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Sample records for detecting dyrk activity

  1. Selectivity Profiling and Biological Activity of Novel β-Carbolines as Potent and Selective DYRK1 Kinase Inhibitors.

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    Katharina Rüben

    Full Text Available DYRK1A is a pleiotropic protein kinase with diverse functions in cellular regulation, including cell cycle control, neuronal differentiation, and synaptic transmission. Enhanced activity and overexpression of DYRK1A have been linked to altered brain development and function in Down syndrome and neurodegenerative diseases such as Alzheimer's disease. The β-carboline alkaloid harmine is a high affinity inhibitor of DYRK1A but suffers from the drawback of inhibiting monoamine oxidase A (MAO-A with even higher potency. Here we characterized a series of novel harmine analogs with minimal or absent MAO-A inhibitory activity. We identified several inhibitors with submicromolar potencies for DYRK1A and selectivity for DYRK1A and DYRK1B over the related kinases DYRK2 and HIPK2. An optimized inhibitor, AnnH75, inhibited CLK1, CLK4, and haspin/GSG2 as the only off-targets in a panel of 300 protein kinases. In cellular assays, AnnH75 dose-dependently reduced the phosphorylation of three known DYRK1A substrates (SF3B1, SEPT4, and tau without negative effects on cell viability. AnnH75 inhibited the cotranslational tyrosine autophosphorylation of DYRK1A and threonine phosphorylation of an exogenous substrate protein with similar potency. In conclusion, we have characterized an optimized β-carboline inhibitor as a highly selective chemical probe that complies with desirable properties of drug-like molecules and is suitable to interrogate the function of DYRK1A in biological studies.

  2. Structures of down syndrome kinases, DYRKs, reveal mechanisms of kinase activation and substrate recognition

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    Soundararajan, M.; Roos, A.K.; Savitsky, P.

    2013-01-01

    Dual-specificity tyrosine-(Y)-phosphorylation-regulated kinases (DYRKs) play key roles in brain development, regulation of splicing, and apoptosis, and are potential drug targets for neurodegenerative diseases and cancer. We present crystal structures of one representative member of each DYRK sub...

  3. Inhibitors of dual-specificity tyrosine phosphorylation-regulated kinases (DYRK) exert a strong anti-herpesviral activity.

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    Hutterer, Corina; Milbradt, Jens; Hamilton, Stuart; Zaja, Mirko; Leban, Johann; Henry, Christophe; Vitt, Daniel; Steingruber, Mirjam; Sonntag, Eric; Zeitträger, Isabel; Bahsi, Hanife; Stamminger, Thomas; Rawlinson, William; Strobl, Stefan; Marschall, Manfred

    2017-07-01

    Infection with human cytomegalovirus (HCMV) is a serious medical problem, particularly in immunocompromised individuals and neonates. The success of (val)ganciclovir therapy is hampered by low drug compatibility and induction of viral resistance. A novel strategy of antiviral treatment is based on the exploitation of cell-directed signaling, e. g. pathways with a known relevance for carcinogenesis and tumor drug development. Here we describe a principle for putative antiviral drugs based on targeting dual-specificity tyrosine phosphorylation-regulated kinases (DYRKs). DYRKs constitute an evolutionarily conserved family of protein kinases with key roles in the control of cell proliferation and differentiation. Members of the DYRK family are capable of phosphorylating a number of substrate proteins, including regulators of the cell cycle, e.g. DYRK1B can induce cell cycle arrest, a critical step for the regulation of HCMV replication. Here we provide first evidence for a critical role of DYRKs during viral replication and the high antiviral potential of DYRK inhibitors (SC84227, SC97202 and SC97208, Harmine and AZ-191). Using established replication assays for laboratory and clinically relevant strains of HCMV, concentration-dependent profiles of inhibition were obtained. Mean inhibitory concentrations (EC50) of 0.98 ± 0.08 μM/SC84227, 0.60 ± 0.02 μM/SC97202, 6.26 ± 1.64 μM/SC97208, 0.71 ± 0.019 μM/Harmine and 0.63 ± 0.23 μM/AZ-191 were determined with HCMV strain AD169-GFP for the infection of primary human fibroblasts. A first analysis of the mode of antiviral action suggested a block of viral replication at the early-late stage of HCMV gene expression. Moreover, rhesus macaque cytomegalovirus (RhCMV), varicella-zoster virus (VZV) and herpes simplex virus (HSV-1) showed a similarly high sensitivity to these compounds. Thus, we conclude that DYRK signaling represents a promising target pathway for the development of novel anti

  4. DYRK1A Controls HIV-1 Replication at a Transcriptional Level in an NFAT Dependent Manner.

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    Thijs Booiman

    Full Text Available Transcription of the HIV-1 provirus is regulated by both viral and host proteins and is very important in the context of viral latency. In latently infected cells, viral gene expression is inhibited as a result of the sequestration of host transcription factors and epigenetic modifications.In our present study we analyzed the effect of host factor dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A on HIV-1 replication. We show that DYRK1A controls HIV-1 replication by regulating provirus transcription. Downregulation or inhibition of DYRK1A increased LTR-driven transcription and viral replication in cell lines and primary PBMC. Furthermore, inhibition of DYRK1A resulted in reactivation of latent HIV-1 provirus to a similar extent as two commonly used broad-spectrum HDAC inhibitors. We observed that DYRK1A regulates HIV-1 transcription via the Nuclear Factor of Activated T-cells (NFAT by promoting its translocation from the nucleus to the cytoplasm. Therefore, inhibition of DYRK1A results in increased nuclear levels of NFAT and increased NFAT binding to the viral LTR and thus increasing viral transcription.Our data indicate that host factor DYRK1A plays a role in the regulation of viral transcription and latency. Therefore, DYRK1A might be an attractive candidate for therapeutic strategies targeting the viral reservoir.

  5. Overexpression of DYRK1A, a Down Syndrome Candidate gene, Impairs Primordial Germ Cells Maintenance and Migration in zebrafish.

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    Liu, Yanyan; Lin, Ziyuan; Liu, Mingfeng; Wang, He; Sun, Huaqin

    2017-11-10

    DYRK1A, located on chromosome 21, is a major candidate gene of Down syndrome (DS, trisomy21), and its overexpression is associated with abnormal phenotype of Down syndrome patients. The defects of gonads and germ cells in Down Syndrome suggest that overexpression of DYRK1A has potential effect on primordial germ cells (PGCs) development. Human and zebrafish DYRK1A protein sequence possess 75.6% similarity and same function domains, suggesting the evolutional conservation. Here, we used zebrafish model to detect the definite role of excessive expression of DYRK1A in PGCs development during embryogenesis. We injected DYRK1A mRNA into embryos and detected the PGCs marker gene vasa and nanos1. Results showed depletion in numbers and disordering migration of PGCs in human or zebrafish DYRK1A overexpressed zebrafish embryos. Quantitative proteome analysis indicated that embryonic proteins were significantly altered in DYRK1A overexpressed embryos. Of note, ca15b and piwil1, two identified critical factors for PGCs development, showed ectopic expression induced by overexpressed DYRK1A. In brief, we demonstrate that overexpression of DYRK1A, a candidate gene of Down's syndrome, impairs PGCs development during early embryogenesis by altering key factors in embryos. Importantly, our work may provide a conceivable mechanism for the gonads and germ cells defects of Down syndrome patients.

  6. Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) inhibitors: a survey of recent patent literature.

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    Nguyen, Thu Lan; Fruit, Corinne; Hérault, Yann; Meijer, Laurent; Besson, Thierry

    2017-11-01

    Dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) is a eukaryotic serine-threonine protein kinase belonging to the CMGC group. DYRK1A hyperactivity appears to contribute to the development of a number of human malignancies and to cognitive deficits observed in Down syndrome and Alzheimer's disease. As a result, the DYRK1A kinase represents an attractive target for the synthesis and optimization of pharmacological inhibitors of potential therapeutic interest. Like most tyrosine kinase inhibitors developed up to the market, DYRK1A inhibitors are essentially acting by competing with ATP for binding at the catalytic site of the kinase. Areas covered: This paper reviews patent activity associated with the discovery of synthetic novel heterocyclic molecules inhibiting the catalytic activity of DYRK1A. Expert opinion: Despite the important role of DYRK1A in biological processes and the growing interest in the design of new therapeutic drugs, there are only few patented synthetic DYRK1A inhibitors and most of them were and are still developed by academic research groups, sometimes with industrial partners.

  7. Library-based discovery of DYRK1A/CLK1 inhibitors from natural product extracts.

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    Grabher, Patrick; Durieu, Emilie; Kouloura, Eirini; Halabalaki, Maria; Skaltsounis, Leandros A; Meijer, Laurent; Hamburger, Matthias; Potterat, Olivier

    2012-06-01

    The dual specificity tyrosine-phosphorylation-regulated kinase DYRK1A possesses diverse roles in neuronal development and adult brain physiology, and increased activity has been linked to neurodegenerative diseases. Very few inhibitors of this kinase have been reported up to now. Screening of a library of > 900 plant and fungal extracts afforded 25 extracts with IC₅₀s Larrea tridentata as the active constituents. Active extracts and compounds were also tested on the closely related cdc2-like kinase CLK1. Finally, the selectivity profile of compounds was evaluated by including other members of the DYRKs and CLKs families. While the flavonoids and emodin did not show significant differences in the potency of their activities, harmine (1) was most active against DYRK1A, CLK1, and CLK4, and less potent against the other kinases, with selectivity ranging from 2- to 20-fold. Georg Thieme Verlag KG Stuttgart · New York.

  8. Characterization of the human DYRK1A promoter and its regulation by the transcription factor E2F1

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    Galceran Juan

    2008-03-01

    Full Text Available Abstract Background Overexpression of the human DYRK1A gene due to the presence of a third gene copy in trisomy 21 is thought to play a role in the pathogenesis of Down syndrome. The observation of gene dosage effects in transgenic mouse models implies that subtle changes in expression levels can affect the correct function of the DYRK1A gene product. We have therefore characterized the promoter of the human DYRK1A gene in order to study its transcriptional regulation. Results Transcription start sites of the human DYRK1A gene are distributed over 800 bp within a region previously identified as an unmethylated CpG island. We have identified a new alternative noncoding 5'-exon of the DYRK1A gene which is located 772 bp upstream of the previously described transcription start site. Transcription of the two splicing variants is controlled by non-overlapping promoter regions that can independently drive reporter gene expression. We found no evidence of cell- or tissue-specific promoter usage, but the two promoter regions differed in their activity and their regulation. The sequence upstream of exon 1A (promoter region A induced about 10-fold higher reporter gene activity than the sequence upstream of exon 1B (promoter region B. Overexpression of the transcription factor E2F1 increased DYRK1A mRNA levels in Saos2 and Phoenix cells and enhanced the activity of promoter region B three- to fourfold. Conclusion The identification of two alternatively spliced transcripts whose transcription is initiated from differentially regulated promoters regions indicates that the expression of the DYRK1A gene is subject to complex control mechanisms. The regulatory effect of E2F1 suggests that DYRK1A may play a role in cell cycle regulation or apoptosis.

  9. Natural aristolactams and aporphine alkaloids as inhibitors of CDK1/cyclin B and DYRK1A.

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    Marti, Guillaume; Eparvier, Véronique; Morleo, Barbara; Le Ven, Jessica; Apel, Cécile; Bodo, Bernard; Amand, Séverine; Dumontet, Vincent; Lozach, Olivier; Meijer, Laurent; Guéritte, Françoise; Litaudon, Marc

    2013-03-06

    In an effort to find potent inhibitors of the protein kinases DYRK1A and CDK1/Cyclin B, a systematic in vitro evaluation of 2,500 plant extracts from New Caledonia and French Guyana was performed. Some extracts were found to strongly inhibit the activity of these kinases. Four aristolactams and one lignan were purified from the ethyl acetate extracts of Oxandra asbeckii and Goniothalamus dumontetii, and eleven aporphine alkaloids were isolated from the alkaloid extracts of Siparuna pachyantha, S. decipiens, S. guianensis and S. poeppigii. Among these compounds, velutinam, aristolactam AIIIA and medioresinol showed submicromolar IC50 values on DYRK1A.

  10. Natural Aristolactams and Aporphine Alkaloids as Inhibitors of CDK1/Cyclin B and DYRK1A

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    Françoise Guéritte

    2013-03-01

    Full Text Available In an effort to find potent inhibitors of the protein kinases DYRK1A and CDK1/Cyclin B, a systematic in vitro evaluation of 2,500 plant extracts from New Caledonia and French Guyana was performed. Some extracts were found to strongly inhibit the activity of these kinases. Four aristolactams and one lignan were purified from the ethyl acetate extracts of Oxandra asbeckii and Goniothalamus dumontetii, and eleven aporphine alkaloids were isolated from the alkaloid extracts of Siparuna pachyantha, S. decipiens, S. guianensis and S. poeppigii. Among these compounds, velutinam, aristolactam AIIIA and medioresinol showed submicromolar IC50 values on DYRK1A.

  11. Corrective effects of hepatotoxicity by hepatic Dyrk1a gene delivery in mice with intermediate hyperhomocysteinemia

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    Alizée Latour

    2015-03-01

    Full Text Available Hyperhomocysteinemia results from hepatic metabolism dysfunction and is characterized by a high plasma homocysteine level, which is also an independent risk factor for cardiovascular disease. Elevated levels of homocysteine in plasma lead to hepatic lesions and abnormal lipid metabolism. Therefore, lowering homocysteine levels might offer therapeutic benefits. Recently, we were able to lower plasma homocysteine levels in mice with moderate hyperhomocysteinemia using an adenoviral construct designed to restrict the expression of DYRK1A, a serine/threonine kinase involved in methionine metabolism (and therefore homocysteine production, to hepatocytes. Here, we aimed to extend our previous findings by analyzing the effect of hepatocyte-specific Dyrk1a gene transfer on intermediate hyperhomocysteinemia and its associated hepatic toxicity and liver dysfunction. Commensurate with decreased plasma homocysteine and alanine aminotransferase levels, targeted hepatic expression of DYRK1A in mice with intermediate hyperhomocysteinemia resulted in elevated plasma paraoxonase-1 and lecithin:cholesterol acyltransferase activities and apolipoprotein A–I levels. It also rescued hepatic apolipoprotein E, J, and D levels. Further, Akt/GSK3/cyclin D1 signaling pathways in the liver of treated mice were altered, which may help prevent homocysteine-induced cell cycle dysfunction. DYRK1A gene therapy could be useful in the treatment of hyperhomocysteinemia in populations, such as end-stage renal disease patients, who are unresponsive to B-complex vitamin therapy.

  12. Overexpression of Dyrk1A, a Down Syndrome Candidate, Decreases Excitability and Impairs Gamma Oscillations in the Prefrontal Cortex.

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    Ruiz-Mejias, Marcel; Martinez de Lagran, Maria; Mattia, Maurizio; Castano-Prat, Patricia; Perez-Mendez, Lorena; Ciria-Suarez, Laura; Gener, Thomas; Sancristobal, Belen; García-Ojalvo, Jordi; Gruart, Agnès; Delgado-García, José M; Sanchez-Vives, Maria V; Dierssen, Mara

    2016-03-30

    The dual-specificity tyrosine phosphorylation-regulated kinase DYRK1A is a serine/threonine kinase involved in neuronal differentiation and synaptic plasticity and a major candidate of Down syndrome brain alterations and cognitive deficits. DYRK1A is strongly expressed in the cerebral cortex, and its overexpression leads to defective cortical pyramidal cell morphology, synaptic plasticity deficits, and altered excitation/inhibition balance. These previous observations, however, do not allow predicting how the behavior of the prefrontal cortex (PFC) network and the resulting properties of its emergent activity are affected. Here, we integrate functional, anatomical, and computational data describing the prefrontal network alterations in transgenic mice overexpressingDyrk1A(TgDyrk1A). Usingin vivoextracellular recordings, we show decreased firing rate and gamma frequency power in the prefrontal network of anesthetized and awakeTgDyrk1Amice. Immunohistochemical analysis identified a selective reduction of vesicular GABA transporter punctae on parvalbumin positive neurons, without changes in the number of cortical GABAergic neurons in the PFC ofTgDyrk1Amice, which suggests that selective disinhibition of parvalbumin interneurons would result in an overinhibited functional network. Using a conductance-based computational model, we quantitatively demonstrate that this alteration could explain the observed functional deficits including decreased gamma power and firing rate. Our results suggest that dysfunction of cortical fast-spiking interneurons might be central to the pathophysiology of Down syndrome. DYRK1Ais a major candidate gene in Down syndrome. Its overexpression results into altered cognitive abilities, explained by defective cortical microarchitecture and excitation/inhibition imbalance. An open question is how these deficits impact the functionality of the prefrontal cortex network. Combining functional, anatomical, and computational approaches, we identified

  13. Minibrain/Dyrk1a regulates food intake through the Sir2-FOXO-sNPF/NPY pathway in Drosophila and mammals.

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    Seung-Hyun Hong

    Full Text Available Feeding behavior is one of the most essential activities in animals, which is tightly regulated by neuroendocrine factors. Drosophila melanogaster short neuropeptide F (sNPF and the mammalian functional homolog neuropeptide Y (NPY regulate food intake. Understanding the molecular mechanism of sNPF and NPY signaling is critical to elucidate feeding regulation. Here, we found that minibrain (mnb and the mammalian ortholog Dyrk1a, target genes of sNPF and NPY signaling, [corrected] regulate food intake in Drosophila melanogaster and mice. In Drosophila melanogaster neuronal cells and mouse hypothalamic cells, sNPF and NPY modulated the mnb and Dyrk1a expression through the PKA-CREB pathway. Increased Dyrk1a activated Sirt1 to regulate the deacetylation of FOXO, which potentiated FOXO-induced sNPF/NPY expression and in turn promoted food intake. Conversely, AKT-mediated insulin signaling suppressed FOXO-mediated sNPF/NPY expression, which resulted in decreasing food intake. Furthermore, human Dyrk1a transgenic mice exhibited decreased FOXO acetylation and increased NPY expression in the hypothalamus, and [corrected] increased food intake. Our findings demonstrate that Mnb/Dyrk1a regulates food intake through the evolutionary conserved Sir2-FOXO-sNPF/NPY pathway in Drosophila melanogaster and mammals.

  14. Truncation of the Down syndrome candidate gene DYRK1A in two unrelated patients with microcephaly

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    Møller, Rikke S; Kübart, Sabine; Hoeltzenbein, Maria

    2008-01-01

    .2. DYRK1A belongs to the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) family, which is highly conserved throughout evolution. Given its localization in both the Down syndrome critical region and in the minimal region for partial monosomy 21, the gene has been studied intensively...... in animals and in humans, and DYRK1A has been proposed to be involved in the neurodevelopmental alterations associated with these syndromes. In the present study, we show that truncating mutations of DYRK1A result in a clinical phenotype including microcephaly....

  15. Green tea polyphenols rescue of brain defects induced by overexpression of DYRK1A.

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    Fayçal Guedj

    Full Text Available Individuals with partial HSA21 trisomies and mice with partial MMU16 trisomies containing an extra copy of the DYRK1A gene present various alterations in brain morphogenesis. They present also learning impairments modeling those encountered in Down syndrome. Previous MRI and histological analyses of a transgenic mice generated using a human YAC construct that contains five genes including DYRK1A reveal that DYRK1A is involved, during development, in the control of brain volume and cell density of specific brain regions. Gene dosage correction induces a rescue of the brain volume alterations. DYRK1A is also involved in the control of synaptic plasticity and memory consolidation. Increased gene dosage results in brain morphogenesis defects, low BDNF levels and mnemonic deficits in these mice. Epigallocatechin gallate (EGCG - a member of a natural polyphenols family, found in great amount in green tea leaves - is a specific and safe DYRK1A inhibitor. We maintained control and transgenic mice overexpressing DYRK1A on two different polyphenol-based diets, from gestation to adulthood. The major features of the transgenic phenotype were rescued in these mice.

  16. A wake-up call to quiescent cancer cells - potential use of DYRK1B inhibitors in cancer therapy.

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    Becker, Walter

    2017-11-28

    Nondividing cancer cells are relatively resistant to chemotherapeutic drugs and environmental stress factors. Promoting cell cycle re-entry of quiescent cancer cells is a potential strategy to enhance the cytotoxicity of agents that target cycling cells. It is therefore important to elucidate the mechanisms by which these cells are maintained in the quiescent state. The protein kinase dual specificity tyrosine phosphorylation-regulated kinase 1B (DYRK1B) is overexpressed in a subset of cancers and maintains cellular quiescence by counteracting G 0 /G 1 -S phase transition. Specifically, DYRK1B controls the S phase checkpoint by stabilizing the cyclin-dependent kinase (CDK) inhibitor p27 Kip1 and inducing the degradation of cyclin D. DYRK1B also stabilizes the DREAM complex that represses cell cycle gene expression in G 0 arrested cells. In addition, DYRK1B enhances cell survival by upregulating antioxidant gene expression and reducing intracellular levels of reactive oxygen species (ROS). Substantial evidence indicates that depletion or inhibition of DYRK1B drives cell cycle re-entry and enhances apoptosis of those quiescent cancer cells with high expression of DYRK1B. Furthermore, small molecule DYRK1B inhibitors sensitize cells to the cytotoxic effects of anticancer drugs that target proliferating cells. These encouraging findings justify continued efforts to investigate the use of DYRK1B inhibitors to disrupt the quiescent state and overturn chemoresistance of noncycling cancer cells. © 2017 Federation of European Biochemical Societies.

  17. Activation analysis. Detection limits

    International Nuclear Information System (INIS)

    Revel, G.

