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Sample records for activity patterns related

  1. Relative humidity and activity patterns of Ixodes scapularis (Acari: Ixodidae)

    USGS Publications Warehouse

    Berger, K.A.; Ginsberg, Howard S.; Gonzalez, L.; Mather, T.N.

    2014-01-01

    Laboratory studies have shown clear relationships between relative humidity (RH) and the activity and survival of Ixodes scapularis Say (blacklegged tick). However, field studies have produced conflicting results. We examined this relationship using weekly tick count totals and hourly RH observations at three field sites, stratified by latitude, within the state of Rhode Island. Records of nymphal tick abundance were compared with several RH-related variables (e.g., RH at time of sampling and mean weekly daytime RH). In total, 825 nymphs were sampled in 2009, a year of greater precipitation, with a weighted average leaf litter RH recorded at time of sampling of 85.22%. Alternatively, 649 nymphs were collected in 2010, a year of relatively low precipitation, and a weighted average RH recorded at time of sampling was 75.51%. Negative binomial regression analysis of tick count totals identified cumulative hours <82% RH threshold as a significant factor observed in both years (2009: P = 0.0037; 2010: P < 0.0001). Mean weekly daytime RH did not significantly predict tick activity in either year. However, mean weekly daytime RH recorded with 1-wk lag before sample date was a significant variable (P = 0.0016) in 2010. These results suggest a lag effect between moisture availability and patterns of tick activity and abundance. Differences in the relative importance of each RH variable between years may have been due to abnormally wet summer conditions in 2009.

  2. [Mammals' camera-trapping in Sierra Nanchititla, Mexico: relative abundance and activity patterns].

    PubMed

    Monroy-Vilchis, Octavio; Zarco-González, Martha M; Rodríguez-Soto, Clarita; Soria-Díaz, Leroy; Urios, Vicente

    2011-03-01

    Species conservation and their management depend on the availability of their population behavior and changes in time. This way, population studies include aspects such as species abundance and activity pattern, among others, with the advantage that nowadays new technologies can be applied, in addition to common methods. In this study, we used camera-traps to obtain the index of relative abundance and to establish activity pattern of medium and large mammals in Sierra Nanchititla, Mexico. The study was conducted from December 2003 to May 2006, with a total sampling effort of 4 305 trap-days. We obtained 897 photographs of 19 different species. Nasua narica, Sylvilagus floridanus and Urocyon cinereoargenteus were the most abundant, in agreement with the relative abundance index (RAI, number of independent records/100 trap-days), and according to previous studies with indirect methods in the area. The activity patterns of the species showed that 67% of them are nocturnal, except Odocoileus virginianus, Nasua narica and others. Some species showed differences with previously reported patterns, which are related with seasonality, resources availability, organism sex, principally. The applied method contributed with reliable data about relative abundance and activity patterns. PMID:21516657

  3. Spatiotemporal relations of primary sensorimotor and secondary motor activation patterns mapped by NIR imaging

    PubMed Central

    Khan, Bilal; Chand, Pankaj; Alexandrakis, George

    2011-01-01

    Functional near infrared (fNIR) imaging was used to identify spatiotemporal relations between spatially distinct cortical regions activated during various hand and arm motion protocols. Imaging was performed over a field of view (FOV, 12 x 8.4 cm) including the secondary motor, primary sensorimotor, and the posterior parietal cortices over a single brain hemisphere. This is a more extended FOV than typically used in current fNIR studies. Three subjects performed four motor tasks that induced activation over this extended FOV. The tasks included card flipping (pronation and supination) that, to our knowledge, has not been performed in previous functional magnetic resonance imaging (fMRI) or fNIR studies. An earlier rise and a longer duration of the hemodynamic activation response were found in tasks requiring increased physical or mental effort. Additionally, analysis of activation images by cluster component analysis (CCA) demonstrated that cortical regions can be grouped into clusters, which can be adjacent or distant from each other, that have similar temporal activation patterns depending on whether the performed motor task is guided by visual or tactile feedback. These analyses highlight the future potential of fNIR imaging to tackle clinically relevant questions regarding the spatiotemporal relations between different sensorimotor cortex regions, e.g. ones involved in the rehabilitation response to motor impairments. PMID:22162826

  4. Location, Timing, and Social Structure Patterns Related to Physical Activity Participation in Weight Loss Programs

    ERIC Educational Resources Information Center

    Gay, Jennifer L.; Trevarthen, Grace

    2013-01-01

    Less than half of the adults in the United States meet national guidelines for physical activity. Physical activity programs can induce short-term improvements in physical activity. To develop effective interventions, researchers and practitioners should consider the timing, location, and social structure patterns of participants. Using a pretest,…

  5. Seasonal activity patterns of Ixodes pacificus nymphs in relation to climatic conditions.

    PubMed

    Eisen, L; Eisen, R J; Lane, R S

    2002-09-01

    In western North America, the tick Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) is the primary vector to humans and domestic animals of the disease agents causing Lyme disease and granulocytic ehrlichiosis. We examined the seasonal activity patterns of I. pacificus nymphs over a 4-year period, including the wet and cold El Niño winter/spring of 1998, in a dry oak/madrone woodland, and for one year in a cooler and moister redwood/tanoak woodland in Mendocino County, California. Linear regressions were used to estimate when nymphal densities first exceeded and then fell below 25, 50 and 75% of the recorded yearly peak densities. In oak/madrone woodland, nymphs typically were active by mid-March, reached 50% of their yearly peak densities in early to mid-April, peaked by early May, fell below 50% of their peak densities by early to mid-June, and were absent by late July to mid-August. The lengths of the periods with nymphal densities exceeding 50 and 75% of the recorded yearly peaks in oak/madrone woodland were associated positively with rainfall and negatively with maximum air temperatures during April-May. Moreover, nymphal numbers typically reached 50% of their peak 10-15 days later, remained at levels above 50% of the peak 1.3-1.5 times longer, and started declining 4-6 weeks later under cooler, moister climatic conditions (oak/madrone woodland in 1998 and redwood/tanoak woodland in 2000) relative to warmer, drier conditions (oak/madrone woodland in 2000-2001). In oak/madrone woodland, nymphal densities typically started to decline when mean maximum daily air temperatures exceeded 23 degrees C. Nymphal densities were higher in dry oak/madrone relative to moist redwood/tanoak woodland from mid-March to late May 2000, similar in both habitat types in early June, but higher in redwood/tanoak woodland from late June onwards. We conclude that large-scale studies of the density of I. pacificus nymphs in California need to consider spatial variation in the length

  6. Patterns of neighborhood environment attributes related to physical activity across 11 countries: a latent class analysis

    PubMed Central

    2013-01-01

    Background Neighborhood environment studies of physical activity (PA) have been mainly single-country focused. The International Prevalence Study (IPS) presented a rare opportunity to examine neighborhood features across countries. The purpose of this analysis was to: 1) detect international neighborhood typologies based on participants’ response patterns to an environment survey and 2) to estimate associations between neighborhood environment patterns and PA. Methods A Latent Class Analysis (LCA) was conducted on pooled IPS adults (N=11,541) aged 18 to 64 years old (mean=37.5 ±12.8 yrs; 55.6% women) from 11 countries including Belgium, Brazil, Canada, Colombia, Hong Kong, Japan, Lithuania, New Zealand, Norway, Sweden, and the U.S. This subset used the Physical Activity Neighborhood Environment Survey (PANES) that briefly assessed 7 attributes within 10–15 minutes walk of participants’ residences, including residential density, access to shops/services, recreational facilities, public transit facilities, presence of sidewalks and bike paths, and personal safety. LCA derived meaningful subgroups from participants’ response patterns to PANES items, and participants were assigned to neighborhood types. The validated short-form International Physical Activity Questionnaire (IPAQ) measured likelihood of meeting the 150 minutes/week PA guideline. To validate derived classes, meeting the guideline either by walking or total PA was regressed on neighborhood types using a weighted generalized linear regression model, adjusting for gender, age and country. Results A 5-subgroup solution fitted the dataset and was interpretable. Neighborhood types were labeled, “Overall Activity Supportive (52% of sample)”, “High Walkable and Unsafe with Few Recreation Facilities (16%)”, “Safe with Active Transport Facilities (12%)”, “Transit and Shops Dense with Few Amenities (15%)”, and “Safe but Activity Unsupportive (5%)”. Country representation differed by

  7. Differential neural activity patterns for spatial relations in humans: a MEG study.

    PubMed

    Scott, Nicole M; Leuthold, Arthur; Sera, Maria D; Georgopoulos, Apostolos P

    2016-02-01

    Children learn the words for above-below relations earlier than for left-right relations, despite treating these equally well in a simple visual categorization task. Even as adults--conflicts in congruency, such as when a stimulus is depicted in a spatially incongruent manner with respect to salient global cues--can be challenging. Here we investigated the neural correlates of encoding and maintaining in working memory above-below and left-right relational planes in 12 adults using magnetoencephalography in order to discover whether above-below relations are represented by the brain differently than left-right relations. Adults performed perfectly on the task behaviorally, so any differences in neural activity were attributed to the stimuli's cognitive attributes. In comparing above-below to left-right relations during stimulus encoding, we found the greatest differences in neural activity in areas associated with space and movement. In comparing congruent to incongruent trials, we found the greatest differential activity in premotor areas. For both contrasts, brain areas involved in the encoding phase were also involved in the maintenance phase, which provides evidence that those brain areas are particularly important in representing the relational planes or congruency types throughout the trial. When comparing neural activity associated with the relational planes during working memory, additional right posterior areas were implicated, whereas the congruent-incongruent contrast implicated additional bilateral frontal and temporal areas. These findings are consistent with the hypothesis left-right relations are represented differently than above-below relations. PMID:26514809

  8. Highly fluorinated 2,2'-biphenols and related compounds: relationship between substitution pattern and herbicidal activity.

    PubMed

    Francke, Robert; Reingruber, Rüdiger; Schollmeyer, Dieter; Waldvogel, Siegfried R

    2013-05-22

    A broad range of halogenated 2,2'-biphenols was tested for applicability as crop protection agents. The activity of these compounds toward four typical pest plants was observed after application by spraying of diluted solutions. Despite their rather simple structure, it was found that the studied compounds reveal a surprisingly high herbicidal impact. To gain a better understanding of the structure-activity relationship, specific sites of the molecule were chemically modified and the core structures thus gradually changed. The influence of the substitution pattern on the herbicidal properties is discussed, and conclusions on the active site of the biphenol structure are drawn. It was observed that type and position of the halogen substituents have a significant influence on the activity of the core structure. The hydroxy functionalities play a crucial role for the effectiveness of the tested compounds. Because the blocking of the hydroxy moiety leads to dramatically deteriorated performances, the presence of these functionalities on the aromatic ring seems to be indispensable. PMID:23641939

  9. Physical Activity Patterns and Factors Related to Exercise during Pregnancy: A Cross Sectional Study

    PubMed Central

    Nascimento, Simony Lira; Surita, Fernanda Garanhani; Godoy, Ana Carolina; Kasawara, Karina Tamy; Morais, Sirlei Siani

    2015-01-01

    Objective To assess the physical activity levels of pregnant women and to examine the characteristics associated with the practice of exercise and the activities of daily living during pregnancy. Methods For this cross-sectional study, 1,279 women were recruited within 72 hours postpartum. They were interviewed about their socio-demographic data and obstetric history and were administered self-report questionnaires about exercise and daily physical activities during pregnancy. Data on the current pregnancy, labor, delivery, and newborn outcomes were collected from participants’ medical records. To analyze factors related to the practice of exercise, we used the student t-test, X², and odds ratio (OR), with a corresponding 95% confident interval (CI), followed by a multiple logistic regression. The significance level was 5%. Results Compared to the pre-pregnancy period, the prevalence of physical activity among participants was lower throughout pregnancy (20.1%) (p = 0.01). Half of the women interrupted practicing physical exercise due to pregnancy. The lowest prevalence of exercise was observed in the first (13.6%) and third trimesters (13.4%). Less than half of women received exercise guidance during prenatal care meetings (47.4%). Walking was the most commonly reported exercise, followed by water aerobics. Factors positively associated with exercise practice were higher educational level (OR= 1.82; CI 95% 1.28–2.60), primiparity (OR=1.49; CI 95% 1.07–2.07), exercising before pregnancy (OR= 6.45; CI 95% 4.64–8.96), and exercise guidance during prenatal care (OR=2.54; CI 95% 1.80–3.57). Mildly intense exercise and domestic activities were most frequently reported among pregnant women. There were no differences in maternal and perinatal outcomes between active and sedentary pregnant women. Conclusion The findings indicate that promoting physical activity remains a priority in public health policy, and women of childbearing age, especially those planning a

  10. Pattern of brain activation during social cognitive tasks is related to social competence in siblings discordant for schizophrenia.

    PubMed

    Villarreal, Mirta F; Drucaroff, Lucas J; Goldschmidt, Micaela G; de Achával, Delfina; Costanzo, Elsa Y; Castro, Mariana N; Ladrón-de-Guevara, M Soledad; Busatto Filho, Geraldo; Nemeroff, Charles B; Guinjoan, Salvador M

    2014-09-01

    Measures of social competence are closely related to actual community functioning in patients with schizophrenia. However, the neurobiological mechanisms underlying competence in schizophrenia are not fully understood. We hypothesized that social deficits in schizophrenia are explained, at least in part, by abnormally lateralized patterns of brain activation in response to tasks engaging social cognition, as compared to healthy individuals. We predicted such patterns would be partly heritable, and therefore affected in patients' nonpsychotic siblings as well. We used a functional magnetic resonance image paradigm to characterize brain activation induced by theory of mind tasks, and two tests of social competence, the Test of Adaptive Behavior in Schizophrenia (TABS), and the Social Skills Performance Assessment (SSPA) in siblings discordant for schizophrenia and comparable healthy controls (n = 14 per group). Healthy individuals showed the strongest correlation between social competence and activation of right hemisphere structures involved in social cognitive processing, whereas in patients, the correlation pattern was lateralized to left hemisphere areas. Unaffected siblings of patients exhibited a pattern intermediate between the other groups. These results support the hypothesis that schizophrenia may be characterized by an abnormal functioning of nondominant hemisphere structures involved in the processing of socially salient information. PMID:24927685

  11. Age-related patterns of vigorous-intensity physical activity in youth: The International Children's Accelerometry Database.

    PubMed

    Corder, Kirsten; Sharp, Stephen J; Atkin, Andrew J; Andersen, Lars B; Cardon, Greet; Page, Angie; Davey, Rachel; Grøntved, Anders; Hallal, Pedro C; Janz, Kathleen F; Kordas, Katarzyna; Kriemler, Susi; Puder, Jardena J; Sardinha, Luis B; Ekelund, Ulf; van Sluijs, Esther M F

    2016-12-01

    Physical activity declines during youth but most evidence reports on combined moderate and vigorous-intensity physical activity. We investigated how vigorous-intensity activity varies with age. Cross-sectional data from 24,025 participants (5.0-18.0 y; from 20 studies in 10 countries obtained 2008-2010) providing ≥ 1 day accelerometer data (International Children's Accelerometry Database (ICAD)). Linear regression was used to investigate age-related patterns in vigorous-intensity activity; models included age (exposure), adjustments for monitor wear-time and study. Moderate-intensity activity was examined for comparison. Interactions were used to investigate whether the age/vigorous-activity association differed by sex, weight status, ethnicity, maternal education and region. A 6.9% (95% CI 6.2, 7.5) relative reduction in mean vigorous-intensity activity with every year of age was observed; for moderate activity the relative reduction was 6.0% (5.6%, 6.4%). The age-related decrease in vigorous-intensity activity remained after adjustment for moderate activity. A larger age-related decrease in vigorous activity was observed for girls (- 10.7%) versus boys (- 2.9%), non-white (- 12.9% to - 9.4%) versus white individuals (- 6.1%), lowest maternal education (high school (- 2.0%)) versus college/university (ns) and for overweight/obese (- 6.1%) versus healthy-weight participants (- 8.1%). In addition to larger annual decreases in vigorous-intensity activity, overweight/obese individuals, girls and North Americans had comparatively lower average vigorous-intensity activity at 5.0-5.9 y. Age-related declines in vigorous-intensity activity during youth appear relatively greater than those of moderate activity. However, due to a higher baseline, absolute moderate-intensity activity decreases more than vigorous. Overweight/obese individuals, girls, and North Americans appear especially in need of vigorous-intensity activity promotion due to low levels at 5

  12. Age-related changes in trunk neuromuscular activation patterns during a controlled functional transfer task include amplitude and temporal synergies.

    PubMed

    Quirk, D Adam; Hubley-Kozey, Cheryl L

    2014-12-01

    While healthy aging is associated with physiological changes that can impair control of trunk motion, few studies examine how spinal muscle responses change with increasing age. This study examined whether older (over 65 years) compared to younger (20-45 years) adults had higher overall amplitude and altered temporal recruitment patterns of trunk musculature when performing a functional transfer task. Surface electromyograms from twelve bilateral trunk muscle (24) sites were analyzed using principal component analysis, extracting amplitude and temporal features (PCs) from electromyographic waveforms. Two PCs explained 96% of the waveform variance. Three factor ANOVA models tested main effects (group, muscle and reach) and interactions for PC scores. Significant (p<.0125) group interactions were found for all PC scores. Post hoc analysis revealed that relative to younger adults, older adults recruited higher agonist and antagonistic activity, demonstrated continuous activation levels in specific muscle sites despite changing external moments, and had altered temporal synergies within abdominal and back musculature. In summary both older and younger adults recruit highly organized activation patterns in response to changing external moments. Differences in temporal trunk musculature recruitment patterns suggest that older adults experience different dynamic spinal stiffness and loading compared to younger adults during a functional lifting task. PMID:25457424

  13. Patterns of Field Learning Activities and Their Relation to Learning Outcome

    ERIC Educational Resources Information Center

    Lee, Mingun; Fortune, Anne E.

    2013-01-01

    Field practicum is an active learning process. This study explores the different learning stages or processes students experience during their field practicum. First-year master's of social work students in field practica were asked how much they had engaged in educational learning activities such as observation, working independently,…

  14. Pattern of Classroom Activities during Students' Use of Computers: Relations between Instructional Strategies and Computer Applications

    ERIC Educational Resources Information Center

    Inan, Fethi A.; Lowther, Deborah L.; Ross, Steven M.; Strahl, Dan

    2010-01-01

    The purpose of this study was to identify instructional strategies used by teachers to support technology integration. In addition, relations between types of computer applications and teachers' classroom practices were examined. Data were direct observation results from 143 integration lessons implemented in schools receiving federal technology…

  15. Functional near infrared spectroscopy study of age-related difference in cortical activation patterns during cycling with speed feedback.

    PubMed

    Lin, Pei-Yi; Lin, Sang-I; Chen, Jia-Jin J

    2012-01-01

    Functional decline of lower-limb affects the ability of locomotion and the age-related brain differences have been elucidated among the elderly. Cycling exercise is a common training program for restoring motor function in the deconditioned elderly or stroke patients. The provision of speed feedback has been commonly suggested to clinical therapists for facilitating learning of controlled cycling performance and maintaining motivation in training programs with elderly participants. However, the cortical control of pedaling movements and the effect of external feedback remain poorly understanding. This study investigated the regional cortical activities detected by functional near infrared spectroscopy (fNIRS) in 12 healthy young and 13 healthy elderly subjects under conditions of cycling without-(free cycling) and with feedback (target cycling). The elderly exhibited predominant activation of the sensorimotor cortex during free cycling similar to young subjects but with poorer cycling performance. The cycling performance improved in both groups, and the elderly showed increased brain activities of the supplementary motor area and premotor cortex under target cycling condition. These findings demonstrated age-related changes in the cortical control in processing external feedback and pedaling movements. Use of fNIRS to evaluate brain activation patterns after training may facilitate brain-based design of tailored therapeutic rehabilitation strategies. PMID:21984524

  16. Fibrinogen-related protein from amphioxus Branchiostoma belcheri is a multivalent pattern recognition receptor with a bacteriolytic activity.

    PubMed

    Fan, Chunxin; Zhang, Shicui; Li, Lei; Chao, Yeqing

    2008-07-01

    Fibrinogen-related proteins (FREPs) containing fibrinogen-like (FBG) domain have been shown to be involved in immune responses in both invertebrates and vertebrates, but the underlying mechanisms remain ill-defined. In this study we isolated a cDNA encoding amphioxus (Branchiostoma belcheri) FREP homolog, BbFREP. BbFREP encoded a protein of 286 amino acids, which included a C-terminal FBG domain and clustered together with human fibrinogen beta and gamma chains. Quantitative real time PCR revealed that the expression of BbFREP was significantly up-regulated following challenge with lipopolysaccharides (LPS) or lipoteichoic acid (LTA). The recombinant BbFREP expressed in Pichia pastoris was able to specifically recognize the pathogen-associated molecular patterns (PAMPs) on the bacterial surfaces including LPS, peptidoglycan (PGN) and LTA, and displayed strong bacteriolytic activities against both Gram-negative bacterium Escherichia coli and Gram-positive bacterium Staphylococcus aureus. BbFREP was also able to bind to both E. coli and S. aureus. In situ hybridization indicated that BbFREP was mainly expressed in the hepatic caecum and hind-gut, agreeing basically with the primary expression of vertebrate FREP genes in the liver. All these suggest that BbFREP can function as a pattern recognition receptor with a bacteriolytic activity via interaction with LPS, LTA and PGN. It also bolsters the notion that the hepatic caecum of amphioxus is equivalent to the vertebrate liver, acting as a major tissue in acute phase response. PMID:18533266

  17. Mosaic activity patterns and their relation to perceptual similarity: open discussions on the molecular basis and circuitry of odor recognition.

    PubMed

    Locatelli, Fernando F; Rela, Lorena

    2014-12-01

    Enormous advances have been made in the recent years in regard to the mechanisms and neural circuits by which odors are sensed and perceived. Part of this understanding has been gained from parallel studies in insects and rodents that show striking similarity in the mechanisms they use to sense, encode, and perceive odors. In this review, we provide a short introduction to the functioning of olfactory systems from transduction of odorant stimuli into electrical signals in sensory neurons to the anatomical and functional organization of the networks involved in neural representation of odors in the central nervous system. We make emphasis on the functional and anatomical architecture of the first synaptic relay of the olfactory circuit, the olfactory bulb in vertebrates and the antennal lobe in insects. We discuss how the exquisite and conserved architecture of this structure is established and how different odors are encoded in mosaic activity patterns. Finally, we discuss the validity of methods used to compare activation patterns in relation to perceptual similarity. PMID:25123415

  18. Patterns in Active Nematics

    NASA Astrophysics Data System (ADS)

    Yeomans, Julia M.

    Active systems, from bacterial suspensions to cellular monolayers, are continuously driven out of equilibrium by local injection of energy from their constituent elements and exhibit turbulent-like, chaotic patterns. We describe how active systems can be stabilised by tuning a physical feature of the system, friction. We demonstrate how the crossover between wet active systems, whose behaviour is dominated by hydrodynamics, and dry active matter where any flow is screened, can be achieved by using friction as a control parameter and demonstrate vortex ordering at the wet-dry crossover. We show that the self organisation of vortices into lattices is accompanied by the spatial ordering of topological defects leading to active crystal-like structures. The emergence of vortex lattices which leads to the positional ordering of topological defects may be a useful step towards the design and control of active materials.

  19. [Relative abundance, population structure, habitat preferences and activity patterns of Tapirus bairdii (Perissodactyla: Tapiridae), in Chimalapas forest, Oaxaca, Mexico].

    PubMed

    Lira-Torres, Iván; Briones-Salas, Miguel; Sánchez-Rojas, Gerardo

    2014-12-01

    Baird's tapir (Tapirus bairdii) is endangered primarily because of habitat loss and fragmentation, and overhunting throughout its distribution range. One of the priority land areas for the conservation of this species is the Northern part of its range in the Chimalapas forest, Oaxaca. The aim of this research was to determine the relative abundance, population struc- ture, habitat preferences and activity patterns of Baird's tapir (Tapirus bairdii) in the Chimalapas forest, Oaxaca, Mexico, through the non-invasive technique of camera-trap sampling. A total of five sampling sessions were undertaken among 2009-2013, and used a total of 30 camera-traps in each period. The determinant factor of the sampling design was the hunting between two study areas. A total sampling effort of 9000 trap-days allowed to estimate an index of relative abundance (IRA) of 6.77 tapir photographs/1,000 trap-days (n = 61). IRA varied significantly between sampling stations (Mann-Whitney, p < 0.01). The frequency of Baird's tapir photos was higher in the dry season in tropical rain forest without hunting (χ2, p < 0.5). In the rainy season, the tropical rain forest and secondary vegetation habitats showed higher photo frequency than expected from random (χ2, p < 0.5). Considering population structure, a 95.08% of adult animals was obtained in photographic records (n = 58). Three types of activity pattern were observed, with more nocturnal records (88.33%; Kruskal-Wallis, p < 0.05). The Chimalapas forest appears to be the second most important terrestrial priority ecoregion, just after the Mayan Forest (Campeche, Chiapas, Quintana Roo), for the conservation of tapir populations, not only for Mexico but also for Central America. PMID:25720176

  20. Lowland tapir (Tapirus terrestris) distribution, activity patterns and relative abundance in the Greater Madidi-Tambopata Landscape.

    PubMed

    Wallace, Robert; Ayala, Guido; Viscarra, Maria

    2012-12-01

    Lowland tapir distribution is described in northwestern Bolivia and southeastern Peru within the Greater Madidi-Tambopata Landscape, a priority Tapir Conservation Unit, using 1255 distribution points derived from camera trapping efforts, field research and interviews with park guards from 5 national protected areas and hunters from 19 local communities. A total of 392 independent camera trapping events from 14 camera trap surveys at 11 sites demonstrated the nocturnal and crepuscular activity patterns (86%) of the lowland tapir and provide 3 indices of relative abundance for spatial and temporal comparison. Capture rates for lowland tapirs were not significantly different between camera trapping stations placed on river beaches versus those placed in the forest. Lowland tapir capture rates were significantly higher in the national protected areas of the region versus indigenous territories and unprotected portions of the landscape. Capture rates through time suggested that lowland tapir populations are recovering within the Tuichi Valley, an area currently dedicated towards ecotourism activities, following the creation (1995) and subsequent implementation (1997) of the Madidi National Park in Bolivia. Based on our distributional data and published conservative estimates of population density, we calculated that this transboundary landscape holds an overall lowland tapir population of between 14 540 and 36 351 individuals, of which at least 24.3% are under protection from national and municipal parks. As such, the Greater Madidi-Tambopata Landscape should be considered a lowland tapir population stronghold and priority conservation efforts are discussed in order to maintain this population. PMID:23253372

  1. Activity characteristics and movement patterns in people with and people without low back pain who participate in rotation-related sports

    PubMed Central

    Chimenti, Ruth L.; Scholtes, Sara A.

    2013-01-01

    Many risk factors have been identified as contributing to the development or persistence of low back pain (LBP). However, the juxtaposition of both high and low levels of physical activity being associated with LBP reflects the complexity of the relationship between a risk factor and LBP. Moreover, not everyone with an identified risk factor, such as a movement pattern of increased lumbopelvic rotation, has LBP. Objective The purpose of this study was to examine differences in activity level and movement patterns between people with and people without chronic or recurrent LBP who participate in rotation-related sports. Design Case Case-control study. Setting University laboratory environment. Participants 52 people with chronic or recurrent LBP and 25 people without LBP who all play a rotation-related sport. Main Outcome Measures Participants completed self-report measures including the Baecke Habitual Activity Questionnaire and a questionnaire on rotation-related sports. A 3-dimensional motion-capture system was used to collect movement-pattern variables during 2 lower-limb-movement tests. Results Compared with people without LBP, people with LBP reported a greater difference between the sport subscore and an average work and leisure composite subscore on the Baecke Habitual Activity Questionnaire (F = 6.55, P = .01). There were no differences between groups in either rotation-related-sport participation or movement-pattern variables demonstrated during 2 lower-limb movement tests (P > .05 for all comparisons). Conclusions People with and people without LBP who regularly play a rotation-related sport differed in the amount and nature of activity participation but not in movement pattern variables. An imbalance between level of activity during sport and daily functions may contribute to the development or persistence of LBP in people who play a rotation-related sport. PMID:23295458

  2. Patterns of Literacy and Numeracy Activities in Preschool and Their Relation to Structural Characteristics and Children's Home Activities

    ERIC Educational Resources Information Center

    Lehrl, Simone; Smidt, Wilfried; Grosse, Christiane; Richter, David

    2014-01-01

    Early literacy and numeracy activities in family and preschool are considered important for promoting children's early literacy and numeracy skills. However, little research exists, especially in Germany, on the frequency of such activities in different contexts. The current study identified patterns of literacy and numeracy activities in…

  3. Patterns of Occurrence and Marine Mammal Acoustic Behavior in Relation to Navy Sonar Activity Off Jacksonville, Florida.

    PubMed

    Oswald, Julie N; Norris, Thomas F; Yack, Tina M; Ferguson, Elizabeth L; Kumar, Anurag; Nissen, Jene; Bell, Joel

    2016-01-01

    Passive acoustic data collected from marine autonomous recording units deployed off Jacksonville, FL (from 13 September to 8 October 2009 and 3 December 2009 to 8 January 2010), were analyzed for detection of cetaceans and Navy sonar. Cetaceans detected included Balaenoptera acutorostrata, Eubalaena glacialis, B. borealis, Physeter macrocephalus, blackfish, and delphinids. E. glacialis were detected at shallow and, somewhat unexpectedly, deep sites. P. macrocephalus were characterized by a strong diel pattern. B. acutorostrata showed the strongest relationship between sonar activity and vocal behavior. These results provide a preliminary assessment of cetacean occurrence off Jacksonville and new insights on vocal responses to sonar. PMID:26611034

  4. PM ACTIVITY PATTERN RESEARCH

    EPA Science Inventory

    Human activity/uptake rate data are necessary to estimate potential human exposure and intake dose to environmental pollutants and to refine human exposure models. Personal exposure monitoring studies have demonstrated the critical role that activities play in explaining and pre...

  5. HUMAN EXPOSURE ACTIVITY PATTERNS

    EPA Science Inventory

    Human activity/uptake rate data are necessary to estimate potential human exposure and intake dose to environmental pollutants and to refine human exposure models. Personal exposure monitoring studies have demonstrated the critical role that activities play in explaining and pre...

  6. Age-Related Changes in BOLD Activation Pattern in Phonemic Fluency Paradigm: An Investigation of Activation, Functional Connectivity and Psychophysiological Interactions.

    PubMed

    La, Christian; Garcia-Ramos, Camille; Nair, Veena A; Meier, Timothy B; Farrar-Edwards, Dorothy; Birn, Rasmus; Meyerand, Mary E; Prabhakaran, Vivek

    2016-01-01

    Healthy aging is associated with decline of cognitive functions. However, even before those declines become noticeable, the neural architecture underlying those mechanisms has undergone considerable restructuring and reorganization. During performance of a cognitive task, not only have the task-relevant networks demonstrated reorganization with aging, which occurs primarily by recruitment of additional areas to preserve performance, but the task-irrelevant network of the "default-mode" network (DMN), which is normally deactivated during task performance, has also consistently shown reduction of this deactivation with aging. Here, we revisited those age-related changes in task-relevant (i.e., language system) and task-irrelevant (i.e., DMN) systems with a language production paradigm in terms of task-induced activation/deactivation, functional connectivity, and context-dependent correlations between the two systems. Our task fMRI data demonstrated a late increase in cortical recruitment in terms of extent of activation, only observable in our older healthy adult group, when compared to the younger healthy adult group, with recruitment of the contralateral hemisphere, but also other regions from the network previously underutilized. Our middle-aged individuals, when compared to the younger healthy adult group, presented lower levels of activation intensity and connectivity strength, with no recruitment of additional regions, possibly reflecting an initial, uncompensated, network decline. In contrast, the DMN presented a gradual decrease in deactivation intensity and deactivation extent (i.e., low in the middle-aged, and lower in the old) and similar gradual reduction of functional connectivity within the network, with no compensation. The patterns of age-related changes in the task-relevant system and DMN are incongruent with the previously suggested notion of anti-correlation of the two systems. The context-dependent correlation by psycho-physiological interaction

  7. Age-Related Changes in BOLD Activation Pattern in Phonemic Fluency Paradigm: An Investigation of Activation, Functional Connectivity and Psychophysiological Interactions

    PubMed Central

    La, Christian; Garcia-Ramos, Camille; Nair, Veena A.; Meier, Timothy B.; Farrar-Edwards, Dorothy; Birn, Rasmus; Meyerand, Mary E.; Prabhakaran, Vivek

    2016-01-01

    Healthy aging is associated with decline of cognitive functions. However, even before those declines become noticeable, the neural architecture underlying those mechanisms has undergone considerable restructuring and reorganization. During performance of a cognitive task, not only have the task-relevant networks demonstrated reorganization with aging, which occurs primarily by recruitment of additional areas to preserve performance, but the task-irrelevant network of the “default-mode” network (DMN), which is normally deactivated during task performance, has also consistently shown reduction of this deactivation with aging. Here, we revisited those age-related changes in task-relevant (i.e., language system) and task-irrelevant (i.e., DMN) systems with a language production paradigm in terms of task-induced activation/deactivation, functional connectivity, and context-dependent correlations between the two systems. Our task fMRI data demonstrated a late increase in cortical recruitment in terms of extent of activation, only observable in our older healthy adult group, when compared to the younger healthy adult group, with recruitment of the contralateral hemisphere, but also other regions from the network previously underutilized. Our middle-aged individuals, when compared to the younger healthy adult group, presented lower levels of activation intensity and connectivity strength, with no recruitment of additional regions, possibly reflecting an initial, uncompensated, network decline. In contrast, the DMN presented a gradual decrease in deactivation intensity and deactivation extent (i.e., low in the middle-aged, and lower in the old) and similar gradual reduction of functional connectivity within the network, with no compensation. The patterns of age-related changes in the task-relevant system and DMN are incongruent with the previously suggested notion of anti-correlation of the two systems. The context-dependent correlation by psycho

  8. Event-related Potential Patterns Reflect Reversed Hemispheric Activity during Visual Attention Processing in Children with Dyslexia: A Preliminary Study

    PubMed Central

    Kang, Joong-Gu; Lee, Seung-Hwan; Park, Eun-Jin; Leem, Hyun-Sung

    2016-01-01

    Objective Individuals with dyslexia experience reading difficulties, whereas their other cognitive abilities seem normal. The purpose of this study was to investigate the event-related potential (ERP) patterns of children with dyslexia during a target-detection task. Methods Seventeen children with dyslexia and 18 children without this disorder participated in this study. We evaluated their writing and reading ability, symptoms of attention-deficit/hyperactivity disorder, and intelligence quotient. ERPs were recorded while participants performed a target-detection task, and the peak amplitude and latency of P100 and P300 were analyzed. The lateral asymmetry index (LAI) was calculated for each ERP component. Results The dyslexic group exhibited longer reaction times and larger P100 amplitudes than the non-dyslexic group in the right hemisphere. The P100 latency was also significantly delayed in the right hemisphere of those in the dyslexic group compared with those in the non-dyslexic group. The P300 amplitude was larger in the right hemisphere compared with left hemisphere in the dyslexic group, whereas no interhemispheric differences were observed with respect to the P300 latency. The LAI for P100 showed a significant right hemispheric dominance, whereas the LAI for P100 was significantly correlated with the accuracy of target detection in children with dyslexia. Conclusion Our results suggest that right hemispheric dominance acts as an ancillary system that compensates for poor reading in children with dyslexia. PMID:26792038

  9. Pattern activation/recognition theory of mind

    PubMed Central

    du Castel, Bertrand

    2015-01-01

    In his 2012 book How to Create a Mind, Ray Kurzweil defines a “Pattern Recognition Theory of Mind” that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call “Pattern Activation/Recognition Theory of Mind.” While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation. PMID:26236228

  10. Pattern activation/recognition theory of mind.

    PubMed

    du Castel, Bertrand

    2015-01-01

    In his 2012 book How to Create a Mind, Ray Kurzweil defines a "Pattern Recognition Theory of Mind" that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call "Pattern Activation/Recognition Theory of Mind." While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation. PMID:26236228

  11. Health-Related Fitness Knowledge and Its Relation to Student Physical Activity Patterns at a Large U.S. Southern State University

    ERIC Educational Resources Information Center

    Keating, Xiaofen D.; Castro-Pinero, Jose; Centeio, Erin; Harrison, Louis, Jr.; Ramirez, Tere; Chen, Li

    2010-01-01

    This study examined student health-related fitness (HRF) knowledge and its relationship to physical activity (PA). The participants were undergraduate students from a large U.S. state university. HRF knowledge was assessed using a test consisting of 150 multiple choice items. Differences in HRF knowledge scores by sex, ethnicity, and years in…

  12. The relative importance of respiratory water loss in scorpions is correlated with species habitat type and activity pattern.

    PubMed

    Gefen, Eran

    2011-01-01

    Scorpions exhibit some of the lowest recorded water loss rates compared with those of other terrestrial arthropods of similar body size. Evaporative water loss (EWL) includes cuticular transpiration and respiratory water loss (RWL) from gas exchange surfaces, that is, book lung lamellae. Estimated fractions of cuticular and respiratory losses currently available from the literature show considerable variation, at least partly as a result of differences in methodology. This study reports RWL rates and their relative importance in scorpions from two families (Buthidae and Scorpionidae), including both xeric and mesic species (or subspecies). Two of the included Buthidae were surface-dwelling species, and another inhabits empty burrows of other terrestrial arthropods. This experimental design enabled correlating RWL importance with scorpion phylogeny, habitat type, and/or homing behavior. Buthidae species exhibited significantly lower EWL rates compared with those of Scorpionidae, whereas effects of habitat type and homing behavior were not significant. Resting RWL rates were not significantly affected by scorpion phylogeny, but rates for the xeric species (totaling ~10% of EWL rates at 30°C) were significantly lower compared with those of mesic species. These lower RWL values were correlated with significantly lower H(2)O/CO(2) emission rates in xeric species. The experimental setup and ~24-h duration of each individual recording allowed estimating the effect of interspecific variation in activity on RWL proportions. The high respiratory losses in active hydrated Scorpio maurus fuscus, totaling 30% of EWL, suggest that behavioral discretion in this species is a more likely mechanism for body water conservation under stressful conditions when compared with the responses of other studied species. PMID:21133796

  13. Persistent Differences in Patterns of Brain Activation after Sports-Related Concussion: A Longitudinal Functional Magnetic Resonance Imaging Study

    PubMed Central

    Murugavel, Murali; Putukian, Margot; Cubon, Valerie; Furtado, John; Osherson, Daniel

    2014-01-01

    Abstract Avoiding recurrent injury in sports-related concussion (SRC) requires understanding the neural mechanisms involved during the time of recovery after injury. The decision for return-to-play is one of the most difficult responsibilities facing the physician, and so far this decision has been based primarily on neurological examination, symptom checklists, and neuropsychological (NP) testing. Functional magnetic resonance imaging (fMRI) may be an additional, more objective tool to assess the severity and recovery of function after concussion. The purpose of this study was to define neural correlates of SRC during the 2 months after injury in varsity contact sport athletes who suffered a SRC. All athletes were scanned as they performed an n-back task, for n=1, 2, 3. Subjects were scanned within 72 hours (session one), at 2 weeks (session two), and 2 months (session three) post-injury. Compared with age and sex matched normal controls, concussed subjects demonstrated persistent, significantly increased activation for the 2 minus 1 n-back contrast in bilateral dorsolateral prefrontal cortex (DLPFC) in all three sessions and in the inferior parietal lobe in session one and two (α≤0.01 corrected). Measures of task performance revealed no significant differences between concussed versus control groups at any of the three time points with respect to any of the three n-back tasks. These findings suggest that functional brain activation differences persist at 2 months after injury in concussed athletes, despite the fact that their performance on a standard working memory task is comparable to normal controls and normalization of clinical and NP test results. These results might indicate a delay between neural and behaviorally assessed recovery after SRC. PMID:23914845

  14. Persistent differences in patterns of brain activation after sports-related concussion: a longitudinal functional magnetic resonance imaging study.

    PubMed

    Dettwiler, Annegret; Murugavel, Murali; Putukian, Margot; Cubon, Valerie; Furtado, John; Osherson, Daniel

    2014-01-15

    Avoiding recurrent injury in sports-related concussion (SRC) requires understanding the neural mechanisms involved during the time of recovery after injury. The decision for return-to-play is one of the most difficult responsibilities facing the physician, and so far this decision has been based primarily on neurological examination, symptom checklists, and neuropsychological (NP) testing. Functional magnetic resonance imaging (fMRI) may be an additional, more objective tool to assess the severity and recovery of function after concussion. The purpose of this study was to define neural correlates of SRC during the 2 months after injury in varsity contact sport athletes who suffered a SRC. All athletes were scanned as they performed an n-back task, for n=1, 2, 3. Subjects were scanned within 72 hours (session one), at 2 weeks (session two), and 2 months (session three) post-injury. Compared with age and sex matched normal controls, concussed subjects demonstrated persistent, significantly increased activation for the 2 minus 1 n-back contrast in bilateral dorsolateral prefrontal cortex (DLPFC) in all three sessions and in the inferior parietal lobe in session one and two (α≤0.01 corrected). Measures of task performance revealed no significant differences between concussed versus control groups at any of the three time points with respect to any of the three n-back tasks. These findings suggest that functional brain activation differences persist at 2 months after injury in concussed athletes, despite the fact that their performance on a standard working memory task is comparable to normal controls and normalization of clinical and NP test results. These results might indicate a delay between neural and behaviorally assessed recovery after SRC. PMID:23914845

  15. fMRI-activation patterns in the detection of concealed information rely on memory-related effects.

    PubMed

    Gamer, Matthias; Klimecki, Olga; Bauermann, Thomas; Stoeter, Peter; Vossel, Gerhard

    2012-06-01

    Recent research on potential applications of fMRI in the detection of concealed knowledge primarily ascribed the reported differences in hemodynamic response patterns to deception. This interpretation is challenged by the results of the present study. Participants were required to memorize probe and target items (a banknote and a playing card, each). Subsequently, these items were repeatedly presented along with eight irrelevant items in a modified Guilty Knowledge Test design and participants were instructed to simply acknowledge item presentation by pressing one button after each stimulus. Despite the absence of response monitoring demands and thus overt response conflicts, the experiment revealed a differential physiological response pattern as a function of item type. First, probes elicited the largest skin conductance responses. Second, differential hemodynamic responses were observed in bilateral inferior frontal regions, the right supramarginal gyrus and the supplementary motor area as a function of item type. Probes and targets were accompanied by a larger signal increase than irrelevant items in these regions. Moreover, the responses to probes differed substantially from targets. The observed neural response pattern seems to rely on retrieval processes that depend on the depth of processing in the encoding situation. PMID:19258375

  16. Physical Activity Patterns during Pregnancy

    PubMed Central

    Borodulin, Katja; Evenson, Kelly R; Wen, Fang; Herring, Amy H.; Benson, Aimee

    2012-01-01

    Purpose The aim of the study was to describe the mode, frequency, duration, and intensity of physical activity among pregnant women, to explore whether these women reached the recommended levels of activity, and to explore how these patterns changed during pregnancy. Methods This study, as part of the third phase of the Pregnancy, Infection, and Nutrition Study, investigated physical activity among 1482 pregnant women. A recall of the different modes, frequency, duration, and intensity of physical activity during the past week was assessed in two telephone interviews at 17–22 and 27–30 weeks’ gestation. Results Most women reported some type of physical activity during both time periods. Child and adult care giving, indoor household, and recreational activities constituted the largest proportion of total reported activity. The overall physical activity level decreased during pregnancy, particularly in care giving, outdoor household, and recreational activity. Women who were active during the second and third trimesters reported higher levels of activity in all modes of activity than those who became active or inactive during pregnancy. The majority did not reach the recommended level of physical activity. Conclusion These data suggest that self-reported physical activity decreased from the second to third trimester and only a small proportion reached the recommended level of activity during pregnancy. Further research is needed to explore if physical activity rebounds during the postpartum period. PMID:18845974

  17. Pattern of stylet penetration activity by Homalodisca vitripennis (Hemiptera: Cicadellidae) adults in relation to environmental temperature and light conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effects of ambient spring air temperature and light intensity on stylet penetration activities of the glassy-winged sharpshooter, Homalodisca vitripennis (Germar) were studied outdoors, at ambient light and temperatures, using an electrical penetration graph (EPG). EPG waveforms representing saliva...

  18. Relational Control Patterns in Families of Schizophrenics.

    ERIC Educational Resources Information Center

    McCarrick, Anne; And Others

    1988-01-01

    Examined patterning of relational control in families of schizophrenic patients, and relationship between control in the family and the course of the illness. Transcripts of conversations among 17 schizophrenic outpatients and their families were coded into Relational Control Coding System. Found rigid, one-up messages from family members to…

  19. [Diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest in the Isthmus of Tehuantepec, Oaxaca, Mexico].

    PubMed

    Cortés-Marcial, Malinalli; Briones-Salas, Miguel

    2014-12-01

    The use of camera traps and mammal track search are complementary methods to monitoring species of which is not well documented their natural history, as in the case of medium and large mammals. To ensure its conservation and good management, it is necessary to generate information about the structure of the community and their populations. The objective of the present study was to estimate the diversity, relative abundance and activity patterns of medium and large mammals in a tropical deciduous forest located in the Isthmus of Tehuantepec, Oaxaca, Mexico. Samplings were conducted in three month intervals, from September 2011 to May 2013. We used photographic-sampling and track search, two complementary sampling methods. For photographic-sampling, 12 camera traps were placed covering an area of 60 km2, while for the tracks search a monthly tour of four line-transect surveys of three kilometers length each was undertaken. We obtained a total of 344 pictures with 5292 trap-days total sampling effort; in addition, 187 track records in a total of 144 km. With both methods we registered 21 species of mammals, in 13 families and seven orders, and five species resulted in new records to the area. The diversity index of Shannon-Wiener obtained with the method of tracks was H' = 2.41, while the most abundant species were Urocyon cinereoargen- teus (IAR = 0.23) and Pecari tajacu (IAR = 0.20). By the method of trap the most abundant species were P. tajacu (IAR = 2.62) and Nasua narica (IAR = 1.28). In terms of patterns of activity P. tajacu, N. narica and Odocoileus virginianus were primarily diurnal species; Canis latrans and Leopardus pardalis did not show preference for any schedule in particular, and Didelphis virginiana and Dasypus novemcinctus preferred to have nocturnal activity. This information can be of help to the creation of programs of management and conservation of mam- mals of medium and large in the Isthmus of Tehuantepec, Oaxaca, México. PMID:25720178

  20. Parent-Reported Eating and Leisure-Time Activity Selection Patterns Related to Energy Balance in Preschool- and School-Aged Children

    ERIC Educational Resources Information Center

    Raynor, Hollie A.; Jelalian, Elissa; Vivier, Patrick M.; Hart, Chantelle N.; Wing, Rena R.

    2009-01-01

    Objective: Compare parent-reported preschool- and school-aged children's eating and leisure-time activity patterns that are proposed to influence energy balance. Design: Cross-sectional investigation of children, 2 to 12 years, attending a well visit. Setting: Pediatric private practice/ambulatory pediatric clinic. Participants: One hundred…

  1. Patterns in Safety-Related Projects

    NASA Astrophysics Data System (ADS)

    Parsons, Mike; Hunter, Charles

    Within Logica UK, safety-related projects are run in a variety of ways depending on the constraints imposed and how the risks and mitigations are owned and handled. A total of eight different types of project development patterns have been identified and this paper discusses each type. A simple decision tool has been developed based on the patterns which is used as an aid in deciding how to bid a safety project, allowing tradeoffs between risk ownership, development methods and cost to be assessed.

  2. Pattern classification using fuzzy relational calculus.

    PubMed

    Ray, K S; Dinda, T K

    2003-01-01

    Our aim is to design a pattern classifier using fuzzy relational calculus (FRC) which was initially proposed by Pedrycz (1990). In the course of doing so, we first consider a particular interpretation of the multidimensional fuzzy implication (MFI) to represent our knowledge about the training data set. Subsequently, we introduce the notion of a fuzzy pattern vector to represent a population of training patterns in the pattern space and to denote the antecedent part of the said particular interpretation of the MFI. We introduce a new approach to the computation of the derivative of the fuzzy max-function and min-function using the concept of a generalized function. During the construction of the classifier based on FRC, we use fuzzy linguistic statements (or fuzzy membership function to represent the linguistic statement) to represent the values of features (e.g., feature F/sub 1/ is small and F/sub 2/ is big) for a population of patterns. Note that the construction of the classifier essentially depends on the estimate of a fuzzy relation /spl Rfr/ between the input (fuzzy set) and output (fuzzy set) of the classifier. Once the classifier is constructed, the nonfuzzy features of a pattern can be classified. At the time of classification of the nonfuzzy features of the testpatterns, we use the concept of fuzzy masking to fuzzify the nonfuzzy feature values of the testpatterns. The performance of the proposed scheme is tested on synthetic data. Finally, we use the proposed scheme for the vowel classification problem of an Indian language. PMID:18238152

  3. Visual Templates in Pattern Generalization Activity

    ERIC Educational Resources Information Center

    Rivera, F. D.

    2010-01-01

    In this research article, I present evidence of the existence of visual templates in pattern generalization activity. Such templates initially emerged from a 3-week design-driven classroom teaching experiment on pattern generalization involving linear figural patterns and were assessed for existence in a clinical interview that was conducted four…

  4. Asteroseismic stellar activity relations

    NASA Astrophysics Data System (ADS)

    Bonanno, A.; Corsaro, E.; Karoff, C.

    2014-11-01

    Context. In asteroseismology an important diagnostic of the evolutionary status of a star is the small frequency separation which is sensitive to the gradient of the mean molecular weight in the stellar interior. It is thus interesting to discuss the classical age-activity relations in terms of this quantity. Moreover, as the photospheric magnetic field tends to suppress the amplitudes of acoustic oscillations, it is important to quantify the importance of this effect by considering various activity indicators. Aims: We propose a new class of age-activity relations that connects the Mt. Wilson S index and the average scatter in the light curve with the small frequency separation and the amplitude of the p-mode oscillations. Methods: We used a Bayesian inference to compute the posterior probability of various empirical laws for a sample of 19 solar-like active stars observed by the Kepler telescope. Results: We demonstrate the presence of a clear correlation between the Mt. Wilson S index and the relative age of the stars as indicated by the small frequency separation, as well as an anti-correlation between the S index and the oscillation amplitudes. We argue that the average activity level of the stars shows a stronger correlation with the small frequency separation than with the absolute age that is often considered in the literature. Conclusions: The phenomenological laws discovered in this paper have the potential to become new important diagnostics to link stellar evolution theory with the dynamics of global magnetic fields. In particular we argue that the relation between the Mt. Wilson S index and the oscillation amplitudes is in good agreement with the findings of direct numerical simulations of magneto-convection.

  5. Parent-reported eating and leisure-time activity selection patterns related to energy balance in preschool-and school-aged children

    PubMed Central

    Raynor, Hollie A.; Jelalian, Elissa; Vivier, Patrick M.; Hart, Chantelle N.; Wing, Rena R.

    2009-01-01

    Objective Compare parent-reported preschool- and school-aged children’s eating and leisure-time activity patterns that are proposed to influence energy balance. Design Cross-sectional investigation of children, 2 to 12 years, attending a well-visit. Setting Pediatric private practice/ambulatory pediatric clinic. Participants One hundred seventy-four children: 49% preschool-aged, 54% female, 28% Hispanic, and 34% overweight/at risk for overweight. Variables Measured Parent-reported eating/leisure-time behaviors. Height/weight from medical records. Analysis Analyses of covariance/Chi-square tests; significance at P ≤ 0.05. Results By parents’ report, preschool-aged children consumed more servings/day of low-fat dairy (2.1 ± 1.6 vs. 1.7 ± 1.5; P <.01), fewer servings/day of sweetened drinks (1.4 ± 1.9 vs. 2.2 ± 2.6; P <.01), and watched fewer hours/day of weekend TV (2.3 ± 1. 3 vs. 2.7 ± 1.3; P <.05) than school-aged children. Fewer preschool-aged children consumed salty (14.0% vs. 26.1%; P <.05) and sweet (16.3% vs. 29.5%; P <.05) snack foods daily, and a greater percentage regularly consumed dinner with a parent (93.0% vs. 80.7%; P <.05), as assessed by parent report. Conclusions and Implications Parent-reported children’s eating/leisure-time patterns that may influence energy balance were less healthy in the school-aged children. However, most children did not meet recommendations, irrespective of age/weight. Interventions for meeting recommendations should start with families with preschool-aged children. Future research should focus on identifying factors that might be contributing to increased reporting of problematic food and leisure-time activity patterns in school-aged children. PMID:19161916

  6. New activity pattern in human interactive dynamics

    NASA Astrophysics Data System (ADS)

    Formentin, Marco; Lovison, Alberto; Maritan, Amos; Zanzotto, Giovanni

    2015-09-01

    We investigate the response function of human agents as demonstrated by written correspondence, uncovering a new pattern for how the reactive dynamics of individuals is distributed across the set of each agent’s contacts. In long-term empirical data on email, we find that the set of response times considered separately for the messages to each different correspondent of a given writer, generate a family of heavy-tailed distributions, which have largely the same features for all agents, and whose characteristic times grow exponentially with the rank of each correspondent. We furthermore show that this new behavioral pattern emerges robustly by considering weighted moving averages of the priority-conditioned response-time probabilities generated by a basic prioritization model. Our findings clarify how the range of priorities in the inputs from one’s environment underpin and shape the dynamics of agents embedded in a net of reactive relations. These newly revealed activity patterns might be universal, being present in other general interactive environments, and constrain future models of communication and interaction networks, affecting their architecture and evolution.

  7. Microgravity effects on 'postural' muscle activity patterns

    NASA Technical Reports Server (NTRS)

    Layne, Charles S.; Spooner, Brian S.

    1994-01-01

    Changes in neuromuscular activation patterns associated with movements made in microgravity can contribute to muscular atrophy. Using electromyography (EMG) to monitor 'postural' muscles, it was found that free floating arm flexions made in microgravity were not always preceded by neuromuscular activation patterns normally observed during movements made in unit gravity. Additionally, manipulation of foot sensory input during microgravity arm flexion impacted upon anticipatory postural muscle activation.

  8. Immediate and prolonged patterns of Agouti-related peptide-(83--132)-induced c-Fos activation in hypothalamic and extrahypothalamic sites.

    PubMed

    Hagan, M M; Benoit, S C; Rushing, P A; Pritchard, L M; Woods, S C; Seeley, R J

    2001-03-01

    Several lines of evidence substantiate the important role of the central nervous system melanocortin 3- and 4-receptor (MC3/4-R) system in the control of food intake and energy balance. Agouti-related peptide (AgRP), an endogenous antagonist of these receptors, produces a robust and unique pattern of increased food intake that lasts up to 7 days after a single injection. Little is known about brain regions that may mediate this powerful effect of AgRP on food intake. To this end we compared c-Fos-like immunoreactivity (c-FLI) in several brain sites of rats injected intracerebroventricularly with 1 nmol AgRP-(83--132) 2 and 24 h before death and compared c-FLI patterns to those induced by another potent orexigenic peptide, neuropeptide Y (NPY). Although both NPY and AgRP induced c-FLI in hypothalamic areas, AgRP also produced increased c-FLI in the accumbens shell and lateral septum. Although NPY elicited no changes in c-FLI 24 h after administration, AgRP induced c-FLI in the accumbens shell, nucleus of the solitary tract, central amygdala, and lateral hypothalamus. These results indicate that an NPY-like hypothalamic circuit mediates the short-term effects of AgRP, but that the unique sustained effect of AgRP on food intake involves a complex circuit of key extrahypothalamic reward and feeding regulatory nuclei. PMID:11181518

  9. Posterior Cingulate Cortex-Related Co-Activation Patterns: A Resting State fMRI Study in Propofol-Induced Loss of Consciousness

    PubMed Central

    Amico, Enrico; Gomez, Francisco; Di Perri, Carol; Vanhaudenhuyse, Audrey; Lesenfants, Damien; Boveroux, Pierre; Bonhomme, Vincent; Brichant, Jean-François; Marinazzo, Daniele; Laureys, Steven

    2014-01-01

    Background Recent studies have been shown that functional connectivity of cerebral areas is not a static phenomenon, but exhibits spontaneous fluctuations over time. There is evidence that fluctuating connectivity is an intrinsic phenomenon of brain dynamics that persists during anesthesia. Lately, point process analysis applied on functional data has revealed that much of the information regarding brain connectivity is contained in a fraction of critical time points of a resting state dataset. In the present study we want to extend this methodology for the investigation of resting state fMRI spatial pattern changes during propofol-induced modulation of consciousness, with the aim of extracting new insights on brain networks consciousness-dependent fluctuations. Methods Resting-state fMRI volumes on 18 healthy subjects were acquired in four clinical states during propofol injection: wakefulness, sedation, unconsciousness, and recovery. The dataset was reduced to a spatio-temporal point process by selecting time points in the Posterior Cingulate Cortex (PCC) at which the signal is higher than a given threshold (i.e., BOLD intensity above 1 standard deviation). Spatial clustering on the PCC time frames extracted was then performed (number of clusters = 8), to obtain 8 different PCC co-activation patterns (CAPs) for each level of consciousness. Results The current analysis shows that the core of the PCC-CAPs throughout consciousness modulation seems to be preserved. Nonetheless, this methodology enables to differentiate region-specific propofol-induced reductions in PCC-CAPs, some of them already present in the functional connectivity literature (e.g., disconnections of the prefrontal cortex, thalamus, auditory cortex), some others new (e.g., reduced co-activation in motor cortex and visual area). Conclusion In conclusion, our results indicate that the employed methodology can help in improving and refining the characterization of local functional changes in the

  10. Pattern Formation on Networks: from Localised Activity to Turing Patterns

    PubMed Central

    McCullen, Nick; Wagenknecht, Thomas

    2016-01-01

    Networks of interactions between competing species are used to model many complex systems, such as in genetics, evolutionary biology or sociology and knowledge of the patterns of activity they can exhibit is important for understanding their behaviour. The emergence of patterns on complex networks with reaction-diffusion dynamics is studied here, where node dynamics interact via diffusion via the network edges. Through the application of a generalisation of dynamical systems analysis this work reveals a fundamental connection between small-scale modes of activity on networks and localised pattern formation seen throughout science, such as solitons, breathers and localised buckling. The connection between solutions with a single and small numbers of activated nodes and the fully developed system-scale patterns are investigated computationally using numerical continuation methods. These techniques are also used to help reveal a much larger portion of of the full number of solutions that exist in the system at different parameter values. The importance of network structure is also highlighted, with a key role being played by nodes with a certain so-called optimal degree, on which the interaction between the reaction kinetics and the network structure organise the behaviour of the system. PMID:27273339

  11. Pattern Formation on Networks: from Localised Activity to Turing Patterns

    NASA Astrophysics Data System (ADS)

    McCullen, Nick; Wagenknecht, Thomas

    2016-06-01

    Networks of interactions between competing species are used to model many complex systems, such as in genetics, evolutionary biology or sociology and knowledge of the patterns of activity they can exhibit is important for understanding their behaviour. The emergence of patterns on complex networks with reaction-diffusion dynamics is studied here, where node dynamics interact via diffusion via the network edges. Through the application of a generalisation of dynamical systems analysis this work reveals a fundamental connection between small-scale modes of activity on networks and localised pattern formation seen throughout science, such as solitons, breathers and localised buckling. The connection between solutions with a single and small numbers of activated nodes and the fully developed system-scale patterns are investigated computationally using numerical continuation methods. These techniques are also used to help reveal a much larger portion of of the full number of solutions that exist in the system at different parameter values. The importance of network structure is also highlighted, with a key role being played by nodes with a certain so-called optimal degree, on which the interaction between the reaction kinetics and the network structure organise the behaviour of the system.

  12. Pattern Formation on Networks: from Localised Activity to Turing Patterns.

    PubMed

    McCullen, Nick; Wagenknecht, Thomas

    2016-01-01

    Networks of interactions between competing species are used to model many complex systems, such as in genetics, evolutionary biology or sociology and knowledge of the patterns of activity they can exhibit is important for understanding their behaviour. The emergence of patterns on complex networks with reaction-diffusion dynamics is studied here, where node dynamics interact via diffusion via the network edges. Through the application of a generalisation of dynamical systems analysis this work reveals a fundamental connection between small-scale modes of activity on networks and localised pattern formation seen throughout science, such as solitons, breathers and localised buckling. The connection between solutions with a single and small numbers of activated nodes and the fully developed system-scale patterns are investigated computationally using numerical continuation methods. These techniques are also used to help reveal a much larger portion of of the full number of solutions that exist in the system at different parameter values. The importance of network structure is also highlighted, with a key role being played by nodes with a certain so-called optimal degree, on which the interaction between the reaction kinetics and the network structure organise the behaviour of the system. PMID:27273339

  13. Generating Coherent Patterns of Activity from Chaotic Neural Networks

    PubMed Central

    Sussillo, David; Abbott, L. F.

    2009-01-01

    Neural circuits display complex activity patterns both spontaneously and when responding to a stimulus or generating a motor output. How are these two forms of activity related? We develop a procedure called FORCE learning for modifying synaptic strengths either external to or within a model neural network to change chaotic spontaneous activity into a wide variety of desired activity patterns. FORCE learning works even though the networks we train are spontaneously chaotic and we leave feedback loops intact and unclamped during learning. Using this approach, we construct networks that produce a wide variety of complex output patterns, input-output transformations that require memory, multiple outputs that can be switched by control inputs, and motor patterns matching human motion capture data. Our results reproduce data on pre-movement activity in motor and premotor cortex, and suggest that synaptic plasticity may be a more rapid and powerful modulator of network activity than generally appreciated. PMID:19709635

  14. Pattern of phenolic content, antioxidant activity and senescence-related enzymes in granulated vs non-granulated juice-sacs of 'Kinnow' mandarin (Citrus nobilis x C. deliciosa).

    PubMed

    Sharma, R R; Awasthi, O P; Kumar, Kuldeep

    2016-03-01

    'Kinnow' is a hybrid mandarin, developed at California (USA) but could not become successful there. However, it revolutionized citrus industry in India, Pakistan and Bangladesh. Recent reports indicate that like other citrus fruits, it also suffers from juice-sac granulation but exact cause of this malady is not known. Fully-mature 'Kinnow' fruits were harvested and observations on some physical and biochemical attributes were recorded and their relationship was established with occurrence of granulation. About 12.8 % 'Kinnow' fruits were affected by juice-sac granulation. Granulated fruits had higher average weight (178 ± 2.26 g), peel thickness (3.72 ± 0.23 mm), and less soluble solids concentrates (7.4 ± 0.21 %) than non-granulated fruits. Granulated fruits exhibited lower concentrations of total phenolics compounds (4.3 ± 0.56 mg 100(-1) g gallic acid equivalent fresh weigh) and antioxidants activity (1.78 ± 0.29 μmol Trolox g(-1) FW) but produced higher rates of carbon dioxide and ethylene, and exhibited higher activities of senescent-related enzymes such as lipoxygenase (LOX) (1.3 ± 0.31 μmoles min(-1) g(-1) FW) and pectin methylesterase (PME) (0.52 ± 0.12 μmol of NaOH g(-1) FW min(-1)) and had strong relationships with the occurrence of granulation. From this study, it can be concluded that total phenolics compounds, antioxidants and PAL enzyme activity have strongly negative co-relation; whereas, senescent-related enzymes such as LOX, and PME and rates of respiration or ethylene evolution have strongly positive relationships with the occurrence of granulation in 'Kinnow' mandarin. PMID:27570277

  15. Young School Children's Recess Physical Activity: Movement Patterns and Preferences

    ERIC Educational Resources Information Center

    Woods, Amelia M.; Graber, Kim C.; Daum, David N.; Gentry, Chris

    2015-01-01

    This study examined physical activity (PA) variables related to recess PA patterns of kindergarten, first and second grade children, and the social preferences and individuals influencing their PA. Data collected (N = 147) used the System of Observing Children's Activity and Relationships during Play (SOCARP) instrument. Children were interviewed.…

  16. Children's Recess Physical Activity: Movement Patterns and Preferences

    ERIC Educational Resources Information Center

    Woods, Amelia Mays; Graber, Kim C.; Daum, David Newman

    2012-01-01

    The benefits of recess can be reaped by all students regardless of socioeconomic status, race, or gender and at relatively little cost. The purpose of this study was to examine physical activity (PA) variables related to the recess PA patterns of third and fourth grade children and the social preferences and individuals influencing their PA…

  17. Motor patterns during active electrosensory acquisition

    PubMed Central

    Hofmann, Volker; Geurten, Bart R. H.; Sanguinetti-Scheck, Juan I.; Gómez-Sena, Leonel; Engelmann, Jacob

    2014-01-01

    Motor patterns displayed during active electrosensory acquisition of information seem to be an essential part of a sensory strategy by which weakly electric fish actively generate and shape sensory flow. These active sensing strategies are expected to adaptively optimize ongoing behavior with respect to either motor efficiency or sensory information gained. The tight link between the motor domain and sensory perception in active electrolocation make weakly electric fish like Gnathonemus petersii an ideal system for studying sensory-motor interactions in the form of active sensing strategies. Analyzing the movements and electric signals of solitary fish during unrestrained exploration of objects in the dark, we here present the first formal quantification of motor patterns used by fish during electrolocation. Based on a cluster analysis of the kinematic values we categorized the basic units of motion. These were then analyzed for their associative grouping to identify and extract short coherent chains of behavior. This enabled the description of sensory behavior on different levels of complexity: from single movements, over short behaviors to more complex behavioral sequences during which the kinematics alter between different behaviors. We present detailed data for three classified patterns and provide evidence that these can be considered as motor components of active sensing strategies. In accordance with the idea of active sensing strategies, we found categorical motor patterns to be modified by the sensory context. In addition these motor patterns were linked with changes in the temporal sampling in form of differing electric organ discharge frequencies and differing spatial distributions. The ability to detect such strategies quantitatively will allow future research to investigate the impact of such behaviors on sensing. PMID:24904337

  18. Automobile Collisions, Kinematics and Related Injury Patterns

    PubMed Central

    Siegel, A. W.

    1972-01-01

    It has been determined clinically that fatalities and injury severity resulting from automobile collisions have decreased during the last five years for low impact speeds. This reduction is a direct result of the application of biomechanics and occupant kinematics, as well as changes in automobile design. The paper defines terminology used in the field of mechanics and develops examples and illustrations of the physical concepts of acceleration, force strength, magnitude duration, rate of onset and others, as they apply to collision phenomena and injury. The mechanism of injury pattern reduction through the use of restraint systems is illustrated. PMID:5059661

  19. Patterns of seismic activity preceding large earthquakes

    NASA Technical Reports Server (NTRS)

    Shaw, Bruce E.; Carlson, J. M.; Langer, J. S.

