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Sample records for activity pa patterns

  1. Physical activity (PA) among middle-aged women: initial and current influences and patterns of participation.

    PubMed

    Codina, Nuria; Pestana, José V; Armadans, Immaculada

    2013-01-01

    This study investigated the initial and current influences for doing physical activity (PA), current levels of PA participation, and future plans for it. Participants were 200 women aged 45 to 64 years old. Factor loadings of influences were explored using Principal Components Analysis. Pearson bivariate correlations, t-test, and ANOVA were used to show the differences among the influences, sociodemographic characteristics, and present/future PA participation. Personal fulfillment was the main initial influence, while health benefits/self-care, and outdoor/family activities were the most important current influences. The results highlight the factors that best explain present PA participation and also plans for activity in the future.

  2. Proteasome activators, PA28γ and PA200, play indispensable roles in male fertility.

    PubMed

    Huang, Lin; Haratake, Kousuke; Miyahara, Hatsumi; Chiba, Tomoki

    2016-03-22

    Protein degradation mediated by the proteasome is important for the protein homeostasis. Various proteasome activators, such as PA28 and PA200, regulate the proteasome function. Here we show double knockout (dKO) mice of Psme3 and Psme4 (genes for PA28γ and PA200), but not each single knockout mice, are completely infertile in male. The dKO sperms exhibited remarkable defects in motility, although most of them showed normal appearance in morphology. The proteasome activity of the mutant sperms decreased notably, and the sperms were strongly positive with ubiquitin staining. Quantitative analyses of proteins expressed in dKO sperms revealed up-regulation of several proteins involved in oxidative stress response. Furthermore, increased 8-OHdG staining was observed in dKO sperms head, suggesting defective response to oxidative damage. This report verified PA28γ and PA200 play indispensable roles in male fertility, and provides a novel insight into the role of proteasome activators in antioxidant response.

  3. Proteasome activators, PA28γ and PA200, play indispensable roles in male fertility

    PubMed Central

    Huang, Lin; Haratake, Kousuke; Miyahara, Hatsumi; Chiba, Tomoki

    2016-01-01

    Protein degradation mediated by the proteasome is important for the protein homeostasis. Various proteasome activators, such as PA28 and PA200, regulate the proteasome function. Here we show double knockout (dKO) mice of Psme3 and Psme4 (genes for PA28γ and PA200), but not each single knockout mice, are completely infertile in male. The dKO sperms exhibited remarkable defects in motility, although most of them showed normal appearance in morphology. The proteasome activity of the mutant sperms decreased notably, and the sperms were strongly positive with ubiquitin staining. Quantitative analyses of proteins expressed in dKO sperms revealed up-regulation of several proteins involved in oxidative stress response. Furthermore, increased 8-OHdG staining was observed in dKO sperms head, suggesting defective response to oxidative damage. This report verified PA28γ and PA200 play indispensable roles in male fertility, and provides a novel insight into the role of proteasome activators in antioxidant response. PMID:27003159

  4. Tissue Plasminogen Activator (tPA) Mediates Neurotoxin-Induced Cell Death and Microglial Activation

    DTIC Science & Technology

    2001-07-01

    Alzheimer’s disease and stroke. Tissue plasminogen activator (tPA), a protease converting plasminogen to plasmin, is necessary for neurodegeneration. In mice lacking tPA (tPA-/1), neurons are resistant to neurotoxic death. Delivery of tPA into tpA-/- mice restores susceptibility to neuronal death, indicating that tPA is neurotoxic in the context of excitotoxic injury. Although tPA is synthesized by neurons, the increase in tPA upon injury derives primarily from activated microglia, the immune cells of the brain. Microglia in tPA-/- mice demonstrate reduced activation.

  5. Proteasome Activators, PA28α and PA28β, Govern Development of Microvascular Injury in Diabetic Nephropathy and Retinopathy

    PubMed Central

    Mahmoudpour, Ali

    2016-01-01

    Diabetic nephropathy (DN) and diabetic retinopathy (DR) are major complications of type 1 and type 2 diabetes. DN and DR are mainly caused by injury to the perivascular supporting cells, the mesangial cells within the glomerulus, and the pericytes in the retina. The genes and molecular mechanisms predisposing retinal and glomerular pericytes to diabetic injury are poorly characterized. In this study, the genetic deletion of proteasome activator genes, PA28α and PA28β genes, protected the diabetic mice in the experimental STZ-induced diabetes model against renal injury and retinal microvascular injury and prolonged their survival compared with wild type STZ diabetic mice. The improved wellbeing and reduced renal damage was associated with diminished expression of Osteopontin (OPN) and Monocyte Chemoattractant Protein-1 (MCP-1) in the glomeruli of STZ-injected PA28α/PA28β double knockout (Pa28αβDKO) mice and also in cultured mesangial cells and retinal pericytes isolated from Pa28αβDKO mice that were grown in high glucose. The mesangial PA28-mediated expression of OPN under high glucose conditions was suppressed by peptides capable of inhibiting the binding of PA28 to the 20S proteasome. Collectively, our findings demonstrate that diabetic hyperglycemia promotes PA28-mediated alteration of proteasome activity in vulnerable perivascular cells resulting in microvascular injury and development of DN and DR. PMID:27830089

  6. 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.…

  7. Crystal structure of an avian influenza polymerase PA[subscript N] reveals an endonuclease active site

    SciTech Connect

    Yuan, Puwei; Bartlam, Mark; Lou, Zhiyong; Chen, Shoudeng; Zhou, Jie; He, Xiaojing; Lv, Zongyang; Ge, Ruowen; Li, Xuemei; Deng, Tao; Fodor, Ervin; Rao, Zihe; Liu, Yingfang

    2009-11-10

    The heterotrimeric influenza virus polymerase, containing the PA, PB1 and PB2 proteins, catalyses viral RNA replication and transcription in the nucleus of infected cells. PB1 holds the polymerase active site and reportedly harbours endonuclease activity, whereas PB2 is responsible for cap binding. The PA amino terminus is understood to be the major functional part of the PA protein and has been implicated in several roles, including endonuclease and protease activities as well as viral RNA/complementary RNA promoter binding. Here we report the 2.2 angstrom (A) crystal structure of the N-terminal 197 residues of PA, termed PA(N), from an avian influenza H5N1 virus. The PA(N) structure has an alpha/beta architecture and reveals a bound magnesium ion coordinated by a motif similar to the (P)DX(N)(D/E)XK motif characteristic of many endonucleases. Structural comparisons and mutagenesis analysis of the motif identified in PA(N) provide further evidence that PA(N) holds an endonuclease active site. Furthermore, functional analysis with in vivo ribonucleoprotein reconstitution and direct in vitro endonuclease assays strongly suggest that PA(N) holds the endonuclease active site and has critical roles in endonuclease activity of the influenza virus polymerase, rather than PB1. The high conservation of this endonuclease active site among influenza strains indicates that PA(N) is an important target for the design of new anti-influenza therapeutics.

  8. FracPaQ: A MATLAB™ toolbox for the quantification of fracture patterns

    NASA Astrophysics Data System (ADS)

    Healy, David; Rizzo, Roberto E.; Cornwell, David G.; Farrell, Natalie J. C.; Watkins, Hannah; Timms, Nick E.; Gomez-Rivas, Enrique; Smith, Michael

    2017-02-01

    The patterns of fractures in deformed rocks are rarely uniform or random. Fracture orientations, sizes, and spatial distributions often exhibit some kind of order. In detail, relationships may exist among the different fracture attributes, e.g. small fractures dominated by one orientation, larger fractures by another. These relationships are important because the mechanical (e.g. strength, anisotropy) and transport (e.g. fluids, heat) properties of rock depend on these fracture attributes and patterns. This paper describes FracPaQ, a new open source, cross-platform toolbox to quantify fracture patterns, including distributions in fracture attributes and their spatial variation. Software has been developed to quantify fracture patterns from 2-D digital images, such as thin section micrographs, geological maps, outcrop or aerial photographs or satellite images. The toolbox comprises a suite of MATLAB™ scripts based on previously published quantitative methods for the analysis of fracture attributes: orientations, lengths, intensity, density and connectivity. An estimate of permeability in 2-D is made using a parallel plate model. The software provides an objective and consistent methodology for quantifying fracture patterns and their variations in 2-D across a wide range of length scales, rock types and tectonic settings. The implemented methods presented are inherently scale independent, and a key task where applicable is analysing and integrating quantitative fracture pattern data from micro-to macro-scales. The toolbox was developed in MATLAB™ and the source code is publicly available on GitHub™ and the Mathworks™ FileExchange. The code runs on any computer with MATLAB installed, including PCs with Microsoft Windows, Apple Macs with Mac OS X, and machines running different flavours of Linux. The application, source code and sample input files are available in open repositories in the hope that other developers and researchers will optimise and extend the

  9. A novel plasminogen activator from Agkistrodon blomhoffii Ussurensis venom (ABUSV-PA): purification and characterization.

    PubMed

    Liu, Shuqing; Sun, Ming-Zhong; Greenaway, Frederick T

    2006-10-06

    A plasminogen activator with arginine ester hydrolysis activity (ABUSV-PA) has been identified and purified to homogeneity from Chinese Agkistrodon blomhoffii Ussurensis snake venom. ABUSV-PA, a monomeric protein with molecular mass of 27815.2 Da, was purified 180-fold with 0.02% recovery for protein and 3.6% recovery for esterase activity. ABUSV-PA reacts optimally with its substrate N(alpha)-tosyl-l-arginine-methyl ester (TAME) at approximately pH 7.5 and at 51 degrees C. Measurement from inductively coupled plasma-atomic emission spectroscopy (ICP-AES) reveals that ABUSV-PA is a Zn(2+)-containing protein with a stoichiometry of 1:1 [Zn(2+)]:[ABUSV-PA]. Analyses of esterase hydrolysis and UV absorption and CD spectra indicate that Zn(2+) plays an important role in maintaining the structural integrity rather than the esterase activity of ABUSV-PA. Divalent metal ions, including Ca(2+), Mg(2+), Cu(2+), Ni(2+), Mn(2+), and Co(2+), increase the TAME hydrolysis activity of ABUSV-PA. A red-shift of the emission wavelengths of the synchronous fluorescence of ABUSV-PA, compared to those of free Tyr and Trp, indicates a conformation where the Tyr and Trp residues are in exposed hydrophilic environments. The presence of zinc increases the hydrophobicity of the conformational environments surrounding the Trp residues of ABUSV-PA and affects the secondary structure of ABUSV-PA, as proved by UV absorption and CD spectroscopy.

  10. Genomic structural characterization and transcriptional expression analysis of proteasome activator PA28α and PA28β subunits from Oplegnathus fasciatus.

    PubMed

    Kasthuri, Saranya Revathy; Umasuthan, Navaneethaiyer; Whang, Ilson; Kim, Eunmi; Park, Hae-Chul; Lee, Jehee

    2013-10-01

    Proteasomes are multicatalytic subunit complexes involved in the degradation of cytosolic proteins and antigen presentation. In this study, we have characterized the alpha and beta subunits of proteasome activator complex from rock bream at the molecular level. RbPA28α and RbPA28β possessed the characteristic features of the subunits identified from mammals and teleosts. The RbPA28α and RbPA28β proteasome subunits contained a proline-rich motif (Region A), subunit-specific insert in the region corresponding to the KEKE motif of the known PA28α (Region B), conserved activation loop (Region C), a potential protein kinase C recognition site (Region D) and a highly homologous C-terminal region (Region E) among all three PA28 subunits. Multiple sequence alignment and pairwise alignment revealed that RbPA28α and RbPA28β proteins shared high homology with the teleosts and mammals. RbPA28α and RbPA28β genome possessed 11 exons interrupted by 10 introns. In silico promoter analysis of RbPA28α and RbPA28β revealed various transcription factor-binding sites displaying their regulation under various stress conditions. Tissue distribution profiling showed a higher expression in blood and gills. Transcriptional expression analysis of RbPA28α and RbPA28β showed up-regulation in the immune tissues following LPS and poly I:C challenges, providing further evidence for the immunological role of RbPA28α and RbPA28β.

  11. 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.

  12. Interaction between plasminogen activator inhibitor type 1 (PAI-1) bound to fibrin and either tissue-type plasminogen activator (t-PA) or urokinase-type plasminogen activator (u-PA). Binding of t-PA/PAI-1 complexes to fibrin mediated by both the finger and the kringle-2 domain of t-PA.

    PubMed Central

    Wagner, O F; de Vries, C; Hohmann, C; Veerman, H; Pannekoek, H

    1989-01-01

    Plasminogen activation is catalyzed both by tissue-type-(t-PA) and by urokinase-type plasminogen activator (u-PA). This reaction is controlled by plasminogen activator inhibitor type 1 (PAI-1) that is either present in plasma or bound to fibrin, present in a thrombus. We studied the mechanism of in vitro inhibition of both t-PA and u-PA activity by PAI-1 bound to fibrin. It is shown that activation of latent PAI-1 unmasks a specific fibrin-binding site that is distinct from its reactive site. This reactive site of activated PAI-1 bound to fibrin is fully exposed to form complexes with t-PA and u-PA, that are unable to activate plasminogen. Upon complex formation with either one of the plasminogen activators, PAI-1 apparently undergoes a conformational change and loses its affinity for fibrin. Consequently, complexes of u-PA and PAI-1 dissociate from the fibrin matrix and are encountered in the fluid phase. In contrast, t-PA/PAI-1 complexes remain bound to fibrin. By employing recombinant t-PA deletion-mutant proteins, that precisely lack domains involved in fibrin binding, we demonstrate that binding of t-PA/PAI-1 complexes is mediated by both the "finger" (F) and the "kringle-2" (K2) domain of t-PA. A model is proposed that explains inhibition of the fibrinolytic process, at the level of plasminogen activation by t-PA, directed by PAI-1 bound to fibrin. An implication of the proposed model is that t-PA/PAI-1 complexes and free t-PA compete for the same binding sites on fibrin. Images PMID:2503541

  13. 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…

  14. Thrombolytic efficacy and enzymatic activity of rt-PA-loaded echogenic liposomes.

    PubMed

    Bader, Kenneth B; Bouchoux, Guillaume; Peng, Tao; Klegerman, Melvin E; McPherson, David D; Holland, Christy K

    2015-08-01

    Echogenic liposomes (ELIP), that can encapsulate both recombinant tissue-type plasminogen activator (rt-PA) and microbubbles, are under development to improve the treatment of thrombo-occlusive disease. However, the enzymatic activity, thrombolytic efficacy, and stable cavitation activity generated by this agent has yet to be evaluated and compared to another established ultrasound-enhanced thrombolytic scheme. A spectrophotometric method was used to compare the enzymatic activity of the rt-PA incorporated into ELIP (t-ELIP) to that of rt-PA. An in vitro flow model was employed to measure the thrombolytic efficacy and dose of ultraharmonic emissions from stable cavitation for 120-kHz ultrasound exposure of three treatment schemes: rt-PA, rt-PA and the perfluorocarbon-filled microbubble Definity(®), and t-ELIP. The enzymatic activity of rt-PA incorporated into t-ELIP was 28 % that of rt-PA. Thrombolytic efficacy of t-ELIP or rt-PA and Definity(®) was equivalent when the dose of t-ELIP was adjusted to produce comparable enzymatic activity. Sustained bubble activity was nucleated from Definity but not from t-ELIP exposed to 120-kHz ultrasound. These results emphasize the advantages of encapsulating a thrombolytic and the importance of incorporating an insoluble gas required to promote sustained, stable cavitation activity.

  15. Plasma tPA-Activity and Progression of Cerebral White Matter Hyperintensities in Lacunar Stroke Patients

    PubMed Central

    van Overbeek, Ellen C.; Staals, Julie; Knottnerus, Iris L. H.; ten Cate, Hugo; van Oostenbrugge, Robert J.

    2016-01-01

    Introduction Tissue plasminogen activator (tPA)-activity and plasminogen activator inhibitor type 1 (PAI-1) antigen are considered to be haemostasis-related markers of endothelial activation and relate to presence of cerebral white matter hyperintensities (WMH) as was earlier shown in a cross-sectional study. We investigated whether tPA-activity and PAI-1 levels are associated with WMH progression in a longitudinal study. Methods In 127 first-ever lacunar stroke patients in whom baseline brain MRI and plasma levels of tPA-activity and PAI-1-antigen were available, we obtained a 2-year follow-up MRI. We assessed WMH progression by a visual WMH change scale. We determined the relationship between levels of tPA-activity and PAI-1 and WMH progression, by logistic regression analysis. Results Plasma tPA-activity was associated with periventricular WMH progression (OR 2.36, 95% CI 1.01–5.49, with correction for age and sex and baseline presence of WMH), but not with deep or any (periventricular and/or deep) WMH progression. PAI-1 levels were lower in patients with WMH progression, but these results were not significant. Conclusion We found a relationship between plasma tPA-activity and progression of periventricular WMH. More research is needed to determine whether there is a (direct) role of tPA in the development and progression of WMH. PMID:26942412

  16. 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,…

  17. Molecular and functional characterization of a putative PA28γ proteasome activator orthologue in Schistosoma mansoni.

    PubMed

    Soares, Cláudia Sossai; Morais, Enyara Rezende; Magalhães, Lizandra G; Machado, Carla Botelho; Moreira, Érika Bueno de Carvalho; Teixeira, Felipe Roberti; Rodrigues, Vanderlei; Yoshino, Timothy P

    2013-05-01

    PA28γ is a proteasome activator involved in the regulation of the cellular proliferation, differentiation and growth. In the present study, we identified and characterized a cDNA from Schistosoma mansoni exhibiting significant homology to PA28γ of diverse taxa ranging from mammals (including humans) to simple invertebrates. Designated SmPA28γ, this transcript has a 753bp predicted ORF encoding a protein of 250 amino acid residues. Alignment of SmPA28γ with multiple PA28γ orthologues revealed an average similarity of ~40% among the investigated organisms, and 90% similarity with PA28γ from Schistosoma japonicum. In addition, phylogenetic analysis demonstrated a close linkage between SmPA28γ to its sister group that contains well-characterized PA28γ sequences from Drosophila spp., as well as sharing the same branch with PA28γ from S. japonicum. Gene expression profiling of SmPA28γ using real-time quantitative PCR revealed elevated steady-state transcript levels in the eggs, miracidia and paired adult worms compared to other stages. In parallel with gene expression profiles, an affinity-purified anti-SmPA28γ antibody produced against recombinant protein exhibited strongest reactivity in Western blot analyses to endogenous SmPA28γ from miracidia, sporocysts and paired adult worms. Given its known regulatory function in other organisms, we hypothesized that the high level of SmPA28γ transcript and protein in these stages may be correlated with an important role of the PA28γ in the cellular growth and/or development of this parasite. To address this hypothesis, miracidia were transformed in vitro to sporocysts in the presence of SmPA28γ double-stranded RNAs (dsRNAs) and cultivated for 4 days, after which time steady-state transcript and protein levels, and phenotypic changes were evaluated. SmPA28γ dsRNA treatment resulted in gene and protein knockdown of ~60% and ~80%, respectively, which were correlated with a significant decrease in larval length

  18. Inhibition of PA endonuclease activity of influenza virus RNA polymerase by Kampo medicines.

    PubMed

    Shirayama, Riku; Shoji, Masaki; Sriwilaijaroen, Nongluk; Hiramatsu, Hiroaki; Suzuki, Yasuo; Kuzuhara, Takashi

    To find a novel influenza inhibitor targeting the endonuclease activity of influenza A virus polymerase acidic protein (PA), which is essential for the acquisition of primers for viral mRNA transcription, seven Kampo extracts were tested in vitro for their ability to inhibit endonuclease activity of the recombinant PA protein that was expressed and purified from Escherichia coli. The Kampo medicines Kakkonto, Shosaikoto, Saikokeishito, Keishito, Maobushisaishinto, and Maoto, but not Chikujountanto, inhibited PA endonuclease activity in a dose-dependent manner. Our results indicate that Kampo medicines are good sources providing a structural lead for optimization of an influenza endonuclease inhibitor.

  19. A novel plasminogen activator from Agkistrodon blomhoffii Ussurensis venom (ABUSV-PA): Purification and characterization

    SciTech Connect

    Liu Shuqing; Sun Mingzhong . E-mail: ming-zhong.sun@case.edu; Greenaway, Frederick T.

    2006-10-06

    A plasminogen activator with arginine ester hydrolysis activity (ABUSV-PA) has been identified and purified to homogeneity from Chinese Agkistrodon blomhoffii Ussurensis snake venom. ABUSV-PA, a monomeric protein with molecular mass of 27815.2 Da, was purified 180-fold with 0.02% recovery for protein and 3.6% recovery for esterase activity. ABUSV-PA reacts optimally with its substrate N {sub {alpha}}-tosyl-L-arginine-methyl ester (TAME) at {approx}pH 7.5 and at 51 {sup o}C. Measurement from inductively coupled plasma-atomic emission spectroscopy (ICP-AES) reveals that ABUSV-PA is a Zn{sup 2+}-containing protein with a stoichiometry of 1:1 [Zn{sup 2+}]:[ABUSV-PA]. Analyses of esterase hydrolysis and UV absorption and CD spectra indicate that Zn{sup 2+} plays an important role in maintaining the structural integrity rather than the esterase activity of ABUSV-PA. Divalent metal ions, including Ca{sup 2+}, Mg{sup 2+}, Cu{sup 2+}, Ni{sup 2+}, Mn{sup 2+}, and Co{sup 2+}, increase the TAME hydrolysis activity of ABUSV-PA. A red-shift of the emission wavelengths of the synchronous fluorescence of ABUSV-PA, compared to those of free Tyr and Trp, indicates a conformation where the Tyr and Trp residues are in exposed hydrophilic environments. The presence of zinc increases the hydrophobicity of the conformational environments surrounding the Trp residues of ABUSV-PA and affects the secondary structure of ABUSV-PA, as proved by UV absorption and CD spectroscopy.

  20. Impacts of tissue-type plasminogen activator (tPA) on neuronal survival

    PubMed Central

    Chevilley, Arnaud; Lesept, Flavie; Lenoir, Sophie; Ali, Carine; Parcq, Jérôme; Vivien, Denis

    2015-01-01

    Tissue-type plasminogen activator (tPA) a serine protease is constituted of five functional domains through which it interacts with different substrates, binding proteins, and receptors. In the last years, great interest has been given to the clinical relevance of targeting tPA in different diseases of the central nervous system, in particular stroke. Among its reported functions in the central nervous system, tPA displays both neurotrophic and neurotoxic effects. How can the protease mediate such opposite functions remain unclear but several hypotheses have been proposed. These include an influence of the degree of maturity and/or the type of neurons, of the level of tPA, of its origin (endogenous or exogenous) or of its form (single chain tPA versus two chain tPA). In this review, we will provide a synthetic snapshot of our current knowledge regarding the natural history of tPA and discuss how it sustains its pleiotropic functions with focus on excitotoxic/ischemic neuronal death and neuronal survival. PMID:26528141

  1. Labeling of human clots in vitro with an active-site mutant of t-PA

    SciTech Connect

    Fry, E.T.; Mack, D.L.; Monge, J.C.; Billadello, J.J.; Sobel, B.E. )

    1990-02-01

    Prompt detection of acute thrombosis and its response to treatment with thrombolytic agents generally require angiography. Scintigraphic approaches with labeled antibodies to or components of the coagulation and fibrinolytic systems have been disappointing because of prolonged circulating half-lives of tracers and relatively slow or limited binding to thrombi. Accordingly, we developed and characterized a thrombolytically inactive, active-site mutant (Ser-478----Thr) of tissue-type plasminogen activator (t-PA) designed to detect thrombi in vivo. Binding of iodine-125-({sup 125}I) labeled Ser----Thr t-PA to thrombi in vitro was time- and concentration-dependent, and specific judging from inhibition by pre-incubation with anti-t-PA IgG. Clearance of 125I-labeled mutant t-PA in rabbits was rapid and biexponential (alpha t1/2 = 1.9 +/- 0.4 min, beta t1/2 = 39.8 +/- 11.2 min). Thus, the amidolytically inactive mutant of t-PA designed binds rapidly and specifically to human thrombi in vitro and is cleared rapidly from the circulation in vivo--properties rendering it attractive as a potentially useful clot imaging agent.

  2. Patterns and Associated Factors of Physical Activity among Adolescents in Nigeria

    PubMed Central

    Oyeyemi, Adewale L.; Ishaku, Cornelius M.; Oyekola, Jameela; Wakawa, Hajara D.; Lawan, Aliyu; Yakubu, Safira; Oyeyemi, Adetoyeje Y.

    2016-01-01

    Introduction Understanding the context where adolescents’ physical activity (PA) takes place could impact a more targeted approach to implement PA promotion and interventions in Africa. However, standardized data on adolescents’ PA behaviour is lacking in Nigeria. We described PA patterns in the various domains (home, school, transport, leisure-time) and intensity categories (light-intensity PA, moderate- to vigorous- intensity physical activity [MVPA] and total PA), and their associations with sociodemographic factors and socioeconomic status (SES) among secondary school adolescents in Nigeria. Methods A cross-sectional survey was conducted in a representative sample of 1006 secondary school adolescents (12–18 years, 50.4% girls) in Maiduguri, Nigeria. Self-reported PA was assessed with an adapted version of the Activity Questionnaire for Adolescents and Young Adults. Outcomes were weekly minutes (min/wk) of PA spent in the various domains and intensity categories. Multivariate ANOVA was used to examine associations of PA scores (domains and intensity levels) with adolescents’ sociodemographic characteristics and SES, and track differences in PA scores between subgroups. Results The total sample reported most PA at school (1525 min/wk), the least during active transportation (210 min/wk), and only 37% engaged in 60 min of MVPA daily. Boys reported significantly more leisure-time PA (P<0.001), active transportation (P<0.001), MVPA (P = 0.023) and total PA (P = 0.003) than girls, while girls reported more school-based PA (P = 0.009), home-based PA (P<0.001) and light-intensity PA (P<0.001) than boys. Moderate-intensity PA (P = 0.024) and total PA (P = 0.049) were significantly higher in younger age group than in older group. Household car ownership was associated with less active transportation (P = 0.009), less moderate-intensity PA (P = 0.048) and with more leisure-time PA (P = 0.013). High parental SES was associated with more leisure-time PA (P = 0

  3. Psychological correlates of self-reported and objectively measured physical activity among Chinese children—psychological correlates of PA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study aimed to explore the associations among psychological correlates and physical activity (PA) in Chinese children and to further examine whether these associations varied by different PA measures. PA self-efficacy, motivation, and preference were reported in 449 8–13-year-old Chinese childr...

  4. PA28, an activator of the 20 S proteasome, is inactivated by proteolytic modification at its carboxyl terminus.

    PubMed

    Ma, C P; Willy, P J; Slaughter, C A; DeMartino, G N

    1993-10-25

    PA28, a protein activator of the 20 S proteasome, was previously identified in soluble extracts of bovine red blood cells (Ma, C.-P., Slaughter, C. A., and DeMartino, G. N. (1992) J. Biol. Chem. 267, 10515-10523). To determine whether this regulatory protein is as widely distributed as the proteasome, PA28 content and activity were examined in various eukaryotic tissues by immunoblot analysis and by functional assays of tissue extracts. PA28 protein was present in all sources examined. PA28 activity, however, was not detected in many of these sources, including those with the highest level of PA28 protein. To determine the biochemical basis of this result, PA28 was purified from extracts of rat liver, which had high levels of PA28 protein but no PA28 activity. The resulting purified PA28 had no detectable activity but had native and subunit molecular weights indistinguishable from the active PA28 of bovine red blood cells. Using the inactivation of purified PA28 as an assay, a protein that inactivated PA28 without altering its apparent molecular weight on SDS-polyacrylamide gel electrophoresis was identified, purified, and characterized from bovine liver. It had biochemical and catalytic characteristics similar to those of lysosomal carboxypeptidase B. When leupeptin, an inhibitor of lysosomal carboxypeptidase B, was included in the buffers used for the preparation of PA28, PA28 activity was detected in tissues which otherwise failed to demonstrate this activity. A similar result was obtained when extracts were prepared in a manner that minimized disruption of lysosomes. Other carboxypeptidases such as carboxypeptidase Y and pancreatic carboxypeptidase B also inactivated PA28 without altering its apparent molecular weight. Active PA28 binds to the proteasome to form a protease-activator complex that can be isolated after velocity sedimentation centrifugation through glycerol density gradients. Carboxypeptidase-inactivated PA28 failed to form such a complex

  5. Dynamic Patterns in Active Fluids

    NASA Astrophysics Data System (ADS)

    Jülicher, Frank

    2012-02-01

    Biological matter is inherently dynamic and exhibits active properties. A key example is the force generation by molecular motors in the cell cytoskeleton. Such active processes give rise to the generation of active mechanical stresses and spontaneous flows in gel-like cytoskeletal networks. Active material behaviors play a key role for the dynamics of cellular processes such as cell locomotion and cell division. We will discuss intracellular flow patterns that are created by active processes in the cell cortex. By combining theory with quantitative experiments we show that observed flow patterns result from profiles of active stress generation in the system. We will also consider the situation where active stress is regulated by a diffusing molecular species. In this case, spatial concentration patterns are generated by the interplay of stress regulation and self-generated flow fields.

  6. Spatial and temporal patterns in Cimex lectularius (Hemiptera: Cimicidae) reporting in Philadelphia, PA.

    PubMed

    Mabud, Tarub S; Barbarin, Alexis M; Barbu, Corentin M; Levy, Katelyn H; Edinger, Jason; Levy, Michael Z

    2014-01-01

    We analyzed a comprehensive telephone log of pest infestation reports to assess the spatial and temporal trends in Cimex lectularius L. (bed bug) reporting throughout Philadelphia, PA. Citywide spatial analyses of reports from September 2011 to June 2012 revealed several statistically significant bed bug hotspots. However, these were small and diffuse. Temporal analyses of reports from December 2008 to May 2011 detected prominent seasonality in bed bug reporting, peaking in August and reaching a nadir in February each year. Controlling for seasonal cycling, the number of bed bug reports in Philadelphia increased steadily at a rate of approximately 4.5% per month (or 69.45% per year) from December 2008 to May 2011. While it may be difficult to spatially target citywide bed bug control measures because of the insects' widespread migration, interventions informed by seasonal trends may enhance efforts to curb the recent increases in urban bed bug populations.

  7. Pyruvate and cilostazol protect cultured rat cortical pericytes against tissue plasminogen activator (tPA)-induced cell death.

    PubMed

    Kim, Ha Na; Kim, Tae-Youn; Yoon, Young Hee; Koh, Jae-Young

    2015-12-02

    Since even a brief ischemia can cause permanent brain damage, rapid restoration of blood flow is critical to limiting damage. Although intravenous tPA during the acute stage is the treatment of choice for achieving reperfusion, this treatment is sometimes associated with brain hemorrhage. Agents that reduce tPA-related bleeding risk may help expand its therapeutic window. This study assessed whether zinc dyshomeostasis underlies the toxic effect of tPA on brain vascular pericytes; whether pyruvate, an inhibitor of zinc toxicity, protects pericytes against tPA-induced cell death; and whether cilostazol, which protects pericytes against tPA-induced cell death, affects zinc dyshomeostasis associated with tPA toxicity. Cultured pericytes from newborn rat brains were treated with 10-200 μg/ml tPA for 24 h, inducing cell death in a concentration-dependent manner. tPA-induced cell death was preceded by increases in intracellular free zinc levels, and was substantially attenuated by plasminogen activator inhibitor-1 (PAI-1) or TPEN. Pyruvate completely blocked direct zinc toxicity and tPA-induced pericyte cell death. Both cAMP and cilostazol, a PDE3 inhibitor that attenuates tPA-induced pericyte cell death in vitro and tPA-induced brain hemorrhage in vivo, reduced zinc- and tPA-induced pericyte cell death, suggesting that zinc dyshomeostasis may be targeted by cilostazol in tPA toxicity. These findings show that tPA-induced pericyte cell death may involve zinc dyshomeostasis, and that pyruvate and cilostazol attenuate tPA-induced cell death by reducing the toxic cascade triggered by zinc dyshomeostasis. Since pyruvate is an endogenous metabolite and cilostazol is an FDA-approved drug, in vivo testing of both as protectors against tPA-induced brain hemorrhage may be warranted. This article is part of a Special Issue entitled SI: Neuroprotection.

  8. Gene therapy by proteasome activator, PA28γ, improves motor coordination and proteasome function in Huntington's disease YAC128 mice.

    PubMed

    Jeon, J; Kim, W; Jang, J; Isacson, O; Seo, H

    2016-06-02

    Huntington's disease (HD) is neurologically characterized by involuntary movements, associated with degeneration of the medium-sized spiny neurons (MSNs) and ubiquitin-positive neuronal intranuclear inclusions (NIIs). It has been reported that the proteolytic activities of the ubiquitin-proteasome system (UPS) are generally inhibited in HD patient's brain. We previously discovered that a proteasome activator (PA), PA28γ enhances proteasome activities and cell survival in in vitro HD model. In this study, we aimed to find whether PA28γ gene transfer improves the proteasome activities and pathological symptoms in in vivo HD model. We stereotaxically injected lenti-PA28γ virus into the striatum of mutant (MT) YAC128 HD mice and littermate (LM) controls at 14-18months of age, and validated their behavioral and biochemical changes at 12weeks after the injection. YAC128 mice showed a significant increase in their peptidyl-glutamyl preferring hydrolytic (PGPH) proteasome activity and the mRNA or protein levels of brain-derived neurotrophic factor (BDNF) and pro-BDNF after lenti-PA28γ injection. The number of ubiquitin-positive inclusion bodies was reduced in the striatum of YAC128 mice after lenti-PA28γ injection. YAC128 mice showed significant improvement of latency to fall on the rota-rod test after lenti-PA28γ injection. These data demonstrate that the gene therapy with PA, PA28γ can improve UPS function as well as behavioral abnormalities in HD model mice.

  9. Characterizing biofuel combustion with patterns of real-time emission data (PaRTED).

    PubMed

    Chen, Yanju; Roden, Christoph A; Bond, Tami C

    2012-06-05

    Emission properties and quantities from combustion sources can vary significantly during operation, and this characteristic variability is hidden in the traditional presentation of emission test averages. As a complement to the emission test averages, we introduce the notion of statistical pattern analysis to characterize temporal fluctuations in emissions, using cluster analysis and frequency plots. We demonstrate this approach by comparing emissions from traditional and improved wood-burning cookstoves under in-field conditions, and also to contrast laboratory and in-field cookstove performance. Compared with traditional cookstoves, improved cookstoves eliminate emissions that occur at low combustion efficiency. For cookstoves where the only improvement is an insulated combustion chamber, this change results in emission of more light-absorbing (black) particles. When a chimney is added, the stoves produce more black particles but also have reduced emission factors. Laboratory tests give different results than in-field tests, because they fail to reproduce a significant fraction of low-efficiency events, spikes in particulate matter (PM) emissions, and less-absorbing particles. These conditions should be isolated and replicated in future laboratory testing protocols to ensure that stove designs are relevant to in-use operation.

  10. Differences in resting metabolic rate and physical activity patterns in lean and overweight/obese pregnant women

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy requirements vary during pregnancy due to changes in physical activity (PA) and maternal fat stores. This study measured resting metabolic rate (RMR) and PA patterns in healthy lean and overweight/obese (OW) pregnant women. RMR was measured using indirect calorimetry (MOXUS), activity pattern...

  11. Intrinsic Patterns of Human Activity

    NASA Astrophysics Data System (ADS)

    Hu, Kun; Ivanov, Plamen Ch.; Chen, Zhi; Hilton, Michael; Stanley, H. Eugene; Shea, Steven

    2003-03-01

    Activity is one of the defining features of life. Control of human activity is complex, being influenced by many factors both extrinsic and intrinsic to the body. The most obvious extrinsic factors that affect activity are the daily schedule of planned events, such as work and recreation, as well as reactions to unforeseen or random events. These extrinsic factors may account for the apparently random fluctuations in human motion observed over short time scales. The most obvious intrinsic factors are the body clocks including the circadian pacemaker that influences our sleep/wake cycle and ultradian oscillators with shorter time scales [2, 3]. These intrinsic rhythms may account for the underlying regularity in average activity level over longer periods of up to 24 h. Here we ask if the known extrinsic and intrinsic factors fully account for all complex features observed in recordings of human activity. To this end, we measure activity over two weeks from forearm motion in subjects undergoing their regular daily routine. Utilizing concepts from statistical physics, we demonstrate that during wakefulness human activity possesses previously unrecognized complex dynamic patterns. These patterns of activity are characterized by robust fractal and nonlinear dynamics including a universal probability distribution and long-range power-law correlations that are stable over a wide range of time scales (from minutes to hours). Surprisingly, we find that these dynamic patterns are unaffected by changes in the average activity level that occur within individual subjects throughout the day and on different days of the week, and between subjects. Moreover, we find that these patterns persist when the same subjects undergo time-isolation laboratory experiments designed to account for the phase of the circadian pacemaker, and control the known extrinsic factors by restricting behaviors and manipulating scheduled events including the sleep/wake cycle. We attribute these newly

  12. Expression of the urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) in brain tissues of human immunodeficiency virus patients with opportunistic cerebral diseases.

    PubMed

    Nebuloni, Manuela; Cinque, Paola; Sidenius, Nicolai; Ferri, Angelita; Lauri, Eleonora; Omodeo-Zorini, Elisabetta; Zerbi, Pietro; Vago, Luca

    2009-01-01

    The urokinase plasminogen activator receptor (uPAR) and its ligand (uPA) play an important role in cell migration and extracellular proteolysis. We previously described uPAR/uPA overexpression in the cerebrospinal fluid (CSF) and brain tissues of patients with human immunodeficiency virus (HIV)-related cerebral diseases. In this study, we examined uPAR/uPA expression by immunohistochemistry (IHC) in brains of HIV patients with opportunistic cerebral lesions and in HIV-positive/negative controls. uPAR was found in macrophages/microglia with the highest levels in cytomegalovirus (CMV) encephalitis, toxoplasmosis, and lymphomas; in cryptococcosis and progressive multifocal leukoencephalopathy (PML) cases, only a few positive cells were found and no positivity was observed in controls. uPA expression was demonstrated only in a few macrophages/microglia and lymphocytes in all the cases and HIV-positive controls without different pattern of distribution; no uPA immunostaining was found in cryptococcosis and HIV-negative controls. The higher expression of uPAR/uPA in most of the opportunistic cerebral lesions supports their role in these diseases, suggesting their contribution to tissue injury.

  13. Expression and Biological Activity of the Cystine Knot Bioinsecticide PA1b (Pea Albumin 1 Subunit b)

    PubMed Central

    Eyraud, Vanessa; Karaki, Lamis; Rahioui, Isabelle; Sivignon, Catherine; Da Silva, Pedro; Rahbé, Yvan; Royer, Corinne; Gressent, Frédéric

    2013-01-01

    The PA1b (Pea Albumin 1, subunit b) peptide is an entomotoxin extract from Legume seeds with lethal activity on several insect pests, such as mosquitoes, some aphids and cereal weevils. This 37 amino-acid cysteine-rich peptide has been, until now, obtained by biochemical purification or chemical synthesis. In this paper, we present our results for the transient production of the peptide in Nicotiana benthamiana by agro-infiltration, with a yield of about 35 µg/g of fresh leaves and maximum production 8 days after infiltration. PA1b is part of the PA1 gene which, after post-translational modifications, encodes two peptides (PA1b and PA1a). We show that transforming tobacco with the PA1b cDNA alone does not result in production of the toxin and, in fact, the entire cDNA is necessary, raising the question of the role of PA1a. We constructed a PA1-cassette, allowing for the quick “cut/paste” of different PA1b mutants within a conserved PA1 cDNA. This cassette enabled us to produce the six isoforms of PA1b which exist in pea seeds. Biological tests revealed that all the isoforms display similar activity, with the exception of one which is inactive. The lack of activity in this isoform led us to conclude that the amphiphilic nature of the peptide is necessary for activity. The possible applications of this expression system for other cysteine-rich biomolecules are discussed. PMID:24349099

  14. Expression and biological activity of the cystine knot bioinsecticide PA1b (Pea Albumin 1 Subunit b).

    PubMed

    Eyraud, Vanessa; Karaki, Lamis; Rahioui, Isabelle; Sivignon, Catherine; Da Silva, Pedro; Rahbé, Yvan; Royer, Corinne; Gressent, Frédéric

    2013-01-01

    The PA1b (Pea Albumin 1, subunit b) peptide is an entomotoxin extract from Legume seeds with lethal activity on several insect pests, such as mosquitoes, some aphids and cereal weevils. This 37 amino-acid cysteine-rich peptide has been, until now, obtained by biochemical purification or chemical synthesis. In this paper, we present our results for the transient production of the peptide in Nicotiana benthamiana by agro-infiltration, with a yield of about 35 µg/g of fresh leaves and maximum production 8 days after infiltration. PA1b is part of the PA1 gene which, after post-translational modifications, encodes two peptides (PA1b and PA1a). We show that transforming tobacco with the PA1b cDNA alone does not result in production of the toxin and, in fact, the entire cDNA is necessary, raising the question of the role of PA1a. We constructed a PA1-cassette, allowing for the quick "cut/paste" of different PA1b mutants within a conserved PA1 cDNA. This cassette enabled us to produce the six isoforms of PA1b which exist in pea seeds. Biological tests revealed that all the isoforms display similar activity, with the exception of one which is inactive. The lack of activity in this isoform led us to conclude that the amphiphilic nature of the peptide is necessary for activity. The possible applications of this expression system for other cysteine-rich biomolecules are discussed.

  15. Psychological Correlates of Self-Reported and Objectively Measured Physical Activity among Chinese Children—Psychological Correlates of PA

    PubMed Central

    Wang, Jing-Jing; Baranowski, Tom; Lau, Patrick W. C.; Chen, Tzu-An; Zhang, Shu-Ge

    2016-01-01

    This study aimed to explore the associations among psychological correlates and physical activity (PA) in Chinese children and to further examine whether these associations varied by different PA measures. PA self-efficacy, motivation, and preference were reported in 449 8–13-year-old Chinese children (252 males). Moderate- to vigorous- intensity PA (MVPA) was measured by the Physical Activity Questionnaire for Older Children (PAQ-C) and with an ActiGraph GT3X accelerometer. Correlations and hierarchical regressions were performed to explore their associations. The study psychological variables were all positively related to PAQ-C and objective MVPA (r: 0.22–0.63). The associations with PAQ-C were all substantially stronger than those with accelerometry. Beyond the explained variance accounted for by demographics and social desirability, the addition of the psychological correlates accounted for 45% of the variance of the PAQ-C score, while only 13% for accelerometry-based MVPA. The associations of specific variables with the PAQ-C score (age, PA self-efficacy, autonomous motivation and preference) were somewhat different from those associated with objective MVPA (PA self-efficacy, autonomous motivation, and negatively associated with female gender). This study demonstrated the importance of self-efficacy and autonomous motivation in association with PA and indicated the difference in level of their associations with different PA measures. PMID:27754396

  16. Induction of primary cutaneous melanocytic neoplasms in urokinase-type plasminogen activator (uPA)-deficient and wild-type mice: cellular blue nevi invade but do not progress to malignant melanoma in uPA-deficient animals.

    PubMed

    Shapiro, R L; Duquette, J G; Roses, D F; Nunes, I; Harris, M N; Kamino, H; Wilson, E L; Rifkin, D B

    1996-08-01

    Evidence suggests that the plasminogen activators (PAs), in particular urokinase-type PA (uPA), play a pivotal role in tumor invasion and metastasis. We studied the contribution of the PAs to the malignant phenotype through the chemical induction of melanocytic neoplasms in uPA-deficient mice. Primary tumors were induced and promoted concurrently in 35 uPA-/- deficient and 35 uPA+/+ wild-type mice using a single application of 7,12-dimethylbenz(a)anthracene followed by repetitive applications of croton oil. Animals were sacrificed at 60-day intervals for 1 year. At necropsy, the four largest pigmented lesions in each animal were excised, characterized histologically, and evaluated microscopically for evidence of invasion. The regional lymph nodes, lungs, and solid abdominal visceral organs were sectioned and examined microscopically for evidence of metastatic disease. Cellular blue nevi were induced in 100% of uPA-/- and uPA+/+ promoted animals. Although a reduction in the radial and vertical progression of these lesions was noted in the uPA-deficient mice compared with the wild-type group, more than 95% of cellular blue nevi induced in both groups of animals invaded the underlying tissues. These lesions did not metastasize to the regional lymph nodes. Malignant melanoma arose in 5 of 35 (14.3%) of promoted wild-type mice. These tumors were locally aggressive, produced tissue-type PA, but were not metastatic to the regional nodes, lungs, or abdominal viscera. These results indicate that the invasive capability of melanocytic lesions may depend more on tissue-type PA than uPA activity. No melanomas were induced in the uPA-/- mice. The resistance of the uPA -/- strain to melanoma induction suggests that uPA contributes to malignant progression. We propose that the absence of uPA negatively affects tumorigenesis by decreasing the liberation and availability of growth factors such as basic fibroblast growth factor.

  17. Sexual activity patterns in rams.

    PubMed Central

    Bernon, D E; Shrestha, J N

    1984-01-01

    Behaviour was measured in reproductively experienced rams from three crossbred strains and two pure breeds (Suffolk and Finnish Landrace) in an attempt to develop a method for rapid screening of sexually aggressive rams and to measure breed differences in sexual activity. A set sequential pattern of activity need not occur in sexually experienced rams, and components of their sexual behaviour may be influenced by the estrual status of the ewe. The data indicate that the number of attempted mounts is an acceptable selection tool, with a mount following a short period of investigation most likely to be followed by coitus. Two sequential ten minute periods are sufficient for rapid screening of rams for short-term sexual activity levels. PMID:6713255

  18. Spatial arrangement and functional role of α subunits of proteasome activator PA28 in hetero-oligomeric form

    SciTech Connect

    Sugiyama, Masaaki; Sahashi, Hiroki; Kurimoto, Eiji; Takata, Shin-ichi; Yagi, Hirokazu; Kanai, Keita; Sakata, Eri; Minami, Yasufumi; Tanaka, Keiji; Kato, Koichi

    2013-03-01

    Highlights: ► Homologous α and β subunits are alternatively arranged in the PA28 heptameric ring. ► The flexible loops of the three α subunits surround the site of substrate entry. ► The loops serve as gatekeepers that selectively hinder passage of longer peptides. - Abstract: A major form of proteasome activator PA28 is a heteroheptamer composed of interferon-γ-inducible α and β subunits, which share approximately 50% amino acid identity and possess distinct insert loops. This activator forms a complex with the 20S proteasome and thereby stimulates proteasomal degradation of peptides in an ATP-independent manner, giving rise to smaller antigenic peptides presented by major histocompatibility complex class I molecules. In this study, we performed biophysical and biochemical characterization of the structure and function of the PA28 hetero-oligomer. Deuteration-assisted small-angle neutron scattering demonstrated three α and four β subunits are alternately arranged in the heptameric ring. In this arrangement, PA28 loops surround the central pore of the heptameric ring (site for peptide entry). Activating the 20S proteasome with a PA28 mutant that lacked the α subunit loops cleaved model substrates longer than a nonapeptide with better efficiency when compared to wild-type PA28. Based on these data, we hypothesize that the flexible PA28 loops act as gatekeepers, which function to select the length of peptide substrates to be transported between the proteolytic chamber and the extra-proteasomal medium.

  19. Scale up and pharmacokinetic study of a novel mutated chimeric tissue plasminogen activator (mt-PA) in rats

    PubMed Central

    Raigani, Mozhgan; Rouini, Mohammad-Reza; Golabchifar, Ali-Akbar; Mirabzadeh, Esmat; Vaziri, Behrouz; Barkhordari, Farzaneh; Davami, Fatemeh; Mahboudi, Fereidoun

    2017-01-01

    Because of high mortality caused by cardiovascular diseases, various fibrinolytic agents with diverse pharmacokinetic and pharmacodynamic properties have been developed. A novel mutated chimeric tissue plasminogen activator (mt-PA) was developed by the removal of first three domains of t-PA, insertion of GHRP sequence and mutation towards resistance to plasminogen activator inhibitor-1 (PAI-1). Mt-PA protein was expressed in Expi293F cells. The expression level of mt-PA was found to be 5000 IU/mL. Following purification, the pharmacokinetic properties of mt-PA were evaluated in three doses in rats. Data related to mt-PA were best fitted to two compartment model. With the increase in dose, the Area Under the plasma concentration-time Curve (AUC0→∞) increased. The elimination half-life (t1/2) of mt-PA was in the range of 19.1–26.1 min in three doses while that of Alteplase was 8.3 min. The plasma clearance (CLp) of mt-PA ranged from 3.8 to 5.9 mL/min in three doses, which was several times lower than that of Alteplase (142.6 mL/min). The mean residence time (MRT) of mt-PA ranged from 23.3–31.8 min in three doses, which was 4–5 times greater than that of Alteplase (6 min). Mt-PA showed extended half-life and mean residence time and is a good candidate for further clinical studies. PMID:28223717

  20. Multifunctional roles of urokinase plasminogen activator (uPA) in cancer stemness and chemoresistance of pancreatic cancer

    PubMed Central

    Asuthkar, Swapna; Stepanova, Victoria; Lebedeva, Tatiana; Holterman, AiXuan L.; Estes, Norman; Cines, Douglas B.; Rao, Jasti S.; Gondi, Christopher S.

    2013-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is almost always lethal. One of the underlying reasons for this lethality is believed to be the presence of cancer stem cells (CSC), which impart chemoresistance and promote recurrence, but the mechanisms responsible are unclear. Recently the poor prognosis of PDAC has been correlated with increased expression of urokinase plasminogen activator (uPA). In the present study we examine the role of uPA in the generation of PDAC CSC. We observe a subset of cells identifiable as a side population (SP) when sorted by flow cytometry of MIA PaCa-2 and PANC-1 pancreatic cancer cells that possess the properties of CSC. A large fraction of these SP cells are CD44 and CD24 positive, are gemcitabine resistant, possess sphere-forming ability, and exhibit increased tumorigenicity, known characteristics of cancer stemness. Increased tumorigenicity and gemcitabine resistance decrease after suppression of uPA. We observe that uPA interacts directly with transcription factors LIM homeobox-2 (Lhx2), homeobox transcription factor A5 (HOXA5), and Hey to possibly promote cancer stemness. uPA regulates Lhx2 expression by suppressing expression of miR-124 and p53 expression by repressing its promoter by inactivating HOXA5. These results demonstrate that regulation of gene transcription by uPA contributes to cancer stemness and clinical lethality. PMID:23864708

  1. Multifunctional roles of urokinase plasminogen activator (uPA) in cancer stemness and chemoresistance of pancreatic cancer.

    PubMed

    Asuthkar, Swapna; Stepanova, Victoria; Lebedeva, Tatiana; Holterman, Aixuan L; Estes, Norman; Cines, Douglas B; Rao, Jasti S; Gondi, Christopher S

    2013-09-01

    Pancreatic ductal adenocarcinoma (PDAC) is almost always lethal. One of the underlying reasons for this lethality is believed to be the presence of cancer stem cells (CSC), which impart chemoresistance and promote recurrence, but the mechanisms responsible are unclear. Recently the poor prognosis of PDAC has been correlated with increased expression of urokinase plasminogen activator (uPA). In the present study we examine the role of uPA in the generation of PDAC CSC. We observe a subset of cells identifiable as a side population (SP) when sorted by flow cytometry of MIA PaCa-2 and PANC-1 pancreatic cancer cells that possess the properties of CSC. A large fraction of these SP cells are CD44 and CD24 positive, are gemcitabine resistant, possess sphere-forming ability, and exhibit increased tumorigenicity, known characteristics of cancer stemness. Increased tumorigenicity and gemcitabine resistance decrease after suppression of uPA. We observe that uPA interacts directly with transcription factors LIM homeobox-2 (Lhx2), homeobox transcription factor A5 (HOXA5), and Hey to possibly promote cancer stemness. uPA regulates Lhx2 expression by suppressing expression of miR-124 and p53 expression by repressing its promoter by inactivating HOXA5. These results demonstrate that regulation of gene transcription by uPA contributes to cancer stemness and clinical lethality.

  2. Recombinant tissue plasminogen activator (rtPA) for the treatment of hepatic veno-occlusive disease (VOD).

    PubMed

    Kulkarni, S; Rodriguez, M; Lafuente, A; Mateos, P; Mehta, J; Singhal, S; Saso, R; Tait, D; Treleaven, J G; Powles, R L

    1999-04-01

    Seventeen patients who developed hepatic veno-occlusive disease (VOD) following hematopoietic stem cell transplantation were treated with recombinant tissue plasminogen activator (rtPA) with or without heparin. rtPA was started a median of 13 days post transplant (range 4-35). All patients received rtPA at a dose of 10 mg/day as a starting dose, and 12 patients also received heparin (1500 U bolus; then 100 U/kg/day as a continuous i.v. infusion). The median number of days of rtPA therapy was 2.5 (1-12). The median total serum bilirubin level was 116 mmol/l (range 63-194) at the beginning of treatment. Six patients showed a response to rtPA treatment (29%). It was observed that by day 2 of rtPA therapy, bilirubin levels in responders showed a downwards trend as compared to those in nonresponders. In all except one patient this response was observed after two doses of rtPA. Seven out of the 11 non-responders had a past history of liver dysfunction, compared with none of the responders. There were no differences between the two groups in terms of day of onset of liver dysfunction, manifestations of disease, maximum bilirubin and creatinine levels, and day of commencing treatment. No patient experienced severe hemorrhagic complications during therapy. Four responders survived for more than 100 days compared to none of the non-responders. Probability of survival was 33% at day 100. It is difficult to unequivocally establish the role of rtPA in the treatment of VOD. The importance of bilirubin levels on days 2 or 3 of therapy in predicting outcome should be established, as should the optimum dose of rtPA and optimum duration of therapy.

  3. Geochemical data package for the Hanford immobilized low-activity tank waste performance assessment (ILAW PA)

    SciTech Connect

    DI Kaplan; RJ Serne

    2000-02-24

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are stored in single- and double-shell tanks at the Hanford Site. The preferred method of disposing of the portion that is classified as low-activity waste is to vitrify the liquid/slurry and place the solid product in near-surface, shallow-land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford Immobilized Low-Activity Tank Waste (ILAW) Performance Assessment (PA) activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities, and the consequent transport of dissolved contaminants in the porewater of the vadose zone. Pacific Northwest National Laboratory assists LMHC in their performance assessment activities. One of the PNNL tasks is to provide estimates of the geochemical properties of the materials comprising the disposal facility, the disturbed region around the facility, and the physically undisturbed sediments below the facility (including the vadose zone sediments and the aquifer sediments in the upper unconfined aquifer). The geochemical properties are expressed as parameters that quantify the adsorption of contaminants and the solubility constraints that might apply for those contaminants that may exceed solubility constraints. The common parameters used to quantify adsorption and solubility are the distribution coefficient (K{sub d}) and the thermodynamic solubility product (K{sub sp}), respectively. In this data package, the authors approximate the solubility of contaminants using a more simplified construct

  4. The proteasome activator 11 S REG (PA28) and class I antigen presentation.

    PubMed Central

    Rechsteiner, M; Realini, C; Ustrell, V

    2000-01-01

    There are two immune responses in vertebrates: humoral immunity is mediated by circulating antibodies, whereas cytotoxic T lymphocytes (CTL) confer cellular immunity. CTL lyse infected cells upon recognition of cell-surface MHC Class I molecules complexed with foreign peptides. The displayed peptides are produced in the cytosol by degradation of host proteins or proteins from intracellular pathogens that might be present. Proteasomes are cylindrical multisubunit proteases that generate many of the peptides eventually transferred to the cell surface for immune surveillance. In mammalian proteasomes, six active sites face a central chamber. As this chamber is sealed off from the enzyme's surface, there must be mechanisms to promote entry of substrates. Two protein complexes have been found to bind the ends of the proteasome and activate it. One of the activators is the 19 S regulatory complex of the 26 S proteasome; the other activator is '11 S REG' [Dubiel, Pratt, Ferrell and Rechsteiner (1992) J. Biol. Chem. 267, 22369-22377] or 'PA28' [Ma, Slaughter and DeMartino (1992) J. Biol. Chem. 267, 10515-10523]. During the past 7 years, our understanding of the structure of REG molecules has increased significantly, but much less is known about their biological functions. There are three REG subunits, namely alpha, beta and gamma. Recombinant REGalpha forms a ring-shaped heptamer of known crystal structure. 11 S REG is a heteroheptamer of alpha and beta subunits. REGgamma is also presumably a heptameric ring, and it is found in the nuclei of the nematode work Caenorhabditis elegans and higher organisms, where it may couple proteasomes to other nuclear components. REGalpha and REGbeta, which are abundant in vertebrate immune tissues, are located mostly in the cytoplasm. Synthesis of REG alpha and beta subunits is induced by interferon-gamma, and this has led to the prevalent hypothesis that REG alpha/beta hetero-oligomers play an important role in Class I antigen

  5. pA2 values for antagonists of platelet activating factor on aggregation of rabbit platelets.