    1999-01-01

    Numerical data and limits of detection related to the four irradiation modes, often used in activation analysis (reactor neutrons, 14 MeV neutrons, photon gamma and charged particles) are presented here. The technical presentation of the activation analysis is detailed in the paper P 2565 of Techniques de l'Ingenieur. (A.L.B.)

  18. Roles of the DYRK kinase Pom2 in cytokinesis, mitochondrial morphology, and sporulation in fission yeast.

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    Pengcheng Wu

    Full Text Available Pom2 is predicted to be a dual-specificity tyrosine-phosphorylation regulated kinase (DYRK related to Pom1 in Schizosaccharomyces pombe. DYRKs share a kinase domain capable of catalyzing autophosphorylation on tyrosine and exogenous phosphorylation on serine/threonine residues. Here we show that Pom2 is functionally different from the well-characterized Pom1, although they share 55% identity in the kinase domain and the Pom2 kinase domain functionally complements that of Pom1. Pom2 localizes to mitochondria throughout the cell cycle and to the contractile ring during late stages of cytokinesis. Overexpression but not deletion of pom2 results in severe defects in cytokinesis, indicating that Pom2 might share an overlapping function with other proteins in regulating cytokinesis. Gain and loss of function analyses reveal that Pom2 is required for maintaining mitochondrial morphology independently of microtubules. Intriguingly, most meiotic pom2Δ cells form aberrant asci with meiotic and/or forespore membrane formation defects. Taken together, Pom2 is a novel DYRK kinase involved in regulating cytokinesis, mitochondrial morphology, meiosis, and sporulation in fission yeast.

  19. DYRK1A (Dual-Specificity Tyrosine-Phosphorylated and -Regulated Kinase 1A: A Gene with Dosage Effect During Development and Neurogenesis

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    M. Dierssen

    2006-01-01

    Full Text Available DYRKs (dual-specificity tyrosine-regulated kinases are an emerging family of evolutionarily conserved dual-specificity kinases that play key roles in cell proliferation, survival, and development. The research in the last years suggests a relevant conserved function during neuronal development, related to proliferation and/or differentiation for DYRK1A. It is expressed in neural progenitor cells and has been proposed to participate in the signaling mechanisms that regulate dendrite differentiation. In Drosophila, disruption of the homolog minibrain gene results in flies with reduced neuroblast proliferation, decreased numbers of central brain neurons, and learning/memory deficits. Knockout DYRK1A mice are embryonic lethal, and heterozygotes show decreased viability and region-specific reductions in brain size. In humans, DYRK1A has been proposed to be involved in the neurodevelopmental alterations associated with Down syndrome. The large number of protein interaction and putative substrates described for DYRK1A suggest multiple pathways and functions to be involved in its developmental function. This review focuses on the functional role that DYRK1A plays in brain development.

  20. Marine-Derived 2-Aminoimidazolone Alkaloids. Leucettamine B-Related Polyandrocarpamines Inhibit Mammalian and Protozoan DYRK & CLK Kinases

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    Nadège Loaëc

    2017-10-01

    Full Text Available A large diversity of 2-aminoimidazolone alkaloids is produced by various marine invertebrates, especially by the marine Calcareous sponges Leucetta and Clathrina. The phylogeny of these sponges and the wide scope of 2-aminoimidazolone alkaloids they produce are reviewed in this article. The origin (invertebrate cells, associated microorganisms, or filtered plankton, physiological functions, and natural molecular targets of these alkaloids are largely unknown. Following the identification of leucettamine B as an inhibitor of selected protein kinases, we synthesized a family of analogues, collectively named leucettines, as potent inhibitors of DYRKs (dual-specificity, tyrosine phosphorylation regulated kinases and CLKs (cdc2-like kinases and potential pharmacological leads for the treatment of several diseases, including Alzheimer’s disease and Down syndrome. We assembled a small library of marine sponge- and ascidian-derived 2-aminoimidazolone alkaloids, along with several synthetic analogues, and tested them on a panel of mammalian and protozoan kinases. Polyandrocarpamines A and B were found to be potent and selective inhibitors of DYRKs and CLKs. They inhibited cyclin D1 phosphorylation on a DYRK1A phosphosite in cultured cells. 2-Aminoimidazolones thus represent a promising chemical scaffold for the design of potential therapeutic drug candidates acting as specific inhibitors of disease-relevant kinases, and possibly other disease-relevant targets.

  1. Overexpression of Dyrk1A is implicated in several cognitive, electrophysiological and neuromorphological alterations found in a mouse model of Down syndrome.

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    Susana García-Cerro

    Full Text Available Down syndrome (DS phenotypes result from the overexpression of several dosage-sensitive genes. The DYRK1A (dual-specificity tyrosine-(Y-phosphorylation regulated kinase 1A gene, which has been implicated in the behavioral and neuronal alterations that are characteristic of DS, plays a role in neuronal progenitor proliferation, neuronal differentiation and long-term potentiation (LTP mechanisms that contribute to the cognitive deficits found in DS. The purpose of this study was to evaluate the effect of Dyrk1A overexpression on the behavioral and cognitive alterations in the Ts65Dn (TS mouse model, which is the most commonly utilized mouse model of DS, as well as on several neuromorphological and electrophysiological properties proposed to underlie these deficits. In this study, we analyzed the phenotypic differences in the progeny obtained from crosses of TS females and heterozygous Dyrk1A (+/- male mice. Our results revealed that normalization of the Dyrk1A copy number in TS mice improved working and reference memory based on the Morris water maze and contextual conditioning based on the fear conditioning test and rescued hippocampal LTP. Concomitant with these functional improvements, normalization of the Dyrk1A expression level in TS mice restored the proliferation and differentiation of hippocampal cells in the adult dentate gyrus (DG and the density of GABAergic and glutamatergic synapse markers in the molecular layer of the hippocampus. However, normalization of the Dyrk1A gene dosage did not affect other structural (e.g., the density of mature hippocampal granule cells, the DG volume and the subgranular zone area or behavioral (i.e., hyperactivity/attention alterations found in the TS mouse. These results suggest that Dyrk1A overexpression is involved in some of the cognitive, electrophysiological and neuromorphological alterations, but not in the structural alterations found in DS, and suggest that pharmacological strategies targeting

  2. Impaired spatial learning strategies and novel object recognition in mice haploinsufficient for the dual specificity tyrosine-regulated kinase-1A (Dyrk1A.

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    Glòria Arqué

    Full Text Available BACKGROUND: Pathogenic aneuploidies involve the concept of dosage-sensitive genes leading to over- and underexpression phenotypes. Monosomy 21 in human leads to mental retardation and skeletal, immune and respiratory function disturbances. Most of the human condition corresponds to partial monosomies suggesting that critical haploinsufficient genes may be responsible for the phenotypes. The DYRK1A gene is localized on the human chromosome 21q22.2 region, and has been proposed to participate in monosomy 21 phenotypes. It encodes a dual-specificity kinase involved in neuronal development and in adult brain physiology, but its possible role as critical haploinsufficient gene in cognitive function has not been explored. METHODOLOGY/PRINCIPAL FINDINGS: We used mice heterozygous for a Dyrk1A targeted mutation (Dyrk1A+/- to investigate the implication of this gene in the cognitive phenotypes of monosomy 21. Performance of Dyrk1A+/- mice was assayed 1/ in a navigational task using the standard hippocampally related version of the Morris water maze, 2/ in a swimming test designed to reveal potential kinesthetic and stress-related behavioral differences between control and heterozygous mice under two levels of aversiveness (25 degrees C and 17 degrees C and 3/ in a long-term novel object recognition task, sensitive to hippocampal damage. Dyrk1A+/- mice showed impairment in the development of spatial learning strategies in a hippocampally-dependent memory task, they were impaired in their novel object recognition ability and were more sensitive to aversive conditions in the swimming test than euploid control animals. CONCLUSIONS/SIGNIFICANCE: The present results are clear examples where removal of a single gene has a profound effect on phenotype and indicate that haploinsufficiency of DYRK1A might contribute to an impairment of cognitive functions and stress coping behavior in human monosomy 21.

  3. DYRK1A-mediated Cyclin D1 Degradation in Neural Stem Cells Contributes to the Neurogenic Cortical Defects in Down Syndrome

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    Sònia Najas

    2015-02-01

    Full Text Available Alterations in cerebral cortex connectivity lead to intellectual disability and in Down syndrome, this is associated with a deficit in cortical neurons that arises during prenatal development. However, the pathogenic mechanisms that cause this deficit have not yet been defined. Here we show that the human DYRK1A kinase on chromosome 21 tightly regulates the nuclear levels of Cyclin D1 in embryonic cortical stem (radial glia cells, and that a modest increase in DYRK1A protein in transgenic embryos lengthens the G1 phase in these progenitors. These alterations promote asymmetric proliferative divisions at the expense of neurogenic divisions, producing a deficit in cortical projection neurons that persists in postnatal stages. Moreover, radial glial progenitors in the Ts65Dn mouse model of Down syndrome have less Cyclin D1, and Dyrk1a is the triplicated gene that causes both early cortical neurogenic defects and decreased nuclear Cyclin D1 levels in this model. These data provide insights into the mechanisms that couple cell cycle regulation and neuron production in cortical neural stem cells, emphasizing that the deleterious effect of DYRK1A triplication in the formation of the cerebral cortex begins at the onset of neurogenesis, which is relevant to the search for early therapeutic interventions in Down syndrome.

  4. IMPROVING CAUSE DETECTION SYSTEMS WITH ACTIVE LEARNING

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    National Aeronautics and Space Administration — IMPROVING CAUSE DETECTION SYSTEMS WITH ACTIVE LEARNING ISAAC PERSING AND VINCENT NG Abstract. Active learning has been successfully applied to many natural language...

  5. On-Chip Detection of Cellular Activity

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    Almog, R.; Daniel, R.; Vernick, S.; Ron, A.; Ben-Yoav, H.; Shacham-Diamand, Y.

    The use of on-chip cellular activity monitoring for biological/chemical sensing is promising for environmental, medical and pharmaceutical applications. The miniaturization revolution in microelectronics is harnessed to provide on-chip detection of cellular activity, opening new horizons for miniature, fast, low cost and portable screening and monitoring devices. In this chapter we survey different on-chip cellular activity detection technologies based on electrochemical, bio-impedance and optical detection. Both prokaryotic and eukaryotic cell-on-chip technologies are mentioned and reviewed.

  6. Voice activity detection for speaker verification systems

    Science.gov (United States)

    Borowski, Filip

    2008-01-01

    Complex algorithm for speech activity detection was presented in this article. It is based on speech enhancement, features extraction and final detection algorithm. The first one was published in ETSI standard as a module of "Advanced front-end feature extraction algorithm" in distributed speech recognition system. It consists of two main parts, noise estimatiom and Wiener filtering. For the final detection modified linear prediction coefficients and spectral entropy features are extracted form denoised signal.

  7. Dual-specificity tyrosine-phosphorylated and regulated kinase 1A (DYRK1A) interacts with the phytanoyl-CoA alpha-hydroxylase associated protein 1 (PAHX-AP1), a brain specific protein.

    Science.gov (United States)

    Bescond, Marilyne; Rahmani, Zohra

    2005-04-01

    Down syndrome (DS) is the most common genetic defect correlated with mental retardation and delayed development. The specific genes responsible for these phenotypic alterations have not yet been defined. Dyrk1A (dual-specificity tyrosine-phosphorylated and regulated kinase 1A), the human ortholog of the Drosophila minibrain gene (mnb), maps to the Down syndrome critical region of human chromosome 21 and is overexpressed in Down syndrome fetal brain. In Drosophila, minibrain is involved in postembryonic neurogenesis. In human, DYRK1A encodes a serine-threonine kinase but despite its potential involvement in the neurobiological alterations associated with Down syndrome, its physiological function has not yet been defined. To gain some insight into its biological function, we used the yeast two-hybrid approach to identify binding partners of DYRK1A. We found that the C-terminal region of DYRK1A interacts with a brain specific protein, phytanoyl-CoA alpha-hydroxylase-associated protein 1 (PAHX-AP1, also named PHYHIP) which was previously shown to interact with phytanoyl-CoA alpha-hydroxylase (PAHX, also named PHYH), a Refsum disease gene product. This interaction was confirmed by co-immunoprecipitation of PC12 cells co-transfected with DYRK1A and PAHX-AP1. Furthermore, immunofluorescence analysis of PC12 cells co-transfected with both plasmids showed a re-distribution of DYRK1A from the nucleus to the cytoplasm where it co-localized with PAHX-AP1. Finally, in PC12 cells co-transfected with both plasmids, DYRK1A was no longer able to interact with the nuclear transcription factor CREB, thereby confirming that the intracellular localization of DYRK1A was changed from the nucleus to the cytoplasm in the presence of PAHX-AP1. Therefore, these data indicate that by inducing a re-localization of DYRK1A into the cytoplasm, PAHX-AP1 may contribute to new cellular functions of DYRK1A and suggest that PAHX-AP1 may be involved in the development of neurological abnormalities

  8. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    Detection of extracellular enzymatic activity in microorganisms isolated from waste vegetable oil contaminated soil using plate methodologies. Eugenia G. Ortiz Lechuga, Isela Quintero Zapata, Katiushka Arévalo Niño ...

  9. Detecting active comets with SDSS

    Energy Technology Data Exchange (ETDEWEB)

    Solontoi, Michael; Ivezic, Zeljko; /Washington U., Seattle, Astron. Dept.; West, Andrew A.; /MIT, MKI; Claire, Mark; /Washington U., Seattle, Astron. Dept.; Juric, Mario; /Princeton U. Observ.; Becker, Andrew; Jones, Lynne; /Washington U., Seattle, Astron. Dept.; Hall, Patrick B.; /York U., Canada; Kent, Steve; /Fermilab; Lupton, Robert H.; /Princeton U. Observ.; Quinn, Tom; /Washington U., Seattle, Astron. Dept. /Princeton U. Observ.

    2010-12-01

    Using a sample of serendipitously discovered active comets in the Sloan Digital Sky Survey (SDSS), we develop well-controlled selection criteria for greatly increasing the efficiency of comet identification in the SDSS catalogs. After follow-up visual inspection of images to reject remaining false positives, the total sample of SDSS comets presented here contains 19 objects, roughly one comet per 10 million other SDSS objects. The good understanding of selection effects allows a study of the population statistics, and we estimate the apparent magnitude distribution to r {approx} 18, the ecliptic latitude distribution, and the comet distribution in SDSS color space. The most surprising results are the extremely narrow range of colors for comets in our sample (e.g. root-mean-square scatter of only {approx}0.06 mag for the g-r color), and the similarity of comet colors to those of jovian Trojans. We discuss the relevance of our results for upcoming deep multi-epoch optical surveys such as the Dark Energy Survey, Pan-STARRS, and the Large Synoptic Survey Telescope (LSST), and estimate that LSST may produce a sample of about 10,000 comets over its 10-year lifetime.

  10. Active fault detection in MIMO systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2014-01-01

    The focus in this paper is on active fault detection (AFD) for MIMO systems with parametric faults. The problem of design of auxiliary inputs with respect to detection of parametric faults is investigated. An analysis of the design of auxiliary inputs is given based on analytic transfer functions...... from auxiliary input to residual outputs. The analysis is based on a singular value decomposition of these transfer functions Based on this analysis, it is possible to design auxiliary input as well as design of the associated residual vector with respect to every single parametric fault in the system...... such that it is possible to detect these faults....

  11. Abnormal Activity Detection Using Pyroelectric Infrared Sensors

    Directory of Open Access Journals (Sweden)

    Xiaomu Luo

    2016-06-01

    Full Text Available Healthy aging is one of the most important social issues. In this paper, we propose a method for abnormal activity detection without any manual labeling of the training samples. By leveraging the Field of View (FOV modulation, the spatio-temporal characteristic of human activity is encoded into low-dimension data stream generated by the ceiling-mounted Pyroelectric Infrared (PIR sensors. The similarity between normal training samples are measured based on Kullback-Leibler (KL divergence of each pair of them. The natural clustering of normal activities is discovered through a self-tuning spectral clustering algorithm with unsupervised model selection on the eigenvectors of a modified similarity matrix. Hidden Markov Models (HMMs are employed to model each cluster of normal activities and form feature vectors. One-Class Support Vector Machines (OSVMs are used to profile the normal activities and detect abnormal activities. To validate the efficacy of our method, we conducted experiments in real indoor environments. The encouraging results show that our method is able to detect abnormal activities given only the normal training samples, which aims to avoid the laborious and inconsistent data labeling process.

  12. Detection of clandestine activities: a global approach

    International Nuclear Information System (INIS)

    Chiappini, R.

    2013-01-01

    The detection of clandestine activities is mainly a question of global approach, dealing with all the steps of the proliferation process. The detection of clandestine activities could be achieved adopting a four step global approach. First, you have to perfectly know the fuel and weapons cycles. Then, you have to be able to describe all the indicators and signatures of those cycles. Once those indicators are known, you need to detect them through the use of the right sensors that could be either technical sensors but also other 'sensors' like export control, visa control and other tools like bibliometry. When all information is available, there is a need for data mining and data fusion including also all open source information. The paper is followed by the slides of the presentation

  13. Fluorescence quenching based alkaline phosphatase activity detection.

    Science.gov (United States)

    Mei, Yaqi; Hu, Qiong; Zhou, Baojing; Zhang, Yonghui; He, Minhui; Xu, Ting; Li, Feng; Kong, Jinming

    2018-01-01

    Simple and fast detection of alkaline phosphatase (ALP) activity is of great importance for diagnostic and analytical applications. In this work, we report a turn-off approach for the real-time detection of ALP activity on the basis of the charge transfer induced fluorescence quenching of the Cu(BCDS) 2 2- (BCDS = bathocuproine disulfonate) probe. Initially, ALP can enzymatically hydrolyze the substrate ascorbic acid 2-phosphate to release ascorbic acid (AA). Subsequently, the AA-mediated reduction of the Cu(BCDS) 2 2- probe, which displays an intense photoluminescence band at the wavelength of 402nm, leads to the static quenching of fluorescence of the probe as a result of charge transfer. The underlying mechanism of the fluorescence quenching was demonstrated by quantum mechanical calculations. The Cu(BCDS) 2 2- probe features a large Stokes shift (86nm) and is highly immune to photo bleaching. In addition, this approach is free of elaborately designed fluorescent probes and allows the detection of ALP activity in a real-time manner. Under optimal conditions, it provides a fast and sensitive detection of ALP activity within the dynamic range of 0-220mUmL -1 , with a detection limit down to 0.27mUmL -1 . Results demonstrate that it is highly selective, and applicable to the screening of ALP inhibitors in drug discovery. More importantly, it shows a good analytical performance for the direct detection of the endogenous ALP levels of undiluted human serum and even whole blood samples. Therefore, the proposed charge transfer based approach has great potential in diagnostic and analytical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The synchronous active neutron detection assay system

    International Nuclear Information System (INIS)

    Pickrell, M.M.; Kendall, P.K.

    1994-01-01

    We have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit a 14-MeV neutron generator developed by Schlumberger. The technique, termed synchronous active neutron detection (SAND), follows a method used routinely in other branches of physics to detect very small signals in presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed ''lock-in'' amplifiers. We have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. The Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. Results are preliminary but promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly; it also appears resilient to background neutron interference. The interrogating neutrons appear to be non-thermal and penetrating. Work remains to fully explore relevant physics and optimize instrument design

  15. Controller modification applied for active fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob; Poulsen, Niels Kjølstad

    2014-01-01

    This paper is focusing on active fault detection (AFD) for parametric faults in closed-loop systems. This auxiliary input applied for the fault detection will also disturb the external output and consequently reduce the performance of the controller. Therefore, only small auxiliary inputs are used...... the feedback controller with a minor effect on the external output in the fault free case. Further, in the faulty case, the signature of the auxiliary input can be optimized. This is obtained by using a band-pass filter for the YJBK parameter that is only effective in a small frequency range where...

  16. Active Exploration for Robust Object Detection

    OpenAIRE

    Velez, Javier J.; Hemann, Garrett A.; Huang, Albert S.; Posner, Ingmar; Roy, Nicholas

    2011-01-01

    Today, mobile robots are increasingly expected to operate in ever more complex and dynamic environments. In order to carry out many of the higher-level tasks envisioned a semantic understanding of a workspace is pivotal. Here our field has benefited significantly from successes in machine learning and vision: applications in robotics of off-the-shelf object detectors are plentiful. This paper outlines an online, any-time planning framework enabling the active exploration of such detections. O...

  17. Automatic Earthquake Detection by Active Learning

    Science.gov (United States)

    Bergen, K.; Beroza, G. C.

    2017-12-01

    In recent years, advances in machine learning have transformed fields such as image recognition, natural language processing and recommender systems. Many of these performance gains have relied on the availability of large, labeled data sets to train high-accuracy models; labeled data sets are those for which each sample includes a target class label, such as waveforms tagged as either earthquakes or noise. Earthquake seismologists are increasingly leveraging machine learning and data mining techniques to detect and analyze weak earthquake signals in large seismic data sets. One of the challenges in applying machine learning to seismic data sets is the limited labeled data problem; learning algorithms need to be given examples of earthquake waveforms, but the number of known events, taken from earthquake catalogs, may be insufficient to build an accurate detector. Furthermore, earthquake catalogs are known to be incomplete, resulting in training data that may be biased towards larger events and contain inaccurate labels. This challenge is compounded by the class imbalance problem; the events of interest, earthquakes, are infrequent relative to noise in continuous data sets, and many learning algorithms perform poorly on rare classes. In this work, we investigate the use of active learning for automatic earthquake detection. Active learning is a type of semi-supervised machine learning that uses a human-in-the-loop approach to strategically supplement a small initial training set. The learning algorithm incorporates domain expertise through interaction between a human expert and the algorithm, with the algorithm actively posing queries to the user to improve detection performance. We demonstrate the potential of active machine learning to improve earthquake detection performance with limited available training data.

