsi- and contralateral HG is gated by the activity in STG itself. We are able to demonstrate that the effective connectivity between HG and STG while listening to white noise for the respective participants can be explained by a non-linear dynamic causal model with

  1. Lifetime Evaluation of Grid-Connected PV Inverters Considering Panel Degradation Rates and Installation Sites

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

    2018-01-01

    Lifetime of PV inverters is affected by the installation sites related to different solar irradiance and ambient temperature profiles (also referred to as mission profiles). In fact, the installation site also affects the degradation rate of the PV panels, and thus long-term energy production...... and reliability. Prior-art lifetime analysis in PV inverters has not yet investigated the impact of PV panel degradations. This paper thus evaluates the lifetime of PV inverters considering panel degradation rates and mission profiles. Evaluations have been carried out on PV systems installed in Denmark...... and Arizona. The results reveal that the PV panel degradation rate has a considerable impact on the PV inverter lifetime, especially in the hot climate (e.g., Arizona), where the panel degrades at a faster rate. In that case, the PV inverter lifetime prediction can be deviated by 54%, if the impact of PV...

  2. Lifetime Evaluation of Grid-Connected PV Inverters Considering Panel Degradation Rates and Installation Sites

    OpenAIRE

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso; Blaabjerg, Frede

    2018-01-01

    Lifetime of PV inverters is affected by the installation sites related to different solar irradiance and ambient temperature profiles (also referred to as mission profiles). In fact, the installation site also affects the degradation rate of the PV panels, and thus long-term energy production and reliability. Prior-art lifetime analysis in PV inverters has not yet investigated the impact of PV panel degradations. This paper thus evaluates the lifetime of PV inverters considering panel degrada...

  3. Rapid Evaluation of Power Degradation in Series Connection of Single Feeding Microsized Microbial Fuel Cells

    KAUST Repository

    Rojas, Jhonathan Prieto; Alqarni, Wejdan Mohammed Mofleh; Hussain, Muhammad Mustafa

    2014-01-01

    We have developed a sustainable, single feeding, microsized, air-cathode and membrane-free microbial fuel cells with a volume of 40 mu L each, which we have used for rapid evaluation of power generation and viability of a series array of three cells seeking higher voltage levels. Contrary to expectations, the achieved power density was modest (45 mWm(-3)), limited due to non-uniformities in assembly and the single-channel feeding system.

  4. Rapid Evaluation of Power Degradation in Series Connection of Single Feeding Microsized Microbial Fuel Cells

    KAUST Repository

    Rojas, Jhonathan Prieto

    2014-07-08

    We have developed a sustainable, single feeding, microsized, air-cathode and membrane-free microbial fuel cells with a volume of 40 mu L each, which we have used for rapid evaluation of power generation and viability of a series array of three cells seeking higher voltage levels. Contrary to expectations, the achieved power density was modest (45 mWm(-3)), limited due to non-uniformities in assembly and the single-channel feeding system.

  5. Altered auditory processing and effective connectivity in 22q11.2 deletion syndrome.

    Science.gov (United States)

    Larsen, Kit Melissa; Mørup, Morten; Birknow, Michelle Rosgaard; Fischer, Elvira; Hulme, Oliver; Vangkilde, Anders; Schmock, Henriette; Baaré, William Frans Christiaan; Didriksen, Michael; Olsen, Line; Werge, Thomas; Siebner, Hartwig R; Garrido, Marta I

    2018-01-30

    22q11.2 deletion syndrome (22q11.2DS) is one of the most common copy number variants and confers a markedly increased risk for schizophrenia. As such, 22q11.2DS is a homogeneous genetic liability model which enables studies to delineate functional abnormalities that may precede disease onset. Mismatch negativity (MMN), a brain marker of change detection, is reduced in people with schizophrenia compared to healthy controls. Using dynamic causal modelling (DCM), previous studies showed that top-down effective connectivity linking the frontal and temporal cortex is reduced in schizophrenia relative to healthy controls in MMN tasks. In the search for early risk-markers for schizophrenia we investigated the neural basis of change detection in a group with 22q11.2DS. We recorded high-density EEG from 19 young non-psychotic 22q11.2 deletion carriers, as well as from 27 healthy non-carriers with comparable age distribution and sex ratio, while they listened to a sequence of sounds arranged in a roving oddball paradigm. Despite finding no significant reduction in the MMN responses, whole-scalp spatiotemporal analysis of responses to the tones revealed a greater fronto-temporal N1 component in the 22q11.2 deletion carriers. DCM showed reduced intrinsic connection within right primary auditory cortex as well as in the top-down, connection from the right inferior frontal gyrus to right superior temporal gyrus for 22q11.2 deletion carriers although not surviving correction for multiple comparison. We discuss these findings in terms of reduced adaptation and a general increased sensitivity to tones in 22q11.2DS. Copyright © 2018. Published by Elsevier B.V.

  6. Preparing for Evaluation: Lessons from the Evaluability Assessment of the Teagle Foundation's College-Community Connections Initiative. Report

    Science.gov (United States)

    Black, Kristin

    2016-01-01

    Funders, policymakers, and program leaders recognize the value of high-quality evidence. To make good use of a program evaluation, initiatives must contend with a set of fundamental questions first. Some of these are about the initiative itself: What outcomes does it seek to affect? Are daily activities in line with long-term goals? Others are…

  7. The Potential Connectivity of Waterhole Networks and the Effectiveness of a Protected Area under Various Drought Scenarios

    Science.gov (United States)

    O’Farrill, Georgina; Gauthier Schampaert, Kim; Rayfield, Bronwyn; Bodin, Örjan; Calmé, Sophie; Sengupta, Raja; Gonzalez, Andrew

    2014-01-01

    Landscape connectivity is considered a priority for ecosystem conservation because it may mitigate the synergistic effects of climate change and habitat loss. Climate change predictions suggest changes in precipitation regimes, which will affect the availability of water resources, with potential consequences for landscape connectivity. The Greater Calakmul Region of the Yucatan Peninsula (Mexico) has experienced a 16% decrease in precipitation over the last 50 years, which we hypothesise has affected water resource connectivity. We used a network model of connectivity, for three large endangered species (Baird’s tapir, white-lipped peccary and jaguar), to assess the effect of drought on waterhole availability and connectivity in a forested landscape inside and adjacent to the Calakmul Biosphere Reserve. We used reported travel distances and home ranges for our species to establish movement distances in our model. Specifically, we compared the effects of 10 drought scenarios on the number of waterholes (nodes) and the subsequent changes in network structure and node importance. Our analysis revealed that drought dramatically influenced spatial structure and potential connectivity of the network. Our results show that waterhole connectivity and suitable habitat (area surrounding waterholes) is lost faster inside than outside the reserve for all three study species, an outcome that may drive them outside the reserve boundaries. These results emphasize the need to assess how the variability in the availability of seasonal water resource may affect the viability of animal populations under current climate change inside and outside protected areas. PMID:24830392

  8. The potential connectivity of waterhole networks and the effectiveness of a protected area under various drought scenarios.

    Directory of Open Access Journals (Sweden)

    Georgina O'Farrill

    Full Text Available Landscape connectivity is considered a priority for ecosystem conservation because it may mitigate the synergistic effects of climate change and habitat loss. Climate change predictions suggest changes in precipitation regimes, which will affect the availability of water resources, with potential consequences for landscape connectivity. The Greater Calakmul Region of the Yucatan Peninsula (Mexico has experienced a 16% decrease in precipitation over the last 50 years, which we hypothesise has affected water resource connectivity. We used a network model of connectivity, for three large endangered species (Baird's tapir, white-lipped peccary and jaguar, to assess the effect of drought on waterhole availability and connectivity in a forested landscape inside and adjacent to the Calakmul Biosphere Reserve. We used reported travel distances and home ranges for our species to establish movement distances in our model. Specifically, we compared the effects of 10 drought scenarios on the number of waterholes (nodes and the subsequent changes in network structure and node importance. Our analysis revealed that drought dramatically influenced spatial structure and potential connectivity of the network. Our results show that waterhole connectivity and suitable habitat (area surrounding waterholes is lost faster inside than outside the reserve for all three study species, an outcome that may drive them outside the reserve boundaries. These results emphasize the need to assess how the variability in the availability of seasonal water resource may affect the viability of animal populations under current climate change inside and outside protected areas.

  9. Transient stability with grid connection and wind turbine drive-train effects

    DEFF Research Database (Denmark)

    Fajardo-R, Luis A.; Medina, Aurelio; Iov, Florin

    2009-01-01

    This paper assesses transient stability of grid-connected wind turbines, combining grid-connection, wind turbine flexibility, and induction generator stability features. Through a grid-connected 2 MW wind turbine cage-generator, the investigation is conducted to identify the critical clearing time...

  10. Decoding the different states of visual attention using functional and effective connectivity features in fMRI data.

    Science.gov (United States)

    Parhizi, Behdad; Daliri, Mohammad Reza; Behroozi, Mehdi

    2018-04-01

    The present paper concentrates on the impact of visual attention task on structure of the brain functional and effective connectivity networks using coherence and Granger causality methods. Since most studies used correlation method and resting-state functional connectivity, the task-based approach was selected for this experiment to boost our knowledge of spatial and feature-based attention. In the present study, the whole brain was divided into 82 sub-regions based on Brodmann areas. The coherence and Granger causality were applied to construct functional and effective connectivity matrices. These matrices were converted into graphs using a threshold, and the graph theory measures were calculated from it including degree and characteristic path length. Visual attention was found to reveal more information during the spatial-based task. The degree was higher while performing a spatial-based task, whereas characteristic path length was lower in the spatial-based task in both functional and effective connectivity. Primary and secondary visual cortex (17 and 18 Brodmann areas) were highly connected to parietal and prefrontal cortex while doing visual attention task. Whole brain connectivity was also calculated in both functional and effective connectivity. Our results reveal that Brodmann areas of 17, 18, 19, 46, 3 and 4 had a significant role proving that somatosensory, parietal and prefrontal regions along with visual cortex were highly connected to other parts of the cortex during the visual attention task. Characteristic path length results indicated an increase in functional connectivity and more functional integration in spatial-based attention compared with feature-based attention. The results of this work can provide useful information about the mechanism of visual attention at the network level.

  11. Effects of land use on lake nutrients: The importance of scale, hydrologic connectivity, and region

    Science.gov (United States)

    Soranno, Patricia A.; Cheruvelil, Kendra Spence; Wagner, Tyler; Webster, Katherine E.; Bremigan, Mary Tate

    2015-01-01

    Catchment land uses, particularly agriculture and urban uses, have long been recognized as major drivers of nutrient concentrations in surface waters. However, few simple models have been developed that relate the amount of catchment land use to downstream freshwater nutrients. Nor are existing models applicable to large numbers of freshwaters across broad spatial extents such as regions or continents. This research aims to increase model performance by exploring three factors that affect the relationship between land use and downstream nutrients in freshwater: the spatial extent for measuring land use, hydrologic connectivity, and the regional differences in both the amount of nutrients and effects of land use on them. We quantified the effects of these three factors that relate land use to lake total phosphorus (TP) and total nitrogen (TN) in 346 north temperate lakes in 7 regions in Michigan, USA. We used a linear mixed modeling framework to examine the importance of spatial extent, lake hydrologic class, and region on models with individual lake nutrients as the response variable, and individual land use types as the predictor variables. Our modeling approach was chosen to avoid problems of multi-collinearity among predictor variables and a lack of independence of lakes within regions, both of which are common problems in broad-scale analyses of freshwaters. We found that all three factors influence land use-lake nutrient relationships. The strongest evidence was for the effect of lake hydrologic connectivity, followed by region, and finally, the spatial extent of land use measurements. Incorporating these three factors into relatively simple models of land use effects on lake nutrients should help to improve predictions and understanding of land use-lake nutrient interactions at broad scales.

  12. FUNCTIONAL AND EFFECTIVE CONNECTIVITY OF VISUAL WORD RECOGNITION AND HOMOPHONE ORTHOGRAPHIC ERRORS.

    Directory of Open Access Journals (Sweden)

    JOAN eGUÀRDIA-OLMOS

    2015-05-01

    Full Text Available The study of orthographic errors in a transparent language like Spanish is an important topic in relation to writing acquisition. The development of neuroimaging techniques, particularly functional Magnetic Resonance Imaging (fMRI, has enabled the study of such relationships between brain areas. The main objective of the present study was to explore the patterns of effective connectivity by processing pseudohomophone orthographic errors among subjects with high and low spelling skills. Two groups of 12 Mexican subjects each, matched by age, were formed based on their results in a series of ad-hoc spelling-related out-scanner tests: a High Spelling Skills group (HSS and a Low Spelling Skills group (LSS. During the fMRI session, two experimental tasks were applied (spelling recognition task and visuoperceptual recognition task. Regions of Interest (ROIs and their signal values were obtained for both tasks. Based on these values, SEMs (Structural Equation Models were obtained for each group of spelling competence (HSS and LSS and task through ML (Maximum Likelihood estimation, and the model with the best fit was chosen in each case. Likewise, DCM (Dynamic Causal Models were estimated for all the conditions across tasks and groups. The HSS group’s SEM results suggest that, in the spelling recognition task, the right middle temporal gyrus, and, to a lesser extent, the left parahippocampal gyrus receive most of the significant effects, whereas the DCM results in the visuoperceptual recognition task show less complex effects, but still congruent with the previous results, with an important role in several areas. In general, these results are consistent with the major findings in partial studies about linguistic activities but they are the first analyses of statistical effective brain connectivity in transparent languages.

  13. Effect of tree thinning and skidding trails on hydrological connectivity in two Japanese forest catchments

    Science.gov (United States)

    López-Vicente, Manuel; Sun, Xinchao; Onda, Yuichi; Kato, Hiroaki; Gomi, Takashi; Hiraoka, Marino

    2017-09-01

    Land use composition and patterns influence the hydrological response in mountainous and forest catchments. In plantation forest, management operations (FMO) modify the spatial and temporal dynamics of overland flow processes. However, we found a gap in the literature focussed on modelling hydrological connectivity (HC) in plantation forest under different FMO. In this study, we simulated HC in two steep paired forest subcatchments (K2 and K3, 33.2 ha), composed of Japanese cypress (Chamaecyparis obtusa Endl.) and Japanese cedar (Cryptomeria japonica D. Don) plantations (59% of the total area) against a tree thinning intensity of 50% at different time. Additionally, construction of new skidding trails and vegetation recovery was simulated on five thinning-based scenarios that covered a 40-month test period (July 2010 - October 2013). As a future scenario, six check-dams located in the main streams were proposed to reduce sediment and radionuclide delivery. An updated version of Borselli's index of runoff and sediment connectivity was run, using the D-infinity flow accumulation algorithm and exploiting three 0.5-m resolution digital elevation models. On the basis of the pre-FMO scenario, HC increased at catchment scale owing to tree thinning and the new skidding trails. This change was more noticeable within the area affected by the FMO, where HC increased by 11.4% and 10.5% in the cypress and cedar plantations in K2 respectively and by 8.8% in the cedar plantation in K3. At hillslope plot and stream scales, the evolution in the values of HC was less evident, except the increment (by 5.4%) observed in the streams at K2 after the FMO. Progressive vegetation recovery after the FMO triggered a slight reduction of connectivity in all compartments of both subcatchments. Forest roads and especially skidding trails presented the highest values of HC, appearing as the most efficient features connecting the different vegetation patches with the stream network. The spatial

  14. Chimeras in leaky integrate-and-fire neural networks: effects of reflecting connectivities

    Science.gov (United States)

    Tsigkri-DeSmedt, Nefeli Dimitra; Hizanidis, Johanne; Schöll, Eckehard; Hövel, Philipp; Provata, Astero

    2017-07-01

    The effects of attracting-nonlocal and reflecting connectivity are investigated in coupled Leaky Integrate-and-Fire (LIF) elements, which model the exchange of electrical signals between neurons. Earlier investigations have demonstrated that repulsive-nonlocal and hierarchical network connectivity can induce complex synchronization patterns and chimera states in systems of coupled oscillators. In the LIF system we show that if the elements are nonlocally linked with positive diffusive coupling on a ring network, the system splits into a number of alternating domains. Half of these domains contain elements whose potential stays near the threshold and they are interrupted by active domains where the elements perform regular LIF oscillations. The active domains travel along the ring with constant velocity, depending on the system parameters. When we introduce reflecting coupling in LIF networks unexpected complex spatio-temporal structures arise. For relatively extensive ranges of parameter values, the system splits into two coexisting domains: one where all elements stay near the threshold and one where incoherent states develop, characterized by multi-leveled mean phase velocity profiles.

  15. Larval connectivity of pearl oyster through biophysical modelling; evidence of food limitation and broodstock effect

    Science.gov (United States)

    Thomas, Yoann; Dumas, Franck; Andréfouët, Serge

    2016-12-01

    The black-lip pearl oyster (Pinctada margaritifera) is cultured extensively to produce black pearls, especially in French Polynesia atoll lagoons. This aquaculture relies on spat collection, a process that experiences spatial and temporal variability and needs to be optimized by understanding which factors influence recruitment. Here, we investigate the sensitivity of P. margaritifera larval dispersal to both physical and biological factors in the lagoon of Ahe atoll. Coupling a validated 3D larval dispersal model, a bioenergetics larval growth model following the Dynamic Energy Budget (DEB) theory, and a population dynamics model, the variability of lagoon-scale connectivity patterns and recruitment potential is investigated. The relative contribution of reared and wild broodstock to the lagoon-scale recruitment potential is also investigated. Sensitivity analyses pointed out the major effect of the broodstock population structure as well as the sensitivity to larval mortality rate and inter-individual growth variability to larval supply and to the subsequent settlement potential. The application of the growth model clarifies how trophic conditions determine the larval supply and connectivity patterns. These results provide new cues to understand the dynamics of bottom-dwelling populations in atoll lagoons, their recruitment, and discuss how to take advantage of these findings and numerical models for pearl oyster management.

  16. Effective connectivity gateways to the Theory of Mind network in processing communicative intention.

    Science.gov (United States)

    Tettamanti, Marco; Vaghi, Matilde M; Bara, Bruno G; Cappa, Stefano F; Enrici, Ivan; Adenzato, Mauro

    2017-07-15

    An Intention Processing Network (IPN), involving the medial prefrontal cortex, precuneus, bilateral posterior superior temporal sulcus, and temporoparietal junctions, plays a fundamental role in comprehending intentions underlying action goals. In a previous fMRI study, we showed that, depending on the linguistic or extralinguistic (gestural) modality used to convey the intention, the IPN is complemented by activation of additional brain areas, reflecting distinct modality-specific input gateways to the IPN. These areas involve, for the linguistic modality, the left inferior frontal gyrus (LIFG), and for the extralinguistic modality, the right inferior frontal gyrus (RIFG). Here, we tested the modality-specific gateway hypothesis, by using DCM to measure inter-regional functional integration dynamics between the IPN and LIFG/RIFG gateways. We found strong evidence of a well-defined effective connectivity architecture mediating the functional integration between the IPN and the inferior frontal cortices. The connectivity dynamics indicate a modality-specific propagation of stimulus information from LIFG to IPN for the linguistic modality, and from RIFG to IPN for the extralinguistic modality. Thus, we suggest a functional model in which the modality-specific gateways mediate the structural and semantic decoding of the stimuli, and allow for the modality-specific communicative information to be integrated in Theory of Mind inferences elaborated through the IPN. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Spatial localization of the first and last enzymes effectively connects active metabolic pathways in bacteria.

    Science.gov (United States)

    Meyer, Pablo; Cecchi, Guillermo; Stolovitzky, Gustavo

    2014-12-14

    Although much is understood about the enzymatic cascades that underlie cellular biosynthesis, comparatively little is known about the rules that determine their cellular organization. We performed a detailed analysis of the localization of E.coli GFP-tagged enzymes for cells growing exponentially. We found that out of 857 globular enzymes, at least 219 have a discrete punctuate localization in the cytoplasm and catalyze the first or the last reaction in 60% of biosynthetic pathways. A graph-theoretic analysis of E.coli's metabolic network shows that localized enzymes, in contrast to non-localized ones, form a tree-like hierarchical structure, have a higher within-group connectivity, and are traversed by a higher number of feed-forward and feedback loops than their non-localized counterparts. A Gene Ontology analysis of these enzymes reveals an enrichment of terms related to essential metabolic functions in growing cells. Given that these findings suggest a distinct metabolic role for localization, we studied the dynamics of cellular localization of the cell wall synthesizing enzymes in B. subtilis and found that enzymes localize during exponential growth but not during stationary growth. We conclude that active biochemical pathways inside the cytoplasm are organized spatially following a rule where their first or their last enzymes localize to effectively connect the different active pathways and thus could reflect the activity state of the cell's metabolic network.

  18. Actual performance and characteristic of a grid connected photovoltaic power system in the tropics: A short term evaluation

    International Nuclear Information System (INIS)

    Khatib, Tamer; Sopian, Kamaruzzaman; Kazem, Hussein A.

    2013-01-01

    Highlights: • We analyzed an actual performance of grid connected PV system. • We derived accurate models for the system based on the actual performance. • We assist the electricity productively of the proposed system. - Abstract: This paper presents a field operation experience for a grid connected PV system under tropical climate. The system is consisted of a 5 kWp photovoltaic (PV) array and a 6 kW DC/AC inverter. The operation performance data are recorded in order to develop accurate mathematical models for the system as well as to evaluate the productivity of the system. The experiment results show that, the average PV performance (the ratio of the theoretical performance to the actual performance) is 73.12% while the average inverter performance (the ratio of the theoretical inverter efficiency to the actual inverter efficiency) is 98.56%. Moreover, it is found that the daily yield factor of the PV system is 2.51 kW h/kWp day while, the capacity factor is 10.47%. However, it is concluded that the productivity of the system is below the prospected rate and thus, an inspection of the system must be done in order to diagnose the problem of the system’s low productivity. This paper presents worthwhile information for those who are interested in PV system installation in Malaysia and nearby country

  19. Magnetic resonance imaging in the evaluation of patients with aseptic meningoencephalitis and connective tissue disorders

    Energy Technology Data Exchange (ETDEWEB)

    Appenzeller, Simone; Kobayashi, Eliane; Costallat, Lilian T.L.; Zanardi, Veronica de Araujo; Ribeiro Neto, Jose Menezes; Damasceno, Benito Pereira; Cendes, Fernando [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas

    2000-03-01

    To describe the role of magnetic resonance imaging (MRI) in the evaluation of patients with chronic and recurrent aseptic meningitis. Method: A retrospective study of five patients with aseptic meningoencefalitis diagnosed by clinical and CSF findings. CT scans showed without no relevant findings. Results: MRI showed small multifocal lesions hyperintense on T2 weight images and FLAIR, with mild or no gadolinium enhancement, mainly in periventricular and subcortical regions. Meningoencephalitis preceded the diagnosis of the underlying disease in four patients (Behcet's disease or systemic lupus erythematosus). After the introduction of adequate treatment for the rheumatic disease, they did not present further symptoms of aseptic meningoencephalitis. Conclusion: Aseptic meningoencephalitis can be an early presentation of an autoimmune disease. It is important to emphasize the role of MRI in the diagnosis and follow-up of these patients. (author)

  20. Magnetic resonance imaging in the evaluation of patients with aseptic meningoencephalitis and connective tissue disorders

    International Nuclear Information System (INIS)

    Appenzeller, Simone; Kobayashi, Eliane; Costallat, Lilian T.L.; Zanardi, Veronica de Araujo; Ribeiro Neto, Jose Menezes; Damasceno, Benito Pereira; Cendes, Fernando

    2000-01-01

    To describe the role of magnetic resonance imaging (MRI) in the evaluation of patients with chronic and recurrent aseptic meningitis. Method: A retrospective study of five patients with aseptic meningoencefalitis diagnosed by clinical and CSF findings. CT scans showed without no relevant findings. Results: MRI showed small multifocal lesions hyperintense on T2 weight images and FLAIR, with mild or no gadolinium enhancement, mainly in periventricular and subcortical regions. Meningoencephalitis preceded the diagnosis of the underlying disease in four patients (Behcet's disease or systemic lupus erythematosus). After the introduction of adequate treatment for the rheumatic disease, they did not present further symptoms of aseptic meningoencephalitis. Conclusion: Aseptic meningoencephalitis can be an early presentation of an autoimmune disease. It is important to emphasize the role of MRI in the diagnosis and follow-up of these patients. (author)

  1. Magnetic resonance imaging in the evaluation of patients with aseptic meningoencephalitis and connective tissue disorders

    Directory of Open Access Journals (Sweden)

    APPENZELLER SIMONE

    2000-01-01

    Full Text Available OBJECTIVE: To describe the role of magnetic resonance imaging (MRI in the evaluation of patients with chronic and recurrent aseptic meningitis.METHOD: A retrospective study of five patients with aseptic meningoencefalitis diagnosed by clinical and CSF findings. CT scans showed without no relevant findings. RESULTS: MRI showed small multifocal lesions hyperintense on T2 weighted images and FLAIR, with mild or no gadolinium enhancement, mainly in periventricular and subcortical regions. Meningoencephalitis preceded the diagnosis of the underlying disease in four patients (Behçet´s disease or systemic lupus erythematosus. After the introduction of adequate treatment for the rheumatic disease, they did not present further symptoms of aseptic meningoencephalitis. CONCLUSION: Aseptic meningoencephalitis can be an early presentation of an autoimmune disease. It is important to emphasize the role of MRI in the diagnosis and follow-up of these patients.

  2. Maximum generation power evaluation of variable frequency offshore wind farms when connected to a single power converter

    Energy Technology Data Exchange (ETDEWEB)

    Gomis-Bellmunt, Oriol; Sumper, Andreas [Centre d' Innovacio Tecnologica en Convertidors Estatics i Accionaments (CITCEA-UPC), Universitat Politecnica de Catalunya UPC, Av. Diagonal, 647, Pl. 2, 08028 Barcelona (Spain); IREC Catalonia Institute for Energy Research, Barcelona (Spain); Junyent-Ferre, Adria; Galceran-Arellano, Samuel [Centre d' Innovacio Tecnologica en Convertidors Estatics i Accionaments (CITCEA-UPC), Universitat Politecnica de Catalunya UPC, Av. Diagonal, 647, Pl. 2, 08028 Barcelona (Spain)

    2010-10-15

    The paper deals with the evaluation of power generated by variable and constant frequency offshore wind farms connected to a single large power converter. A methodology to analyze different wind speed scenarios and system electrical frequencies is presented and applied to a case study, where it is shown that the variable frequency wind farm concept (VF) with a single power converter obtains 92% of the total available power, obtained with individual power converters in each wind turbine (PC). The PC scheme needs multiple power converters implying drawbacks in terms of cost, maintenance and reliability. The VF scheme is also compared to a constant frequency scheme CF, and it is shown that a significant power increase of more than 20% can be obtained with VF. The case study considers a wind farm composed of four wind turbines based on synchronous generators. (author)

  3. Effect of Neutral Grounding Protection Methods for Compensated Wind/PV Grid-Connected Hybrid Power Systems

    Directory of Open Access Journals (Sweden)

    Nurettin Çetinkaya

    2017-01-01

    Full Text Available The effects of the wind/PV grid-connected system (GCS can be categorized as technical, environmental, and economic impacts. It has a vital impact for improving the voltage in the power systems; however, it has some negative effects such as interfacing and fault clearing. This paper discusses different grounding methods for fault protection of High-voltage (HV power systems. Influences of these grounding methods for various fault characteristics on wind/PV GCSs are discussed. Simulation models are implemented in the Alternative Transient Program (ATP version of the Electromagnetic Transient Program (EMTP. The models allow for different fault factors and grounding methods. Results are obtained to evaluate the impact of each grounding method on the 3-phase short-circuit fault (SCF, double-line-to-ground (DLG fault, and single-line-to-ground (SLG fault features. Solid, resistance, and Petersen coil grounding are compared for different faults on wind/PV GCSs. Transient overcurrent and overvoltage waveforms are used to describe the fault case. This paper is intended as a guide to engineers in selecting adequate grounding and ground fault protection schemes for HV, for evaluating existing wind/PV GCSs to minimize the damage of the system components from faults. This research presents the contribution of wind/PV generators and their comparison with the conventional system alone.

  4. Acquisition, Analyses and Interpretation of fMRI Data: A Study on the Effective Connectivity in Human Primary Auditory Cortices

    International Nuclear Information System (INIS)

    Ahmad Nazlim Yusoff; Mazlyfarina Mohamad; Khairiah Abdul Hamid

    2011-01-01

    A study on the effective connectivity characteristics in auditory cortices was conducted on five healthy Malay male subjects with the age of 20 to 40 years old using functional magnetic resonance imaging (fMRI), statistical parametric mapping (SPM5) and dynamic causal modelling (DCM). A silent imaging paradigm was used to reduce the scanner sound artefacts on functional images. The subjects were instructed to pay attention to the white noise stimulus binaurally given at intensity level of 70 dB higher than the hearing level for normal people. Functional specialisation was studied using Matlab-based SPM5 software by means of fixed effects (FFX), random effects (RFX) and conjunction analyses. Individual analyses on all subjects indicate asymmetrical bilateral activation between the left and right auditory cortices in Brodmann areas (BA)22, 41 and 42 involving the primary and secondary auditory cortices. The three auditory areas in the right and left auditory cortices are selected for the determination of the effective connectivity by constructing 9 network models. The effective connectivity is determined on four out of five subjects with the exception of one subject who has the BA22 coordinates located too far from BA22 coordinates obtained from group analysis. DCM results showed the existence of effective connectivity between the three selected auditory areas in both auditory cortices. In the right auditory cortex, BA42 is identified as input centre with unidirectional parallel effective connectivities of BA42→BA41and BA42→BA22. However, for the left auditory cortex, the input is BA41 with unidirectional parallel effective connectivities of BA41→BA42 and BA41→BA22. The connectivity between the activated auditory areas suggests the existence of signal pathway in the auditory cortices even when the subject is listening to noise. (author)

  5. The effective fragment molecular orbital method for fragments connected by covalent bonds.

    Directory of Open Access Journals (Sweden)

    Casper Steinmann

    Full Text Available We extend the effective fragment molecular orbital method (EFMO into treating fragments connected by covalent bonds. The accuracy of EFMO is compared to FMO and conventional ab initio electronic structure methods for polypeptides including proteins. Errors in energy for RHF and MP2 are within 2 kcal/mol for neutral polypeptides and 6 kcal/mol for charged polypeptides similar to FMO but obtained two to five times faster. For proteins, the errors are also within a few kcal/mol of the FMO results. We developed both the RHF and MP2 gradient for EFMO. Compared to ab initio, the EFMO optimized structures had an RMSD of 0.40 and 0.44 Å for RHF and MP2, respectively.