    PubMed Central

    O'Donnell, S. R.; Barnett, C. J.

    1988-01-01

    1. The relative potencies, and equilibrium dissociation constants, for nine antagonists of platelet activating factor (Paf) have been determined on rabbit platelets (in diluted platelet-rich plasma (PRP)) in experiments in which the aggregatory response to Paf was measured. 2. Log concentration-response (% maximum) curves to Paf were obtained in the absence (controls) and presence of different concentrations of each Paf antagonist drug. The antagonists shifted the Paf curves to a higher concentration range and the slopes of the Schild plots, constructed from these data, suggested that the drugs were competitive antagonists of Paf. The slopes of the Schild plots for CV-3988 and SRI 63-119 were greater than 1. 3. The pA2 values (pKB values in parentheses) were: WEB 2086 7.31 (7.63); SRI 63-119 6.95; L-652,731 6.71 (6.73); BN 52021 6.38 (6.47); SRI 63-072 6.36 (6.43); CV-3988 5.87; 48740 RP 4.97 (5.07); ketotifen 4.94 (4.95); thiazinamium 4.73 (4.76). 4. This study provides, for the first time, some functional response data for Paf antagonists (pKB values) which are in an appropriate form for use in classifying putative Paf receptors. The study also provides the comparative potencies of these Paf antagonists in inhibiting Paf-induced platelet aggregation. WEB 2086 was the most potent of the drugs examined. PMID:3293683

  6. Improved Antimicrobial Activities of Synthetic-Hybrid Bacteriocins Designed from Enterocin E50-52 and Pediocin PA-1

    PubMed Central

    Tiwari, Santosh Kumar; Sutyak Noll, Katia; Cavera, Veronica L.

    2014-01-01

    Two hybrid bacteriocins, enterocin E50-52/pediocin PA-1 (EP) and pediocin PA-1/enterocin E50-52 (PE), were designed by combining the N terminus of enterocin E50-52 and the C terminus of pediocin PA-1 and by combining the C terminus of pediocin PA-1 and the N terminus of enterocin E50-52, respectively. Both hybrid bacteriocins showed reduced MICs compared to those of their natural counterparts. The MICs of hybrid PE and EP were 64- and 32-fold lower, respectively, than the MIC of pediocin PA-1 and 8- and 4-fold lower, respectively, than the MIC of enterocin E50-52. In this study, the effect of hybrid as well as wild-type (WT) bacteriocins on the transmembrane electrical potential (ΔΨ) and their ability to induce the efflux of intracellular ATP were investigated. Enterocin E50-52, pediocin PA-1, and hybrid bacteriocin PE were able to dissipate ΔΨ, but EP was unable to deplete this component. Both hybrid bacteriocins caused a loss of the intracellular concentration of ATP. EP, however, caused a faster efflux than PE and enterocin E50-52. Enterocin E50-52 and hybrids PE and EP were active against the Gram-positive and Gram-negative bacteria tested, such as Micrococcus luteus, Salmonella enterica serovar Enteritidis 20E1090, and Escherichia coli O157:H7. The hybrid bacteriocins designed and described herein are antimicrobial peptides with MICs lower those of their natural counterparts. Both hybrid peptides induce the loss of intracellular ATP and are capable of inhibiting Gram-negative bacteria, and PE dissipates the electrical potential. In this study, the MIC of hybrid bacteriocin PE decreased 64-fold compared to the MIC of its natural peptide counterpart, pediocin PA-1. Inhibition of Gram-negative pathogens confers an additional advantage for the application of these peptides in therapeutics. PMID:25527560

  7. Improved antimicrobial activities of synthetic-hybrid bacteriocins designed from enterocin E50-52 and pediocin PA-1.

    PubMed

    Tiwari, Santosh Kumar; Sutyak Noll, Katia; Cavera, Veronica L; Chikindas, Michael L

    2015-03-01

    Two hybrid bacteriocins, enterocin E50-52/pediocin PA-1 (EP) and pediocin PA-1/enterocin E50-52 (PE), were designed by combining the N terminus of enterocin E50-52 and the C terminus of pediocin PA-1 and by combining the C terminus of pediocin PA-1 and the N terminus of enterocin E50-52, respectively. Both hybrid bacteriocins showed reduced MICs compared to those of their natural counterparts. The MICs of hybrid PE and EP were 64- and 32-fold lower, respectively, than the MIC of pediocin PA-1 and 8- and 4-fold lower, respectively, than the MIC of enterocin E50-52. In this study, the effect of hybrid as well as wild-type (WT) bacteriocins on the transmembrane electrical potential (ΔΨ) and their ability to induce the efflux of intracellular ATP were investigated. Enterocin E50-52, pediocin PA-1, and hybrid bacteriocin PE were able to dissipate ΔΨ, but EP was unable to deplete this component. Both hybrid bacteriocins caused a loss of the intracellular concentration of ATP. EP, however, caused a faster efflux than PE and enterocin E50-52. Enterocin E50-52 and hybrids PE and EP were active against the Gram-positive and Gram-negative bacteria tested, such as Micrococcus luteus, Salmonella enterica serovar Enteritidis 20E1090, and Escherichia coli O157:H7. The hybrid bacteriocins designed and described herein are antimicrobial peptides with MICs lower those of their natural counterparts. Both hybrid peptides induce the loss of intracellular ATP and are capable of inhibiting Gram-negative bacteria, and PE dissipates the electrical potential. In this study, the MIC of hybrid bacteriocin PE decreased 64-fold compared to the MIC of its natural peptide counterpart, pediocin PA-1. Inhibition of Gram-negative pathogens confers an additional advantage for the application of these peptides in therapeutics.

  8. 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

  9. 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…

  10. Patterns of Walkability, Transit, and Recreation Environment for Physical Activity

    PubMed Central

    Adams, Marc A.; Todd, Michael; Kurka, Jonathan; Conway, Terry L.; Cain, Kelli L.; Frank, Lawrence D.; Sallis, James F.

    2015-01-01

    Introduction Diverse combinations of built environment (BE) features for physical activity (PA) are understudied. This study explored whether patterns of GIS-derived BE features explained objective and self-reported PA, sedentary behavior, and BMI. Methods Neighborhood Quality of Life Study participants (N=2,199, aged 20–65 years, 48.2% female, 26% ethnic minority) were sampled in 2001–2005 from Seattle/King County, WA and Baltimore, MD/Washington, DC regions. Their addresses were geocoded to compute net residential density, land use mix, retail floor area ratio, intersection density, public transit, and public park and private recreation facility densities using a 1-km network buffer. Latent profile analyses (LPAs) were estimated from these variables. Multilevel regression models compared profiles on accelerometer-measured moderate to vigorous PA (MVPA) and self-reported PA, adjusting for covariates and clustering. Analyses were conducted in 2013–2014. Results Seattle region LPAs yielded four profiles, including low walkable/transit/recreation (L-L-L), mean walkability/transit/recreation (M-M-M), moderately high walkability/transit/recreation (MH-MH-MH), and high walkability/transit/recreation (H-H-H). All measures were higher in the H-H-H than the L-L-L profile (difference of 17.1 minutes/day for MVPA, 146.5 minutes/week for walking for transportation, 58.2 minutes/week for leisure-time PA, and 2.2 BMI points; all p<0.05). Baltimore region LPAs yielded four profiles, including L-L-L, M-M-M, high land use mix, transit, and recreation (HLU-HT-HRA), and high intersection density, high retail floor area ratio (HID-HRFAR). HLU-HT-HRA and L-L-L differed by 12.3 MVPA minutes/day; HID-HRFAR and L-L-L differed by 157.4 minutes/week for walking for transportation (all p<0.05). Conclusions Patterns of environmental features explain greater differences in adults’ PA than the four-component walkability index. PMID:26232902

  11. 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

  12. 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.

  13. Two-photon activation and excitation properties of PA-GFP in the 720-920-nm region.

    PubMed

    Schneider, Marc; Barozzi, Sara; Testa, Ilaria; Faretta, Mario; Diaspro, Alberto

    2005-08-01

    This report covers the two-photon activation and excitation properties of the PA-GFP, a photoactivatable variant of the Aequorea victoria green fluorescent protein in the spectral region from 720 to 920 nm. It is known from this special form of the molecule that it has an increased level of fluorescence emission when excited at 488 nm after irradiation at lambda approximately 413 nm, under single-photon excitation conditions. Here, we show that upon two-photon irradiation, PA-GFP yields activation in the spectral region from 720 to 840 nm. After photoactivation, the excitation spectrum shifts maintaining the very same emission spectrum of the single-photon case for the native and photoactivated protein. Additionally, when comparing the conventional photoactivation at lambda = 405 nm with a two-photon one, a sharper and better controllable three-dimensional volume of activation is obtained.

  14. PACAP Interacts with PAC1 Receptors to Induce Tissue Plasminogen Activator (tPA) Expression and Activity in Schwann Cell-Like Cultures

    PubMed Central

    Castorina, Alessandro; Waschek, James A.; Marzagalli, Rubina; Cardile, Venera; Drago, Filippo

    2015-01-01

    Regeneration of peripheral nerves depends on the abilities of rejuvenating axons to migrate at the injury site through cellular debris and altered extracellular matrix, and then grow along the residual distal nerve sheath conduit and reinnervate synaptic targets. Considerable evidence suggest that glial cells participate in this process, although the mechanisms remain to be clarified. In cell culture, regenerating neurites secrete PACAP, a peptide shown to induce the expression of the protease tissue plasminogen activator (tPA) in neural cell types. In the present studies, we tested the hypothesis that PACAP can stimulate peripheral glial cells to produce tPA. More specifically, we addressed whether or not PACAP promoted the expression and activity of tPA in the Schwann cell line RT4-D6P2T, which shares biochemical and physical properties with Schwann cells. We found that PACAP dose- and time-dependently stimulated tPA expression both at the mRNA and protein level. Such effect was mimicked by maxadilan, a potent PAC1 receptor agonist, but not by the PACAP-related homolog VIP, suggesting a PAC1-mediated function. These actions appeared to be mediated at least in part by the Akt/CREB signaling cascade because wortmannin, a PI3K inhibitor, prevented peptide-driven CREB phosphorylation and tPA increase. Interestingly, treatment with BDNF mimicked PACAP actions on tPA, but acted through both the Akt and MAPK signaling pathways, while causing a robust increase in PACAP and PAC1 expression. PACAP6-38 totally blocked PACAP-driven tPA expression and in part hampered BDNF-mediated effects. We conclude that PACAP, acting through PAC1 receptors, stimulates tPA expression and activity in a Akt/CREB-dependent manner to promote proteolytic activity in Schwann-cell like cultures. PMID:25658447

  15. 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.

  16. Murine monoclonal antibodies against murine uPA receptor produced in gene-deficient mice: inhibitory effects on receptor-mediated uPA activity in vitro and in vivo.

    PubMed

    Pass, Jesper; Jögi, Annika; Lund, Ida K; Rønø, Birgitte; Rasch, Morten G; Gårdsvoll, Henrik; Lund, Leif R; Ploug, Michael; Rømer, John; Danø, Keld; Høyer-Hansen, Gunilla

    2007-06-01

    Binding of urokinase plasminogen activator (uPA) to its cellular receptor, uPAR, potentiates plasminogen activation and localizes it to the cell surface. Focal plasminogen activation is involved in both normal and pathological tissue remodeling processes including cancer invasion. The interaction between uPA and uPAR therefore represents a potential target for anti-invasive cancer therapy. Inhibitors of the human uPA-uPAR interaction have no effect in the murine system. To enable in-vivo studies in murine cancer models we have now generated murine monoclonal antibodies (mAbs) against murine uPAR (muPAR) by immunizing uPAR-deficient mice with recombinant muPAR and screened for antibodies, which inhibit the muPA-muPAR interaction. Two of the twelve mAbs obtained, mR1 and mR2, interfered with the interaction between muPAR and the amino-terminal fragment of muPA (mATF) when analyzed by surface plasmon resonance. The epitope for mR1 is located on domain I of muPAR, while that of mR2 is on domains (II-III). In cell binding experiments using radiolabelled mATF, the maximal inhibition obtained with mR1 was 85% while that obtained with mR2 was 50%. The IC(50) value for mR1 was 0.67 nM compared to 0.14 nM for mATF. In an assay based on modified anthrax toxins, requiring cell-bound muPA activity for its cytotoxity, an approximately 50% rescue of the cells could be obtained by addition of mR1. Importantly, in-vivo efficacy of mR1 was demonstrated by the ability of mR1 to rescue mice treated with a lethal dose of uPA-activatable anthrax toxins.

  17. 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

  18. 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.

  19. High-level expression of a novel recombinant human plasminogen activator (rhPA) in the milk of transgenic rabbits and its thrombolytic bioactivity in vitro.

    PubMed

    Song, Shaozheng; Ge, Xin; Cheng, Yaobin; Lu, Rui; Zhang, Ting; Yu, Baoli; Ji, Xueqiao; Qi, Zhengqiang; Rong, Yao; Yuan, Yuguo; Cheng, Yong

    2016-08-01

    The human tissue-type plasminogen activator (tPA) is a key kinase of fibrinolysis that plays an important role in dissolving fibrin clots to promote thrombolysis. The recombinant human plasminogen activator (rhPA) has more thrombolytic advantages than the wild type tPA. To increase the half-life and thrombolytic activity of tPA, a mutant containing only the essential K2 fibrin-binding and P activating plasminogen domains of the wild type tPA was cloned. This fragment was then inserted into goat β-casein regulatory sequences. Then, a mammary gland-specific expression vector, PCL25/rhPA, was constructed, and the transgenic rabbits were generated. In this study, 18 live transgenic founders (12♀, 6♂) were generated using pronuclear microinjection. Six transgenic rabbits were obtained, and the expression levels of rhPA in the milk had a range of 15.2-630 µg/ml. A fibrin agarose plate assay of rhPA showed that it had strong thrombolytic bioactivity in vitro, and the highest specific activity was >360 (360 times more than that of alteplase). The results indicated that the rhPA containing only the K2 and P domains is efficiently expressed with higher thrombolytic bioactivity in the milk of transgenic rabbits. Our study also demonstrated a new method for the large-scale production of clinically relevant recombinant pharmaceutical proteins in the mammary glands of transgenic rabbits.

  20. Static or dynamic predictors of physical activity (PA)? A tracking study based on 12- and 38-month follow-ups in older adults.

    PubMed

    de Souto Barreto, Philipe; Ferrandez, Anne-Marie

    2014-01-01

    Studies that investigated stability of PA in older populations are scarce. Moreover, no studies used dynamic indicators to predict PA trajectories. The purpose of the present study were to investigate PA stability overtime, and to examine if changes in self-reported physical function (dynamic indicator) are better predictors of trajectories of PA than baseline measures of physical function (static indicator). This is a prospective postal survey with two time-point follow-ups: 12 and 38 months. Participants were older adults aged ≥ 60 years, and members of the medical insurance scheme of the French national education system. They responded to a self-report questionnaire on PA and general health status at three different times: baseline, 12- and 38-month follow-ups (n=243 for the 12-month follow-up; n=164 for the 38-month follow-up). Overtime analyses of PA showed a moderate-to-good stability with regard to both duration and volume of PA; however, a decrease in stability for vigorous PA was found between 12- and 38-month follow-ups. Both baseline measure and changes in physical function predicted PA trajectories, but magnitudes of associations were stronger for the dynamic indicator. Moreover, change in physical function was the only predictor of both becoming active compared with Inactive (reduced probability) and becoming inactive compared to Active (increased probability). In conclusion, a dynamic indicator of physical function is a better predictor of PA variation than static indicators.

  1. Functional Characterization of Phalaenopsis aphrodite Flowering Genes PaFT1 and PaFD.

    PubMed

    Jang, Seonghoe; Choi, Sang-Chul; Li, Hsing-Yi; An, Gynheung; Schmelzer, Elmon

    2015-01-01

    We show that the key flowering regulators encoded by Phalaenopsis aphrodite FLOWERING LOCUS T1 (PaFT1) and PaFD share high sequence homologies to these from long-day flowering Arabidopsis and short-day flowering rice. Interestingly, PaFT1 is specifically up-regulated during flowering inductive cooling treatment but is not subjected to control by photoperiod in P. aphrodite. Phloem or shoot apex-specific expression of PaFT1 restores the late flowering of Arabidopsis ft mutants. Moreover, PaFT1 can suppress the delayed flowering caused by SHORT VEGATATIVE PHASE (SVP) overexpression as well as an active FRIGIDA (FRI) allele, indicating the functional conservation of flowering regulatory circuit in different plant species. PaFT1 promoter:GUS in Arabidopsis showed similar staining pattern to that of Arabidopsis FT in the leaves and guard cells but different in the shoot apex. A genomic clone or heat shock-inducible expression of PaFT1 is sufficient to the partial complementation of the ft mutants. Remarkably, ectopic PaFT1 expression also triggers precocious heading in rice. To further demonstrate the functional conservation of the flowering regulators, we show that PaFD, a bZIP transcription factor involved in flowering promotion, interacts with PaFT1, and PaFD partially complemented Arabidopsis fd mutants. Transgenic rice expressing PaFD also flowered early with increased expression of rice homologues of APETALA1 (AP1). Consistently, PaFT1 knock-down Phalaenopsis plants generated by virus-induced gene silencing exhibit delayed spiking. These studies suggest functional conservation of FT and FD genes, which may have evolved and integrated into distinct regulatory circuits in monopodial orchids, Arabidopsis and rice that promote flowering under their own inductive conditions.

  2. Functional Characterization of Phalaenopsis aphrodite Flowering Genes PaFT1 and PaFD

    PubMed Central

    Jang, Seonghoe; Choi, Sang-Chul; Li, Hsing-Yi; An, Gynheung; Schmelzer, Elmon

    2015-01-01

    We show that the key flowering regulators encoded by Phalaenopsis aphrodite FLOWERING LOCUS T1 (PaFT1) and PaFD share high sequence homologies to these from long-day flowering Arabidopsis and short-day flowering rice. Interestingly, PaFT1 is specifically up-regulated during flowering inductive cooling treatment but is not subjected to control by photoperiod in P. aphrodite. Phloem or shoot apex-specific expression of PaFT1 restores the late flowering of Arabidopsis ft mutants. Moreover, PaFT1 can suppress the delayed flowering caused by SHORT VEGATATIVE PHASE (SVP) overexpression as well as an active FRIGIDA (FRI) allele, indicating the functional conservation of flowering regulatory circuit in different plant species. PaFT1 promoter:GUS in Arabidopsis showed similar staining pattern to that of Arabidopsis FT in the leaves and guard cells but different in the shoot apex. A genomic clone or heat shock-inducible expression of PaFT1 is sufficient to the partial complementation of the ft mutants. Remarkably, ectopic PaFT1 expression also triggers precocious heading in rice. To further demonstrate the functional conservation of the flowering regulators, we show that PaFD, a bZIP transcription factor involved in flowering promotion, interacts with PaFT1, and PaFD partially complemented Arabidopsis fd mutants. Transgenic rice expressing PaFD also flowered early with increased expression of rice homologues of APETALA1 (AP1). Consistently, PaFT1 knock-down Phalaenopsis plants generated by virus-induced gene silencing exhibit delayed spiking. These studies suggest functional conservation of FT and FD genes, which may have evolved and integrated into distinct regulatory circuits in monopodial orchids, Arabidopsis and rice that promote flowering under their own inductive conditions. PMID:26317412

  3. Preclinical testing of the nitroimidazopyran PA-824 for activity against Mycobacterium tuberculosis in a series of in vitro and in vivo models.

    PubMed

    Lenaerts, Anne J; Gruppo, Veronica; Marietta, Karen S; Johnson, Christine M; Driscoll, Diane K; Tompkins, Nicholas M; Rose, Jerry D; Reynolds, Robert C; Orme, Ian M

    2005-06-01

    This study extends earlier reports regarding the in vitro and in vivo efficacies of the nitroimidazopyran PA-824 against Mycobacterium tuberculosis. PA-824 was tested in vitro against a broad panel of multidrug-resistant clinical isolates and was found to be highly active against all isolates (MIC<1 microg/ml). The activity of PA-824 against M. tuberculosis was also assessed grown under conditions of oxygen depletion. PA-824 showed significant activity at 2, 10, and 50 microg/ml, similar to that of metronidazole, in a dose-dependent manner. In a short-course mouse infection model, the efficacy of PA-824 at 50, 100, and 300 mg/kg of body weight formulated in methylcellulose or cyclodextrin/lecithin after nine oral treatments was compared with those of isoniazid, rifampin, and moxifloxacin. PA-824 at 100 mg/kg in cyclodextrin/lecithin was as active as moxifloxacin at 100 mg/kg and isoniazid at 25 mg/kg and was slightly more active than rifampin at 20 mg/kg. Long-term treatment with PA-824 at 100 mg/kg in cyclodextrin/lecithin reduced the bacterial load below 500 CFU in the lungs and spleen. No significant differences in activity between PA-824 and the other single drug treatments tested (isoniazid at 25 mg/kg, rifampin at 10 mg/kg, gatifloxacin at 100 mg/kg, and moxifloxacin at 100 mg/kg) could be observed. In summary, its good activity in in vivo models, as well as its activity against multidrug-resistant M. tuberculosis and against M. tuberculosis isolates in a potentially latent state, makes PA-824 an attractive drug candidate for the therapy of tuberculosis. These data indicate that there is significant potential for effective oral delivery of PA-824 for the treatment of tuberculosis.

  4. Increasing tPA Activity in Astrocytes Induced by Multipotent Mesenchymal Stromal Cells Facilitate Neurite Outgrowth after Stroke in the Mouse

    PubMed Central

    Xin, Hongqi; Li, Yi; Shen, Li Hong; Liu, Xianshuang; Wang, Xinli; Zhang, Jing; Pourabdollah-Nejad D, Siamak; Zhang, Chunling; Zhang, Li; Jiang, Hao; Zhang, Zheng Gang; Chopp, Michael

    2010-01-01

    We demonstrate that tissue plasminogen activator (tPA) and its inhibitors contribute to neurite outgrowth in the central nervous system (CNS) after treatment of stroke with multipotent mesenchymal stromal cells (MSCs). In vivo, administration of MSCs to mice subjected to middle cerebral artery occlusion (MCAo) significantly increased activation of tPA and downregulated PAI-1 levels in the ischemic boundary zone (IBZ) compared with control PBS treated mice, concurrently with increases of myelinated axons and synaptophysin. In vitro, MSCs significantly increased tPA levels and concomitantly reduced plasminogen activator inhibitor 1 (PAI-1) expression in astrocytes under normal and oxygen and glucose deprivation (OGD) conditions. ELISA analysis of conditioned medium revealed that MSCs stimulated astrocytes to secrete tPA. When primary cortical neurons were cultured in the conditioned medium from MSC co-cultured astrocytes, these neurons exhibited a significant increase in neurite outgrowth compared to conditioned medium from astrocytes alone. Blockage of tPA with a neutralizing antibody or knock-down of tPA with siRNA significantly attenuated the effect of the conditioned medium on neurite outgrowth. Addition of recombinant human tPA into cortical neuronal cultures also substantially enhanced neurite outgrowth. Collectively, these in vivo and in vitro data suggest that the MSC mediated increased activation of tPA in astrocytes promotes neurite outgrowth after stroke. PMID:20140248

  5. Protease-Activated Receptor 2 (PAR2) Is Upregulated by Acanthamoeba Plasminogen Activator (aPA) and Induces Proinflammatory Cytokine in Human Corneal Epithelial Cells

    PubMed Central

    Tripathi, Trivendra; Abdi, Mahshid; Alizadeh, Hassan

    2014-01-01

    Purpose. Acanthamoeba plasminogen activator (aPA) is a serine protease elaborated by Acanthamoeba trophozoites that facilitates the invasion of trophozoites to the host and contributes to the pathogenesis of Acanthamoeba keratitis (AK). The aim of this study was to explore if aPA stimulates proinflammatory cytokine in human corneal epithelial (HCE) cells via the protease-activated receptors (PARs) pathway. Methods. Acanthamoeba castellanii trophozoites were grown in peptone-yeast extract glucose for 7 days, and the supernatants were collected and centrifuged. The aPA was purified using the fast protein liquid chromatography system, and aPA activity was determined by zymography assays. Human corneal epithelial cells were incubated with or without aPA (100 μg/mL), PAR1 agonists (thrombin, 10 μM; TRAP-6, 10 μM), and PAR2 agonists (SLIGRL-NH2, 100 μM; AC 55541, 10 μM) for 24 and 48 hours. Inhibition of PAR1 and PAR2 involved preincubating the HCE cells for 1 hour with the antagonist of PAR1 (SCH 79797, 60 μM) and PAR2 (FSLLRY-NH2, 100 μM) with or without aPA. Human corneal epithelial cells also were preincubated with PAR1 and PAR2 antagonists and then incubated with or without PAR1 agonists (thrombin and TRAP-6) and PAR2 agonists (SLIGRL-NH2 and AC 55541). Expression of PAR1 and PAR2 was examined by quantitative RT-PCR (qRT-PCR), flow cytometry, and immunocytochemistry. Interleukin-8 expression was quantified by qRT-PCR and ELISA. Results. Human corneal epithelial cells constitutively expressed PAR1 and PAR2 mRNA. Acanthamoeba plasminogen activator and PAR2 agonists significantly upregulated PAR2 mRNA expression (1- and 2-fold, respectively) (P < 0.05). Protease-activated receptor 2 antagonist significantly inhibited aPA, and PAR2 agonists induced PAR2 mRNA expression in HCE cells (P < 0.05). Protease-activated receptor 1 agonists, but not aPA, significantly upregulated PAR1 mRNA expression, which was significantly inhibited by PAR1 antagonist in HCE cells

  6. Pyrrolnitrin and Hydrogen Cyanide Production by Pseudomonas chlororaphis Strain PA23 Exhibits Nematicidal and Repellent Activity against Caenorhabditis elegans

    PubMed Central

    Nandi, Munmun; Selin, Carrie; Brassinga, Ann Karen C.; Belmonte, Mark F.; Fernando, W. G. Dilantha; Loewen, Peter C.; de Kievit, Teresa R.

    2015-01-01

    Pseudomonas chlororaphis strain PA23 is a biocontrol agent able to suppress growth of the fungal pathogen Sclerotinia sclerotiorum. This bacterium produces an arsenal of exometabolites including pyrrolnitrin (PRN), phenazine (PHZ), hydrogen cyanide (HCN), and degradative enzymes. Production of these compounds is controlled at both the transcriptional and posttranscriptional levels by the Gac-Rsm system, RpoS, PsrA, and the Phz quorum-sensing system. Beyond pathogen-suppression, the success of a biocontrol agent is dependent upon its ability to establish itself in the environment where predation by bacterivorous organisms, including nematodes, may threaten persistence. The focus of this study was to investigate whether PA23 is able to resist grazing by Caenorhabditis elegans and to define the role played by exoproducts in the bacterial-nematode interaction. We discovered that both PRN and HCN contribute to fast- and slow-killing of C. elegans. HCN is well-established as having lethal effects on C. elegans; however, PRN has not been reported to be nematicidal. Exposure of L4 stage nematodes to purified PRN reduced nematode viability in a dose-dependent fashion and led to reduced hatching of eggs laid by gravid adults. Because bacterial metabolites can act as chemoattractants or repellents, we analyzed whether PA23 exhibited attractant or repulsive properties towards C. elegans. Both PRN and HCN were found to be potent repellents. Next we investigated whether the presence of C. elegans would elicit changes in PA23 gene activity. Co-culturing the two organisms increased expression of a number of genes associated with biocontrol, including phzA, hcnA, phzR, phzI, rpoS and gacS. Exoproduct analysis showed that PHZ and autoinducer signals were upregulated, consistent with the gene expression profiles. Collectively, these findings indicate that PA23 is able to sense the presence of C. elegans and it is able to both repel and kill the nematodes, which should facilitate

  7. Control of active nitrogen species used for PA-MBE growth of group III nitrides on Si

    NASA Astrophysics Data System (ADS)

    Ohachi, Tadashi; Yamabe, Nobuhiko; Yamamoto, Yuka; Wada, Motoi; Ariyada, Osamu

    2011-03-01

    A new spiral parallel mesh electrode (PME) is presented to control active nitrogen species in plasma-assisted molecular beam epitaxial (PA-MBE) growth of group III nitrides and their alloys. Direct flux of active nitrogen from radio frequency inductive coupled plasma (rf-ICP) discharge was able to be measured using a mesh electrode for filtering charge particles and electron emission due to the self-ionization of nitrogen atoms on a negatively biased electrode. In situ measurement of direct nitrogen atom fluxes using the spiral PME during PA-MBE growth of GaN and AlN on Si substrates is investigated. A linear rf power dependence of direct flux of active species on atoms such as nitrogen (N+N*), where N and N* were ground and excited atoms, respectively, from a rf-ICP was confirmed by the spiral PME. An indirect flux of nitrogen adsorbed (ADS) atoms (N+N*) during discharge was also monitored by the spiral PME and received influence of the wall surface of the growth chamber. ADS nitrogen atoms are able to be used for nitridation of Si surface to grow a double buffer layer (DBL) AlN/β-Si3N4/Si.

  8. Patterns of thermal constraint on ectotherm activity.

    PubMed

    Gunderson, Alex R; Leal, Manuel

    2015-05-01

    Thermal activity constraints play a major role in many aspects of ectotherm ecology, including vulnerability to climate change. Therefore, there is strong interest in developing general models of the temperature dependence of activity. Several models have been put forth (explicitly or implicitly) to describe such constraints; nonetheless, tests of the predictive abilities of these models are lacking. In addition, most models consider activity as a threshold trait instead of considering continuous changes in the vigor of activity among individuals. Using field data for a tropical lizard (Anolis cristatellus) and simulations parameterized by our observations, we determine how well various threshold and continuous-activity models match observed activity patterns. No models accurately predicted activity under all of the thermal conditions that we considered. In addition, simulations showed that the performance of threshold models decreased as temperatures increased, which is a troubling finding given the threat of global climate change. We also find that activity rates are more sensitive to temperature than are the physiological traits often used as a proxy for fitness. We present a model of thermal constraint on activity that integrates aspects of both the threshold model and the continuous-activity model, the general features of which are supported by activity data from other species. Overall, our results demonstrate that greater attention should be given to fine-scale patterns of thermal constraint on activity.

  9. 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

  10. 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;…

  11. Critical Role of the PA-X C-Terminal Domain of Influenza A Virus in Its Subcellular Localization and Shutoff Activity

    PubMed Central

    Hayashi, Tsuyoshi; Chaimayo, Chutikarn; McGuinness, James

    2016-01-01

    ABSTRACT PA-X is a recently identified influenza virus protein that is composed of the PA N-terminal 191 amino acids and unique C-terminal 41 or 61 residues. We and others showed that PA-X has a strong ability to suppress host protein synthesis via host mRNA decay, which is mediated by endonuclease activity in its N-terminal domain (B. W. Jagger, H. M. Wise, J. C. Kash, K. A. Walters, N. M. Wills, Y. L. Xiao, R. L. Dunfee, L. M. Schwartzman, A. Ozinsky, G. L. Bell, R. M. Dalton, A. Lo, S. Efstathiou, J. F. Atkins, A. E. Firth, J. K. Taubenberger, and P. Digard, 2012, Science 337:199–204, http://dx.doi.org/10.1126/science.1222213, and E. A. Desmet, K. A. Bussey, R. Stone, and T. Takimoto, 2013, J Virol 87:3108–3118, http://dx.doi.org/10.1128/JVI.02826-12). However, the mechanism of host mRNA degradation, especially where and how PA-X targets mRNAs, has not been analyzed. In this study, we determined the localization of PA-X and the role of the C-terminal unique region in shutoff activity. Quantitative subcellular localization analysis revealed that PA-X was located equally in both cytoplasm and nucleus. By characterizing a series of PA-X C-terminal deletion mutants, we found that the first 9 amino acids were sufficient for nuclear localization, but an additional 6 residues were required to induce the maximum shutoff activity observed with intact PA-X. Importantly, forced nuclear localization of the PA-X C-terminal deletion mutant enhanced shutoff activity, highlighting the ability of nuclear PA-X to degrade host mRNAs more efficiently. However, PA-X also inhibited luciferase expression from transfected mRNAs synthesized in vitro, suggesting that PA-X also degrades mRNAs in the cytoplasm. Among the basic amino acids in the PA-X C-terminal region, 3 residues, 195K, 198K, and 199R, were identified as key residues for inducing host shutoff and nuclear localization. Overall, our data indicate a critical role for the 15 residues in the PA-X C-terminal domain in

  12. Innate Visual Learning through Spontaneous Activity Patterns

    PubMed Central

    Albert, Mark V.; Schnabel, Adam; Field, David J.

    2008-01-01

    Patterns of spontaneous activity in the developing retina, LGN, and cortex are necessary for the proper development of visual cortex. With these patterns intact, the primary visual cortices of many newborn animals develop properties similar to those of the adult cortex but without the training benefit of visual experience. Previous models have demonstrated how V1 responses can be initialized through mechanisms specific to development and prior to visual experience, such as using axonal guidance cues or relying on simple, pairwise correlations on spontaneous activity with additional developmental constraints. We argue that these spontaneous patterns may be better understood as part of an “innate learning” strategy, which learns similarly on activity both before and during visual experience. With an abstraction of spontaneous activity models, we show how the visual system may be able to bootstrap an efficient code for its natural environment prior to external visual experience, and we continue the same refinement strategy upon natural experience. The patterns are generated through simple, local interactions and contain the same relevant statistical properties of retinal waves and hypothesized waves in the LGN and V1. An efficient encoding of these patterns resembles a sparse coding of natural images by producing neurons with localized, oriented, bandpass structure—the same code found in early visual cortical cells. We address the relevance of higher-order statistical properties of spontaneous activity, how this relates to a system that may adapt similarly on activity prior to and during natural experience, and how these concepts ultimately relate to an efficient coding of our natural world. PMID:18670593

  13. Physical Activity Patterns During Pregnancy in a Sample of Portuguese Women: A Longitudinal Prospective Study

    PubMed Central

    Santos, Paula Clara; Abreu, Sandra; Moreira, Carla; Santos, Rute; Ferreira, Margarida; Alves, Odete; Moreira, Pedro; Mota, Jorge

    2016-01-01

    Background Physical activity (PA) patterns during pregnancy have not been explored in depth and most previous studies lack assessment of variables such as type, frequency, duration and intensity of activity. Objectives This study had two goals: 1) to analyze PA patterns during pregnancy according to weekly time spent on different types of activity; and 2) to determine women’s perception about health care providers regarding PA advisement during pregnancy. Patients and Methods A longitudinal prospective study was carried out with a 118-pregnant women cohort. Participants were evaluated during all trimesters. Self-reported questionnaires were used to collect personal and obstetric data. Type, duration and frequency of PA were evaluated using the pregnancy physical activity questionnaire (PPAQ) and intensity levels were calculated. Repeated measure analysis of variance was performed to determine differences between trimesters, and Wilcoxon signed-rank test was performed when appropriate. Results A decrease in values of self-reported PA (MET.h.wk-1) was found from the first to the second and the first to the third trimester of pregnancy, respectively; total (270.91 vs 220.54 vs 210.35; P < 0.01), light (109.45 vs 95.11vs 92.40; P < 0.01) and moderate intensity (81.99 vs 50.69 vs 62.94; P = 0.002). Time spent on most activities remained fairly stable throughout pregnancy. Women spent most of their weekly time during the entire pregnancy on household and caregiving activities, occupational activities and leisure, except sport activities. Swimming was the most reported organized PA, reaching its highest proportion (12.7%) in the second trimester. Prenatal exercise classes were reported by 39.8% of women during the 3rd trimester. Pregnant women reported that PA was recommended by health professionals: 53.9% in the 1st trimester, 70.4% in the 2nd trimester and 56.8% in the 3rd trimester. Conclusions Self-reported PA decreased, especially from the first to the second

  14. Antiviral Activity of Bay 41-4109 on Hepatitis B Virus in Humanized Alb-uPA/SCID Mice

    PubMed Central

    Brezillon, Nicolas; Brunelle, Marie-Noëlle; Massinet, Hélène; Giang, Eric; Lamant, Céline; DaSilva, Lucie; Berissi, Sophie; Belghiti, Jacques; Hannoun, Laurent; Puerstinger, Gherard; Wimmer, Eva; Neyts, Johan; Hantz, Olivier; Soussan, Patrick; Morosan, Serban; Kremsdorf, Dina

    2011-01-01

    Current treatments for HBV chronic carriers using interferon alpha or nucleoside analogues are not effective in all patients and may induce the emergence of HBV resistant strains. Bay 41-4109, a member of the heteroaryldihydropyrimidine family, inhibits HBV replication by destabilizing capsid assembly. The aim of this study was to determine the antiviral effect of Bay 41-4109 in a mouse model with humanized liver and the spread of active HBV. Antiviral assays of Bay 41-4109 on HepG2.2.15 cells constitutively expressing HBV, displayed an IC50 of about 202 nM with no cell toxicity. Alb-uPA/SCID mice were transplanted with human hepatocytes and infected with HBV. Ten days post-infection, the mice were treated with Bay 41-4109 for five days. During the 30 days of follow-up, the HBV load was evaluated by quantitative PCR. At the end of treatment, decreased HBV viremia of about 1 log(10) copies/ml was observed. By contrast, increased HBV viremia of about 0.5 log(10) copies/ml was measured in the control group. Five days after the end of treatment, a rebound of HBV viremia occurred in the treated group. Furthermore, 15 days after treatment discontinuation, a similar expression of the viral capsid was evidenced in liver biopsies. Our findings demonstrate that Bay 41-4109 displayed antiviral properties against HBV in humanized Alb-uPA/SCID mice and confirm the usefulness of Alb-uPA/SCID mice for the evaluation of pharmaceutical compounds. The administration of Bay 41-4109 may constitute a new strategy for the treatment of patients in escape from standard antiviral therapy. PMID:22162746

  15. Cerebral activation pattern in primary writing tremor

    PubMed Central

    Berg, D; Preibisch, C; Hofmann, E; Naumann, M

    2000-01-01

    OBJECTIVE—To compare the cerebral activation pattern during writing of patients with writing tremor with healthy controls using functional MRI
METHODS—Three patients with writing tremor and 10 healthy controls were examined using a 1.5 Tesla scanner. All subjects performed a paradigm of alternating 30 second periods of rest or writing. For functional imaging 60 EPI multislice data sets were acquired. All images were analyzed using SPM96 software. Data were analyzed for the group of patients with writing tremor and compared with those of the control group.
RESULTS—Both patients with writing tremor and controls showed a significant activation of the contralateral primary sensorimotor cortex, SMA, and area 44. By contrast, motor cortex activation in writing tremor also included the contralateral premotor area (area 6) and ipsilateral prefrontal area (inferior frontal gyrus; areas 10, 44, and 47). Only patients with writing tremor showed a bilateral activation of the parietal lobule (area 40) with a more pronounced activation on the contralateral side. Furthermore, there was a bilateral activation of the cerebellum with a more pronounced area of activation on the ipsilateral side.
CONCLUSIONS—Brain areas activated in writing tremor included activation patterns otherwise typical for both essential tremor and writer's cramp. Therefore a distinct category for writing tremor integrating hallmarks of essential tremor and writer's cramp is proposed.

 PMID:11080231

  16. PA residues in the 2009 H1N1 pandemic influenza virus enhance avian influenza virus polymerase activity in mammalian cells.

    PubMed

    Bussey, Kendra A; Desmet, Emily A; Mattiacio, Jonelle L; Hamilton, Alice; Bradel-Tretheway, Birgit; Bussey, Howard E; Kim, Baek; Dewhurst, Stephen; Takimoto, Toru

    2011-07-01

    The 2009 pandemic influenza virus (pH1N1) is a swine-origin reassortant containing human, avian, and swine influenza genes. We have previously shown that the polymerase complex of the pH1N1 strain A/California/04/2009 (Cal) is highly active in mammalian 293T cells, despite the avian origin of both its PA and PB2. In this study, we analyzed the polymerase residues that are responsible for high pH1N1 polymerase activity in the mammalian host. Characterization of polymerase complexes containing various combinations of Cal and avian influenza virus A/chicken/Nanchang/3-120/01 (H3N2) (Nan) by reporter gene assay indicates that Cal PA, but not PB2, is a major contributing factor to high Cal polymerase activity in 293T cells. In particular, Cal PA significantly activates the otherwise inactive Nan polymerase at 37 and 39°C but not at the lower temperature of 34°C. Further analysis using site-directed mutagenesis showed that the Cal PA residues 85I, 186S, and 336M contribute to enhanced activity of the Cal polymerase. Recombinant A/WSN/33 (H1N1) (WSN) viruses containing Nan NP and polymerase (PA, PB1, PB2) genes with individual mutations in PA at residues 85, 186, and 336 produced higher levels of viral protein than the virus containing wild-type (WT) Nan PA. Interestingly, compared to the WT, the virus containing the 85I mutation grew faster in human A549 cells and the 336M mutation most significantly enhanced pathogenicity in a mouse model, among the three PA mutations tested. Our results suggest that multiple mutations in PA, which were rarely present in previous influenza isolates, are involved in mammalian adaptation and pathogenicity of the 2009 pH1N1.

  17. Understanding intra-neighborhood patterns in PM2.5 and PM10 using mobile monitoring in Braddock, PA

    PubMed Central

    2012-01-01

    Background Braddock, Pennsylvania is home to the Edgar Thomson Steel Works (ETSW), one of the few remaining active steel mills in the Pittsburgh region. An economically distressed area, Braddock exceeds average annual (>15 μg/m3) and daily (>35 μg/m3) National Ambient Air Quality Standards (NAAQS) for particulate matter (PM2.5). Methods A mobile air monitoring study was designed and implemented in morning and afternoon hours in the summer and winter (2010–2011) to explore the within-neighborhood spatial and temporal (within-day and between-day) variability in PM2.5 and PM10. Results Both pollutants displayed spatial variation between stops, and substantial temporal variation within and across study days. For summer morning sampling runs, site-specific mean PM2.5 ranged from 30.0 (SD = 3.3) to 55.1 (SD = 13.0) μg/m3. Mean PM10 ranged from 30.4 (SD = 2.5) to 69.7 (SD = 51.2) μg/m3, respectively. During summer months, afternoon concentrations were significantly lower than morning for both PM2.5 and PM10, potentially owing to morning subsidence inversions. Winter concentrations were lower than summer, on average, and showed lesser diurnal variation. Temperature, wind speed, and wind direction predicted significant variability in PM2.5 and PM10 in multiple linear regression models. Conclusions Data reveals significant morning versus afternoon variability and spatial variability in both PM2.5 and PM10 concentrations within Braddock. Information obtained on peak concentration periods, and the combined effects of industry, traffic, and elevation in this region informed the design of a larger stationary monitoring network. PMID:23051204

  18. Muscle Activation Patterns During Different Squat Techniques.

    PubMed

    Slater, Lindsay V; Hart, Joseph M

    2017-03-01

    Slater, LV, and Hart, JM. Muscle activation patterns during different squat techniques. J Strength Cond Res 31(3): 667-676, 2017-Bilateral squats are frequently used exercises in sport performance programs. Lower extremity muscle activation may change based on knee alignment during the performance of the exercise. The purpose of this study was to compare lower extremity muscle activation patterns during different squat techniques. Twenty-eight healthy, uninjured subjects (19 women, 9 men, 21.5 ± 3 years, 170 ± 8.4 cm, 65.7 ± 11.8 kg) volunteered. Electromyography (EMG) electrodes were placed on the vastus lateralis, vastus medialis, rectus femoris, biceps femoris, and the gastrocnemius of the dominant leg. Participants completed 5 squats while purposefully displacing the knee anteriorly (AP malaligned), 5 squats while purposefully displacing the knee medially (ML malaligned) and 5 squats with control alignment (control). Normalized EMG data (MVIC) were reduced to 100 points and represented as percentage of squat cycle with 50% representing peak knee flexion and 0 and 99% representing fully extended. Vastus lateralis, medialis, and rectus femoris activity decreased in the medio-lateral (ML) malaligned squat compared with the control squat. In the antero-posterior (AP) malaligned squat, the vastus lateralis, medialis, and rectus femoris activity decreased during initial descent and final ascent; however, vastus lateralis and rectus femoris activation increased during initial ascent compared with the control squat. The biceps femoris and gastrocnemius displayed increased activation during both malaligned squats compared with the control squat. In conclusion, participants had altered muscle activation patterns during squats with intentional frontal and sagittal malalignment as demonstrated by changes in quadriceps, biceps femoris, and gastrocnemius activation during the squat cycle.

  19. Formation of Raman Scattering Wings around H alpha, H beta, and Pa alpha in Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Chang, Seok-Jun; Heo, Jeong-Eun; Di Mille, Francesco; Angeloni, Rodolfo; Palma, Tali; Lee, Hee-Won

    2015-12-01

    Powered by a supermassive black hole with an accretion disk, the spectra of active galactic nuclei (AGNs) are characterized by prominent emission lines including Balmer lines. The unification schemes of AGNs require the existence of a thick molecular torus that may hide the broad emission line region from the view of observers near the equatorial direction. In this configuration, one may expect that the far-UV radiation from the central engine can be Raman scattered by neutral hydrogen to reappear around Balmer and Paschen emission lines, which can be identified with broad wings. We produce Hα, Hβ, and Paα wings using a Monte Carlo technique to investigate their properties. The neutral scattering region is assumed to be a cylindrical torus specified by the inner and outer radii and the height. While the covering factor of the scattering region affects the overall strengths of the wings, the wing widths are primarily dependent on the neutral hydrogen column density {N}{{H} {{I}}} being roughly proportional to {N}{{H} {{I}}}1/2. In particular, with {N}{{H} {{I}}}={10}23 {{cm}}-2 the Hα wings typically show a width ∼ 2× {10}4 {km} {{{s}}}-1. We also find that Hα and Paα wing profiles are asymmetric with the red part stronger than the blue part and an opposite behavior is seen for Hβ wings.

  20. 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.

  1. Patterns of helicity in solar active regions

    NASA Technical Reports Server (NTRS)

    Pevtsov, Alexei A.; Canfield, Richard C.; Metcalf, Thomas R.

    1994-01-01

    Using 46 vector magnetograms from the Stokes Polarimeter of Mees Solar Observatory (MSO), we studied patterns of local helicity in three diverse solar active regions. From these magnetograms we computed maps of the local helicity parameter alpha = J(sub z)/B(sub z). Although such maps are noisy, we found patterns at the level approximately 2 to 3 sigma(sub J(sub z)), which repeat in successive magnetograms for up to several days. Typically, the alpha maps of any given active region contain identifiable patches with both positive and negative values of alpha. Even within a single sunspot complex, several such alpha patches can often be seen. We followed 68 alpha patches that could be identified on at least two successive alpha maps. We found that the persistence fraction of such patches decrease exponentially, with a characteristic time approximately 27 hr.

  2. Spreading dynamics following bursty human activity patterns

    NASA Astrophysics Data System (ADS)

    Min, Byungjoon; Goh, K.-I.; Vazquez, Alexei

    2011-03-01

    We study the susceptible-infected model with power-law waiting time distributions P(τ)~τ-α, as a model of spreading dynamics under heterogeneous human activity patterns. We found that the average number of new infections n(t) at time t decays as a power law in the long-time limit, n(t)~t-β, leading to extremely slow prevalence decay. We also found that the exponent in the spreading dynamics β is related to that in the waiting time distribution α in a way depending on the interactions between agents but insensitive to the network topology. These observations are well supported by both the theoretical predictions and the long prevalence decay time in real social spreading phenomena. Our results unify individual activity patterns with macroscopic collective dynamics at the network level.

  3. Urinary-type plasminogen activator (uPA) and its receptor (uPAR) in squamous cell carcinoma of the oral cavity.

    PubMed

    Shi, Zonggao; Stack, M Sharon

    2007-10-15

    OSCC (oral squamous cell carcinoma) is the most common oral malignancy and is estimated to affect approx. 350000 new patients worldwide this year. OSCC is characterized by a high degree of morbidity and mortality, as most patients exhibit local, regional and distant metastasis at the time of diagnosis. Recent genome-wide screening efforts have identified the serine proteinase uPA (urinary-type plasminogen activator, also known as urokinase) as a strong biomarker for prediction of poor disease outcome and a key candidate for molecular classification of oral neoplasms using a 'gene signature' approach. The proteinase uPA binds a surface-anchored receptor designated uPAR (uPA receptor), focalizing proteolytic activity to the pericellular milieu. Furthermore, uPA-uPAR can interact with transmembrane proteins to modify multiple signal transduction pathways and influence a wide variety of cellular behaviours. Correlative clinical data show elevated uPA-uPAR in oral tumour tissues, with tumours exhibiting high levels of both uPA and uPAR as the most invasive. Combined in vitro, pre-clinical and clinical data support the need for further analysis of uPA-uPAR as a prognostic indicator as well as a potential therapeutic target in OSCC.

  4. Pattern Activity Clustering and Evaluation (PACE)

    NASA Astrophysics Data System (ADS)

    Blasch, Erik; Banas, Christopher; Paul, Michael; Bussjager, Becky; Seetharaman, Guna

    2012-06-01

    With the vast amount of network information available on activities of people (i.e. motions, transportation routes, and site visits) there is a need to explore the salient properties of data that detect and discriminate the behavior of individuals. Recent machine learning approaches include methods of data mining, statistical analysis, clustering, and estimation that support activity-based intelligence. We seek to explore contemporary methods in activity analysis using machine learning techniques that discover and characterize behaviors that enable grouping, anomaly detection, and adversarial intent prediction. To evaluate these methods, we describe the mathematics and potential information theory metrics to characterize behavior. A scenario is presented to demonstrate the concept and metrics that could be useful for layered sensing behavior pattern learning and analysis. We leverage work on group tracking, learning and clustering approaches; as well as utilize information theoretical metrics for classification, behavioral and event pattern recognition, and activity and entity analysis. The performance evaluation of activity analysis supports high-level information fusion of user alerts, data queries and sensor management for data extraction, relations discovery, and situation analysis of existing data.

  5. GSK-3β inhibitor TWS119 attenuates rtPA-induced hemorrhagic transformation and activates the Wnt/β-catenin signaling pathway after acute ischemic stroke in rats

    PubMed Central

    Wang, Wei; Li, Mingchang; Wang, Yuefei; Li, Qian; Deng, Gang; Wan, Jieru; Yang, Qingwu

    2016-01-01

    Hemorrhagic transformation (HT) is a devastating complication for patients with acute ischemic stroke who are treated with tissue plasminogen activator (tPA). It is associated with high morbidity and mortality, but no effective treatments are currently available to reduce HT risk. Therefore, methods to prevent HT are urgently needed. In this study, we used TWS119, an inhibitor of glycogen synthase kinase 3β (GSK-3β), to evaluate the role of the Wnt/β-catenin signaling pathway in recombinant tPA (rtPA)-induced HT. Sprague–Dawley rats were subjected to a middle cerebral artery occlusion (MCAO) model of ischemic stroke and then were administered rtPA, rtPA combined with TWS119, or vehicle at 4 h. The animals were sacrificed 24 h after infarct induction. Rats treated with rtPA showed evident HT, had more severe neurologic deficit, brain edema, and blood–brain barrier breakdown, and had larger infarction volume than did the vehicle group. Rats treated with TWS119 had significantly improved outcomes compared with those of rats treated with rtPA alone. In addition, Western blot analysis showed that TWS119 increased the protein expression of β-catenin, claudin-3, and ZO-1 while suppressing the expression of GSK-3β. These results suggest that TWS119 reduces rtPA-induced HT and attenuates blood–brain barrier disruption, possibly through activation of the Wnt/β-catenin signaling pathway. This study provides a potential therapeutic strategy to prevent tPA-induced HT after acute ischemic stroke. PMID:26671619

  6. 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.

  7. 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

  8. Thinking Patterns, Brain Activity and Strategy Choice

    NASA Astrophysics Data System (ADS)

    Nishimura, Kazuo; Okada, Akira; Inagawa, Michiyo; Tobinaga, Yoshikazu

    2012-03-01

    In this study we analyzed the relationship between thinking patterns, behavior and associated brain activity. Subjects completed a self-report assessing whether they could voluntarily stop thinking or not, and were then divided into two groups: those with the ability to stop thinking and those without. We measured subjects' brain activity using magnetoencephalography while giving them a series of tasks intended to encourage or discourage spontaneous thinking. Our findings revealed differences between the two groups in terms of which portions of the brain were active during the two types of task. A second questionnaire confirmed a relationship between the ability to stop thinking and strategy choices in a dilemma game. We found that subjects without the ability to stop thinking had a tendency to choose cooperative behavior.

  9. 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.

  10. Production of a urokinase plasminogen activator-IgG fusion protein (uPA-IgG) in the baculovirus expression system.

    PubMed

    Kost, T A; Ignar, D M; Clay, W C; Andrews, J; Leray, J D; Overton, L; Hoffman, C R; Kilpatrick, K E; Ellis, B; Emerson, D L

    1997-04-29

    Numerous studies have demonstrated the importance of urokinase plasminogen activator (uPA) and its receptor, uPAR, in the processes of tumor progression and metastasis. Thus, the uPA/uPAR interaction may represent an important target for inhibiting metastatic disease. The baculovirus expression system was used to produce high levels of a secreted uPA-Immunoglobulin G fusion protein (uPA-IgG) which could then be used for displacing uPA from the surface of tumor cells. The recombinant uPA-IgG fusion protein was placed under the control of either the viral polyhedrin promoter or a copy of the viral basic protein promoter. Recombinant viruses were then used to infect Sf9 and BTI-Tn-5B1-4 cells. Infection of both cell types resulted in the production of secreted uPA-IgG. The molecular mass of the secreted protein as determined by SDS-PAGE was approximately 40 kDa. The highest level of secreted uPA-IgG, 444 microg/ml, was found in the culture medium of BTI-Tn-5B1-4 cells 72 h post-infection with the basic protein promoter-uPA-IgG virus. In the case of Sf9 cells, the highest level of secreted protein was 195 microg/ml. The amount of cell-associated uPA-IgG in infected BTI-Tn-5B1-4 cells was significantly less than that of infected Sf9 cells, reflecting the superior secretory capability of the BTI-Tn-5B1-4 cells. The uPA-IgG was readily purified using a combination of zinc chelate and sephacryl S-100 column chromatography. Routinely, greater than 100 mg of greater than 95% pure protein could be obtained per liter of culture medium collected at 72 h post-infection of BTI-Tn-5B1-4 cells with the basic protein promoter virus. BIAcore analysis and competition binding assays using LOX human malignant melanoma cells expressing uPAR indicated that the purified recombinant protein possessed similar ligand binding characteristics to that of human uPA.