  18. Detection of mutagenic activity in automobile exhaust.

    Science.gov (United States)

    Ohnishi, Y; Kachi, K; Sato, K; Tahara, I; Takeyoshi, H; Tokiwa, H

    1980-03-01

    Using the Ames Salmonella-microsome system, we detected mutagenic activity in the exhaust from two kinds of 4-cycle gasoline engines of unregulated and regulated cars, and from diesel engines, as well as in the particulates from air collected in tunnels. The mutagenicity of particulates from a car equipped with a catalyst (regulated car), as compared with that from an unregulated car, was reduced very much (down to 500 from 4500 revertants/plate/m3 in tester strain TA98). However, the mutagenicity of the ether-soluble acid and neutral fractions from the condensed water of emissions from a regulated car was still high (down to 2880 from 10 900 revertants/plate/m3 in tester strain TA100). The mutagenic activity of emission exhaust from old diesel car engines was very high; the particulates showed 9140 and 19 600 revertants/plate/m3 from strain TA98 incubated with an activating rat-liver S9 fraction. A small diesel engine of the type used for the generation of electric power or in farm machinery also produced exhaust with highly mutagenic particulates. The mutagenic activity of a methanol extract of particulate air pollutants collected in a highway tunnel showed 39 revertants/plate/m3 toward strain TA98 and 87 toward strain TA100. The ether-soluble neutral fraction yielded 86 revertants/plate/m3 from strain TA98 and 100 from strain TA100. This fraction also contained carcinogenic compounds, including benzo[a]pyrene, benzo[e]pyrene, benz[a]anthracene, benzo[ghi]perylene and chrysene. Very high mutagenic activity was detected, especially in the particulate air pollutants collected at night, in another tunnel on a superhighway: 60-88 revertants/plate/m3 from strain TA100 for the sample collected by day, but 121-238, by night. Night traffic includes many more diesel-powered vehicles compared with gasoline-powered automobiles.

  19. Detection of telomerase activity using microchip electrophoresis.

    Science.gov (United States)

    Karasawa, Koji; Arakawa, Hidetoshi

    2015-07-01

    Telomerase participates in malignant transformation or immortalization of cells and thus has attracted attention as an anticancer drug target and diagnostic tumor marker. The telomeric repeat amplification protocol (TRAP) and improved TRAP methods (TRAP-fluorescence, TRAP-hybridization, etc.) are widely used forms of this telomerase assay. However, these approaches generally employ acrylamide gel electrophoresis after amplification of telomeric repeats by polymerase chain reaction (PCR), making these TRAP methods time consuming and technically demanding. In this study we developed a novel telomerase assay using microchip electrophoresis for rapid and highly sensitive detection of telomerase activity in cancer cells. The mixed gel of 0.8% hydroxypropyl methylcellulose (HPMC) and 0.3% polyethylene oxide (PEO) with SYBR Gold (fluorescent reagent) was used for microchip electrophoresis. As a result, the product amplified by a telomerase-positive cell could be measured in one cell per assay and detected with high reproducibility (CV=0.67%) in the short time of 100s. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Voice Activity Detection for Speech Enhancement Applications

    Directory of Open Access Journals (Sweden)

    E. Verteletskaya

    2010-01-01

    Full Text Available This paper describes a study of noise-robust voice activity detection (VAD utilizing the periodicity of the signal, full band signal energy and high band to low band signal energy ratio. Conventional VADs are sensitive to a variably noisy environment especially with low SNR, and also result in cutting off unvoiced regions of speech as well as random oscillating of output VAD decisions. To overcome these problems, the proposed algorithm first identifies voiced regions of speech and then differentiates unvoiced regions from silence or background noise using the energy ratio and total signal energy. The performance of the proposed VAD algorithm is tested on real speech signals. Comparisons confirm that the proposed VAD algorithm outperforms the conventional VAD algorithms, especially in the presence of background noise.

  1. Active mems microbeam device for gas detection

    KAUST Repository

    Bouchaala, Adam M.

    2017-10-05

    Sensors and active switches for applications in gas detection and other fields are described. The devices are based on the softening and hardening nonlinear response behaviors of microelectromechanical systems (MEMS) clamped-clamped microbeams. In that context, embodiments of gas-triggered MEMS microbeam sensors and switches are described. The microbeam devices can be coated with a Metal-Organic Framework to achieve high sensitivity. For gas sensing, an amplitude-based tracking algorithm can be used to quantify an amount of gas captured by the devices according to frequency shift. Noise analysis is also conducted according to the embodiments, which shows that the microbeam devices have high stability against thermal noise. The microbeam devices are also suitable for the generation of binary sensing information for alarming, for example.

  2. Tamper Detection for Active Surveillance Systems

    DEFF Research Database (Denmark)

    Theodore, Tsesmelis; Christensen, Lars; Fihl, Preben

    2013-01-01

    If surveillance data are corrupted they are of no use to neither manually post-investigation nor automatic video analysis. It is therefore critical to automatically be able to detect tampering events such as defocusing, occlusion and displacement. In this work we for the first time ad- dress...

  3. Differential neural activation for camouflage detection task in Field ...

    Indian Academy of Sciences (India)

    2015-11-28

    Nov 28, 2015 ... pertinent to examine the activation patterns in the brain of. FDs as compared to FIs during a search task involving camouflaged objects. We hypothesized that cognitive styles influence camouflage detection, with variance amidst FI and. FD individuals for detection ability, brain activation pattern being the ...

  4. Molecular detection by active Fano-sensor

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Yifei; Guo, Zhongyi [School of Computer and Information, Hefei University of Technology, Hefei, 230009 (China)

    2017-04-15

    The optical properties and sensing performances of the molecular sensors based on plasmonic Fano-resonance (PFR) nanostructures have been numerically investigated in detail. The on-resonance sensor, in which the Fano-resonance position is overlapping with the absorption-band of the detected molecules perfectly, reveals a powerful ability to detect the molecules with a low concentration or thin thickness. By the bias-modulation of a single-layer graphene, the Fano-resonance position of the nanostructures can be tuned effectively. On being modulated properly, the PFR sensor shows an ultrahigh performance because of the unprecedentedly high overlap of the Fano-resonance position with the absorption-band of molecules, which is enabling superior signal strength in the molecular detections based on their vibrational fingerprints. Our proposed strategy may enable the development of dynamic sensors and open exciting prospects for bio-sensing. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Advancing capabilities for detecting undeclared nuclear activities

    International Nuclear Information System (INIS)

    Baute, J.

    2013-01-01

    When a country presents a consistent, transparent and predictable picture of its nuclear programme that is supported by the analysis of all information, IAEA inspectors do not need to go there as frequently for routine verification activities. Rather IAEA can redirect those resources to addressing safeguards issues in the state posing real proliferation concerns. The point is how to establish a coherent picture of a nuclear program and how to identify early warnings of safeguard breaches. A key element is the exploitation of all the information available (open sources, inspection report, satellite imagery, state declarations,...) through effective and quick information analysis. This document is made up of the slides of the presentation

  6. Stochastic Change Detection based on an Active Fault Diagnosis Approach

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad; Niemann, Hans Henrik

    2007-01-01

    The focus in this paper is on stochastic change detection applied in connection with active fault diagnosis (AFD). An auxiliary input signal is applied in AFD. This signal injection in the system will in general allow to obtain a fast change detection/isolation by considering the output or an error...

  7. An Incremental Support Vector Machine based Speech Activity Detection Algorithm.

    Science.gov (United States)

    Xianbo, Xiao; Guangshu, Hu

    2005-01-01

    Traditional voice activity detection algorithms are mostly threshold-based or statistical model-based. All those methods are absent of the ability to react quickly to variations of environments. This paper describes an incremental SVM (Support Vector Machine) method for speech activity detection. The proposed incremental procedure makes it adaptive to variation of environments and the special construction of incremental training data set decreases computing consumption effectively. Experiments results demonstrated its higher end point detection accuracy. Further work will be focused on decreasing computing consumption and importing multi-class SVM classifiers.

  8. Active Detection for Exposing Intelligent Attacks in Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Weerakkody, Sean [Carnegie Mellon Univ., Pittsburgh, PA (United States); Ozel, Omur [Carnegie Mellon Univ., Pittsburgh, PA (United States); Griffioen, Paul [Carnegie Mellon Univ., Pittsburgh, PA (United States); Sinopoli, Bruno [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-07-01

    In this paper, we consider approaches for detecting integrity attacks carried out by intelligent and resourceful adversaries in control systems. Passive detection techniques are often incorporated to identify malicious behavior. Here, the defender utilizes finely-tuned algorithms to process information and make a binary decision, whether the system is healthy or under attack. We demonstrate that passive detection can be ineffective against adversaries with model knowledge and access to a set of input/output channels. We then propose active detection as a tool to detect attacks. In active detection, the defender leverages degrees of freedom he has in the system to detect the adversary. Specifically, the defender will introduce a physical secret kept hidden from the adversary, which can be utilized to authenticate the dynamics. In this regard, we carefully review two approaches for active detection: physical watermarking at the control input, and a moving target approach for generating system dynamics. We examine practical considerations for implementing these technologies and discuss future research directions.

  9. Feasibility of culvert IED detection using thermal neutron activation

    Science.gov (United States)

    Faust, Anthony A.; McFee, John E.; Clifford, Edward T. H.; Andrews, Hugh Robert; Mosquera, Cristian; Roberts, William C.

    2012-06-01

    Bulk explosives hidden in culverts pose a serious threat to the Canadian and allied armies. Culverts provide an opportunity to conceal insurgent activity, avoid the need for detectable surface disturbances, and limit the applicability of conventional sub-surface sensing techniques. Further, in spite of the large masses of explosives that can be employed, the large sensor{target separation makes detection of the bulk explosive content challeng- ing. Defence R&D Canada { Sueld and Bubble Technology Industries have been developing thermal neutron activation (TNA) sensors for detection of buried bulk explosives for over 15 years. The next generation TNA sensor, known as TNA2, incorporates a number of improvements that allow for increased sensor-to-target dis- tances, making it potentially feasible to detect large improvised explosive devices (IEDs) in culverts using TNA. Experiments to determine the ability of TNA2 to detect improvised explosive devices in culverts are described, and the resulting signal levels observed for relevant quantities of explosives are presented. Observations conrm that bulk explosives detection using TNA against a culvert-IED is possible, with large charges posing a detection challenge at least as dicult as that of a deeply buried anti-tank landmine. Because of the prototype nature of the TNA sensor used, it is not yet possible to make denitive statements about the absolute sensitivity or detection time. Further investigation is warranted.

  10. Pulse-driven magnetoimpedance sensor detection of cardiac magnetic activity.

    Directory of Open Access Journals (Sweden)

    Shinsuke Nakayama

    Full Text Available This study sought to establish a convenient method for detecting biomagnetic activity in the heart. Electrical activity of the heart simultaneously induces a magnetic field. Detection of this magnetic activity will enable non-contact, noninvasive evaluation to be made. We improved the sensitivity of a pulse-driven magnetoimpedance (PMI sensor, which is used as an electric compass in mobile phones and as a motion sensor of the operation handle in computer games, toward a pico-Tesla (pT level, and measured magnetic fields on the surface of the thoracic wall in humans. The changes in magnetic field detected by this sensor synchronized with the electric activity of the electrocardiogram (ECG. The shape of the magnetic wave was largely altered by shifting the sensor position within 20 mm in parallel and/or perpendicular to the thoracic wall. The magnetic activity was maximal in the 4th intercostals near the center of the sterna. Furthermore, averaging the magnetic activity at 15 mm in the distance between the thoracic wall and the sensor demonstrated magnetic waves mimicking the P wave and QRS complex. The present study shows the application of PMI sensor in detecting cardiac magnetic activity in several healthy subjects, and suggests future applications of this technology in medicine and biology.

  11. Detection of enzyme activity in decontaminated spices of industrial use

    International Nuclear Information System (INIS)

    Müller, R.; Theobald, R.

    1995-01-01

    A range of decontaminated spices of industrial use have been examinated for their enzymes (catalase, peroxidase, amylase, lipase activity). The genuine enzymes remain fully active in irradiated spices, whereas the microbial load is clearly reduced. In contrast steam treated spices no longer demonstrate enzyme activities. Steam treatment offers e.g. black pepper without lipase activity, which can no longer cause fat deterioration. Low microbial load in combination with clearly detectable enzyme activity in spices is an indication for irradiation, whereas, reduced microbial contamination combined with enzyme inactivation indicate steam treatment of raw material [de

  12. Active acoustic leak detection for LMFBR steam generators. Pt. 7. Potential for small leak detection

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi; Yoshida, Kazuo

    1998-01-01

    In order to prevent the expansion of tube damage and to maintain structural integrity in the steam generators (SGs) of fast breeder reactors (FBR), it is necessary to detect precisely and immediately the leakage of water from heat transfer tubes. Therefore, an active acoustic method, which detects the sound attenuation due to bubbles generated in the sodium-water reactions, is being developed. Previous studies have revealed that the active acoustic method can detect bubbles of 10 l/s (equivalence water leak rate about 10 g/s) within 10 seconds in practical steam generators. In order to prevent the expansion of damage to neighboring tubes, however, it is necessary to detect smaller leakage of water from heat transfer tubes. In this study, in order to evaluate the detection sensitivity of the active method, the signal processing methods for emitter and receiver sound and the detection method for leakage within 1 g/s are investigated experimentally, using an SG full-sector model that simulates the actual SGs. A typical result shows that detection of 0.4 l/s air bubbles (equivalent water leak rate about 0.4 g/s) takes about 80 seconds, which is shorter than the propagation time of damage to neighboring tubes. (author)

  13. Detecting new objects and building models with active robot system

    OpenAIRE

    Stergaršek Kuzmič, Eva

    2010-01-01

    An important element of a cognitive robotic system is the ability to detect novel objects and learn their representations, which are suitable for later recognition and manipulation. The basic assumption of our work is that the detection and segmentation of new objects can be facilitated by an active robotic system, which can not only observe the objects but can also manipulate them. Manipulation supports object segmentation and the accumulation of object features, which provides the basis for...

  14. Detection of cardiac activity changes from human speech

    Science.gov (United States)

    Tovarek, Jaromir; Partila, Pavol; Voznak, Miroslav; Mikulec, Martin; Mehic, Miralem

    2015-05-01

    Impact of changes in blood pressure and pulse from human speech is disclosed in this article. The symptoms of increased physical activity are pulse, systolic and diastolic pressure. There are many methods of measuring and indicating these parameters. The measurements must be carried out using devices which are not used in everyday life. In most cases, the measurement of blood pressure and pulse following health problems or other adverse feelings. Nowadays, research teams are trying to design and implement modern methods in ordinary human activities. The main objective of the proposal is to reduce the delay between detecting the adverse pressure and to the mentioned warning signs and feelings. Common and frequent activity of man is speaking, while it is known that the function of the vocal tract can be affected by the change in heart activity. Therefore, it can be a useful parameter for detecting physiological changes. A method for detecting human physiological changes by speech processing and artificial neural network classification is described in this article. The pulse and blood pressure changes was induced by physical exercises in this experiment. The set of measured subjects was formed by ten healthy volunteers of both sexes. None of the subjects was a professional athlete. The process of the experiment was divided into phases before, during and after physical training. Pulse, systolic, diastolic pressure was measured and voice activity was recorded after each of them. The results of this experiment describe a method for detecting increased cardiac activity from human speech using artificial neural network.

  15. Using Logic Programming to Detect Activities in Pervasive Healthcare

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    2002-01-01

    In this experience paper we present a case study in using logic programming in a pervasive computing project in the healthcare domain. An expert system is used to detect healthcare activities in a pervasive hospital environment where positions of people and things are tracked. Based on detected...... activities an activity-driven computing infrastructure provides computational assistance to healthcare staff on mobile-and pervasive computing equipment. Assistance range from simple activities like fast log-in into the electronic patient medical record system to complex activities like signing for medicine...... given to specific patients. We describe the role of logic programming in the infrastructure and discuss the benefits and problems of using logic programming in a pervasive context....

  16. Detection of person presence and its activity in the bathtub

    International Nuclear Information System (INIS)

    Bujnowski, Adam; Palinski, Arkadiusz; Koscinski, Piotr; Skalski, Lukasz; Skurczynska, Anna; Wtorek, Jerzy

    2013-01-01

    A practical application of a bioimpedance technique for a detection of a bathing person is presented in the paper. It addresses the possibility of supervising people in the bathtub without voiding of their intimacy. The measurement system installed in a fiber-glass or a plastic bathtub is able to detect a presence of the bathing person, to estimate its activity and thus to detect potentially dangerous events. In the paper a principle of measurement, working prototype and measurements are presented. The proposed method can be useful for supporting and supervising bathing of elders, partially disabled or people with some health state risk during the bath and living alone.

  17. Detection of active matriptase using a biotinylated chloromethyl ketone peptide.

    Directory of Open Access Journals (Sweden)

    Sine Godiksen

    Full Text Available Matriptase is a member of the family of type II transmembrane serine proteases that is essential for development and maintenance of several epithelial tissues. Matriptase is synthesized as a single-chain zymogen precursor that is processed into a two-chain disulfide-linked form dependent on its own catalytic activity leading to the hypothesis that matriptase functions at the pinnacle of several protease induced signal cascades. Matriptase is usually found in either its zymogen form or in a complex with its cognate inhibitor hepatocyte growth factor activator inhibitor 1 (HAI-1, whereas the active non-inhibited form has been difficult to detect. In this study, we have developed an assay to detect enzymatically active non-inhibitor-complexed matriptase by using a biotinylated peptide substrate-based chloromethyl ketone (CMK inhibitor. Covalently CMK peptide-bound matriptase is detected by streptavidin pull-down and subsequent analysis by Western blotting. This study presents a novel assay for detection of enzymatically active matriptase in living human and murine cells. The assay can be applied to a variety of cell systems and species.

  18. Novel approaches for single molecule activation and detection

    CERN Document Server

    Benfenati, Fabio; Torre, Vincent

    2014-01-01

    How can we obtain tools able to process and exchange information at the molecular scale In order to do this, it is necessary to activate and detect single molecules under controlled conditions. This book focuses on the generation of biologically-inspired molecular devices. These devices are based on the developments of new photonic tools able to activate and stimulate single molecule machines. Additionally, new light sensitive molecules can be selectively activated by photonic tools. These technological innovations will provide a way to control activation of single light-sensitive molecules, a

  19. Active IR System for Projectile Detection and Tracking

    Directory of Open Access Journals (Sweden)

    STANCIC, I.

    2017-11-01

    Full Text Available Reliable detection and tracking of high-speed projectiles is crucial in providing modern battlefield protection or to be used as a forensic tool. Subsonic projectiles fired from silenced weapons are difficult to detect, whereas reliable tracking of the projectile trajectory is hard to accomplish. Contemporary radar based counter-battery systems showed to be valuable in detection of incoming artillery fire, but are unable to provide detection at close ranges. In this paper, an active IR system is proposed that aims to detect and track incoming projectiles at close ranges. Proposed system is able to reconstruct projectile’s trajectory in space, predict impact location and estimate direction of projectile origin. Active detector system is based on a pair of high-speed cameras in stereo-configuration synced with computer and IR illuminator that emits coded IR light bursts. Innovative IR light coding enables automated detection and tracking of a nearby projectile and elimination of false positive alarms caused by distant objects.

  20. The synchronous active neutron detection system for spent fuel assay

    International Nuclear Information System (INIS)

    Pickrell, M.M.; Kendall, P.K.

    1994-01-01

    The authors have begun to develop a novel technique for active neutron assay of fissile material in spent nuclear fuel. This approach will exploit the unique operating features of a 14-MeV neutron generator developed by Schlumberger. This generator and a novel detection system will be applied to the direct measurement of the fissile material content in spent fuel in place of the indirect measures used at present. The technique they are investigating is termed synchronous active neutron detection (SAND). It closely follows a method that has been used routinely in other branches of physics to detect very small signals in the presence of large backgrounds. Synchronous detection instruments are widely available commercially and are termed open-quotes lock-inclose quotes amplifiers. The authors have implemented a digital lock-in amplifier in conjunction with the Schlumberger neutron generator to explore the possibility of synchronous detection with active neutrons. This approach is possible because the Schlumberger system can operate at up to a 50% duty factor, in effect, a square wave of neutron yield. The results to date are preliminary but quite promising. The system is capable of resolving the fissile material contained in a small fraction of the fuel rods in a cold fuel assembly. It also appears to be quite resilient to background neutron interference. The interrogating neutrons appear to be nonthermal and penetrating. Although a significant amount of work remains to fully explore the relevant physics and optimize the instrument design, the underlying concept appears sound

  1. A novel bicistronic sensor vector for detecting caspase-3 activation.

    Science.gov (United States)

    Vagner, Tatyana; Mouravlev, Alexandre; Young, Deborah

    2015-01-01

    Apoptosis is involved in pathological cell death of a wide range of human diseases. One of the most important biochemical markers of apoptosis is activation of caspase-3. Ability to detect caspase-3 activation early in the pathological process is important for determining the timing for interfering with apoptosis initiation and prevention of cell damage. Techniques allowing detection of caspase-3 activity at a single cell level show increased sensitivity, compared to biochemical assays; therefore, we developed a novel bicistronic caspase-3 sensor vector enabling detection of caspase-3 activity in individual cells. We employed green fluorescent protein (GFP) as a reporter for caspase-3 activation in our constructs and assessed the functionality of the generated constructs in transiently transfected Neuro2A and HEK293 cells under basal conditions and following application of okadaic acid (OA) or staurosporine (STS) to induce apoptosis. To ensure responsiveness of the new sensor vector to active caspase-3, we co-transfected the sensor with plasmid(s) overexpressing active caspase-3 and quantified GFP fluorescence using a plate reader. We observed an increase in GFP expression in cells transfected with the new bicistronic caspase-3 sensor in response to both OA and STS. We also showed a significant increase in GFP fluorescence intensity in cells co-expressing the sensor with the plasmid(s) encoding active caspase-3. We generated a novel bicistronic caspase-3 sensor vector which relies on a transcription factor/response element system. The obtained sensor combines high sensitivity of the single cell level detection with the possibility of automated quantification. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Detection of uranium enrichment activities using environmental monitoring techniques

    International Nuclear Information System (INIS)

    Belew, W.L.; Carter, J.A.; Smith, D.H.; Walker, R.L.