  6. Investigating the effects of streamline-based fiber tractography on matrix scaling in brain connective network.

    Science.gov (United States)

    Jan, Hengtai; Chao, Yi-Ping; Cho, Kuan-Hung; Kuo, Li-Wei

    2013-01-01

    Investigating the brain connective network using the modern graph theory has been widely applied in cognitive and clinical neuroscience research. In this study, we aimed to investigate the effects of streamline-based fiber tractography on the change of network properties and established a systematic framework to understand how an adequate network matrix scaling can be determined. The network properties, including degree, efficiency and betweenness centrality, show similar tendency in both left and right hemispheres. By employing the curve-fitting process with exponential law and measuring the residuals, the association between changes of network properties and threshold of track numbers is found and an adequate range of investigating the lateralization of brain network is suggested. The proposed approach can be further applied in clinical applications to improve the diagnostic sensitivity using network analysis with graph theory.

  7. Bupropion Shows Different Effects on Brain Functional Connectivity in Patients With Internet-Based Gambling Disorder and Internet Gaming Disorder

    Directory of Open Access Journals (Sweden)

    Sujin Bae

    2018-04-01

    Full Text Available IntroductionInternet gaming disorder (IGD and gambling disorder (GD share similar clinical characteristics but show different brain functional connectivity patterns. Bupropion is known to be effective for the treatment of patients with IGD and GD. We hypothesized that bupropion may be effective for the treatment of Internet-based gambling disorder (ibGD and IGD and that the connections between the default mode network (DMN and cognitive control network (CCN would be different between ibGD and IGD patients after 12 weeks of bupropion treatment.Methods16 patients with IGD, 15 patients with ibGD, and 15 healthy subjects were recruited in this study. At baseline and after 12 weeks of bupropion treatment, the clinical symptoms of patients with IGD or ibGD were assessed, and brain activity was evaluated using resting state functional magnetic resonance imaging.ResultsAfter the 12-week bupropion treatment, clinical symptoms, including the severity of IGD or GD, depressive symptoms, attention, and impulsivity improved in both groups. In the IGD group, the functional connectivity (FC within the posterior DMN as well as the FC between the DMN and the CCN decreased following treatment. Moreover, the FC within the DMN in the IGD group was positively correlated with changes in Young Internet Addiction Scale scores after the bupropion treatment period. In the ibGD group, the FC within the posterior DMN decreased while the FC within the CCN increased after the bupropion treatment period. Moreover, the FC within the CCN in the ibGD group was significantly greater than that in the IGD group.ConclusionBupropion was effective in improving clinical symptoms in patients with IGD and ibGD. However, there were differences in the pharmacodynamics between the two groups. After 12 weeks of bupropion treatment, the FC within the DMN as well as between the DMN and CCN decreased in patients with IGD, whereas the FC within the CCN increased in patients with ibGD.

  8. Collagenous sprue: Don't forget connective tissue in chronic diarrhea evaluation

    Directory of Open Access Journals (Sweden)

    Victoria Busto-Bea

    2013-03-01

    Full Text Available Collagenous sprue is a rare disease of the small bowel characterized by mucosal atrophy and excessive subepithelial collagen deposition. The etiology remains unclear and the diagnosis is based upon patient's clinical picture and anatomopathological findings. Clinically, collagenous sprue is characterized by persistent diarrhoea, severe malabsorption, multiple nutrient deficiencies and progressive weight loss. Differential diagnosis includes celiac disease, which is mandatory to rule out because of their frequent association. Gluten-free diet is the first therapeutic step, but it usually is not effective. However, recent studies show high success rates with immunomodulators, mainly corticosteroids. We report the case of a patient presenting with chronic diarrhea and severe malabsorption who was diagnosed with collagenous sprue, with no response to gluten free diet, but with excellent response to budesonida.

  9. Effects of resveratrol on memory performance, hippocampal functional connectivity, and glucose metabolism in healthy older adults.

    Science.gov (United States)

    Witte, A Veronica; Kerti, Lucia; Margulies, Daniel S; Flöel, Agnes

    2014-06-04

    Dietary habits such as caloric restriction or nutrients that mimic these effects may exert beneficial effects on brain aging. The plant-derived polyphenol resveratrol has been shown to increase memory performance in primates; however, interventional studies in older humans are lacking. Here, we tested whether supplementation of resveratrol would enhance memory performance in older adults and addressed potential mechanisms underlying this effect. Twenty-three healthy overweight older individuals that successfully completed 26 weeks of resveratrol intake (200 mg/d) were pairwise matched to 23 participants that received placebo (total n = 46, 18 females, 50-75 years). Before and after the intervention/control period, subjects underwent memory tasks and neuroimaging to assess volume, microstructure, and functional connectivity (FC) of the hippocampus, a key region implicated in memory functions. In addition, anthropometry, glucose and lipid metabolism, inflammation, neurotrophic factors, and vascular parameters were assayed. We observed a significant effect of resveratrol on retention of words over 30 min compared with placebo (p = 0.038). In addition, resveratrol led to significant increases in hippocampal FC, decreases in glycated hemoglobin (HbA1c) and body fat, and increases in leptin compared with placebo (all p memory performance in association with improved glucose metabolism and increased hippocampal FC in older adults. Our findings offer the basis for novel strategies to maintain brain health during aging. Copyright © 2014 the authors 0270-6474/14/347862-09$15.00/0.

  10. Enhanced heat rectification effect in a quantum dot connected to ferromagnetic leads

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Feng, E-mail: chifeng@semi.ac.cn [School of Physical Science and Technology, Inner Mongolia University, Huhehaote 010023 (China); College of Engineering, Bohai University, Jinzhou 121013 (China); Sun, Lian-Liang [College of Science, North China University of Technology, Beijing 100041 (China); Zheng, Jun; Guo, Yu [College of Engineering, Bohai University, Jinzhou 121013 (China)

    2015-06-15

    We study theoretically the heat generation by electric current in an interacting single level quantum-dot connected to ferromagnetic leads. The heat is transferred between the dot and the lattice vibration of its host material (phonon reservoir). Particular attention is paid on the heat's rectification effect achieved by properly arranging the dot level and the bias voltage. We find that this effect is remarkably enhanced when the two leads' magnetic moments are in antiparallel configuration, i.e., the magnitude of the heat generation is reduced (amplified) in the negative (positive) bias regime as compared to the cases of parallel configuration and nonmagnetic leads. The rectification effect is even enhanced when one of the lead's spin polarization approaches to unit, during which the negative differential of the heat generation is weakened due to the change of the spin-dependent electron occupation numbers on the dot. The found results may be used for thermal transistor in the newly emerged research subject of phononics. - Highlights: • Heat flow between electrons and phonons is controlled by interaction between them. • A thermal diode or rectifier is proposed to work under electrical bias. • The heat rectification effect can be enhanced by the leads' ferromagnetism.

  11. Relative effects of road risk, habitat suitability, and connectivity on wildlife roadkills: the case of tawny owls (Strix aluco).

    Science.gov (United States)

    Santos, Sara M; Lourenço, Rui; Mira, António; Beja, Pedro

    2013-01-01

    Despite its importance for reducing wildlife-vehicle collisions, there is still incomplete understanding of factors responsible for high road mortality. In particular, few empirical studies examined the idea that spatial variation in roadkills is influenced by a complex interplay between road-related factors, and species-specific habitat quality and landscape connectivity. In this study we addressed this issue, using a 7-year dataset of tawny owl (Strix aluco) roadkills recorded along 37 km of road in southern Portugal. We used a multi-species roadkill index as a surrogate of intrinsic road risk, and we used a Maxent distribution model to estimate habitat suitability. Landscape connectivity was estimated from least-cost paths between tawny owl territories, using habitat suitability as a resistance surface. We defined 10 alternative scenarios to compute connectivity, based on variation in potential movement patterns according to territory quality and dispersal distance thresholds. Hierarchical partitioning of a regression model indicated that independent variation in tawny owl roadkills was explained primarily by the roadkill index (70.5%) and, to a much lesser extent, by landscape connectivity (26.2%), while habitat suitability had minor effects (3.3%). Analysis of connectivity scenarios suggested that owl roadkills were primarily related to short range movements (habitat quality and landscape connectivity are globally high for the study species. Nevertheless, the study supported the view that functional connectivity should be incorporated whenever possible in roadkill models, as it may greatly increase their power to predict the location of roadkill hotspots.

  12. The Effects of Long Duration Bed Rest as a Spaceflight Analogue on Resting State Sensorimotor Network Functional Connectivity and Neurocognitive Performance

    Science.gov (United States)

    Cassady, K.; Koppelmans, V.; Yuan, P.; Cooke, K.; De Dios, Y.; Stepanyan, V.; Szecsy, D.; Gadd, N.; Wood, S.; Reuter-Lorenz, P.; hide

    2015-01-01

    Long duration spaceflight has been associated with detrimental alterations in human sensorimotor systems and neurocognitive performance. Prolonged exposure to a head-down tilt position during long duration bed rest can resemble several effects of the microgravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The question of whether microgravity affects other central nervous system functions such as brain functional connectivity and its relationship with neurocognitive performance is largely unknown, but of potential importance to the health and performance of astronauts both during and post-flight. The aims of the present study are 1) to identify changes in sensorimotor resting state functional connectivity that occur with extended bed rest exposure, and to characterize their recovery time course; 2) to evaluate how these neural changes correlate with neurocognitive performance. Resting-state functional magnetic resonance imaging (rsfMRI) data were collected from 17 male participants. The data were acquired through the NASA bed rest facility, located at the University of Texas Medical Branch (Galveston, TX). Participants remained in bed with their heads tilted down six degrees below their feet for 70 consecutive days. RsfMRI data were obtained at seven time points: 7 and 12 days before bed rest; 7, 50, and 65 days during bed rest; and 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (fcMRI) analysis was performed to measure the connectivity of sensorimotor networks in the brain before, during, and post-bed rest. We found a decrease in left putamen connectivity with the pre- and post-central gyri from pre bed rest to the last day in bed rest. In addition, vestibular cortex connectivity with the posterior cingulate cortex decreased from pre to post bed rest. Furthermore, connectivity between cerebellar right superior posterior fissure and other cerebellar regions decreased from

  13. EVALUATION OF ALTERNATIVE RAILWAY CONNECTION ACCESS AT JAKARTA SOEKARNO HATTA INTERNATIONAL AIRPORT

    Directory of Open Access Journals (Sweden)

    Ayu Aprilischa

    2015-01-01

    Full Text Available Traveling between the center of Jakarta and Soekarno Hatta International Airport (SHIA is further constrained by the limited number of main routes available which likely cannot be accommodated in the future by road based transport modes alone. Hence, the airport needs to develop airport surface access to accommodate its network. The aim of this research is to analyze the railway access system for developing the system of SHIA using multi criteria analysis in the selection of alternative route alignment of the railway line and a qualitative study in data collection within the research design. Development of the criteria includes technical, economic, environmental and spatial aspect. Three alternatives have been proposed in this analysis, i.e. through West Jakarta, through North and West Jakarta and through North and Central Jakarta. The results show that alternative 3 (through North and Central Jakarta can give implications to the airport users, i.e. providing a high standard of the rail link in a well-timed manner and a cost-effective public transport link. Improving the multi-modal access to the airport will improve the supply of employment to business, lead to urban regeneration around station locations, and improve Greater Jakarta Metropolitan Area regional competitiveness.

  14. Finiteness effects in wideband connected arrays: Analytical models to highlight the effects of the loading impedances

    NARCIS (Netherlands)

    Neto, A.; Cavallo, D.; Gerini, G.

    2011-01-01

    Most phased arrays are designed using infinite array theory, which does not account for edge effects. However, this approximation might not be adequate for the design of wideband arrays, for which truncation effects are more significant than in traditional narrow-band arrays. In particular, edge

  15. Connecting Medical Records: An Evaluation of Benefits and Challenges for Primary Care Practices

    Directory of Open Access Journals (Sweden)

    Deborah Ruth Compeau

    2017-06-01

    Full Text Available Background: Implementation of systems to support health information sharing has lagged other areas of healthcare IT, yet offers a strong possibility for benefit.  Clinical acceptance is a key limiting factor in health IT adoption. Objectives:  To assess the benefits and challenges experienced by clinicians using a custom-developed health information exchange system, and to show how perceptions of benefits and challenges influence perceptions of productivity and care-related outcomes. Methods: We used a mixed methods design with two phases. First, we conducted interviews with stakeholders who were familiar with the health information exchange system to inform the development of a measure of benefits and challenges of the use of this system. Second, using this measure we conducted a survey of current and former users of the health information exchange system using a modified Dillman method. Results: 105 current and former users completed the survey. The results showed information quality, ease of completing tasks and clinical process improvement as key benefits that reduced workload and improved patient care.  Challenges related to system reliability, quality of reports and service quality increased workload and decreased impact on care, though the effect of the challenges was smaller than that of the benefits. Conclusions:  Even very limited health information exchange capabilities can improve outcomes for primary care users.  Improving perceptions of benefits may be even more important the removing challenges to use, though it is likely that a threshold of quality must be achieved for this to be true.

  16. Effects of gratitude meditation on neural network functional connectivity and brain-heart coupling.

    Science.gov (United States)

    Kyeong, Sunghyon; Kim, Joohan; Kim, Dae Jin; Kim, Hesun Erin; Kim, Jae-Jin

    2017-07-11

    A sense of gratitude is a powerful and positive experience that can promote a happier life, whereas resentment is associated with life dissatisfaction. To explore the effects of gratitude and resentment on mental well-being, we acquired functional magnetic resonance imaging and heart rate (HR) data before, during, and after the gratitude and resentment interventions. Functional connectivity (FC) analysis was conducted to identify the modulatory effects of gratitude on the default mode, emotion, and reward-motivation networks. The average HR was significantly lower during the gratitude intervention than during the resentment intervention. Temporostriatal FC showed a positive correlation with HR during the gratitude intervention, but not during the resentment intervention. Temporostriatal resting-state FC was significantly decreased after the gratitude intervention compared to the resentment intervention. After the gratitude intervention, resting-state FC of the amygdala with the right dorsomedial prefrontal cortex and left dorsal anterior cingulate cortex were positively correlated with anxiety scale and depression scale, respectively. Taken together, our findings shed light on the effect of gratitude meditation on an individual's mental well-being, and indicate that it may be a means of improving both emotion regulation and self-motivation by modulating resting-state FC in emotion and motivation-related brain regions.

  17. The effect of binaural beats on verbal working memory and cortical connectivity

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A.; Leonessa, Alexander

    2017-04-01

    Objective. Synchronization in activated regions of cortical networks affect the brain’s frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain’s response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. Approach. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. Main results. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant’s accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Significance. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  18. The effect of binaural beats on verbal working memory and cortical connectivity.

    Science.gov (United States)

    Beauchene, Christine; Abaid, Nicole; Moran, Rosalyn; Diana, Rachel A; Leonessa, Alexander

    2017-04-01

    Synchronization in activated regions of cortical networks affect the brain's frequency response, which has been associated with a wide range of states and abilities, including memory. A non-invasive method for manipulating cortical synchronization is binaural beats. Binaural beats take advantage of the brain's response to two pure tones, delivered independently to each ear, when those tones have a small frequency mismatch. The mismatch between the tones is interpreted as a beat frequency, which may act to synchronize cortical oscillations. Neural synchrony is particularly important for working memory processes, the system controlling online organization and retention of information for successful goal-directed behavior. Therefore, manipulation of synchrony via binaural beats provides a unique window into working memory and associated connectivity of cortical networks. In this study, we examined the effects of different acoustic stimulation conditions during an N-back working memory task, and we measured participant response accuracy and cortical network topology via EEG recordings. Six acoustic stimulation conditions were used: None, Pure Tone, Classical Music, 5 Hz binaural beats, 10 Hz binaural beats, and 15 Hz binaural beats. We determined that listening to 15 Hz binaural beats during an N-Back working memory task increased the individual participant's accuracy, modulated the cortical frequency response, and changed the cortical network connection strengths during the task. Only the 15 Hz binaural beats produced significant change in relative accuracy compared to the None condition. Listening to 15 Hz binaural beats during the N-back task activated salient frequency bands and produced networks characterized by higher information transfer as compared to other auditory stimulation conditions.

  19. Technical evaluation of a tank-connected food waste disposer system for biogas production and nutrient recovery.

    Science.gov (United States)

    Davidsson, Å; Bernstad Saraiva, A; Magnusson, N; Bissmont, M

    2017-07-01

    In this study, a tank-connected food waste disposer system with the objective to optimise biogas production and nutrient recovery from food waste in Malmö was evaluated. The project investigated the source-separation ratio of food waste through waste composition analyses, determined the potential biogas production in ground food waste, analysed the organic matter content and the limiting components in ground food waste and analysed outlet samples to calculate food waste losses from the separation tank. It can be concluded that the tank-connected food waste disposer system in Malmö can be used for energy recovery and optimisation of biogas production. The organic content of the collected waste is very high and contains a lot of energy rich fat and protein, and the methane potential is high. The results showed that approximately 38% of the food waste dry matter is collected in the tank. The remaining food waste is either found in residual waste (34% of the dry matter) or passes the tank and goes through the outlet to the sewer (28%). The relatively high dry matter content in the collected fraction (3-5% DM) indicates that the separation tank can thicken the waste substantially. The potential for nutrient recovery is rather limited considering the tank content. Only small fractions of the phosphorus (15%) and nitrogen (21%) are recyclable by the collected waste in the tank. The quality of the outlet indicates a satisfactory separation of particulate organic matter and fat. The organic content and nutrients, which are in dissolved form, cannot be retained in the tank and are rather led to the sewage via the outlet. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The Evaluator Effect in Usability Tests

    DEFF Research Database (Denmark)

    Jacobsen, Niels Ebbe; Hertzum, Morten; John, Bonnie E.

    1998-01-01

    Usability tests are applied in industry to evaluate systems and in research as a yardstick for other usability evaluation methods. However, one potential threat to the reliability of usability tests has been left unaddressed: the evaluator effect. In this study, four evaluators analyzed four vide...

  1. Grid-connected photovoltaic systems for Malaysian residential sector: Effects of component costs, feed-in tariffs, and carbon taxes

    International Nuclear Information System (INIS)

    Lau, K.Y.; Muhamad, N.A.; Arief, Y.Z.; Tan, C.W.; Yatim, A.H.M.

    2016-01-01

    Blessed with abundant solar radiation, Malaysia has a huge potential for grid-connected PV (photovoltaic) installations, particularly for its fast-growing residential sector. Nevertheless, Malaysia's PV installation capacity is relatively small compared with the global PV capacity. Significantly, the pricing mechanisms for grid-connected PV projects need to be appropriately assessed to build up the public's confidence to invest in PV projects. In this paper, we analyze the effects of component costs, FiTs (feed-in tariffs), and carbon taxes on grid-connected PV systems in Malaysian residential sector using the HOMER (Hybrid Optimization of Multiple Energy Resources) software. Results demonstrate that the implementation of grid-connected PV systems is highly feasible with PV array costs of $ 1120/kW or lower. For higher PV array costs up to $ 2320/kW, introducing an FiT rate three times higher ($ 0.30/kWh) than the grid tariff for a 100 kW grid sale capacity will, NPC-wise, prioritize grid-connected PV systems over the utility grid. By implementing the FiT ($ 0.50/kWh) and the carbon tax ($ 36/metric ton) schemes simultaneously, grid-connected PV systems will remain as the optimal systems even for costly PV arrays (up to $ 4000/kW). The findings are of paramount importance as far as PV pricing variability is concerned. - Highlights: • Grid-connected PV for Malaysian residential sector has been analyzed using HOMER. • Component costs, feed-in tariffs, and carbon taxes affect optimal system types. • Grid-connected PV projects are feasible for low PV array costs ($ 1120/kW or lower). • For higher PV array and inverter costs, feed-in tariffs should be implemented. • Combining feed-in tariffs with carbon taxes are effective for further lowering NPCs.

  2. Effect of temperature on microbial growth rate - thermodynamic analysis, the arrhenius and eyring-polanyi connection

    Science.gov (United States)

    The objective of this work is to develop a new thermodynamic mathematical model for evaluating the effect of temperature on the rate of microbial growth. The new mathematical model is derived by combining the Arrhenius equation and the Eyring-Polanyi transition theory. The new model, suitable for ...

  3. Evaluation of the Trajectory Sensitivity Analysis of the DFIG Control Parameters in Response to Changes in Wind Speed and the Line Impedance Connection to the Grid DFIG

    Directory of Open Access Journals (Sweden)

    Mehdi Fooladgar

    2015-01-01

    Full Text Available Economic and environmental conditions often make large stations and transmission lines, restrictions are placed. Small and medium-sized production units connected to existing systems as a strategy is in progress. These units are usually near the center of the load placed and distributed generators (DG famous are the DG are allowed types vary, such as induction generators rack squirrel-connected wind turbines, generators fed induction double mounted wind turbines, fuel cells connected to the system by power electronic converters or synchronous generator connected to the turbine combustion [10]. This way sensitivity analysis in systems of distributed generation (DG is assessed. It is shown that the method can detect the effect of control parameters listed wind turbine connected to a double-fed induction generator (DFIG Badoou the impedance of the changing the speed of on the stability of the transmission line useful system invested. The control parameters of the importance of influencing the behavior of DFIG are divided.

  4. Using GIS to evaluate the impact of exclusion zones on the connection cost of wave energy to the electricity grid

    International Nuclear Information System (INIS)

    Prest, Robert; Daniell, Trevor; Ostendorf, Bertram

    2007-01-01

    An increase in the planning and environmental restrictions associated with wind energy has led to a growth in interest towards wave energy. However, as the connection cost of a wave energy development is a driving factor in the development's feasibility, existing wind farm cable-routing techniques used by renewable energy developers may not be satisfactory. A Geographical Information System (GIS) method is presented which optimises the cable route between a wave farm and the electricity network, while taking a range of exclusion zones, such as native vegetation, into account. The optimisation is presented for a South Australian study area, which subsequently showed that exclusion zones reduce the number of suitable locations for wave energy by almost 40%. The method presented also assesses the effect that each exclusion zone applied has upon the number of suitable locations within the study area. The analysis undertaken showed that National Parks and cliffs pose a significant limitation to the potential of a wave energy industry within South Australia. Allowing the transmission route to travel through a National Park, or traverse a cliff, resulted in an increase in the number of locations from which a connection could be made to the electricity grid for less than $10 million of 33% and 50%, respectively. Conservation Parks, Wilderness Areas and native vegetation also have an effect upon the number of suitable locations for wave energy within South Australia. The GIS methods developed may be of assistance to governments in setting appropriate marine renewable energy policy, and also in identifying existing policy which may require amending if the government wishes to pursue and support the development of wave energy

  5. Effect of fiberglass reinforcement on the behavior of bolted wood connections

    Science.gov (United States)

    Lawrence A. Soltis; Robert J. Ross; Daniel E. Windorski

    1997-01-01

    Bolted connections often fail by a shear plug or by splitting beneath the bolt caused by tension perpendicular-to-grain stress as the bolt wedges its way through the wood. Preventing this type of failure enhances both the capacity and reliability of bolted connections. This research investigated the use of fiberglass reinforcement to enhance the load-carrying capacity...

  6. Emotional face expression modulates occipital-frontal effective connectivity during memory formation in a bottom-up fashion

    Directory of Open Access Journals (Sweden)

    Daiming eXiu

    2015-04-01

    Full Text Available This study investigated the role of bottom-up and top-down neural mechanisms in the processing of emotional face expression during memory formation. Functional brain imaging data was acquired during incidental learning of positive (‘happy’, neutral and negative (‘angry’ or ‘fearful’ faces. Dynamic Causal Modeling (DCM was applied on the fMRI data to characterize effective connectivity within a brain network involving face perception (inferior occipital gyrus and fusiform gyrus and successful memory formation related areas (hippocampus, superior parietal lobule, amygdala and orbitofrontal cortex. The bottom-up models assumed processing of emotional face expression along feed forward pathways to the orbitofrontal cortex. The top-down models assumed that the orbitofrontal cortex processed emotional valence and mediated connections to the hippocampus. A subsequent recognition memory test showed an effect of negative emotion on the response bias, but not on memory performance. Our DCM findings showed that the bottom-up model family of effective connectivity best explained the data across all subjects and specified that emotion affected most bottom-up connections to the orbitofrontal cortex, especially from the occipital visual cortex and superior parietal lobule. Of those pathways to the orbitofrontal cortex the connection from the inferior occipital gyrus correlated with memory performance independently of valence. We suggest that bottom-up neural mechanisms support effects of emotional face expression and memory formation in a parallel and partially overlapping fashion.

  7. Age-related difference in the effective neural connectivity associated with probabilistic category learning

    International Nuclear Information System (INIS)

    Yoon, Eun Jin; Cho, Sang Soo; Kim, Hee Jung; Bang, Seong Ae; Park, Hyun Soo; Kim, Yu Kyeong; Kim, Sang Eun

    2007-01-01

    Although it is well known that explicit memory is affected by the deleterious changes in brain with aging, but effect of aging in implicit memory such as probabilistic category learning (PCL) is not clear. To identify the effect of aging on the neural interaction for successful PCL, we investigated the neural substrates of PCL and the age-related changes of the neural network between these brain regions. 23 young (age, 252 y; 11 males) and 14 elderly (673 y; 7 males) healthy subjects underwent FDG PET during a resting state and 150-trial weather prediction (WP) task. Correlations between the WP hit rates and regional glucose metabolism were assessed using SPM2 (P diff (37) = 142.47, P<0.005), Systematic comparisons of each path revealed that frontal crosscallosal and the frontal to parahippocampal connection were most responsible for the model differences (P<0.05). For the successful PCL, the elderly recruits the basal ganglia implicit memory system but MTL recruitment differs from the young. The inadequate MTL correlation pattern in the elderly is may be caused by the changes of the neural pathway related with explicit memory. These neural changes can explain the decreased performance of PCL in elderly subjects

  8. Disrupted Thalamus White Matter Anatomy and Posterior Default Mode Network Effective Connectivity in Amnestic Mild Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Thomas Alderson

    2017-11-01

    Full Text Available Alzheimer’s disease (AD and its prodromal state amnestic mild cognitive impairment (aMCI are characterized by widespread abnormalities in inter-areal white matter fiber pathways and parallel disruption of default mode network (DMN resting state functional and effective connectivity. In healthy subjects, DMN and task positive network interaction are modulated by the thalamus suggesting that abnormal task-based DMN deactivation in aMCI may be a consequence of impaired thalamo-cortical white matter circuitry. Thus, this article uses a multimodal approach to assess white matter integrity between thalamus and DMN components and associated effective connectivity in healthy controls (HCs relative to aMCI patients. Twenty-six HC and 20 older adults with aMCI underwent structural, functional and diffusion MRI scanning using the high angular resolution diffusion-weighted acquisition protocol. The DMN of each subject was identified using independent component analysis (ICA and resting state effective connectivity was calculated between thalamus and DMN nodes. White matter integrity changes between thalamus and DMN were investigated with constrained spherical deconvolution (CSD tractography. Significant structural deficits in thalamic white matter projection fibers to posterior DMN components posterior cingulate cortex (PCC and lateral inferior parietal lobe (IPL were identified together with significantly reduced effective connectivity from left thalamus to left IPL. Crucially, impaired thalamo-cortical white matter circuitry correlated with memory performance. Disrupted thalamo-cortical structure was accompanied by significant reductions in IPL and PCC cortico-cortical effective connectivity. No structural deficits were found between DMN nodes. Abnormal posterior DMN activity may be driven by changes in thalamic white matter connectivity; a view supported by the close anatomical and functional association of thalamic nuclei effected by AD pathology and

  9. Lasting modulation effects of rTMS on neural activity and connectivity as revealed by resting-state EEG.

    Science.gov (United States)

    Ding, Lei; Shou, Guofa; Yuan, Han; Urbano, Diamond; Cha, Yoon-Hee

    2014-07-01

    The long-lasting neuromodulatory effects of repetitive transcranial magnetic stimulation (rTMS) are of great interest for therapeutic applications in various neurological and psychiatric disorders, due to which functional connectivity among brain regions is profoundly disturbed. Classic TMS studies selectively alter neural activity in specific brain regions and observe neural activity changes on nonperturbed areas to infer underlying connectivity and its changes. Less has been indicated in direct measures of functional connectivity and/or neural network and on how connectivity/network alterations occur. Here, we developed a novel analysis framework to directly investigate both neural activity and connectivity changes induced by rTMS from resting-state EEG (rsEEG) acquired in a group of subjects with a chronic disorder of imbalance, known as the mal de debarquement syndrome (MdDS). Resting-state activity in multiple functional brain areas was identified through a data-driven blind source separation analysis on rsEEG data, and the connectivity among them was characterized using a phase synchronization measure. Our study revealed that there were significant long-lasting changes in resting-state neural activity, in theta, low alpha, and high alpha bands and neural networks in theta, low alpha, high alpha and beta bands, over broad cortical areas 4 to 5 h after the last application of rTMS in a consecutive five-day protocol. Our results of rsEEG connectivity further indicated that the changes, mainly in the alpha band, over the parietal and occipital cortices from pre- to post-TMS sessions were significantly correlated, in both magnitude and direction, to symptom changes in this group of subjects with MdDS. This connectivity measure not only suggested that rTMS can generate positive treatment effects in MdDS patients, but also revealed new potential targets for future therapeutic trials to improve treatment effects. It is promising that the new connectivity measure

  10. Lithium monotherapy associated clinical improvement effects on amygdala-ventromedial prefrontal cortex resting state connectivity in bipolar disorder.