  11. TGF-β2 promotes RPE cell invasion into a collagen gel by mediating urokinase-type plasminogen activator (uPA) expression.

    PubMed

    Sugioka, Koji; Kodama, Aya; Okada, Kiyotaka; Iwata, Mihoko; Yoshida, Koji; Kusaka, Shunji; Matsumoto, Chota; Kaji, Hiroshi; Shimomura, Yoshikazu

    2013-10-01

    Transforming growth factor-beta (TGF-β) is one of the main epithelial-mesenchymal transition (EMT)-inducing factors. In general, TGF-β-induced EMT promotes cell migration and invasion. TGF-β also acts as a potent regulator of pericellular proteolysis by regulating the expression and secretion of plasminogen activators. Urokinase-type plasminogen activator (uPA) is a serine protease that binds to its cell surface receptor (uPAR) with high affinity. uPA binding to uPAR stimulates uPAR's interaction with transmembrane proteins, such as integrins, to regulate cytoskeletal reorganization and cell migration, differentiation and proliferation. However, the influence of TGF-β and the uPA/uPAR system on EMT in retinal pigment epithelial (RPE) cells is still unclear. The purpose of this study was to determine the effect of TGF-β2, which is the predominant isoform in the retina, and the uPA/uPAR system on RPE cells. In this study, we first examined the effect of TGF-β2 and/or the inhibitor of uPA (u-PA-STOP(®)) on the proliferation of a human retinal pigment epithelial cell line (ARPE-19 cells). Treatment with TGF-β2 or u-PA-STOP(®) suppressed cell proliferation. Combination treatment of TGF-β2 and u-PA-STOP(®) enhanced cell growth suppression. Furthermore, western blot analysis, fibrin zymography and real-time reverse transcription PCR showed that that TGF-β2 induced EMT in ARPE-19 cells and that the expression of uPA and uPAR expression was up-regulated during EMT. The TGF-β inhibitor SB431542 suppressed TGF-β2-stimulated uPA expression and secretion but did not suppress uPAR expression. Furthermore, we seeded ARPE-19 cells onto Transwell chambers and allowed them to invade the collagen matrix in the presence of TGF-β2 alone or with TGF-β2 and u-PA-STOP(®). TGF-β2 treatment induced ARPE-19 cell invasion into the collagen gel. Treatment with a combination of TGF-β2 and the uPA inhibitor strongly inhibited ARPE-19 cell invasion compared with treatment with

  12. 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

  13. Coagulation alterations due to local fibrinolytic therapy with recombinant tissue-type plasminogen activator (rt-PA) in patients with peripheral arterial occlusive disease

    SciTech Connect

    Rauber, Klaus; Heidinger, Kathrin S.; Kemkes-Matthes, Bettina

    1997-05-15

    Purpose. To determine the systemic effects of local fibrinolytic therapy with low-dose recombinant tissue-type plasminogen activator (rt-PA). Methods. Ten patients received intrathrombal infusion of 20 mg rt-PA and heparin for local thrombolysis and had subsequent percutaneous transluminal angioplasty (PTA). Eight controls underwent PTA and received heparin alone. We measured t-PA, D-Dimer, and fibrinogen levels before, directly after, and 20, 40, and 60 min and 24 hr after therapy. Results. In the thrombolysis group the t-PA level peaked immediately after infusion and then declined within 1 hr. D-Dimer increased and remained elevated, whereas in the control group only t-PA levels increased, and only after 24 hr. Fibrinogen remained within the normal range in both groups. Eight of ten patients in the thrombolysis group and seven of eight with PTA had clinical improvement after the procedure. Conclusions. The increase in D-Dimer in the rt-PA group indicates a good local fibrinolytic effect. The fact that fibrinogen levels remained unchanged indicates that there is a lack of systemic fibrinogenolysis.

  14. 75 FR 43809 - Airworthiness Directives; Piper Aircraft, Inc. PA-28, PA-32, PA-34, and PA-44 Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    .... PA-28, PA-32, PA- 34, and PA-44 Series Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... Aircraft, Inc. (Piper) PA-28, PA-32, PA-34, and PA-44 series airplanes. This AD requires you to inspect the... apply to certain Piper Aircraft, Inc. (Piper) PA-28, PA-32, PA- 34, and PA-44 series airplanes....

  15. Walking Patterns in a Sample of African American, Native American, and Caucasian Women: The Cross-Cultural Activity Participation Study

    ERIC Educational Resources Information Center

    Whitt, Melicia C.; DuBose, Katrina D.; Ainsworth, Barbara E.; Tudor-Locke, Catrine

    2004-01-01

    This analysis describes walking patterns among African American, Native American, and Caucasian women from South Carolina and New Mexico. Walking was assessed using pedometer and physical activity (PA) record data based on 4 consecutive days on either three (Study Phase 1) or two (Study Phase 2) occasions. Participants walked 5,429 [plus or minus]…

  16. Biochemical, thrombolytic and pharmacokinetic properties of rt-PA P47G, K49N, a substitution variant of human tissue-type plasminogen activator.

    PubMed

    Nelles, L; Li, X K; Vanlinthout, I; De Cock, F; Lijnen, H R; Collen, D

    1992-04-02

    rt-PA P47G, K49N, a substitution variant of recombinant human tissue-type plasminogen activator (rt-PA), in which proline at position 47 and lysine at position 49 were replaced by glycine and asparagine respectively, was previously described by Ahern et al. (J Biol Chem 1990; 265:5540-5) to have an extended in vivo half-life with unaltered in vitro fibrinolytic properties. Because this variant might possess an increased in vivo thrombolytic potency, we have constructed its cDNA, expressed it in Chinese hamster ovary cells and determined its biochemical, thrombolytic and pharmacokinetic properties relative to those of home-made rt-PA and of alteplase (Actilyse). The specific fibrinolytic activities on fibrin plates were 160,000 +/- 17,000, 210,000 +/- 88,000 and 460,000 +/- 72,000 IU/mg (mean +/- SEM) for rt-PA P47G, K49N, rt-PA and alteplase, respectively, while the catalytic efficiencies for plasminogen activation (k2/Km) in the absence of fibrin were comparable (1.1 to 1.7 x 10(-3) microM-1s-1). Fibrin enhanced the rate of plasminogen activation by rt-PA P47G, K49N 100-fold and by both wild-type molecules 390-fold. Binding of the variant rt-PA to fibrin was significantly reduced, but its affinity for lysine-Sepharose was unaltered. In an in vitro clot lysis system, consisting of a radiolabeled human plasma clot submersed in plasma, 50% clot lysis in 2 h required 0.67 +/- 0.14 micrograms/ml rt-PA P47G, K49N, 0.36 +/- 0.01 micrograms/ml rt-PA and 0.17 +/- 0.01 micrograms/ml alteplase, respectively (mean +/- SEM; n = 3 or 4). At these doses residual fibrinogen levels at 2 h were in excess of 80%.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Maduramicin Rapidly Eliminates Malaria Parasites and Potentiates the Gametocytocidal Activity of the Pyrazoleamide PA21A050

    PubMed Central

    Maron, Maxim I.; Magle, Crystal T.; Czesny, Beata; Turturice, Benjamin A.; Huang, Ruili; Zheng, Wei; Vaidya, Akhil B.

    2015-01-01

    New strategies targeting Plasmodium falciparum gametocytes, the sexual-stage parasites that are responsible for malaria transmission, are needed to eradicate this disease. Most commonly used antimalarials are ineffective against P. falciparum gametocytes, allowing patients to continue to be infectious for over a week after asexual parasite clearance. A recent screen for gametocytocidal compounds demonstrated that the carboxylic polyether ionophore maduramicin is active at low nanomolar concentrations against P. falciparum sexual stages. In this study, we showed that maduramicin has an EC50 (effective concentration that inhibits the signal by 50%) of 14.8 nM against late-stage gametocytes and significantly blocks in vivo transmission in a mouse model of malaria transmission. In contrast to other reported gametocytocidal agents, maduramicin acts rapidly in vitro, eliminating gametocytes and asexual schizonts in less than 12 h without affecting uninfected red blood cells (RBCs). Ring stage parasites are cleared by 24 h. Within an hour of drug treatment, 40% of the normally crescent-shaped gametocytes round up and become spherical. The number of round gametocytes increases to >60% by 2 h, even before a change in membrane potential as monitored by MitoProbe DiIC1 (5) is detectable. Maduramicin is not preferentially taken up by gametocyte-infected RBCs compared to uninfected RBCs, suggesting that gametocytes are more sensitive to alterations in cation concentration than RBCs. Moreover, the addition of 15.6 nM maduramicin enhanced the gametocytocidal activity of the pyrazoleamide PA21A050, which is a promising new antimalarial candidate associated with an increase in intracellular Na+ concentration that is proposed to be due to inhibition of PfATP4, a putative Na+ pump. These results underscore the importance of cation homeostasis in sexual as well as asexual intraerythrocytic-stage P. falciparum parasites and the potential of targeting this pathway for drug development

  18. Overexpression of Hsp27 in a human melanoma cell line: regulation of E-cadherin, MUC18/MCAM, and plasminogen activator (PA) system

    PubMed Central

    Aldrian, Silke; Kindas-Mügge, Ingela; Trautinger, Franz; Fröhlich, Ilse; Gsur, Andrea; Herbacek, Irene; Berger, Walter; Micksche, Michael

    2003-01-01

    Hsp27 is considered a potential marker for cell differentiation in diverse tissues. Several aspects linked to the differentiation process and to the transition from high to low metastatic potential were analyzed in melanoma cells transfected with Hsp27. E-cadherin plays a central role in cell differentiation, migration, and normal development. Loss of expression or function of E-cadherin has been documented in a variety of human malignancies. We observed by fluorescence-activated cell sorter (FACS) as well as immunofluorescence (IF) analysis a pronounced expression of E-cadherin in Hsp27-transfected A375 melanoma cells compared with control melanoma cells. The expression of the adhesion molecule MUC18/MCAM correlates directly with the metastatic potential of melanoma cells. In contrast to wild-type and neotransfected melanoma cells, in Hsp27-transfected cells the expression of MUC18/MCAM could not be detected by FACS and IF analysis. The plasminogen activator (PA) system plays a central role in mediating extracellular proteolysis and also in nonproteolytic events such as cell adhesion, migration, and transmembrane signaling. Hsp27 transfectants revealed elevated messenger ribonucleic acid expression of the urokinase-type PA (uPA) and its inhibitor, PA inhibitor type 1, which might indicate a neutralization effect of the proteolytic activity of uPA. Control cells failed to express both these molecules. The influence of Hsp27 expression on uPA activity and the involvement of E-cadherin could be demonstrated by use of anti–E-cadherin–blocking antibody. Our data provide evidence for an inhibitory-regulatory role of Hsp27 in tumor progression as found in our system. PMID:14984058

  19. Weekday and weekend physical activity patterns of French and Spanish adolescents.

    PubMed

    Aibar, Alberto; Bois, Julien E; Zaragoza Casterad, Javier; Generelo, Eduardo; Paillard, Thierry; Fairclough, Stuart

    2014-01-01

    Adolescents' objectively assessed physical activity (PA) patterns during specific segments of the day remain unclear. In order to develop a clearer understanding this study examined country and gender differences in moderate to vigorous physical activity (MVPA) levels during specific segments of weekdays and weekend days, and explored the contribution of each segment to PA guidelines. Morpho-demographic, socio-economic and PA data were collected from a sample of 829 French and Spanish adolescents (45.0% Spanish; 55.2% females; 14.33±.73 years). Actigraph GT3X accelerometers were worn for seven days to assess adolescents' MVPA for three segments of weekdays (school-travel-time, school-time, and non-school-time), and weekend days (morning-time, afternoon-time and night-time). Data were analysed using multilevel modelling. The most active segments were non-school-time (29.2±17.5 min) and school-time (25.8±14.2 min) during weekdays, and morning-time (28.2±25.8 min) on weekend days. Except for school-time, Spanish adolescents were more significantly active than French adolescents during all segments. Significant gender differences were found in all segments. Country differences highlight the need to recognise cultural contexts that influence adolescents' PA. Common European-wide strategies may be insufficient to increase MVPA levels if cultural variability is not considered. Spanish and French PA intervention programmes should target girls and low-active boys during non-school-time and weekends.

  20. Patterns of weekday and weekend physical activity in youth in 2 Canadian provinces.

    PubMed

    Comte, Melisa; Hobin, Erin; Majumdar, Sumit R; Plotnikoff, Ronald C; Ball, Geoff D C; McGavock, Jonathan

    2013-02-01

    Few Canadian children are meeting physical activity (PA) guidelines for optimal growth and health. There is little information describing the patterns of PA among Canadian youth, so it is difficult to determine where the deficits occur. The purpose of this study was to identify subgroups of youth and windows of time characterized by low PA and high sedentary behaviour. We conducted a cross-sectional study of 626 youth (aged 10-15 years) in 2 Canadian provinces. The primary exposure variables included geographic setting (rural vs. urban), sex, and days of the week (weekend days vs. weekdays). The primary outcome measures were minutes of light PA, moderate to vigorous physical activity (MVPA), and sedentary behavior, assessed with accelerometry. Compared with weekdays, MVPA was ∼30% lower on weekend days (55.8 ± 23.0 min vs. 38.7 ± 26.7 min; p < 0.001), whereas light PA was ∼15% higher. Significantly more youth achieved an average of >60 min of MVPA on weekdays than on weekend days (46% vs. 22%; p < 0.001). Sex-specific differences in MVPA were more pronounced on weekdays than on weekend days (∼13 vs ∼8 min per day; p < 0.01). Youth in rural settings achieved ∼9 fewer minutes of MVPA daily than youth in urban settings (p < 0.001). In youth 10 to 15 years of age, daily MVPA is lower and light PA is higher on weekend days than on weekdays. Girls and students living in rural areas were particularly vulnerable to low levels of MVPA.

  1. The impact of the built environment on young people's physical activity patterns: a suburban-rural comparison using GPS.

    PubMed

    Collins, Peter; Al-Nakeeb, Yahya; Nevill, Alan; Lyons, Mark

    2012-08-24

    The built environment in which young people live has a significant influence on their physical activity (PA). However, little is known regarding how youth from suburban and rural settings utilise their surrounding environments to participate in free-living PA. 50 adolescents aged 13-14 years old (22 rural; 28 suburban) wore an integrated GPS and heart rate device during non-school hours and completed a daily PA diary over 7 days. Descriptive statistics and analyses of variance were used to explore differences in the amount and location of moderate-to-vigorous physical activity (MVPA) between genders and youth from different geographical settings. Suburban youth participated in significantly (p = 0.004) more daily PA (52.14 minutes MVPA) and were more extensive in their utilisation of their surroundings, compared to rural youth (26.61 minutes MVPA). Suburban youth visited more public recreational facilities and spent significantly more time outdoors and on local streets (109.71 minutes and 44.62 minutes, respectively) compared to rural youth (55.98 minutes and 17.15 minutes, respectively) during weekdays. Rural youth on average spent significantly more time within the home (350.69 minutes) during weekends compared to suburban youth (214.82 minutes). Rural females were the least active group of adolescents, participating in the least amount of daily PA (20.14 minutes MVPA) and spending the least amount of time outdoors (31.37 minutes) during weekdays. Time spent outdoors was positively associated with PA. The findings highlight the disparity in PA levels and the utilisation of the surrounding built environment between youth from two different geographical settings and possible environmental causes are discussed. The study supports the use of GPS (combined with other methods) in investigating geographical differences in young people's PA and movement patterns. This method provides a wealth of information that may assist future policies and interventions in identifying

  2. Genome-Wide Association Study for Circulating Tissue Plasminogen Activator (tPA) Levels and Functional Follow-up Implicates Endothelial STXBP5 and STX2

    PubMed Central

    Huang, Jie; Huffman, Jennifer E.; Yamkauchi, Munekazu; Trompet, Stella; Asselbergs, Folkert W.; Sabater-Lleal, Maria; Trégouët, David-Alexandre; Chen, Wei-Min; Smith, Nicholas L.; Kleber, Marcus E.; Shin, So-Youn; Becker, Diane M.; Tang, Weihong; Dehghan, Abbas; Johnson, Andrew D.; Truong, Vinh; Folkersen, Lasse; Yang, Qiong; Oudot-Mellakh, Tiphaine; Buckley, Brendan M.; Moore, Jason H.; Williams, Frances M.K.; Campbell, Harry; Silbernagel, Günther; Vitart, Veronique; Rudan, Igor; Tofler, Geoffrey H.; Navis, Gerjan J.; DeStefano, Anita; Wright, Alan F.; Chen, Ming-Huei; de Craen, Anton J.M.; Worrall, Bradford B.; Rudnicka, Alicja R.; Rumley, Ann; Bookman, Ebony B.; Psaty, Bruce M.; Chen, Fang; Keene, Keith L.; Franco, Oscar H.; Böhm, Bernhard O.; Uitterlinden, Andre G.; Carter, Angela M.; Jukema, J. Wouter; Sattar, Naveed; Bis, Joshua C.; Ikram, Mohammad A.; Sale, Michèle M.; McKnight, Barbara; Fornage, Myriam; Ford, Ian; Taylor, Kent; Slagboom, P. Eline; McArdle, Wendy L.; Hsu, Fang-Chi; Franco-Cereceda, Anders; Goodall, Alison H.; Yanek, Lisa R.; Furie, Karen L.; Cushman, Mary; Hofman, Albert; Witteman, Jacqueline CM.; Folsom, Aaron R.; Basu, Saonli; Matijevic, Nena; van Gilst, Wiek H.; Wilson, James F.; Westendorp, Rudi G.J.; Kathiresan, Sekar; Reilly, Muredach P.; Tracy, Russell P.; Polasek, Ozren; Winkelmann, Bernhard R.; Grant, Peter J.; Hillege, Hans L.; Cambien, Francois; Stott, David J.; Lowe, Gordon D.; Spector, Timothy D.; Meigs, James B.; Marz, Winfried; Eriksson, Per; Becker, Lewis C.; Morange, Pierre-Emmanuel; Soranzo, Nicole; Williams, Scott M.; Hayward, Caroline; van der Harst, Pim; Hamsten, Anders; Lowenstein, Charles J.; Strachan, David P.; O'Donnell, Christopher J.

    2014-01-01

    Objective Tissue plasminogen activator (tPA), a serine protease, catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for endogenous fibrinolysis. In some populations, elevated plasma levels of tPA have been associated with myocardial infarction and other cardiovascular diseases (CVD). We conducted a meta-analysis of genome-wide association studies (GWAS) to identify novel correlates of circulating levels of tPA. Approach and Results Fourteen cohort studies with tPA measures (N=26,929) contributed to the meta-analysis. Three loci were significantly associated with circulating tPA levels (P <5.0×10−8). The first locus is on 6q24.3, with the lead SNP (rs9399599, P=2.9×10−14) within STXBP5. The second locus is on 8p11.21. The lead SNP (rs3136739, P=1.3×10−9) is intronic to POLB and less than 200kb away from the tPA encoding gene PLAT. We identified a non-synonymous SNP (rs2020921) in modest LD with rs3136739 (r2 = 0.50) within exon 5 of PLAT (P=2.0×10−8). The third locus is on 12q24.33, with the lead SNP (rs7301826, P=1.0×10−9) within intron 7 of STX2. We further found evidence for association of lead SNPs in STXBP5 and STX2 with expression levels of the respective transcripts. In in vitro cell studies, silencing STXBP5 decreased release of tPA from vascular endothelial cells, while silencing of STX2 increased tPA release. Through an in-silico lookup, we found no associations of the three lead SNPs with coronary artery disease or stroke. Conclusions We identified three loci associated with circulating tPA levels, the PLAT region, STXBP5 and STX2. Our functional studies implicate a novel role for STXBP5 and STX2 in regulating tPA release. PMID:24578379

  3. Iron oxide nanoparticles protected by NIR-active multidentate-polymers as multifunctional nanoprobes for NIRF/PA/MR trimodal imaging.

    PubMed

    Wu, Yayun; Gao, Duyang; Zhang, Pengfei; Li, Chuansheng; Wan, Qian; Chen, Chi; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Cai, Lintao

    2016-01-14

    We designed and synthesized new kinds of near-infrared catechol-based multidentate polymers which were intended to yield compact NIR-active iron oxide nanoparticles with excellent stability and biocompatibility. The resulted multifunctional nanoprobes showed great potential as multimodal contrast agents for NIRF/PA/MR trimodal imaging in vivo.

  4. Tissue-type Plasminogen Activator (tPA) Modulates the Postsynaptic Response of Cerebral Cortical Neurons to the Presynaptic Release of Glutamate

    PubMed Central

    Jeanneret, Valerie; Wu, Fang; Merino, Paola; Torre, Enrique; Diaz, Ariel; Cheng, Lihong; Yepes, Manuel

    2016-01-01

    Tissue-type plasminogen activator (tPA) is a serine proteinase released by the presynaptic terminal of cerebral cortical neurons following membrane depolarization (Echeverry et al., 2010). Recent studies indicate that the release of tPA triggers the synaptic vesicle cycle and promotes the exocytosis (Wu et al., 2015) and endocytic retrieval (Yepes et al., 2016) of glutamate-containing synaptic vesicles. Here we used electron microscopy, proteomics, quantitative phosphoproteomics, biochemical analyses with extracts of the postsynaptic density (PSD), and an animal model of cerebral ischemia with mice overexpressing neuronal tPA to study whether the presynaptic release of tPA also has an effect on the postsynaptic terminal. We found that tPA has a bidirectional effect on the composition of the PSD of cerebral cortical neurons that is independent of the generation of plasmin and the presynaptic release of glutamate, but depends on the baseline level of neuronal activity and the extracellular concentrations of calcium (Ca2+). Accordingly, in neurons that are either inactive or incubated with low Ca2+ concentrations tPA induces phosphorylation and accumulation in the PSD of the Ca2+/calmodulin-dependent protein kinase IIα (pCaMKIIα), followed by pCaMKIIα-mediated phosphorylation and synaptic recruitment of GluR1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. In contrast, in neurons with previously increased baseline levels of pCaMKIIα in the PSD due to neuronal depolarization in vivo or incubation with high concentrations of either Ca2+ or glutamate in vitro, tPA induces pCaMKIIα and pGluR1 dephosphorylation and their subsequent removal from the PSD. We found that these effects of tPA are mediated by synaptic N-methyl-D-aspartate (NMDA) receptors and cyclin-dependent kinase 5 (Cdk5)-induced phosphorylation of the protein phosphatase 1 (PP1) at T320. Our data indicate that by regulating the pCaMKIIα/PP1 balance in the PSD tPA acts

  5. Understanding human activity patterns based on space-time-semantics

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Li, Songnian

    2016-11-01

    Understanding human activity patterns plays a key role in various applications in an urban environment, such as transportation planning and traffic forecasting, urban planning, public health and safety, and emergency response. Most existing studies in modeling human activity patterns mainly focus on spatiotemporal dimensions, which lacks consideration of underlying semantic context. In fact, what people do and discuss at some places, inferring what is happening at the places, cannot be simple neglected because it is the root of human mobility patterns. We believe that the geo-tagged semantic context, representing what individuals do and discuss at a place and a specific time, drives a formation of specific human activity pattern. In this paper, we aim to model human activity patterns not only based on space and time but also with consideration of associated semantics, and attempt to prove a hypothesis that similar mobility patterns may have different motivations. We develop a spatiotemporal-semantic model to quantitatively express human activity patterns based on topic models, leading to an analysis of space, time and semantics. A case study is conducted using Twitter data in Toronto based on our model. Through computing the similarities between users in terms of spatiotemporal pattern, semantic pattern and spatiotemporal-semantic pattern, we find that only a small number of users (2.72%) have very similar activity patterns, while the majority (87.14%) show different activity patterns (i.e., similar spatiotemporal patterns and different semantic patterns, similar semantic patterns and different spatiotemporal patterns, or different in both). The population of users that has very similar activity patterns is decreased by 56.41% after incorporating semantic information in the corresponding spatiotemporal patterns, which can quantitatively prove the hypothesis.

  6. Sleep patterns in Spanish adolescents: associations with TV watching and leisure-time physical activity.

    PubMed

    Ortega, Francisco B; Chillón, Palma; Ruiz, Jonatan R; Delgado, Manuel; Albers, Ulrike; Alvarez-Granda, Jesús L; Marcos, Ascensión; Moreno, Luis A; Castillo, Manuel J

    2010-10-01

    We aimed to describe the sleep patterns in Spanish adolescents and to examine the relationships of sleep duration and morning tiredness with participation in leisure-time physical-sporting activities (LT-PA) and television (TV) watching. Sleep duration, morning tiredness, participation in LT-PA and time spent on watching TV were reported by 2,179 (1,139 females) Spanish adolescents (AVENA study). Data were analyzed by binary logistic regression. One-fifth of the adolescents reported insufficient night sleep (<8 h) on school days. The review of the literature (30 studies) showed that the Spanish adolescents sleep as long as adolescents from central Europe, and longer than those from other Mediterranean countries, South Africa, Asia and North America. Insufficient sleep duration doubled the odds of excessive TV watching (≥3 h/day) in males, regardless of morning tiredness (OR 2.15, 95% CI 1.42-3.27). Morning tiredness reduced the odds of participating in any LT-PA in both males and females (0.49, 0.34-0.70 and 0.49, 0.35-0.69, respectively), and increased the odds of excessive TV watching in females, regardless of sleep duration (2.49, 1.64-3.79). We conclude that non-participation in LT-PA is associated with morning tiredness in male and female adolescents, while excessive TV watching is more associated with short sleep or morning tiredness depending on gender.

  7. Synergistic transcriptional activation of the mouse urokinase plasminogen activator (uPA) gene and of its enhancer activator protein 1 (AP1) site by cAMP and retinoic acid.

    PubMed Central

    Mira-Y-Lopez, R; Jaramillo, S; Jing, Y

    1998-01-01

    We have investigated the mechanism whereby all-trans retinoic acid (tRA) potentiates the 8-bromo-cAMP (8-BrcAMP)-dependent transcription of the urokinase plasminogen activator (uPA) gene in SC115 mouse mammary carcinoma cells. Photoaffinity labelling experiments showed that tRA did not alter the cellular content of cAMP-dependent protein kinase regulatory subunits I and II. In agreement with this, nuclear run-on analysis in the presence of the translational inhibitor puromycin demonstrated that the effect of 8-BrcAMP and its potentiation by tRA were independent of protein synthesis. A transiently transfected 6.6 kb uPA 5'-flanking region-chloramphenicol acetyltransferase (CAT) fusion gene mimicked the response of the endogenous uPA gene. Thus 1 mM 8-BrcAMP induced a 100-200% increase in CAT content, 100 nM tRA had no effect and 100 nM tRA+1 mM 8-BrcAMP induced a 300-500% increase in cells co-transfected with tRA receptor and/or 9-cis-RA receptor. Analysis of 5'-deleted constructs showed that the tRA effect required at least two cis regions: -2657 to -2186, encompassing the 100 bp uPA enhancer, and -709 to -324, which exhibited silencing activity. Neither region contained a tRA-response element-like motif. Because tRA receptor and 9-cis-RA receptor interact with activator protein 1 (AP1), we tested whether tRA regulated the uPA enhancer AP1 site in the presence of 8-BrcAMP. We found that a dimer of this site fused to a minimal uPA-CAT fusion gene was responsive to 1 mM 8-BrcAMP (100% CAT increase), not responsive to 100 nM tRA, and synergistically responsive to 100 nM tRA+1 mM 8-BrcAMP (240% CAT increase) in cells co-transfected with Fos and Jun. Synergistic activation of the same construct and of the 6.6 kb uPA-CAT fusion gene was also obtained using tRA and 100 nM PMA. We conclude that multiple cis elements, probably including the uPA enhancer AP1 site, mediate the tRA potentiation of uPA transcription. PMID:9560322

  8. 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.

  9. Iron oxide nanoparticles protected by NIR-active multidentate-polymers as multifunctional nanoprobes for NIRF/PA/MR trimodal imaging

    NASA Astrophysics Data System (ADS)

    Wu, Yayun; Gao, Duyang; Zhang, Pengfei; Li, Chuansheng; Wan, Qian; Chen, Chi; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Cai, Lintao

    2015-12-01

    We designed and synthesized new kinds of near-infrared catechol-based multidentate polymers which were intended to yield compact NIR-active iron oxide nanoparticles with excellent stability and biocompatibility. The resulted multifunctional nanoprobes showed great potential as multimodal contrast agents for NIRF/PA/MR trimodal imaging in vivo.We designed and synthesized new kinds of near-infrared catechol-based multidentate polymers which were intended to yield compact NIR-active iron oxide nanoparticles with excellent stability and biocompatibility. The resulted multifunctional nanoprobes showed great potential as multimodal contrast agents for NIRF/PA/MR trimodal imaging in vivo. Electronic supplementary information (ESI) available: Details of the experiment and Fig. S1-S6. See DOI: 10.1039/c5nr06660c

  10. Source and Type of Support for In-School Physical Activity: Differential Patterns for Demographic Subgroups

    ERIC Educational Resources Information Center

    Kulik, Noel L.; Somers, Cheryl L.; Thomas, Erica; Martin, Jeffrey J.; Centeio, Erin E.; Garn, Alex C.; Shen, Bo; McCaughtry, Nathan

    2015-01-01

    Background: Results of prior research on social support (SS) for physical activity (PA) have been inconsistent. Purpose: The study aim was to expand the SS and PA literature by focusing on children, examining associated variables such as weight, race/ethnicity, and sex, and use objectively measured PA and inclusive targets of SS. Methods:…

  11. PtrA Is Functionally Intertwined with GacS in Regulating the Biocontrol Activity of Pseudomonas chlororaphis PA23

    PubMed Central

    Shah, Nidhi; Klaponski, Natasha; Selin, Carrie; Rudney, Rachel; Fernando, W. G. Dilantha; Belmonte, Mark F.; de Kievit, Teresa R.

    2016-01-01

    In vitro inhibition of the fungal pathogen Sclerotinia sclerotiorum by Pseudomonas chlororaphis PA23 is reliant upon a LysR-type transcriptional regulator (LTTR) called PtrA. In the current study, we show that Sclerotinia stem rot and leaf infection are significantly increased in canola plants inoculated with the ptrA-mutant compared to the wild type, establishing PtrA as an essential regulator of PA23 biocontrol. LTTRs typically regulate targets that are upstream of and divergently transcribed from the LTTR locus. We identified a short chain dehydrogenase (scd) gene immediately upstream of ptrA. Characterization of a scd mutant revealed that it is phenotypically identical to the wild type. Moreover, scd transcript abundance was unchanged in the ptrA mutant. These findings indicate that PtrA regulation does not involve scd, rather this LTTR controls genes located elsewhere on the chromosome. Employing a combination of complementation and transcriptional analysis we investigated whether connections exist between PtrA and other regulators of biocontrol. Besides ptrA, gacS was the only gene able to partially rescue the wild-type phenotype, establishing a connection between PtrA and the sensor kinase GacS. Transcriptomic analysis revealed decreased expression of biosynthetic (phzA, prnA) and regulatory genes (phzI, phzR, rpoS, gacA, rsmX, rsmZ, retS) in the ptrA mutant; conversely, rsmE, and rsmY were markedly upregulated. The transcript abundance of ptrA was nine-fold higher in the mutant background indicating that this LTTR negatively autoregulates itself. In summary, PtrA is an essential regulator of genes required for PA23 biocontrol that is functionally intertwined with GacS. PMID:27713742

  12. 26S and PA28-20S Proteasome Activity in Cytosolic Extracts from Embryonic Stem Cells.

    PubMed

    Hernebring, Malin

    2016-01-01

    The proteasome is a complex multisubunit protease that plays a major role in the degradation of proteins in eukaryotic cells. Proteasome function is one of the key players regulating the proteome and it is vital for many cellular processes. The method described here makes it possible to assay the proteolytic capacities of proteasome complexes separately in crude cytosolic extracts from ES cells. The method is based on hydrolysis of a fluorogenic peptide substrate in lysates prepared under conditions that favor the interactions of the 20S proteasomal catalytical core with either the 19S or the PA28αβ proteasome regulator.

  13. Double dose: the cumulative effect of TV viewing at home and in preschool on children's activity patterns and weight status.

    PubMed

    Taverno Ross, Sharon; Dowda, Marsha; Saunders, Ruth; Pate, Russell

    2013-05-01

    Little is known about how screen-based sedentary behavior at home and in preschool influences children's health and activity patterns. The current study examined the individual and cumulative influence of TV viewing at home and in preschool on children's physical activity (PA) and weight status. Children (n = 339) attending 16 preschools in South Carolina were grouped into high and low TV groups based on parent report of children's TV viewing at home and director report of TV use/rules in preschool. T-tests and mixed model ANOVAs examined differences in weight status and PA (min/hr) by high and low TV groups. Results revealed that children who were classified as High TV both at home and in pre- school had significantly lower levels of moderate-to-vigorous PA compared with their Low TV counterparts (8.3 (0.3) min/hr vs. 7.6 (0.2) min/hr, p < .05). However, there were no significant differences in weight status or physical activity between the high and low TV groups at home or in preschool when examined individually. These findings demonstrate the importance of total environmental TV exposure on preschooler's PA. Longitudinal and observational research to assess preschoolers' cumulative screen-based sedentary behavior and its relationship with PA and weight status is needed.

  14. 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.

  15. 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…

  16. MUSCLE ACTIVATION PATTERNS DURING SUSPENSION TRAINING EXERCISES

    PubMed Central

    Harris, Sean; Ruffin, Elise; Brewer, Wayne

    2017-01-01

    Background Suspension training (ST) has been utilized over exercises performed on a stable surface to train multiple muscle groups simultaneously to increase muscle activation and joint stability. Hypothesis/Purpose The purpose of this study was to determine whether ST augments muscle activation compared to similar exercises performed on a stable surface. Study Design Cross-sectional study Methods Twenty-five healthy adults (male: 16; women: 9; BMI: 23.50 ± 2.48 kg/m2) had 16 pre-amplified wireless surface EMG electrodes placed bilaterally on: the pectoralis major (PM), middle deltoid (MD), serratus anterior (SA), obliques (OB), rectus abdominis (RA), gluteus maximus (GM), erector spinae (ES), and middle trapezius/rhomboids (MT). Each participant performed reference isometric exercises (Sorensen test, push-up, sit-up, and inverted row) to establish a baseline muscle contraction. Muscle activation was assessed during the following exercises: ST bridge, ST push-up, ST inverted row, ST plank, floor bridge, floor push-up, floor row, and floor plank. The root mean square (RMS) of each side for every muscle was averaged for data analysis. Multivariate analyses of variance (MANOVA) for each exercise with post-hoc comparisons were performed to compare muscle activation between each ST exercise and its stable surface counterpart. Results MANOVAs for all exercise comparisons showed statistically significant greater muscle activation in at least one muscle group during the ST condition. Post-hoc analyses revealed a statistically significant increase in muscle activation for the following muscles during the plank: OB (p = 0.021); Push-up: PM (p = 0.002), RA (p<0.0001), OB (p = 0.019), MT (p<0.0001), and ES (p = 0.006); Row: MD (p = 0.016), RA (p = 0.059), and OB (p = 0.027); and Bridge: RA (p = 0.013) and ES (p<0.0001). Conclusions Performing ST exercises increases muscle activation of selected muscles when compared to exercises performed on a stable surface. Level of

  17. Physical Activity Patterns in Normal-Weight and Overweight/Obese Pregnant Women

    PubMed Central

    Bacchi, Elisabetta; Bonin, Cecilia; Zanolin, Maria Elisabetta; Zambotti, Francesca; Livornese, Dario; Donà, Silvia; Tosi, Flavia; Baldisser, Giulia; Ihnatava, Tatsiana; Di Sarra, Daniela; Bonora, Enzo; Moghetti, Paolo

    2016-01-01

    The aims of the present study were to assess the volume of physical activity (PA) throughout pregnancy in normal-weight vs overweight/obese women, and to investigate which factors may predict compliance to PA recommendations in these women throughout gestation. In 236 pregnant women, 177 normal-weight and 59 overweight/obese (median[IQR] BMI 21.2[19.9–22.8] vs 26.5[25.5–29.0] kg/m2, respectively), medical history, anthropometry and clinical data, including glucose tolerance, were recorded. In addition, pre-pregnancy PA was estimated by the Kaiser questionnaire, while total, walking and fitness/sport PA during pregnancy were assessed by the Physical Activity Scale for the Elderly (PASE) modified questionnaire, at 14–16, 24–28 and 30–32 weeks of gestation. PA volume was very low in the first trimester of pregnancy in both groups of women. However, it increased in the second and third trimester in normal-weight, but not in overweight/obese subjects. Higher pre-pregnancy PA was a statistically significant predictor of being physically active (>150 minutes of PA per week) during all trimesters of gestation. In conclusion, physical activity volume is low in pregnant women, especially in overweight/obese subjects. PA volume increases during pregnancy only in normal-weight women. Pre-pregnancy PA is an independent predictor of achieving a PA volume of at least 150 min per week during pregnancy. PMID:27829017

  18. 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…

  19. Antibacterial Activity of Defensin PaDef from Avocado Fruit (Persea americana var. drymifolia) Expressed in Endothelial Cells against Escherichia coli and Staphylococcus aureus

    PubMed Central

    Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Suárez-Rodríguez, Luis M.; Salgado-Garciglia, Rafael; Rodríguez-Zapata, Luis C.; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E.

    2013-01-01

    Antimicrobial therapy is a useful tool to control infectious diseases in general and rising antibiotic resistant microorganisms in particular. Alternative strategies are desirable, and antimicrobial peptides (AMP) represent attractive control agents. Mexican avocado (Persea americana var. drymifolia) is used in traditional medicine; however, the AMP production has not been reported in this plant. We obtained a cDNA library from avocado fruit and clone PaDef was identified, which has a cDNA (249 bp) encoding a protein (78 aa) homologous with plant defensins (>80%). We expressed the defensin PaDef cDNA (pBME3) in the bovine endothelial cell line BVE-E6E7. Polyclonal and clonal populations were obtained and their activity was evaluated against Escherichia coli, Staphylococcus aureus, and Candida albicans. E. coli viability was inhibited with 100 μg/mL of total protein from clones (>55%). Also, S. aureus viability was inhibited from 50 μg/mL total protein (27–38%) but was more evident at 100 μg/mL (52–65%). This inhibition was higher than the effect showed by polyclonal population (~23%). Finally, we did not detect activity against C. albicans. These results are the first report that shows antimicrobial activity of a defensin produced by avocado and suggest that this AMP could be used in the control of pathogens. PMID:24319695

  20. Defense activation triggers differential expression of phospholipase-C (PLC) genes and elevated temperature induces phosphatidic acid (PA) accumulation in tomato

    PubMed Central

    Abd-El-Haliem, Ahmed; Meijer, Harold J.G.; Tameling, Wladimir I.L.; Vossen, Jack H.; Joosten, Matthieu H.A.J.

    2012-01-01

    Recently, we provided the first genetic evidence for the requirement of tomato PLC4 and PLC6 genes in defense activation and disease resistance. The encoded enzymes were catalytically active as they were able to degrade phosphatidylinositol (PI), thereby producing diacylglycerol (DG). Here we report differential PLC gene expression following the initiation of defense signaling by the interaction between Cladosporium fulvum resistance (R) protein Cf-4 and its matching effector Avr4 in tomato hybrid seedlings that express both Cf-4 and Avr4. Furthermore, we observed that PLC3 and PLC6 gene expression is upregulated by elevated temperature in the control seedlings. This upregulation coincides with an increase in the levels of phosphatidic acid (PA) and a decrease in the levels of PI and phosphatidylinositol phosphate (PIP). The decrease in PI and PIP levels matches with the activation of PLC. In addition, the levels of the structural phospholipids phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) declined transiently during recovery after the exposure to elevated temperature., Further studies will be required to explain the mechanism causing the sustained accumulation of PA during recovery, combined with a reduction in the levels of structural phospholipids. PMID:22899083

  1. Antibacterial activity of defensin PaDef from avocado fruit (Persea americana var. drymifolia) expressed in endothelial cells against Escherichia coli and Staphylococcus aureus.

    PubMed

    Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Suárez-Rodríguez, Luis M; Salgado-Garciglia, Rafael; Rodríguez-Zapata, Luis C; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

    2013-01-01

    Antimicrobial therapy is a useful tool to control infectious diseases in general and rising antibiotic resistant microorganisms in particular. Alternative strategies are desirable, and antimicrobial peptides (AMP) represent attractive control agents. Mexican avocado (Persea americana var. drymifolia) is used in traditional medicine; however, the AMP production has not been reported in this plant. We obtained a cDNA library from avocado fruit and clone PaDef was identified, which has a cDNA (249 bp) encoding a protein (78 aa) homologous with plant defensins (>80%). We expressed the defensin PaDef cDNA (pBME3) in the bovine endothelial cell line BVE-E6E7. Polyclonal and clonal populations were obtained and their activity was evaluated against Escherichia coli, Staphylococcus aureus, and Candida albicans. E. coli viability was inhibited with 100 μg/mL of total protein from clones (>55%). Also, S. aureus viability was inhibited from 50 μg/mL total protein (27-38%) but was more evident at 100 μg/mL (52-65%). This inhibition was higher than the effect showed by polyclonal population (~23%). Finally, we did not detect activity against C. albicans. These results are the first report that shows antimicrobial activity of a defensin produced by avocado and suggest that this AMP could be used in the control of pathogens.

  2. Pattern recognition and active vision in chickens.

    PubMed

    Dawkins, M S; Woodington, A

    2000-02-10

    Recognition of objects or environmental landmarks is problematic because appearance can vary widely depending on illumination, viewing distance, angle of view and so on. Storing a separate image or 'template' for every possible view requires vast numbers to be stored and scanned, has a high probability of recognition error and appears not to be the solution adopted by primates. However, some invertebrate template matching systems can achieve recognition by 'active vision' in which the animal's own behaviour is used to achieve a fit between template and object, for example by repeatedly following a set path. Recognition is thus limited to views from the set path but achieved with a minimal number of templates. Here we report the first evidence of similar active vision in a bird, in the form of locomotion and individually distinct head movements that give the eyes a similar series of views on different occasions. The hens' ability to recognize objects is also found to decrease when their normal paths are altered.

  3. Optic foramen morphology and activity pattern in birds.

    PubMed

    Hall, Margaret I; Iwaniuk, Andrew N; Gutiérrez-Ibáñez, Cristián

    2009-11-01

    The optic nerve is the sole output of visual information from the ganglion cell layer of the retina to the brain in vertebrates. The size of the optic nerve is predicted to be closely associated with activity pattern, and, in many birds, the size of the optic foramen approximates the size of the optic nerve. Specifically, nocturnal species should have relatively smaller optic foramina than diurnal species because of differences in retinal pooling between activity patterns. If optic foramen morphology varies predictably with activity pattern in birds, this variable may be useful for interpreting activity pattern for birds that do not have soft tissue available for study, specifically for fossils. Across 177 families (from 27 orders), we describe four different optic foramen morphologies, only one of which corresponds well with the size of the optic nerve and is therefore appropriate for activity pattern analyses. Here, we test our hypothesis that nocturnal species will have relatively smaller optic foramina than diurnal species, across all species that we measured that have a discrete optic foramen. Regression analyses using species as independent data points and using comparative methods yielded significant differences in optic foramen size between nocturnal and diurnal species relative to three variables: head length, orbit depth, and sclerotic ring inner diameter. Nocturnal species consistently exhibit significantly smaller relative optic foramen diameters than diurnal species. Our results indicate that optic foramen diameter, in combination with either the sclerotic ring or the orbit diameter, can be used to predict activity pattern.

  4. 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.

  5. Prevalence, Patterns and Correlates of Physical Activity among the Adult Population of the Southern Cone of Latin America: Cross-Sectional Results from the CESCAS I Study

    PubMed Central

    Poggio, Rosana; Serón, Pamela; Calandrelli, Matías; Ponzo, Jacqueline; Mores, Nora; Matta, María G; Gutierrez, Laura; Chung-Shiuan, Chen; Lanas, Fernando; He, Jiang; Irazola, Vilma; Rubinstein, Adolfo; Bazzano, Lydia

    2016-01-01

    Objective Few data are available on population level regarding domain-specific correlates of physical activity (PA) in Latin America. The aim of this study was to examine the relationships among PA patterns and their main sociodemographic determinants and cardiovascular risk factors in the Southern Cone of Latin America. Methods CESCAS I is a population-based prospective cohort study with a 4-stage stratified sampling of a general population of 7,524 adults aged 35–74 years from four mid-sized cities in Argentina, Chile and Uruguay. PA was assessed using the transcultural adaptation of the International Physical Activity Questionnaire long form (IPAQ). The questionnaire asked about frequency (days/week) and duration (minutes/day) of moderate and vigorous intensity activities in three different domains: work, leisure time and active transportation (walking and bicycling). PA levels ≥ 600 metabolic equivalent tasks (MET) minutes/week was considered sufficiently active (SA). Odds ratios for associations of SA status with sociodemographic determinants and cardiovascular risk factors were obtained using multivariable-adjusted logistic regression models. Results Almost sixty five percent (64.8%) of the participants reported ≥ 600 MET minutes/week. The lowest prevalence of sufficiently active individuals was seen in Temuco, Chile (58.0 %), among women (58.7%), older individuals (55.4%), those with higher educational level (61.6%) and homemakers (53.4%). Approximately 22.8% of the population reported no PA. In multivariable analysis, PA levels were lower among women, individuals who were older, obese, university educated, with clerical work, retired/unemployed or homemakers, and those with physical limitations. Conclusions Future interventions to increase PA levels in the Southern Cone of Latin America must take into account disparities by gender and socioeconomic status. The promotion of PA during leisure time in women –unemployed and homemakers– and of active

  6. 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

  7. Associative-memory representations emerge as shared spatial patterns of theta activity spanning the primate temporal cortex

    PubMed Central

    Nakahara, Kiyoshi; Adachi, Ken; Kawasaki, Keisuke; Matsuo, Takeshi; Sawahata, Hirohito; Majima, Kei; Takeda, Masaki; Sugiyama, Sayaka; Nakata, Ryota; Iijima, Atsuhiko; Tanigawa, Hisashi; Suzuki, Takafumi; Kamitani, Yukiyasu; Hasegawa, Isao

    2016-01-01

    Highly localized neuronal spikes in primate temporal cortex can encode associative memory; however, whether memory formation involves area-wide reorganization of ensemble activity, which often accompanies rhythmicity, or just local microcircuit-level plasticity, remains elusive. Using high-density electrocorticography, we capture local-field potentials spanning the monkey temporal lobes, and show that the visual pair-association (PA) memory is encoded in spatial patterns of theta activity in areas TE, 36, and, partially, in the parahippocampal cortex, but not in the entorhinal cortex. The theta patterns elicited by learned paired associates are distinct between pairs, but similar within pairs. This pattern similarity, emerging through novel PA learning, allows a machine-learning decoder trained on theta patterns elicited by a particular visual item to correctly predict the identity of those elicited by its paired associate. Our results suggest that the formation and sharing of widespread cortical theta patterns via learning-induced reorganization are involved in the mechanisms of associative memory representation. PMID:27282247

  8. 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

  9. 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…

  10. 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…

  11. Exploring the Role of the Food Environment on Food Shopping Patterns in Philadelphia, PA, USA: A Semiquantitative Comparison of Two Matched Neighborhood Groups

    PubMed Central

    Hirsch, Jana A.; Hillier, Amy

    2013-01-01

    Increasing research has focused on the built food environment and nutrition-related outcomes, yet what constitutes a food environment and how this environment influences individual behavior still remain unclear. This study assesses whether travel mode and distance to food shopping venues differ among individuals in varying food environments and whether individual- and household-level factors are associated with food shopping patterns. Fifty neighbors who share a traditionally defined food environment (25 in an unfavorable environment and 25 in a favorable environment) were surveyed using a mix of close- and open-ended survey questions. Food shopping patterns were mapped using Geographic Information Systems (GIS). Stores visited were beyond the 0.5-mile (805 meters) radius traditionally used to represent the extent of an individual’s food environment in an urban area. We found no significant difference in shopping frequency or motivating factor behind store choice between the groups. No differences existed between the two groups for big food shopping trips. For small trips, individuals in the favorable food environment traveled shorter distances and were more likely to walk than drive. Socioeconomic status, including car ownership, education, and income influenced distance traveled. These findings highlight the complexities involved in the study and measurement of food environments. PMID:23343984

  12. Exploring the role of the food environment on food shopping patterns in Philadelphia, PA, USA: a semiquantitative comparison of two matched neighborhood groups.

    PubMed

    Hirsch, Jana A; Hillier, Amy

    2013-01-14

    Increasing research has focused on the built food environment and nutrition-related outcomes, yet what constitutes a food environment and how this environment influences individual behavior still remain unclear. This study assesses whether travel mode and distance to food shopping venues differ among individuals in varying food environments and whether individual- and household-level factors are associated with food shopping patterns. Fifty neighbors who share a traditionally defined food environment (25 in an unfavorable environment and 25 in a favorable environment) were surveyed using a mix of close- and open-ended survey questions. Food shopping patterns were mapped using Geographic Information Systems (GIS). Stores visited were beyond the 0.5-mile (805 meters) radius traditionally used to represent the extent of an individual's food environment in an urban area. We found no significant difference in shopping frequency or motivating factor behind store choice between the groups. No differences existed between the two groups for big food shopping trips. For small trips, individuals in the favorable food environment traveled shorter distances and were more likely to walk than drive. Socioeconomic status, including car ownership, education, and income influenced distance traveled. These findings highlight the complexities involved in the study and measurement of food environments.

  13. Are muscle activation patterns altered during shod and barefoot running with a forefoot footfall pattern?

    PubMed

    Ervilha, Ulysses Fernandes; Mochizuki, Luis; Figueira, Aylton; Hamill, Joseph

    2016-09-14

    This study aimed to investigate the activation of lower limb muscles during barefoot and shod running with forefoot or rearfoot footfall patterns. Nine habitually shod runners were asked to run straight for 20 m at self-selected speed. Ground reaction forces and thigh and shank muscle surface electromyographic (EMG) were recorded. EMG outcomes (EMG intensity [iEMG], latency between muscle activation and ground reaction force, latency between muscle pairs and co-activation index between muscle pairs) were compared across condition (shod and barefoot), running cycle epochs (pre-strike, strike, propulsion) and footfall (rearfoot and forefoot) by ANOVA. Condition affected iEMG at pre-strike epoch. Forefoot and rearfoot strike patterns induced different EMG activation time patterns affecting co-activation index for pairs of thigh and shank muscles. All these timing changes suggest that wearing shoes or not is less important for muscle activation than the way runners strike the foot on the ground. In conclusion, the guidance for changing external forces applied on lower limbs should be pointed to the question of rearfoot or forefoot footfall patterns.

  14. Patterns of sedentary behaviour and physical activity in people following curative intent treatment for non-small cell lung cancer.

    PubMed

    Cavalheri, Vinicius; Jenkins, Sue; Cecins, Nola; Phillips, Martin; Sanders, Lucas H; Hill, Kylie

    2016-02-01

    This study aimed to compare patterns of sedentary behaviour (SB) and physical activity (PA) in people following curative intent treatment for non-small cell lung cancer (NSCLC) with healthy controls. Participants 6-10 weeks following lobectomy for NSCLC and healthy controls wore two activity monitors for 7 days. Waking hours were divided into time spent in SB (<1.5 metabolic equivalent of tasks (METs)), light intensity PA (LIPA ≥ 1.5 to <3.0METs) and moderate-to-vigorous intensity PA (≥3.0METs). Daily steps were also recorded. Data were available in 20 participants with NSCLC (13 females; 68 ± 10 years) and 20 healthy controls (13 females; 69 ± 5 years). The NSCLC group accumulated a greater percentage of time in SB in uninterrupted bouts ≥30 minutes (49% vs. 42%; p = 0.048). Further, the NSCLC group spent a lower percentage of waking hours in LIPA (21 ± 9% vs. 26 ± 8%; p = 0.04) and accumulated a lower percentage of time in this domain in uninterrupted bouts ≥10 minutes (13% vs. 19%; p = 0.025). The NSCLC group also had a lower daily step count (8863 ± 3737 vs. 11,856 ± 3024 steps/day; p = 0.009). Time spent in moderate-to-vigorous intensity PA was similar in both groups (p = 0.92). People following curative intent treatment for NSCLC spend more time in prolonged bouts of SB at the expense of LIPA.

  15. Acute stroke therapy with tissue plasminogen activator (tPA) since it was approved by the U.S. Food and Drug Administration (FDA).

    PubMed

    Zivin, Justin A

    2009-07-01

    Tissue plasminogen activator (tPA) for acute ischemic stroke was approved by the U.S. Food and Drug Administration (FDA) in 1996. Since then it has been severely underutilized. At the time when most practitioners were first being exposed to the literature concerning tPA, there were many concerns about safety and the restrictions on use were quite onerous. Since then a good deal of further work has been done to loosen the restrictions and allay concerns about the risks. The true risk to benefit ratio is far better than is generally realized. Now it is mostly economic problems related to the costs of constantly supplying emergency care that is limiting access. Furthermore, in the current litigious environment, failure to treat is likely to be a more hazardous course of action than legal exposure due to poor outcomes. It must be emphasized that the drug is quite safe and highly effective, and current utilization rates are unacceptably low. Ann Neurol 2009;66:6-10.

  16. Plasticity of recurring spatiotemporal activity patterns in cortical networks

    NASA Astrophysics Data System (ADS)

    Madhavan, Radhika; Chao, Zenas C.; Potter, Steve M.

    2007-09-01

    How do neurons encode and store information for long periods of time? Recurring patterns of activity have been reported in various cortical structures and were suggested to play a role in information processing and memory. To study the potential role of bursts of action potentials in memory mechanisms, we investigated patterns of spontaneous multi-single-unit activity in dissociated rat cortical cultures in vitro. Spontaneous spikes were recorded from networks of approximately 50 000 neurons and glia cultured on a grid of 60 extracellular substrate- embedded electrodes (multi-electrode arrays). These networks expressed spontaneous culture- wide bursting from approximately one week in vitro. During bursts, a large portion of the active electrodes showed elevated levels of firing. Spatiotemporal activity patterns within spontaneous bursts were clustered using a correlation-based clustering algorithm, and the occurrences of these burst clusters were tracked over several hours. This analysis revealed spatiotemporally diverse bursts occurring in well-defined patterns, which remained stable for several hours. Activity evoked by strong local tetanic stimulation resulted in significant changes in the occurrences of spontaneous bursts belonging to different clusters, indicating that the dynamical flow of information in the neuronal network had been altered. The diversity of spatiotemporal structure and long-term stability of spontaneous bursts together with their plastic nature strongly suggests that such network patterns could be used as codes for information transfer and the expression of memories stored in cortical networks.