    1992-01-01

    A mechanical model of seismic faults is employed to investigate the seismic activities that occur prior to major events. The block-and-spring model dynamically generates a statistical distribution of smaller slipping events that precede large events, and the results satisfy the Gutenberg-Richter law. The scaling behavior during a loading cycle suggests small but systematic variations in space and time with maximum activity acceleration near the future epicenter. Activity patterns inferred from data on seismicity in California demonstrate a regional aspect; increased activity in certain areas are found to precede major earthquake events. One example is given regarding the Loma Prieta earthquake of 1989 which is located near a fault section associated with increased activity levels.

  20. Earthquake networks based on similar activity patterns.

    PubMed

    Tenenbaum, Joel N; Havlin, Shlomo; Stanley, H Eugene

    2012-10-01

    Earthquakes are a complex spatiotemporal phenomenon, the underlying mechanism for which is still not fully understood despite decades of research and analysis. We propose and develop a network approach to earthquake events. In this network, a node represents a spatial location while a link between two nodes represents similar activity patterns in the two different locations. The strength of a link is proportional to the strength of the cross correlation in activities of two nodes joined by the link. We apply our network approach to a Japanese earthquake catalog spanning the 14-year period 1985-1998. We find strong links representing large correlations between patterns in locations separated by more than 1000 kilometers, corroborating prior observations that earthquake interactions have no characteristic length scale. We find network characteristics not attributable to chance alone, including a large number of network links, high node assortativity, and strong stability over time. PMID:23214652

  1. Pattern formation in Active Polar Fluids

    NASA Astrophysics Data System (ADS)

    Gopinath, Arvind; Hagan, Michael; Baskaran, Aparna

    2011-03-01

    Systems such as bacterial suspensions or cytoskeletal filaments and motility assays can be described within the paradigm of active polar fluids. These systems have been shown to exhibit pattern formation raging from asters and vortices to traveling stripes. A coarse-grained description of such a fluid is given by a scalar density field and a vector polarization field. We study such a macroscopic description of the system using weakly nonlinear analysis and numerical simulations to map out the emergent pattern formation as a function of the hydrodynamic parameters in the context of two specific microscopic models - a quasi-2D suspension of cytoskeletal filaments and motor proteins and a system of self propelled hard rods that interact through excluded volume interactions. The authors thank the Brandeis MRSEC center for financial support.

  2. Circulation patterns in active lava lakes

    NASA Astrophysics Data System (ADS)

    Redmond, T. C.; Lev, E.

    2014-12-01

    Active lava lakes provide a unique window into magmatic conduit processes. We investigated circulation patterns of 4 active lava lakes: Kilauea's Halemaumau crater, Mount Erebus, Erta Ale and Nyiragongo, and in an artificial "lava lake" constructed at the Syracuse University Lava Lab. We employed visual and thermal video recordings collected at these volcanoes and use computer vision techniques to extract time-dependent, two-dimensional surface velocity maps. The large amount of data available from Halemaumau enabled us to identify several characteristic circulation patterns. One such pattern is a rapid acceleration followed by rapid deceleration, often to a level lower than the pre-acceleration level, and then a slow recovery. Another pattern is periodic asymmetric peaks of gradual acceleration and rapid deceleration, or vice versa, previously explained by gas pistoning. Using spectral analysis, we find that the dominant period of circulation cycles at approximately 30 minutes, 3 times longer than the dominant period identified previously for Mount Erebus. Measuring a complete surface velocity field allowed us to map and follow locations of divergence and convergence, therefore upwelling and downwelling, thus connecting the surface flow with that at depth. At Nyiragongo, the location of main upwelling shifts gradually, yet is usually at the interior of the lake, for Erebus it is usually along the perimeter yet often there is catastrophic downwelling at the interior; For Halemaumau upwelling/downwelling position is almost always on the perimeter. In addition to velocity fields, we developed an automated tool for counting crustal plates at the surface of the lava lakes, and found a correlation, and a lag time, between changes if circulation vigor and the average size of crustal plates. Circulation in the artificial basaltic lava "lake" was limited by its size and degree of foaming, yet we measured surface velocities and identify patterns. Maximum surface velocity

  3. Dynamic patterns of academic forum activities

    NASA Astrophysics Data System (ADS)

    Zhao, Zhi-Dan; Gao, Ya-Chun; Cai, Shi-Min; Zhou, Tao

    2016-11-01

    A mass of traces of human activities show rich dynamic patterns. In this article, we comprehensively investigate the dynamic patterns of 50 thousands of researchers' activities in Sciencenet, the largest multi-disciplinary academic community in China. Through statistical analyses, we found that (i) there exists a power-law scaling between the frequency of visits to an academic forum and the number of corresponding visitors, with the exponent being about 1.33; (ii) the expansion process of academic forums obeys the Heaps' law, namely the number of distinct visited forums to the number of visits grows in a power-law form with exponent being about 0.54; (iii) the probability distributions of time intervals and the number of visits taken to revisit the same academic forum both follow power-laws, indicating the existence of memory effect in academic forum activities. On the basis of these empirical results, we propose a dynamic model that incorporates the exploration, preferential return with memory effect, which can well reproduce the observed scaling laws.

  4. Relating movement recurrence and expressive timing patterns in music performances.

    PubMed

    Teixeira, Euler C F; Yehia, Hani C; Loureiro, Mauricio A

    2015-09-01

    In this study the movement patterns of ten expert musicians are quantitatively related to expressive timing patterns and the music structure during performances. The hypothesis is that ancillary gestures recurrently employed are closely related to expressive intentions, and that the expressive content imposed in key musical passages is thus reflected in the patterns of gestural recurrence. A movement and an audio analysis of 30 clarinet performances of a Brahms' excerpt are compared. Results show direct correlations between the recurrence pattern of clarinetists' ancillary movements and expressive bar duration manipulations employed by them, associated with melodic phrasing and harmonic transitions. PMID:26428815

  5. Implementing Graph Pattern Queries on a Relational Database

    SciTech Connect

    Kaplan, I L; Abdulla, G M; Brugger, S T; Kohn, S R

    2007-12-26

    When a graph database is implemented on top of a relational database, queries in the graph query language are translated into relational SQL queries. Graph pattern queries are an important feature of a graph query language. Translating graph pattern queries into single SQL statements results in very poor query performance. By taking into account the pattern query structure and generating multiple SQL statements, pattern query performance can be dramatically improved. The performance problems encountered with the single SQL statements generated for pattern queries reflects a problem in the SQL query planner and optimizer. Addressing this problem would allow relational databases to better support semantic graph databases. Relational database systems that provide good support for graph databases may also be more flexible platforms for data warehouses.

  6. Patterns of muscle activity for digital coarticulation

    PubMed Central

    Winges, Sara A.; Furuya, Shinichi; Faber, Nathaniel J.

    2013-01-01

    Although piano playing is a highly skilled task, basic features of motor pattern generation may be shared across tasks involving fine movements, such as handling coins, fingering food, or using a touch screen. The scripted and sequential nature of piano playing offered the opportunity to quantify the neuromuscular basis of coarticulation, i.e., the manner in which the muscle activation for one sequential element is altered to facilitate production of the preceding and subsequent elements. Ten pianists were asked to play selected pieces with the right hand at a uniform tempo. Key-press times were recorded along with the electromyographic (EMG) activity from seven channels: thumb flexor and abductor muscles, a flexor for each finger, and the four-finger extensor muscle. For the thumb and index finger, principal components of EMG waveforms revealed highly consistent variations in the shape of the flexor bursts, depending on the type of sequence in which a particular central key press was embedded. For all digits, the duration of the central EMG burst scaled, along with slight variations across subjects in the duration of the interkeystroke intervals. Even within a narrow time frame (about 100 ms) centered on the central EMG burst, the exact balance of EMG amplitudes across multiple muscles depended on the nature of the preceding and subsequent key presses. This fails to support the idea of fixed burst patterns executed in sequential phases and instead provides evidence for neuromuscular coarticulation throughout the time course of a hand movement sequence. PMID:23596338

  7. Complex genetic patterns in closely related colonizing invasive species

    EPA Science Inventory

    Anthropogenic activities frequently result in both rapidly changing environments and translocation of species from their native ranges (i.e., biological invasions). Empirical studies suggest that many factors associated with these changes can lead to complex genetic patterns, par...

  8. Preschooler Sleep Patterns Related to Cognitive and Adaptive Functioning

    ERIC Educational Resources Information Center

    Keefe-Cooperman, Kathleen; Brady-Amoon, Peggy

    2014-01-01

    Research Findings: Preschoolers' sleep patterns were examined related to cognitive and adaptive functioning. The sample consisted of 874 typically developing preschool children with a mean age of 40.01 months. Parent/caregiver reports of children's sleep pattern factors, Stanford-Binet 5 intelligence scale scores, and Behavior Assessment…

  9. Dormitory Architecture Influences. Patterns of Student Social Relations over Time.

    ERIC Educational Resources Information Center

    Case, F. Duncan

    1981-01-01

    Reports findings of a two-part study on the influence of dormitory architecture on patterns of social relations among college undergraduates. The first part investigates how dormitory architecture affects patterns of freshman acquaintance, while the second part studies changes in these relationships over the college years. (Author/WB)

  10. Cortical Activity Patterns in ADHD during Arousal, Activation and Sustained Attention

    ERIC Educational Resources Information Center

    Loo, Sandra K.; Hale, T. Sigi; Macion, James; Hanada, Grant; McGough, James J.; McCracken, James T.; Smalley, Susan L.

    2009-01-01

    Objective: The goal of the present study is to test whether there are Attention-Deficit Hyperactivity Disorder (ADHD)-related differences in brain electrical activity patterns across arousal, activation and vigilance states. Method: The sample consists of 80 adults (38 with ADHD and 42 non-ADHD controls) who were recruited for a family study on…

  11. Marine Biology Activities. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  12. Muscle activity pattern dependent pain development and alleviation.

    PubMed

    Sjøgaard, Gisela; Søgaard, Karen

    2014-12-01

    Muscle activity is for decades considered to provide health benefits irrespectively of the muscle activity pattern performed and whether it is during e.g. sports, transportation, or occupational work tasks. Accordingly, the international recommendations for public health-promoting physical activity do not distinguish between occupational and leisure time physical activity. However, in this body of literature, attention has not been paid to the extensive documentation on occupational physical activity imposing a risk of impairment of health - in particular musculoskeletal health in terms of muscle pain. Focusing on muscle activity patterns and musculoskeletal health it is pertinent to elucidate the more specific aspects regarding exposure profiles and body regional pain. Static sustained muscle contraction for prolonged periods often occurs in the neck/shoulder area during occupational tasks and may underlie muscle pain development in spite of rather low relative muscle load. Causal mechanisms include a stereotype recruitment of low threshold motor units (activating type 1 muscle fibers) characterized by a lack of temporal as well as spatial variation in recruitment. In contrast during physical activities at leisure and sport the motor recruitment patterns are more dynamic including regularly relatively high muscle forces - also activating type 2 muscles fibers - as well as periods of full relaxation even of the type 1 muscle fibers. Such activity is unrelated to muscle pain development if adequate recovery is granted. However, delayed muscle soreness may develop following intensive eccentric muscle activity (e.g. down-hill skiing) with peak pain levels in thigh muscles 1-2 days after the exercise bout and a total recovery within 1 week. This acute pain profile is in contrast to the chronic muscle pain profile related to repetitive monotonous work tasks. The painful muscles show adverse functional, morphological, hormonal, as well as metabolic characteristics. Of

  13. Autogenic training alters cerebral activation patterns in fMRI.

    PubMed

    Schlamann, Marc; Naglatzki, Ryan; de Greiff, Armin; Forsting, Michael; Gizewski, Elke R

    2010-10-01

    Cerebral activation patterns during the first three auto-suggestive phases of autogenic training (AT) were investigated in relation to perceived experiences. Nineteen volunteers trained in AT and 19 controls were studied with fMRI during the first steps of autogenic training. FMRI revealed activation of the left postcentral areas during AT in those with experience in AT, which also correlated with the level of AT experience. Activation of prefrontal and insular cortex was significantly higher in the group with experience in AT while insular activation was correlated with number years of simple relaxation exercises. Specific activation in subjects experienced in AT may represent a training effect. Furthermore, the correlation of insular activation suggests that these subjects are different from untrained subjects in emotional processing or self-awareness. PMID:20799123

  14. Categorizing Pedagogical Patterns by Teaching Activities and Pedagogical Values

    ERIC Educational Resources Information Center

    Bennedsen, Jens; Eriksen, Ole

    2006-01-01

    The main contribution of this paper is a proposal for a universal pedagogical pattern categorization based on teaching values and activities. This categorization would be more sustainable than the arbitrary categorization implied by pedagogical pattern language themes. Pedagogical patterns from two central patterns languages are analyzed and…

  15. Functional Communication Patterns and Relational Concern in Interpersonal Conflict.

    ERIC Educational Resources Information Center

    Spear, Stephen J.; Miller, Larry D.

    A study explored the relationship between the functional communication patterns occurring in conflict and post conflict impressions of relational concern. The first part of the study involved the development and testing of an instrument to measure perceived relational concern, while the second part investigated whether varying styles of functional…

  16. Whales. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Jones, Claire

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  17. Beaches. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Marrett, Andrea

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  18. Waterbirds. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Russell, Barbara

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  19. Tides. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Marrett, Andrea

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  20. Research Note: Patterns of Alcohol-Related Mortality in Russia

    PubMed Central

    Pridemore, William Alex; Kim, Sang-Weon

    2006-01-01

    The level of alcohol consumption in Russia is among the highest in the world and is often associated with a variety of problems in the country. Until recently, however, it was impossible to examine the health and social burdens associated with consumption in Russia due to Soviet secrecy surrounding vital statistics and health data related to alcohol and other topics. This study employed newly available mortality data to describe the demographic, temporal, and spatial patterns of mortality resulting directly from chronic and acute alcohol consumption in the country. The data reveal that in spite of high overall rates of alcohol-related mortality in Russia, levels of mortality vary considerably along these dimensions. Although descriptive in nature, the patterns of alcohol-related mortality in Russia presented here should provide initial observations with which to generate and test hypotheses concerning the causes and consequences of these patterns. PMID:16900263

  1. A central pattern generator producing alternative outputs: temporal pattern of premotor activity.

    PubMed

    Norris, Brian J; Weaver, Adam L; Morris, Lee G; Wenning, Angela; García, Paul A; Calabrese, Ronald L

    2006-07-01

    The central pattern generator for heartbeat in medicinal leeches constitutes seven identified pairs of segmental heart interneurons. Four identified pairs of heart interneurons make a staggered pattern of inhibitory synaptic connections with segmental heart motor neurons. Using extracellular recording from multiple interneurons in the network in 56 isolated nerve cords, we show that this pattern generator produces a side-to-side asymmetric pattern of intersegmental coordination among ipsilateral premotor interneurons. This pattern corresponds to a similarly asymmetric fictive motor pattern in heart motor neurons and asymmetric constriction pattern of the two tubular hearts, synchronous and peristaltic. We provide a quantitative description of the firing pattern of all the premotor interneurons, including phase, duty cycle, and intraburst frequency of this premotor activity pattern. This analysis identifies two stereotypical coordination modes corresponding to synchronous and peristaltic, which show phase constancy over a broad range of periods as do the fictive motor pattern and the heart constriction pattern. Coordination mode is controlled through one segmental pair of heart interneurons (switch interneurons). Side-to-side switches in coordination mode are a regular feature of this pattern generator and occur with changes in activity state of these switch interneurons. Associated with synchronous coordination of premotor interneurons, the ipsilateral switch interneuron is in an active state, during which it produces rhythmic bursts, whereas associated with peristaltic coordination, the ipsilateral switch interneuron is largely silent. We argue that timing and pattern elaboration are separate functions produced by overlapping subnetworks in the heartbeat central pattern generator. PMID:16611849

  2. Dynamic labyrinthine pattern in an active liquid film.

    PubMed

    Chen, Yong-Jun; Nagamine, Yuko; Yoshikawa, Kenichi

    2009-11-01

    We report the generation of a dynamic labyrinthine pattern in an active alcohol film. A dynamic labyrinthine pattern is formed along the contact line of air/pentanol/aqueous three phases. The contact line shows a clear time-dependent change with regard to both perimeter and area of a domain. An autocorrelation analysis of time development of the dynamics of the perimeter and area revealed a strong geometric correlation between neighboring patterns. The pattern showed autoregressive behavior. The behavior of the dynamic pattern is strikingly different from those of stationary labyrinthine patterns. The essential aspects of the observed dynamic pattern are reproduced by a diffusion-controlled geometric model. PMID:20365076

  3. Air pollution exposure: An activity pattern approach for active transportation

    NASA Astrophysics Data System (ADS)

    Adams, Matthew D.; Yiannakoulias, Nikolaos; Kanaroglou, Pavlos S.

    2016-09-01

    In this paper, we demonstrate the calculation of personal air pollution exposure during trips made by active transportation using activity patterns without personal monitors. We calculate exposure as the inhaled dose of particulate matter 2.5 μg or smaller. Two modes of active transportation are compared, and they include cycling and walking. Ambient conditions are calculated by combining mobile and stationary monitoring data in an artificial neural network space-time model. The model uses a land use regression framework and has a prediction accuracy of R2 = 0.78. Exposure is calculated at 10 m or shorter intervals during the trips using inhalation rates associated with both modes. The trips are children's routes between home and school. The average dose during morning cycling trips was 2.17 μg, during morning walking trips was 3.19 μg, during afternoon cycling trips was 2.19 μg and during afternoon walking trips was 3.23 μg. The cycling trip dose was significantly lower than the walking trip dose. The air pollution exposure during walking or cycling trips could not be strongly predicted by either the school or household ambient conditions, either individually or in combination. Multiple linear regression models regressing both the household and school ambient conditions against the dose were only able to account for, at most, six percent of the variance in the exposure. This paper demonstrates that incorporating activity patterns when calculating exposure can improve the estimate of exposure compared to its calculation from ambient conditions.

  4. a Multidisciplinary Analytical Framework for Studying Active Mobility Patterns

    NASA Astrophysics Data System (ADS)

    Orellana, D.; Hermida, C.; Osorio, P.

    2016-06-01

    Intermediate cities are urged to change and adapt their mobility systems from a high energy-demanding motorized model to a sustainable low-motorized model. In order to accomplish such a model, city administrations need to better understand active mobility patterns and their links to socio-demographic and cultural aspects of the population. During the last decade, researchers have demonstrated the potential of geo-location technologies and mobile devices to gather massive amounts of data for mobility studies. However, the analysis and interpretation of this data has been carried out by specialized research groups with relatively narrow approaches from different disciplines. Consequently, broader questions remain less explored, mainly those relating to spatial behaviour of individuals and populations with their geographic environment and the motivations and perceptions shaping such behaviour. Understanding sustainable mobility and exploring new research paths require an interdisciplinary approach given the complex nature of mobility systems and their social, economic and environmental impacts. Here, we introduce the elements for a multidisciplinary analytical framework for studying active mobility patterns comprised of three components: a) Methodological, b) Behavioural, and c) Perceptual. We demonstrate the applicability of the framework by analysing mobility patterns of cyclists and pedestrians in an intermediate city integrating a range of techniques, including: GPS tracking, spatial analysis, auto-ethnography, and perceptual mapping. The results demonstrated the existence of non-evident spatial behaviours and how perceptual features affect mobility. This knowledge is useful for developing policies and practices for sustainable mobility planning.

  5. Oscillatory Dynamics Related to the Unagreement Pattern in Spanish

    ERIC Educational Resources Information Center

    Perez, Alejandro; Molinaro, Nicola; Mancini, Simona; Barraza, Paulo; Carreiras, Manuel

    2012-01-01

    Unagreement patterns consist in a person feature mismatch between subject and verb that is nonetheless grammatical in Spanish. The processing of this type of construction gives new insights into the understanding of agreement processes during language comprehension. Here, we contrasted oscillatory brain activity triggered by Unagreement in…

  6. Relative Pitch Perception and the Detection of Deviant Tone Patterns.

    PubMed

    Denham, Susan L; Coath, Martin; Háden, Gábor P; Murray, Fiona; Winkler, István

    2016-01-01

    Most people are able to recognise familiar tunes even when played in a different key. It is assumed that this depends on a general capacity for relative pitch perception; the ability to recognise the pattern of inter-note intervals that characterises the tune. However, when healthy adults are required to detect rare deviant melodic patterns in a sequence of randomly transposed standard patterns they perform close to chance. Musically experienced participants perform better than naïve participants, but even they find the task difficult, despite the fact that musical education includes training in interval recognition.To understand the source of this difficulty we designed an experiment to explore the relative influence of the size of within-pattern intervals and between-pattern transpositions on detecting deviant melodic patterns. We found that task difficulty increases when patterns contain large intervals (5-7 semitones) rather than small intervals (1-3 semitones). While task difficulty increases substantially when transpositions are introduced, the effect of transposition size (large vs small) is weaker. Increasing the range of permissible intervals to be used also makes the task more difficult. Furthermore, providing an initial exact repetition followed by subsequent transpositions does not improve performance. Although musical training correlates with task performance, we find no evidence that violations to musical intervals important in Western music (i.e. the perfect fifth or fourth) are more easily detected. In summary, relative pitch perception does not appear to be conducive to simple explanations based exclusively on invariant physical ratios. PMID:27080682

  7. Implicationally Related Error Patterns and the Selection of Treatment Targets.

    ERIC Educational Resources Information Center

    Dinnsen, Daniel A.; O'Connor, Kathleen M.

    2001-01-01

    This article compares different claims that have been made concerning acquisition by transitional rule-based derivation theories and by optimality theory. Case studies of children with phonological delays are examined. Error patterns are argued to be implicationally related and optimality theory is shown to offer a principled explanation.…

  8. Relational Reasoning in Medical Education: Patterns in Discourse and Diagnosis

    ERIC Educational Resources Information Center

    Dumas, Denis; Alexander, Patricia A.; Baker, Lisa M.; Jablansky, Sophie; Dunbar, Kevin N.

    2014-01-01

    Relational reasoning, which has been defined as the ability to discern meaningful patterns within any informational stream, is a foundational cognitive ability associated with education, including in scientific domains. This study entailed the analysis of instructional conversations in which an attending clinical neurologist and his team of…

  9. Foreshock activity related to enhanced aftershock production

    NASA Astrophysics Data System (ADS)

    Marsan, D.; Helmstetter, A.; Bouchon, M.; Dublanchet, P.

    2014-10-01

    Foreshock activity sometimes precedes the occurrence of large earthquakes, but the nature of this seismicity is still debated, and whether it marks transient deformation and/or slip nucleation is still unclear. We here study at the worldwide scale how foreshock occurrence affects the postseismic phase and find a significant positive correlation between foreshock and aftershock activities: earthquakes preceded by accelerating seismicity rates produce 40% more aftershocks on average, and the length of the aftershock zone after 20 days is 20% larger. These observations cannot be reproduced by standard earthquake clustering models that predict the accelerating pattern of foreshock occurrence but not its impact on aftershock activity. This strongly suggests that slow deformation transients, possibly related to episodic creep, could initiate prior to the main shock and extend past the coseismic phase, resulting in compound ruptures that include a very long period (up to tens of days) component.

  10. Healthy and unhealthy dietary patterns are related to pre-diabetes: a case-control study.

    PubMed

    Bagheri, Fariba; Siassi, Fereydoun; Koohdani, Fariba; Mahaki, Behzad; Qorbani, Mostafa; Yavari, Parvaneh; Shaibu, Osman Mohammed; Sotoudeh, Gity

    2016-09-01

    Pre-diabetes increases the risk of diabetes and CVD. Several studies have investigated the relationship between food intake and pre-diabetes morbidity, but the dietary patterns of pre-diabetes subjects were not taken into consideration. The aim of this study was to determine the relationship between dietary patterns and pre-diabetes. In this regard, 150 pre-diabetic subjects and 150 healthy controls, who attended the diabetes screening centre in Shahreza, Iran, were matched for age group and sex. The weight, height, waist circumference, physical activity, systolic and diastolic blood pressures, and blood glucose levels of all participants were measured. Dietary information was collected using a semi-quantitative FFQ. Using factor analysis, two dietary patterns were identified: the vegetables, fruits and legumes (VFL) dietary pattern and the sweet, solid fat, meat and mayonnaise (SSMM) dietary pattern. Multivariate logistic regression was used to assess the relationship between pre-diabetes and dietary patterns. After adjusting for age, education, physical activity, BMI and energy intake, the VFL dietary pattern was found to be negatively associated with lower pre-diabetes (OR 0·16; 95 % CI 0·10, 0·26). Furthermore, the SSMM dietary pattern was positively associated with pre-diabetes (OR 5·45; 95 % CI 3·22, 9·23). In conclusion, the VFL dietary pattern is inversely related to pre-diabetes, whereas the SSMM dietary pattern is associated with increased risk of pre-diabetes. PMID:27451983

  11. Activity recognition using correlated pattern mining for people with dementia.

    PubMed

    Sim, Kelvin; Phua, Clifton; Yap, Ghim-Eng; Biswas, Jit; Mokhtari, Mounir

    2011-01-01

    Due to the rapidly aging population around the world, senile dementia is growing into a prominent problem in many societies. To monitor the elderly dementia patients so as to assist them in carrying out their basic Activities of Daily Living (ADLs) independently, sensors are deployed in their homes. The sensors generate a stream of context information, i.e., snippets of the patient's current happenings, and pattern mining techniques can be applied to recognize the patient's activities based on these micro contexts. Most mining techniques aim to discover frequent patterns that correspond to certain activities. However, frequent patterns can be poor representations of activities. In this paper, instead of using frequent patterns, we propose using correlated patterns to represent activities. Using simulation data collected in a smart home testbed, our experimental results show that using correlated patterns rather than frequent ones improves the recognition performance by 35.5% on average. PMID:22256096

  12. Patterns of Activity Revealed by a Time Lag Analysis of a Model Active Region

    NASA Astrophysics Data System (ADS)

    Bradshaw, Stephen; Viall, Nicholeen

    2016-05-01

    We investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of average frequencies. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine an extrapolated magnetic skeleton with hydrodynamic and forward modeling codes to create a model active region, and apply the time lag method to synthetic observations. Our aim is to recover some typical properties and patterns of activity observed in active regions. Our key findings are: 1. Cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. 2. Shorter coronal loops in the core cool more quickly than longer loops at the periphery. 3. All channel pairs show zero time lag when the line-of-sight passes through coronal loop foot-points. 4. There is strong evidence that plasma must be re-energized on a time scale comparable to the cooling timescale to reproduce the observed coronal activity, but it is likely that a relatively broad spectrum of heating frequencies operates across active regions. 5. Due to their highly dynamic nature, we find nanoflare trains produce zero time lags along entire flux tubes in our model active region that are seen between the same channel pairs in observed active regions.

  13. Universal 2-layered noniterative perceptron for recognizing closely related patterns

    NASA Astrophysics Data System (ADS)

    Hu, Chia-Lun J.

    2000-08-01

    As we published in the last eight years, when the analog-to- binary mapping of any M training CLASS patterns are not PLI, then a one-layered preceptron (OLP) just cannot learn this mapping at all no matter what learning rule we use, because the solution of the connection matrix does not exist. However, as we derived form this PLI condition, which is the most general separability condition for an OLP, a PCTLP system can still be used to separate these closely relate and 'inseparable' patterns according to the targeted outputs Vm. This paper repots the theory and the design of this NOVEL PCTLP system.

  14. Relating Spatial Patterns in Image Data to Scene Characteristics

    NASA Technical Reports Server (NTRS)

    Strahler, A. H.; Woodcock, C. E.

    1983-01-01

    In remote sensing, the primary goal is accurate scene inference, in which characteristics of the scene are inferred from the image data. More effective inference of scene characteristics can be accomplished through the use of techniques that use explicit models of spatial pattern. Spatial patterns in image data are functionally related to the size and spacing of elements in the scene and to the spatial resolution of the image data. At resolutions where variance is high, scene inference techniques should rely heavily on data from the spatial domain. As variance decreases, effective scene inference will increasingly rely on spectral data.

  15. Neuromuscular activation patterns during treadmill walking after space flight

    NASA Technical Reports Server (NTRS)

    Layne, C. S.; McDonald, P. V.; Bloomberg, J. J.

    1997-01-01

    Astronauts adopt a variety of neuromuscular control strategies during space flight that are appropriate for locomoting in that unique environment, but are less than optimal upon return to Earth. We report here the first systematic investigation of potential adaptations in neuromuscular activity patterns associated with postflight locomotion. Astronaut-subjects were tasked with walking on a treadmill at 6.4 km/h while fixating a visual target 30 cm away from their eyes after space flights of 8-15 days. Surface electromyography was collected from selected lower limb muscles and normalized with regard to mean amplitude and temporal relation to heel strike. In general, high correlations (more than 0.80) were found between preflight and postflight activation waveforms for each muscle and each subject: however relative activation amplitude around heel strike and toe off was changed as a result of flight. The level of muscle cocontraction and activation variability, and the relationship between the phasic characteristics of the ankle musculature in preparation for toe off also were altered by space flight. Subjects also reported oscillopsia during treadmill walking after flight. These findings indicate that, after space flight, the sensory-motor system can generate neuromuscular-activation strategies that permit treadmill walking, but subtle changes in lower-limb neuromuscular activation are present that may contribute to increased lower limb kinematic variability and oscillopsia also present during postflight walking.

  16. Patterns of Activity in a Global Model of a Solar Active Region

    NASA Astrophysics Data System (ADS)

    Bradshaw, S. J.; Viall, N. M.

    2016-04-01

    In this work we investigate the global activity patterns predicted from a model active region heated by distributions of nanoflares that have a range of frequencies. What differs is the average frequency of the distributions. The activity patterns are manifested in time lag maps of narrow-band instrument channel pairs. We combine hydrodynamic and forward modeling codes with a magnetic field extrapolation to create a model active region and apply the time lag method to synthetic observations. Our aim is not to reproduce a particular set of observations in detail, but to recover some typical properties and patterns observed in active regions. Our key findings are the following. (1) Cooling dominates the time lag signature and the time lags between the channel pairs are generally consistent with observed values. (2) Shorter coronal loops in the core cool more quickly than longer loops at the periphery. (3) All channel pairs show zero time lag when the line of sight passes through coronal loop footpoints. (4) There is strong evidence that plasma must be re-energized on a timescale comparable to the cooling timescale to reproduce the observed coronal activity, but it is likely that a relatively broad spectrum of heating frequencies are operating across active regions. (5) Due to their highly dynamic nature, we find nanoflare trains produce zero time lags along entire flux tubes in our model active region that are seen between the same channel pairs in observed active regions.

  17. Central circuits mediating patterned autonomic activity during active vs. passive emotional coping.

    PubMed

    Bandler, R; Keay, K A; Floyd, N; Price, J

    2000-09-01

    Animals, including humans, react with distinct emotional coping strategies to different sets of environmental demands. These strategies include the capacity to affect appropriate responses to "escapable" or "inescapable" stressors. Active emotional coping strategies--fight or flight--are particularly adaptive if the stress is escapable. On the other hand, passive emotional coping strategies-quiescence, immobility, decreased responsiveness to the environment-are useful when the stress is inescapable. Passive strategies contribute also to facilitating recovery and healing once the stressful event is over. Active vs. passive emotional coping strategies are characterised further by distinct patterns of autonomic change. Active strategies are associated with sympathoexcitation (hypertension, tachycardia), whereas passive strategies are associated with sympathoinhibitory patterns (hypotension, bradycardia). Distinct neural substrates mediating active vs. passive emotional coping have been identified within the longitudinal neuronal columns of the midbrain periaqueductal gray region (PAG). The PAG offers then a potentially useful point of entry for delineating neural circuits mediating the different forms of emotional coping and their associated patterns of autonomic activity. As one example, recent studies of the connections of orbital and medial prefrontal cortical (PFC) fields with specific PAG longitudinal neuronal columns are reviewed. Findings of discrete orbital and medial PFC projections to different PAG columns, and related PFC and PAG columnar connections with specific subregions of the hypothalamus, suggest that distinct but parallel circuits mediate the behavioural strategies and patterns of autonomic activity characteristic of emotional "engagement with" or "disengagement from" the external environment. PMID:11033213

  18. Complex genetic patterns in closely related colonizing invasive species

    PubMed Central

    Zhan, Aibin; Darling, John A; Bock, Dan G; Lacoursière-Roussel, Anaïs; MacIsaac, Hugh J; Cristescu, Melania E

    2012-01-01

    Anthropogenic activities frequently result in both rapidly changing environments and translocation of species from their native ranges (i.e., biological invasions). Empirical studies suggest that many factors associated with these changes can lead to complex genetic patterns, particularly among invasive populations. However, genetic complexities and factors responsible for them remain uncharacterized in many cases. Here, we explore these issues in the vase tunicate Ciona intestinalis (Ascidiacea: Enterogona: Cionidae), a model species complex, of which spA and spB are rapidly spreading worldwide. We intensively sampled 26 sites (N = 873) from both coasts of North America, and performed phylogenetic and population genetics analyses based on one mitochondrial fragment (cytochrome c oxidase subunit 3–NADH dehydrogenase subunit I, COX3-ND1) and eight nuclear microsatellites. Our analyses revealed extremely complex genetic patterns in both species on both coasts. We detected a contrasting pattern based on the mitochondrial marker: two major genetic groups in C. intestinalis spA on the west coast versus no significant geographic structure in C. intestinalis spB on the east coast. For both species, geo-graphically distant populations often showed high microsatellite-based genetic affinities whereas neighboring ones often did not. In addition, mitochondrial and nuclear markers provided largely inconsistent genetic patterns. Multiple factors, including random genetic drift associated with demographic changes, rapid selection due to strong local adaptation, and varying propensity for human-mediated propagule dispersal could be responsible for the observed genetic complexities. PMID:22957143

  19. Changes in disease patterns and related social trends.

    PubMed

    Powles, J

    1992-08-01

    Both the material and non-material aspects of social life are viewed as determinants of major transformations in the patterns of fatal disease and injury. A 'worst case' scenario for the burden of fatal disease is taken as a poor agrarian society precariously dependent on starchy staples and a narrow range of other foods. In such a society life expectancy may be as low as 20. However in many 'pre-modern' societies the regime of roughly matching fertility and mortality levels was set at a 'submaximal' level, with completed fertility rates moderated by marriage conventions. The relative importance of the factors contributing to the historical decline in fatal infection continues to be debated. Evidence on the central role of maternal literacy in the recent decline in Third World mortality suggests the importance of changes in the body of civil society as well as the activities of professionals and public agencies. The decline in fatal infections has been offset to varying extents by an increase in non-communicable disease (NCD): the Mediterranean and East Asia having smaller epidemics of NCDs and Eastern Europe having sustained rises of NCDs. Most industrialised countries have experienced declines in overall NCD mortality in the last 2 decades. Both the fall in fatal infection and the rise and early fall of NCDs can usefully be viewed against the baseline of hunter gatherer cultures. When this is done, the relationship between economic development and disease is seen to be complex. Much 'progress' has been achieved by countering (and then doing better than countering) the adverse effects of earlier developments. Although most members of the generation now alive have experienced marked health benefits from economic and technical advance, it is unclear whether these gains can be both sustained and generalised. It is possible that adverse lagged effects of current industrial (and military) activities will disrupt the habitat of future generations of our species through

  20. Temporal patterns of deer-vehicle collisions consistent with deer activity pattern and density increase but not general accident risk.

    PubMed

    Hothorn, Torsten; Müller, Jörg; Held, Leonhard; Möst, Lisa; Mysterud, Atle

    2015-08-01

    The increasing number of deer-vehicle collisions (DVCs) across Europe during recent decades poses a serious threat to human health and animal welfare and increasing costs for society. DVCs are triggered by both a human-related and a deer-related component. Mitigation requires an understanding of the processes driving temporal and spatial collision patterns. Separating human-related from deer-related processes is important for identifying potentially effective countermeasures, but this has rarely been done. We analysed two time series of 341,655 DVCs involving roe deer and 854,659 non-deer-related accidents (non-DVCs) documented between 2002 and 2011. Nonparametric smoothing and temporal parametric modelling were used to estimate annual, seasonal, weekly and diurnal patterns in DVCs, non-DVCs and adjusted DVCs. As we had access to data on both DVCs and non-DVCs, we were able to disentangle the relative role of human-related and deer-related processes contributing to the overall temporal DVC pattern. We found clear evidence that variation in DVCs was mostly driven by deer-related and not human-related activity on annual, seasonal, weekly and diurnal scales. A very clear crepuscular activity pattern with high activity after sunset and around sunrise throughout the year was identified. Early spring and the mating season between mid-July and mid-August are typically periods of high roe deer activity, and as expected we found a high number of DVC during these periods, although these patterns differed tremendously during different phases of a day. The role of human activity was mainly reflected in fewer DVCs on weekends than on weekdays. Over the ten-year study period, we estimated that DVCs increased by 25%, whereas the number of non-DVCs decreased by 10%. Increasing deer densities are the most likely driver behind this rise in DVCs. Precise estimates of DVC patterns and their relationship to deer and human activity patterns allow implementation of specific mitigation

  1. Patterns of activity expressed by juvenile horseshoe crabs.

    PubMed

    Dubofsky, E A; Simpson, S D; Chabot, Christopher C; Watson, Winsor H

    2013-09-01

    Adult American horseshoe crabs, Limulus polyphemus, possess endogenous circadian and circatidal clocks controlling visual sensitivity and locomotion, respectively. The goal of this study was to determine the types of activity rhythms expressed by juvenile horseshoe crabs (n = 24) when exposed to a 14:10 light/dark cycle (LD) for 10 days, followed by 10 days of constant darkness (DD). Horseshoe crab activity was recorded with a digital time-lapse video system that used an infrared-sensitive camera so animals could be monitored at night. In LD, 15 animals expressed daily patterns of activity, 6 displayed a circatidal pattern, and the remaining 3 were arrhythmic. Of the 15 animals with daily patterns of locomotion, 7 had a significant preference (P < 0.05) for diurnal activity and 3 for nocturnal activity; the remainder did not express a significant preference for day or night activity. In DD, 13 horseshoe crabs expressed circatidal rhythms and 8 maintained a pattern of about 24 h. Although these results suggest the presence of a circadian clock influencing circatidal patterns of locomotion, these apparent circadian rhythms may actually represent the expression of just one of the two bouts of activity driven by the putative circalunidian clocks that control their tidal rhythms. Overall, these results indicate that, like adults, juvenile horseshoe crabs express both daily and tidal patterns of activity and that at least one, and maybe both, of these patterns is driven by endogenous clocks. PMID:24088795

  2. Mammalian Rest/Activity Patterns Explained by Physiologically Based Modeling

    PubMed Central

    Phillips, A. J. K.; Fulcher, B. D.; Robinson, P. A.; Klerman, E. B.

    2013-01-01

    Circadian rhythms are fundamental to life. In mammals, these rhythms are generated by pacemaker neurons in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN is remarkably consistent in structure and function between species, yet mammalian rest/activity patterns are extremely diverse, including diurnal, nocturnal, and crepuscular behaviors. Two mechanisms have been proposed to account for this diversity: (i) modulation of SCN output by downstream nuclei, and (ii) direct effects of light on activity. These two mechanisms are difficult to disentangle experimentally and their respective roles remain unknown. To address this, we developed a computational model to simulate the two mechanisms and their influence on temporal niche. In our model, SCN output is relayed via the subparaventricular zone (SPZ) to the dorsomedial hypothalamus (DMH), and thence to ventrolateral preoptic nuclei (VLPO) and lateral hypothalamus (LHA). Using this model, we generated rich phenotypes that closely resemble experimental data. Modulation of SCN output at the SPZ was found to generate a full spectrum of diurnal-to-nocturnal phenotypes. Intriguingly, we also uncovered a novel mechanism for crepuscular behavior: if DMH/VLPO and DMH/LHA projections act cooperatively, daily activity is unimodal, but if they act competitively, activity can become bimodal. In addition, we successfully reproduced diurnal/nocturnal switching in the rodent Octodon degu using coordinated inversions in both masking and circadian modulation. Finally, the model correctly predicted the SCN lesion phenotype in squirrel monkeys: loss of circadian rhythmicity and emergence of ∼4-h sleep/wake cycles. In capturing these diverse phenotypes, the model provides a powerful new framework for understanding rest/activity patterns and relating them to underlying physiology. Given the ubiquitous effects of temporal organization on all aspects of animal behavior and physiology, this study sheds light on the physiological

  3. The Influence of Epoch Length on Physical Activity Patterns Varies by Child's Activity Level

    ERIC Educational Resources Information Center

    Nettlefold, Lindsay; Naylor, P. J.; Warburton, Darren E. R.; Bredin, Shannon S. D.; Race, Douglas; McKay, Heather A.

    2016-01-01

    Purpose: Patterns of physical activity (PA) and sedentary time, including volume of bouted activity, are important health indicators. However, the effect of accelerometer epoch length on measurement of these patterns and associations with health outcomes in children remain unknown. Method: We measured activity patterns in 308 children (52% girls,…

  4. Code-Switching Patterns in the Writing-Related Talk of Young Emergent Bilinguals

    ERIC Educational Resources Information Center

    Gort, Mileidis

    2012-01-01

    This qualitative study examined code-switching patterns in the writing-related talk of 6 emergent Spanish-English bilingual first-grade children. Audio recordings, field notes, and writing artifacts documenting participant activities and language use in Spanish and English writing workshops were gathered over the course of 6 months and analyzed…

  5. Cortical activity patterns predict robust speech discrimination ability in noise

    PubMed Central

    Shetake, Jai A.; Wolf, Jordan T.; Cheung, Ryan J.; Engineer, Crystal T.; Ram, Satyananda K.; Kilgard, Michael P.

    2012-01-01

    The neural mechanisms that support speech discrimination in noisy conditions are poorly understood. In quiet conditions, spike timing information appears to be used in the discrimination of speech sounds. In this study, we evaluated the hypothesis that spike timing is also used to distinguish between speech sounds in noisy conditions that significantly degrade neural responses to speech sounds. We tested speech sound discrimination in rats and recorded primary auditory cortex (A1) responses to speech sounds in background noise of different intensities and spectral compositions. Our behavioral results indicate that rats, like humans, are able to accurately discriminate consonant sounds even in the presence of background noise that is as loud as the speech signal. Our neural recordings confirm that speech sounds evoke degraded but detectable responses in noise. Finally, we developed a novel neural classifier that mimics behavioral discrimination. The classifier discriminates between speech sounds by comparing the A1 spatiotemporal activity patterns evoked on single trials with the average spatiotemporal patterns evoked by known sounds. Unlike classifiers in most previous studies, this classifier is not provided with the stimulus onset time. Neural activity analyzed with the use of relative spike timing was well correlated with behavioral speech discrimination in quiet and in noise. Spike timing information integrated over longer intervals was required to accurately predict rat behavioral speech discrimination in noisy conditions. The similarity of neural and behavioral discrimination of speech in noise suggests that humans and rats may employ similar brain mechanisms to solve this problem. PMID:22098331

  6. Cannabinoid Receptor Activation Shifts Temporally Engendered Patterns of Dopamine Release

    PubMed Central

    Oleson, Erik B; Cachope, Roger; Fitoussi, Aurelie; Tsutsui, Kimberly; Wu, Sharon; Gallegos, Jacqueline A; Cheer, Joseph F

    2014-01-01

    The ability to discern temporally pertinent environmental events is essential for the generation of adaptive behavior in conventional tasks, and our overall survival. Cannabinoids are thought to disrupt temporally controlled behaviors by interfering with dedicated brain timing networks. Cannabinoids also increase dopamine release within the mesolimbic system, a neural pathway generally implicated in timing behavior. Timing can be assessed using fixed-interval (FI) schedules, which reinforce behavior on the basis of time. To date, it remains unknown how cannabinoids modulate dopamine release when responding under FI conditions, and for that matter, how subsecond dopamine release is related to time in these tasks. In the present study, we hypothesized that cannabinoids would accelerate timing behavior in an FI task while concurrently augmenting a temporally relevant pattern of dopamine release. To assess this possibility, we measured subsecond dopamine concentrations in the nucleus accumbens while mice responded for food under the influence of the cannabinoid agonist WIN 55 212-2 in an FI task. Our data reveal that accumbal dopamine concentrations decrease proportionally to interval duration—suggesting that dopamine encodes time in FI tasks. We further demonstrate that WIN 55 212-2 dose-dependently increases dopamine release and accelerates a temporal behavioral response pattern in a CB1 receptor-dependent manner—suggesting that cannabinoid receptor activation modifies timing behavior, in part, by augmenting time-engendered patterns of dopamine release. Additional investigation uncovered a specific role for endogenous cannabinoid tone in timing behavior, as elevations in 2-arachidonoylglycerol, but not anandamide, significantly accelerated the temporal response pattern in a manner akin to WIN 55 212-2. PMID:24345819

  7. Headaches related to sexual activity.

    PubMed Central

    Lance, J W

    1976-01-01

    Twenty-one patients experienced headache related to sexual activity. Two varieties of headache could be distinguished from the clinical histories. The first, developing as sexual excitement mount, had the characteristics of muscle contraction headache. The second, severe, throbbing or 'explosive' in character, occurring at the time of orgasm, was presumably of vascular origin associated with a hyperdynamic circulatory state. Two of the patients with the latter type of headache had each experienced episodes of cerebral vascular insufficiency on one occasion which subsequently resolved. A third patient in this category had a past history of drop attacks. No evidence of any structural lesion was obtained on clinical examination or investigation, including cerebral angiography in seven patients. Eighteen patients have been followed up for periods of two to seven years without any serious intracranial disorder becoming apparent. While the possibility of intracranial vascular or other lesions must always be borne in mind, there appears to be a syndrome of headache associated with sexual excitement where no organic change can be demonstrated, analogous to benign cough headache and benign exertional headache. PMID:1011034

  8. Dispersal patterns of red foxes relative to population density

    USGS Publications Warehouse

    Allen, S.H.; Sargeant, A.B.

    1993-01-01

    Factors affecting red fox (Vulpes vulpes) dispersal patterns are poorly understood but warranted investigation because of the role of dispersal in rebuilding depleted populations and transmission of diseases. We examined dispersal patterns of red foxes in North Dakota based on recoveries of 363 of 854 foxes tagged as pups and relative to fox density. Foxes were recovered up to 8.6 years after tagging; 79% were trapped or shot. Straight-line distances between tagging and recovery locations ranged from 0 to 302 km. Mean recovery distances increased with age and were greater for males than females, but longest individual recovery distances were by females. Dispersal distances were not related to population density for males (P = 0.36) or females (P = 0.96). The proportion of males recovered that dispersed was inversely related to population density (r = -0.94; n = 5; P = 0.02), but not the proportion of females (r = -0.49; n = 5; P = 0.40). Dispersal directions were not uniform for either males (P = 0.003) or females (P = 0.006); littermates tended to disperse in similar directions (P = 0.09). A 4-lane interstate highway altered dispersal directions (P = 0.001). Dispersal is a strong innate behavior of red foxes (especially males) that results in many individuals of both sexes traveling far from natal areas. Because dispersal distance was unaffected by fox density, populations can be rebuilt and diseases transmitted long distances regardless of fox abundance.

  9. Cognitive Aging: Activity Patterns and Maintenance Intentions

    ERIC Educational Resources Information Center

    Gilhooly, K. J.; Gilhooly, M. L.; Phillips, L. H.; Harvey, D.; Murray, A.; Hanlon, P.

    2007-01-01

    This study examined relationships between cognitive functioning in older people and (1) levels of mental, physical and social activities, and (2) intentions regarding maintenance of cognitive functioning. Participants (N = 145) were 70-91 years of age, varied in health status and socio-economic backgrounds. Current cognitive functioning was…

  10. Physical Activity Patterns of Young Women Post-College Graduation

    ERIC Educational Resources Information Center

    Soliah, LuAnn; Walter, Janelle; Antosh, Deeanna

    2008-01-01

    Americans need more physical activity in their daily routines. There are numerous physical as well as psychological benefits that can be credited to regular physical activity. The purpose of this research was to examine the physical activity patterns of young women, post-college graduation. The average woman in this study exercised 22 minutes per…

  11. Turing pattern formation in fractional activator-inhibitor systems.

    PubMed

    Henry, B I; Langlands, T A M; Wearne, S L

    2005-08-01

    Activator-inhibitor systems of reaction-diffusion equations have been used to describe pattern formation in numerous applications in biology, chemistry, and physics. The rate of diffusion in these applications is manifest in the single parameter of the diffusion constant, and stationary Turing patterns occur above a critical value of d representing the ratio of the diffusion constants of the inhibitor to the activator. Here we consider activator-inhibitor systems in which the diffusion is anomalous subdiffusion; the diffusion rates are manifest in both a diffusion constant and a diffusion exponent. A consideration of this problem in terms of continuous-time random walks with sources and sinks leads to a reaction-diffusion system with fractional order temporal derivatives operating on the spatial Laplacian. We have carried out an algebraic stability analysis of the homogeneous steady-state solution in fractional activator-inhibitor systems, with Gierer-Meinhardt reaction kinetics and with Brusselator reaction kinetics. For each class of reaction kinetics we identify a Turing instability bifurcation curve in the two-dimensional diffusion parameter space. The critical value of d , for Turing instabilities, decreases monotonically with the anomalous diffusion exponent between unity (standard diffusion) and zero (extreme subdiffusion). We have also carried out numerical simulations of the governing fractional activator-inhibitor equations and we show that the Turing instability precipitates the formation of complex spatiotemporal patterns. If the diffusion of the activator and inhibitor have the same anomalous scaling properties, then the surface profiles of these patterns for values of d slightly above the critical value varies from smooth stationary patterns to increasingly rough and nonstationary patterns as the anomalous diffusion exponent varies from unity towards zero. If the diffusion of the activator is anomalous subdiffusion but the diffusion of the inhibitor

  12. Mining continuous activity patterns from animal trajectory data

    USGS Publications Warehouse

    Wang, Y.; Luo, Ze; Baoping, Yan; Takekawa, John Y.; Prosser, Diann J.; Newman, Scott H.

    2014-01-01

    The increasing availability of animal tracking data brings us opportunities and challenges to intuitively understand the mechanisms of animal activities. In this paper, we aim to discover animal movement patterns from animal trajectory data. In particular, we propose a notion of continuous activity pattern as the concise representation of underlying similar spatio-temporal movements, and develop an extension and refinement framework to discover the patterns. We first preprocess the trajectories into significant semantic locations with time property. Then, we apply a projection-based approach to generate candidate patterns and refine them to generate true patterns. A sequence graph structure and a simple and effective processing strategy is further developed to reduce the computational overhead. The proposed approaches are extensively validated on both real GPS datasets and large synthetic datasets.

  13. Ground-squirrel mounds and related patterned ground along the San Andreas Fault in Central California

    USGS Publications Warehouse

    Wallace, Robert E.

    1991-01-01

    Extensive areas of mound topography and related patterned ground, apparently derived from the mounds of the California Ground Squirrel (Spermophilus beecheyi beecheyi), are in central California.  The relation of patterned ground to the San Andreas fault west of Bakersfield may provide insight into the timing of deformation along the fault as well as the history of ground squirrels.  Mound topography appears to have evolved through several stages from scattered mounds currently being constructed on newly deposited alluvial surfaces, to saturation of areas by mounds, followed by coalescence, elongation and lineation of the mounds.  Elongation, coalescence and modification of the mounds has been primarily by wind, but to a lesser extent by drainage and solifluction.  A time frame including ages of 4,000, 10,500, 29,000, and 73,000 years BP is derived by relating the patterns to slip on the San Andreas fault.  Further relating of the patterns to faulting, tilting, and warping may illuminate details of the rates and history of deformation.  Similarly, relating the patterns to the history of ground squirrel activity may help answer such problems as rates of dispersal and limits on population density.

  14. Cortical activity patterns predict speech discrimination ability

    PubMed Central

    Engineer, Crystal T; Perez, Claudia A; Chen, YeTing H; Carraway, Ryan S; Reed, Amanda C; Shetake, Jai A; Jakkamsetti, Vikram; Chang, Kevin Q; Kilgard, Michael P

    2010-01-01

    Neural activity in the cerebral cortex can explain many aspects of sensory perception. Extensive psychophysical and neurophysiological studies of visual motion and vibrotactile processing show that the firing rate of cortical neurons averaged across 50–500 ms is well correlated with discrimination ability. In this study, we tested the hypothesis that primary auditory cortex (A1) neurons use temporal precision on the order of 1–10 ms to represent speech sounds shifted into the rat hearing range. Neural discrimination was highly correlated with behavioral performance on 11 consonant-discrimination tasks when spike timing was preserved and was not correlated when spike timing was eliminated. This result suggests that spike timing contributes to the auditory cortex representation of consonant sounds. PMID:18425123

  15. Perceptual similarity of visual patterns predicts dynamic neural activation patterns measured with MEG.

    PubMed

    Wardle, Susan G; Kriegeskorte, Nikolaus; Grootswagers, Tijl; Khaligh-Razavi, Seyed-Mahdi; Carlson, Thomas A

    2016-05-15

    Perceptual similarity is a cognitive judgment that represents the end-stage of a complex cascade of hierarchical processing throughout visual cortex. Previous studies have shown a correspondence between the similarity of coarse-scale fMRI activation patterns and the perceived similarity of visual stimuli, suggesting that visual objects that appear similar also share similar underlying patterns of neural activation. Here we explore the temporal relationship between the human brain's time-varying representation of visual patterns and behavioral judgments of perceptual similarity. The visual stimuli were abstract patterns constructed from identical perceptual units (oriented Gabor patches) so that each pattern had a unique global form or perceptual 'Gestalt'. The visual stimuli were decodable from evoked neural activation patterns measured with magnetoencephalography (MEG), however, stimuli differed in the similarity of their neural representation as estimated by differences in decodability. Early after stimulus onset (from 50ms), a model based on retinotopic organization predicted the representational similarity of the visual stimuli. Following the peak correlation between the retinotopic model and neural data at 80ms, the neural representations quickly evolved so that retinotopy no longer provided a sufficient account of the brain's time-varying representation of the stimuli. Overall the strongest predictor of the brain's representation was a model based on human judgments of perceptual similarity, which reached the limits of the maximum correlation with the neural data defined by the 'noise ceiling'. Our results show that large-scale brain activation patterns contain a neural signature for the perceptual Gestalt of composite visual features, and demonstrate a strong correspondence between perception and complex patterns of brain activity. PMID:26899210

  16. A Multiscale Survival Process for Modeling Human Activity Patterns

    PubMed Central

    Zhang, Tianyang; Cui, Peng; Song, Chaoming; Zhu, Wenwu; Yang, Shiqiang

    2016-01-01

    Human activity plays a central role in understanding large-scale social dynamics. It is well documented that individual activity pattern follows bursty dynamics characterized by heavy-tailed interevent time distributions. Here we study a large-scale online chatting dataset consisting of 5,549,570 users, finding that individual activity pattern varies with timescales whereas existing models only approximate empirical observations within a limited timescale. We propose a novel approach that models the intensity rate of an individual triggering an activity. We demonstrate that the model precisely captures corresponding human dynamics across multiple timescales over five orders of magnitudes. Our model also allows extracting the population heterogeneity of activity patterns, characterized by a set of individual-specific ingredients. Integrating our approach with social interactions leads to a wide range of implications. PMID:27023682

  17. Flow Pattern relative to the Substorm Current Wedge

    NASA Astrophysics Data System (ADS)

    Chu, X.; McPherron, R. L.; Hsu, T.

    2013-12-01

    Magnetospheric substorms play a key role in the coupling of the solar wind and the magnetosphere. The Substorm Current Wedge (SCW) is a key element in the present physical model of substorms. It is widely accepted that the SCW is created by earthward busty flows, but the generation mechanism is still unknown. Previous studies suggest pressure gradients and magnetic vortices are possible candidates. Due to the sparse coverage of satellites in space, these studies were strongly dependent on the assumption that the satellites were in the generation region of the field-aligned currents (FAC) forming the SCW. In this work, we take advantage of an inversion technique that determines the parameters describing the SCW and perform a statistical study on the plasma and magnetic field parameters of the flow pattern relative to the SCW. The inversion technique finds the location and the intensity of the SCW from midlatitude magnetic data. The technique has been validated using auroral observations, Equivalent Ionospheric Currents (EIC), SYM-H index from SuperMAG, and magnetic perturbations at geosynchronous orbit by the GOES satellite. A database of substorm events has been created using midlatitude positive bays, which are the ground signature of the SCW at lower latitudes. The inversion technique is applied to each event in the database to determine the location of the origin of the SCW. The inversion results are also used to find conjunction events with space observations from VAP (RBSP), THEMIS and GOES. The plasma and magnetic field parameters such as the pressure gradient and magnetic vorticity are then categorized as a function of their location relative to the origin of the SCW. How the distribution/pattern of the pressure gradient and vorticity are related to the properties of the SCW (locations and intensity of the FAC), and flows (entropy, velocity and density) will be determined.

  18. Extreme precipitation events and related weather patterns over Iraq

    NASA Astrophysics Data System (ADS)

    raheem Al-nassar, Ali; Sangrà, Pablo; Alarcón, Marta

    2016-04-01

    This study aims to investigate the extreme precipitation events and the associated weather phenomena in the Middle East and particularly in Iraq. For this purpose we used Baghdad daily precipitation records from the Iraqi Meteorological and Seismology Organization combined with ECMWF (ERA-Interim) reanalysis data for the period from January 2002 to December 2013. Extreme events were found statistically at the 90% percentile of the recorded precipitation, and were highly correlated with hydrological flooding in some cities of Iraq. We identified fifteen extreme precipitation events. The analysis of the corresponding weather patterns (500 hPa and 250 hPa geopotential and velocity field distribution) indicated that 5 events were related with cut off low causing the highest precipitation (180 mm), 3 events related with rex block (158 mm), 3 events related with jet streak occurrence (130 mm) and 4 events related with troughs (107 mm). . Five of these events caused flash floods and in particular one of them related with a rex block was the most dramatic heavy rain event in Iraq in 30 years. We investigated for each case the convective instability and dynamical forcing together with humidity sources. For convective instability we explored the distribution of the K index and SWEAT index. For dynamical forcing we analyzed at several levels Q vector, divergence, potential and relative vorticity advection and omega vertical velocity. Source of humidity was investigated through humidity and convergence of specific humidity distribution. One triggering factor of all the events is the advection and convergence of humidity from the Red Sea and the Persian Gulf. Therefore a necessary condition for extreme precipitation in Iraq is the advection and convergence of humidity from the Red Sea and Persian Gulf. Our preliminary analysis also indicates that extreme precipitation events are primary dynamical forced playing convective instability a secondary role.

  19. Leisure Activity Patterns and Marital Conflict in Iran

    PubMed Central

    Ahmadi, Khodabakhsh; Saadat, Hassan; Noushad, Siena

    2016-01-01

    Background: Over the past few decades, the association between leisure activity patterns and marital conflict or satisfaction has been studied extensively. However, most studies to date have been limited to middle-class families of developed societies, and an investigation of the issue, from a developing country perspective like Iran, is non-existent. Objectives: In an observational, analytical, cross-sectional study we aimed to investigate the relationship between leisure activity patterns and marital conflict in a nationally representative sample of Iranian married males. Patients and Methods: Using the cluster sampling method, a representative sample of 400 Iranian married individuals from seven provinces of Iran was surveyed. Self-administered surveys included a checklist collecting demographic and socioeconomic characteristics of the enrolled participants, leisure time questionnaire, and marital conflict questionnaire. The main patterns of leisure activity were derived from principal component analysis. For each pattern, factor scores were calculated. The relationship between factor scores and marital conflict were assessed using multivariate linear regression models accounting for the potential confounding effects of age, education, socioeconomic status, job status, number of children, duration of marriage, and time spent for leisure. Results: Two hundred and ninety-nine respondents completed the leisure time and marital conflict questionnaires. Five major leisure patterns were identified accounting for 60.3% of the variance in data. The most dominant pattern was family-oriented activities (e.g. spending time with family outdoors and spending time with family indoors) and was negatively linked to marital conflict (standardized beta= −0.154, P = 0.013). Of the four remaining patterns, three only included individual activities and one was a family-individual composite. Individual patterns exhibited discrepant behavior; while the pattern involving activities

  20. Patterns of relative species abundance in rainforests and coral reefs.

    PubMed

    Volkov, Igor; Banavar, Jayanth R; Hubbell, Stephen P; Maritan, Amos

    2007-11-01

    A formidable many-body problem in ecology is to understand the complex of factors controlling patterns of relative species abundance (RSA) in communities of interacting species. Unlike many problems in physics, the nature of the interactions in ecological communities is not completely known. Although most contemporary theories in ecology start with the basic premise that species interact, here we show that a theory in which all interspecific interactions are turned off leads to analytical results that are in agreement with RSA data from tropical forests and coral reefs. The assumption of non-interacting species leads to a sampling theory for the RSA that yields a simple approximation at large scales to the exact theory. Our results show that one can make significant theoretical progress in ecology by assuming that the effective interactions among species are weak in the stationary states in species-rich communities such as tropical forests and coral reefs. PMID:17972874

  1. Patterns of Children's Participation in Unorganized Physical Activity

    ERIC Educational Resources Information Center

    Findlay, Leanne C.; Garner, Rochelle E.; Kohen, Dafna E.

    2010-01-01

    Children's leisure-time or unorganized physical activity is associated with positive physical and mental health, yet there is little information available on tracking and predicting participation throughout the childhood and adolescent years. The purpose of the current study was to explore patterns of unorganized physical activity participation of…

  2. Physical Activity Patterns of Youth with Down Syndrome

    ERIC Educational Resources Information Center

    Esposito, Phil E.; MacDonald, Megan; Hornyak, Joseph E.; Ulrich, Dale A.

    2012-01-01

    The purpose of this study was to examine the physical activity patterns of children with Down syndrome. A cross-sectional approach and accelerometry were used to measure the time children with Down syndrome (N = 104) spent in sedentary, light, and moderate-to-vigorous physical activity. Results indicated that adolescents from ages 14 to 15 years…

  3. ELECTROMYOGRAPHIC ACTIVITY OF SCAPULAR MUSCLES DURING DIAGONAL PATTERNS USING ELASTIC RESISTANCE AND FREE WEIGHTS

    PubMed Central

    Talbott, Nancy; Kotowski, Susan

    2011-01-01

    Purpose/Background: Abnormalities in glenohumeral rhythm and neuromuscular control of the upper trapezius (UT), middle trapezius (MT), lower trapezius (LT) and serratus anterior (SA) muscles have been identified in individuals with shoulder pain. Upper extremity diagonal or proprioceptive neuromuscular facilitation (PNF) patterns have been suggested as effective means of activating scapular muscles, yet few studies have compared muscular activation during diagonal patterns with varying modes of resistance. The purpose of this study is to determine which type of resistance and PNF pattern combination best elicits electromyographic (EMG) activity of the scapular muscles. Methods: Twenty one healthy subjects with no history of scapulohumeral dysfunction were recruited from a population of convenience. Surface electrodes were applied to the SA, UT, MT and LT and EMG data collected for each muscle as the subject performed resisted UE D1 flexion, UE D1 extension, UE D2 flexion and UE D2 extension with elastic resistance and a three pound weight. Results: No significant differences were found between scapular muscle activity during D1 flexion when using elastic resistance and when using a weight. UT, MT and LT values were also not significantly different during D2 flexion when using elastic resistance vs. using a weight. The activity of the SA remained relatively the same during all patterns. The LT activity was significantly greater during D2 flexion with elastic resistance than during the D1 flexion and D1 extension with elastic resistance. MT activity was significantly greater during D2 flexion with elastic resistance as compared to all other patterns except D2 flexion with a weight. UT activity was significantly greater during flexion patterns than extension patterns. Conclusions: The upper extremity PNF pattern did significantly affect the mean UT, MT and LT activity but was not found to significantly affect SA activity. The type of resistance did not significantly

  4. fMRI activation patterns in an analytic reasoning task: consistency with EEG source localization

    NASA Astrophysics Data System (ADS)

    Li, Bian; Vasanta, Kalyana C.; O'Boyle, Michael; Baker, Mary C.; Nutter, Brian; Mitra, Sunanda

    2010-03-01

    Functional magnetic resonance imaging (fMRI) is used to model brain activation patterns associated with various perceptual and cognitive processes as reflected by the hemodynamic (BOLD) response. While many sensory and motor tasks are associated with relatively simple activation patterns in localized regions, higher-order cognitive tasks may produce activity in many different brain areas involving complex neural circuitry. We applied a recently proposed probabilistic independent component analysis technique (PICA) to determine the true dimensionality of the fMRI data and used EEG localization to identify the common activated patterns (mapped as Brodmann areas) associated with a complex cognitive task like analytic reasoning. Our preliminary study suggests that a hybrid GLM/PICA analysis may reveal additional regions of activation (beyond simple GLM) that are consistent with electroencephalography (EEG) source localization patterns.

  5. Activity patterns of bushbuck (Tragelaphus scriptus) in Queen Elizabeth National Park.

    PubMed

    Wronski, T; Apio, A; Plath, M

    2006-11-01

    Activity patterns and time budgets of bushbuck (Tragelaphus scriptus) were studied in a free-ranging population in Queen Elizabeth National Park, Uganda from August 2000 to January 2002. We investigated differences in activity patterns in relation to daytime, season, sun radiation, moonlight, age and sex. Bushbuck were found to show peak activities around sunrise and at dawn. No difference in the mean activity rates was found between the dry and wet season. Daytime activity was not predicted by differences in sun radiation, nor was nighttime activity predicted by the presence or absence of moonlight. We found the activity of adult territorial males to be strongly positively correlated with that of females, whereas the activity of young-adult non-territorial males was not significantly correlated with the activity of females. This suggests that young-adult males shift their peak activity to phases when adult territorial males are less active. PMID:16962727

  6. Connectivity, excitability and activity patterns in neuronal networks

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

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

  7. Learning causes reorganization of neuronal firing patterns to represent related experiences within a hippocampal schema.