    1993-01-01

    Uranium enrichment processes have the capability of producing weapons-grade material in the form of highly enriched uranium. Thus, detection of undeclared uranium enrichment activities is an international safeguards concern. The uranium separation technologies currently in use employ UF 6 gas as a separation medium, and trace quantities of enriched uranium are inevitably released to the environment from these facilities. The isotopic content of uranium in the vegetation, soil, and water near the plant site will be altered by these releases and can provide a signature for detecting the presence of enriched uranium activities. This paper discusses environmental sampling and analytical procedures that have been used for the detection of uranium enrichment facilities and possible safeguards applications of these techniques

  3. Detection of uranium enrichment activities using environmental monitoring techniques

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.L.; Carter, J.A.; Smith, D.H.; Walker, R.L.

    1993-03-30

    Uranium enrichment processes have the capability of producing weapons-grade material in the form of highly enriched uranium. Thus, detection of undeclared uranium enrichment activities is an international safeguards concern. The uranium separation technologies currently in use employ UF{sub 6} gas as a separation medium, and trace quantities of enriched uranium are inevitably released to the environment from these facilities. The isotopic content of uranium in the vegetation, soil, and water near the plant site will be altered by these releases and can provide a signature for detecting the presence of enriched uranium activities. This paper discusses environmental sampling and analytical procedures that have been used for the detection of uranium enrichment facilities and possible safeguards applications of these techniques.

  4. Cracks Detection Using Active Modal Damping and Piezoelectric Components

    Directory of Open Access Journals (Sweden)

    B. Chomette

    2013-01-01

    Full Text Available The dynamics of a system and its safety can be considerably affected by the presence of cracks. Health monitoring strategies attract so a great deal of interest from industry. Cracks detection methods based on modal parameters variation are particularly efficient in the case of large cracks but are difficult to implement in the case of small cracks due to measurement difficulties in the case of small parameters variation. Therefore the present study proposes a new method to detect small cracks based on active modal damping and piezoelectric components. This method uses the active damping variation identificated with the Rational Fraction Polynomial algorithm as an indicator of cracks detection. The efficiency of the proposed method is demonstrated through numerical simulations corresponding to different crack depth and locations in the case of a finite element model of a clamped-clamped beam including four piezoelectric transducers.

  5. Realistic limitations of detecting planets around young active stars

    Directory of Open Access Journals (Sweden)

    Pinfield D.

    2013-04-01

    Full Text Available Current planet hunting methods using the radial velocity method are limited to observing middle-aged main-sequence stars where the signatures of stellar activity are much less than on young stars that have just arrived on the main-sequence. In this work we apply our knowledge from the surface imaging of these young stars to place realistic limitations on the possibility of detecting orbiting planets. In general we find that the magnitude of the stellar jitter is directly proportional to the stellar vsini. For G and K dwarfs, we find that it is possible, for models with high stellar activity and low stellar vsini, to be able to detect a 1 MJupiter mass planet within 50 epochs of observations and for the M dwarfs it is possible to detect a habitable zone Earth-like planet in 10s of observational epochs.

  6. Detection of efflux pump activity among clinical isolates of ...

    African Journals Online (AJOL)

    Purpose: To detect efflux pump activity (EPA) and screening a suspected efflux pump inhibitor (EPI) [1- (3-(trifluoromethyl)benzyl]-piperazine (TFMBP)], which could help in reducing multi-drug resistance (MDR). Methods: Eighteen isolates, viz, 14 S. aureus, 2 S. lentus, 1 S. xylosus and 1 Micrococcus species from various ...

  7. Detection of efflux pump activity among clinical isolates of ...

    African Journals Online (AJOL)

    Detection of efflux pump activity among clinical isolates of. Staphylococcus and Micrococcus ... Philadelphia, USA, 3Department of Medical Laboratory Science, College of Medicine, University of Lagos, Lagos, Nigeria. *For correspondence: Email: ... Eighteen clinical isolates comprising of 14 S. aureus, 2 S. lentus, 1 S.

  8. Active fire detection using Landsat 8 reflective bands

    Science.gov (United States)

    Sathyachandran, S. K.; Roy, D. P.

    2015-12-01

    Vegetation fires can alter landscapes and are a significant source of atmospheric emissions, particulates and greenhouse gases. Currently, only coarse spatial resolution sensors with high temporal coverage, such as MODIS or VIIRS, are used for routine global active fire mapping. Higher spatial resolution satellites have not been used due to their low temporal coverage and so are less useful for monitoring fires at the time of satellite overpass. However, looking forward, combination of the recently launched Landsat-8 (2013), Sentinel-2A (2015) and upcoming Sentinel-2B (2016) sensor data will provide 10-30m global coverage multi-spectral reflective wavelength observations approximately every three days. Therefore the development of reflective wavelength active fire detections to take advantage of these new data is highly attractive. Conventional detection algorithms use the elevated thermal emission of fire to detect the location of fires burning at the time of satellite overpass and apply contextual checks to remove commission errors by examination of neighboring pixels. A Landsat 8 active fire detection algorithm that takes advantage of the improved 12-bit radiometric resolution and high reflectance saturation of the Landsat 8 OLI detectors is presented. The algorithm uses the 1.6 μm and 2.2 μm bands without the need for a contextual implementation, or thermal bands, and was parameterized using six months of Landsat 8 data over the conterminous United States. Active fire detection results for Landsat 8 scenes acquired over a range of fire sizes and temperatures in Canada, Brazil and Southern Africa are presented and compared to detections found using an existing Landsat 7 contextual algorithm adapted to the Landsat 8 bands. Results show that the Landsat 8 algorithm has potential for global application, with relatively low omission and commission errors, and is suitable for application to the corresponding Sentinel 2 reflectance wavelength bands.

  9. An efficient voice activity detection algorithm by combining statistical model and energy detection

    Science.gov (United States)

    Wu, Ji; Zhang, Xiao-Lei

    2011-12-01

    In this article, we present a new voice activity detection (VAD) algorithm that is based on statistical models and empirical rule-based energy detection algorithm. Specifically, it needs two steps to separate speech segments from background noise. For the first step, the VAD detects possible speech endpoints efficiently using the empirical rule-based energy detection algorithm. However, the possible endpoints are not accurate enough when the signal-to-noise ratio is low. Therefore, for the second step, we propose a new gaussian mixture model-based multiple-observation log likelihood ratio algorithm to align the endpoints to their optimal positions. Several experiments are conducted to evaluate the proposed VAD on both accuracy and efficiency. The results show that it could achieve better performance than the six referenced VADs in various noise scenarios.

  10. An efficient voice activity detection algorithm by combining statistical model and energy detection

    Directory of Open Access Journals (Sweden)

    Wu Ji

    2011-01-01

    Full Text Available Abstract In this article, we present a new voice activity detection (VAD algorithm that is based on statistical models and empirical rule-based energy detection algorithm. Specifically, it needs two steps to separate speech segments from background noise. For the first step, the VAD detects possible speech endpoints efficiently using the empirical rule-based energy detection algorithm. However, the possible endpoints are not accurate enough when the signal-to-noise ratio is low. Therefore, for the second step, we propose a new gaussian mixture model-based multiple-observation log likelihood ratio algorithm to align the endpoints to their optimal positions. Several experiments are conducted to evaluate the proposed VAD on both accuracy and efficiency. The results show that it could achieve better performance than the six referenced VADs in various noise scenarios.

  11. Detecting Intermittent Steering Activity ; Development of a Phase-detection Algorithm

    NARCIS (Netherlands)

    Silva Peixoto de Aboim Chaves, H.M. da; Pauwelussen, J.J.A.; Mulder, M.; Paassen, M.M. van; Happee, R.; Mulder, M.

    2012-01-01

    Drivers usually maintain an error-neglecting control strategy (passive phase) in keeping their vehicle on the road, only to change to an error-correcting approach (active phase) when the vehicle state becomes inadequate. We developed an algorithm that is capable of detecting whether the driver is

  12. Tansig activation function (of MLP network) for cardiac abnormality detection

    Science.gov (United States)

    Adnan, Ja'afar; Daud, Nik Ghazali Nik; Ishak, Mohd Taufiq; Rizman, Zairi Ismael; Rahman, Muhammad Izzuddin Abd

    2018-02-01

    Heart abnormality often occurs regardless of gender, age and races. This problem sometimes does not show any symptoms and it can cause a sudden death to the patient. In general, heart abnormality is the irregular electrical activity of the heart. This paper attempts to develop a program that can detect heart abnormality activity through implementation of Multilayer Perceptron (MLP) network. A certain amount of data of the heartbeat signals from the electrocardiogram (ECG) will be used in this project to train the MLP network by using several training algorithms with Tansig activation function.

  13. Detection of Aspartic Proteinase Activities Using Gel Zymography.

    Science.gov (United States)

    Perera, Handunge Kumudu Irani

    2017-01-01

    Gel zymography is a two-stage process where the proteins from the test sample are first separated by electrophoresis followed by the detection of the activity of hydrolytic enzymes. Many zymography procedures use sodium dodecyl sulfate (SDS) polyacrylamide gels copolymerized with an appropriate substrate. The procedure described here uses native polyacrylamide gel electrophoresis (PAGE) in the absence of both SDS and substrate. In order to visualize aspartic proteinase activity, the gel is impregnated in bovine hemoglobin at pH 3.0 for 15 min after the electrophoresis procedure. Subsequently, the gel is incubated in a humid container in the absence of hemoglobin for 1 h at 37 °C. At the end, the gel is stained with amido black and destained. Clear areas against a dark background corresponding to aspartic proteinase activities can be detected.

  14. Voice Activity Detection Using Fuzzy Entropy and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    R. Johny Elton

    2016-08-01

    Full Text Available This paper proposes support vector machine (SVM based voice activity detection using FuzzyEn to improve detection performance under noisy conditions. The proposed voice activity detection (VAD uses fuzzy entropy (FuzzyEn as a feature extracted from noise-reduced speech signals to train an SVM model for speech/non-speech classification. The proposed VAD method was tested by conducting various experiments by adding real background noises of different signal-to-noise ratios (SNR ranging from −10 dB to 10 dB to actual speech signals collected from the TIMIT database. The analysis proves that FuzzyEn feature shows better results in discriminating noise and corrupted noisy speech. The efficacy of the SVM classifier was validated using 10-fold cross validation. Furthermore, the results obtained by the proposed method was compared with those of previous standardized VAD algorithms as well as recently developed methods. Performance comparison suggests that the proposed method is proven to be more efficient in detecting speech under various noisy environments with an accuracy of 93.29%, and the FuzzyEn feature detects speech efficiently even at low SNR levels.

  15. Verification of Minimum Detectable Activity for Radiological Threat Source Search

    Science.gov (United States)

    Gardiner, Hannah; Myjak, Mitchell; Baciak, James; Detwiler, Rebecca; Seifert, Carolyn

    2015-10-01

    The Department of Homeland Security's Domestic Nuclear Detection Office is working to develop advanced technologies that will improve the ability to detect, localize, and identify radiological and nuclear sources from airborne platforms. The Airborne Radiological Enhanced-sensor System (ARES) program is developing advanced data fusion algorithms for analyzing data from a helicopter-mounted radiation detector. This detector platform provides a rapid, wide-area assessment of radiological conditions at ground level. The NSCRAD (Nuisance-rejection Spectral Comparison Ratios for Anomaly Detection) algorithm was developed to distinguish low-count sources of interest from benign naturally occurring radiation and irrelevant nuisance sources. It uses a number of broad, overlapping regions of interest to statistically compare each newly measured spectrum with the current estimate for the background to identify anomalies. We recently developed a method to estimate the minimum detectable activity (MDA) of NSCRAD in real time. We present this method here and report on the MDA verification using both laboratory measurements and simulated injects on measured backgrounds at or near the detection limits. This work is supported by the US Department of Homeland Security, Domestic Nuclear Detection Office, under competitively awarded contract/IAA HSHQDC-12-X-00376. This support does not constitute an express or implied endorsement on the part of the Gov't.

  16. Ensemble spontaneous activity alterations detected by CISA approach.

    Science.gov (United States)

    Boudaoud, Sofiane; Rix, Hervé; Meste, Olivier; Cazals, Yves

    2007-01-01

    In this paper, we propose a method for detecting alterations in the Ensemble Spontaneous Activity (ESA), a random signal representing the composite spontaneous contribution of the auditory nerve recorded on the round window. The proposed method is based on shape analysis of the ESA amplitude histogram. For this task, we use a recent approach, the Corrected Integral Shape Averaging (CISA). Using this approach, a shape clustering algorithm is proposed to classify healthy and pathological ESA signals generated by a recent ESA model. This model allows a precise simulation of neural mechanisms occurring in the auditory nerve. The obtained results demonstrate that this shape analysis is very sensitive for detecting a small number of fibers with correlated firing, supposed to occur during a particular type of tinnitus. In comparison, the classical spectral index fails in this detection.

  17. Fast and direct detection of neuronal activation with diffusion MRI

    International Nuclear Information System (INIS)

    Le Bihan, D.; Urayama, S.; Aso, T.; Hanakawa, T.; Fukuyama, H.

    2006-01-01

    Over the last 30 years functional neuroimaging has emerged as a revolutionary path to study the brain and the mind. This has been possible because of significant advances mainly in two imaging modalities, namely Positron Emission Tomograph y (PET) and Magnetic Resonance Imaging (MRI). Amazingly, although those two modalities are based on radically different physical approaches (detection of 1 3 radioactivity for the first one and nuclear magnetization for the second), both allo w brain activation images to be obtained through measurements involving water molecules. So far, PET and MRI functional imaging have relied on the same principle that neuronal activation and blood flow are coupled through metabolism: Blood flow increases locally in activated brain regions. In the case of PET one uses H 2 O radioactive water which is produced by using a cyclotron and injected to the subject vasculature. In activated brain regions the increase in blood flow leads to a local increase in the tissue radioactive water content detected and localized by the PE T camera. With MRI the hydrogen nuclei of brain endogenous water molecules are magnetized by a strong external magnetic field. In activated regions the increase in blood flow results in an increase of blood oxygenation which induces a slight perturbation of the magnetization relaxation properties of the water molecules around blood vessels detected by the MRI scanner (so called 'BOLD' effect). I n both approaches water is, thus, merely an indirect means to look at changes in cerebral blood flow which accompany brain activation, and although PET and BOLD f MRI have been extremely successful for the functional neuroimaging community, present well known limitations. While the coupling between neuronal activation, metabolism and blood flow has been verified in most instances including BOLD f MRI, the degree and the mechanism of coupling remains largely debated (Magistratt, Pellerin, Mangia) and may fail in some pathological

  18. Noise Robust Voice Activity Detection Based on Switching Kalman Filter

    Science.gov (United States)

    Fujimoto, Masakiyo; Ishizuka, Kentaro

    This paper addresses the problem of voice activity detection (VAD) in noisy environments. The VAD method proposed in this paper is based on a statistical model approach, and estimates statistical models sequentially without a priori knowledge of noise. Namely, the proposed method constructs a clean speech/silence state transition model beforehand, and sequentially adapts the model to the noisy environment by using a switching Kalman filter when a signal is observed. In this paper, we carried out two evaluations. In the first, we observed that the proposed method significantly outperforms conventional methods as regards voice activity detection accuracy in simulated noise environments. Second, we evaluated the proposed method on a VAD evaluation framework, CENSREC-1-C. The evaluation results revealed that the proposed method significantly outperforms the baseline results of CENSREC-1-C as regards VAD accuracy in real environments. In addition, we confirmed that the proposed method helps to improve the accuracy of concatenated speech recognition in real environments.

  19. Phosphatase activity tunes two-component system sensor detection threshold.

    Science.gov (United States)

    Landry, Brian P; Palanki, Rohan; Dyulgyarov, Nikola; Hartsough, Lucas A; Tabor, Jeffrey J

    2018-04-12

    Two-component systems (TCSs) are the largest family of multi-step signal transduction pathways in biology, and a major source of sensors for biotechnology. However, the input concentrations to which biosensors respond are often mismatched with application requirements. Here, we utilize a mathematical model to show that TCS detection thresholds increase with the phosphatase activity of the sensor histidine kinase. We experimentally validate this result in engineered Bacillus subtilis nitrate and E. coli aspartate TCS sensors by tuning their detection threshold up to two orders of magnitude. We go on to apply our TCS tuning method to recently described tetrathionate and thiosulfate sensors by mutating a widely conserved residue previously shown to impact phosphatase activity. Finally, we apply TCS tuning to engineer B. subtilis to sense and report a wide range of fertilizer concentrations in soil. This work will enable the engineering of tailor-made biosensors for diverse synthetic biology applications.

  20. SVM detection of epileptiform activity in routine EEG.

    LENUS (Irish Health Repository)

    Kelleher, Daniel

    2010-01-01

    Routine electroencephalogram (EEG) is an important test in aiding the diagnosis of patients with suspected epilepsy. These recordings typically last 20-40 minutes, during which signs of abnormal activity (spikes, sharp waves) are looked for in the EEG trace. It is essential that events of short duration are detected during the routine EEG test. The work presented in this paper examines the effect of changing a range of input values to the detection system on its ability to distinguish between normal and abnormal EEG activity. It is shown that the length of analysis window in the range of 0.5s to 1s are well suited to the task. Additionally, it is reported that patient specific systems should be used where possible due to their better performance.

  1. A militarily fielded thermal neutron activation sensor for landmine detection

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, E.T.H. [Bubble Technology Industries, Chalk River (Canada); McFee, J.E. [Defence R and D Canada-Suffield, Medicine Hat (Canada)], E-mail: john.mcfee@drdc-rddc.gc.ca; Ing, H.; Andrews, H.R.; Tennant, D.; Harper, E. [Bubble Technology Industries, Chalk River (Canada); Faust, A.A. [Defence R and D Canada-Suffield, Medicine Hat (Canada)

    2007-08-21

    The Canadian Department of National Defence has developed a teleoperated, vehicle-mounted, multi-sensor system to detect anti-tank landmines on roads and tracks in peacekeeping operations. A key part of the system is a thermal neutron activation (TNA) sensor which is placed above a suspect location to within a 30 cm radius and confirms the presence of explosives via detection of the 10.835 MeV gamma ray associated with thermal neutron capture on {sup 14}N. The TNA uses a 100{mu}g{sup 252}Cf neutron source surrounded by four 7.62cmx7.62cm NaI(Tl) detectors. The system, consisting of the TNA sensor head, including source, detectors and shielding, the high-rate, fast pulse processing electronics and the data processing methodology are described. Results of experiments to characterize detection performance are also described. The experiments have shown that anti-tank mines buried 10 cm or less can be detected in roughly a minute or less, but deeper mines and mines significantly displaced horizontally take considerably longer time. Mines as deep as 30 cm can be detected for long count times (1000 s). Four TNA detectors are now in service with the Canadian Forces as part of the four multi-sensor systems, making it the first militarily fielded TNA sensor and the first militarily fielded confirmation sensor for landmines. The ability to function well in adverse climatic conditions has been demonstrated, both in trials and operations.

  2. Sensor to detect endothelialization on an active coronary stent

    Directory of Open Access Journals (Sweden)

    Coffey Arthur C

    2010-11-01

    Full Text Available Abstract Background A serious complication with drug-eluting coronary stents is late thrombosis, caused by exposed stent struts not covered by endothelial cells in the healing process. Real-time detection of this healing process could guide physicians for more individualized anti-platelet therapy. Here we present work towards developing a sensor to detect this healing process. Sensors on several stent struts could give information about the heterogeneity of healing across the stent. Methods A piezoelectric microcantilever was insulated with parylene and demonstrated as an endothelialization detector for incorporation within an active coronary stent. After initial characterization, endothelial cells were plated onto the cantilever surface. After they attached to the surface, they caused an increase in mass, and thus a decrease in the resonant frequencies of the cantilever. This shift was then detected electrically with an LCR meter. The self-sensing, self-actuating cantilever does not require an external, optical detection system, thus allowing for implanted applications. Results A cell density of 1300 cells/mm2 on the cantilever surface is detected. Conclusions We have developed a self-actuating, self-sensing device for detecting the presence of endothelial cells on a surface. The device is biocompatible and functions reliably in ionic liquids, making it appropriate for implantable applications. This sensor can be placed along the struts of a coronary stent to detect when the struts have been covered with a layer of endothelial cells and are no longer available surfaces for clot formation. Anti-platelet therapy can be adjusted in real-time with respect to a patient's level of healing and hemorrhaging risks.