  17. Oxidation of gas-phase protactinium ions, Pa+ and Pa2+: formation and properties of PaO2(2+)(g), protactinyl.

    PubMed

    Santos, Marta; de Matos, António Pires; Marçalo, Joaquim; Gibson, John K; Haire, Richard G; Tyagi, Rajni; Pitzer, Russell M

    2006-05-04

    Oxidation reactions of bare and ligated, monopositive, and dipositive Pa ions in the gas phase were studied by Fourier transform ion cyclotron resonance mass spectrometry. Seven oxidants were employed, ranging from the thermodynamically robust N(2)O to the relatively weak CH(2)O-all oxidized Pa(+) to PaO(+) and PaO(+) to PaO(2)(+). On the basis of experimental observations, it was established that D[Pa(+)-O] and D[OPa(+)-O] > or = 751 kJ mol(-1). Estimates for D[Pa(+)-O], D[OPa(+)-O], IE[PaO], and IE[PaO(2)] were also obtained. The seven oxidants reacted with Pa(2+) to produce PaO(2+), indicating that D[Pa(2+)-O] > or = 751 kJ mol(-1). A particularly notable finding was the oxidation of PaO(2+) by N(2)O to PaO(2)(2+), a species, which formally comprises Pa(VI). Collision-induced dissociation of PaO(2)(2+) suggested the protactinyl connectivity, {O-Pa-O}(2+). The experimentally determined IE[PaO(2)(+)] approximately 16.6 eV is in agreement with self-consistent-field and configuration interaction calculations for PaO(2)(+) and PaO(2)(2+). These calculations provide insights into the electronic structures of these ions and indicate the participation of 5f orbitals in bonding and a partial "6p hole" in the case of protactinyl. It was found that PaO(2)(2+) catalyzes the oxidation of CO by N(2)O-such O atom transport via a dipositive metal oxide ion is distinctive. It was also observed that PaO(2)(2+) is capable of activating H(2) to form the stable PaO(2)H(2+) ion.

  18. 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.

  19. 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.

  20. Sitting Time, Physical Activity and Sleep by Work Type and Pattern-The Australian Longitudinal Study on Women's Health.

    PubMed

    Clark, Bronwyn K; Kolbe-Alexander, Tracy L; Duncan, Mitch J; Brown, Wendy

    2017-03-10

    Data from the Australian Longitudinal Study on Women's Health were used to examine how work was associated with time spent sleeping, sitting and in physical activity (PA), in working women. Young (31-36 years; 2009) and mid-aged (59-64 years; 2010) women reported sleep (categorised as shorter ≤6 h/day and longer ≥8 h/day) and sitting time (work, transport, television, non-work computer, and other; summed for total sitting time) on the most recent work and non-work day; and moderate and vigorous PA (categorised as meeting/not meeting guidelines) in the previous week. Participants reported occupation (manager/professional; clerical/sales; trades/transport/labourer), work hours (part-time; full-time) and work pattern (shift/night; not shift/night). The odds of shorter sleep on work days was higher in both cohorts for women who worked shift or night hours. Longer sitting time on work days, made up primarily of sitting for work, was found for managers/professionals, clerical/sales and full-time workers. In the young cohort, clerical/sales workers and in the mid-aged cohort, full-time workers were less likely to meet PA guidelines. These results suggest multiple behaviour interventions tailored to work patterns and occupational category may be useful to improve the sleep, sitting and activity of working women.

  1. Mechanisms underlying spontaneous patterned activity in developing neural circuits

    PubMed Central

    Blankenship, Aaron G.; Feller, Marla B.

    2010-01-01

    Patterned, spontaneous activity occurs in many developing neural circuits, including the retina, the cochlea, the spinal cord, the cerebellum and the hippocampus, where it provides signals that are important for the development of neurons and their connections. Despite differences in adult architecture and output across these various circuits, the patterns of spontaneous network activity and the mechanisms that generate it are remarkably similar and can include a depolarizing action of GABA, transient synaptic connections, extrasynaptic transmission, gap junction coupling and the presence of pacemaker-like neurons. Interestingly, spontaneous activity is robust; if one element of a circuit is disrupted another will generate similar activity. This research suggests that developing neural circuits exhibit transient and tunable features that maintain a source of correlated activity during critical stages of development. PMID:19953103

  2. Lifelong physical activity patterns of sedentary Mexican American women.

    PubMed

    Cromwell, Sandra L; Berg, Judith A

    2006-01-01

    Increasing physical activity, especially for high-risk groups, is a national priority; yet little is known about the lifelong patterns of physical activity of older Mexican American women. This article describes Mexican American women's current sedentary status by reviewing their physical activity history. Interventions aimed at promoting health in older adults require an understanding of the impact of prior experiences on current health behaviors. Thus, in-depth semistructured interviews were conducted with 71 Mexican American women (aged 50 years or older) recruited from local churches and senior centers. Household, occupational, and leisure activities from age 15 years to present time were reviewed. A lifelong pattern of low occupational and leisure activity and low to moderate household activity were found, with sedentary occupations and no leisure activities predominating. Most believed that current household, occupational and leisure activities provide enough physical activity, thus influencing participation in exercise programs or activities. Attempts to increase physical activity for this group need to begin by teaching them age-appropriate and culturally acceptable physical activities.

  3. 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.

  4. 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.

  5. 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

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

    PubMed

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

    2012-10-11

    The morphological 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 show 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.

  7. A combination of desmopressin and docetaxel inhibit cell proliferation and invasion mediated by urokinase-type plasminogen activator (uPA) in human prostate cancer cells

    SciTech Connect

    Sasaki, Hiroshi; Klotz, Laurence H.; Sugar, Linda M.; Kiss, Alexander; Venkateswaran, Vasundara

    2015-08-28

    Background: This study was designed to assess the effectiveness of a combination treatment using both desmopressin and docetaxel in prostate cancer treatment. Desmopressin is a well-known synthetic analogue of the antidiuretic hormone vasopressin. It has recently been demonstrated to inhibit tumor progression and metastasis in in vivo models. Docetaxel is widely used for the treatment of castration resistant prostate cancer (CRPC) patients. However, durable responses have been uncommon to date. In this study, we investigated the anti-tumor effect of desmopressin in combination with docetaxel in vitro and in vivo. Methods: Two prostate cancer cells (PC3, LNCaP) were treated with different concentrations of desmopressin alone, docetaxel alone, and a combination of desmopressin and docetaxel. Cell proliferation was determined by MTS assay. The anti-invasive and anti-migration potential of desmopressin and in combination with docetaxel were examined by wound healing assay, migration chamber assay, and matrigel invasion assay. Results: The combination of desmopressin and docetaxel resulted in a significant inhibition of PC3 and LNCaP cell proliferation (p < 0.01). Additionally, cell migration and invasion were also inhibited by the combination when compared to that of either treatment alone in PC3 cells (p < 0.01). The anti-tumor effect of this combination treatment was associated with down-regulation of both urokinase-type plasminogen activator (uPA) and matrix metalloproteinase (MMP-2 and MMP-9) in PC3 cells. Conclusions: We are the first to elucidate the anti-tumor and anti-metastatic potential of desmopressin in combination with docetaxel in a prostate cancer model via the uPA-MMP pathway. Our finding could potentially contribute to the therapeutic profile of desmopressin and enhance the efficacy of docetaxel based treatment for CRPC. - Highlights: • Desmopressin inhibits cell proliferation in prostate cancer cells. • The expression of cyclin A and CDK2

  8. 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…

  9. 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…

  10. Chewing pattern and muscular activation in open bite patients.

    PubMed

    Piancino, Maria Grazia; Isola, Gaetano; Merlo, Andrea; Dalessandri, Domenico; Debernardi, Cesare; Bracco, Pietro

    2012-04-01

    Different studies have indicated, in open bite patients, that masticatory muscles tend to generate a small maximum bite force and to show a reduced cross-sectional area with a lower EMG activity. The aim of this study was to evaluate the kinematics parameters of the chewing cycles and the activation of masseters and anterior temporalis muscles of patients with anterior dental open bite malocclusion. There have been no previous reports evaluating both kinematic values and EMG activity of patients with anterior open bite during chewing. Fifty-two young patients (23 boys and 29 girls; mean age±SD 11.5±1.2 and 10.2±1.6years, respectively) with anterior open bite malocclusion and 21 subjects with normal occlusion were selected for the study. Kinematics parameters and surface electromyography (EMG) were simultaneously recorded during chewing a hard bolus with a kinesiograph K7-I Myotronics-Usa. The results showed a statistically significant difference between the open bite patients and the control group for a narrower chewing pattern, a shorter total and closing duration of the chewing pattern, a lower peak of both the anterior temporalis and the masseter of the bolus side. In this study, it has been observed that open bite patients, lacking the inputs from the anterior guidance, that are considered important information for establishing the motor scheme of the chewing pattern, show narrower chewing pattern, shorter lasting chewing cycles and lower muscular activation with respect to the control group.

  11. How networks communicate: propagation patterns in spontaneous brain activity.

    PubMed

    Mitra, Anish; Raichle, Marcus E

    2016-10-05

    Initially regarded as 'noise', spontaneous (intrinsic) activity accounts for a large portion of the brain's metabolic cost. Moreover, it is now widely known that infra-slow (less than 0.1 Hz) spontaneous activity, measured using resting state functional magnetic resonance imaging of the blood oxygen level-dependent (BOLD) signal, is correlated within functionally defined resting state networks (RSNs). However, despite these advances, the temporal organization of spontaneous BOLD fluctuations has remained elusive. By studying temporal lags in the resting state BOLD signal, we have recently shown that spontaneous BOLD fluctuations consist of remarkably reproducible patterns of whole brain propagation. Embedded in these propagation patterns are unidirectional 'motifs' which, in turn, give rise to RSNs. Additionally, propagation patterns are markedly altered as a function of state, whether physiological or pathological. Understanding such propagation patterns will likely yield deeper insights into the role of spontaneous activity in brain function in health and disease.This article is part of the themed issue 'Interpreting blood oxygen level-dependent: a dialogue between cognitive and cellular neuroscience'.

  12. 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.

  13. 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.

  14. Reduction in ATP levels triggers immunoproteasome activation by the 11S (PA28) regulator during early antiviral response mediated by IFNβ in mouse pancreatic β-cells.

    PubMed

    Freudenburg, Wieke; Gautam, Madhav; Chakraborty, Pradipta; James, Jared; Richards, Jennifer; Salvatori, Alison S; Baldwin, Aaron; Schriewer, Jill; Buller, R Mark L; Corbett, John A; Skowyra, Dorota

    2013-01-01

    Autoimmune destruction of insulin producing pancreatic β-cells is the hallmark of type I diabetes. One of the key molecules implicated in the disease onset is the immunoproteasome, a protease with multiple proteolytic sites that collaborates with the constitutive 19S and the inducible 11S (PA28) activators to produce immunogenic peptides for presentation by MHC class I molecules. Despite its importance, little is known about the function and regulation of the immunoproteasome in pancreatic β-cells. Of special interest to immunoproteasome activation in β-cells are the effects of IFNβ, a type I IFN secreted by virus-infected cells and implicated in type I diabetes onset, compared to IFNγ, the classic immunoproteasome inducer secreted by cells of the immune system. By qPCR analysis, we show that mouse insulinoma MIN6 cells and mouse islets accumulate the immune proteolytic β1(i), β2(i) and β5(i), and 11S mRNAs upon exposure to IFNβ or IFNγ. Higher concentrations of IFNβ than IFNγ are needed for similar expression, but in each case the expression is transient, with maximal mRNA accumulation in 12 hours, and depends primarily on Interferon Regulatory Factor 1. IFNs do not alter expression of regular proteasome genes, and in the time frame of IFNβ-mediated response, the immune and regular proteolytic subunits co-exist in the 20S particles. In cell extracts with ATP, these particles have normal peptidase activities and degrade polyubiquitinated proteins with rates typical of the regular proteasome, implicating normal regulation by the 19S activator. However, ATP depletion rapidly stimulates the catalytic rates in a manner consistent with levels of the 11S activator. These findings suggest that stochastic combination of regular and immune proteolytic subunits may increase the probability with which unique immunogenic peptides are produced in pancreatic β-cells exposed to IFNβ, but primarily in cells with reduced ATP levels that stimulate the 11S

  15. 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.

  16. Physical activity patterns of youth with Down syndrome.

    PubMed

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

    2012-04-01

    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 were the most sedentary and spent the least amount of time in light and moderate-to-vigorous physical activity. A general trend of decreasing physical activity as children increase in age was found. This trend is similar to that found among typically developing youth. Participants in this study were found to spend a majority of their day engaged in sedentary activities. Results indicate that most participants were not accumulating the recommended 60 minutes of moderate or vigorous physical activity.

  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 PAGES

    Fairchild, Geoffrey; Hickmann, Kyle S.; Mniszewski, Susan 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. Tumour-associated urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1 in normal and neoplastic tissues of patients with squamous cell cancer of the oral cavity - clinical relevance and prognostic value.

    PubMed

    Hundsdorfer, Brigitte; Zeilhofer, Hans-Florian; Bock, Klaus Peter; Dettmar, Peer; Schmitt, Manfred; Kolk, Andreas; Pautke, Christoph; Horch, Hans-Henning

    2005-06-01

    The central role of the serine protease urokinase-type plasminogen activator (uPA) and its inhibitor, the plasminogen activator-inhibitor-1 (PAI-1), in tumour invasion and metastasis becomes more and more evident. In several studies, uPA and PAI-1 proved to be of prognostic relevance as shown for different types of cancer (e.g. breast, stomach, lung). Elevated antigen levels of uPA and/or PAI-1 predict poor outcome (relapse-free survival) for patients afflicted with cancer. For oral squamous cell carcinomas, however, the prognostic relevance of the tumour-associated proteolytic factors uPA and PAI-1 has still to be evaluated. In the present study, using tissue extracts of 79 oral cancer cases, 58 specimens of normal oral cavity mucosa and of 16 tumour positive lymph nodes taken from the same patients, uPA and PAI-1 antigen were determined by highly sensitive enzyme-linked immunosorbent assays (ELISA). A correlation was found between uPA and PAI-1 in tumour tissue, when compared with the normal mucosa of the same oral cavity. Median levels showed significant elevations in cancer tissue and in tumour positive lymph nodes versus normal oral mucosa. In patients with high levels of uPA or PAI-1, there were significantly more tumour relapses. There was no significant correlation between pathological TNM categories, grading, residual tumour category, tumour site and patient age. In summary, tumour uPA/PAI-1 content (as determined by ELISA) appears to be a strong independent prognostic factor for relapse-free survival in squamous cell cancer of the oral cavity. These observations might help to select patients with poor prognosis for additional adjuvant therapy in conjunction with complete surgical resection.

  20. Patterns of daily physical activity during school days in children and adolescents.

    PubMed

    Mota, Jorge; Santos, Paula; Guerra, Sandra; Ribeiro, José C; Duarte, José A

    2003-01-01

    The purpose of this study was to examine the weekday patterns of moderate-to-vigorous physical activity (MVPA) in school children and adolescents and determine if there are periods of the day that are representative of their typical MVPA. The sample comprised 84 subjects (boys, n = 30; girls, n = 54), age 8-15 years old. Daily totals for the physical activity variables were calculated by summing the values from 13 hr of physical activity (PA) measurements (9:00-22:00), with 60-min time blocks comprising each day. The MVPA data values were categorized in four daily periods: morning (9:00-11:59), noon (12:00-14:59), late afternoon (15:00-17.59), and evening (18:00-21.59). Our data show that boys participated significantly more in MVPA than girls. Despite no clear patterns or differences among sex being found, girls showed higher percent of time engaged in MVPA during the morning and early afternoon periods (sum of two periods 51.0%), while boys' percent of time engaged in MVPA is higher at late afternoon and evening periods (sum of two periods 53.8%). The principal components analyses showed four distinct components that accounted for 67% of the variance, as follows: school hours (component 1); lunchtime and outside-school activities (component 2); morning time before school period (component 4); and period before bedtime (component 3) appear as distinct periods of the day. In conclusion, the present study shows that boys engaged more in MVPA than girls. Girls tend to be more active during school periods, while boys are more active after school.

  1. 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

  2. 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.

  3. 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.

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

    PubMed

    Macho, Alberto P; Schwessinger, Benjamin; Ntoukakis, Vardis; Brutus, Alexandre; Segonzac, Cécile; Roy, Sonali; Kadota, Yasuhiro; Oh, Man-Ho; Sklenar, Jan; Derbyshire, Paul; Lozano-Durán, Rosa; Malinovsky, Frederikke Gro; Monaghan, Jacqueline; Menke, Frank L; Huber, Steven C; He, Sheng Yang; Zipfel, Cyril

    2014-03-28

    Innate immunity relies on the perception of pathogen-associated molecular patterns (PAMPs) by pattern-recognition receptors (PRRs) located on the host cell's surface. Many plant PRRs are kinases. Here, we report that the Arabidopsis receptor kinase EF-TU RECEPTOR (EFR), which perceives the elf18 peptide derived from bacterial elongation factor Tu, is activated upon ligand binding by phosphorylation on its tyrosine residues. Phosphorylation of a single tyrosine residue, Y836, is required for activation of EFR and downstream immunity to the phytopathogenic bacterium Pseudomonas syringae. A tyrosine phosphatase, HopAO1, secreted by P. syringae, reduces EFR phosphorylation and prevents subsequent immune responses. Thus, host and pathogen compete to take control of PRR tyrosine phosphorylation used to initiate antibacterial immunity.

  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. Degradation of Internalized αvβ5 Integrin Is Controlled by uPAR Bound uPA: Effect on β1 Integrin Activity and α-SMA Stress Fiber Assembly

    PubMed Central

    Wang, Lingyan; Pedroja, Benjamin S.; Meyers, Erin E.; Garcia, Angelo L.; Twining, Sally S.; Bernstein, Audrey M.

    2012-01-01

    Myofibroblasts (Mfs) that persist in a healing wound promote extracellular matrix (ECM) accumulation and excessive tissue contraction. Increased levels of integrin αvβ5 promote the Mf phenotype and other fibrotic markers. Previously we reported that maintaining uPA (urokinase plasminogen activator) bound to its cell-surface receptor, uPAR prevented TGFβ-induced Mf differentiation. We now demonstrate that uPA/uPAR controls integrin β5 protein levels and in turn, the Mf phenotype. When cell-surface uPA was increased, integrin β5 levels were reduced (61%). In contrast, when uPA/uPAR was silenced, integrin β5 total and cell-surface levels were increased (2–4 fold). Integrin β5 accumulation resulted from a significant decrease in β5 ubiquitination leading to a decrease in the degradation rate of internalized β5. uPA-silencing also induced α-SMA stress fiber organization in cells that were seeded on collagen, increased cell area (1.7 fold), and increased integrin β1 binding to the collagen matrix, with reduced activation of β1. Elevated cell-surface integrin β5 was necessary for these changes after uPA-silencing since blocking αvβ5 function reversed these effects. Our data support a novel mechanism by which downregulation of uPA/uPAR results in increased integrin αvβ5 cell-surface protein levels that regulate the activity of β1 integrins, promoting characteristics of the persistent Mf. PMID:22470492

  7. Patterns of Adolescent Physical Activity, Screen-Based Media Use and Positive and Negative Health Indicators in the U.S. and Canada

    PubMed Central

    Iannotti, Ronald J.; Kogan, Michael D.; Janssen, Ian; Boyce, William F.

    2008-01-01

    Purpose To examine: 1) how adolescent physical activity (PA) and screen-based media use (SBM) relate to physical and social health indicators, and 2) cross-national differences in these relationships. Methods Essentially identical questions and methodologies were used in the Health Behavior in School-Aged Children cross-sectional surveys of nationally-representative samples of American (N = 14,818) and Canadian (N = 7,266) students in grades 6 to 10. Items included questions about frequency of PA, SBM, positive health indicators (health status, self-image, quality of life, and quality of family and peer relationships), and negative health indicators (health complaints, physical aggression, smoking, drinking, and marijuana use). Results In regression analyses controlling for age and gender, positive health indicators were uniformly positively related to PA while two negative health indicators were negatively related to PA. However, PA was positively related to physical aggression. The pattern for SBM was generally the opposite; SBM was negatively related to most positive health indices and positively related to several of the negative health indicators. The notable exception was that SBM was positively related to the quality of peer relationships. Although there were cross-national differences in the strength of some relationships, these patterns were essentially replicated in both countries. Conclusions Surveys of nationally representative samples of youth in two countries provide evidence of positive physical and social concomitants of PA and negative concomitants of SBM. These findings suggest potential positive consequences of increasing PA and decreasing SBM in adolescents and provide further justification for such efforts. PMID:19380098

  8. 32 CFR 701.123 - PA fees.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... duplication for free. (1) DON activities shall waive fees automatically if the direct cost for reproduction of... made on a case-to-case basis. (c) PA fee deposits. Checks or money orders shall be made payable to...

  9. A higher body temperature is associated with haemorrhagic transformation in patients with acute stroke untreated with recombinant tissue-type plasminogen activator (rtPA).

    PubMed

    Leira, Rogelio; Sobrino, Tomás; Blanco, Miguel; Campos, Francisco; Rodríguez-Yáñez, Manuel; Castellanos, Mar; Moldes, Octavio; Millán, Mónica; Dávalos, Antoni; Castillo, José

    2012-02-01

    Higher body temperature is a prognostic factor of poor outcome in acute stroke. Our aim was to study the relationship between body temperature, HT (haemorrhagic transformation) and biomarkers of BBB (blood-brain barrier) damage in patients with acute ischaemic stroke untreated with rtPA (recombinant tissue-type plasminogen activator). We studied 229 patients with ischaemic stroke <12 h from symptom onset. Body temperature was determined at admission and every 6 h during the first 3 days. HT was evaluated according to ECASS II (second European Co-operative Acute Stroke Study) criteria in a multimodal MRI (magnetic resonance imaging) at 72 h. We found that 55 patients (34.1%) showed HT. HT was associated with cardioembolic stroke (64.2% against 23.0%; P<0.0001), higher body temperature during the first 24 h (36.9°C compared with 36.5°C; P<0.0001), more severe stroke [NIHSS (National Institutes of Health Stroke Scale) score, 14 (9-20) against 10 (7-15); P=0.002], and greater DWI (diffusion-weighted imaging) lesion volume at admission (23.2 cc compared with 13.2 cc; P<0.0001). Plasma MMP-9 (matrix metalloproteinase 9) (187.3 ng/ml compared with 44.2 ng/ml; P<0.0001) and cFn (cellular fibronectin) levels (16.3 μg/ml compared with 7.1 μg/ml; P=0.001) were higher in patients with HT. Body temperature within the first 24 h was independently associated with HT {OR (odds ratio), 7.3 [95% CI (confidence interval), 2.4-22.6]; P<0.0001} after adjustment for cardioembolic stroke subtype, baseline NIHSS score and DWI lesion volume. This effect remained unchanged after controlling for MMP-9 and cFn. In conclusion, high body temperature within the first 24 h after ischaemic stroke is a risk factor for HT in patients untreated with rtPA. This effect is independent of some biological signatures of BBB damage.

  10. Automatic Camera Calibration Using Active Displays of a Virtual Pattern.

    PubMed

    Tan, Lei; Wang, Yaonan; Yu, Hongshan; Zhu, Jiang

    2017-03-27

    Camera calibration plays a critical role in 3D computer vision tasks. The most commonly used calibration method utilizes a planar checkerboard and can be done nearly fully automatically. However, it requires the user to move either the camera or the checkerboard during the capture step. This manual operation is time consuming and makes the calibration results unstable. In order to solve the above problems caused by manual operation, this paper presents a full-automatic camera calibration method using a virtual pattern instead of a physical one. The virtual pattern is actively transformed and displayed on a screen so that the control points of the pattern can be uniformly observed in the camera view. The proposed method estimates the camera parameters from point correspondences between 2D image points and the virtual pattern. The camera and the screen are fixed during the whole process; therefore, the proposed method does not require any manual operations. Performance of the proposed method is evaluated through experiments on both synthetic and real data. Experimental results show that the proposed method can achieve stable results and its accuracy is comparable to the standard method by Zhang.

  11. PA Discussion Topics

    DTIC Science & Technology

    2011-02-04

    Vehicle Power & Mobility PA Discussion Topics UNCLASSIFIED: Dist A. Approved for public releas Report Documentation Page Form ApprovedOMB No. 0704...0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions...Headquarters Services, Directorate for Information Operations and Reports , 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302

  12. 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.

  13. Activity pattern of selected ungulates at Krau Wildlife Reserve

    NASA Astrophysics Data System (ADS)

    Sanusi, M. A. Mohd; Shukor, M. A.; Juliana, W. A. Wan; Traeholt, C.

    2013-11-01

    The study on ecology and feeding behaviour of selected wildlife species was carried out at the Krau Wildlife Reserve (KWR), Pahang. We aim to identify the wildlife species that present at KWR using camera traps, determine activity pattern ofungulates and study the feeding behaviour of selected herbivores including foraging time, method or behaviours and other individuals that are present during feeding. Camera trap data revealed a total of 19 wildlife species inhabiting the forest areas which include three species of ungulates namely Tapirus indicus, Sus scrofa and Muntiacus muntjak. The T. indicus was actively feeding between 2300 and 0500 hours, S. scrofa between 0600 and 1800 hours while M. muntjack 0600 and 1700 hours. Activity pattern of three ungulate species indicated that T. indicus is nocturnal, M. muntjak is diurnal and S. scrofais active both day and night. Each of the animal species inhabiting the study sites are able to compromise and did not compete among each other by foraging at different time and food resources.

  14. Extracellular stimulation with human "noisy" electromyographic patterns facilitates myotube activity.

    PubMed

    Sciancalepore, M; Coslovich, T; Lorenzon, P; Ziraldo, G; Taccola, G

    2015-10-01

    Electrical stimulation (ES) of skeletal muscle partially mimics the benefits of physical activity. However, the stimulation protocols applied clinically to date, often cause unpleasant symptoms and muscle fatigue. Here, we compared the efficiency of a "noisy" stimulus waveform derived from human electromyographic (EMG) muscle patterns, with stereotyped 45 and 1 Hz electrical stimulations applied to mouse myotubes in vitro. Human gastrocnemius medialis electromyograms recorded from volunteers during real locomotor activity were used as a template for a noisy stimulation, called EMGstim. The stimulus-induced electrical activity, intracellular Ca(2+) dynamics and mechanical twitches in the myotubes were assessed using whole-cell perforated patch-clamp, Ca(2+) imaging and optical visualization techniques. EMGstim was more efficient in inducing myotube cell firing, [Ca(2+)]i changes and contractions compared with more conventional electrical stimulation. Its stimulation strength was also much lower than the minimum required to induce contractions via stereotyped stimulation protocols. We conclude that muscle cells in vitro can be more efficiently depolarized using the "noisy" stochastic stimulation pattern, EMGstim, a finding that suggests a way to favor a higher level of electrical activity in a larger number of cells.

  15. 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.

  16. 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.

  17. 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.

  18. Patterns of Spontaneous Magnetoencephalographic Activity in Schizophrenic Patients

    PubMed Central

    Siekmeier, Peter J.; Stufflebeam, Steven M.

    2010-01-01

    Magnetoencephalography (MEG) non-invasively measures the magnetic fields produced by the brain. Pertinent research articles from 1993 to 2009 that measured spontaneous, whole-head MEG activity in schizophrenic patients were reviewed. Data on localization of oscillatory activity and correlation of these findings with psychotic symptoms are summarized. While the variety of measures used by different research groups makes a quantitative meta-analysis difficult, it appears that MEG activity in patients may exhibit identifiable patterns, defined by topographic organization and frequency band. Specifically, 11 of the 12 studies showed increased theta (4–8 Hz) and delta (1–4 Hz) band oscillations in the temporal lobes of patients; of the 10 studies that examined the relationship between oscillatory activity and symptomatology, 8 found a positive correlation between temporal lobe theta activity and positive schizophrenic symptoms. Abnormally high frontal delta activity was not seen. These findings are analyzed in comparison to the EEG literature on schizophrenics, and possible confounds (e.g., medication effects) are discussed. In the future, MEG might be used to assist in diagnosis, or might be fruitfully used in conjunction with new neuroscience research approaches such as computational modeling, which may be able to link oscillatory activity and cellular-level pathology. PMID:20461010

  19. Patterns of spontaneous magnetoencephalographic activity in patients with schizophrenia.

    PubMed

    Siekmeier, Peter J; Stufflebeam, Steven M

    2010-06-01

    Magnetoencephalography noninvasively measures the magnetic fields produced by the brain. Pertinent research articles from 1993 to 2009 that measured spontaneous, whole-head magnetoencephalography activity in patients with schizophrenia were reviewed. Data on localization of oscillatory activity and correlation of these findings with psychotic symptoms are summarized. Although the variety of measures used by different research groups makes a quantitative meta-analysis difficult, it appears that magnetoencephalography activity in patients may exhibit identifiable patterns, defined by topographic organization and frequency band. Specifically, 11 of the 12 studies showed increased theta (4-8 Hz) and delta (1-4 Hz) band oscillations in the temporal lobes of patients; of the 10 studies that examined the relationship between oscillatory activity and symptomatology, 8 found a positive correlation between temporal lobe theta activity and positive schizophrenic symptoms. Abnormally high frontal delta activity was not seen. These findings are analyzed in comparison with the electroencephalogram literature on schizophrenics, and possible confounds (e.g., medication effects) are discussed. In the future, magnetoencephalography might be used to assist in diagnosis or might be fruitfully used in conjunction with new neuroscience research approaches such as computational modeling, which may be able to link oscillatory activity and cellular-level pathology.

  20. 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.

  1. The concentration of criminal victimization and patterns of routine activities.

    PubMed

    Kuo, Shih-Ya; Cuvelier, Steven J; Sheu, Chuen-Jim; Zhao, Jihong Solomon

    2012-06-01

    Although many repeat victimization studies have focused on describing the prevalence of the phenomenon, this study attempted to explain variations in the concentration of victimization by applying routine activities as a theoretical model. A multivariate analysis of repeat victimization based on the 2005 Taiwan criminal victimization data supported the general applicability of the routine activity model developed in Western culture for predicting repeat victimization. Findings that diverged from Western patterns included family income to assault, gender to robbery, and marital status, family income, and major activity to larceny incidents. These disparities illustrated the importance of considering the broader sociocultural context in the association between risk predictors and the concentration of criminal victimization. The contradictory results and nonsignificant variance also reflected untapped information on respondents' biological features and psychological tendencies. Future victimization research would do well to integrate measurements that are sensitive to salient sociocultural elements of the society being studied and individuals' biological and psychological traits.

  2. Activity patterns of serotonin neurons underlying cognitive flexibility.

    PubMed

    Matias, Sara; Lottem, Eran; Dugué, Guillaume P; Mainen, Zachary F

    2017-03-21

    Serotonin is implicated in mood and affective disorders. However, growing evidence suggests that a core endogenous role is to promote flexible adaptation to changes in the causal structure of the environment, through behavioral inhibition and enhanced plasticity. We used long-term photometric recordings in mice to study a population of dorsal raphe serotonin neurons, whose activity we could link to normal reversal learning using pharmacogenetics. We found that these neurons are activated by both positive and negative prediction errors, and thus report signals similar to those proposed to promote learning in conditions of uncertainty. Furthermore, by comparing the cue responses of serotonin and dopamine neurons, we found differences in learning rates that could explain the importance of serotonin in inhibiting perseverative responding. Our findings show how the activity patterns of serotonin neurons support a role in cognitive flexibility, and suggest a revised model of dopamine-serotonin opponency with potential clinical implications.

  3. 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

  4. 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.

  5. 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

  6. Pattern matching based active optical sorting of colloids/cells

    NASA Astrophysics Data System (ADS)

    Verma, R. S.; Dasgupta, R.; Ahlawat, S.; Kumar, N.; Uppal, A.; Gupta, P. K.

    2013-08-01

    We report active optical sorting of colloids/cells by employing a cross correlation based pattern matching technique for selection of the desired objects and thereafter sorting using dynamically controllable holographic optical traps. The problem of possible collision between the different sets of objects during sorting was avoided by raising one set of particles to a different plane. We also present the results obtained on using this approach for some representative applications such as sorting of silica particles of two different sizes, of closely packed colloids and of white blood cells and red blood cells from a mixture of the two.

  7. Zinc supplementation affects the activity patterns of rural Guatemalan infants.

    PubMed

    Bentley, M E; Caulfield, L E; Ram, M; Santizo, M C; Hurtado, E; Rivera, J A; Ruel, M T; Brown, K H

    1997-07-01

    Zinc deficiency has been associated with growth deficits, reduced dietary intake and appetite, and has been hypothesized to result in reduced activity. This randomized, double-blind, placebo-controlled study examined whether 10 mg of oral zinc as zinc sulfate, given daily for up to 7 mo, affected activity patterns of 85 Guatemalan infants recruited at 6-9 mo of age. Infant activity was assessed by time sampling-observation method at 10-min intervals during a 12-h data collection period, at base line, 3 and 7 mo follow-up. Motor development and the percentage of time infants were observed in various positions (being carried, lying down, sitting, crawling, standing or walking) and engaged in various activities (eating, sleeping, resting, crying/whining or playing) were compared by treatment group. No differences in motor development were observed by treatment group. However, at follow-up 2 (after 7 mo of supplementation), zinc-supplemented infants were significantly more frequently observed sitting up compared with lying down, and were playing during 4.18 +/- 1.95% (P < 0.05) more observations than unsupplemented infants. They were also somewhat less likely to be observed crying or whining (P < 0.10) compared with those receiving the placebo. These effects are independent of other factors including infant age, motor development, sex, maternal education, family socioeconomic status and nutritional status at base line. Further research must be conducted to determine the long-term developmental importance of these differences in activity patterns associated with zinc supplementation in this setting.

  8. 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…

  9. 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.

  10. 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

  11. Veno-occlusive disease (VOD) of the liver in Korean patients following allogeneic bone marrow transplantation (BMT): efficacy of recombinant human tissue plasminogen activator (rt-PA) treatment.

    PubMed

    Lee, J H; Lee, K H; Choi, J S; Zang, D Y; Kim, S B; Kim, S W; Suh, C; Lee, J S; Kim, W K; Lee, Y S; Kim, S H

    1996-04-01

    Veno-occlusive disease (VOD) of the liver is a clinical syndrome characterized by hyperbilirubinemia, painful hepatomegaly, and fluid retention. In the bone marrow transplantation (BMT) setting, VOD is caused by dose-intensive chemotherapy and/or radiotherapy used to prepare patients for transplant. VOD occurs in up to 50% of the patients who undergo BMT and is usually associated with a high mortality rate. Until recently, there was no proven effective medical therapy for this condition once it was clinically apparent. We report here on the frequency and treatment result of VOD with rt-PA in our allogeneic BMT patients. Eight patients (median age 28.5 years) underwent allogeneic BMT from December, 1993 to June, 1995 in Asan Medical Center. Six leukemia patients were prepared for BMT with busulfan and cyclophosphmide, while two aplastic anemia patients received cyclophosphamide and antithymocyte globulin. VOD was defined as having two of the following features before day 20 posttransplant: jaundice (bilirubin > or = 2 mg/dL), tender hepatomegaly and/or right upper quadrant pain, ascites and/or unexplained weight gain (> 2% from baseline). All patients who were diagnosed with VOD received rt-PA (10-20 mg/day) and heparin (10,000 U/day). Three (37.5%) of the eight patients developed VOD that occurred between 6 and 10 days posttransplant. All three patients developed jaundice, weight gain, and tender hepatomegaly. Ascites and renal insufficiency occurred in two patients and pleural effusion in one patient. rt-PA and heparin were begun 6 to 26 days posttransplant and rt-PA was administered for 7 to 14 days. All three patients responded to the therapy; bilirubin levels began to decrease at 4 to 13 days from the start of therapy. They are all alive at day 111, 316, and 548 days posttransplant. None of the patients had significant hemorrhagic complications after rt-PA treatment. Prolonged administration of rt-PA was feasible without bleeding episode and it seems that rt-PA

  12. 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

  13. Patterns of leisure time and non-leisure time physical activity of Korean immigrant women.

    PubMed

    Choi, Jiwon; Wilbur, Joellen; Kim, Mi Ja

    2011-02-01

    Our purpose in this study was to examine the patterns of physical activity and demographic characteristics associated with those patterns in Korean immigrants in the United States. Participants were 197 women, and the International Physical Activity Questionnaire was utilized. The inactive pattern was the most frequent pattern in all domains of physical activity except household physical activity. There were differences among the patterns of physical activity that were associated with variations in demographic characteristics. Health care providers who serve immigrants should assess physical activity level and demographic characteristics of the immigrants to enhance their physical activity.

  14. PATTERNS OF ACTIVITY IN A GLOBAL MODEL OF A SOLAR ACTIVE REGION

    SciTech Connect

    Bradshaw, S. J.; Viall, N. M. E-mail: Nicholeen.M.Viall@nasa.gov

    2016-04-10

    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.

  15. Activity patterns of serotonin neurons underlying cognitive flexibility

    PubMed Central

    Matias, Sara; Lottem, Eran; Dugué, Guillaume P; Mainen, Zachary F

    2017-01-01

    Serotonin is implicated in mood and affective disorders. However, growing evidence suggests that a core endogenous role is to promote flexible adaptation to changes in the causal structure of the environment, through behavioral inhibition and enhanced plasticity. We used long-term photometric recordings in mice to study a population of dorsal raphe serotonin neurons, whose activity we could link to normal reversal learning using pharmacogenetics. We found that these neurons are activated by both positive and negative prediction errors, and thus report signals similar to those proposed to promote learning in conditions of uncertainty. Furthermore, by comparing the cue responses of serotonin and dopamine neurons, we found differences in learning rates that could explain the importance of serotonin in inhibiting perseverative responding. Our findings show how the activity patterns of serotonin neurons support a role in cognitive flexibility, and suggest a revised model of dopamine–serotonin opponency with potential clinical implications. DOI: http://dx.doi.org/10.7554/eLife.20552.001 PMID:28322190

  16. Muscular activation patterns of the bow arm in recurve archery.

    PubMed

    Ertan, Hayri

    2009-05-01

    In archery shooting, the archer should hold the bow in place using only the pressure produced through drawing back the bowstring. Most coaches discourage the archer from gripping the bow as this is believed to produce a sideways deflecting torque on the bow and arrow during the release. The purpose of this study was to compare the bow hand forearm muscular activation patterns of elite archers with beginners to define the muscular contraction-relaxation strategies in the bow hand forearm muscles during archery shooting and investigate the effects of performance level on these strategies. Electromyographic activity of the M. flexor digitorum superficialis and the M. extensor digitorum of 10 elite and 10 beginner archers were recorded together with a pulse synchronized with the clicker snap. Raw electromyographic records as 1s before and after the clicker pulse were rectified, integrated, and normalized. The data was then averaged for successive shots of each subject and later for both groups of archers. The main difference between the elite and beginner archers was that the elite archers had a greater activation of the M. extensor digitorum, which indicates that they avoid gripping the bow-handle not only relaxing the flexor muscles, but also contracting the extensor muscle groups. This muscular contraction strategy secures the archer to not interfere with the forward movement of the bow, which is the forward acceleration of the bow caused by the pushing power of the bowstring.

  17. 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

  18. 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.

  19. Command of active matter by topological defects and patterns

    NASA Astrophysics Data System (ADS)

    Peng, Chenhui; Turiv, Taras; Guo, Yubing; Wei, Qi-Huo; Lavrentovich, Oleg D.

    2016-11-01

    Self-propelled bacteria are marvels of nature with a potential to power dynamic materials and microsystems of the future. The challenge lies in commanding their chaotic behavior. By dispersing swimming Bacillus subtilis in a liquid crystalline environment with spatially varying orientation of the anisotropy axis, we demonstrate control over the distribution of bacterial concentration, as well as the geometry and polarity of their trajectories. Bacteria recognize subtle differences in liquid crystal deformations, engaging in bipolar swimming in regions of pure splay and bend but switching to unipolar swimming in mixed splay-bend regions. They differentiate topological defects, heading toward defects of positive topological charge and avoiding negative charges. Sensitivity of bacteria to preimposed orientational patterns represents a previously unknown facet of the interplay between hydrodynamics and topology of active matter.

  20. Natural patterns of activity and long-term synaptic plasticity

    PubMed Central

    Paulsen, Ole; Sejnowski, Terrence J

    2010-01-01

    Long-term potentiation (LTP) of synaptic transmission is traditionally elicited by massively synchronous, high-frequency inputs, which rarely occur naturally. Recent in vitro experiments have revealed that both LTP and long-term depression (LTD) can arise by appropriately pairing weak synaptic inputs with action potentials in the postsynaptic cell. This discovery has generated new insights into the conditions under which synaptic modification may occur in pyramidal neurons in vivo. First, it has been shown that the temporal order of the synaptic input and the postsynaptic spike within a narrow temporal window determines whether LTP or LTD is elicited, according to a temporally asymmetric Hebbian learning rule. Second, backpropagating action potentials are able to serve as a global signal for synaptic plasticity in a neuron compared with local associative interactions between synaptic inputs on dendrites. Third, a specific temporal pattern of activity — postsynaptic bursting — accompanies synaptic potentiation in adults. PMID:10753798

  1. How family support affects physical activity (PA) among middle-aged and elderly people before and after they suffer from chronic diseases.

    PubMed

    Yuan, Su-Chuan; Weng, Shuo-Chun; Chou, Ming-Chih; Tang, Yih-Jing; Lee, Shu-Hsin; Chen, Der-Yuan; Chuang, Ya-Wen; Yu, Chia-Hui; Kuo, Hsien-Wen

    2011-01-01

    The more support elderly people have from their family, the less likely they are to suffer from chronic diseases. The objective of this study is to investigate how family support affects the PA middle-aged and elderly people engage in before and after they suffer from chronic diseases. We interviewed 428 middle-aged and elderly people using a structured questionnaire to measure their aerobic PA. Eighteen percent of middle-aged and elderly people did participate in PA after suffering from chronic diseases. Using multivariate logistic regression models, we found that middle-aged and elderly people who rely on family members when they are sick (OR=1.87, 95%CI=1.08-3.25) and who are accompanied by family members (OR=2.09, 95%CI=1.20-3.62) when they are healthy are more likely to exercise. The more middle-aged and elderly people are supported by their family, the more likely they are to exercise. Strengthening family relationships should help reduce the prevalence of chronic diseases among middle-aged and elderly people.

  2. Role of the lid hydrophobicity pattern in pancreatic lipase activity.

    PubMed

    Thomas, Annick; Allouche, Maya; Basyn, Frédéric; Brasseur, Robert; Kerfelec, Brigitte

    2005-12-02

    Pancreatic lipase is a soluble globular protein that must undergo structural modifications before it can hydrolyze oil droplets coated with bile salts. The binding of colipase and movement of the lipase lid open access to the active site. Mechanisms triggering lid mobility are unclear. The *KNILSQIVDIDGI* fragment of the lid of the human pancreatic lipase is predicted by molecular modeling to be a tilted peptide. Tilted peptides are hydrophobicity motifs involved in membrane fusion and more globally in perturbations of hydrophobic/hydrophilic interfaces. Analysis of this lid fragment predicts no clear consensus of secondary structure that suggests that its structure is not strongly sequence determined and could vary with environment. Point mutations were designed to modify the hydrophobicity profile of the [240-252] fragment and their consequences on the lipase-mediated catalysis were tested. Two mutants, in which the tilted peptide motif was lost, also have poor activity on bile salt-coated oil droplets and cannot be reactivated by colipase. Conversely, one mutant in which a different tilted peptide is created retains colipase dependence. These results suggest that the tilted hydrophobicity pattern of the [240-252] fragment is neither important for colipase binding to lipase, nor for interfacial binding but is important to trigger the maximal catalytic efficiency of lipase in the presence of bile salt.

  3. 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

  4. 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.

  5. Expression patterns of sirtuin genes in porcine preimplantation embryos and effects of sirtuin inhibitors on in vitro embryonic development after parthenogenetic activation and in vitro fertilization.

    PubMed

    Kwak, Seong-Sung; Cheong, Seung-A; Yoon, Junchul David; Jeon, Yubyeol; Hyun, Sang-Hwan

    2012-10-15

    We examined the expression patterns of porcine sirtuin 1 to 3 (Sirt1-3) genes in preimplantation embryos derived from parthenogenetic activation (PA), in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT). We also investigated the effects of sirtuin inhibitors (5 mM nicotinamide [NAM] and 100 μM sirtinol) on embryonic development of PA and IVF embryos under in vitro culture (IVC). The expression patterns of Sirt1-3 mRNA in preimplantation embryos of PA, IVF, and SCNT were significantly (P < 0.05) decreased from metaphase stage of oocyte to blastocyst stage. Especially, the expressions of Sirt1-3 in SCNT blastocysts were significantly (P < 0.05) lower and Sirt2 in PA blastocyst was significantly higher compared with the IVF blastocysts. Treatment with sirtuin inhibitors during IVC resulted in significantly (P < 0.05) decreased blastocyst formation and total cell number of blastocyst derived from PA (NAM: 29.4% and 29.6, sirtinol: 31.0% and 30.3, and control: 40.9% and 41.7, respectively) and IVF embryos (NAM: 10.4% and 30.9, sirtinol: 6.3% and 30.5, and control: 16.7% and 42.8, respectively). There was no significant difference in cleavage rate in both PA and IVF embryos. The early and expanded blastocyst formations at Day 7 were significantly lower in the sirtuin inhibitors-treated groups than the control. It was demonstrated that sirtuin inhibitor (NAM) influenced the percentage of blastocyst formation and total cell number of PA derived blastocyst when NAM was added during day 4 to 7 (22.1% and 32.4) or day 0 to 7 (23.1% and 31.6) of IVC compared with the control (41.8% and 41.5). No significant difference in cleavage rates appeared among the groups. The blastocysts derived from PA embryos treated with sirtuin inhibitors showed lower (P < 0.05) expressions of POU5F1 and Cdx2 genes. Also, Sirt2 mRNA expression was significantly decreased in sirtinol treated group and Sirt3 mRNA expression was also significantly decreased in both NAM and sirtinol

  6. Melatonin induces cell apoptosis in Mia PaCa-2 cells via the suppression of nuclear factor-κB and activation of ERK and JNK: A novel therapeutic implication for pancreatic cancer.

    PubMed

    Li, Weimin; Wu, Jiansheng; Li, Zhiyin; Zhou, Zhibo; Zheng, Chao; Lin, Le; Tan, Binbin; Huang, Min; Fan, Mengdi

    2016-11-01

    Melatonin is synthesized by the pineal gland and is released into the blood. In the last several years, some studies have shown that melatonin has anticancer properties; however, the mechanisms behind the antitumour traits are unclear, especially in pancreatic cancer. Therefore, in the present study, we investigated the antitumour effects of melatonin on the human pancreatic carcinoma cell line MIA PaCa‑2 and explored its biological mechanisms. MIA PaCa‑2 cells were treated with melatonin, and we used a CCK‑8 assay to evaluate the cell viability. We also used flow cytometry to observe cell apoptosis and western blot analysis to assess the protein expression. Our study found that melatonin inhibited cell viability, suppressed colony formation and reduced cell migration and invasion and induced cell apoptosis in MIA PaCa‑2 cells. Our results showed that melatonin treatment inhibited NF‑κB p65 activation. Moreover, melatonin treatment activated the mitogen‑activated protein kinase pathways (c‑jun N‑terminal kinase and extracellular‑regulated kinase 1/2), which increased Bax protein expression and caspase‑3 cleavage and decreased Bcl‑2 protein expression. These new developments demonstrate that melatonin plays a potential role in anticancer treatment and may act as an effective therapeutic agent in the future.

  7. Physical Activity Patterns of the Spanish Population Are Mostly Determined by Sex and Age: Findings in the ANIBES Study

    PubMed Central

    Mielgo-Ayuso, Juan; Aparicio-Ugarriza, Raquel; Castillo, Adrián; Ruiz, Emma; Ávila, José Manuel; Aranceta-Batrina, Javier; Gil, Ángel; Ortega, Rosa M.; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; González-Gross, Marcela

    2016-01-01

    Background Representative data for the Spanish population regarding physical activity (PA) behaviors are scarce and seldom comparable due to methodological inconsistencies. Aim Our objectives were to describe the PA behavior by means of the standardized self-reported International Physical Activity Questionnaire (IPAQ) and to know the proportion of the Spanish population meeting and not meeting international PA recommendations. Material and Methods PA was assessed using the IPAQ in a representative sample of 2285 individuals (males, 50.4%) aged 9–75 years and living in municipalities of at least 2,000 inhabitants. Data were analyzed according to: age groups 9–12, 13–17, 18–64, and 65–75 years; sex; geographical distribution; locality size and educational levels. Results Mean total PA was 868.8±660.9 min/wk, mean vigorous PA 146.4±254.1 min/wk, and mean moderate PA 398.1±408.0 min/wk, showing significant differences between sexes (p<0.05). Children performed higher moderate-vigorous PA than adolescents and seniors (p<0.05), and adults than adolescents and seniors (p<0.05). Compared to recommendations, 36.2% of adults performed <150 min/week of moderate PA, 65.4% <75 min/week of vigorous PA and 27.0% did not perform any PA at all, presenting significant differences between sexes (p<0.05). A total of 55.4% of children and adolescents performed less than 420 min/week of MVPA, being higher in the later (62.6%) than in the former (48.4%). Highest non-compliance was observed in adolescent females (86.5%). Conclusion Sex and age are the main influencing factors on PA in the Spanish population. Males engage in more vigorous and light PA overall, whereas females perform more moderate PA. PA behavior differs between age groups and no clear lineal increase with age could be observed. Twenty-seven percent of adults and 55.4% of children and adolescents do not meet international PA recommendations. Identified target groups should be addressed to increase PA in the

  8. 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.

  9. Early patterns of sexual activity: age cohort differences in Australia.

    PubMed

    Boyle, Frances M; Dunne, Michael P; Purdie, David M; Najman, Jake M; Cook, Michele D

    2003-11-01

    Patterns of first sexual activity among Australians born between the 1940s and 1980s were analysed using data from a national telephone survey of 1784 adults (876 males; 908 females). Sixty-one percent of those randomly selected from the Australian electoral roll and contactable by telephone responded. Many trends, including earlier first intercourse--from 20 to 18 years (females) and 18.8 to 17.8 years (males)--were established with the 40-49 year cohort, whose sexual debut was in the late 1960s-70s. Significant age-cohort effects saw women in the contemporary (18-29 year) cohort draw level with males for age at first intercourse and first sex before age 16 and before leaving school. First intercourse contraceptive use climbed from 30% to 80%. Condom use quadrupled to 70%. Australian age-cohort effects are remarkably consistent with those in similar western cultures: gender convergence in sexual experience and increasing avoidance of sexually transmitted disease and pregnancy. If such trends continue, positive long-term outcomes for health and social wellbeing should result.

  10. An integrative framework of the skin receptors activation: mechanoreceptors activity patterns versus "labeled lines".

    PubMed

    Zeveke, Alexander V; Efes, Ekaterina D; Polevaya, Sofia A

    2013-03-01

    The paper presents a review of electrophysiological data which indicate the integrative mechanisms of information coded in the human and animal peripheral skin receptors. The activity of the skin sensory receptors was examined by applying various natural stimuli. It was revealed that numerous identical receptors respond to various stimuli (mechanical, temperature, and pain ones), but the spike patterns of these receptors were found to be specific for each stimulus. The description of characteristic structures of spike patterns in the cutaneous nerve fibers in response to five major modalities, namely: "touch", "pain", "vibration/breath", "cold", and "heat", is being presented. The recordings of the cutaneous physical state revealed a correlation between the patterns of spatiotemporal skin deformation and the receptors activity. A rheological state of the skin can be changed either in response to external temperature variation or by the sympathetic pilomotor activation. These results indicate that the skin sensory receptors activity may be considered as an integrative process. It depends not only on the receptors themselves, but also on the changes in the surrounding tissue and on the adaptive influence of the central nervous system. A new framework for the sensory channel system related to the skin is proposed on the basis of experimental results.

  11. 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...

  12. H-bonded supramolecular assembly via proton transfer: Isolation, X-ray crystallographic characterization and SOD mimic activity of [Cu(dipic)2]2[PA-H]4·5H2O

    NASA Astrophysics Data System (ADS)

    Siddiqi, Zafar A.; Khalid, Mohd; Shahid, M.; Kumar, Sarvendra; Sharma, Prashant K.; Siddique, Armeen; Anjuli

    2013-02-01

    The title proton transfer complex was isolated from the reaction of CuCl2·2H2O with pyridine-2,6-dicarboxylic acid (dipic-H2) in presence of 3-amino-1-propanol (PA) under reflux condition. It was thoroughly characterized by FAB-mass, FT-IR, electronic (ligand field), EPR spectroscopic and X-ray crystallographic techniques. The complex crystallizes in the space group C1c1 of the monoclinic system. The unit cell parameters are, a = 17.247(5), b = 20.058(5) Å, c = 15.320(4) Å and β = 109.235(5)°. Extensive H-bonding between the complex anion [Cu(dipic)2]2- and the surrounding cations [PA-H]+ results in a 3D network, supported with additional π-π interactions of the ligand (dipic)2- neighboring units. The SOD mimic activity of the present complex was also examined using NBT assay.

  13. 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.

  14. Pseudomonas aeruginosa phage PaP1 DNA polymerase is an A-family DNA polymerase demonstrating ssDNA and dsDNA 3'-5' exonuclease activity.

    PubMed

    Liu, Binyan; Gu, Shiling; Liang, Nengsong; Xiong, Mei; Xue, Qizhen; Lu, Shuguang; Hu, Fuquan; Zhang, Huidong

    2016-08-01

    Most phages contain DNA polymerases, which are essential for DNA replication and propagation in infected host bacteria. However, our knowledge on phage-encoded DNA polymerases remains limited. This study investigated the function of a novel DNA polymerase of PaP1, which is the lytic phage of Pseudomonas aeruginosa. PaP1 encodes its sole DNA polymerase called Gp90 that was predicted as an A-family DNA polymerase with polymerase and 3'-5' exonuclease activities. The sequence of Gp90 is homologous but not identical to that of other A-family DNA polymerases, such as T7 DNA polymerases (Pol) and DNA Pol I. The purified Gp90 demonstrated a polymerase activity. The processivity of Gp90 in DNA replication and its efficiency in single-dNTP incorporation are similar to those of T7 Pol with processive thioredoxin (T7 Pol/trx). Gp90 can degrade ssDNA and dsDNA in 3'-5' direction at a similar rate, which is considerably lower than that of T7 Pol/trx. The optimized conditions for polymerization were a temperature of 37 °C and a buffer consisting of 40 mM Tris-HCl (pH 8.0), 30 mM MgCl2, and 200 mM NaCl. These studies on DNA polymerase encoded by PaP1 help advance our knowledge on phage-encoded DNA polymerases and elucidate PaP1 propagation in infected P. aeruginosa.