    Science.gov (United States)

    Altinay, Murat; Karne, Harish; Anand, Amit

    2018-01-01

    This study, for the first time, investigated lithium monotherapy associated effects on amygdala- ventromedial prefrontal cortex (vMPFC) resting-state functional connectivity and correlation with clinical improvement in bipolar disorder (BP) METHODS: Thirty-six medication-free subjects - 24 BP (12 hypomanic BPM) and 12 depressed (BPD)) and 12 closely matched healthy controls (HC), were included. BP subjects were treated with lithium and scanned at baseline, after 2 weeks and 8 weeks. HC were scanned at same time points but were not treated. The effect of lithium was studied for the BP group as a whole using two way (group, time) ANOVA while regressing out effects of state. Next, correlation between changes in amygdala-vMPFC resting-state connectivity and clinical global impression (CGI) of severity and improvement scale scores for overall BP illness was calculated. An exploratory analysis was also conducted for the BPD and BPM subgroups separately. Group by time interaction revealed that lithium monotherapy in patients was associated with increase in amygdala-medial OFC connectivity after 8 weeks of treatment (p = 0.05 (cluster-wise corrected)) compared to repeat testing in healthy controls. Increased amygdala-vMPFC connectivity correlated with clinical improvement at week 2 and week 8 as measured with the CGI-I scale. The results pertain to open-label treatment and do not account for non-treatment related improvement effects. Only functional connectivity was measured which does not give information regarding one regions effect on the other. Lithium monotherapy in BP is associated with modulation of amygdala-vMPFC connectivity which correlates with state-independent global clinical improvement. Copyright © 2017. Published by Elsevier B.V.

  11. Effect of the channel electron multiplier connection diagram on its parameters

    International Nuclear Information System (INIS)

    Ajnbund, M.R.

    1976-01-01

    Basic alternatives of connection of a channel electron multiplier are described. A dependence of a gain factor and amplitude resolution of the channel electron multiplier upon its connection diagram is studied. The studies have shown that the maximum gain factor is typical of an open-output circuit where the signal is recorded from the anode of the channel electron multiplier at a potential with respect to the channel outlet. The highest amplitude resolution is inherent in a separate-anode circuit where the loading resistance is connected directly to the channel outlet

  12. Cosmic Connections

    CERN Document Server

    Ellis, Jonathan Richard

    2003-01-01

    A National Research Council study on connecting quarks with the cosmos has recently posed a number of the more important open questions at the interface between particle physics and cosmology. These questions include the nature of dark matter and dark energy, how the Universe began, modifications to gravity, the effects of neutrinos on the Universe, how cosmic accelerators work, and whether there are new states of matter at high density and pressure. These questions are discussed in the context of the talks presented at this Summer Institute.

  13. Hydrogeomorphic connectivity on roads crossing in rural headwaters and its effect on stream dynamics.

    Science.gov (United States)

    Thomaz, Edivaldo L; Peretto, Gustavo T

    2016-04-15

    Unpaved roads are ubiquitous features that have been transforming the landscape through human history. Unpaved roads affect the water and sediment pathways through a catchment and impacts the aquatic ecosystem. In this study, we describe the effect of unpaved road on the hydrogeomorphic connectivity at the rural headwater scale. Measurement was based on the stream crossing approach, i.e., road superimposing the drainage system. We installed a Parshall flume coupled with single-stage suspended sediment sampler at each stream crossing. In addition, we displayed our monitoring scheme with an upscaling perspective from second-order to third-order stream. We concluded that the road-stream coupling dramatically changed the stream dynamic. The increase of discharge caused by roads at the headwater was 50% larger compared to unaffected streams. Additionally, suspended sediment concentration enhancement at stream crossings ranged from to 413% at second-order streams to 145% at third-order streams. The landform characteristics associated with the road network produced an important hydrogeomorphic disruption in the landscape. As a result, the sediment filter function of the riparian zone was reduced dramatically. Therefore, we recommend that projects for aquatic system restoration or conservation in rural landscape consider the role of the road network on stream dynamics. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Effective connectivity within the default mode network: dynamic causal modeling of resting-state fMRI data

    Directory of Open Access Journals (Sweden)

    Maksim eSharaev

    2016-02-01

    Full Text Available The Default Mode Network (DMN is a brain system that mediates internal modes of cognitive activity, showing higher neural activation when one is at rest. Nowadays, there is a lot of interest in assessing functional interactions between its key regions, but in the majority of studies only association of BOLD (Blood-oxygen-level dependent activation patterns is measured, so it is impossible to identify causal influences. There are some studies of causal interactions (i.e. effective connectivity, however often with inconsistent results. The aim of the current work is to find a stable pattern of connectivity between four DMN key regions: the medial prefrontal cortex mPFC, the posterior cingulate cortex PCC, left and right intraparietal cortex LIPC and RIPC. For this purpose fMRI (functional magnetic resonance imaging data from 30 healthy subjects (1000 time points from each one was acquired and spectral dynamic causal modeling (DCM on a resting-state fMRI data was performed. The endogenous brain fluctuations were explicitly modeled by Discrete Cosine Set at the low frequency band of 0.0078–0.1 Hz. The best model at the group level is the one where connections from both bilateral IPC to mPFC and PCC are significant and symmetrical in strength (p<0.05. Connections between mPFC and PCC are bidirectional, significant in the group and weaker than connections originating from bilateral IPC. In general, all connections from LIPC/RIPC to other DMN regions are much stronger. One can assume that these regions have a driving role within the DMN. Our results replicate some data from earlier works on effective connectivity within the DMN as well as provide new insights on internal DMN relationships and brain’s functioning at resting state.

  15. Evaluating the impact of electrical grid connection on the wind turbine performance for Hofa wind farm scheme in Jordan

    International Nuclear Information System (INIS)

    Abderrazzaq, M.H.; Aloquili, O.

    2008-01-01

    The growth of wind energy is attributed to the development of turbine size and the increase in number of units in each wind farm. The current modern design of large wind turbines (WT) is directed towards producing efficient, sensitive and reliable units. To achieve this goal, modern turbines are equipped with several devices which are operated with highly advanced electronic circuits. Sensing instruments, measuring devices and control processes of major systems and subsystems are based on various types of electronic apparatus and boards. These boards are very sensitive to the voltage variations caused by abnormal conditions in both the turbine itself and the electric grid to which the wind farm is connected. This paper evaluates wind farm records and proposes a number of methods to overcome such obstacles associated with the design of large wind turbines. Several cases of grid abnormality such as sudden feeder interruption due to the short circuit, network disconnection, voltage variation and circuit breaker opening affecting wind turbines operation and availability are classified and presented. The weight of such impact is determined for each type of disturbances associated with electronic problems in the wind turbine. Wind turbine performance at Hofa wind farm scheme in Jordan is taken as a case study

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

    Directory of Open Access Journals (Sweden)

    Maria de la Iglesia-Vaya

    2014-01-01

    These data indicate that an anomalous process of neural connectivity exists when patients with AH process emotional auditory stimuli. Additionally, a central role is suggested for the cerebellum in processing emotional stimuli in patients with persistent AH.

  17. Characterizing the Connectivity and Cumulative Effects of Wetlands on Downstream Hydrology: A Modeling Analysis

    Science.gov (United States)

    Geographically isolated wetlands (GIWs) are depressional landscape features entirely surrounded by uplands. While “GIW” may imply functional isolation from other surface waters, these systems exhibit a gradient of hydrologic, biological, and/or chemical connectivity. ...

  18. The Effects of rTMS Combined with Motor Training on Functional Connectivity in Alpha Frequency Band.

    Science.gov (United States)

    Jin, Jing-Na; Wang, Xin; Li, Ying; Jin, Fang; Liu, Zhi-Peng; Yin, Tao

    2017-01-01

    It has recently been reported that repetitive transcranial magnetic stimulation combined with motor training (rTMS-MT) could improve motor function in post-stroke patients. However, the effects of rTMS-MT on cortical function using functional connectivity and graph theoretical analysis remain unclear. Ten healthy subjects were recruited to receive rTMS immediately before application of MT. Low frequency rTMS was delivered to the dominant hemisphere and non-dominant hand performed MT over 14 days. The reaction time of Nine-Hole Peg Test and electroencephalography (EEG) in resting condition with eyes closed were recorded before and after rTMS-MT. Functional connectivity was assessed by phase synchronization index (PSI), and subsequently thresholded to construct undirected graphs in alpha frequency band (8-13 Hz). We found a significant decrease in reaction time after rTMS-MT. The functional connectivity between the parietal and frontal cortex, and the graph theory statistics of node degree and efficiency in the parietal cortex increased. Besides the functional connectivity between premotor and frontal cortex, the degree and efficiency of premotor cortex showed opposite results. In addition, the number of connections significantly increased within inter-hemispheres and inter-regions. In conclusion, this study could be helpful in our understanding of how rTMS-MT modulates brain activity. The methods and results in this study could be taken as reference in future studies of the effects of rTMS-MT in stroke patients.

  19. Single-trial effective brain connectivity patterns enhance discriminability of mental imagery tasks

    Science.gov (United States)

    Rathee, Dheeraj; Cecotti, Hubert; Prasad, Girijesh

    2017-10-01

    Objective. The majority of the current approaches of connectivity based brain-computer interface (BCI) systems focus on distinguishing between different motor imagery (MI) tasks. Brain regions associated with MI are anatomically close to each other, hence these BCI systems suffer from low performances. Our objective is to introduce single-trial connectivity feature based BCI system for cognition imagery (CI) based tasks wherein the associated brain regions are located relatively far away as compared to those for MI. Approach. We implemented time-domain partial Granger causality (PGC) for the estimation of the connectivity features in a BCI setting. The proposed hypothesis has been verified with two publically available datasets involving MI and CI tasks. Main results. The results support the conclusion that connectivity based features can provide a better performance than a classical signal processing framework based on bandpass features coupled with spatial filtering for CI tasks, including word generation, subtraction, and spatial navigation. These results show for the first time that connectivity features can provide a reliable performance for imagery-based BCI system. Significance. We show that single-trial connectivity features for mixed imagery tasks (i.e. combination of CI and MI) can outperform the features obtained by current state-of-the-art method and hence can be successfully applied for BCI applications.

  20. The Potential Development Effect of ASEAN Connectivity: The Case of Riau Corridor

    Directory of Open Access Journals (Sweden)

    Adiwan Aritenang

    2017-12-01

    Full Text Available The Masterplan on ASEAN Connectivity (MPAC presented the ASEAN transportation and connectivity plans to connect the member countries. Despite the clear define objectives, the MPAC implementation remains to be limited. Until 2015, transportation and connectivity projects in Indonesia are scattered in regions without integration under the MPAC scheme. This paper examines the issues and potential role of ASEAN Connectivity implementation in Indonesia. The paper conducts qualitative analysis on literature study, policy content analysis and interviews allowing detail information on the MPAC implementation in Indonesia.  The paper findings are as follows; (i The lack of MPAC implementation at both ASEAN and Indonesia levels. The ASEAN lacks a designated authority and leadership to carry MPAC forward within the member countries, whilst in Indonesia there is no institution to lead the MPAC delivery. (ii The importance role of a leading institution in Indonesia government to define and determine the strategic projects with higher value added. The paper concludes that the national government should regulate and lead the MPAC projects to ensure regional-wide connectivity with ASEAN, whilst at the same time integrate local development in Indonesia.

  1. Effect of connective tissue growth factor (CTGF) expression on radiation pulmonary fibrosis in rats

    International Nuclear Information System (INIS)

    Huang Shanying; Song Liangwen; Zhang Yong; Sun Li; Li Yang

    2005-01-01

    Objective: To explore the effect of connective tissue growth factor (CTGF) on initiation of radiation pulmonary fibrosis (RPF) and the relation to α-smooth muscle actin (α-SMA). Methods: The promotive effect of CTGF on proliferation of human lung fibroblasts (HLF) by 5 Gy of 60 Co γ-rays was determined by MTT colorimetry. The expressions of CTGF and α-SMA in HLF were observed by Western blot. Changes of collagen I and III in rat lungs were determined by Sirius red staining and polarization microscopy. Expressions of CTGF and α-SMA in RPF were observed with immunohisto-chemistry and analysis. Results: Expressions of CTGF and α-SMA were increased. CTGF reached its peak at 24 h after irradiation, whereas α-SMA still kept at a high level 72 h after irradiation. A small amount of collagen was produced in rat lung one month after irradiation, in which type III collagen was the primary component. However, a large amount of collagen was produced in rat lung 3-6 months after irradiation, in which type I was dominant. CTGF began to expression 1 week after irradiation in proliferative fibroblasts of rat lung, and it was most evident 3 months after irradiation. α-SMA began to express in proliferative myofibroblasts 1 week after irradiation, and the high peek was reached at 3 months after irradiation. Conclusion: Irradiation can induce expression of CTGF in pulmonary tissue and the later can promote the transformation of fibroblasts to myofibroblasts, strengthen the ability of synthesis and secretion of type I and III collagen. (authors)

  2. Age-related difference in the effective neural connectivity associated with probabilistic category learning

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Eun Jin; Cho, Sang Soo; Kim, Hee Jung; Bang, Seong Ae; Park, Hyun Soo; Kim, Yu Kyeong; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Although it is well known that explicit memory is affected by the deleterious changes in brain with aging, but effect of aging in implicit memory such as probabilistic category learning (PCL) is not clear. To identify the effect of aging on the neural interaction for successful PCL, we investigated the neural substrates of PCL and the age-related changes of the neural network between these brain regions. 23 young (age, 252 y; 11 males) and 14 elderly (673 y; 7 males) healthy subjects underwent FDG PET during a resting state and 150-trial weather prediction (WP) task. Correlations between the WP hit rates and regional glucose metabolism were assessed using SPM2 (P<0.05 uncorrected). For path analysis, seven brain regions (bilateral middle frontal gyri and putamen, left fusiform gyrus, anterior cingulate and right parahippocampal gyri) were selected based on the results of the correlation analysis. Model construction and path analysis processing were done by AMOS 5.0. The elderly had significantly lower total hit rates than the young (P<0.005). In the correlation analysis, both groups showed similar metabolic correlation in frontal and striatal area. But correlation in the medial temporal lobe (MTL) was found differently by group. In path analysis, the functional networks for the constructed model was accepted (X(2) =0.80, P=0.67) and it proved to be significantly different between groups (X{sub diff}(37) = 142.47, P<0.005), Systematic comparisons of each path revealed that frontal crosscallosal and the frontal to parahippocampal connection were most responsible for the model differences (P<0.05). For the successful PCL, the elderly recruits the basal ganglia implicit memory system but MTL recruitment differs from the young. The inadequate MTL correlation pattern in the elderly is may be caused by the changes of the neural pathway related with explicit memory. These neural changes can explain the decreased performance of PCL in elderly subjects.

  3. Effect of evaluation threat on procrastination behavior.

    Science.gov (United States)

    Bui, Ngoc H

    2007-06-01

    The author evaluated the effects of evaluation apprehension and trait procrastination on behaviors. The author examined private university students from southern California (N = 72) on two independent variables: evaluation threat (manipulated) and trait procrastination (nonmanipulated). The author found a significant interaction effect between type of evaluation threat and level of trait procrastination on the number of days to complete an assigned essay. Post hoc analyses showed high trait procrastinators in the high evaluation threat group significantly delayed returning essays compared with those in the low evaluation threat group. Also, in the low evaluation threat group, low trait procrastinators delayed more than did high trait procrastinators. These results suggest that educators can reduce behavioral delays by increasing evaluation threat, depending on a student's level of trait procrastination.

  4. Identification of the Most Effective Point of Connection for Battery Energy Storage Systems Focusing on Power System Frequency Response Improvement

    Directory of Open Access Journals (Sweden)

    Thiago Pieroni

    2018-03-01

    Full Text Available With the massive penetration of intermittent generation (wind and solar, the reduction of Electrical Power Systems’ (EPSs inertial frequency response represents a new challenge. One alternative to deal with this scenario may be the application of a Battery Energy Storage System (BESS. However, the main constraint for the massive deployment of BESSs is the high acquisition cost of these storage systems which in some situations, can preclude their use in transmission systems. The main goal of this paper is to propose a systematic procedure to include BESSs in power system aiming to improve the power system frequency response using full linear models and geometric measures. In this work, a generic battery model is developed in a two-area test system with assumed high wind penetration and full conventional generators models. The full power system is linearized, and the geometric measures of controllability associated with of the frequency regulation mode are estimated. Then, these results are used to identify the most effective point of connection for a BESS aiming at the improvement of the power system frequency response. Nonlinear time-domain simulations are carried out to evaluate and validate the results.

  5. Maintainability effectiveness evaluations and enhancement

    International Nuclear Information System (INIS)

    Seminara, J.L.

    1985-01-01

    In the mid-seventies EPRI initiated a research project to review the human factors aspects of nuclear power plant control rooms. In the course of investigating operator-control room interfaces in five operational control rooms, it became evident that many plant outages had either been caused or prolonged by human factors problems associated with maintenance activities. Consequently, as one of several follow-on projects, EPRI sponsored a review of nine power plants (five nuclear and four fossil) to examine the human factors aspects of plant maintainability. This survey revealed a wide variety of generic human factors problems that could negatively impact the effectiveness of plant maintenance personnel. It was clear that plant maintainability features deserved no less attention to human factors concerns than the operational features of the control room. This paper describes subsequent EPRI-initiated efforts to assist the utilities in conducting self-reviews of maintainability effectiveness and effect needed enhancements

  6. Effect of mid-thickness rebar mesh on the behavior and punching shear strength of interior slab–column connection

    Directory of Open Access Journals (Sweden)

    Ahmed Ibrahim

    2016-12-01

    The obtained results indicate that, the proposed shear reinforcement system has a positive effect in the enhancement of both the punching shear capacity and the strain energy of interior slab–column connection of both normal and high strength concrete. The general finite element software ANSYS can be used successfully to simulate the punching shear behavior of reinforced concrete flat plates.

  7. 26 CFR 1.1446-2 - Determining a partnership's effectively connected taxable income allocable to foreign partners...

    Science.gov (United States)

    2010-04-01

    ... section 754 (see § 1.743-1(j)). The character of effectively connected partnership items (capital versus... of a partner's basis in the partnership, see section 704(d)) or any capital loss carrybacks or... A's allocable share of partnership ECTI, the amount of the long-term capital loss that may be taken...

  8. Learning Networks: connecting people, organizations, autonomous agents and learning resources to establish the emergence of effective lifelong learning

    NARCIS (Netherlands)

    Koper, Rob; Sloep, Peter

    2003-01-01

    Koper, E.J.R., Sloep, P.B. (2002) Learning Networks connecting people, organizations, autonomous agents and learning resources to establish the emergence of effective lifelong learning. RTD Programma into Learning Technologies 2003-2008. More is different… Heerlen, Nederland: Open Universiteit

  9. 26 CFR 1.937-3 - Income effectively connected with the conduct of a trade or business in a possession.

    Science.gov (United States)

    2010-04-01

    ... operates an active financing business from offices in, Possession I. Interests in G are owned by D, a bona... of a trade or business in a possession. 1.937-3 Section 1.937-3 Internal Revenue INTERNAL REVENUE... United States § 1.937-3 Income effectively connected with the conduct of a trade or business in a...

  10. Effects of ostracism and social connection-related activities on adolescents’ motivation to eat and energy intake

    Science.gov (United States)

    Objective: assess the effect of ostracism and social connection-related activities on adolescents’ motivation to eat and their energy intake. Methods Participants (n¼103; M age¼13.6 years) were either ostracized or included when playing a computer game, Cyberball. Next, they wrote about their friend...

  11. Effect of connective tissue grafting on peri-implant tissue in single immediate implant sites : A RCT

    NARCIS (Netherlands)

    Zuiderveld, Elise G; Meijer, Henny J A; den Hartog, Laurens; Vissink, Arjan; Raghoebar, Gerry M

    AimTo assess the effect of connective tissue grafting on the mid-buccal mucosal level (MBML) of immediately placed and provisionalized single implants in the maxillofacial aesthetic zone. Materials and methodsSixty patients with a failing tooth were provided with an immediately placed and

  12. Children with reading disability show brain differences in effective connectivity for visual, but not auditory word comprehension.

    Directory of Open Access Journals (Sweden)

    Li Liu

    2010-10-01

    Full Text Available Previous literature suggests that those with reading disability (RD have more pronounced deficits during semantic processing in reading as compared to listening comprehension. This discrepancy has been supported by recent neuroimaging studies showing abnormal activity in RD during semantic processing in the visual but not in the auditory modality. Whether effective connectivity between brain regions in RD could also show this pattern of discrepancy has not been investigated.Children (8- to 14-year-olds were given a semantic task in the visual and auditory modality that required an association judgment as to whether two sequentially presented words were associated. Effective connectivity was investigated using Dynamic Causal Modeling (DCM on functional magnetic resonance imaging (fMRI data. Bayesian Model Selection (BMS was used separately for each modality to find a winning family of DCM models separately for typically developing (TD and RD children. BMS yielded the same winning family with modulatory effects on bottom-up connections from the input regions to middle temporal gyrus (MTG and inferior frontal gyrus(IFG with inconclusive evidence regarding top-down modulations. Bayesian Model Averaging (BMA was thus conducted across models in this winning family and compared across groups. The bottom-up effect from the fusiform gyrus (FG to MTG rather than the top-down effect from IFG to MTG was stronger in TD compared to RD for the visual modality. The stronger bottom-up influence in TD was only evident for related word pairs but not for unrelated pairs. No group differences were noted in the auditory modality.This study revealed a modality-specific deficit for children with RD in bottom-up effective connectivity from orthographic to semantic processing regions. There were no group differences in connectivity from frontal regions, suggesting that the core deficit in RD is not in top-down modulation.

  13. An Evaluation of Collagen Metabolism in Non Human Primates Associated with the Bion 11 Space Program-Markers of Urinary Collagen Turnover and Muscle Connective Tissue

    Science.gov (United States)

    Vailas, Arthur C.; Martinez, Daniel A.

    1999-01-01

    Patients exhibiting changes in connective tissue and bone metabolism also show changes in urinary by-products of tissue metabolism. Furthermore, the changes in urinary connective tissue and bone metabolites precede alterations at the tissue macromolecular level. Astronauts and Cosmonauts have also shown suggestive increases in urinary by-products of mineralized and non-mineralized tissue degradation. Thus, the idea of assessing connective tissue and bone response in spaceflight monkeys by measurement of biomarkers in urine has merit. Other investigations of bone and connective histology, cytology and chemistry in the Bion 11 monkeys will allow for further validation of the relationship of urinary biomarkers and tissue response. In future flights the non-invasive procedure of urinary analysis may be useful in early detection of changes in these tissues. The purpose of this grant investigation was to evaluate mineralized and non-mineralized connective tissue responses of non-human primates to microgravity by the non-invasive analysis of urinary biomarkers. Secondly, we also wanted to assess muscle connective tissue adaptive changes in three weight-bearing skeletal muscles: the soleus, media] gastrocnemius and tibialis anterior by obtaining pre-flight and post-flight small biopsy specimens in collaboration with Dr. V. Reggie Edgerton's laboratory at the University of California at Los Angeles.

  14. Role of plain radiography and CT angiography in the evaluation of obstructed total anomalous pulmonary venous connection

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Quanli; Pa, Mier; Hu, Xihong; Wang, Junbo [Children' s Hospital, Fudan University, Department of Radiology, Shanghai (China)

    2013-07-15

    Obstructed total anomalous pulmonary venous connection (TAPVC) is frequently misdiagnosed as pulmonary disease and without operative correction early death is common. It is important to make a correct diagnosis before surgery. The purpose of this study was to describe the chest radiographic features of obstructed TAPVC and compare CT angiography with transthoracic echocardiography in the evaluation of obstructed TAPVC. Eighteen children with obstructed TAPVC were assessed. Their clinical and imaging data were retrospectively reviewed. The characteristic radiographic findings were analyzed and compared with surgical results, and the diagnostic accuracy of CT angiography and transthoracic echocardiography was evaluated in terms of pulmonary venous drainage and obstruction detection. The common radiographic features included pulmonary venous congestion or edema or both (16 of 18 cases, 89%), and absence of cardiomegaly (12 of 18 cases, 67%). CT angiography correctly diagnosed TAPVC and clearly revealed the draining sites in all children (five with supracardiac TAPVC, three with cardiac TAPVC, eight with infracardiac TAPVC and two with mixed TAPVC). The diagnostic agreement between CT angiography and surgery was 100%. Transthoracic echocardiography only correctly revealed the draining sites in 11 children (5 with supracardiac TAPVC, 2 with cardiac TAPVC and 4 with infracardiac TAPVC). The diagnostic agreement between transthoracic echocardiography and surgery was 61%. The diagnostic accuracy of CT angiography was higher than that of transthoracic echocardiography (P = 0.0156). Thirty-four sites of obstruction were correctly detected by CT angiography (11 in the mediastinum, 1 at the diaphragmatic level, 9 below the diaphragm and 13 stenotic individual pulmonary veins in the lung). The diagnostic agreement between CT angiography and surgery was 92%. Transthoracic echocardiography only correctly detected 15 sites of obstruction (11 in the mediastinum, 1 at the

  15. Role of plain radiography and CT angiography in the evaluation of obstructed total anomalous pulmonary venous connection

    International Nuclear Information System (INIS)

    Shen, Quanli; Pa, Mier; Hu, Xihong; Wang, Junbo

    2013-01-01

    Obstructed total anomalous pulmonary venous connection (TAPVC) is frequently misdiagnosed as pulmonary disease and without operative correction early death is common. It is important to make a correct diagnosis before surgery. The purpose of this study was to describe the chest radiographic features of obstructed TAPVC and compare CT angiography with transthoracic echocardiography in the evaluation of obstructed TAPVC. Eighteen children with obstructed TAPVC were assessed. Their clinical and imaging data were retrospectively reviewed. The characteristic radiographic findings were analyzed and compared with surgical results, and the diagnostic accuracy of CT angiography and transthoracic echocardiography was evaluated in terms of pulmonary venous drainage and obstruction detection. The common radiographic features included pulmonary venous congestion or edema or both (16 of 18 cases, 89%), and absence of cardiomegaly (12 of 18 cases, 67%). CT angiography correctly diagnosed TAPVC and clearly revealed the draining sites in all children (five with supracardiac TAPVC, three with cardiac TAPVC, eight with infracardiac TAPVC and two with mixed TAPVC). The diagnostic agreement between CT angiography and surgery was 100%. Transthoracic echocardiography only correctly revealed the draining sites in 11 children (5 with supracardiac TAPVC, 2 with cardiac TAPVC and 4 with infracardiac TAPVC). The diagnostic agreement between transthoracic echocardiography and surgery was 61%. The diagnostic accuracy of CT angiography was higher than that of transthoracic echocardiography (P = 0.0156). Thirty-four sites of obstruction were correctly detected by CT angiography (11 in the mediastinum, 1 at the diaphragmatic level, 9 below the diaphragm and 13 stenotic individual pulmonary veins in the lung). The diagnostic agreement between CT angiography and surgery was 92%. Transthoracic echocardiography only correctly detected 15 sites of obstruction (11 in the mediastinum, 1 at the

  16. Connecting Grammaticalisation

    DEFF Research Database (Denmark)

    Nørgård-Sørensen, Jens; Heltoft, Lars; Schøsler, Lene

    morphological, topological and constructional paradigms often connect to form complex paradigms. The book introduces the concept of connecting grammaticalisation to describe the formation, restructuring and dismantling of such complex paradigms. Drawing primarily on data from Germanic, Romance and Slavic...

  17. Effect of platform connection and abutment material on stress distribution in single anterior implant-supported restorations: a nonlinear 3-dimensional finite element analysis.

    Science.gov (United States)

    Carvalho, Marco Aurélio; Sotto-Maior, Bruno Salles; Del Bel Cury, Altair Antoninha; Pessanha Henriques, Guilherme Elias

    2014-11-01

    Although various abutment connections and materials have recently been introduced, insufficient data exist regarding the effect of stress distribution on their mechanical performance. The purpose of this study was to investigate the effect of different abutment materials and platform connections on stress distribution in single anterior implant-supported restorations with the finite element method. Nine experimental groups were modeled from the combination of 3 platform connections (external hexagon, internal hexagon, and Morse tapered) and 3 abutment materials (titanium, zirconia, and hybrid) as follows: external hexagon-titanium, external hexagon-zirconia, external hexagon-hybrid, internal hexagon-titanium, internal hexagon-zirconia, internal hexagon-hybrid, Morse tapered-titanium, Morse tapered-zirconia, and Morse tapered-hybrid. Finite element models consisted of a 4×13-mm implant, anatomic abutment, and lithium disilicate central incisor crown cemented over the abutment. The 49 N occlusal loading was applied in 6 steps to simulate the incisal guidance. Equivalent von Mises stress (σvM) was used for both the qualitative and quantitative evaluation of the implant and abutment in all the groups and the maximum (σmax) and minimum (σmin) principal stresses for the numerical comparison of the zirconia parts. The highest abutment σvM occurred in the Morse-tapered groups and the lowest in the external hexagon-hybrid, internal hexagon-titanium, and internal hexagon-hybrid groups. The σmax and σmin values were lower in the hybrid groups than in the zirconia groups. The stress distribution concentrated in the abutment-implant interface in all the groups, regardless of the platform connection or abutment material. The platform connection influenced the stress on abutments more than the abutment material. The stress values for implants were similar among different platform connections, but greater stress concentrations were observed in internal connections

  18. The effects of age on resting state functional connectivity of the basal ganglia from young to middle adulthood.

    Science.gov (United States)

    Manza, Peter; Zhang, Sheng; Hu, Sien; Chao, Herta H; Leung, Hoi-Chung; Li, Chiang-Shan R

    2015-02-15

    The basal ganglia nuclei are critical for a variety of cognitive and motor functions. Much work has shown age-related structural changes of the basal ganglia. Yet less is known about how the functional interactions of these regions with the cerebral cortex and the cerebellum change throughout the lifespan. Here, we took advantage of a convenient sample and examined resting state functional magnetic resonance imaging data from 250 adults 18 to 49 years of age, focusing specifically on the caudate nucleus, pallidum, putamen, and ventral tegmental area/substantia nigra (VTA/SN). There are a few main findings to report. First, with age, caudate head connectivity increased with a large region of ventromedial prefrontal/medial orbitofrontal cortex. Second, across all subjects, pallidum and putamen showed negative connectivity with default mode network (DMN) regions such as the ventromedial prefrontal cortex and posterior cingulate cortex, in support of anti-correlation of the "task-positive" network (TPN) and DMN. This negative connectivity was reduced with age. Furthermore, pallidum, posterior putamen and VTA/SN connectivity to other TPN regions, such as somatomotor cortex, decreased with age. These results highlight a distinct effect of age on cerebral functional connectivity of the dorsal striatum and VTA/SN from young to middle adulthood and may help research investigating the etiologies or monitoring outcomes of neuropsychiatric conditions that implicate dopaminergic dysfunction. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. An Index to Measure Effects of a Declining Area of Set-aside Land on Habitat-connectivity in Denmark

    DEFF Research Database (Denmark)

    Levin, Gregor

    2009-01-01

    In Denmark, agriculture occupies 28,000 km² or 65% of the land. As a consequence, habitats for wild species are mainly characterized by small patches, surrounded by intensive agriculture. Due to extensive agricultural management, set-aside land can spatially connect habitats and thus positively...... affect habitat connectivity, which is of importance to the survival of wild species. In 2008 set-aside schemes were abolished, leading to a considerable re-cultivation of former set-aside land and consequently to a decline in the area of set-aside land from 6% of all agricultural land in 2007 to 3...... to natural habitats, would typically not be re-cultivated. I developed an indicator aiming to measure the effect of the reduced area of set-aside land on habitat-connectivity. For a raster-map with a resolution of 25x25 meters, the indicator combines the distance to habitats with the area percentage of set...