  3. Detection of expansin proteins and activity during tomato fruit ontogeny.

    Science.gov (United States)

    Rose, J K; Cosgrove, D J; Albersheim, P; Darvill, A G; Bennett, A B

    2000-08-01

    Expansins are plant proteins that have the capacity to induce extension in isolated cell walls and are thought to mediate pH-dependent cell expansion. J.K.C. Rose, H.H. Lee, and A.B. Bennett ([1997] Proc Natl Acad Sci USA 94: 5955-5960) reported the identification of an expansin gene (LeExp1) that is specifically expressed in ripening tomato (Lycopersicon esculentum) fruit where cell wall disassembly, but not cell expansion, is prominent. Expansin expression during fruit ontogeny was examined using antibodies raised to recombinant LeExp1 or a cell elongation-related expansin from cucumber (CsExp1). The LeExp1 antiserum detected expansins in extracts from ripe, but not preripe tomato fruit, in agreement with the pattern of LeExp1 mRNA accumulation. In contrast, antibodies to CsExp1 cross-reacted with expansins in early fruit development and the onset of ripening, but not at a later ripening stage. These data suggest that ripening-related and expansion-related expansin proteins have distinct antigenic epitopes despite overall high sequence identity. Expansin proteins were detected in a range of fruit species and showed considerable variation in abundance; however, appreciable levels of expansin were not present in fruit of the rin or Nr tomato mutants that exhibit delayed and reduced softening. LeExp1 protein accumulation was ethylene-regulated and matched the previously described expression of mRNA, suggesting that expression is not regulated at the level of translation. We report the first detection of expansin activity in several stages of fruit development and while characteristic creep activity was detected in young and developing tomato fruit and in ripe pear, avocado, and pepper, creep activity in ripe tomato showed qualitative differences, suggesting both hydrolytic and expansin activities.

  4. INTEGRAL detects renewed activity from IGR J11435-6109

    DEFF Research Database (Denmark)

    Fiocchi, M.; Chenevez, J.; Sguera, V.

    2015-01-01

    During a recent INTEGRAL public observation of Musca region, performed between 2015-12-11 17:54 and 2015-12-12 12:54 (UTC), renewed activity from the transient X-ray pulsar IGR J11435-6109 has been detected. The 22-60 keV IBIS/ISGRI flux corresponds to (10+/-1) mCrab with an effective exposure ti...

  5. A Correlated Active Acoustic Leak Detection in a SFR Steam Generator

    International Nuclear Information System (INIS)

    Kim, Tae Joon; Jeong, Ji Young; Kim, Jong Man; Kim, Byung Ho; Kim, Yong Il

    2009-01-01

    The methods of acoustic leak detection are active acoustic leak detection and passive acoustic leak detection. The methods for passive acoustic leak detection are already established, but because our goal is development of passive acoustic leak detection for detecting a leakage range of small and micro leak rates, it is difficult detecting a leak in steam generator using this developed passive acoustic leak detection. Thus the acoustic leak detection system is required to be able to detect wide range of water leaks. From this view point we need to develop an active acoustic leak detection technology to be able to detect intermediate leak rates

  6. Magnetogastrographic detection of gastric electrical response activity in humans

    International Nuclear Information System (INIS)

    Irimia, Andrei; Richards, William O; Bradshaw, L Alan

    2006-01-01

    The detection and characterization of gastric electrical activity has important clinical applications, including the early diagnosis of gastric diseases in humans. In mammals, this phenomenon has two important features: an electrical control activity (ECA) that manifests itself as an electric slow wave (with a frequency of 3 cycles per minute in humans) and an electrical response activity (ERA) that is characterized by spiking potentials during the plateau phase of the ECA. Whereas the ECA has been recorded in humans both invasively and non-invasively (magnetogastrography-MGG), the ERA has never been detected non-invasively in humans before. In this paper, we report on our progress towards the non-invasive detection of ERA from the human stomach using a procedure that involves the application of principal component analysis to MGG recordings, which were acquired in our case from ten normal human patients using a Superconducting QUantum Interference Device (SQUID) magnetometer. Both pre- and post-prandial recordings were acquired for each patient and 20 min of recordings (10 min of pre-prandial and 10 min of post-prandial data) were analysed for each patient. The mean percentage of ECA slow waves that were found to exhibit spikes of suspected ERA origin was 41% and 61% for pre- and post-prandial recordings, respectively, implying a 47% ERA increase post-prandially (P < 0.0001 at a 95% confidence level). The detection of ERA in humans is highly encouraging and points to the possible use of non-invasive ERA recordings as a valuable tool for the study of human gastric disorders

  7. Detection of the under-soil intruder activity

    Science.gov (United States)

    Cechak, Jaroslav

    2007-04-01

    The presented paper focuses on the possibilities of technical methods designed to detect a trespasser under the ground, and in general on the possibilities of detection a trespasser behind an obstruction. The paper analyses method of detection of a trespasser that were practically verified by the author of the paper. The first part of the paper discusses the characteristics and use of piezoelectric films that could be used as a replacement for the traditional geophone for detection of underground mining operation. It also provides a block connection diagram of the measuring chain and photos of the practical implementation of the sensor. The consequent part of the paper then discusses the possibilities of detecting a trespasser based on electromagnetic waves emission by humans in the ELF - Extremely Low Frequency band. The paper is supplemented with illustrative photos and results of numeric processing of signals in the form of graphs and courses. The history of excavating and using tunnels spans long into the past. Tunnels were used not only as storage for food and war material but mainly as effective means of protection against attackers. A significant motivating factor for constructing tunnels lies in the hidden possibility of movement of people and transfer of material under the ground of a protected perimeter. At present some tunnels are used as roads for smuggling drugs, weapons, ammunition or illegal passages of people. There are even cases, not exceptional, when tunnels were excavated with the aim to rob a bank safe etc. The fact that construction of tunnels, often quite primitive ones, is not sporadic, can be continually documented not only by historical sources but often also by the daily news summary. The concurrent lack of proper technological means results in the renaissance of using tunnels for illegal purposes even at present. The presented paper focuses on the above mentioned area and points to little used physical principles of detection underground

  8. Improved thermal neutron activation sensor for detection of bulk explosives

    Science.gov (United States)

    McFee, John E.; Faust, Anthony A.; Andrews, H. Robert; Clifford, Edward T. H.; Mosquera, Cristian M.

    2012-06-01

    Defence R&D Canada - Suffield and Bubble Technology Industries have been developing thermal neutron activation (TNA) sensors for detection of buried bulk explosives since 1994. First generation sensors, employing an isotopic source and NaI(Tl) gamma ray detectors, were deployed by Canadian Forces in 2002 as confirmation sensors on the ILDS teleoperated, vehicle-mounted, multi-sensor anti-tank landmine detection systems. The first generation TNA could detect anti-tank mines buried 10 cm or less in no more than a minute, but deeper mines and those significantly displaced horizontally required considerably longer times. Mines as deep as 30 cm could be detected with long counting times (1000 s). The second generation TNA detector is being developed with a number of improvements aimed at increasing sensitivity and facilitating ease of operation. Among these are an electronic neutron generator to increase sensitivity for deeper and horizontally displaced explosives; LaBr3(Ce) scintillators, to improve time response and energy resolution; improved thermal and electronic stability; improved sensor head geometry to minimize spatial response nonuniformity; and more robust data processing. This improved sensitivity can translate to either decreased counting times, decreased minimum detectable explosive quantities, increased maximum sensor-to-target displacement, or a trade off among all three. Experiments to characterize the performance of the latest generation TNA in detecting buried landmines and IEDs hidden in culverts were conducted during 2011. This paper describes the second generation system. The experimental setup and methodology are detailed and preliminary comparisons between the performance of first and second generation systems are presented.

  9. Activation Detection in fMRI Using Jeffrey Divergence

    Science.gov (United States)

    Seghouane, Abd-Krim

    2009-12-01

    A statistical test for detecting activated pixels in functional MRI (fMRI) data is proposed. For the derivation of this test, the fMRI time series measured at each voxel is modeled as the sum of a response signal which arises due to the experimentally controlled activation-baseline pattern, a nuisance component representing effects of no interest, and Gaussian white noise. The test is based on comparing the dimension of the voxels fMRI time series fitted data models with and without controlled activation-baseline pattern. The Jeffrey divergence is used for this comparison. The test has the advantage of not requiring a level of significance or a threshold to be provided.

  10. Detection of Pesticides in Active and Depopulated Beehives in Uruguay

    Directory of Open Access Journals (Sweden)

    Horacio Heinzen

    2011-09-01

    Full Text Available The influence of insecticides commonly used for agricultural purposes on beehive depopulation in Uruguay was investigated. Honeycombs, bees, honey and propolis from depopulated hives were analyzed for pesticide residues, whereas from active beehives only honey and propolis were evaluated. A total of 37 samples were analyzed, representing 14,800 beehives. In depopulated beehives only imidacloprid and fipronil were detected and in active beehives endosulfan, coumaphos, cypermethrin, ethion and chlorpyrifos were found. Coumaphos was present in the highest concentrations, around 1,000 µg/kg, in all the propolis samples from active beehives. Regarding depopulated beehives, the mean levels of imidacloprid found in honeycomb (377 µg/kg, Standard Deviation: 118 and propolis (60 µg/kg, Standard Deviation: 57 are higher than those described to produce bee disorientation and fipronil levels detected in bees (150 and 170 µg/kg are toxic per se. The other insecticides found can affect the global fitness of the bees causing weakness and a decrease in their overall productivity. These preliminary results suggest that bees exposed to pesticides or its residues can lead them in different ways to the beehive.

  11. Detection of pesticides in active and depopulated beehives in Uruguay.

    Science.gov (United States)

    Pareja, Lucía; Colazzo, Marcos; Pérez-Parada, Andrés; Niell, Silvina; Carrasco-Letelier, Leonidas; Besil, Natalia; Cesio, María Verónica; Heinzen, Horacio

    2011-10-01

    The influence of insecticides commonly used for agricultural purposes on beehive depopulation in Uruguay was investigated. Honeycombs, bees, honey and propolis from depopulated hives were analyzed for pesticide residues, whereas from active beehives only honey and propolis were evaluated. A total of 37 samples were analyzed, representing 14,800 beehives. In depopulated beehives only imidacloprid and fipronil were detected and in active beehives endosulfan, coumaphos, cypermethrin, ethion and chlorpyrifos were found. Coumaphos was present in the highest concentrations, around 1,000 μg/kg, in all the propolis samples from active beehives. Regarding depopulated beehives, the mean levels of imidacloprid found in honeycomb (377 μg/kg, Standard Deviation: 118) and propolis (60 μg/kg, Standard Deviation: 57) are higher than those described to produce bee disorientation and fipronil levels detected in bees (150 and 170 μg/kg) are toxic per se. The other insecticides found can affect the global fitness of the bees causing weakness and a decrease in their overall productivity. These preliminary results suggest that bees exposed to pesticides or its residues can lead them in different ways to the beehive.

  12. Minimum Detectable Activity for Tomographic Gamma Scanning System

    Energy Technology Data Exchange (ETDEWEB)

    Venkataraman, Ram [Canberra Industries (AREVA BDNM), Meriden, CT (United States); Smith, Susan [Canberra Industries (AREVA BDNM), Meriden, CT (United States); Kirkpatrick, J. M. [Canberra Industries (AREVA BDNM), Meriden, CT (United States); Croft, Stephen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    For any radiation measurement system, it is useful to explore and establish the detection limits and a minimum detectable activity (MDA) for the radionuclides of interest, even if the system is to be used at far higher values. The MDA serves as an important figure of merit, and often a system is optimized and configured so that it can meet the MDA requirements of a measurement campaign. The non-destructive assay (NDA) systems based on gamma ray analysis are no exception and well established conventions, such the Currie method, exist for estimating the detection limits and the MDA. However, the Tomographic Gamma Scanning (TGS) technique poses some challenges for the estimation of detection limits and MDAs. The TGS combines high resolution gamma ray spectrometry (HRGS) with low spatial resolution image reconstruction techniques. In non-imaging gamma ray based NDA techniques measured counts in a full energy peak can be used to estimate the activity of a radionuclide, independently of other counting trials. However, in the case of the TGS each “view” is a full spectral grab (each a counting trial), and each scan consists of 150 spectral grabs in the transmission and emission scans per vertical layer of the item. The set of views in a complete scan are then used to solve for the radionuclide activities on a voxel by voxel basis, over 16 layers of a 10x10 voxel grid. Thus, the raw count data are not independent trials any more, but rather constitute input to a matrix solution for the emission image values at the various locations inside the item volume used in the reconstruction. So, the validity of the methods used to estimate MDA for an imaging technique such as TGS warrant a close scrutiny, because the pair-counting concept of Currie is not directly applicable. One can also raise questions as to whether the TGS, along with other image reconstruction techniques which heavily intertwine data, is a suitable method if one expects to measure samples whose activities

  13. Detection of biologically active diterpenoic acids by Raman Spectroscopy

    DEFF Research Database (Denmark)

    Talian, Ivan; Orinak, Andrej; Efremov, Evtim V.

    2010-01-01

    is not suitable for their unambiguous identification, especially not in solution. We attempted to increase the sensitivity by applying UV-resonance Raman spectroscopy and surface-enhanced Raman spectroscopy (SERS) techniques. The UV-Raman spectra of the three compounds in ethanol/water 50 : 50 showed only very......Three poorly detectable, biologically active diterpenoic acids, kaurenoic, abietic, and gibberellic acid, were studied by using different modes of Raman spectroscopy. Because of their structural similarities, in the absence of strongly polarizable groups, conventional Raman spectroscopy...

  14. Features for voice activity detection: a comparative analysis

    Science.gov (United States)

    Graf, Simon; Herbig, Tobias; Buck, Markus; Schmidt, Gerhard

    2015-12-01

    In many speech signal processing applications, voice activity detection (VAD) plays an essential role for separating an audio stream into time intervals that contain speech activity and time intervals where speech is absent. Many features that reflect the presence of speech were introduced in literature. However, to our knowledge, no extensive comparison has been provided yet. In this article, we therefore present a structured overview of several established VAD features that target at different properties of speech. We categorize the features with respect to properties that are exploited, such as power, harmonicity, or modulation, and evaluate the performance of some dedicated features. The importance of temporal context is discussed in relation to latency restrictions imposed by different applications. Our analyses allow for selecting promising VAD features and finding a reasonable trade-off between performance and complexity.

  15. Sub-surface defects detection of by using active thermography and advanced image edge detection

    International Nuclear Information System (INIS)

    Tse, Peter W.; Wang, Gaochao

    2017-01-01

    Active or pulsed thermography is a popular non-destructive testing (NDT) tool for inspecting the integrity and anomaly of industrial equipment. One of the recent research trends in using active thermography is to automate the process in detecting hidden defects. As of today, human effort has still been using to adjust the temperature intensity of the thermo camera in order to visually observe the difference in cooling rates caused by a normal target as compared to that by a sub-surface crack exists inside the target. To avoid the tedious human-visual inspection and minimize human induced error, this paper reports the design of an automatic method that is capable of detecting subsurface defects. The method used the technique of active thermography, edge detection in machine vision and smart algorithm. An infrared thermo-camera was used to capture a series of temporal pictures after slightly heating up the inspected target by flash lamps. Then the Canny edge detector was employed to automatically extract the defect related images from the captured pictures. The captured temporal pictures were preprocessed by a packet of Canny edge detector and then a smart algorithm was used to reconstruct the whole sequences of image signals. During the processes, noise and irrelevant backgrounds exist in the pictures were removed. Consequently, the contrast of the edges of defective areas had been highlighted. The designed automatic method was verified by real pipe specimens that contains sub-surface cracks. After applying such smart method, the edges of cracks can be revealed visually without the need of using manual adjustment on the setting of thermo-camera. With the help of this automatic method, the tedious process in manually adjusting the colour contract and the pixel intensity in order to reveal defects can be avoided. (paper)

  16. Adhesive disbond detection using piezoelectric wafer active sensors

    Science.gov (United States)

    Roth, William; Giurgiutiu, Victor

    2015-04-01

    The aerospace industry continues to increase the use of adhesives for structural bonding due to the increased joint efficiency (reduced weight), even distribution of the load path and decreases in stress concentrations. However, the limited techniques for verifying the strength of adhesive bonds has reduced its use on primary structures and requires an intensive inspection schedule. This paper discusses a potential structural health monitoring (SHM) technique for the detection of disbonds through the in situ inspection of adhesive joints. This is achieved through the use of piezoelectric wafer active sensors (PWAS), thin unobtrusive sensors which are permanently bonded to the aircraft structure. The detection method discussed in this study is electromechanical impedance spectroscopy (EMIS), a local vibration method. This method detects disbonds from the change in the mechanical impedance of the structure surrounding the disbond. This paper will discuss how predictive modeling can provide valuable insight into the inspection method, and provide better results than empirical methods alone. The inspection scheme was evaluated using the finite element method, and the results were verified experimentally using a large aluminum test article, and included both pristine and disbond coupons.

  17. Fast and direct detection of neuronal activation with diffusion MRI

    Energy Technology Data Exchange (ETDEWEB)

    Le Bihan, D. [Service Hospitalier Frederic Joliot (CEA/DSV/DRM), Lab. Anatomical and Functional Neuroimaging, 91 - Orsay (France); Urayama, S.; Aso, T.; Hanakawa, T.; Fukuyama, H. [Kyoto Univ. Graduate School of Medicine, Human Brain Research Center, Kyoto (Japan)

    2006-07-01

    Over the last 30 years functional neuroimaging has emerged as a revolutionary path to study the brain and the mind. This has been possible because of significant advances mainly in two imaging modalities, namely Positron Emission Tomograph y (PET) and Magnetic Resonance Imaging (MRI). Amazingly, although those two modalities are based on radically different physical approaches (detection of 1 3 radioactivity for the first one and nuclear magnetization for the second), both allo w brain activation images to be obtained through measurements involving water molecules. So far, PET and MRI functional imaging have relied on the same principle that neuronal activation and blood flow are coupled through metabolism: Blood flow increases locally in activated brain regions. In the case of PET one uses H{sub 2}O radioactive water which is produced by using a cyclotron and injected to the subject vasculature. In activated brain regions the increase in blood flow leads to a local increase in the tissue radioactive water content detected and localized by the PE T camera. With MRI the hydrogen nuclei of brain endogenous water molecules are magnetized by a strong external magnetic field. In activated regions the increase in blood flow results in an increase of blood oxygenation which induces a slight perturbation of the magnetization relaxation properties of the water molecules around blood vessels detected by the MRI scanner (so called 'BOLD' effect). I n both approaches water is, thus, merely an indirect means to look at changes in cerebral blood flow which accompany brain activation, and although PET and BOLD f MRI have been extremely successful for the functional neuroimaging community, present well known limitations. While the coupling between neuronal activation, metabolism and blood flow has been verified in most instances including BOLD f MRI, the degree and the mechanism of coupling remains largely debated (Magistratt, Pellerin, Mangia) and may fail in some

  18. In situ autoradiographic detection of folylpolyglutamate synthetase activity

    International Nuclear Information System (INIS)

    Sussman, D.J.; Milman, G.; Osborne, C.; Shane, B.

    1986-01-01

    The enzyme folylpolyglutamate synthetase (FPGS) catalyzes the conversion of folate (pteroylmonoglutamate) to the polyglutamate forms (pteroylpolyglutamates) that are required for folate retention by mammalian cells. A rapid in situ autoradiographic assay for FPGS was developed which is based on the folate cofactor requirement of thymidylate synthase. Chinese hamster AUX B1 mutant cells lack FPGS activity and are unable to accumulate folate. As a result, the conversion of [6- 3 H]deoxyuridine to thymidine via the thymidylate synthase reaction is impaired in AUX B1 cells and no detectable label is incorporated into DNA. In contrast, FPGS in wild-type Chinese hamster CHO cells causes folate retention and enables the incorporation of [6- 3 H]deoxyuridine into DNA. Incorporation may be detected by autoradiography of monolayer cultures or of colonies replica plated onto polyester discs. Introduction of Escherichia coli FPGS into AUX B1 cells restores the activity of the thymidylate synthase pathway and demonstrates that the E. coli FPGS enzyme can provide pteroylpolyglutamates which functions in mammalian cells

  19. IAEA safeguards and detection of undeclared nuclear activities

    International Nuclear Information System (INIS)

    Harry, R.J.S.

    1996-03-01

    Verfication of State declarations is an essential feature of IAEA safeguards. The issue of completeness of the declaration of all nuclear material, nuclear activities and nuclear facilities arises only in full scope safeguards, like those pursuant to NPT. Concentrating on the accountability aspect of nuclear material, the NPT safeguards system has achieved a high level of objective and quantified performance. Some of the basic ideas of the drafters of INFCIRC/153 (corrected) have been stalled. Non-proliferation concerns demand also for a detection probability for undeclared nuclear activities. Following the example of the Chemical Weapon Convention (CWC), advanced detection techniques are proposed, which go beyond the classical nuclear material accountability approach. Recent proposals for additional measures to strengthen IAEA safeguards conform to rules of NPT and related safeguards. Some proposals have been agreed generally, others can only be implemented on a voluntary basis between the State and the IAEA. The implementation will require additional resources and support for the IAEA. Great care is required to maintain the existing capability of the IAEA for a technically sound, independent, objective, and internationally acceptable judgement with available resources, and at the same time to change emphasis on certain elements of the existing safeguards system. (orig.)

  20. Learning patterns of human activity for anomaly detection

    Science.gov (United States)

    Gutchess, Daniel; Checka, Neal; Snorrason, Magnús S.