  15. Cat hindlimb motoneurons during locomotion. II. Normal activity patterns.

    PubMed

    Hoffer, J A; Sugano, N; Loeb, G E; Marks, W B; O'Donovan, M J; Pratt, C A

    1987-02-01

    Activity patterns were recorded from 51 motoneurons in the fifth lumbar ventral root of cats walking on a motorized treadmill at a range of speeds between 0.1 and 1.3 m/s. The muscle of destination of recorded motoneurons was identified by spike-triggered averaging of EMG recordings from each of the anterior thigh muscles. Forty-three motoneurons projected to one of the quadriceps (vastus medialis, vastus lateralis, vastus intermedius, or rectus femoris) or sartorius (anterior or medial) muscles of the anterior thigh. Anterior thigh motoneurons always discharged a single burst of action potentials per step cycle, even in multifunctional muscles (e.g., sartorius anterior) that exhibited more than one burst of EMG activity per step cycle. The instantaneous firing rates of most motoneurons were lowest upon recruitment and increased progressively during a burst, as long as the EMG was still increasing. Firing rates peaked midway through each burst and tended to decline toward the end of the burst. The initial, mean, and peak firing rates of single motoneurons typically increased for faster walking speeds. At any given walking speed, early recruited motoneurons typically reached higher firing rates than late recruited motoneurons. In contrast to decerebrated cats, initial doublets at the beginning of bursts were seen only rarely. In the 4/51 motoneurons that showed initial doublets, both the instantaneous frequency of the doublet and the probability of starting a burst with a doublet decreased for faster walking speeds. The modulations in firing rate of every motoneuron were found to be closely correlated to the smoothed electromyogram of its target muscle. For 32 identified motoneurons, the unit's instantaneous frequencygram was scaled linearly by computer to the rectified smoothed EMG recorded from each of the anterior thigh muscles. The covariance between unitary frequencygram and muscle EMG was computed for each muscle. Typically, the EMG profile of the target

  16. Patterns of Physical Activity Outside of School Time among Japanese Junior High School Students

    ERIC Educational Resources Information Center

    He, Li; Ishii, Kaori; Shibata, Ai; Adachi, Minoru; Nonoue, Keiko; Oka, Koichiro

    2013-01-01

    Background: Physical activity is beneficial for adolescent health. The physical activity patterns of Japanese adolescents are relatively unknown. Therefore, this study aimed to describe the current patterns of physical activity and to identify sex and grade differences among them. Methods: The participants comprised 714 Japanese adolescents aged…

  17. Weekday and weekend patterns of physical activity and sedentary time among Liverpool and Madrid youth.

    PubMed

    Ramirez-Rico, Elena; Hilland, Toni A; Foweather, Lawrence; Fernández-Garcia, Emilia; Fairclough, Stuart J

    2014-01-01

    Levels of physical inactivity and sedentary behaviour among English and Spanish youth are high and vary within different regions of each country. Little though is known about these during specific periods of the day. The purpose of this study was to describe physical activity (PA) and sedentary time during segments of the day and week, and compare these critical contexts between youth in the Liverpool and Madrid areas of England and Spain, respectively. PA was objectively assessed in 235 Liverpool- and 241 Madrid youth (aged 10-14 years) who wore accelerometers for seven consecutive days. Minutes of sedentary time, moderate PA, vigorous PA and moderate-to-vigorous physical activity (MVPA) were calculated for weekdays, weekend days, school time, non-school time and after-school. Between-country differences were analysed using analysis of covariance (ANCOVA). Madrid youth spent significantly more time in sedentary activities than their Liverpool counterparts. Madrid youth engaged in more minutes of moderate intensity physical activity (MPA) than Liverpool youth during weekdays, school time and non-school time (P<0.01). Liverpool children recorded more time in vigorous physical activity (VPA) than Madrid peers during week days and weekend days (P<0.01) and during school time and after-school periods (P<0.01). The MVPA was significantly higher among Madrid youth during non-school time (P<0.01). Around 25% of all youth achieved recommended levels of MVPA. Low levels of MVPA and systematic differences in sedentary time, MPA and VPA exist between Liverpool and Madrid youth. Interventions targeted at the least-active children during weekends, after-school and non-school periods within the cultural contexts common to each city are required.

  18. 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…

  19. 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.

  20. The relationship of physical activity (PA) and walking with sarcopenia in Korean males aged 60 years and older using the Fourth Korean National Health and Nutrition Examination Survey (KNHANES IV-2, 3), 2008-2009.

    PubMed

    Kim, Sang-Hwan; Kim, Tae-Ho; Hwang, Hee-Jin

    2013-01-01

    Although a variety of studies have reported the association between age related changes in muscle mass and the functional impairments of the elderly, few have reported on the modifiable lifestyle factors that are related to sarcopenia. Three thousand five hundred ninety-eight men in nationally representative cross-sectional, population-representative sampled survey using data from the KNHANES IV aged 19 years and older who completed a body composition using a dual energy X-ray absorptiometry (DXA) were measured. To determine whether there are any associations between physical activities, nutritional status and sarcopenia were examined in 1156 men among those over 60 years of age. Appendicular skeletal muscle mass (ASM) was calculated as the sum of skeletal muscle in the arms and legs. Sarcopenia was defined as the ASM/Ht(2) of less than two standard deviations (SD) below the sex-specific normal mean for the younger reference group. The prevalence of sarcopenia in Korean men aged 60 years and older was 9.9%. Sarcopenia was negatively associated with the third quartile (OR=0.40, 95% CI=0.20-0.80) and fourth quartile of PA (OR=0.24, 95% CI=0.11-0.52), and negatively associated with the highest quartile of protein intake (OR=0.32, 95% CI=0.14-0.76). In logistic regression models, sarcopenia was negatively associated with walking PA (OR=0.49, 95% CI=0.29-0.83) after an adjustment for age, smoking habits, alcohol drinking, family income, education status and protein intake. Sarcopenia was associated with PA, especially walking PA.

  1. PaR-PaR laboratory automation platform.

    PubMed

    Linshiz, Gregory; Stawski, Nina; Poust, Sean; Bi, Changhao; Keasling, Jay D; Hillson, Nathan J

    2013-05-17

    Labor-intensive multistep biological tasks, such as the construction and cloning of DNA molecules, are prime candidates for laboratory automation. Flexible and biology-friendly operation of robotic equipment is key to its successful integration in biological laboratories, and the efforts required to operate a robot must be much smaller than the alternative manual lab work. To achieve these goals, a simple high-level biology-friendly robot programming language is needed. We have developed and experimentally validated such a language: Programming a Robot (PaR-PaR). The syntax and compiler for the language are based on computer science principles and a deep understanding of biological workflows. PaR-PaR allows researchers to use liquid-handling robots effectively, enabling experiments that would not have been considered previously. After minimal training, a biologist can independently write complicated protocols for a robot within an hour. Adoption of PaR-PaR as a standard cross-platform language would enable hand-written or software-generated robotic protocols to be shared across laboratories.

  2. PaR-PaR Laboratory Automation Platform

    SciTech Connect

    Linshiz, G; Stawski, N; Poust, S; Bi, CH; Keasling, JD; Hilson, NJ

    2013-05-01

    Labor-intensive multistep biological tasks, such as the construction and cloning of DNA molecules, are prime candidates for laboratory automation. Flexible and biology-friendly operation of robotic equipment is key to its successful integration in biological laboratories, and the efforts required to operate a robot must be much smaller than the alternative manual lab work. To achieve these goals, a simple high-level biology-friendly robot programming language is needed. We have developed and experimentally validated such a language: Programming a Robot (PaR-PaR). The syntax and compiler for the language are based on computer science principles and a deep understanding of biological workflows. PaR-PaR allows researchers to use liquid-handling robots effectively, enabling experiments that would not have been considered previously. After minimal training, a biologist can independently write complicated protocols for a robot within an hour. Adoption of PaR-PaR as a standard cross-platform language would enable hand-written or software-generated robotic protocols to be shared across laboratories.

  3. 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.

  4. Nocturnal activity patterns of northern myotis (Myotis septentrionalis) during the maternity season in West Virginia (USA)

    USGS Publications Warehouse

    Johnson, J.B.; Edwards, J.W.; Ford, W.M.

    2011-01-01

    Nocturnal activity patterns of northern myotis (Myotis septentrionalis) at diurnal roost trees remain largely uninvestigated. For example, the influence of reproductive status, weather, and roost tree and surrounding habitat characteristics on timing of emergence, intra-night activity, and entrance at their roost trees is poorly known. We examined nocturnal activity patterns of northern myotis maternity colonies during pregnancy and lactation at diurnal roost trees situated in areas that were and were not subjected to recent prescribed fires at the Fernow Experimental Forest, West Virginia from 2007 to 2009. According to exit counts and acoustic data, northern myotis colony sizes were similar between reproductive periods and roost tree settings. However, intra-night activity patterns differed slightly between reproductive periods and roost trees in burned and non-burned areas. Weather variables poorly explained variation in activity patterns during pregnancy, but precipitation and temperature were negatively associated with activity patterns during lactation. ?? Museum and Institute of Zoology PAS.

  5. Progress toward motor recovery with active neuromuscular stimulation: muscle activation pattern evidence after a stroke.

    PubMed

    Cauraugh, James H; Kim, Sangbum

    2003-03-15

    Chronic cerebrovascular accident individuals with partial paralysis in an upper extremity typically demonstrate difficulty in voluntarily controlling movement initiation. This study investigated patterns of electromyogram (EMG) activation levels while stroke subjects voluntarily initiated their impaired wrist and finger extensor muscles. Twenty subjects were randomly assigned to either a unilateral movement/stimulation group or a bilateral movement/stimulation group. Participants completed 4 days (6 h over 2 weeks) of active neuromuscular stimulation (i.e., 5 s/trial, 90 trials/day, biphasic waveform) on the wrist and finger extensors according to group assignments. The EMG activation levels were analyzed with a three-factor mixed design Motor recovery protocol x Session block x Trial block (2 x 2 x 3) ANOVA with repeated measures on the second and third factors. This robust analysis revealed higher EMG activation levels for the coupled bilateral movement/stimulation group than the unilateral movement/stimulation group. In addition, higher muscle activation levels were found for the second session block as well as trial blocks 2 and 3. Overall, these findings indicated improved motor capabilities of the impaired muscles as evidenced by the higher voluntary EMG activation levels.

  6. Antagonistic Activity and Mode of Action of Phenazine-1-Carboxylic Acid, Produced by Marine Bacterium Pseudomonas aeruginosa PA31x, Against Vibrio anguillarum In vitro and in a Zebrafish In vivo Model.

    PubMed

    Zhang, Linlin; Tian, Xueying; Kuang, Shan; Liu, Ge; Zhang, Chengsheng; Sun, Chaomin

    2017-01-01

    Phenazine and its derivatives are very important secondary metabolites produced from Pseudomonas spp. and have exhibited broad-spectrum antifungal and antibacterial activities. However, till date, there are few reports about marine derived Pseudomonas and its production of phenazine metabolites. In this study, we isolated a marine Pseudomonas aeruginosa strain PA31x which produced natural product inhibiting the growth of Vibrio anguillarum C312, one of the most serious bacterial pathogens in marine aquaculture. Combining high-resolution electro-spray-ionization mass spectroscopy and nuclear magnetic resonance spectroscopy analyses, the functional compound against V. anguillarum was demonstrated to be phenazine-1-carboxylic acid (PCA), an important phenazine derivative. Molecular studies indicated that the production of PCA by P. aeruginosa PA31x was determined by gene clusters phz1 and phz2 in its genome. Electron microscopic results showed that treatment of V. anguillarum with PCA developed complete lysis of bacterial cells with fragmented cytoplasm being released to the surrounding environment. Additional evidence indicated that reactive oxygen species generation preceded PCA-induced microbe and cancer cell death. Notably, treatment with PCA gave highly significant protective activities against the development of V. anguillarum C312 on zebrafish. Additionally, the marine derived PCA was further found to effectively inhibit the growth of agricultural pathogens, Acidovorax citrulli NP1 and Phytophthora nicotianae JM1. Taken together, this study reveals that marine Pseudomonas derived PCA carries antagonistic activities against both aquacultural and agricultural pathogens, which broadens the application fields of PCA.

  7. Antagonistic Activity and Mode of Action of Phenazine-1-Carboxylic Acid, Produced by Marine Bacterium Pseudomonas aeruginosa PA31x, Against Vibrio anguillarum In vitro and in a Zebrafish In vivo Model

    PubMed Central

    Zhang, Linlin; Tian, Xueying; Kuang, Shan; Liu, Ge; Zhang, Chengsheng; Sun, Chaomin

    2017-01-01

    Phenazine and its derivatives are very important secondary metabolites produced from Pseudomonas spp. and have exhibited broad-spectrum antifungal and antibacterial activities. However, till date, there are few reports about marine derived Pseudomonas and its production of phenazine metabolites. In this study, we isolated a marine Pseudomonas aeruginosa strain PA31x which produced natural product inhibiting the growth of Vibrio anguillarum C312, one of the most serious bacterial pathogens in marine aquaculture. Combining high-resolution electro-spray-ionization mass spectroscopy and nuclear magnetic resonance spectroscopy analyses, the functional compound against V. anguillarum was demonstrated to be phenazine-1-carboxylic acid (PCA), an important phenazine derivative. Molecular studies indicated that the production of PCA by P. aeruginosa PA31x was determined by gene clusters phz1 and phz2 in its genome. Electron microscopic results showed that treatment of V. anguillarum with PCA developed complete lysis of bacterial cells with fragmented cytoplasm being released to the surrounding environment. Additional evidence indicated that reactive oxygen species generation preceded PCA-induced microbe and cancer cell death. Notably, treatment with PCA gave highly significant protective activities against the development of V. anguillarum C312 on zebrafish. Additionally, the marine derived PCA was further found to effectively inhibit the growth of agricultural pathogens, Acidovorax citrulli NP1 and Phytophthora nicotianae JM1. Taken together, this study reveals that marine Pseudomonas derived PCA carries antagonistic activities against both aquacultural and agricultural pathogens, which broadens the application fields of PCA. PMID:28289406

  8. 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

  9. Physical Activity and Self-Efficacy in Physical Activity and Healthy Eating in an Urban Elementary Setting

    ERIC Educational Resources Information Center

    Matthews, Tracey D.; O'Neill, Elizabeth; Kostelis, Kimberly T.; Jaffe, Daniel; Vitti, Steven; Quinlan, Melissa; Boland, Michelle

    2015-01-01

    Background: Identifying lifestyle factors such as physical activity (PA) patterns and eating behaviors of children may be beneficial in implementing interventions in urban elementary schools. Purpose: To examine PA levels and self-efficacy (SE) in PA and health eating (HE) of third, fourth, and fifth graders in 3 low economic elementary schools in…

  10. Determination of Total Daily Energy Requirements and Activity Patterns of Service Women

    DTIC Science & Technology

    1997-10-01

    conducted at Fort Bragg/Camp Mckall during a Combat Support Hospital training exercise , during the first year of the grant. Isotope and activity ...water, physical activity patterns energy expenditure, military nutrition, hydration status. 15. NUMBER OF PAGES 15 16. PRICE CODE 17 SECURITY...Devices, Ft. Walton Beach, Fl.) will be employed to assess patterns of rest and activity , total physical activity and to estimate duration and

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

    PubMed

    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

  12. 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

  13. 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.

  14. 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

  15. Diurnal Patterns of Physical Activity in Relation to Activity Induced Energy Expenditure in 52 to 83 Years-Old Adults

    PubMed Central

    Bonomi, Alberto G.; Westerterp, Klaas R.

    2016-01-01

    Background Ageing is associated with a declining physical activity level (PAL) and changes in the diurnal activity pattern. Changes in the activity pattern might help explaining the age-associated reduction of physical activity. Objective The aims were to investigate diurnal activity patterns within groups of older adults classified by PAL, to investigate diurnal activity patterns within age-groups and to investigate the association between the drop in activity and aerobic fitness. Methods Thirty-one healthy subjects aged between 52 and 83y were recruited for the study. Subjects were divided in sedentary (PAL<1.75), moderately active (1.75active (1.90activity patterns were based on activity counts from an accelerometer during wake time and then divided in four quarters of equal time length. Additionally, aerobic fitness was measured as maximal oxygen uptake. Results Subjects had a PAL between 1.43 and 2.34 and an aerobic fitness between 18 and 49 ml/kg/min. Overall, activity patterns showed a peak in the first quarter of wake time (around 10AM) followed by a gradual decline of, on average, 5% per hour. Active subjects reached their peak in the first quarter and remained active until after the third quarter (11% drop each quarter on average). Moderately active and sedentary subjects reached their peak during the second quarter with a decrease during the third quarter (respectively 29% and 17% drop each quarter on average). The drop in physical activity between the first and the second half of the wake time was negatively associated with aerobic fitness (r = -0.39, p<0.05). Conclusion Active older adults maintained a larger amount of body movement for longer during their wake time. Diurnal physical activity declined more in adults ≥66 years old with lower aerobic fitness. PMID:27936145

  16. Patterns of Educational Activities: Discontinuities and Sequences. Report No. 222.

    ERIC Educational Resources Information Center

    Karweit, Nancy

    Using a retrospective life history sample (LHS), the educational activities of white and black men from age 14 to age 30 were determined. A lack of association of family background characteristics with resumption of schooling activities after labor force entry was found for both blacks and whites. Attainment level was related to the likelihood of…

  17. Disease activity patterns over time in patients with SLE: analysis of the Hopkins Lupus Cohort

    PubMed Central

    Györi, Noémi; Giannakou, Ioanna; Chatzidionysiou, Katerina; Magder, Laurence; van Vollenhoven, Ronald F; Petri, Michelle

    2017-01-01

    Objective To describe SLE disease activity patterns in the Hopkins Lupus Cohort. Methods Disease activity was studied in 1886 patients followed-up for 1–28 years. Disease activity patterns were defined using (1) Physician Global Assessment (PGA) and (2) modified SLE Disease Activity Index (M-SLEDAI) as follows: long quiescent (LQ), M-SLEDAI=0/PGA=0 at all visits; relapsing-remitting (RR), periods of activity (M-SLEDAI>0/PGA>0) interspersed with inactivity (M-SLEDAI=0/PGA=0); chronic active (CA), M-SLEDAI>0/PGA>0 at all visits. The pattern of first 3 consecutive follow-up years was determined in 916 patients as: persistent LQ (pLQ), persistent RR (pRR) and persistent CA (pCA), LQ, RR and CA pattern in each of the 3 years, respectively; mixed, at least two different pattern types were identified. Results The RR pattern accounted for the greatest proportion of follow-up time both by M-SLEDAI and PGA, representing 53.8% and 49.9% of total patient-years, respectively. The second most frequent pattern was LQ based on M-SLEDAI (30.7%) and CA based on PGA (40.4%). For the first 3-year intervals, the mixed pattern type was the most common (56.6%). The pRR was the second most frequent (M-SLEDAI 33.3%, PGA 26.5%), while pLQ (M-SLEDAI 6.4%, PGA 0.7%) and pCA were less frequent (M-SLEDAI 3.7%, PGA 16.3%). Conclusions The RR pattern was the most prevalent pattern. LQ was achieved in a subset of patients, using the M-SLEDAI. However, the PGA captured mild activity missed on the M-SLEDAI in these patients. Over a 3-year perspective, less than half of patients maintained their original pattern. PMID:28243457

  18. 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.

  19. 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

  20. Optimization of a mathematical topological pattern for the prediction of antihistaminic activity

    NASA Astrophysics Data System (ADS)

    Duart, M. J.; García-Domenech, R.; Antón-Fos, G. M.; Gálvez, J.

    2001-06-01

    Molecular topology was used to develop a mathematical model capable of classifying compounds according to antihistaminic activity. The equations used for this purpose were derived using multilinear regression and linear discriminant analysis. The topological pattern of activity obtained allows the reliable prediction of antihistaminic activity in drugs frequently used for other therapeutic purposes. Based on the results, the proposed pattern is seemingly only valid for drugs that interact with histamine through competitive inhibition with H1 receptors.

  1. Distributed dynamical computation in neural circuits with propagating coherent activity patterns.

    PubMed

    Gong, Pulin; van Leeuwen, Cees

    2009-12-01

    Activity in neural circuits is spatiotemporally organized. Its spatial organization consists of multiple, localized coherent patterns, or patchy clusters. These patterns propagate across the circuits over time. This type of collective behavior has ubiquitously been observed, both in spontaneous activity and evoked responses; its function, however, has remained unclear. We construct a spatially extended, spiking neural circuit that generates emergent spatiotemporal activity patterns, thereby capturing some of the complexities of the patterns observed empirically. We elucidate what kind of fundamental function these patterns can serve by showing how they process information. As self-sustained objects, localized coherent patterns can signal information by propagating across the neural circuit. Computational operations occur when these emergent patterns interact, or collide with each other. The ongoing behaviors of these patterns naturally embody both distributed, parallel computation and cascaded logical operations. Such distributed computations enable the system to work in an inherently flexible and efficient way. Our work leads us to propose that propagating coherent activity patterns are the underlying primitives with which neural circuits carry out distributed dynamical computation.

  2. Analysis of volcanic activity patterns using MODIS thermal alerts

    NASA Astrophysics Data System (ADS)

    Rothery, Dave A.; Coppola, Diego; Saunders, Charlotte

    2005-07-01

    We investigate eruptive activity by analysis of thermal-alert data from the MODIS (moderate resolution imaging spectrometer) thermal infrared satellite instrument, detected by the MODVOLC (MODIS Volcano alert) algorithm. These data are openly available on the Internet, and easy to use. We show how such data can plug major gaps in the conventional monitoring record of volcanoes in an otherwise generally poorly documented region (Melanesia), including: characterising the mechanism of lava effusion at Pago; demonstrating an earlier-than-realised onset of lava effusion at Lopevi; extending the known period of lava lake activity at Ambrym; and confirming ongoing activity at Bagana, Langila and Tinakula. We also add to the record of activity even at some generally better-monitored volcanoes in Indonesia, but point out that care must be taken to recognise and exclude fires.

  3. Activity Pattern of Urban Adult Students in an Eastern Mediterranean Society.

    PubMed

    Odeh, Issam; Hussein, Tareq

    2016-09-28

    Knowledge of human activity patterns is needed in air pollution exposure and health risk assessment. However, human activity patterns have never been evaluated in the Eastern Mediterranean societies. Therefore, we investigated the activity pattern of 285 subjects (17-63 years) in Amman, Jordan during October to November, 2015. The subjects spent >80% of their time indoors during weekend days and >85% on workdays. They spent ~4.8% and ~5.7% in transportation during weekend days and workdays, respectively. Males had a different activity pattern than females on weekend days, but both genders had similar activity patterns on workdays. On workdays, males spent less time indoors than females. The activity pattern found in this study is a bit different than that for North Americans and Europeans, who spend more time indoors and in transit. The activity pattern found in this study was very different than that observed for Koreans, who spent about 59% and 67% indoors on workdays and weekend, respectively. The main outcomes of this survey can be utilized in human exposure studies. This study and the upcoming future studies have been encouraged and supported by the regional WHO office in Amman.

  4. Holographic optogenetic stimulation of patterned neuronal activity for vision restoration.

    PubMed

    Reutsky-Gefen, Inna; Golan, Lior; Farah, Nairouz; Schejter, Adi; Tsur, Limor; Brosh, Inbar; Shoham, Shy

    2013-01-01

    When natural photoreception is disrupted, as in outer-retinal degenerative diseases, artificial stimulation of surviving nerve cells offers a potential strategy for bypassing compromised neural circuits. Recently, light-sensitive proteins that photosensitize quiescent neurons have generated unprecedented opportunities for optogenetic neuronal control, inspiring early development of optical retinal prostheses. Selectively exciting large neural populations are essential for eliciting meaningful perceptions in the brain. Here we provide the first demonstration of holographic photo-stimulation strategies for bionic vision restoration. In blind retinas, we demonstrate reliable holographically patterned optogenetic stimulation of retinal ganglion cells with millisecond temporal precision and cellular resolution. Holographic excitation strategies could enable flexible control over distributed neuronal circuits, potentially paving the way towards high-acuity vision restoration devices and additional medical and scientific neuro-photonics applications.

  5. 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

  6. Nonuniform spatial patterns of respiratory activity within biofilms during disinfection.

    PubMed Central

    Huang, C T; Yu, F P; McFeters, G A; Stewart, P S

    1995-01-01

    Fluorescent stains in conjunction with cryoembedding and image analysis were applied to demonstrate spatial gradients in respiratory activity within bacterial biofilms during disinfection with monochloramine. Biofilms of Klebsiella pneumoniae and Pseudomonas aeruginosa grown together on stainless steel surfaces in continuous-flow annular reactors were treated with 2 mg of monochloramine per liter (influent concentration) for 2 h. Relatively little biofilm removal occurred as evidenced by total cell direct counts. Plate counts (of both species summed) indicated an average 1.3-log decrease after exposure to 2 mg of monochloramine per liter. The fluorogenic redox indicator 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) and the DNA stain 4',6-diamidino-2-phenylindole (DAPI) were used to differentiate respiring and nonrespiring cells in biofilms. Epifluorescence micrographs of frozen biofilm cross sections clearly revealed gradients of respiratory activity within biofilms in response to monochloramine treatment. These gradients in specific respiratory activity were quantified by calculating the ratio of CTC and DAPI intensities measured by image analysis. Cells near the biofilm-bulk fluid interface lost respiratory activity first. After 2 h of biocide treatment, greater respiratory activity persisted deep in the biofilm than near the biofilm-bulk fluid interface. PMID:7793945

  7. 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.

  8. 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

  9. 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…

  10. Examination of Children's Recess Physical Activity Patterns Using the Activities for Daily Living-Playground Participation (ADL-PP) Instrument

    ERIC Educational Resources Information Center

    Stellino, Megan Babkes; Sinclair, Christina

    2014-01-01

    Thorough assessment of children's physical activity is essential to efficacious interventions to reduce childhood obesity prevalence. The purpose of this study was to examine children's recess physical activity (RPA) patterns of behavior using the Activities of Daily Living-Playground Participation (ADL-PP: Watkinson et al., 2001) instrument.…

  11. Everyday activity patterns and sensory functioning in old age.

    PubMed

    Marsiske, M; Klumb, P; Baltes, M M

    1997-09-01

    In the present study the authors investigated the relationship between visual and auditory acuity and everyday activity functioning. Participants were 516 older adults (70-103 years; equal numbers of men and women) who were members of the age-stratified Berlin Aging Study. Two categories of everyday activity functioning, perceived competence with basic activities of daily living (BaCo; basic competence) and amount of participation in discretionary social and leisure tasks (ExCo; expanded competence), were examined. The results revealed that sensory acuity, particularly vision, was a significant predictor of both BaCo and ExCo (rs ranging from .32 to .47). Indeed, hearing and vision could explain most of the age-related variance in everyday activities. At the same time, in the context of a broader model, evidence for the differential prediction of BaCo and ExCo was found, although there was also evidence for strong general age-related predictive variance that was common to both measures. Discussion focuses on the role of sensory acuity constructs as mediators of age-related variance in psychological and behavioral outcomes and the potential causal implications of this mediation.

  12. Math Activities Using LogoWriter--Patterns and Designs.

    ERIC Educational Resources Information Center

    Flewelling, Gary

    This book is one in a series of teacher resource books developed to: (1) rescue students from the clutches of computers that drill and control; and (2) supply teachers with computer activities compatible with a mathematics program that emphasizes investigation, problem solving, creativity, and hypothesis making and testing. This is not a book…

  13. Activation patterns in forearm muscles during archery shooting.

    PubMed

    Ertan, H; Kentel, B; Tümer, S T; Korkusuz, F

    2003-02-01

    A contraction and relaxation strategy with regard to forearm muscles during the release of the bowstring has often been observed during archery, but has not well been described. The purpose of this study was to analyze this strategy in archers with different levels of expertise; elite, beginner and non-archers. Electromyography (EMG) activity of the M. flexor digitorum superficialis and the M. extensor digitorum were recorded at a sampling frequency of 500 Hz, together with a pulse synchronized with the clicker snap, for twelve shots by each subject. Raw EMG records, 1-s before and after the clicker pulse, were rectified, integrated and normalized. The data was then averaged for successive shots of each subject and later for each group. All subjects including non-archers developed an active contraction of the M. extensor digitorum and a gradual relaxation of the M. flexor digitorum superficialis with the fall of the clicker. In elite archers release started about 100 ms after the fall of the clicker, whereas in beginners and non-archers release started after about 200 and 300 ms, respectively. Non-archers displayed a preparation phase involving extensive extensor activity before the release of the bowstring, which was not observed in elite and beginner archers. In conclusion, archers released the bowstring by active contraction of the forearm extensors, whereas a clear relaxation of the forearm flexors affecting the release movement was not observed.

  14. Fidelity to Theory in PA Intervention Research.

    PubMed

    Keller, Colleen; Fleury, Julie; Sidani, Souraya; Ainsworth, Barbara

    2009-04-01

    Research using theory-based interventions to promote regular physical activity (PA) has increased substantially over the past decade. The purpose of this article is to provide a review and summary of PA intervention research specific to fidelity to intervention theory, providing an overview of the concept of fidelity to intervention theory, defining the evaluative components of fidelity: (a) conceptualization of the problem, (b) operationalization of the theory, (c) specification of mediating processes, and (d) specification of outcome variables. Using journal scans and computerized literature database searches, the authors identified 470 PA activity intervention studies that incorporated a theoretical perspective. A validity framework explicated by was used to summarize intervention research in light of fidelity to intervention theory. In all, 15 intervention studies met the inclusion criteria and were incorporated into the review. Theoretical models for health behavior change, including social cognitive theory (SCT), cognitive behavioral theory (CBT), the transtheoretical model (TTM, the TTM combined with SCT), the reversal theory (theory of psychological reversals), and the disconnected values theory, were used as a basis for intervention design and evaluation.

  15. Diverse patterns of neuroendocrine activity in maltreated children.

    PubMed

    Cicchetti, D; Rogosch, F A

    2001-01-01

    Cortisol regulation was investigated in a sample of school-aged maltreated (n = 175) and demographically comparable low-income nonmaltreated (n = 209) children in the context of a day camp research program. Overall group differences between maltreated and nonmaltreated children were not found for average morning or average afternoon cortisol levels. However, significant variations were found that were based on the subtypes of maltreatment that the children had experienced. Maltreated children who had been both physically and sexually abused (as well as neglected or emotionally maltreated) exhibited substantial elevations in morning cortisol levels; children who had high (>1 SD) cortisol levels in both the morning and afternoon were also overrepresented in the multiple abuse group. Developmental timing of maltreatment did not account for these group differences, whereas the severity of sexual abuse was implicated. In contrast to the multiple abuse group, a subgroup of physically abused children showed evidence of a trend toward lower morning cortisol relative to nonmaltreated children with a significantly smaller decrease in cortisol levels from morning to afternoon. The findings are discussed in terms of the diversity of atypical cortisol regulation patterns that are exhibited among maltreated children.

  16. Seasonal variation of activity patterns in roe deer in a temperate forested area.

    PubMed

    Pagon, Nives; Grignolio, Stefano; Pipia, Anna; Bongi, Paolo; Bertolucci, Cristiano; Apollonio, Marco

    2013-07-01

    We investigated the activity patterns of a European roe deer (Capreolus capreolus) population living in a forested Apennine area in central Italy, in order to shed light on the environmental and biological factors that were expected to account for the observed activity patterns on daily and yearly bases. Daily and seasonal activity patterns of 31 radio-collared roe deer were assessed through sessions of radio tracking for a total period of 18 consecutive months. Roe deer showed bimodal activity patterns throughout the year, with the two highest peaks of activity recorded at dawn and dusk. Activity patterns of males and females differed during the territorial period (from early spring to late summer), whereas they did not during the nonterritorial period. Most likely, behavioral thermoregulation can be held responsible for variation of daily activity patterns in different seasons. In winter, for instance, activity during the dawn period was significantly higher than in other seasons and daylight activity was significantly higher than at night. Nocturnal activity was highest in summer and lowest in winter. During the hunting season, moreover, roe deer showed lower activity levels than during the rest of the year. The prediction that roe deer would show lower activity levels during full moon nights, when the predation risk was assumed to be higher, was not confirmed by our data. Activity rhythms in roe deer were thus subjected to both endogenous and environmental factors, the latter working as exogenous synchronization cues. Accordingly, in changing environmental and ecological conditions, a circadian cycle of activity could be seen as the result of complex interactions among daily behavioral rhythm, digestive physiology, and external modifying factors.

  17. 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

  18. Replicating Physiological Patterns of Activity with Prosthetic Stimulation

    DTIC Science & Technology

    2009-07-01

    that ganglion cells, the output cells of the retina , can be activated directly and exclusively with short duration stimulus pulses[1-4]. However, the...example, the type with the lowest threshold in the human retina is most likely to have the strongest influence on clinical responses. If this is not...oriented to the optic disk side of the retina , but its exact location ranged almost the full 180° within that side). Because the electric field arising

  19. The cortical activation pattern during bilateral arm raising movements

    PubMed Central

    Jang, Sung Ho; Seo, Jung Pyo; Lee, Seung-Hyun; Jin, Sang-Hyun; Yeo, Sang Seok

    2017-01-01

    Bilateral arm raising movements have been used in brain rehabilitation for a long time. However, no study has been reported on the effect of these movements on the cerebral cortex. In this study, using functional near infrared spectroscopy (fNIRS), we attempted to investigate cortical activation generated during bilateral arm raising movements. Ten normal subjects were recruited for this study. fNIRS was performed using an fNIRS system with 49 channels. Bilateral arm raising movements were performed in sitting position at the rate of 0.5 Hz. We measured values of oxyhemoglobin and total hemoglobin in five regions of interest: the primary sensorimotor cortex, premotor cortex, supplementary motor area, prefrontal cortex, and posterior parietal cortex. During performance of bilateral arm raising movements, oxyhemoglobin and total hemoglobin values in the primary sensorimotor cortex, premotor cortex, supplementary motor area, and prefrontal cortex were similar, but higher in these regions than those in the prefrontal cortex. We observed activation of the arm somatotopic areas of the primary sensorimotor cortex and premotor cortex in both hemispheres during bilateral arm raising movements. According to this result, bilateral arm raising movements appeared to induce large-scale neuronal activation and therefore arm raising movements would be good exercise for recovery of brain functions.

  20. Sociocultural patterning of neural activity during self-reflection

    PubMed Central

    Ma, Yina; Bang, Dan; Wang, Chenbo; Allen, Micah; Frith, Chris; Roepstorff, Andreas; Han, Shihui

    2014-01-01

    Western cultures encourage self-construals independent of social contexts, whereas East Asian cultures foster interdependent self-construals that rely on how others perceive the self. How are culturally specific self-construals mediated by the human brain? Using functional magnetic resonance imaging, we monitored neural responses from adults in East Asian (Chinese) and Western (Danish) cultural contexts during judgments of social, mental and physical attributes of themselves and public figures to assess cultural influences on self-referential processing of personal attributes in different dimensions. We found that judgments of self vs a public figure elicited greater activation in the medial prefrontal cortex (mPFC) in Danish than in Chinese participants regardless of attribute dimensions for judgments. However, self-judgments of social attributes induced greater activity in the temporoparietal junction (TPJ) in Chinese than in Danish participants. Moreover, the group difference in TPJ activity was mediated by a measure of a cultural value (i.e. interdependence of self-construal). Our findings suggest that individuals in different sociocultural contexts may learn and/or adopt distinct strategies for self-reflection by changing the weight of the mPFC and TPJ in the social brain network. PMID:22956678

  1. Heart rate and physical activity patterns in persons with profound intellectual and multiple disabilities.

    PubMed

    Waninge, Aly; van der Putten, Annette A J; Stewart, Roy E; Steenbergen, Bert; van Wijck, Ruud; van der Schans, Cees P

    2013-11-01

    Because physical fitness and health are related to physical activity, it is important to gain an insight into the physical activity levels of persons with profound intellectual and multiple disabilities (PIMD). The purpose of this study was to examine heart rate patterns to measure the activity levels of persons with PIMD and to analyze these heart rate patterns according to participant characteristics, observed level of activity, days, and time of day. The heart rate patterns of 24 participants with PIMD were measured continuously using a heart rate monitor for 8 h · d for a period of 6 days. Physical activity levels were measured with questionnaires. Data were analyzed using multilevel analysis. The results indicate that the participants use only 32% of their heart rate reserve over 6 days. The intensity of heart rate reserve ranged from 1 to 62%. On a given day, wide ranges in heart rates between participants and within persons were observed. Between days, only small ranges in the heart rate were found. The participants could be grouped into 4 classes according to their heart rate. In addition, factors such as time of day, physical activity, and age are significantly related to heart rate patterns. In conclusion, this study is an important first step in exploring activity patterns based on heart rate patterns in persons with PIMD. The participants used relatively small fractions of their heart rate reserves. Time of day and age appear to have a considerable influence on heart rate patterns. The observed classes in heart rate patterns suggest that other probably more personal and psychosocial factors have significant influences on heart rate patterns, as well.

  2. 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

  3. Measuring the Actual Levels and Patterns of Physical Activity/Inactivity of Adults with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Finlayson, Janet; Turner, Angela; Granat, Malcolm H.

    2011-01-01

    Background: Lack of regular physical activity is a significant risk to health. The aim of this study was to objectively measure the levels and patterns of activity of adults with intellectual disabilities, to inform the design of studies aimed at increasing activity and health in this population. Materials and Methods: Interviews were conducted…

  4. Airborne antenna pattern calculations

    NASA Technical Reports Server (NTRS)

    Knerr, T. J.; Owens, T. M.; Mielke, R. R.

    1981-01-01

    Calculated principal-and off-principal plane patterns are presented for the following aircraft: de Havilland DHC-7, Rockwell Sabreliner 75A, Piper PA-31T Cheyenne, Lockheed Jet Star II, Piper PA-31-350 Navajo Chieftain, Beechcraft Duke B60, Rockwell Commander 700, Cessna Citation 3, Piper PA-31P Pressurized Navajo, Lear Jet, and Twin Otter DHC-6.

  5. Food Patterns According to Sociodemographics, Physical Activity, Sleeping and Obesity in Portuguese Children

    PubMed Central

    Moreira, Pedro; Santos, Susana; Padrão, Patrícia; Cordeiro, Tânia; Bessa, Mariana; Valente, Hugo; Barros, Renata; Teixeira, Vitor; Mitchell, Vanessa; Lopes, Carla; Moreira, André

    2010-01-01

    Our study aimed to describe the association between food patterns and gender, parental education, physical activity, sleeping and obesity in 1976 children aged 5−10 years old. Dietary intake was measured by a semi quantitative food frequency questionnaire; body mass index was calculated and categorized according to the IOTF classification. Factor analysis and generalized linear models were applied to identify food patterns and their associations. TV viewing and male gender were significant positive predictors for fast-food, sugar sweetened beverages and pastry pattern, while a higher level of maternal education and longer sleeping duration were positively associated with a dietary patterns that included fruit and vegetables. PMID:20617022

  6. The precise temporal pattern of prehearing spontaneous activity is necessary for tonotopic map refinement.

    PubMed

    Clause, Amanda; Kim, Gunsoo; Sonntag, Mandy; Weisz, Catherine J C; Vetter, Douglas E; Rűbsamen, Rudolf; Kandler, Karl

    2014-05-21

    Patterned spontaneous activity is a hallmark of developing sensory systems. In the auditory system, rhythmic bursts of spontaneous activity are generated in cochlear hair cells and propagated along central auditory pathways. The role of these activity patterns in the development of central auditory circuits has remained speculative. Here we demonstrate that blocking efferent cholinergic neurotransmission to developing hair cells in mice that lack the α9 subunit of nicotinic acetylcholine receptors (α9 KO mice) altered the temporal fine structure of spontaneous activity without changing activity levels. KO mice showed a severe impairment in the functional and structural sharpening of an inhibitory tonotopic map, as evidenced by deficits in synaptic strengthening and silencing of connections and an absence in axonal pruning. These results provide evidence that the precise temporal pattern of spontaneous activity before hearing onset is crucial for the establishment of precise tonotopy, the major organizing principle of central auditory pathways.

  7. Technical Insights for Saltstone PA Maintenance

    SciTech Connect

    Flach, G.; Sarkar, S.; Mahadevan, S.; Kosson, D.

    2011-07-20

    compatibility with existing CBP expertise and already-planned activities. Based on these criteria, the five original topics were down-selected to two: external sulfate attack and mechanistic geochemical prediction. For each of the selected topics, the CBP communicated with the PA analysts and subject matter experts at Savannah River to acquire input data specific to the Saltstone facility and related laboratory experiments. Simulations and analyses were performed for both topics using STADIUM (SIMCO 2008), LeachXS/ORCHESTRA (ECN 2007, Meeussen 2003), and other software tools. These supplemental CBP analyses produced valuable technical insights that can be used to strengthen the Saltstone PA using the ongoing PA maintenance process. This report in part summarizes key information gleaned from more comprehensive documents prepared by Sarkar et al. (2010), Samson (2010), and Sarkar (2010).

  8. Alternative Patterning Process for Realization of Large-Area, Full-Color, Active Quantum Dot Display.

    PubMed

    Park, Joon-Suh; Kyhm, Jihoon; Kim, Hong Hee; Jeong, Shinyoung; Kang, JoonHyun; Lee, Song-Ee; Lee, Kyu-Tae; Park, Kisun; Barange, Nilesh; Han, JiYeong; Song, Jin Dong; Choi, Won Kook; Han, Il Ki

    2016-11-09

    Although various colloidal quantum dot (QD) coating and patterning techniques have been developed to meet the demands in optoelectronic applications over the past years, each of the previously demonstrated methods has one or more limitations and trade-offs in forming multicolor, high-resolution, or large-area patterns of QDs. In this study, we present an alternative QD patterning technique using conventional photolithography combined with charge-assisted layer-by-layer (LbL) assembly to solve the trade-offs of the traditional patterning processes. From our demonstrations, we show repeatable QD patterning process that allows multicolor QD patterns in both large-area and microscale. Also, we show that the QD patterns are robust against additional photolithography processes and that the thickness of the QD patterns can be controlled at each position. To validate that this process can be applied to actual device applications as an active material, we have fabricated inverted, differently colored, active QD light-emitting device (QD-LED) on a pixelated substrate, which achieved maximum electroluminescence intensity of 23 770 cd/m(2), and discussed the results. From our findings, we believe that our process provides a solution to achieving both high-resolution and large-scale QD pattern applicable to not only display, but also to practical photonic device research and development.

  9. Fractal patterns of neural activity exist within the suprachiasmatic nucleus and require extrinsic network interactions.

    PubMed

    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.

  10. 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.

  11. Genetic and cytological evidence that heterocyst patterning is regulated by inhibitor gradients that promote activator decay.

    PubMed

    Risser, Douglas D; Callahan, Sean M

    2009-11-24

    The formation of a pattern of differentiated cells from a group of seemingly equivalent, undifferentiated cells is a central paradigm of developmental biology. Several species of filamentous cyanobacteria differentiate nitrogen-fixing heterocysts at regular intervals along unbranched filaments to form a periodic pattern of two distinct cell types. This patterning has been used to exemplify application of the activator-inhibitor model to periodic patterns in biology. The activator-inhibitor model proposes that activators and inhibitors of differentiation diffuse from source cells to form concentration gradients that in turn mediate patterning, but direct visualization of concentration gradients of activators and inhibitors has been difficult. Here we show that the periodic pattern of heterocysts produced by cyanobacteria relies on two inhibitors of heterocyst differentiation, PatS and HetN, in a manner consistent with the predictions of the activator-inhibitor model. Concentration gradients of the activator, HetR, were observed adjacent to heterocysts, the natural source of PatS and HetN, as well as adjacent to vegetative cells that were manipulated to overexpress a gene encoding either of the inhibitors. Gradients of HetR relied on posttranslational decay of HetR. Deletion of both patS and hetN genes prevented the formation of gradients of HetR, and a derivative of the inhibitors was shown to promote decay of HetR in a concentration-dependent manner. Our results provide strong support for application of the activator-inhibitor model to heterocyst patterning and, more generally, the formation of periodic patterns in biological systems.

  12. Anti-listeria activity of poly(lactic acid)/sawdust particle biocomposite film impregnated with pediocin PA-1/AcH and its use in raw sliced pork.

    PubMed

    Woraprayote, Weerapong; Kingcha, Yutthana; Amonphanpokin, Pannawit; Kruenate, Jittiporn; Zendo, Takeshi; Sonomoto, Kenji; Benjakul, Soottawat; Visessanguan, Wonnop

    2013-10-15

    A novel poly(lactic acid) (PLA)/sawdust particle (SP) biocomposite film with anti-listeria activity was developed by incorporation of pediocin PA-1/AcH (Ped) using diffusion coating method. Sawdust particle played an important role in embedding pediocin into the hydrophobic PLA film. The anti-listeria activity of the PLA/SP biocomposite film incorporated with Ped (PLA/SP+Ped) was detected, while no activity against the tested pathogen was observed for the control PLA films (without SP and/or Ped). Dry-heat treatment of film before coating with Ped resulted in the highest Ped adsorption (11.63 ± 3.07 μg protein/cm(2)) and the highest anti-listeria activity. A model study of PLA/SP+Ped as a food-contact antimicrobial packaging on raw sliced pork suggests a potential inhibition of Listeria monocytogenes (99% of total listerial population) on raw sliced pork during the chilled storage. This study supports the feasibility of using PLA/SP+Ped film to reduce the initial load of L. monocytogenes on the surface of raw pork.

  13. 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

  14. Dual function of suppressor of fused in Hh pathway activation and mouse spinal cord patterning.

    PubMed

    Liu, Jinling; Heydeck, Westley; Zeng, Huiqing; Liu, Aimin

    2012-02-15

    The morphogen Sonic hedgehog, one of the Hedgehog (Hh) family of secreted proteins, plays a key role in patterning the mammalian spinal cord along its dorsoventral (D/V) axis through the activation of Glioma-associated oncogene (Gli) family of transcription factors. Suppressor of Fused (Sufu), a Gli-interacting protein, modulates the D/V patterning of the spinal cord by antagonizing Hh signaling. The molecular mechanisms underlying the function of Sufu in Hh pathway activation and spinal cord D/V patterning remain controversial, particularly in light of recent findings that Sufu protects Gli2 and Gli3 proteins from proteasomal degradation. In the current study, we show that Hh pathway activation and dorsal expansion of ventral spinal cord cell types in the absence of Sufu depend on the activator activities of all three Gli family proteins. We also show that Sufu plays a positive role in the maximal activation of Hh signaling that defines the ventral-most cell fate in the mammalian spinal cord, likely through protecting Gli2 and Gli3 proteins from degradation. Finally, by altering the level of Gli3 repressor on a background of reduced Gli activator activities, we reveal an important contribution of Gli3 repressor activity to the Hh pathway activation and the D/V patterning of the spinal cord.

  15. Pleiotropic patterning response to activation of Shh signaling in the limb apical ectodermal ridge.

    PubMed

    Wang, Chi-Kuang Leo; Tsugane, Mizuyo H; Scranton, Victoria; Kosher, Robert A; Pierro, Louis J; Upholt, William B; Dealy, Caroline N

    2011-05-01

    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 apical ectodermal ridge (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 anterior-posterior, proximal-distal, and dorsal-ventral patterning.

  16. 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

  17. 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

  18. Muscle activation patterns when passively stretching spastic lower limb muscles of children with cerebral palsy.

    PubMed

    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 position

  19. 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.

  20. 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…

  1. Elucidating Protactinium Hydrolysis: The Relative Stabilities of PaO2(H2O)(+) and PaO(OH)2(+).

    PubMed

    Dau, Phuong D; Wilson, Richard E; Gibson, John K

    2015-08-03

    It is demonstrated that the gas-phase oxo-exchange of PaO2(+) with water is substantially faster than that of UO2(+), indicating that the Pa-O bonds are more susceptible to activation and formation of the bis-hydroxide intermediate, PaO(OH)2(+). To elucidate the nature of the water adduct of PaO2(+), hydration of PaO2(+) and UO2(+), as well as collision induced dissociation (CID) and ligand-exchange of the water adducts of PaO2(+) and UO2(+), was studied. The results indicate that, in contrast to UO2(H2O)(+), the protactinium oxo bis-hydroxide isomer, PaO(OH)2(+), is produced as a gas-phase species close in energy to the hydrate isomer, PaO2(H2O)(+). CID behavior similar to that of Th(OH)3(+) supports the assignment as PaO(OH)2(+). The gas-phase results are consistent with the spontaneous hydrolysis of PaO2(+) in aqueous solution, this in contrast to later AnO2(+) (An = U, Np, Pu), which forms stable hydrates in both solution and gas phase. In view of the known propensity for Th(IV) to hydrolyze, and previous gas-phase studies of other AnO2(+), it is concluded that the stabilities of oxo-hydroxides relative to oxide hydrates decreases in the order: Th(IV) > Pa(V) > U(V) > Np(V) > Pu(V). This trend suggests increasing covalency and decreasing ionicity of An-O bonds upon proceeding across the actinide series.

  2. The activation patterns of embryonic chick motoneurones projecting to inappropriate muscles.

    PubMed Central

    Landmesser, L T; O'Donovan, M J

    1984-01-01

    Chick lumbosacral motoneurones were caused to innervate foreign muscles by surgically rotating or shifting the limb bud about the anterior-posterior axis in stage 17-18 embryos. The activation pattern of such wrongly projecting motoneurones was assessed at stages 35-38 by recording electromyographic activity from muscles in an isolated spinal cord/hind limb preparation. Muscle activity was classed as flexor- or extensor-like according to the characteristics of the patterned sequence of bursts elicited by a single shock to the thoracic cord. Wrongly projecting motoneurones did not have their activation pattern altered to one appropriate for the muscle innervated; therefore in some cases a particular muscle was activated with a pattern similar to its original one, and in other cases in an opposite manner. Mixed flexor-extensor-like activation of a single muscle was, however, rare. The identity of motoneurones projecting to a muscle was determined by their cord location following retrograde labelling with horseradish peroxidase. This allowed us to conclude that motoneurones could develop their normal pattern of activation even when projecting to foreign muscles. It is concluded that the cord circuits (presumably composed of local interneurones responsible for the activation of motoneurones in the isolated cord preparation are not altered by retrograde influences from the muscle. Wrongly projecting motoneurones, which were maintained throughout the normal cell death period, were activated during spontaneous embryonic movements, and in many cases were found to have a behaviourally inappropriate activation pattern. These observations are discussed in relation to proposed mechanisms by which developmental errors in connectivity are corrected. Images Fig. 1 PMID:6707957

  3. The activation patterns of embryonic chick motoneurones projecting to inappropriate muscles.

    PubMed

    Landmesser, L T; O'Donovan, M J

    1984-02-01

    Chick lumbosacral motoneurones were caused to innervate foreign muscles by surgically rotating or shifting the limb bud about the anterior-posterior axis in stage 17-18 embryos. The activation pattern of such wrongly projecting motoneurones was assessed at stages 35-38 by recording electromyographic activity from muscles in an isolated spinal cord/hind limb preparation. Muscle activity was classed as flexor- or extensor-like according to the characteristics of the patterned sequence of bursts elicited by a single shock to the thoracic cord. Wrongly projecting motoneurones did not have their activation pattern altered to one appropriate for the muscle innervated; therefore in some cases a particular muscle was activated with a pattern similar to its original one, and in other cases in an opposite manner. Mixed flexor-extensor-like activation of a single muscle was, however, rare. The identity of motoneurones projecting to a muscle was determined by their cord location following retrograde labelling with horseradish peroxidase. This allowed us to conclude that motoneurones could develop their normal pattern of activation even when projecting to foreign muscles. It is concluded that the cord circuits (presumably composed of local interneurones responsible for the activation of motoneurones in the isolated cord preparation are not altered by retrograde influences from the muscle. Wrongly projecting motoneurones, which were maintained throughout the normal cell death period, were activated during spontaneous embryonic movements, and in many cases were found to have a behaviourally inappropriate activation pattern. These observations are discussed in relation to proposed mechanisms by which developmental errors in connectivity are corrected.

  4. Oxidation of Gas-Phase Protactinium Ions, Pa+ and Pa2+: Formation and Properties of PaO22+(g), Protactinyl

    SciTech Connect

    Santos, M.; de Matos, A. Pires; Marcalo, J.; Gibson, John K; Haire, Richard {Dick} G; Tyagi, R.; Pitzer, R. M.

    2006-01-01

    Oxidation reactions of bare and ligated, monopositive, and dipositive Pa ions in the gas phase were studied by Fourier transform ion cyclotron resonance mass spectrometry. Seven oxidants were employed, ranging from the thermodynamically robust N{sub 2}O to the relatively weak CH{sub 2}O - all oxidized Pa{sup +} to PaO{sup +} and PaO{sup +} to PaO{sub 2}{sup +}. On the basis of experimental observations, it was established that D[Pa{sup +}-O] and D[OPa{sup +}-O] {ge} 751 kJ mol{sup -1}. Estimates for D[Pa{sup +}-O], D[OPa{sup +}-O], IE[PaO], and IE[PaO{sub 2}] were also obtained. The seven oxidants reacted with Pa{sup 2+} to produce PaO{sup 2+}, indicating that D[Pa{sup 2+}-O] {ge} 751 kJ mol{sup -1}. A particularly notable finding was the oxidation of PaO{sup 2+} by N{sub 2}O to PaO{sub 2}{sup 2+}, a species, which formally comprises Pa(VI). Collision-induced dissociation of PaO{sub 2}{sup 2+} suggested the protactinyl connectivity, {l_brace}O-Pa-O{r_brace}{sup 2+}. The experimentally determined IE[PaO{sub 2}{sup +}] {approx} 16.6 eV is in agreement with self-consistent-field and configuration interaction calculations for PaO{sub 2}{sup +} and PaO{sub 2}{sup 2+}. These calculations provide insights into the electronic structures of these ions and indicate the participation of 5f orbitals in bonding and a partial '6p hole' in the case of protactinyl. It was found that PaO{sub 2}{sup 2+} catalyzes the oxidation of CO by N{sub 2}O - such O atom transport via a dipositive metal oxide ion is distinctive. It was also observed that PaO{sub 2}{sup 2+} is capable of activating H{sub 2} to form the stable PaO{sub 2}H{sup 2+} ion.

  5. 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.

  6. 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.

  7. Acute and chronic psychostimulant treatment modulates the diurnal rhythm activity pattern of WKY female adolescent rats.

    PubMed

    Jones, Cathleen G; Yang, Pamela B; Wilcox, Victor T; Burau, Keith D; Dafny, Nachum

    2014-05-01

    The psychostimulants considered the gold standard in the treatment of attention deficit hyperactivity disorder, one of the most common childhood disorders, are also finding their way into the hands of healthy young adults as brain augmentation to improve cognitive performance. The possible long-term effects of psychostimulant exposure in adolescence are considered controversial, and thus, the objective of this study was to investigate whether the chronic exposure to the psychostimulant amphetamine affects the behavioral diurnal rhythm activity patterns of female adolescent Wistar-Kyoto (WKY) rat. The hypothesis of this study is that change in diurnal rhythm activity pattern is an indicator for the long-term effect of the treatment. Twenty-four rats were divided into two groups, control (N = 12) and experimental (N = 12), and kept in a 12:12-h light/dark cycle in an open-field cage. After 5-7 days of acclimation, 11 days of consecutive non-stop behavioral recordings began. On experimental day 1 (ED1), all groups were given an injection of saline. On ED2 to ED7, the experimental group was injected with 0.6 mg/kg amphetamine followed by 3 days of washout from ED8 to ED10, and amphetamine re-challenge on ED11 similar to ED2. The locomotor movements were counted by the computerized animal activity monitoring system, and the cosinor statistical test analysis was used to fit a 24-h curve of the control recording to the activity pattern after treatment. The horizontal activity, total distance, number of stereotypy, vertical activity, and stereotypical movements were analyzed to find out whether the diurnal rhythm activity patterns were altered. Data obtained using these locomotor indices of diurnal rhythm activity pattern suggest that amphetamine treatment significantly modulates the locomotor diurnal rhythm activity pattern of female WKY adolescent rats.

  8. 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

  9. 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…

  10. 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…

  11. 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…

  12. Cognitive and Metacognitive Activity in Mathematical Problem Solving: Prefrontal and Parietal Patterns

    PubMed Central

    Anderson, John R.; Betts, Shawn; Ferris, Jennifer L.; Fincham, Jon M.

    2010-01-01

    Students were taught an algorithm for solving a new class of mathematical problems. Occasionally in the sequence of problems they encountered exception problems that required that they extend the algorithm. Regular and exception problems were associated with different patterns of brain activation produced. Some regions showed a Cognitive pattern of being active only until the problem was solved and no difference between regular or exception problems. Other regions showed a Metacognitive pattern of greater activity for exception problems and activity that extended into the post-solution period, particularly when an error was made. The Cognitive regions included some of parietal and prefrontal regions associated with the triple-code theory of Dehaene et al (2003) and associated with algebra equation solving in the ACT-R theory (Anderson, 2005). Metacognitive regions included the superior prefrontal gyrus, the angular gyrus of the triple-code theory, and frontopolar regions. PMID:21264650

  13. 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.