    PubMed

    McKenzie, Sam; Robinson, Nick T M; Herrera, Lauren; Churchill, Jordana C; Eichenbaum, Howard

    2013-06-19

    According to schema theory as proposed by Piaget and Bartlett, learning involves the assimilation of new memories into networks of preexisting knowledge, as well as alteration of the original networks to accommodate the new information. Recent evidence has shown that rats form a schema of goal locations and that the hippocampus plays an essential role in adding new memories to the spatial schema. Here we examined the nature of hippocampal contributions to schema updating by monitoring firing patterns of multiple CA1 neurons as rats learned new goal locations in an environment in which there already were multiple goals. Before new learning, many neurons that fired on arrival at one goal location also fired at other goals, whereas ensemble activity patterns also distinguished different goal events, thus constituting a neural representation that linked distinct goals within a spatial schema. During new learning, some neurons began to fire as animals approached the new goals. These were primarily the same neurons that fired at original goals, the activity patterns at new goals were similar to those associated with the original goals, and new learning also produced changes in the preexisting goal-related firing patterns. After learning, activity patterns associated with the new and original goals gradually diverged, such that initial generalization was followed by a prolonged period in which new memories became distinguished within the ensemble representation. These findings support the view that consolidation involves assimilation of new memories into preexisting neural networks that accommodate relationships among new and existing memories. PMID:23785140

  8. Decoding the representation of numerical values from brain activation patterns.

    PubMed

    Damarla, Saudamini Roy; Just, Marcel Adam

    2013-10-01

    Human neuroimaging studies have increasingly converged on the possibility that the neural representation of specific numbers may be decodable from brain activity, particularly in parietal cortex. Multivariate machine learning techniques have recently demonstrated that the neural representation of individual concrete nouns can be decoded from fMRI patterns, and that some patterns are general over people. Here we use these techniques to investigate whether the neural codes for quantities of objects can be accurately decoded. The pictorial mode (nonsymbolic) depicted a set of objects pictorially (e.g., a picture of three tomatoes), whereas the digit-object mode depicted quantities as combination of a digit (e.g., 3) with a picture of a single object. The study demonstrated that quantities of objects were decodable from neural activation patterns, in parietal regions. These brain activation patterns corresponding to a given quantity were common across objects and across participants in the pictorial mode. Other important findings included better identification of individual numbers in the pictorial mode, partial commonality of neural patterns across the two modes, and hemispheric asymmetry with pictorially-depicted numbers represented bilaterally and numbers in the digit-object mode represented primarily in the left parietal regions. The findings demonstrate the ability to identify individual quantities of objects based on neural patterns, indicating the presence of stable neural representations of numbers. Additionally, they indicate a predominance of neural representation of pictorially depicted numbers over the digit-object mode. PMID:22505340

  9. Cortical motor activation patterns following hand transplantation and replantation.

    PubMed

    Brenneis, C; Löscher, W N; Egger, K E; Benke, T; Schocke, M; Gabl, M F; Wechselberger, G; Felber, S; Pechlaner, S; Margreiter, R; Piza-Katzer, H; Poewe, W

    2005-10-01

    We studied cortical activation patterns by functional MRI in a patient who received bilateral hand transplantation after amputation 6 years ago and in a patient who had received unilateral hand replantation within 2 hours after amputation. In the early postoperative period, the patient who had had the hand transplantation revealed strong activation of a higher motor area, only weak activation of the primary sensorimotor motor cortex and no activation of the primary somatosensory cortex. At 1-year follow-up, a small increase in primary sensorimotor motor cortex activation was observed. Activation of the primary somatosensory cortex was only seen at the 2 year follow-up. By contrast, after hand replantation, the activation pattern was similar to that of the uninjured hand within 6 weeks. This included activation of the primary sensorimotor motor cortex, higher motor areas and primary somatosensory cortex. Transplantation after long-standing amputation results in cortical reorganization occurring over a 2-year period. In contrast, hand replantation within a few hours preserves a normal activation pattern. PMID:16055246

  10. Agricultural activity shapes the communication and migration patterns in Senegal.

    PubMed

    Martin-Gutierrez, S; Borondo, J; Morales, A J; Losada, J C; Tarquis, A M; Benito, R M

    2016-06-01

    The communication and migration patterns of a country are shaped by its socioeconomic processes. The economy of Senegal is predominantly rural, as agriculture employs over 70% of the labor force. In this paper, we use mobile phone records to explore the impact of agricultural activity on the communication and mobility patterns of the inhabitants of Senegal. We find two peaks of phone calls activity emerging during the growing season. Moreover, during the harvest period, we detect an increase in the migration flows throughout the country. However, religious holidays also shape the mobility patterns of the Senegalese people. Hence, in the light of our results, agricultural activity and religious holidays are the primary drivers of mobility inside the country. PMID:27368795

  11. Agricultural activity shapes the communication and migration patterns in Senegal

    NASA Astrophysics Data System (ADS)

    Martin-Gutierrez, S.; Borondo, J.; Morales, A. J.; Losada, J. C.; Tarquis, A. M.; Benito, R. M.

    2016-06-01

    The communication and migration patterns of a country are shaped by its socioeconomic processes. The economy of Senegal is predominantly rural, as agriculture employs over 70% of the labor force. In this paper, we use mobile phone records to explore the impact of agricultural activity on the communication and mobility patterns of the inhabitants of Senegal. We find two peaks of phone calls activity emerging during the growing season. Moreover, during the harvest period, we detect an increase in the migration flows throughout the country. However, religious holidays also shape the mobility patterns of the Senegalese people. Hence, in the light of our results, agricultural activity and religious holidays are the primary drivers of mobility inside the country.

  12. Comparing Activity Patterns, Biological, and Family Factors in Children with and without Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    Beutum, Monique Natalie; Cordier, Reinie; Bundy, Anita

    2013-01-01

    The association between motor proficiency and moderate to vigorous physical activity (MVPA) suggests children with developmental coordination disorder (DCD) may be susceptible to inactivity-related conditions such as cardiovascular diseases. The aim of this study was to compare children with and without DCD on physical activity patterns, activity…

  13. Online Activity Levels Are Related to Caffeine Dependency.

    PubMed

    Phillips, James G; Landhuis, C Erik; Shepherd, Daniel; Ogeil, Rowan P

    2016-05-01

    Online activity could serve in the future as behavioral markers of emotional states for computer systems (i.e., affective computing). Hence, this study considered relationships between self-reported stimulant use and online study patterns. Sixty-two undergraduate psychology students estimated their daily caffeine use, and this was related to study patterns as tracked by their use of a Learning Management System (Blackboard). Caffeine dependency was associated with less time spent online, lower rates of file access, and fewer online activities completed. Reduced breadth or depth of processing during work/study could be used as a behavioral marker of stimulant use. PMID:27096737

  14. Patterns of presynaptic activity and synaptic strength interact to produce motor output.

    PubMed

    Wright, Terrence Michael; Calabrese, Ronald L

    2011-11-30

    Motor neuron activity is coordinated by premotor networks into a functional motor pattern by complex patterns of synaptic drive. These patterns combine both the temporal pattern of spikes of the premotor network and the profiles of synaptic strengths (i.e., conductances). Given the complexity of premotor networks in vertebrates, it has been difficult to ascertain the relative contributions of temporal patterns and synaptic strength profiles to the motor patterns observed in these animals. Here, we use the leech (Hirudo sp.) heartbeat central pattern generator (CPG), in which we can measure both the temporal pattern and the synaptic strength profiles of the entire premotor network and the motor outflow in individual animals. In this system, a series of motor neurons all receive input from the same premotor interneurons of the CPG but must be coordinated differentially to produce a functional pattern. These properties allow a theoretical and experimental dissection of the rules that govern how temporal patterns and synaptic strength profiles are combined in motor neurons so that functional motor patterns emerge, including an analysis of the impact of animal-to-animal variation in input to such variation in output. In the leech, segmental heart motor neurons are coordinated alternately in a synchronous and peristaltic pattern. We show that synchronous motor patterns result from a nearly synchronous premotor temporal pattern produced by the leech heartbeat CPG. For peristaltic motor patterns, the staggered premotor temporal pattern determines the phase range over which segmental motor neurons can fire while synaptic strength profiles define the intersegmental motor phase progression realized. PMID:22131417

  15. A survey of daily asthmatic activity patterns in Cincinnati

    SciTech Connect

    Not Available

    1992-11-01

    A survey was undertaken in Cincinnati to obtain information on the activity patterns of asthmatics. Because studies have demonstrated symptomatic responses to elevated levels of SO[sub 2] only during outdoor exercise, information on the behavioral patterns of asthmatics is vital for the accurate estimation of risk due to air pollution exposures. In particular, data detailing the actual likelihood of asthmatics being engaged in strenuous outdoor activity at any given time of day is essential for an accurate appraisal of response probability. This, in turn, is necessary for an accurate estimate of risk. In the absence of such activity data, those concerned with the setting of short-term SO[sub 2] regulations are required to use purely subjective judgment to estimate how many asthmatics are engaged in strenuous outdoor exercise when SO[sub 2] levels are high enough to affect them. The activity pattern data give an indication of how much such an assumption would overestimate the true response and thus the true risk associated with SO[sub 2]. Lack of information on the activity patterns of asthmatics has thus been a critical gap in the SO[sub 2] risk assessment process. The primary purpose of this survey was to fill that gap.

  16. Spiral and never-settling patterns in active systems

    NASA Astrophysics Data System (ADS)

    Yang, X.; Marenduzzo, D.; Marchetti, M. C.

    2014-01-01

    We present a combined numerical and analytical study of pattern formation in an active system where particles align, possess a density-dependent motility, and are subject to a logistic reaction. The model can describe suspensions of reproducing bacteria, as well as polymerizing actomyosin gels in vitro or in vivo. In the disordered phase, we find that motility suppression and growth compete to yield stable or blinking patterns, which, when dense enough, acquire internal orientational ordering to give asters or spirals. We predict these may be observed within chemotactic aggregates in bacterial fluids. In the ordered phase, the reaction term leads to previously unobserved never-settling patterns which can provide a simple framework to understand the formation of motile and spiral patterns in intracellular actin systems.

  17. Spiral and never-settling patterns in active systems.

    PubMed

    Yang, X; Marenduzzo, D; Marchetti, M C

    2014-01-01

    We present a combined numerical and analytical study of pattern formation in an active system where particles align, possess a density-dependent motility, and are subject to a logistic reaction. The model can describe suspensions of reproducing bacteria, as well as polymerizing actomyosin gels in vitro or in vivo. In the disordered phase, we find that motility suppression and growth compete to yield stable or blinking patterns, which, when dense enough, acquire internal orientational ordering to give asters or spirals. We predict these may be observed within chemotactic aggregates in bacterial fluids. In the ordered phase, the reaction term leads to previously unobserved never-settling patterns which can provide a simple framework to understand the formation of motile and spiral patterns in intracellular actin systems. PMID:24580261

  18. Age-related changes in serological susceptibility patterns to measles

    PubMed Central

    Xiong, Yongzhen; Wang, Dong; Lin, Weiyan; Tang, Hao; Chen, Shaoli; Ni, Jindong

    2014-01-01

    The present study was performed to determine the seroprevalence of IgG measles antibodies in Dongguan residents (irrespective of vaccination status), to analyze the changes in age-related serological susceptibility patterns. A total of 1960 residents aged 0–60 years and 315 mother–infant pairs were studied. Serum IgG antibodies against measles virus were measured by ELISA. The overall seroprevalence was 93.4% in the general population in Dongguan, China. In subgroups aged 1–29 years who were likely vaccinated, there was a declining trend of seropositivity with age from 98.6% at 1–4 years to 85.7% at 20–29 years (P < 0.0001). Seroprevalence were near or >95% in the older population (30–39 years and ≥40 years) who had not been immunized against measles. Age and sex were independent factors associated with seropositivity. Seroprevalence in pregnant women and their newborns was 87.0% and 84.1%, respectively. Our results suggest that the waning vaccine-induced immunity may be the main cause of increased serological susceptibility in young adults and young infants. An additional vaccination strategy that targets young adults is important for elimination of measles. PMID:24448194

  19. Cerebral Activity Changes in Different Traditional Chinese Medicine Patterns of Psychogenic Erectile Dysfunction Patients

    PubMed Central

    Liu, Qi; Zhang, Peihai; Pan, Junjie; Li, Zhengjie; Liu, Jixin; Li, Guangsen; Qin, Wei; You, Yaodong; Yu, Xujun; Sun, Jinbo; Dong, Minghao; Gong, Qiyong; Guo, Jun; Chang, Degui

    2015-01-01

    Background. Pattern differentiation is the foundation of traditional Chinese medicine (TCM) treatment for erectile dysfunction (ED). This study aims to investigate the differences in cerebral activity in ED patients with different TCM patterns. Methods. 27 psychogenic ED patients and 27 healthy subjects (HS) were enrolled in this study. Each participant underwent an fMRI scan in resting state. The fractional amplitude of low-frequency fluctuation (fALFF) was used to detect the brain activity changes in ED patients with different patterns. Results. Compared to HS, ED patients showed an increased cerebral activity in bilateral cerebellum, insula, globus pallidus, parahippocampal gyrus, orbitofrontal cortex (OFC), and middle cingulate cortex (MCC). Compared to the patients with liver-qi stagnation and spleen deficiency pattern (LSSDP), the patients with kidney-yang deficiency pattern (KDP) showed an increased activity in bilateral brainstem, cerebellum, hippocampus, and the right insula, thalamus, MCC, and a decreased activity in bilateral putamen, medial frontal gyrus, temporal pole, and the right caudate nucleus, OFC, anterior cingulate cortex, and posterior cingulate cortex (P < 0.005). Conclusions. The ED patients with different TCM patterns showed different brain activities. The differences in cerebral activity between LSSDP and KDP were mainly in the emotion-related regions, including prefrontal cortex and cingulated cortex. PMID:26180534

  20. Sequences of cortical activation for tactile pattern discrimination using magnetoencephalography.

    PubMed

    Reed, Catherine L; Hagler, Donald J; Marinkovic, Ksenija; Dale, Anders; Halgren, Eric

    2009-07-01

    To observe sequential stages in tactile pattern discrimination and their modification with and without attention, we used whole-head anatomically constrained magnetoencephalography to spatiotemporally map brain responses. Eight, normal, right-handed participants discriminated between two patterns presented on the palm. Latencies of neural activity were determined from stimulus contact with the palm. Early cortical activation moved from sensorimotor cortex (SM1) to secondary somatosensory cortex (SII), Broca's area (BA), and superior parietal cortex by 65 ms. It continued bilaterally to temporal and frontal poles by 290 ms. Subtraction of nonattended from attended conditions removed primarily the early contralateral sensory components. There was some indication of a preferred order of sensory processing that may express and optimize hemispheric computational specializations. Results indicate similar functional organizations for tactile and visual pattern recognition. PMID:19525880

  1. Retinal waves coordinate patterned activity throughout the developing visual system

    PubMed Central

    Ackman, James B.; Burbridge, Timothy J.; Crair, Michael C.

    2014-01-01

    Summary The morphologic and functional development of the vertebrate nervous system is initially governed by genetic factors and subsequently refined by neuronal activity. However, fundamental features of the nervous system emerge before sensory experience is possible. Thus, activity-dependent development occurring before the onset of experience must be driven by spontaneous activity, but the origin and nature of activity in vivo remains largely untested. Here we use optical methods to demonstrate in live neonatal mice that waves of spontaneous retinal activity are present and propagate throughout the entire visual system before eye opening. This patterned activity encompassed the visual field, relied on cholinergic neurotransmission, preferentially initiated in the binocular retina, and exhibited spatiotemporal correlations between the two hemispheres. Retinal waves were the primary source of activity in the midbrain and primary visual cortex, but only modulated ongoing activity in secondary visual areas. Thus, spontaneous retinal activity is transmitted through the entire visual system and carries patterned information capable of guiding the activity-dependent development of complex intra- and inter- hemispheric circuits before the onset of vision. PMID:23060192

  2. PROCEEDINGS OF THE RESEARCH PLANNING CONFERENCE ON HUMAN ACTIVITY PATTERNS

    EPA Science Inventory

    The study of human activity patterns was initially an area of interest in the field of sociology, but recently it has become important to people investigating the amount and extent of exposure of human populations to hazardous chemicals. This report presents the proceedings of a ...

  3. Physical Activity Patterns among U.S. Adults with Disabilities

    ERIC Educational Resources Information Center

    Chiu, Chung-Yi; An, Ruopeng

    2016-01-01

    Purpose: To characterize physical activity patterns among people with disabilities using data from a nationally representative health survey. Method: Individual-level data came from the Behavioral Risk Factor Surveillance System 2011 survey. Pearson's chi-squared tests were conducted to assess the difference in the proportion distribution of…

  4. Active Commuting Patterns at a Large, Midwestern College Campus

    ERIC Educational Resources Information Center

    Bopp, Melissa; Kaczynski, Andrew; Wittman, Pamela

    2011-01-01

    Objective: To understand patterns and influences on active commuting (AC) behavior. Participants: Students and faculty/staff at a university campus. Methods: In April-May 2008, respondents answered an online survey about mode of travel to campus and influences on commuting decisions. Hierarchical regression analyses predicted variance in walking…

  5. Muscle activation patterns in patients with recurrent shoulder instability

    PubMed Central

    Jaggi, Anju; Noorani, Ali; Malone, Alex; Cowan, Joseph; Lambert, Simon; Bayley, Ian

    2012-01-01

    Purpose: The aim of this study is to present muscle patterns observed with the direction of instability in a series of patients presenting with recurrent shoulder instability. Materials and Methods: A retrospective review was carried out on shoulder instability cases referred for fine wire dynamic electromyography (DEMG) studies at a specialist upper limb centre between 1981 and 2003. An experienced consultant clinical neurophysiologist performed dual needle insertion into four muscles (pectoralis major (PM), latissimus dorsi (LD), anterior deltoid (AD) and infraspinatus (IS)) in shoulders that were suspected to have increased or suppressed activation of muscles that could be contributing to the instability. Raw EMG signals were obtained while subjects performed simple uniplanar movements of the shoulder. The presence or absence of muscle activation was noted and compared to clinical diagnosis and direction of instability. Results: A total of 140 (26.6%) shoulders were referred for fine wire EMG, and 131 studies were completed. Of the shoulders tested, 122 shoulders (93%) were identified as having abnormal patterns and nine had normal patterns. PM was found to be more active in 60% of shoulders presenting with anterior instability. LD was found to be more active in 81% of shoulders with anterior instability and 80% with posterior instability. AD was found to be more active in 22% of shoulders with anterior instability and 18% with posterior instability. IS was found to be inappropriately inactive in only 3% of shoulders with anterior instability but in 25% with posterior instability. Clinical assessment identified 93% of cases suspected to have muscle patterning, but the specificity of the clinical assessment was only correct in 11% of cases. Conclusion: The DEMG results suggest that increased activation of LD may play a role in both anterior and posterior shoulder instability; increased activation of PM may play a role in anterior instability. PMID:23493512

  6. Leisure activity patterns and their associations with overweight: a prospective study among adolescents.

    PubMed

    Lajunen, Hanna-Reetta; Keski-Rahkonen, Anna; Pulkkinen, Lea; Rose, Richard J; Rissanen, Aila; Kaprio, Jaakko

    2009-10-01

    We examined longitudinal associations between individual leisure activities (television viewing, video viewing, computer games, listening to music, board games, musical instrument playing, reading, arts, crafts, socializing, clubs or scouts, sports, outdoor activities) and being overweight using logistic regression and latent class analysis in a cohort of Finnish twins responding to self-report questionnaires at 11-12 (N=5184), 14, and 17 years. We also studied activity patterns ("Active and sociable", "Active but less sociable", "Passive but sociable", "Passive and solitary") thought to represent different lifestyles. Among boys, activity patterns did not predict becoming overweight, but sports and playing an instrument reduced the risk and arts and listening to music increased it. Among girls, few individual leisure activities predicted becoming overweight. However, girls in the "Passive and solitary" cluster carried the greatest risk of becoming overweight in late adolescence. Studying leisure activities related to overweight may help focus specific interventions on high risk groups. PMID:19345989

  7. A Computational Model of Dynein Activation Patterns that Can Explain Nodal Cilia Rotation

    PubMed Central

    Chen, Duanduan; Zhong, Yi

    2015-01-01

    Normal left-right patterning in vertebrates depends on the rotational movement of nodal cilia. In order to produce this ciliary motion, the activity of axonemal dyneins must be tightly regulated in a temporal and spatial manner; the specific activation pattern of the dynein motors in the nodal cilia has not been reported. Contemporary imaging techniques cannot directly assess dynein activity in a living cilium. In this study, we establish a three-dimensional model to mimic the ciliary ultrastructure and assume that the activation of dynein proteins is related to the interdoublet distance. By employing finite-element analysis and grid deformation techniques, we simulate the mechanical function of dyneins by pairs of point loads, investigate the time-variant interdoublet distance, and simulate the dynein-triggered ciliary motion. The computational results indicate that, to produce the rotational movement of nodal cilia, the dynein activity is transferred clockwise (looking from the tip) between the nine doublet microtubules, and along each microtubule, the dynein activation should occur faster at the basal region and slower when it is close to the ciliary tip. Moreover, the time cost by all the dyneins along one microtubule to be activated can be used to deduce the dynein activation pattern; it implies that, as an alternative method, measuring this time can indirectly reveal the dynein activity. The proposed protein-structure model can simulate the ciliary motion triggered by various dynein activation patterns explicitly and may contribute to furthering the studies on axonemal dynein activity. PMID:26153700

  8. WETRAX: WEather Patterns, Cyclone TRAcks and related precipitation EXtremes

    NASA Astrophysics Data System (ADS)

    Hofstätter, Michael; Beck, Christoph; Chimani, Barbara; Ganekind, Manfred; Homan, Markus; Jacobeit, Jucundus; Phillip, Andreas

    2013-04-01

    Excessive large scale (LS) precipitation entails high risk of related flooding and is therefore of particular significance for subsequent infrastructural damage, financial loss or the direct threat of human life. The potential and importance of certain atmospheric cyclone tracks or circulation types for such precipitation events, is well known in the hydro-meteorological community, not least because of the flood events in August 2005 and August 2002 for example. However many important questions remain unanswered in this issue. For example, not enough findings are on hand assessing the relevance of certain circulation types or cyclone track types for large scale precipitation characteristics in Central Europe. In particular changes in the risk of LS extreme precipitation under future climate change conditions due to an altered atmospheric circulation, remain unknown in fact. In this collaborative study repetitive atmospheric patterns as large-scale circulation types and cyclone track types are investigated in terms of their relevance for non-convective extreme precipitation over Southern Germany and Austria. Two different Global Climate Models will be evaluated in their ability to simulate the important atmospheric characteristics under current climate conditions, in order to assess the changing probability of occurrence of extreme precipitation events under future climate conditions. The results of this study will give new insights in the nature of atmospheric cyclones and circulation types as the trigger of large scale precipitation in the study region, hence improving hydro-meteorological knowledge and providing basic essentials for the trans-national water resource management under the aspect of ongoing climate change.

  9. Virtual Active Touch Using Randomly Patterned Intracortical Microstimulation

    PubMed Central

    O’Doherty, Joseph E.; Lebedev, Mikhail A.; Li, Zheng; Nicolelis, Miguel A.L.

    2012-01-01

    Intracortical microstimulation (ICMS) has promise as a means for delivering somatosensory feedback in neuroprosthetic systems. Various tactile sensations could be encoded by temporal, spatial, or spatiotemporal patterns of ICMS. However, the applicability of temporal patterns of ICMS to artificial tactile sensation during active exploration is unknown, as is the minimum discriminable difference between temporally modulated ICMS patterns. We trained rhesus monkeys in an active exploration task in which they discriminated periodic pulse-trains of ICMS (200 Hz bursts at a 10 Hz secondary frequency) from pulse trains with the same average pulse rate, but distorted periodicity (200 Hz bursts at a variable instantaneous secondary frequency). The statistics of the aperiodic pulse trains were drawn from a gamma distribution with mean inter-burst intervals equal to those of the periodic pulse trains. The monkeys distinguished periodic pulse trains from aperiodic pulse trains with coefficients of variation 0.25 or greater. Reconstruction of movement kinematics, extracted from the activity of neuronal populations recorded in the sensorimotor cortex concurrent with the delivery of ICMS feedback, improved when the recording intervals affected by ICMS artifacts were removed from analysis. These results add to the growing evidence that temporally patterned ICMS can be used to simulate a tactile sense for neuroprosthetic devices. PMID:22207642

  10. Active Curved Polymers Form Vortex Patterns on Membranes

    NASA Astrophysics Data System (ADS)

    Denk, Jonas; Huber, Lorenz; Reithmann, Emanuel; Frey, Erwin

    2016-04-01

    Recent in vitro experiments with FtsZ polymers show self-organization into different dynamic patterns, including structures reminiscent of the bacterial Z ring. We model FtsZ polymers as active particles moving along chiral, circular paths by Brownian dynamics simulations and a Boltzmann approach. Our two conceptually different methods point to a generic phase behavior. At intermediate particle densities, we find self-organization into vortex structures including closed rings. Moreover, we show that the dynamics at the onset of pattern formation is described by a generalized complex Ginzburg-Landau equation.

  11. Active Curved Polymers Form Vortex Patterns on Membranes.

    PubMed

    Denk, Jonas; Huber, Lorenz; Reithmann, Emanuel; Frey, Erwin

    2016-04-29

    Recent in vitro experiments with FtsZ polymers show self-organization into different dynamic patterns, including structures reminiscent of the bacterial Z ring. We model FtsZ polymers as active particles moving along chiral, circular paths by Brownian dynamics simulations and a Boltzmann approach. Our two conceptually different methods point to a generic phase behavior. At intermediate particle densities, we find self-organization into vortex structures including closed rings. Moreover, we show that the dynamics at the onset of pattern formation is described by a generalized complex Ginzburg-Landau equation. PMID:27176542

  12. Blast-related fracture patterns: a forensic biomechanical approach

    PubMed Central

    Ramasamy, Arul; Hill, Adam M.; Masouros, Spyros; Gibb, Iain; Bull, Anthony M. J.; Clasper, Jon C.

    2011-01-01

    Improved protective measures and medical care has increased the survivability from battlefield injuries. In an attempt to reduce the debilitating consequences of blast injury, understanding and mitigating the effects of explosion on the extremities is key. In this study, forensic biomechanical analyses have been applied to determine mechanisms of injury after the traumatic event. The aims of this study were (i) to determine which effects of the explosion are responsible for combat casualty extremity bone injury in two distinct environments, namely open, free-field (open group), and in vehicle or in cover (enclosed group), and (ii) to determine whether patterns of combat casualty bone injury differed between environments. Medical records of casualties admitted to a military hospital in Afghanistan were reviewed over a six-month period. Explosive injuries have been sub-divided traditionally into primary, secondary and tertiary effects. All radiographs were independently reviewed by a military radiologist, a team of military orthopaedic surgeons and a team of academic biomechanists, in order to determine ‘zones of injury’ (ZoIs), and their related mechanisms. Sixty-two combat casualties with 115 ZoIs were identified. Thirty-four casualties in the open group sustained 56 ZoIs; 28 casualties in the enclosed group sustained 59 ZoIs. There was no statistical difference in mean ZoIs per casualty between groups (p = 0.54). There was a higher proportion of lower limb injuries in the enclosed group compared with the open group (p < 0.05). Of the casualties in the open group, 1 ZoI was owing to the primary effects of blast, 10 owing to a combination of primary and secondary blast effects, 23 owing to secondary blast effects and 24 owing to tertiary blast effects. In contrast, tertiary blast effects predominated in the enclosed group, accounting for 96 per cent of ZoIs. These data clearly demonstrate two distinct injury groups based upon the casualties' environment. The

  13. Two different interictal spike patterns anticipate ictal activity in vitro

    PubMed Central

    Avoli, Massimo; Panuccio, Gabriella; Herrington, Rochelle; D’Antuono, Margherita; de Guzman, Philip; Lévesque, Maxime

    2016-01-01

    4-Aminopyridine (4AP, 50 μM) induces interictal- and ictal-like discharges in brain slices including parahippocampal areas such as the entorhinal cortex (EC) but the relation between these two types of epileptiform activity remains undifined. Here, by employing field potential recordings in rat EC slices during 4AP application, we found that: (i) interictal events have a wide range of duration (0.4–3.3 s) and interval of occurrence (1.4–84 s); (ii) ictal discharges are either preceded by an isolated “slow” interictal discharge (ISID; duration=1.5±0.1 s, interval of occurrence=33.8±1.8 s) or suddenly initiate from a pattern of frequent polispike interictal discharge (FPID; duration=0.8±0.1 s; interval of occurrence=2.7±0.2 s); and (iii) ISID-triggered ictal events have longer duration (116±7.3 s) and interval of occurrence (425.8±42.3 s) than those initiating suddenly during FPID (58.3±7.8 s and 202.1±21.8 s, respectively). Glutamatergic receptor antagonists abolished ictal discharges in all experiments, markedly reduced FPIDs but did not influence ISIDs. We also discovered that high-frequency oscillations (HFOs, 80–500 Hz) occur more frequently during ISIDs as compared to FPIDs, and mainly coincide with the onset of ISID-triggered ictal discharges. These findings indicate that interictal events may define ictal onset features resembling those seen in vivo in low-voltage fast activity onset seizures. We propose a similar condition to occur in vivo in temporal lobe epileptic patients and animal models. PMID:23270790

  14. Active gels: dynamics of patterning and self-organization

    NASA Astrophysics Data System (ADS)

    Backouche, F.; Haviv, L.; Groswasser, D.; Bernheim-Groswasser, A.

    2006-12-01

    The actin cytoskeleton is an active gel which constantly remodels during cellular processes such as motility and division. Myosin II molecular motors are involved in this active remodeling process and therefore control the dynamic self-organization of cytoskeletal structures. Due to the complexity of in vivo systems, it is hard to investigate the role of myosin II in the reorganization process which determines the resulting cytoskeletal structures. Here we use an in vitro model system to show that myosin II actively reorganizes actin into a variety of mesoscopic patterns, but only in the presence of bundling proteins. We find that the nature of the reorganization process is complex, exhibiting patterns and dynamical phenomena not predicted by current theoretical models and not observed in corresponding passive systems (excluding motors). This system generates active networks, asters and even rings depending on motor and bundling protein concentrations. Furthermore, the motors generate the formation of the patterns, but above a critical concentration they can also disassemble them and even totally prevent the polymerization and bundling of actin filaments. These results may suggest that tuning the assembly and disassembly of cytoskeletal structures can be obtained by tuning the local myosin II concentration/activity.

  15. Factors Associated with Evaluating Public Relations Activities.

    ERIC Educational Resources Information Center

    McElreath, Mark P.

    More than 150 public relations practitioners responded to a survey designed to identify and clarify factors associated with evaluative research in public relations. Responses indicated that (1) no more than half the practitioners formally evaluate their public relations activities on a regular basis; (2) the majority of evaluation is done…

  16. Optimizing human activity patterns using global sensitivity analysis

    PubMed Central

    Hickmann, Kyle S.; Mniszewski, Susan M.; Del Valle, Sara Y.; Hyman, James M.

    2014-01-01

    Implementing realistic activity patterns for a population is crucial for modeling, for example, disease spread, supply and demand, and disaster response. Using the dynamic activity simulation engine, DASim, we generate schedules for a population that capture regular (e.g., working, eating, and sleeping) and irregular activities (e.g., shopping or going to the doctor). We use the sample entropy (SampEn) statistic to quantify a schedule’s regularity for a population. We show how to tune an activity’s regularity by adjusting SampEn, thereby making it possible to realistically design activities when creating a schedule. The tuning process sets up a computationally intractable high-dimensional optimization problem. To reduce the computational demand, we use Bayesian Gaussian process regression to compute global sensitivity indices and identify the parameters that have the greatest effect on the variance of SampEn. We use the harmony search (HS) global optimization algorithm to locate global optima. Our results show that HS combined with global sensitivity analysis can efficiently tune the SampEn statistic with few search iterations. We demonstrate how global sensitivity analysis can guide statistical emulation and global optimization algorithms to efficiently tune activities and generate realistic activity patterns. Though our tuning methods are applied to dynamic activity schedule generation, they are general and represent a significant step in the direction of automated tuning and optimization of high-dimensional computer simulations. PMID:25580080

  17. Optimizing human activity patterns using global sensitivity analysis

    SciTech Connect

    Fairchild, Geoffrey; Hickmann, Kyle S.; Mniszewski, Susan M.; Del Valle, Sara Y.; Hyman, James M.

    2013-12-10

    Implementing realistic activity patterns for a population is crucial for modeling, for example, disease spread, supply and demand, and disaster response. Using the dynamic activity simulation engine, DASim, we generate schedules for a population that capture regular (e.g., working, eating, and sleeping) and irregular activities (e.g., shopping or going to the doctor). We use the sample entropy (SampEn) statistic to quantify a schedule’s regularity for a population. We show how to tune an activity’s regularity by adjusting SampEn, thereby making it possible to realistically design activities when creating a schedule. The tuning process sets up a computationally intractable high-dimensional optimization problem. To reduce the computational demand, we use Bayesian Gaussian process regression to compute global sensitivity indices and identify the parameters that have the greatest effect on the variance of SampEn. Here we use the harmony search (HS) global optimization algorithm to locate global optima. Our results show that HS combined with global sensitivity analysis can efficiently tune the SampEn statistic with few search iterations. We demonstrate how global sensitivity analysis can guide statistical emulation and global optimization algorithms to efficiently tune activities and generate realistic activity patterns. Finally, though our tuning methods are applied to dynamic activity schedule generation, they are general and represent a significant step in the direction of automated tuning and optimization of high-dimensional computer simulations.

  18. Optimizing human activity patterns using global sensitivity analysis

    DOE PAGESBeta

    Fairchild, Geoffrey; Hickmann, Kyle S.; Mniszewski, Susan M.; Del Valle, Sara Y.; Hyman, James M.

    2013-12-10

    Implementing realistic activity patterns for a population is crucial for modeling, for example, disease spread, supply and demand, and disaster response. Using the dynamic activity simulation engine, DASim, we generate schedules for a population that capture regular (e.g., working, eating, and sleeping) and irregular activities (e.g., shopping or going to the doctor). We use the sample entropy (SampEn) statistic to quantify a schedule’s regularity for a population. We show how to tune an activity’s regularity by adjusting SampEn, thereby making it possible to realistically design activities when creating a schedule. The tuning process sets up a computationally intractable high-dimensional optimizationmore » problem. To reduce the computational demand, we use Bayesian Gaussian process regression to compute global sensitivity indices and identify the parameters that have the greatest effect on the variance of SampEn. Here we use the harmony search (HS) global optimization algorithm to locate global optima. Our results show that HS combined with global sensitivity analysis can efficiently tune the SampEn statistic with few search iterations. We demonstrate how global sensitivity analysis can guide statistical emulation and global optimization algorithms to efficiently tune activities and generate realistic activity patterns. Finally, though our tuning methods are applied to dynamic activity schedule generation, they are general and represent a significant step in the direction of automated tuning and optimization of high-dimensional computer simulations.« less

  19. Age-Related Changes in Strength, Joint Laxity, and Walking Patterns: Are They Related to Knee Osteoarthritis?

    PubMed Central

    Rudolph, Katherine S; Schmitt, Laura C; Lewek, Michael D

    2008-01-01

    Background and Purpose Aging is associated with musculoskeletal changes and altered walking patterns. These changes are common in people with knee osteoarthritis (OA) and may precipitate the development of OA. We examined age-related changes in musculoskeletal structures and walking patterns to better understand the relationship between aging and knee OA. Methods Forty-four individuals without OA (15 younger, 15 middle-aged, 14 older adults) and 15 individuals with medial knee OA participated. Knee laxity, quadriceps femoris muscle strength (force-generating capacity), and gait were assessed. Results Medial laxity was greater in the OA group, but there were no differences between the middle-aged and older control groups. Quadriceps femoris strength was less in the older control group and in the OA group. During the stance phase of walking, the OA group demonstrated less knee flexion and greater knee adduction, but there were no differences in knee motion among the control groups. During walking, the older control group exhibited greater quadriceps femoris muscle activity and the OA group used greater muscle co-contraction. Discussion and Conclusion Although weaker, the older control group did not use truncated motion or higher co-contraction. The maintenance of movement patterns that were similar to the subjects in the young control group may have helped to prevent development of knee OA. Further investigation is warranted regarding age-related musculoskeletal changes and their influence on the development of knee OA. PMID:17785376

  20. Turing pattern dynamics in an activator-inhibitor system with superdiffusion

    NASA Astrophysics Data System (ADS)

    Zhang, Lai; Tian, Canrong

    2014-12-01

    The fractional operator is introduced to an activator-inhibitor system to describe species anomalous superdiffusion. The effects of the superdiffusive exponent on pattern formation and pattern selection are studied. Our linear stability analysis shows that the wave number of the Turing pattern increases with the superdiffusive exponent. A weakly nonlinear analysis yields a system of amplitude equations and the analysis of these amplitude equations predicts parameter regimes where hexagons, stripes, and their coexistence are expected. Numerical simulations of the activator-inhibitor model near the stability boundaries confirm our analytical results. Since diffusion rate manifests in both diffusion constant and diffusion exponent, we numerically explore their interactions on the emergence of Turing patterns. When the activator and inhibitor have different superdiffusive exponents, we find that the critical ratio of the diffusion rate of the inhibitor to the activator, required for the formation of the Turing pattern, increases monotonically with the superdiffusive exponent. We conclude that small ratio (than unity) of anomalous diffusion exponent between the inhibitor and activator is more likely to promote the emergence of the Turing pattern, relative to the normal diffusion.

  1. Orbitofrontal sulcogyral patterns are related to temperamental risk for psychopathology

    PubMed Central

    Whittle, Sarah; Bartholomeusz, Cali; Yücel, Murat; Dennison, Meg; Vijayakumar, Nandita

    2014-01-01

    There are marked individual differences in the pattern of cortical (sulcogyral) folding in the orbitofrontal cortex (OFC), and there is a growing literature suggesting that these individual differences are associated with risk for psychotic disorders. To date, however, no study has investigated whether OFC folding patterns are associated with broader risk factors relevant to a range of psychopathology. This study helps address this knowledge gap by examining whether OFC sulcogyral folding patterns are associated with putative risk factors, specifically affective temperament and psychiatric symptoms, in a large community sample (N = 152) of adolescents. Results showed that the most common pattern of folding (‘Type I’, marked by discontinuity of the medial orbital sulcus and continuity of the lateral orbital sulcus) was associated with low levels of Surgency, high levels of Negative Affectivity (in girls) and higher depressive symptoms. This pattern was also associated with reduced thickness of OFC gray matter. Overall, the findings, combined with previous work, suggest some specificity of neurodevelopmental risk for different types of psychopathology. Thus, these results have the potential to inform the early identification of at-risk individuals. PMID:23160816

  2. Unraveling dynamics of human physical activity patterns in chronic pain conditions

    NASA Astrophysics Data System (ADS)

    Paraschiv-Ionescu, Anisoara; Buchser, Eric; Aminian, Kamiar

    2013-06-01

    Chronic pain is a complex disabling experience that negatively affects the cognitive, affective and physical functions as well as behavior. Although the interaction between chronic pain and physical functioning is a well-accepted paradigm in clinical research, the understanding of how pain affects individuals' daily life behavior remains a challenging task. Here we develop a methodological framework allowing to objectively document disruptive pain related interferences on real-life physical activity. The results reveal that meaningful information is contained in the temporal dynamics of activity patterns and an analytical model based on the theory of bivariate point processes can be used to describe physical activity behavior. The model parameters capture the dynamic interdependence between periods and events and determine a `signature' of activity pattern. The study is likely to contribute to the clinical understanding of complex pain/disease-related behaviors and establish a unified mathematical framework to quantify the complex dynamics of various human activities.

  3. Mesoscopic Patterns of Neural Activity Support Songbird Cortical Sequences

    PubMed Central

    Guitchounts, Grigori; Velho, Tarciso; Lois, Carlos; Gardner, Timothy J.

    2015-01-01

    Time-locked sequences of neural activity can be found throughout the vertebrate forebrain in various species and behavioral contexts. From “time cells” in the hippocampus of rodents to cortical activity controlling movement, temporal sequence generation is integral to many forms of learned behavior. However, the mechanisms underlying sequence generation are not well known. Here, we describe a spatial and temporal organization of the songbird premotor cortical microcircuit that supports sparse sequences of neural activity. Multi-channel electrophysiology and calcium imaging reveal that neural activity in premotor cortex is correlated with a length scale of 100 µm. Within this length scale, basal-ganglia–projecting excitatory neurons, on average, fire at a specific phase of a local 30 Hz network rhythm. These results show that premotor cortical activity is inhomogeneous in time and space, and that a mesoscopic dynamical pattern underlies the generation of the neural sequences controlling song. PMID:26039895

  4. Mesoscopic patterns of neural activity support songbird cortical sequences.

    PubMed

    Markowitz, Jeffrey E; Liberti, William A; Guitchounts, Grigori; Velho, Tarciso; Lois, Carlos; Gardner, Timothy J

    2015-06-01

    Time-locked sequences of neural activity can be found throughout the vertebrate forebrain in various species and behavioral contexts. From "time cells" in the hippocampus of rodents to cortical activity controlling movement, temporal sequence generation is integral to many forms of learned behavior. However, the mechanisms underlying sequence generation are not well known. Here, we describe a spatial and temporal organization of the songbird premotor cortical microcircuit that supports sparse sequences of neural activity. Multi-channel electrophysiology and calcium imaging reveal that neural activity in premotor cortex is correlated with a length scale of 100 µm. Within this length scale, basal-ganglia-projecting excitatory neurons, on average, fire at a specific phase of a local 30 Hz network rhythm. These results show that premotor cortical activity is inhomogeneous in time and space, and that a mesoscopic dynamical pattern underlies the generation of the neural sequences controlling song. PMID:26039895

  5. Reliable and Affordable Control Systems Active Combustor Pattern Factor Control

    NASA Technical Reports Server (NTRS)

    McCarty, Bob; Tomondi, Chris; McGinley, Ray

    2004-01-01

    Active, closed-loop control of combustor pattern factor is a cooperative effort between Honeywell (formerly AlliedSignal) Engines and Systems and the NASA Glenn Research Center to reduce emissions and turbine-stator vane temperature variations, thereby enhancing engine performance and life, and reducing direct operating costs. Total fuel flow supplied to the engine is established by the speed/power control, but the distribution to individual atomizers will be controlled by the Active Combustor Pattern Factor Control (ACPFC). This system consist of three major components: multiple, thin-film sensors located on the turbine-stator vanes; fuel-flow modulators for individual atomizers; and control logic and algorithms within the electronic control.

  6. Adolescent Patterns of Communication about Sexually Related Topics.

    ERIC Educational Resources Information Center

    Tucker, Sandra K.

    1989-01-01

    Examined familial patterns in amounts of information received about menstrual cycle, sex, and contraception among Black adolescent daughters, mothers, and grandmothers (N=179) representing 53 family units. Results indicated that mothers were most likely to be source of information. Found much information necessary for sexual health and informed…

  7. Interplay activity-connectivity: Dynamics in patterned neuronal cultures

    NASA Astrophysics Data System (ADS)

    Tibau, E.; Bendiksen, Ch.; Teller, S.; Amigó, N.; Soriano, J.

    2013-01-01

    The ability of a neuronal tissue to efficiently process and transmit information depends on both the intrinsic dynamical properties of the neurons and the connectivity between them. One of the few experimental systems where one can vary the connectivity of a neuronal network in a control manner are neuronal cultures. Here we show that, by combining neuronal cultures with different pattering techniques, we can control and dictate the connectivity of neuronal networks. The emerging cultures are characterized by a rich spontaneous activity, but with some dynamical traits that can be ascribed to the underlying, engineered wiring architecture. Simple patterned cultures can be obtained by plating neurons onto predefined topographical molds, which guide neurons and connections through complex paths. In contrast to homogeneous cultures, characterized by an on/off behavior where all neurons fire in a short time window, patterned cultures show more complex spatio-temporal dynamics, and with varying propagation paths and velocities. Patterned cultures provide a valuable tool to understand not only the interplay activity-connectivity, but also aspects such as the emergence and maintenance of spontaneous activity, synchronization, or the presence of specific dynamic motifs.

  8. Implications of climatic seasonality on activity patterns and resource use by sympatric peccaries in northern Pantanal

    NASA Astrophysics Data System (ADS)

    Hofmann, Gabriel Selbach; Coelho, Igor Pfeifer; Bastazini, Vinicius Augusto Galvão; Cordeiro, José Luís Passos; de Oliveira, Luiz Flamarion Barbosa

    2016-03-01

    We evaluated the effects of climate seasonality from a thermal and water availability perspective on the activity patterns and resource use of Pecari tajacu and Tayassu pecari during wet and dry seasons in the northeastern Brazilian Pantanal. We used camera traps and temperature sensors to record species activity patterns in relation to temperature, established five habitat categories based on flooding intensity and local vegetation characteristics, assessed the activity patterns of each species in dry and wet periods and in artificial water bodies using circular statistical metrics, and calculated niche amplitude and overlap on three axes (temperature, time, and habitat) in both periods. Peccaries shared a strong resemblance in resource use and in their responses to seasonal variations in the tested gradients. The activity patterns of both species exhibited a significant correlation with air temperature on all the evaluated measures, and both species strongly reduced their activity when the air temperature exceeded 35 °C. High temperatures associated with low water availability were most likely responsible for the changes in species activity patterns, which resulted in an increased temporal overlap in habitat use throughout the dry season. However, the peccaries avoided intensively flooded habitats; therefore, the habitat gradient overlap was greater during the wet period. Our results show that an increase in niche overlap on the environmental gradient as a result of climatic seasonality may be partially compensated by a reduction in other niche dimensions. In this case, temporal partitioning appears to be an important, viable mechanism to reduce competition by potentially competing species.

  9. Uncovering patterns of forearm muscle activity using multi-channel mechanomyography.

    PubMed

    Alves, Natasha; Chau, Tom

    2010-10-01

    A coordinated activation of distal forearm muscles allows the hand and fingers to be shaped during movement and grasp. However, little is known about how the muscle activation patterns are reflected in multi-channel mechanomyogram (MMG) signals. The purpose of this study is to determine if multi-site MMG signals exhibit distinctive patterns of forearm muscle activity. MMG signals were recorded from forearm muscle sites of nine able-bodied participants during hand movement. By using 14 features selected by a genetic algorithm and classified by a linear discriminant analysis classifier (LDA), we show that MMG patterns are specific and consistent enough to identify 7+/-1 hand movements with an accuracy of 90+/-4%. MMG-based movement recognition required a minimum of three recording sites. Further, by classifying five classes of contraction patterns with 98+/-3% accuracy from MMG signals recorded from the residual limb of an amputee participant, we demonstrate that MMG shows pattern-specificity even in the absence of typical musculature. Multi-site monitoring of the RMS of MMG signals is suggested as a method of estimating the relative contributions of muscles to motor tasks. The patterns in MMG facilitate our understanding of the mechanical activity of muscles during movement. PMID:19854064

  10. Sensory Patterns, Obesity, and Physical Activity Participation of Children With Autism Spectrum Disorder.

    PubMed

    Lawson, Lisa Mische; Foster, Lauren

    2016-01-01

    Obesity is a public health concern for the population in general and for children with autism spectrum disorder (ASD) specifically. The purpose of this study was to understand relationships between sensory patterns, obesity, and physical activity engagement of children with ASD (N = 77) sampled from a specialized community-based swimming program. This retrospective correlational study analyzed program data. Results show that almost half (42.2%) of the children were overweight or obese, and sensory avoiding behaviors were related to higher body mass index (BMI). Children participated in few formal and informal physically active recreation activities. Sensory seeking behaviors were associated with increased participation in informal activities, and higher BMI was associated with less participation in both formal and informal activities. Practitioners should consider sensory processing patterns and BMI when developing community-based programs to promote physical activity of children with ASD. PMID:27548863

  11. Great apes and children infer causal relations from patterns of variation and covariation.

    PubMed

    Völter, Christoph J; Sentís, Inés; Call, Josep

    2016-10-01

    We investigated whether nonhuman great apes (N=23), 2.5-year-old (N=20), and 3-year-old children (N=40) infer causal relations from patterns of variation and covariation by adapting the blicket detector paradigm for apes. We presented chimpanzees (Pan troglodytes), bonobos (Pan paniscus), orangutans (Pongo abelii), gorillas (Gorilla gorilla), and children (Homo sapiens) with a novel reward dispenser, the blicket detector. The detector was activated by inserting specific (yet randomly determined) objects, the so-called blickets. Once activated a reward was released, accompanied by lights and a short tone. Participants were shown different patterns of variation and covariation between two different objects and the activation of the detector. When subsequently choosing between one of the two objects to activate the detector on their own all species, except gorillas (who failed the training), took these patterns of correlation into account. In particular, apes and 2.5-year-old children ignored objects whose effect on the detector completely depended on the presence of another object. Follow-up experiments explored whether the apes and children were also able to re-evaluate evidence retrospectively. Only children (3-year-olds in particular) were able to make such retrospective inferences about causal structures from observing the effects of the experimenter's actions. Apes succeeded here only when they observed the effects of their own interventions. Together, this study provides evidence that apes, like young children, accurately infer causal structures from patterns of (co)variation and that they use this information to inform their own interventions. PMID:27343481

  12. Temporal Links in Daily Activity Patterns between Coral Reef Predators and Their Prey

    PubMed Central

    Bosiger, Yoland J.; McCormick, Mark I.

    2014-01-01

    Few studies have documented the activity patterns of both predators and their common prey over 24 h diel cycles. This study documents the temporal periodicity of two common resident predators of juvenile reef fishes, Cephalopholis cyanostigma (rockcod) and Pseudochromis fuscus (dottyback) and compares these to the activity and foraging pattern of a common prey species, juvenile Pomacentrus moluccensis (lemon damselfish). Detailed observations of activity in the field and using 24 h infrared video in the laboratory revealed that the two predators had very different activity patterns. C. cyanostigma was active over the whole 24 h period, with a peak in feeding strikes at dusk and increased activity at both dawn and dusk, while P. fuscus was not active at night and had its highest strike rates at midday. The activity and foraging pattern of P. moluccensis directly opposes that of C. cyanostigma with individuals reducing strike rate and intraspecific aggression at both dawn and dusk, and reducing distance from shelter and boldness at dusk only. Juveniles examined were just outside the size-selection window of P. fuscus. We suggest that the relatively predictable diel behaviour of coral reef predators results from physiological factors such as visual sensory abilities, circadian rhythmicity, variation in hunting profitability, and predation risk at different times of the day. Our study suggests that the diel periodicity of P. moluccensis behaviour may represent a response to increased predation risk at times when both the ability to efficiently capture food and visually detect predators is reduced. PMID:25354096

  13. State Court Law-Related Education Activities.

    ERIC Educational Resources Information Center

    American Bar Association, Chicago, IL. Special Committee on Youth Education for Citizenship.

    This document lists the law-related education activities conducted by state courts. The listings are arranged by state. Entries list the name of the court, a list of activities provided, descriptions of unusual programs, guidelines for programs that some of the courts have developed, and the name, title or committee, address, and phone number of a…

  14. Retrieving Binary Answers Using Whole-Brain Activity Pattern Classification

    PubMed Central

    Nawa, Norberto E.; Ando, Hiroshi

    2015-01-01

    Multivariate pattern analysis (MVPA) has been successfully employed to advance our understanding of where and how information regarding different mental states is represented in the human brain, bringing new insights into how these states come to fruition, and providing a promising complement to the mass-univariate approach. Here, we employed MVPA to classify whole-brain activity patterns occurring in single fMRI scans, in order to retrieve binary answers from experiment participants. Five healthy volunteers performed two types of mental task while in the MRI scanner: counting down numbers and recalling positive autobiographical events. Data from these runs were used to train individual machine learning based classifiers that predicted which mental task was being performed based on the voxel-based brain activity patterns. On a different day, the same volunteers reentered the scanner and listened to six statements (e.g., “the month you were born is an odd number”), and were told to countdown numbers if the statement was true (yes) or recall positive events otherwise (no). The previously trained classifiers were then used to assign labels (yes/no) to the scans collected during the 24-second response periods following each one of the statements. Mean classification accuracies at the single scan level were in the range of 73.6 to 80.8%, significantly above chance for all participants. When applying a majority vote on the scans within each response period, i.e., the most frequent label (yes/no) in the response period becomes the answer to the previous statement, 5.0 to 5.8 sentences, out of 6, were correctly classified in each one of the runs, on average. These results indicate that binary answers can be retrieved from whole-brain activity patterns, suggesting that MVPA provides an alternative way to establish basic communication with unresponsive patients when other techniques are not successful. PMID:26778992

  15. Causality principles in solar activity -climate relations.

    NASA Astrophysics Data System (ADS)

    Stauning, Peter

    The relations between solar activity and the terrestrial climate have quite often been inves-tigated. In most cases the analyses have been based on comparisons between time series of solar activity parameters, for instance sunspot numbers, and terrestrial climate parameters, for instance global temperatures. However, many of the reported close relations are based on skilfully manipulated data and neglect of basic causality principles. For cause-effect relations to be reliably established, the variations in the causative function must obviously happen prior to the related effects. Thus it is problematic to use, for instance, running averages of parameters, if the result depends too much on posterior elements of the causative time series or precursory elements of the effects. Even more neglected are the causality principles for cause-effect rela-tions with a strongly varying source function, like for instance the 11 year solar activity cycle. In such cases damping of source variations by smoothing data series, introduces additional im-plied delays, which should be considered in the judgement of apparent correlations between the processed time series of cause and effect parameters. The presentation shall illustrate causal-ity relations between solar activity and terrestrial climate parameters and discuss examples of frequently quoted solar activity-climate relations, which violate basic causality principles.

  16. Patterns of adolescent physical activity and dietary behaviours

    PubMed Central

    Pearson, Natalie; Atkin, Andrew J; Biddle, Stuart JH; Gorely, Trish; Edwardson, Charlotte

    2009-01-01

    Background The potential synergistic effects of multiple dietary and physical activity behaviours on the risk of chronic conditions and health outcomes is a key issue for public health. This study examined the prevalence and clustering patterns of multiple health behaviours among a sample of adolescents in the UK. Methods Cross-sectional survey of 176 adolescents aged 12–16 years (49% boys). Adolescents wore accelerometers for seven days and completed a questionnaire assessing fruit, vegetable, and breakfast consumption. The prevalence of adolescents meeting the physical activity (≥ 60 minutes moderate-to-vigorous physical activity/day), fruit and vegetable (≥ 5 portions of FV per day) and breakfast recommendations (eating breakfast on ≥ 5 days per week), and clustering patterns of these health behaviours are described. Results Boys were more active than girls (p < 0.001) and younger adolescents were more active than older adolescents (p < 0.01). Boys ate breakfast on more days per week than girls (p < 0.01) and older adolescents ate more fruit and vegetables than younger adolescents (p < 0.01). Almost 54% of adolescents had multiple risk behaviours and only 6% achieved all three of the recommendations. Girls had significantly more risk factors than boys (p < 0.01). For adolescents with two risk behaviours, the most prevalent cluster was formed by not meeting the physical activity and fruit and vegetable recommendations. Conclusion Many adolescents fail to meet multiple diet and physical activity recommendations, highlighting that physical activity and dietary behaviours do not occur in isolation. Future research should investigate how best to achieve multiple health behaviour change in adolescent boys and girls. PMID:19624822

  17. NATIONAL HUMAN ACTIVITY PATTERN SURVEY (NHAPS): USE OF NATIONWIDE ACTIVITY DATA FOR HUMAN EXPOSURE ASSESSMENT

    EPA Science Inventory

    The National Human Activity Pattern Survey (NHAPS) was initiated to fill a need for updated activity information on a nationwide scale. Several recent exposure field monitoring studies have shown that human activities play a critical role in explaining the variation in human expo...

  18. User Activity Recognition in Smart Homes Using Pattern Clustering Applied to Temporal ANN Algorithm.

    PubMed

    Bourobou, Serge Thomas Mickala; Yoo, Younghwan

    2015-01-01

    This paper discusses the possibility of recognizing and predicting user activities in the IoT (Internet of Things) based smart environment. The activity recognition is usually done through two steps: activity pattern clustering and activity type decision. Although many related works have been suggested, they had some limited performance because they focused only on one part between the two steps. This paper tries to find the best combination of a pattern clustering method and an activity decision algorithm among various existing works. For the first step, in order to classify so varied and complex user activities, we use a relevant and efficient unsupervised learning method called the K-pattern clustering algorithm. In the second step, the training of smart environment for recognizing and predicting user activities inside his/her personal space is done by utilizing the artificial neural network based on the Allen's temporal relations. The experimental results show that our combined method provides the higher recognition accuracy for various activities, as compared with other data mining classification algorithms. Furthermore, it is more appropriate for a dynamic environment like an IoT based smart home. PMID:26007738

  19. User Activity Recognition in Smart Homes Using Pattern Clustering Applied to Temporal ANN Algorithm

    PubMed Central

    Bourobou, Serge Thomas Mickala; Yoo, Younghwan

    2015-01-01

    This paper discusses the possibility of recognizing and predicting user activities in the IoT (Internet of Things) based smart environment. The activity recognition is usually done through two steps: activity pattern clustering and activity type decision. Although many related works have been suggested, they had some limited performance because they focused only on one part between the two steps. This paper tries to find the best combination of a pattern clustering method and an activity decision algorithm among various existing works. For the first step, in order to classify so varied and complex user activities, we use a relevant and efficient unsupervised learning method called the K-pattern clustering algorithm. In the second step, the training of smart environment for recognizing and predicting user activities inside his/her personal space is done by utilizing the artificial neural network based on the Allen’s temporal relations. The experimental results show that our combined method provides the higher recognition accuracy for various activities, as compared with other data mining classification algorithms. Furthermore, it is more appropriate for a dynamic environment like an IoT based smart home. PMID:26007738

  20. Patterning of sympathetic nerve activity in response to vestibular stimulation

    NASA Technical Reports Server (NTRS)

    Kerman, I. A.; McAllen, R. M.; Yates, B. J.

    2000-01-01

    Growing evidence suggests a role for the vestibular system in regulation of autonomic outflow during postural adjustments. In the present paper we review evidence for the patterning of sympathetic nerve activity elicited by vestibular stimulation. In response to electrical activation of vestibular afferents, firing of sympathetic nerves located throughout the body is altered. However, activity of the renal nerve is most sensitive to vestibular inputs. In contrast, high-intensity simultaneous activation of cutaneous and muscle inputs elicits equivalent changes in firing of the renal, superior mesenteric and lumbar colonic nerves. Responses of muscle vasoconstrictor (MVC) efferents to vestibular stimulation are either inhibitory (Type I) or are comprised of a combination of excitation and inhibition (Type II). Interestingly, single MVC units located in the hindlimb exhibited predominantly Type I responses while those located in the forelimb and face exhibited Type II responses. Furthermore, brachial and femoral arterial blood flows were dissociated in response to vestibular stimulation, such that brachial vascular resistance increased while femoral resistance decreased. These studies demonstrate that vestibulosympathetic reflexes are patterned according to both the anatomical location and innervation target of a particular sympathetic nerve, and can lead to distinct changes in local blood flow.

  1. Patterns of frontoparietal activation as a marker for unsuccessful visuospatial processing in healthy aging.

    PubMed

    Drag, Lauren L; Light, Sharee N; Langenecker, Scott A; Hazlett, Kathleen E; Wilde, Elisabeth A; Welsh, Robert; Steinberg, Brett A; Bieliauskas, Linas A

    2016-09-01

    Visuospatial abilities are sensitive to age-related decline, although the neural basis for this decline (and its everyday behavioral correlates) is as yet poorly understood. fMRI was employed to examine age-related differences in patterns of functional activation that underlie changes in visuospatial processing. All participants completed a brief neuropsychological battery and also a figure ground task (FGT) assessing visuospatial processing while fMRI was recorded. Participants included 16 healthy older adults (OA; aged 69-82 years) and 16 healthy younger adults (YA; aged 20-35 years). We examined age-related differences in behavioral performance on the FGT in relation to patterns of fMRI activation. OA demonstrated reduced performance on the FGT task and showed increased activation of supramarginal parietal cortex as well as increased activation of frontal and temporal regions compared to their younger counterparts. Performance on the FGT related to increased supramarginal gyrus activity and increased medial prefrontal activity in OAs, but not YAs. Our results are consistent with an anterior-posterior compensation model. Successful FGT performance requires the perception and integration of multiple stimuli and thus it is plausible that healthy aging may be accompanied by changes in visuospatial processing that mimic a subtle form of dorsal simultanagnosia. Overall, decreased visuospatial processing in OA relates to an altered frontoparietal neurobiological signature that may contribute to the general phenomenon of increasingly fragmented execution of behavior associated with normal aging. PMID:26195153

  2. Prediction of Spatiotemporal Patterns of Neural Activity from Pairwise Correlations

    NASA Astrophysics Data System (ADS)

    Marre, O.; El Boustani, S.; Frégnac, Y.; Destexhe, A.

    2009-04-01

    We designed a model-based analysis to predict the occurrence of population patterns in distributed spiking activity. Using a maximum entropy principle with a Markovian assumption, we obtain a model that accounts for both spatial and temporal pairwise correlations among neurons. This model is tested on data generated with a Glauber spin-glass system and is shown to correctly predict the occurrence probabilities of spatiotemporal patterns significantly better than Ising models only based on spatial correlations. This increase of predictability was also observed on experimental data recorded in parietal cortex during slow-wave sleep. This approach can also be used to generate surrogates that reproduce the spatial and temporal correlations of a given data set.

  3. Prediction of Spatiotemporal Patterns of Neural Activity from Pairwise Correlations

    SciTech Connect

    Marre, O.; El Boustani, S.; Fregnac, Y.; Destexhe, A.

    2009-04-03

    We designed a model-based analysis to predict the occurrence of population patterns in distributed spiking activity. Using a maximum entropy principle with a Markovian assumption, we obtain a model that accounts for both spatial and temporal pairwise correlations among neurons. This model is tested on data generated with a Glauber spin-glass system and is shown to correctly predict the occurrence probabilities of spatiotemporal patterns significantly better than Ising models only based on spatial correlations. This increase of predictability was also observed on experimental data recorded in parietal cortex during slow-wave sleep. This approach can also be used to generate surrogates that reproduce the spatial and temporal correlations of a given data set.

  4. Linking Plagioclase Zoning Patterns to Active Magma Processes

    NASA Astrophysics Data System (ADS)

    Izbekov, P. E.; Nicolaysen, K. P.; Neill, O. K.; Shcherbakov, V.; Plechov, P.; Eichelberger, J. C.

    2015-12-01

    Plagioclase, one of the most common and abundant mineral phases in volcanic products, will vary in composition in response to changes in temperature, pressure, composition of the ambient silicate melt, and melt H2O concentration. Changes in these parameters may cause dissolution or growth of plagioclase crystals, forming characteristic textural and compositional variations (zoning patterns), the complete core-to-rim sequence of which describes events experienced by an individual crystal from its nucleation to the last moments of its growth. Plagioclase crystals in a typical volcanic rock may look drastically dissimilar despite their spatial proximity and the fact that they have erupted together. Although they shared last moments of their growth during magma ascent and eruption, their prior experiences could be very different, as plagioclase crystals often come from different domains of the same magma system. Distinguishing similar zoning patterns, correlating them across the entire population of plagioclase crystals, and linking these patterns to specific perturbations in the magmatic system may provide additional perspective on the variety, extent, and timing of magma processes at active volcanic systems. Examples of magma processes, which may be distinguished based on plagioclase zoning patterns, include (1) cooling due to heat loss, (2) heating and/or pressure build up due to an input of new magmatic material, (3) pressure drop in response to magma system depressurization, and (4) crystal transfer between different magma domains/bodies. This review will include contrasting examples of zoning patters from recent eruptions of Karymsky, Bezymianny, and Tolbachik Volcanoes in Kamchatka, Augustine and Cleveland Volcanoes in Alaska, as well as from the drilling into an active magma body at Krafla, Iceland.

  5. Muscle activation patterns are bilaterally linked during split-belt treadmill walking in humans

    PubMed Central

    Ivanenko, Y. P.; Massaad, F.; Bruijn, S. M.; Duysens, J.; Lacquaniti, F.

    2014-01-01

    There is growing evidence that human locomotion is controlled by flexibly combining a set of basic muscle activity patterns. To explore how these patterns are modified to cope with environmental constraints, 10 healthy young adults 1st walked on a split-belt treadmill at symmetric speeds of 4 and 6 km/h for 2 min. An asymmetric condition was then performed for 10 min in which treadmill speeds for the dominant (fast) and nondominant (slow) sides were 6 and 4 km/h, respectively. This was immediately followed by a symmetric speed condition of 4 km/h for 5 min. Gait kinematics and ground reaction forces were recorded. Electromyography (EMG) was collected from 12 lower limb muscles on each side of the body. Nonnegative matrix factorization was applied to the EMG signals bilaterally and unilaterally to obtain basic activation patterns. A cross-correlation analysis was then used to quantify temporal changes in the activation patterns. During the early (1st 10 strides) and late (final 10 strides) phases of the asymmetric condition, the patterns related to ankle plantar flexor (push-off) of the fast limb and quadriceps muscle (contralateral heel contact) of the slow limb occurred earlier in the gait cycle compared with the symmetric conditions. Moreover, a bilateral temporal alignment of basic patterns between limbs was still maintained in the split-belt condition since a similar shift was observed in the unilateral patterns. The results suggest that the temporal structure of these locomotor patterns is shaped by sensory feedback and that the patterns are bilaterally linked. PMID:24478155

  6. Renal electrolyte circadian rhythms - Independence from feeding and activity patterns

    NASA Technical Reports Server (NTRS)

    Moore-Ede, M. C.; Herd, J. A.

    1977-01-01

    Experiments were conducted on six unanesthetized chair-acclimatized adult male squirrel monkeys (Saimiri sciureus) weighing 600-900 g to determine whether internal synchronization is the result of simple passive dependence of renal excretory rhythms on endogenous rhythms of those variable that influence electrolyte excretion such as dietary intake and muscular activity. Independence of the urinary rhythms from diurnal variations in feeding, drinking, and activity was secured by depriving the animals of food, water, and training them to perform a two-hourly schedule of feeding, drinking, and activity throughout day and night. Results indicate that the internal synchronization which is normally observed between the behavioral and urinary rhythms cannot be explained by any direct dependence of renal function on behavioral patterns. The most probable mechanism for circadian internal synchronization is that the various behavioral and renal rhythms are controlled by potentially independent separate oscillators which are normally kept in synchrony with one another.

  7. Predicting errors from patterns of event-related potentials preceding an overt response.

    PubMed

    Bode, Stefan; Stahl, Jutta

    2014-12-01

    Everyday actions often require fast and efficient error detection and error correction. For this, the brain has to accumulate evidence for errors as soon as it becomes available. This study used multivariate pattern classification techniques for event-related potentials to track the accumulation of error-related brain activity before an overt response was made. Upcoming errors in a digit-flanker task could be predicted after the initiation of an erroneous motor response, ∼90ms before response execution. Channels over motor and parieto-occipital cortices were most important for error prediction, suggesting ongoing perceptual analyses and comparisons of initiated and appropriate motor programmes. Lower response force on error trials as compared to correct trials was observed, which indicates that this early error information was used for attempts to correct for errors before the overt response was made. In summary, our results suggest an early, automatic accumulation of error-related information, providing input for fast correction processes. PMID:25450163

  8. Turing patterns in network-organized activator-inhibitor systems

    NASA Astrophysics Data System (ADS)

    Nakao, Hiroya; Mikhailov, Alexander S.