    2007-04-01

    Commercial security and surveillance systems offer advanced sensors, optics, and display capabilities but lack intelligent processing. This necessitates human operators who must closely monitor video for situational awareness and threat assessment. For instance, urban environments are typically in a state of constant activity, which generates numerous visual cues, each of which must be examined so that potential security breaches do not go unnoticed. We are building a prototype system called BALDUR (Behavior Adaptive Learning during Urban Reconnaissance) that learns probabilistic models of activity for a given site using online and unsupervised training techniques. Once a camera system is set up, no operator intervention is required for the system to begin learning patterns of activity. Anomalies corresponding to unusual or suspicious behavior are automatically detected in real time. All moving object tracks (pedestrians, vehicles, etc.) are efficiently stored in a relational database for use in training. The database is also well suited for answering human- initiated queries. An example of such a query is, "Display all pedestrians who approached the door of the building between the hours of 9:00pm and 11:00pm." This forensic analysis tool complements the system's real-time situational awareness capabilities. Several large datasets have been collected for the evaluation of the system, including one database containing an entire month of activity from a commercial parking lot.

  1. Detection of telomerase activity in gastric lavage fluid: a novel method to detect gastric cancer.

    Science.gov (United States)

    Wong, Stephen Ching-ho; Yu, Hanry; So, Jimmy B Y

    2006-04-01

    Telomerase is a ribonucleoprotein polymerase that is essential for cell immortality. Recent studies have demonstrated that a high percentage of gastric cancer tissue expressed telomerase. This study describes the presence of telomerase activity in gastric lavage fluid in patients with gastric cancer. Gastric lavage fluid was collected during esophageogastroduodenoscopy in 70 patients: 25 with gastric cancer, 25 with peptic ulcer disease, and 20 with normal stomach. The fluid and biopsy samples were analyzed for telomerase activity by a polymerase chain reaction-based telomerase repeat amplification protocol. The findings were related to the histological results. Telomerase activity was present in 24 of the 25 (96%) gastric cancer tissue and in 7 of the 25 tissue specimens from peptic ulcer or gastritis. In the gastric lavage fluid, telomerase was detected in 20 patients (80%) with gastric cancer, 7 patients (28%) with peptic ulcer, and none in normal subjects (P < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value of gastric fluid telomerase expression in gastric cancer patients was 80%, 84%, 74%, and 88%, respectively. The presence of telomerase activity is present in gastric lavage fluid of patients with gastric cancer as compared to those without, may represent a novel method for diagnosis of gastric cancer.

  2. Brain Activation Underlying Threat Detection to Targets of Different Races

    Science.gov (United States)

    Senholzi, Keith B.; Depue, Brendan E.; Correll, Joshua; Banich, Marie T.; Ito, Tiffany A.

    2016-01-01

    The current study examined blood oxygen level dependent (BOLD) signal underlying racial differences in threat detection. During fMRI, participants determined whether pictures of Black or White individuals held weapons. They were instructed to make shoot responses when the picture showed armed individuals but don’t shoot responses to unarmed individuals, with the cost of not shooting armed individuals being greater than that of shooting unarmed individuals. Participants were faster to shoot armed Blacks than Whites, but faster in making don’t shoot responses to unarmed Whites than Blacks. Brain activity differed to armed versus unarmed targets depending on target race, suggesting different mechanisms underlying threat versus safety decisions. Anterior cingulate cortex was preferentially engaged for unarmed Whites than Blacks. Parietal and visual cortical regions exhibited greater activity for armed Blacks than Whites. Seed-based functional connectivity of the amygdala revealed greater coherence with parietal and visual cortices for armed Blacks than Whites. Furthermore, greater implicit Black-danger associations were associated with increased amygdala activation to armed Blacks, compared to armed Whites. Our results suggest that different neural mechanisms may underlie racial differences in responses to armed versus unarmed targets. PMID:26357911

  3. Detection of nuclear material by photon activation inside cargo containers

    Science.gov (United States)

    Gmar, Mehdi; Berthoumieux, Eric; Boyer, Sébastien; Carrel, Frédérick; Doré, Diane; Giacri, Marie-Laure; Lainé, Frédéric; Poumarède, Bénédicte; Ridikas, Danas; Van Lauwe, Aymeric

    2006-05-01

    Photons with energies above 6 MeV can be used to detect small amounts of nuclear material inside large cargo containers. The method consists in using an intense beam of high-energy photons (bremsstrahlung radiation) in order to induce reactions of photofission on actinides. The measurement of delayed neutrons and delayed gammas emitted by fission products brings specific information on localization and quantification of the nuclear material. A simultaneous measurement of both of these delayed signals can overcome some important limitations due to matrix effects like heavy shielding and/or the presence of light elements as hydrogen. We have a long experience in the field of nuclear waste package characterization by photon interrogation and we have demonstrated that presently the detection limit can be less than one gram of actinide per ton of package. Recently we tried to extend our knowledge to assess the performance of this method for the detection of special nuclear materials in sea and air freights. This paper presents our first results based on experimental measurements carried out in the SAPHIR facility, which houses a linear electron accelerator with the energy range from 15 MeV to 30 MeV. Our experiments were also modeled using the full scale Monte Carlo techniques. In addition, and in a more general frame, due to the lack of consistent data on photonuclear reactions, we have been working on the development of a new photonuclear activation file (PAF), which includes cross sections for more than 600 isotopes including photofission fragment distributions and delayed neutron tables for actinides. Therefore, this work includes also some experimental results obtained at the ELSA electron accelerator, which is more adapted for precise basic nuclear data measurements.

  4. Voice activity detection based on deep neural networks and Viterbi

    Science.gov (United States)

    Bai, Liang; Zhang, Zhen; Hu, Jun

    2017-09-01

    Voice Activity Detection (VAD) is important in speech processing. In the applications, the systems usually need to separate speech/non-speech parts, so that only the speech part can be dealt with. How to improve the performances of VAD in different noisy environments is an important issue in speech processing. Deep Neural network, which proves its efficiency in speech recognition, has been widely used in recent years. This paper studies the present typical VAD algorithms, and presents a new VAD algorithm based on deep neural networks and Viterbi algorithm. The result demonstrates the effectiveness of the deep neural network with Viterbi used in VAD. In addition, it shows the flexibility and the real-time performance of the algorithms.

  5. Voice activity detection algorithm using perceptual wavelet entropy neighbor slope.

    Science.gov (United States)

    Lee, Gihyoun; Na, Sung Dae; Cho, Jin-Ho; Kim, Myoung Nam

    2014-01-01

    This paper presents a voice activity detection (VAD) approach using a perceptual wavelet entropy neighbor slope (PWENS) in a low signal-to-noise (SNR) environment and with a variety of noise types. The basis for our study is to use acoustic features that have large entropy variance for each wavelet critical band. The speech signal is decomposed by the proposed perceptual wavelet packet decomposition (PWPD), and the VAD function is extracted by PWENS. Finally, VAD is decided by the proposed VAD decision rule using two memory buffers. In order to evaluate the performance of the VAD decision, many speech samples and a variety of SNR conditions were used in the experiment. The performance of the VAD decision is confirmed using objective indexes such as a graph of the VAD decision and the relative error rate.

  6. Pipeline oil fire detection with MODIS active fire products

    Science.gov (United States)

    Ogungbuyi, M. G.; Martinez, P.; Eckardt, F. D.

    2017-12-01

    We investigate 85 129 MODIS satellite active fire events from 2007 to 2015 in the Niger Delta of Nigeria. The region is the oil base for Nigerian economy and the hub of oil exploration where oil facilities (i.e. flowlines, flow stations, trunklines, oil wells and oil fields) are domiciled, and from where crude oil and refined products are transported to different Nigerian locations through a network of pipeline systems. Pipeline and other oil facilities are consistently susceptible to oil leaks due to operational or maintenance error, and by acts of deliberate sabotage of the pipeline equipment which often result in explosions and fire outbreaks. We used ground oil spill reports obtained from the National Oil Spill Detection and Response Agency (NOSDRA) database (see www.oilspillmonitor.ng) to validate MODIS satellite data. NOSDRA database shows an estimate of 10 000 spill events from 2007 - 2015. The spill events were filtered to include largest spills by volume and events occurring only in the Niger Delta (i.e. 386 spills). By projecting both MODIS fire and spill as `input vector' layers with `Points' geometry, and the Nigerian pipeline networks as `from vector' layers with `LineString' geometry in a geographical information system, we extracted the nearest MODIS events (i.e. 2192) closed to the pipelines by 1000m distance in spatial vector analysis. The extraction process that defined the nearest distance to the pipelines is based on the global practices of the Right of Way (ROW) in pipeline management that earmarked 30m strip of land to the pipeline. The KML files of the extracted fires in a Google map validated their source origin to be from oil facilities. Land cover mapping confirmed fire anomalies. The aim of the study is to propose a near-real-time monitoring of spill events along pipeline routes using 250 m spatial resolution of MODIS active fire detection sensor when such spills are accompanied by fire events in the study location.

  7. Improved Active Harmonic Current Elimination Based on Voltage Detection.

    Directory of Open Access Journals (Sweden)

    Tianyuan Tan

    Full Text Available With the increasing penetration of power electronic equipment in modern residential distribution systems, harmonics mitigation through the distributed generation (DG interfacing converters has received significant attention. Among recently proposed methods, the so-called active resonance damper (ARD and harmonic voltage compensator (HVC based on voltage detection can effectively reduce the harmonic distortions in selected areas of distribution systems. However, it is found out that when traditional ARD algorithm is used to eliminate harmonic current injected by non-linear loads, its performance is constrained by stability problems and can at most eliminate half of the load harmonic currents. Thus, inspired by the duality between ARD and HVC, this paper presents a novel improved resistive active power filter (R-APF algorithm based on integral-decoupling control. The design guideline for its parameters is then investigated through carefully analyzing the closed-loop poles' trajectory. Computer studies demonstrate that the proposed algorithm can effectively mitigate the load harmonic currents and its performance is much better than traditional ARD based on proportional control.

  8. Improved Active Harmonic Current Elimination Based on Voltage Detection.

    Science.gov (United States)

    Tan, Tianyuan; Dong, Shuan; Huang, Yingwei; Liu, Jian; Le, Jian; Liu, Kaipei

    2016-01-01

    With the increasing penetration of power electronic equipment in modern residential distribution systems, harmonics mitigation through the distributed generation (DG) interfacing converters has received significant attention. Among recently proposed methods, the so-called active resonance damper (ARD) and harmonic voltage compensator (HVC) based on voltage detection can effectively reduce the harmonic distortions in selected areas of distribution systems. However, it is found out that when traditional ARD algorithm is used to eliminate harmonic current injected by non-linear loads, its performance is constrained by stability problems and can at most eliminate half of the load harmonic currents. Thus, inspired by the duality between ARD and HVC, this paper presents a novel improved resistive active power filter (R-APF) algorithm based on integral-decoupling control. The design guideline for its parameters is then investigated through carefully analyzing the closed-loop poles' trajectory. Computer studies demonstrate that the proposed algorithm can effectively mitigate the load harmonic currents and its performance is much better than traditional ARD based on proportional control.

  9. Oral-Fluid Thiol-Detection Test Identifies Underlying Active Periodontal Disease Not Detected by the Visual Awake Examination.

    Science.gov (United States)

    Queck, Katherine E; Chapman, Angela; Herzog, Leslie J; Shell-Martin, Tamara; Burgess-Cassler, Anthony; McClure, George David

    2018-03-20

    Periodontal disease in dogs is highly prevalent but can only be accurately diagnosed by performing an anesthetized oral examination with periodontal probing and dental radiography. In this study, 114 dogs had a visual awake examination of the oral cavity and were administered an oral-fluid thiol-detection test prior to undergoing a a full-mouth anesthetized oral examination and digital dental radiographs. The results show the visual awake examination underestimated the presence and severity of active periodontal disease. The thiol-detection test was superior to the visual awake examination at detecting the presence and severity of active periodontal disease and was an indicator of progression toward alveolar bone loss. The thiol-detection test detected active periodontal disease at early stages of development, before any visual cues were present, indicating the need for intervention to prevent periodontal bone loss. Early detection is important because without intervention, dogs with gingivitis (active periodontal disease) progress to irreversible periodontal bone loss (stage 2+). As suggested in the current AAHA guidelines, a thiol-detection test administered in conjunction with the visual awake examination during routine wellness examinations facilitates veterinarian-client communication and mitigates under-diagnosis of periodontal disease and underutilization of dental services. The thiol-detection test can be used to monitor the periodontal health status of the conscious patient during follow-up examinations based on disease severity.

  10. Polyamidoamine starburst dendrimer-activated chromatography paper-based assay for sensitive detection of telomerase activity.

    Science.gov (United States)

    Zhang, Hua; Lei, Zhen; Tian, Rongrong; Wang, Zhenxin

    2018-02-01

    Telomerase is extensively expressed in various cancer cells and recognized as a target for cancer drug discovery. In the present study, a simple and amplification-free fluorescence assay based on polyamidoamine starburst dendrimer (PAMAM dendrimer)-activated paper device is proposed for sensitive detection of telomerase activity through hybridization of Cy5 modified single strand DNA probes with telomerase extension products. The paper substrate is fabricated by hand drawing according to a template, which is low cost, instrument free and easy operation. PAMAM is rich in amino groups on its surface and employed to immobilize the telomerase substrate (TS) primer. Highly sensitive detection of telomerase activity in HeLa cell lysate of 10 cells is achieved since the PAMAM dendrimer-activated paper surface can provide high density of binding sites for immobilization of TS primer. The experimental results also demonstrate that the assay can be employed to evaluate telomerase activity levels of various cell lines and screen telomerase inhibitors. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Detection of activated platelets using activation-specific monoclonal antibody (SZ-51) in clinical disorders

    International Nuclear Information System (INIS)

    Wu Guoxin; Li Fugang; Li Jianyong; Ruan Changgeng

    1991-10-01

    A direct test for activated platelets in whole blood was developed by radioimmunoassay with 125 I labeled SZ-51, an antibody specific for an α-granule membrane protein (GMP-140) that associates with the platelet surface during secretion. The assay had sufficient sensitivity to detect as few as 2% activated platelets. In 50 normal subjects, minimal GMP-140 molecules per platelet were expressed on the surface of circulating platelets. Ten patients undergoing cardiopulmonary bypass had transiently increased expression of GMP-140 molecules during the bypass procedure, especially at the end of bypass. Evaluation of 18 patients with epidemic hemorrhagic fever (EHF) has shown that the number of GMP-140 molecules on the platelet surface was closely related to the four different phases of EHF. In six patients suffered from acute myocardial infarction (AMI), the number of GMP-140 molecules changed with the procession of AMI and the highest occurred 48 h after AMI. The GMP-140 molecules were also increased in patients with asthma attack (n = 14), but not in patients with idiopathic thrombocytopenic purpura (n = 11) and diabetic mellitus (n = 48). Taken together, these studies suggest that activated platelet can be reliably measured in whole blood using radiolabeled SZ-51 antibody and the detection of activated platelets is potentially useful in identifying patients with certain thrombotic disorders and others

  12. Step detection and activity recognition accuracy of seven physical activity monitors.

    Directory of Open Access Journals (Sweden)

    Fabio A Storm

    Full Text Available The aim of this study was to compare the seven following commercially available activity monitors in terms of step count detection accuracy: Movemonitor (Mc Roberts, Up (Jawbone, One (Fitbit, ActivPAL (PAL Technologies Ltd., Nike+ Fuelband (Nike Inc., Tractivity (Kineteks Corp. and Sensewear Armband Mini (Bodymedia. Sixteen healthy adults consented to take part in the study. The experimental protocol included walking along an indoor straight walkway, descending and ascending 24 steps, free outdoor walking and free indoor walking. These tasks were repeated at three self-selected walking speeds. Angular velocity signals collected at both shanks using two wireless inertial measurement units (OPAL, ADPM Inc were used as a reference for the step count, computed using previously validated algorithms. Step detection accuracy was assessed using the mean absolute percentage error computed for each sensor. The Movemonitor and the ActivPAL were also tested within a nine-minute activity recognition protocol, during which the participants performed a set of complex tasks. Posture classifications were obtained from the two monitors and expressed as a percentage of the total task duration. The Movemonitor, One, ActivPAL, Nike+ Fuelband and Sensewear Armband Mini underestimated the number of steps in all the observed walking speeds, whereas the Tractivity significantly overestimated step count. The Movemonitor was the best performing sensor, with an error lower than 2% at all speeds and the smallest error obtained in the outdoor walking. The activity recognition protocol showed that the Movemonitor performed best in the walking recognition, but had difficulty in discriminating between standing and sitting. Results of this study can be used to inform choice of a monitor for specific applications.

  13. Step detection and activity recognition accuracy of seven physical activity monitors.

    Science.gov (United States)

    Storm, Fabio A; Heller, Ben W; Mazzà, Claudia

    2015-01-01

    The aim of this study was to compare the seven following commercially available activity monitors in terms of step count detection accuracy: Movemonitor (Mc Roberts), Up (Jawbone), One (Fitbit), ActivPAL (PAL Technologies Ltd.), Nike+ Fuelband (Nike Inc.), Tractivity (Kineteks Corp.) and Sensewear Armband Mini (Bodymedia). Sixteen healthy adults consented to take part in the study. The experimental protocol included walking along an indoor straight walkway, descending and ascending 24 steps, free outdoor walking and free indoor walking. These tasks were repeated at three self-selected walking speeds. Angular velocity signals collected at both shanks using two wireless inertial measurement units (OPAL, ADPM Inc) were used as a reference for the step count, computed using previously validated algorithms. Step detection accuracy was assessed using the mean absolute percentage error computed for each sensor. The Movemonitor and the ActivPAL were also tested within a nine-minute activity recognition protocol, during which the participants performed a set of complex tasks. Posture classifications were obtained from the two monitors and expressed as a percentage of the total task duration. The Movemonitor, One, ActivPAL, Nike+ Fuelband and Sensewear Armband Mini underestimated the number of steps in all the observed walking speeds, whereas the Tractivity significantly overestimated step count. The Movemonitor was the best performing sensor, with an error lower than 2% at all speeds and the smallest error obtained in the outdoor walking. The activity recognition protocol showed that the Movemonitor performed best in the walking recognition, but had difficulty in discriminating between standing and sitting. Results of this study can be used to inform choice of a monitor for specific applications.

  14. Biomarkers for the detection, prognois and evaluation of active tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Shinimukundan, Harshini [Los Alamos National Laboratory

    2010-12-08

    The global TS surveillance workshop aims to address the problems with current methods for the detection of TB, and tracking emergence of resistant strains. The purpose of the attached presentation is to review the current methods in the detection of pathogen biomarkers for TB and if that technology has promise for diagnosis of TB. A summary of three biomarkers and some data on their detection strategies is presented. Some of the work is from LANL work but much of it is derived from literature references on the subject.

  15. Comparison of symptoms and treatment outcomes between actively and passively detected tuberculosis cases: the additional value of active case finding

    NARCIS (Netherlands)

    den Boon, S.; Verver, S.; Lombard, C. J.; Bateman, E. D.; Irusen, E. M.; Enarson, D. A.; Borgdorff, M. W.; Beyers, N.

    2008-01-01

    Passive detection of tuberculosis (TB) cases may lead to delay in treatment which may contribute to increased severity of(disease and mortality. Active case finding may be an alternative. In a community survey in Cape Town, South Africa, we actively detected 27 bacteriologically positive TB cases

  16. Pro-active data breach detection: examining accuracy and applicability on personal information detected

    CSIR Research Space (South Africa)

    Botha, J

    2016-03-01

    Full Text Available or negligence will stop unless effective enforcement of relevant legislation is applied. While several information privacy regulators exist, the dominant norm is to respond reactively on reported incidents. Reactive response is useful for cleaning up detected...

  17. Detection activity assessment and diagnosis of dental caries lesions

    DEFF Research Database (Denmark)

    Braga, Mariana M; Mendes, Fausto M; Ekstrand, Kim R

    2010-01-01

    This article reviews the current methods for detection and assessment of caries lesions focusing on applicability for daily clinical practice. The end point is to arrive at a diagnosis for each caries lesion. Visual inspection aided by a ball-ended probe is essential for caries lesions assessment...

  18. INTEGRAL non detection of renewed activity from Terzan 5

    DEFF Research Database (Denmark)

    Vovk, I.; Kuulkers, E.; Chenevez, Jérôme

    2011-01-01

    The Globular Cluster Terzan5, was observed by the IBIS/ISGRI and JEM-X instruments on-board INTEGRAL during the Galactic Bulge monitoring program (ATel #438) from 2011 October 25 at 17:15 to 2011 October 25 at 20:56 (UTC). No significant X-ray emission was detected in the direction of the Globula...

  19. Detection of Extracellular Enzyme Activities in Ganoderma neo-japonicum

    OpenAIRE

    Jo, Woo-Sik; Park, Ha-Na; Cho, Doo-Hyun; Yoo, Young-Bok; Park, Seung-Chun

    2011-01-01

    The ability of Ganoderma to produce extracellular enzymes, including β-glucosidase, cellulase, avicelase, pectinase, xylanase, protease, amylase, and ligninase was tested in chromogenic media. β-glucosidase showed the highest activity, among the eight tested enzymes. In particular, Ganoderma neo-japonicum showed significantly stronger activity for β-glucosidase than that of the other enzymes. Two Ganoderma lucidum isolates showed moderate activity for avicelase; however, Ganoderma neo-japonic...

  20. Detection of silent intervals between noises activating different perceptual channels: some properties of "central" auditory gap detection.