  20. Effect of sensory and motor connectivity on hand function in pediatric hemiplegia.

    Science.gov (United States)

    Gupta, Disha; Barachant, Alexandre; Gordon, Andrew M; Ferre, Claudio; Kuo, Hsing-Ching; Carmel, Jason B; Friel, Kathleen M

    2017-11-01

    We tested the hypothesis that somatosensory system injury would more strongly affect movement than motor system injury in children with unilateral cerebral palsy (USCP). This hypothesis was based on how somatosensory and corticospinal circuits adapt to injury during development; whereas the motor system can maintain connections to the impaired hand from the uninjured hemisphere, this does not occur in the somatosensory system. As a corollary, cortical injury strongly impairs sensory function, so we hypothesized that cortical lesions would impair hand function more than subcortical lesions. Twenty-four children with unilateral cerebral palsy had physiological and anatomical measures of the motor and somatosensory systems and lesion classification. Motor physiology was performed with transcranial magnetic stimulation and somatosensory physiology with vibration-evoked electroencephalographic potentials. Tractography of the corticospinal tract and the medial lemniscus was performed with diffusion tensor imaging, and lesions were classified by magnetic resonance imaging. Anatomical and physiological results were correlated with measures of hand function using 2 independent statistical methods. Children with disruptions in the somatosensory connectivity and cortical lesions had the most severe upper extremity impairments, particularly somatosensory function. Motor system connectivity was significantly correlated with bimanual function, but not unimanual function or somatosensory function. Both sensory and motor connectivity impact hand function in children with USCP. Somatosensory connectivity could be an important target for recovery of hand function in children with USCP. Ann Neurol 2017;82:766-780. © 2017 American Neurological Association.

  1. Single-Tooth Morse Taper Connection Implant Placed in Grafted Site of the Anterior Maxilla: Clinical and Radiographic Evaluation

    Directory of Open Access Journals (Sweden)

    Francesco Guido Mangano

    2014-01-01

    Full Text Available The aim of this study was to achieve aesthetically pleasing soft tissue contours in a severely compromised tooth in the anterior region of the maxilla. For a right-maxillary central incisor with localized advanced chronic periodontitis a tooth extraction followed by reconstructive procedures and delayed implant placement was proposed and accepted by the patient. Guided bone regeneration (GBR technique was employed, with a biphasic calcium-phosphate (BCP block graft placed in the extraction socket in conjunction with granules of the same material and a resorbable barrier membrane. After 6 months of healing, an implant was installed. The acrylic provisional restoration remained in situ for 3 months and then was substituted with the definitive crown. This ridge reconstruction technique enabled preserving both hard and soft tissues and counteracting vertical and horizontal bone resorption after tooth extraction and allowed for an ideal three-dimensional implant placement. Localized severe alveolar bone resorption of the anterior maxilla associated with chronic periodontal disease can be successfully treated by means of ridge reconstruction with GBR and delayed implant insertion; the placement of an early-loaded, Morse taper connection implant in the grafted site was effective to create an excellent clinical aesthetic result and to maintain it along time.

  2. Effective Connectivity within the Default Mode Network: Dynamic Causal Modeling of Resting-State fMRI Data.

    Science.gov (United States)

    Sharaev, Maksim G; Zavyalova, Viktoria V; Ushakov, Vadim L; Kartashov, Sergey I; Velichkovsky, Boris M

    2016-01-01

    The Default Mode Network (DMN) is a brain system that mediates internal modes of cognitive activity, showing higher neural activation when one is at rest. Nowadays, there is a lot of interest in assessing functional interactions between its key regions, but in the majority of studies only association of Blood-oxygen-level dependent (BOLD) activation patterns is measured, so it is impossible to identify causal influences. There are some studies of causal interactions (i.e., effective connectivity), however often with inconsistent results. The aim of the current work is to find a stable pattern of connectivity between four DMN key regions: the medial prefrontal cortex (mPFC), the posterior cingulate cortex (PCC), left and right intraparietal cortex (LIPC and RIPC). For this purpose functional magnetic resonance imaging (fMRI) data from 30 healthy subjects (1000 time points from each one) was acquired and spectral dynamic causal modeling (DCM) on a resting-state fMRI data was performed. The endogenous brain fluctuations were explicitly modeled by Discrete Cosine Set at the low frequency band of 0.0078-0.1 Hz. The best model at the group level is the one where connections from both bilateral IPC to mPFC and PCC are significant and symmetrical in strength (p bidirectional, significant in the group and weaker than connections originating from bilateral IPC. In general, all connections from LIPC/RIPC to other DMN regions are much stronger. One can assume that these regions have a driving role within the DMN. Our results replicate some data from earlier works on effective connectivity within the DMN as well as provide new insights on internal DMN relationships and brain's functioning at resting state.

  3. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape.

    Science.gov (United States)

    Pilliod, David S; Arkle, Robert S; Robertson, Jeanne M; Murphy, Melanie A; Funk, W Chris

    2015-09-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900-1930), recent (1981-2010), and future (2071-2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May - September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50-80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

  4. Effects of changing climate on aquatic habitat and connectivity for remnant populations of a wide-ranging frog species in an arid landscape

    Science.gov (United States)

    Pilliod, David S.; Arkle, Robert S.; Robertson, Jeanne M; Murphy, Melanie; Funk, W. Chris

    2015-01-01

    Amphibian species persisting in isolated streams and wetlands in desert environments can be susceptible to low connectivity, genetic isolation, and climate changes. We evaluated the past (1900–1930), recent (1981–2010), and future (2071–2100) climate suitability of the arid Great Basin (USA) for the Columbia spotted frog (Rana luteiventris) and assessed whether changes in surface water may affect connectivity for remaining populations. We developed a predictive model of current climate suitability and used it to predict the historic and future distribution of suitable climates. We then modeled changes in surface water availability at each time period. Finally, we quantified connectivity among existing populations on the basis of hydrology and correlated it with interpopulation genetic distance. We found that the area of the Great Basin with suitable climate conditions has declined by approximately 49% over the last century and will likely continue to decline under future climate scenarios. Climate conditions at currently occupied locations have been relatively stable over the last century, which may explain persistence at these sites. However, future climates at these currently occupied locations are predicted to become warmer throughout the year and drier during the frog's activity period (May – September). Fall and winter precipitation may increase, but as rain instead of snow. Earlier runoff and lower summer base flows may reduce connectivity between neighboring populations, which is already limited. Many of these changes could have negative effects on remaining populations over the next 50–80 years, but milder winters, longer growing seasons, and wetter falls might positively affect survival and dispersal. Collectively, however, seasonal shifts in temperature, precipitation, and stream flow patterns could reduce habitat suitability and connectivity for frogs and possibly other aquatic species inhabiting streams in this arid region.

  5. Distinctive Structural and Effective Connectivity Changes of Semantic Cognition Network across Left and Right Mesial Temporal Lobe Epilepsy Patients

    Directory of Open Access Journals (Sweden)

    Xiaotong Fan

    2016-01-01

    Full Text Available Occurrence of language impairment in mesial temporal lobe epilepsy (mTLE patients is common and left mTLE patients always exhibit a primary problem with access to names. To explore different neuropsychological profiles between left and right mTLE patients, the study investigated both structural and effective functional connectivity changes within the semantic cognition network between these two groups and those from normal controls. We found that gray matter atrophy of left mTLE patients was more severe than that of right mTLE patients in the whole brain and especially within the semantic cognition network in their contralateral hemisphere. It suggested that seizure attacks were rather targeted than random for patients with hippocampal sclerosis (HS in the dominant hemisphere. Functional connectivity analysis during resting state fMRI revealed that subregions of the anterior temporal lobe (ATL in the left HS patients were no longer effectively connected. Further, we found that, unlike in right HS patients, increased causal linking between ipsilateral regions in the left HS epilepsy patients cannot make up for their decreased contralateral interaction. It suggested that weakened contralateral connection and disrupted effective interaction between subregions of the unitary, transmodal hub of the ATL may be the primary cause of anomia in the left HS patients.

  6. Distinctive Structural and Effective Connectivity Changes of Semantic Cognition Network across Left and Right Mesial Temporal Lobe Epilepsy Patients

    Science.gov (United States)

    Fan, Xiaotong; Shang, Kun; Wang, Xiaocui; Wang, Peipei; Shan, Yongzhi; Lu, Jie

    2016-01-01

    Occurrence of language impairment in mesial temporal lobe epilepsy (mTLE) patients is common and left mTLE patients always exhibit a primary problem with access to names. To explore different neuropsychological profiles between left and right mTLE patients, the study investigated both structural and effective functional connectivity changes within the semantic cognition network between these two groups and those from normal controls. We found that gray matter atrophy of left mTLE patients was more severe than that of right mTLE patients in the whole brain and especially within the semantic cognition network in their contralateral hemisphere. It suggested that seizure attacks were rather targeted than random for patients with hippocampal sclerosis (HS) in the dominant hemisphere. Functional connectivity analysis during resting state fMRI revealed that subregions of the anterior temporal lobe (ATL) in the left HS patients were no longer effectively connected. Further, we found that, unlike in right HS patients, increased causal linking between ipsilateral regions in the left HS epilepsy patients cannot make up for their decreased contralateral interaction. It suggested that weakened contralateral connection and disrupted effective interaction between subregions of the unitary, transmodal hub of the ATL may be the primary cause of anomia in the left HS patients. PMID:28018680

  7. Investigating the Impact of Shading Effect on the Characteristics of a Large-Scale Grid-Connected PV Power Plant in Northwest China

    Directory of Open Access Journals (Sweden)

    Yunlin Sun

    2014-01-01

    Full Text Available Northwest China is an ideal region for large-scale grid-connected PV system installation due to its abundant solar radiation and vast areas. For grid-connected PV systems in this region, one of the key issues is how to reduce the shading effect as much as possible to maximize their power generation. In this paper, a shading simulation model for PV modules is established and its reliability is verified under the standard testing condition (STC in laboratory. Based on the investigation result of a 20 MWp grid-connected PV plant in northwest China, the typical shading phenomena are classified and analyzed individually, such as power distribution buildings shading and wire poles shading, plants and birds droppings shading, and front-row PV arrays shading. A series of experiments is also conducted on-site to evaluate and compare the impacts of different typical shading forms. Finally, some feasible solutions are proposed to avoid or reduce the shading effect of PV system during operation in such region.

  8. Comparative evaluation of a bioabsorbable collagen membrane and connective tissue graft in the treatment of localized gingival recession: A clinical study

    Directory of Open Access Journals (Sweden)

    Harsha Mysore Babu

    2011-01-01

    Full Text Available Background: Gingival recession (GR can result in root sensitivity, esthetic concern to the patient, and predilection to root caries. The purpose of this randomized clinical study was to evaluate (1 the effect of guided tissue regeneration (GTR procedure using a bioabsorbable collagen membrane, in comparison to autogenous subepithelial connective tissue graft (SCTG for root coverage in localized gingival recession defects; and (2 the change in width of keratinized gingiva following these two procedures. Materials and Methods: A total of 10 cases, showing at least two localized Miller′s Class I or Class II gingival recession, participated in this study. In a split mouth design, the pairs of defects were randomly assigned for treatment with either SCTG (SCTG Group or GTR-based collagen membrane (GTRC Group. Both the grafts were covered with coronally advanced flap. Recession depth (RD, recession width (RW, width of keratinized gingiva (KG, probing depth (PD, relative attachment level (RAL, plaque index (PI, and gingival index (GI were recorded at baseline, 3 and 6 months postoperatively. Results: Six months following root coverage procedures, the mean root coverage was found to be 84.84% ± 16.81% and 84.0% ± 15.19% in SCTG Group and GTRC Group, respectively. The mean keratinized gingival width increase was 1.50 ± 0.70 mm and 2.30 ± 0.67 mm in the SCTG and GTRC group, respectively, which was not statistically significant. Conclusion: It may be concluded that resorbable collagen membrane can be a reliable alternative to autogenous connective tissue graft in the treatment of gingival recession.

  9. Evaluating a steel beam’s rigid connection to a concrete filled tubular column when submitted to dynamic load

    Directory of Open Access Journals (Sweden)

    Maritza Uribe Vallejo

    2009-01-01

    Full Text Available Using prequalified connections during the structural design stage becomes increasingly necessary when developing structural en-gineering projects which include steel elements; this is so that the steel elements’ appropriate behavior can be ensured according to the structural system and seismic demand. Unfortunately, the international entities providing this type of information (i.e. FEMA only have a limit series of prequalified connections and such series do not include rigid connections between steel beams and concrete filled tubular (CFT columns having an extended end plate, which has become a very widespread building practice in Colombia. This paper describes the most important aspects of a study at the Universidad Nacional de Colombia concerning the behavior of a steel beam rigidly connected to a CFT-column, using six physical models having different width-thickness ratio (b/t columns. ANSYS v.10 software was used for studying theoretical models (finite elements analysis for comparative analysis of cyclic test theoretical and experimental results for each specimen presented for the qualification phase. The six tested specimens’ hysteretic curves are presented. Several conclusions are drawn concerning finite element validation for this type of connection and the influence of width-thickness ratio (b/t variation and design recommendations for suitable behavior under dynamic loads when this type of connection was used.

  10. Evaluation of an interprofessional education program for advanced practice nursing and dental students: The oral-systemic health connection.

    Science.gov (United States)

    Nash, Whitney A; Hall, Lynne A; Lee Ridner, S; Hayden, Dedra; Mayfield, Theresa; Firriolo, John; Hupp, Wendy; Weathers, Chandra; Crawford, Timothy N

    2018-03-27

    In response to the growing body of evidence supporting the need for expanded interprofessional education among health professions, an interprofessional education program, based on the Interprofessional Education Collaborative Core Competencies, was piloted with nurse practitioner and dental students. The purpose of this pilot study was to evaluate a technology enhanced interprofessional education program focused on the oral-systemic health connection for nurse practitioner and dental students. A two-group comparative study using cross-sectional data and a quasi-experimental one-group pre-test/post-test design were used to evaluate students' knowledge of IPE core competencies, attitudes toward interprofessional education and interdisciplinary teamwork, and self-efficacy in functioning as a member of an interdisciplinary team. This program was implemented with master of science in nursing students pursuing a primary care nurse practitioner (NP) degree and dental students at a large urban academic health sciences center. Cohort 1 (N = 75) consisted of NP (n = 34) and dental students (n = 41) at the end of their degree program who participated in a one-time survey. Cohort 2 (N = 116) was comprised of second-year NP students (n = 22) and first-year dental students (n = 94) who participated in the IPE program. Students participated in a multi-faceted educational program consisting of technology- enhanced delivery as well as interactive exercises in the joint health assessment course. Data were collected prior to the initiation and at the conclusion of the program. Nurse practitioner and dental students who participated in the program had better self-efficacy in functioning as a member of an interdisciplinary team than graduating students who did not participate. Students from both nursing and dentistry who participated in the program had significantly improved self-efficacy in functioning in interprofessional teams from pre- to post-test. An

  11. Evaluation of training effectiveness in Cez, a.s

    International Nuclear Information System (INIS)

    Svejda, B.; Kopecny, J.

    2003-01-01

    Nuclear power plant personnel training is realised by the way of basic and periodical training forms within the framework of Czech power company CEZ1. What concerning of contractors, the similar forms of personnel training are used, too. Goals and scope of the training are defined unambiguously - all training process executes according to prepared training programmes. For each profession category exists a comprehensive complete of training programmes covering all forms of personnel training. Thus, evaluation of the training programmes is closely connected with information about effectiveness of training. On the basis of these facts is possible to improve all the training process continuously. The basic information about training centre, some results of the programme training evaluation using method of characteristic indicators and information about its present status in NPP Dukovany are provided in first part of this paper. In the Appendix is described used procedure of feedback to analysis phase to improve content of training process for job position 'turbine repair man'. (author)

  12. Effect of MELT method on thoracolumbar connective tissue: The full study.

    Science.gov (United States)

    Sanjana, Faria; Chaudhry, Hans; Findley, Thomas

    2017-01-01

    Altered connective tissue structure has been identified in adults with chronic low back pain (LBP). A self-care treatment for managing LBP is the MELT method. The MELT method is a hands-off, self-treatment that is said to alleviate chronic pain, release tension and restore mobility, utilizing specialized soft treatments balls, soft body roller and techniques mimicking manual therapy. The objective of this study was to determine whether thickness of thoracolumbar connective tissue and biomechanical and viscoelastic properties of myofascial tissue in the low back region change in subjects with chronic LBP as a result of MELT. This study was designed using a quasi experimental pre-post- design that analyzed data from subjects who performed MELT. Using ultrasound imaging and an algorithm developed in MATLAB, thickness of thoracolumbar connective tissue was analyzed in 22 subjects. A hand-held digital palpation device, called the MyotonPRO, was used to assess biomechanical properties such as stiffness, elasticity, tone and mechanical stress relaxation time of the thoracolumbar myofascial tissue. A forward bending test assessing flexibility and pain scale was added to see if MELT affected subjects with chronic LBP. A significant decrease in connective tissue thickness and pain was observed in participants. Significant increase in flexibility was also recorded. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Effect of Long-Term Cannabis Use on Axonal Fibre Connectivity

    Science.gov (United States)

    Zalesky, Andrew; Solowij, Nadia; Yucel, Murat; Lubman, Dan I.; Takagi, Michael; Harding, Ian H.; Lorenzetti, Valentina; Wang, Ruopeng; Searle, Karissa; Pantelis, Christos; Seal, Marc

    2012-01-01

    Cannabis use typically begins during adolescence and early adulthood, a period when cannabinoid receptors are still abundant in white matter pathways across the brain. However, few studies to date have explored the impact of regular cannabis use on white matter structure, with no previous studies examining its impact on axonal connectivity. The…

  14. Effects of exercise and respiration on blood flow in total cavopulmonary connection

    DEFF Research Database (Denmark)

    Hjortdal, V E; Emmertsen, K; Stenbøg, E

    2003-01-01

    BACKGROUND: Little is known about blood flow and its relationship to respiration during exercise in patients with total cavopulmonary connection (TCPC). METHODS AND RESULTS: We studied 11 patients 12.4+/-4.6 years (mean+/-SD) of age 5.9+/-2.8 years (mean+/-SD) after TCPC operation. Real-time MRI...

  15. Differences in atypical resting-state effective connectivity distinguish autism from schizophrenia

    Directory of Open Access Journals (Sweden)

    Dana Mastrovito

    Full Text Available Autism and schizophrenia share overlapping genetic etiology, common changes in brain structure and common cognitive deficits. A number of studies using resting state fMRI have shown that machine learning algorithms can distinguish between healthy controls and individuals diagnosed with either autism spectrum disorder or schizophrenia. However, it has not yet been determined whether machine learning algorithms can be used to distinguish between the two disorders. Using a linear support vector machine, we identify features that are most diagnostic for each disorder and successfully use them to classify an independent cohort of subjects. We find both common and divergent connectivity differences largely in the default mode network as well as in salience, and motor networks. Using divergent connectivity differences, we are able to distinguish autistic subjects from those with schizophrenia. Understanding the common and divergent connectivity changes associated with these disorders may provide a framework for understanding their shared cognitive deficits. Keywords: Schizophrenia, Autism, Resting state, Classification, Connectivity, fMRI, Default mode network

  16. Small words, big effects? Subjective versus objective causal connectives in discourse processing

    NARCIS (Netherlands)

    Canestrelli, A.R.

    2013-01-01

    Coherence relations and their linguistic markers play a significant role in the study of discourse processing and comprehension. A number of studies have shown that the presence of coherence markers, such as connectives, in a text facilitates the processing and representation of discourse.

  17. Effect of DEM resolution and comparison between different weighting factors for hydrologic connectivity index

    Science.gov (United States)

    Cantreul, Vincent; Cavalli, Marco; Degré, Aurore

    2016-04-01

    The emerging concept of hydrological connectivity is difficult to quantify. Some indices have been proposed. The most cited is Borselli's one. It mainly uses the DEM as input. The pixel size may strongly impacts the result of the calculation. It has not been studied yet in silty areas. Another important aspect is the choice of the weighting factor which strongly influences the index value. The objective of this poster is so to compare 8 different DEM's resolutions (12, 24, 48, 72, 96, 204, 504 and 996cm) and 3 different weighting factors (factor C of Wischmeier, Manning's factor and rugosity index) in the Borselli's index calculation. The IC was calculated in a 124ha catchment (Hevillers), in the loess belt, in Belgium. The DEM used is coming from a UAV with a maximum resolution of 12 cm. Permanent covered surfaces are not considered in order to avoid artefact due to the vegetation (2% of the surface). Regarding the DEM pixel size, the IC increases for a given pixel when the pixel size decreases. That confirms some results observed in the Alpine region by Cavalli (2014). The mean difference between 12 cm and 10 m resolution is 35% with higher values up to 100% for higher connectivity zones (flow paths). Another result is the lower impact of connections in the watershed (grass strips…) at lower pixel sizes. This is linked to the small width of some connections which are sometimes comparing to cell size. Furthermore, a great loss of precision is observed from the 500 cm pixel size and upper. That remark is quite intuitive. Finally, some very well disconnected zones appear for the highest resolutions. Regarding the weighting factor, IC values calculated using C factor are lower than with the rugosity index which is only a topographic factor. With very high resolution DEM, it permits to represent the fine topography. For the C factor, the zones up to very well disconnected areas (grass strips, wood…) are well represented with lower index values than downstream

  18. Effect of electrocardiogram interference on cortico-cortical connectivity analysis and a possible solution.

    Science.gov (United States)

    Govindan, R B; Kota, Srinivas; Al-Shargabi, Tareq; Massaro, An N; Chang, Taeun; du Plessis, Adre

    2016-09-01

    Electroencephalogram (EEG) signals are often contaminated by the electrocardiogram (ECG) interference, which affects quantitative characterization of EEG. We propose null-coherence, a frequency-based approach, to attenuate the ECG interference in EEG using simultaneously recorded ECG as a reference signal. After validating the proposed approach using numerically simulated data, we apply this approach to EEG recorded from six newborns receiving therapeutic hypothermia for neonatal encephalopathy. We compare our approach with an independent component analysis (ICA), a previously proposed approach to attenuate ECG artifacts in the EEG signal. The power spectrum and the cortico-cortical connectivity of the ECG attenuated EEG was compared against the power spectrum and the cortico-cortical connectivity of the raw EEG. The null-coherence approach attenuated the ECG contamination without leaving any residual of the ECG in the EEG. We show that the null-coherence approach performs better than ICA in attenuating the ECG contamination without enhancing cortico-cortical connectivity. Our analysis suggests that using ICA to remove ECG contamination from the EEG suffers from redistribution problems, whereas the null-coherence approach does not. We show that both the null-coherence and ICA approaches attenuate the ECG contamination. However, the EEG obtained after ICA cleaning displayed higher cortico-cortical connectivity compared with that obtained using the null-coherence approach. This suggests that null-coherence is superior to ICA in attenuating the ECG interference in EEG for cortico-cortical connectivity analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Effective Connectivity from Early Visual Cortex to Posterior Occipitotemporal Face Areas Supports Face Selectivity and Predicts Developmental Prosopagnosia.

    Science.gov (United States)

    Lohse, Michael; Garrido, Lucia; Driver, Jon; Dolan, Raymond J; Duchaine, Bradley C; Furl, Nicholas

    2016-03-30

    Face processing is mediated by interactions between functional areas in the occipital and temporal lobe, and the fusiform face area (FFA) and anterior temporal lobe play key roles in the recognition of facial identity. Individuals with developmental prosopagnosia (DP), a lifelong face recognition impairment, have been shown to have structural and functional neuronal alterations in these areas. The present study investigated how face selectivity is generated in participants with normal face processing, and how functional abnormalities associated with DP, arise as a function of network connectivity. Using functional magnetic resonance imaging and dynamic causal modeling, we examined effective connectivity in normal participants by assessing network models that include early visual cortex (EVC) and face-selective areas and then investigated the integrity of this connectivity in participants with DP. Results showed that a feedforward architecture from EVC to the occipital face area, EVC to FFA, and EVC to posterior superior temporal sulcus (pSTS) best explained how face selectivity arises in both controls and participants with DP. In this architecture, the DP group showed reduced connection strengths on feedforward connections carrying face information from EVC to FFA and EVC to pSTS. These altered network dynamics in DP contribute to the diminished face selectivity in the posterior occipitotemporal areas affected in DP. These findings suggest a novel view on the relevance of feedforward projection from EVC to posterior occipitotemporal face areas in generating cortical face selectivity and differences in face recognition ability. Areas of the human brain showing enhanced activation to faces compared to other objects or places have been extensively studied. However, the factors leading to this face selectively have remained mostly unknown. We show that effective connectivity from early visual cortex to posterior occipitotemporal face areas gives rise to face

  20. Activation and integration are not the same: Changing effective connectivity in recovery from acute aphasia

    Directory of Open Access Journals (Sweden)

    David W Gow

    2014-04-01

    Full Text Available The relationship between BOLD activation and processing in recovering aphasics is complex. Patterns of shifting upregulation of perilesional and contralesional task-related BOLD response have been widely observed in patients during subacute and chronic phases of recovery (c.f. Saur et al., 2006. However, a number of studies have found a relatively weak relationship between these changes and performance in language tasks (e.g. Heiss et al., 1999; Cornelissen et al., 2003. In this work, we explore the evolving relationship between activation and effective connectivity in a patient with aphasia. The patient, a 53 year old left handed woman, presented with frequent phonemic paraphasias and word-finding difficulty following a patchy right-hemispheric ischemic stroke affecting the temporo-parietal region, basal ganglia, and portions of occipital cortex. These results suggest she showed right hemisphere linguistic dominance premorbidly. Screening using the PAL (Caplan& Bub, 1990 revealed deficits in phoneme discrimination and auditory word-picture matching with preserved auditory lexical decision. She was tested twice on a go/no-go auditory word picture matching task one month post-onset, and again six months later while simultaneous MEG and EEG data were acquired. She achieved 59% accuracy at the initial testing, and 85% accuracy on retest. Source space reconstructions of activity between 100-400 msec after the onset of the spoken word (before the visual probe stimulus showed strong perilesional activation with moderate activation of left hemisphere language areas. When tested 6 months later perilesional activation was significantly reduced, but left hemisphere activation was stronger. Kalman-filter enabled Granger analyses (Gow & Caplan, 2012 of the same MR-constrained MEG/EEG data showed little evidence of interaction or either intra- or interhemispheric interactions between activated regions at one month post onset. At seven months, the network

  1. THE PRIMACY EFFECT IN AMNESTIC MILD COGNITIVE IMPAIRMENT: ASSOCIATIONS WITH HIPPOCAMPAL FUNCTIONAL CONNECTIVITY

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    Katharina Brueggen

    2016-10-01

    Full Text Available BackgroundThe primacy effect, i.e., increased memory recall for the first items of a series compared to the following items, is reduced in amnestic mild cognitive impairment (aMCI. Memory task-fMRI studies showed that primacy recall is associated with higher activation of the hippocampus and temporo-parietal and frontal cortical regions in healthy subjects. Functional magnetic resonance imaging (fMRI at resting state showed that hippocampus functional connectivity (FC with neocortical brain areas, including regions of the default mode network (DMN, is altered in aMCI. The present study aimed to investigate whether resting state fMRI FC between the hippocampus and cortical brain regions, especially the DMN, is associated with primacy recall performance in aMCI. MethodsA number of 87 aMCI patients underwent resting state fMRI and verbal episodic memory assessment. FC between the left or right hippocampus, respectively, and all other voxels in grey matter was mapped voxel-wise and used in whole-brain regression analyses, testing whether FC values predicted delayed primacy recall score. The delayed primacy score was defined as the number of the first four words recalled on the California Verbal Learning Test. Additionally, a partial least squares analysis (PLS was performed, using DMN regions as seeds to identify the association of their functional interactions with delayed primacy recall.ResultsVoxel-based analyses showed that delayed primacy recall was mainly (positively associated with higher FC between the left and right hippocampus. Additionally, significant associations were found for higher FC between the left hippocampus and bilateral temporal cortex, frontal cortical regions, and for higher FC between the right hippocampus and right temporal cortex, right frontal cortical regions, left medial frontal cortex and right amygdala (p < 0.01, uncorr.. PLS analysis revealed positive associations of delayed primacy recall with FC between regions of

  2. Design and Analytical Evaluation of a New Self-Centering Connection with Bolted T-Stub Devices

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    Mahbobeh Mirzaie Aliabadi

    2013-01-01

    Full Text Available A new posttensioned T-stub connection (PTTC for earthquake resistant steel moment resisting frames (MRFs is introduced. The proposed connection consists of high strength posttensioned (PT strands and bolted T-stubs. The post-tensioning strands run through the column and are anchored against the flange of the exterior column. The T-stubs, providing energy dissipation, are bolted to the flange of beam and column and no field welding is required. The strands compress the T-stub against the column flange to develop the resisting moment to service loads and to provide a restoring force that returns the structure to its initial position following an earthquake. An analytical model based on fiber elements is developed in OpenSees to model PTTCs. The analytical model can predict the expected behavior of the new proposed connection under cyclic loading. PTTC provides similar characteristic behavior of the posttensioned connections. Both theoretical behavior and design methods are proposed, and the design methods are verified based on parametric studies and comparison to analytical results. The parametric studies prove the desired self-centering behavior of PTTC and show that this connection can reduce or eliminate the plastic rotation by its self-centering behavior as well as providing required strength and stiffness under large earthquake rotations.