    2010-07-01

    Turing instability in activator-inhibitor systems provides a paradigm of non-equilibrium self-organization; it has been extensively investigated for biological and chemical processes. Turing instability should also be possible in networks, and general mathematical methods for its treatment have been formulated previously. However, only examples of regular lattices and small networks were explicitly considered. Here we study Turing patterns in large random networks, which reveal striking differences from the classical behaviour. The initial linear instability leads to spontaneous differentiation of the network nodes into activator-rich and activator-poor groups. The emerging Turing patterns become furthermore strongly reshaped at the subsequent nonlinear stage. Multiple coexisting stationary states and hysteresis effects are observed. This peculiar behaviour can be understood in the framework of a mean-field theory. Our results offer a new perspective on self-organization phenomena in systems organized as complex networks. Potential applications include ecological metapopulations, synthetic ecosystems, cellular networks of early biological morphogenesis, and networks of coupled chemical nanoreactors.

  9. Active ultrasound pattern injection system (AUSPIS) for interventional tool guidance.

    PubMed

    Guo, Xiaoyu; Kang, Hyun-Jae; Etienne-Cummings, Ralph; Boctor, Emad M

    2014-01-01

    Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking. PMID:25337784

  10. Active Ultrasound Pattern Injection System (AUSPIS) for Interventional Tool Guidance

    PubMed Central

    Guo, Xiaoyu; Kang, Hyun-Jae; Etienne-Cummings, Ralph; Boctor, Emad M.

    2014-01-01

    Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking. PMID:25337784

  11. Successful Remembering Elicits Event-Specific Activity Patterns in Lateral Parietal Cortex

    PubMed Central

    Chun, Marvin M.

    2014-01-01

    Remembering a past event involves reactivation of content-specific patterns of neural activity in high-level perceptual regions (e.g., ventral temporal cortex, VTC). In contrast, the subjective experience of vivid remembering is typically associated with increased activity in lateral parietal cortex (LPC)—“retrieval success effects” that are thought to generalize across content types. However, the functional significance of LPC activation during memory retrieval remains a subject of active debate. In particular, theories are divided with respect to whether LPC actively represents retrieved content or if LPC activity only scales with content reactivation elsewhere (e.g., VTC). Here, we report a human fMRI study of visual memory recall (faces vs scenes) in which complementary forms of multivoxel pattern analysis were used to test for and compare content reactivation within LPC and VTC. During recall of visual images, we observed robust reactivation of broad category information (face vs scene) in both VTC and LPC. Moreover, recall-related activity patterns in LPC, but not VTC, differentiated between individual events. Importantly, these content effects were particularly evident in areas of LPC (namely, angular gyrus) in which activity scaled with subjective reports of recall vividness. These findings provide striking evidence that LPC not only signals that memories have been successfully recalled, but actively represents what is being remembered. PMID:24899726

  12. Using ILP to Identify Pathway Activation Patterns in Systems Biology

    PubMed Central

    Neaves, Samuel R; Millard, Louise A C; Tsoka, Sophia

    2016-01-01

    We show a logical aggregation method that, combined with propositionalization methods, can construct novel structured biological features from gene expression data. We do this to gain understanding of pathway mechanisms, for instance, those associated with a particular disease. We illustrate this method on the task of distinguishing between two types of lung cancer; Squamous Cell Carcinoma (SCC) and Adenocarcinoma (AC). We identify pathway activation patterns in pathways previously implicated in the development of cancers. Our method identified a model with comparable predictive performance to the winning algorithm of a recent challenge, while providing biologically relevant explanations that may be useful to a biologist. PMID:27478883

  13. Circadian Patterns of Wikipedia Editorial Activity: A Demographic Analysis

    PubMed Central

    Yasseri, Taha; Sumi, Robert; Kertész, János

    2012-01-01

    Wikipedia (WP) as a collaborative, dynamical system of humans is an appropriate subject of social studies. Each single action of the members of this society, i.e., editors, is well recorded and accessible. Using the cumulative data of 34 Wikipedias in different languages, we try to characterize and find the universalities and differences in temporal activity patterns of editors. Based on this data, we estimate the geographical distribution of editors for each WP in the globe. Furthermore we also clarify the differences among different groups of WPs, which originate in the variance of cultural and social features of the communities of editors. PMID:22272279

  14. Differential Activation Patterns in the Same Brain Region Led to Opposite Emotional States.

    PubMed

    Shibata, Kazuhisa; Watanabe, Takeo; Kawato, Mitsuo; Sasaki, Yuka

    2016-09-01

    In human studies, how averaged activation in a brain region relates to human behavior has been extensively investigated. This approach has led to the finding that positive and negative facial preferences are represented by different brain regions. However, using a functional magnetic resonance imaging (fMRI) decoded neurofeedback (DecNef) method, we found that different patterns of neural activations within the cingulate cortex (CC) play roles in representing opposite directions of facial preference. In the present study, while neutrally preferred faces were presented, multi-voxel activation patterns in the CC that corresponded to higher (or lower) preference were repeatedly induced by fMRI DecNef. As a result, previously neutrally preferred faces became more (or less) preferred. We conclude that a different activation pattern in the CC, rather than averaged activation in a different area, represents and suffices to determine positive or negative facial preference. This new approach may reveal the importance of an activation pattern within a brain region in many cognitive functions. PMID:27608359

  15. DREV activities related to military vehicles robotization

    NASA Astrophysics Data System (ADS)

    Montminy, B.

    The Defence Research Establishment Valcartier (DREV) is involved in a number of activities aimed at improving the performance of systems installed aboard military vehicles, automating functions normally carried out by human operators, and adding new functions that become essential to cope with new scenarios and threats. These activities relate to the development of sensors that sense the surrounding environment, processors that interpret the sensor data, and actuators that perform various robotic actions. DREV research related to those activities is reviewed as they relate to robotics which continues to increase the portion of vehicular function that is carried out autonomously. Of special interest is the CF aircraft robotization project which aims to develop an autonomous integrated aircraft protection system to detect and counter threats without any human intervention. This research involves development of means for passive surveillance of the surrounding environment, processing of multisensor data, triggering of sensing-aid devices, and actuation of countermeasures that modify the environment.

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

    PubMed

    Cichon, Nicole B; Denker, Michael; Grün, Sonja; Hanganu-Opatz, Ileana L

    2014-01-01

    Flexible communication within the brain, which relies on oscillatory activity, is not confined to adult neuronal networks. Experimental evidence has documented the presence of discontinuous patterns of oscillatory activity already during early development. Their highly variable spatial and time-frequency organization has been related to region specificity. However, it might be equally due to the absence of unitary criteria for classifying the early activity patterns, since they have been mainly characterized by visual inspection. Therefore, robust and unbiased methods for categorizing these discontinuous oscillations are needed for increasingly complex data sets from different labs. Here, we introduce an unsupervised detection and classification algorithm for the discontinuous activity patterns of rodents during early development. For this, in a first step time windows with discontinuous oscillations vs. epochs of network "silence" were identified. In a second step, the major features of detected events were identified and processed by principal component analysis for deciding on their contribution to the classification of different oscillatory patterns. Finally, these patterns were categorized using an unsupervised cluster algorithm. The results were validated on manually characterized neonatal spindle bursts (SB), which ubiquitously entrain neocortical areas of rats and mice, and prelimbic nested gamma spindle bursts (NG). Moreover, the algorithm led to satisfactory results for oscillatory events that, due to increased similarity of their features, were more difficult to classify, e.g., during the pre-juvenile developmental period. Based on a linear classification, the optimal number of features to consider increased with the difficulty of detection. This algorithm allows the comparison of neonatal and pre-juvenile oscillatory patterns in their spatial and temporal organization. It might represent a first step for the unbiased elucidation of activity patterns

  17. Prevalence and patterns of combat sport related maxillofacial injuries

    PubMed Central

    Shirani, Gholamreza; Kalantar Motamedi, Mohammad Hosein; Ashuri, Alireza; Eshkevari, Pooyan Sadr

    2010-01-01

    Aim: This study was designed to assess the prevalence, distribution, and patterns of injury among athletes engaged in combat sports and compare the prevalence, pattern, and types of oral and maxillofacial trauma in these athletes. Materials and Methods: A total of 120 male athletes engaged in four combat sports (boxing, taekwondo, kickboxing, and Muay Thai) who had sustained bodily trauma were studied; 95 subjects with at least one traumatic injury to the face requiring treatment were referred to us by the physician team. The type of injury (facial laceration, facial fractures, jaw dislocation, etc.), site of facial injury (jaw, nose, malar bone, teeth, etc.), dental injuries (tooth fracture, displacement, luxation, and avulsion), causative sport (boxing, taekwondo, kickboxing, and Muay Thai) as well as demographic data were recorded. Injuries were examined clinically and radiographically, and treated accordingly by a specialist. Treatment data and demographics were recorded for each subject. Recorded data were assessed, and χ2, ANOVA, and Kruskal–Wallis tests were used to statistically analyze and compare the data. Results: Of 120 subjects, 95 male subjects (79.2%), aged 18–25 years (avg. 20 years), had at least one traumatic injury to the face requiring medical treatment. These injuries included facial laceration, bone fractures (nose, mandible, and zygoma), dental injuries (displacement, luxation, fracture, and avulsion), and mandibular dislocation which were recorded in 83 (69.2%), 55 (45.1%), 53 (44.2%), and 8 (6.7%) cases respectively. Statistically significant differences were encountered among various injuries and the sports; kickboxing caused the most maxillofacial injuries and was identified as more injurious. Tooth fractures (59.7%) were the most common dental injuries, and the nose (84.7%) was the most frequently fractured facial bone. Lacerations were more common in Thai-boxers (93.3%). Injuries were significantly greater in professional rather

  18. Vision Drives Correlated Activity without Patterned Spontaneous Activity in Developing Xenopus Retina

    PubMed Central

    Demas, James A.; Payne, Hannah; Cline, Hollis T.

    2011-01-01

    Developing amphibians need vision to avoid predators and locate food before visual system circuits fully mature. Xenopus tadpoles can respond to visual stimuli as soon as retinal ganglion cells (RGCs) innervate the brain, however, in mammals, chicks and turtles, RGCs reach their central targets many days, or even weeks, before their retinas are capable of vision. In the absence of vision, activity-dependent refinement in these amniote species is mediated by waves of spontaneous activity that periodically spread across the retina, correlating the firing of action potentials in neighboring RGCs. Theory suggests that retinorecipient neurons in the brain use patterned RGC activity to sharpen the retinotopy first established by genetic cues. We find that in both wild type and albino Xenopus tadpoles, RGCs are spontaneously active at all stages of tadpole development studied, but their population activity never coalesces into waves. Even at the earliest stages recorded, visual stimulation dominates over spontaneous activity and can generate patterns of RGC activity similar to the locally correlated spontaneous activity observed in amniotes. In addition, we show that blocking AMPA and NMDA type glutamate receptors significantly decreases spontaneous activity in young Xenopus retina, but that blocking GABAA receptor blockers does not. Our findings indicate that vision drives correlated activity required for topographic map formation. They further suggest that developing retinal circuits in the two major subdivisions of tetrapods, amphibians and amniotes, evolved different strategies to supply appropriately patterned RGC activity to drive visual circuit refinement. PMID:21312343

  19. Lower arm electromyography (EMG) activity detection using local binary patterns.

    PubMed

    McCool, Paul; Chatlani, Navin; Petropoulakis, Lykourgos; Soraghan, John J; Menon, Radhika; Lakany, Heba

    2014-09-01

    This paper presents a new electromyography activity detection technique in which 1-D local binary pattern histograms are used to distinguish between periods of activity and inactivity in myoelectric signals. The algorithm is tested on forearm surface myoelectric signals occurring due to hand gestures. The novel features of the presented method are that: 1) activity detection is performed across multiple channels using few parameters and without the need for majority vote mechanisms, 2) there are no per-channel thresholds to be tuned, which makes the process of activity detection easier and simpler to implement and less prone to errors, 3) it is not necessary to measure the properties of the signal during a quiescent period before using the algorithm. The algorithm is compared to other offline single- and double-threshold activity detection methods and, for the data sets tested, it is shown to have a better overall performance with greater tolerance to the noise in the real data set used. PMID:24802139

  20. Turing Patterns in Estuarine Sediments by Microbiological Activity

    NASA Astrophysics Data System (ADS)

    De Morais Mendonca Teles, Antonio

    2016-07-01

    The use of Turing mechanisms and lattice Lotka-Volterra model (LLV), also by means of the non-extensive statistical mechanics, can mathematically describe well the phenomena of clustering and their associated boundaries with fractal dimensionality, which occurs in various natural situations, among them, biogeochemical processes via microorganisms in estuarine and marine sediments on the planet Earth. The author did an experimental analysis in field work which took into account the spatial and temporal behavior of Turing patterns, in the form of microbial activity within estuarine subsurface sediments. We show we can find the characteristics of clustering and fractallity which are present in the dynamical LLV model and Turing patterns mechanisms, and the non-extensive statistical mechanics could be used to find the q-entropy (Sq), and other non-equilibrium statistical parameters of the studied estuarine (Caraís lagoon) subsurface biogeochemical system. In this paper, the author suggests that such kinds of subsurface ecological systems are of interest to Astrobiology because if we find Turing-type clustered geomorphological patterns, below meter scale, on the near subsurface and inside rocks at the surface of planet Mars, and also find non-equilibrium statistical parameters (temperature, [F], [C], [S], etc.), displaying Turing-type mechanism, in the aquatic environments of the internal seas of planets Jupiter's moon Europa and the internal global ocean of Saturn's moon Enceladus, that could mean that possible hypothetical biogeochemical activities are present in such places. This could be a bio-indicator tool. And with further studies we could find the q-entropy Sq to establish better defined statistical mechanical parameters for such environments and to refine models for their evolution, as we do on planet Earth.

  1. An Active Region Model for Capturing Fractal Flow Patterns inUnsaturated Soils: Model Development

    SciTech Connect

    Liu, Hui-Hai; Zhang, R.; Bodvarsson, Gudmundur S.

    2005-06-11

    Preferential flow commonly observed in unsaturated soils allows rapid movement of solute from the soil surface or vadose zone to the groundwater, bypassing a significant volume of unsaturated soil and increasing the risk of groundwater contamination. A variety of evidence indicates that complex preferential patterns observed from fields are fractals. In this study, we developed a relatively simple active region model to incorporate the fractal flow pattern into the continuum approach. In the model, the flow domain is divided into active and inactive regions. Flow occurs preferentially in the active region (characterized by fractals), and inactive region is simply bypassed. A new constitutive relationship (the portion of the active region as a function of saturation) was derived. The validity of the proposed model is demonstrated by the consistency between field observations and the new constitutive relationship.

  2. Prevalence and patterns of physical activity among medical students in Bangalore, India

    PubMed Central

    Padmapriya, Krishnakumar; Krishna, Pushpa; Rasu, Thenna

    2013-01-01

    Background: Physical activity is one of the leading health indicators. The objective was to study the prevalence and patterns of physical activity among young adults. Methods: 259 Medical students (Men: Women = 116:143) in the age group of 18–22 yrs were interviewed using the official English long version of the International Physical Activity Questionnaire (IPAQ). The total level of physical activity and activity in each of the 4 life domains – work, transport, domestic and gardening and leisure-time were estimated and was expressed as metabolic equivalent-hours per week (MET-hour/week). Results: 41.3 % showed high levels of physical activity, 43.2% and 15.4 % of students showed moderate level and low level of physical activity respectively. 84.6 % (n=219) were engaged in work related activity and 80.7% (n= 209) showed transport related activity. Domestic and gardening physical activity represented 63.7 % (n=165) of individuals total activity and 67.2% of students showed leisure time activity. The average time spent in sitting was 7.06 hrs/day. The median of the total physical activity for the whole sample was 39.13 MET/hour/week and 18.10 for work, 4.40 for transportation, 2.60 for domestic and gardening and 4 for leisure-time activity. There was significant gender difference observed with women having low physical activity. Conclusion: This study provides baseline information about the physical activity levels and patterns including sitting hours among Indian young adults using IPAQ that can used for comparison of data across different parts of world. PMID:26120390

  3. Adolescents: Differences in Friendship Patterns Related to Gender

    ERIC Educational Resources Information Center

    Mjaavatn, Per Egil; Frostad, Per; Pijl, Sip Jan

    2016-01-01

    Based on a survey of 123 Norwegian students aged 14-15 (grade 10) this article will discuss possible gender differences in peer relations, social position and friendship criteria. The students filled in a questionnaire that included sociometry and questions on friendship criteria, self-esteem and social support. We found significant gender…

  4. Spatial Relative Risk Patterns of Autism Spectrum Disorders in Utah

    ERIC Educational Resources Information Center

    Bakian, Amanda V.; Bilder, Deborah A.; Coon, Hilary; McMahon, William M.

    2015-01-01

    Heightened areas of spatial relative risk for autism spectrum disorders (ASD), or ASD hotspots, in Utah were identified using adaptive kernel density functions. Children ages four, six, and eight with ASD from multiple birth cohorts were identified by the Utah Registry of Autism and Developmental Disabilities. Each ASD case was gender-matched to…

  5. Economic Restructuring and Emerging Patterns of Industrial Relations.

    ERIC Educational Resources Information Center

    Sleigh, Stephen R., Ed.

    This book contains nine papers presented during a year-long series of seminars and a conference that analyzed the relationship between economic restructuring and industrial relations involving the joint academics, union leaders, government officials, business executives, and graduate fellows. These analyses include case studies from Western…

  6. Legal Issues Related to Extracurricular Activities.

    ERIC Educational Resources Information Center

    Cary, Jean M.

    1992-01-01

    Legal questions related to extracurricular activities include the following: (1) students "right" to participate; (2) kinds of fees or insurance requirements; (3) regulation of contracts and finances; (4) membership policies acceptable in light of Title IX's prohibition on sex discrimination; (5) reduction of risk of tort liability; and (6) how…

  7. Tools of Oceanography. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Sands, Florence

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  8. Physical Activity Patterns in the Elderly Kashan Population

    PubMed Central

    Sadrollahi, Ali; Hosseinian, Masoumeh; Masoudi Alavi, Negin; Khalili, Zahra; Esalatmanesh, Sophia

    2016-01-01

    Kashan. The pattern of physical activity in the elderly depends on their lifestyle. A promotion of active lifestyles should be a part of health care planning for the elderly. PMID:27621923

  9. Empirical relations between catchment characteristics and discharge patterns in Sweden

    NASA Astrophysics Data System (ADS)

    Lindström, G.; Dahné, J.; Arheimer, B.

    2012-04-01

    In hydrological modelling it is often assumed that catchment characteristics, such as soil type, vegetation, land-use, slope, altitude and climate influence both the magnitude and dynamics of the water discharge characteristics. This presentation demonstrates an inter-site comparison on similarities and dissimilarities in hydrological response from Swedish unregulated catchments with an area less than 2000 km2. Observed daily time-series for about 20 years from 198 sites were analysed to search for and quantify statistical relationships between catchment characteristics and flow characteristics. A number of flow characteristics were calculated, such as the mean, mean annual maximum, peakiness, skewness and percentiles. The catchments were grouped dependent on catchment characteristics (for example >80% forest). The differences between the discharges from different catchment types were analysed both graphically and statistically. A T-test was performed to see if the mean value for the flow characteristics was significantly different from the rest of the catchments. Following the t-test, a set of box-whisker diagrams were made for visual inspection of the results. The results showed that lake percentage is the most important catchment characteristic for most of the flow characteristics. The effect of lakes was therefore treated separately. For lake-free basins soil type was in general more important than land-use. For instance, coarse soils exhibit a sustained base flow, whereas thin soils and bare rock are characterised by peak flows with short duration. Finally, the presentation will give some examples on how the retrieved empirical information was included in a national modelling approach to simulate spatial variability in Swedish water discharge patterns.

  10. Age-Related Neural Oscillation Patterns During the Processing of Temporally Manipulated Speech.

    PubMed

    Rufener, Katharina S; Oechslin, Mathias S; Wöstmann, Malte; Dellwo, Volker; Meyer, Martin

    2016-05-01

    This EEG-study aims to investigate age-related differences in the neural oscillation patterns during the processing of temporally modulated speech. Viewing from a lifespan perspective, we recorded the electroencephalogram (EEG) data of three age samples: young adults, middle-aged adults and older adults. Stimuli consisted of temporally degraded sentences in Swedish-a language unfamiliar to all participants. We found age-related differences in phonetic pattern matching when participants were presented with envelope-degraded sentences, whereas no such age-effect was observed in the processing of fine-structure-degraded sentences. Irrespective of age, during speech processing the EEG data revealed a relationship between envelope information and the theta band (4-8 Hz) activity. Additionally, an association between fine-structure information and the gamma band (30-48 Hz) activity was found. No interaction, however, was found between acoustic manipulation of stimuli and age. Importantly, our main finding was paralleled by an overall enhanced power in older adults in high frequencies (gamma: 30-48 Hz). This occurred irrespective of condition. For the most part, this result is in line with the Asymmetric Sampling in Time framework (Poeppel in Speech Commun 41:245-255, 2003), which assumes an isomorphic correspondence between frequency modulations in neurophysiological patterns and acoustic oscillations in spoken language. We conclude that speech-specific neural networks show strong stability over adulthood, despite initial processes of cortical degeneration indicated by enhanced gamma power. The results of our study therefore confirm the concept that sensory and cognitive processes undergo multidirectional trajectories within the context of healthy aging. PMID:26613726

  11. Cardiovascular regulation pattern of contamination-related disgust: Consistency and context dependence.

    PubMed

    Comtesse, Hannah; Stemmler, Gerhard

    2016-09-01

    The cardiovascular response to contamination-related disgust was proposed to be under parasympathetic or parasympathetic-sympathetic cardiac control. However, findings of physiological disgust responses are inconsistent, possibly due to effects of the emotion induction context and single cardiovascular changes being part of larger cardiovascular regulation patterns. Therefore, we induced an emotionally neutral state and core and contamination disgust in female participants in two induction contexts (auditory script, film clip). Dependent variables were emotion self-reports and 10 cardiovascular factors derived from 23 cardiovascular variables. We found elevated disgust ratings in both induction contexts. On the cardiovascular level, we observed consistent increases in a factor indicating vagal cardiac control in both contexts and changes in factors indicating sympathetic activation that were bound to the respective context. These findings support the notion of a parasympathetic dominance of the contamination-related disgust response and underpin the importance of incorporating the induction context in the study of cardiovascular responses to disgust. PMID:27277553

  12. A comparative study of event-related coupling patterns during an auditory oddball task in schizophrenia

    NASA Astrophysics Data System (ADS)

    Bachiller, Alejandro; Poza, Jesús; Gómez, Carlos; Molina, Vicente; Suazo, Vanessa; Hornero, Roberto

    2015-02-01

    Objective. The aim of this research is to explore the coupling patterns of brain dynamics during an auditory oddball task in schizophrenia (SCH). Approach. Event-related electroencephalographic (ERP) activity was recorded from 20 SCH patients and 20 healthy controls. The coupling changes between auditory response and pre-stimulus baseline were calculated in conventional EEG frequency bands (theta, alpha, beta-1, beta-2 and gamma), using three coupling measures: coherence, phase-locking value and Euclidean distance. Main results. Our results showed a statistically significant increase from baseline to response in theta coupling and a statistically significant decrease in beta-2 coupling in controls. No statistically significant changes were observed in SCH patients. Significance. Our findings support the aberrant salience hypothesis, since SCH patients failed to change their coupling dynamics between stimulus response and baseline when performing an auditory cognitive task. This result may reflect an impaired communication among neural areas, which may be related to abnormal cognitive functions.

  13. Spatial relative risk patterns of Autism Spectrum Disorders in Utah

    PubMed Central

    Bakian, Amanda V.; Bilder, Deborah; Coon, Hilary; McMahon, William

    2015-01-01

    Heightened areas of spatial relative risk for ASD, or ASD hotspots, in Utah were identified using adaptive kernel density functions. Children ages four, six and eight with ASD from multiple birth cohorts were identified by the Utah Registry of Autism and Developmental Disabilities (URADD). Each ASD case was gender-matched to 20 birth cohort controls. Demographic and socioeconomic characteristics of children born inside versus outside ASD hotspots were compared. ASD hotspots were found in the surveillance area for all but one birth cohort and age group sample; maximum relative risk in these hotspots ranged from 1.8 to 3.0. Associations were found between higher socioeconomic status (SES) and birth residence in an ASD hotspot in five out of six birth cohort and age group samples. PMID:25241009

  14. Pattern reactivation co-varies with activity in the core recollection network during source memory.

    PubMed

    Leiker, Emily K; Johnson, Jeffrey D

    2015-08-01

    Neuroimaging studies of episodic memory have consistently demonstrated that memory retrieval involves reactivating patterns of neural activity that were present during encoding, and these effects are thought to reflect the qualitative retrieval (recollection) of information that is specific to the content of an episode. By contrast, recollection is also accompanied by other neural correlates that generalize across episodic content and are consequently referred to as the "core recollection network". The neural mechanism by which these specific and core effects interact to give rise to episodic memory retrieval is largely unknown. The current study addressed this issue by testing for correlations (connectivity) between pattern reactivation and activity in the core recollection network. Subjects encoded a series of words with different tasks and then completed a two-step source memory test, whereby they identified the task (source) previously associated with the word and the confidence of that judgment. Multivariate pattern analysis (MVPA) was used in combination with fMRI to first identify encoding-related neural patterns and then test for their reactivation during retrieval. Consistent with prior findings, the magnitude of reactivation increased with source-memory confidence. Moreover, individual-trial measures of reactivation exhibited positive correlations with activity in multiple regions of the core recollection network. Importantly, evidence of functional connectivity between pattern reactivation and a region of left posterior parietal cortex supports the role of this region in tracking the retrieval of episodic information in service of making subjective memory decisions. PMID:26004057

  15. Patterns of Physical Activity Among Older Adults in New York City

    PubMed Central

    Mooney, Stephen J.; Joshi, Spruha; Cerdá, Magdalena; Quinn, James W.; Beard, John R.; Kennedy, Gary J.; Benjamin, Ebele O.; Ompad, Danielle C.; Rundle, Andrew G.

    2015-01-01

    Introduction Little research to date has explored typologies of physical activity among older adults. An understanding of physical activity patterns may help to both determine the health benefits of different types of activity and target interventions to increase activity levels in older adults. This analysis, conducted in 2014, used a latent class analysis approach to characterize patterns of physical activity in a cohort of older adults. Methods A total of 3,497 men and women aged 65–75 years living in New York City completed the Physical Activity Scale for the Elderly (PASE) in 2011. PASE scale items were used to classify subjects into latent classes. Multinomial regression was then used to relate individual and neighborhood characteristics to class membership. Results Five latent classes were identified: “least active,” “walkers,” “domestic/gardening,” “athletic,” and “domestic/gardening athletic.” Individual-level predictors, including more education, higher income, and better self-reported health, were associated with membership in the more-active classes, particularly the athletic classes. Residential characteristics, including living in single-family housing and living in the lower-density boroughs of New York City, were predictive of membership in one of the domestic/gardening classes. Class membership was associated with BMI even after controlling for total PASE score. Conclusions This study suggests that individual and neighborhood characteristics are associated with distinct physical activity patterns in a group of older urban adults. These patterns are associated with body habitus independent of overall activity. PMID:26091927

  16. Cortical Activation Patterns of Bodily Attention triggered by Acupuncture Stimulation

    PubMed Central

    Jung, Won-Mo; Lee, In-Seon; Wallraven, Christian; Ryu, Yeon-Hee; Park, Hi-Joon; Chae, Younbyoung

    2015-01-01

    We investigated commonalities and differences in brain responses to enhanced bodily attention around acupuncture points with and without stimulation. Fourteen participants received acupuncture needles at both PC6 and HT7 acupoints in the left hand. To enhance bodily attention to acupoints, participants responded to the locations of stimulations in a two-alternative forced choice task. Two fMRI scans were taken in a block design: session 1 labeled with manual stimulation (genuine stimulation) and session 2 labeled with electro-acupuncture (pseudo-stimulation). To compare cortical activation patterns, data were analyzed using the Freesurfer software package. Both genuine-and pseudo-stimulation resulted in brain activations in the insula, anterior cingulate cortex, secondary somatosensory cortex, superior parietal cortex, and brain deactivation in the medial prefrontal cortex, posterior cingulate cortex, inferior parietal cortex, and the parahippocampus. Genuine acupuncture stimulation exhibited greater brain activation in the posterior insula, posterior operculum and the caudal part of the anterior cingulate cortex, compared with pseudo-stimulation. We demonstrated that enhanced bodily attention triggered by genuine acupuncture stimulation can activate the salience network and deactivate the default mode network regardless of the type of stimulation. The component of enhanced attention to a certain part of the body is significant in the brain response to acupuncture stimulation. PMID:26211895

  17. Abnormal patterns of displacement activities: a review and reinterpretation.

    PubMed

    Anselme, Patrick

    2008-09-01

    A series of important theoretical contributions flourished in the years 1950-1970 about displacement activities -- those 'out-of-context' actions expressed by organisms in stressful situations. Nothing really new has appeared thereafter. Although the models address different issues, such as causal factors of displacement, it appears obvious that they do not provide a unified (coherent) approach; they often explain the same phenomena using very different means and turn out to be contradictory on several points. In addition, some problems currently remain unsolved, especially concerning the fact that displacement activities exhibit 'abnormalities' of expression in comparison with the same activities performed in usual context. Each model is here described and criticized in order to evaluate its explanatory power and allow the identification of specific limits. A new, integrative model -- the Anticipatory Dynamics Model (or ADM) -- then attempts to overcome the failures of previous models. The ADM suggests that abnormal patterns of displacement activities result from attentional interference caused by a thwarting experience or conflicting motivations. At least one theoretical prediction of the ADM can be differentiated from that of any other model. PMID:18554824

  18. Relative stability of multipeak localized patterns of cavity solitons

    SciTech Connect

    Vladimirov, A. G.; Lefever, R.; Tlidi, M.

    2011-10-15

    We study the relative stability of different one-dimensional (1D) and two-dimensional (2D) clusters of closely packed localized peaks of the Swift-Hohenberg equation. In the 1D case, we demonstrate numerically the existence of a spatial Maxwell transition point where all clusters involving up to 15 peaks are equally stable. Above (below) this point, clusters become more (less) stable when their number of peaks increases. In the 2D case, since clusters involving more than two peaks may exhibit distinct spatial arrangements, this point splits into a set of Maxwell transition points.

  19. Modeling patterns in data using linear and related models

    SciTech Connect

    Engelhardt, M.E.

    1996-06-01

    This report considers the use of linear models for analyzing data related to reliability and safety issues of the type usually associated with nuclear power plants. The report discusses some of the general results of linear regression analysis, such as the model assumptions and properties of the estimators of the parameters. The results are motivated with examples of operational data. Results about the important case of a linear regression model with one covariate are covered in detail. This case includes analysis of time trends. The analysis is applied with two different sets of time trend data. Diagnostic procedures and tests for the adequacy of the model are discussed. Some related methods such as weighted regression and nonlinear models are also considered. A discussion of the general linear model is also included. Appendix A gives some basic SAS programs and outputs for some of the analyses discussed in the body of the report. Appendix B is a review of some of the matrix theoretic results which are useful in the development of linear models.

  20. Judgments Relative to Patterns: How Temporal Sequence Patterns Affect Judgments and Memory

    ERIC Educational Resources Information Center

    Kusev, Petko; Ayton, Peter; van Schaik, Paul; Tsaneva-Atanasova, Krasimira; Stewart, Neil; Chater, Nick

    2011-01-01

    RESix experiments studied relative frequency judgment and recall of sequentially presented items drawn from 2 distinct categories (i.e., city and animal). The experiments show that judged frequencies of categories of sequentially encountered stimuli are affected by certain properties of the sequence configuration. We found (a) a "first-run effect"…

  1. Advance cueing produces enhanced action-boundary patterns of spike activity in the sensorimotor striatum.

    PubMed

    Barnes, Terra D; Mao, Jian-Bin; Hu, Dan; Kubota, Yasuo; Dreyer, Anna A; Stamoulis, Catherine; Brown, Emery N; Graybiel, Ann M

    2011-04-01

    One of the most characteristic features of habitual behaviors is that they can be evoked by a single cue. In the experiments reported here, we tested for the effects of such advance cueing on the firing patterns of striatal neurons in the sensorimotor striatum. Rats ran in a T-maze with instruction cues about the location of reward given at the start of the runs. This advance cueing about reward produced a highly augmented task-bracketing pattern of activity at the beginning and end of procedural task performance relative to the patterns found previously with midtask cueing. Remarkably, the largest increase in activity early during the T-maze runs was not associated with the instruction cues themselves, the earliest predictors of reward; instead, the highest peak of early activity was associated with the beginning of the motor period of the task. We suggest that the advance cueing, reducing midrun demands for decision making but adding a working-memory load, facilitated chunking of the maze runs as executable scripts anchored to sensorimotor aspects of the task and unencumbered by midtask decision-making demands. Our findings suggest that the acquisition of stronger task-bracketing patterns of striatal activity in the sensorimotor striatum could reflect this enhancement of behavioral chunking. Deficits in such representations of learned sequential behaviors could contribute to motor and cognitive problems in a range of neurological disorders affecting the basal ganglia, including Parkinson's disease. PMID:21307317

  2. Advance cueing produces enhanced action-boundary patterns of spike activity in the sensorimotor striatum

    PubMed Central

    Barnes, Terra D.; Mao, Jian-Bin; Hu, Dan; Kubota, Yasuo; Dreyer, Anna A.; Stamoulis, Catherine; Brown, Emery N.

    2011-01-01

    One of the most characteristic features of habitual behaviors is that they can be evoked by a single cue. In the experiments reported here, we tested for the effects of such advance cueing on the firing patterns of striatal neurons in the sensorimotor striatum. Rats ran in a T-maze with instruction cues about the location of reward given at the start of the runs. This advance cueing about reward produced a highly augmented task-bracketing pattern of activity at the beginning and end of procedural task performance relative to the patterns found previously with midtask cueing. Remarkably, the largest increase in activity early during the T-maze runs was not associated with the instruction cues themselves, the earliest predictors of reward; instead, the highest peak of early activity was associated with the beginning of the motor period of the task. We suggest that the advance cueing, reducing midrun demands for decision making but adding a working-memory load, facilitated chunking of the maze runs as executable scripts anchored to sensorimotor aspects of the task and unencumbered by midtask decision-making demands. Our findings suggest that the acquisition of stronger task-bracketing patterns of striatal activity in the sensorimotor striatum could reflect this enhancement of behavioral chunking. Deficits in such representations of learned sequential behaviors could contribute to motor and cognitive problems in a range of neurological disorders affecting the basal ganglia, including Parkinson's disease. PMID:21307317

  3. Homologues of serotonergic central pattern generator neurons in related nudibranch molluscs with divergent behaviors.

    PubMed

    Newcomb, James M; Katz, Paul S

    2007-04-01

    Homologues of a neuron that contributes to a species-specific behavior were identified and characterized in species lacking that behavior. The nudibranch Tritonia diomedea swims by flexing its body dorsally and ventrally. The dorsal swim interneurons (DSIs) are components of the central pattern generator (CPG) underlying this rhythmic motor pattern and also activate crawling. Homologues of the DSIs were identified in six nudibranchs that do not exhibit dorsal-ventral swimming: Tochuina tetraquetra, Melibe leonina, Dendronotus iris, D. frondosus, Armina californica, and Triopha catalinae. Homology was based upon shared features that distinguish the DSIs from all other neurons: (1) serotonin immunoreactivity, (2) location in the Cerebral serotonergic posterior (CeSP) cluster, and (3) axon projection to the contralateral pedal ganglion. The DSI homologues, named CeSP-A neurons, share additional features with the DSIs: irregular basal firing, synchronous inputs, electrical coupling, and reciprocal inhibition. Unlike the DSIs, the CeSP-A neurons were not rhythmically active in response to nerve stimulation. The CeSP-A neurons in Tochuina and Triopha also excited homologues of the Tritonia Pd5 neuron, a crawling efferent. Thus, the CeSP-A neurons and the DSIs may be part of a conserved network related to crawling that may have been co-opted into a rhythmic swim CPG in Tritonia. PMID:17180703

  4. Active sensing in the categorization of visual patterns

    PubMed Central

    Yang, Scott Cheng-Hsin; Lengyel, Máté; Wolpert, Daniel M

    2016-01-01

    Interpreting visual scenes typically requires us to accumulate information from multiple locations in a scene. Using a novel gaze-contingent paradigm in a visual categorization task, we show that participants' scan paths follow an active sensing strategy that incorporates information already acquired about the scene and knowledge of the statistical structure of patterns. Intriguingly, categorization performance was markedly improved when locations were revealed to participants by an optimal Bayesian active sensor algorithm. By using a combination of a Bayesian ideal observer and the active sensor algorithm, we estimate that a major portion of this apparent suboptimality of fixation locations arises from prior biases, perceptual noise and inaccuracies in eye movements, and the central process of selecting fixation locations is around 70% efficient in our task. Our results suggest that participants select eye movements with the goal of maximizing information about abstract categories that require the integration of information from multiple locations. DOI: http://dx.doi.org/10.7554/eLife.12215.001 PMID:26880546

  5. Guiding Catalytically Active Particles with Chemically Patterned Surfaces

    NASA Astrophysics Data System (ADS)

    Uspal, W. E.; Popescu, M. N.; Dietrich, S.; Tasinkevych, M.

    2016-07-01

    Catalytically active Janus particles suspended in solution create gradients in the chemical composition of the solution along their surfaces, as well as along any nearby container walls. The former leads to self-phoresis, while the latter gives rise to chemiosmosis, providing an additional contribution to self-motility. Chemiosmosis strongly depends on the molecular interactions between the diffusing chemical species and the wall. We show analytically, using an approximate "point-particle" approach, that by chemically patterning a planar substrate one can direct the motion of Janus particles: the induced chemiosmotic flows can cause particles to either "dock" at the chemical step between the two materials or follow a chemical stripe. These theoretical predictions are confirmed by full numerical calculations. Generically, docking occurs for particles which tend to move away from their catalytic caps, while stripe following occurs in the opposite case. Our analysis reveals the physical mechanisms governing this behavior.

  6. Hidden Stages of Cognition Revealed in Patterns of Brain Activation.

    PubMed

    Anderson, John R; Pyke, Aryn A; Fincham, Jon M

    2016-09-01

    To advance cognitive theory, researchers must be able to parse the performance of a task into its significant mental stages. In this article, we describe a new method that uses functional MRI brain activation to identify when participants are engaged in different cognitive stages on individual trials. The method combines multivoxel pattern analysis to identify cognitive stages and hidden semi-Markov models to identify their durations. This method, applied to a problem-solving task, identified four distinct stages: encoding, planning, solving, and responding. We examined whether these stages corresponded to their ascribed functions by testing whether they are affected by appropriate factors. Planning-stage duration increased as the method for solving the problem became less obvious, whereas solving-stage duration increased as the number of calculations to produce the answer increased. Responding-stage duration increased with the difficulty of the motor actions required to produce the answer. PMID:27440808

  7. Analysis of photo-pattern sensitivity in patients with Pokemon-related symptoms.

    PubMed

    Funatsuka, Makoto; Fujita, Michinari; Shirakawa, Seigo; Oguni, Hirokazu; Osawa, Makiko

    2003-01-01

    This study was designed to analyze photo-pattern sensitivity in patients who developed acute neurologic symptoms associated with watching an animated television program, "Pokemon." The 18 patients (13 females and five males) underwent electroencephalograms and photo-pattern stimulation testing, including special stimulation test batteries (strobe-pattern test and cathode ray tube-pattern test). Photo-pattern sensitivity was confirmed in 16 patients with and without seizure episodes. The strobe-pattern test including a white flickering light test (with eyes open, closed, and open or closed), and the cathode ray tube-pattern test each induced a photo-paroxysmal response in more than 80% of patients. However, with the eyes closed only, as is common in Japan, the photo-paroxysmal response induction rate with a white flickering light stimulus was significantly lower (43%). In the cathode ray tube-pattern test, higher spatial frequencies produced higher rates of photo-paroxysmal response induction. It was demonstrated that underlying photo-pattern sensitivity is more accurately investigated by our method than by standard intermittent photic stimulation alone. By characterizing underlying photo-pattern sensitivity and identifying predisposing factors more precisely, we can develop better guidelines for prevention of a second "Pokemon" incident. According to the results of the present cathode ray tube-pattern test, pattern sensitivity (especially spatial resolution) appears to also be involved in Pokemon-related symptoms, in addition to chromatic sensitivity. PMID:12657417

  8. Adult food intake patterns are related to adult and childhood socioeconomic status.

    PubMed

    Hare-Bruun, Helle; Togo, Per; Andersen, Lars Bo; Heitmann, Berit Lilienthal

    2011-05-01

    Our objective was to examine the influence of adult and childhood socioeconomic status (SES) on attained adult food intake patterns. We used data from a 20- to 22-y follow-up study of 1904 Danish teenagers. The baseline survey was conducted partly in 1983 and partly in 1985 and the follow-up survey was conducted in 2005. Dietary data were collected at follow-up using a 195-item FFQ. Food patterns were derived from principal component analysis. Two food patterns labeled "traditional-western food pattern" and "green food pattern" were identified. In men, adult SES was inversely associated with adherence to the traditional-western food pattern. High adherence to the green food pattern was positively related to high adult SES in both sexes. Among women, those with high SES in childhood had higher green food pattern factor scores than those with low childhood SES, regardless of adult SES. Among men, those with high adult SES had higher green food pattern factor scores than those with low adult SES, regardless of childhood SES. In conclusion, socioeconomic position is important for the development of adult food intake patterns. However, childhood SES seems more important for adult female food intake patterns, whereas adult SES seems more important for adult male food intake patterns. PMID:21451129

  9. Mars - The north polar sand sea and related wind patterns

    NASA Technical Reports Server (NTRS)

    Tsoar, H.; Greeley, R.; Peterfreund, A. R.

    1979-01-01

    Viking Orbiter 2 images of the north polar region reveal an enormous sand sea (erg) covering an area of greater than 500,000 sq km around the perennial ice cap. All dunes are either transverse or barchan. The various dune morphologies and modifications of primary dune types reflect a wind regime having more than one wind direction. In the summer, two major wind directions prevail: (1) off-pole winds that become easterly due to coriolis forces and (2) on-pole winds that become westerly. During the winter and/or spring, only the on-pole winds exist. Strong winds greater than 75 m/s are required for sand accumulation to form the thick transverse dunes. The strongest winds in the north polar region are thought to exist during summer over the transverse dune field between 110 deg and 220 deg W; this area is a relatively warm belt (temperature greater than 230 K) between two ice zones (temperature less than 220 K). The lack of well-developed longitudinal dunes implies that the dune field is young. The relationship of the present dune field to the perennial ice indicates that the dunes began to form after the formation of the present ice cap.

  10. A comparative Study of Circulation Patterns at Active Lava Lakes

    NASA Astrophysics Data System (ADS)

    Lev, Einat; Oppenheimer, Clive; Spampinato, Letizia; Hernandez, Pedro; Unglert, Kathi

    2016-04-01

    Lava lakes present a rare opportunity to study magma dynamics in a large scaled-up "crucible" and provide a unique natural laboratory to ground-truth dynamic models of magma circulation. The persistence of lava lakes allows for long-term observations of flow dynamics and of lava properties, especially compared to surface lava flows. There are currently five persistent lava lakes in the world: Halemaumau in Kilauea (Hawaii, USA), Erta Ale (Ethiopia), Nyiragongo (Congo), Erebus (Antarctica), and Villarica (Chile). Marum and Benbow craters of Ambrym volcano (Vanuatu) and Masaya (Nicaragua) have often hosted lava lakes as well. We use visible-light and thermal infrared time-lapse and video footage collected at all above lakes (except Villarica, where the lake is difficult to observe), and compare the circulation patterns recorded. We calculate lake surface motion from the footage using the optical flow method (Lev et al., 2012) to produce 2D velocity fields. We mined both the surface temperature field and the surface velocity field for patterns using machine learning techniques such as "self-organizing maps (SOMs)" and "principle component analysis (PCA)". We use automatic detection technique to study the configuration of crustal plates at the lakes' surface. We find striking differences among the lakes, in flow direction, flow speed, frequency of changes in flow direction and speed, location and consistency of upwelling and downwelling, and crustal plate configuration. We relate the differences to lake size, shallow conduit geometry, lava viscosity, crystal and gas content, and crust integrity.

  11. Arousal and locomotion make distinct contributions to cortical activity patterns and visual encoding.

    PubMed

    Vinck, Martin; Batista-Brito, Renata; Knoblich, Ulf; Cardin, Jessica A

    2015-05-01

    Spontaneous and sensory-evoked cortical activity is highly state-dependent, yet relatively little is known about transitions between distinct waking states. Patterns of activity in mouse V1 differ dramatically between quiescence and locomotion, but this difference could be explained by either motor feedback or a change in arousal levels. We recorded single cells and local field potentials from area V1 in mice head-fixed on a running wheel and monitored pupil diameter to assay arousal. Using naturally occurring and induced state transitions, we dissociated arousal and locomotion effects in V1. Arousal suppressed spontaneous firing and strongly altered the temporal patterning of population activity. Moreover, heightened arousal increased the signal-to-noise ratio of visual responses and reduced noise correlations. In contrast, increased firing in anticipation of and during movement was attributable to locomotion effects. Our findings suggest complementary roles of arousal and locomotion in promoting functional flexibility in cortical circuits. PMID:25892300

  12. Implications of climatic seasonality on activity patterns and resource use by sympatric peccaries in northern Pantanal.

    PubMed

    Hofmann, Gabriel Selbach; Coelho, Igor Pfeifer; Bastazini, Vinicius Augusto Galvão; Cordeiro, José Luís Passos; de Oliveira, Luiz Flamarion Barbosa

    2016-03-01

    We evaluated the effects of climate seasonality from a thermal and water availability perspective on the activity patterns and resource use of Pecari tajacu and Tayassu pecari during wet and dry seasons in the northeastern Brazilian Pantanal. We used camera traps and temperature sensors to record species activity patterns in relation to temperature, established five habitat categories based on flooding intensity and local vegetation characteristics, assessed the activity patterns of each species in dry and wet periods and in artificial water bodies using circular statistical metrics, and calculated niche amplitude and overlap on three axes (temperature, time, and habitat) in both periods. Peccaries shared a strong resemblance in resource use and in their responses to seasonal variations in the tested gradients. The activity patterns of both species exhibited a significant correlation with air temperature on all the evaluated measures, and both species strongly reduced their activity when the air temperature exceeded 35 °C. High temperatures associated with low water availability were most likely responsible for the changes in species activity patterns, which resulted in an increased temporal overlap in habitat use throughout the dry season. However, the peccaries avoided intensively flooded habitats; therefore, the habitat gradient overlap was greater during the wet period. Our results show that an increase in niche overlap on the environmental gradient as a result of climatic seasonality may be partially compensated by a reduction in other niche dimensions. In this case, temporal partitioning appears to be an important, viable mechanism to reduce competition by potentially competing species. PMID:26219606

  13. Patterns of physical activity and sedentary behaviour in preschool children

    PubMed Central

    2012-01-01

    Background Little is known about patterns of sedentary behavior (SB) and physical activity among preschoolers. Therefore, in this observational study patterns of SB and moderate-to-vigorous physical activity (MVPA) were examined in detail throughout the week in preschool-aged boys and girls. Methods A sample of 703 Melbourne preschool children (387 boys; 4.6 ± 0.7 y) were included in data analysis. SB and MVPA data were collected using accelerometry over an eight-day period. Percentage of time per hour in SB and in MVPA between 08:00 h and 20:00 h was calculated. Multi-level logistic regression models were created to examine the hour-by-hour variability in SB and MVPA for boys and girls across weekdays and weekend days. Odds ratios (OR) were calculated to interpret differences in hour-by-hour SB and MVPA levels between boys and girls, and between weekdays and weekend days. Results The highest SB levels co-occurred with the lowest MVPA levels from the morning till the early afternoon on weekdays, and during the morning and around midday on weekends. Besides, participation in SB was the lowest and participation in MVPA was the highest from the mid afternoon till the evening on weekdays and weekend days. The variability across the hours in SB and, especially, in MVPA was rather small throughout weekdays and weekends. These patterns were found in both boys and girls. During some hours, girls were found to be more likely than boys to demonstrate higher SB levels (OR from 1.08 to 1.16; all p < 0.05) and lower MVPA levels (OR from 0.75 to 0.88; all p < 0.05), but differences were small. During weekends, hour-by-hour SB levels were more likely to be lower (OR from 0.74 to 0.98; all p < 0.05) and hour-by-hour MVPA levels were more likely to be higher (OR from 1.15 to 1.50; all p < 0.05), than during weekdays, in boys and girls. Conclusion Entire weekdays, especially from the morning till the early afternoon, and entire weekend days are opportunities to

  14. Extracting extensor digitorum communis activation patterns using high-density surface electromyography.

    PubMed

    Hu, Xiaogang; Suresh, Nina L; Xue, Cindy; Rymer, William Z

    2015-01-01

    The extensor digitorum communis muscle plays an important role in hand dexterity during object manipulations. This multi-tendinous muscle is believed to be controlled through separate motoneuron pools, thereby forming different compartments that control individual digits. However, due to the complex anatomical variations across individuals and the flexibility of neural control strategies, the spatial activation patterns of the extensor digitorum communis compartments during individual finger extension have not been fully tracked under different task conditions. The objective of this study was to quantify the global spatial activation patterns of the extensor digitorum communis using high-density (7 × 9) surface electromyogram (EMG) recordings. The muscle activation map (based on the root mean square of the EMG) was constructed when subjects performed individual four finger extensions at the metacarpophalangeal joint, at different effort levels and under different finger constraints (static and dynamic). Our results revealed distinct activation patterns during individual finger extensions, especially between index and middle finger extensions, although the activation between ring and little finger extensions showed strong covariance. The activation map was relatively consistent at different muscle contraction levels and for different finger constraint conditions. We also found that distinct activation patterns were more discernible in the proximal-distal direction than in the radial-ulnar direction. The global spatial activation map utilizing surface grid EMG of the extensor digitorum communis muscle provides information for localizing individual compartments of the extensor muscle during finger extensions. This is of potential value for identifying more selective control input for assistive devices. Such information can also provide a basis for understanding hand impairment in individuals with neural disorders. PMID:26500558

  15. Extracting extensor digitorum communis activation patterns using high-density surface electromyography

    PubMed Central

    Hu, Xiaogang; Suresh, Nina L.; Xue, Cindy; Rymer, William Z.

    2015-01-01

    The extensor digitorum communis muscle plays an important role in hand dexterity during object manipulations. This multi-tendinous muscle is believed to be controlled through separate motoneuron pools, thereby forming different compartments that control individual digits. However, due to the complex anatomical variations across individuals and the flexibility of neural control strategies, the spatial activation patterns of the extensor digitorum communis compartments during individual finger extension have not been fully tracked under different task conditions. The objective of this study was to quantify the global spatial activation patterns of the extensor digitorum communis using high-density (7 × 9) surface electromyogram (EMG) recordings. The muscle activation map (based on the root mean square of the EMG) was constructed when subjects performed individual four finger extensions at the metacarpophalangeal joint, at different effort levels and under different finger constraints (static and dynamic). Our results revealed distinct activation patterns during individual finger extensions, especially between index and middle finger extensions, although the activation between ring and little finger extensions showed strong covariance. The activation map was relatively consistent at different muscle contraction levels and for different finger constraint conditions. We also found that distinct activation patterns were more discernible in the proximal–distal direction than in the radial–ulnar direction. The global spatial activation map utilizing surface grid EMG of the extensor digitorum communis muscle provides information for localizing individual compartments of the extensor muscle during finger extensions. This is of potential value for identifying more selective control input for assistive devices. Such information can also provide a basis for understanding hand impairment in individuals with neural disorders. PMID:26500558

  16. Spatiotemporal activity patterns detected from single cell measurements from behaving animals

    NASA Astrophysics Data System (ADS)

    Villa, Alessandro E. P.; Tetko, Igor V.

    1999-03-01

    Precise temporal patterning of activity within and between neurons has been predicted on theoretical grounds, and found in the spike trains of neurons recorded from anesthetized and conscious animals, in association with sensor stimuli and particular phases of task performance. However, the functional significance of such patterning in the generation of behavior has not been confirmed. We recorded from multiple single neurons in regions of rat auditory cortex during the waiting period of a Go/NoGo task. During this time the animal waited for an auditory signal with high cognitive load. Of note is the fact that neural activity during the period analyzed was essentially stationary, with no event related variability in firing. Detected patterns therefore provide a measure of brain state that could not be addressed by standard methods relying on analysis of changes in mean discharge rate. The possibility is discussed that some patterns might reflect a preset bias to a particular response, formed in the waiting period. Others patterns might reflect a state of prior preparation of appropriate neural assemblies for analyzing a signal that is expected but of unknown behavioral valence.

  17. OMP gene deletion results in an alteration in odorant-induced mucosal activity patterns.

    PubMed

    Youngentob, S L; Kent, P F; Margolis, F L

    2003-12-01

    -null and control mice. That is, although the general regions of characteristic activity for different odorants were the same in both mouse strains, the patterns in the null animals were degraded relative to controls. These data suggest therefore that the alterations in mucosal activity may serve as the substrate for the behaviorally observed changes in odorant quality perception in the null mutant. PMID:12917392

  18. Unobtrusive assessment of activity patterns associated with mild cognitive impairment

    PubMed Central

    Hayes, T.L.; Abendroth, F.; Adami, A.; Pavel, M.; Zitzelberger, T.A.; Kaye, J.A.

    2008-01-01

    Background Timely detection of early cognitive impairment is difficult. Measures taken in the clinic reflect a single snapshot of performance that may be confounded by the increased variability typical in aging and disease. We evaluated the use of continuous, long-term and unobtrusive in-home monitoring to assess neurological function in healthy and cognitively impaired elders. Methods Fourteen older adults 65 years and older living independently in the community were monitored in their homes using an unobtrusive sensor system. Measures of walking speed and amount of activity in the home were obtained. Wavelet analysis was used to examine variance in activity at multiple timescales. Results More than 108,000 person-hours of continuous activity data were collected over periods as long as 418 days (mean 315 ± 82 days). The coefficient of variation in the median walking speed was twice as high in the MCI group (0.147 ± 0.074) as compared to the healthy group (0.079 ± 0.027; t11 = 2.266, p<0.03). Furthermore, the 24-hour wavelet variance was greater in the MCI group (MCI: 4.07 ± 0.14, Healthy elderly: 3.79± 0.23; F = 7.58, p=<0.008), indicating that the day-to-day pattern of activity of subjects in the MCI group was more variable than that of the cognitively healthy controls. Conclusions The results not only demonstrate the feasibility of these methods, but also suggest clear potential advantages to this new methodology. This approach may provide an improved means of detecting the earliest transition to MCI compared to conventional episodic testing in a clinic environment. PMID:19012864

  19. Relational Patterns Between Caregivers With PTSD and Their Nonexposed Children: A Review.

    PubMed

    van Ee, Elisa; Kleber, Rolf J; Jongmans, Marian J

    2016-04-01

    The question as to whether or not children can be affected by the traumatization of their parents has been the topic of a long-standing debate. This article provides a critical review of 72 research studies on traumatized parents with symptoms of posttraumatic stress disorder (PTSD), the parent-child interaction, and the impact on their nonexposed child (0-18 years). The evidence suggests that traumatization can cause parenting limitations, and these limitations can disrupt the development of the young child. From the studies reviewed several patterns emerged: Relational patterns of traumatized parents who are observed to be emotionally less available and who perceive their children more negatively than parents without symptoms of PTSD; relational patterns of children who at a young age are easily deregulated or distressed and at an older age are reported to face more difficulties in their psychosocial development than children of parents without symptoms of PTSD; and relational patterns that show remarkable similarities to relational patterns between depressed or anxious parents and their children. Mechanisms such as mentalization, attachment, physiological factors, and the cycle of abuse offer a valuable perspective to further our understanding of the relational patterns. This article builds on previous work by discussing the emerged patterns between traumatized parents and their nonexposed children from a relational and transactional perspective. PMID:25964276

  20. Weather pattern climatology of the Great Plains and the related wind regime

    SciTech Connect

    Barchet, W.R.

    1982-11-01

    The meteorology of the Great Plains can be described as a constant progression of air masses, fronts and cyclonic storm systems. Each of these meteorological conditions can be characterized by identifiable isobaric and related weather parameter patterns. Nine such patterns have been defined to type the weather patterns in the Great Plains. Time series of weather pattern types were produced for 62 stations on the Great Plains. Statistical analyses of these time series produced annual and seasonal frequencies of occurrence of the weather pattern types. Maps of the annual and seasonal frequency of occurrence of weather pattern type are presented for the Great Plains. Persistence and alternation frequencies match what is expected for traveling temperate latitude cyclones, anticyclones and fronts. The wind regime for stations at which the anemometer height and location was constant (and known) for a minimum of three consecutive years was stratified by weather pattern type. Statistical analyses were made to show the response of the wind to the large-scale distribution of air pressure associated with a weather pattern type. The response of the wind to the weather pattern is a site-specific result of the interaction of the large-scale meteorology with local terrain, surface roughness and atmospheric stability. Mean wind speed discriminates between pairs of weather pattern types with better than 75% confidence for more than two-thirds of the possible pairs of weather pattern types.

  1. Spatial patterns of correlated scale size and scale color in relation to color pattern elements in butterfly wings.

    PubMed

    Iwata, Masaki; Otaki, Joji M

    2016-02-01

    Complex butterfly wing color patterns are coordinated throughout a wing by unknown mechanisms that provide undifferentiated immature scale cells with positional information for scale color. Because there is a reasonable level of correspondence between the color pattern element and scale size at least in Junonia orithya and Junonia oenone, a single morphogenic signal may contain positional information for both color and size. However, this color-size relationship has not been demonstrated in other species of the family Nymphalidae. Here, we investigated the distribution patterns of scale size in relation to color pattern elements on the hindwings of the peacock pansy butterfly Junonia almana, together with other nymphalid butterflies, Vanessa indica and Danaus chrysippus. In these species, we observed a general decrease in scale size from the basal to the distal areas, although the size gradient was small in D. chrysippus. Scales of dark color in color pattern elements, including eyespot black rings, parafocal elements, and submarginal bands, were larger than those of their surroundings. Within an eyespot, the largest scales were found at the focal white area, although there were exceptional cases. Similarly, ectopic eyespots that were induced by physical damage on the J. almana background area had larger scales than in the surrounding area. These results are consistent with the previous finding that scale color and size coordinate to form color pattern elements. We propose a ploidy hypothesis to explain the color-size relationship in which the putative morphogenic signal induces the polyploidization (genome amplification) of immature scale cells and that the degrees of ploidy (gene dosage) determine scale color and scale size simultaneously in butterfly wings. PMID:26654884

  2. Assessing risk based on uncertain avalanche activity patterns

    NASA Astrophysics Data System (ADS)

    Zeidler, Antonia; Fromm, Reinhard

    2015-04-01

    Avalanches may affect critical infrastructure and may cause great economic losses. The planning horizon of infrastructures, e.g. hydropower generation facilities, reaches well into the future. Based on the results of previous studies on the effect of changing meteorological parameters (precipitation, temperature) and the effect on avalanche activity we assume that there will be a change of the risk pattern in future. The decision makers need to understand what the future might bring to best formulate their mitigation strategies. Therefore, we explore a commercial risk software to calculate risk for the coming years that might help in decision processes. The software @risk, is known to many larger companies, and therefore we explore its capabilities to include avalanche risk simulations in order to guarantee a comparability of different risks. In a first step, we develop a model for a hydropower generation facility that reflects the problem of changing avalanche activity patterns in future by selecting relevant input parameters and assigning likely probability distributions. The uncertain input variables include the probability of avalanches affecting an object, the vulnerability of an object, the expected costs for repairing the object and the expected cost due to interruption. The crux is to find the distribution that best represents the input variables under changing meteorological conditions. Our focus is on including the uncertain probability of avalanches based on the analysis of past avalanche data and expert knowledge. In order to explore different likely outcomes we base the analysis on three different climate scenarios (likely, worst case, baseline). For some variables, it is possible to fit a distribution to historical data, whereas in cases where the past dataset is insufficient or not available the software allows to select from over 30 different distribution types. The Monte Carlo simulation uses the probability distribution of uncertain variables

  3. Mouse Visual Neocortex Supports Multiple Stereotyped Patterns of Microcircuit Activity

    PubMed Central

    Sadovsky, Alexander J.

    2014-01-01

    Spiking correlations between neocortical neurons provide insight into the underlying synaptic connectivity that defines cortical microcircuitry. Here, using two-photon calcium fluorescence imaging, we observed the simultaneous dynamics of hundreds of neurons in slices of mouse primary visual cortex (V1). Consistent with a balance of excitation and inhibition, V1 dynamics were characterized by a linear scaling between firing rate and circuit size. Using lagged firing correlations between neurons, we generated functional wiring diagrams to evaluate the topological features of V1 microcircuitry. We found that circuit connectivity exhibited both cyclic graph motifs, indicating recurrent wiring, and acyclic graph motifs, indicating feedforward wiring. After overlaying the functional wiring diagrams onto the imaged field of view, we found properties consistent with Rentian scaling: wiring diagrams were topologically efficient because they minimized wiring with a modular architecture. Within single imaged fields of view, V1 contained multiple discrete circuits that were overlapping and highly interdigitated but were still distinct from one another. The majority of neurons that were shared between circuits displayed peri-event spiking activity whose timing was specific to the active circuit, whereas spike times for a smaller percentage of neurons were invariant to circuit identity. These data provide evidence that V1 microcircuitry exhibits balanced dynamics, is efficiently arranged in anatomical space, and is capable of supporting a diversity of multineuron spike firing patterns from overlapping sets of neurons. PMID:24899701

  4. The Influence of Relational Knowledge and Executive Function on Preschoolers' Repeating Pattern Knowledge

    ERIC Educational Resources Information Center

    Miller, Michael R.; Rittle-Johnson, Bethany; Loehr, Abbey M.; Fyfe, Emily R.

    2016-01-01

    Children's knowledge of repeating patterns (e.g., ABBABB) is a central component of early mathematics, but the developmental mechanisms underlying this knowledge are currently unknown. We sought clarity on the importance of relational knowledge and executive function (EF) to preschoolers' understanding of repeating patterns. One hundred…

  5. Patterns of Adolescents' Beliefs about Fighting and Their Relation to Behavior and Risk Factors for Aggression

    ERIC Educational Resources Information Center

    Farrell, Albert D.; Bettencourt, Amie; Mays, Sally; Kramer, Alison; Sullivan, Terri; Kliewer, Wendy

    2012-01-01

    This study examined adolescents' patterns of beliefs about aggression, and how these patterns relate to aggressive and prosocial behavior, and to risk factors associated with aggression. A sample of 477 sixth graders from two urban schools and a school in a nearby county completed measures of beliefs, behavior, and individual, peer and parental…

  6. Increased Vulnerability to Pattern-Related Visual Stress in Myalgic Encephalomyelitis.

    PubMed

    Wilson, Rachel L; Paterson, Kevin B; Hutchinson, Claire V

    2015-12-01

    The objective of this study was to determine vulnerability to pattern-related visual stress in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). A total of 20 ME/CFS patients and 20 matched (age, gender) controls were recruited to the study. Pattern-related visual stress was determined using the Pattern Glare Test. Participants viewed three patterns, the spatial frequencies (SF) of which were 0.3 (low-SF), 2.3 (mid-SF), and 9.4 (high-SF) cycles per degree (c/deg). They reported the number of distortions they experienced when viewing each pattern. ME/CFS patients exhibited significantly higher pattern glare scores than controls for the mid-SF pattern. Mid-high SF differences were also significantly higher in patients than controls. These findings provide evidence of altered visual perception in ME/CFS. Pattern-related visual stress may represent an identifiable clinical feature of ME/CFS that will prove useful in its diagnosis. However, further research is required to establish if these symptoms reflect ME/CFS-related changes in the functioning of sensory neural pathways. PMID:26562880

  7. Breathing pattern--gas exchange relation and acute effect of almitrine in severe chronic airflow obstruction.

    PubMed

    Damato, S; Bellone, A; Castelli, T; Mendoza, M; Daniele, R

    1988-01-01

    Using a double-blind cross-over design, a single oral dose of 100 mg almitrine bismethylate and placebo were administered to 7 patients with chronic airflow limitation. In all patients, arterial blood gases at rest, ventilation and breathing pattern at rest and on exercise were measured before and 3 h after administration. Ventilation increased and PaCO2 decreased after almitrine; the mean PaO2 increase was statistically significant after active drug but the value increased more when tidal volume increased. It is concluded that in man the well-documented improvement in the V/Q relationship after almitrine is in part related to a pure ventilatory effect though the possibility of increasing ventilation by mainly increasing tidal volume. PMID:2907669

  8. Relations between Fathers’ and Mothers’ Infant Engagement Patterns in Dual-Earner Families and Toddler Competence

    PubMed Central

    Lang, Sarah N.; Schoppe-Sullivan, Sarah J.; Kotila, Letitia E.; Feng, Xin; Dush, Claire M. Kamp; Johnson, Susan C.

    2015-01-01

    This study examined the trajectories of time new fathers and mothers in dual-earner families (N = 178) reported spending in developmentally appropriate positive engagement activities over the first 9 months of their child's life on both work and non-workdays. We also explored how paternal and maternal engagement patterns in infancy were associated with children's later social-emotional competence during toddlerhood (M = 25 months). Utilizing latent growth models, we found that, compared with mothers, fathers spent significantly less time engaging with their infants; however, both parents increased their engagement over time at relatively the same rate. Fathers’ rate of increase over time and mothers’ initial starting point of engagement on non-workdays were associated with toddlers’ attention and mastery motivation. Findings are discussed with regards to what they mean for dual-earner couples and fathers’ investment in their offspring, highlighting what they may imply about the second demographic transition and family functioning. PMID:26257454

  9. Stochastically Gating Ion Channels Enable Patterned Spike Firing through Activity-Dependent Modulation of Spike Probability

    PubMed Central

    Dudman, Joshua T.; Nolan, Matthew F.