  14. 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

  15. Physical Activity Levels in Chinese One-Year-Old Children and Their Parents, an Early STOPP China Study

    PubMed Central

    Hagströmer, Maria; Xiong, Yuelin; Zhang, Lanlan; Zhang, Jianduan; Marcus, Claude

    2016-01-01

    Background Physical activity (PA) is associated with health benefits, already in childhood. However, little is known about actual levels, patterns and gender differences in PA level in very young children. This study examines Chinese one-year-old children and their parents’ PA levels and patterns, and assesses the correlations between children’s PA level and gender, body mass index standard deviation score (BMI SDS), parental BMI and parental PA level. Methods Data from 123 families participating in the Early STOPP China study were used. Families were recruited based on parental BMI and were classified as either high-risk or low-risk of obesity. Parents and children wore an ActiGraph GT3X+ to assess the average PA levels. PA levels and hourly patterns during weekdays and weekends were examined as were correlations with gender, BMI SDS, parental BMI and parental PA levels. Results There were no significant differences in children’s averaged PA between risk groups, genders, or between weekdays and weekends. Children’s peak average activity level was at 7 pm and they were least active at 3 pm (p<0.001). Both mothers and fathers demonstrated a similar PA pattern as their children, although paternal PA level was consistently lower than that of mothers and children. No significant association was found between children’s PA and their gender, BMI SDS, parental BMI or paternal PA levels. Maternal PA was found positively associated with child PA (p<0.05). Conclusion PA in one-year-old Chinese children vary over the day but weekdays and weekends are similar. At this age, children’s PA is not related to gender, BMI SDS, parental BMI or paternal PA. Larger scale studies with more contextual information are needed to improve the understanding of our findings. PMID:27078684

  16. 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

  17. Intra-session repeatability of lower limb muscles activation pattern during pedaling.

    PubMed

    Dorel, Sylvain; Couturier, Antoine; Hug, François

    2008-10-01

    Assessment of intra-session repeatability of muscle activation pattern is of considerable relevance for research settings, especially when used to determine changes over time. However, the repeatability of lower limb muscles activation pattern during pedaling is not fully established. Thus, we tested the intra-session repeatability of the activation pattern of 10 lower limb muscles during a sub-maximal cycling exercise. Eleven triathletes participated to this study. The experimental session consisted in a reference sub-maximal cycling exercise (i.e. 150 W) performed before and after a 53-min simulated training session (mean power output=200+/-12 W). Repeatability of EMG patterns was assessed in terms of muscle activity level (i.e. RMS of the mean pedaling cycle and burst) and muscle activation timing (i.e. onset and offset of the EMG burst) for the 10 following lower limb muscles: gluteus maximus (GMax), semimembranosus (SM), Biceps femoris (BF), vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), gastrocnemius medianus (GM) and lateralis (GL), soleus (SOL) and tibialis anterior (TA). No significant differences concerning the muscle activation level were found between test and retest for all the muscles investigated. Only VM, SOL and TA showed significant differences in muscle activation timing parameters. Whereas ICC and SEM values confirmed this weak repeatability, cross-correlation coefficients suggest a good repeatability of the activation timing parameters for all the studied muscles. Overall, the main finding of this work is the good repeatability of the EMG pattern during pedaling both in term of muscle activity level and muscle activation timing.

  18. Predicting Neural Activity Patterns Associated with Sentences Using a Neurobiologically Motivated Model of Semantic Representation.

    PubMed

    Anderson, Andrew James; Binder, Jeffrey R; Fernandino, Leonardo; Humphries, Colin J; Conant, Lisa L; Aguilar, Mario; Wang, Xixi; Doko, Donias; Raizada, Rajeev D S

    2016-08-12

    We introduce an approach that predicts neural representations of word meanings contained in sentences then superposes these to predict neural representations of new sentences. A neurobiological semantic model based on sensory, motor, social, emotional, and cognitive attributes was used as a foundation to define semantic content. Previous studies have predominantly predicted neural patterns for isolated words, using models that lack neurobiological interpretation. Fourteen participants read 240 sentences describing everyday situations while undergoing fMRI. To connect sentence-level fMRI activation patterns to the word-level semantic model, we devised methods to decompose the fMRI data into individual words. Activation patterns associated with each attribute in the model were then estimated using multiple-regression. This enabled synthesis of activation patterns for trained and new words, which were subsequently averaged to predict new sentences. Region-of-interest analyses revealed that prediction accuracy was highest using voxels in the left temporal and inferior parietal cortex, although a broad range of regions returned statistically significant results, showing that semantic information is widely distributed across the brain. The results show how a neurobiologically motivated semantic model can decompose sentence-level fMRI data into activation features for component words, which can be recombined to predict activation patterns for new sentences.

  19. Quantification of free-living activity patterns using accelerometry in adults with mental illness

    PubMed Central

    Chapman, Justin J.; Roberts, James A.; Nguyen, Vinh T.; Breakspear, Michael

    2017-01-01

    Physical activity is disrupted in many psychiatric disorders. Advances in everyday technologies – such as accelerometers in smart phones – opens exciting possibilities for non-intrusive acquisition of activity data. Successful exploitation of this opportunity requires the validation of analytical methods that can capture the full movement spectrum. The study aim was to demonstrate an analytical approach to characterise accelerometer-derived activity patterns. Here, we use statistical methods to characterize accelerometer-derived activity patterns from a heterogeneous sample of 99 community-based adults with mental illnesses. Diagnoses were screened using the Mini International Neuropsychiatric Interview, and participants wore accelerometers for one week. We studied the relative ability of simple (exponential), complex (heavy-tailed), and composite models to explain patterns of activity and inactivity. Activity during wakefulness was a composite of brief random (exponential) movements and complex (heavy-tailed) processes, whereas movement during sleep lacked the heavy-tailed component. In contrast, inactivity followed a heavy-tailed process, lacking the random component. Activity patterns differed in nature between those with a diagnosis of bipolar disorder and a primary psychotic disorder. These results show the potential of complex models to quantify the rich nature of human movement captured by accelerometry during wake and sleep, and the interaction with diagnosis and health. PMID:28266563

  20. Chromatophore Activity during Natural Pattern Expression by the Squid Sepioteuthis lessoniana: Contributions of Miniature Oscillation

    PubMed Central

    Suzuki, Mamiko; Kimura, Tetsuya; Ogawa, Hiroto; Hotta, Kohji; Oka, Kotaro

    2011-01-01

    Squid can rapidly change the chromatic patterns on their body. The patterns are created by the expansion and retraction of chromatophores. The chromatophore consists of a central pigment-containing cell surrounded by radial muscles that are controlled by motor neurons located in the central nervous system (CNS). In this study we used semi-intact squid (Sepioteuthis lessoniana) displaying centrally controlled natural patterns to analyze spatial and temporal activities of chromatophores located on the dorsal mantle skin. We found that chromatophores oscillated with miniature expansions/retractions at various frequencies, even when the chromatic patterns appear macroscopically stable. The frequencies of this miniature oscillation differed between “feature” and “background” areas of chromatic patterns. Higher frequencies occurred in feature areas, whereas lower frequencies were detected in background areas. We also observed synchronization of the oscillation during chromatic pattern expression. The expansion size of chromatophores oscillating at high frequency correlated with the number of synchronized chromatophores but not the oscillation frequency. Miniature oscillations were not observed in denervated chromatophores. These results suggest that miniature oscillations of chromatophores are driven by motor neuronal activities in the CNS and that frequency and synchrony of this oscillation determine the chromatic pattern and the expansion size, respectively. PMID:21483763

  1. Dietary and physical activity patterns in French children are related to overweight and socioeconomic status.

    PubMed

    Lioret, Sandrine; Touvier, Mathilde; Lafay, Lionel; Volatier, Jean-Luc; Maire, Bernard

    2008-01-01

    Sedentary behavior (SED) has already been identified as a risk factor of childhood overweight (OW) but less is known about the dietary patterns related to adiposity. Our objective was to investigate if lifestyle patterns combining overall diet and physical activity were associated with childhood OW and if they were involved in the reverse association between socioeconomic status (SES) and OW. Dietary intake was assessed using a 7-d food record in 748 French children aged 3-11 y from the 1998-1999 cross-sectional French Enquête Individuelle et Nationale sur les Consommations Alimentaires national food consumption survey. Weight and height, leisure time physical activity, SED (television viewing), and SES were reported by parents or children by answering questionnaires. Scores for lifestyle patterns were assessed with factor analysis and their relationship with OW was explored by logistic regression analysis. Two similar lifestyle patterns were identified in children aged 3-6 y and 7-11 y: "snacking and sedentary" and "varied food and physically active." The snacking and sedentary pattern was positively associated with OW in the youngest children (P-trend = 0.0161) and partly mediated the negative association of SES to OW. The varied food and physically active pattern was inversely correlated with OW in the eldest children only (P-trend = 0.0401). A third pattern called "big eaters at main meals" was derived in children aged 7-11 y and was positively correlated with OW (P-trend = 0.0165). From a public health perspective, the combinations of identifiable dietary and physical activity behaviors may be useful as a basis for recommendations on preventing OW.

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

    PubMed Central

    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

  3. Influence of environmental factors on activity patterns of Incisitermes minor (Isoptera: Kalotermitidae) in naturally infested logs.

    PubMed

    Lewis, Vernard R; Leighton, Shawn; Tabuchi, Robin; Baldwin, James A; Haverty, Michael I

    2013-02-01

    Acoustic emission (AE) activity patterns were measured from seven loquat [Eriobotrya japonica (Thunb.) Lindl.] logs, five containing live western drywood termite [Incisitermes minor (Hagen)] infestations, and two without an active drywood termite infestation. AE activity, as well as temperature, were monitored every 3 min under unrestricted ambient conditions in a small wooden building, under unrestricted ambient conditions but in constant darkness, or in a temperature-controlled cabined under constant darkness. Logs with active drywood termite infestations displayed similar diurnal cycles of AE activity that closely followed temperature with a peak of AE activity late in the afternoon (1700-1800 hours). When light was excluded from the building, a circadian pattern continued and apparently was driven by temperature. When the seven logs were kept at a relatively constant temperature (approximately 23 +/- 0.9 degrees C) and constant darkness, the pattern of activity was closely correlated with temperature, even with minimal changes in temperature. Temperature is the primary driver of activity of these drywood termites, but the effects are different when temperature is increasing or decreasing. At constant temperature, AE activity was highly correlated with the number of termites in the logs. The possible implications of these findings on our understanding of drywood termite biology and how this information may affect inspections and posttreatment evaluations are discussed.

  4. 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

  5. Pattern of trauma determines the threshold for epileptic activity in a model of cortical deafferentation

    PubMed Central

    Volman, Vladislav; Bazhenov, Maxim; Sejnowski, Terrence J.

    2011-01-01

    Epileptic activity often occurs in the cortex after a latent period after head trauma; this delay has been attributed to the destabilizing influence of homeostatic synaptic scaling and changes in intrinsic properties. However, the impact of the spatial organization of cortical trauma on epileptogenesis is poorly understood. We addressed this question by analyzing the dynamics of a large-scale biophysically realistic cortical network model subjected to different patterns of trauma. Our results suggest that the spatial pattern of trauma can greatly affect the propensity for developing posttraumatic epileptic activity. For the same fraction of lesioned neurons, spatially compact trauma resulted in stronger posttraumatic elevation of paroxysmal activity than spatially diffuse trauma. In the case of very severe trauma, diffuse distribution of a small number of surviving intact neurons alleviated posttraumatic epileptogenesis. We suggest that clinical evaluation of the severity of brain trauma should take into account the spatial pattern of the injured cortex. PMID:21896754

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

    PubMed Central

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

    2016-01-01

    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

  7. [Activity patterns and foraging behavior of Apis cerana cerana in the urban gardens in winter].

    PubMed

    Chen, Fa-jun; Yang, Qing-qing; Long, Li; Hu, Hong-mei; Duan, Bin; Chen, Wen-nian

    2016-01-01

    Bees and other pollinating insects are the important parts of biodiversity due to their great role in plant reproduction and crop production. To explore the role of city garden in native bees conservation, activity patterns, visiting behaviors and flowering plants with nectar or pollen were recorded in south Sichuan in winter. The results showed that, worker bees (Apis cerana cerana) were active to collect food out hive under suitable weather conditions, the duration of working was long. Peaks of the number of outgoing, entrance and foragers without pollen appeared at 14:00-15:00, and bimodal patterns were observed. While, peak of bees with pollen appeared at 11:00, and a unimodal pattern was observed. Time significantly affected the activity of workers. The workload of honey bees on nectar and pollen collection were different, just less than twenty percent foragers carrying pollen. Temperature and humidity also affected flights of bees to some degree, and bee activities showed similar patterns on different days. However, the activities had diverse characteristics in some time. Though a less number of plants were in flowering, most of them could be utilized by A. cerana cerana, and colonies could effectively get the food resource by behavior adjustment. In addition, visiting activities of bees on the flowers of main garden plants, such as Camellia japonica, showed obvious rhythm. Increasing the flowering plants with nectar and pollen in winter by scientific management of urban gardens would facilitate the creation of suitable habitats for A. cerana cerana and maintaining the wild population.

  8. Activity Patterns of Free-Ranging Koalas (Phascolarctos cinereus) Revealed by Accelerometry

    PubMed Central

    Ryan, Michelle A.; Whisson, Desley A.; Holland, Greg J.; Arnould, John P. Y.

    2013-01-01

    An understanding of koala activity patterns is important for measuring the behavioral response of this species to environmental change, but to date has been limited by the logistical challenges of traditional field methodologies. We addressed this knowledge gap by using tri-axial accelerometer data loggers attached to VHF radio collars to examine activity patterns of adult male and female koalas in a high-density population at Cape Otway, Victoria, Australia. Data were obtained from 27 adult koalas over two 7-d periods during the breeding season: 12 in the early-breeding season in November 2010, and 15 in the late-breeding season in January 2011. Multiple 15 minute observation blocks on each animal were used for validation of activity patterns determined from the accelerometer data loggers. Accelerometry was effective in distinguishing between inactive (sleeping, resting) and active (grooming, feeding and moving) behaviors. Koalas were more active during the early-breeding season with a higher index of movement (overall dynamic body acceleration [ODBA]) for both males and females. Koalas showed a distinct temporal pattern of behavior, with most activity occurring from mid-afternoon to early morning. Accelerometry has potential for examining fine-scale behavior of a wide range of arboreal and terrestrial species. PMID:24224050

  9. [Typical Patterns of Neuronal Activity in Relay and Nonspecific Thalamic Nuclei in Patients with Spasmodic Torticollis].

    PubMed

    Devetiarov, D A; Semenova, U N; Butiaeva, L I; Sedov, A S

    2015-01-01

    Neuronal activity of 50 neurons in nonspecific (Rt, MD) and relay (Voi, Voa) thalamic nuclei was analyzed. Data were obtained by microelectrode technique during 14 stereotactic operations in patients with spasmodic torticollis. Application of Poincare maps and Gap-statistics allowed to reveal 3 main patterns of neuronal activity: irregular single spikes, low-threshold Ca(2+)-dependent rhythmic (3-5 Hz) bursts and combination of bursts and single spikes. In some cases, grouping (in Voi and Rt nuclei) and long burst (in Voa nucleus) patterns were observed. Grouping pattern consist of low-density groups of spikes with tendency to periodicity in range 1-1.5 Hz. Long burst pattern consist of long dense groups of spikes with random length and invariant interburst intervals. Main numerical estimations of 3 most spread patterns of neuronal activity were obtained by parametric analysis. In results, investigated thalamic nuclei significantly distinguished from each other by characteristics of burst activity but average firing rate of these nuclei hadn't significant differences. These data may be useful for functional identification of thalamic nuclei during stereotactic neurosurgery operation in patients with movement disorders.

  10. [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.

  11. Microfluidic manufacture of rt-PA-loaded echogenic liposomes

    PubMed Central

    Kandadai, Madhuvanthi A.; Mukherjee, Prithviraj; Shekhar, Himanshu; Shaw, George J.; Papautsky, Ian; Holland, Christy K.

    2016-01-01

    Echogenic liposomes (ELIP), loaded with recombinant tissue-type plasminogen activator (rt-PA) and microbubbles that act as cavitation nuclei, are under development for ultrasound-mediated thrombolysis. Conventional manufacturing techniques produce a polydisperse rt-PA-loaded ELIP population with only a small percentage of particles containing microbubbles. Further, a polydisperse population of rt-PA-loaded ELIP has a broadband frequency response with complex bubble dynamics when exposed to pulsed ultrasound. In this work, a microfluidic flow-focusing device was used to generate monodisperse rt-PA-loaded ELIP (µtELIP) loaded with a perfluorocarbon gas. The rt-PA associated with the µtELIP was encapsulated within the lipid shell as well as intercalated within the lipid shell. The µtELIP had a mean diameter of 5 µm, a resonance frequency of 2.2 MHz, and were found to be stable for at least 30 min in 0.5%bovine serum albumin. Additionally, 35 % of µtELIP particles were estimated to contain microbubbles, an order of magnitude higher than that reported previously for batch-produced rt-PA-loaded ELIP. These findings emphasize the advantages offered by microfluidic techniques for improving the encapsulation efficiency of both rt-PA and perflurocarbon microbubbles within echogenic liposomes. PMID:27206512

  12. Physical Education and General Health Courses and Minority Community College Student Risk Levels for Poor Health and Leisure-Time Exercise Patterns

    ERIC Educational Resources Information Center

    Sullivan, Sally L.; Keating, Xiaofen Deng; Chen, Li; Guan, Jianmin; Delzeit-McIntyre, Linda; Bridges, Dwan

    2008-01-01

    College education is the last opportunity to educate a large segment of young adults to be physically active and develop a healthy lifestyle. This study examined minority community college student risks for cardiovascular disease, physical activity (PA) patterns, and effects of physical education and general health courses on promoting PA.…

  13. 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.

  14. Contrasting activity patterns of two related octopus species, Octopus macropus and Octopus vulgaris.

    PubMed

    Meisel, Daniela V; Byrne, Ruth A; Kuba, Michael; Mather, Jennifer; Ploberger, Werner; Reschenhofer, Erhard

    2006-08-01

    Octopus macropus and Octopus vulgaris have overlapping habitats and are exposed to similar temporal changes. Whereas the former species is described as nocturnal in the field, there are conflicting reports about the activity time of the latter one. To compare activity patterns, the authors tested both species in the laboratory. Octopuses were exposed to a light-dark cycle and held under constant dim light for 7 days each. O. macropus showed nocturnal and light-cued activity. According to casual observations, O. vulgaris started out nocturnal but had switched to mostly diurnal when the experiment began. Individual variation of its activity was found. The different activity patterns of O. macropus and O. vulgaris might reflect their lifestyles, the latter species being more generalist.

  15. The surface geometry of inherited joint and fracture trace patterns resulting from active and passive deformation

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.; Gold, D. P.

    1974-01-01

    Hypothetical models are considered for detecting subsurface structure from the fracture or joint pattern, which may be influenced by the structure and propagated to the surface. Various patterns of an initially orthogonal fracture grid are modeled according to active and passive deformation mechanisms. In the active periclinal structure with a vertical axis, fracture frequency increased both over the dome and basin, and remained constant with decreasing depth to the structure. For passive periclinal features such as a reef or sand body, fracture frequency is determined by the arc of curvature and showed a reduction over the reefmound and increased over the basin.

  16. Differences in activity profile of bacterial cultures studied by dynamic speckle patterns

    NASA Astrophysics Data System (ADS)

    Ramírez-Miquet, E. E.; Otero, I.; Rodríguez, D.; Darias, J. G.; Combarro, A. M.; Contreras, O. R.

    2013-02-01

    We outline the main differences in the activity profile of bacterial cultures studied by dynamic laser speckle (or biospeckle) patterns. The activity is detected in two sorts of culture mediums. The optical setup and the experimental procedure are presented. The experimentally obtained images are processed by the temporal difference method and a qualitative assessment is made with the time history of speckle patterns of the sample. The main differences are studied after changing the culture medium composition. We conclude that the EC medium is suitable to detect the E. coli bacterial presence in early hours and that Mueller Hinton agar delays some additional hours to make possible the assessment of bacteria in time.

  17. 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

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

    PubMed

    Bourobou, Serge Thomas Mickala; Yoo, Younghwan

    2015-05-21

    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.

  19. SPM95 sensitivity to size, intensity and asymmetry of brain activation/deactivation patterns

    SciTech Connect

    Levy, A.V.; Volkow, N.D.; Alexoff, D.

    1996-05-01

    Statistical Parametric Mapping (Friston, SPM95), is used widely to ascertain the statistical significance between different brain patterns induced by functional activation, drug, effects or mental illness. Our purpose is to understand the limitations of applying the SPM95 methodology. We used a group of 8 FDG PET (CTI 931) studies from normal resting human subjects and via software we activated or deactivated the same specific pixel patterns (ROIs), across the group and observed if SPM95 performed correctly. A set of 6 experiments was designed with varying ROI intensities, (from +/-2% to +/-100% of original ROI value), varying ROI sizes, (from 76 to 656 mm{sup 2}) and different locations in the brain, (cortical and/or subcortical). In experiments where the selected activation pattern was spatially symmetric SPM95 identified correctly areas of activation for cortical ROIs as small as 76 mm{sup 2} having as low as a 10% activation with p<0.01; larger areas, 656 mm{sup 2} can be correctly identified even down to only 2%. In activation experiments with left/right cortical or anterior/posterior cortical asymmetry, SPM95 reported Type II errors for levels larger than +/-20% activation/deactivation. In experiments with left/right striatum asymmetry larger than +/-20% SPM95 reported Type I Errors. In experiments where the level of asymmetry was changes while keeping one ROI as a control at the same level of activation, SPM95 erroneously reported different p values for its statistical significance. One of the typical Type I Errors is shown in the figure as an ROI along the brain`s edge; this type of error has been previously observed to be caused by residual spatial registration errors that induce false activation signals. We conclude that while the statistical part of SPM95 performs correctly, the spatial registration method used in SPM95 has residual registration errors sensitive to the type of activation pattern.

  20. Cardiovascular activity in blood-injection-injury phobia during exposure: evidence for diphasic response patterns?

    PubMed

    Ritz, Thomas; Meuret, Alicia E; Simon, Erica

    2013-08-01

    Exposure to feared stimuli in blood-injection-injury (BII)-phobia is thought to elicit a diphasic response pattern, with an initial fight-flight-like cardiovascular activation followed by a marked deactivation and possible fainting (vasovagal syncope). However, studies have remained equivocal on the importance of such patterns. We therefore sought to determine the prevalence and clinical relevance of diphasic responses using criteria that require a true diphasic response to exceed cardiovascular activation of an emotional episode of a negative valence and to exceed deactivation of an emotionally neutral episode. Sixty BII-phobia participants and 20 healthy controls were exposed to surgery, anger and neutral films while measuring heart rate, blood pressure, respiratory pattern, and end-tidal partial pressure of carbon dioxide (as indicator of hyperventilation). Diphasic response patterns were observed in up to 20% of BII-phobia participants and 26.6% of healthy controls for individual cardiovascular parameters. BII-phobia participants with diphasic patterns across multiple parameters showed more fear of injections and blood draws, reported the strongest physical symptoms during the surgery film, and showed the strongest tendency to hyperventilate. Thus, although only a minority of individuals with BII phobia shows diphasic responses, their occurrence indicates significant distress. Respiratory training may add to the treatment of BII phobia patients that show diphasic response patterns.

  1. The variability of co-activation pattern of antagonist muscles in human infant crawling.

    PubMed

    Xiong, Qi L; Wu, Xiao Y; Nong Xiao; Zeng, Si Y; Zheng, Xiao L; Di Wu; Hou, Wen S

    2016-08-01

    Infant crawling is part of normal human gross motor development, and a 4-beat gait that involves rhythmical flexion and extension of limbs and the underlying muscle co-activation of antagonist muscle around the joint. However, detection the co-activation pattern of antagonist muscle are sparse due to the general difficulty of measuring locomotion in human infants. In this paper, sEMG of antagonist muscles and the corresponding kinematics data of limbs were collected when infants were crawling on hands and knees at their self-selected speed. The infant's gross motor developmental status was assessed by the global Gross Motor Function Measure Scale (GMFM-88) as well. The method based on EMG-EMG plots was used to quantify the variability of co-activation pattern of antagonist muscle. After that, we observed that antagonist muscles of upper limb (triceps brachii and biceps brachii) showed less variability of co-activation pattern of muscles than lower limb(quadriceps femoris and hamstrings) during crawling, and this variability was also varied in different crawling phases (stance and swing). Furthermore, we found some varied behaviors in the co-activation patterns of antagonist muscles when gross motor developmental level increased. The preliminary work suggests that such adaptive changes may be related to the adjustment of neuromuscular in the early stage of gross motor development.

  2. a Three-Step Spatial-Temporal Clustering Method for Human Activity Pattern Analysis

    NASA Astrophysics Data System (ADS)

    Huang, W.; Li, S.; Xu, S.

    2016-06-01

    How people move in cities and what they do in various locations at different times form human activity patterns. Human activity pattern plays a key role in in urban planning, traffic forecasting, public health and safety, emergency response, friend recommendation, and so on. Therefore, scholars from different fields, such as social science, geography, transportation, physics and computer science, have made great efforts in modelling and analysing human activity patterns or human mobility patterns. One of the essential tasks in such studies is to find the locations or places where individuals stay to perform some kind of activities before further activity pattern analysis. In the era of Big Data, the emerging of social media along with wearable devices enables human activity data to be collected more easily and efficiently. Furthermore, the dimension of the accessible human activity data has been extended from two to three (space or space-time) to four dimensions (space, time and semantics). More specifically, not only a location and time that people stay and spend are collected, but also what people "say" for in a location at a time can be obtained. The characteristics of these datasets shed new light on the analysis of human mobility, where some of new methodologies should be accordingly developed to handle them. Traditional methods such as neural networks, statistics and clustering have been applied to study human activity patterns using geosocial media data. Among them, clustering methods have been widely used to analyse spatiotemporal patterns. However, to our best knowledge, few of clustering algorithms are specifically developed for handling the datasets that contain spatial, temporal and semantic aspects all together. In this work, we propose a three-step human activity clustering method based on space, time and semantics to fill this gap. One-year Twitter data, posted in Toronto, Canada, is used to test the clustering-based method. The results show that the

  3. Sedentary and Physical Activity Habits of Obese Adolescents

    ERIC Educational Resources Information Center

    Starkoff, Brooke E.; Petosa, Rick L.; Balk, Elizabeth K.; Eneli, Ihuoma U.; Bonny, Andrea E.; Hoffman, Robert P.; Devor, Steven T.

    2014-01-01

    Background: The independent association between sedentary behavior (SB) and physical activity (PA) is such that, regardless of accumulated PA, high amounts of SB are detrimental to health, even in adolescents. Purpose: Our aim was to profile activity patterns in free-living environments and to measure levels of SB and light (LT) and moderate (MOD)…

  4. Crystal Structures of An F420-Dependent Glucose-6-Phosphate Dehydrogenase Fgd1 Involved in the Activation of the Anti-Tb Drug Candidate Pa-824 Reveal the Basis of Coenzyme And Substrate Binding

    SciTech Connect

    Bashiri, G.; Squire, C.J.; Moreland, N.J.; Baker, E.N.

    2009-05-11

    The modified flavin coenzyme F{sub 420} is found in a restricted number of microorganisms. It is widely distributed in mycobacteria, however, where it is important in energy metabolism, and in Mycobacterium tuberculosis (Mtb) is implicated in redox processes related to non-replicating persistence. In Mtb, the F{sub 420}-dependent glucose-6-phosphate dehydrogenase FGD1 provides reduced F{sub 420} for the in vivo activation of the nitroimidazopyran prodrug PA-824, currently being developed for anti-tuberculosis therapy against both replicating and persistent bacteria. The structure of M. tuberculosis FGD1 has been determined by x-ray crystallography both in its apo state and in complex with F{sub 420} and citrate at resolutions of 1.90 and 1.95{angstrom}, respectively. The structure reveals a highly specific F{sub 420} binding mode, which is shared with several other F{sub 420}-dependent enzymes. Citrate occupies the substrate binding pocket adjacent to F{sub 420} and is shown to be a competitive inhibitor (IC{sub 50} 43 {micro}m). Modeling of the binding of the glucose 6-phosphate (G6P) substrate identifies a positively charged phosphate binding pocket and shows that G6P, like citrate, packs against the isoalloxazine moiety of F{sub 420} and helps promote a butterfly bend conformation that facilitates F{sub 420} reduction and catalysis.

  5. Association of After-School Physical Activity Levels and Organized Physical Activity Participation in Hong Kong Children

    ERIC Educational Resources Information Center

    Cheung, Peggy PY

    2012-01-01

    The aims of this study were to 1) describe the children's physical activity (PA) patterns during the after-school period and 2) to compare the type and intensity of activity during the after-school period of children with or without participation in organized PA programmes. The participants were 456 children from four primary schools in Hong Kong.…

  6. Neurotensin Changes Propulsive Activity into a Segmental Motor Pattern in the Rat Colon

    PubMed Central

    Li, Hongfei; Chen, Ji-Hong; Yang, Zixian; Huang, Min; Yu, Yuanjie; Tan, Shiyun; Luo, Hesheng; Huizinga, Jan D

    2016-01-01

    Background/Aims Neurotensin is a gut-brain peptide with both inhibitory and excitatory actions on the colonic musculature; our objective was to understand the implications of this for motor patterns occurring in the intact colon of the rat. Methods The effects of neurotensin with concentrations ranging from 0.1–100 nM were studied in the intact rat colon in vitro, by investigating spatio-temporal maps created from video recordings of colonic motility before and after neurotensin. Results Low concentration of neurotensin (0.1–1 nM) inhibited propagating long distance contractions and rhythmic propagating motor complexes; in its place a slow propagating rhythmic segmental motor pattern developed. The neurotensin receptor 1 antagonist SR-48692 prevented the development of the segmental motor pattern. Higher concentrations of neurotensin (10 nM and 100 nM) were capable of restoring long distance contraction activity and inhibiting the segmental activity. The slow propagating segmental contraction showed a rhythmic contraction—relaxation cycle at the slow wave frequency originating from the interstitial cells of Cajal associated with the myenteric plexus pacemaker. High concentrations given without prior additions of low concentrations did not evoke the segmental motor pattern. These actions occurred when neurotensin was given in the bath solution or intraluminally. The segmental motor pattern evoked by neurotensin was inhibited by the neural conduction blocker lidocaine. Conclusions Neurotensin (0.1–1 nM) inhibits the dominant propulsive motor patterns of the colon and a distinct motor pattern of rhythmic slow propagating segmental contractions develops. This motor pattern has the hallmarks of haustral boundary contractions. PMID:26882114

  7. Isolating weather effects from seasonal activity patterns of a temperate North American Colubrid.

    PubMed

    George, Andrew D; Thompson, Frank R; Faaborg, John

    2015-08-01

    Forecasting the effects of climate change on threatened ecosystems and species will require an understanding of how weather influences processes that drive population dynamics. We have evaluated weather effects on activity patterns of western ratsnakes, a widespread predator of birds and small mammals in eastern North America. From 2010-2013 we radio-tracked 53 ratsnakes in the fragmented region of central Missouri. We relocated each snake 4× per week and used movement frequency as an index of activity. We used generalized linear mixed models within an information-theoretic approach to evaluate temporal and weather variables as potential predictors of snake activity. While snakes were generally sedentary, activity showed a linear response to relative humidity and a quadratic response to air temperature, peaking near 30 °C. Seasonal activity patterns differed between sexes and among years, but snakes were generally least active in mid-summer, regardless of weather. Our findings provide strong evidence that air temperature and relative humidity differentially affect activity patterns of an important predator and are the mechanism explaining increased nest predation rates with warmer temperatures.

  8. Truncated seasonal activity patterns of the western blacklegged tick (Ixodes pacificus) in central and southern California.

    PubMed

    MacDonald, Andrew J; Briggs, Cheryl J

    2016-02-01

    Patterns of seasonal activity and density of host-seeking western blacklegged ticks, Ixodes pacificus, were investigated in central and southern California. Weekly to monthly drag sampling was undertaken at two sites in Santa Barbara County and one site in Los Angeles County over multiple years. Adult I. pacificus became active in the winter (late November) and were rare or absent by late April to early May. Nymphal ticks became active in early to late February, were absent by early May to early June, and were rarely encountered using the drag method throughout their period of peak seasonal activity. Larval ticks became active earlier in the season, or at the same time as nymphs (early to late February) and were absent by early May. These results suggest a highly truncated period of I. pacificus seasonal questing activity, particularly apparent in the juvenile tick stages, in central and southern California relative to observed patterns in Lyme-endemic northwestern California. Notably, the highly truncated period of questing activity of the juvenile stages has important implications for pathogen transmission dynamics in that there exists only a brief window for horizontally transmitted pathogens to be acquired by one tick cohort and subsequently transmitted, through hosts, to the next tick cohort in this system. The broader patterns observed also suggest low human risk of tick-borne disease in central and southern California, and have implications for reduced tick-borne disease risk in the western US more generally under projected climate change.

  9. Nonlinear analysis of human physical activity patterns in health and disease

    NASA Astrophysics Data System (ADS)

    Paraschiv-Ionescu, A.; Buchser, E.; Rutschmann, B.; Aminian, K.

    2008-02-01

    The reliable and objective assessment of chronic disease state has been and still is a very significant challenge in clinical medicine. An essential feature of human behavior related to the health status, the functional capacity, and the quality of life is the physical activity during daily life. A common way to assess physical activity is to measure the quantity of body movement. Since human activity is controlled by various factors both extrinsic and intrinsic to the body, quantitative parameters only provide a partial assessment and do not allow for a clear distinction between normal and abnormal activity. In this paper, we propose a methodology for the analysis of human activity pattern based on the definition of different physical activity time series with the appropriate analysis methods. The temporal pattern of postures, movements, and transitions between postures was quantified using fractal analysis and symbolic dynamics statistics. The derived nonlinear metrics were able to discriminate patterns of daily activity generated from healthy and chronic pain states.

  10. Western lowland gorillas (Gorilla gorilla gorilla) change their activity patterns in response to frugivory.

    PubMed

    Masi, Shelly; Cipolletta, Chloé; Robbins, Martha M

    2009-02-01

    The most important environmental factor explaining interspecies variation in ecology and sociality of the great apes is likely to be variation in resource availability. Relatively little is known about the activity patterns of western lowland gorillas (Gorilla gorilla gorilla), which inhabit a dramatically different environment from the well-studied mountain gorillas (G. beringei beringei). This study aims to provide a detailed quantification of western lowland gorillas' activity budgets using direct observations on one habituated group in Bai Hokou, Central African Republic. We examined how activity patterns of both sexes are shaped by seasonal frugivory. Activity was recorded with 5-min instantaneous sampling between December 2004 and December 2005. During the high-frugivory period the gorillas spent less time feeding and more time traveling than during the low-frugivory period. The silverback spent less time feeding but more time resting than both females and immatures, which likely results from a combination of social and physiological factors. When compared with mountain gorillas, western lowland gorillas spend more time feeding (67 vs. 55%) and traveling (12 vs. 6.5%), but less time resting (21 vs. 34%) and engaging in social/other activities (0.5 vs. 3.6%). This disparity in activity budgets of western lowland gorillas and mountain gorillas may be explained by the more frugivorous diet and the greater dispersion of food resources experienced by western lowland gorillas. Like other apes, western lowland gorillas change their activity patterns in response to changes in the diet.

  11. Adult Female Rats Altered Diurnal Locomotor Activity Pattern Following Chronic Methylphenidate Treatment

    PubMed Central

    Trinh, T.; Kohllepin, S; Yang, P.B.; Burau, K.D.; Dafny, N.

    2014-01-01

    Methylphenidate (MPD) is one of the most prescribed pharmacological agents and also used as cognitive enhancement and for recreational purposes. The objective of this study was to investigate the repetitive dose-response effects of MPD on rhythm locomotor activity pattern of female WKY rats and compare to prior study done on male. The hypothesis is that change in the circadian activity pattern indicates a long-lasting effect of the drug. Four animal groups (saline control, 0.6, 2.5, and 10.0 mg/kg MPD dose groups) were housed in a sound-controlled room at 12:12 light/dark cycle. All received saline injections on experimental day 1 (ED 1). On EDs 2-7, the control group received saline injection; the other groups received 0.6, 2.5, or 10.0 mg/kg MPD, respectively. On ED 8-10, injections were withheld. On ED 11, each group received the same dose as EDs 2-7. Hourly histograms and cosine statistical analyses calculating the acrophase (ϕ), amplitude (A), and MESOR (M) were applied to assess the 24-hour circadian activity pattern. The 0.6 and 2.5 mg/kg MPD groups exhibited significant (p<0.05) change in their circadian activity pattern on ED 11. The 10.0 mg/kg MPD group exhibited tolerance on ED 11 and also a significant change in activity pattern on ED 8 compared to ED 1, consistent with withdrawal behavior (p<0.007). In conclusion, chronic MPD administration alters circadian locomotor activity of adult female WKY rats and confirms that chronic MPD use elicits long lasting effects PMID:23893293

  12. Soil Landscape Pattern Changes in Response to Rural Anthropogenic Activity across Tiaoxi Watershed, China

    PubMed Central

    Xiao, Rui; Jiang, Diwei; Christakos, George; Fei, Xufeng; Wu, Jiaping

    2016-01-01

    Soil sealing (loss of soil resources due to extensive land covering for the purpose of house building, road construction etc.) and subsequent soil landscape pattern changes constitute typical environmental problems in many places worldwide. Previous studies concentrated on soil sealing in urbanized regions, whereas rural areas have not been given sufficient attention. Accordingly, this paper studies soil landscape pattern dynamics (i.e., landscape pattern changes in response to rural anthropogenic activities) in the Tiaoxi watershed (Zhejiang province, eastern China), in which surface sealing is by far the predominant component of human forcing with respect to environmental change. A novel approach of quantifying the impacts of rural anthropogenic activities on soil resources is presented. Specifically, quantitative relationships were derived between five soil landscape pattern metrics (patch density, edge density, shape index, Shannon’s diversity index and aggregation index) and three rural anthropogenic activity indicators (anthropogenic activity intensity, distance to towns, and distance to roads) at two landscape block scales (3 and 5 km) between 1985 and 2010. The results showed that the Tiaoxi watershed experienced extensive rural settlement expansion and high rates of soil sealing. Soil landscapes became more fragmented, more irregular, more isolated, and less diverse. Relationships between soil landscape pattern changes and rural anthropogenic activities differed with the scale (spatial and temporal) and variable considered. In particular, the anthropogenic activity intensity was found to be the most important indicator explaining social development intensity, whereas the other two proximity indicators had a significant impact at certain temporal interval. In combination with scale effects, spatial dependency (correlation) was shown to play a key role that should be carefully taken into consideration in any relevant environmental study. Overall, the

  13. Evolution of activity patterns and chromatic vision in primates: morphometrics, genetics and cladistics.

    PubMed

    Heesy, C P; Ross, C F

    2001-02-01

    Hypotheses for the adaptive origin of primates have reconstructed nocturnality as the primitive activity pattern for the entire order based on functional/adaptive interpretations of the relative size and orientation of the orbits, body size and dietary reconstruction. Based on comparative data from extant taxa this reconstruction implies that basal primates were also solitary, faunivorous, and arboreal. Recently, primates have been hypothesized to be primitively diurnal, based in part on the distribution of color-sensitive photoreceptor opsin genes and active trichromatic color vision in several extant strepsirrhines, as well as anthropoid primates (Tan & Li, 1999 Nature402, 36; Li, 2000 Am. J. phys. Anthrop. Supple.30, 318). If diurnality is primitive for all primates then the functional and adaptive significance of aspects of strepsirrhine retinal morphology and other adaptations of the primate visual system such as high acuity stereopsis, have been misinterpreted for decades. This hypothesis also implies that nocturnality evolved numerous times in primates. However, the hypothesis that primates are primitively diurnal has not been analyzed in a phylogenetic context, nor have the activity patterns of several fossil primates been considered. This study investigated the evolution of activity patterns and trichromacy in primates using a new method for reconstructing activity patterns in fragmentary fossils and by reconstructing visual system character evolution at key ancestral nodes of primate higher taxa. Results support previous studies that reconstruct omomyiform primates as nocturnal. The larger body sizes of adapiform primates confound inferences regarding activity pattern evolution in this group. The hypothesis of diurnality and trichromacy as primitive for primates is not supported by the phylogenetic data. On the contrary, nocturnality and dichromatic vision are not only primitive for all primates, but also for extant strepsirrhines. Diurnality, and

  14. Motives for using Facebook, patterns of Facebook activities, and late adolescents' social adjustment to college.

    PubMed

    Yang, Chia-chen; Brown, B Bradford

    2013-03-01

    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 late adolescents' social adjustment to the college environment. Anonymous self-report survey data from 193 mostly European American students (M age = 20.32; 54 % female) attending a major Midwestern university indicated that motives and activity patterns were associated directly with social adjustment, but the association between one activity, status updating, and social adjustment also was moderated by the motive of relationship maintenance. Findings provide a more comprehensive portrait of how Facebook use may foster or inhibit social adjustment in college.

  15. 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.

  16. Dopamine regulates distinctively the activity patterns of striatal output neurons in advanced parkinsonian primates

    PubMed Central

    Singh, Arun; Liang, Li; Kaneoke, Yoshiki; Cao, Xuebing

    2014-01-01

    Nigrostriatal dopamine denervation plays a major role in basal ganglia circuitry disarray and motor abnormalities of Parkinson's disease (PD). Studies in rodent and primate models have revealed that striatal projection neurons, namely, medium spiny neurons (MSNs), increase the firing frequency. However, their activity pattern changes and the effects of dopaminergic stimulation in such conditions are unknown. Using single-cell recordings in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated primates with advanced parkinsonism, we studied MSN activity patterns in the transition to different motor states following levodopa administration. In the “off” state (baseline parkinsonian disability), a burst-firing pattern accompanied by prolonged silences (pauses) was found in 34% of MSNs, and 80% of these exhibited a levodopa response compatible with dopamine D1 receptor activation (direct pathway MSNs). This pattern was highly responsive to levodopa given that bursting/pausing almost disappeared in the “on” state (reversal of parkinsonism after levodopa injection), although this led to higher firing rates. Nonbursty MSNs fired irregularly with marked pausing that increased in the on state in the MSN subset with a levodopa response compatible with dopamine D2 receptor activation (indirect pathway MSNs), although the pause increase was not sustained in some units during the appearance of dyskinesias. Data indicate that the MSN firing pattern in the advanced parkinsonian monkey is altered by bursting and pausing changes and that dopamine differentially and inefficiently regulates these behaviorally correlated patterns in MSN subpopulations. These findings may contribute to understand the impact of striatal dysfunction in the basal ganglia network and its role in motor symptoms of PD. PMID:25505120

  17. 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

  18. Effects of Cooperative Group Work Activities on Pre-School Children's Pattern Recognition Skills

    ERIC Educational Resources Information Center

    Tarim, Kamuran

    2015-01-01

    The aim of this research is twofold; to investigate the effects of cooperative group-based work activities on children's pattern recognition skills in pre-school and to examine the teachers' opinions about the implementation process. In line with this objective, for the study, 57 children (25 girls and 32 boys) were chosen from two private schools…

  19. The Relationship between Class Size and Online Activity Patterns in Asynchronous Computer Conferencing Environments

    ERIC Educational Resources Information Center

    Hewitt, Jim; Brett, Clare

    2007-01-01

    This study analyzes the relationship between class size and student online activity patterns in a series of 28 graduate level computer conferencing courses. Quantitative analyses of note production, average note size, note opening and note reading percentages found a significant positive correlation between class size and mean number of notes…

  20. A Study of Verbal Behavior Patterns in Primary Grade Classrooms During Science Activities.

    ERIC Educational Resources Information Center

    Moon, Thomas C.

    This paper reports a study of selected examples of verbal behavior patterns in primary grade classrooms during science activities. The subjects were 32 elementary teachers within five mid-Michigan public school districts. A control group of 16 teachers taught science in the conventional manner. The experimental group received an in-depth study of…

  1. Abnormal fMRI Activation Pattern during Story Listening in Individuals with Down Syndrome

    ERIC Educational Resources Information Center

    Reynolds Losin, Elizabeth A.; Rivera, Susan M.; O'Hare, Elizabeth D.; Sowell, Elizabeth R.; Pinter, Joseph D.

    2009-01-01

    Down syndrome is characterized by disproportionately severe impairments of speech and language, yet little is known about the neural underpinnings of these deficits. We compared fMRI activation patterns during passive story listening in 9 young adults with Down syndrome and 9 approximately age-matched, typically developing controls. The typically…

  2. Sex Differences in Mental Rotation and Cortical Activation Patterns: Can Training Change Them?

    ERIC Educational Resources Information Center

    Jausovec, Norbert; Jausovec, Ksenija

    2012-01-01

    In two experiments the neuronal mechanisms of sex differences in mental rotation were investigated. In Experiment 1 cortical activation was studied in women and men with similar levels of mental rotation ability (high, and average to low), who were equalized with respect to general intelligence. Sex difference in neuroelectric patterns of brain…

  3. An Ecological Momentary Assessment of the Physical Activity and Sedentary Behaviour Patterns of University Students

    ERIC Educational Resources Information Center

    Rouse, Peter C.; Biddle, Stuart J. H.

    2010-01-01

    Objective: We used ecological momentary assessment to understand the physical activity and sedentary behaviour patterns of university students. Study design: Cross sectional, opportunistic sample from a university in the English midlands. Methods: Ecological momentary assessment diaries were completed every 15 minutes across two days. The sample…

  4. Physical Activity Patterns in University Students: Do They Follow the Public Health Guidelines?

    PubMed Central

    Clemente, Filipe Manuel; Nikolaidis, Pantelis Theodoros; Martins, Fernando Manuel Lourenço; Mendes, Rui Sousa

    2016-01-01

    Physical activity is associated with health. The aim of this study was (a) to access if Portuguese university students meet the public health recommendations for physical activity and (b) the effect of gender and day of the week on daily PA levels of university students. This observational cross-sectional study involved 126 (73 women) healthy Portuguese university students aged 18–23 years old. Participants wore the ActiGraph wGT3X-BT accelerometer for seven consecutive days. Number of steps, time spent sedentary and in light, moderate and vigorous physical activity were recorded. The two-way MANOVA revealed that gender (p-value = 0.001; η2 = 0.038; minimum effect) and day of the week (p-value = 0.001; η2 = 0.174; minimum effect) had significant main effects on the physical activity variables. It was shown that during weekdays, male students walked more steps (65.14%), spent less time sedentary (6.77%) and in light activities (3.11%) and spent more time in moderate (136.67%) and vigorous activity (171.29%) in comparison with weekend days (p < 0.05). The descriptive analysis revealed that female students walked more steps (51.18%) and spent more time in moderate (125.70%) and vigorous (124.16%) activities during weekdays than in weekend days (p < 0.05). Women students did not achieve the recommended 10,000 steps/day on average during weekdays and weekend days. Only male students achieved this recommendation during weekdays. In summary, this study showed a high incidence of sedentary time in university students, mainly on weekend days. New strategies must be adopted to promote physical activity in this population, focusing on the change of sedentary behaviour. PMID:27022993

  5. The influence of family and culture on physical activity among female adolescents from the Indian diaspora.

    PubMed

    Ramanathan, Subha; Crocker, Peter R E

    2009-04-01

    In this study we explored the role of personal, familial, and cultural attitudes and social norms for physical activity (PA) on actual PA behavior among female adolescents of the Indian diaspora. Six girls, 15 to 19 years of age, from a spiritual center participated in interviews and a focus group. Data were analyzed using content analysis. Participants were high in familism, and felt that PA was important for physical and mental health, and to strengthen relationships with family. Fathers and brothers were considered most influential on PA patterns. Differentiated gender roles in PA emerged: boys were deemed more aggressive and competitive, and girls were perceived to promote fun-based learning environments. The importance of religion and spirituality as influences on PA emerged among participants with strong affinities for Indian cultures. Results show that cultural heritage impacts PA norms, attitudes, and patterns, and must be considered when evaluating adolescent PA participation in multicultural societies.

  6. Complementary Role of Frontoparietal Activity and Cortical Pattern Similarity in Successful Episodic Memory Encoding

    PubMed Central

    Xue, Gui; Dong, Qi; Chen, Chuansheng; Lu, Zhong-Lin; Mumford, Jeanette A.; Poldrack, Russell A.

    2013-01-01

    One central goal in cognitive neuroscience of learning and memory is to characterize the neural processes that lead to long-lasting episodic memory. In addition to the stronger frontoparietal activity, greater category- or item-specific cortical representation during encoding, as measured by pattern similarity (PS), is also associated with better subsequent episodic memory. Nevertheless, it is unknown whether frontoparietal activity and cortical PS reflect distinct mechanisms. To address this issue, we reanalyzed previous data (Xue G, Dong Q, Chen C, Lu ZL, Mumford JA, Poldrack RA. 2010. Greater neural pattern similarity across repetitions is associated with better memory. Science. 330:97, Experiment 3) using a novel approach based on combined activation-based and information-based analyses. The results showed that across items, stronger frontoparietal activity was associated with greater PS in distributed brain regions, including those where the PS was predictive of better subsequent memory. Nevertheless, the item-specific PS was still associated with later episodic memory after controlling the effect of frontoparietal activity. Our results suggest that one possible mechanism of frontoparietal activity on episodic memory encoding is via enhancing PS, resulting in more unique and consistent input to the medial temporal lobe. In addition, they suggest that PS might index additional processes, such as pattern reinstatement as a result of study-phase retrieval, that contribute to episodic memory encoding. PMID:22645250

  7. Effect of Frustration on Brain Activation Pattern in Subjects with Different Temperament

    PubMed Central

    Bierzynska, Maria; Bielecki, Maksymilian; Marchewka, Artur; Debowska, Weronika; Duszyk, Anna; Zajkowski, Wojciech; Falkiewicz, Marcel; Nowicka, Anna; Strelau, Jan; Kossut, Malgorzata

    2016-01-01

    In spite of the prevalence of frustration in everyday life, very few neuroimaging studies were focused on this emotional state. In the current study we aimed to examine effects of frustration on brain activity while performing a well-learned task in participants with low and high tolerance for arousal. Prior to the functional magnetic resonance imaging session, the subjects underwent 2 weeks of Braille reading training. Frustration induction was obtained by using a novel highly difficult tactile task based on discrimination of Braille-like raised dots patterns and negative feedback. Effectiveness of this procedure has been confirmed in a pilot study using galvanic skin response and questionnaires. Brain activation pattern during tactile discrimination task before and after frustration were compared directly. Results revealed changes in brain activity in structures mostly reported in acute stress studies: striatum, cingulate cortex, insula, middle frontal gyrus and precuneus and in structures engaged in tactile Braille discrimination: SI and SII. Temperament type affected activation pattern. Subjects with low tolerance for arousal showed higher activation in the posterior cingulate gyrus, precuneus, and inferior parietal lobule than high reactivity group. Even though performance in the discrimination trials following frustration was unaltered, we observed increased activity of primary and secondary somatosensory cortex processing the tactile information. We interpret this effect as an indicator of additional involvement required to counteract the effects of frustration. PMID:26793136

  8. Dusk to dawn activity patterns of anopheline mosquitoes in West Timor and Java, Indonesia.

    PubMed

    Ndoen, Ermi; Wild, Clyde; Dale, Pat; Sipe, Neil; Dale, Mike

    2011-05-01

    Malaria is a serious health issue in Indonesia. We investigated the dusk to dawn anopheline mosquito activity patterns, host-seeking and resting locations in coastal plain, hilly and highland areas in West Timor and Java. Adult mosquitoes were captured landing on humans or resting in houses or animal barns. Data analyzed were: mosquito night-time activities; period of peak activity; night-time activity in specific periods of time and for mosquito resting locations. Eleven species were recorded; data were sparse for some species therefore detailed analyses were performed for four species only. In Java Anopheles vagus was common, with a bimodal pattern of high activity. In West Timor, its activity peaked around midnight. Other species with peak activity around the middle of the night were An. barbirostris and An. subpictus. Most species showed no biting and resting preference for indoors or outdoors, although An. barbirostris preferred indoors in West Timor, but outdoors in Java. An. aconitus and An. annularis preferred resting in human dwellings; An. subpictus and An. vagus preferred resting in animal barns. An. barbirostris preferred resting in human dwellings in West Timor and in animal barns in Java. The information is useful for planning the mosquito control aspect of malaria management. For example, where mosquito species have peak activity at night indoors, bednets and indoor residual spraying should reduce malaria risk, but where mosquitoes are most active outdoors, other options may be more effective.

  9. The impact of human activity patterns on asymptomatic infectious processes in complex networks

    NASA Astrophysics Data System (ADS)

    Li, Mingjie; Orgun, Mehmet A.; Xiao, Jinghua; Zhong, Weicai; Xue, Liyin

    2012-07-01

    The study of the impact of human activity patterns on network dynamics has attracted a lot of attention in recent years. However, individuals' knowledge of their own physical states has rarely been incorporated into modeling processes. In real life, for certain infectious processes, infected agents may not have any visible or physical signs and symptoms; therefore, they may believe that they are uninfected even when they have been infected asymptomatically. This infection awareness factor is covered neither in the classical epidemic models such as SIS nor in network propagation studies. In this article, we propose a novel infectious process model that differentiates between the infection awareness states and the physical states of individuals and extend the SIS model to deal with both asymptomatic infection characteristics and human activity patterns. With regards to the latter, we focus particularly on individuals' testing action, which is to determine whether an individual is infected by an epidemic. The simulation results show that less effort is required in controlling the disease when the transmission probability is either very small or large enough and that Poisson activity patterns are more effective than heavy-tailed patterns in controlling and eliminating asymptomatic infectious diseases due to the long-tail characteristic.

  10. Time budget and activity patterns of oncilla cats (Leopardus tigrinus) in captivity.

    PubMed

    Resende, Letícia de Souza; Neto, Glauce Lima e; Carvalho, Patrícia Gonçalves Duarte; Landau-Remy, Gabriella; Ramos-Júnior, Valdir de Almeida; Andriolo, Artur; Genaro, Gelson

    2014-01-01

    Researchers have reported on the diet of Leopardus tigrinus and ecological aspects, but studies of behavior are scarce. The aims of this study were to describe the time budget and activity patterns of 10 captive Leopardus tigrinus individuals. The group had an activity budget of 66% resting, 20.66% moving, 6.08% vigilant, 3.12% feeding, and 4.14% other activities during 720 hr of observations. The activity budgets of the males and females did not differ significantly; however, males ate more than did females. The nonhuman animals spent more time resting during the day than during the night. Moving, socializing, maintenance, and vigilance showed statistically higher mean values at night. Group analysis of the temporal pattern of behavior showed bimodal peaks. Activity levels were high from 5 a.m. to 6 a.m. and decreased through the day only to peak again at 7 p.m. Stereotypic pacing peaked at dawn and at dusk. Patterns of vigilance, feeding, and maintenance were also determined for the group during a 24-hr period. These results may be useful for the development of management plans and effective conservation strategies for captive cats.