  3. Evaluating the Effectiveness Of Postfire Rehabilitation Treatments

    Science.gov (United States)

    Peter R. Robichaud; Jan L. Beyers; Daniel G. Neary

    2000-01-01

    Spending on postfire emergency watershed rehabilitation has increased during the past decade. A west-wide evaluation of USDA Forest Service burned area emergency rehabilitation (BAER) treatment effectiveness was undertaken as a joint project by USDA Forest Service Research and National Forest System staffs. This evaluation covers 470 fires and 321 BAER projects, from...

  4. Dynamic causal modeling of hippocampal links within the human default mode network: Lateralization and computational stability of effective connections

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    Vadim Leonidovich Ushakov

    2016-10-01

    Full Text Available The purpose of this paper was to study causal relationships between left and right hippocampal regions (LHIP and RHIP, respectively within the default mode network (DMN as represented by its key structures: the medial prefrontal cortex (MPFC, posterior cingulate cortex (PCC and the inferior parietal cortex of left (LIPC and right (RIPC hemispheres. Furthermore, we were interested in testing the stability of the connectivity patterns when adding or deleting regions of interest. The functional magnetic resonance imaging (fMRI data from a group of 30 healthy right-handed subjects in the resting state were collected and a connectivity analysis was performed. To model the effective connectivity, we used the spectral Dynamic Causal Modeling (DCM. Three DCM analyses were completed. Two of them modeled interaction between five nodes that included four DMN key structures in addition to either LHIP or RHIP. The last DCM analysis modeled interactions between four nodes whereby one of the main DMN structures, PCC, was excluded from the analysis. The results of all DCM analyses indicated a high level of stability in the computational method: those parts of the winning models that included the key DMN structures demonstrated causal relations known from recent research. However, we discovered new results as well. First of all, we found a pronounced asymmetry in LHIP and RHIP connections. LHIP demonstrated a high involvement of DMN activity with preponderant information outflow to all other DMN regions. Causal interactions of LHIP were bidirectional only in the case of LIPC. On the contrary, RHIP was primarily affected by inputs from LIPC, RIPC and LHIP without influencing these or other DMN key structures. For the first time, an inhibitory link was found from MPFC to LIPC, which may indicate the subjects’ effort to maintain a resting state. Functional connectivity data echoed these results, though they also showed links not reflected in the patterns of

  5. The effect of regulatory mode on procrastination: Bi-stable parahippocampus connectivity with dorsal anterior cingulate and anterior prefrontal cortex.

    Science.gov (United States)

    Zhang, Chenyan; Ni, Yan; Feng, Tingyong

    2017-06-30

    Previous research has elucidated that procrastination can be influenced by regulatory mode orientations. However, the neural mechanism of regulatory modes affecting procrastination is not well understood. To address this question, we employed resting-state functional magnetic resonance imaging (RS-fMRI) to test the influence of two regulatory modes (assessment and locomotion) on procrastination. The behavioral results showed that procrastination was positively correlated with assessment orientation but negatively correlated with locomotion orientation. Neuroimaging results indicated that the functional connectivity between parahippocampal cortex (PHC) and dorsal anterior cingulate (dACC) was negatively correlated with assessment scores, while the functional connectivity between anterior prefrontal cortex (aPFC) and parahippocampal cortex (PHC) was negatively correlated with locomotion scores. Critically, mediation analysis showed that the different effects of two distinct regulatory modes on procrastination were mediated by PHC-dACC and aPFC-PHC functional connectivity respectively. These results suggested that people's procrastination could be predicted by regulatory mode orientations, which is mediated by PHC connectivity with dACC and aPFC respectively. The present study extends our knowledge on procrastination and provides neural mechanism for understanding the link between regulatory mode orientations and procrastination. Copyright © 2017. Published by Elsevier B.V.

  6. Evaluation of connectivity map-discovered celastrol as a radiosensitizing agent in a murine lung carcinoma model: Feasibility study of diffusion-weighted magnetic resonance imaging.

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    Hong Young Jun

    Full Text Available This study was designed to identify potential radiosensitizing (RS agents for combined radio- and chemotherapy in a murine model of human lung carcinoma, and to evaluate the in vivo effect of the RS agents using diffusion-weighted magnetic resonance imaging (DW-MRI. Radioresistance-associated genes in A549 and H460 cells were isolated on the basis of their gene expression profiles. Celastrol was selected as a candidate RS by using connectivity mapping, and its efficacy in lung cancer radiotherapy was tested. Mice inoculated with A549 carcinoma cells were treated with single ionizing radiation (SIR, single celastrol (SC, or celastrol-combined ionizing radiation (CCIR. Changes in radiosensitization over time were assessed using DW-MRI before and at 3, 6, and 12 days after therapy initiation. The tumors were stained with hematoxylin and eosin at 6 and 12 days after therapy. The percentage change in the apparent diffusion coefficient (ADC value in the CCIR group was significantly higher than that in the SC and SIR group on the 12th day (Mann-Whitney U-test, p = 0.05; Kruskal-Wallis test, p < 0.05. A significant correlation (Spearman's rho correlation coefficient of 0.713, p = 0.001 was observed between the mean percentage tumor necrotic area and the mean ADC values after therapy initiation. These results suggest that the novel radiosensitizing agent celastrol has therapeutic effects when combined with ionizing radiation (IR, thereby maximizing the therapeutic effect of radiation in non-small cell lung carcinoma. In addition, DW-MRI is a useful noninvasive tool to monitor the effects of RS agents by assessing cellularity changes and sequential therapeutic responses.

  7. Effect of hot dip galvanization on the fatigue strength of steel bolted connections

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    S.M.J. Razavi

    2017-07-01

    Full Text Available Hot dip galvanized steel bolted joints has been tested under fatigue loading to evaluate the effect of galvanizing coating on the fatigue strength of S355 structural steel. The experimental results showed that the decrease of the fatigue life of coated specimens in comparison with that of uncoated joints is very limited and the results are in good agreement with Eurocode detail category, without substantial reductions. The procedure for coating and preparation of the bolted joints is described in detail in this paper providing a useful tool for engineers involved in similar practical applications. The experimental results are compared with the previously published data on central hole notched galvanized and not treated specimens characterized by the same geometry.

  8. A Simple Response Evaluation Method for Base-Isolation Building-Connection Hybrid Structural System under Long-Period and Long-Duration Ground Motion

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    Kohei Hayashi

    2018-02-01

    Full Text Available An innovative hybrid control building system of base-isolation and building-connection has been proposed in the previous study. This system has two advantages, (i to resist an impulsive earthquake input through the base-isolation system and (ii to withstand a long-duration earthquake input through the building-connection system. A simple response evaluation method without the need of non-linear time–history response analysis is proposed here for this hybrid building system under a long-period and long-duration ground motion. An analytical expression is derived in the plastic deformation of an elastic–perfectly plastic single-degree-of-freedom (SDOF model with viscous damping under the multi-impulse, which is the representative of long-period and long-duration ground motions. A transformation procedure of a base-isolation building-connection hybrid structural system into an SDOF model is proposed by introducing two steps, one is the reduction of the main base-isolated building to an SDOF system, and the other is the reduction of the connecting oil dampers supported on a free-wall to an oil damper with a newly introduced compensation factor on a rigid wall. Application of the analytical expression of the plastic deformation to the reduced SDOF model including the compensation factor on the connecting oil dampers enables the development of a simplified, but rather accurate response evaluation method. The time–history response analysis of the multi-degree-of-freedom model and the comparison with the proposed simplified formula make clear the accuracy and reliability of the proposed simplified response evaluation method.

  9. Passive advection-dispersion in networks of pipes: Effect of connectivity and relationship to permeability

    Science.gov (United States)

    Bernabé, Y.; Wang, Y.; Qi, T.; Li, M.

    2016-02-01

    The main purpose of this work is to investigate the relationship between passive advection-dispersion and permeability in porous materials presumed to be statistically homogeneous at scales larger than the pore scale but smaller than the reservoir scale. We simulated fluid flow through pipe network realizations with different pipe radius distributions and different levels of connectivity. The flow simulations used periodic boundary conditions, allowing monitoring of the advective motion of solute particles in a large periodic array of identical network realizations. In order to simulate dispersion, we assumed that the solute particles obeyed Taylor dispersion in individual pipes. When a particle entered a pipe, a residence time consistent with local Taylor dispersion was randomly assigned to it. When exiting the pipe, the particle randomly proceeded into one of the pipes connected to the original one according to probabilities proportional to the outgoing volumetric flow in each pipe. For each simulation we tracked the motion of at least 6000 solute particles. The mean fluid velocity was 10-3 ms-1, and the distance traveled was on the order of 10 m. Macroscopic dispersion was quantified using the method of moments. Despite differences arising from using different types of lattices (simple cubic, body-centered cubic, and face-centered cubic), a number of general observations were made. Longitudinal dispersion was at least 1 order of magnitude greater than transverse dispersion, and both strongly increased with decreasing pore connectivity and/or pore size variability. In conditions of variable hydraulic radius and fixed pore connectivity and pore size variability, the simulated dispersivities increased as power laws of the hydraulic radius and, consequently, of permeability, in agreement with previously published experimental results. Based on these observations, we were able to resolve some of the complexity of the relationship between dispersivity and permeability.

  10. Market Efficiency and Real Efficiency: The Connect and Disconnect via Feedback Effects

    OpenAIRE

    Liyan Yang; Itay Goldstein

    2014-01-01

    We study a model to explore the (dis)connect between market efficiency and real efficiency when real decision makers learn information from the market to guide their actions. We emphasize two channels that determine whether the two efficiency concepts are aligned. The "externality channel" says that individual learning outcomes may not always map into real efficiency because the presence of externality causes real decision makers to overuse the price information. The "(mis)match channel" emph...

  11. Effects of connection of electrical and mechanical potentials in inverse osmosis processes

    International Nuclear Information System (INIS)

    Cortes, Farid; Chejne, Farid; Chejne, David; Velez, Fredy; Londono, Carlos

    2009-01-01

    A theoretical dissertation and experimental assays of the irreversible phenomena applied to electro-kinetics and inverse osmosis is presented. Experimental assays were made on simple equipment to evidence the occurrence of connected irreversible phenomena between electric current flow and global mass flow. The coupling of these two phenomena allowed us to make conclusions about the possibility of reducing operation costs of the inverse osmosis equipment due to increasing the saline solution flow between 12% and 20%.

  12. Effects of connection of electrical and mechanical potentials in inverse osmosis processes

    Energy Technology Data Exchange (ETDEWEB)

    Cortes, Farid; Chejne, Farid; Chejne, David; Velez, Fredy; Londono, Carlos [Grupo de Termodinamica Aplicada y Energias Alternativas - TAYEA, Instituto de Energia, Facultad de Minas, Universidad Nacional de Colombia, Sede Medellin, Antigua (Colombia)

    2009-07-15

    A theoretical dissertation and experimental assays of the irreversible phenomena applied to electro-kinetics and inverse osmosis is presented. Experimental assays were made on simple equipment to evidence the occurrence of connected irreversible phenomena between electric current flow and global mass flow. The coupling of these two phenomena allowed us to make conclusions about the possibility of reducing operation costs of the inverse osmosis equipment due to increasing the saline solution flow between 12% and 20%. (author)

  13. Performance of IBS Precast Concrete Beam-Column Connections Under Earthquake Effects: A Literature Review

    OpenAIRE

    Patrick T.L. Yee; Azlan B. Adnan; Abdul K. Mirasa; Ahmad B.A. Rahman

    2011-01-01

    Problem statement: Despite demonstrating rather much benefits comparing to the conventional cast-in-place construction, the acceptance level of precast concrete building is still reportedly low in Malaysia. The implication imposed by stricter seismic design provisions would only worsen the matter. Approach: The main objective of this study was to identify the most appropriate type of beam-column connections to be introduced to precast concrete industry, particularly for re...

  14. Sediment transfer and connectivity analysis in an olive orchard microcatchment in Spain: a study case to evaluate the impact of rainfall variability and management

    Science.gov (United States)

    Taguas, Encarnación; Rebolledo, Juan; Vanwalleghem, Tom; Guzmán, Gema; Burguet, María; Gómez, Jose A.

    2016-04-01

    Quantification and description of sediment delivery processes at the catchment scale are essential to evaluate the main sources of sediments that contribute to soil degradation, and to design effective management strategies. Erosion derived from concentrated flow might imply a serious degradation risk which is not always apparent as is the case of rills and ephemeral gullies. The objectives of this work were: 1) to characterize the rills and ephemeral gullies measured for periods with different hydrological features in terms of precipitation and erosivity and management; and 2) to evaluate the contribution of concentrated flow to the sediment discharge measured at the catchment outlet. In this study, rills and ephemeral gullies generated during inter-tillage periods were measured 4 times in a period between April 2009 and March 2014. The measures were carried out in a 6.7 ha olive orchard of with conventional tillage until September 2014, when cover crops were seeded in some lanes following the most approximate direction to contours. Although rainfall, runoff and sediment discharge were monitored at the outlet for the complete study period, there were some very erosive events in which sediment concentration could not be measured. Hence, the SEDD model, previously calibrated (Burguet, 2015), was used to fill these gaps as well as to calculate the sediment delivery ratios in the catchment. The mean volume of rills and ephemeral gullies for the 4 surveys was equivalent to 8.1 t.ha-1 and 3.3 t.ha-1, respectively whereas the mean total sediment discharge for the same period was of 7.8 t.ha-1. The accumulated erosivity explained the differences of soil losses associated to rills better than accumulated precipitation. The impact of cover crops during 2014 was particularly notable on the reduction of the sediment loads in the events, as well as on the rill discontinuities and sediment trapping as observed in the field. An active sediment dynamics is expected in the

  15. Effects of internal and external vividness on hippocampal connectivity during memory retrieval.

    Science.gov (United States)

    Ford, Jaclyn H; Kensinger, Elizabeth A

    2016-10-01

    Successful memory for an image can be supported by retrieval of one's personal reaction to the image (i.e., internal vividness), as well as retrieval of the specific details of the image itself (i.e., external vividness). Prior research suggests that memory vividness relies on regions within the medial temporal lobe, particularly the hippocampus, but it is unclear whether internal and external vividness are supported by the hippocampus in a similar way. To address this open question, the current study examined hippocampal connectivity associated with enhanced internal and external vividness ratings during retrieval. Participants encoded complex visual images paired with verbal titles. During a scanned retrieval session, they were presented with the titles and asked whether each had been seen with an image during encoding. Following retrieval of each image, participants were asked to rate internal and external vividness. Increased hippocampal activity was associated with higher vividness ratings for both scales, supporting prior evidence implicating the hippocampus in retrieval of memory detail. However, different patterns of hippocampal connectivity related to enhanced external and internal vividness. Further, hippocampal connectivity with medial prefrontal regions was associated with increased ratings of internal vividness, but with decreased ratings of external vividness. These findings suggest that the hippocampus may contribute to increased internal and external vividness via distinct mechanisms and that external and internal vividness of memories should be considered as separable measures. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Perceptual decision-making difficulty modulates feedforward effective connectivity to the dorsolateral prefrontal cortex

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    Bidhan eLamichhane

    2015-09-01

    Full Text Available Diverse cortical structures are known to coordinate activity as a network in relaying and processing of visual information to discriminate visual objects. However, how this discrimination is achieved is still largely unknown. To contribute to answering this question, we used face-house categorization tasks with three levels of noise in face and house images in functional magnetic resonance imaging (fMRI experiments involving thirty-three participants. The behavioral performance error and response time (RT were correlated with noise in face-house images. We then built dynamical causal models (DCM of fMRI blood-oxygenation level dependent (BOLD signals from the face and house category-specific regions in ventral temporal cortex, the fusiform face area (FFA and parahippocampal place area (PPA, and the dorsolateral prefrontal cortex (dlPFC. We found a strong feed-forward intrinsic connectivity pattern from FFA and PPA to dlPFC. Importantly, the feed-forward connectivity to dlPFC was significantly modulated by the perception of both faces and houses. The dlPFC-BOLD activity, the connectivity from FFA and PPA to the dlPFC all increased with noise level. These results suggest that the FFA-PPA-dlPFC network plays an important role for relaying and integrating competing sensory information to arrive at perceptual decisions.

  17. Functional connectivity in task-negative network of the Deaf: effects of sign language experience

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    Evie Malaia

    2014-06-01

    Full Text Available Prior studies investigating cortical processing in Deaf signers suggest that life-long experience with sign language and/or auditory deprivation may alter the brain’s anatomical structure and the function of brain regions typically recruited for auditory processing (Emmorey et al., 2010; Pénicaud et al., 2013 inter alia. We report the first investigation of the task-negative network in Deaf signers and its functional connectivity—the temporal correlations among spatially remote neurophysiological events. We show that Deaf signers manifest increased functional connectivity between posterior cingulate/precuneus and left medial temporal gyrus (MTG, but also inferior parietal lobe and medial temporal gyrus in the right hemisphere- areas that have been found to show functional recruitment specifically during sign language processing. These findings suggest that the organization of the brain at the level of inter-network connectivity is likely affected by experience with processing visual language, although sensory deprivation could be another source of the difference. We hypothesize that connectivity alterations in the task negative network reflect predictive/automatized processing of the visual signal.

  18. Effects of Adhesive Connection on Composite Action between FRP Bridge Deck and Steel Girder

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2017-01-01

    Full Text Available The FRP-steel girder composite bridge system is increasingly used in new constructions of bridges as well as rehabilitation of old bridges. However, the understanding of composite action between FRP decks and steel girders is limited and needs to be systematically investigated. In this paper, depending on the experimental investigations of FRP to steel girder system, the Finite Element (FE models on experiments were developed and analyzed. Comparison between experiments and FE results indicated that the FE models were much stiffer for in-plane shear stiffness of the FRP deck panel. To modify the FE models, rotational spring elements were added between webs and flanges of FRP decks, to simulate the semirigid connections. Numerical analyses were also conducted on four-point bending experiments of FRP-steel composite girders. Good agreement between experimental results and FE analysis was achieved by comparing the load-deflection curves at midspan and contribution of composite action from FRP decks. With the validated FE models, the parametric studies were conducted on adhesively bonded connection between FRP decks and steel girders, which indicated that the loading transfer capacity of adhesive connection was not simply dependent on the shear modulus or thickness of adhesive layer but dominated by the in-plane shear stiffness K.

  19. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, J. R.; Dawley, Earl M.; Coleman, Andre M.; Ostrand, Kenneth G.; Hanson, Kyle C.; Woodruff, Dana L.; Donley, Erin E.; Ke, Yinghai; Buenau, Kate E.; Bryson, Amanda J.; Townsend, Richard L.

    2011-10-01

    This report describes the 2010 research conducted under the U.S. Army Corps of Engineers (USACE) project EST-P-09-1, titled Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, and known as the 'Salmon Benefits' study. The primary goal of the study is to establish scientific methods to quantify habitat restoration benefits to listed salmon and trout in the lower Columbia River and estuary (LCRE) in three required areas: habitat connectivity, early life history diversity, and survival (Figure ES.1). The general study approach was to first evaluate the state of the science regarding the ability to quantify benefits to listed salmon and trout from habitat restoration actions in the LCRE in the 2009 project year, and then, if feasible, in subsequent project years to develop quantitative indices of habitat connectivity, early life history diversity, and survival. Based on the 2009 literature review, the following definitions are used in this study. Habitat connectivity is defined as a landscape descriptor concerning the ability of organisms to move among habitat patches, including the spatial arrangement of habitats (structural connectivity) and how the perception and behavior of salmon affect the potential for movement among habitats (functional connectivity). Life history is defined as the combination of traits exhibited by an organism throughout its life cycle, and for the purposes of this investigation, a life history strategy refers to the body size and temporal patterns of estuarine usage exhibited by migrating juvenile salmon. Survival is defined as the probability of fish remaining alive over a defined amount of space and/or time. The objectives of the 4-year study are as follows: (1) develop and test a quantitative index of juvenile salmon habitat connectivity in the LCRE incorporating structural, functional, and hydrologic components; (2

  20. EEG-MEG Integration Enhances the Characterization of Functional and Effective Connectivity in the Resting State Network

    Science.gov (United States)

    Mideksa, Kidist Gebremariam; Anwar, Abdul Rauf; Stephani, Ulrich; Deuschl, Günther; Freitag, Christine M.; Siniatchkin, Michael

    2015-01-01

    At the sensor level many aspects, such as spectral power, functional and effective connectivity as well as relative-power-ratio ratio (RPR) and spatial resolution have been comprehensively investigated through both electroencephalography (EEG) and magnetoencephalography (MEG). Despite this, differences between both modalities have not yet been systematically studied by direct comparison. It remains an open question as to whether the integration of EEG and MEG data would improve the information obtained from the above mentioned parameters. Here, EEG (64-channel system) and MEG (275 sensor system) were recorded simultaneously in conditions with eyes open (EO) and eyes closed (EC) in 29 healthy adults. Spectral power, functional and effective connectivity, RPR, and spatial resolution were analyzed at five different frequency bands (delta, theta, alpha, beta and gamma). Networks of functional and effective connectivity were described using a spatial filter approach called the dynamic imaging of coherent sources (DICS) followed by the renormalized partial directed coherence (RPDC). Absolute mean power at the sensor level was significantly higher in EEG than in MEG data in both EO and EC conditions. At the source level, there was a trend towards a better performance of the combined EEG+MEG analysis compared with separate EEG or MEG analyses for the source mean power, functional correlation, effective connectivity for both EO and EC. The network of coherent sources and the spatial resolution were similar for both the EEG and MEG data if they were analyzed separately. Results indicate that the combined approach has several advantages over the separate analyses of both EEG and MEG. Moreover, by a direct comparison of EEG and MEG, EEG was characterized by significantly higher values in all measured parameters in both sensor and source level. All the above conclusions are specific to the resting state task and the specific analysis used in this study to have general

  1. THE EFFECTIVENESS OF USING CLUSTER CONNECTION TOWARDS STUDENTS’ VOCABULARY MASTERY AT THE EIGHTH GRADE OF MTs DARUL IHSAN DURI

    Directory of Open Access Journals (Sweden)

    Setiawati

    2017-12-01

    Full Text Available This study aimed to know The Effectiveness of Using Cluster Connection Towards The Students’ VocabularyMastery at The Eighth Graders at MTs Darul Ihsan Duri. Related to the object of the research, the researcher used experimental method. The design of the research was control and experiment group; pretest – posttest design. The research was conducted at MTs. Daru lIhsan Duri in the academic year 2015/2016. The population of this research was the eighth grade students of MTs Darul Ihsan Duri. The total population was 62 students. The sample of the research was class VIII.A as control class and class VIII.B as experimental class. Class VIII.A consisted of 31 students. Class VIII.B consisted of 31 students. In analyzing the research data, the researcher used Independent sampleT-Test. T-Test was used to know whether cluster connection technique is effective toward the students’ vocabulary mastery. The result of the research showed that using cluster connection technique was effective toward the students’ vocabulary mastery. Based on statistical calculation in data analysis, the researcher gave interpretation of posttest score in experiment class and the control class. From the calculation, t-test value was 2.627 and t-table was 2.00. Because t-test value (2.627 was higher than t-table (2.00, it could be concluded that alternative hypothesis (Ha was accepted and the null hypothesis (Ho was rejected. It means that teaching vocabulary by using cluster connection is effective

  2. Mapping effective connectivity in the human brain with concurrent intracranial electrical stimulation and BOLD-fMRI.

    Science.gov (United States)

    Oya, Hiroyuki; Howard, Matthew A; Magnotta, Vincent A; Kruger, Anton; Griffiths, Timothy D; Lemieux, Louis; Carmichael, David W; Petkov, Christopher I; Kawasaki, Hiroto; Kovach, Christopher K; Sutterer, Matthew J; Adolphs, Ralph

    2017-02-01

    Understanding brain function requires knowledge of how one brain region causally influences another. This information is difficult to obtain directly in the human brain, and is instead typically inferred from resting-state fMRI. Here, we demonstrate the safety and scientific promise of a novel and complementary approach: concurrent electrical stimulation and fMRI (es-fMRI) at 3T in awake neurosurgical patients with implanted depth electrodes. We document the results of safety testing, actual experimental setup, and stimulation parameters, that safely and reliably evoke activation in distal structures through stimulation of amygdala, cingulate, or prefrontal cortex. We compare connectivity inferred from the evoked patterns of activation with that estimated from standard resting-state fMRI in the same patients: while connectivity patterns obtained with each approach are correlated, each method produces unique results. Response patterns were stable over the course of 11min of es-fMRI runs. COMPARISON WITH EXISTING METHOD: es-fMRI in awake humans yields unique information about effective connectivity, complementing resting-state fMRI. Although our stimulations were below the level of inducing any apparent behavioral or perceptual effects, a next step would be to use es-fMRI to modulate task performances. This would reveal the acute network-level changes induced by the stimulation that mediate the behavioral and cognitive effects seen with brain stimulation. es-fMRI provides a novel and safe approach for mapping effective connectivity in the human brain in a clinical setting, and will inform treatments for psychiatric and neurodegenerative disorders that use deep brain stimulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  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 small-world connectivity on noise-induced temporal and spatial order in neural media

    International Nuclear Information System (INIS)

    Perc, Matjaz

    2007-01-01

    We present an overview of possible effects of small-world connectivity on noise-induced temporal and spatial order in a two-dimensional network of excitable neural media with FitzHugh-Nagumo local dynamics. Small-world networks are characterized by a given fraction of so-called long-range couplings or shortcut links that connect distant units of the system, while all other units are coupled in a diffusive-like manner. Interestingly, already a small fraction of these long-range couplings can have wide-ranging effects on the temporal as well as spatial noise-induced dynamics of the system. Here we present two main effects. First, we show that the temporal order, characterized by the autocorrelation of a firing-rate function, can be greatly enhanced by the introduction of small-world connectivity, whereby the effect increases with the increasing fraction of introduced shortcut links. Second, we show that the introduction of long-range couplings induces disorder of otherwise ordered, spiral-wave-like, noise-induced patterns that can be observed by exclusive diffusive connectivity of spatial units. Thereby, already a small fraction of shortcut links is sufficient to destroy coherent pattern formation in the media. Although the two results seem contradictive, we provide an explanation considering the inherent scale-free nature of small-world networks, which on one hand, facilitates signal transduction and thus temporal order in the system, whilst on the other hand, disrupts the internal spatial scale of the media thereby hindering the existence of coherent wave-like patterns. Additionally, the importance of spatially versus temporally ordered neural network functioning is discussed

  5. [Connection between the evaluation of positive or negative valence and verbal responses to a lexical decision making task].

    Science.gov (United States)

    Brouillet, Thibaut; Syssau, Arielle

    2005-12-01

    Evaluation of the positive or negative valence of a stimulus is an activity that is part of any emotional experience that has been mostly studied using the affective priming paradigm. When the prime and the target have the same valence (e.g. positive prime and positive target), the target response is facilitated as a function of opposing valence conditions (e.g. negative prime and positive target). These studies show that this evaluation is automatic but depends on the nature of the task's implied response because the priming effects are only observed for positive responses, not for negative responses. This result was explained in automatic judgmental tendency model put forth by Abelson and Rosenberg (1958) and Klauer and Stern (1992). In this model, affective priming assumes there is an overlap between both responses, the first response taking precedence as a function of the prime-target valence, and the second response one that is required by the task. We are assuming that another type of response was not foreseen under this model. In fact, upon activating the valence for each of the prime-target elements, two preliminary responses would be activated before the response on the prime-target valence relationship. These responses are directly linked to the prime and target evaluation independently of the prime-target relationship. This hypothesis can be linked to the larger hypothesis whereby the evaluative process is related to two distinct motivational systems corresponding to approach and avoidance behaviour responses (Lang, Bradley, & Cuthbert, 1990; Neuman & Strack, 2000; Cacciopo, Piester & Bernston, 1993). In this study, we use the hypothesis that when a word leads to a positive valence evaluation, this favours a positive verbal response and inversely, a negative valence word favours a negative response. We are testing this hypothesis outside the affective priming paradigm to study to what extent evaluating a word, even when it is not primed, activates both

  6. Evaluation of the Lateral Performance of Roof Truss-to-Wall Connections in Light-Frame Wood Systems

    Science.gov (United States)

    Andrew DeRenzis; Vladimir Kochkin; Xiping Wang

    2012-01-01

    This testing program was designed to benchmark the performance of traditional roof systems and incrementally improved roof-to-wall systems with the goal of developing connection solutions that are optimized for performance and constructability. Nine full-size roof systems were constructed and tested with various levels and types of heel detailing to measure the lateral...

  7. Is the internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? A systematic review.

    Science.gov (United States)

    Goiato, Marcelo Coelho; Pellizzer, Eduardo Piza; da Silva, Emily Vivianne Freitas; Bonatto, Liliane da Rocha; dos Santos, Daniela Micheline

    2015-09-01

    This systematic review aimed to evaluate if the internal connection is more efficient than the external connection and its associated influencing factors. A specific question was formulated according to the Population, Intervention, Control, and Outcome (PICO): Is internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? An electronic search of the MEDLINE and the Web of Knowledge databases was performed for relevant studies published in English up to November 2013 by two independent reviewers. The keywords used in the search included a combination of "dental implant" and "internal connection" or "Morse connection" or "external connection." Selected studies were randomized clinical trials, prospective or retrospective studies, and in vitro studies with a clear aim of investigating the internal and/or external implant connection use. From an initial screening yield of 674 articles, 64 potentially relevant articles were selected after an evaluation of their titles and abstracts. Full texts of these articles were obtained with 29 articles fulfilling the inclusion criteria. Morse taper connection has the best sealing ability. Concerning crestal bone loss, internal connections presented better results than external connections. The limitation of the present study was the absence of randomized clinical trials that investigated if the internal connection was more efficient than the external connection. The external and internal connections have different mechanical, biological, and esthetical characteristics. Besides all systems that show proper success rates and effectiveness, crestal bone level maintenance is more important around internal connections than external connections. The Morse taper connection seems to be more efficient concerning biological aspects, allowing lower bacterial leakage and bone loss in single implants, including aesthetic regions. Additionally, this connection type can be successfully

  8. Impaired functional connectivity of brain reward circuitry in patients with schizophrenia and cannabis use disorder: Effects of cannabis and THC.