    2009-01-01

    The transformation of synaptic input into patterns of spike output is a fundamental operation that is determined by the particular complement of ion channels that a neuron expresses. Although it is well established that individual ion channel proteins make stochastic transitions between conducting and non-conducting states, most models of synaptic integration are deterministic, and relatively little is known about the functional consequences of interactions between stochastically gating ion channels. Here, we show that a model of stellate neurons from layer II of the medial entorhinal cortex implemented with either stochastic or deterministically gating ion channels can reproduce the resting membrane properties of stellate neurons, but only the stochastic version of the model can fully account for perithreshold membrane potential fluctuations and clustered patterns of spike output that are recorded from stellate neurons during depolarized states. We demonstrate that the stochastic model implements an example of a general mechanism for patterning of neuronal output through activity-dependent changes in the probability of spike firing. Unlike deterministic mechanisms that generate spike patterns through slow changes in the state of model parameters, this general stochastic mechanism does not require retention of information beyond the duration of a single spike and its associated afterhyperpolarization. Instead, clustered patterns of spikes emerge in the stochastic model of stellate neurons as a result of a transient increase in firing probability driven by activation of HCN channels during recovery from the spike afterhyperpolarization. Using this model, we infer conditions in which stochastic ion channel gating may influence firing patterns in vivo and predict consequences of modifications of HCN channel function for in vivo firing patterns. PMID:19214199

  10. LEISURE ACTIVITY PATTERNS AND THEIR ASSOCIATIONS WITH OVERWEIGHT: A PROSPECTIVE STUDY AMONG ADOLESCENTS

    PubMed Central

    Lajunen, Hanna-Reetta; Keski-Rahkonen, Anna; Pulkkinen, Lea; Rose, Richard J.; Rissanen, Aila; Kaprio, Jaakko

    2009-01-01

    We examined longitudinal associations between individual leisure activities (television viewing, video viewing, computer games, listening to music, board games, musical instrument playing, reading, arts, crafts, socializing, clubs or scouts, sports, outdoor activities) and being overweight using logistic regression and latent class analysis in a cohort of Finnish twins responding to self-report questionnaires at 11–12 (N=5184), 14, and 17 years. We also studied activity patterns (“Active and sociable”, “Active but less sociable”, “Passive but sociable”, “Passive and solitary”) thought to represent different lifestyles. Among boys, activity patterns did not predict becoming overweight, but sports and playing an instrument reduced the risk and arts and listening to music increased it. Among girls, few individual leisure activities predicted becoming overweight. However, girls in the “Passive and solitary” cluster carried the greatest risk of becoming overweight in late adolescence. Studying leisure activities related to overweight may help focus specific interventions on high risk groups. PMID:19345989

  11. Quasicrystals and the Penrose Patterns: A Geometric Activity with a Scientific Application.

    ERIC Educational Resources Information Center

    Clason, Robert; And Others

    1993-01-01

    Penrose tile patterns are created using regular pentagon-based rhombi. Provides instructions for assembling Penrose patterns, plus activities for secondary school students and preservice elementary teachers. Compares the two-dimensional process of placing pattern blocks to form Penrose patterns to the symmetries of crystals formed in nature.…

  12. Predicting brain activation patterns associated with individual lexical concepts based on five sensory-motor attributes.

    PubMed

    Fernandino, Leonardo; Humphries, Colin J; Seidenberg, Mark S; Gross, William L; Conant, Lisa L; Binder, Jeffrey R

    2015-09-01

    While major advances have been made in uncovering the neural processes underlying perceptual representations, our grasp of how the brain gives rise to conceptual knowledge remains relatively poor. Recent work has provided strong evidence that concepts rely, at least in part, on the same sensory and motor neural systems through which they were acquired, but it is still unclear whether the neural code for concept representation uses information about sensory-motor features to discriminate between concepts. In the present study, we investigate this question by asking whether an encoding model based on five semantic attributes directly related to sensory-motor experience - sound, color, visual motion, shape, and manipulation - can successfully predict patterns of brain activation elicited by individual lexical concepts. We collected ratings on the relevance of these five attributes to the meaning of 820 words, and used these ratings as predictors in a multiple regression model of the fMRI signal associated with the words in a separate group of participants. The five resulting activation maps were then combined by linear summation to predict the distributed activation pattern elicited by a novel set of 80 test words. The encoding model predicted the activation patterns elicited by the test words significantly better than chance. As expected, prediction was successful for concrete but not for abstract concepts. Comparisons between encoding models based on different combinations of attributes indicate that all five attributes contribute to the representation of concrete concepts. Consistent with embodied theories of semantics, these results show, for the first time, that the distributed activation pattern associated with a concept combines information about different sensory-motor attributes according to their respective relevance. Future research should investigate how additional features of phenomenal experience contribute to the neural representation of conceptual

  13. De Winter Electrocardiographic Pattern Related with a Non-Left Anterior Descending Coronary Artery Occlusion.

    PubMed

    Montero Cabezas, José M; Karalis, Ioannis; Schalij, Martin J

    2016-09-01

    The electrocardiographic pattern consisting of ST-segment depression and hyperacute T waves in patients with acute chest pain, known as "De Winter pattern," has been related with the occlusion of the proximal left anterior descending artery (LAD). The association of these findings with the involvement of a different coronary artery has not been described. We present a 53-year-old patient with an occlusion of the first diagonal branch and an electrocardiogram showing a "De Winter pattern." The reported case demonstrates that "De Winter pattern" is not exclusively associated with the occlusion of the proximal segment of the LAD. PMID:27592618

  14. Predicting variations of perceptual performance across individuals from neural activity using pattern classifiers.

    PubMed

    Das, Koel; Giesbrecht, Barry; Eckstein, Miguel P

    2010-07-15

    Within the past decade computational approaches adopted from the field of machine learning have provided neuroscientists with powerful new tools for analyzing neural data. For instance, previous studies have applied pattern classification algorithms to electroencephalography data to predict the category of presented visual stimuli, human observer decision choices and task difficulty. Here, we quantitatively compare the ability of pattern classifiers and three ERP metrics (peak amplitude, mean amplitude, and onset latency of the face-selective N170) to predict variations across individuals' behavioral performance in a difficult perceptual task identifying images of faces and cars embedded in noise. We investigate three different pattern classifiers (Classwise Principal Component Analysis, CPCA; Linear Discriminant Analysis, LDA; and Support Vector Machine, SVM), five training methods differing in the selection of training data sets and three analyses procedures for the ERP measures. We show that all three pattern classifier algorithms surpass traditional ERP measurements in their ability to predict individual differences in performance. Although the differences across pattern classifiers were not large, the CPCA method with training data sets restricted to EEG activity for trials in which observers expressed high confidence about their decisions performed the highest at predicting perceptual performance of observers. We also show that the neural activity predicting the performance across individuals was distributed through time starting at 120ms, and unlike the face-selective ERP response, sustained for more than 400ms after stimulus presentation, indicating that both early and late components contain information correlated with observers' behavioral performance. Together, our results further demonstrate the potential of pattern classifiers compared to more traditional ERP techniques as an analysis tool for modeling spatiotemporal dynamics of the human brain and

  15. Multiple active forms of thrombin. IV. Relative activities of meizothrombins

    SciTech Connect

    Doyle, M.F.; Mann, K.G. )

    1990-06-25

    The prothrombin activation intermediates meizothrombin and meizothrombin(desF1) (meizothrombin that has been autoproteolyzed to remove fragment 1) have been obtained in a relatively pure, active form with minimal autolysis, making them suitable for enzymatic characterization. When compared at equimolar concentrations, alpha-thrombin, fragment 1.2+ alpha-thrombin, meizothrombin(desF1), and meizothrombin have approximately 100, 100, 10, and 1% activity, respectively, toward the macromolecular substrates factor V, fibrinogen, and platelets. The difference in activity of these four enzymes cannot be attributed to alterations in the catalytic triad, as all four enzymes have nearly identical catalytic efficiency toward the chromogenic substrate S2238. Further, the ability of meizothrombin and meizothrombin(desF1) to activate protein C was 75% of the activity exhibited by alpha-thrombin or fragment 1.2+ alpha-thrombin. All four enzymes bind to thrombomodulin, as judged by the enhanced rate of protein C activation upon preincubation of the enzymes with thrombomodulin. The extent of rate enhancement varied, with meizothrombin/thrombomodulin exhibiting only 50% of the alpha-thrombin/thrombomodulin rate. This difference in rate is not due to a decreased affinity of the meizothrombin for thrombomodulin since the apparent dissociation constants for the alpha-thrombin-thrombomodulin complex and the meizothrombin-thrombomodulin complex are virtually identical. The difference in the observed rate is due in part to the higher Km for protein C exhibited by the meizothrombin-thrombomodulin complex. Incubation of the thrombomodulin-enzyme complex with phospholipid vesicles caused an increase in the protein C activation rates. The kinetic constants for protein C activation in the presence of phospholipid are virtually identical for these enzyme-thrombomodulin complexes.

  16. Evolutionary patterns of proteinase activity in attine ant fungus gardens

    PubMed Central

    2011-01-01

    Background Attine ants live in symbiosis with a basidiomycetous fungus that they rear on a substrate of plant material. This indirect herbivory implies that the symbiosis is likely to be nitrogen deprived, so that specific mechanisms may have evolved to enhance protein availability. We therefore hypothesized that fungal proteinase activity may have been under selection for efficiency and that different classes of proteinases might be involved. Results We determined proteinase activity profiles across a wide pH range for fungus gardens of 14 Panamanian species of fungus-growing ants, representing eight genera. We mapped these activity profiles on an independently obtained molecular phylogeny of the symbionts and show that total proteinase activity in lower attine symbionts peaks at ca. pH 6. The higher attine symbionts that have no known free-living relatives had much higher proteinase activities than the lower attine symbionts. Their total in vitro proteinase activity peaked at pH values around 5, which is close to the pH that the ants maintain in their fungus gardens, suggesting that the pH optimum of fungal proteinases may have changed after the irreversible domestication of evolutionary more derived fungal symbionts. This notion is also supported by buffering capacities of fungus gardens at pH 5.2 being remarkably high, and suggests that the fungal symbiont actively helps to maintain garden acidity at this specific level. Metalloproteinases dominated the activity profiles of lower attine gardens and may thus represent the ancestral type of proteinase production, whereas serine proteinase activity dominated the activity profiles of the higher attine gardens reared by Trachymyrmex and Sericomyrmex, suggesting that there may be trade-offs in the production of these enzyme classes. Remarkably, the single symbiont that is shared by species of the crown group of Atta and Acromyrmex leaf-cutting ants mostly showed metalloproteinase activity, suggesting that recurrent

  17. Top 10 Research Questions Related to Physical Activity in Preschool Children

    ERIC Educational Resources Information Center

    Pate, Russell R.; O'Neill, Jennifer R.; Brown, William H.; McIver, Kerry L.; Howie, Erin K.; Dowda, Marsha

    2013-01-01

    The purpose of this article was to highlight important research needs related to physical activity in 3-to 5-year-old children. We identified research needs in 3 major categories: health effects, patterns of physical activity, and interventions and policies. The top research needs include identifying the health effects of physical activity, the…

  18. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    PubMed Central

    2012-01-01

    Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae), wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow) and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i) 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii) four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4)-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily accessible hemicellulose

  19. Patterns of Communicative Interaction between a Child with Severe Speech and Physical Impairments and Her Caregiver during a Mealtime Activity

    ERIC Educational Resources Information Center

    Ferm, Ulrika; Ahlsen, Elisabeth; Bjorck-Akesson, Eva

    2012-01-01

    Background: Interaction between caregivers and children with severe impairments is closely related to the demands of daily activities. This study examines the relationship between interaction and the routine mealtime activity at home. Method: Patterns of interaction between a child (aged 6 years and 6 months) with severe speech and physical…

  20. Mother-Child Attachment Patterns and Different Types of Anxiety Symptoms: Is There Specificity of Relations?

    ERIC Educational Resources Information Center

    Brumariu, Laura E.; Kerns, Kathryn A.

    2010-01-01

    The purpose of this study was to test Manassis' proposal (Child-parent relations: Attachment and anxiety disorders, 255-272, 2001) that attachment patterns (secure, ambivalent, avoidant, and disorganized) may relate to different types of anxiety symptoms, and that behavioral inhibition may moderate these relations. Using a story stem interview to…

  1. Effects of Individual Health Topic Familiarity on Activity Patterns During Health Information Searches

    PubMed Central

    Moriyama, Koichi; Fukui, Ken–ichi; Numao, Masayuki

    2015-01-01

    Background Non-medical professionals (consumers) are increasingly using the Internet to support their health information needs. However, the cognitive effort required to perform health information searches is affected by the consumer’s familiarity with health topics. Consumers may have different levels of familiarity with individual health topics. This variation in familiarity may cause misunderstandings because the information presented by search engines may not be understood correctly by the consumers. Objective As a first step toward the improvement of the health information search process, we aimed to examine the effects of health topic familiarity on health information search behaviors by identifying the common search activity patterns exhibited by groups of consumers with different levels of familiarity. Methods Each participant completed a health terminology familiarity questionnaire and health information search tasks. The responses to the familiarity questionnaire were used to grade the familiarity of participants with predefined health topics. The search task data were transcribed into a sequence of search activities using a coding scheme. A computational model was constructed from the sequence data using a Markov chain model to identify the common search patterns in each familiarity group. Results Forty participants were classified into L1 (not familiar), L2 (somewhat familiar), and L3 (familiar) groups based on their questionnaire responses. They had different levels of familiarity with four health topics. The video data obtained from all of the participants were transcribed into 4595 search activities (mean 28.7, SD 23.27 per session). The most frequent search activities and transitions in all the familiarity groups were related to evaluations of the relevancy of selected web pages in the retrieval results. However, the next most frequent transitions differed in each group and a chi-squared test confirmed this finding (P<.001). Next, according to the

  2. Dietary Patterns and Cardiovascular Disease-Related Risks in Chinese Older Adults

    PubMed Central

    Sun, Jing; Buys, Nicholas; Shen, Shuying

    2013-01-01

    Studies of Western populations demonstrate a relationship between dietary patterns and cardiovascular-related risk factors. Similar research regarding Chinese populations is limited. This study explored the dietary patterns of Chinese older adults and their association with cardiovascular-related risk factors, including hypertension, obesity, and metabolic syndrome. Data were collected using a 34-item Chinese food frequency questionnaire from 750 randomly selected older adults aged 50–88 who participated in the study in 2012. Factor analysis revealed four dietary patterns: a “traditional food pattern,” consisting of vegetable, fruit, rice, pork, and fish; a “fast and processed food pattern” consisting of fast or processed food products, sugar, and confectionery; a “soybean, grain, and flour food pattern”; and a “dairy, animal liver, and other animal food pattern.” These patterns explained 17.48, 9.52, 5.51, and 4.80% of the variances in food intake, respectively. This study suggests that specific dietary patterns are evident in Chinese older adults. Moderate intake of “traditional Chinese food” is associated with decreased blood pressure and cholesterol level. A dietary pattern rich in soybeans, grains, potatoes, and flour is associated with reduced metabolic factors including reduced triglycerides, fasting glucose, waist circumference, and waist–hip ratio, and a high level of dairy, animal liver, and other animal intake food pattern is associated with increased level of Body Mass Index. In conclusion, this study revealed identifiable dietary patterns among Chinese older adults that are significantly related to blood pressure and metabolic biomarkers. Further study using prospective cohort or intervention study should be used to confirm the association between dietary patterns and blood pressure and metabolic factors. PMID:24350217

  3. Altered rest-activity patterns evolve via circadian independent mechanisms in cave adapted balitorid loaches.

    PubMed

    Duboué, Erik R; Borowsky, Richard L

    2012-01-01

    Circadian rhythms and rest homeostasis are independent processes, each regulating important components of rest-activity patterns. Evolutionarily, the two are distinct from one another; total rest time is maintained unaffected even when circadian pacemaker cells are ablated. Throughout the animal kingdom, there exists a huge variation in rest-activity patterns, yet it is unclear how these behaviors have evolved. Here we show that four species of balitorid cavefish have greatly reduced rest times in comparison to rest times of their surface relatives. All four cave species retained biological rhythmicity, and in three of the four there is a pronounced 24-hour rhythm; in the fourth there is an altered rhythmicity of 38-40 hours. Thus, consistent changes in total rest have evolved in these species independent of circadian rhythmicity. Taken together, our data suggest that consistent reduction in total rest times were accomplished evolutionarily through alterations in rest homeostasis. PMID:22348026

  4. Large-scale circulation patterns and related rainfall in the Amazon Basin: a neuronal networks approach

    NASA Astrophysics Data System (ADS)

    Espinoza, Jhan Carlo; Lengaigne, Matthieu; Ronchail, Josyane; Janicot, Serge

    2012-01-01

    This study describes the main circulation patterns (CP) in the Amazonian Basin over the 1975-2002 period and their relationship with rainfall variability. CPs in the Amazonian Basin have been computed for each season from the ERA-40 daily 850 hPa winds using an approach combining artificial neural network (Self Organizing Maps) and Hierarchical Ascendant Classification. A 6 to 8 cluster solutions (depending on the season considered) is shown to yield an integrated view of the complex regional circulation variability. For austral fall, winter and spring the temporal evolution between the different CPs shows a clear tendency to describe a cycle, with southern wind anomalies and their convergence with the trade winds progressing northward from the La Plata Basin to the Amazon Basin. This sequence is strongly related to eastward moving extra tropical perturbations and their incursion toward low latitude that modulate the geopotential and winds over South America and its adjoining oceans. During Austral summer, CPs are less spatially and temporally organized compared to other seasons, principally due to weaker extra tropical perturbations and more frequent shallow low situations. Each of these CPs is shown to be associated with coherent northward moving regional rainfall patterns (both in in situ data and ERA-40 reanalysis) and convective activity. However, our results reveals that precipitation variability is better reproduced by ERA-40 in the southern part of the Amazonian Basin than in the northern part, where rainfall variability is likely to be more constrained by local and subdaily processes (e.g. squall lines) that could be misrepresented in the reanalysis dataset. This analysis clearly illustrates the existing connections between the southern and northern part of the Amazonian Basin in terms of regional circulation/rainfall patterns. The identification of these CPs provide useful information to understand local rainfall variability and could hence be used to

  5. Guiding catalytically active particles with chemically patterned surfaces

    NASA Astrophysics Data System (ADS)

    Uspal, William; Popescu, Mihail; Dietrich, Siegfried; Tasinkevych, Mykola

    Catalytically active Janus particles in solution create gradients in the chemical composition of the solution along their surfaces, as well as along any nearby container walls. The former leads to self-phoresis, while the latter gives rise to chemi-osmosis, providing an additional contribution to self-motility. Chemi-osmosis strongly depends on the molecular interactions between the diffusing chemical species and the wall. We show analytically, using an approximate ``point-particle'' approach, that by chemically patterning a planar substrate (e.g., by adsorbing two different materials) one can direct the motion of Janus particles: the induced chemi-osmotic flows can cause particles to either ``dock'' at a chemical step between the two materials, or to follow a chemical stripe. These theoretical predictions are confirmed by full numerical calculations. Generically, docking occurs for particles which tend to move away from their catalytic caps, while stripe-following occurs in the opposite case. Our analysis reveals the physical mechanisms governing this behavior.

  6. Gene Expression Patterns Related to Vascular Invasion and Aggressive Features in Endometrial Cancer

    PubMed Central

    Mannelqvist, Monica; Stefansson, Ingunn M.; Bredholt, Geir; Hellem Bø, Trond; Øyan, Anne M.; Jonassen, Inge; Kalland, Karl-Henning; Salvesen, Helga B.; Akslen, Lars A.

    2011-01-01

    The presence of tumor cells entering vascular channels is a prognostic marker for many cancers, including endometrial carcinoma. Vascular invasion is considered to be an early step in the metastatic process and important for the progress of malignant tumors. Here, we investigated the gene expression patterns related to vascular involvement in 57 primary endometrial cancers, using DNA microarray and quantitative PCR techniques. A vascular invasion signature of 18 genes was significantly associated with patient survival and clinicopathological phenotype. Vascular involvement was also related to gene sets for epithelial-mesenchymal transition, wound response, endothelial cells, and vascular endothelial growth factor (VEGF) activity. With immunohistochemical validation, both collagen 8 and matrix metalloproteinase 3 (MMP3) were associated with vascular invasion, whereas ANGPTL4 and IL-8 were associated with patient survival. Our findings indicate that vascular involvement within primary tumors is associated with gene expression profiles related to angiogenesis and epithelial-mesenchymal transition. These data could contribute to an improved understanding of potential targets for metastatic spread and may provide clinically important information for better management of endometrial cancer. PMID:21281818

  7. Time-budgets and activity patterns of captive Sunda pangolins (Manis javanica).

    PubMed

    Challender, Daniel W S; Thai, Nguyen Van; Jones, Martin; May, Les

    2012-01-01

    This is the first assessment of Manis javanica behavior in captivity. The aim of the investigation was to assess behavior in order to suggest ways of improving captive care and management of the species. This was undertaken by constructing time-budgets and activity patterns and identifying any abnormal repetitive behavior (ARB) exhibited. Scan and focal animal sampling were implemented in observations of seven subjects. Analyses detailed idiosyncrasies in how subjects partitioned their active time. Peak activity occurred between 18:00 and 21:00 hr. Two ARBs, clawing and pacing, were identified and the cessation of clawing in one subject was possible by modifying its enclosure. Stress-related behavior, understood to be related to several factors, means maintaining this species in captivity remains problematic. Recommendations are made pertaining to husbandry, captive management, and future research. PMID:21360581

  8. Modular organization of the multipartite central pattern generator for turtle rostral scratch: knee-related interneurons during deletions.

    PubMed

    Stein, Paul S G; Daniels-McQueen, Susan; Lai, Jessica; Liu, Z; Corman, Tanya S

    2016-06-01

    Central pattern generators (CPGs) are neuronal networks in the spinal cord that generate rhythmic patterns of motor activity in the absence of movement-related sensory feedback. For many vertebrate rhythmic behaviors, CPGs generate normal patterns of motor neuron activities as well as variations of the normal patterns, termed deletions, in which bursts in one or more motor nerves are absent from one or more cycles of the rhythm. Prior work with hip-extensor deletions during turtle rostral scratch supports hypotheses of hip-extensor interneurons in a hip-extensor module and of hip-flexor interneurons in a hip-flexor module. We present here single-unit interneuronal recording data that support hypotheses of knee-extensor interneurons in a knee-extensor module and of knee-flexor interneurons in a knee-flexor module. Members of knee-related modules are not members of hip-related modules and vice versa. These results in turtle provide experimental support at the single-unit interneuronal level for the organizational concept that the rostral-scratch CPG for the turtle hindlimb is multipartite, that is, composed of more than two modules. This work, when combined with experimental and computational work in other vertebrates, does not support the classical view that the vertebrate limb CPG is bipartite with only two modules, one controlling all the flexors of the limb and the other controlling all the extensors of the limb. Instead, these results support the general principle that spinal CPGs are multipartite. PMID:27030737

  9. Differences in the Efficiency of Pattern Encoding in Relation to Autistic-Like Traits: An Event-Related Potential Study

    ERIC Educational Resources Information Center

    Takahashi, Junichi; Yasunaga, Daichi; Gyoba, Jiro

    2014-01-01

    We examined the effects of complexity on the efficiency of pattern encoding in the general population differing on autism-spectrum quotient (AQ) scores. We compared brain activity (electroencephalography) during a same-different task for High and Low AQ groups. The task was composed of identical comparison and categorical comparison (CC)…

  10. Automatic generation of primary sequence patterns from sets of related protein sequences.

    PubMed

    Smith, R F; Smith, T F

    1990-01-01

    We have developed a computer algorithm that can extract the pattern of conserved primary sequence elements common to all members of a homologous protein family. The method involves clustering the pairwise similarity scores among a set of related sequences to generate a binary dendrogram (tree). The tree is then reduced in a stepwise manner by progressively replacing the node connecting the two most similar termini by one common pattern until only a single common "root" pattern remains. A pattern is generated at a node by (i) performing a local optimal alignment on the sequence/pattern pair connected by the node with the use of an extended dynamic programming algorithm and then (ii) constructing a single common pattern from this alignment with a nested hierarchy of amino acid classes to identify the minimal inclusive amino acid class covering each paired set of elements in the alignment. Gaps within an alignment are created and/or extended using a "pay once" gap penalty rule, and gapped positions are converted into gap characters that function as 0 or 1 amino acid of any type during subsequent alignment. This method has been used to generate a library of covering patterns for homologous families in the National Biomedical Research Foundation/Protein Identification Resource protein sequence data base. We show that a covering pattern can be more diagnostic for sequence family membership than any of the individual sequences used to construct the pattern. PMID:2296575

  11. Documenting Western Burrowing Owl Reproduction and Activity Patterns Using Motion-Activated Cameras

    SciTech Connect

    Hall, Derek B.; Greger, Paul D.

    2014-08-01

    We used motion-activated cameras to monitor the reproduction and patterns of activity of the Burrowing Owl (Athene cunicularia) above ground at 45 burrows in south-central Nevada during the breeding seasons of 1999, 2000, 2001, and 2005. The 37 broods, encompassing 180 young, raised over the four years represented an average of 4.9 young per successful breeding pair. Young and adult owls were detected at the burrow entrance at all times of the day and night, but adults were detected more frequently during afternoon/early evening than were young. Motion-activated cameras require less effort to implement than other techniques. Limitations include photographing only a small percentage of owl activity at the burrow; not detecting the actual number of eggs, young, or number fledged; and not being able to track individual owls over time. Further work is also necessary to compare the accuracy of productivity estimates generated from motion-activated cameras with other techniques.

  12. A bacterial tyrosine phosphatase inhibits plant pattern recognition receptor activation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perception of pathogen-associated molecular patterns (PAMPs) by surface-localised pattern-recognition receptors (PRRs) is a key component of plant innate immunity. Most known plant PRRs are receptor kinases and initiation of PAMP-triggered immunity (PTI) signalling requires phosphorylation of the PR...

  13. Anglo- and Mexican-American preschoolers at home and at recess: activity patterns and environmental influences.

    PubMed

    McKenzie, T L; Sallis, J F; Nader, P R; Broyles, S L; Nelson, J A

    1992-06-01

    Habitual physical activity in children is related to physical fitness and appears to mediate cardiovascular disease (CVD) risk factors. We studied the physical activity patterns and associated variables of a large bi-ethnic cohort of 4-year-old children from low to middle socioeconomic families. Trained observers coded the behavior of 351 children (150 Anglo-American, 201 Mexican-American; 182 boys, 169 girls) during two 60-minute home visits and two unstructured recesses lasting up to 30 minutes each at 63 different preschools. Findings indicated that although children were much less active at home, there were low but significant correlations between their activity patterns at home and during recess (r = .13). Children who had activity-promoting toys at home also tended to have them available during preschool recess (r = .20). Ethnic differences were evident for both activity and environmental variables. Mexican-American children were less active than Anglo children at home (p less than .002) and during recess (p less than .03), thus adding to the adult literature that has found Mexican-Americans to be less active than Anglos, and supporting to the notion that physical activity life-style habits may be established in early childhood. In both settings, Mexican-American children spent more time in presence of adults (home, p less than .04; recess, p less than .03) and had access to fewer active toys (home, p less than .001; recess, p less than .05). Gender differences were also evident for both activity and environmental variables.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1613112

  14. Hidden pattern discovery on epileptic EEG with 1-D local binary patterns and epileptic seizures detection by grey relational analysis.

    PubMed

    Kaya, Yılmaz

    2015-09-01

    This paper proposes a novel approach to detect epilepsy seizures by using Electroencephalography (EEG), which is one of the most common methods for the diagnosis of epilepsy, based on 1-Dimension Local Binary Pattern (1D-LBP) and grey relational analysis (GRA) methods. The main aim of this paper is to evaluate and validate a novel approach, which is a computer-based quantitative EEG analyzing method and based on grey systems, aimed to help decision-maker. In this study, 1D-LBP, which utilizes all data points, was employed for extracting features in raw EEG signals, Fisher score (FS) was employed to select the representative features, which can also be determined as hidden patterns. Additionally, GRA is performed to classify EEG signals through these Fisher scored features. The experimental results of the proposed approach, which was employed in a public dataset for validation, showed that it has a high accuracy in identifying epileptic EEG signals. For various combinations of epileptic EEG, such as A-E, B-E, C-E, D-E, and A-D clusters, 100, 96, 100, 99.00 and 100% were achieved, respectively. Also, this work presents an attempt to develop a new general-purpose hidden pattern determination scheme, which can be utilized for different categories of time-varying signals. PMID:26206400

  15. Groundwater flow pattern and related environmental phenomena in complex geologic setting based on integrated model construction

    NASA Astrophysics Data System (ADS)

    Tóth, Ádám; Havril, Tímea; Simon, Szilvia; Galsa, Attila; Monteiro Santos, Fernando A.; Müller, Imre; Mádl-Szőnyi, Judit

    2016-08-01

    Groundwater flow, driven, controlled and determined by topography, geology and climate, is responsible for several natural surface manifestations and affected by anthropogenic processes. Therefore, flowing groundwater can be regarded as an environmental agent. Numerical simulation of groundwater flow could reveal the flow pattern and explain the observed features. In complex geologic framework, where the geologic-hydrogeologic knowledge is limited, the groundwater flow model could not be constructed based solely on borehole data, but geophysical information could aid the model building. The integrated model construction was presented via the case study of the Tihany Peninsula, Hungary, with the aims of understanding the background and occurrence of groundwater-related environmental phenomena, such as wetlands, surface water-groundwater interaction, slope instability, and revealing the potential effect of anthropogenic activity and climate change. The hydrogeologic model was prepared on the basis of the compiled archive geophysical database and the results of recently performed geophysical measurements complemented with geologic-hydrogeologic data. Derivation of different electrostratigraphic units, revealing fracturing and detecting tectonic elements was achieved by systematically combined electromagnetic geophysical methods. The deduced information can be used as model input for groundwater flow simulation concerning hydrostratigraphy, geometry and boundary conditions. The results of numerical modelling were interpreted on the basis of gravity-driven regional groundwater flow concept and validated by field mapping of groundwater-related phenomena. The 3D model clarified the hydraulic behaviour of the formations, revealed the subsurface hydraulic connection between groundwater and wetlands and displayed the groundwater discharge pattern, as well. The position of wetlands, their vegetation type, discharge features and induced landslides were explained as

  16. Evolution of Muscle Activity Patterns Driving Motions of the Jaw and Hyoid during Chewing in Gnathostomes

    PubMed Central

    Konow, Nicolai; Herrel, Anthony; Ross, Callum F.; Williams, Susan H.; German, Rebecca Z.; Sanford, Christopher P. J.; Gintof, Chris

    2011-01-01

    Although chewing has been suggested to be a basal gnathostome trait retained in most major vertebrate lineages, it has not been studied broadly and comparatively across vertebrates. To redress this imbalance, we recorded EMG from muscles powering anteroposterior movement of the hyoid, and dorsoventral movement of the mandibular jaw during chewing. We compared muscle activity patterns (MAP) during chewing in jawed vertebrate taxa belonging to unrelated groups of basal bony fishes and artiodactyl mammals. Our aim was to outline the evolution of coordination in MAP. Comparisons of activity in muscles of the jaw and hyoid that power chewing in closely related artiodactyls using cross-correlation analyses identified reorganizations of jaw and hyoid MAP between herbivores and omnivores. EMG data from basal bony fishes revealed a tighter coordination of jaw and hyoid MAP during chewing than seen in artiodactyls. Across this broad phylogenetic range, there have been major structural reorganizations, including a reduction of the bony hyoid suspension, which is robust in fishes, to the acquisition in a mammalian ancestor of a muscle sling suspending the hyoid. These changes appear to be reflected in a shift in chewing MAP that occurred in an unidentified anamniote stem-lineage. This shift matches observations that, when compared with fishes, the pattern of hyoid motion in tetrapods is reversed and also time-shifted relative to the pattern of jaw movement. PMID:21705368

  17. [Relation between voice quality and pathological vibratory patterns using high-speed digital imaging].

    PubMed

    Miyaji, M; Iwamoto, Y; Oda, M; Niimi, S

    1999-03-01

    We analysed the vocal fold vibrations of 22 pathological larynges using a computer-assisted high-speed digital imaging technique. The parameters observed included symmetry, regularity, phase difference, glottal closure, amplitude, mucosal wave and periodicity difference. Voice quality was evaluated by a GRBAS system, and we examined the relation between vocal fold vibration patterns and voice quality. The intraexaminer correlation coefficient was high for the G, R and B scales. Vibratory patterns were classified according to the location of the lesion, severity of the disease, expiratory pressure and laryngeal modulation. Although there were no matches between a vocal fold vibratory pattern for one psychoacoustic impression of hoarseness, the characteristic vibratory patterns of these cases of R > or = 2.5 or diplophonia exhibited irregular glottal closure and periodicity differences. The characteristic vibratory pattern of vocal fry is a double or triple opening/closing phase, followed by a long closed phase. PMID:10226472

  18. Geometry and relative age of large patterned fractures in southern Acidalia Planitia, Mars

    NASA Technical Reports Server (NTRS)

    Borrello, Murray C.

    1987-01-01

    Extraordinary patterned fractures occur in Elysium, Utopia, and Acidalia Planitiae of Mars. Theories as to their origin range from permafrost patterning to tectonic fracturing. Recent studies indicate the patterned fractures may be a surface reflection of rough, buried terrane in which fracturing occurs as a result of differential compaction. The patterned terrane in the southern portion of the Acidalia region (MC4-SE, MC4-SC) is being studied to determine its age relative to other terranes and events, and to constrain models for the origin of the fractures. Fracturing in this area occurs between 5 and 25 degrees west longitude and 37 and 50 degrees north latitude. Many fracture patterns are roughly polygonal, with polygons ranging in size from approximately 11 to 32 km in diameter. Fracture traces range from the limit of resolution (10's of meters) to 35 km in length.

  19. Emergence of long-range correlations and bursty activity patterns in online communication

    NASA Astrophysics Data System (ADS)

    Panzarasa, Pietro; Bonaventura, Moreno

    2015-12-01

    Research has suggested that the activity occurring in a variety of social, economic, and technological systems exhibits long-range fluctuations in time. Pronounced levels of rapidly occurring events are typically observed over short periods of time, followed by long periods of inactivity. Relatively few studies, however, have shed light on the degree to which inhomogeneous temporal processes can be detected at, and emerge from, different levels of analysis. Here we investigate patterns of human activity within an online forum in which communication can be assessed at three intertwined levels: the micro level of the individual users; the meso level of discussion groups and continuous sessions; and the macro level of the whole system. To uncover the relation between different levels, we conduct a number of numerical simulations of a zero-crossing model in which users' behavior is constrained by progressively richer and more realistic rules of social interaction. Results indicate that, when users are solipsistic, their bursty behavior is not sufficient for generating heavy-tailed interevent time distributions at a higher level. However, when users are socially interdependent, the power spectra and interevent time distributions of the simulated and real forums are remarkably similar at all levels of analysis. Social interaction is responsible for the aggregation of multiple bursty activities at the micro level into an emergent bursty activity pattern at a higher level. We discuss the implications of the findings for an emergentist account of burstiness in complex systems.

  20. PATTERNS OF PHYSICAL ACTIVITY AMONG AMERICAN INDIAN CHILDREN: AN ASSESSMENT OF BARRIERS AND SUPPORT

    PubMed Central

    Thompson, Janice L.; Davis, Sally M.; Gittelsohn, Joel; Going, Scott; Becenti, Alberta; Metcalfe, Lauve; Stone, Elaine; Harnack, Lisa; Ring, Kim

    2016-01-01

    Estimates indicate that 10% to 50% of American Indian and non-Indian children in the U.S. are obese, defined as a body mass index ≥ 95th percentile of the NHANES II reference data. Pathways is a two-phase, multi-site study to develop and test a school-based obesity prevention program in American Indian schoolchildren in grades three through five. During Phase I feasibility prior to initiation of the Pathways trial, data were collected related to physical activity patterns, and the supports of, and barriers to, physical activity. Nine schools from communities representing six different tribal groups participated in this study. Multiple measures were used for data collection including direct observation, paired child interviews, and in-depth interviews and focus groups with adults. Students completed the self-administered Knowledge, Attitudes, and Behaviors (KAB) survey, and a Physical Activity Questionnaire (PAQ). Barriers to physical activity at schools included a lack of facilities, equipment, and trained staff persons for PE. Adults were not consistently active with their children, but they were highly supportive of their children’s activity level. Children reported a strong enjoyment of physical activity and strong peer support to be physically active. Weather conditions, safety concerns, and homework/chores were common barriers to physical activity reported by children and adult caregivers. The information was used to design culturally and age-appropriate, practical interventions including the five physical activity programs for schoolchildren in the Pathways study. PMID:11759094

  1. Patterns of physical activity among American Indian children: an assessment of barriers and support.

    PubMed

    Thompson, J L; Davis, S M; Gittelsohn, J; Going, S; Becenti, A; Metcalfe, L; Stone, E; Harnack, L; Ring, K

    2001-12-01

    Estimates indicate that 10% to 50% of American Indian and non-Indian children in the U.S. are obese, defined as a body mass index > or = 95th percentile of the NHANES II reference data. Pathways is a two-phase, multi-site study to develop and test a school-based obesity prevention program in American Indian schoolchildren in grades three through five. During Phase I feasibility prior to initiation of the Pathways trial, data were collected related to physical activity patterns, and the supports of, and barriers to, physical activity. Nine schools from communities representing six different tribal groups participated in this study. Multiple measures were used for data collection including direct observation, paired child interviews, and in-depth interviews and focus groups with adults. Students completed the self-administered Knowledge, Attitudes, and Behaviors (KAB) survey, and a Physical Activity Questionnaire (PAQ). Barriers to physical activity at schools included a lack of facilities, equipment, and trained staff persons for PE. Adults were not consistently active with their children, but they were highly supportive of their children's activity level. Children reported a strong enjoyment of physical activity and strong peer support to be physically active. Weather conditions, safety concerns, and homework/chores were common barriers to physical activity reported by children and adult caregivers. The information was used to design culturally and age-appropriate, practical interventions including the five physical activity programs for schoolchildren in the Pathways study. PMID:11759094

  2. Major Dietary Patterns in Relation to General and Central Obesity among Chinese Adults

    PubMed Central

    Yu, Canqing; Shi, Zumin; Lv, Jun; Du, Huaidong; Qi, Lu; Guo, Yu; Bian, Zheng; Chang, Liang; Tang, Xuefeng; Jiang, Qilian; Mu, Huaiyi; Pan, Dongxia; Chen, Junshi; Chen, Zhengming; Li, Liming

    2015-01-01

    Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30–79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI) and waist circumference (WC); the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR): 1.06, 95% confidence interval (CI): 1.03–1.08) and central obesity (PR: 1.07, 95% CI: 1.06–1.08). The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02–1.09) and 1.17 (1.25–1.18), respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships. PMID:26184308

  3. Major Dietary Patterns in Relation to General and Central Obesity among Chinese Adults.

    PubMed

    Yu, Canqing; Shi, Zumin; Lv, Jun; Du, Huaidong; Qi, Lu; Guo, Yu; Bian, Zheng; Chang, Liang; Tang, Xuefeng; Jiang, Qilian; Mu, Huaiyi; Pan, Dongxia; Chen, Junshi; Chen, Zhengming; Li, Liming

    2015-07-01

    Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30-79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI) and waist circumference (WC); the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR): 1.06, 95% confidence interval (CI): 1.03-1.08) and central obesity (PR: 1.07, 95% CI: 1.06-1.08). The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02-1.09) and 1.17 (1.25-1.18), respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships. PMID:26184308

  4. Psychometric Properties of Work-Related Behavior and Experience Patterns (AVEM) Scale

    ERIC Educational Resources Information Center

    Gencer, R. Timucin; Boyacioglu, Hayal; Kiremitci, Olcay; Dogan, Birol

    2010-01-01

    "Work-Related Behaviour and Experience Patterns" (AVEM) has been developed with the intention of determining the occupation related behaviour and lifestyle models of professionals. This study has been conducted to test the validity and reliability of MEDYAM, the abbreviated Turkish equivalent of AVEM. 373 teachers from 10 different primary and…

  5. Attributes and National Behavior, Part 2: Modern International Relations Monograph Series. Patterns of Cooperation: Distance Theory.

    ERIC Educational Resources Information Center

    Vincent, Jack E.

    Part of a large scale research project to test various theories with regard to their ability to analyze international relations, this monograph presents data on the application of distance theory to patterns of cooperation among nations. Distance theory implies that international relations systems (nations, organizations, individuals, etc.) can be…

  6. The relationship of major American dietary patterns to age-related macular degeneration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We hypothesized that major American dietary patterns are associated with age-related macular degeneration (AMD) risk. This was a cross-sectional study with 8,103 eyes from 4,088 eligible participants in the baseline Age-Related Eye Disease Study (AREDS) were classified into control (n=2,739), early ...

  7. Relation between heart beat fluctuations and cyclic alternating pattern during sleep in insomnia patients.

    PubMed

    de Leon-Lomeli, R; Murguia, J S; Chouvarda, I; Mendez, M O; Gonzalez-Galvan, E; Alba, A; Milioli, G; Grassi, A; Terzano, M G; Parrino, L

    2014-01-01

    Insomnia is a condition that affects the nervous and muscular system. Thirty percent of the population between 18 and 60 years suffers from insomnia. The effects of this disorder involve problems such as poor school or job performance and traffic accidents. In addition, patients with insomnia present changes in the cardiac function during sleep. Furthermore, the structure of electroencephalographic A-phases, which builds up the Cyclic Alternating Pattern during sleep, is related to the insomnia events. Therefore, the relationship between these brain activations (A-phases) and the autonomic nervous system would be of interest, revealing the interplay of central and autonomic activity during insomnia. With this goal, a study of the relationship between A-phases and heart rate fluctuations is presented. Polysomnography recording of five healthy subjects, five sleep misperception patients and five patients with psychophysiological insomnia were used in the study. Detrended Fluctuation Analysis (DFA) was used in order to evaluate the heart rate dynamics and this was correlated with the number of A-phases. The results suggest that pathological patients present changes in the dynamics of the heart rate. This is reflected in the modification of A-phases dynamics, which seems to modify of heart rate dynamics. PMID:25570435

  8. "Imposed" and "inherent" mucosal activity patterns. Their composite representation of olfactory stimuli

    PubMed Central

    1987-01-01

    Both regional differences in mucosal sensitivity and a gas chromatography-like process along the mucosal sheet have been separately proposed in two sets of earlier studies to produce different odorant-dependent activity patterns across the olfactory mucosa. This investigation evaluated, in one study, whether and to what degree these two mechanisms contribute to the generation of these activity patterns. Summated multiunit discharges were simultaneously recorded from lateral (LN) and medial (MN) sites on the bullfrog's olfactory nerve to sample the mucosal activity occurring near the internal and external nares, respectively. Precisely controlled sniffs of four odorants (benzaldehyde, butanol, geraniol, and octane) were drawn through the frog's olfactory sac in both the forward (H1) and reverse (H2) hale directions. By combining the four resulting measurements, LNH1, LNH2, MNH1, and MNH2, in different mathematical expressions, indexes reflecting the relative effects of the chromatographic process, regional sensitivity, and hale direction could be calculated. Most importantly, the chromatographic process and the regional sensitivity differences both contributed significantly to the mucosal activity patterns. However, their relative roles varied markedly among the four odorants, ranging from complete dominance by either one to substantial contributions from each. In general, the more strongly an odorant was sorbed by the mucosa, the greater was the relative effect of the chromatographic process; the weaker the sorption, the greater the relative effect of regional sensitivity. Similarly, the greater an odorant's sorption, the greater was the effect of hale direction. Other stimulus variables (sniff volume, sniff duration, and the number of molecules within the sniff) had marked effects upon the overall size of the response. For strongly sorbed odorants, the effect of increasing volume was positive; for a weakly sorbed odorant, it was negative. The reverse may be true

  9. Observation of harmonically related solar radio zebra patterns in the 1-4 GHz frequency range

    NASA Astrophysics Data System (ADS)

    Sawant, H. S.; Karlický, M.; Fernandes, F. C. R.; Cecatto, J. R.

    2002-12-01

    A unique case of two zebra patterns related harmonically with ratio of ~ 1:2 was observed by distant radio telescopes at São José dos Campos and Ondřejov Observatories. Accompanied zebras show that the ratio of frequencies of the neighboring zebra lines is in the range of 1.009-1.037. There is a tendency of a decrease of this ratio with decreasing frequency within the specific zebra pattern. Both facts speak in favour of plasma emission models for the zebra pattern fine structure in radio burst continua.

  10. Relative validity of dietary patterns during pregnancy assessed with a food frequency questionnaire.

    PubMed

    Loy, See-Ling; Jan Mohamed, Hamid Jan B

    2013-09-01

    This study aimed to assess the relative validity of maternal dietary patterns derived from a semi-quantitative food frequency questionnaire (FFQ). A total of 162 pregnant women aged 19-40-years-old were enrolled from the Universiti Sains Malaysia (USM) Birth Cohort Study in year 2010 and 2011. The FFQ was compared with three 24-h dietary recalls (DRs). Two major dietary patterns were derived from the principle component analysis which are labeled as Healthy and Less-Healthy patterns. The Pearson correlation coefficients between FFQ and DRs for Healthy and Less-Healthy patterns were 0.59 and 0.63, respectively. At least 45% of the participants were correctly classified into the same third from the FFQ and DR for both dietary patterns. The weighted kappa showed moderate agreement for Healthy pattern while good agreement for Less-Healthy pattern between these two dietary assessment methods. Our results indicate reasonable validity of the dietary patterns identified from the FFQ in pregnant women. PMID:23594439

  11. 19th century auroral observations reveal solar activity patterns

    NASA Astrophysics Data System (ADS)

    Silverman, Sam

    Growing interest in the aurora in the early part of the eighteenth century, which resulted from the spectacular reappearance of the aurora in 1707 and 1716, followed a relative scarcity of great auroras during the Maunder minimum, a period of prolonged reduced solar activity from about 1645-1715. Observations in the early eighteenth century led to questions about the geographical extent, nature, and temporal variability of the auroras. Typically, such observations were included as part of recorded meteorological notations, though occasionally early astronomers, such as Tycho Brahe in the 1590s, included auroras in their observations. Meteorological observations were important because of the effects of weather and climate on agriculture, and, according to the belief at the time, on disease.

  12. Disruption of dopamine neuron activity pattern regulation through selective expression of a human KCNN3 mutation.

    PubMed

    Soden, Marta E; Jones, Graham L; Sanford, Christina A; Chung, Amanda S; Güler, Ali D; Chavkin, Charles; Luján, Rafael; Zweifel, Larry S

    2013-11-20

    The calcium-activated small conductance potassium channel SK3 plays an essential role in the regulation of dopamine neuron activity patterns. Here we demonstrate that expression of a human disease-related SK3 mutation (hSK3Δ) in dopamine neurons of mice disrupts the balance between tonic and phasic dopamine neuron activity. Expression of hSK3Δ suppressed endogenous SK currents, reducing coupling between SK channels and NMDA receptors (NMDARs) and increasing permissiveness for burst firing. Consistent with enhanced excitability of dopamine neurons, hSK3Δ increased evoked calcium signals in dopamine neurons in vivo and potentiated evoked dopamine release. Specific expression of hSK3Δ led to deficits in attention and sensory gating and heightened sensitivity to a psychomimetic drug. Sensory-motor alterations and psychomimetic sensitivity were recapitulated in a mouse model of transient, reversible dopamine neuron activation. These results demonstrate the cell-autonomous effects of a human ion channel mutation on dopamine neuron physiology and the impact of activity pattern disruption on behavior. PMID:24206670

  13. Time Use Patterns between Maintenance, Subsistence and Leisure Activities: A Case Study in China

    ERIC Educational Resources Information Center

    Hui-fen, Zhou; Zhen-shan, Li; Dong-qian, Xue; Yang, Lei

    2012-01-01

    The Chinese government conducted its first time use survey of the activities of Chinese individuals in 2008. Activities were classified into three broad types, maintenance activities, subsistence activities and leisure activities. Time use patterns were defined by an individuals' time spent on maintenance, subsistence and leisure activities each…

  14. Contrasting activity patterns of sympatric and allopatric black and grizzly bears

    USGS Publications Warehouse

    Schwartz, C.C.; Cain, S.L.; Podruzny, S.; Cherry, S.; Frattaroli, L.

    2010-01-01

    The distribution of grizzly (Ursus arctos) and American black bears (U. americanus) overlaps in western North America. Few studies have detailed activity patterns where the species are sympatric and no studies contrasted patterns where populations are both sympatric and allopatric. We contrasted activity patterns for sympatric black and grizzly bears and for black bears allopatric to grizzly bears, how human influences altered patterns, and rates of grizzlyblack bear predation. Activity patterns differed between black bear populations, with those sympatric to grizzly bears more day-active. Activity patterns of black bears allopatric with grizzly bears were similar to those of female grizzly bears; both were crepuscular and day-active. Male grizzly bears were crepuscular and night-active. Both species were more night-active and less day-active when ???1 km from roads or developments. In our sympatric study area, 2 of 4 black bear mortalities were due to grizzly bear predation. Our results suggested patterns of activity that allowed for intra- and inter-species avoidance. National park management often results in convergence of locally high human densities in quality bear habitat. Our data provide additional understanding into how bears alter their activity patterns in response to other bears and humans and should help park managers minimize undesirable bearhuman encounters when considering needs for temporal and spatial management of humans and human developments in bear habitats. ?? 2010 The Wildlife Society.

  15. Computer keyswitch force-displacement characteristics affect muscle activity patterns during index finger tapping.

    PubMed

    Lee, David L; Kuo, Po-Ling; Jindrich, Devin L; Dennerlein, Jack T

    2009-10-01

    This study examined the effect of computer keyboard keyswitch design on muscle activity patterns during finger tapping. In a repeated-measures laboratory experiment, six participants tapped with their index fingers on five isolated keyswitch designs with varying force-displacement characteristics that provided pairwise comparisons for the design factors of (1) activation force (0.31 N vs. 0.59 N; 0.55 N vs. 0.93 N), (2) key travel (2.5mm vs. 3.5mm), and (3) shape of the force-displacement curve as realized through buckling-spring vs. rubber-dome switch designs. A load cell underneath the keyswitch measured vertical fingertip forces, and intramuscular fine wire EMG electrodes measured muscle activity patterns of two intrinsic (first lumbricalis, first dorsal interossei) and three extrinsic (flexor digitorum superficialis, flexor digitorum profundus, and extensor digitorum communis) index finger muscles. The amplitude of muscle activity for the first dorsal interossei increased 25.9% with larger activation forces, but not for the extrinsic muscles. The amplitude of muscle activity for the first lumbricalis and the duration of muscle activities for the first dorsal interossei and both extrinsic flexor muscles decreased up to 40.4% with longer key travel. The amplitude of muscle activity in the first dorsal interossei increased 36.6% and the duration of muscle activity for all muscles, except flexor digitorum profundus, decreased up to 49.1% with the buckling-spring design relative to the rubber-dome design. These findings suggest that simply changing the force-displacement characteristics of a keyswitch changes the dynamic loading of the muscles, especially in the intrinsic muscles, during keyboard work. PMID:18515146

  16. Pattern of physical activity among persons with type 2 diabetes with special consideration to daily routine

    PubMed Central

    Arshad, Rozina; Younis, Bilal Bin; Masood, Junaid; Tahira, Maham; Khurhsid, Saima

    2016-01-01

    Objective: Physical activity is essential in maintaining a healthy lifestyle. Physical activity can improve general health, quality of life and diabetes management. The aim and objective of the study was to assess the physical activity trends in daily routine of people with type 2 diabetes. Methods: Two hundred persons with diabetes from four different clinical settings were included to access the trends of physical activity using a customized questionnaire EPIC-2. Pattern of physical activity was assessed across a set of domains including sleep time, hours of TV watch, preferred mode of transport for specific distance and household activities. Data was analyzed using SPSS 21. Results: Out of 200 persons with diabetes, 104(52%) were male and 96 (48%) were female. Out of the total sample of patients, 85 (81.7%) Male and 80 (83.3%) female patients preferred walk to cover a distance of less than one mile. There was a significant difference in selection of mode of transport for all other specified distance, esp. in female patients with both age groups. There was insignificant difference for physical activity pattern related to household activities in young and elderly male subjects. The mean sleeping time for younger male subjects on weekend was 464.31± 88.88 minutes/day and for elder it was 418.65± 102.66 minutes/day while for young female subjects was 476.25± 113.74 minutes/day and in female elderly subjects it was 420.62± 120.62 minutes/day respectively. Conclusion: In type 2 diabetics we observed a low level of physical activity which may be detrimental for the control of diabetes mellitus. PMID:27022382

  17. Chronic neck pain alters muscle activation patterns to sudden movements.

    PubMed

    Boudreau, Shellie A; Falla, Deborah

    2014-06-01

    The aim of this study was to assess the activation of the sternocleidomastoid (SCM) and splenius capitis (SC) muscles in response to unanticipated, full body perturbations in individuals with chronic neck pain (NP) and age-matched healthy controls (HC). Individuals with NP had a history of NP for 8.9 ± 7.8 years, rated the intensity of NP as 4.2 ± 2.0 (score out of 10), and scored 15.3 ± 6.5 on the Neck Disability Index. Participants stood on a moveable platform during which 32 randomized postural perturbations (eight repetitions of four perturbation types: 8 cm forward slide (FS), 8 cm backward slides, 10° forward tilt, and 10° backward tilt) with varying inter-perturbation time intervals were performed over a period of 5 min. Bilateral surface electromyography (EMG) from the SCM and SC was recorded, and the onset time and the average rectified value of the EMG signal was determined for epochs of 100 ms; starting 100 ms prior to and 500 ms after the perturbation onset. Individuals with NP, as compared to HC, demonstrated delayed onset times and reduced EMG amplitude of the SCM and SC muscles in response to all postural perturbations. Such findings were most pronounced following the FS postural perturbation (healthy vs. NP for SCM 83.3 ± 8.0 vs. 86.3 ± 4.4 and SC 75.6 ± 3.5 vs. 89.3 ± 4.2), which was also associated with the greatest change (expressed in % relative to baseline) in EMG amplitude (healthy vs. NP for SCM 206.6 ± 50.4 vs. 115.9 ± 15.7 and SC 83.4 ± 19.2 vs. 69.2 ± 10.9) across all postural perturbations types. Individuals with NP display altered neural control of the neck musculature in response to rapid, unanticipated full body postural perturbations. Although the relative timing of neck musculature activity in individuals with NP appears to be intact, simultaneous co-activation of the neck musculature emerges for unanticipated anterior-posterior postural perturbations. PMID:24632836

  18. Age-related shifts in brain activity dynamics during task switching.

    PubMed

    Jimura, Koji; Braver, Todd S

    2010-06-01

    Cognitive aging studies have suggested that older adults show declines in both sustained and transient cognitive control processes. However, previous neuroimaging studies have primarily focused on age-related change in the magnitude, but not temporal dynamics, of brain activity. The present study compared brain activity dynamics in healthy old and young adults during task switching. A mixed blocked/event-related functional magnetic resonance imaging design enabled separation of transient and sustained neural activity associated with cognitive control. Relative to young adults, older adults exhibited not only decreased sustained activity in the anterior prefrontal cortex (aPFC) during task-switching blocks but also increased transient activity on task-switch trials. Another pattern of age-related shift in dynamics was present in the lateral PFC (lPFC) and posterior parietal cortex (PPC), with younger adults showing a cue-related response during task-switch trials in lPFC and PPC, whereas older adults exhibited switch-related activation during the cue period in PPC only. In all 3 regions, these qualitatively distinct patterns of brain activity predicted qualitatively distinct patterns of behavioral performance across the 2 age groups. Together, these results suggest that older adults may shift from a proactive to reactive cognitive control strategy as a means of retaining relatively preserved behavioral performance in the face of age-related neurocognitive changes. PMID:19805420

  19. Age-Related Shifts in Brain Activity Dynamics during Task Switching

    PubMed Central

    Braver, Todd S.

    2010-01-01

    Cognitive aging studies have suggested that older adults show declines in both sustained and transient cognitive control processes. However, previous neuroimaging studies have primarily focused on age-related change in the magnitude, but not temporal dynamics, of brain activity. The present study compared brain activity dynamics in healthy old and young adults during task switching. A mixed blocked/event-related functional magnetic resonance imaging design enabled separation of transient and sustained neural activity associated with cognitive control. Relative to young adults, older adults exhibited not only decreased sustained activity in the anterior prefrontal cortex (aPFC) during task-switching blocks but also increased transient activity on task-switch trials. Another pattern of age-related shift in dynamics was present in the lateral PFC (lPFC) and posterior parietal cortex (PPC), with younger adults showing a cue-related response during task-switch trials in lPFC and PPC, whereas older adults exhibited switch-related activation during the cue period in PPC only. In all 3 regions, these qualitatively distinct patterns of brain activity predicted qualitatively distinct patterns of behavioral performance across the 2 age groups. Together, these results suggest that older adults may shift from a proactive to reactive cognitive control strategy as a means of retaining relatively preserved behavioral performance in the face of age-related neurocognitive changes. PMID:19805420

  20. Relating practitioner needs to research activities

    NASA Technical Reports Server (NTRS)

    Feather, M. S.; Menzies, T.; Connelly, J. R.

    2003-01-01

    We present an approach to matching needs (practioner requirements) to solutions (researcher activities). A taxonomical classification scheme acts as intermediary between needs and activities. Expert practitioners exprss their needs in terms of this taxonomy. Researchers express their activities in the same terms. A decision support tool is used to assist in the combination and study of their expressions of needs and activities.

  1. Cultural ecology of dietary change accompanying changing activity patterns among the Shipibo

    SciTech Connect

    Behrens, C.A.

    1986-12-01

    Shipibo Indians, who formed a village to establish a school and health clinic, are gradually depleting local fish and game resources. Men, recently adopting rice as a cash crop, tend to fish and hunt less than other men working only their subsistence gardens. Sale of fish and game in the village is becoming common, and pigs, once raised exclusively for sale to non-Shipibo, are now more regularly eaten and used for attracting agricultural labor. Other research has indicated that cash cropping often competes for workers' time in subsistence and so dietary change usually accompanies changing activity patterns. This paper explores the latter possibility by examining the relationship between cash cropping, wild meat procurement, and diet among the Shipibo. Time allocation and food consumption data are analyzed statistically to test a mathematical theory and model which relates indigenous work patterns to diet.

  2. Healthy and Unhealthy Dietary Patterns Are Related to Depression: A Case-Control Study

    PubMed Central

    Khosravi, Maryam; Majdzadeh, Reza; Nejati, Somayeh; Darabi, Samaneh; Raisi, Firoozeh; Esmaillzadeh, Ahmad; Sorayani, Maryam

    2015-01-01

    Objective Major depressive disorder is the leading cause of disability around the world. The relationship between depression and dietary patterns has been reported in a few studies but with controversial results. This study aimed to investigate this relationship in an Iranian population. Methods In our study, 330 depressed patients (cases) and healthy people (controls) (1:2) were individually matched according to age, sex and area of residence. New cases of depression were recruited from two psychiatric clinics in Tehran. Interviewers went to each patient's residential area, and invited qualified individuals to participate in the study as controls. Food intake over the past year was collected using a validated semi quantitative food frequency questionnaire. Dietary patterns were determined by the principal components method. Binary logistic regression was used to test the effect of dietary patterns on depression. Results We identified two major dietary patterns by using factor analysis: the healthy and unhealthy dietary patterns. We categorized the scores of these patterns to quartiles. After adjusting for non-depression drug use, job, marital status, children number, and body mass index, the relations of depression and quartiles of two dietary patterns are significant (p=0.04 & p=0.01, respectively). Compared with participants in the lowest quartile, those in the highest quartile had significantly lower odds ratio (OR) for depression in healthy dietary pattern, and higher OR for depression in unhealthy dietary pattern. Conclusion This study indicates that healthy and unhealthy dietary patterns may be associated with the risk of depression. The results can be used for developing interventions that aim to promote healthy eating for the prevention of depression. PMID:26508953

  3. Western dietary pattern is related to premenstrual syndrome: a case-control study.

    PubMed

    Farasati, Negin; Siassi, Fereydoun; Koohdani, Fariba; Qorbani, Mostafa; Abashzadeh, Karolin; Sotoudeh, Gity

    2015-12-28

    Although premenstrual syndrome (PMS) affects a large number of women of reproductive age, the aetiology of this disorder has not yet been fully elucidated. The relationship between food intake and PMS morbidity has been investigated in several studies, but dietary patterns of PMS patients have not been taken into consideration up to now. We examined dietary patterns of 320 nurses with (n 160) and without (n 160) PMS in a case-control study. Food intakes over the past year were determined using semi-quantitative FFQ. Factor analysis was used to identify the main dietary patterns, and logistic regression was used to model the relationship between dietary patterns and PMS morbidity. Three dietary patterns were identified in the analysis: healthy, Western and traditional. After adjustment for age, BMI, menstrual cycles, physical activity and energy intake, participants in the second (OR 2·53; 95 % CI 1·18, 5·43) and third (OR 4·39; 95 % CI 1·97, 9·81) quintiles of the Western dietary pattern were more likely to experience PMS compared with those in the first quintile. The study findings therefore reveal that Western dietary pattern might be associated with PMS morbidity. However, this result should be interpreted with caution as there was no evidence of a dose-response relationship. Future studies are needed to confirm our findings in other populations. PMID:26459000

  4. The nocturnal bottleneck and the evolution of activity patterns in mammals.

    PubMed

    Gerkema, Menno P; Davies, Wayne I L; Foster, Russell G; Menaker, Michael; Hut, Roelof A

    2013-08-22

    In 1942, Walls described the concept of a 'nocturnal bottleneck' in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail. PMID:23825205

  5. Sex Differences in Brain Activity Related to General and Emotional Intelligence

    ERIC Educational Resources Information Center

    Jausovec, Norbert; Jausovec, Ksenija

    2005-01-01

    The study investigated gender differences in resting EEG (in three individually determined narrow [alpha] frequency bands) related to the level of general and emotional intelligence. Brain activity of males decreased with the level of general intelligence, whereas an opposite pattern of brain activity was observed in females. This difference was…

  6. Database and Related Activities in Japan

    NASA Astrophysics Data System (ADS)

    Murakami, Izumi; Kato, Daiji; Kato, Masatoshi; Sakaue, Hiroyuki A.; Kato, Takako; Ding, Xiaobin; Morita, Shigeru; Kitajima, Masashi; Koike, Fumihiro; Nakamura, Nobuyuki; Sakamoto, Naoki; Sasaki, Akira; Skobelev, Igor; Tsuchida, Hidetsugu; Ulantsev, Artemiy; Watanabe, Tetsuya; Yamamoto, Norimasa

    2011-05-01

    We have constructed and made available atomic and molecular (AM) numerical databases on collision processes such as electron-impact excitation and ionization, recombination and charge transfer of atoms and molecules relevant for plasma physics, fusion research, astrophysics, applied-science plasma, and other related areas. The retrievable data is freely accessible via the internet. We also work on atomic data evaluation and constructing collisional-radiative models for spectroscopic plasma diagnostics. Recently we have worked on Fe ions and W ions theoretically and experimentally. The atomic data and collisional-radiative models for these ions are examined and applied to laboratory plasmas. A visible M1 transition of W26+ ion is identified at 389.41 nm by EBIT experiments and theoretical calculations. We have small non-retrievable databases in addition to our main database. Recently we evaluated photo-absorption cross sections for 9 atoms and 23 molecules and we present them as a new database. We established a new association "Forum of Atomic and Molecular Data and Their Applications" to exchange information among AM data producers, data providers and data users in Japan and we hope this will help to encourage AM data activities in Japan.

  7. WHOLE GRAINS AND RELATED DIETARY PATTERNS IN RELATION TO WEIGHT GAIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obesity rates continue to rise in the US and currently an estimated two thirds of Americans are overweight and about 31% are obese. Although genetics play a role, environmental factors such as diet and physical activity are indisputably the major factors contributing to the obesity epidemic. Weig...

  8. Influence of human activity patterns on epidemiology of plague in Western Usambara Mountains, Tanzania.

    PubMed

    Hubeau, Marianne; Gulinck, Hubert; Kimaro, Didas N; Hieronimo, Proches; Meliyo, Joel

    2014-07-01

    Human plague has been a recurring public health threat in some villages in the Western Usambara Mountains, Tanzania, in the period between 1980 and 2004. Despite intensive past biological and medical research, the reasons for the plague outbreaks in the same set of villages remain unknown. Plague research needs to broaden its scope and formulate new hypotheses. This study was carried out to establish relationships between the nature and the spatial extent of selected human activities on one hand, and the reported plague cases on the other hand. Three outdoor activities namely, fetching water, collecting firewood and going to the market, were selected. Through enquiries the activity patterns related to these activities were mapped in 14 villages. Standard deviation ellipses represent the extent of action spaces. Over 130 activity types were identified and listed. Of these, fetching water, collecting firewood and going to the market were used for further analysis. The results indicate a significant correlation between the plague frequency and the size of these action spaces. Different characteristics of land use and related human activities were correlated with the plague frequency at village and hamlet levels. Significant relationships were found between plague frequency and specific sources of firewood and water, and specific market places. PMID:26867274

  9. Clustering and Pattern Formation in Chemorepulsive Active Colloids.

    PubMed

    Liebchen, Benno; Marenduzzo, Davide; Pagonabarraga, Ignacio; Cates, Michael E

    2015-12-18

    We demonstrate that migration away from self-produced chemicals (chemorepulsion) generates a generic route to clustering and pattern formation among self-propelled colloids. The clustering instability can be caused either by anisotropic chemical production, or by a delayed orientational response to changes of the chemical environment. In each case, chemorepulsion creates clusters of a self-limiting area which grows linearly with self-propulsion speed. This agrees with recent observations of dynamic clusters in Janus colloids (albeit not yet known to be chemorepulsive). More generally, our results could inform design principles for the self-assembly of chemorepulsive synthetic swimmers and/or bacteria into nonequilibrium patterns. PMID:26722949

  10. Clustering and Pattern Formation in Chemorepulsive Active Colloids

    NASA Astrophysics Data System (ADS)

    Liebchen, Benno; Marenduzzo, Davide; Pagonabarraga, Ignacio; Cates, Michael E.

    2015-12-01

    We demonstrate that migration away from self-produced chemicals (chemorepulsion) generates a generic route to clustering and pattern formation among self-propelled colloids. The clustering instability can be caused either by anisotropic chemical production, or by a delayed orientational response to changes of the chemical environment. In each case, chemorepulsion creates clusters of a self-limiting area which grows linearly with self-propulsion speed. This agrees with recent observations of dynamic clusters in Janus colloids (albeit not yet known to be chemorepulsive). More generally, our results could inform design principles for the self-assembly of chemorepulsive synthetic swimmers and/or bacteria into nonequilibrium patterns.

  11. 29 CFR 779.207 - Related activities in retail operations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Related activities in retail operations. 779.207 Section... Coverage Related Activities § 779.207 Related activities in retail operations. In the case of an enterprise which has one or more retail or service establishments, all of the activities which are performed...

  12. 29 CFR 779.207 - Related activities in retail operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Related activities in retail operations. 779.207 Section... Coverage Related Activities § 779.207 Related activities in retail operations. In the case of an enterprise which has one or more retail or service establishments, all of the activities which are performed...