  11. Daily Activity and Nest Occupation Patterns of Fox Squirrels (Sciurus niger) throughout the Year

    PubMed Central

    Wassmer, Thomas; Refinetti, Roberto

    2016-01-01

    The authors investigated the general activity and nest occupation patterns of fox squirrels in a natural setting using temperature-sensitive data loggers that measure activity as changes in the microenvironment of the animal. Data were obtained from 25 distinct preparations, upon 14 unique squirrels, totaling 1385 recording days. The animals were clearly diurnal, with a predominantly unimodal activity pattern, although individual squirrels occasionally exhibited bimodal patterns, particularly in the spring and summer. Even during the short days of winter (9 hours of light), the squirrels typically left the nest after dawn and returned before dusk, spending only about 7 hours out of the nest each day. Although the duration of the daily active phase did not change with the seasons, the squirrels exited the nest earlier in the day when the days became longer in the summer and exited the nest later in the day when the days became shorter in the winter, thus tracking dawn along the seasons. During the few hours spent outside the nest each day, fox squirrels seemed to spend most of the time sitting or lying. These findings suggest that fox squirrels may have adopted a slow life history strategy that involves long periods of rest on trees and short periods of ground activity each day. PMID:26963918

  12. Holographic fiber bundle system for patterned optogenetic activation of large-scale neuronal networks

    PubMed Central

    Farah, Nairouz; Levinsky, Alexandra; Brosh, Inbar; Kahn, Itamar; Shoham, Shy

    2015-01-01

    Abstract. Optogenetic perturbation has become a fundamental tool in controlling activity in neurons. Used to control activity in cell cultures, slice preparations, anesthetized and awake behaving animals, optical control of cell-type specific activity enables the interrogation of complex systems. A remaining challenge in developing optical control tools is the ability to produce defined light patterns such that power-efficient, precise control of neuronal populations is obtained. Here, we describe a system for patterned stimulation that enables the generation of structured activity in neurons by transmitting optical patterns from computer-generated holograms through an optical fiber bundle. The system couples the optical system to versatile fiber bundle configurations, including coherent or incoherent bundles composed of hundreds of up to several meters long fibers. We describe the components of the system, a method for calibration, and a detailed power efficiency and spatial specificity quantification. Next, we use the system to precisely control single-cell activity as measured by extracellular electrophysiological recordings in ChR2-expressing cortical cell cultures. The described system complements recent descriptions of optical control systems, presenting a system suitable for high-resolution spatiotemporal optical control of wide-area neural networks in vitro and in vivo, yielding a tool for precise neural system interrogation. PMID:26793741

  13. Composite catalyst surfaces: Effect of inert and active heterogeneities on pattern formation

    SciTech Connect

    Baer, M.; Bangia, A.K.; Kevrekidis, I.G.; Haas, G.; Rotermund, H.H.; Ertl, G.

    1996-12-05

    Spatiotemporal dynamics in reaction-diffusion systems can be altered through the properties (reactivity, diffusivity) of the medium in which they occur. We construct active heterogeneous media (composite catalytic surfaces with inert as well as active illusions) using microelectronics fabrication techniques and study the spatiotemporal dynamics of heterogeneous catalytic reactions on these catalysts. In parallel, we perform simulations as well as numerical stability and bifurcation analysis of these patterns using mechanistic models. At the limit of large heterogeneity `grain size` (compared to the wavelength of spontaneously arising structures) the interaction patterns with inert or active boundaries dominates (e.g., pinning, transmission, and boundary breakup of spirals, interaction of pulses with corners, `pacemaker` effects). At the opposite limit of very small or very finely distributed heterogeneity, effective behavior is observed (slight modulation of pulses, nearly uniform oscillations, effective spirals). Some representative studies of transitions between the two limits are presented. 48 refs., 11 figs.

  14. Crystal structure of the flavoenzyme PA4991 from Pseudomonas aeruginosa

    SciTech Connect

    Jacewicz, Agata; Schnell, Robert; Lindqvist, Ylva; Schneider, Gunter

    2016-01-22

    PA4991 is a FAD-dependent oxidoreductase from the pathogen P. aeruginosa that is essential for virulence and survival in the infected host. The structure of this enzyme, determined to 2.4 Å resolution, reveals that PA4991 belongs to the GR{sub 2} family of flavoenzymes. The locus PA4991 in Pseudomonas aeruginosa encodes an open reading frame that has been identified as essential for the virulence and/or survival of this pathogenic organism in the infected host. Here, it is shown that this gene encodes a monomeric FAD-binding protein of molecular mass 42.2 kDa. The structure of PA4991 was determined by a combination of molecular replacement using a search model generated with Rosetta and phase improvement by a low-occupancy heavy-metal derivative. PA4991 belongs to the GR{sub 2} family of FAD-dependent oxidoreductases, comprising an FAD-binding domain typical of the glutathione reductase family and a second domain dominated by an eight-stranded mixed β-sheet. Most of the protein–FAD interactions are via the FAD-binding domain, but the isoalloxazine ring is located at the domain interface and interacts with residues from both domains. A comparison with the structurally related glycine oxidase and glycerol-3-phosphate dehydrogenase shows that in spite of very low amino-acid sequence identity (<18%) several active-site residues involved in substrate binding in these enzymes are conserved in PA4991. However, enzymatic assays show that PA4991 does not display amino-acid oxidase or glycerol-3-phosphate dehydrogenase activities, suggesting that it requires different substrates for activity.

  15. [Co-integration of BLG-LAtPA and WAP improved the expression of LAtPA in transgenic mouse milk].

    PubMed

    Zhou, J; Deng, J X; Cheng, X; Lu, Y F; Yang, X; Huang, P T

    2001-01-01

    In order to improve the expression of longer acting tissue plasminogen activator in the mammary epithelium of transgenic mice, the fragment of BLG-LAtPA hydrid gene was microinjected into mouse embryos with mice whey acid protein gene. Three mouse were tested as being Co-integration of BLG-LAtPA and WAP transgene by PCR and Southern blot. Milk obtained from lactating females contains biologically active tPA, and the concentration of tPA was calculated to be about 10 micrograms/mL.

  16. The Pediocin PA-1 Accessory Protein Ensures Correct Disulfide Bond Formation in the Antimicrobial Peptide Pediocin PA-1.

    PubMed

    Oppegård, Camilla; Fimland, Gunnar; Anonsen, Jan Haug; Nissen-Meyer, Jon

    2015-05-19

    Peptides, in contrast to proteins, are generally not large enough to form stable and well-defined three-dimensional structures. However, peptides are still able to form correct disulfide bonds. Using pediocin-like bacteriocins, we have examined how this may be achieved. Some pediocin-like bacteriocins, such as pediocin PA-1 and sakacin P[N24C+44C], have four cysteines. There are three possible ways by which the four cysteines may combine to form two disulfide bonds, and the three variants are expected to be produced in approximately equal amounts if their formation is random. Pediocin PA-1 and sakacin P[N24C+44C] with correct disulfide bonds were the main products when they were secreted by the pediocin PA-1 ABC transporter and accessory protein, but when they were secreted by the corresponding secretion machinery for sakacin A, a pediocin-like bacteriocin with one disulfide bond (two cysteines), peptides with all three possible disulfide bonds were produced in approximately equal amounts. All five cysteines in the pediocin PA-1 ABC transporter and the two cysteines (that form a CxxC motif) in the accessory protein were individually replaced with serines to examine their involvement in disulfide bond formation in pediocin PA-1. The Cys86Ser mutation in the accessory protein caused a 2-fold decrease in the amount of pediocin PA-1 with correct disulfide bonds, while the Cys83Ser mutation nearly abolished the production of pediocin PA-1 and resulted in the production of all three disufide bond variants in equal amounts. The Cys19Ser mutation in the ABC transporter completely abolished secretion of pediocin PA-1, suggesting that Cys19 is in the proteolytic active site and involved in cleaving the prebacteriocin. Replacing the other four cysteines in the ABC transporter with serines caused a slight reduction in the overall amount of secreted pediocin PA-1, but the relative amount with the correct disulfide bonds remained large. These results indicate that the pediocin

  17. Daily and seasonal activity patterns of free range South-American rattlesnake (Crotalus durissus).

    PubMed

    Tozetti, Alexandro M; Martins, Marcio

    2013-09-01

    This study aimed at describing daily and seasonal variation in the activity of a population of South-American rattlesnakes (Crotalus durissus) in a savanna like habitat (Cerrado) in Southeastern Brazil. Seasonal and daily activities of snakes were evaluated by the number of captures of snakes during road surveys, accidental encounters, and relocations by radio-tracking. Our results show that climatic variables such as air temperature and rainfall have little influence on the activity pattern of rattlesnakes. Our findings indicate that rattlesnakes spend most of the day resting and most of the night in ambush posture. The South-American rattlesnake is active throughout the year with a discrete peak in activity of males during the matting season. The possibility of maintaining activity levels even during the coldest and driest season can facilitate the colonization of several habitats in South America. This possibility currently facilitates the colonization of deforested areas by rattlesnakes.

  18. Crystal structure of the flavoenzyme PA4991 from Pseudomonas aeruginosa

    PubMed Central

    Jacewicz, Agata; Schnell, Robert; Lindqvist, Ylva; Schneider, Gunter

    2016-01-01

    The locus PA4991 in Pseudomonas aeruginosa encodes an open reading frame that has been identified as essential for the virulence and/or survival of this pathogenic organism in the infected host. Here, it is shown that this gene encodes a monomeric FAD-binding protein of molecular mass 42.2 kDa. The structure of PA4991 was determined by a combination of molecular replacement using a search model generated with Rosetta and phase improvement by a low-occupancy heavy-metal derivative. PA4991 belongs to the GR2 family of FAD-dependent oxidoreductases, comprising an FAD-binding domain typical of the glutathione reductase family and a second domain dominated by an eight-stranded mixed β-sheet. Most of the protein–FAD interactions are via the FAD-binding domain, but the isoalloxazine ring is located at the domain interface and interacts with residues from both domains. A comparison with the structurally related glycine oxidase and glycerol-3-phosphate dehydrogenase shows that in spite of very low amino-acid sequence identity (<18%) several active-site residues involved in substrate binding in these enzymes are conserved in PA4991. However, enzymatic assays show that PA4991 does not display amino-acid oxidase or glycerol-3-phosphate dehydrogenase activities, suggesting that it requires different substrates for activity. PMID:26841760

  19. Enabling active and healthy ageing decision support systems with the smart collection of TV usage patterns.

    PubMed

    Billis, Antonis S; Batziakas, Asterios; Bratsas, Charalampos; Tsatali, Marianna S; Karagianni, Maria; Bamidis, Panagiotis D

    2016-03-01

    Smart monitoring of seniors behavioural patterns and more specifically activities of daily living have attracted immense research interest in recent years. Development of smart decision support systems to support the promotion of health smart homes has also emerged taking advantage of the plethora of smart, inexpensive and unobtrusive monitoring sensors, devices and software tools. To this end, a smart monitoring system has been used in order to extract meaningful information about television (TV) usage patterns and subsequently associate them with clinical findings of experts. The smart TV operating state remote monitoring system was installed in four elderly women homes and gathered data for more than 11 months. Results suggest that TV daily usage (time the TV is turned on) can predict mental health change. Conclusively, the authors suggest that collection of smart device usage patterns could strengthen the inference capabilities of existing health DSSs applied in uncontrolled settings such as real senior homes.

  20. Enabling active and healthy ageing decision support systems with the smart collection of TV usage patterns

    PubMed Central

    Billis, Antonis S.; Batziakas, Asterios; Bratsas, Charalampos; Tsatali, Marianna S.; Karagianni, Maria

    2016-01-01

    Smart monitoring of seniors behavioural patterns and more specifically activities of daily living have attracted immense research interest in recent years. Development of smart decision support systems to support the promotion of health smart homes has also emerged taking advantage of the plethora of smart, inexpensive and unobtrusive monitoring sensors, devices and software tools. To this end, a smart monitoring system has been used in order to extract meaningful information about television (TV) usage patterns and subsequently associate them with clinical findings of experts. The smart TV operating state remote monitoring system was installed in four elderly women homes and gathered data for more than 11 months. Results suggest that TV daily usage (time the TV is turned on) can predict mental health change. Conclusively, the authors suggest that collection of smart device usage patterns could strengthen the inference capabilities of existing health DSSs applied in uncontrolled settings such as real senior homes. PMID:27284457

  1. The Implications of Null Patterns and Output Unit Activation Functions on Simulation Studies of Learning: A Case Study of Patterning

    ERIC Educational Resources Information Center

    Yaremchuk, V.; Willson, L.R.; Spetch, M.L.; Dawson, M.R.W.

    2005-01-01

    Animal learning researchers have argued that one example of a linearly nonseparable problem is negative patterning, and therefore they have used more complicated multilayer networks to study this kind of discriminant learning. However, it is shown in this paper that previous attempts to define negative patterning problems to artificial neural…

  2. Pattern formation for active particles on optically created ordered and disordered substrates (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Reichhardt, Charles M.; Ray, Dipanjan; Reichhardt, Cynthia J.

    2015-08-01

    There has been tremendous growth in the field of active matter, where the individual particles that comprise the system are self-driven. Examples of this class of system include biological systems such as swimming bacteria and crawling cells. More recently, non-biological swimmers have been created using colloidal Janus particles that undergo chemical reactions on one side to produce self-propulsion. These active matter systems exhibit a wide variety of behaviors that are absent in systems undergoing purely thermal fluctuations, such as transitions from uniform liquids to clusters or living crystals, pushing objects around, ratchet effects, and phase separation in mixtures of active and passive particles. Here we examine the collective effects of active matter disks in the presence of static or dynamic substrates. For colloids, such substrates could be created optically in the form of periodic, random, or quasiperiodic patterns. For thermal particles, increasing the temperature generally increases the diffusion or mobility of the particles when they move over a random or periodic substrates. We find that when the particles are active, increasing the activity can increase the mobility for smaller run lengths but decrease the mobility at large run lengths. Additionally we find that at large run lengths on a structured substrate, a variety of novel active crystalline states can form such as stripes, squares and triangular patterns.

  3. Diel Patterns of Activity for Insect Pollinators of Two Oil Palm Species (Arecales : Arecaceae).

    PubMed

    Auffray, Thomas; Frérot, Brigitte; Poveda, Roberto; Louise, Claude; Beaudoin-Ollivier, Laurence

    2017-01-01

    The pollination of two oil palm species, Elaeis guineensis Jacquin and Elaeis oleifera Cortés (Arecales: Arecaceae), depends on a mutualistic relation with insects, which use male inflorescences as a brood site, and visits female inflorescences lured by the emitted odor, which is similar to that of males. Although the activity of visiting the inflorescences by these insects is critical for the adequate natural pollination of the host plant, their activity is poorly documented. In the present study, we determine the diel activity of two specialized pollinator weevils (Coleoptera: Curculionidae) on inflorescences of their respective host-palm: Elaeidobius kamerunicus Faust specialized on E. guineensis, and Grasidius hybridus O'Brien and Beserra specialized on E. oleifera. The average timing of activity was studied by using passive interception traps. Then the pattern and the duration were refined by using aspiration trapping within the active period for each insect species at the male and female inflorescences. All the experiments were conducted in an Ecuadorian oil palm plantation, located close to Amazonian forest. El. kamerunicus and G. hybridus were found to be the pollinators of E. guineensis and E. oleifera, respectively. The two species differed in their diel pattern of activity: E. kamerunicus was active in the morning and G. hybridus during a short period at dusk. For both palm species, insect visits were synchronous on both male and female inflorescences. The synchronicity is discussed as a strategy to maintain the relation mutualistic between partners. These findings increase our understanding of the oil palm pollination system.

  4. 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

  5. Role of biomechanics and muscle activation strategy in the production of endpoint force patterns in the cat hindlimb.

    PubMed

    Lemay, Michel A; Bhowmik-Stoker, Manoshi; McConnell, George C; Grill, Warren M

    2007-01-01

    We used a musculoskeletal model of the cat hindlimb to compare the patterns of endpoint forces generated by all possible combination of 12 hindlimb muscles under three different muscle activation rules: homogeneous activation of muscles based on uniform activation levels, homogeneous activation of muscles based on uniform (normalized) force production, and activation based on the topography of spinal motoneuron pools. Force patterns were compared with the patterns obtained experimentally by microstimulation of the lumbar spinal cord in spinal intact cats. Magnitude and orientation of the force patterns were compared, as well as the proportion of the types found, and the proportions of patterns exhibiting points of zero force (equilibrium points). The force patterns obtained with the homogenous activation and motoneuron topography models were quite similar to those measured experimentally, with the differences being larger for the patterns from the normalized endpoint forces model. Differences in the proportions of types of force patterns between the three models and the experimental results were significant for each model. Both homogeneous activation and normalized endpoint force models produced similar proportions of equilibrium points as found experimentally. The results suggest that muscle biomechanics play an important role in limiting the number of endpoint force pattern types, and that muscle combinations activated at similar levels reproduced best the experimental results obtained with intraspinal microstimulation.

  6. Cognitive and metacognitive activity in mathematical problem solving: prefrontal and parietal patterns.

    PubMed

    Anderson, John R; Betts, Shawn; Ferris, Jennifer L; Fincham, Jon M

    2011-03-01

    Students were taught an algorithm for solving a new class of mathematical problems. Occasionally in the sequence of problems, they encountered exception problems that required that they extend the algorithm. Regular and exception problems were associated with different patterns of brain activation. Some regions showed a Cognitive pattern of being active only until the problem was solved and no difference between regular or exception problems. Other regions showed a Metacognitive pattern of greater activity for exception problems and activity that extended into the post-solution period, particularly when an error was made. The Cognitive regions included some of parietal and prefrontal regions associated with the triple-code theory of (Dehaene, S., Piazza, M., Pinel, P., & Cohen, L. (2003). Three parietal circuits for number processing. Cognitive Neuropsychology, 20, 487-506) and associated with algebra equation solving in the ACT-R theory (Anderson, J. R. (2005). Human symbol manipulation within an 911 integrated cognitive architecture. Cognitive science, 29, 313-342. Metacognitive regions included the superior prefrontal gyrus, the angular gyrus of the triple-code theory, and frontopolar regions.

  7. Activation pattern of the limbic system following spatial learning under stress.

    PubMed

    Kogan, Inna; Richter-Levin, Gal

    2008-02-01

    Anatomical evidence suggests an interplay between the dorsal CA1 of the hippocampus (CA1), the basolateral amygdala (BLA) and the entorhinal cortex (EC), but their specific interactions in the context of emotional memory remain obscure. Here, we sought to elucidate the activation pattern in these areas following spatial learning under different stress conditions in the Morris water maze, using cAMP response element-binding protein (CREB) activation as a marker. Stress levels were manipulated by maintaining the water maze at one of two different temperatures: lower stress (warm water) or higher stress (cold water). Three groups of animals were tested under each condition: a Learning group, trained in the water maze with a hidden escape platform; a No-Platform group, subjected to the maze without an escape platform; and a Naïve group. To evaluate the quality of the spatial memory formed, we also tested long-term memory retention of the initial location of the platform following an interference procedure (reversal training). In the CA1 and EC, we found different CREB activation patterns for the lower- and higher-stress groups. By contrast, in the BLA a similar pattern of activation was detected under both stress levels. The data reveal a difference in the sensitivity of the memory to interference, with reversal training interference affecting the memory of the initial platform location only under the higher-stress condition. The results suggest that stress-dependent alterations in limbic system activation patterns underlie differences in the quality of the memory formed.

  8. Repetitive ritalin treatment modulates the diurnal activity pattern of young SD male rats.

    PubMed

    Algahim, Mohame Fodhl; Yang, Pamela Boi; Burau, Keith Dean; Swann, Allan Craig; Dafny, Nachum

    2010-09-01

    Attention Deficit Hyperactivity Disorder (ADHD) is a common behavioral disorder of children and is treated by psychostimulants. Psychostimulant exposure to children at the time of neuronal development can cause behavioral and physiological changes continuing during adulthood. Most of the studies on psychostimulants investigate the acute effects of the drug. The objective of this study was to investigate whether acute or chronic exposure to methylphenidate (MPD), the drug most often used to treat ADHD in children, will modulate the diurnal activity pattern of young rats. Maintaining the diurnal activity pattern is a physiological process that regulates the internal homeostasis. Dose response protocol was used to study the effect of acute and chronic MPD in four young post natal day 40 (P 40) rat groups, (each N=8), as follows: saline (control) group, and 0.6, 2.5, or 10.0 mg/kg i.p. MPD groups, respectively. The experiment was performed over 11 consecutive days of continuous locomotor activity recording using the open field assay. The data evaluation was divided into four phases as follows: acute, induction, washout and expression phases. There was a dose-dependent increase in the average locomotor activity in the first few hours post-injection. Analysis of the diurnal rhythmic pattern of locomotion in the three dose groups compared to control demonstrated that only the 10.0 mg/kg MPD elicited significant changes in diurnal pattern activity in the washout and the expression phase. In addition, this study indicated that chronic MPD treatment elicits dose dependent anticipation and/or withdrawal and behavioral sensitization.

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

    PubMed Central

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

    2015-01-01

    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

  10. Restrictive pattern on spirometry: association with cardiovascular risk and level of physical activity in asymptomatic adults

    PubMed Central

    Sperandio, Evandro Fornias; Arantes, Rodolfo Leite; Matheus, Agatha Caveda; da Silva, Rodrigo Pereira; Lauria, Vinícius Tonon; Romiti, Marcello; Gagliardi, Antônio Ricardo de Toledo; Dourado, Victor Zuniga

    2016-01-01

    Objective : To determine whether a restrictive pattern on spirometry is associated with the level of physical activity in daily life (PADL), as well as with cardiovascular disease (CVD) risk factors, in asymptomatic adults. Methods : A total of 374 participants (mean age, 41 ± 14 years) underwent spirometry, which included the determination of FVC and FEV1. A restrictive pattern on spirometry was defined as an FEV1/FVC ratio > 0.7 and an FVC < 80% of the predicted value. After conducting demographic, anthropometric, and CVD risk assessments, we evaluated body composition, muscle function, and postural balance, as well as performing cardiopulmonary exercise testing and administering the six-minute walk test. The PADL was quantified with a triaxial accelerometer. Results : A restrictive pattern on spirometry was found in 10% of the subjects. After multivariate logistic regression, adjusted for confounders (PADL and cardiorespiratory fitness), the following variables retained significance (OR; 95% CI) as predictors of a restrictive pattern: systemic arterial hypertension (17.5; 1.65-184.8), smoking (11.6; 1.56-87.5), physical inactivity (8.1; 1.43-46.4), larger center-of-pressure area while standing on a force platform (1.34; 1.05-1.71); and dyslipidemia (1.89; 1.12-1.98). Conclusions : A restrictive pattern on spirometry appears to be common in asymptomatic adults. We found that CVD risk factors, especially systemic arterial hypertension, smoking, and physical inactivity, were directly associated with a restrictive pattern, even when the analysis was adjusted for PADL and cardiorespiratory fitness. Longitudinal studies are needed in order to improve understanding of the etiology of a restrictive pattern as well as to aid in the design of preventive strategies. PMID:26982037

  11. Psychological Well-Being (PWB) of School Adolescents Aged 12–18 yr, its Correlation with General Levels of Physical Activity (PA) and Socio-Demographic Factors In Gilgit, Pakistan

    PubMed Central

    KHAN, Yasmin; TAGHDISI, Muhammad Hussain; NOURIJELYANI, Keramat

    2015-01-01

    Background: Adolescence is a critical developmental stage marked by complex transitions. The purpose of study was to assess school adolescents’ PWB, examine the relationship of PA and socio-demographic factors with PWB. Methods: A cross sectional study conducted in five randomly selected schools with 345 adolescents (aged 12–18) from grade 6th–10th. A self-administered Well-Being index was adapted to measure PWB and questionnaire for adolescents PA (PAQ-A). Socio-demographic variables determined: age, gender, household income and parental education. Bivariate and multivariate regression analyses performed to examine the association between PWB, PA and covariates. Results: Findings indicated the mean age 14.64 (SD=1.275), 55.4% were female. Without gender difference the majority (43.4%) of adolescents showed moderate, while (23.2%) revealed low level of PWB. Participants with low level likely to have depression but scores were significantly not different between low, moderate and high PWB with PA. Socio-demographic trends of adolescents’ were observed significant (P <0.005) for PWB. In multivariable analysis the mean wellbeing in females adjusted for other covariates was significant (P =0.004) than males. PWB importantly (P <0.001) decreased by 3.36 units as its covariates increased and PA score in boys found 0.05 unit more than girls. Conclusion: The study results are invaluable in addressing low, moderate and high levels of PWB. Inadequate PA and PWB decreasing with some socio-demographic covariates is crucial health issue among female adolescents in Pakistan. Further studies need to find barrier, social indicators of PWB and implication of health among adolescents. PMID:26258093

  12. EDITORIAL: Adaptive and active materials: Selected papers from the ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 10) (Philadelphia, PA, USA, 28 September-1 October 2010) Adaptive and active materials: Selected papers from the ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 10) (Philadelphia, PA, USA, 28 September-1 October 2010)

    NASA Astrophysics Data System (ADS)

    Brei, Diann

    2011-09-01

    The third annual meeting of the AMSE/AIAA Smart Materials, Adaptive Structures and Intelligent Systems Conference (SMASIS) took place in the heart of historic Philadelphia's cultural district, and included a pioneer banquet in the National Constitutional Center. The applications emphasis of the 2010 conference was reflected in keynote talks by Dr Alan Taub, vice president of General Motors global research and development, 'Smart materials in the automotive industry'; Dr Charles R Farrar, engineering institute leader at Los Alamos National Laboratory, 'Future directions for structural health monitoring of civil engineering infrastructure'; and Professor Christopher S Lynch of the University of California Los Angeles, 'Ferroelectric materials and their applications'. The SMASIS conference was divided into six technical symposia each of which included basic research, applied technological design and development, and industrial and governmental integrated system and application demonstrations. The six symposia were: SYMP 1 Multifunctional Materials; SYMP 2 Active Materials, Mechanics and Behavior; SYMP 3 Modeling, Simulation and Control; SYMP 4 Enabling Technologies and Integrated System Design; SYMP 5 Structural Health Monitoring/NDE; and SYMP 6 Bio-inspired Smart Materials and Structures. In addition, the conference introduced a new student and young professional development symposium. Authors of papers in the materials areas (symposia 1, 2 and 6) were invited to write a full journal article on their presentation topic for publication in this special issue of Smart Materials and Structures. This set of papers demonstrates the exceptional quality and originality of the conference presentations. We are appreciative of their efforts in producing this collection of highly relevant articles on smart materials.

  13. Temporal pattern of acoustic imaging noise asymmetrically modulates activation in the auditory cortex.

    PubMed

    Ranaweera, Ruwan D; Kwon, Minseok; Hu, Shuowen; Tamer, Gregory G; Luh, Wen-Ming; Talavage, Thomas M

    2016-01-01

    This study investigated the hemisphere-specific effects of the temporal pattern of imaging related acoustic noise on auditory cortex activation. Hemodynamic responses (HDRs) to five temporal patterns of imaging noise corresponding to noise generated by unique combinations of imaging volume and effective repetition time (TR), were obtained using a stroboscopic event-related paradigm with extra-long (≥27.5 s) TR to minimize inter-acquisition effects. In addition to confirmation that fMRI responses in auditory cortex do not behave in a linear manner, temporal patterns of imaging noise were found to modulate both the shape and spatial extent of hemodynamic responses, with classically non-auditory areas exhibiting responses to longer duration noise conditions. Hemispheric analysis revealed the right primary auditory cortex to be more sensitive than the left to the presence of imaging related acoustic noise. Right primary auditory cortex responses were significantly larger during all the conditions. This asymmetry of response to imaging related acoustic noise could lead to different baseline activation levels during acquisition schemes using short TR, inducing an observed asymmetry in the responses to an intended acoustic stimulus through limitations of dynamic range, rather than due to differences in neuronal processing of the stimulus. These results emphasize the importance of accounting for the temporal pattern of the acoustic noise when comparing findings across different fMRI studies, especially those involving acoustic stimulation.

  14. Temporal pattern of acoustic imaging noise asymmetrically modulates activation in the auditory cortex

    PubMed Central

    Ranaweera, Ruwan D.; Kwon, Minseok; Hu, Shuowen; Tamer, Gregory G.; Luh, Wen-Ming; Talavage, Thomas M.

    2015-01-01

    This study investigated the hemisphere-specific effects of the temporal pattern of imaging related acoustic noise on auditory cortex activation. Hemodynamic responses (HDRs) to five temporal patterns of imaging noise corresponding to noise generated by unique combinations of imaging volume and effective repetition time (TR), were obtained using a stroboscopic event-related paradigm with extra-long (≥27.5s) TR to minimize inter-acquisition effects. In addition to confirmation that fMRI responses in auditory cortex do not behave in a linear manner, temporal patterns of imaging noise were found to modulate both the shape and spatial extent of hemodynamic responses, with classically non-auditory areas exhibiting responses to longer duration noise conditions. Hemispheric analysis revealed the right primary auditory cortex to be more sensitive than the left to the presence of imaging related acoustic noise. Right primary auditory cortex responses were significantly larger during all the conditions. This asymmetry of response to imaging related acoustic noise could lead to different baseline activation levels during acquisition schemes using short TR, inducing an observed asymmetry in the responses to an intended acoustic stimulus through limitations of dynamic range, rather than due to differences in neuronal processing of the stimulus. These results emphasize the importance of accounting for the temporal pattern of the acoustic noise when comparing findings across different fMRI studies, especially those involving acoustic stimulation. PMID:26519093

  15. Evaluation of friction enhancement through soft polymer micro-patterns in active capsule endoscopy

    NASA Astrophysics Data System (ADS)

    Buselli, Elisa; Pensabene, Virginia; Castrataro, Piero; Valdastri, Pietro; Menciassi, Arianna; Dario, Paolo

    2010-10-01

    Capsule endoscopy is an emerging field in medical technology. Despite very promising innovations, some critical issues are yet to be addressed, such as the management and possible exploitation of the friction in the gastrointestinal environment in order to control capsule locomotion more actively. This paper presents the fabrication and testing of bio-inspired polymeric micro-patterns, which are arrays of cylindrical pillars fabricated via soft lithography. The aim of the work is to develop structures that enhance the grip between an artificial device and the intestinal tissue, without injuring the mucosa. In fact, the patterns are intended to be mounted on microfabricated legs of a capsule robot that is able to move actively in the gastrointestinal tract, thus improving the robot's traction ability. The effect of micro-patterned surfaces on the leg-slipping behaviour on colon walls was investigated by considering both different pillar dimensions and the influence of tissue morphology. Several in vitro tests on biological samples demonstrated that micro-patterns of pillars made from a soft polymer with an aspect ratio close to 1 enhanced friction by 41.7% with regard to flat surfaces. This work presents preliminary modelling of the friction and adhesion forces in the gastrointestinal environment and some design guidelines for endoscopic devices.

  16. Macro-Scale Patterns in Upwelling/Downwelling Activity at North American West Coast

    PubMed Central

    Saldívar-Lucio, Romeo; Di Lorenzo, Emanuele; Nakamura, Miguel; Villalobos, Héctor; Lluch-Cota, Daniel; Del Monte-Luna, Pablo

    2016-01-01

    The seasonal and interannual variability of vertical transport (upwelling/downwelling) has been relatively well studied, mainly for the California Current System, including low-frequency changes and latitudinal heterogeneity. The aim of this work was to identify potentially predictable patterns in upwelling/downwelling activity along the North American west coast and discuss their plausible mechanisms. To this purpose we applied the min/max Autocorrelation Factor technique and time series analysis. We found that spatial co-variation of seawater vertical movements present three dominant low-frequency signals in the range of 33, 19 and 11 years, resembling periodicities of: atmospheric circulation, nodal moon tides and solar activity. Those periodicities might be related to the variability of vertical transport through their influence on dominant wind patterns, the position/intensity of pressure centers and the strength of atmospheric circulation cells (wind stress). The low-frequency signals identified in upwelling/downwelling are coherent with temporal patterns previously reported at the study region: sea surface temperature along the Pacific coast of North America, catch fluctuations of anchovy Engraulis mordax and sardine Sardinops sagax, the Pacific Decadal Oscillation, changes in abundance and distribution of salmon populations, and variations in the position and intensity of the Aleutian low. Since the vertical transport is an oceanographic process with strong biological relevance, the recognition of their spatio-temporal patterns might allow for some reasonable forecasting capacity, potentially useful for marine resources management of the region. PMID:27893826

  17. Macro-Scale Patterns in Upwelling/Downwelling Activity at North American West Coast.

    PubMed

    Saldívar-Lucio, Romeo; Di Lorenzo, Emanuele; Nakamura, Miguel; Villalobos, Héctor; Lluch-Cota, Daniel; Del Monte-Luna, Pablo

    2016-01-01

    The seasonal and interannual variability of vertical transport (upwelling/downwelling) has been relatively well studied, mainly for the California Current System, including low-frequency changes and latitudinal heterogeneity. The aim of this work was to identify potentially predictable patterns in upwelling/downwelling activity along the North American west coast and discuss their plausible mechanisms. To this purpose we applied the min/max Autocorrelation Factor technique and time series analysis. We found that spatial co-variation of seawater vertical movements present three dominant low-frequency signals in the range of 33, 19 and 11 years, resembling periodicities of: atmospheric circulation, nodal moon tides and solar activity. Those periodicities might be related to the variability of vertical transport through their influence on dominant wind patterns, the position/intensity of pressure centers and the strength of atmospheric circulation cells (wind stress). The low-frequency signals identified in upwelling/downwelling are coherent with temporal patterns previously reported at the study region: sea surface temperature along the Pacific coast of North America, catch fluctuations of anchovy Engraulis mordax and sardine Sardinops sagax, the Pacific Decadal Oscillation, changes in abundance and distribution of salmon populations, and variations in the position and intensity of the Aleutian low. Since the vertical transport is an oceanographic process with strong biological relevance, the recognition of their spatio-temporal patterns might allow for some reasonable forecasting capacity, potentially useful for marine resources management of the region.

  18. Learning new gait patterns: Exploratory muscle activity during motor learning is not predicted by motor modules.

    PubMed

    Ranganathan, Rajiv; Krishnan, Chandramouli; Dhaher, Yasin Y; Rymer, William Z

    2016-03-21

    The motor module hypothesis in motor control proposes that the nervous system can simplify the problem of controlling a large number of muscles in human movement by grouping muscles into a smaller number of modules. Here, we tested one prediction of the modular organization hypothesis by examining whether there is preferential exploration along these motor modules during the learning of a new gait pattern. Healthy college-aged participants learned a new gait pattern which required increased hip and knee flexion during the swing phase while walking in a lower-extremity robot (Lokomat). The new gait pattern was displayed as a foot trajectory in the sagittal plane and participants attempted to match their foot trajectory to this template. We recorded EMG from 8 lower-extremity muscles and we extracted motor modules during both baseline walking and target-tracking using non-negative matrix factorization (NMF). Results showed increased trajectory variability in the first block of learning, indicating that participants were engaged in exploratory behavior. Critically, when we examined the muscle activity during this exploratory phase, we found that the composition of motor modules changed significantly within the first few strides of attempting the new gait pattern. The lack of persistence of the motor modules under even short time scales suggests that motor modules extracted during locomotion may be more indicative of correlated muscle activity induced by the task constraints of walking, rather than reflecting a modular control strategy.

  19. Fetal Functional Brain Age Assessed from Universal Developmental Indices Obtained from Neuro-Vegetative Activity Patterns

    PubMed Central

    Hoyer, Dirk; Tetschke, Florian; Jaekel, Susan; Nowack, Samuel; Witte, Otto W.; Schleußner, Ekkehard; Schneider, Uwe

    2013-01-01

    Fetal brain development involves the development of the neuro-vegetative (autonomic) control that is mediated by the autonomic nervous system (ANS). Disturbances of the fetal brain development have implications for diseases in later postnatal life. In that context, the fetal functional brain age can be altered. Universal principles of developmental biology applied to patterns of autonomic control may allow a functional age assessment. The work aims at the development of a fetal autonomic brain age score (fABAS) based on heart rate patterns. We analysed n = 113 recordings in quiet sleep, n = 286 in active sleep, and n = 29 in active awakeness from normals. We estimated fABAS from magnetocardiographic recordings (21.4–40.3 weeks of gestation) preclassified in quiet sleep (n = 113, 63 females) and active sleep (n = 286, 145 females) state by cross-validated multivariate linear regression models in a cross-sectional study. According to universal system developmental principles, we included indices that address increasing fluctuation range, increasing complexity, and pattern formation (skewness, power spectral ratio VLF/LF, pNN5). The resulting models constituted fABAS. fABAS explained 66/63% (coefficient of determination R2 of training and validation set) of the variance by age in quiet, while 51/50% in active sleep. By means of a logistic regression model using fluctuation range and fetal age, quiet and active sleep were automatically reclassified (94.3/93.1% correct classifications). We did not find relevant gender differences. We conclude that functional brain age can be assessed based on universal developmental indices obtained from autonomic control patterns. fABAS reflect normal complex functional brain maturation. The presented normative data are supplemented by an explorative study of 19 fetuses compromised by intrauterine growth restriction. We observed a shift in the state distribution towards active awakeness. The lower WGA dependent f

  20. Activity patterns and synaptic organization of ventrally located interneurons in the embryonic chick spinal cord.

    PubMed

    Ritter, A; Wenner, P; Ho, S; Whelan, P J; O'Donovan, M J

    1999-05-01

    To investigate the origin of spontaneous activity in developing spinal networks, we examined the activity patterns and synaptic organization of ventrally located lumbosacral interneurons, including those whose axons project into the ventrolateral funiculus (VLF), in embryonic day 9 (E9)-E12 chick embryos. During spontaneous episodes, rhythmic synaptic potentials were recorded from the VLF and from spinal interneurons that were synchronized, cycle by cycle, with rhythmic ventral root potentials. At the beginning of an episode, ventral root potentials started before the VLF discharge and the firing of individual interneurons. However, pharmacological blockade of recurrent motoneuron collaterals did not prevent or substantially delay interneuron recruitment during spontaneous episodes. The synaptic connections of interneurons were examined by stimulating the VLF and recording the potentials evoked in the ventral roots, in the VLF, or in individual interneurons. Low-intensity stimulation of the VLF evoked a short-latency depolarizing potential in the ventral roots, or in interneurons, that was probably mediated mono- or disynaptically. At higher intensities, long-latency responses were recruited in a highly nonlinear manner, eventually culminating in the activation of an episode. VLF-evoked potentials were reversibly blocked by extracellular Co2+, indicating that they were mediated by chemical synaptic transmission. Collectively, these findings indicate that ventral interneurons are rhythmically active, project to motoneurons, and are likely to be interconnected by recurrent excitatory synaptic connections. This pattern of organization may explain the synchronous activation of spinal neurons and the regenerative activation of spinal networks when provided with a suprathreshold stimulus.

  1. Patterns of Bat Distribution and Foraging Activity in a Highly Urbanized Temperate Environment

    PubMed Central

    2016-01-01

    Understanding how to manage biodiversity in urban areas will become increasingly important as density of humans residing in urban centers increases and urban areas expand. While considerable research has documented the shifts in biodiversity along urbanization gradients, much less work has focused on how characteristics of dense urban centers, effectively novel environments, influence behavior and biodiversity. Urban bats in San Francisco provide an opportunity to document changes in behavior and biodiversity to very high-density development. We studied (1) the distribution and abundance of bat foraging activity in natural areas; and (2) characteristics of natural areas that influence the observed patterns of distribution and foraging activity. We conducted acoustic surveys of twenty-two parks during 2008–2009. We confirmed the presence of four species of bats (Tadarida brasiliensis, Myotis yumanensis, Lasiurus blossevillii, and M. lucifugus). T. brasiliensis were found in all parks, while M. yumanensis occurred in 36% of parks. Results indicate that proximity to water, park size, and amount of forest edge best explained overall foraging activity. Proximity to water best explained species richness. M. yumanensis activity was best explained by reduced proportion of native vegetation as well as proximity to water. Activity was year round but diminished in December. We show that although bats are present even in very densely populated urban centers, there is a large reduction in species richness compared to that of outlying areas, and that most habitat factors explaining their community composition and activity patterns are similar to those documented in less urbanized environments. PMID:28030640

  2. Patterns of Bat Distribution and Foraging Activity in a Highly Urbanized Temperate Environment.

    PubMed

    Krauel, Jennifer J; LeBuhn, Gretchen

    2016-01-01

    Understanding how to manage biodiversity in urban areas will become increasingly important as density of humans residing in urban centers increases and urban areas expand. While considerable research has documented the shifts in biodiversity along urbanization gradients, much less work has focused on how characteristics of dense urban centers, effectively novel environments, influence behavior and biodiversity. Urban bats in San Francisco provide an opportunity to document changes in behavior and biodiversity to very high-density development. We studied (1) the distribution and abundance of bat foraging activity in natural areas; and (2) characteristics of natural areas that influence the observed patterns of distribution and foraging activity. We conducted acoustic surveys of twenty-two parks during 2008-2009. We confirmed the presence of four species of bats (Tadarida brasiliensis, Myotis yumanensis, Lasiurus blossevillii, and M. lucifugus). T. brasiliensis were found in all parks, while M. yumanensis occurred in 36% of parks. Results indicate that proximity to water, park size, and amount of forest edge best explained overall foraging activity. Proximity to water best explained species richness. M. yumanensis activity was best explained by reduced proportion of native vegetation as well as proximity to water. Activity was year round but diminished in December. We show that although bats are present even in very densely populated urban centers, there is a large reduction in species richness compared to that of outlying areas, and that most habitat factors explaining their community composition and activity patterns are similar to those documented in less urbanized environments.

  3. 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.

  4. Probable nature of higher-dimensional symmetries underlying mammalian grid-cell activity patterns.

    PubMed

    Mathis, Alexander; Stemmler, Martin B; Herz, Andreas Vm

    2015-04-24

    Lattices abound in nature-from the crystal structure of minerals to the honey-comb organization of ommatidia in the compound eye of insects. These arrangements provide solutions for optimal packings, efficient resource distribution, and cryptographic protocols. Do lattices also play a role in how the brain represents information? We focus on higher-dimensional stimulus domains, with particular emphasis on neural representations of physical space, and derive which neuronal lattice codes maximize spatial resolution. For mammals navigating on a surface, we show that the hexagonal activity patterns of grid cells are optimal. For species that move freely in three dimensions, a face-centered cubic lattice is best. This prediction could be tested experimentally in flying bats, arboreal monkeys, or marine mammals. More generally, our theory suggests that the brain encodes higher-dimensional sensory or cognitive variables with populations of grid-cell-like neurons whose activity patterns exhibit lattice structures at multiple, nested scales.

  5. Geographic Variation in Daily Temporal Activity Patterns of a Neotropical Marsupial (Gracilinanus agilis).

    PubMed

    Vieira, Emerson M; de Camargo, Nícholas F; Colas, Paul F; Ribeiro, Juliana F; Cruz-Neto, Ariovaldo P

    2017-01-01

    The temporal activity of animals is an outcome of both biotic and abiotic factors, which may vary along the geographic range of the species. Therefore, studies conducted with a species in different localities with distinct features could elucidate how animals deal with such factors. In this study, we used live traps equipped with timing devices to investigate the temporal activity patterns of the didelphid Gracilinanus agilis in two dry-woodland areas of the Brazilian savanna (Cerrado). These areas were located about 660 km apart, one in Central Brazil and the other in Southeastern Brazil. We compared such patterns considering both reproductive and non-reproductive periods, and how it varies as a function of temperature on a seasonal basis. In Central Brazil, we found a constant, and temperature-independent activity during the night in both reproductive and non-reproductive periods. On the other hand, in Southeastern Brazil, we detected a constant activity during the reproductive period, but in the non-reproductive period G. agilis presented a peak of activity between two and four hours after sunset. Moreover, in this latter we found a relation between temporal activity and temperature during the autumn and spring. These differences in temporal activity between areas, observed during the non-reproductive period, might be associated with the higher seasonal variability in temperature, and lower mean temperatures in the Southeastern site in comparison to the Central one. In Southeastern Brazil, the decrease in temperature during the non-reproductive season possibly forced G. agilis to be active only at certain hours of the night. However, likely due to the reproductive activities (intensive foraging and searching for mates) this marsupial showed constant, temperature-independent activity during the night in the reproductive period at both sites.

  6. Geographic Variation in Daily Temporal Activity Patterns of a Neotropical Marsupial (Gracilinanus agilis)

    PubMed Central

    Vieira, Emerson M.; de Camargo, Nícholas F.; Colas, Paul F.; Ribeiro, Juliana F.; Cruz-Neto, Ariovaldo P.

    2017-01-01

    The temporal activity of animals is an outcome of both biotic and abiotic factors, which may vary along the geographic range of the species. Therefore, studies conducted with a species in different localities with distinct features could elucidate how animals deal with such factors. In this study, we used live traps equipped with timing devices to investigate the temporal activity patterns of the didelphid Gracilinanus agilis in two dry-woodland areas of the Brazilian savanna (Cerrado). These areas were located about 660 km apart, one in Central Brazil and the other in Southeastern Brazil. We compared such patterns considering both reproductive and non-reproductive periods, and how it varies as a function of temperature on a seasonal basis. In Central Brazil, we found a constant, and temperature-independent activity during the night in both reproductive and non-reproductive periods. On the other hand, in Southeastern Brazil, we detected a constant activity during the reproductive period, but in the non-reproductive period G. agilis presented a peak of activity between two and four hours after sunset. Moreover, in this latter we found a relation between temporal activity and temperature during the autumn and spring. These differences in temporal activity between areas, observed during the non-reproductive period, might be associated with the higher seasonal variability in temperature, and lower mean temperatures in the Southeastern site in comparison to the Central one. In Southeastern Brazil, the decrease in temperature during the non-reproductive season possibly forced G. agilis to be active only at certain hours of the night. However, likely due to the reproductive activities (intensive foraging and searching for mates) this marsupial showed constant, temperature-independent activity during the night in the reproductive period at both sites. PMID:28052077

  7. Patterns of Spontaneous Local Network Activity in Developing Cerebral Cortex: Relationship to Adult Cognitive Function.

    PubMed

    Peinado, Alejandro; Abrams, Charles K

    2015-01-01

    Detecting neurodevelopμental disorders of cognition at the earliest possible stages could assist in understanding them mechanistically and ultimately in treating them. Finding early physiological predictors that could be visualized with functional neuroimaging would represent an important advance in this regard. We hypothesized that one potential source of physiological predictors is the spontaneous local network activity prominent during specific periods in development. To test this we used calcium imaging in brain slices and analyzed variations in the frequency and intensity of this early activity in one area, the entorhinal cortex (EC), in order to correlate early activity with level of cognitive function later in life. We focused on EC because of its known role in different types of cognitive processes and because it is an area where spontaneous activity is prominent during early postnatal development in rodent models of cortical development. Using rat strains (Long-Evans, Wistar, Sprague-Dawley and Brattleboro) known to differ in cognitive performance in adulthood we asked whether neonatal animals exhibit corresponding strain-related differences in EC spontaneous activity. Our results show significant differences in this activity between strains: compared to a high cognitive-performing strain, we consistently found an increase in frequency and decrease in intensity in neonates from three lower performing strains. Activity was most different in one strain considered a model of schizophrenia-like psychopathology. While we cannot necessarily infer a causal relationship between early activity and adult cognition our findings suggest that the pattern of spontaneous activity in development could be an early predictor of a developmental trajectory advancing toward sub-optimal cognitive performance in adulthood. Our results further suggest that the strength of dopaminergic signaling, by setting the balance between excitation and inhibition, is a potential underlying

  8. Efficacy of histotripsy combined with rt-PA in vitro

    NASA Astrophysics Data System (ADS)

    Bader, Kenneth B.; Haworth, Kevin J.; Shekhar, Himanshu; Maxwell, Adam D.; Peng, Tao; McPherson, David D.; Holland, Christy K.

    2016-07-01

    Histotripsy, a form of therapeutic ultrasound that uses the mechanical action of microbubble clouds for tissue ablation, is under development to treat chronic deep vein thrombosis (DVT). We hypothesize that combining thrombolytic agents with histotripsy will enhance clot lysis. Recombinant tissue plasminogen activator (rt-PA) and rt-PA-loaded echogenic liposomes that entrain octafluoropropane microbubbles (OFP t-ELIP) were used in combination with highly shocked histotripsy pulses. Fully retracted porcine venous clots, with similar features of DVT occlusions, were exposed either to histotripsy pulses alone (peak negative pressures of 7-20 MPa), histotripsy and OFP t-ELIP, or histotripsy and rt-PA. Microbubble cloud activity was monitored with passive cavitation imaging during histotripsy exposure. The power levels of cavitation emissions from within the clot were not statistically different between treatment types, likely due to the near instantaneous rupture and destruction of OFP t-ELIP. The thrombolytic efficacy was significantly improved in the presence of rt-PA. These results suggest the combination of histotripsy and rt-PA could serve as a potent therapeutic strategy for the treatment of DVT.

  9. Activity Patterns of Eurasian Lynx Are Modulated by Light Regime and Individual Traits over a Wide Latitudinal Range

    PubMed Central

    Heurich, Marco; Hilger, Anton; Küchenhoff, Helmut; Andrén, Henrik; Bufka, Luděk; Krofel, Miha; Mattisson, Jenny; Odden, John; Persson, Jens; Rauset, Geir R.; Schmidt, Krzysztof; Linnell, John D. C.

    2014-01-01

    The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49°7′N in central Europe to 70°00′N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day–night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey. PMID:25517902

  10. Activity patterns of Eurasian lynx are modulated by light regime and individual traits over a wide latitudinal range.

    PubMed

    Heurich, Marco; Hilger, Anton; Küchenhoff, Helmut; Andrén, Henrik; Bufka, Luděk; Krofel, Miha; Mattisson, Jenny; Odden, John; Persson, Jens; Rauset, Geir R; Schmidt, Krzysztof; Linnell, John D C

    2014-01-01

    The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49°7'N in central Europe to 70°00'N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day-night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey.

  11. Muscle activation patterns and motor anatomy of Anna's hummingbirds Calypte anna and zebra finches Taeniopygia guttata.

    PubMed

    Donovan, Edward R; Keeney, Brooke K; Kung, Eric; Makan, Sirish; Wild, J Martin; Altshuler, Douglas L

    2013-01-01

    Flying animals exhibit profound transformations in anatomy, physiology, and neural architecture. Although much is known about adaptations in the avian skeleton and musculature, less is known about neuroanatomy and motor unit integration for bird flight. Hummingbirds are among the most maneuverable and specialized of vertebrate fliers, and two unusual neuromuscular features have been previously reported: (1) the pectoralis major has a unique distribution pattern of motor end plates (MEPs) compared with all other birds and (2) electromyograms (EMGs) from the hummingbird's pectoral muscles, the pectoralis major and the supracoracoideus, show activation bursts composed of one or a few spikes that appear to have a very consistent pattern. Here, we place these findings in a broader context by comparing the MEPs, EMGs, and organization of the spinal motor neuron pools of flight muscles of Anna's hummingbird Calypte anna, zebra finches Taeniopygia guttata, and, for MEPs, several other species. The previously shown MEP pattern of the hummingbird pectoralis major is not shared with its closest taxonomic relative, the swift, and appears to be unique to hummingbirds. MEP arrangements in previously undocumented wing muscles show patterns that differ somewhat from other avian muscles. In the parallel-fibered strap muscles of the shoulder, MEP patterns appear to relate to muscle length, with the smallest muscles having fibers that span the entire muscle. MEP patterns in pennate distal wing muscles were the same regardless of size, with tightly clustered bands in the middle portion of the muscle, not evenly distributed bands over the muscle's entire length. Muscle activations were examined during slow forward flight in both species, during hovering in hummingbirds, and during slow ascents in zebra finches. The EMG bursts of a wing muscle, the pronator superficialis, were highly variable in peak number, size, and distribution across wingbeats for both species. In the pectoralis

  12. Acute caffeine administration effect on brain activation patterns in mild cognitive impairment.

    PubMed

    Haller, Sven; Montandon, Marie-Louise; Rodriguez, Cristelle; Moser, Dominik; Toma, Simona; Hofmeister, Jeremy; Sinanaj, Indrit; Lovblad, Karl-Olof; Giannakopoulos, Panteleimon

    2014-01-01

    Previous studies showed that acute caffeine administration enhances task-related brain activation in elderly individuals with preserved cognition. To explore the effects of this widely used agent on cognition and brain activation in early phases of cognitive decline, we performed a double-blinded, placebo-controlled functional magnetic resonance imaging (fMRI) study during an n-back working memory task in 17 individuals with mild cognitive impairment (MCI) compared to 17 age-matched healthy controls (HC). All individuals were regular caffeine consumers with an overnight abstinence and given 200 mg caffeine versus placebo tablets 30 minutes before testing. Analyses included assessment of task-related activation (general linear model), functional connectivity (tensorial-independent component analysis, TICA), baseline perfusion (arterial spin labeling, ASL), grey matter density (voxel-based morphometry, VBM), and white matter microstructure (tract-based spatial statistics, TBSS). Acute caffeine administration induced a focal activation of the prefrontal areas in HC with a more diffuse and posteromedial activation pattern in MCI individuals. In MCI, TICA documented a significant caffeine-related enhancement in the prefrontal cortex, supplementary motor area, ventral premotor and parietal cortex as well as the basal ganglia and cerebellum. The absence of significant group differences in baseline ASL perfusion patterns supports a neuronal rather than a purely vascular origin of these differences. The VBM and TBSS analyses excluded potentially confounding differences in grey matter density and white matter microstructure between MCI and HC. The present findings suggest a posterior displacement of working memory-related brain activation patterns after caffeine administration in MCI that may represent a compensatory mechanism to counterbalance a frontal lobe dysfunction.

  13. Activation Pattern of Lower Leg Muscles in Running on Asphalt, Gravel and Grass.

    PubMed

    Dolenec, Aleš; Štirn, Igor; Strojnik, Vojko

    2015-07-01

    Running is performed on different natural surfaces (outdoor) and artificial surfaces (indoor). Different surface characteristics cause modification of the lower leg muscle activation pattern to adopt ankle stiffness to these characteristics. So the purpose of our investigation was to study changes of lower leg muscles activation pattern in running on different natural running surfaces. Six male and two female runners participated. The participants ran at a freely chosen velocity in trials on asphalt while in trials on gravel, and grass surfaces they were attempting to reach similar velocities as in the trials on asphalt. Muscle activation of the peroneus brevis, tibialis anterior, soleus, and gastrocnemius medialis of the right leg was recorded. Running on asphalt increased average EMG amplitude of the m. tibialis anterior in the pre-activation phase and the m. gastrocnemius medialis in the entire contact phase compared to running on grass from 0.222 ± 0.113 V to 0.276 ± 0.136 V and from 0.214 ± 0.084 V to 0.238 ± 0.088 V, respectively. The average EMG of m. peroneus brevis in pre-activation phase increased from 0.156 ± 0.026 V to 0.184 ± 0.455 V in running on grass in comparison to running on gravel. Running on different surfaces is connected with different activation patterns of lower leg muscles. Running on asphalt requires stiff ankle joints, running on gravel requires greater stability in ankle joints, while running on grass is the least demanding on lower leg muscles.