    Science.gov (United States)

    Fischer, Adina S; Whitfield-Gabrieli, Susan; Roth, Robert M; Brunette, Mary F; Green, Alan I

    2014-09-01

    Cannabis use disorder (CUD) occurs in up to 42% of patients with schizophrenia and substantially worsens disease progression. The basis of CUD in schizophrenia is unclear and available treatments are rarely successful at limiting cannabis use. We have proposed that a dysregulated brain reward circuit (BRC) may underpin cannabis use in these patients. In the present pilot study, we used whole-brain seed-to-voxel resting state functional connectivity (rs-fc) to examine the BRC of patients with schizophrenia and CUD, and to explore the effects of smoked cannabis and orally administered delta-9-tetrahydrocannabinol (THC) on the BRC. 12 patients with schizophrenia and CUD and 12 control subjects each completed two fMRI resting scans, with patients administered either a 3.6% THC cannabis cigarette (n=6) or a 15 mg THC capsule (n=6) prior to their second scan. Results revealed significantly reduced connectivity at baseline in patients relative to controls, with most pronounced hypoconnectivity found between the nucleus accumbens and prefrontal cortical BRC regions (i.e., anterior prefrontal cortex, orbitofrontal cortex, and anterior cingulate cortex). Both cannabis and THC administration increased connectivity between these regions, in direct correlation with increases in plasma THC levels. This study is the first to investigate interregional connectivity of the BRC and the effects of cannabis and THC on this circuit in patients with schizophrenia and CUD. The findings from this pilot study support the use of rs-fc as a means of measuring the integrity of the BRC and the effects of pharmacologic agents acting on this circuit in patients with schizophrenia and CUD. Copyright © 2014. Published by Elsevier B.V.

  9. Monitoring the effectiveness evaluation of investment projects

    Directory of Open Access Journals (Sweden)

    Skopin Alex O.

    2012-02-01

    Full Text Available The article raised the question of monitoring regulatory evaluation of the effectiveness of regional investment projects. This is justified by the fact that the current regulatory framework defined indicators for measuring the effectiveness of regional investment projects, but these figures are usually used only at the design stage of the project, an interim assessment of the effectiveness of a sufficiently simplified and based on the level of exploration investment.

  10. Effective Connectivity of Cortical Sensorimotor Networks During Finger Movement Tasks: A Simultaneous fNIRS, fMRI, EEG Study.

    Science.gov (United States)

    Anwar, A R; Muthalib, M; Perrey, S; Galka, A; Granert, O; Wolff, S; Heute, U; Deuschl, G; Raethjen, J; Muthuraman, Muthuraman

    2016-09-01

    Recently, interest has been growing to understand the underlying dynamic directional relationship between simultaneously activated regions of the brain during motor task performance. Such directionality analysis (or effective connectivity analysis), based on non-invasive electrophysiological (electroencephalography-EEG) and hemodynamic (functional near infrared spectroscopy-fNIRS; and functional magnetic resonance imaging-fMRI) neuroimaging modalities can provide an estimate of the motor task-related information flow from one brain region to another. Since EEG, fNIRS and fMRI modalities achieve different spatial and temporal resolutions of motor-task related activation in the brain, the aim of this study was to determine the effective connectivity of cortico-cortical sensorimotor networks during finger movement tasks measured by each neuroimaging modality. Nine healthy subjects performed right hand finger movement tasks of different complexity (simple finger tapping-FT, simple finger sequence-SFS, and complex finger sequence-CFS). We focused our observations on three cortical regions of interest (ROIs), namely the contralateral sensorimotor cortex (SMC), the contralateral premotor cortex (PMC) and the contralateral dorsolateral prefrontal cortex (DLPFC). We estimated the effective connectivity between these ROIs using conditional Granger causality (GC) analysis determined from the time series signals measured by fMRI (blood oxygenation level-dependent-BOLD), fNIRS (oxygenated-O2Hb and deoxygenated-HHb hemoglobin), and EEG (scalp and source level analysis) neuroimaging modalities. The effective connectivity analysis showed significant bi-directional information flow between the SMC, PMC, and DLPFC as determined by the EEG (scalp and source), fMRI (BOLD) and fNIRS (O2Hb and HHb) modalities for all three motor tasks. However the source level EEG GC values were significantly greater than the other modalities. In addition, only the source level EEG showed a

  11. Comparative effect of implant-abutment connections, abutment angulations, and screw lengths on preloaded abutment screw using three-dimensional finite element analysis: An in vitro study

    OpenAIRE

    Krishna Chaitanya Kanneganti; Dileep Nag Vinnakota; Srinivas Rao Pottem; Mahesh Pulagam

    2018-01-01

    Purpose: The purpose of this study is to compare the effect of implant-abutment connections, abutment angulations, and screw lengths on screw loosening (SL) of preloaded abutment using three dimensional (3D) finite element analysis. Materials and Methods: 3D models of implants (conical connection with hex/trilobed connections), abutments (straight/angulated), abutment screws (short/long), and crown and bone were designed using software Parametric Technology Corporation Creo and assembled t...

  12. Effects of bleomycin and x irradiation on the frequency of chromosomal aberrations in selected connective tissue diseases

    International Nuclear Information System (INIS)

    Burkhardt, W.C. Jr.

    1978-01-01

    Whole blood lymphocytes from 28 patients with selected connective tissue disorders (6 progressive systemic sclerosis (PSS), 6 anti-nuclear antibody positive rheumatoid arthritis, 6 anti-nuclear antibody negative rheumatoid arthritis, 6 systemic lupus erythematosus, and 4 mixed connective tissue disease) and 17 controls matched for sex, age, and race were studied to determine the frequency of spontaneous as well as bleomycin and/or x-irradiation induced chromosomal aberrations. The effects of bleomycin on cultured lymphocytes were tested, but differential susceptibilities to this clastogen were not demonstrated among the disease groups and controls investigated. However, the combined effect of bleomycin and x irradiation were found to be additive in control lymphocytes, nearly additive in PSS, RA+, and SLE cultures, but reduced considerably from the expected additive value in Ra- cultures. This study indicated that peripheral blood lymphocytes from patients with connective tissue disease, as a whole, possess greater frequencies of spontaneous chromosomal aberrations than matched controls and that x rays can produce greater frequencies of chromosomal aberrations in whole blood lymphocytes of PSS patients than in suitably matched control individuals

  13. An investigation on the effect of gusset plate connection rigidity on the seismic behavior of special concentrically braced frames

    Directory of Open Access Journals (Sweden)

    Ali Esnaashari

    2016-12-01

    Full Text Available Special concentrically braced frames (SCBFs are commonly used to resist lateral loads in buildings. The bracing system sustains large deformations due to inelastic behavior in bracing members (buckling and yielding in tension. Generally, in the conventional modeling strategy, the effect of gusset plates in providing beam-column connections rigidity and hence, improving the post-buckling performance of these frames is not taken into account. This paper deals with the effect of gusset plate rigidity on the seismic behavior of SCBFs using Roeder’s proposed model in the literature. In this paper, four 3, 6, 9 and 12-story SCBFs were designed and modeled using two distinct methods: conventional method with hinged connections and Roeder’s method with semi-rigid connections. Then, the models behavior was investigated with both pushover analysis and nonlinear time-history analysis using OpenSees software. The results showed that lateral load capacity of the frames modeled with the Roeder’s proposed model are about 10% larger than the conventional method’s capacity. Also, it was found that the semi-rigid model leads to a less drift ratios and more overstrength factors.

  14. Abnormal resting state effective connectivity within the default mode network in major depressive disorder: A spectral dynamic causal modeling study.

    Science.gov (United States)

    Li, Liang; Li, Baojuan; Bai, Yuanhan; Liu, Wenlei; Wang, Huaning; Leung, Hoi-Chung; Tian, Ping; Zhang, Linchuan; Guo, Fan; Cui, Long-Biao; Yin, Hong; Lu, Hongbing; Tan, Qingrong

    2017-07-01

    Understanding the neural basis underlying major depressive disorder (MDD) is essential for the diagnosis and treatment of this mental disorder. Aberrant activation and functional connectivity of the default mode network (DMN) have been consistently found in patients with MDD. It is not known whether effective connectivity within the DMN is altered in MDD. The primary object of this study is to investigate the effective connectivity within the DMN during resting state in MDD patients before and after eight weeks of antidepressant treatment. We defined four regions of the DMN (medial frontal cortex, posterior cingulate cortex, left parietal cortex, and right parietal cortex) for each participant using a group independent component analysis. The coupling parameters reflecting the causal interactions among the DMN regions were estimated using spectral dynamic causal modeling (DCM). Twenty-seven MDD patients and 27 healthy controls were included in the statistical analysis. Our results showed declined influences from the left parietal cortex to other DMN regions in the pre-treatment patients as compared with healthy controls. After eight weeks of treatment, the influence from the right parietal cortex to the posterior cingulate cortex significantly decreased. These findings suggest that the reduced excitatory causal influence of the left parietal cortex is the key alteration of the DMN in patients with MDD, and the disrupted causal influences that parietal cortex exerts on the posterior cingulate cortex is responsive to antidepressant treatment.

  15. THE EFFECTIVENESS OF USING CLUSTER CONNECTION TOWARDS STUDENTS’ VOCABULARY MASTERY AT THE EIGHTH GRADE OF MTs DARUL IHSAN DURI

    Directory of Open Access Journals (Sweden)

    setiawati setiawati

    2017-12-01

    Full Text Available Penelitian ini bertujuan mengetahui keefektifan penggunaan cluster connection terhadap penguasaan kosakata siswa pada siswa kelas 8 MTs Darul Ihsan Duri. Behubungan dengan objek penelitian, peneliti menggunakan metode eksperimen. Model penelitiannya adalah kelompok pretest--post test untuk kelas control dan eksperimen. Penelitian ini diadakan pada MTs Darul Ihsan Duri pada tahun akademik 2015/2016. Populasi penelitian ini adalah kelas 8 MTs Darul Ihsan Duri pada tahun akademik 2015/2016. Total populasi penelitian adalah 62 siswa. Sampel penelitian ini adalah kelas VIII.A sebagai kelas kontrol, dan VIII.B sebagai kelas eksperimen. Kelas VIII.A terdiri atas 31 siswa. Kelas VIII.B terdiri atas 31 siswa. Dalam menganalisis data peneliti menggunakan Independent Sample T-Test. T-Test digunakan untuk mengetahui apakah teknik cluster connection effektif terhadap penguasaaan kosakata siswa. Hasil penelitian menunjukan bahwa penggunaan teknik cluster connection efektif terhadap penguasaaan kosakata siswa. Berdasarkan perhitungan statistic dalam menganalisis data peneliti memberikan tafsiran skor postest pada kelas eksperimen dan kelas kontrol. Dari perhitungan, t-test adalah 2.627 dan t-table adalah 2.00. karena nilai t-test (2.627 lebih tinggi dari pada t-table (2.00. Berdasarkan hasil penelitian, dapat disimpulkan bahwa alternative hipotesis (Ha diterima dan hipotesis null (Ho ditolak. Ini berarti pengajaran kosakata dengan teknik cluster connection adalah efektif.   This study aimed to know The Effectiveness of Using Cluster Connection Towards The Students’ VocabularyMastery at The Eighth Graders at MTs Darul Ihsan Duri. Related to the object of the research, the researcher used experimental method. The design of the research was control and experiment group; pretest – posttest design. The research was conducted at MTs. Daru lIhsan Duri in the academic year 2015/2016. The population of this research was the eighth grade students of MTs Darul Ihsan

  16. Effect of administration of oral contraceptives in vivo on collagen synthesis in tendon and muscle connective tissue in young women

    DEFF Research Database (Denmark)

    Hansen, M; Miller, B F; Holm, L

    2009-01-01

    concentrations of estradiol and progesterone (control, n = 12). Subjects performed 1 h of one-legged kicking exercise. The next day collagen fractional synthesis rates (FSR) in tendon and muscle connective tissue were measured after a flooding dose of [(13)C]proline followed by biopsies from the patellar tendon......, body composition, and exercise-training status were included. The two groups were either habitual users of oral contraceptives exposed to a high concentration of synthetic estradiol and progestogens (OC, n = 11), or non-OC-users tested in the follicular phase of the menstrual cycle characterized by low...... bioavailability of IGF-I in OC. In conclusion, synthetic female sex hormones administered as OC had an inhibiting effect on collagen synthesis in tendon, bone, and muscle connective tissue, which may be related to a lower bioavailability of IGF-I....

  17. An Applied Ecological Framework for Evaluating Infrastructure to Promote Walking and Cycling: The iConnect Study

    Science.gov (United States)

    Bull, Fiona; Powell, Jane; Cooper, Ashley R.; Brand, Christian; Mutrie, Nanette; Preston, John; Rutter, Harry

    2011-01-01

    Improving infrastructure for walking and cycling is increasingly recommended as a means to promote physical activity, prevent obesity, and reduce traffic congestion and carbon emissions. However, limited evidence from intervention studies exists to support this approach. Drawing on classic epidemiological methods, psychological and ecological models of behavior change, and the principles of realistic evaluation, we have developed an applied ecological framework by which current theories about the behavioral effects of environmental change may be tested in heterogeneous and complex intervention settings. Our framework guides study design and analysis by specifying the most important data to be collected and relations to be tested to confirm or refute specific hypotheses and thereby refine the underlying theories. PMID:21233429

  18. Assessment of factors connected with radiotherapy influencing the cosmetic effect in breast conserving therapy

    International Nuclear Information System (INIS)

    Blaszczyk, P.; Roszkowski, K.; Blaszczyk, E.; Kowalewski, J.

    2009-01-01

    Aim: To compare cosmetic results of different radiotherapy schedules used in the treatment of breast cancer after breast radiotherapy and to identify factors affecting cosmetic outcomes. Material and methods: Ninety-four patients irradiated. Median follow-up of 29 months (range 18-154 mo.). Patients were treated with standard fractionation 45-50 Gy/20-25 fx/4-5 weeks. Boost up to 10 Gy. Late effects were evaluated using the LENT-SOMA scoring scale. The cosmetic results were assessed on a four-point scale and presence of concomitant chemotherapy. Results: LENT-SOMA grade 3 toxicity was observed only in 8 (8,5%) patients. The factor associated with hyperpigmentation is large breast size. The significant risk factors for teleangiectasia are high dose and use photon energy 1,33 MeV beam. Factors found to impact significantly cosmetics adversely fibrosis was large breast size. Breast fibrosis were more frequent observed in woman after whole dose 50 Gy. There were no differences in breast skin thick between analysed factors. Conclusions: After irradiating large breasts more often than one observes the fibrosis of the breast in the case of small and average breasts and discolour of the skin. Irradiating photons from the cobalt source in the comparison with photons about higher energy at women with large breasts, there is the reason more frequent occurrence of the skin angioma. For the final cosmetic effect of radiotherapy in saving treatment, they do not have the impact: tumor size, boost method, chemical treatment, patients age. (authors)

  19. Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i

    International Nuclear Information System (INIS)

    Tillman, Fred D; Oki, Delwyn S.; Johnson, Adam G.; Barber, Larry B.; Beisner, Kimberly R.

    2014-01-01

    Highlights: • The connection between inland and coastal aquifers near Kona, Hawai‘i is uncertain. • If connected, increased inland groundwater pumping may threaten coastal ecosystems. • Connection of inland and coastal aquifers was investigated using geochemical data. • Stable isotope results provide strong evidence of a connection between the systems. • Other geochemical data suggest a connection but are not conclusive. - Abstract: Kaloko-Honokōhau National Historical Park (KAHO) is a coastal sanctuary on the western side of the Island of Hawai‘i that was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities. KAHO contains a variety of culturally and ecologically significant water resources and water-related habitat for species that have been declared as threatened or endangered by the U.S. Fish and Wildlife Service, or are candidate threatened or endangered species. These habitats are dependent on coastal unconfined groundwater in a freshwater-lens system. The coastal unconfined-groundwater system is recharged by local infiltration of rainfall but also may receive recharge from an inland groundwater system containing groundwater impounded to high altitudes. The area inland of and near KAHO is being rapidly urbanized and increased groundwater withdrawals from the inland impounded-groundwater system may affect habitat and water quality in KAHO, depending on the extent of connection between the coastal unconfined groundwater and inland impounded-groundwater. An investigation of the geochemistry of surface-water and groundwater samples in and near KAHO was performed to evaluate the presence or absence of a connection between the inland impounded- and coastal unconfined-groundwater systems in the area. Analyses of major ions, selected trace elements, rare-earth elements, and strontium-isotope ratio results from ocean, fishpond, anchialine pool, and groundwater samples were consistent with a linear

  20. Function connectivity MRI to evaluate the changes of the motorial nerve net in patients with brain tumors adjacent to the central sulcus occurred with reorganization of motor function

    International Nuclear Information System (INIS)

    Han Tong; Liu Meili; Cui Shimin; Liu Li; Jin Song; Lei Jing; Liu Hui; Guo Jun; Hao Nina; Guo Ying; Xiang Huadong; Weng Xuchu

    2008-01-01

    Objective: We investigated the changes of the motorial network in patients suffered from brain tumors adjacent to the central sulcus occurred with reorganization of motor function using function connectivity MRI (fcMRI) technique in order to provide the new evidence for the compensational hypothesis of the reorganization caused by focal lesions. Methods: Using 1.5 T MRI unit, 14 patients with brain tumors in the vicinity of the central sulcus occurred with reorganization of motor function and 6 normal volunteers were examined with fcMRI technique while the subjects performed no task. By selecting seed voxels (region of interest) in the regions showing the most activation in Mi area on the activated map and cross correlating with every, voxel within the brain, the fcMRI maps based on unilateral primary motor (M1) area were calculated. The location, extent and volume of the region showing significant connectivity to the several seed voxel, such as left/right M1 area in the health group and affected/unaffected Mlarea in the patient group were evaluated on the fcMRI map. Results: In healthy group, the extent and volume of the region showing significant connectivity to the left Mlarea [(9514.17±186.92)mm 3 ] were almost similar to those to the right M1 area [(9364.67±382.75) mm 3 ]. There showed no significant difference in motor connectivity between the two groups (P>0.05). In the tumor group, the volume of regions showing significant connectivity to the M1 area located in the affected hemisphere [(11193.14 ± 811.29) mm 3 ] was obviously higher than that of regions based on the seed voxel in the unaffected side [(6549.86± 400.94) mm 3 ] (t=20.383, P<0.01). The volume was significantly different among the regions showing high connectivity to the M1 of the affected side in patient group, those showing significant connectivity to the left M1 and right M1 in health group (P<0.01), the former was the biggest (P<0.01). The extent of the regions showing connectivity to

  1. Development of a software application to evaluate the performance and energy losses of grid-connected photovoltaic systems

    International Nuclear Information System (INIS)

    Trillo-Montero, D.; Santiago, I.; Luna-Rodriguez, J.J.; Real-Calvo, R.

    2014-01-01

    Highlights: • Software application to perform an automated analysis of grid-connected PV systems. • It integrates data from all devices registering data on typical PV installations. • Flexible to analyze installations with different configurations and components. • An analysis of two grid-connected PV systems located in Andalusia, was performed. • Temperature losses in summer months varying between 15% and 25% of energy production. - Abstract: The aim of this paper was to design and develop a software application that enables users to perform an automated analysis of data from the monitoring of grid-connected photovoltaic (PV) systems. This application integrates data from all devices already in operation such as environmental sensors, inverters and meters, which record information on typical PV installations. This required the development of a Relational Database Management System (RDBMS), consisting of a series of linked databases, enabling all PV system information to be stored; and a software, called S·lar, which enables all information from the monitoring to be automatically migrated to the database as well as determining some standard magnitudes related to performances and losses of PV installation components at different time scales. A visualization tool, which is both graphical and numerical, makes access to all of the information be a simple task. Moreover, the application enables relationships between parameters and/or magnitudes to be easily established. Furthermore, it can perform a preliminary analysis of the influence of PV installations on the distribution grids where the produced electricity is injected. The operation of such a software application was implemented by performing the analysis of two grid-connected PV installations located in Andalusia, Spain, via data monitoring therein. The monitoring took place from January 2011 to May 2012

  2. Risk effectiveness evaluation of surveillance testing

    International Nuclear Information System (INIS)

    Kim, I.S.; Samanta, P.K.; Martorell, S.; Vesely, W.E.

    1991-01-01

    To address the concerns about nuclear power plant surveillance tests, i.e., their adverse safety impact due to negative effects and too burdensome requirements, it is necessary to evaluate the safety significance or risk effectiveness of such tests explicitly considering both negative and positive effects. This paper defines the negative effects of surveillance testing from a risk perspective, and then presents a methodology to quantify the negative risk impact, i.e., the risk penalty or risk increase caused by the test. The method focuses on two important kinds of negative effects, namely, test-caused transients and test-caused equipment degradations. The concepts and quantitative methods for the risk evaluation can be used in the decision-making process to establish the safety significance of the tests and to screen the plant-specific surveillance test requirements. 6 refs., 2 figs., 2 tabs

  3. Effect of residual stress on the integrity of a branch connection

    International Nuclear Information System (INIS)

    Law, M.; Kirstein, O.; Luzin, V.

    2012-01-01

    A new connection to an existing gas pipeline was made by hot-tapping, welding directly onto a pressurised pipeline. The welds were not post-weld heat treated, causing significant residual stresses. The critical weld had residual stresses determined by neutron diffraction using ANSTO's residual stress diffractometer, Kowari. The maximum measured residual stress (290 MPa) was 60% of the yield strength. The magnitudes of errors from a number of sources were estimated. An integrity assessment of the welded branch connection was performed with the measured residual stress values and with residual stress distributions from the BS 7910 and API 579 analysis codes. Analysis using estimates of residual stress from API 579 overestimated the critical crack size. Highlights: ► Residual stresses were measured by neutron diffraction in a thick section, non post-weld heat treated ferritic weld. ► There is little published data on these welds. ► The work compares the measured residual stresses with code-based residual stress distributions.

  4. Effects of neck and circumoesophageal connective lesions on posture and locomotion in the cockroach.

    Science.gov (United States)

    Ridgel, Angela L; Ritzmann, Roy E

    2005-06-01

    Few studies in arthropods have documented to what extent local control centers in the thorax can support locomotion in absence of inputs from head ganglia. Posture, walking, and leg motor activity was examined in cockroaches with lesions of neck or circumoesophageal connectives. Early in recovery, cockroaches with neck lesions had hyper-extended postures and did not walk. After recovery, posture was less hyper-extended and animals initiated slow leg movements for multiple cycles. Neck lesioned individuals showed an increase in walking after injection of either octopamine or pilocarpine. The phase of leg movement between segments was reduced in neck lesioned cockroaches from that seen in intact animals, while phases in the same segment remained constant. Neither octopamine nor pilocarpine initiated changes in coordination between segments in neck lesioned individuals. Animals with lesions of the circumoesophageal connectives had postures similar to intact individuals but walked in a tripod gait for extended periods of time. Changes in activity of slow tibial extensor and coxal depressor motor neurons and concomitant changes in leg joint angles were present after the lesions. This suggests that thoracic circuits are sufficient to produce leg movements but coordinated walking with normal motor patterns requires descending input from head ganglia.

  5. Behavior of hybrid high-strength fiber reinforced concrete slab-column connections under the effect of high tempera

    Directory of Open Access Journals (Sweden)

    Reham H. Ahmed

    2016-04-01

    Full Text Available Concrete can be modified to perform in a more ductile form by the addition of randomly distributed discrete fibers in the concrete matrix. The combined effect of the addition of two types of fibers (steel fiber and polypropylene fiber with different percentages to concrete matrix, which is called hybrid effect is currently under investigation worldwide. The current research work presents the conducted experimental program to observe the behavior of hybrid high strength reinforced concrete slab-column connections under the effect of high temperature. For this purpose, ten slab-column connections were casted and tested. The experimental program was designed to investigate the effect of different variables such as concrete mixture, column location and temperature fighting system. All specimens were exposed to a temperature of 500 °C for duration of two hours. To observe the effect of each variable, specimens were divided into four groups according to the studied parameters. The test results revealed that using hybrid high strength concrete HFHSC produced more strength in punching failure compared with high strength concrete HSC when exposed to elevated temperature. Fighting by air had higher initial crack load compared with that for without fighting and fighting by water. On the other hand, fighting by water decreased the ultimate load.

  6. Conducting evaluations to determine training effectiveness

    International Nuclear Information System (INIS)

    Hall, J. Doug; Yoder, John A. Yoder

    2003-01-01

    Training organizations must answer the question: Is the training program adding value in terms of workforce productivity and safety? To answer this question, one needs to know what circumstances led to the development of training to determine how to measure the result of Gaining. The Idaho National Engineering and Environmental Laboratory (ENEEL), under contract with the United States Department Of Energy (U.S. DOE), has conducted extensive research hi the area of training effectiveness. A comprehensive Training Performance Indicator Model has been developed, which has become the basis for a DRAFT document entitled Guidance for Conducting Evaluations to Determine Training Effectiveness'. The indicator Model includes the performance indicators, strategies, and methods for measuring training effectiveness. A common nomenclature is used throughout the DRAFT document to aid in using and understanding training effectiveness evaluations. The model incorporates elements of Dr. Donald L. Kirkpatrick's evaluation model, other models from industry leaders, and the findings of a benchmarking study involving both nuclear and non-nuclear industry professionals. This presentation communicates recent Department of Energy efforts in evaluating effectiveness of training, including valuable lessons learned. (author)

  7. Effects of ostracism and social connection-related activities on adolescents' motivation to eat and energy intake.

    Science.gov (United States)

    Salvy, Sarah-Jeanne; Bowker, Julie C; Nitecki, Lauren A; Kluczynski, Melissa A; Germeroth, Lisa J; Roemmich, James N

    2012-01-01

    Assess the effect of ostracism and social connection-related activities on adolescents' motivation to eat and their energy intake. Participants (n = 103; M age = 13.6 years) were either ostracized or included when playing a computer game, Cyberball. Next, they wrote about their friend (social-connection), watched television (distraction), or completed Sudoku puzzles (cognitive-load), and then completed a task to earn points toward snack food and/or socializing. Afterwards, participants were given access to food and social activities. Ostracized adolescents were more motivated to earn food than adolescents who were in the included/control condition. Follow-up contrasts indicated that ostracized adolescents who wrote about friends worked more for food points and consumed more food than other adolescents. Results suggest that social connection-related activities following ostracism may further deplete self-regulatory resources, thereby resulting in increased unhealthy food patterns. Study limitations as well as clinical implications of these findings are discussed.

  8. Attentional control underlies the perceptual load effect: Evidence from voxel-wise degree centrality and resting-state functional connectivity.

    Science.gov (United States)

    Yin, Shouhang; Liu, Lu; Tan, Jinfeng; Ding, Cody; Yao, Dezhong; Chen, Antao

    2017-10-24

    The fact that interference from peripheral distracting information can be reduced in high perceptual load tasks has been widely demonstrated in previous research. The modulation from the perceptual load is known as perceptual load effect (PLE). Previous functional magnetic resonance imaging (fMRI) studies on perceptual load have reported the brain areas implicated in attentional control. To date, the contribution of attentional control to PLE and the relationship between the organization of functional connectivity and PLE are still poorly understood. In the present study, we used resting-state fMRI to explore the association between the voxel-wise degree centrality (DC) and PLE in an individual differences design and further investigated the potential resting-state functional connectivity (RSFC) contributing to individual's PLE. DC-PLE correlation analysis revealed that PLE was positively associated with the right middle temporal visual area (MT)-one of dorsal attention network (DAN) nodes. Furthermore, the right MT functionally connected to the conventional DAN and the RSFCs between right MT and DAN nodes were also positively associated with individual difference in PLE. The results suggest an important role of attentional control in perceptual load tasks and provide novel insights into the understanding of the neural correlates underlying PLE. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Internet Connectivity

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Internet Connectivity. BSNL, SIFY, HCL in Guwahati; only BSNL elsewhere in NE (local player in Shillong). Service poor; All vendors lease BW from BSNL.

  10. Mathematics Connection

    African Journals Online (AJOL)

    MATHEMATICS CONNECTION aims at providing a forum topromote the development of Mathematics Education in Ghana. Articles that seekto enhance the teaching and/or learning of mathematics at all levels of theeducational system are welcome.

  11. 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...

  12. Altered effective connectivity contributes to micrographia in patients with Parkinson's disease and freezing of gait.

    Science.gov (United States)

    Nackaerts, Evelien; Nieuwboer, Alice; Broeder, Sanne; Swinnen, Stephan; Vandenberghe, Wim; Heremans, Elke

    2018-02-01

    Recently, it was shown that patients with Parkinson's disease (PD) and freezing of gait (FOG) can also experience freezing episodes during handwriting and present writing problems outside these episodes. So far, the neural networks underlying increased handwriting problems in subjects with FOG are unclear. This study used dynamic causal modeling of fMRI data to investigate neural network dynamics underlying freezing-related handwriting problems and how these networks changed in response to visual cues. Twenty-seven non-freezers and ten freezers performed a pre-writing task with and without visual cues in the scanner with their right hand. The results showed that freezers and non-freezers were able to recruit networks involved in cued and uncued writing in a similar fashion. Whole group analysis also revealed a trend towards altered visuomotor integration in patients with FOG. Next, we controlled for differences in disease severity between both patient groups using a sensitivity analysis. For this, a subgroup of ten non-freezers matched for disease severity was selected by an independent researcher. This analysis further exposed significantly weaker coupling in mostly left hemispheric visuo-parietal, parietal - supplementary motor area, parietal - premotor, and premotor-M1 pathways in freezers compared to non-freezers, irrespective of cues. Correlation analyses revealed that these impairments in connectivity were related to writing amplitude and quality. Taken together, these findings show that freezers have reduced involvement of the supplementary motor area in the motor network, which explains the impaired writing amplitude regulation in this group. In addition, weaker supportive premotor connectivity may have contributed to micrographia in freezers, a pattern that was independent of cueing.

  13. Modeling the Effects of Connecting Side Channels to the Long Tom River, Oregon

    Science.gov (United States)

    Appleby, C.; McDowell, P. F.