    Science.gov (United States)

    Phillips, D P; Taylor, T L; Hall, S E; Carr, M M; Mossop, J E

    1997-06-01

    This article describes four experiments on gap detection by normal listeners, with the general goal being to examine the consequences of using noises in different perceptual channels to delimit a silent temporal gap to be detected. In experiment 1, subjects were presented with pairs of narrow-band noise sequences. The leading element in each pair had a center frequency of 2 kHz and the trailing element's center frequency was parametrically varied. Gap detection thresholds became increasingly poor, sometimes by up to an order of magnitude, as the spectral disparity was increased between the noise bursts that marked the gap. These data suggested that gap-detection performance is impoverished when the underlying perceptual timing operation requires a comparison of activity in different perceptual channels rather than a discontinuity detection within a given channel. In experiment 2, we assessed the effect of leading-element duration in within-channel and between-channel gap detection tasks. Gap detection thresholds rose when the duration of the leading element was less than about 30 ms, but only in the between-channel case. In experiment 3, the gap-detection stimulus was redesigned so that we could probe the perceptual mechanisms that might be involved in stop consonant discrimination. The leading element was a wideband noise burst, and the trailing element was a 300-ms bandpassed noise centered on 1.0 kHz. The independent variable was the duration of the leading element, and the dependent variable was the smallest detectable gap between the elements. When the leading element was short in duration (5-10 ms), gap thresholds were close to 30 ms, which is close to the voice onset time that parses some voiced from unvoiced stop consonants. In experiment 4, the generality of the leading-element duration effect in between-channel gap detection was examined. Spectrally identical noises defining the leading and trailing edges of the gap were presented to the same or to

  1. Limits of 2D-TCA in detecting BOLD responses to epileptic activity.

    Science.gov (United States)

    Khatamian, Yasha Borna; Fahoum, Firas; Gotman, Jean

    2011-05-01

    Two-dimensional temporal clustering analysis (2D-TCA) is a relatively new functional MRI (fMRI) based technique that breaks blood oxygen level dependent activity into separate components based on timing and has shown potential for localizing epileptic activity independently of electroencephalography (EEG). 2D-TCA has only been applied to detect epileptic activity in a few studies and its limits in detecting activity of various forms (i.e. activation size, amplitude, and frequency) have not been investigated. This study evaluated 2D-TCA's ability to detect various forms of both simulated epileptic activity and EEG-fMRI activity detected in patients. When applied to simulated data, 2D-TCA consistently detected activity in 6min runs containing 5 spikes/run, 10 spikes/run, and one 5s long event with hemodynamic response function amplitudes of at least 1.5%, 1.25%, and 1% above baseline respectively. When applied to patient data, while detection of interictal spikes was inconsistent, 2D-TCA consistently produced results similar to those obtained by EEG-fMRI when at least 2 prolonged interictal events (a few seconds each) occurred during the run. However, even for such cases it was determined that 2D-TCA can only be used to validate localization by other means or to create hypotheses as to where activity may occur, as it also detects changes not caused by epileptic activity. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Detection of phosphatase activity in aquatic and terrestrial cyanobacterial strains

    Directory of Open Access Journals (Sweden)

    Babić Olivera B.

    2013-01-01

    Full Text Available Cyanobacteria, as highly adaptable microorganisms, are characterized by an ability to survive in different environmental conditions, in which a significant role belongs to their enzymes. Phosphatases are enzymes produced by algae in relatively large quantities in response to a low orthophosphate concentration and their activity is significantly correlated with their primary production. The activity of these enzymes was investigated in 11 cyanobacterial strains in order to determine enzyme synthesis depending on taxonomic and ecological group of cyanobacteria. The study was conducted with 4 terrestrial cyanobacterial strains, which belong to Nostoc and Anabaena genera, and 7 filamentous water cyanobacteria of Nostoc, Oscillatoria, Phormidium and Microcystis genera. The obtained results showed that the activity of acid and alkaline phosphatases strongly depended on cyanobacterial strain and the environment from which the strain originated. Higher activity of alkaline phosphatases, ranging from 3.64 to 85.14 μmolpNP/s/dm3, was recorded in terrestrial strains compared to the studied water strains (1.11-5.96 μmolpNP/s/dm3. The activity of acid phosphatases was higher in most tested water strains (1.67-6.28 μmolpNP/s/dm3 compared to the activity of alkaline phosphatases (1.11-5.96 μmolpNP/s/dm3. Comparing enzyme activity of nitrogen fixing and non-nitrogen fixing cyanobacteria, it was found that most nitrogen fixing strains had a higher activity of alkaline phosphatases. The data obtained in this work indicate that activity of phosphatases is a strain specific property. The results further suggest that synthesis and activity of phosphatases depended on eco-physiological characteristics of the examined cyanobacterial strains. This can be of great importance for the further study of enzymes and mechanisms of their activity as a part of cyanobacterial survival strategy in environments with extreme conditions. [Projekat Ministarstva nauke Republike

  3. A novel framework for intelligent surveillance system based on abnormal human activity detection in academic environments.

    Science.gov (United States)

    Al-Nawashi, Malek; Al-Hazaimeh, Obaida M; Saraee, Mohamad

    2017-01-01

    Abnormal activity detection plays a crucial role in surveillance applications, and a surveillance system that can perform robustly in an academic environment has become an urgent need. In this paper, we propose a novel framework for an automatic real-time video-based surveillance system which can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment. To develop our system, we have divided the work into three phases: preprocessing phase, abnormal human activity detection phase, and content-based image retrieval phase. For motion object detection, we used the temporal-differencing algorithm and then located the motions region using the Gaussian function. Furthermore, the shape model based on OMEGA equation was used as a filter for the detected objects (i.e., human and non-human). For object activities analysis, we evaluated and analyzed the human activities of the detected objects. We classified the human activities into two groups: normal activities and abnormal activities based on the support vector machine. The machine then provides an automatic warning in case of abnormal human activities. It also embeds a method to retrieve the detected object from the database for object recognition and identification using content-based image retrieval. Finally, a software-based simulation using MATLAB was performed and the results of the conducted experiments showed an excellent surveillance system that can simultaneously perform the tracking, semantic scene learning, and abnormality detection in an academic environment with no human intervention.

  4. Voice Activity Detection. Fundamentals and Speech Recognition System Robustness

    OpenAIRE

    Ramirez, J.; Gorriz, J. M.; Segura, J. C.

    2007-01-01

    This chapter has shown an overview of the main challenges in robust speech detection and a review of the state of the art and applications. VADs are frequently used in a number of applications including speech coding, speech enhancement and speech recognition. A precise VAD extracts a set of discriminative speech features from the noisy speech and formulates the decision in terms of well defined rule. The chapter has summarized three robust VAD methods that yield high speech/non-speech discri...

  5. Passive radiation detection using optically active CMOS sensors

    Science.gov (United States)

    Dosiek, Luke; Schalk, Patrick D.

    2013-05-01

    Recently, there have been a number of small-scale and hobbyist successes in employing commodity CMOS-based camera sensors for radiation detection. For example, several smartphone applications initially developed for use in areas near the Fukushima nuclear disaster are capable of detecting radiation using a cell phone camera, provided opaque tape is placed over the lens. In all current useful implementations, it is required that the sensor not be exposed to visible light. We seek to build a system that does not have this restriction. While building such a system would require sophisticated signal processing, it would nevertheless provide great benefits. In addition to fulfilling their primary function of image capture, cameras would also be able to detect unknown radiation sources even when the danger is considered to be low or non-existent. By experimentally profiling the image artifacts generated by gamma ray and β particle impacts, algorithms are developed to identify the unique features of radiation exposure, while discarding optical interaction and thermal noise effects. Preliminary results focus on achieving this goal in a laboratory setting, without regard to integration time or computational complexity. However, future work will seek to address these additional issues.

  6. The limits for detection of activated caspases of spermatozoa by western blot in human semen.

    Science.gov (United States)

    Brugnon, F; Pons-Rejraji, H; Artonne, C; Janny, L; Grizard, G

    2012-08-01

    Detection of activated caspases of spermatozoa could be helpful to evaluate male infertility. Although western blot is validated as a highly specific method to detect the proteins extracted from cells, the ability of this technique to detect activated sperm caspases in human semen may be limited. Indeed, round cells, which potentially contain some activated caspases, may be present in semen and interfere with the detection of activated sperm caspases. Moreover, it is necessary to evaluate the minimum amount of spermatozoa necessary to optimise the detection of activated caspases in semen samples. Our results showed that interference due to round cells contained in semen with activated caspase-3 requires separation of spermatozoa by density migration. This sperm preparation selects a mature sperm population that does not reflect the whole sperm population, and in infertile men with oligoasthenoteratozoospermia, the amount of spermatozoa thus selected is usually low. Moreover, the western blot technique's low detection sensitivity and the low level of caspase enzyme activity in human spermatozoa for activated caspase-3, -8 and -9 mean that large quantities of spermatozoa are needed to detect the expression of the activated caspases. These limitations prevent this method being used for routine analysis in clinical practice. © 2012 Blackwell Verlag GmbH.

  7. Evaluation of harmonic detection methods for active power filter applications

    DEFF Research Database (Denmark)

    Asiminoaei, Lucian; Blaabjerg, Frede; Hansen, Steffan

    2005-01-01

    In the attempt to minimize the harmonic disturbances created by the non-linear loads the choice of the active power filters comes out to improve the filtering efficiency and to solve many issues existing with classical passive filters. One of the key points for a proper implementation of an active...... implementation issues. The conclusions are collected and a comparison is given at the end, which is useful in deciding the future hardware setup implementation. The comparison shows that the choice of numerical filtering is a key factor for obtaining good accuracies and dynamics for an active filter....

  8. Contextual Multi-Scale Region Convolutional 3D Network for Activity Detection

    KAUST Repository

    Bai, Yancheng

    2018-01-28

    Activity detection is a fundamental problem in computer vision. Detecting activities of different temporal scales is particularly challenging. In this paper, we propose the contextual multi-scale region convolutional 3D network (CMS-RC3D) for activity detection. To deal with the inherent temporal scale variability of activity instances, the temporal feature pyramid is used to represent activities of different temporal scales. On each level of the temporal feature pyramid, an activity proposal detector and an activity classifier are learned to detect activities of specific temporal scales. Temporal contextual information is fused into activity classifiers for better recognition. More importantly, the entire model at all levels can be trained end-to-end. Our CMS-RC3D detector can deal with activities at all temporal scale ranges with only a single pass through the backbone network. We test our detector on two public activity detection benchmarks, THUMOS14 and ActivityNet. Extensive experiments show that the proposed CMS-RC3D detector outperforms state-of-the-art methods on THUMOS14 by a substantial margin and achieves comparable results on ActivityNet despite using a shallow feature extractor.

  9. Flow system for optical activity detection of vegetable extracts employing molecular exclusion continuous chromatographic detection

    Science.gov (United States)

    Fajer, V.; Rodríguez, C.; Naranjo, S.; Mesa, G.; Mora, W.; Arista, E.; Cepero, T.; Fernández, H.

    2006-02-01

    The combination of molecular exclusion chromatography and laser polarimetric detection has turned into a carbohydrate separation and quantification system for plant fluids of industrial value, making it possible the evaluation of the quality of sugarcane juices, agave juices and many other plant extracts. Some previous papers described a system where liquid chromatography separation and polarimetric detection using a LASERPOL 101M polarimeter with He-Ne light source allowed the collection and quantification of discrete samples for analytical purposes. In this paper, the authors are introducing a new improved system which accomplishes polarimetric measurements in a continuous flux. Chromatograms of several carbohydrates standard solutions were obtained as useful references to study juice quality of several sugarcane varieties under different physiological conditions. Results by either discrete or continuous flux systems were compared in order to test the validation of the new system. An application of the system to the diagnostics of scalded foliar is described. A computer program allowing the output of the chromatograms to a display on line and the possibility of digital storing, maxima detections, zone integration, and some other possibilities make this system very competitive and self-convincing.

  10. Minimum Detectable Activity in gamma spectrometry and its use in low level activity measurements

    International Nuclear Information System (INIS)

    Done, L.; Ioan, M-R.

    2016-01-01

    In this paper there are described three different algorithms of Minimum Detectable Activity (MDA) calculus, and its use in high resolution gamma spectrometry. In the first part, few introductive theoretical aspects related to the MDA are presented. Further, the theory was applied to real gamma rays spectrometry measurements and the results were compared with the activities reference values. Two different gamma spectrometry systems, both of them using High Purity Germanium (HPGe) detectors, but having different efficiencies, were used. Samples having different geometries and radionuclides content were measured. The measured samples were made by dissolving of some acids containing anthropogenic radionuclides in water, obtaining a density of 1 g/cm 3 . Choosing this type of matrix was done because of its high homogeneity. - Highlights: • Three different MDA algorithms were applied to gamma spectrometry measurements. • The measurements were performed using two HPGe detectors. • MDA performances of the two spectrometric systems were compared. • The measured samples had different geometries and contained a mixture of radionuclides. • MDA was studied also as a function of measuring time.

  11. Desulfurization Activated Phosphorothioate DNAzyme for the Detection of Thallium.

    Science.gov (United States)

    Huang, Po-Jung Jimmy; Vazin, Mahsa; Liu, Juewen

    2015-10-20

    Thallium (Tl) is a highly toxic heavy metal situated between mercury and lead in the periodic table. While its neighbors have been thoroughly studied for DNA-based sensing, little is known about thallium detection. In this work, in vitro selection of RNA-cleaving DNAzymes is carried out using Tl(3+) as the target metal cofactor. Both normal DNA and phosphorothioate (PS)-modified DNA are tested for this purpose. While no Tl(3+)-dependent DNAzymes are obtained, a DNA oligonucleotide containing a single PS-modified RNA nucleotide is found to cleave by ∼7% by Tl(3+) at the RNA position. The remaining 93% are desulfurized. By hybridization of this PS-modified oligonucleotide with the Tm7 DNAzyme, the cleavage yield increases to ∼40% in the presence of Tl(3+) and Er(3+). Tm7 is an Er(3+)-dependent RNA-cleaving DNAzyme. It cleaves only the normal substrate but is completely inactive using the PS-modified substrate. Tl(3+) desulfurizes the PS substrate to the normal substrate to be cleaved by Tm7 and Er(3+). This system is engineered into a catalytic beacon for Tl(3+) with a detection limit of 1.5 nM, which is below its maximal contamination limit defined by the U.S. Environmental Protection Agency (10 nM).

  12. Evaluation of harmonic detection methods for active power filter applications

    DEFF Research Database (Denmark)

    Asiminoaei, Lucian; Blaabjerg, Frede; Hansen, Steffan

    2005-01-01

    In the attempt to minimize the harmonic disturbances created by the non-linear loads the choice of the active power filters comes out to improve the filtering efficiency and to solve many issues existing with classical passive filters. One of the key points for a proper implementation of an active...... filter is to use a good method for current/voltage reference generation. There exist many implementations supported by different theories (either in time- or frequency-domain), which continuously debate their performances proposing ever better solutions. This paper gives a survey of the common used...... theories. Then, the work here proposes a simulation setup that decouples the harmonic reference generator from the active filter model and its controller. In this way the selected methods can be equally analyzed and compared with respect to their performance, which helps anticipating possible...

  13. Detection of aldehyde dehydrogenase activity in human corneal extracts

    NARCIS (Netherlands)

    Gondhowiardjo, T. D.; van Haeringen, N. J.; Hoekzema, R.; Pels, L.; Kijlstra, A.

    1991-01-01

    The major soluble protein in bovine corneal epithelial extracts is a 54 kD protein (BCP 54) which has recently been identified as the corneal aldehyde dehydrogenase. Although ALDH activity has been reported in human corneal extracts it was not yet clear whether this was identical with the 54 kD

  14. Pitfalls using tributyrin agar screening to detect lipolytic activity in ...

    African Journals Online (AJOL)

    The metagenomics approach is an efficient method for obtaining novel biocatalysts and useful genes from uncultured microorganisms within diverse environments. In this study, we constructed a metagenomic library using a South African deep mine biofilm sample. The library was screened for lipolytic activity using LB ...

  15. SPR imaging combined with cyclic voltammetry for the detection of neural activity

    Directory of Open Access Journals (Sweden)

    Hui Li

    2014-03-01

    Full Text Available Surface plasmon resonance (SPR detects changes in refractive index at a metal-dielectric interface. In this study, SPR imaging (SPRi combined with cyclic voltammetry (CV was applied to detect neural activity in isolated bullfrog sciatic nerves. The neural activities induced by chemical and electrical stimulation led to an SPR response, and the activities were recorded in real time. The activities of different parts of the sciatic nerve were recorded and compared. The results demonstrated that SPR imaging combined with CV is a powerful tool for the investigation of neural activity.

  16. Analysis of individual brain activation maps using hierarchical description and multiscale detection

    International Nuclear Information System (INIS)

    Poline, J.B.; Mazoyer, B.M.

    1994-01-01

    The authors propose a new method for the analysis of brain activation images that aims at detecting activated volumes rather than pixels. The method is based on Poisson process modeling, hierarchical description, and multiscale detection (MSD). Its performances have been assessed using both Monte Carlo simulated images and experimental PET brain activation data. As compared to other methods, the MSD approach shows enhanced sensitivity with a controlled overall type I error, and has the ability to provide an estimate of the spatial limits of the detected signals. It is applicable to any kind of difference image for which the spatial autocorrelation function can be approximated by a stationary Gaussian function

  17. Kohonen Neural Network Stress Detection Using Only Electrodermal Activity Features

    Directory of Open Access Journals (Sweden)

    BORNOIU, I.-V.

    2014-08-01

    Full Text Available This paper presents a method for identifying human stress levels by using a Kohonen neural network. The study focuses on differentiating between a relaxed and a stressed state and it presents a series of parameters (skin conductance response signal power, skin conductance response signal frequency, skin conductance level gradient, response rise time and response amplitude extracted only from the electrodermal activity signal. A very strict recording protocol was used to minimize the artifacts caused by the bad connection between electrodes and skin. A stress inducing method is presented that can be used to replicate results in laboratory conditions.

  18. Direct detection of relic active and sterile neutrinos

    Science.gov (United States)

    Li, Yu-Feng

    2016-05-01

    Both active and sterile sub-eV neutrinos can form the cosmic neutrino background in the early Universe. We consider the beta-decaying (e.g., 3H) and EC-decaying (e.g., 163Ho) nuclei as the promising targets to capture relic neutrinos in the laboratory. We calculate the capture rates of relic electron neutrinos and antineutrinos against the corresponding beta decay or electron capture (EC) decay backgrounds in the (3+Ns) flavor mixing scheme, and discuss the future prospect in terms of the PTOLEMY project. We stress that such direct measurements of hot DM might not be hopeless in the long term.

  19. BRAD: Software for BRain Activity Detection from hemodynamic response

    Czech Academy of Sciences Publication Activity Database

    Pidnebesna, Anna; Tomeček, David; Hlinka, Jaroslav

    2018-01-01

    Roč. 156, March (2018), s. 113-119 ISSN 0169-2607 R&D Projects: GA ČR GA13-23940S; GA ČR GA17-01251S; GA ČR GA13-23940S Grant - others:GA MŠk(CZ) LO1611 Institutional support: RVO:67985807 Keywords : deconvolution methods * functional magnetic resonance imaging * hemodynamic response * neuronal activity estimation * Wiener filtering Subject RIV: JC - Computer Hardware ; Software Impact factor: 2.503, year: 2016

  20. Active-Varying Sampling-Based Fault Detection Filter Design for Networked Control Systems

    Directory of Open Access Journals (Sweden)

    Yu-Long Wang

    2014-01-01

    Full Text Available This paper is concerned with fault detection filter design for continuous-time networked control systems considering packet dropouts and network-induced delays. The active-varying sampling period method is introduced to establish a new discretized model for the considered networked control systems. The mutually exclusive distribution characteristic of packet dropouts and network-induced delays is made full use of to derive less conservative fault detection filter design criteria. Compared with the fault detection filter design adopting a constant sampling period, the proposed active-varying sampling-based fault detection filter design can improve the sensitivity of the residual signal to faults and shorten the needed time for fault detection. The simulation results illustrate the merits and effectiveness of the proposed fault detection filter design.

  1. Artifact detection in electrodermal activity using sparse recovery

    Science.gov (United States)

    Kelsey, Malia; Palumbo, Richard Vincent; Urbaneja, Alberto; Akcakaya, Murat; Huang, Jeannie; Kleckner, Ian R.; Barrett, Lisa Feldman; Quigley, Karen S.; Sejdic, Ervin; Goodwin, Matthew S.

    2017-05-01

    Electrodermal Activity (EDA) - a peripheral index of sympathetic nervous system activity - is a primary measure used in psychophysiology. EDA is widely accepted as an indicator of physiological arousal, and it has been shown to reveal when psychologically novel events occur. Traditionally, EDA data is collected in controlled laboratory experiments. However, recent developments in wireless biosensing have led to an increase in out-of-lab studies. This transition to ambulatory data collection has introduced challenges. In particular, artifacts such as wearer motion, changes in temperature, and electrical interference can be misidentified as true EDA responses. The inability to distinguish artifact from signal hinders analyses of ambulatory EDA data. Though manual procedures for identifying and removing EDA artifacts exist, they are time consuming - which is problematic for the types of longitudinal data sets represented in modern ambulatory studies. This manuscript presents a novel technique to automatically identify and remove artifacts in EDA data using curve fitting and sparse recovery methods. Our method was evaluated using labeled data to determine the accuracy of artifact identification. Procedures, results, conclusions, and future directions are presented.