  13. Tsunami related to solar and geomagnetic activity

    NASA Astrophysics Data System (ADS)

    Cataldi, Gabriele; Cataldi, Daniele; Straser, Valentino

    2016-04-01

    The authors of this study wanted to verify the existence of a correlation between earthquakes of high intensity capable of generating tsunami and variations of solar and Earth's geomagnetic activity. To confirming or not the presence of this kind of correlation, the authors analyzed the conditions of Spaceweather "near Earth" and the characteristics of the Earth's geomagnetic field in the hours that preceded the four earthquakes of high intensity that have generated tsunamis: 1) Japan M9 earthquake occurred on March 11, 2011 at 05:46 UTC; 2) Japan M7.1 earthquake occurred on October 25, 2013 at 17:10 UTC; 3) Chile M8.2 earthquake occurred on April 1, 2014 at 23:46 UTC; 4) Chile M8.3 earthquake occurred on September 16, 2015 at 22:54 UTC. The data relating to the four earthquakes were provided by the United States Geological Survey (USGS). The data on ion density used to realize the correlation study are represented by: solar wind ion density variation detected by ACE (Advanced Composition Explorer) Satellite, in orbit near the L1 Lagrange point, at 1.5 million of km from Earth, in direction of the Sun. The instrument used to perform the measurement of the solar wind ion density is the Electron, Proton, and Alpha Monitor (EPAM) instrument, equipped on the ACE Satellite. To conduct the study, the authors have taken in consideration the variation of the solar wind protons density of three different energy fractions: differential proton flux 1060-1900 keV (p/cm^2-sec-ster-MeV); differential proton flux 761-1220 keV (p/cm^2-sec-ster-MeV); differential proton flux 310-580 keV (p/cm^2-sec-ster-MeV). Geomagnetic activity data were provided by Tromsø Geomagnetic Observatory (TGO), Norway; by Scoresbysund Geomagnetic Observatory (SCO), Greenland, Denmark and by Space Weather Prediction Center of Pushkov Institute of terrestrial magnetism, ionosphere and radio wave propagation (IZMIRAN), Troitsk, Moscow Region. The results of the study, in agreement with what already

  14. The Relationship of Major American Dietary Patterns to Age-related Macular Degeneration

    PubMed Central

    Chiu, Chung-Jung; Chang, Min-Lee; Zhang, Fang Fang; Li, Tricia; Gensler, Gary; Schleicher, Molly; Taylor, Allen

    2014-01-01

    PURPOSE We hypothesized that major American dietary patterns are associated with age-related macular degeneration (AMD) risk. DESIGN Cross-sectional study METHODS 8,103 eyes from 4,088 eligible participants in the baseline Age-Related Eye Disease Study (AREDS) were classified into control (n=2,739), early AMD (n=4,599), and advanced AMD (n=765) by AREDS AMD Classification System. Food consumption data were collected by a 90-item food frequency questionnaire. RESULTS Two major dietary patterns were identified by factor (principle component) analysis based on 37 food groups and named Oriental and Western patterns. The Oriental pattern was characterized by higher intake of vegetables, legumes, fruit, whole grains, tomatoes, and seafood. The Western pattern was characterized by higher intake of red meat, processed meat, high-fat dairy products, French fries, refined grains, and eggs. We ranked our participants according to how closely their diets line up with the two patterns by calculating the two factor scores for each participant. For early AMD, multivariate-adjusted odds ratio (OR) from generalized estimating equation logistic analysis comparing the highest to lowest quintile of the Oriental pattern score was ORE5O=0.74 (95% confidence interval (CI): 0.59–0.91; Ptrend=0.01), and the OR comparing the highest to lowest quintile of the Western pattern score was ORE5W=1.56 (1.18–2.06; Ptrend=0.01). For advanced AMD, the ORA5O was 0.38 (0.27–0.54; Ptrend<0.0001), and the ORA5W was 3.70 (2.31–5.92; Ptrend<0.0001). CONCLUSIONS Our data indicate that overall diet is significantly associated with the odds of AMD and that dietary management as an AMD prevention strategy warrants further study. PMID:24792100

  15. Responses of neurones in the cat's visual cerebral cortex to relative movement of patterns

    PubMed Central

    Burns, B. Delisle; Gassanov, U.; Webb, A. C.

    1972-01-01

    1. We have investigated the responses of single neurones in the visual cerebral cortex of the unanaesthetized, isolated cat's forebrain to excitation of one retina with patterned light. The responses of twenty-six cells to the relative movement of two patterns in the visual field have been recorded. 2. We used several forms of relative movement for stimulation, but all of them involved a change in the separation of two parallel and straight light-dark edges. 3. Responses to this form of stimulation were compared with the responses of the same cells to simple movement, that is, movement of the same patterns without change of distance between their borders. 4. All cells showed a response to relative movement that differed from their response to simple movement. 5. The time-locked phasic response differed in 54% of the cells tested. Of cells responding in this way, 83% of tests produced an increased phasic response. 6. Relative movement brought about changes in the mean frequency of discharge in 96% of the cells tested. 82% of these cells responded with an increased rate of firing. 7. Movement relative to a coarse background pattern affected more neurones and produced a greater change in their behaviour than did movement relative to a fine-grained pattern. 8. The neurones tested represented the central part of the visual field (0-10°); while all were affected by relative movement, those representing points furthest from the optic axis appeared to be most susceptible (we found no correlation between size of receptive field and distance from the optic axis). PMID:5083167

  16. The Pattern of Electronic Game Use and Related Bodily Discomfort in Hong Kong Primary School Children

    ERIC Educational Resources Information Center

    Lui, Donald P. Y.; Szeto, Grace P. Y.; Jones, Alice Y. M.

    2011-01-01

    The present study examined the usage pattern of electronic game devices among primary school children in Hong Kong. Commonly used types of games devices were grouped into three main categories: large-screen/TV-based games, small handheld game devices and active game devices. A survey was conducted among 476 students in a local primary school, with…

  17. Activity patterns in a panel of outdoor workers exposed to oxidant pollution

    SciTech Connect

    Shamoo, D.A.; Johnson, T.R.; Trim, S.C.; Little, D.E.; Linn, W.S.; Hackney, J.D. )

    1991-10-01

    We investigated summer activity patterns in a panel of volunteers drawn from a population segment with potentially high exposure to ambient oxidant pollution. The subjects were 15 men and 5 women aged 19-50, all of whom worked outdoors in the Los Angeles area at least 10 hr per week. The general approach was to (i) calibrate the relationship between ventilation rate (VR) and heart rate (HR) for each subject in controlled exercise; (ii) have subjects monitor their own normal activities with diaries and electronic HR recorders; (iii) estimate VR from HR recordings; and (iv) relate VR with diary descriptions of activities. Calibration data were fit to the equation log (VR) = (intercept) + (slope x HR), intercept and slope being determined separately for each individual to provide a specific equation to predict her/his VR from measured HR. Individuals' correlation coefficients relating log (VR) with HR ranged from 0.83 to 0.95. Subjects monitored themselves for three 24-hr periods during one week, including their most active work day and their most active non-work day. They wore Heart Watch(R) athletic training instruments which recorded HR once per minute; and recorded each change in their activity, location, or breathing rate in diaries. Breathing rates were classified as sleep, slow, medium, or fast. Diaries showed that sleep occupied about 33% of subject's time, slow activity 59%, medium 7%, and fast 1%. Fast activity was reported only at leisure, never at work. For the group, arithmetic means and standard deviations of predicted VR were 7 +/- 3 L/min for sleep, 12 +/- 7 for slow activity, 14 +/- 8 for medium, and 44 +/- 36 for fast. For the group and for most individuals, distributions of predicted VR within a given activity level (breathing rate) were approximately lognormal, with many values in a narrow range below the arithmetic mean and fewer values in a broader range above it.

  18. Academic Life: Monitoring Work Patterns and Daily Activities

    ERIC Educational Resources Information Center

    Forgasz, Helen J.; Leder, Gilah C.

    2006-01-01

    Academics are reported to be working longer hours and have less time for research because of increasing administrative and teaching demands. The traditional pattern of the academic enterprise appears to have changed. To explore whether this is indeed the case, the Experience Sampling Method [ESM], a research technique devised by Mihaly…

  19. Active sensing via movement shapes spatiotemporal patterns of sensory feedback.

    PubMed

    Stamper, Sarah A; Roth, Eatai; Cowan, Noah J; Fortune, Eric S

    2012-05-01

    Previous work has shown that animals alter their locomotor behavior to increase sensing volumes. However, an animal's own movement also determines the spatial and temporal dynamics of sensory feedback. Because each sensory modality has unique spatiotemporal properties, movement has differential and potentially independent effects on each sensory system. Here we show that weakly electric fish dramatically adjust their locomotor behavior in relation to changes of modality-specific information in a task in which increasing sensory volume is irrelevant. We varied sensory information during a refuge-tracking task by changing illumination (vision) and conductivity (electroreception). The gain between refuge movement stimuli and fish tracking responses was functionally identical across all sensory conditions. However, there was a significant increase in the tracking error in the dark (no visual cues). This was a result of spontaneous whole-body oscillations (0.1 to 1 Hz) produced by the fish. These movements were costly: in the dark, fish swam over three times further when tracking and produced more net positive mechanical work. The magnitudes of these oscillations increased as electrosensory salience was degraded via increases in conductivity. In addition, tail bending (1.5 to 2.35 Hz), which has been reported to enhance electrosensory perception, occurred only during trials in the dark. These data show that both categories of movements - whole-body oscillations and tail bends - actively shape the spatiotemporal dynamics of electrosensory feedback. PMID:22496294

  20. The Effects of Simulated Stuttering and Prolonged Speech on the Neural Activation Patterns of Stuttering and Nonstuttering Adults

    ERIC Educational Resources Information Center

    De Nil, Luc F.; Beal, Deryk S.; Lafaille, Sophie J.; Kroll, Robert M.; Crawley, Adrian P.; Gracco, Vincent L.

    2008-01-01

    Functional magnetic resonance imaging was used to investigate the neural correlates of passive listening, habitual speech and two modified speech patterns (simulated stuttering and prolonged speech) in stuttering and nonstuttering adults. Within-group comparisons revealed increased right hemisphere biased activation of speech-related regions…

  1. Pattern of cortical activation during processing of aversive stimuli in traumatized survivors of war and torture.

    PubMed

    Catani, Claudia; Adenauer, Hannah; Keil, Julian; Aichinger, Hannah; Neuner, Frank

    2009-09-01

    Posttraumatic stress disorder (PTSD) has been associated with an altered processing of threat-related stimuli. In particular, an attentional bias towards threat cues has been consistently found in behavioral studies. However, it is unclear whether increased attention towards threat cues translates into preferential processing as neurophysiological studies have yielded inconsistent findings. The aim of the present study was to investigate the neocortical activity related to the processing of aversive stimuli in patients with PTSD. 36 survivors of war and torture with PTSD, 21 Trauma Controls and 20 Unexposed Subjects participated in a visual evoked magnetic field study using flickering pictures of varying affective valence as stimulus material. Minimum norm source localization was carried out to estimate the distribution of sources of the evoked neuromagnetic activity in the brain. Statistical permutation analyses revealed reduced steady-state visual evoked field amplitudes over occipital areas in response to aversive pictures for PTSD patients and for Trauma Controls in comparison to unexposed subjects. Furthermore, PTSD patients showed a hyperactivation of the superior parietal cortex selectively in response to aversive stimuli, which was related to dissociative symptoms as well as to torture severity. The results indicate a different pattern of cortical activation driven by aversive stimuli depending on the experience of multiple traumatic events and PTSD. Whereas, a decreased visual processing of aversive stimuli seems to be associated with trauma exposure in general, the superior parietal activity might represent a specific process linked to the diagnosis of PTSD. PMID:19360450

  2. Comparison of patterns of use, beliefs, and attitudes related to waterpipe between beginning and established smokers

    PubMed Central

    Asfar, Taghrid; Ward, Kenneth D; Eissenberg, Thomas; Maziak, Wasim

    2005-01-01

    Background To compare patterns of use, beliefs, and attitudes related to waterpipe smoking between university students (beginning smokers) and café customers (established smokers) in Aleppo Syria, in order to explore the evolution of this smoking method. Methods Two cross-sectional surveys were conducted among representative samples of university students (total 587, 48.4% men, mean age 22 years), and waterpipe users among cafe' customers (total 268, 60% men, mean age 30 years) in Aleppo, Syria. We used interviewer-administered questionnaire inquiring about pattern of waterpipe smoking (initiation, frequency), situational characteristics of use (partner, place, sharing), beliefs related to waterpipe smoking (harmful/addictive properties of waterpipe), attitudes related to waterpipe smoking (confidence in quitting, will to quit, motivation for quitting, past year quit attempt), and cigarette smoking. Results Daily and regular patterns of smoking become more prevalent with increased duration of smoking, but intermittent smoking remains the predominant pattern of waterpipe use. Women seem to be drawn later to the habit, which seem to escape the usual taboo against women's cigarette smoking. Patterns and context of waterpipe use tend to change with progress of the practice affecting frequency, setting, and sharing of waterpipe. Unlike beginners, established waterpipe smokers seem more smoking-method oriented, more hooked on the habit, less willing to quit, and less likely to foresee challenges to quitting. Conclusion Use patterns and attitudes related to waterpipe smoking evolve to accommodate the change in dependence and life circumstances of the smoker. Most of use features, beliefs, attitudes, as well as time-course seem unique to this smoking method requiring novel approach to intervention. PMID:15733316

  3. Suboptimal Muscle Synergy Activation Patterns Generalize their Motor Function across Postures

    PubMed Central

    Sohn, M. Hongchul; Ting, Lena H.

    2016-01-01

    We used a musculoskeletal model to investigate the possible biomechanical and neural bases of using consistent muscle synergy patterns to produce functional motor outputs across different biomechanical conditions, which we define as generalizability. Experimental studies in cats demonstrate that the same muscle synergies are used during reactive postural responses at widely varying configurations, producing similarly-oriented endpoint force vectors with respect to the limb axis. However, whether generalizability across postures arises due to similar biomechanical properties or to neural selection of a particular muscle activation pattern has not been explicitly tested. Here, we used a detailed cat hindlimb model to explore the set of feasible muscle activation patterns that produce experimental synergy force vectors at a target posture, and tested their generalizability by applying them to different test postures. We used three methods to select candidate muscle activation patterns: (1) randomly-selected feasible muscle activation patterns, (2) optimal muscle activation patterns minimizing muscle effort at a given posture, and (3) generalizable muscle activation patterns that explicitly minimized deviations from experimentally-identified synergy force vectors across all postures. Generalizability was measured by the deviation between the simulated force direction of the candidate muscle activation pattern and the experimental synergy force vectors at the test postures. Force angle deviations were the greatest for the randomly selected feasible muscle activation patterns (e.g., >100°), intermediate for effort-wise optimal muscle activation patterns (e.g., ~20°), and smallest for generalizable muscle activation patterns (e.g., <5°). Generalizable muscle activation patterns were suboptimal in terms of effort, often exceeding 50% of the maximum possible effort (cf. ~5% in minimum-effort muscle activation patterns). The feasible muscle activation ranges of individual

  4. Searching for Contracting Patterns over Time: Do Prime Contractor and Subcontractor Relations Follow Similar Patterns for Professional Services Provision?

    ERIC Educational Resources Information Center

    Ponomariov, Branco; Kingsley, Gordon; Boardman, Craig

    2011-01-01

    This paper compares over a 12-year period (1) patterns of contracting between a state transportation agency and its prime contractors providing engineering design services with (2) patterns between these prime contractors and their subcontractors. We find evidence of different contracting patterns at each level that emerge over time and coexist in…

  5. MMPI-A Patterns Related to the Endorsement of Suicidal Ideation.

    ERIC Educational Resources Information Center

    Archer, Robert P.; Slesinger, David

    1999-01-01

    Studied the relationship between the occurrence of specific Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A) basic scale profile patterns and the frequency of endorsement of three items related to suicide ideation. Responses from 348 adolescents with psychiatric disorders show higher basic clinical scale profiles for those endorsing…

  6. Patterns of Expectations about Counseling: Relations to the Five-Factor Model of Personality.

    ERIC Educational Resources Information Center

    Schaub, Michael; Tokar, David M.

    1999-01-01

    Study seeks to identify groups of students who differed in their patterns of expectations about counseling and then to relate those groups to personality, as organized by the Five Factor Model (FFM). A brief interpretation is offered of each cluster that integrates information based on expectation scores and the significant personality functions.…

  7. Patterns of Nonverbal Behavior and Perceived Relational Messages Associated with Communication Reticence.

    ERIC Educational Resources Information Center

    Burgoon, Judee K.; Koper, Randall J.

    Two experiments examined nonverbal behavior patterns and relational communication perceptions associated with communication reticence. In the first experiment, pairs of friends and pairs of strangers engaged in nine-minute discussions. Subjects were rated by their interaction partners and by trained observers. Results showed that as their level of…

  8. Internet Abuse among Teenagers and Its Relations to Internet Usage Patterns and Demographics

    ERIC Educational Resources Information Center

    Gencer, Suzan Lema; Koc, Mustafa

    2012-01-01

    This study focused on exploring Internet abuse among teenagers and its relations to some Internet usage patterns and demographic characteristics in a digitalizing country, Turkey. It was designed as a cross-sectional research on three types of school that differ in their academic performances. The data were collected from 1380 high school students…

  9. Family Communication Patterns and Relational Maintenance Behavior: Direct and Mediated Associations with Friendship Closeness

    ERIC Educational Resources Information Center

    Ledbetter, Andrew M.

    2009-01-01

    In this study, both face-to-face and online relational maintenance behaviors were tested as mediators of family communication patterns and closeness with a same-sex friend. Participants included 417 young adults recruited from communication courses at a large university in the Midwestern United States. The obtained structural model demonstrated…

  10. A STRUCTURAL THEORY FOR THE PERCEPTION OF MORSE CODE SIGNALS AND RELATED RHYTHMIC PATTERNS.

    ERIC Educational Resources Information Center

    WISH, MYRON

    THE PRIMARY PURPOSE OF THIS DISSERTATION IS TO DEVELOP A STRUCTURAL THEORY, ALONG FACET-THEORETIC LINES, FOR THE PERCEPTION OF MORSE CODE SIGNALS AND RELATED RHYTHMIC PATTERNS. AS STEPS IN THE DEVELOPMENT OF THIS THEORY, MODELS FOR TWO SETS OF SIGNALS ARE PROPOSED AND TESTED. THE FIRST MODEL IS FOR A SET COMPRISED OF ALL SIGNALS OF THE…

  11. Novel expression patterns of carotenoid pathway-related gene in citrus leaves and maturing fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carotenoids are abundant in citrus fruits and vary among cultivars and species. In the present study, HPLC and real-time PCR were used to investigate the expression patterns of 23 carotenoid biosynthesis gene family members and their possible relation with carotenoid accumulation in flavedo, juice s...

  12. Transnational Islamic activism and radicalization : patterns, trends, and prognosticators.

    SciTech Connect

    Colbaugh, Richard; Engi, Dennis; LaViolette, Randall A.; Spomer, Judith E.

    2010-06-01

    The research described in this report developed the theoretical and conceptual framework for understanding, recognizing, and anticipating the origins, dynamic mechanisms, perceptions, and social structures of Islamic social reform movements in the Muslim homeland and in diaspora communities. This research has revealed valuable insights into the dynamic mechanisms associated with reform movements and, as such, offers the potential to provide indications and warnings of impending violence. This study produced the following significant findings: (1) A framework for understanding Islamic radicalization in the context of Social Movement Theory was developed and implemented. This framework provides a causal structure for the interrelationships among the myriad features of a social movement. (2) The degree to which movement-related activity shows early diffusion across multiple social contexts is a powerful distinguisher of successful and unsuccessful social movements. Indeed, this measurable appears to have significantly more predictive power than volume of such activity and also more power than various system intrinsics. (3) Significant social movements can occur only if both the intra-context 'infectivity' of the movement exceeds a certain threshold and the inter-context interactions associated with the movement occur with a frequency that is larger than another threshold. Note that this is reminiscent of, and significantly extends, well-known results for epidemic thresholds in disease propagation models. (4) More in-depth content analysis of blogs through the lens of Argumentation Theory has the potential to reveal new insights into radicalization in the context of Social Movement Theory. This connection has the potential to be of value from two important perspectives - first, this connection has the potential to provide more in depth insights into the forces underlying the emergence of radical behavior and second, this connection may provide insights into how to use

  13. [Analysis of gingival crevicular fluid. Relation of isoelectric focusing protein patterns to clinical evaluation].

    PubMed

    Aoki, Y; Yoshinaga, E; Tamazawa, O

    1988-12-01

    The purpose of this study was to determine the protein patterns in gingival crevicular fluid relation to the isoelectric focusing protein patterns of GCF and to clinical evaluations. GCF was collected with filter paper from 105 subjects. The probing depth, the gingival index (Löe & Silness) and the plaque index (Silness & Löe) as clinical evaluations The results follow: 1. The main isoelectric focusing protein patterns of GCF were between pH 5.5 and 7.5. In comparison, the GCF and the serum from the same patients showed patterns to similar serum albumin. 2. Between of GCF pH 5.5 and 7.5 the protein patterns that ranged over 60% was pI 5.65, 6.45, 6.55, 6.75 and 7.00. The frequencies of the ranges of protein patterns and clinical evaluation were compared by the X2 test. pI 5.65, 6.45, 6.55 and 6.75 and PD were significant different, as were pI 6.45, 6.55 and 6.75 and GI. But each pI and PIl. were not significantly different. PMID:3078008

  14. Patterns of metabolic activity in the treatment of schizophrenia

    SciTech Connect

    Brodie, J.D.; Christman, D.R.; Corona, J.F.; Fowler, J.S.; Gomez-Mont, F.; Jaeger, J.; Micheels, P.A.; Rotrosen, J.; Russell, J.A.; Volkow, N.D.; Wikler, A.

    1984-04-01

    Six patients with chronic schizophrenia were studied with positron emission tomography (PET) before and after neuroleptic treatment, using fluorine-18-labeled fluorodeoxyglucose. After treatment, the mean whole-slice glucose metabolic rate at the level of the basal ganglia showed a 25% increase. However, patterns of frontal hypometabolism observed with the schizophrenic patients were not altered by medication. Pattern analysis using the fast Fourier transform was applied to a set of 422 images from a mixed group of normal, depressed, and schizophrenic subjects. Reconstruction of the images with low-frequency coefficients was excellent, reducing considerably the number of variables needed to characterize each image. Hierarchical cluster analysis categorized the transformed images according to anatomical level and subject group (patient versus control). The results suggest the utility of this procedure for the classification and characterization of metabolic PET images from psychiatric patients. 8 references, 3 figures, 1 table.

  15. Estimation of rest-activity patterns using motion sensors.

    PubMed

    Hayes, Tamara L; Riley, Thomas; Pavel, Misha; Kaye, Jeffrey A

    2010-01-01

    Disrupted sleep patterns are a significant problem in the elderly, leading to increased cognitive dysfunction and risk of nursing home placement. A cost-effective and unobtrusive way to remotely monitor changing sleep patterns over time would enable improved management of this important health problem. We have developed an algorithm to derive sleep parameters such as bed time, rise time, sleep latency, and nap time from passive infrared sensors distributed around the home. We evaluated this algorithm using 404 days of data collected in the homes of 8 elderly community-dwelling elders. Data from this algorithm were highly correlated to ground truth measures (bed mats) and were surprisingly robust to variability in sensor layout and sleep habits. PMID:21097221

  16. Changes in pattern completion – a key mechanism to explain age-related recognition memory deficits?

    PubMed Central

    Vieweg, Paula; Stangl, Matthias; Howard, Lorelei R.; Wolbers, Thomas

    2016-01-01

    Accurate memory retrieval from partial or degraded input requires the reactivation of memory traces, a hippocampal mechanism termed pattern completion. Age-related changes in hippocampal integrity have been hypothesized to shift the balance of memory processes in favor of the retrieval of already stored information (pattern completion), to the detriment of encoding new events (pattern separation). Using a novel behavioral paradigm, we investigated the impact of cognitive aging (1) on recognition performance across different levels of stimulus completeness, and (2) on potential response biases. Participants were required to identify previously learned scenes among new ones. Additionally, all stimuli were presented in gradually masked versions to alter stimulus completeness. Both young and older adults performed increasingly poorly as the scenes became less complete, and this decline in performance was more pronounced in elderly participants indicative of a pattern completion deficit. Intriguingly, when novel scenes were shown, only the older adults showed an increased tendency to identify these as familiar scenes. In line with theoretical models, we argue that this reflects an age-related bias towards pattern completion. PMID:25597525

  17. Adults' Physical Activity Patterns across Life Domains: Cluster Analysis with Replication

    PubMed Central

    Rovniak, Liza S.; Sallis, James F.; Saelens, Brian E.; Frank, Lawrence D.; Marshall, Simon J.; Norman, Gregory J.; Conway, Terry L.; Cain, Kelli L.; Hovell, Melbourne F.

    2010-01-01

    Objective Identifying adults' physical activity patterns across multiple life domains could inform the design of interventions and policies. Design Cluster analysis was conducted with adults in two US regions (Baltimore-Washington DC, n = 702; Seattle-King County, n = 987) to identify different physical activity patterns based on adults' reported physical activity across four life domains: leisure, occupation, transport, and home. Objectively measured physical activity, and psychosocial and built (physical) environment characteristics of activity patterns were examined. Main Outcome Measures Accelerometer-measured activity, reported domain-specific activity, psychosocial characteristics, built environment, body mass index (BMI). Results Three clusters replicated (kappa = .90-.93) across both regions: Low Activity, Active Leisure, and Active Job. The Low Activity and Active Leisure adults were demographically similar, but Active Leisure adults had the highest psychosocial and built environment support for activity, highest accelerometer-measured activity, and lowest BMI. Compared to the other clusters, the Active Job cluster had lower socioeconomic status and intermediate accelerometer-measured activity. Conclusion Adults can be clustered into groups based on their patterns of accumulating physical activity across life domains. Differences in psychosocial and built environment support between the identified clusters suggest that tailored interventions for different subgroups may be beneficial. PMID:20836604

  18. Active patterning and asymmetric transport in a model actomyosin network

    SciTech Connect

    Wang, Shenshen; Wolynes, Peter G.

    2013-12-21

    Cytoskeletal networks, which are essentially motor-filament assemblies, play a major role in many developmental processes involving structural remodeling and shape changes. These are achieved by nonequilibrium self-organization processes that generate functional patterns and drive intracellular transport. We construct a minimal physical model that incorporates the coupling between nonlinear elastic responses of individual filaments and force-dependent motor action. By performing stochastic simulations we show that the interplay of motor processes, described as driving anti-correlated motion of the network vertices, and the network connectivity, which determines the percolation character of the structure, can indeed capture the dynamical and structural cooperativity which gives rise to diverse patterns observed experimentally. The buckling instability of individual filaments is found to play a key role in localizing collapse events due to local force imbalance. Motor-driven buckling-induced node aggregation provides a dynamic mechanism that stabilizes the two-dimensional patterns below the apparent static percolation limit. Coordinated motor action is also shown to suppress random thermal noise on large time scales, the two-dimensional configuration that the system starts with thus remaining planar during the structural development. By carrying out similar simulations on a three-dimensional anchored network, we find that the myosin-driven isotropic contraction of a well-connected actin network, when combined with mechanical anchoring that confers directionality to the collective motion, may represent a novel mechanism of intracellular transport, as revealed by chromosome translocation in the starfish oocyte.

  19. Active patterning and asymmetric transport in a model actomyosin network

    NASA Astrophysics Data System (ADS)

    Wang, Shenshen; Wolynes, Peter G.

    2013-12-01

    Cytoskeletal networks, which are essentially motor-filament assemblies, play a major role in many developmental processes involving structural remodeling and shape changes. These are achieved by nonequilibrium self-organization processes that generate functional patterns and drive intracellular transport. We construct a minimal physical model that incorporates the coupling between nonlinear elastic responses of individual filaments and force-dependent motor action. By performing stochastic simulations we show that the interplay of motor processes, described as driving anti-correlated motion of the network vertices, and the network connectivity, which determines the percolation character of the structure, can indeed capture the dynamical and structural cooperativity which gives rise to diverse patterns observed experimentally. The buckling instability of individual filaments is found to play a key role in localizing collapse events due to local force imbalance. Motor-driven buckling-induced node aggregation provides a dynamic mechanism that stabilizes the two-dimensional patterns below the apparent static percolation limit. Coordinated motor action is also shown to suppress random thermal noise on large time scales, the two-dimensional configuration that the system starts with thus remaining planar during the structural development. By carrying out similar simulations on a three-dimensional anchored network, we find that the myosin-driven isotropic contraction of a well-connected actin network, when combined with mechanical anchoring that confers directionality to the collective motion, may represent a novel mechanism of intracellular transport, as revealed by chromosome translocation in the starfish oocyte.

  20. Spatial patterns of microbial diversity and activity in an aged creosote-contaminated site

    PubMed Central

    Mukherjee, Shinjini; Juottonen, Heli; Siivonen, Pauli; Lloret Quesada, Cosme; Tuomi, Pirjo; Pulkkinen, Pertti; Yrjälä, Kim

    2014-01-01

    Restoration of polluted sites via in situ bioremediation relies heavily on the indigenous microbes and their activities. Spatial heterogeneity of microbial populations, contaminants and soil chemical parameters on such sites is a major hurdle in optimizing and implementing an appropriate bioremediation regime. We performed a grid-based sampling of an aged creosote-contaminated site followed by geostatistical modelling to illustrate the spatial patterns of microbial diversity and activity and to relate these patterns to the distribution of pollutants. Spatial distribution of bacterial groups unveiled patterns of niche differentiation regulated by patchy distribution of pollutants and an east-to-west pH gradient at the studied site. Proteobacteria clearly dominated in the hot spots of creosote pollution, whereas the abundance of Actinobacteria, TM7 and Planctomycetes was considerably reduced from the hot spots. The pH preferences of proteobacterial groups dominating in pollution could be recognized by examining the order and family-level responses. Acidobacterial classes came across as generalists in hydrocarbon pollution whose spatial distribution seemed to be regulated solely by the pH gradient. Although the community evenness decreased in the heavily polluted zones, basal respiration and fluorescein diacetate hydrolysis rates were higher, indicating the adaptation of specific indigenous microbial populations to hydrocarbon pollution. Combining the information from the kriged maps of microbial and soil chemistry data provided a comprehensive understanding of the long-term impacts of creosote pollution on the subsurface microbial communities. This study also highlighted the prospect of interpreting taxa-specific spatial patterns and applying them as indicators or proxies for monitoring polluted sites. PMID:25105905

  1. Spatial patterns of microbial diversity and activity in an aged creosote-contaminated site.

    PubMed

    Mukherjee, Shinjini; Juottonen, Heli; Siivonen, Pauli; Lloret Quesada, Cosme; Tuomi, Pirjo; Pulkkinen, Pertti; Yrjälä, Kim

    2014-10-01

    Restoration of polluted sites via in situ bioremediation relies heavily on the indigenous microbes and their activities. Spatial heterogeneity of microbial populations, contaminants and soil chemical parameters on such sites is a major hurdle in optimizing and implementing an appropriate bioremediation regime. We performed a grid-based sampling of an aged creosote-contaminated site followed by geostatistical modelling to illustrate the spatial patterns of microbial diversity and activity and to relate these patterns to the distribution of pollutants. Spatial distribution of bacterial groups unveiled patterns of niche differentiation regulated by patchy distribution of pollutants and an east-to-west pH gradient at the studied site. Proteobacteria clearly dominated in the hot spots of creosote pollution, whereas the abundance of Actinobacteria, TM7 and Planctomycetes was considerably reduced from the hot spots. The pH preferences of proteobacterial groups dominating in pollution could be recognized by examining the order and family-level responses. Acidobacterial classes came across as generalists in hydrocarbon pollution whose spatial distribution seemed to be regulated solely by the pH gradient. Although the community evenness decreased in the heavily polluted zones, basal respiration and fluorescein diacetate hydrolysis rates were higher, indicating the adaptation of specific indigenous microbial populations to hydrocarbon pollution. Combining the information from the kriged maps of microbial and soil chemistry data provided a comprehensive understanding of the long-term impacts of creosote pollution on the subsurface microbial communities. This study also highlighted the prospect of interpreting taxa-specific spatial patterns and applying them as indicators or proxies for monitoring polluted sites. PMID:25105905

  2. Parent Involvement in School-Related Activities.

    ERIC Educational Resources Information Center

    National Center for Education Statistics (ED), Washington, DC.

    Noting that some schools have adopted practices or policies that encourage parents to become more involved in their children's school activities and events, this statistical report (based on the National Household Education Survey) details the level and character of parental involvement in school activities. Findings highlighted are: (1) parents…

  3. Projections of Seasonal Patterns in Temperature- Related Deaths for Manhattan, New York

    NASA Technical Reports Server (NTRS)

    Li, Tiantian; Horton, Radley M.; Kinney, Patrick L.

    2013-01-01

    Global average temperatures have been rising for the past half-century, and the warming trend has accelerated in recent decades. Further warming is expected over the next few decades, with significant regional variations. These warming trends will probably result in more frequent, intense and persistent periods of hot temperatures in summer, and generally higher temperatures in winter. Daily death counts in cities increase markedly when temperatures reach levels that are very high relative to what is normal in a given location. Relatively cold temperatures also seem to carry risk. Rising temperatures may result in more heat-related mortality but may also reduce cold-related mortality, and the net impact on annual mortality remains uncertain. Here we use 16 downscaled global climate models and two emissions scenarios to estimate present and future seasonal patterns in temperature-related mortality in Manhattan, New York. All 32 projections yielded warm-season increases and cold-season decreases in temperature-related mortality, with positive net annual temperature-related deaths in all cases. Monthly analyses showed that the largest percentage increases may occur in May and September. These results suggest that, over a range of models and scenarios of future greenhouse gas emissions, increases in heat-related mortality could outweigh reductions in cold-related mortality, with shifting seasonal patterns.

  4. Large-scale phytogeographical patterns in eastern Asia in relation to latitudinal and climatic gradients

    USGS Publications Warehouse

    Qian, H.; Song, J.-S.; Krestov, P.; Guo, Q.; Wu, Z.; Shen, X.; Guo, X.

    2003-01-01

    This paper aims at determining how different floristic elements (e.g. cosmopolitan, tropical, and temperate) change with latitude and major climate factors, and how latitude affects the floristic relationships between East Asia and the other parts of the world. The large-scale patterns of phytogeography in East Asia are strongly related to latitude, which covaries with several climatic variables such as temperature. Evolutionary processes such as the adaptation of plants to cold climates and current and past land connections are likely responsible for the observed latitudinal patterns.

  5. Classroom Activities for Introducing Equivalence Relations

    ERIC Educational Resources Information Center

    Brandt, Jim

    2013-01-01

    Equivalence relations and partitions are two interconnected ideas that play important roles in advanced mathematics. While students encounter the informal notion of equivalence in many courses, the formal definition of an equivalence relation is typically introduced in a junior level transition-to-proof course. This paper reports the results of a…

  6. Altered lower leg muscle activation patterns in patients with cerebral palsy during cycling on an ergometer

    PubMed Central

    Alves-Pinto, Ana; Blumenstein, Tobias; Turova, Varvara; Lampe, Renée

    2016-01-01

    Objective Cycling on a recumbent ergometer constitutes one of the most popular rehabilitation exercises in cerebral palsy (CP). However, no control is performed on how muscles are being used during training. Given that patients with CP present altered muscular activity patterns during cycling or walking, it is possible that an incorrect pattern of muscle activation is being promoted during rehabilitation cycling. This study investigated patterns of muscular activation during cycling on a recumbent ergometer in patients with CP and whether those patterns are determined by the degree of spasticity and of mobility. Methods Electromyographic (EMG) recordings of lower leg muscle activation during cycling on a recumbent ergometer were performed in 14 adult patients diagnosed with CP and five adult healthy participants. EMG recordings were done with an eight-channel EMG system built in the laboratory. The activity of the following muscles was recorded: Musculus rectus femoris, Musculus biceps femoris, Musculus tibialis anterior, and Musculus gastrocnemius. The degree of muscle spasticity and mobility was assessed using the Modified Ashworth Scale and the Gross Motor Function Classification System, respectively. Muscle activation patterns were described in terms of onset and duration of activation as well as duration of cocontractions. Results Muscle activation in CP was characterized by earlier onsets, longer periods of activation, a higher occurrence of agonist–antagonist cocontractions, and a more variable cycling tempo in comparison to healthy participants. The degree of altered muscle activation pattern correlated significantly with the degree of spasticity. Conclusion This study confirmed the occurrence of altered lower leg muscle activation patterns in patients with CP during cycling on a recumbent ergometer. There is a need to develop feedback systems that can inform patients and therapists of an incorrect muscle activation during cycling and support the training

  7. Determining phase relations of proxy data using the eccentricity-precession pattern

    NASA Astrophysics Data System (ADS)

    Zeeden, C.; Rivera, T. A.

    2012-04-01

    The phase relation between proxy data and orbital forcing is not always obvious; a link to both precession/insolation maxima or -minima can often be reasoned for. We present a novel approach to extract the phase relation using solely eccentricity-precession pattern from high quality proxy data. We determine the position of consecutive eccentricity maxima as precisely as possible from a stratigraphic record using both eccentricity filters and the amplitude modulation of precession. This way we obtain both the position of these eccentricity maxima as well as the sedimentation rate between successive maxima with error margins. Combining these results with the precession pattern in the geological record, we can determine whether precession-related patterns relate to precession (or insolation) minima or maxima. This approach relies on high quality geological data, the assumption of a direct eccentricity and precession response to orbital forcing, and a well defined orbital solution, but avoids the assumption of an instantaneous response to obliquity. For data with filtered components showing a good fit with the proxy data, this approach yields good results. Using high quality proxy data (color, magnetic susceptibility), we are able to determine the phase relation for equatorial Atlantic Miocene successions of ODP Leg 154. The research leading to these results has received funding from the [European Community's] Seventh Framework Programme ([FP7/2007-2013] under grant agreement n° [215458]. This research used data provided by IODP. Funding for this research was provided by NWO.

  8. Identification of abnormal motor cortex activation patterns in children with cerebral palsy by functional near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Khan, Bilal; Tian, Fenghua; Behbehani, Khosrow; Romero, Mario I.; Delgado, Mauricio R.; Clegg, Nancy J.; Smith, Linsley; Reid, Dahlia; Liu, Hanli; Alexandrakis, George

    2010-05-01

    We demonstrate the utility of functional near-infrared spectroscopy (fNIRS) as a tool for physicians to study cortical plasticity in children with cerebral palsy (CP). Motor cortex activation patterns were studied in five healthy children and five children with CP (8.4+/-2.3 years old in both groups) performing a finger-tapping protocol. Spatial (distance from center and area difference) and temporal (duration and time-to-peak) image metrics are proposed as potential biomarkers for differentiating abnormal cortical activation in children with CP from healthy pediatric controls. In addition, a similarity image-analysis concept is presented that unveils areas that have similar activation patterns as that of the maximum activation area, but are not discernible by visual inspection of standard activation images. Metrics derived from the images presenting areas of similarity are shown to be sensitive identifiers of abnormal activation patterns in children with CP. Importantly, the proposed similarity concept and related metrics may be applicable to other studies for the identification of cortical activation patterns by fNIRS.

  9. Identification of abnormal motor cortex activation patterns in children with cerebral palsy by functional near-infrared spectroscopy

    PubMed Central

    Khan, Bilal; Tian, Fenghua; Behbehani, Khosrow; Romero, Mario I.; Delgado, Mauricio R.; Clegg, Nancy J.; Smith, Linsley; Reid, Dahlia; Liu, Hanli; Alexandrakis, George

    2010-01-01

    We demonstrate the utility of functional near-infrared spectroscopy (fNIRS) as a tool for physicians to study cortical plasticity in children with cerebral palsy (CP). Motor cortex activation patterns were studied in five healthy children and five children with CP (8.4±2.3years old in both groups) performing a finger-tapping protocol. Spatial (distance from center and area difference) and temporal (duration and time-to-peak) image metrics are proposed as potential biomarkers for differentiating abnormal cortical activation in children with CP from healthy pediatric controls. In addition, a similarity image-analysis concept is presented that unveils areas that have similar activation patterns as that of the maximum activation area, but are not discernible by visual inspection of standard activation images. Metrics derived from the images presenting areas of similarity are shown to be sensitive identifiers of abnormal activation patterns in children with CP. Importantly, the proposed similarity concept and related metrics may be applicable to other studies for the identification of cortical activation patterns by fNIRS. PMID:20615010

  10. A Three-Dimensional Human Atrial Model with Fiber Orientation. Electrograms and Arrhythmic Activation Patterns Relationship

    PubMed Central

    Tobón, Catalina; Ruiz-Villa, Carlos A.; Heidenreich, Elvio; Romero, Lucia; Hornero, Fernando; Saiz, Javier

    2013-01-01

    The most common sustained cardiac arrhythmias in humans are atrial tachyarrhythmias, mainly atrial fibrillation. Areas of complex fractionated atrial electrograms and high dominant frequency have been proposed as critical regions for maintaining atrial fibrillation; however, there is a paucity of data on the relationship between the characteristics of electrograms and the propagation pattern underlying them. In this study, a realistic 3D computer model of the human atria has been developed to investigate this relationship. The model includes a realistic geometry with fiber orientation, anisotropic conductivity and electrophysiological heterogeneity. We simulated different tachyarrhythmic episodes applying both transient and continuous ectopic activity. Electrograms and their dominant frequency and organization index values were calculated over the entire atrial surface. Our simulations show electrograms with simple potentials, with little or no cycle length variations, narrow frequency peaks and high organization index values during stable and regular activity as the observed in atrial flutter, atrial tachycardia (except in areas of conduction block) and in areas closer to ectopic activity during focal atrial fibrillation. By contrast, cycle length variations and polymorphic electrograms with single, double and fragmented potentials were observed in areas of irregular and unstable activity during atrial fibrillation episodes. Our results also show: 1) electrograms with potentials without negative deflection related to spiral or curved wavefronts that pass over the recording point and move away, 2) potentials with a much greater proportion of positive deflection than negative in areas of wave collisions, 3) double potentials related with wave fragmentations or blocking lines and 4) fragmented electrograms associated with pivot points. Our model is the first human atrial model with realistic fiber orientation used to investigate the relationship between different

  11. Activation of the human sensorimotor cortex during error-related processing: a magnetoencephalography study.

    PubMed

    Stemmer, Brigitte; Vihla, Minna; Salmelin, Riitta

    2004-05-13

    We studied error-related processing using magnetoencephalography (MEG). Previous event-related potential studies have documented error negativity or error-related negativity after incorrect responses, with a suggested source in the anterior cingulate cortex or supplementary motor area. We compared activation elicited by correct and incorrect trials using auditory and visual choice-reaction time tasks. Source areas showing different activation patterns in correct and error conditions were mainly located in sensorimotor areas, both ipsi- and contralateral to the response, suggesting that activation of sensorimotor circuits accompanies error processing. Additional activation at various other locations suggests a distributed network of brain regions active during error-related processing. Activation specific to incorrect trials tended to occur later in MEG than EEG data, possibly indicating that EEG and MEG detect different neural networks involved in error-related processes. PMID:15147777

  12. Patterns and origin of igneous activity around the Tanzanian craton

    NASA Astrophysics Data System (ADS)

    Foley, S. F.; Link, K.; Tiberindwa, J. V.; Barifaijo, E.

    2012-01-01

    Tertiary and later igneous activity is common on and around the Tanzanian craton, with primitive magma compositions ranging from kimberlites and varieties of picrites through nephelinites, basanites and alkali basalts. This review focuses on elucidating the conditions of origin of the melts, addressing the question of the state and involvement of the Tanzanian cratonic lithosphere in magma genesis. The Tanzanian craton is anomalous with a surface elevation of >1100 m reflecting buoyancy supported by a subcratonic plume whose effects are seen in the volcanics of both western and eastern rift branches. Magmatism on the craton and at its edge has high K/Na and primitive melts show fractionation dominated by olivine. Slightly further from the craton pyroxene fractionation dominates and K/Na ratios in the magmas are lower. Off-craton melts are nephelinites, basanites and alkali basalts with low K/Na. Potassium enrichment in the melts correlates with the occurrence of phlogopite in mantle-derived xenoliths, and also with carbonate in the magmas. This is attributed to melting at >140 km depths of mixed source regions containing phlogopite pyroxenite and peridotite, whereby the carbonate is derived from oxidation of diamonds concentrated near the base of the cratonic lithosphere. Mixed source regions are required by arrays of radiogenic isotopes such as Os and Sr in the volcanic rocks. The temporal progression of lamproites to phlogopite + carbonate-rich rocks to melilitites, nephelinites and alkali basalts seen during the erosion of the North Atlantic craton are seen around the Tanzanian craton as the coeval occurrence kimberlites, kamafugites and related rocks, nephelinites and alkali basalts showing spatial instead of temporal variation. This is due to the different stages of development of rifting around the craton: in northwestern Uganda and northern Tanzania, K-rich volcanism occurs at the craton edge, whereas nephelinites, basanites and alkali basalts occur where

  13. Learning a Taxonomy of Predefined and Discovered Activity Patterns

    PubMed Central

    Krishnan, Narayanan; Cook, Diane J.; Wemlinger, Zachary

    2013-01-01

    Many intelligent systems that focus on the needs of a human require information about the activities that are being performed by the human. At the core of this capability is activity recognition. Activity recognition techniques have become robust but rarely scale to handle more than a few activities. They also rarely learn from more than one smart home data set because of inherent differences between labeling techniques. In this paper we investigate a data-driven approach to creating an activity taxonomy from sensor data found in disparate smart home datasets. We investigate how the resulting taxonomy can help analyze the relationship between classes of activities. We also analyze how the taxonomy can be used to scale activity recognition to a large number of activity classes and training datasets. We describe our approach and evaluate it on 34 smart home datasets. The results of the evaluation indicate that the hierarchical modeling can reduce training time while maintaining accuracy of the learned model. PMID:25302084

  14. Learning a Taxonomy of Predefined and Discovered Activity Patterns.

    PubMed

    Krishnan, Narayanan; Cook, Diane J; Wemlinger, Zachary

    2013-01-01

    Many intelligent systems that focus on the needs of a human require information about the activities that are being performed by the human. At the core of this capability is activity recognition. Activity recognition techniques have become robust but rarely scale to handle more than a few activities. They also rarely learn from more than one smart home data set because of inherent differences between labeling techniques. In this paper we investigate a data-driven approach to creating an activity taxonomy from sensor data found in disparate smart home datasets. We investigate how the resulting taxonomy can help analyze the relationship between classes of activities. We also analyze how the taxonomy can be used to scale activity recognition to a large number of activity classes and training datasets. We describe our approach and evaluate it on 34 smart home datasets. The results of the evaluation indicate that the hierarchical modeling can reduce training time while maintaining accuracy of the learned model. PMID:25302084

  15. Identification of disease-related spatial covariance patterns using neuroimaging data.

    PubMed

    Spetsieris, Phoebe; Ma, Yilong; Peng, Shichun; Ko, Ji Hyun; Dhawan, Vijay; Tang, Chris C; Eidelberg, David

    2013-01-01

    The scaled subprofile model (SSM)(1-4) is a multivariate PCA-based algorithm that identifies major sources of variation in patient and control group brain image data while rejecting lesser components (Figure 1). Applied directly to voxel-by-voxel covariance data of steady-state multimodality images, an entire group image set can be reduced to a few significant linearly independent covariance patterns and corresponding subject scores. Each pattern, termed a group invariant subprofile (GIS), is an orthogonal principal component that represents a spatially distributed network of functionally interrelated brain regions. Large global mean scalar effects that can obscure smaller network-specific contributions are removed by the inherent logarithmic conversion and mean centering of the data(2,5,6). Subjects express each of these patterns to a variable degree represented by a simple scalar score that can correlate with independent clinical or psychometric descriptors(7,8). Using logistic regression analysis of subject scores (i.e. pattern expression values), linear coefficients can be derived to combine multiple principal components into single disease-related spatial covariance patterns, i.e. composite networks with improved discrimination of patients from healthy control subjects(5,6). Cross-validation within the derivation set can be performed using bootstrap resampling techniques(9). Forward validation is easily confirmed by direct score evaluation of the derived patterns in prospective datasets(10). Once validated, disease-related patterns can be used to score individual patients with respect to a fixed reference sample, often the set of healthy subjects that was used (with the disease group) in the original pattern derivation(11). These standardized values can in turn be used to assist in differential diagnosis(12,13) and to assess disease progression and treatment effects at the network level(7,14-16). We present an example of the application of this methodology to

  16. Using a Single-Item Physical Activity Measure to Describe and Validate Parents' Physical Activity Patterns

    ERIC Educational Resources Information Center

    Hamilton, Kyra; White, Katherine M.; Cuddihy, Tom

    2012-01-01

    The accurate measurement of health-related physical activity (PA), often interpreted as either 150 min/week of at least moderate-intensity PA (U.S. Department of Health and Human Services, 2008) or at least 30 min of at least moderate-intensity PA on 5 or more days per week (Australian Government Department of Health and Ageing [AGDHA], 2005;…

  17. Activity Patterns in Latissimus Dorsi and Sternocleidomastoid in Classical Singers

    PubMed Central

    Watson, Alan H.D.; Williams, Caitlin; James, Buddug V.

    2012-01-01

    Summary Objectives The aim of this study was to investigate and compare the roles of the accessory respiratory muscles, latissimus dorsi (LD), and sternocleidomastoid, in classical singing. Methods Electromyography was used to record the activity of these muscles in six classically trained female singers carrying out a number of singing and nonsinging tasks. Movements of the chest and abdominal walls were monitored simultaneously using inductive plethysmography, and the sound of the phonations was recorded. Results In normal breathing, LD is active transiently during very deep inhalations and in inhalation against resistance. During exhalation it becomes active again as residual capacity is approached or when air is expelled with great force. Sternocleidomastoid (SCM) supports inhalation when lung volume nears 100% vital capacity or when this is very rapid. All singers engaged LD in supported singing where it was associated with maintaining an expanded thorax. In coloratura singing, pulses of activity of increasing amplitude were often seen in LD toward the end of the breath. These were synchronized with each note. During a short phrase typical of the end of an aria, which was sung at full volume with the projected voice, both LD and SCM were active simultaneously. Spectral analysis of muscle activity demonstrated that in some singers, activity in LD and more rarely SCM, fluctuated in phase with vibrato. Conclusions LD appears to play a significant role in maintaining chest expansion and the dynamic processes underlying vibrato and coloratura singing in classically trained singers. PMID:21724365

  18. Patterns of acoustical activity of bats prior to and following White-nose Syndrome occurrence

    USGS Publications Warehouse

    Ford, W. Mark; Britzke, Eric R.; Dobony, Christopher A.; Rodrigue, Jane L.; Johnson, Joshua B.

    2011-01-01

    White-nose Syndrome (WNS), a wildlife health concern that has decimated cave-hibernating bat populations in eastern North America since 2006, began affecting source-caves for summer bat populations at Fort Drum, a U.S. Army installation in New York in the winter of 2007–2008. As regional die-offs of bats became evident, and Fort Drum's known populations began showing declines, we examined whether WNS-induced change in abundance patterns and seasonal timing of bat activity could be quantified using acoustical surveys, 2003–2010, at structurally uncluttered riparian–water habitats (i.e., streams, ponds, and wet meadows). As predicted, we observed significant declines in overall summer activity between pre-WNS and post-WNS years for little brown bats Myotis lucifugus, northern bats M. septentrionalis, and Indiana bats M. sodalis. We did not observe any significant change in activity patterns between pre-WNS and post-WNS years for big brown bats Eptesicus fuscus, eastern red bats Lasiurus borealis, or the small number of tri-colored bats Perimyotis subflavus. Activity of silver-haired bats Lasionycteris noctivagans increased from pre-WNS to post-WNS years. Activity levels of hoary bats Lasiurus cinereus significantly declined between pre- and post-WNS years. As a nonhibernating, migratory species, hoary bat declines might be correlated with wind-energy development impacts occurring in the same time frame rather than WNS. Intraseason activity patterns also were affected by WNS, though the results were highly variable among species. Little brown bats showed an overall increase in activity from early to late summer pre-WNS, presumably due to detections of newly volant young added to the local population. However, the opposite occurred post-WNS, indicating that reproduction among surviving little brown bats may be declining. Our data suggest that acoustical monitoring during the summer season can provide insights into species' relative abundance on the

  19. On the Relation between Jumping Emerging Patterns and Rough Set Theory with Application to Data Classification

    NASA Astrophysics Data System (ADS)

    Terlecki, Paweı

    Contrast patterns are an essential element of classification methods based on data mining. Among many propositions, jumping emerging patterns (JEPs) have gained significant recognition due to their simplicity and strong discrimination capabilities. This thesis considers JEPs in terms of discovery and classification. The focus is put on their correspondence to the rough set theory. Transformations between transactional data and decision tables allow us to demonstrate relations of JEPs and global/local reducts. As a part of this discussion, we introduce the concept of a jumping emerging pattern with negation (JEPN). Our observations lead to two novel JEP mining methods based on local reducts: global condensation and local projection. Both attempt to decrease dimensionality of subproblems prior to reduct computation. We show that JEP mining can be reduced to the reduct set problem. The latter is addressed with a new approach, called RedApriori, that follows an Apriori candidate generation scheme and employs pruning based on the notion of attribute set dependence. In addition, we discuss different ways of storing pattern collections and propose a CC-Trie, a tree structure that ensures compactness of information and fast pattern lookups.

  20. Helium-3 emission related to volcanic activity

    SciTech Connect

    Sano, Y.; Nakamura, Y.; Wakita, H.; Urabe, A.; Tominaga, T.

    1984-04-13

    The helium-3/helium-4 ratio in bubbling gases from ten hot springs located around Mount Ontake, an active volcano in central Japan, ranges from 1.71 R/sub atm/ (1.71 times the atmospheric ratio of 1.40 x 10/sup -6/) to 6.15 R/sub atm/. The value of the ratio decreases with distance from the central cone of the volcano. Such a tendency may be a characteristic of helium-3 emission in volcanic areas and suggests more primitive helium-3 is carried with fluid flowing through a conduit during volcanic activity. 6 references, 1 figure, 1 table.

  1. The anatomical relationships between the avian eye, orbit and sclerotic ring: implications for inferring activity patterns in extinct birds

    PubMed Central

    Hall, Margaret I

    2008-01-01

    Activity pattern, or the time of day when an animal is awake and active, is highly associated with that animal's ecology. There are two principal activity patterns: diurnal, or awake during the day in a photopic, or high light level, environment; and nocturnal, awake at night in scotopic, or low light level, conditions. Nocturnal and diurnal birds exhibit characteristic eye shapes associated with their activity pattern, with nocturnal bird eyes optimized for visual sensitivity with large corneal diameters relative to their eye axial lengths, and diurnal birds optimized for visual acuity, with larger axial lengths of the eye relative to their corneal diameters. The current study had three aims: (1) to quantify the nature of the relationship between the avian eye and its associated bony anatomy, the orbit and the sclerotic ring; (2) to investigate how activity pattern is reflected in that bony anatomy; and (3) to identify how much bony anatomy is required to interpret activity pattern reliably for a bird that does not have the soft tissue available for study, specifically, for a fossil. Knowledge of extinct avian activity patterns would be useful in making palaeoecological interpretations. Here eye, orbit and sclerotic ring morphologies of 140 nocturnal and diurnal bird species are analysed in a phylogenetic context. Although there is a close relationship between the avian eye and orbit, activity pattern can only be reliably interpreted for bony-only specimens, such as a fossil, that include both measurements of the sclerotic ring and orbit depth. Any missing data render the fossil analysis inaccurate, including fossil specimens that are flat and therefore do not have an orbit depth available. For example, activity pattern cannot be determined with confidence for Archaeopteryx lithographica, which has a complete sclerotic ring but no orbit depth measurement. Many of the bird fossils currently available that retain a good sclerotic ring tend to be flat specimens

  2. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns

    PubMed Central

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  3. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns.

    PubMed

    Xu, Sarah C; Gauthier, Angela C; Liu, Ji

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  4. Is geographic variation within species related to macroevolutionary patterns between species?

    PubMed

    Fisher-Reid, M C; Wiens, J J

    2015-08-01

    The relationship between microevolution and macroevolution is a central topic in evolutionary biology. An aspect of this relationship that remains very poorly studied in modern evolutionary biology is the relationship between within-species geographic variation and among-species patterns of trait variation. Here, we tested the relationship between climate and morphology among and within species in the salamander genus Plethodon. We focus on a discrete colour polymorphism (presence and absence of a red dorsal stripe) that appears to be related to climatic distributions in a common, wide-ranging species (Plethodon cinereus). We find that this trait has been variable among (and possibly within) species for >40 million years. Furthermore, we find a strong relationship among species between climatic variation and within-species morph frequencies. These between-species patterns are similar (but not identical) to those in the broadly distributed Plethodon cinereus. Surprisingly, there are no significant climate-morphology relationships within most other polymorphic species, despite the strong between-species patterns. Overall, our study provides an initial exploration of how within-species geographic variation and large-scale macroevolutionary patterns of trait variation may be related. PMID:26079479

  5. Not just couch potatoes or gym rats: alternative non-labor market time use patterns are associated with meeting physical activity guidelines among sedentary full-time employees

    PubMed Central

    Smith, Lindsey P.; Ng, Shu Wen; Popkin, Barry M.

    2014-01-01

    Physical activity and inactivity have distinct cardio-metabolic consequences, suggesting that combinations of activities can impact health above and beyond the effects of a single activity. However, little work has examined patterns of non-labor market time activity in the US population, particularly among full-time employees in sedentary occupations, who are at increased risk of adverse health consequences associated with a sedentary lifestyle. Identification of these patterns, and how they are related to total physical activity levels, is important for developing effective, attainable physical activity recommendations among sedentary employees, who typically have less time available for exercise. This is, especially the case for low-income employees who face the highest time and financial barriers to achieving physical activity goals. This study uses cluster analysis to examine patterns of non-labor market time use among full-time (≥40 h/week) employed adults in sedentary occupations (<3 MET-h) on working days in the American Time Use Study. We then examine whether these patterns are associated with higher likelihood of meeting physical activity recommendations and higher overall physical activity (MET-h). We find that non-labor market time use patterns include those characterized by screen activities, housework, caregiving, sedentary leisure, and exercise. For both genders, the screen pattern was the most common and increased from 2003 to 2012, while the exercise pattern was infrequent and consistent across time. Screen, sedentary leisure, and community patterns were associated with lower likelihoods of meeting physical activity recommendations, suggesting that interventions targeting screen time may miss opportunities to improve physical activity among similarly sedentary groups. Alternately, non-labor market time use patterns characterized by housework and caregiving, represented feasible avenues for increasing overall physical activity levels, especially

  6. Role of synaptic inhibition in spatiotemporal patterning of cortical activity.

    PubMed

    Bosman, Laurens; Lodder, Johannes C; van Ooyen, Arjen; Brussaard, Arjen B

    2005-01-01

    Developmental upregulation of the GABAA receptor alpha1 subunit causes a faster decay of GABAergic inhibitory postsynaptic currents (IPSCs) in the visual cortex around the time of eye opening. In alpha1 deficient mice, a juvenile type of GABAA receptors is retained during maturation. As a result the decay time of the IPSCs is longer in alpha1-/- mice than in WT mice during the whole life span of the mice. Hence they form a valuable mouse model for studies on cellular aspects of neuronal network functioning. Using voltage sensitive dye imaging methods, we monitored the spatiotemporal excitation patterning in visual cortex slices upon local stimulation of the network. We found that in the alpha1-/- mice, the ability of the network to fire synchronously at gamma-frequencies (20-50 Hz) is diminished. This finding indicates that early onset of GABA synapse maturation is required for the normal neuronal network function in the maturating visual cortex. PMID:15581707

  7. On the abundance and activity pattern of zoobenthos inhabiting a tropical reef area, Cebu, Philippines

    NASA Astrophysics Data System (ADS)

    Faubel, A.

    1984-12-01

    A benthic faunal study was carried out in the tidal area of Mactan Island (Cebu, Philippines). The area was subdivided along a transect from the beach to the reef according to benthic assemblages. The sediments are largely composed of calcareous skeletal remains of the indigenous biota and surrounding calcareous rocks. The content of protein and carbohydrates of the sediment was estimated, providing an approximation of organic matter in terms of feeding efficiency. Total number of zoobenthos, both as regards the sediment samples and as to the epifaunal communities associated with seaweeds, is rather uniformly distributed justifying the 95% confidence level ( P>0.05). Distinct differences are apparent in abundance values of individual taxa. Although the study area showed the expected distribution pattern, with dominance of Nematoda (39%) living in sediment and Harpacticoida (36 66%) dwelling on Thalassia and algae, Polychaeta reveal a dominant attraction to both these habitats. The reasons for this phenomenon are discussed in relation to the absolute lack of macrofaunal predators The zoobenthos adjust their distribution and activity to fluctuating conditions of the environment. Light is mainly suggested as stimulating diel migration activities of the benthic fauna, moving upwards from the sediment to the algae and Thalassia during daytime. In a field experiment the zoobenthos was investigated for digestion activity over a diurnal cycle. The results reveal that feeding activity of zoobenthos follows a diel cycle showing maximum activity during the morning and evening obviously influenced by changes of light.

  8. Activity patterns in the Sahara Desert: an interpretation based on cross-sectional geometric properties.

    PubMed

    Nikita, Efthymia; Siew, Yun Ysi; Stock, Jay; Mattingly, David; Lahr, Marta Mirazón

    2011-11-01

    The Garamantian civilization flourished in modern Fezzan, Libya, between 900 BC and 500 AD, during which the aridification of the Sahara was well established. Study of the archaeological remains suggests a population successful at coping with a harsh environment of high and fluctuating temperatures and reduced water and food resources. This study explores the activity patterns of the Garamantes by means of cross-sectional geometric properties. Long bone diaphyseal shape and rigidity are compared between the Garamantes and populations from Egypt and Sudan, namely from the sites of Kerma, el-Badari, and Jebel Moya, to determine whether the Garamantian daily activities were more strenuous than those of other North African populations. Moreover, sexual dimorphism and bilateral asymmetry are assessed at an intra- and inter-population level. The inter-population comparisons showed the Garamantes not to be more robust than the comparative populations, suggesting that the daily Garamantian activities necessary for survival in the Sahara Desert did not generally impose greater loads than those of other North African populations. Sexual dimorphism and bilateral asymmetry in almost all geometric properties of the long limbs were comparatively low among the Garamantes. Only the lower limbs were significantly stronger among males than females, possibly due to higher levels of mobility associated with herding. The lack of systematic bilateral asymmetry in cross-sectional geometric properties may relate to the involvement of the population in bilaterally intensive activities or the lack of regular repetition of unilateral activities. PMID:21953517

  9. Monitoring volcanic activities using correlation patterns between infrasound and ground motion

    NASA Astrophysics Data System (ADS)

    Ichihara, M.; Takeo, M.; Yokoo, A.

    2012-04-01

    This paper presents a simple method to distinguish infrasonic signals from wind noise using a cross-correlation function of signals from a microphone and a co-located seismometer. The method makes use of a particular feature of the cross-correlation function of vertical ground motion generated by infrasound, and the infrasound itself. Contribution of wind noise to the correlation function is effectively suppressed by separating the microphone and the seismometer by several meters because the correlation length of wind noise is much shorter than wavelengths of infrasound. The method is tested with data from volcanoes, and demonstrates that the method effectively detects not only the main eruptions, but also minor activity generating weak infrasound hardly visible in the wave traces. In addition, the correlation function gives more information about volcanic activity than infrasound alone. The correlation pattern changes when the spectral feature of the infrasound and/or the seismic wave changes and the relative strength of infrasound and seismic wave changes, both of which are expected to be accompanied by change in eruptive activity. Therefore, a graphical presentation of temporal variation in the cross-correlation function enables to see qualitative changes of eruptive activities at a glance. This method is particularly useful when available sensors are limited, and will extend the utility of a single microphone and seismometer in monitoring and understanding volcanic activity. The method is used to analyze sequences of two recent eruptions of Asama and Shinmoe-dake volcanoes, Japan.

  10. Tuning the Biological Activity Profile of Antibacterial Polymers via Subunit Substitution Pattern

    PubMed Central

    2015-01-01

    Binary nylon-3 copolymers containing cationic and hydrophobic subunits can mimic the biological properties of host-defense peptides, but relationships between composition and activity are not yet well understood for these materials. Hydrophobic subunits in previously studied examples have been limited mostly to cycloalkane-derived structures, with cyclohexyl proving to be particularly promising. The present study evaluates alternative hydrophobic subunits that are isomeric or nearly isomeric with the cyclohexyl example; each has four sp3 carbons in the side chains. The results show that varying the substitution pattern of the hydrophobic subunit leads to relatively small changes in antibacterial activity but causes significant changes in hemolytic activity. We hypothesize that these differences in biological activity profile arise, at least in part, from variations among the conformational propensities of the hydrophobic subunits. The α,α,β,β-tetramethyl unit is optimal among the subunits we have examined, providing copolymers with potent antibacterial activity and excellent prokaryote vs eukaryote selectivity. Bacteria do not readily develop resistance to the new antibacterial nylon-3 copolymers. These findings suggest that variation in subunit conformational properties could be generally valuable in the development of synthetic polymers for biological applications. PMID:24601599

  11. Physical activity and sedentary activity patterns among children and adolescents: a latent class analysis approach

    PubMed Central

    Heitzler, Carrie; Lytle, Leslie; Erickson, Darin; Sirard, John; Barr-Anderson, Daheia; Story, Marry

    2010-01-01

    Background While much is known about the overall levels of physical activity and sedentary activity among youth, few studies have attempted to define clusters of such behaviors. The purpose of this study was to identify and describe unique classes of youth based on their participation in a variety of physical activity and sedentary behaviors. Methods Latent class analysis was used to characterize segments of youth based on patterns of self-reported and accelerometer-measured participation in 12 behaviors. Children and adolescents (N=720) from 6th–11th grade were included in the analysis. Differences in class membership were examined using multinomial logistic regression. Results Three distinct classes emerged for boys and girls. Among boys, the three classes were characterized as: (1) “Active” (42.1%), (2) “Sedentary” (24.9%), and (3) “Low Media/Moderate Activity” (33.0%). For girls, classes were: (1) “Active” (18.7%), (2) “Sedentary” (47.6%), and (3) “Low Media/Functional Activity” (33.7%). Significant differences were found between the classes for a number of demographic indicators including the proportion in each class who were classified as overweight or obese. Conclusions The behavioral profiles of the classes identified in this study can be used to suggest possible audience segments for intervention and to tailor strategies appropriately. PMID:21597117

  12. Relationship between BOLD amplitude and pattern classification of orientation-selective activity in the human visual cortex.