    2015-12-01

    The lower Long Tom River is a heavily managed, highly modified stream in the southwestern Willamette Valley with many opportunities for habitat improvements and river restoration. In the 1940s and 1950s, the US Army Corps of Engineers dramatically altered this river system by constructing the Fern Ridge Dam and three, large drop structures, converting the River from a highly sinuous channel to a straight, channelized stream that is interrupted by these grade control structures, and removed the majority of the riparian vegetation. As a result, juvenile spring Chinook salmon are no longer found in the Watershed and the local population of coastal cutthroat trout face limited aquatic habitat. When the river was channelized, long sections of the historical channel were left abandoned on the floodplain. Reconnecting these historical channels as side channels may improve the quality and quantity of aquatic habitat and could allow fish passage around current barriers. However, such construction may also lead to undesirable threats to infrastructure and farmland. This study uses multiple HEC-RAS models to determine the impact of reconnecting two historical channels to the lower Long Tom River by quantifying the change in area of flood inundation and identifying infrastructure in jeapordy given current and post-restoration conditions for 1.5, 5, 10, and 25-year flood discharges. Bathymetric data from ADCP and RTK-GPS surveys has been combined with LiDAR-derived topographic data to create continuous elevation models. Several types of side channel connections are modeled in order to determine which type of connection will result in both the greatest quantity of accessible habitat and the fewest threats to public and private property. In the future, this study will also consider the change in the quantity of physical salmonid habitat and map the areas prone to sedimentation and erosion using CEASAR and PHABSIM tools.

  14. Deterministic influences exceed dispersal effects on hydrologically-connected microbiomes: Deterministic assembly of hyporheic microbiomes

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Emily B. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Crump, Alex R. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Resch, Charles T. [Geochemistry Department, Pacific Northwest National Laboratory, Richland WA USA; Fansler, Sarah [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Arntzen, Evan [Environmental Compliance and Emergency Preparation, Pacific Northwest National Laboratory, Richland WA USA; Kennedy, David W. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Fredrickson, Jim K. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA; Stegen, James C. [Biological Sciences Division, Pacific Northwest National Laboratory, Richland WA USA

    2017-03-28

    Subsurface zones of groundwater and surface water mixing (hyporheic zones) are regions of enhanced rates of biogeochemical cycling, yet ecological processes governing hyporheic microbiome composition and function through space and time remain unknown. We sampled attached and planktonic microbiomes in the Columbia River hyporheic zone across seasonal hydrologic change, and employed statistical null models to infer mechanisms generating temporal changes in microbiomes within three hydrologically-connected, physicochemically-distinct geographic zones (inland, nearshore, river). We reveal that microbiomes remain dissimilar through time across all zones and habitat types (attached vs. planktonic) and that deterministic assembly processes regulate microbiome composition in all data subsets. The consistent presence of heterotrophic taxa and members of the Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) superphylum nonetheless suggests common selective pressures for physiologies represented in these groups. Further, co-occurrence networks were used to provide insight into taxa most affected by deterministic assembly processes. We identified network clusters to represent groups of organisms that correlated with seasonal and physicochemical change. Extended network analyses identified keystone taxa within each cluster that we propose are central in microbiome composition and function. Finally, the abundance of one network cluster of nearshore organisms exhibited a seasonal shift from heterotrophic to autotrophic metabolisms and correlated with microbial metabolism, possibly indicating an ecological role for these organisms as foundational species in driving biogeochemical reactions within the hyporheic zone. Taken together, our research demonstrates a predominant role for deterministic assembly across highly-connected environments and provides insight into niche dynamics associated with seasonal changes in hyporheic microbiome composition and metabolism.

  15. Impaired consciousness is linked to changes in effective connectivity of the posterior cingulate cortex within the default mode network.

    Science.gov (United States)

    Crone, Julia Sophia; Schurz, Matthias; Höller, Yvonne; Bergmann, Jürgen; Monti, Martin; Schmid, Elisabeth; Trinka, Eugen; Kronbichler, Martin

    2015-04-15

    The intrinsic connectivity of the default mode network has been associated with the level of consciousness in patients with severe brain injury. Especially medial parietal regions are considered to be highly involved in impaired consciousness. To better understand what aspect of this intrinsic architecture is linked to consciousness, we applied spectral dynamic causal modeling to assess effective connectivity within the default mode network in patients with disorders of consciousness. We included 12 controls, 12 patients in minimally conscious state and 13 in vegetative state in this study. For each subject, we first defined the four key regions of the default mode network employing a subject-specific independent component analysis approach. The resulting regions were then included as nodes in a spectral dynamic causal modeling analysis in order to assess how the causal interactions across these regions as well as the characteristics of neuronal fluctuations change with the level of consciousness. The resulting pattern of interaction in controls identified the posterior cingulate cortex as the main driven hub with positive afferent but negative efferent connections. In patients, this pattern appears to be disrupted. Moreover, the vegetative state patients exhibit significantly reduced self-inhibition and increased oscillations in the posterior cingulate cortex compared to minimally conscious state and controls. Finally, the degree of self-inhibition and strength of oscillation in this region is correlated with the level of consciousness. These findings indicate that the equilibrium between excitatory connectivity towards posterior cingulate cortex and its feedback projections is a key aspect of the relationship between alterations in consciousness after severe brain injury and the intrinsic functional architecture of the default mode network. This impairment might be principally due to the disruption of the mechanisms underlying self-inhibition and neuronal

  16. Evaluating the effectiveness of impact assessment instruments

    DEFF Research Database (Denmark)

    Cashmore, Matthew; Richardson, Tim; Hilding-Ryedvik, Tuija

    2010-01-01

    to sharpen effectiveness evaluation theory for impact assessment instruments this article critically examines the neglected issue of their political constitution. Analytical examples are used to concretely explore the nature and significance of the politicisation of impact assessment. It is argued......The central role of impact assessment instruments globally in policy integration initiatives has been cemented in recent years. Associated with this trend, but also reflecting political emphasis on greater accountability in certain policy sectors and a renewed focus on economic competitiveness...... that raising awareness about the political character of impact assessment instruments, in itself, is a vital step in advancing effectiveness evaluation theory. Broader theoretical lessons on the framing of evaluation research are also drawn from the political analysis. We conclude that, at least within...

  17. Creating psychological connections between intervention recipients: development and focus group evaluation of a group singing session for people with aphasia.

    Science.gov (United States)

    Tarrant, Mark; Warmoth, Krystal; Code, Chris; Dean, Sarah; Goodwin, Victoria A; Stein, Ken; Sugavanam, Thavapriya

    2016-02-23

    The study sought to identify key design features that could be used to create a new framework for group-based health interventions. We designed and tested the first session of a group intervention for stroke survivors with aphasia which was aimed at nurturing new psychological connections between group members. The intervention session, a participant focus group and interviews with intervention facilitators were held in a local community music centre in the South West of England. A convenience sample of 10 community-dwelling people with poststroke aphasia participated in the session. Severity of aphasia was not considered for inclusion. Participants took part in a 90-min group singing session which involved singing songs from a specially prepared song book. Musical accompaniment was provided by the facilitators. Participants and group facilitators reported their experiences of participating in the session, with a focus on activities within the session related to the intervention aims. Researcher observations of the session were also made. Two themes emerged from the analysis, concerning experiences of the session ('developing a sense of group belonging') and perceptions of its design and delivery ('creating the conditions for engagement'). Participants described an emerging sense of shared social identity as a member of the intervention group and identified fixed (eg, group size, session breaks) and flexible (eg, facilitator responsiveness) features of the session which contributed to this emergence. Facilitator interviews and researcher observations corroborated and expanded participant reports. Engagement with health intervention content may be enhanced in group settings when intervention participants begin to establish positive and meaningful psychological connections with other group members. Understanding and actively nurturing these connections should be a core feature of a general framework for the design and delivery of group interventions. Published by the

  18. Creating psychological connections between intervention recipients: development and focus group evaluation of a group singing session for people with aphasia

    Science.gov (United States)

    Tarrant, Mark; Warmoth, Krystal; Code, Chris; Dean, Sarah; Goodwin, Victoria A; Stein, Ken; Sugavanam, Thavapriya

    2016-01-01

    Objectives The study sought to identify key design features that could be used to create a new framework for group-based health interventions. We designed and tested the first session of a group intervention for stroke survivors with aphasia which was aimed at nurturing new psychological connections between group members. Setting The intervention session, a participant focus group and interviews with intervention facilitators were held in a local community music centre in the South West of England. Participants A convenience sample of 10 community-dwelling people with poststroke aphasia participated in the session. Severity of aphasia was not considered for inclusion. Intervention Participants took part in a 90-min group singing session which involved singing songs from a specially prepared song book. Musical accompaniment was provided by the facilitators. Primary and secondary outcome measures Participants and group facilitators reported their experiences of participating in the session, with a focus on activities within the session related to the intervention aims. Researcher observations of the session were also made. Results Two themes emerged from the analysis, concerning experiences of the session (‘developing a sense of group belonging’) and perceptions of its design and delivery (‘creating the conditions for engagement’). Participants described an emerging sense of shared social identity as a member of the intervention group and identified fixed (eg, group size, session breaks) and flexible (eg, facilitator responsiveness) features of the session which contributed to this emergence. Facilitator interviews and researcher observations corroborated and expanded participant reports. Conclusions Engagement with health intervention content may be enhanced in group settings when intervention participants begin to establish positive and meaningful psychological connections with other group members. Understanding and actively nurturing these connections

  19. An Evaluation of "Effective Communication Skills" Coursebook

    Science.gov (United States)

    Ahmed, Shameem

    2016-01-01

    In Communicative Language Teaching situation, role of material is not only important but also inevitable. In the traditional context of English teaching textbooks are considered the main source of materials. This paper will provide an evaluation of "Effective Communication Skills" ("ECS") coursebook that has been introduced as…

  20. Evaluation of context effects in sentence recognition

    NARCIS (Netherlands)

    Bronkhorst, A.W.; Brand, T.; Wagener, K.

    2002-01-01

    It was investigated whether the model for context effects, developed earlier by Bronkhorst et al. [J. Acoust. Soc. Am. 93, 499-509 (1993)], can be applied to results of sentence tests, used for the evaluation of speech recognition. Data for two German sentence tests, that differed with respect to

  1. Use of hydrochemistry and environmental isotopes for evaluation of the hydrological connection between groundwater and wetland swamp Colombia

    International Nuclear Information System (INIS)

    Santa A, Diana P; Martinez F, Diana C; Betancur V, Teresita

    2008-01-01

    The understanding of water flow paths around a wetland is based on the hydrologic information interpretation. Although the incorporation of non-conventional techniques like hydrochemistry and isotopic hydrology allows a major compression level of hydrologic systems: They allow identify origin and evolution of water, movement times, permanence in the hydrologic cycle components. Cienaga Colombia wetland and its catch area, represent a strategic ecosystem located in the Bajo Cauca antioqueno. The natural conditions and the consequences of the human intervention on the wetland impose the need to approach its study and understanding, seeking to be able lo design effective measures to guarantee its sustainability. We presents the firsts results of the project developed by Antioquia University and IAEA: Hydrochemical and Isotopic techniques for the assessment of hydrological processes in the wetlands of Bajo Cauca Antioqueno which is part of the program: Isotopic techniques for assessment of hydrological processes in wetlands by International Atomic Energy Agency, IAEA. The general objective of the study is evaluate the dynamic of water flow, in and out of the wetland in the Bajo Cauca Antioqueno, using geochemical and isotopic techniques.

  2. A Technical Evaluation of Wireless Connectivity from Patient Monitors to an Anesthesia Information Management System During Intensive Care Unit Surgery.

    Science.gov (United States)

    Simpao, Allan F; Galvez, Jorge A; England, W Randall; Wartman, Elicia C; Scott, James H; Hamid, Michael M; Rehman, Mohamed A; Epstein, Richard H

    2016-02-01

    Surgical procedures performed at the bedside in the neonatal intensive care unit (NICU) at The Children's Hospital of Philadelphia were documented using paper anesthesia records in contrast to the operating rooms, where an anesthesia information management system (AIMS) was used for all cases. This was largely because of logistical problems related to connecting cables between the bedside monitors and our portable AIMS workstations. We implemented an AIMS for documentation in the NICU using wireless adapters to transmit data from bedside monitoring equipment to a portable AIMS workstation. Testing of the wireless AIMS during simulation in the presence of an electrosurgical generator showed no evidence of interference with data transmission. Thirty NICU surgical procedures were documented via the wireless AIMS. Two wireless cases exhibited brief periods of data loss; one case had an extended data gap because of adapter power failure. In comparison, in a control group of 30 surgical cases in which wired connections were used, there were no data gaps. The wireless AIMS provided a simple, unobtrusive, portable alternative to paper records for documenting anesthesia records during NICU bedside procedures.

  3. Development and evaluation of a connective tissue phantom model for subsurface visualization of cancers requiring wide local excision

    Science.gov (United States)

    Samkoe, Kimberley S.; Bates, Brent D.; Tselepidakis, Niki N.; DSouza, Alisha V.; Gunn, Jason R.; Ramkumar, Dipak B.; Paulsen, Keith D.; Pogue, Brian W.; Henderson, Eric R.

    2017-12-01

    Wide local excision (WLE) of tumors with negative margins remains a challenge because surgeons cannot directly visualize the mass. Fluorescence-guided surgery (FGS) may improve surgical accuracy; however, conventional methods with direct surface tumor visualization are not immediately applicable, and properties of tissues surrounding the cancer must be considered. We developed a phantom model for sarcoma resection with the near-infrared fluorophore IRDye 800CW and used it to iteratively define the properties of connective tissues that typically surround sarcoma tumors. We then tested the ability of a blinded surgeon to resect fluorescent tumor-simulating inclusions with ˜1-cm margins using predetermined target fluorescence intensities and a Solaris open-air fluorescence imaging system. In connective tissue-simulating phantoms, fluorescence intensity decreased with increasing blood concentration and increased with increasing intralipid concentrations. Fluorescent inclusions could be resolved at ≥1-cm depth in all inclusion concentrations and sizes tested. When inclusion depth was held constant, fluorescence intensity decreased with decreasing volume. Using targeted fluorescence intensities, a blinded surgeon was able to successfully excise inclusions with ˜1-cm margins from fat- and muscle-simulating phantoms with inclusion-to-background contrast ratios as low as 2∶1. Indirect, subsurface FGS is a promising tool for surgical resection of cancers requiring WLE.

  4. Investigation of the sideband effect for the LCL-type grid-connected inverter with high LCL resonance frequency

    DEFF Research Database (Denmark)

    Yang, Dongsheng; Wang, Xiongfei; Blaabjerg, Frede

    2017-01-01

    The LCL-type grid connected inverter has been widely used as the intelligent power interface between the distributed generation unit and the power grid. To reduce the cost and volume of the filter, it is desirable to design the LCL filter with higher resonance frequency provided that the quality...... of injected grid current is not compromised. Actually, it is the typical case for the T-type or NPC three-level inverter to design its LCL resonance frequency close to half of the switching frequency. In this case, however, the sideband effect of SPWM modulation can impose a significant impact on the system...

  5. Multi-taxa population connectivity in the northern Rocky Mountains

    Science.gov (United States)

    Samuel A. Cushman; Erin L. Landguth

    2012-01-01

    Effective broad-spectrum biodiversity conservation requires that conservation strategies simultaneously meet the needs of multiple species. However, little is known about how maintaining habitat connectivity for one species or species group may also act as an umbrella for other species. We evaluated the degree to which predicted connected habitat for each of 144...

  6. "I feel more connected to the physically ideal mini me than the mirror-image mini me": theoretical implications of the "malleable self" for speculations on the effects of avatar creation on avatar-self connection in Wii.

    Science.gov (United States)

    Jin, Seung-A Annie

    2010-10-01

    What are the impacts of creating an avatar replicating the actual self versus an avatar projecting the ideal self on game players' avatar-self connection? This study leveraged an avatar-creating game (Mii Channel) within a video-game console (Wii) in a controlled, randomized study. The results of a two-group comparison (actual self-priming vs. ideal self-priming) between-subjects study (N = 76) demonstrated the significant main effect of self-priming via avatar (Mii) creation on avatar-self connection. Game players who were primed to create a Mii reflecting the ideal self felt greater avatar-self connection than those primed to create a replica Mii mirroring the actual self. Theoretical values and implications for a burgeoning body of research on the "malleable self" and the multidimensionality of the self-concept in avatar-based interactive media are discussed.

  7. A Component-Based Study of the Effect of Diameter on Bond and Anchorage Characteristics of Blind-Bolted Connections.

    Directory of Open Access Journals (Sweden)

    Muhammad Nasir Amin

    Full Text Available Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the "Extended Hollo-Bolt" (EHB due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach.

  8. A Component-Based Study of the Effect of Diameter on Bond and Anchorage Characteristics of Blind-Bolted Connections.

    Science.gov (United States)

    Amin, Muhammad Nasir; Zaheer, Salman; Alazba, Abdulrahman Ali; Saleem, Muhammad Umair; Niazi, Muhammad Umar Khan; Khurram, Nauman; Amin, Muhammad Tahir

    2016-01-01

    Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the "Extended Hollo-Bolt" (EHB) due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach.

  9. Effects of training strategies implemented in a complex videogame on functional connectivity of attentional networks.

    Science.gov (United States)

    Voss, Michelle W; Prakash, Ruchika Shaurya; Erickson, Kirk I; Boot, Walter R; Basak, Chandramallika; Neider, Mark B; Simons, Daniel J; Fabiani, Monica; Gratton, Gabriele; Kramer, Arthur F

    2012-01-02

    We used the Space Fortress videogame, originally developed by cognitive psychologists to study skill acquisition, as a platform to examine learning-induced plasticity of interacting brain networks. Novice videogame players learned Space Fortress using one of two training strategies: (a) focus on all aspects of the game during learning (fixed priority), or (b) focus on improving separate game components in the context of the whole game (variable priority). Participants were scanned during game play using functional magnetic resonance imaging (fMRI), both before and after 20 h of training. As expected, variable priority training enhanced learning, particularly for individuals who initially performed poorly. Functional connectivity analysis revealed changes in brain network interaction reflective of more flexible skill learning and retrieval with variable priority training, compared to procedural learning and skill implementation with fixed priority training. These results provide the first evidence for differences in the interaction of large-scale brain networks when learning with different training strategies. Our approach and findings also provide a foundation for exploring the brain plasticity involved in transfer of trained abilities to novel real-world tasks such as driving, sport, or neurorehabilitation. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Differential and distributed effects of dopamine neuromodulations on resting-state network connectivity

    NARCIS (Netherlands)

    Cole, D.M.; Beckmann, Christian; Oei, N.Y.L.; Both, S.; van Gerven, J.M.A.; Rombouts, S.A.R.B.

    2013-01-01

    Dopaminergic medications, used to treat neurochemical pathology and resultant symptoms in neuropsychiatric disorders, are of mixed efficacy and regularly associated with behavioural side effects. The possibility that dopamine exerts both linear and nonlinear ('inverted U-shaped') effects on

  11. Differential and distributed effects of dopamine neuromodulations on resting-state network connectivity

    NARCIS (Netherlands)

    Cole, D.M.; Beckmann, C.F.; Oei, N.Y.L.; Both, S.; van Gerven, J.M.A.; Rombouts, S.A.R.B.

    Dopaminergic medications, used to treat neurochemical pathology and resultant symptoms in neuropsychiatric disorders, are of mixed efficacy and regularly associated with behavioural side effects. The possibility that dopamine exerts both linear and nonlinear ('inverted U-shaped') effects on

  12. Establishing Connectivity

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    Global law settings are characterised by a structural pre-eminence of connectivity norms, a type of norm which differs from coherency or possibility norms. The centrality of connectivity norms emerges from the function of global law, which is to increase the probability of transfers of condensed ...... and human rights can be understood as serving a constitutionalising function aimed at stabilising and facilitating connectivity. This allows for an understanding of colonialism and contemporary global governance as functional, but not as normative, equivalents.......Global law settings are characterised by a structural pre-eminence of connectivity norms, a type of norm which differs from coherency or possibility norms. The centrality of connectivity norms emerges from the function of global law, which is to increase the probability of transfers of condensed...... social components, such as economic capital and products, religious doctrines and scientific knowledge, from one legally structured context to another within world society. This was the case from colonialism and colonial law to contemporary global supply chains and human rights. Both colonial law...

  13. Vegetation Cover Dynamics and Resilience to Climatic and Hydrological Disturbances in Seasonal Floodplain: The Effects of Hydrological Connectivity

    Directory of Open Access Journals (Sweden)

    Linlu Shi

    2017-12-01

    Full Text Available Floodplain wetlands are valuable ecosystems for maintaining biodiversity, but are vulnerable to hydrological modification and climatic extremes. The floodplain wetlands in the middle Yangtze region are biodiversity hotspots, particularly important for wintering migratory waterbirds. In recent years, extremely low winter water level events frequently occurred in the middle Yangtze River. The hydrological droughts greatly impacted the development and distribution of the wet meadows, one of the most important ecological components in the floodplains, which is vital for the survival of many migratory waterbirds wintering in the Yangtze region. To effectively manage the wet meadows, it is critical to pinpoint the drivers for their deterioration. In this study, we assessed the effects of hydrological connectivity on the ecological stability of wet meadow in Poyang Lake for the period of 2000 to 2016. We used the time series of MODIS EVI (Enhanced Vegetation Index as a proxy for productivity to infer the ecological stability of wet meadows in terms of resistance and resilience. Our results showed that (1 the wet meadows developed in freely connected lakes had significantly higher resilience; (2 wet meadows colonizing controlled lakes had higher resistance to water level anomalies; (3 there was no difference in the resistance to rainfall anomaly between the two types of lakes; (4 the wet meadow in freely connected lakes might approach a tipping point and a regime shift might be imminent. Our findings suggest that adaptive management at regional- (i.e., operation of Three Gorges Dam and site-scale (e.g., regulating sand mining are needed to safeguard the long-term ecological stability of the system, which in term has strong implications for local, regional and global biodiversity conservation.

  14. Effects of x-ray irradiation on mast cells and mastocalcergy in the connective tissue

    Energy Technology Data Exchange (ETDEWEB)

    Song, H. Y.; Rhee, S. J.; Son, M. H.; Choi, K. C. [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    1982-09-15

    Experiments were performed to observe the influence of x-ray irradiation on mast cells and mastocalcergy in rats. Animals were irradiated single dose of x-ray. X-ray irradiation was applied to the whole body in doses either 100 rads or 150 rads (Cobalt-60 Teletherapy Unit). One day after irradiation the rats were injected lead acetate intravenously, followed by injection of compound 48/80 in the back subcutaneously. Animals were killed by decapitation at intervals, 1 hour, 5 hours, 1 day and 6 day after subcutaneous injection. Specimens of the abdominal and back skin were fixed in alcohol formol solution and stained with the following methods; H-E for observation of pathological changes of tissues, toluidine blue for demonstration of mast cells, von Kossa-azure A for demonstration of carbonate and phosphate, and chloranilic acid for demonstration of calcium. The following conclusions were obtained. Calciphylatic wheals are large size in the control group, medium size in 100 rads irradiation group and small size in 150 rads irradiation group. In x-ray irradiation groups the number of mast cells decreases more in the 150 rads than in the 100 rads irradiation. In the 100 rads x-ray irradiation group, histochemical study of the injection sites showed that calcium impregnated to mast cell granules and connective tissue fibers in 1 days after subcutaneous injection. The morphogenesis of this calcinosis was the same in the rat of 5 hour after subcutaneous injection of the control group. Whereas, 1 day after subcutaneous injection in 150 rads x-ray irradiation group calcium deposited more slightly than other groups.

  15. Graph theoretical analysis of EEG effective connectivity in vascular dementia patients during a visual oddball task.

    Science.gov (United States)

    Wang, Chao; Xu, Jin; Zhao, Songzhen; Lou, Wutao

    2016-01-01

    The study was dedicated to investigating the change in information processing in brain networks of vascular dementia (VaD) patients during the process of decision making. EEG was recorded from 18 VaD patients and 19 healthy controls when subjects were performing a visual oddball task. The whole task was divided into several stages by using global field power analysis. In the stage related to the decision-making process, graph theoretical analysis was applied to the binary directed network derived from EEG signals at nine electrodes in the frontal, central, and parietal regions in δ (0.5-3.5Hz), θ (4-7Hz), α1 (8-10Hz), α2 (11-13Hz), and β (14-30Hz) frequency bands based on directed transfer function. A weakened outgoing information flow, a decrease in out-degree, and an increase in in-degree were found in the parietal region in VaD patients, compared to healthy controls. In VaD patients, the parietal region may also lose its hub status in brain networks. In addition, the clustering coefficient was significantly lower in VaD patients. Impairment might be present in the parietal region or its connections with other regions, and it may serve as one of the causes for cognitive decline in VaD patients. The brain networks of VaD patients were significantly altered toward random networks. The present study extended our understanding of VaD from the perspective of brain functional networks, and it provided possible interpretations for cognitive deficits in VaD patients. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  16. 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.

  17. Comparative effect of implant-abutment connections, abutment angulations, and screw lengths on preloaded abutment screw using three-dimensional finite element analysis: An in vitro study

    Directory of Open Access Journals (Sweden)

    Krishna Chaitanya Kanneganti

    2018-01-01

    Conclusions: The present study suggests selecting appropriate implant-abutment connection based on the abutment angulation, as well as preferring long screws with more number of threads for effective preload retention by the screws.

  18. Context-specific differences in fronto-parieto-occipital effective connectivity during short-term memory maintenance.

    Science.gov (United States)

    Kundu, Bornali; Chang, Jui-Yang; Postle, Bradley R; Van Veen, Barry D

    2015-07-01

    Although visual short-term memory (VSTM) performance has been hypothesized to rely on two distinct mechanisms, capacity and filtering, the two have not been dissociated using network-level causality measures. Here, we hypothesized that behavioral tasks challenging capacity or distraction filtering would both engage a common network of areas, namely dorsolateral prefrontal cortex (dlPFC), superior parietal lobule (SPL), and occipital cortex, but would do so according to dissociable patterns of effective connectivity. We tested this by estimating directed connectivity between areas using conditional Granger causality (cGC). Consistent with our prediction, the results indicated that increasing mnemonic load (capacity) increased the top-down drive from dlPFC to SPL, and cGC in the alpha (8-14Hz) frequency range was a predominant component of this effect. The presence of distraction during encoding (filtering), in contrast, was associated with increased top-down drive from dlPFC to occipital cortices directly and from SPL to occipital cortices directly, in both cases in the beta (15-25Hz) range. Thus, although a common anatomical network may serve VSTM in different contexts, it does so via specific functions that are carried out within distinct, dynamically configured frequency channels. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Workforce development and effective evaluation of projects.

    Science.gov (United States)

    Dickerson, Claire; Green, Tess; Blass, Eddie

    The success of a project or programme is typically determined in relation to outputs. However, there is a commitment among UK public services to spending public funds efficiently and on activities that provide the greatest benefit to society. Skills for Health recognised the need for a tool to manage the complex process of evaluating project benefits. An integrated evaluation framework was developed to help practitioners identify, describe, measure and evaluate the benefits of workforce development projects. Practitioners tested the framework on projects within three NHS trusts and provided valuable feedback to support its development. The prospective approach taken to identify benefits and collect baseline data to support evaluation was positively received and the clarity and completeness of the framework, as well as the relevance of the questions, were commended. Users reported that the framework was difficult to complete; an online version could be developed, which might help to improve usability. Effective implementation of this approach will depend on the quality and usability of the framework, the willingness of organisations to implement it, and the presence or establishment of an effective change management culture.

  20. An Evaluation of Effective Communication Skills Coursebook

    Directory of Open Access Journals (Sweden)

    Shameem Ahmed

    2016-06-01

    Full Text Available In Communicative Language Teaching situation, role of material is not only important but also inevitable. In the traditional context of English teaching textbooks are considered the main source of materials. This paper will provide an evaluation of Effective Communication Skills (ECS coursebook that has been introduced as a pilot project implemented in 2011 by the Ministry of Higher Education, Malaysia. For the current study, data has been collected on the basis of materials study, and questionnaires. The qualitative analysis has been conducted with a total sample of around 214 students, and 3 instructors. The results show that in spite of some shortcomings, there is a general satisfaction about this textbook as it is exclusively produced by the local experts for the tertiary level. The study concludes with suggestions and recommendations for the improvement of the Effective Communication Skills. Keywords: Coursebook evaluation, communicative English, Pilot Project, ECS

  1. "There is a chain of connections": using syndemics theory to understand HIV treatment side effects.

    Science.gov (United States)

    Gagnon, Marilou

    2018-07-01

    Side effects are central to the experience of living longer with HIV but rarely have they been studied alone. Unlike other aspects of that experience, like quality of life, treatment adherence, chronicity, episodic disability, aging, health, and viral load suppression, side effects have not benefited from the same level of empirical and theoretical engagement from qualitative researchers. In this paper, we draw on syndemics theory and 50 qualitative interviews to better understand the experience of HIV treatment side effects. Two main categories were identified in the data: side effects as a product and side effects as a risk factor. The first category suggests that side effects are not just the product of taking antiretroviral drugs. They are also the product of particular conditions and tend to cluster with other health problems. The second category puts forward the idea that side effects can act as a syndemic risk factor by exposing PLWH to a greater risk of developing health problems and creating conditions in which psychosocial issues are more likely to emerge. The paper concludes by calling for more research on the complex nature of side effects and for the development of comprehensive approaches for the assessment and management of side effects.

  2. An Evaluation of Effective Communication Skills Coursebook

    OpenAIRE

    Shameem Ahmed

    2016-01-01

    In Communicative Language Teaching situation, role of material is not only important but also inevitable. In the traditional context of English teaching textbooks are considered the main source of materials. This paper will provide an evaluation of Effective Communication Skills (ECS) coursebook that has been introduced as a pilot project implemented in 2011 by the Ministry of Higher Education, Malaysia. For the current study, data has been collected on the basis of materials study, and quest...

  3. Order effect in interactive information retrieval evaluation

    DEFF Research Database (Denmark)

    Clemmensen, Melanie Landvad; Borlund, Pia

    2016-01-01

    , and the good-subject effect shed light on how and why order effect may affect test participants’ IR system interaction and search behaviour. Research limitations/implications – Insight about order effect has implications for test design of IIR studies and hence the knowledge base generated on the basis...... of such studies. Due to the limited sample of 20 test participants (Library and Information Science (LIS) students) inference statistics is not applicable; hence conclusions can be drawn from this sample of test participants only. Originality/value – Only few studies in LIS focus on order effect and none from...... the perspective of IIR. Keywords Evaluation, Research methods, Information retrieval, User studies, Searching, Information searches...