  14. Spatiotemporal patterns of mountain pine beetle activity in the southern Rocky Mountains.

    PubMed

    Chapman, Teresa B; Veblen, Thomas T; Schoennagel, Tania

    2012-10-01

    The current mountain pine beetle (MPB; Dendroctonus ponderosae) outbreak in the southern Rocky Mountains has impacted approximately 750 000 ha of forest. Weather and habitat heterogeneity influence forest insect population dynamics at multiple spatial and temporal scales. Comparison of forest insect population dynamics in two principal host species may elucidate the relative contribution of weather and landscape factors in initiating and driving extensive outbreaks. To investigate potential drivers of the current MPB outbreak, we compared broadscale spatiotemporal patterns of MPB activity in lodgepole pine (Pinus contorta) and ponderosa pine (Pinus ponderosa) from 1996 to 2010 in Colorado and southern Wyoming with regional weather fluctuations, and then tracked the annual meso-scale progression of the epidemic in lodgepole pine with respect to weather, topographic, previous MPB activity, and forest stand attributes. MPB activity in lodgepole pine compared to ponderosa pine showed higher magnitude and extent of spatial synchrony. Warm temperatures and low annual precipitation favorable to beetle populations showed high regional synchrony across areas of both pine species, suggesting that habitat interacts with weather in synchronizing MPB populations. Cluster analysis of time series patterns identified multiple, disjunct locations of incipient MPB activity (epicenters) in lodgepole pine, which overlapped an earlier 1980s MPB outbreak, and suggests a regional trigger (drought) across this homogenous forest type. Negative departures from mean annual precipitation played a key role in subsequent spread of MPB outbreak. Development of the outbreak was also associated with lower elevations, greater dominance by lodgepole pine, stands of larger tree size, and stands with higher percentage canopy cover. After epidemic levels of MPB activity were attained, MPB activity was less strongly associated with stand and weather variables. These results emphasize the importance of

  15. Diel patterns in sea urchin activity and predation on sea urchins on the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    Young, M. A. L.; Bellwood, D. R.

    2011-09-01

    Understanding diel patterns in sea urchin activity is important when assessing sea urchin populations and when interpreting their interactions with predators. Here we employ a combination of surveys and a non-invasive tethering technique to examine these patterns in an intact coral reef system on the Great Barrier Reef (GBR). We also assess local scale variation in relative diurnal predation pressure. Surveys revealed that sea urchins were active and exposed at night. Echinometra mathaei and Echinothrix calamaris were the most abundant species with significantly higher night densities (0.21 and 0.03 ind. m-2, respectively), than daytime densities (0.05 and 0.001, respectively). Bioassays revealed that exposed adult E. mathaei (the most abundant sea urchin species) were 30.8 times more likely to be eaten during the day than at night when controlling for sites. This observation concurs with widely held assumptions that nocturnal activity is a risk-related adaptive response to diurnal predation pressure. Despite relatively intact predator communities on the GBR, potential predation pressure on diurnally exposed E. mathaei assays was variable at a local scale and the biomass of potential fish predators at each site was a poor predictive measure of this variation. Patterns in predation appear to be more complex and variable than we may have assumed.

  16. Diurnal-activity Patterns of the Small Bee-eater (Merops orientalis) in Southern India

    PubMed Central

    Ali, Abdul Hameed Mohamed Samsoor; Asokan, Subramanian

    2015-01-01

    The diurnal time-activity patterns of the Small Bee-eater (Merops orientalis) were studied between 2005 and 2006 in the Nagapattinam District of Southern India. Bee-eaters were observed to spend an average of 52.5% of their day time scanning, 21.3% feeding, 13.3% flying, 8.8% resting and 4.1% engaging in preening activities. The time spent on scanning varied among seasons in 2005 (p<0.05) and among time blocks (p<0.05), but it did not vary among years or habitats (p>0.05). The feeding patterns differed among years, seasons within years, time blocks and habitats (p<0.05). The flying habits varied among years, time blocks and habitats (p<0.05) but did not change between seasons within years (p>0.05). The resting habits differed among years and habitats (p<0.05) but did not differ among seasons within years or time blocks (p>0.05). Preening differed among years and time blocks (p<0.05) but did not vary among seasons within years or habitats (p>0.05). We conclude that several factors, such as food availability, environmental factors and predation threats, may affect the diurnal activity patterns of Bee-eaters between habitats and seasons; a further study could clarify this conclusion. PMID:26868589

  17. Diurnal-activity Patterns of the Small Bee-eater (Merops orientalis) in Southern India.

    PubMed

    Ali, Abdul Hameed Mohamed Samsoor; Asokan, Subramanian

    2015-04-01

    The diurnal time-activity patterns of the Small Bee-eater (Merops orientalis) were studied between 2005 and 2006 in the Nagapattinam District of Southern India. Bee-eaters were observed to spend an average of 52.5% of their day time scanning, 21.3% feeding, 13.3% flying, 8.8% resting and 4.1% engaging in preening activities. The time spent on scanning varied among seasons in 2005 (p<0.05) and among time blocks (p<0.05), but it did not vary among years or habitats (p>0.05). The feeding patterns differed among years, seasons within years, time blocks and habitats (p<0.05). The flying habits varied among years, time blocks and habitats (p<0.05) but did not change between seasons within years (p>0.05). The resting habits differed among years and habitats (p<0.05) but did not differ among seasons within years or time blocks (p>0.05). Preening differed among years and time blocks (p<0.05) but did not vary among seasons within years or habitats (p>0.05). We conclude that several factors, such as food availability, environmental factors and predation threats, may affect the diurnal activity patterns of Bee-eaters between habitats and seasons; a further study could clarify this conclusion.

  18. Diel activity patterns of major species of adult mosquitoes and ULV spraying impacts in St. John's County, Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of daily activity patterns in adult mosquitoes can be used to determine the best time to apply adulticides for mosquito control. Many factors influence these activity patterns, including migration, hormonal cycles in the mosquito, hunger, and the need to lay eggs. In this study, FL scien...

  19. Impact of variations in solar activity on hydrological decadal patterns in northern Italy

    NASA Astrophysics Data System (ADS)

    Zanchettin, D.; Rubino, A.; Traverso, P.; Tomasino, M.

    2008-06-01

    Using spectral and statistical analyses of discharges and basin average precipitation rates acquired over the Po River since the early 1800s, we investigate the impact of variations in solar activity on hydrological decadal patterns over northern Italy. Wet and dry periods appear to alternate in accordance with polarized sunspot cycles. Intriguingly, a solar signature on Po River discharges is detected to be highly significant since the late 1800s, before the onset of sunspots hyperactivity established by the middle 1900s. In particular, observed hydrological patterns over northern Italy are significantly correlated, under periods of quiet sunspot activity, with parameters characterizing the Sun's orbital motion, specifically with the time derivative of the solar angular momentum (τ) which is thought to modulate the strength of the solar wind and sunspot dynamics under weak sunspot activity. The North Atlantic Oscillation (NAO) is detected as potential link between the Sun and Po River discharges, since it is significantly correlated with both solar activity and the decadal variability in the north Italian climate. In particular, positive (negative) NAO anomalies, which are associated with comparatively lower (higher) Po River discharges, are assessed to alternatively correlate at decadal timescales either with τ or with the Earth's geomagnetic activity (GA), which closely follows sunspot activity. This changing correlation seems to be regulated by the strength of sunspot activity: under periods of quiet sunspot activity, a weakening of the GA-NAO connection and a reinforcement of the τ-NAO connection is observed. In this sense, the strength of solar activity apparently modulates the connection between the NAO and Po River discharges.

  20. Patterns and correlates of physical activity: a cross-sectional study in urban Chinese women

    PubMed Central

    Jurj, Adriana L; Wen, Wanqing; Gao, Yu-Tang; Matthews, Charles E; Yang, Gong; Li, Hong-Lan; Zheng, Wei; Shu, Xiao-Ou

    2007-01-01

    Background Inactivity is a modifiable risk factor for many diseases. Rapid economic development in China has been associated with changes in lifestyle, including physical activity. The purpose of this study was to investigate the patterns and correlates of physical activity in middle-aged and elderly women from urban Shanghai. Methods Study population consisted of 74,942 Chinese women, 40–70 years of age, participating in the baseline survey of the Shanghai Women's Health Study (1997–2000), an ongoing population-based cohort study. A validated, interviewer-administered physical activity questionnaire was used to collect information about several physical activity domains (exercise/sports, walking and cycling for transportation, housework). Correlations between physical activity domains were evaluated by Spearman rank-correlation coefficients. Associations between physical activity and socio-demographic and lifestyle factors were evaluated by odds ratios derived from logistic regression. Results While more than a third of study participants engaged in regular exercise, this form of activity contributed only about 10% to daily non-occupational energy expenditure. About two-thirds of women met current recommendations for lifestyle activity. Age was positively associated with participation in exercise/sports and housework. Dietary energy intake was positively associated with all physical activity domains. High socioeconomic status, unemployment (including retirement), history of chronic disease, small household, non-smoking status, alcohol and tea consumption, and ginseng intake were all positively associated with exercise participation. High socioeconomic status and small household were inversely associated with non-exercise activities. Conclusion This study demonstrates that physical activity domains other than sports and exercise are important contributors to total energy expenditure in women. Correlates of physical activity are domain-specific. These findings

  1. Pseudomonas aeruginosa PA1006 Is a Persulfide-Modified Protein That Is Critical for Molybdenum Homeostasis

    PubMed Central

    Tombline, Gregory; Schwingel, Johanna M.; Lapek, John D.; Friedman, Alan E.; Darrah, Thomas; Maguire, Michael; Van Alst, Nadine E.; Filiatrault, Melanie J.; Iglewski, Barbara H.

    2013-01-01

    A companion manuscript revealed that deletion of the Pseudomonas aeruginosa (Pae) PA1006 gene caused pleiotropic defects in metabolism including a loss of all nitrate reductase activities, biofilm maturation, and virulence. Herein, several complementary approaches indicate that PA1006 protein serves as a persulfide-modified protein that is critical for molybdenum homeostasis in Pae. Mutation of a highly conserved Cys22 to Ala or Ser resulted in a loss of PA1006 activity. Yeast-two-hybrid and a green-fluorescent protein fragment complementation assay (GFP-PFCA) in Pae itself revealed that PA1006 interacts with Pae PA3667/CsdA and PA3814/IscS Cys desulfurase enzymes. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) “top-down” analysis of PA1006 purified from Pae revealed that conserved Cys22 is post-translationally modified in vivo in the form a persulfide. Inductively-coupled-plasma (ICP)-MS analysis of ΔPA1006 mutant extracts revealed that the mutant cells contain significantly reduced levels of molybdenum compared to wild-type. GFP-PFCA also revealed that PA1006 interacts with several molybdenum cofactor (MoCo) biosynthesis proteins as well as nitrate reductase maturation factor NarJ and component NarH. These data indicate that a loss of PA1006 protein’s persulfide sulfur and a reduced availability of molybdenum contribute to the phenotype of a ΔPA1006 mutant. PMID:23409003

  2. 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.

  3. Lateralization of brain activity pattern during unilateral movement in Parkinson's disease.

    PubMed

    Wu, Tao; Hou, Yanan; Hallett, Mark; Zhang, Jiarong; Chan, Piu

    2015-05-01

    We investigated the lateralization of brain activity pattern during performance of unilateral movement in drug-naïve Parkinson's disease (PD) patients with only right hemiparkinsonian symptoms. Functional MRI was obtained when the subjects performed strictly unilateral right hand movement. A laterality index was calculated to examine the lateralization. Patients had decreased activity in the left putamen and left supplementary motor area, but had increased activity in the right primary motor cortex, right premotor cortex, left postcentral gyrus, and bilateral cerebellum. The laterality index was significantly decreased in PD patients compared with controls (0.41 ± 0.14 vs. 0.84 ± 0.09). The connectivity from the left putamen to cortical motor regions and cerebellum was decreased, while the interactions between the cortical motor regions, cerebellum, and right putamen were increased. Our study demonstrates that in early PD, the lateralization of brain activity during unilateral movement is significantly reduced. The dysfunction of the striatum-cortical circuit, decreased transcallosal inhibition, and compensatory efforts from cortical motor regions, cerebellum, and the less affected striatum are likely reasons contributing to the reduced motor lateralization. The disruption of the lateralized brain activity pattern might be a reason underlying some motor deficits in PD, like mirror movements or impaired bilateral motor coordination.

  4. Sensory-induced activation of pattern generators in the absence of supraspinal control.

    PubMed

    Lev-Tov, A; Etlin, A; Blivis, D

    2010-06-01

    Sacrocaudal afferent (SCA) stimulation is used in this work to study neural pathways involved in sensory-activation of central pattern generators (CPGs) in the isolated spinal cord of the neonatal rat. Surgical manipulations of the white matter funiculi and confocal imaging of back-labeled funicular pathways suggest that the CPGs are activated during SCA stimulation by crossed and uncrossed multifunicular projections of sacral neurons and that activation of short projecting proprioneurons is sufficient for the generation of the rhythm by SCA stimulation. The versatile organization of the pathways involved in the SCA-induced rhythm makes it a potent and durable activator of the CPGs in the absence of descending control from the brain. The significance of our findings and their potential clinical use are discussed.

  5. Dominance and interloci interactions in transcriptional activation cascades: models explaining compensatory mutations and inheritance patterns.

    PubMed

    Bost, Bruno; Veitia, Reiner A

    2014-01-01

    Mutations in human genes encoding transcription factors are often dominant because one active allele cannot ensure a normal phenotype (haploinsufficiency). In other instances, heterozygous mutations of two genes are required for a phenotype to appear (combined haploinsufficiency). Here, we explore with models (i) the basis of haploinsufficiency and combined haploinsufficiency owing to mutations in transcription activators, and (ii) how the effects of such mutations can be amplified or buffered by subsequent steps in a transcription cascade. We propose that the non-linear (sigmoidal) response of transcription to the concentration of activators can explain haploinsufficiency. We further show that the sigmoidal character of the output of a cascade increases with the number of steps involved, the settings of which will determine the buffering or enhancement of the effects of a decreased concentration of an upstream activator. This exploration provides insights into the bases of compensatory mutations and on interloci interactions underlying oligogenic inheritance patterns.

  6. Angiogenesis Interactome and Time Course Microarray Data Reveal the Distinct Activation Patterns in Endothelial Cells

    PubMed Central

    Chu, Liang-Hui; Lee, Esak; Bader, Joel S.; Popel, Aleksander S.

    2014-01-01

    Angiogenesis involves stimulation of endothelial cells (EC) by various cytokines and growth factors, but the signaling mechanisms are not completely understood. Combining dynamic gene expression time-course data for stimulated EC with protein-protein interactions associated with angiogenesis (the “angiome”) could reveal how different stimuli result in different patterns of network activation and could implicate signaling intermediates as points for control or intervention. We constructed the protein-protein interaction networks of positive and negative regulation of angiogenesis comprising 367 and 245 proteins, respectively. We used five published gene expression datasets derived from in vitro assays using different types of blood endothelial cells stimulated by VEGFA (vascular endothelial growth factor A). We used the Short Time-series Expression Miner (STEM) to identify significant temporal gene expression profiles. The statistically significant patterns between 2D fibronectin and 3D type I collagen substrates for telomerase-immortalized EC (TIME) show that different substrates could influence the temporal gene activation patterns in the same cell line. We investigated the different activation patterns among 18 transmembrane tyrosine kinase receptors, and experimentally measured the protein level of the tyrosine-kinase receptors VEGFR1, VEGFR2 and VEGFR3 in human umbilical vein EC (HUVEC) and human microvascular EC (MEC). The results show that VEGFR1–VEGFR2 levels are more closely coupled than VEGFR1–VEGFR3 or VEGFR2–VEGFR3 in HUVEC and MEC. This computational methodology can be extended to investigate other molecules or biological processes such as cell cycle. PMID:25329517

  7. Spatial Co-Occurrence and Activity Patterns of Mesocarnivores in the Temperate Forests of Southwest China

    PubMed Central

    Bu, Hongliang; Wang, Fang; McShea, William J.; Lu, Zhi; Wang, Dajun; Li, Sheng

    2016-01-01

    Understanding the interactions between species and their coexistence mechanisms will help explain biodiversity maintenance and enable managers to make sound conservation decisions. Mesocarnivores are abundant and diverse mid-sized carnivores and can have profound impacts on the function, structure and dynamics of ecosystem after the extirpation of apex predators in many ecosystems. The moist temperate forests of Southwest China harbor a diverse community of mesocarnivores in the absence of apex predators. Sympatric species tend to partition limited resources along time, diet and space to facilitate coexistence. We determined the spatial and temporal patterns for five species of mesocarnivores. We used detection histories from a large camera-trap dataset collected from 2004–2015 with an extensive effort of 23,313 camera-days from 495 camera locations. The five mesocarnivore species included masked palm civet Paguma larvata, leopard cat Prionailurus bengalensis, hog badger Arctonyx collaris, yellow-throated marten Martes flavigula, and Siberian weasel Mustela sibirica. Only the masked palm civet and hog badger tended to avoid each other; while for other pairs of species, they occurred independently of each other, or no clear pattern observed. With regard to seasonal activity, yellow-throated marten was most active in winter, opposite the pattern observed for masked palm civet, leopard cat and hog badger. For diel activity, masked palm civet, leopard cat and hog badger were primarily nocturnal and crepuscular; yellow-throated marten was diurnal, and Siberian weasel had no clear pattern for most of the year (March to November), but was nocturnal in the winter (December to February). The seasonal shift of the Siberian weasel may be due to the high diet overlap among species in winter. Our results provided new facts and insights into this unique community of mesocarnivores of southwest China, and will facilitate future studies on the mechanism determining coexistence

  8. Different dynamic resting state fMRI patterns are linked to different frequencies of neural activity.

    PubMed

    Thompson, Garth John; Pan, Wen-Ju; Keilholz, Shella Dawn

    2015-07-01

    Resting state functional magnetic resonance imaging (rsfMRI) results have indicated that network mapping can contribute to understanding behavior and disease, but it has been difficult to translate the maps created with rsfMRI to neuroelectrical states in the brain. Recently, dynamic analyses have revealed multiple patterns in the rsfMRI signal that are strongly associated with particular bands of neural activity. To further investigate these findings, simultaneously recorded invasive electrophysiology and rsfMRI from rats were used to examine two types of electrical activity (directly measured low-frequency/infraslow activity and band-limited power of higher frequencies) and two types of dynamic rsfMRI (quasi-periodic patterns or QPP, and sliding window correlation or SWC). The relationship between neural activity and dynamic rsfMRI was tested under three anesthetic states in rats: dexmedetomidine and high and low doses of isoflurane. Under dexmedetomidine, the lightest anesthetic, infraslow electrophysiology correlated with QPP but not SWC, whereas band-limited power in higher frequencies correlated with SWC but not QPP. Results were similar under isoflurane; however, the QPP was also correlated to band-limited power, possibly due to the burst-suppression state induced by the anesthetic agent. The results provide additional support for the hypothesis that the two types of dynamic rsfMRI are linked to different frequencies of neural activity, but isoflurane anesthesia may make this relationship more complicated. Understanding which neural frequency bands appear as particular dynamic patterns in rsfMRI may ultimately help isolate components of the rsfMRI signal that are of interest to disorders such as schizophrenia and attention deficit disorder.

  9. Different dynamic resting state fMRI patterns are linked to different frequencies of neural activity

    PubMed Central

    Thompson, Garth John; Pan, Wen-Ju

    2015-01-01

    Resting state functional magnetic resonance imaging (rsfMRI) results have indicated that network mapping can contribute to understanding behavior and disease, but it has been difficult to translate the maps created with rsfMRI to neuroelectrical states in the brain. Recently, dynamic analyses have revealed multiple patterns in the rsfMRI signal that are strongly associated with particular bands of neural activity. To further investigate these findings, simultaneously recorded invasive electrophysiology and rsfMRI from rats were used to examine two types of electrical activity (directly measured low-frequency/infraslow activity and band-limited power of higher frequencies) and two types of dynamic rsfMRI (quasi-periodic patterns or QPP, and sliding window correlation or SWC). The relationship between neural activity and dynamic rsfMRI was tested under three anesthetic states in rats: dexmedetomidine and high and low doses of isoflurane. Under dexmedetomidine, the lightest anesthetic, infraslow electrophysiology correlated with QPP but not SWC, whereas band-limited power in higher frequencies correlated with SWC but not QPP. Results were similar under isoflurane; however, the QPP was also correlated to band-limited power, possibly due to the burst-suppression state induced by the anesthetic agent. The results provide additional support for the hypothesis that the two types of dynamic rsfMRI are linked to different frequencies of neural activity, but isoflurane anesthesia may make this relationship more complicated. Understanding which neural frequency bands appear as particular dynamic patterns in rsfMRI may ultimately help isolate components of the rsfMRI signal that are of interest to disorders such as schizophrenia and attention deficit disorder. PMID:26041826

  10. Moderate Peep After Tracheal Lipopolysaccharide Instillation Prevents Inflammation and Modifies the Pattern of Brain Neuronal Activation

    PubMed Central

    Quilez, María Elisa; Rodríguez-González, Raquel; Turon, Marc; Fernandez-Gonzalo, Sol; Villar, Jesús; Kacmarek, Robert M.; Gómez, Ma Nieves; Oliva, Joan Carles; Blanch, Lluís; López-Aguilar, Josefina

    2015-01-01

    ABSTRACT Background: Ventilatory strategy and specifically positive end-expiratory pressure (PEEP) can modulate the inflammatory response and pulmonary-to-systemic translocation of lipopolysaccharide (LPS). Both inflammation and ventilatory pattern may modify brain activation, possibly worsening the patient's outcome and resulting in cognitive sequelae. Methods: We prospectively studied Sprague–Dawley rats randomly assigned to undergo 3 h mechanical ventilation with 7 mL/kg tidal ventilation and either 2 cmH2O or 7 cmH2O PEEP after intratracheal instillation of LPS or saline. Healthy nonventilated rats served as baseline. We analyzed lung mechanics, gas exchange, lung and plasma cytokine levels, lung apoptotic cells, and lung neutrophil infiltration. To evaluate brain neuronal activation, we counted c-Fos immunopositive cells in the retrosplenial cortex (RS), thalamus, supraoptic nucleus (SON), nucleus of the solitary tract (NTS), paraventricular nucleus (PVN), and central amygdala (CeA). Results: LPS increased lung neutrophilic infiltration, lung and systemic MCP-1 levels, and neuronal activation in the CeA and NTS. LPS-instilled rats receiving 7 cmH2O PEEP had less lung and systemic inflammation and more c-Fos-immunopositive cells in the RS, SON, and thalamus than those receiving 2 cmH2O PEEP. Applying 7 cmH2O PEEP increased neuronal activation in the CeA and NTS in saline-instilled rats, but not in LPS-instilled rats. Conclusions: Moderate PEEP prevented lung and systemic inflammation secondary to intratracheal LPS instillation. PEEP also modified the neuronal activation pattern in the RS, SON, and thalamus. The relevance of these differential brain c-Fos expression patterns in neurocognitive outcomes should be explored. PMID:26398809

  11. Urinary Lactate Dehydrogenase Activity and Its Isozyme Patterns in Kawasaki Disease

    PubMed Central

    Kawamura, Yoichi; Kanai, Takashi; Takizawa, Mari; Yoshida, Yusuke; Tsujita, Yuki; Nonoyama, Shigeaki

    2017-01-01

    Abnormal urinary findings, such as sterile pyuria, proteinuria, and microscopic hematuria, are often seen in the acute phase of Kawasaki disease (KD). We investigated the potential significance of urinary lactate dehydrogenase (U-LDH) activity and its isozyme patterns in KD. Total U-LDH activity and its isozymes (U-LDH1-5) levels were compared among 120 patients with KD, 18 patients with viral infection (VI), and 43 patients with upper urinary tract infection (UTI) and additionally compared between intravenous immunoglobulin (IVIG) responders (n = 89) and nonresponders (n = 31) with KD. Total U-LDH activity was higher in KD (35.4 ± 4.8 IU/L, P < 0.05) and UTI patients (66.0 ± 8.0 IU/L, P < 0.01) than in VI patients (17.0 ± 6.2 IU/L). In the isozyme pattern analysis, KD patients had high levels of U-LDH1 and U-LDH2, while UTI patients had high levels of U-LDH3, U-LDH4, and U-LDH5. Furthermore, IVIG nonresponders of KD had significantly higher levels of total U-LDH activity (45.1 ± 4.7 IU/L, P < 0.05), especially U-LDH1 and U-LDH2 (P < 0.05), than IVIG responders (32.0 ± 2.8 IU/L). KD patients have increased levels of total U-LDH activity, especially U-LDH-1 and U-LDH2, indicating a unique pattern of U-LDH isozymes different from that in UTI patients. PMID:28348604

  12. Automated swimming activity monitor for examining temporal patterns of toxicant effects on individual Daphnia magna.

    PubMed

    Bahrndorff, Simon; Michaelsen, Thomas Yssing; Jensen, Anne; Marcussen, Laurits Faarup; Nielsen, Majken Elley; Roslev, Peter

    2016-07-01

    Aquatic pollutants are often biologically active at low concentrations and impact on biota in combination with other abiotic stressors. Traditional toxicity tests may not detect these effects, and there is a need for sensitive high-throughput methods for detecting sublethal effects. We have evaluated an automated infra-red (IR) light-based monitor for recording the swimming activity of Daphnia magna to establish temporal patterns of toxicant effects on an individual level. Activity was recorded for 48 h and the sensitivity of the monitor was evaluated by exposing D. magna to the reference chemicals K2 Cr2 O7 at 15, 20 and 25 °C and 2,4-dichlorophenol at 20 °C. Significant effects (P < 0.001) of toxicant concentrations, exposure time and incubation temperatures were observed. At 15 °C, the swimming activity remained unchanged for 48 h at sublethal concentrations of K2 Cr2 O7 whereas activity at 20 and 25 °C was more biphasic with decreases in activity occurring after 12-18 h. A similar biphasic pattern was observed after 2,4-dichlorophenol exposure at 20 °C. EC50 values for 2,4-dichlorophenol and K2 Cr2 O7 determined from automated recording of swimming activity showed increasing toxicity with time corresponding to decreases in EC50 of 0.03-0.07 mg l(-1) h(-1) . EC50 values determined after 48 h were comparable or lower than EC50 values based on visual inspection according to ISO 6341. The results demonstrated that the swimming activity monitor is capable of detecting sublethal behavioural effects that are toxicant and temperature dependent. The method allows EC values to be established at different time points and can serve as a high-throughput screening tool in toxicity testing. Copyright © 2015 John Wiley & Sons, Ltd.

  13. Affordances for Risk-Taking and Physical Activity in Australian Early Childhood Education Settings

    ERIC Educational Resources Information Center

    Little, Helen; Sweller, Naomi

    2015-01-01

    Motor competence and physical activity (PA) patterns are established during the early childhood years. Early childhood education (ECE) settings are an important context for children's engagement in physically active play. This paper reports the findings from an online survey examining resources, spaces and affordances for PA and risk-taking in…

  14. Ambient noise and temporal patterns of boat activity in the US Virgin Islands National Park.

    PubMed

    Kaplan, Maxwell B; Mooney, T Aran

    2015-09-15

    Human activity is contributing increasing noise to marine ecosystems. Recent studies have examined the effects of boat noise on marine fishes, but there is limited understanding of the prevalence of this type of sound source. This investigation tracks vessel noise on three reefs in the US Virgin Islands National Park over four months in 2013. Ambient noise levels ranged from 106 to 129dBrms re 1μPa (100Hz-20kHz). Boat noise occurred in 6-12% of samples. In the presence of boat noise, ambient noise in a low-frequency band (100-1000Hz) increased by >7dB above baseline levels and sound levels were significantly higher. The frequency with the most acoustic energy shifted to a significantly lower frequency when boat noise was present during the day. These results indicate the abundance of boat noise and its overlap with reef organism sound production, raising concern for the communication abilities of these animals.

  15. Reconstruction of human brain spontaneous activity based on frequency-pattern analysis of magnetoencephalography data

    PubMed Central

    Llinás, Rodolfo R.; Ustinin, Mikhail N.; Rykunov, Stanislav D.; Boyko, Anna I.; Sychev, Vyacheslav V.; Walton, Kerry D.; Rabello, Guilherme M.; Garcia, John

    2015-01-01

    A new method for the analysis and localization of brain activity has been developed, based on multichannel magnetic field recordings, over minutes, superimposed on the MRI of the individual. Here, a high resolution Fourier Transform is obtained over the entire recording period, leading to a detailed multi-frequency spectrum. Further analysis implements a total decomposition of the frequency components into functionally invariant entities, each having an invariant field pattern localizable in recording space. The method, addressed as functional tomography, makes it possible to find the distribution of magnetic field sources in space. Here, the method is applied to the analysis of simulated data, to oscillating signals activating a physical current dipoles phantom, and to recordings of spontaneous brain activity in 10 healthy adults. In the analysis of simulated data, 61 dipoles are localized with 0.7 mm precision. Concerning the physical phantom the method is able to localize three simultaneously activated current dipoles with 1 mm precision. Spatial resolution 3 mm was attained when localizing spontaneous alpha rhythm activity in 10 healthy adults, where the alpha peak was specified for each subject individually. Co-registration of the functional tomograms with each subject's head MRI localized alpha range activity to the occipital and/or posterior parietal brain region. This is the first application of this new functional tomography to human brain activity. The method successfully provides an overall view of brain electrical activity, a detailed spectral description and, combined with MRI, the localization of sources in anatomical brain space. PMID:26528119

  16. Gender differences in physical activity patterns among older adults who fall☆

    PubMed Central

    Stahl, Sarah T.; Albert, Steven M.

    2016-01-01

    Objective This study describes gender differences in the level and pattern of physical activity in groups of older adults who were frequent fallers, intermittent fallers, or non-fallers. Methods Interviews were conducted with adults aged 50 years and older (N = 1834) at senior centers across Pennsylvania from 2010 to 2011. Self-reported falls and validated measures of physical activity were collected at baseline and at 6- and 12-month follow-up assessments. Results Complete follow-up data were available for 1487 participants. Men who fell frequently decreased in recreational/leisure activity and household/yard work compared to the intermittent fallers and non-fallers. This association remained even when controlling for baseline health status. All women—regardless of fall group—engaged in similar levels of recreational/leisure activity and household/yard work over time. For both men and women, frequent fallers also showed a greater decrease in walking activities compared to intermittent fallers and non-fallers. Discussion Frequent falling among older adults is associated with declines in common leisure, household, and walking activities. The effect of falling frequency on physical activity appears to affect men and women differently, generating the hypothesis that interventions to promote physical activity among fallers need to be gender specific. PMID:25535677

  17. Seasonal and Daily Activity Patterns of Mosquito (Diptera: Culicidae) Vectors of Pathogens in Northeastern Italy.

    PubMed

    Montarsi, Fabrizio; Mazzon, Luca; Cazzin, Stefania; Ciocchetta, Silvia; Capelli, Gioia

    2015-01-01

    The seasonal and daily activity of mosquito vectors of pathogens affecting animals and humans were studied in northeastern Italy at a site within the Po River Delta Park. A CDC-CO2 trap and a gravid trap were operated at 2-h intervals for 24 h every 15 d from May to October 2010. Overall, 5,788 mosquitoes comprising six species were collected, namely Culex pipiens L. (75.1% of total), Aedes caspius (Pallas) (15.2%), Aedes vexans (Meigen) (6.9%), Anopheles maculipennis s.l. Meigen (2.6%), Culiseta annulata (Schrank) (0.2%), and Culex modestus Ficalbi (<0.1%). The relative abundance of these species increased from May until the beginning of July and then decreased, disappearing at the beginning of October. The diel host-seeking patterns and oviposition site-seeking patterns were species specific and were differentially affected by the ecological variables recorded at the day and hour of mosquito collection or two weeks before collection. Knowledge of the seasonal and daily host-seeking patterns of mosquitoes highlights the time periods of the day and the seasons of potential exposure for animals and humans to mosquito-borne pathogens, therefore delineating the best time for the application of preventive measures. Furthermore, knowledge of the oviposition site-seeking activity of the mosquitoes optimizes the capture of gravid females, thereby enhancing the likelihood of detecting pathogens.

  18. Quorum activation at a distance: spatiotemporal patterns of gene regulation from diffusion of an autoinducer signal

    NASA Astrophysics Data System (ADS)

    Dilanji, Gabriel; Langebrake, Jessica; Deleenheer, Patrick; Hagen, Stephen J.

    2012-02-01

    Bacteria in colonies coordinate gene regulation through the exchange of diffusible signal molecules known as autoinducers (AI). This ``quorum signaling'' often occurs in physically heterogeneous and spatially extended environments such as biofilms. Under these conditions the space and time scales for diffusion of the signal limit the range and timing of effective gene regulation. We expect that spatial and temporal patterns of gene expression will reflect physical environmental constraints as well as nonlinear transcriptional activation and feedback within the gene regulatory system. We have combined experiments and modeling to investigate how these spatiotemporal patterns develop. We embed engineered plasmid/GFP quorum sensor strains or wild type strains in a long narrow agar lane, and then introduce AI signal at one terminus of the lane. Diffusion of the AI initiates reporter expression along the length of the lane, extending to macroscopic distances of mm-cm. Resulting patterns are captured quantitatively by a mathematical model that incorporates logistic growth of the population, diffusion of AI, and nonlinear transcriptional activation. Our results show that a diffusing quorum signal can coordinate gene expression over distances of order 1cm on time scales of order 10 hrs.

  19. Evolution of muscle activity patterns driving motions of the jaw and hyoid during chewing in Gnathostomes.

    PubMed

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

    2011-08-01

    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.

  20. 75 FR 69468 - Metlife Moosic, PA, Metlife Clarks Summit, PA; Notice of Affirmative Determination Regarding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Metlife Moosic, PA, Metlife Clarks Summit, PA; Notice of Affirmative Determination Regarding Application for Reconsideration By application dated August 2, 2010, the...

  1. Patterns of physical activity determined by heart rate monitoring among diabetic children

    PubMed Central

    Massin, M; Lebrethon, M; Rocour, D; Gerard, P; Bourguignon, J

    2005-01-01

    Background: Children with type 1 diabetes should be encouraged to participate in physical activity because exercise can benefit insulin sensitivity and improve known risk factors for atherosclerosis. Methods: Physical activity patterns of 127 children and adolescents with stable type 1 diabetes were investigated by 24 hour continuous heart rate monitoring. The percentage of heart rate reserve was used to measure the amounts of physical activity at different intensities. The results were compared with normative data. Results: Diabetic preschoolchildren accumulated 192.7 (78.1), 39.1 (24.3), and 21.3 (9.4) minutes/day (mean (SD)) of light, moderate, and vigorous physical activity, respectively. At the same activity levels, diabetic schoolchildren accumulated 168.9 (76.7), 37.9 (15.9), and 19.0 (14.8) minutes/day, and diabetic teenagers accumulated 166.3 (67.5), 45.6 (26.9), and 25.2 (15.3) minutes/day. Diabetic schoolchildren were significantly more active than healthy peers when considering moderate activity; diabetic teenagers were significantly more active when considering moderate and vigorous activity. There was a negative correlation between the most recent glycated haemoglobin and the time spent in light activities in schoolchildren, and a negative correlation between mean glycated haemoglobin for one year and time spent in light and moderate activities in schoolchildren. Conclusion: The majority of our diabetic patients meet the classical paediatric guidelines for physical activity and compare favourably with their healthy peers. PMID:15941770

  2. Impact of time-activity patterns on personal exposure to black carbon

    NASA Astrophysics Data System (ADS)

    Dons, Evi; Int Panis, Luc; Van Poppel, Martine; Theunis, Jan; Willems, Hanny; Torfs, Rudi; Wets, Geert

    2011-07-01

    Time-activity patterns are an important determinant of personal exposure to air pollution. This is demonstrated by measuring personal exposure of 16 participants for 7 consecutive days: 8 couples of which one person was a full-time worker and the other was a homemaker; both had a very different time-activity pattern. We used portable aethalometers to measure black carbon levels with a high temporal resolution and a PDA with GPS-logger and electronic diary. The exposure to black carbon differs between partners by up to 30%, although they live at the same location. The activity contributing most to this difference is transport: Average exposure in transport is 6445 ng m -3, followed by exposure during shopping (2584 ng m -3). Average exposure is lowest while sleeping (1153 ng m -3) and when doing home-based activities (1223 ng m -3). Full-time workers spend almost twice as much time in transport as the homemakers. As a result of the study design we measured in several different homes, shops, cars, etc. enabling a better insight in true overall exposure in those microenvironments. Other factors influencing personal exposure are: background concentrations and location of residence in an urban, suburban or rural environment.

  3. [The influence of proficiency level of foreign language on the activation patterns of language areas].

    PubMed

    Bryll, Amira; Binder, Marek; Urbanik, Andrzej

    2013-01-01

    The of aim of the present study was the estimation of the influence of proficiency level of the second language on activation patterns of language areas. 30 volunteers participated in the experiment (15 females and 15 males) from 18 to 40 years of age. Mean age was 28 years. All participants were divided by linguist into two groups according to their proficiency level of the foreign language: high proficiency group (HP) and low proficiency group (LP). Block design method was used in the performed experiment. The experimental task was speech production in the form of sentences, the control tusk was silence. The experiment was performed using 1,5 T MR system. Functional data analysis was performed using SPM2 software (Wellcome Department of Cognitive Neurology, Great Britain). In low proficiency group (LP) stronger activation was found in right inferior frontal gyrus (pars tiangulris) incuding insula and in the left hemisphere on the border of supramarginal and superior temporal gyrus. In high proficiency group (HP) more activated in second language (L2) was the left inferior frontal gyrus (pars tiangulris), and a small part of left middle frontal gyrus. Proficiency level of the second language influences the pattern of activation of language areas.

  4. 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.

  5. Dopamine receptors set the pattern of activity generated in subthalamic neurons.

    PubMed

    Baufreton, J; Zhu, Z-T; Garret, M; Bioulac, B; Johnson, S W; Taupignon, A I

    2005-11-01

    Information processing in the brain requires adequate background neuronal activity. As Parkinson's disease progresses, patients typically become akinetic; the death of dopaminergic neurons leads to a dopamine-depleted state, which disrupts information processing related to movement in a brain area called the basal ganglia. Using agonists of dopamine receptors in the D1 and D2 families on rat brain slices, we show that dopamine receptors in these two families govern the firing pattern of neurons in the subthalamic nucleus, a crucial part of the basal ganglia. We propose a conceptual frame, based on specific properties of dopamine receptors, to account for the dominance of different background firing patterns in normal and dopamine-depleted states.

  6. 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.

  7. Calcium-activated chloride channels as a new target to control the spiking pattern of neurons.

    PubMed

    Ha, Go Eun; Cheong, Eunji

    2017-03-03

    Neuronal firing patterns and frequencies determine the nature of encoded information in the neural circuits. Here we discuss the molecular identity and cellular mechanisms of spike-frequency adaptation in central nervous system (CNS). Spike-frequency adaptation in thalamocortical (TC) and CA1 hippocampal neurons is mediated by the Ca2+-activated Cl- channel (CACC) anoctamin-2 (ANO2). Knockdown of ANO2 in these neurons results in significantly reduced spike-frequency adaptation along with increased number of spikes. No previous study has described the finding that CACCs mediate afterhyperpolarization currents, which result in the modulation of neuronal spike patterns in the central nervous system. Therefore, our study proposes a novel role for ANO2 in spike-frequency adaptation and transmission of information in the brain.

  8. Longitudinal Patterns of Active Leisure among South African Youth: Gender Differences and Associations with Health Risk Behaviours.

    PubMed

    Tibbits, Melissa K; Caldwell, Linda L; Smith, Edward A; Vergnani, Tania; Wegner, Lisa

    This study identified adolescents' patterns of active leisure participation over two years and five waves of data and how those patterns were related to substance use and sexual activity. Participants included 3581 primarily Colored (mixed race) South African adolescents. Latent class analysis was utilized to determine patterns of active leisure patterns and multinomial logistic regression was used to examine the relationships between the patterns and substance use and sexual activity. Four patterns were identified: Non-Participants; Early Participants; Late Participants; and Consistent Participants. Most males were Consistent Participants, whereas most females were Non-participants. Female Consistent Participants had the lowest odds of tobacco use, marijuana use, and sexual activity by the tenth grade relative to the other patterns, whereas Early Participants had the highest odds. In contrast, male Consistent Participants were at moderate risk of engaging in health risk behaviors relative to the other patterns. These findings suggest the need for a cautious approach to developing active leisure-based interventions, taking into account the contextual factors that may influence participation and health risk behaviors.

  9. Longitudinal Patterns of Active Leisure among South African Youth: Gender Differences and Associations with Health Risk Behaviours

    PubMed Central

    Tibbits, Melissa K.; Caldwell, Linda L.; Smith, Edward A.; Vergnani, Tania; Wegner, Lisa

    2015-01-01

    This study identified adolescents’ patterns of active leisure participation over two years and five waves of data and how those patterns were related to substance use and sexual activity. Participants included 3581 primarily Colored (mixed race) South African adolescents. Latent class analysis was utilized to determine patterns of active leisure patterns and multinomial logistic regression was used to examine the relationships between the patterns and substance use and sexual activity. Four patterns were identified: Non-Participants; Early Participants; Late Participants; and Consistent Participants. Most males were Consistent Participants, whereas most females were Non-participants. Female Consistent Participants had the lowest odds of tobacco use, marijuana use, and sexual activity by the tenth grade relative to the other patterns, whereas Early Participants had the highest odds. In contrast, male Consistent Participants were at moderate risk of engaging in health risk behaviors relative to the other patterns. These findings suggest the need for a cautious approach to developing active leisure-based interventions, taking into account the contextual factors that may influence participation and health risk behaviors. PMID:27019655

  10. Somatostatinergic modulation of firing pattern and calcium-activated potassium currents in medium spiny neostriatal neurons.

    PubMed

    Galarraga, E; Vilchis, C; Tkatch, T; Salgado, H; Tecuapetla, F; Perez-Rosello, T; Perez-Garci, E; Hernandez-Echeagaray, E; Surmeier, D J; Bargas, J

    2007-05-11

    Somatostatin is synthesized and released by aspiny GABAergic interneurons of the neostriatum, some of them identified as low threshold spike generating neurons (LTS-interneurons). These neurons make synaptic contacts with spiny neostriatal projection neurons. However, very few somatostatin actions on projection neurons have been described. The present work reports that somatostatin modulates the Ca(2+) activated K(+) currents (K(Ca) currents) expressed by projection cells. These actions contribute in designing the firing pattern of the spiny projection neuron; which is the output of the neostriatum. Small conductance (SK) and large conductance (BK) K(Ca) currents represent between 30% and 50% of the sustained outward current in spiny cells. Somatostatin reduces SK-type K(+) currents and at the same time enhances BK-type K(+) currents. This dual effect enhances the fast component of the after hyperpolarizing potential while reducing the slow component. Somatostatin then modifies the firing pattern of spiny neurons which changed from a tonic regular pattern to an interrupted "stuttering"-like pattern. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) tissue expression analysis of dorsal striatal somatostatinergic receptors (SSTR) mRNA revealed that all five SSTR mRNAs are present. However, single cell RT-PCR profiling suggests that the most probable receptor in charge of this modulation is the SSTR2 receptor. Interestingly, aspiny interneurons may exhibit a "stuttering"-like firing pattern. Therefore, somatostatin actions appear to be the entrainment of projection neurons to the rhythms generated by some interneurons. Somatostatin is then capable of modifying the processing and output of the neostriatum.

  11. Effect of early adult patterns of physical activity and television viewing on midlife cognitive function

    PubMed Central

    Hoang, Tina D.; Reis, Jared; Zhu, Na; Jacobs, David R.; Launer, Lenore J.; Whitmer, Rachel A.; Sidney, Stephen; Yaffe, Kristine

    2015-01-01

    Importance Sedentary behaviors and physical inactivity are not only increasing worldwide but also are critical risk factors for adverse health outcomes. Yet few studies have examined the effects of sedentary behavior on cognition or the long-term role of either behavior in early-to-middle adulthood. Objective To investigate the association between 25-year patterns of television viewing and physical activity and mid-life cognition. Design, Setting, and Participants Prospective study of 3,247 adults (black and white race, aged 18-30 years) enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study (March 25, 1985 to August 31, 2011). Main Outcome and Measures We assessed television viewing and physical activity at repeated visits (≥3 assessments) over 25 years using a validated questionnaire. A 25-year pattern of high television viewing was defined as watching TV above the upper baseline quartile (>3 hours/day) for more than two-thirds of the visits, and a 25-year pattern of low physical activity was defined as activity levels below the lower, sex-specific baseline quartile for more than two-thirds of the visits. We evaluated cognitive function at Year 25 using the Digit Symbol Substitution Test (DSST), Stroop Test, and Rey Auditory Verbal Learning Test. Results Compared with participants with low television viewing, those with high television viewing during 25 years (323 of 3247 [10.9%]) were more likely to have poor cognitive performance (<1 SD below the race-specific mean) on the DSST and Stroop test, with findings reported as adjusted odds ratio (95% CI): DSST, 1.64 (1.21-2.23); Stroop, 1.56 (1.13-2.14) but not the Rey Auditory Verbal Learning Test adjusted for age, race, sex, educational level, smoking, alcohol, body mass index, and hypertension. Low physical activity during 25 years in 528 of 3247 participants (16.3%) was significantly associated with poor performance on the DSST, (1.47 1.14-1.90). Compared with participants with low

  12. 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

  13. Tractography Activation Patterns in Dorsolateral Prefrontal Cortex Suggest Better Clinical Responses in OCD DBS

    PubMed Central

    Hartmann, Christian J.; Lujan, J. Luis; Chaturvedi, Ashutosh; Goodman, Wayne K.; Okun, Michael S.; McIntyre, Cameron C.; Haq, Ihtsham U.

    2016-01-01

    Background: Medication resistant obsessive-compulsive disorder (OCD) patients can be successfully treated with Deep Brain Stimulation (DBS) which targets the anterior limb of the internal capsule (ALIC) and the nucleus accumbens (NA). Growing evidence suggests that in patients who respond to DBS, axonal fiber bundles surrounding the electrode are activated, but it is currently unknown which discrete pathways are critical for optimal benefit. Our aim was to identify axonal pathways mediating clinical effects of ALIC-NA DBS. Methods: We created computational models of ALIC-NA DBS to simulate the activation of fiber tracts and to identify connected cerebral regions. The pattern of activated axons and their cortical targets was investigated in six OCD patients who underwent ALIC-NA DBS. Results: Modulation of the right anterior middle frontal gyrus (dorsolateral prefrontal cortex) was associated with an excellent response. In contrast, non-responders showed high activation in the orbital part of the right inferior frontal gyrus (lateral orbitofrontal cortex/anterior ventrolateral prefrontal cortex). Factor analysis followed by step-wise linear regression indicated that YBOCS improvement was inversely associated with factors that were predominantly determined by gray matter activation results. Discussion: Our findings support the hypothesis that optimal therapeutic results are associated with the activation of distinct fiber pathways. This suggests that in DBS for OCD, focused stimulation of specific fiber pathways, which would allow for stimulation with lower amplitudes, may be superior to activation of a wide array of pathways, typically associated with higher stimulation amplitudes. PMID:26834544

  14. Analysis of muscle activation patterns during transitions into and out of high knee flexion postures.

    PubMed

    Tennant, Liana M; Maly, Monica R; Callaghan, Jack P; Acker, Stacey M

    2014-10-01

    Increased risk of medial tibiofemoral osteoarthritis (OA) is linked to occupations that require frequent transitions into and out of postures which require high knee flexion (>90°). Muscle forces are major contributors to joint loading, and an association between compressive forces due to muscle activations and the degeneration of joint cartilage has been suggested. The purpose of this study was to evaluate muscle activation patterns of muscles crossing the knee during transitions into and out of full-flexion kneeling and squatting, sitting in a low chair, and gait. Both net and co-activation were greater when transitioning out of high flexion postures, with maximum activation occurring at knee angles greater than 100°. Compared to gait, co-activation levels during high flexion transitions were up to approximately 3 times greater. Co-activation was significantly greater in the lateral muscle group compared to the medial group during transitions into and out of high flexion postures. These results suggest that compression due to activation of the medial musculature of the knee may not be the link between high knee flexion postures and increased medial knee OA observed in occupational settings. Further research on a larger subject group and workers with varying degrees of knee OA is necessary.

  15. Relation between abnormal patterns of muscle activation and response to common peroneal nerve stimulation in hemiplegia

    PubMed Central

    Burridge, J; McLellan, D

    2000-01-01

    OBJECTIVE—To investigate the relation between response to common peroneal nerve stimulation, timed to the swing phase of walking, and abnormal ankle movement and muscle activation patterns.
METHOD—Eighteen patients who took part had a drop foot and had had a stroke at least 6 months before the study Twelve age matched normal subjects were also studied. Response to stimulation was measured by changes in the speed and effort of walking when the stimulator was used. Speed was measured over 10 m and effort by the physiological cost index. Abnormal ankle movement and muscle activation were measured in a rig by ability to follow a tracking signal moving sinusoidally at either 1 or 2 Hz, resistance to passive movement, and EMG activity during both passive and active movements. Indices were derived to define EMG response to passive stretch, coactivation, and ability to activate muscles appropriately during active movement
RESULTS—Different mechanisms underlying the drop foot were seen. Results showed that patients who had poor control of ankle movement and spasticity, demonstrated by stretch reflex and coactivation, were more likely to respond well to stimulation. Those with mechanical resistance to passive movement and with normal muscle activation responded less well.
CONCLUSIONS—The results support the hypothesis that stimulation of the common peroneal nerve to elicit a contraction of the anterior tibial muscles also inhibits the antagonist calf muscles. The technique used may be useful in directing physiotherapy by indicating the underlying cause of the drop foot.

 PMID:10945810

  16. Heavy-duty truck population, activity and usage patterns. Final report

    SciTech Connect

    Fischer, M.

    1998-07-01

    The objective of the study was to update the heavy-duty truck (HDT) population, activity (e.g., vehicle miles traveled (VMT), numbers of starts and trips, trip duration, etc.), and usage patterns type of service/business (e.g., delivery, construction, etc.), area of operation (i.e., local, short-haul, long-haul) for HDT`s registered and/or operated in California. The population and activity estimates were done on a weight-class-specific basis light-heavy-duty, medium-heavy-duty and heavy-heavy-duty. Population, activity and usage estimates were based primarily on Department of Motor Vehicles (DMV) registration data and Truck Inventory and Usage Survey (TIUS) data. In addition to the analysis of existing data (i.e., DMV and TIUS), 42 HDTs were fitted with on-board data loggers that recorded numbers of trips and starts, daily VMT and travel by time-of-day.

  17. 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.

  18. Development of a method of exposed characteristic points in activity pattern for rat behaviour classification

    NASA Astrophysics Data System (ADS)

    Stefko, Kamil; Bukowski, Tomasz; Urbański, Michał

    2012-03-01

    A fast method for visual inspection and classification of massive locomotor activity data registered from laboratory rats is presented. Positions in the home cage of one hundred rats have been constantly recorded during 90 day period using photodiodes and beam crossing method with use of custom build system. Direct inspection and comparison of classic form of actograms did not bring information for fast and easy recognition of anomalies in daily behavioural cycle. A method of obtaining fast and easy to compare locomotor activity pattern is presented. The key point of proposed method is exposition of characteristic points in the activity diagram. About 9000 actograms were inspected and classified for investigation with use of ANOVA.

  19. Reticular activating system of a central pattern generator: premovement electrical potentials.

    PubMed

    Tapia, Jesus A; Trejo, Argelia; Linares, Pablo; Alva, J Manuel; Kristeva, Rumyana; Manjarrez, Elias

    2013-10-01

    For the first time, here we characterize a bulbar reticular activating system (RAS) of neurons in decerebrate, deafferented and decerebellated cats producing a premovement electrical potential that we named obex slow potential (OSP). The OSP occurs about 0.8 ± 0.4 sec prior to the onset of a fictive-scratching-episode. Here, we describe two classes of bulbar neurons, off-on, which are silent but exhibit a 80 ± 56 Hz firing discharge at the beginning of (and during) the OSP, and on-off interneurons, with a 27 ± 14 Hz firing activity that stops at the beginning of (and during) the OSP. We suggest that these OSP-associated neurons belong to a descending RAS, which contributes to the activation of the spinal central pattern generators.

  20. [Psychophysiologic pattern of pilot's activity during flight as a basis for setting up his workplace].

    PubMed

    Frolov, N I

    1997-01-01

    The psychophysiological pattern of a pilot is considered on the basis of experiments made during flights. Five components of his activity, which may be estimated, are identified. These include sensory, motor, autonomic, occupational, and psychological components. The "reserves of attention" are singled out as an objective independent parameter that characterizes the activity of a pilot. Five determinants of the level of physiological responses are identified in a pilot during flight. Their mechanisms are most efficiently analyzed in terms of the basic concepts developed by P.K. Anokhin, P.V. Simonov, K.V. Sudakov. The objective activity estimates make it possible to assess the adequacy of a working place to the problems to be solved, to apply the anthrocentric principle in working out the pilot's working place by taking into account his psychophysiological capacities.

  1. Estimating muscle activation patterns using a surrogate model of facial biomechanics.

    PubMed

    Wu, Tim; Martens, Harald; Hunter, Peter; Mithraratne, Kumar

    2013-01-01

    Analyzing the muscle activities that drive the expressive facial gestures can be a useful tool in assessing one's emotional state of mind. Since the skin motion is much easier to measure in comparison to the actual electrical excitation signal of facial muscles, a biomechanical model of the human face driven by these muscles can be a useful tool in relating the geometric information to the muscle activity. However, long computational time often hinders its practicality. The objective of this study was to replace the precise but computationally demanding biomechanical model by a much faster multivariate meta-model (surrogate model), such that a significant speedup (real-time interactive speed) can be achieved and data from the biomechanical model can be practically exploited. Using the proposed surrogate, muscle activation patterns of six key facial expressions were estimated in the iterative fit from the structured-light scanned geometric information.

  2. The predatory behavior of wintering Accipiter hawks: temporal patterns in activity of predators and prey.

    PubMed

    Roth, Timothy C; Lima, Steven L

    2007-05-01

    Studies focused on how prey trade-off predation and starvation risk are prevalent in behavioral ecology. However, our current understanding of these trade-offs is limited in one key respect: we know little about the behavior of predators. In this study, we provide some of the first detailed information on temporal patterns in the daily hunting behavior of bird-eating Accipiter hawks and relate that to their prey. During the winters of 1999-2004, twenty-one sharp-shinned hawks (A. striatus) and ten Cooper's hawks (A. cooperii) were intensively radio tracked in rural and urban habitats in western Indiana, USA. Cooper's hawks left roost before sunrise and usually returned to roost around sunset, while sharp-shinned hawks left roost at sunrise or later and returned to roost well before sunset. An overall measure of Cooper's-hawk-induced risk (a composite variable of attack rate and activity patterns) generally reflected the timing of prey activity, with peaks occurring around sunrise and sunset. In contrast, risk induced by the smaller sharp-shinned hawk did not strongly reflect the activity of their prey. Specifically, an early morning peak in prey activity did not correspond to a period with intense hawk activity. The lack of early morning hunting by sharp-shinned hawks may reflect the high risk of owl-induced predation experienced by these hawks. The net effect of this intraguild predation may be to "free" small birds from much hawk-induced predation risk prior to sunrise. This realization presents an alternative to energetics as an explanation for the early morning peak in small bird activity during the winter.

  3. Influence of sleep timing behavior on weight status and activity patterns in adults with intellectual disabilities.

    PubMed

    Mikulovic, Jacques; Dieu, Olivier; Fardy, Paul S; Bui-Xuan, Gilles; Vanhelst, Jérémy

    2014-12-01

    The aim was to explore the relationship between sleep habits and overweight/obesity, physical activity and sedentary behaviors in French adults with intellectual disabilities. This observational study was conducted on 570 French adults with intellectual deficiency. Sleep habits were analyzed and related to anthropometric measures, physical activity and sedentary behaviors. The study was conducted using a self-administered questionnaire. Participants completed the questionnaire during an interview with the principal investigator. Sleep timing behavior was classified into 4 sleep patterns: Early-bed/Early-rise, Early-bed/Late-rise, Late-bed/Late-rise, and Late-bed/Early-rise. Of 570 eligible participants, 61 were excluded because of missing data on age, weight or height. The number of