    PubMed

    Tong, Frank; Harrison, Stephenie A; Dewey, John A; Kamitani, Yukiyasu

    2012-11-15

    Orientation-selective responses can be decoded from fMRI activity patterns in the human visual cortex, using multivariate pattern analysis (MVPA). To what extent do these feature-selective activity patterns depend on the strength and quality of the sensory input, and might the reliability of these activity patterns be predicted by the gross amplitude of the stimulus-driven BOLD response? Observers viewed oriented gratings that varied in luminance contrast (4, 20 or 100%) or spatial frequency (0.25, 1.0 or 4.0 cpd). As predicted, activity patterns in early visual areas led to better discrimination of orientations presented at high than low contrast, with greater effects of contrast found in area V1 than in V3. A second experiment revealed generally better decoding of orientations at low or moderate as compared to high spatial frequencies. Interestingly however, V1 exhibited a relative advantage at discriminating high spatial frequency orientations, consistent with the finer scale of representation in the primary visual cortex. In both experiments, the reliability of these orientation-selective activity patterns was well predicted by the average BOLD amplitude in each region of interest, as indicated by correlation analyses, as well as decoding applied to a simple model of voxel responses to simulated orientation columns. Moreover, individual differences in decoding accuracy could be predicted by the signal-to-noise ratio of an individual's BOLD response. Our results indicate that decoding accuracy can be well predicted by incorporating the amplitude of the BOLD response into simple simulation models of cortical selectivity; such models could prove useful in future applications of fMRI pattern classification. PMID:22917989

  13. A New Method to Study Bat Activity Patterns

    SciTech Connect

    Carter, T.C.; Menzel, M.A.; Chapman, B.R.; Miller, K.V.; Lee, J.R.

    1999-01-01

    Discusses development of a method to use data loggers that are independent of the receiving system to record data on environmental conditions (temperature, light intensity, and relative humidity) as well as multiple inputs from a radiotransmitter.

  14. Relation of filling pattern to diastolic function in severe left ventricular disease.

    PubMed Central

    Ng, K S; Gibson, D G

    1990-01-01

    M mode and Doppler echocardiograms, apex cardiograms, and phonocardiograms were recorded in 50 patients with severe ventricular disease of varying aetiology to examine how left ventricular filling is disturbed by cavity dilatation. The size of the left ventricular cavity was increased in all with a mean (SD) transverse diameter of 7.2 (0.8) cm at end diastole and 6.3 (0.8) cm at end systole. All were in sinus rhythm and 35 had functional mitral regurgitation. In nine patients, in whom filling period was less than 170 ms, transmitral flow showed only a single peak, representing summation. In the remainder there was a strikingly bimodal distribution of filling pattern. In 12 the ventricle filled dominantly with atrial systole (A fillers). Isovolumic relaxation was long (75 (35) ms) and wall motion incoordinate; mitral regurgitation was present in only one. In most (29) the left ventricle filled predominantly during early diastole (E fillers). Mitral regurgitation, which was present in 26, was much more common than in the A fillers, while the isovolumic relaxation time (10 (24) ms) was much shorter and the normal phase relations between flow velocity and wall motion were lost. In 24 E fillers no atrial flow was detected. In four there was no evidence of any mechanical activity, suggesting "atrial failure". In 20, either the apex cardiogram or the mitral echogram showed an A wave, implying that atrial contraction had occurred but had failed to cause transmitral flow, showing that ventricular filling was fundamentally disturbed in late diastole. A series of discrete abnormalities of filling, beyond those shown by Doppler alone, could thus be detected in this apparently homogeneous patient group by a combination of non-invasive methods. The presence and nature of these abnormalities may shed light on underlying physiological disturbances. Images PMID:2337492

  15. Diurnal patterns in lightning activity over South America

    NASA Astrophysics Data System (ADS)

    Ávila, Eldo E.; Bürgesser, Rodrigo E.; Castellano, Nesvit E.; Nicora, M. Gabriela

    2015-04-01

    Satellite observations of lightning flash distribution data are used to examine the diurnal cycle of lightning activity over the tropical and subtropical regions of South America. A harmonic analysis is used to study the spatial variations in the peak and strength of diurnal lightning activity across this area. Results show that in the northern and central regions of South America, the times of maxima in lightning activity was concentrated from late afternoon to evening hours (between 14:00 and 18:00 local time), which may be associated with the peaking of the local convective activity connected with heating of the surface caused by daytime insolation. In subtropical South America, particularly in the area limited by 25°S, 35°S of latitude and 70°W, 50°W of longitude, the time of maximum lightning activity was shifted to nocturnal hours, extending from close to midnight to early morning hours. This behavior can be associated to the peak in mesoscale convective systems in the region which occurs in the morning hours. The annual flash densities in the tropical and subtropical parts of the continent were found to have comparable magnitudes. However, the contribution of the continental tropics to the global electric circuit dominates over the continental subtropics contribution throughout all seasons, since the surface covered by the tropical region is more than twice the area covered by the subtropical region.

  16. Patterns of arm muscle activation involved in octopus reaching movements.

    PubMed

    Gutfreund, Y; Flash, T; Fiorito, G; Hochner, B

    1998-08-01

    The extreme flexibility of the octopus arm allows it to perform many different movements, yet octopuses reach toward a target in a stereotyped manner using a basic invariant motor structure: a bend traveling from the base of the arm toward the tip (Gutfreund et al., 1996a). To study the neuronal control of these movements, arm muscle activation [electromyogram (EMG)] was measured together with the kinematics of reaching movements. The traveling bend is associated with a propagating wave of muscle activation, with maximal muscle activation slightly preceding the traveling bend. Tonic activation was occasionally maintained afterward. Correlation of the EMG signals with the kinematic variables (velocities and accelerations) reveals that a significant part of the kinematic variability can be explained by the level of muscle activation. Furthermore, the EMG level measured during the initial stages of movement predicts the peak velocity attained toward the end of the reaching movement. These results suggest that feed-forward motor commands play an important role in the control of movement velocity and that simple adjustment of the excitation levels at the initial stages of the movement can set the velocity profile of the whole movement. A simple model of octopus arm extension is proposed in which the driving force is set initially and is then decreased in proportion to arm diameter at the bend. The model qualitatively reproduces the typical velocity profiles of octopus reaching movements, suggesting a simple control mechanism for bend propagation in the octopus arm. PMID:9671683

  17. Geopolymers and Related Alkali-Activated Materials

    NASA Astrophysics Data System (ADS)

    Provis, John L.; Bernal, Susan A.

    2014-07-01

    The development of new, sustainable, low-CO2 construction materials is essential if the global construction industry is to reduce the environmental footprint of its activities, which is incurred particularly through the production of Portland cement. One type of non-Portland cement that is attracting particular attention is based on alkali-aluminosilicate chemistry, including the class of binders that have become known as geopolymers. These materials offer technical properties comparable to those of Portland cement, but with a much lower CO2 footprint and with the potential for performance advantages over traditional cements in certain niche applications. This review discusses the synthesis of alkali-activated binders from blast furnace slag, calcined clay (metakaolin), and fly ash, including analysis of the chemical reaction mechanisms and binder phase assemblages that control the early-age and hardened properties of these materials, in particular initial setting and long-term durability. Perspectives for future research developments are also explored.

  18. Is there any relationship between physical activity level and patterns, and physical performance in children?

    PubMed Central

    2011-01-01

    Background It is often assumed that physical activity (PA) and physical performance during childhood and adolescence are beneficial for health during adulthood, but a positive relationship between PA and physical performance has not been precisely clarified in children. The lack or the weakness of the relationships between PA and physical performance could be due to the measure of PA. If the use of accelerometry is considered as an objective and common measure of PA, the real patterns of children's habitual PA must be reflected. The aim of this study was to investigate the relationship between the levels and patterns of PA assessed with high frequency accelerometry and physical performance in young children. Methods Eighty-six boys and 101 girls aged 6-12 years participated in this study. Physical activity was measured over a 7-day period, using a 5-s epoch. Physical performance was assessed by means of EUROFIT tests (anthropometrics, standing broad jump, the 10 × 5 meter shuttle run, the sit-and-reach, the handgrip, the number of sit-ups in 30 seconds, the 20-meter shuttle run). Results No relationship was found between PA and physical performance. In boys only, body fatness was negatively associated with vigorous PA (r = -0.38, p < 0.001) and very high PA (r = -0.35, p < 0.01), in contrast to light PA (r = 0.28, p < 0.01), which was positively related to body fatness. Conclusion In 6- to- 12 year- old children, the more active children were not the fittest. Our results also underline the need for uniformity in approach to measurement of PA, body composition and health-related fitness between studies. PMID:22053790

  19. Spatiotemporal activity patterns of rat cortical neurons predict responses in a conditioned task

    PubMed Central

    Villa, Alessandro E. P.; Tetko, Igor V.; Hyland, Brian; Najem, Abdellatif

    1999-01-01

    Precise and repeated spike-train timings within and across neurons define spatiotemporal patterns of activity. Although the existence of these patterns in the brain is well established in several species, there has been no direct evidence of their influence on behavioral output. To address this question, up to 15 neurons were recorded simultaneously in the auditory cortex of freely moving rats while animals waited for acoustic cues in a Go/NoGo task. A total of 235 significant patterns were detected during this interval from an analysis of 13 hr of recording involving over 1 million spikes. Of particular interest were 129 (55%) patterns that were significantly associated with the type of response the animal made later, independent of whether the response was that prompted by the cue because the response occurred later and the cue was chosen randomly. Of these behavior-predicting patterns, half (59/129) were associated with an enhanced tendency to go in response to the stimulus, and for 11 patterns of this subset, trials including the pattern were followed by significantly faster reaction time than those lacking the pattern. The remaining behavior-predicting patterns were associated with an enhanced NoGo tendency. Overall mean discharge rates did not vary across trials. Hence, these data demonstrate that particular spatiotemporal patterns predict future behavioral responses. Such presignal activity could form templates for extracting specific sensory information, motor programs prespecifying preference for a particular act, and/or some intermediate, associative brain process. PMID:9927701

  20. Spatiotemporal Patterns of Schistosomiasis-Related Deaths, Brazil, 2000–2011

    PubMed Central

    Martins-Melo, Francisco Rogerlândio; Pinheiro, Marta Cristhiany Cunha; Ramos, Alberto Novaes; Alencar, Carlos Henrique; Bezerra, Fernando Schemelzer de Moraes

    2015-01-01

    We analyzed spatiotemporal patterns of 8,756 schistosomiasis-related deaths in Brazil during 2000–2011 and identified high-risk clusters of deaths, mainly in highly schistosomiasis-endemic areas along the coast of Brazil’s Northeast Region. Schistosomiasis remains a neglected public health problem with a high number of deaths in disease-endemic and emerging focal areas. PMID:26401716

  1. Behavioral orientations and peer-contact patterns of relationally aggressive girls.

    PubMed

    Isobe, Miyoshi; de Carvalho Filho, Moisés Kirk; Maeda, Kenichi

    2004-02-01

    The present study was designed to assess the behavioral orientations and peer-contact patterns of relationally aggressive girls. Based on teachers' assessments of relational aggression, 16 preschool girls were assigned to either a relationally aggressive group or a nonaggressive group and then observed in a free play setting. Several aspects of their interactive behaviors, e.g., cooperative play and social conversation, and noninteractive behaviors, e.g., solitary play and transition, were observed. Analysis indicated the relationally aggressive group spent more time engaged in social conversation and transition and less time in cooperative play than did the nonaggressive group. Further, findings indicated that the relationally aggressive group spent more time with one particular peer than did the nonaggressive group. PMID:15077786

  2. Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

    PubMed

    Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

    2016-09-01

    Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and

  3. Annual pattern of nitrate reductase activity in needles of high-elevation red spruce trees

    SciTech Connect

    Tjoelker, M.G.; Norby, R.J. ); DiCosty, R.J. ); Weerasuriya, Y. )

    1989-04-01

    To assess the ability of foliar nitrate reductase (NR) as a biochemical marker for the impact of nitrogen oxide pollutants on high-elevation forests, we measured needle NR activity in red spruce (Picea rubens Sarg.) saplings at two stands in the Great Smoky Mountains National Park (1,935 m, 1,720 m). Seven times between September 1987 and 1988, branches were cut from selected saplings, and NR activity was assayed on current-year needles, using an in vivo method. NR activity increased to maximum values of 60 nmol g{sup {minus}1} h{sup {minus}1} in late summer of both years and then declined by 85 percent in October 1987 and 65 percent in September 1988. Although NR activity was 30 percent great in red spruce at the high site relative to the low site in September and October 1987, NR activity dropped to 10 nmol g{sup {minus}1} h{sup {minus}1} at both sites in November 1987. No difference between the sites were evident in 1988. The seasonal pattern of needle NR activity at these sites may be due to ontogenetic changes in needle N metabolism and/or extrinsic variation in temperature or nitrogen oxide deposition. Characterization of nitrogen oxide pollutant levels and exposure episodes at high-elevation sites may aid in assessing seasonal and site variation in NR activity and the likelihood of needle NR induction by uptake of nitrogen oxides. These measurements of NR activity indicate that red spruce are capable of reducing nitrate in foliage under field conditions and that the nitrate assimilation capacity varies seasonally.

  4. The Influence of verbalization on the pattern of cortical activation during mental arithmetic

    PubMed Central

    2012-01-01

    Background The aim of the present functional magnetic resonance imaging (fMRI) study at 3 T was to investigate the influence of the verbal-visual cognitive style on cerebral activation patterns during mental arithmetic. In the domain of arithmetic, a visual style might for example mean to visualize numbers and (intermediate) results, and a verbal style might mean, that numbers and (intermediate) results are verbally repeated. In this study, we investigated, first, whether verbalizers show activations in areas for language processing, and whether visualizers show activations in areas for visual processing during mental arithmetic. Some researchers have proposed that the left and right intraparietal sulcus (IPS), and the left angular gyrus (AG), two areas involved in number processing, show some domain or modality specificity. That is, verbal for the left AG, and visual for the left and right IPS. We investigated, second, whether the activation in these areas implied in number processing depended on an individual's cognitive style. Methods 42 young healthy adults participated in the fMRI study. The study comprised two functional sessions. In the first session, subtraction and multiplication problems were presented in an event-related design, and in the second functional session, multiplications were presented in two formats, as Arabic numerals and as written number words, in an event-related design. The individual's habitual use of visualization and verbalization during mental arithmetic was assessed by a short self-report assessment. Results We observed in both functional sessions that the use of verbalization predicts activation in brain areas associated with language (supramarginal gyrus) and auditory processing (Heschl's gyrus, Rolandic operculum). However, we found no modulation of activation in the left AG as a function of verbalization. Conclusions Our results confirm that strong verbalizers use mental speech as a form of mental imagination more strongly than

  5. The BDNF Val66Met Polymorphism Influences Reading Ability and Patterns of Neural Activation in Children.

    PubMed

    Jasińska, Kaja K; Molfese, Peter J; Kornilov, Sergey A; Mencl, W Einar; Frost, Stephen J; Lee, Maria; Pugh, Kenneth R; Grigorenko, Elena L; Landi, Nicole

    2016-01-01

    Understanding how genes impact the brain's functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children's (age 6-10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading-related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes. PMID:27551971

  6. The BDNF Val66Met Polymorphism Influences Reading Ability and Patterns of Neural Activation in Children

    PubMed Central

    Jasińska, Kaja K.; Molfese, Peter J.; Kornilov, Sergey A.; Mencl, W. Einar; Frost, Stephen J.; Lee, Maria; Pugh, Kenneth R.; Grigorenko, Elena L.; Landi, Nicole

    2016-01-01

    Understanding how genes impact the brain’s functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children’s (age 6–10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading–related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes. PMID:27551971

  7. Use of a twin dataset to identify AMD-related visual patterns controlled by genetic factors

    NASA Astrophysics Data System (ADS)

    Quellec, Gwénolé; Abràmoff, Michael D.; Russell, Stephen R.

    2010-03-01

    The mapping of genotype to the phenotype of age-related macular degeneration (AMD) is expected to improve the diagnosis and treatment of the disease in a near future. In this study, we focused on the first step to discover this mapping: we identified visual patterns related to AMD which seem to be controlled by genetic factors, without explicitly relating them to the genes. For this purpose, we used a dataset of eye fundus photographs from 74 twin pairs, either monozygotic twins, who have the same genotype, or dizygotic twins, whose genes responsible for AMD are less likely to be identical. If we are able to differentiate monozygotic twins from dizygotic twins, based on a given visual pattern, then this pattern is likely to be controlled by genetic factors. The main visible consequence of AMD is the apparition of drusen between the retinal pigment epithelium and Bruch's membrane. We developed two automated drusen detectors based on the wavelet transform: a shape-based detector for hard drusen, and a texture- and color- based detector for soft drusen. Forty visual features were evaluated at the location of the automatically detected drusen. These features characterize the texture, the shape, the color, the spatial distribution, or the amount of drusen. A distance measure between twin pairs was defined for each visual feature; a smaller distance should be measured between monozygotic twins for visual features controlled by genetic factors. The predictions of several visual features (75.7% accuracy) are comparable or better than the predictions of human experts.

  8. Temporal-Spatial Neural Activation Patterns Linked to Perceptual Encoding of Emotional Salience

    PubMed Central

    Todd, Rebecca M.; Taylor, Margot J.; Robertson, Amanda; Cassel, Daniel B.; Doesberg, Sam M.; Lee, Daniel H.; Shek, Pang N.; Pang, Elizabeth W.

    2014-01-01

    It is well known that we continuously filter incoming sensory information, selectively allocating attention to what is important while suppressing distracting or irrelevant information. Yet questions remain about spatiotemporal patterns of neural processes underlying attentional biases toward emotionally significant aspects of the world. One index of affectively biased attention is an emotional variant of an attentional blink (AB) paradigm, which reveals enhanced perceptual encoding for emotionally salient over neutral stimuli under conditions of limited executive attention. The present study took advantage of the high spatial and temporal resolution of magnetoencephalography (MEG) to investigate neural activation related to emotional and neutral targets in an AB task. MEG data were collected while participants performed a rapid stimulus visual presentation task in which two target stimuli were embedded in a stream of distractor words. The first target (T1) was a number and the second (T2) either an emotionally salient or neutral word. Behavioural results replicated previous findings of greater accuracy for emotionally salient than neutral T2 words. MEG source analyses showed that activation in orbitofrontal cortex, characterized by greater power in the theta and alpha bands, and dorsolateral prefrontal activation were associated with successful perceptual encoding of emotionally salient relative to neutral words. These effects were observed between 250 and 550 ms, latencies associated with discrimination of perceived from unperceived stimuli. These data suggest that important nodes of both emotional salience and frontoparietal executive systems are associated with the emotional modulation of the attentional blink. PMID:24727751

  9. Prostate segmentation with local binary patterns guided active appearance models

    NASA Astrophysics Data System (ADS)

    Ghose, Soumya; Oliver, Arnau; Martí, Robert; Lladó, Xavier; Freixenet, Jordi; Vilanova, Joan C.; Meriaudeau, Fabrice

    2011-03-01

    Real-time fusion of Magnetic Resonance (MR) and Trans Rectal Ultra Sound (TRUS) images aid in the localization of malignant tissues in TRUS guided prostate biopsy. Registration performed on segmented contours of the prostate reduces computational complexity and improves the multimodal registration accuracy. However, accurate and computationally efficient segmentation of the prostate in TRUS images could be challenging in the presence of heterogeneous intensity distribution inside the prostate gland, and other imaging artifacts like speckle noise, shadow regions and low Signal to Noise Ratio (SNR). In this work, we propose to enhance the texture features of the prostate region using Local Binary Patterns (LBP) for the propagation of a shape and appearance based statistical model to segment the prostate in a multi-resolution framework. A parametric model of the propagating contour is derived from Principal Component Analysis (PCA) of the prior shape and texture information of the prostate from the training data. The estimated parameters are then modified with the prior knowledge of the optimization space to achieve an optimal segmentation. The proposed method achieves a mean Dice Similarity Coefficient (DSC) value of 0.94+/-0.01 and a mean segmentation time of 0.68+/-0.02 seconds when validated with 70 TRUS images of 7 datasets in a leave-one-patient-out validation framework. Our method performs computationally efficient and accurate prostate segmentation in the presence of intensity heterogeneities and imaging artifacts.

  10. Interfacial activity and leaching patterns of Leptospirillum ferrooxidans on pyrite.

    PubMed

    Rojas-Chapana, José A; Tributsch, Helmut

    2004-01-01

    The leaching ability of Leptospirillum ferrooxidans goes beyond the mere oxidation of Fe(2+) to Fe(3+). Addition of these bacteria to pyrite triggers interfacial phenomena that lead to bacterial attachment and local forms of corrosion (surface pitting). As the leaching process proceeds, bacterial cells undergo changes, characterized by the release of extracellular polymeric substances (EPS) and the uptake and storage of electro-dense nanoparticles. The latter are embedded in an exopolymeric capsule, which coats the bacterial surface leading to distinctive biomineralized assemblages. High-resolution scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses, quantitative energy-dispersive X-ray measurements and electron diffraction established that the embedded electron-dense nanoparticles comprise pyrite with a well-defined stoichiometry. Addition of Fe(3+) alone did not induce any form of local corrosion on pyrite, which indicates that the reactions taking place between the attached bacteria and the underlying pyrite surface are responsible for the leaching patterns observed in this study. The observed corrosion process resembles that of 'electrochemical machining', because it uses a corrosion promoter, namely the locally concentrated Fe(3+) in the biofilm environment, formed by the attached cells. PMID:19712343

  11. Sedimentary organic matter distributions, burrowing activity, and biogeochemical cycling: Natural patterns and experimental artifacts

    NASA Astrophysics Data System (ADS)

    Michaud, Emma; Aller, Robert, C.; Stora, Georges

    2010-11-01

    The coupling between biogenic reworking activity and reactive organic matter patterns within deposits is poorly understood and often ignored. In this study, we examined how common experimental treatments of sediment affect the burrowing behavior of the polychaete Nephtys incisa and how these effects may interact with reactive organic matter distributions to alter diagenetic transport - reaction balances. Sediment and animals were recovered from a subtidal site in central Long Island Sound, USA. The upper 15 cm of the sediment was sectioned into sub-intervals, and each interval separately sieved and homogenized. Three initial distributions of sediment and organic substrate reactivity were setup in a series of microcosms: (1) a reconstituted natural pattern with surface-derived sediment overlying sediment obtained from progressively deeper material to a depth of 15 cm (Natural); (2) a 15 cm thick sediment layer composed only of surface-derived sediment (Rich); and (3) a 15 cm thick layer composed of uniformally mixed sediment from the original 15 cm sediment profile (Averaged). The two last treatments are comparable to that used in microcosms in many previous studies of bioturbation and interspecific functional interaction experiments. Sediment grain size distributions were 97.5% silt-clay and showed no depth dependent patterns. Sediment porosity gradients were slightly altered by the treatments. Nepthys were reintroduced and aquariums were X-rayed regularly over 5 months to visualize and quantify spatial and temporal dynamics of burrows. The burrowing behaviour of adult populations having similar total biovolume, biomass, abundance, and individual sizes differed substantially as a function of treatment. Burrows in sediment with natural property gradients were much shallower and less dense than those in microcosms with altered gradients. The burrow volume/biovolume ratio was also lower in the substrate with natural organic reactivity gradients. Variation in food

  12. Emergent patterns from probabilistic generalizations of lateral activation and inhibition

    PubMed Central

    Kabla, Alexandre

    2016-01-01

    The combination of laterally activating and inhibiting feedbacks is well known to spontaneously generate spatial organization. It was introduced by Gierer and Meinhardt as an extension of Turing's great insight that two reacting and diffusing chemicals can spontaneously drive spatial morphogenesis per se. In this study, we develop an accessible nonlinear and discrete probabilistic model to study simple generalizations of lateral activation and inhibition. By doing so, we identify a range of modes of morphogenesis beyond the familiar Turing-type modes; notably, beyond stripes, hexagonal nets, pores and labyrinths, we identify labyrinthine highways, Kagome lattices, gyrating labyrinths and multi-colour travelling waves and spirals. The results are discussed within the context of Turing's original motivating interest: the mechanisms which underpin the morphogenesis of living organisms. PMID:27170648

  13. Patterns of Neural Activity in Networks with Complex Connectivity

    NASA Astrophysics Data System (ADS)

    Solla, Sara A.

    2008-03-01

    An understanding of emergent dynamics on complex networks requires investigating the interplay between the intrinsic dynamics of the node elements and the connectivity of the network in which they are embedded. In order to address some of these questions in a specific scenario of relevance to the dynamical states of neural ensembles, we have studied the collective behavior of excitable model neurons in a network with small-world topology. The small-world network has local lattice order, but includes a number of randomly placed connections that may provide connectivity shortcuts. This topology bears a schematic resemblance to the connectivity of the cerebral cortex, in which neurons are most strongly coupled to nearby cells within fifty to a hundred micrometers, but also make projections to cells millimeters away. We find that the dynamics of this small-world network of excitable neurons depend mostly on both the density of shortcuts and the delay associated with neuronal projections. In the regime of low shortcut density, the system exhibits persistent activity in the form of propagating waves, which annihilate upon collision and are spawned anew via the re-injection of activity through shortcut connections. As the density of shortcuts reaches a critical value, the system undergoes a transition to failure. The critical shortcut density results from matching the time associated with a recurrent path through the network to an intrinsic recovery time of the individual neurons. Furthermore, if the delay associated with neuronal interactions is sufficiently long, activity reemerges above the critical density of shortcuts. The activity in this regime exhibits long, chaotic transients composed of noisy, large-amplitude population bursts.

  14. 12 CFR 225.129 - Activities closely related to banking.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Activities closely related to banking. 225.129 Section 225.129 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL... Holding Companies Interpretations § 225.129 Activities closely related to banking. Courier activities....

  15. 29 CFR 780.122 - Activities relating to race horses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Activities relating to race horses. 780.122 Section 780.122... Activities relating to race horses. Employees engaged in the breeding, raising, and training of horses on..., employees engaged in the racing, training, and care of horses and other activities performed off the farm...

  16. 29 CFR 780.122 - Activities relating to race horses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Activities relating to race horses. 780.122 Section 780.122... Activities relating to race horses. Employees engaged in the breeding, raising, and training of horses on..., employees engaged in the racing, training, and care of horses and other activities performed off the farm...

  17. 29 CFR 780.122 - Activities relating to race horses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Activities relating to race horses. 780.122 Section 780.122... Activities relating to race horses. Employees engaged in the breeding, raising, and training of horses on..., employees engaged in the racing, training, and care of horses and other activities performed off the farm...

  18. 29 CFR 780.122 - Activities relating to race horses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Activities relating to race horses. 780.122 Section 780.122... Activities relating to race horses. Employees engaged in the breeding, raising, and training of horses on..., employees engaged in the racing, training, and care of horses and other activities performed off the farm...

  19. 29 CFR 780.122 - Activities relating to race horses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Activities relating to race horses. 780.122 Section 780.122... Activities relating to race horses. Employees engaged in the breeding, raising, and training of horses on..., employees engaged in the racing, training, and care of horses and other activities performed off the farm...

  20. The Afrocentric Paradigm in Health-Related Physical Activity.

    ERIC Educational Resources Information Center

    Pittman, Beverly D.

    2003-01-01

    Examines the potential role of culture in health-related physical activity participation, discussing kinesiology and reporting results from a health-related physical activity study of women, some of whom had taken a culturally designed aerobics class. Participants demonstrated the positive impact of culture on physical activity participation.…

  1. Language affects patterns of brain activation associated with perceptual decision.

    PubMed

    Tan, Li Hai; Chan, Alice H D; Kay, Paul; Khong, Pek-Lan; Yip, Lawrance K C; Luke, Kang-Kwong

    2008-03-11

    Well over half a century ago, Benjamin Lee Whorf [Carroll JB (1956) Language, Thought, and Reality: Selected Writings of Benjamin Lee Whorf (MIT Press, Cambridge, MA)] proposed that language affects perception and thought and is used to segment nature, a hypothesis that has since been tested by linguistic and behavioral studies. Although clear Whorfian effects have been found, it has not yet been demonstrated that language influences brain activity associated with perception and/or immediate postperceptual processes (referred hereafter as "perceptual decision"). Here, by using functional magnetic resonance imaging, we show that brain regions mediating language processes participate in neural networks activated by perceptual decision. When subjects performed a perceptual discrimination task on easy-to-name and hard-to-name colored squares, largely overlapping cortical regions were identified, which included areas of the occipital cortex critical for color vision and regions in the bilateral frontal gyrus. Crucially, however, in comparison with hard-to-name colored squares, perceptual discrimination of easy-to-name colors evoked stronger activation in the left posterior superior temporal gyrus and inferior parietal lobule, two regions responsible for word-finding processes, as demonstrated by a localizer experiment that uses an explicit color patch naming task. This finding suggests that the language-processing areas of the brain are directly involved in visual perceptual decision, thus providing neuroimaging support for the Whorf hypothesis. PMID:18316728

  2. Subjective and objective wine quality in Central Mediterranean in relation to large scale climate patterns

    NASA Astrophysics Data System (ADS)

    Baldi, Marina; Dalu, John David; Dalla Marta, Anna; Orlandini, Simone; Maracchi, Gianpiero; Dalu, Giovannangelo; Grifoni, Daniele; Mancini, Marco

    2013-04-01

    Subjective wine ranking is based on three factors: appearance (eye), smell (nose) and taste (palate); this kind of subjective ranking is often preferred over that based on technical objective means. Wine quality depends on its composition, which is a function of a number of factors: grapevine variety, soil type, cultivation techniques, and climate conditions. Between them, the soil is the main fixed factor; the positive trend is determined by a combination of improved cultural techniques and of warming related to climate change; while the climate variability is the main factor in determining the year-to-year wine quality variations. Therefore, the analysis of the grape composition before harvest is crucial for establishing the quality-climate correlations. In this work, 40 years of objective and subjective wine quality data collected in Italy are analyzed in relation to the climate conditions. Results show that the year-to-year quality variation of wines produced in North and Central Italy depends on the large scale climate variability, and that the wine quality improvement in the last four decades is partially due to an increase of temperature and to a decrease of the precipitations in West and Central Mediterranean Europe (WME; CME). In addition, wine quality is positively correlated with air temperature throughout the entire active period of the grapevine; weakly negatively correlated with precipitation in spring, and well negatively correlated in summer and fall. The month-to-month composites of the NAO anomaly show that, in years of good quality wine, this anomaly is negative in late spring, oscillates around zero in summer, and is positive in early fall; while, in years of bad quality wine, it is positive in late spring and summer, and negative in early fall; i.e. its polarity has an opposite sign in spring and fall in good versus bad years. The composite seasonal maps show that good wines are produced when the spring jet stream over Atlantic diverts most of

  3. Latent class analysis of alcohol treatment utilization patterns and 3-year alcohol related outcomes.

    PubMed

    Mowbray, Orion; Glass, Joseph E; Grinnell-Davis, Claudette L

    2015-07-01

    People who obtain treatment for alcohol use problems often utilize multiple sources of help. While prior studies have classified treatment use patterns for alcohol use, an empirical classification of these patterns is lacking. For the current study, we created an empirically derived classification of treatment use and described how these classifications were prospectively associated with alcohol-related outcomes. Our sample included 257 participants of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) who first received alcohol treatment in the 3-year period prior to their baseline interview. We used latent class analysis to identify classes of treatment users based on their patterns of treatment use of 13 types of alcohol treatment. Regression models examined how classes of treatment use at baseline were associated with alcohol-related outcomes assessed at a 3-year follow-up interview. Outcomes included a continuous measure of the quantity and frequency of alcohol use and DSM-IV alcohol use disorder status. Four classes of treatment users were identified: (1) multiservice users (8.7%), (2) private professional service users (32.8%), (3) alcoholics anonymous (AA) paired with specialty addiction service users (22.0%), and (4) users of AA alone (36.5%). Those who utilized AA paired with specialty addiction services had better outcomes compared to those who used AA alone. In addition to elucidating the most common treatment utilization patterns executed by people seeking help for their alcohol problems, the results from this study suggest that increased efforts may be needed to refer individuals across sectors of care to improve treatment outcomes. PMID:25744651

  4. Patterns of Brain Activation in Foster Children and Nonmaltreated Children During an Inhibitory Control Task

    PubMed Central

    Bruce, Jacqueline; Fisher, Philip A.; Graham, Alice M.; Moore, William E.; Peake, Shannon J.; Mannering, Anne M.

    2012-01-01

    Children in foster care have often encountered a range of adverse experiences, including neglectful and/or abusive care and multiple caregiver transitions. Prior research findings suggest that such experiences negatively affect inhibitory control and the underlying neural circuitry. In the current study, event-related functional magnetic resonance imaging (fMRI) was employed during a go/no go task that assesses inhibitory control to compare the behavioral performance and brain activation of foster children and nonmaltreated children. The sample included two groups of 9- to 12-year-old children: 11 maltreated foster children and 11 nonmaltreated children living with their biological parents. There were no significant group differences on behavioral performance on the task. In contrast, patterns of brain activation differed by group. The nonmaltreated children demonstrated stronger activation than the foster children across several regions including the right anterior cingulate cortex, middle frontal gyrus, and right lingual gyrus during correct no go trials, whereas the foster children displayed stronger activation than the nonmaltreated children in the left inferior parietal lobule and right superior occipital cortex including the lingual gyrus and cuneus during incorrect no go trials. These results provide preliminary evidence that the early adversity experienced by foster children impacts the neural substrates of inhibitory control. PMID:24229540

  5. Patterns of brain activation in foster children and nonmaltreated children during an inhibitory control task.

    PubMed

    Bruce, Jacqueline; Fisher, Philip A; Graham, Alice M; Moore, William E; Peake, Shannon J; Mannering, Anne M

    2013-11-01

    Children in foster care have often encountered a range of adverse experiences, including neglectful and/or abusive care and multiple caregiver transitions. Prior research findings suggest that such experiences negatively affect inhibitory control and the underlying neural circuitry. In the current study, event-related functional magnetic resonance imaging was employed during a go/no go task that assesses inhibitory control to compare the behavioral performance and brain activation of foster children and nonmaltreated children. The sample included two groups of 9- to 12-year-old children: 11 maltreated foster children and 11 nonmaltreated children living with their biological parents. There were no significant group differences on behavioral performance on the task. In contrast, patterns of brain activation differed by group. The nonmaltreated children demonstrated stronger activation than did the foster children across several regions, including the right anterior cingulate cortex, the middle frontal gyrus, and the right lingual gyrus, during correct no go trials, whereas the foster children displayed stronger activation than the nonmaltreated children in the left inferior parietal lobule and the right superior occipital cortex, including the lingual gyrus and cuneus, during incorrect no go trials. These results provide preliminary evidence that the early adversity experienced by foster children impacts the neural substrates of inhibitory control. PMID:24229540

  6. 48 CFR 352.270-8 - Prostitution and related activities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Prostitution and related... Prostitution and related activities. As prescribed in 370.701, the Contracting Officer shall insert the following clause: Prostitution and Related Activities (January 2010) (a) The U.S. Government is opposed...

  7. 48 CFR 352.270-8 - Prostitution and related activities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Prostitution and related... Prostitution and related activities. As prescribed in 370.701, the Contracting Officer shall insert the following clause: Prostitution and Related Activities (January 2010) (a) The U.S. Government is opposed...

  8. 48 CFR 352.270-8 - Prostitution and related activities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Prostitution and related... Prostitution and related activities. As prescribed in 370.701, the Contracting Officer shall insert the following clause: Prostitution and Related Activities (January 2010) (a) The U.S. Government is opposed...

  9. 48 CFR 352.270-8 - Prostitution and related activities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Prostitution and related... Prostitution and related activities. As prescribed in 370.701, the Contracting Officer shall insert the following clause: Prostitution and Related Activities (January 2010) (a) The U.S. Government is opposed...

  10. 48 CFR 352.270-8 - Prostitution and related activities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Prostitution and related... Prostitution and related activities. As prescribed in 370.701, the Contracting Officer shall insert the following clause: Prostitution and Related Activities (January 2010) (a) The U.S. Government is opposed...

  11. Bird activity levels related to weather

    USGS Publications Warehouse

    Robbins, C.S.

    1981-01-01

    The Breeding Bird Survey data bank serves as a primary source for studying effects of sky cover, wind speed, and temperature on bird census results. Other standardized methods, such as spot-mapping (Breeding Bird Census), point counts, banding, and the Winter Bird Survey, provide additional, but limited, means of assessing effects of weather. Numbers of songbirds detected are generally inversely correlated with wind speed, but hawks often are seen in larger numbers on windy days. Rain greatly reduces the numbers of birds detected. Cloud cover has relatively little influence on early morning bird counts during the peak of the breeding season. Fog selectively favors auditory detections of some species. Counts of many species are correlated with temperature, but effects are minor unless temperatures are extreme. Under marginal weather conditions, total species observed may be nearly normal, whereas number of individuals observed is reduced, as is the opportunity to record simultaneous registrations

  12. Active relearning for robust supervised training of emphysema patterns.

    PubMed

    Raghunath, Sushravya; Rajagopalan, Srinivasan; Karwoski, Ronald A; Bartholmai, Brian J; Robb, Richard A

    2014-08-01

    Radiologists are adept at recognizing the character and extent of lung parenchymal abnormalities in computed tomography (CT) scans. However, the inconsistent differential diagnosis due to subjective aggregation necessitates the exploration of automated classification based on supervised or unsupervised learning. The robustness of supervised learning depends on the training samples. Towards optimizing emphysema classification, we introduce a physician-in-the-loop feedback approach to minimize ambiguity in the selected training samples. An experienced thoracic radiologist selected 412 regions of interest (ROIs) across 15 datasets to represent 124, 129, 139 and 20 training samples of mild, moderate, severe emphysema and normal appearance, respectively. Using multi-view (multiple metrics to capture complementary features) inductive learning, an ensemble of seven un-optimized support vector models (SVM) each based on a specific metric was constructed in less than 6 s. The training samples were classified using seven SVM models and consensus labels were created using majority voting. In the active relearning phase, the ensemble-expert label conflicts were resolved by the expert. The efficacy and generality of active relearning feedback was assessed in the optimized parameter space of six general purpose classifiers across the seven dissimilarity metrics. The proposed just-in-time active relearning feedback with un-optimized SVMs yielded 15 % increase in classification accuracy and 25 % reduction in the number of support vectors. The average improvement in accuracy of six classifiers in their optimized parameter space was 21 %. The proposed cooperative feedback method enhances the quality of training samples used to construct automated classification of emphysematous CT scans. Such an approach could lead to substantial improvement in quantification of emphysema. PMID:24771303

  13. Altered patterns of cortical activation in ALS patients during attention and cognitive response inhibition tasks.

    PubMed

    Goldstein, L H; Newsom-Davis, I C; Bryant, V; Brammer, M; Leigh, P N; Simmons, A

    2011-12-01

    Since amyotrophic lateral sclerosis (ALS) can be accompanied by executive dysfunction, it is hypothesised that ALS patients will have impaired performance on tests of cognitive inhibition. We predicted that ALS patients would show patterns of abnormal activation in extramotor regions when performing tests requiring the inhibition of prepotent responses (the Stroop effect) and the inhibition of prior negatively primed responses (the negative priming effect) when compared to healthy controls. Functional magnetic resonance imaging was used to measure activation during a sparse sequence block design paradigm investigating the Stroop and negative priming effects in 14 ALS patients and 8 healthy age- and IQ-matched controls. Behavioural measures of performance were collected. Both groups' reaction times (RTs) reflected the Stroop effect during scanning. The ALS and control groups did not differ significantly for any of the behavioural measures but did show significant differences in cerebral activation during both tasks. The ALS group showed increased activation predominantly in the left middle temporal gyrus (BA 20/21), left superior temporal gyrus (BA 22) and left anterior cingulate gyrus (BA 32). Neither group's RT data showed clear evidence of a negative priming effect. However the ALS group showed decreased activation, relative to controls, particularly in the left cingulate gyrus (BA 23/24), left precentral gyrus (BA 4/6) and left medial frontal gyrus (BA 6). Greater cerebral activation in the ALS group accompanying the performance of the Stroop effect and areas of decreased activation during the negative priming comparison suggest altered inhibitory processing in ALS, consistent with other evidence of executive dysfunction in ALS. The current findings require further exploration in a larger study. PMID:21556876

  14. Relative Influences: Patterns of HPA Axis Concordance During Triadic Family Interaction

    PubMed Central

    Saxbe, Darby E.; Margolin, Gayla; Shapiro, Lauren Spies; Ramos, Michelle; Rodriguez, Aubrey; Iturralde, Esti

    2015-01-01

    Objective Within-family concordance in physiology may have implications for family system functioning and for individual health outcomes. Here, we examine patterns of association in cortisol within family triads. Methods A total of 103 adolescents and their parents sampled saliva at multiple timepoints before and after a conflict discussion task. We explored whether within-family associations existed and were moderated by stepparent presence and youth gender, and whether within-family patterns of influence correlated with individuals’ aggregate cortisol. Results Across the laboratory visit, the cortisol levels of fathers, mothers, and youth were positively associated. In time-lagged models, mothers’ cortisol predicted fathers’ cortisol levels sampled at the following timepoint, whereas fathers’ predicted youths’ and youths’ predicted mothers’ cortisol. These patterns appeared stronger in families not including stepparents. Youth gender moderated some associations: in the aggregate, youth were more strongly linked with their same-gender parent. In time-lagged models, girls were more closely linked to their mothers than boys, and both parents were more linked to girls. Youth showed higher aggregate cortisol output if they were more linked with their mothers, and lower output if more linked with their fathers; parents had higher output if they were more linked with their spouses and lower output if more linked with their children. Conclusions These results suggest that family members’ physiological activation may be linked during shared interaction, and that these patterns may be affected by family role and by youth gender. Our findings identify specific patterns of physiological influence within families that may inform family systems theories. PMID:23914815

  15. Geomechanical Simulations Related to UCG Activities

    SciTech Connect

    Vorobiev, O; Morris, J; Antoun, T; Friedmann, S J

    2008-07-11

    This paper presents results from a recent investigation into a range of geomechanical processes induced by UCG activities. The mechanical response of the coal and host rock mass plays a role in every stage of UCG operations. For example, cavity collapse during the burn has significant effect upon the rate of the burn itself. In the vicinity of the cavity, collapse and fracturing may result in enhanced hydraulic conductivity of the rock matrix above the burn chamber. Even far from the cavity, stresses due to subsidence may be sufficient to induce new fractures linking previously isolated aquifers. These mechanical processes are very important in understanding the risk of unacceptable subsidence and the potential for groundwater contamination. The mechanical processes are inherently non-linear, involving significant inelastic response, especially in the region closest to the cavity. in addition, the response of the rock mass involves both continuum and discrete mechanical behavior. To better understand these effects, they have applied a suite of highly non-linear computational tools in both two and three dimensions to a series of UCG scenarios. The calculations include combinations of continuum and discrete mechanical responses by employing fully coupled finite element and discrete element capabilities.

  16. Fractal Patterns of Neural Activity Exist within the Suprachiasmatic Nucleus and Require Extrinsic Network Interactions

    PubMed Central

    Hu, Kun; Meijer, Johanna H.; Shea, Steven A.; vanderLeest, Henk Tjebbe; Pittman-Polletta, Benjamin; Houben, Thijs; van Oosterhout, Floor; Deboer, Tom; Scheer, Frank A. J. L.

    2012-01-01

    The mammalian central circadian pacemaker (the suprachiasmatic nucleus, SCN) contains thousands of neurons that are coupled through a complex network of interactions. In addition to the established role of the SCN in generating rhythms of ∼24 hours in many physiological functions, the SCN was recently shown to be necessary for normal self-similar/fractal organization of motor activity and heart rate over a wide range of time scales—from minutes to 24 hours. To test whether the neural network within the SCN is sufficient to generate such fractal patterns, we studied multi-unit neural activity of in vivo and in vitro SCNs in rodents. In vivo SCN-neural activity exhibited fractal patterns that are virtually identical in mice and rats and are similar to those in motor activity at time scales from minutes up to 10 hours. In addition, these patterns remained unchanged when the main afferent signal to the SCN, namely light, was removed. However, the fractal patterns of SCN-neural activity are not autonomous within the SCN as these patterns completely broke down in the isolated in vitro SCN despite persistence of circadian rhythmicity. Thus, SCN-neural activity is fractal in the intact organism and these fractal patterns require network interactions between the SCN and extra-SCN nodes. Such a fractal control network could underlie the fractal regulation observed in many physiological functions that involve the SCN, including motor control and heart rate regulation. PMID:23185285

  17. Phasic and sustained fear in humans elicits distinct patterns of brain activity

    PubMed Central

    Alvarez, Ruben P.; Chen, Gang; Bodurka, Jerzy; Kaplan, Raphael; Grillon, Christian

    2011-01-01

    Aversive events are typically more debilitating when they occur unpredictably than predictably. Studies in humans and animals indicate that predictable and unpredictable aversive events can induce phasic and sustained fear, respectively. Research in rodents suggests that anatomically related but distinct neural circuits may mediate phasic and sustained fear. We explored this issue in humans by examining threat predictability in three virtual reality contexts, one in which electric shocks were predictably signaled by a cue, a second in which shocks occurred unpredictably but never paired with a cue, and a third in which no shocks were delivered. Evidence of threat-induced phasic and sustained fear was presented using fear ratings and skin conductance. Utilizing recent advances in functional magnetic resonance imaging (fMRI), we were able to conduct whole-brain fMRI at relatively high spatial resolution and still have enough sensitivity to detect transient and sustained signal changes in the basal forebrain. We found that both predictable and unpredictable threat evoked transient activity in the dorsal amygdala, but that only unpredictable threat produced sustained activity in a forebrain region corresponding to the bed nucleus of the stria terminalis complex. Consistent with animal models hypothesizing a role for the cortex in generating sustained fear, sustained signal increases to unpredictable threat were also found in anterior insula and a frontoparietal cortical network associated with hypervigilance. In addition, unpredictable threat led to transient activity in the ventral amygdala–hippocampal area and pregenual anterior cingulate cortex, as well as transient activation and subsequent deactivation of subgenual anterior cingulate cortex, limbic structures that have been implicated in the regulation of emotional behavior and stress responses. In line with basic findings in rodents, these results provide evidence that phasic and sustained fear in humans may

  18. Parallel-cascaded noniterative neural network for identfying closely related optical patterns

    NASA Astrophysics Data System (ADS)

    Hu, Chia-Lun J.

    2000-03-01

    When the training class patterns {Um} are closely related and they are inseparable (according to some targeted binary output vectors {Vm}) by a one- layered perceptron (OLP), then {Um} must be linearly dependent, and the output-augmented {Um} must be positively, linearly dependent. The learning of this OLP is then impossible no matter what learning rules we use, because the solution of the connection matrix just does not exist. However, we can always use a parallel-cascaded, two-layered perceptron (PCTLP) to realize this inseparable mapping. The design of this PCTLP is derived from the positive-linear independency condition we previously studied. It is a very intriguing mathematical derivation and the design of the PCTLP is much more efficient then that of the conventional series- cascaded, three-layered, neural networks. Also its robustness in recognizing any untrained, closely related patterns can be controlled and maximized. The physical origin, the theory, and the design of this novel, `universal' perceptron pattern recognition system will be discussed in detail in this paper.

  19. A novel pattern mining approach for identifying cognitive activity in EEG based functional brain networks.

    PubMed

    Thilaga, M; Vijayalakshmi, R; Nadarajan, R; Nandagopal, D

    2016-06-01

    The complex nature of neuronal interactions of the human brain has posed many challenges to the research community. To explore the underlying mechanisms of neuronal activity of cohesive brain regions during different cognitive activities, many innovative mathematical and computational models are required. This paper presents a novel Common Functional Pattern Mining approach to demonstrate the similar patterns of interactions due to common behavior of certain brain regions. The electrode sites of EEG-based functional brain network are modeled as a set of transactions and node-based complex network measures as itemsets. These itemsets are transformed into a graph data structure called Functional Pattern Graph. By mining this Functional Pattern Graph, the common functional patterns due to specific brain functioning can be identified. The empirical analyses show the efficiency of the proposed approach in identifying the extent to which the electrode sites (transactions) are similar during various cognitive load states. PMID:27401999

  20. Importance of the inherent and the relative surface energies in generating patterned layer in a solution process

    NASA Astrophysics Data System (ADS)

    Kim, Do-Kyung; Kwon, Hyeok Bin; Park, Hongsik; Choe, Eunji; Bae, Jin-Hyuk; Park, Jaehoon; Song, Seong-Ho

    2016-03-01

    We report the importance of the inherent and the relative surface energies in generating a patterned organic semiconductor layer through a solution process. The inherent and the relative surface energies of the substrate can be effectively controlled using polydimethylsiloxane in combination with an UV/ozone treatment. The controlled inherent surface energy in each region, as well as the high-order difference of relative surface energy, plays a significant role in generating the patterned layer. In addition, the patterned metal-semiconductor-metal (MSM) structure shows a lower lateral current than the non-patterned MSM structure because the current path is limited.

  1. Estimating repetitive spatiotemporal patterns from resting-state brain activity data.

    PubMed

    Takeda, Yusuke; Hiroe, Nobuo; Yamashita, Okito; Sato, Masa-Aki

    2016-06-01

    Repetitive spatiotemporal patterns in spontaneous brain activities have been widely examined in non-human studies. These studies have reported that such patterns reflect past experiences embedded in neural circuits. In human magnetoencephalography (MEG) and electroencephalography (EEG) studies, however, spatiotemporal patterns in resting-state brain activities have not been extensively examined. This is because estimating spatiotemporal patterns from resting-state MEG/EEG data is difficult due to their unknown onsets. Here, we propose a method to estimate repetitive spatiotemporal patterns from resting-state brain activity data, including MEG/EEG. Without the information of onsets, the proposed method can estimate several spatiotemporal patterns, even if they are overlapping. We verified the performance of the method by detailed simulation tests. Furthermore, we examined whether the proposed method could estimate the visual evoked magnetic fields (VEFs) without using stimulus onset information. The proposed method successfully detected the stimulus onsets and estimated the VEFs, implying the applicability of this method to real MEG data. The proposed method was applied to resting-state functional magnetic resonance imaging (fMRI) data and MEG data. The results revealed informative spatiotemporal patterns representing consecutive brain activities that dynamically change with time. Using this method, it is possible to reveal discrete events spontaneously occurring in our brains, such as memory retrieval. PMID:26979127

  2. Patterns of fire activity over Indonesia and Malaysia from polar and geostationary satellite observations

    NASA Astrophysics Data System (ADS)

    Hyer, Edward J.; Reid, Jeffrey S.; Prins, Elaine M.; Hoffman, Jay P.; Schmidt, Christopher C.; Miettinen, Jukka I.; Giglio, Louis

    2013-03-01

    Biomass burning patterns over the Maritime Continent of Southeast Asia are examined using a new active fire detection product based on application of the Wildfire Automated Biomass Burning Algorithm (WF_ABBA) to data from the imagers on the MTSAT geostationary satellites operated by the Japanese space agency JAXA. Data from MTSAT-1R and MTSAT-2 covering 34 months from September 2008 to July 2011 are examined for a study region consisting of Indonesia, Malaysia, and nearby environs. The spatial and temporal distributions of fires detected in the MTSAT WF_ABBA product are described and compared with active fire observations from MODIS MOD14 data. Land cover distributions for the two instruments are examined using a new 250 m land cover product from the National University of Singapore. The two products show broadly similar patterns of fire activity, land cover distribution of fires, and pixel fire radiative power (FRP). However, the MTSAT WF_ABBA data differ from MOD14 in important ways. Relative to MODIS, the MTSAT WF_ABBA product has lower overall detection efficiency, but more fires detected due to more frequent looks, a greater relative fraction of fires in forest and a lower relative fraction of fires in open areas, and significantly higher single-pixel retrieved FRP. The differences in land cover distribution and FRP between the MTSAT and MODIS products are shown to be qualitatively consistent with expectations based on pixel size and diurnal sampling. The MTSAT WF_ABBA data are used to calculate coverage-corrected diurnal cycles of fire for different regions within the study area. These diurnal cycles are preliminary but demonstrate that the fraction of diurnal fire activity sampled by the two MODIS sensors varies significantly by region and vegetation type. Based on the results from comparison of the two fire products, a series of steps is outlined to account for some of the systematic biases in each of these satellite products in order to produce a

  3. A central pattern generator producing alternative outputs: phase relations of leech heart motor neurons with respect to premotor synaptic input.

    PubMed

    Norris, Brian J; Weaver, Adam L; Wenning, Angela; García, Paul S; Calabrese, Ronald L

    2007-11-01

    The central pattern generator (CPG) for heartbeat in leeches consists of seven identified pairs of segmental heart interneurons and one unidentified pair. Four of the identified pairs and the unidentified pair of interneurons make inhibitory synaptic connections with segmental heart motor neurons. The CPG produces a side-to-side asymmetric pattern of intersegmental coordination among ipsilateral premotor interneurons corresponding to a similarly asymmetric fictive motor pattern in heart motor neurons, and asymmetric constriction pattern of the two tubular hearts: synchronous and peristaltic. Using extracellular techniques, we recorded, in 61 isolated nerve cords, the activity of motor neurons in conjunction with the phase reference premotor heart interneuron, HN(4), and another premotor interneuron that allowed us to assess the coordination mode. These data were then coupled with a previous description of the temporal pattern of premotor interneuron activity in the two coordination modes to synthesize a global phase diagram for the known elements of the CPG and the entire motor neuron ensemble. These average data reveal the stereotypical side-to-side asymmetric patterns of intersegmental coordination among the motor neurons and show how this pattern meshes with the activity pattern of premotor interneurons. Analysis of animal-to-animal variability in this coordination indicates that the intersegmental phase progression of motor neuron activity in the midbody in the peristaltic coordination mode is the most stereotypical feature of the fictive motor pattern. Bilateral recordings from motor neurons corroborate the main features of the asymmetric motor pattern. PMID:17728387

  4. Mesoscale damage patterns of Hurricane Frederic in relation to enhanced SMS imagery

    NASA Technical Reports Server (NTRS)

    Fujita, T. T.; Wakimoto, R. M.; Stiegler, D. J.

    1980-01-01

    An F-scale analysis of Hurricane Frederic (September 12 and 13, 1979) was performed in order to determine the structural damage patterns attributed to the storm. Enhanced SMS imagery revealed patterns of mesoscale features as well as features related to the shielding effects of trees and the grouping effect of structures. The scatter in estimating the damage scale was + or - 1 F-scale. It is shown that discrepancies in recorded wind speed and the estimated wind-speed from the F-scale are the result of different damage mechanisms of hurricane and tornado winds. Radar echoes revealed that the structure of Hurricane Frederic changed from an axisymmetric center to an instantaneous center of rotation. Finally, it is suggested that major hurricane wind and water damage be investigated in greater detail by aerial photography, damage vector mapping, and ground surveys.

  5. Inflammatory complications related to tattooing: a histopathological approach based on pattern analysis.

    PubMed

    Thum, Chee K; Biswas, Asok

    2015-01-01

    : Although tattooing is an ancient practice, its increasing popularity and social acceptance, variability of tattoo ink composition, sporadic reports of novel tattoo reactions and advances in the field of tattoo removal techniques make it a topic of immense interest among dermatologists and pathologists alike. Since effective legislation governing the tattoo industry is largely lacking in most regions of the world, it is important to recognize the range of tattoo-related complications from a dermatopathological perspective. Using a pattern-based approach, this review details the broad spectrum of inflammatory reactions, which may be encountered in adverse reactions associated with tattooing. Awareness of the range of inflammatory tattoo reactions is crucial as some of these patterns of inflammation can be associated with systemic disorders and others may serve as important clues for an underlying infective condition. PMID:23974222

  6. Patterns of work-related musculoskeletal disorders among workers in palm plantation occupation.

    PubMed

    Henry, Leonard Joseph; Jafarzadeh Esfehani, Ali; Ramli, Ayiesah; Ishak, Ismarulyusda; Justine, Maria; Mohan, Vikram

    2015-03-01

    This study investigated the patterns of ongoing work-related musculoskeletal disorders (WRMDs) and exposure risk to musculoskeletal injuries for various body regions among palm plantation workers. Standard Nordic Musculoskeletal Questionnaire (SNMQ) was used to assess the prevalence of musculoskeletal disorders symptoms. The Quick Exposure check (QEC) was used to assess the exposure risk of farmers to WRMDs. The common pattern of WRMDs was back pain (40%), followed by shoulder pain (19%). The QEC revealed high exposure risk for neck (56%), followed by back (45.6%). The results from the SNMQ showed that 58% reported pain in 1 region, followed by 2 regions (10.7%) and 3 regions (3.6%). Back pain and shoulder pain were found to be common among workers in palm plantation occupation. Nevertheless, the neck region appeared to have the highest risk of exposure to injuries. PMID:23417907

  7. Inhibition of inflammasome activation improves the impaired pattern of healing in genetically diabetic mice

    PubMed Central

    Bitto, Alessandra; Altavilla, Domenica; Pizzino, Gabriele; Irrera, Natasha; Pallio, Giovanni; Colonna, Michele R; Squadrito, Francesco

    2014-01-01

    Background and Purpose Type 2 diabetes impairs the healing process because of an exaggerated and persistent inflammatory response, and an altered expression pattern of angiogenic molecules. We investigated the effects of inflammasome blockade in diabetes-related wound-healings defects, in genetically diabetic mice. Experimental Approach An incisional skin wound model was produced on the back of female diabetic C57BL/KsJ-m +/+ Leptdb mice (db+/db+) and their normal littermates (db+/m+). Animals were treated daily with two inflammasome blocking agents, BAY 11-7082 (20 mg·kg−1 i.p.), or Brilliant Blue G (BBG, 45.5 mg·kg−1 i.p.), or vehicle. Mice were killed on 3, 6 and 12 days after skin injury to measure expression of the NOD-like receptor NLRP3, caspase-1, VEGF, the inflammasome adapter protein apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and the chemokine CXCL12. Wound levels of IL-1β and IL-18 were also measured, along with histological assessments of wound tissue and the time to complete wound closure. Key Results During healing, the diabetic mice exhibited increased activation of NLRP3, caspase-1, ASC, IL-1β and IL-18. They also showed a reduced expression of VEGF and CXCL12.Treatment with BAY 11-7082 or BBG, to block activation of the inflammasome, decreased the levels of pro-inflammatory molecules. Histological evaluation indicated that inflammasome blockade improved the impaired healing pattern, at day 12 in diabetic mice, along with a decreased time to complete skin healing. Conclusions and Implications These data strongly suggest that activation of the NLRP3 inflammasome is one of the key contributors to the delayed healing of wounds in diabetic mice. PMID:24329484

  8. Bacillus sphaericus asporogenous mutants: morphology, protein pattern and larvicidal activity.

    PubMed

    Charles, J F; Kalfon, A; Bourgouin, C; de Barjac, H

    1988-01-01

    Asporogenous mutants from Bacillus sphaericus strains 2297 and 1593-4, blocked at different stages of the sporulation process, were isolated. Two mutants (2297 Aspo30A and 2297 Aspo34) which were blocked early in sporulation did not possess any crystalline inclusions and were poorly toxic to Culex pipiens mosquito larvae. Other mutants (2297 Aspo115, 2297 Aspo24 and 1593-4 Aspo12) which were blocked at later stages synthesized crystal-like inclusions next to the forespores, and were highly toxic to mosquito larvae. Electrophoretic protein analysis of alkali extracts from mutants and wild type strains confirmed the absence of toxic crystal-related proteins in early-blocked mutants and their presence in later ones. Western blots with antisera directed against the crystal proteins confirmed those observations. PMID:3408593

  9. NASA's UAS [Unmanned Aircraft Systems] Related Activities

    NASA Technical Reports Server (NTRS)

    Bauer, Jeffrey

    2012-01-01

    NASA continues to operate all sizes of UAS in all classes of airspace both domestically and internationally. Missions range from highly complex operations in coordination with piloted aircraft, ground, and space systems in support of science objectives to single aircraft operations in support of aeronautics research. One such example is a scaled commercial transport aircraft being used to study recovery techniques due to large upsets. NASA's efforts to support routine UAS operations continued on several fronts last year. At the national level in the United States (U.S.), NASA continued its support of the UAS Executive Committee (ExCom) comprised of the Federal Aviation Administration (FAA), Department of Defense (DoD), Department of Homeland Security (DHS), and NASA. The committee was formed in recognition of the need of UAS operated by these agencies to access to the National Airspace System (NAS) to support operational, training, development and research requirements. Recommendations were received on how to operate both manned and unmanned aircraft in class D airspace and plans are being developed to validate and implement those recommendations. In addition the UAS ExCom has begun developing recommendations for how to achieve routine operations in remote areas as well as for small UAS operations in class G airspace. As well as supporting the UAS ExCom, NASA is a participant in the recently formed Aviation Rule Making Committee for UAS. This committee, established by the FAA, is intended to propose regulatory guidance which would enable routine civil UAS operations. As that effort matures NASA stands ready to supply the necessary technical expertise to help that committee achieve its objectives. By supporting both the UAS ExCom and UAS ARC, NASA is positioned to provide its technical expertise across the full spectrum of UAS airspace access related topic areas. The UAS NAS Access Project got underway this past year under the leadership of NASA s Aeronautics

  10. Pleiotropic patterning response to activation of Shh signaling in the limb Apical Ectodermal Ridge

    PubMed Central

    Wang, Chi-Kuang Leo; Tsugane, Mizuyo H.; Scranton, Victoria; Kosher, Robert A.; Pierro, Louis J.; Upholt, William B.; Dealy, Caroline N.

    2012-01-01

    Sonic hedgehog (Shh) signaling in the limb plays a central role in coordination of limb patterning and outgrowth. Shh expression in the limb is limited to the cells of the Zone of Polarizing Activity (ZPA), located in posterior limb bud mesoderm. Shh is not expressed by limb ectoderm or AER, but recent studies suggest a role for AER-Shh signaling in limb patterning. Here, we have examined the effects of activation of Shh signaling in the AER. We find that targeted expression of Shh in the AER activates constitutive Shh signaling throughout the AER and subjacent limb mesoderm, and causes a range of limb patterning defects with progressive severity from mild polydactyly, to polysyndactyly with proximal defects, to severe oligodactyly with phocomelia and partial limb ventralization. Our studies emphasize the importance of control of the timing, level and location of Shh pathway signaling for limb AP, PD and DV patterning. PMID:21465622

  11. Periodic patterning of the Drosophila eye is stabilized by the diffusible activator Scabrous

    PubMed Central

    Gavish, Avishai; Shwartz, Arkadi; Weizman, Abraham; Schejter, Eyal; Shilo, Ben-Zion; Barkai, Naama

    2016-01-01

    Generation of periodic patterns is fundamental to the differentiation of multiple tissues during development. How such patterns form robustly is still unclear. The Drosophila eye comprises ∼750 units, whose crystalline order is set during differentiation of the eye imaginal disc: an activation wave sweeping across the disc is coupled to lateral inhibition, sequentially selecting pro-neural cells. Using mathematical modelling, here we show that this template-based lateral inhibition is highly sensitive to spatial variations in biochemical parameters and cell sizes. We reveal the basis of this sensitivity, and suggest that it can be overcome by assuming a short-range diffusible activator. Clonal experiments identify Scabrous, a previously implicated inhibitor, as the predicted activator. Our results reveal the mechanism by which periodic patterning in the fly eye is stabilized against spatial variations, highlighting how the need to maintain robustness shapes the design of patterning circuits. PMID:26876750

  12. Chronic osteomyelitis: bone and gallium scan patterns associated with active disease

    SciTech Connect

    Tumeh, S.S.; Aliabadi, P.; Weissman, B.N.; McNeil, B.J.

    1986-03-01

    Bone and gallium scans are used to assess osteomyelitis patients with prior bone disease. To refine the criteria for interpreting these scans, the data from 136 consecutive patients with clinically suspected osteomyelitis were reviewed. Active osteomyelitis was diagnosed with surgery or biopsy and culture in 49 patients, excluded with the same criteria in 16, and excluded by clinical follow-up for at least 6 months in 71. Five different scintigraphic patterns were found. The true-positive and false-positive ratios, the likelihood ratios, and posterior probabilities for active osteomyelitis in each pattern were calculated. Only one pattern (gallium uptake exceeding bone-seeking radiopharmaceutical uptake) was indicative of active disease. Other patterns slightly raised or decreased the probability of disease. The extent of these changes varies directly with the prior probability of disease, determined from patient-specific factors (e.g., clinical data, laboratory data, findings on plain films) known best by the referring clinician.

  13. Peak-valley-peak pattern of histone modifications delineates active regulatory elements and their directionality.

    PubMed

    Pundhir, Sachin; Bagger, Frederik O; Lauridsen, Felicia B; Rapin, Nicolas; Porse, Bo T

    2016-05-19

    Formation of nucleosome free region (NFR) accompanied by specific histone modifications at flanking nucleosomes is an important prerequisite for enhancer and promoter activity. Due to this process, active regulatory elements often exhibit a distinct shape of histone signal in the form of a peak-valley-peak (PVP) pattern. However, different features of PVP patterns and their robustness in predicting active regulatory elements have never been systematically analyzed. Here, we present PARE, a novel computational method that systematically analyzes the H3K4me1 or H3K4me3 PVP patterns to predict NFRs. We show that NFRs predicted by H3K4me1 and me3 patterns are associated with active enhancers and promoters, respectively. Furthermore, asymmetry in the height of peaks flanking the central valley can predict the directionality of stable transcription at promoters. Using PARE on ChIP-seq histone modifications from four ENCODE cell lines and four hematopoietic differentiation stages, we identified several enhancers whose regulatory activity is stage specific and correlates positively with the expression of proximal genes in a particular stage. In conclusion, our results demonstrate that PVP patterns delineate both the histone modification landscape and the transcriptional activities governed by active enhancers and promoters, and therefore can be used for their prediction. PARE is freely available at http://servers.binf.ku.dk/pare. PMID:27095194

  14. Peak-valley-peak pattern of histone modifications delineates active regulatory elements and their directionality

    PubMed Central

    Pundhir, Sachin; Bagger, Frederik O.; Lauridsen, Felicia B.; Rapin, Nicolas; Porse, Bo T.

    2016-01-01

    Formation of nucleosome free region (NFR) accompanied by specific histone modifications at flanking nucleosomes is an important prerequisite for enhancer and promoter activity. Due to this process, active regulatory elements often exhibit a distinct shape of histone signal in the form of a peak-valley-peak (PVP) pattern. However, different features of PVP patterns and their robustness in predicting active regulatory elements have never been systematically analyzed. Here, we present PARE, a novel computational method that systematically analyzes the H3K4me1 or H3K4me3 PVP patterns to predict NFRs. We show that NFRs predicted by H3K4me1 and me3 patterns are associated with active enhancers and promoters, respectively. Furthermore, asymmetry in the height of peaks flanking the central valley can predict the directionality of stable transcription at promoters. Using PARE on ChIP-seq histone modifications from four ENCODE cell lines and four hematopoietic differentiation stages, we identified several enhancers whose regulatory activity is stage specific and correlates positively with the expression of proximal genes in a particular stage. In conclusion, our results demonstrate that PVP patterns delineate both the histone modification landscape and the transcriptional activities governed by active enhancers and promoters, and therefore can be used for their prediction. PARE is freely available at http://servers.binf.ku.dk/pare. PMID:27095194

  15. Activity Patterns of Preschool-Aged Children at Risk for Obesity

    PubMed Central

    Senso, Meghan M.; Trost, Stewart G.; Crain, A. Lauren; Seburg, Elisabeth M.; Anderson, Julie D.; Sherwood, Nancy E.