  4. Evaluation of camouflage effectiveness using hyperspectral images

    Science.gov (United States)

    Zavvartorbati, Ahmad; Dehghani, Hamid; Rashidi, Ali Jabar

    2017-10-01

    Recent advances in camouflage engineering have made it more difficult to detect targets. Assessing the effectiveness of camouflage against different target detection methods leads to identifying the strengths and weaknesses of camouflage designs. One of the target detection methods is to analyze the content of the scene using remote sensing hyperspectral images. In the process of evaluating camouflage designs, there must be comprehensive and efficient evaluation criteria. Three parameters were considered as the main factors affecting the target detection and based on these factors, camouflage effectiveness assessment criteria were proposed. To combine the criteria in the form of a single equation, the equation used in target visual search models was employed and for determining the criteria, a model was presented based on the structure of the computational visual attention systems. Also, in software implementations on the HyMap hyperspectral image, a variety of camouflage levels were created for the real targets in the image. Assessing the camouflage levels using the proposed criteria, comparing and analyzing the results can show that the provided criteria and model are effective for the evaluation of camouflage designs using hyperspectral images.

  5. Landscape Distance and Connectivity Effects on Pollination of Passiflora incarnata L.

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, A.F.

    2000-05-05

    To test the effect of landscape distance and habitat corridors on pollen-mediated gene flow between fragmentary plant populations, principle investigator used fluorescent dye as a pollen analog, unique tags on pollinators and known allozyme markers using experimental and wildtype Passiflora incarnata at Savannah River Site. Results indicate no significant effect of a corridor on pollen-mediated gene flow.

  6. Connection between effective-range expansion and nuclear vertex constant or asymptotic normalization coefficient

    International Nuclear Information System (INIS)

    Yarmukhamedov, R.; Baye, D.

    2011-01-01

    Explicit relations between the effective-range expansion and the nuclear vertex constant or asymptotic normalization coefficient (ANC) for the virtual decay B→A+a are derived for an arbitrary orbital momentum together with the corresponding location condition for the (A+a) bound-state energy. They are valid both for the charged case and for the neutral case. Combining these relations with the standard effective-range function up to order six makes it possible to reduce to two the number of free effective-range parameters if an ANC value is known from experiment. Values for the scattering length, effective range, and form parameter are determined in this way for the 16 O+p, α+t, and α+ 3 He collisions in partial waves where a bound state exists by using available ANCs deduced from experiments. The resulting effective-range expansions for these collisions are valid up to energies larger than 5 MeV.

  7. [Effect of pneumatic compression in connection with ergotherapeutic treatment of Colles' fracture. A clinical controlled trial].

    Science.gov (United States)

    Svensson, B H; Frellsen, M B; Basse, P N; Bliddal, H; Caspers, J; Parby, K

    1993-02-15

    We followed forty women with functional deficits in the wrist and hand after sustaining a Colles' fracture. The women participated in occupational therapy three times a week for three weeks. At the initial evaluation, after three weeks, and at a three month evaluation, we measured the following: range of joint movement, grip strength, hand volume (oedema), pain and ADL. There was significant improvement in most of the parameters measured after three weeks of occupational therapy, with a less significant improvement from three weeks to three months. Seventeen of the forty women received twenty minutes of intermittent pneumatic compression before occupational therapy. These patients showed significant improvement in wrist extension, compared with the control group of twenty-three patients. Occupational therapy is recommended for patients showing a functional deficit after Colles' fracture. Intermittent pneumatic compression is recommended as a supplement to occupational therapy.

  8. Environmental effects on metal structures and connection in NFS waste tanks

    International Nuclear Information System (INIS)

    1977-12-01

    The integrity of the existing NFS high-level waste tanks was evaluated, based upon information available in the literature. Failure modes were identified and analyzed. The occurrence of stress-corrosion cracking (SCC) was established as the most probable failure mechanism. Factors that would minimize the occurrence of SCC were identified as post-welding stress relief and control of the NO - 3 -to-NO - 2 ratio within the waste

  9. Effects of enhanced hydrological connectivity on Mediterranean salt marsh fish assemblages with emphasis on the endangered Spanish toothcarp (Aphanius iberus

    Directory of Open Access Journals (Sweden)

    Patricia Prado

    2017-02-01

    Full Text Available The hydrological connectivity between the salt marsh and the sea was partially restored in a Mediterranean wetland containing isolated ponds resulting from former salt extraction and aquaculture activities. A preliminary assessment provided evidence that ponds farther from the sea hosted very large numbers of the endangered Spanish toothcarp, Aphanius iberus, suggesting that individuals had been trapped and consequently reach unnaturally high densities. In order to achieve both habitat rehabilitation and toothcarp conservation, efforts were made to create a gradient of hydrologically connected areas, including isolated fish reservoirs, semi-isolated, and connected salt marsh-sea areas that could allow migratory movements of fish and provide some protection for A. iberus. The fish community was monitored prior to, and for three years after rehabilitation. Results showed an increase in the number of fish species within semi-isolated areas (Zone A, whereas areas adjacent to the sea (Zone B increased the number of marine species and decreased that of estuarine species (ES. Yet overall differences in fish assemblages were much higher between zones than among study years. Generalized linear models (GLMs evidenced that distance to the sea was the most important variable explaining the local diversity of the fish community after restoration, with occasional influence of other factors such as temperature, and depth. The abundance of A. iberus was consistently higher in semi-isolated areas at greater distances from the sea, but a decline occurred in both zones and in isolated reservoir ponds after restoration efforts, which may be attributable to interannual differences in recruitment success and, to a lesser extent, to dispersal into adjacent habitats. A negative effect of restoration works on fish population cannot be excluded, but the final outcome of the intervention likely needs a longer period.

  10. The Effects of Long Duration Bed Rest on Functional Mobility and Balance: Relationship to Resting State Motor Cortex Connectivity

    Science.gov (United States)

    Erdeniz, B.; Koppelmans, V.; Bloomberg, J. J.; Kofman, I. S.; DeDios, Y. E.; Riascos-Castaneda, R. F.; Wood, S. J.; Mulavara, A. P.; Seidler, R. D.

    2014-01-01

    NASA offers researchers from a variety of backgrounds the opportunity to study bed rest as an experimental analog for space flight. Extended exposure to a head-down tilt position during long duration bed rest can resemble many of the effects of a low-gravity environment such as reduced sensory inputs, body unloading and increased cephalic fluid distribution. The aim of our study is to a) identify changes in brain function that occur with prolonged bed rest and characterize their recovery time course; b) assess whether and how these changes impact behavioral and neurocognitive performance. Thus far, we completed data collection from six participants that include task based and resting state fMRI. The data have been acquired through the bed rest facility located at the University of Texas Medical Branch (Galveston, TX). Subjects remained in bed with their heads tilted down 6 degrees below their feet for 70 consecutive days. Behavioral measures and neuroimaging assessments were obtained at seven time points: a) 7 and 12 days before bed rest; b) 7, 30, and 65 days during bed rest; and c) 7 and 12 days after bed rest. Functional connectivity magnetic resonance imaging (FcMRI) analysis was performed to assess the connectivity of motor cortex in and out of bed rest. We found a decrease in motor cortex connectivity with vestibular cortex and the cerebellum from pre bed rest to in bed rest. We also used a battery of behavioral measures including the functional mobility test and computerized dynamic posturography collected before and after bed rest. We will report the preliminary results of analyses relating brain and behavior changes. Furthermore, we will also report the preliminary results of a spatial working memory task and vestibular stimulation during in and out of bed rest.

  11. Effect of brain- and tumor-derived connective tissue growth factor on glioma invasion.

    Science.gov (United States)

    Edwards, Lincoln A; Woolard, Kevin; Son, Myung Jin; Li, Aiguo; Lee, Jeongwu; Ene, Chibawanye; Mantey, Samuel A; Maric, Dragan; Song, Hua; Belova, Galina; Jensen, Robert T; Zhang, Wei; Fine, Howard A

    2011-08-03

    Tumor cell invasion is the principal cause of treatment failure and death among patients with malignant gliomas. Connective tissue growth factor (CTGF) has been previously implicated in cancer metastasis and invasion in various tumors. We explored the mechanism of CTGF-mediated glioma cell infiltration and examined potential therapeutic targets. Highly infiltrative patient-derived glioma tumor-initiating or tumor stem cells (TIC/TSCs) were harvested and used to explore a CTGF-induced signal transduction pathway via luciferase reporter assays, chromatin immunoprecipitation (ChIP), real-time polymerase chain reaction, and immunoblotting. Treatment of TIC/TSCs with small-molecule inhibitors targeting integrin β1 (ITGB1) and the tyrosine kinase receptor type A (TrkA), and short hairpin RNAs targeting CTGF directly were used to reduce the levels of key protein components of CTGF-induced cancer infiltration. TIC/TSC infiltration was examined in real-time cell migration and invasion assays in vitro and by immunohistochemistry and in situ hybridization in TIC/TSC orthotopic xenograft mouse models (n = 30; six mice per group). All statistical tests were two-sided. Treatment of TIC/TSCs with CTGF resulted in CTGF binding to ITGB1-TrkA receptor complexes and nuclear factor kappa B (NF-κB) transcriptional activation as measured by luciferase reporter assays (mean relative luciferase activity, untreated vs CTGF(200 ng/mL): 0.53 vs 1.87, difference = 1.34, 95% confidence interval [CI] = 0.69 to 2, P < .001). NF-κB activation resulted in binding of ZEB-1 to the E-cadherin promoter as demonstrated by ChIP analysis with subsequent E-cadherin suppression (fold increase in ZEB-1 binding to the E-cadherin promoter region: untreated + ZEB-1 antibody vs CTGF(200 ng/mL) + ZEB-1 antibody: 1.5 vs 6.4, difference = 4.9, 95% CI = 4.8 to 5.0, P < .001). Immunohistochemistry and in situ hybridization revealed that TrkA is selectively expressed in the most infiltrative glioma cells in situ

  12. The Salience Network and Its Functional Architecture in a Perceptual Decision: An Effective Connectivity Study.

    Science.gov (United States)

    Lamichhane, Bidhan; Dhamala, Mukesh

    2015-08-01

    The anterior insulae (INSs) are involved in accumulating sensory evidence in perceptual decision-making independent of the motor response, whereas the dorsal anterior cingulate cortex (dACC) is known to play a role in choosing appropriate behavioral responses. Recent evidence suggests that INSs and dACC are part of the salience network (SN), a key network known to be involved in decision-making and thought to be important for the coordination of behavioral responses. However, how these nodes in the SN contribute to the decision-making process from segregation of stimuli to the generation of an appropriate behavioral response remains unknown. In this study, the authors scanned 33 participants in functional magnetic resonance imaging and asked them to decide whether the presented pairs of audio (a beep of sound) and visual (a flash of light) stimuli were synchronous or asynchronous. Participants reported their perception with a button press. Stimuli were presented in block of eight pairs with a temporal lag (ΔT) between the first (audio) and the second (visual) stimulus in each pair. They used dynamic causal modeling (DCM) and the Bayesian model evidence technique to elucidate the functional architecture between the nodes of SN. Both the synchrony and the asynchrony perception resulted in strong activation in the SN. Most importantly, the DCM analyses demonstrated that the INSs were integrating as well as driving hubs in the SN. The INSs were found to a play an important role in the integration of sensory information; input to the SN is most likely through INSs. Furthermore, significant INSs to dACC intrinsic connectivity established by these task conditions help us conclude that INSs drive the dACC to guide the behavior of choosing the appropriate response. The authors therefore argue that the dACC and INS are part of a system involved in the decision-making process from perception to planning of a motor response, and that this observed functional mechanism might

  13. Making connections

    NARCIS (Netherlands)

    Marion Duimel

    2007-01-01

    Original title: Verbinding maken; senioren en internet. More and more older people are finding their way to the Internet. Many people aged over 50 who have only recently gone online say that a new world has opened up for them. By connecting to the Internet they have the feeling that they

  14. CMS Connect

    Science.gov (United States)

    Balcas, J.; Bockelman, B.; Gardner, R., Jr.; Hurtado Anampa, K.; Jayatilaka, B.; Aftab Khan, F.; Lannon, K.; Larson, K.; Letts, J.; Marra Da Silva, J.; Mascheroni, M.; Mason, D.; Perez-Calero Yzquierdo, A.; Tiradani, A.

    2017-10-01

    The CMS experiment collects and analyzes large amounts of data coming from high energy particle collisions produced by the Large Hadron Collider (LHC) at CERN. This involves a huge amount of real and simulated data processing that needs to be handled in batch-oriented platforms. The CMS Global Pool of computing resources provide +100K dedicated CPU cores and another 50K to 100K CPU cores from opportunistic resources for these kind of tasks and even though production and event processing analysis workflows are already managed by existing tools, there is still a lack of support to submit final stage condor-like analysis jobs familiar to Tier-3 or local Computing Facilities users into these distributed resources in an integrated (with other CMS services) and friendly way. CMS Connect is a set of computing tools and services designed to augment existing services in the CMS Physics community focusing on these kind of condor analysis jobs. It is based on the CI-Connect platform developed by the Open Science Grid and uses the CMS GlideInWMS infrastructure to transparently plug CMS global grid resources into a virtual pool accessed via a single submission machine. This paper describes the specific developments and deployment of CMS Connect beyond the CI-Connect platform in order to integrate the service with CMS specific needs, including specific Site submission, accounting of jobs and automated reporting to standard CMS monitoring resources in an effortless way to their users.

  15. [Effect of water conservancy schistosomiasis control projects combined with molluscicide to control Oncomelania hupensis snails in rivers connecting with Yangtze River in Pukou District, Nanjing City].

    Science.gov (United States)

    Qiang, Zhou; Li-Xin, Wan; De-Rong, Hang; Qi-Hui, You; Jun, You; Yu-Lin, Zhang; Zhao-Feng, Zhu; Yi-Xin, Huang

    2017-12-07

    To evaluate the effect of the water conservancy schistosomiasis control projects combined with molluscicide to control Oncomelania hupensis snails in the rivers connecting with the Yangtze River. The water conservancy schistosomiasis control projects of Zhujiashan River, Qili River and Gaowang River were chosen as the study objects in Pukou District, Nanjing City. The data review method and field investigation were used to evaluate the effect of the water conservancy schistosomiasis control projects combined with molluscicide to control O. hupensis snails. After the projects of the water level control and concrete slope protection and mollusciciding were implemented, the snails in the project river sections were completely eliminated. The snail diffusion did not happen in the inland irrigation area too. In the outside of the river beach, though the snails still existed, the snail densities plunged below 1.0 snail per 1.0 m 2 . The comprehensive measures of the combination of water level control, concrete slope protection and mollusciciding can effectively control and eliminate the snails, and prevent the snails from spreading.

  16. Test-retest reliability of prefrontal transcranial Direct Current Stimulation (tDCS) effects on functional MRI connectivity in healthy subjects.

    Science.gov (United States)

    Wörsching, Jana; Padberg, Frank; Helbich, Konstantin; Hasan, Alkomiet; Koch, Lena; Goerigk, Stephan; Stoecklein, Sophia; Ertl-Wagner, Birgit; Keeser, Daniel

    2017-07-15

    Transcranial Direct Current Stimulation (tDCS) of the prefrontal cortex (PFC) can be used for probing functional brain connectivity and meets general interest as novel therapeutic intervention in psychiatric and neurological disorders. Along with a more extensive use, it is important to understand the interplay between neural systems and stimulation protocols requiring basic methodological work. Here, we examined the test-retest (TRT) characteristics of tDCS-induced modulations in resting-state functional-connectivity MRI (RS fcMRI). Twenty healthy subjects received 20minutes of either active or sham tDCS of the dorsolateral PFC (2mA, anode over F3 and cathode over F4, international 10-20 system), preceded and ensued by a RS fcMRI (10minutes each). All subject underwent three tDCS sessions with one-week intervals in between. Effects of tDCS on RS fcMRI were determined at an individual as well as at a group level using both ROI-based and independent-component analyses (ICA). To evaluate the TRT reliability of individual active-tDCS and sham effects on RS fcMRI, voxel-wise intra-class correlation coefficients (ICC) of post-tDCS maps between testing sessions were calculated. For both approaches, results revealed low reliability of RS fcMRI after active tDCS (ICC (2,1) = -0.09 - 0.16). Reliability of RS fcMRI (baselines only) was low to moderate for ROI-derived (ICC (2,1) = 0.13 - 0.50) and low for ICA-derived connectivity (ICC (2,1) = 0.19 - 0.34). Thus, for ROI-based analyses, the distribution of voxel-wise ICC was shifted to lower TRT reliability after active, but not after sham tDCS, for which the distribution was similar to baseline. The intra-individual variation observed here resembles variability of tDCS effects in motor regions and may be one reason why in this study robust tDCS effects at a group level were missing. The data can be used for appropriately designing large scale studies investigating methodological issues such as sources of variability and

  17. 78 FR 55684 - ConnectED Workshop

    Science.gov (United States)

    2013-09-11

    ... tools move everything from homework assignments to testing into the cloud. The workshop will explore possible strategies to connect virtually all of our students to next-generation broadband in a timely, cost-effective way. It will also share promising practices, from NTIA's Broadband Technology Opportunities...

  18. Effects of silicon carbide MOSFETs on the efficiency and power quality of a microgrid-connected inverter

    International Nuclear Information System (INIS)

    Ding, Xiaofeng; Chen, Feida; Du, Min; Guo, Hong; Ren, Suping

    2017-01-01

    Highlights: •The characteristics comparison between SiC-inverter and Si-inverter is implemented, considering thermal effects. •The voltage distortion of inverters is modeling from the perspective of the behaviors of the device. •The efficiency of the microgrid-connected inverter has been greatly increased by replacing Si with SiC. •The SiC microgrid-connected inverter has smaller voltage distortion and less harmonic current than those of Si-inverter. •The proposed analytical model has been validated by the experimental test. -- Abstract: With the expanding power demands and increasing use of renewable energy resources, microgrids have been widely supported. Wide bandgap semiconductor devices with higher blocking voltage capabilities and higher switching speeds, such as silicon carbide (SiC) devices, will become a critical component in building microgrids. This paper describes a comprehensive investigation of the effects of SiC Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) on the efficiency and power quality of the inverters used in low voltage microgrids compared with conventional inverters based on silicon (Si) Insulated-gate Bipolar Transistors (IGBTs). First, the characteristics of both SiC and Si are measured by a double pulse test (DPT), considering thermal effects. Then, conduction and switching losses under different temperatures are calculated based on DPT results. Second, phase voltage distortions are modeled and calculated according to the tested switching and conduction characteristics of SiC, resulting in harmonic components in the phase current. Finally, an experiment is implemented. The experimental results show that the SiC-inverter greatly increases the energy efficiency and improves the power quality in the microgrid; these results are consistent with the analytical results.

  19. Using ENLIL and SEPMOD to Evaluate Shock Connectivity Influences on Gradual SEP Events Observed with STEREO and ACE

    Science.gov (United States)

    Luhmann, J. G.; Mays, M. L.; Li, Y.; Bain, H. M.; Lee, C. O.; Odstrcil, D.; Mewaldt, R. A.; Cohen, C.; Leske, R. A.

    2017-12-01

    An observer's magnetic field connection to a SEP-producing interplanetary shock (or compression) source often appears to provide a good indicator of whether or not a SEP event occurs. As a result, some tools for SEP event modeling make use of this finding. However, a key assumption of these approaches is that the interplanetary magnetic field and heliospheric shock geometries are known throughout the event(s). We consider examples of SEP time profile calculations obtained with combined ENLIL and SEPMOD modeling where the results compare well with observations at multiple inner heliosphere sites, and compare them to cases where such comparisons show a relative lack of agreement. ENLIL does not include the shock inside 21 Rs or CME/ICME ejecta magnetic fields, but for the agreeable cases this does not seem to make a big difference. The number, size, speed and directions of related CMEs/ICMEs, and ENLIL field line geometry appear to play the most critical roles. This includes the inclusion of prior and parallel events that affect both the ICME propagation and magnetic field geometry and strength along the observer field line. It seems clear that if a SEP forecasting system is desired, we must continue to have instrumentation that allows us to specify global CME/ICME initiation geometry (coronagraphs, XUV/EUV imagers) and background solar wind structure (magnetographs).

  20. An evaluation of the 'Yaka Ŋarali'' Tackling Indigenous Smoking program in East Arnhem Land: Yolŋu people and their connection to ŋarali'.

    Science.gov (United States)

    Tane, Moana P; Hefler, Marita; Thomas, David P

    2018-04-01

    Smoking prevalence estimated between 65% and 84% has been reported among the Yolŋu peoples of East Arnhem Land, Northern Territory. We report on findings of an evaluation of the Yaka Ŋarali' Tackling Indigenous Smoking program in East Arnhem Land. Qualitative interviews with Yolŋu (N = 23) and non-Yolŋu (N = 7) informants were conducted in seven communities between June 2014 and September 2015, with the support of Cultural Mentors, in homeland communities throughout East Arnhem Land. The data was coded using NVivo software, analysed line-by-line and categorised by the researcher (MT) under three a priori categories established as evaluation parameters. In addition, the meanings of ŋarali' and Yolŋu cultural obligations to ŋarali' were analysed using an inductive process. Data were coded under three a priori themes: Yolŋu trying to quit smoking (interest in quitting, access to support); the Yaka Ŋarali program (efficacy and recognition); Yolŋu workforce (roles and responsibilities). Yolŋu informants, including Elders and leaders, both smokers and non-smokers uniformly acknowledged the deep cultural and traditional connection with ŋarali' attributing this relationship with its introduction by the Macassans and its subsequent adoption into ceremony. Given the strong cultural and traditional connection to ŋarali', care must be taken to ensure tobacco control measures maintain congruence with local values and expectations. SO WHAT?: Tailored, localised programs, developed in consultation with communities, Elders and leaders are needed to respect and accommodate the tight connection that the Yolŋu have with ŋarali', maintained over hundreds of years. © 2017 Australian Health Promotion Association.

  1. Effect of differences in gas-dynamic behaviour on the separation performance of ultracentrifuges connected in parallel

    International Nuclear Information System (INIS)

    Portoghese, C.C.P.; Buchmann, J.H.

    1996-01-01

    This paper is concerned with the degradation of separation factors occurred when groups of ultracentrifuges having different gas-dynamic behaviour are connected in parallel arrangements. Differences in the gas-dynamic behavior were traduced in terms of different tails pressures for the same operational conditions, that are feed flow rate, product pressure and cut number. A mathematical model describing the ratio of the tails flow rates as a function of the tails pressure ratios and the feed flow rate was developed using experimental data collected from a pair of different ultracentrifuges connected in parallel. The optimization of model parameters was made using Marquardt's algorithm. The model developed was used to simulate the separation factors degradation in some parallel arrangements containing more than two centrifuges. Te obtained results were compared with experimental data collected from different groups of ultracentrifuges. It was observed that the calculated results were in good agreement with experimental data. This mathematical model, which parameters were determined in a two-centrifuges parallel arrangement, is useful to simulate the effect of quantified gas-dynamic differences in the separation factors of groups containing any number of different ultracentrifuges and, consequently, to analyze cascade losses due to this kind of occurrence. (author)

  2. Activity in dlPFC and its effective connectivity to vmPFC are associated with temporal discounting

    Directory of Open Access Journals (Sweden)

    Todd A Hare

    2014-03-01

    Full Text Available There is widespread interest in identifying computational and neurobiological mechanisms that influence the ability to choose long-term benefits over more proximal and readily available rewards in domains such as dietary and economic choice. We present the results of a human fMRI study that examines how neural activity relates to observed individual differences in the discounting of future rewards during an intertemporal monetary choice task. We found that a region of left dlPFC BA-46 was more active in trials where subjects chose delayed rewards, after controlling for the subjective value of those rewards. We also found that the connectivity from dlPFC BA-46 to a region of vmPFC widely associated with the computational of stimulus values, increased at the time of choice, and especially during trials in which subjects chose delayed rewards. Finally, we found that estimates of effective connectivity between these two regions played a critical role in predicting out-of-sample, between-subject differences in discount rates. Together with previous findings in dietary choice, these results suggest that a common set of computational and neurobiological mechanisms facilitate choices in favor of long- term reward in both settings.

  3. Mode of effective connectivity within a putative neural network differentiates moral cognitions related to care and justice ethics.

    Science.gov (United States)

    Cáceda, Ricardo; James, G Andrew; Ely, Timothy D; Snarey, John; Kilts, Clinton D

    2011-02-25

    Moral sensitivity refers to the interpretive awareness of moral conflict and can be justice or care oriented. Justice ethics is associated primarily with human rights and the application of moral rules, whereas care ethics is related to human needs and a situational approach involving social emotions. Among the core brain regions involved in moral issue processing are: medial prefrontal cortex, anterior (ACC) and posterior (PCC) cingulate cortex, posterior superior temporal sulcus (pSTS), insula and amygdala. This study sought to inform the long standing debate of whether care and justice moral ethics represent one or two different forms of cognition. Model-free and model-based connectivity analysis were used to identify functional neural networks underlying care and justice ethics for a moral sensitivity task. In addition to modest differences in patterns of associated neural activity, distinct modes of functional and effective connectivity were observed for moral sensitivity for care and justice issues that were modulated by individual variation in moral ability. These results support a neurobiological differentiation between care and justice ethics and suggest that human moral behavior reflects the outcome of integrating opposing rule-based, self-other perspectives, and emotional responses.

  4. Mode of Effective Connectivity within a Putative Neural Network Differentiates Moral Cognitions Related to Care and Justice Ethics

    Science.gov (United States)

    Cáceda, Ricardo; James, G. Andrew; Ely, Timothy D.; Snarey, John; Kilts, Clinton D.

    2011-01-01

    Background Moral sensitivity refers to the interpretive awareness of moral conflict and can be justice or care oriented. Justice ethics is associated primarily with human rights and the application of moral rules, whereas care ethics is related to human needs and a situational approach involving social emotions. Among the core brain regions involved in moral issue processing are: medial prefrontal cortex, anterior (ACC) and posterior (PCC) cingulate cortex, posterior superior temporal sulcus (pSTS), insula and amygdala. This study sought to inform the long standing debate of whether care and justice moral ethics represent one or two different forms of cognition. Methodology/Principal Findings Model-free and model-based connectivity analysis were used to identify functional neural networks underlying care and justice ethics for a moral sensitivity task. In addition to modest differences in patterns of associated neural activity, distinct modes of functional and effective connectivity were observed for moral sensitivity for care and justice issues that were modulated by individual variation in moral ability. Conclusions/Significance These results support a neurobiological differentiation between care and justice ethics and suggest that human moral behavior reflects the outcome of integrating opposing rule-based, self-other perspectives, and emotional responses. PMID:21364916

  5. Mode of effective connectivity within a putative neural network differentiates moral cognitions related to care and justice ethics.

    Directory of Open Access Journals (Sweden)

    Ricardo Cáceda

    Full Text Available BACKGROUND: Moral sensitivity refers to the interpretive awareness of moral conflict and can be justice or care oriented. Justice ethics is associated primarily with human rights and the application of moral rules, whereas care ethics is related to human needs and a situational approach involving social emotions. Among the core brain regions involved in moral issue processing are: medial prefrontal cortex, anterior (ACC and posterior (PCC cingulate cortex, posterior superior temporal sulcus (pSTS, insula and amygdala. This study sought to inform the long standing debate of whether care and justice moral ethics represent one or two different forms of cognition. METHODOLOGY/PRINCIPAL FINDINGS: Model-free and model-based connectivity analysis were used to identify functional neural networks underlying care and justice ethics for a moral sensitivity task. In addition to modest differences in patterns of associated neural activity, distinct modes of functional and effective connectivity were observed for moral sensitivity for care and justice issues that were modulated by individual variation in moral ability. CONCLUSIONS/SIGNIFICANCE: These results support a neurobiological differentiation between care and justice ethics and suggest that human moral behavior reflects the outcome of integrating opposing rule-based, self-other perspectives, and emotional responses.

  6. Sample heterogeneity in unipolar depression as assessed by functional connectivity analyses is dominated by general disease effects.

    Science.gov (United States)

    Feder, Stephan; Sundermann, Benedikt; Wersching, Heike; Teuber, Anja; Kugel, Harald; Teismann, Henning; Heindel, Walter; Berger, Klaus; Pfleiderer, Bettina

    2017-11-01

    Combinations of resting-state fMRI and machine-learning techniques are increasingly employed to develop diagnostic models for mental disorders. However, little is known about the neurobiological heterogeneity of depression and diagnostic machine learning has mainly been tested in homogeneous samples. Our main objective was to explore the inherent structure of a diverse unipolar depression sample. The secondary objective was to assess, if such information can improve diagnostic classification. We analyzed data from 360 patients with unipolar depression and 360 non-depressed population controls, who were subdivided into two independent subsets. Cluster analyses (unsupervised learning) of functional connectivity were used to generate hypotheses about potential patient subgroups from the first subset. The relationship of clusters with demographical and clinical measures was assessed. Subsequently, diagnostic classifiers (supervised learning), which incorporated information about these putative depression subgroups, were trained. Exploratory cluster analyses revealed two weakly separable subgroups of depressed patients. These subgroups differed in the average duration of depression and in the proportion of patients with concurrently severe depression and anxiety symptoms. The diagnostic classification models performed at chance level. It remains unresolved, if subgroups represent distinct biological subtypes, variability of continuous clinical variables or in part an overfitting of sparsely structured data. Functional connectivity in unipolar depression is associated with general disease effects. Cluster analyses provide hypotheses about potential depression subtypes. Diagnostic models did not benefit from this additional information regarding heterogeneity. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Empirical evaluation of augmented prototyping effectiveness

    Directory of Open Access Journals (Sweden)

    Tomáš Koubek

    2012-01-01

    Full Text Available Augmented reality is a scientific field well known for more than twenty years. Although there is a huge number of projects that present promising results, the real usage of augmented reality applications for fulfilling common tasks is almost negligible. We believe that one of the principal reasons is insufficient usability of these applications. The situation is analogous to the desktop, mobile or cloud application development or even to the web pages design. The first phase of a technology adoption is the exploration of its potential. As soon as the technical problems are overcome and the technology is widely accepted, the usability is a principal issue. The usability is utmost important also from the business point of view. The cost of augmented reality implementation into the production process is substantial, therefore, the usability that is directly responsible for the implemented solution effectiveness must be appropriately tested. Consequently, the benefit of the implemented solution can be measured.This article briefly outlines common techniques used for usability evaluation. Discussed techniques were designed especially for evaluation of desktop applications, mobile solutions and web pages. In spite of this drawback, their application