    2014-01-01

    Background Although the prevalence of obesity in young children highlights the importance of early interventions to promote physical activity (PA), there are limited data on activity patterns in this age group. The purpose of this study is to describe activity patterns in preschool-aged children and explore differences by weight status. Methods Analyses use baseline data from Healthy Homes/Healthy Kids- Preschool, a pilot obesity prevention trial of preschool-aged children overweight or at risk for overweight. A modified parent-reported version of the previous-day PA recall was used to summarize types of activity. Accelerometry was used to summarize daily and hourly activity patterns. Results “Playing with toys” accounted for the largest proportion of a child’s previous day, followed by “meals and snacks”, and “chores”. Accelerometry-measured daily time spent in sedentary behavior, light PA, and moderate-to-vigorous PA (MVPA) was 412, 247, and 69 minutes, respectively. Percent of hourly time spent in MVPA ranged from 3% to 13%, peaking in the late morning and evening hours. There were no statistically significant MVPA differences by weight status. Conclusions This study extends our understanding of activity types, amounts, and patterns in preschool-age children and warrants further exploration of differences in physical activity patterns by weight status. PMID:25133750

  16. Differences in activation patterns between eccentric and concentric quadriceps contractions.

    PubMed

    McHugh, Malachy P; Tyler, Timothy F; Greenberg, Scott C; Gleim, Gilbert W

    2002-02-01

    Previous studies analysing electromyograms (EMGs) from indwelling electrodes have indicated that fast-twitch motor units are selectively recruited for low-intensity eccentric contractions. The aim of this study was to compare the frequency content of surface EMGs from quadriceps muscles during eccentric and concentric contractions at various contraction intensities. Electromyograms were recorded from the rectus femoris, vastus lateralis and vastus medialis muscles of 10 men during isokinetic (1.05 rad x s(-1)) eccentric and concentric knee extension contractions at 25%, 50%, 75% and 100% of maximal voluntary contraction (MVC) for each contraction mode. Additionally, isometric contractions (70 degrees) were performed at each intensity. The mean frequency and root mean square (RMS) of the surface EMG were computed. Mean frequency was higher for eccentric than concentric contractions at 25% (P < 0.01), 50% (P < 0.01) and 75% (P < 0.05) but not at 100% MVC. It increased with increasing contraction intensity for isometric (P < 0.001) and concentric (P < 0.01) contractions but not for eccentric contractions (P = 0.27). The EMG amplitude (RMS) increased with increasing contraction intensity similarly in each contraction mode (P < 0.0001). Higher mean frequencies for eccentric than concentric contractions at submaximal contraction intensities is consistent with more fast-twitch motor units being active during eccentric contractions. PMID:11811575

  17. Resting cerebral glucose metabolism and perfusion patterns in women with posttraumatic stress disorder related to sexual assault.

    PubMed

    Kim, Shin-Young; Chung, Young-Ki; Kim, Bom Sahn; Lee, Su Jin; Yoon, Joon-Kee; An, Young-Sil

    2012-03-31

    In the literature, numerous trials using neuroimaging techniques have investigated brain function in patients with post-traumatic stress disorder (PTSD). However, the contrasting results showed that improvements, including in the study design, were required to reach consistent and convincing conclusions. This study evaluated the functional neuroimaging pattern of resting cerebral blood flow and glucose metabolism in patients with PTSD related to sexual assault. Twelve patients were enrolled for both brain single photon emission computed tomography (SPECT) and (18)F-fluorodeoxyglucose positron emission tomography (PET) investigations. All data were analyzed with statistical parametric mapping 2 (SPM2). The PTSD patients showed significant relative decreases in perfusion in the left hippocampus and in the basal ganglia compared with the control group. The PTSD group also had significantly lower cerebral glucosemetabolic activity in the left hippocampus and the superior temporal and precentral gyri than in the control group. These specific patterns of perfusion and glucose metabolism may be closely related to various neurophysiologic symptoms of PTSD. PMID:22464826

  18. Cloud — Aerosol interaction during lightning activity over land and ocean: Precipitation pattern assessment

    NASA Astrophysics Data System (ADS)

    Pal, Jayanti; Chaudhuri, Sutapa; Chowdhury, Arumita Roy; Bandyopadhyay, Tanuka

    2016-06-01

    The present study attempts to identify the land - ocean contrast in cloud - aerosol relation during lightning and non-lightning days and its effect on subsequent precipitation pattern. The thermal hypothesis in view of Convective Available Potential Energy (CAPE) behind the land - ocean contrast is observed to be insignificant in the present study region. The result shows that the lightning activities are significantly and positively correlated with aerosols over both land and ocean in case of low aerosol loading whereas for high aerosol loading the correlation is significant but, only over land. The study attempts to comprehend the mechanism through which the aerosol and lightning interact using the concept of aerosol indirect effect that includes the study of cloud effective radius, cloud fraction and precipitation rate. The result shows that the increase in lightning activity over ocean might have been caused due to the first aerosol indirect effect, while over land the aerosol indirect effect might have been suppressed due to lightning. Thus, depending on the region and relation between cloud parameters it is observed that the precipitation rate decreases (increases) over ocean during lightning (non-lightning) days. On the other hand during non-lightning days, the precipitation rate decreases over land.

  19. Top 10 research questions related to physical activity in preschool children.

    PubMed

    Pate, Russell R; O'Neill, Jennifer R; Brown, William H; McIver, Kerry L; Howie, Erin K; Dowda, Marsha

    2013-12-01

    The purpose of this article was to highlight important research needs related to physical activity in 3- to 5-year-old children. We identified research needs in 3 major categories: health effects, patterns of physical activity, and interventions and policies. The top research needs include identifying the health effects of physical activity, the effects of physical activity on the development of healthy weight, the effects of physical activity on learning and behavior, and the health implications of sedentary behavior. Research questions concerning patterns of physical activity include determining the prevalence of 3- to 5-year-olds meeting the current physical activity guidelines; the social and environmental factors that influence physical activity in home, preschool, and community settings; and how physical activity tracks into later childhood, adolescence, and adulthood. Research questions about interventions and policies include identifying the most effective strategies to promote physical activity in home, child care, and community settings and to reach diverse populations of young children, identifying effective intervention implementation and dissemination strategies, and determining the effectiveness of national, state, local, and institutional policies for increasing physical activity. In conclusion, research is needed to establish a full understanding of the health implications of physical activity in 3- to 5-year-old children, to better understand the nature of physical activity behavior in this group, and to learn how to promote physical activity in young children. PMID:24592775

  20. Muscle Activation Patterns When Passively Stretching Spastic Lower Limb Muscles of Children with Cerebral Palsy

    PubMed Central

    Bar-On, Lynn; Aertbeliën, Erwin; Molenaers, Guy; Desloovere, Kaat

    2014-01-01

    The definition of spasticity as a velocity-dependent activation of the tonic stretch reflex during a stretch to a passive muscle is the most widely accepted. However, other mechanisms are also thought to contribute to pathological muscle activity and, in patients post-stroke and spinal cord injury can result in different activation patterns. In the lower-limbs of children with spastic cerebral palsy (CP) these distinct activation patterns have not yet been thoroughly explored. The aim of the study was to apply an instrumented assessment to quantify different muscle activation patterns in four lower-limb muscles of children with CP. Fifty-four children with CP were included (males/females n = 35/19; 10.8±3.8 yrs; bilateral/unilateral involvement n =  32/22; Gross Motor Functional Classification Score I–IV) of whom ten were retested to evaluate intra-rater reliability. With the subject relaxed, single-joint, sagittal-plane movements of the hip, knee, and ankle were performed to stretch the lower-limb muscles at three increasing velocities. Muscle activity and joint motion were synchronously recorded using inertial sensors and electromyography (EMG) from the adductors, medial hamstrings, rectus femoris, and gastrocnemius. Muscles were visually categorised into activation patterns using average, normalized root mean square EMG (RMS-EMG) compared across increasing position zones and velocities. Based on the visual categorisation, quantitative parameters were defined using stretch-reflex thresholds and normalized RMS-EMG. These parameters were compared between muscles with different activation patterns. All patterns were dominated by high velocity-dependent muscle activation, but in more than half, low velocity-dependent activation was also observed. Muscle activation patterns were found to be both muscle- and subject-specific (p<0.01). The intra-rater reliability of all quantitative parameters was moderate to good. Comparing RMS-EMG between incremental

  1. Physical Activity Patterns and Psychological Correlates of Physical Activity among Singaporean Primary, Secondary, and Junior College Students

    ERIC Educational Resources Information Center

    Wang, C. K. John; Koh, K. T.; Biddle, Stuart J. H.; Liu, W. C.; Chye, Stefanie

    2011-01-01

    The purpose of this research was to examine physical activity patterns and psychological correlates of physical activity among primary, secondary, and junior college students in Singapore. A sample of 3,333 school students aged 10 to 18 years took part in the study. Results showed that the younger students had significantly higher physical…

  2. Activity pattern and energy expenditure due to physical activity before and during pregnancy in healthy Swedish women.

    PubMed

    Lof, Marie; Forsum, Elisabet

    2006-02-01

    Human pregnancy is associated with increased requirements for dietary energy and this increase may be partly offset by reductions in physical activity during gestation. Studies in well-nourished women have shown that the physical activity level (PAL), obtained as the total energy expenditure (TEE) divided by the BMR, decreases in late pregnancy. However, it is not known if this decrease is really caused by reductions in physical activity or if it is the result of decreases in energy expenditure/BMR (the so-called metabolic equivalent, MET) for many activities in late pregnancy. In the present study activity pattern, TEE and BMR were assessed in twenty-three healthy Swedish women before pregnancy as well as in gestational weeks 14 and 32. Activity pattern was assessed using a questionnaire and heart rate recording. TEE was assessed using the doubly labelled water method and BMR was measured by means of indirect calorimetry. When compared to the pre-pregnant value, there was little change in the PAL in gestational week 14 but it was significantly reduced in gestational week 32. Results obtained by means of the questionnaire and by heart rate recording showed that the activity pattern was largely unaffected by pregnancy. The findings support the following conclusion: in a population of well-nourished women where the activity pattern is maintained during pregnancy, the increase in BMR represents approximately the main part of the pregnancy-induced increase in TEE, at least until gestational week 32. PMID:16469145

  3. Speech Writing--A Major Public Relations Activity?

    ERIC Educational Resources Information Center

    Baskin, Otis

    The magnitude and importance of nonpolitical speech ghostwriting as a public relations activity was investigated. Corporate public relations departments and public relations counseling firms with more than five members that are listed in the directory of the Public Relations Society of America received a questionnaire asking seven questions about…

  4. Insights into the structural patterns of the antileishmanial activity of bi- and tricyclic N-heterocycles.

    PubMed

    Herrera, Lizzi; Stephens, David E; D'Avila, Abigail; George, Kathryn G; Arman, Hadi; Zhang, Yu; Perry, George; Lleonart, Ricardo; Larionov, Oleg V; Fernández, Patricia L

    2016-08-01

    The influence of various structural patterns in a series of novel bi- and tricyclic N-heterocycles on the activity against Leishmania major and Leishmania panamensis has been studied and compounds that are active in the low micromolar region have been identified. Both quinolines and tetrahydrooxazinoindoles (TOI) proved to have significant antileishmanial activities, while substituted indoles were inactive. We have also showed that a chloroquine analogue induces Leishmania killing by modulating macrophage activation. PMID:27376396

  5. Coherence of EMG activity and single motor unit discharge patterns in human rhythmical force production.

    PubMed

    Sosnoff, Jacob J; Vaillancourt, David E; Larsson, Lars; Newell, Karl M

    2005-03-30

    The purpose of this study was to examine the modulation of the motor neuronal pool as a function of task dynamics. Specifically, we investigated the effects of task frequency on the single motor unit discharge pattern, electromyogram (EMG) activity and effector force output. Myoelectric activity and effector force were recorded while young adults isometrically abducted their first dorsal interosseus at five sinusoidal targets (0.5 Hz, 1 Hz, 2 Hz, 3 Hz and 4 Hz) and at two force levels (5% and 25% maximum voluntary contraction (MVC)). Individual motor unit spike trains were isolated from the EMG. Auto-spectral and coherence analyses were performed on the force output, EMG and motor unit spike trains. The frequency of maximal coherence between the EMG and force output closely corresponded to the target frequency in all conditions. There was a broadband distribution of power with multiple peaks in the EMG and motor unit spectrums in the 0.5 Hz and 1 Hz targets. However, the EMG and motor unit spectrums in the 2 Hz, 3 Hz and 4 Hz targets were characterized by an increasingly narrower band of activity with one dominant peak that closely corresponded to the target. There is high coherence between EMG output and target force frequency, but the relative contribution of the fast and slow neuromuscular bands are differentially influenced by the task frequency. The rhythmical organization of neuromuscular output in the 0.5 Hz task is relatively broadband and similar to that shown previously for constant level force output. The frequency structure of neuromuscular organization becomes increasingly more narrowband as the frequency of the target increases (2-4 Hz). The modulation of the motor neuronal pool is adaptive and depends on the relative contribution of feedback and feedforward control processes, which are driven by the task demands. PMID:15698897

  6. The role of public relations activities in hospital choice.

    PubMed

    Tengilimoglu, Dilaver; Yesiltas, Mehmet; Kisa, Adnan; Dziegielewski, Sophia F

    2007-01-01

    Public relations activities for all organizations can have an important effect on consumer decision-making when buying goods or services. This study examines the effect that public relations activities can have regarding consumer decisions and choice. To explore exemplify this relationship a questionnaire was given to 971 patients within public, university and private hospitals in Ankara, Turkey. Study results show that public relations activities were a crucial factor in determining consumer hospital choice. The majority of respondents reported that the behaviors and attitude of personnel as public relations activities that support the hospital's reputation within the public were the primary variables in hospital choice. Health care managers can use these findings to further understand how patients make informed choices related to usage of a health care facility and to develop and/or improve public relations activities. PMID:19042526

  7. Quantitative Evaluation of Stomatal Cytoskeletal Patterns during the Activation of Immune Signaling in Arabidopsis thaliana

    PubMed Central

    Shimono, Masaki; Higaki, Takumi; Kaku, Hanae; Shibuya, Naoto; Hasezawa, Seiichiro

    2016-01-01

    Historically viewed as primarily functioning in the regulation of gas and water vapor exchange, it is now evident that stomata serve an important role in plant immunity. Indeed, in addition to classically defined functions related to cell architecture and movement, the actin cytoskeleton has emerged as a central component of the plant immune system, underpinning not only processes related to cell shape and movement, but also receptor activation and signaling. Using high resolution quantitative imaging techniques, the temporal and spatial changes in the actin microfilament array during diurnal cycling of stomatal guard cells has revealed a highly orchestrated transition from random arrays to ordered bundled filaments. While recent studies have demonstrated that plant stomata close in response to pathogen infection, an evaluation of stimulus-induced changes in actin cytoskeletal dynamics during immune activation in the guard cell, as well as the relationship of these changes to the function of the actin cytoskeleton and stomatal aperture, remains undefined. In the current study, we employed quantitative cell imaging and hierarchical clustering analyses to define the response of the guard cell actin cytoskeleton to pathogen infection and the elicitation of immune signaling. Using this approach, we demonstrate that stomatal-localized actin filaments respond rapidly, and specifically, to both bacterial phytopathogens and purified pathogen elicitors. Notably, we demonstrate that higher order temporal and spatial changes in the filament array show distinct patterns of organization during immune activation, and that changes in the naïve diurnal oscillations of guard cell actin filaments are perturbed by pathogens, and that these changes parallel pathogen-induced stomatal gating. The data presented herein demonstrate the application of a highly tractable and quantifiable method to assign transitions in actin filament organization to the activation of immune signaling in

  8. Generation, Language, Body Mass Index, and Activity Patterns in Hispanic Children

    PubMed Central

    Taverno, Sharon E.; Rollins, Brandi Y.; Francis, Lori A.

    2010-01-01

    Background The acculturation hypothesis proposes an overall disadvantage in health outcomes for Hispanic immigrants with more time spent living in the U.S., but little is known about how generational status and language may influence Hispanic children’s relative weight and activity patterns. Purpose The association between generation and language was investigated with relative weight (BMI z-scores), physical activity, screen time, and participation in extracurricular activities (e.g., sports, clubs) in a U.S.-based, nationally representative sample of Hispanic children. Methods Participants included 2,012 Hispanic children aged 6–11 years from the cross-sectional, 2003 National Survey of Children’s Health. Children were grouped according to generational status (1st, 2nd or 3rd), and the primary language spoken in the home (English vs non-English). Primary analyses included adjusted logistic and multinomial logistic regression to examine the relationships among variables; all analyses were conducted between 2008 and 2009. Results Compared to 3rd generation, English speakers, 1st and 2nd generation, non-English speakers were over two times more likely to be obese. Moreover, 1st generation, non-English speakers were half as likely to engage in regular physical activity and sports. Both 1st and 2nd generation, non-English speakers were less likely to participate in clubs compared to 2nd and 3rd generation, English speakers. Overall, all non–English speaking groups reported less screen time compared to 3rd generation, English speakers. Conclusions The hypothesis that Hispanics lose their health protection with more time spent in the U.S. was not supported in this sample of Hispanic children. PMID:20117570

  9. Age-related patterns of DHEAS among Turkana males of northern Kenya.

    PubMed

    Campbell, Benjamin C; Leslie, Paul; Campbell, Kenneth

    2007-12-01

    Dehydroepiandrosterone sulphate (DHEAS) has been widely associated with aging, but little is known about age-related decline of DHEAS in non-western populations. To determine the age-related pattern of DHEAS and its relationship to nutritional status in a subsistence population, we sampled Turkana nomads from northern Kenya. Subjects were 108 nomadic and 90 settled Turkana males, estimated ages 20 to 80+. Measures included blood DHEAS, height, weight, skinfolds, and waist circumference. Overall nomads exhibited less adiposity (5.7 +/- 1.8% versus 9.0 +/- 3.3% body fat) and higher blood DHEAS levels (5.2 +/- 3.3 microM versus 4.1 +/- 3.1 microM; p = 0.03). Age pattern of DHEAS was curvilinear, peaking in the 30s and 40s. General linear models (GLM) showed that blood DHEAS levels among men over 70 years of age were significantly lower than those in their 30s and 40s. Controlled for age, blood DHEAS was not related to adiposity. These results suggest that DHEAS levels were higher in those individuals who were calorie restricted. In addition, DHEAS levels rose more slowly than described in other populations, peaking in the fourth decade of life PMID:17853076

  10. Reactivation of Reward-Related Patterns from Single Past Episodes Supports Memory-Based Decision Making.

    PubMed

    Wimmer, G Elliott; Büchel, Christian

    2016-03-01

    Rewarding experiences exert a strong influence on later decision making. While decades of neuroscience research have shown how reinforcement gradually shapes preferences, decisions are often influenced by single past experiences. Surprisingly, relatively little is known about the influence of single learning episodes. Although recent work has proposed a role for episodes in decision making, it is largely unknown whether and how episodic experiences contribute to value-based decision making and how the values of single episodes are represented in the brain. In multiple behavioral experiments and an fMRI experiment, we tested whether and how rewarding episodes could support later decision making. Participants experienced episodes of high reward or low reward in conjunction with incidental, trial-unique neutral pictures. In a surprise test phase, we found that participants could indeed remember the associated level of reward, as evidenced by accurate source memory for value and preferences to re-engage with rewarded objects. Further, in a separate experiment, we found that high-reward objects shown as primes before a gambling task increased financial risk taking. Neurally, re-exposure to objects in the test phase led to significant reactivation of reward-related patterns. Importantly, individual variability in the strength of reactivation predicted value memory performance. Our results provide a novel demonstration that affect-related neural patterns are reactivated during later experience. Reactivation of value information represents a mechanism by which memory can guide decision making. PMID:26961943

  11. Dynamics of firing patterns, synchronization and resonances in neuronal electrical activities: experiments and analysis

    NASA Astrophysics Data System (ADS)

    Lu, Qishao; Gu, Huaguang; Yang, Zhuoqin; Shi, Xia; Duan, Lixia; Zheng, Yanhong

    2008-12-01

    Recent advances in the experimental and theoretical study of dynamics of neuronal electrical firing activities are reviewed. Firstly, some experimental phenomena of neuronal irregular firing patterns, especially chaotic and stochastic firing patterns, are presented, and practical nonlinear time analysis methods are introduced to distinguish deterministic and stochastic mechanism in time series. Secondly, the dynamics of electrical firing activities in a single neuron is concerned, namely, fast-slow dynamics analysis for classification and mechanism of various bursting patterns, one- or two-parameter bifurcation analysis for transitions of firing patterns, and stochastic dynamics of firing activities (stochastic and coherence resonances, integer multiple and other firing patterns induced by noise, etc.). Thirdly, different types of synchronization of coupled neurons with electrical and chemical synapses are discussed. As noise and time delay are inevitable in nervous systems, it is found that noise and time delay may induce or enhance synchronization and change firing patterns of coupled neurons. Noise-induced resonance and spatiotemporal patterns in coupled neuronal networks are also demonstrated. Finally, some prospects are presented for future research. In consequence, the idea and methods of nonlinear dynamics are of great significance in exploration of dynamic processes and physiological functions of nervous systems.

  12. Color patterns of closely related bird species are more divergent at intermediate levels of breeding-range sympatry.

    PubMed

    Martin, Paul R; Montgomerie, Robert; Lougheed, Stephen C

    2015-04-01

    Closely related species of birds often differ markedly in their color patterns. Here we examine the influence of breeding-range overlap (breeding sympatry) on the evolution of color pattern differences in a sample of closely related bird species. We used a sister-lineage method to analyze 73 phylogenetically independent comparisons among 246 species and 39 families of birds worldwide. We found that divergence of color patterns among closely related species was greater between sympatric than between allopatric lineages, but only at intermediate levels of sympatry (50%-80% breeding-range overlap). This pattern suggests that closely related species incur costs at intermediate levels of sympatry if they exhibit similar color patterns-costs that could include hybridization, interspecific aggression, competition for signaling space, or ecological interactions that secondarily influence color patterns. The decline in color pattern divergence with further increase in sympatry suggests either the relaxation of divergent selection, increased impediment of gene flow, or an increased role for counteracting selection at higher levels of sympatry. We also found that the differences in color pattern between sympatric and allopatric sister species were greatest at lower latitudes. The global scale and broad taxonomic coverage in our study suggest that the divergence of color patterns between sympatrically breeding closely related species is widespread in birds. PMID:25811081

  13. Patterns of gallium-67 scintigraphy in patients with acquired immunodeficiency syndrome and the AIDS related complex

    SciTech Connect

    Bitran, J.; Bekerman, C.; Weinstein, R.; Bennett, C.; Ryo, U.; Pinsky, S.

    1987-07-01

    Thirty-two patients with AIDS related complex (ARC) or acquired immunodeficiency syndrome (AIDS) underwent /sup 67/Ga scans as part of their evaluation. Three patterns of /sup 67/Ga biodistribution were found: lymph node uptake alone; diffuse pulmonary uptake; normal scan. Gallium-67 scans were useful in identifying clinically occult Pneumocystis carinii pneumonia in seven of 15 patients with ARC who were asymptomatic and had normal chest radiographs. Gallium scans are a useful ancillary procedure in the evaluation of patients with ARC or AIDS.

  14. Patterns of adolescents' beliefs about fighting and their relation to behavior and risk factors for aggression.

    PubMed

    Farrell, Albert D; Bettencourt, Amie; Mays, Sally; Kramer, Alison; Sullivan, Terri; Kliewer, Wendy

    2012-07-01

    This study examined adolescents' patterns of beliefs about aggression, and how these patterns relate to aggressive and prosocial behavior, and to risk factors associated with aggression. A sample of 477 sixth graders from two urban schools and a school in a nearby county completed measures of beliefs, behavior, and individual, peer and parental factors associated with aggression. Teacher ratings of participants' behavior and emotion regulation were also obtained. The urban sample was 84% African American; the county school was in a rural fringe area with a student population that was 45% Caucasian and 40% African American. Latent class analysis of items on a beliefs measure supported hypotheses predicting three groups: (a) a Beliefs Against Fighting (BAGF) group that opposed the use of aggression (31% of the sample); (b) a Fighting is Sometimes Necessary (FSNEC) group that endorsed beliefs that fighting is sometimes necessary or inevitable (41%), and (c) a Beliefs Supporting Fighting (BSUPF) group that supported aggression across multiple contexts (28%). Differences across groups were found on race/ethnicity and family structure, but not on gender. Significant differences were also found such that the FSNEC group fell between levels of the BAGF and BSUPF groups on most measures. In contrast, the FSNEC and BAGF groups both differed from the BSUPF group, but not from each other on measures of empathy, perceived effectiveness of nonviolence and aggression, and parental messages supporting nonviolence. These differences suggest the need for tailoring prevention approaches for subgroups of adolescents who differ in their patterns of beliefs. PMID:22307443

  15. Seasonal variation in American black bear Ursus americanus activity patterns: Quantification via remote photography

    USGS Publications Warehouse

    Bridges, A.S.; Vaughan, M.R.; Klenzendorf, S.

    2004-01-01

    Activity pattern plasticity may serve as an evolutionary adaptation to optimize fitness in an inconstant environment, however, quantifying patterns and demonstrating variation can be problematic. For American black bears Ursus americanus, wariness and habitat inaccessibility further complicate quantification. Radio telemetry has been the primary technique used to examine activity, however, interpretation error and limitation on numbers of animals available to monitor prevent extrapolation to unmarked or untransmittered members of the population. We used remote cameras to quantify black bear activity patterns and examined differences by season, sex and reproductive class in the Alleghany Mountains of western Virginia, USA. We used 1,533 pictures of black bears taken during 1998-2002 for our analyses. Black bears generally were diurnal in summer and nocturnal in autumn with a vespertine activity peak during both seasons. Bear-hound training seasons occurred during September and may offer explanation for the observed shift towards nocturnal behaviour. We found no substantial differences in activity patterns between sex and reproductive classes. Use of remote cameras allowed us to efficiently sample larger numbers of individual animals and likely offered a better approximation of population-level activity patterns than individual-level, telemetry-based methodologies.

  16. Assessing Activity Pattern Similarity with Multidimensional Sequence Alignment based on a Multiobjective Optimization Evolutionary Algorithm

    PubMed Central

    Kwan, Mei-Po; Xiao, Ningchuan; Ding, Guoxiang

    2015-01-01

    Due to the complexity and multidimensional characteristics of human activities, assessing the similarity of human activity patterns and classifying individuals with similar patterns remains highly challenging. This paper presents a new and unique methodology for evaluating the similarity among individual activity patterns. It conceptualizes multidimensional sequence alignment (MDSA) as a multiobjective optimization problem, and solves this problem with an evolutionary algorithm. The study utilizes sequence alignment to code multiple facets of human activities into multidimensional sequences, and to treat similarity assessment as a multiobjective optimization problem that aims to minimize the alignment cost for all dimensions simultaneously. A multiobjective optimization evolutionary algorithm (MOEA) is used to generate a diverse set of optimal or near-optimal alignment solutions. Evolutionary operators are specifically designed for this problem, and a local search method also is incorporated to improve the search ability of the algorithm. We demonstrate the effectiveness of our method by comparing it with a popular existing method called ClustalG using a set of 50 sequences. The results indicate that our method outperforms the existing method for most of our selected cases. The multiobjective evolutionary algorithm presented in this paper provides an effective approach for assessing activity pattern similarity, and a foundation for identifying distinctive groups of individuals with similar activity patterns. PMID:26190858

  17. Patterns of Intimate Partner Violence and Sexual Risk Behavior among Young Heterosexually Active Men.

    PubMed

    Casey, Erin A; Querna, Katherine; Masters, N Tatiana; Beadnell, Blair; Wells, Elizabeth A; Morrison, Diane M; Hoppe, Marilyn J

    2016-01-01

    Intimate partner violence (IPV) victimization is linked to sexual risk exposure among women. However, less is known about the intersection of IPV perpetration and sexual risk behavior among men. This study used data from a diverse, community sample of 334 heterosexually active young men, aged 18 to 25, across the United States to examine whether and how men with distinct IPV-related behavior patterns differed in sexual risk-related behavior and attitudes. Participants were recruited and surveyed online, and grouped conceptually based on the types of IPV perpetration behavior(s) used in a current or recent romantic relationship. Groups were then compared on relevant sexual risk variables. Men reporting both physical abuse and sexual coercion against intimate partners reported significantly higher numbers of lifetime partners, higher rates of nonmonogamy, greater endorsement of nonmonogamy, and less frequent condom use relative to nonabusive men or those reporting controlling behavior only. This group also had higher sexually transmitted infection (STI) exposure compared to men who used controlling behavior only and men who used sexual coercion only. Findings suggest that interventions with men who use physical and sexual violence need to account for not only the physical and psychological harm of this behavior but also the sexual risk to which men may expose their partners. PMID:26158212

  18. Patterns of Intimate Partner Violence and Sexual Risk Behavior among Young Heterosexually Active Men

    PubMed Central

    Casey, Erin A.; Querna, Katherine; Masters, N. Tatiana; Beadnell, Blair; Wells, Elizabeth A.; Morrison, Diane M.; Hoppe, Marilyn J.

    2015-01-01

    Intimate partner violence (IPV) victimization is linked to sexual risk exposure among women. However, less is known about the intersection of IPV perpetration and sexual risk behavior among men. This study used data from a diverse, community sample of 334 heterosexually active young men, aged 18 to 25, across the United States to examine whether and how men with distinct IPV-related behavior patterns differed in sexual risk–related behavior and attitudes. Participants were recruited and surveyed online, and grouped conceptually based on the types of IPV perpetration behavior(s) used in a current or recent romantic relationship. Groups were then compared on relevant sexual risk variables. Men reporting both physical abuse and sexual coercion against intimate partners reported significantly higher numbers of lifetime partners, higher rates of nonmonogamy, greater endorsement of nonmonogamy, and less frequent condom use relative to nonabusive men or those reporting controlling behavior only. This group also had higher sexually transmitted infection (STI) exposure compared to men who used controlling behavior only and men who used sexual coercion only. Findings suggest that interventions with men who use physical and sexual violence need to account for not only the physical and psychological harm of this behavior but also the sexual risk to which men may expose their partners. PMID:26158212

  19. Visual pattern discrimination by population retinal ganglion cells' activities during natural movie stimulation.

    PubMed

    Zhang, Ying-Ying; Wang, Ru-Bin; Pan, Xiao-Chuan; Gong, Hai-Qing; Liang, Pei-Ji

    2014-02-01

    In the visual system, neurons often fire in synchrony, and it is believed that synchronous activities of group neurons are more efficient than single cell response in transmitting neural signals to down-stream neurons. However, whether dynamic natural stimuli are encoded by dynamic spatiotemporal firing patterns of synchronous group neurons still needs to be investigated. In this paper we recorded the activities of population ganglion cells in bullfrog retina in response to time-varying natural images (natural scene movie) using multi-electrode arrays. In response to some different brief section pairs of the movie, synchronous groups of retinal ganglion cells (RGCs) fired with similar but different spike events. We attempted to discriminate the movie sections based on temporal firing patterns of single cells and spatiotemporal firing patterns of the synchronous groups of RGCs characterized by a measurement of subsequence distribution discrepancy. The discrimination performance was assessed by a classification method based on Support Vector Machines. Our results show that different movie sections of the natural movie elicited reliable dynamic spatiotemporal activity patterns of the synchronous RGCs, which are more efficient in discriminating different movie sections than the temporal patterns of the single cells' spike events. These results suggest that, during natural vision, the down-stream neurons may decode the visual information from the dynamic spatiotemporal patterns of the synchronous group of RGCs' activities. PMID:24465283

  20. Association of dietary patterns with sociodemographic and health-related factors among coronary artery disease (CAD) patients.

    PubMed

    Esmaili, Haleh; Mohd Yusof, Rokiah; Abu Saad, Hazizi; Ghaemian, Ali; Darani Zad, Nasrin

    2015-01-01

    This study aimed to identify the association of dietary patterns with sociodemographic and health-related characteristics among coronary artery disease patients. In this cross-sectional study, the participants were 250 patients coronary artery disease aged ≥ 40 years old. Data collection was done using questionnaires related to sociodemographics, health-related factors, and food-frequency intake information. Three dietary patterns (traditional, western, and healthy) were obtained using principal component analysis. The result showed that dietary patterns were associated with sociodemographic and health-related factors. According to the result, all the factors were taken very seriously when planning a promotional program for healthy lifestyle in prevention of CAD. PMID:25347717

  1. Patterns of impaired oral health-related quality of life dimensions.

    PubMed

    John, M T; Rener-Sitar, K; Baba, K; Čelebić, A; Larsson, P; Szabo, G; Norton, W E; Reissmann, D R

    2016-07-01

    How dental patients are affected by oral conditions can be described with the concept of oral health-related quality of life (OHRQoL). This concept intends to make the patient experience measurable. OHRQoL is multidimensional, and Oral Function, Oro-facial Pain, Oro-facial Appearance and Psychosocial Impact were suggested as its four dimensions and consequently four scores are needed for comprehensive OHRQoL assessment. When only the presence of dimensional impact is measured, a pattern of affected OHRQoL dimensions would describe in a simple way how oral conditions influence the individual. By determining which patterns of impact on OHRQoL dimensions exist in prosthodontic patients and general population subjects, we aimed to identify in which combinations oral conditions' functional, painful, aesthetical and psychosocial impact occurs. Data came from the Dimensions of OHRQoL Project with Oral Health Impact Profile (OHIP)-49 data from 6349 general population subjects and 2999 prosthodontic patients in the Learning Sample (N = 5173) and the Validation Sample (N = 5022). We hypothesised that all 16 patterns of OHRQoL dimensions should occur in these individuals who suffered mainly from tooth loss, its causes and consequences. A dimension was considered impaired when at least one item in the dimension was affected frequently. The 16 possible patterns of impaired OHRQoL dimensions were found in patients and general population subjects in both Learning and Validation Samples. In a four-dimensional OHRQoL model consisting Oral Function, Oro-facial Pain, Oro-facial Appearance and Psychosocial Impact, oral conditions' impact can occur in any combination of the OHRQoL dimensions. PMID:27027734

  2. Role of Individual and School Factors in Physical Activity Patterns of Secondary-Level Spanish Students

    ERIC Educational Resources Information Center

    Juan, Francisco Ruiz; Bengoechea, Enrique Garcia; Montes, Maria Elena Garcia; Bush, Paula Louise

    2010-01-01

    Background: While the importance of individual and school factors as correlates of overall youth physical activity has been demonstrated by previous research, less is known about the relationship of these factors with specific patterns of physical activity during adolescence. Thus, the purpose of this study was to examine the association of…

  3. Friendship Characteristics and Activity Patterns of Adolescents with an Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Kuo, Melissa H.; Orsmond, Gael I.; Cohn, Ellen S.; Coster, Wendy J.

    2013-01-01

    This study compared perceptions of adolescents' friendships between adolescents with an autism spectrum disorder (ASD) and their parents, examined factors associated with friendship qualities, and investigated the adolescents' reports on the activities they did with friends and how activity patterns differed by gender. Ninety-one…

  4. Motives for Using Facebook, Patterns of Facebook Activities, and Late Adolescents' Social Adjustment to College

    ERIC Educational Resources Information Center

    Yang, Chia-chen; Brown, B. Bradford

    2013-01-01

    Previous studies have confirmed that Facebook, the leading social networking site among young people, facilitates social connections among college students, but the specific activities and motives that foster social adjustment remain unclear. This study examined associations between patterns of Facebook activity, motives for using Facebook, and…

  5. Twenty-four hour activity budgets and patterns of behavior in captive ocelots (Leopardus pardalis).

    PubMed

    Weller, S H.; Bennett, C L.

    2001-02-16

    Activity budgets of captive ocelots (Leopardus pardalis) were assessed from over 547h of observational data obtained from six ocelots; two females at the Dallas Zoo (Dallas, TX), two females at the Caldwell Zoo (Tyler, TX) and a male and female at the Fossil Rim Wildlife Center (Glen Rose, TX). Data were examined for the percentage of active behaviors exhibited during the day and nighttime hours; temporal patterns of active, pace, exploratory and marking behavior, and for significance in pacing behavior between pre- and post-feeding times. The captive cats had a bimodal pattern of active behavior similar to field studies of wild ocelots, except that the timing of the active peaks were closer to the diurnal hours for the captive cats. The captive ocelots were less active than wild ocelots, and more diurnal. Also, the captive cats exhibited stereotypic pacing. When the percentage of time of active behavior was assessed for each cat, a strong variation between individuals and institution was not seen. Pacing behavior was highest prior to the feeding times for the cats. In assessing patterns of behavior, peaks in marking and exploratory behavior in the cats did not occur at the same time as the peaks in active behavior. However, we did see institutional differences in the pattern of exploratory and marking behavior, which may have been influenced by differing management practices. PMID:11179560

  6. TI: Geohazards in Related to Neotectonic Patterns of Taiwan Based on Recent Multi-Source Data

    NASA Astrophysics Data System (ADS)

    Lu, C.; Chan, Y.; Kuo, L.; Chang, K.; Lee, J.; Chen, C.

    2010-12-01

    : We employ multi-source approach to study the neotectonic patterns of Taiwan by means of a Geographical Information System (GIS) which enables us to better compare various data sources and their possible implications for geohazards. The neotectonics of plate convergence around Taiwan can be well demonstrated by the metamorphic foliation map, the GPS horizontal velocity field, the GPS vertical velocity field, the shear strain rate, the rotation rate and the dilatation rate maps. Various types of information are effectively taken into account in this study, such as 3D topography and bathymetry, geological maps, recent results of geodesy and geophysics, and field geologic observations. Based on the compiled information we proposed the major structures of Taiwan can be divided into four domains with dominant deformation patterns: the northern Taiwan extensional and transcurrent zone, the Foothills and Hsuehshan compressional zone, the Backbone Range exhumation and extensional zone, and the Coastal Range compressional zone. The active thrusts are concentrated within the compressional zones while the active normal faults are concentrated within the extensional zone, particularly the Backbone Range, the metamorphic core of Taiwan. Furthermore, the strike-slip faults are distributed penetratively through the Taiwan Island indicating adjustment of stress through such fault mechanism is common in all different types of deformational regime.

  7. Animal Related Activities as Determinants of Species Knowledge

    ERIC Educational Resources Information Center

    Randler, Christoph

    2010-01-01

    Previous work has established a relationship between knowledge and environmental concern. Different factors may contribute to this knowledge and animal-related leisure activities may also contribute to this knowledge. 390 participants in Leipzig, Germany were interviewed to assess their animal-related leisure activities, their demographic status…

  8. 12 CFR 225.123 - Activities closely related to banking.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Activities closely related to banking. 225.123 Section 225.123 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL... Holding Companies Interpretations § 225.123 Activities closely related to banking. (a) Effective June...

  9. 12 CFR 225.131 - Activities closely related to banking.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Activities closely related to banking. 225.131 Section 225.131 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL... Holding Companies Interpretations § 225.131 Activities closely related to banking. (a) Bank...

  10. MALDI-MS Patterning of Caspase Activities and Its Application in the Assessment of Drug Resistance.

    PubMed

    Hu, Junjie; Liu, Fei; Ju, Huangxian

    2016-06-01

    Mass spectrometry (MS) has been widely used for enzyme activity assays. Herein, we propose a MALDI-MS patterning strategy for the convenient visual presentation of multiple enzyme activities with an easy-to-prepare chip. The array-based caspase-activity patterned chip (Casp-PC) is fabricated by hydrophobically assembling different phospholipid-tagged peptide substrates on a modified ITO slide. The advantages of amphipathic phospholipids lead to high-quality mass spectra for imaging analysis. Upon the respective cleavage of these substrates by different caspases, such as caspase-1, -2, -3, and -8, to produce a mass shift, the enzyme activities can be directly evaluated by MALDI-MS patterning by m/z-dependent imaging of the cleavage products. The ability to identify drug-sensitive/resistant cancer cells and assess the curative effects of anticancer drugs is demonstrated, indicating the applicability of the method and the designed chip. PMID:27101158

  11. Bedtime activities, sleep environment, and sleep/wake patterns of Japanese elementary school children.

    PubMed

    Oka, Yasunori; Suzuki, Shuhei; Inoue, Yuich

    2008-01-01

    Bedtime activities, sleep environment, and their impact on sleep/wake patterns were assessed in 509 elementary school children (6-12 years of age; 252 males and 257 females). Television viewing, playing video games, and surfing the Internet had negative impact on sleep/wake parameters. Moreover, presence of a television set or video game in the child's bedroom increased their activity before bedtime. Time to return home later than 8 p.m. from after-school activity also had a negative impact on sleep/wake patterns. Health care practitioners should be aware of the potential negative impact of television, video games, and the Internet before bedtime, and also the possibility that late after-school activity can disturb sleep/wake patterns. PMID:18853306

  12. Activity patterns in elementary and high school students exposed to oxidant pollution

    SciTech Connect

    Spier, C.E.; Little, D.E.; Trim, S.C.; Johnson, T.R.; Linn, W.S.; Hackney, J.D. )

    1992-07-01

    We investigated activity patterns of 17 elementary school students aged 10-12, and 19 high school students aged 13-17, in suburban Los Angeles during the oxidant pollution season. Individuals' relationships between ventilation rate (VR) and heart rate (HR) were calibrated' in supervised outdoor walking/jogging. Log VR was consistently proportional to HR; although calibrations' were limited by a restricted range of exercise, and possibly by artifact due to mouthpiece breathing, which may cause overestimation of VR at rest. Each subject then recorded activities in diaries, and recorded HR once per minute by wearing Heart Watches, over 3 days (Saturday-Monday). For each activity the subject estimated a breathing rate--slow (slow walking), medium (fast walking), or fast (running). VR ranges for each breathing rate and activity type were estimated from HR recordings. High-school students' diaries showed their aggregate distribution of waking hours as 68% slow inside, 8% slow outside, 10% medium inside, 9% medium outside, 1.5% fast inside, 1.5% fast outside. Elementary students' distribution was 47% slow inside, 15% slow outside, 20% medium inside, 12% medium outside, 2.5% fast inside, 3.5% fast outside. Sleep occupied 38% of high-school students' and 40% of elementary students' time; HR were generally lower in sleep than in slow waking activity. High school students' mean VR estimates were 13 L/min for slow breathing, 18 for medium, and 23 for fast; elementary students' were 14 slow, 18 medium, and 19 fast. VR distributions were approximately lognormal. Maximum estimated VR were approximately 70 L/min in elementary and approximately 100 L/min in high school students. Compared to adults studied similarly, students reported more medium or fast breathing, and had equal or higher VR estimates during slow and medium breathing despite their smaller size. These results suggest that, relative to body size, young people inhale larger doses of outdoor air pollutants than adults.

  13. Species-specific differences in relative eye size are related to patterns of edge avoidance in an Amazonian rainforest bird community

    PubMed Central

    Martínez-Ortega, Cristina; Santos, Eduardo SA; Gil, Diego

    2014-01-01

    Eye size shows a large degree of variation among species, even after correcting for body size. In birds, relatively larger eyes have been linked to predation risk, capture of mobile prey, and nocturnal habits. Relatively larger eyes enhance visual acuity and also allow birds to forage and communicate in low-light situations. Complex habitats such as tropical rain forests provide a mosaic of diverse lighting conditions, including differences among forest strata and at different distances from the forest edge. We examined in an Amazonian forest bird community whether microhabitat occupancy (defined by edge avoidance and forest stratum) was a predictor of relative eye size. We found that relative eye size increased with edge avoidance, but did not differ according to forest stratum. Nevertheless, the relationship between edge avoidance and relative eye size showed a nonsignificant positive trend for species that inhabit lower forest strata. Our analysis shows that birds that avoid forest edges have larger eyes than those living in lighter parts. We expect that this adaptation may allow birds to increase their active daily period in dim areas of the forest. The pattern that we found raises the question of what factors may limit the evolution of large eyes. PMID:25614788

  14. Relation Between Higher Physical Activity and Public Transit Use

    PubMed Central

    Vernez Moudon, Anne; Kang, Bumjoon; Hurvitz, Philip M.; Zhou, Chuan

    2014-01-01

    Objectives. We isolated physical activity attributable to transit use to examine issues of substitution between types of physical activity and potential confounding of transit-related walking with other walking. Methods. Physical activity and transit use data were collected in 2008 to 2009 from 693 Travel Assessment and Community study participants from King County, Washington, equipped with an accelerometer, a portable Global Positioning System, and a 7-day travel log. Physical activity was classified into transit- and non–transit-related walking and nonwalking time. Analyses compared physical activity by type between transit users and nonusers, between less and more frequent transit users, and between transit and nontransit days for transit users. Results. Transit users had more daily overall physical activity and more total walking than did nontransit users but did not differ on either non–transit-related walking or nonwalking physical activity. Most frequent transit users had more walking time than least frequent transit users. Higher physical activity levels for transit users were observed only on transit days, with 14.6 minutes (12.4 minutes when adjusted for demographics) of daily physical activity directly linked with transit use. Conclusions. Because transit use was directly related to higher physical activity, future research should examine whether substantive increases in transit access and use lead to more physical activity and related health improvements. PMID:24625142

  15. STUDIES OF RELATIONSHIPS BETWEEN MOLECULAR STRUCTURE AND BIOLOGICAL ACTIVITY BY PATTERN RECOGNITION METHODS

    EPA Science Inventory

    The attempt to rationalize the connections between the molecular structures of organic compounds and their biological activities comprises the field of structure-activity relations (SAR) studies. Correlations between structure and activity are important for the understanding and ...

  16. Development of Active Regions: Flows, Magnetic-Field Patterns and Bordering Effect

    NASA Astrophysics Data System (ADS)

    Getling, A. V.; Ishikawa, R.; Buchnev, A. A.

    2016-02-01

    A qualitative analysis is given of the data on the full magnetic and velocity vector fields in a growing sunspot group, recorded nearly simultaneously with the Solar Optical Telescope on the Hinode satellite. Observations of a young bipolar subregion developing within AR 11313 were carried out on 9 - 10 October 2011. Our aim was to form an idea about the consistency of the observed pattern with the well-known rising-tube model of the formation of bipolar active regions and sunspot groups. We find from our magnetograms that the distributions of the vertical [Bv] and the horizontal [Bh] component of the magnetic field over the area of the magnetic subregion are spatially well correlated; in contrast, the rise of a flux-tube loop would result in a qualitatively different pattern, with the maxima of the two magnetic-field components spatially separated: the vertical field would be the strongest where either spot emerges, while the maximum horizontal-field strengths would be reached in between them. A specific feature, which we call the bordering effect, is revealed: some local extrema of Bv are bordered with areas of locally enhanced Bh. This effect suggests a fountainlike spatial structure of the magnetic field near the Bv extrema, which is also hardly compatible with the emergence of a flux-tube loop. The vertical-velocity field in the area of the developing active subregion does not exhibit any upflow on the scale of the whole subregion, which should be related to the rising-tube process. Thus, our observational data can hardly be interpreted in the framework of the rising-tube model.

  17. Physical activity patterns among South-Asian adults: a systematic review

    PubMed Central

    2013-01-01

    Physical activity (PA) has many beneficial physical and mental health effects. Physical inactivity is considered the fourth leading risk factor for global mortality. At present there are no systematic reviews on PA patterns among South Asian adults residing in the region. The present study aims to systematically evaluate studies on PA patterns in South Asian countries. A five-staged comprehensive search of the literature was conducted in Medline, Web of Science and SciVerse Scopus using keywords ‘Exercise’, ‘Walking’, ‘Physical activity’, ‘Inactivity’, ‘Physical Activity Questionnaire’, ‘International Physical Activity Questionnaire’, ‘IPAQ’, ‘Global Physical Activity Questionnaire’ and ‘GPAQ’, combined with individual country names. The search was restricted to English language articles conducted in humans and published before 31st December 2012. To obtain additional data a manual search of the reference lists of articles was performed. Data were also retrieved from the search of relevant web sites and online resources. The total number of hits obtained from the initial search was 1,771. The total number of research articles included in the present review is eleven (India-8, Sri Lanka-2, Pakistan-1). In addition, eleven country reports (Nepal-3, Bangladesh-2, India-2, Sri Lanka-2, Bhutan-1, Maldives-1) of World Health Organization STEPS survey from the South-Asian countries were retrieved online. In the research articles the overall prevalence of inactivity was as follows; India (18.5%-88.4%), Pakistan (60.1%) and Sri Lanka (11.0%-31.8%). STEPS survey reports were available from all countries except Pakistan. Overall in majority of STEPS surveys females were more inactive compared to males. Furthermore, leisure related inactivity was >75% in studies reporting inactivity in this domain and people were more active in transport domain when compared with the other domains. In conclusion, our results show that there is a wide

  18. Development of coherent neuronal activity patterns in mammalian cortical networks: common principles and local hetereogeneity.

    PubMed

    Egorov, Alexei V; Draguhn, Andreas

    2013-01-01

    Many mammals are born in a very immature state and develop their rich repertoire of behavioral and cognitive functions postnatally. This development goes in parallel with changes in the anatomical and functional organization of cortical structures which are involved in most complex activities. The emerging spatiotemporal activity patterns in multi-neuronal cortical networks may indeed form a direct neuronal correlate of systemic functions like perception, sensorimotor integration, decision making or memory formation. During recent years, several studies--mostly in rodents--have shed light on the ontogenesis of such highly organized patterns of network activity. While each local network has its own peculiar properties, some general rules can be derived. We therefore review and compare data from the developing hippocampus, neocortex and--as an intermediate region--entorhinal cortex. All cortices seem to follow a characteristic sequence starting with uncorrelated activity in uncoupled single neurons where transient activity seems to have mostly trophic effects. In rodents, before and shortly after birth, cortical networks develop weakly coordinated multineuronal discharges which have been termed synchronous plateau assemblies (SPAs). While these patterns rely mostly on electrical coupling by gap junctions, the subsequent increase in number and maturation of chemical synapses leads to the generation of large-scale coherent discharges. These patterns have been termed giant depolarizing potentials (GDPs) for predominantly GABA-induced events or early network oscillations (ENOs) for mostly glutamatergic bursts, respectively. During the third to fourth postnatal week, cortical areas reach their final activity patterns with distinct network oscillations and highly specific neuronal discharge sequences which support adult behavior. While some of the mechanisms underlying maturation of network activity have been elucidated much work remains to be done in order to fully

  19. Extraction and Characterization of Essential Discharge Patterns from Multisite Recordings of Spiking Ongoing Activity

    PubMed Central

    Storchi, Riccardo; Biella, Gabriele E. M.; Liberati, Diego; Baselli, Giuseppe

    2009-01-01

    Background Neural activation patterns proceed often by schemes or motifs distributed across the involved cortical networks. As neurons are correlated, the estimate of all possible dependencies quickly goes out of control. The complex nesting of different oscillation frequencies and their high non-stationariety further hamper any quantitative evaluation of spiking network activities. The problem is exacerbated by the intrinsic variability of neural patterns. Methodology/Principal Findings Our technique introduces two important novelties and enables to insulate essential patterns on larger sets of spiking neurons and brain activity regimes. First, the sampling procedure over N units is based on a fixed spike number k in order to detect N-dimensional arrays (k-sequences), whose sum over all dimension is k. Then k-sequences variability is greatly reduced by a hierarchical separative clustering, that assigns large amounts of distinct k-sequences to few classes. Iterative separations are stopped when the dimension of each cluster comes to be smaller than a certain threshold. As threshold tuning critically impacts on the number of classes extracted, we developed an effective cost criterion to select the shortest possible description of our dataset. Finally we described three indexes (C,S,R) to evaluate the average pattern complexity, the structure of essential classes and their stability in time. Conclusions/Significance We validated this algorithm with four kinds of surrogated activity, ranging from random to very regular patterned. Then we characterized a selection of ongoing activity recordings. By the S index we identified unstable, moderatly and strongly stable patterns while by the C and the R indices we evidenced their non-random structure. Our algorithm seems able to extract interesting and non-trivial spatial dynamics from multisource neuronal recordings of ongoing and potentially stimulated activity. Combined with time-frequency analysis of LFPs could provide a

  20. Hippocampal CA2 activity patterns change over time to a larger extent than between spatial contexts.

    PubMed

    Mankin, Emily A; Diehl, Geoffrey W; Sparks, Fraser T; Leutgeb, Stefan; Leutgeb, Jill K

    2015-01-01

    The hippocampal CA2 subregion has a different anatomical connectivity pattern within the entorhino-hippocampal circuit than either the CA1 or CA3 subregion. Yet major differences in the neuronal activity patterns of CA2 compared with the other CA subregions have not been reported. We show that standard spatial and temporal firing patterns of individual hippocampal principal neurons in behaving rats, such as place fields, theta modulation, and phase precession, are also present in CA2, but that the CA2 subregion differs substantially from the other CA subregions in its population coding. CA2 ensembles do not show a persistent code for space or for differences in context. Rather, CA2 activity patterns become progressively dissimilar over time periods of hours to days. The weak coding for a particular context is consistent with recent behavioral evidence that CA2 circuits preferentially support social, emotional, and temporal rather than spatial aspects of memory. PMID:25569350

  1. Patterns of Tree Species Diversity in Relation to Climatic Factors on the Sierra Madre Occidental, Mexico

    PubMed Central

    Silva-Flores, Ramón; Pérez-Verdín, Gustavo; Wehenkel, Christian

    2014-01-01

    Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole), 54 species of Quercus (ca. 9–14%), 7 species of Arbutus (ca. 50%) and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally higher in cold

  2. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

    PubMed

    Silva-Flores, Ramón; Pérez-Verdín, Gustavo; Wehenkel, Christian

    2014-01-01

    Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole), 54 species of Quercus (ca. 9-14%), 7 species of Arbutus (ca. 50%) and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally higher in cold

  3. Mirrored patterns of lateralized neuronal activation reflect old and new memories in the avian auditory cortex.

    PubMed

    Olson, Elizabeth M; Maeda, Rie K; Gobes, Sharon M H

    2016-08-25

    In monolingual humans, language-related brain activation shows a distinct lateralized pattern, in which the left hemisphere is often dominant. Studies are not as conclusive regarding the localization of the underlying neural substrate for language in sequential language learners. Lateralization of the neural substrate for first and second language depends on a number of factors including proficiency and early experience with each language. Similar to humans learning speech, songbirds learn their vocalizations from a conspecific tutor early in development. Here, we show mirrored patterns of lateralization in the avian analog of the mammalian auditory cortex (the caudomedial nidopallium [NCM]) in sequentially tutored zebra finches (Taeniopygia guttata​) in response to their first tutor song, learned early in development, and their second tutor song, learned later in development. The greater the retention of song from their first tutor, the more right-dominant the birds were when exposed to that song; the more birds learned from their second tutor, the more left-dominant they were when exposed to that song. Thus, the avian auditory cortex may preserve lateralized neuronal traces of old and new tutor song memories, which are dependent on proficiency of song learning. There is striking resemblance in humans: early-formed language representations are maintained in the brain even if exposure to that language is discontinued. The switching of hemispheric dominance related to the acquisition of early auditory memories and subsequent encoding of more recent memories may be an evolutionary adaptation in vocal learners necessary for the behavioral flexibility to acquire novel vocalizations, such as a second language. PMID:27288718

  4. Cooperative Learning Activities Related to Women Chemists and Physicists.

    ERIC Educational Resources Information Center

    Reat, Kay

    This collection of activities related to women chemists and physicists is designed for use in cooperative groups of three students each. Each of eight activities consists of a written account of the career and life of an historical woman scientist and four writing activity suggestions. The writings from each group can then be organized into one…

  5. Could Watching TV Be Good for You? Examining How Media Consumption Patterns Relate to Salivary Cortisol.

    PubMed

    Nabi, Robin L; Prestin, Abby; So, Jiyeon

    2016-11-01

    This research explores whether media diet influences health, not through its effects on cognition and behavior but rather through its effects on biomarkers of stress, which are implicated in a host of acute and chronic illnesses. Two hundred and forty young adults completed assessments of their media consumption habits followed at least 2 days later by measures of the stress-related hormone cortisol. Results suggest that frequency of consuming different media and genres may decrease cortisol under certain conditions and increase them under others. Further, the patterns of results were wholly different from those found for perceived stress. The implications of these findings for health-related media effects and theoretical development are discussed. PMID:26984375

  6. Seasonal and habitat-related distribution pattern of Synechococcus genotypes in Lake Constance.

    PubMed

    Becker, Sven; Richl, Petra; Ernst, Anneliese

    2007-10-01

    The abundance and distribution of Synechococcus spp. in the autotrophic picoplankton of Lake Constance, were followed in the pelagic and littoral habitat by qPCR over 2 years. One genotype, represented by isolated phycoerythrin-rich strain BO 8807, showed a seasonal distribution pattern in both habitats. Before a stable thermal stratification, the maximum of both the Synechococcus population and genotype BO 8807 occurred at 15 or 20 m water depth in the pelagic habitat. During the summer stratification, when the absolute abundance of all Synechococcus spp. was highest above 15 m, the absolute and relative abundance of genotype BO 8807 was maximal at 20 m. These results indicate that Synechococcus spp. or single genotypes are present in deep maxima in Lake Constance. The in situ dynamics of genotype BO 8807 is consistent with the observation that isolated strain BO 8807 requires higher phosphate concentrations for maximum growth rates than a strain from the same phylogenetic cluster that dominates the pelagic summer population. In contrast to these findings, low genome numbers of phycocyanin-rich genotype BO 8805 were found temporarily only in both the littoral and pelagic plankton. Microscopy revealed that PC-rich cells in general occurred preferentially in the littoral habitat. We discuss our results with respect to the versatility of picocyanobacteria of the evolutionary lineage VI of cyanobacteria, and a habitat-related distribution pattern of Synechococcus genotypes. PMID:17825073

  7. The relation between recombination rate and patterns of molecular evolution and variation in Drosophila melanogaster.

    PubMed

    Campos, José L; Halligan, Daniel L; Haddrill, Penelope R; Charlesworth, Brian

    2014-04-01

    Genetic recombination associated with sexual reproduction increases the efficiency of natural selection by reducing the strength of Hill-Robertson interference. Such interference can be caused either by selective sweeps of positively selected alleles or by background selection (BGS) against deleterious mutations. Its consequences can be studied by comparing patterns of molecular evolution and variation in genomic regions with different rates of crossing over. We carried out a comprehensive study of the benefits of recombination in Drosophila melanogaster, both by contrasting five independent genomic regions that lack crossing over with the rest of the genome and by comparing regions with different rates of crossing over, using data on DNA sequence polymorphisms from an African population that is geographically close to the putatively ancestral population for the species, and on sequence divergence from a related species. We observed reductions in sequence diversity in noncrossover (NC) regions that are inconsistent with the effects of hard selective sweeps in the absence of recombination. Overall, the observed patterns suggest that the recombination rate experienced by a gene is positively related to an increase in the efficiency of both positive and purifying selection. The results are consistent with a BGS model with interference among selected sites in NC regions, and joint effects of BGS, selective sweeps, and a past population expansion on variability in regions of the genome that experience crossing over. In such crossover regions, the X chromosome exhibits a higher rate of adaptive protein sequence evolution than the autosomes, implying a Faster-X effect. PMID:24489114

  8. Closely Related Fishes Inhabiting Different Ecosystems Exhibit the Same Oocyte Production and Recruitment Pattern.

    PubMed

    Costa, Eudriano F S; Dias, June F; Murua, Hilario

    2016-04-01

    Information on oocyte production and recruitment in phylogenetically related species can help in understanding the evolution of reproductive life-history traits in fish of indeterminate fecundity. The present study compared, for the first time, oocyte production and recruitment patterns between two closely related species: Stellifer brasiliensis and Stellifer rastrifer (Perciformes, Sciaenidae), in the southwestern Atlantic, Brazil. Specimens of S. brasiliensis were sampled from the coastal waters of Ubatuba, and samples of S. rastrifer were taken from the Cananéia Lagoon Estuarine System. Ovaries were investigated using histology and model-based stereology. The total number of oocytes per individual (N) and stage-specific oocyte packing density did not differ significantly between S. brasiliensis and S. rastrifer The number of pre-vitellogenic and vitellogenic oocytes were positively correlated with female total weight and length, and ovary weight in both species. Analysis of oocyte recruitment across their development stages revealed that approximately 5.9% of the standing stock oocytes larger than 50 μm in S. brasiliensis and 5.0% in S. rastrifer were recruited to form the next batches. Females of S. brasiliensis and S. rastrifer, in spawning-capable phase, exhibit the same oocyte production and recruitment patterns, showing no influences of the ecosystems on primary and secondary oocyte production. PMID:27132132

  9. Erosional patterns of the Isles Dernieres, Louisiana, in relation to meteorological influences

    USGS Publications Warehouse

    Dingler, J.R.; Reiss, T.E.; Plant, N.G.

    1993-01-01

    Over the past 100 years, the Isles Dernieres, a low-lying barrier-island chain along the central Louisiana coast, has eroded extensively. This erosion has resulted in more than 1 km of northward beach-face retreat and the loss of 71% of the total island area. The primary causes for the erosion are wind and wave attack, diminished sand supply, and relative sea-level rise. Five years of detailed topographic surveys show that a beach on the central Isles Dernieres changed significantly in both shape and sediment volume; however, the pattern of change was not the same each year. In contrast to the relatively slow erosion caused by cold fronts, hurricane Gilbert, a category 5 hurricane that passed about 800 km south of the Isles Dernieres in September 1988, produced differential beach-face retreat of about 9 m at mean sea level and 40 m at an elevation of 0.5 m. Most of the sediment eroded from the beach face was deposited on the backshore, which resulted in only a small loss of sediment from the beach and a noteworthy decrease in beach-face slope. During the two years following hurricane Gilbert, the mean-sea-level contour remained stationary while the beach face slowly returned to its pre-Gilbert shape. "Cold-front' magnitude of retreat is expected to continue until another large hurricane alters the erosional pattern. -from Authors

  10. Movement-related cortical potentials in paraplegic patients: abnormal patterns and considerations for BCI-rehabilitation

    PubMed Central

    Xu, Ren; Jiang, Ning; Vuckovic, Aleksandra; Hasan, Muhammad; Mrachacz-Kersting, Natalie; Allan, David; Fraser, Matthew; Nasseroleslami, Bahman; Conway, Bernie; Dremstrup, Kim; Farina, Dario

    2014-01-01

    Non-invasive EEG-based Brain-Computer Interfaces (BCI) can be promising for the motor neuro-rehabilitation of paraplegic patients. However, this shall require detailed knowledge of the abnormalities in the EEG signatures of paraplegic patients. The association of abnormalities in different subgroups of patients and their relation to the sensorimotor integration are relevant for the design, implementation and use of BCI systems in patient populations. This study explores the patterns of abnormalities of movement related cortical potentials (MRCP) during motor imagery tasks of feet and right hand in patients with paraplegia (including the subgroups with/without central neuropathic pain (CNP) and complete/incomplete injury patients) and the level of distinctiveness of abnormalities in these groups using pattern classification. The most notable observed abnormalities were the amplified execution negativity and its slower rebound in the patient group. The potential underlying mechanisms behind these changes and other minor dissimilarities in patients’ subgroups, as well as the relevance to BCI applications, are discussed. The findings are of interest from a neurological perspective as well as for BCI-assisted neuro-rehabilitation and therapy. PMID:25221505

  11. Seasonal variation in daily activity patterns of free-ranging European ground squirrels (Spermophilus citellus).

    PubMed

    Everts, Lammina G; Strijkstra, Arjen M; Hut, Roelof A; Hoffmann, Ilse E; Millesi, Eva

    2004-01-01

    Daily aboveground activity of European ground squirrels (Spermophilus citellus) in their natural habitat was recorded with a visual scanning procedure during the active seasons of 1992 and 1993. Activity patterns were analyzed with respect to time of year and to the animal's reproductive state. Aboveground activity started on average 3.9 h (SD 0.6 h, n = 37 days) after civil twilight at dawn and ended on average 3.2 h (SD 0.9 h, n = 37 days) before civil twilight at dusk. Between onset and offset of activity, 54% was spent aboveground, of which 73% was spent foraging. Activity patterns were influenced by photoperiod, rainfall, and by reproductive state. During mating, reproductively active males started activity earlier than females and reproductively inactive males. For females, time spent foraging was high during lactation. The midpoint of daily activity was at 12:16 h (SD 0.37 h, n = 37 days). Activity patterns of European ground squirrels thus appear robustly positioned in the middle of the photoperiod. PMID:15129824

  12. Movement-related cortical activation in familial Parkinson disease.

    PubMed

    Delval, A; Defebvre, L; Labyt, E; Douay, X; Bourriez, J-L; Waucquiez, N; Derambure, P; Destée, A

    2006-09-26

    We sought to determine whether or not first-degree relatives of patients with familial Parkinson disease (FDRs) present impaired movement-related cortical activity. We studied 10 familial Parkinson disease subjects, 10 FDRs, and 10 controls and analyzed event-related mu desynchronization (ERD) and beta synchronization. Forty percent FDRs presented reduced premovement mu ERD latency, suggesting that premovement cortical activation is impaired in FDRs. PMID:17000986

  13. Injury patterns in aviation-related fatalities. Implications for preventive strategies.

    PubMed

    Li, G; Baker, S P

    1997-09-01

    Autopsy data from individual aviation crashes have long been used in aviation safety research in the form of case reports and case series studies. Injuries sustained from aviation crashes, however, have not been well documented at a national level. This study examines the injury patterns for persons who died in aviation crashes in the United States and the implications for preventive strategies. Death certificate data for all aviation-related fatalities for the years 1980 (n = 1,543) and 1990 (n = 1.011) were obtained from the National Center for Health Statistics. The immediate cause of death and all injury diagnoses recorded on the death certificates were analyzed in relation to year of injury, crash category, and type of victim. Despite a 34% reduction in the number of aviation-related fatalities between 1980 and 1990, injury patterns were fairly stable. Multiple injuries were listed as the immediate cause of death in 42% of the fatalities, followed by head injury (22%); internal injury of thorax, abdomen, or pelvis (12%); burns (4%); and drowning (3%). Head injuries were most common among children. The majority (86%) died at the scene or were dead on arrival at the hospital. Eighteen percent of the victims were reported to have sustained a single injury, with head injury being the cause of death in nearly a third of these fatalities. Blunt injuries resulting from deceleration forces, in particular head injury, are still the most important hazard threatening occupants' survival in aviation crashes. To further reduce aviation-related fatalities requires more effective restraint systems and o