  2. Detecting exoplanets: jointly modeling radial velocity and stellar activity time series

    Science.gov (United States)

    Jones, David Edward; Stenning, David; Ford, Eric B.; Wolpert, Robert L.; Loredo, Thomas J.

    2017-06-01

    The radial velocity method is one of the most successful techniques for detecting exoplanets, but stellar activity often corrupts the radial velocity signal. This corruption can make it difficult to detect low mass planets and planets orbiting more active stars. A principled approach to recovering planet radial velocity signals in the presence of stellar activity was proposed by Rajpaul et al. (2015) and involves the use of dependent Gaussian processes to jointly model the corrupted radial velocity signal and multiple proxies for stellar activity. We build on this work in two ways: (i) we propose using dimension reduction techniques to construct more informative stellar activity proxies; (ii) we extend the Rajpaul et al. (2015) model to a larger class of models and use a model comparison procedure to select the best model for the particular stellar activity proxies at hand. Our framework enables us to compare the performance of various proxies in terms of the resulting statistical power for planet detection.

  3. On-line monitoring of nitrogenase activity in cyanobacteria by sensitive laser photoacoustic detection of ethylene

    NARCIS (Netherlands)

    Zuckermann, H.; Staal, M.J.; Stal, L.J.; Reuss, J.; te Lintel Hekkert, S.; Harren, F.J.M.; Parker, D.H.

    1997-01-01

    A new and extremely sensitive method for measuring nitrogenase activity through acetylene reduction is presented. Ethylene produced by nitrogenase-mediated reduction of acetylene is detected by using laser photoacoustics (LPA). This method possesses a detection limit making it 3 orders of magnitude

  4. Thermal neutron detection by activation of CaSO4:Dy + KBr thermoluminescent phosphors

    International Nuclear Information System (INIS)

    Gordon, A.M.P.L.; Muccillo, R.

    1979-01-01

    Thermoluminescence (TL) studies to detect thermal neutrons were performed in cold-pressed CaSO 4 :0,1%Dy + KBr samples. The detection is based on the self-irradiation of the CaSO 4 :Dy TL phosphor by the Br isotopes activated by exposure to a mixed neutron-gamma field. (Author) [pt

  5. Detection of botulinum toxin types A, B, E, and F activity using the quail embryo

    Science.gov (United States)

    We recently demonstrated an effective new model for the detection of botulinum toxin type A using quail embryos in place of the mouse model. These experiments demonstrated that the Japanese quail embryo at 15 days of incubation was an effective vertebrate animal model to detect the activity of botu...

  6. Using an active contour method to detect bilge dumps from SAR imagery

    CSIR Research Space (South Africa)

    Mdakane, Lizwe W

    2016-07-01

    Full Text Available Conference on Geoscience and Remote Sensing Symposium (IGARSS), 10-15 July, Beijing, China Using an active contour method to detect bilge dumps from SAR imagery L.W. Mdakane W. Kleynhans C.P. Schwegmann Abstract: An automatic approach to detect...

  7. Innate Reverse Transcriptase Activity of DNA Polymerase for Isothermal RNA Direct Detection.

    Science.gov (United States)

    Shi, Chao; Shen, Xiaotong; Niu, Shuyan; Ma, Cuiping

    2015-11-04

    RNA detection has become one of the most robust parts in molecular biology, medical diagnostics and drug discovery. Conventional RNA detection methods involve an extra reverse transcription step, which limits their further application for RNA rapid detection. We herein report a novel finding that Bst and Klenow DNA polymerases possess innate reverse transcriptase activities, so that the reverse transcription step and next amplification reaction can be combined to one step in isothermal RNA detection. We have demonstrated that Bst and Klenow DNA polymerases could be successfully used to reverse transcribe RNA within 125-nt length by real time RT-PCR and polyacrylamide gel electrophoresis (PAGE). Our findings will spur the development of a myriad of simple and easy to use RNA detection technologies for isothermal RNA direct detection. This will just meet the future needs of bioanalysis and clinical diagnosis to RNA rapid detection in POC settings and inspection and quarantine.

  8. LBA-ECO LC-35 GOES Imager Active Fire Detection Data, South America: 2000-2005

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is an active fire detection product resulting from the application of The Wildfire Automated Biomass Burning Algorithm (WF_ABBA) to Geostationary...

  9. LBA-ECO LC-35 GOES Imager Active Fire Detection Data, South America: 2000-2005

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set is an active fire detection product resulting from the application of The Wildfire Automated Biomass Burning Algorithm (WF_ABBA) to...

  10. On the use of physical activity monitoring for estrus detection in dairy cows

    DEFF Research Database (Denmark)

    Løvendahl, P; Chagunda, M

    2010-01-01

    Detection of estrus in dairy cattle is effectively aided by electronic activity tags or pedometers. Characterization of estrus intensity and duration is also possible from activity data. This study aimed to develop an algorithm to detect and characterize behavioral estrus from hourly recorded...... episodes. The algorithm was based on deviations from exponentially smoothed hourly activity counts and was used to identify onset, duration, and intensity of estrus. Learning data included 461 successful inseminations with activity records over a 2-wk period before and after the artificial insemination...

  11. A CMOS Active Pixel Sensor for Charged Particle Detection

    Energy Technology Data Exchange (ETDEWEB)

    Matis, Howard S.; Bieser, Fred; Kleinfelder, Stuart; Rai, Gulshan; Retiere, Fabrice; Ritter, Hans George; Singh, Kunal; Wurzel, Samuel E.; Wieman, Howard; Yamamoto, Eugene

    2002-12-02

    Active Pixel Sensor (APS) technology has shown promise for next-generation vertex detectors. This paper discusses the design and testing of two generations of APS chips. Both are arrays of 128 by 128 pixels, each 20 by 20 {micro}m. Each array is divided into sub-arrays in which different sensor structures (4 in the first version and 16 in the second) and/or readout circuits are employed. Measurements of several of these structures under Fe{sup 55} exposure are reported. The sensors have also been irradiated by 55 MeV protons to test for radiation damage. The radiation increased the noise and reduced the signal. The noise can be explained by shot noise from the increased leakage current and the reduction in signal is due to charge being trapped in the epi layer. Nevertheless, the radiation effect is small for the expected exposures at RHIC and RHIC II. Finally, we describe our concept for mechanically supporting a thin silicon wafer in an actual detector.

  12. Bone Scan in Detection of Biological Activity in Nonhypertrophic Fracture Nonunion

    OpenAIRE

    Gandhi, Sunny J.; Rabadiya, Bhavdeep

    2017-01-01

    Biological activity of the fracture site is very important factor in treatment planning of fracture nonunion. If no biological activity is detected, then an autologous bone graft can be supplemented or osteogenic supplementations, such as bone morphogenetic protein is given. If biological activity is present, then secure fixation is sufficient to achieve bony union. Biological activity of nonunions is usually assessed by conventional radiographs. The presence of callus formation is usually as...

  13. Topoisomerase I as a Biomarker: Detection of Activity at the Single Molecule Level

    DEFF Research Database (Denmark)

    Proszek, Joanna; Roy, Amit; Jakobsen, Ann-Katrine

    2014-01-01

    of hTopI cleavage-religation activity at the single molecule level, may be used to detect posttranslational enzymatic differences influencing CPT response. These differences cannot be detected by analysis of hTopI gene copy number, mRNA amount, or protein amount, and only become apparent upon measuring......Human topoisomerase I (hTopI) is an essential cellular enzyme. The enzyme is often upregulated in cancer cells, and it is a target for chemotherapeutic drugs of the camptothecin (CPT) family. Response to CPT-based treatment is dependent on hTopI activity, and reduction in activity, and mutations...... in hTopI have been reported to result in CPT resistance. Therefore, hTOPI gene copy number, mRNA level, protein amount, and enzyme activity have been studied to explain differences in cellular response to CPT. We show that Rolling Circle Enhanced Enzyme Activity Detection (REEAD), allowing measurement...

  14. Micro Surface Defect Detection Method for Silicon Steel Strip Based on Saliency Convex Active Contour Model

    Directory of Open Access Journals (Sweden)

    Kechen Song

    2013-01-01

    Full Text Available Accurate detection of surface defect is an indispensable section in steel surface inspection system. In order to detect the micro surface defect of silicon steel strip, a new detection method based on saliency convex active contour model is proposed. In the proposed method, visual saliency extraction is employed to suppress the clutter background for the purpose of highlighting the potential objects. The extracted saliency map is then exploited as a feature, which is fused into a convex energy minimization function of local-based active contour. Meanwhile, a numerical minimization algorithm is introduced to separate the micro surface defects from cluttered background. Experimental results demonstrate that the proposed method presents good performance for detecting micro surface defects including spot-defect and steel-pit-defect. Even in the cluttered background, the proposed method detects almost all of the microdefects without any false objects.

  15. FAST POWER LINE DETECTION AND LOCALIZATION USING STEERABLE FILTER FOR ACTIVE UAV GUIDANCE

    Directory of Open Access Journals (Sweden)

    Y. Liu

    2012-08-01

    Full Text Available In this paper we present a fast power line detection and localisation algorithm as well as propose a high-level guidance architecture for active vision-based Unmanned Aerial Vehicle (UAV guidance. The detection stage is based on steerable filters for edge ridge detection, followed by a line fitting algorithm to refine candidate power lines in images. The guidance architecture assumes an UAV with an onboard Gimbal camera. We first control the position of the Gimbal such that the power line is in the field of view of the camera. Then its pose is used to generate the appropriate control commands such that the aircraft moves and flies above the lines. We present initial experimental results for the detection stage which shows that the proposed algorithm outperforms two state-of-the-art line detection algorithms for power line detection from aerial imagery.

  16. The development and characterization of an ELISA specifically detecting the active form of cathepsin K

    DEFF Research Database (Denmark)

    Sun, S; Karsdal, M A; Bay-Jensen, A C

    2013-01-01

    , such as osteoporosis or ankylosing spondylitis. METHODS: Presently there are no robust assays for the assessment of active cathepsin K in serum, and therefore an ELISA specifically detecting the N-terminal of the active form of cathepsin K was developed. RESULTS: The assay was technically robust, with a lowest limit...

  17. Contribution of spiking activity in the primary auditory cortex to detection in noise.

    Science.gov (United States)

    Christison-Lagay, Kate L; Bennur, Sharath; Cohen, Yale E

    2017-12-01

    A fundamental problem in hearing is detecting a "target" stimulus (e.g., a friend's voice) that is presented with a noisy background (e.g., the din of a crowded restaurant). Despite its importance to hearing, a relationship between spiking activity and behavioral performance during such a "detection-in-noise" task has yet to be fully elucidated. In this study, we recorded spiking activity in primary auditory cortex (A1) while rhesus monkeys detected a target stimulus that was presented with a noise background. Although some neurons were modulated, the response of the typical A1 neuron was not modulated by the stimulus- and task-related parameters of our task. In contrast, we found more robust representations of these parameters in population-level activity: small populations of neurons matched the monkeys' behavioral sensitivity. Overall, these findings are consistent with the hypothesis that the sensory evidence, which is needed to solve such detection-in-noise tasks, is represented in population-level A1 activity and may be available to be read out by downstream neurons that are involved in mediating this task. NEW & NOTEWORTHY This study examines the contribution of A1 to detecting a sound that is presented with a noisy background. We found that population-level A1 activity, but not single neurons, could provide the evidence needed to make this perceptual decision. Copyright © 2017 the American Physiological Society.

  18. Detection of CHH/GIH activity in fractionated extracts from the eyestalk of Banana prawn

    Directory of Open Access Journals (Sweden)

    Wilaiwan Chotigeat

    2005-12-01

    Full Text Available Sinus gland from Penaeus merguiensis De man, 1888 was extracted and proteins were fractionated on a HPLC column (μBondapack-phenyl column, 9 mm i.d., 10 μm particle size, Waters. Three major peaks (peaks 3, 5 and 6 were collected and investigated for crustacean hyperglycemic hormone (CHH and gonad inhibiting hormone activity (GIH. The CHH activity of the peak 5 fraction was significantly higher than the control while peak 6 did not have significant CHH activity. No CHH activity was found in the peak 3 fraction. GIH activity was determined by inhibition of total protein and vitellin synthesis in ovarian tissue. An antivitellin antibody was prepared and used for immunoprecipitation in the GIH activity assay. Hence GIH activity was detected in peaks 5 and 6 while peak 3 had gonad stimulating hormone like activity (GSH-like activity.

  19. Analytical activity of the laboratory for detection of irradiated food in 2005

    International Nuclear Information System (INIS)

    Stachowicz, W.; Malec-Czechowska, K.; Lehner, K.; Guzik, G.P.; Laubsztejn, M.

    2006-01-01

    In the paper activity of the Laboratory for Detection of Irradiated Foods, Institute of Nuclear Chemistry and Technology in 2005 is presented. In the presented period two new detection methods have been implemented: one is based on EPR (electron paramagnetic resonance) spectrometry, while the other employs photostimulated luminescence released from a sample proving its radiation treatment. Statistics of the analyzed sample types and and the analytical methods applied is presented

  20. Proof of Principle for Active Detection of Fissionable Material Using Intense, Pulsed-Bremsstrahlung-Induced Photofission

    Science.gov (United States)

    2014-10-07

    reasonable approximation, is presently being investigated using neutron detection data taken from a Van de Graaff accelerator. The large event-number...bremsstrahlung from the Naval Research Laboratory Mercury pulsed-power generator (200-kA peak current, 50-ns pulse width) induces photofission in...single pulse is generally termed intense, pulsed, active detection (IPAD).15 The high-power electrical pulse is used to create a short (~ 100 ns

  1. Combination of activity and lying/standing data for detection of oestrus in cows

    DEFF Research Database (Denmark)

    Jónsson, Ragnar Ingi; Blanke, Mogens; Poulsen, Niels Kjølstad

    2009-01-01

    is measured by a sensor attached to the hind leg of the cow. Activity and lying/standing behaviour are modelled as a discrete event system, constructed using automata theory. In an attempt to estimate a biologically relevant lying balance, a lying balance indicator is constructed and is influencing transition...... and results of decision algorithms are presented for Oestrus detection. Detection based on the lying balance indicator and the two sets of measured information are demonstrated to increase the detection sensitivity to 100% for a set of 10 cows....

  2. Automatic seizure detection in SEEG using high frequency activities in wavelet domain.

    Science.gov (United States)

    Ayoubian, L; Lacoma, H; Gotman, J

    2013-03-01

    Existing automatic detection techniques show high sensitivity and moderate specificity, and detect seizures a relatively long time after onset. High frequency (80-500 Hz) activity has recently been shown to be prominent in the intracranial EEG of epileptic patients but has not been used in seizure detection. The purpose of this study is to investigate if these frequencies can contribute to seizure detection. The system was designed using 30 h of intracranial EEG, including 15 seizures in 15 patients. Wavelet decomposition, feature extraction, adaptive thresholding and artifact removal were employed in training data. An EMG removal algorithm was developed based on two features: Lack of correlation between frequency bands and energy-spread in frequency. Results based on the analysis of testing data (36 h of intracranial EEG, including 18 seizures) show a sensitivity of 72%, a false detection of 0.7/h and a median delay of 5.7 s. Missed seizures originated mainly from seizures with subtle or absent high frequencies or from EMG removal procedures. False detections were mainly due to weak EMG or interictal high frequency activities. The system performed sufficiently well to be considered for clinical use, despite the exclusive use of frequencies not usually considered in clinical interpretation. High frequencies have the potential to contribute significantly to the detection of epileptic seizures. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  3. INTERACTIVE CHANGE DETECTION USING HIGH RESOLUTION REMOTE SENSING IMAGES BASED ON ACTIVE LEARNING WITH GAUSSIAN PROCESSES

    Directory of Open Access Journals (Sweden)

    H. Ru

    2016-06-01

    Full Text Available Although there have been many studies for change detection, the effective and efficient use of high resolution remote sensing images is still a problem. Conventional supervised methods need lots of annotations to classify the land cover categories and detect their changes. Besides, the training set in supervised methods often has lots of redundant samples without any essential information. In this study, we present a method for interactive change detection using high resolution remote sensing images with active learning to overcome the shortages of existing remote sensing image change detection techniques. In our method, there is no annotation of actual land cover category at the beginning. First, we find a certain number of the most representative objects in unsupervised way. Then, we can detect the change areas from multi-temporal high resolution remote sensing images by active learning with Gaussian processes in an interactive way gradually until the detection results do not change notably. The artificial labelling can be reduced substantially, and a desirable detection result can be obtained in a few iterations. The experiments on Geo-Eye1 and WorldView2 remote sensing images demonstrate the effectiveness and efficiency of our proposed method.

  4. Detection and activity of iodine-131 in brown algae collected in the Japanese coastal areas.

    Science.gov (United States)

    Morita, Takami; Niwa, Kentaro; Fujimoto, Ken; Kasai, Hiromi; Yamada, Haruya; Nishiutch, Kou; Sakamoto, Tatsuya; Godo, Waichiro; Taino, Seiya; Hayashi, Yoshihiro; Takeno, Koji; Nishigaki, Tomokazu; Fujiwara, Kunihiro; Aratake, Hisamichi; Kamonoshita, Shingo; Hashimoto, Hiroshi; Kobayashi, Takuya; Otosaka, Sigeyoshi; Imanaka, Tetsuji

    2010-07-15

    Iodine-131 (physical half-life: 8.04 days) was detected in brown algae collected off the Japanese coast. Brown algae have been extensively used as bioindicators for radioiodine because of their ability to accumulate radionuclides in high concentration factors. The maximum measured specific activity of (131)I in brown algae was 0.37 + or - 0.010 Bq/kg-wet. Cesium-137 was also detected in all brown algal samples used in this study. There was no correlation between specific activities of (131)I and (137)Cs in these seaweeds. The specific activity of (137)Cs ranged from 0.0034 + or - 0.00075 to 0.090 + or - 0.014 Bq/kg-wet. Low specific activity and minimal variability of (137)Cs in brown algae indicated that past nuclear weapon tests were the source of (137)Cs. Although nuclear power stations and nuclear fuel reprocessing plants are known to be pollution sources of (131)I, there was no relationship between the sites where (131)I was detected and the locations of nuclear power facilities. Most of the sites where (131)I was detected were near big cities with large populations. Iodine-131 is frequently used in diagnostic and therapeutic nuclear medicine. On the basis of the results, we suggest that the likely pollution source of (131)I, detected in brown seaweeds, is not nuclear power facilities, but nuclear medicine procedures. Copyright 2010 Elsevier B.V. All rights reserved.

  5. Lingual lipase activity in the orosensory detection of fat by humans.

    Science.gov (United States)

    Kulkarni, Bhushan V; Mattes, Richard D

    2014-06-15

    Lingual lipase generates nonesterified fatty acids (NEFA) from dietary fats during oral processing by lipolysis. Lingual lipase in rodents has strong lipolytic activity and plays a critical role in oral detection of fats. The functional activity of lingual lipase during oral processing of high-fat foods in humans remains poorly characterized. Five commonly consumed high-fat foods varying in physical states and fatty acid composition (almond, almond butter, olive oil, walnut, and coconut) were masticated by 15 healthy human subjects at the rate of one chew per second with and without lipase inhibitor orlistat. Salivary NEFA concentrations were measured. To determine the role of lingual lipase in oral fat detection, sensory ratings were obtained from the same 15 human subjects for almond butter with and without orlistat. Lingual lipase was active during oral processing of almond and coconut. No activity of lingual lipase was detected during processing of almond butter. There was only weak evidence lingual lipase is a determinant of oral fat detection. Lingual lipase may only contribute to NEFA generation and oral fat detection of fatty foods that require stronger oral processing effort. Copyright © 2014 the American Physiological Society.

  6. Detection and activity of iodine-131 in brown algae collected in the Japanese coastal areas

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Takami, E-mail: takam@affrc.go.jp [Fisheries Research Agency, 15F Queen' s Tower B, Minato Mirai Nishi-ku, Yokohama, Kanagawa 220-6115 (Japan); Niwa, Kentaro; Fujimoto, Ken; Kasai, Hiromi; Yamada, Haruya; Nishiutch, Kou [Fisheries Research Agency, 15F Queen' s Tower B, Minato Mirai Nishi-ku, Yokohama, Kanagawa 220-6115 (Japan); Sakamoto, Tatsuya; Godo, Waichiro [Ushimado Marine Laboratory, Okayama University, 130-17, Kashino 130-17, Ushimado, Setouchi, Okayama 701-43 (Japan); Taino, Seiya; Hayashi, Yoshihiro [Kochi Prefectural Fisheries Experimental Station, Uranoutchhaigata 1153-23, Susaki, Kouch, 785-0167 Japan (Japan); Takeno, Koji; Nishigaki, Tomokazu; Fujiwara, Kunihiro [Kyoto Prefectural Agriculture, Forestry and Fisheries Technology Research Center, Odashukuno, Miyazu, Kyoto, 626-0052 Japan (Japan); Aratake, Hisamichi [Miyazaki Prefectural Fisheries Experimental Station, Aoshima 6-16-3, Miyazaki, Miyazaki 889-2162 Japan (Japan); Kamonoshita, Shingo [Ibaragi Prefectural Fisheries Experimental Station, Mitsuzuka3551-8, Hiraiso, Hitachnaka, Ibaragi, 311-1203 Japan (Japan); Hashimoto, Hiroshi [Fukui Prefectural Fisheries Experimental Station, Urasoko 23-1, Tsuruga, Fukui, 914-0843 Japan (Japan); Kobayashi, Takuya; Otosaka, Sigeyoshi [Japan Atomic Energy Agency, Shirakata Shirane 2-4, Tokai, Ibaraki, 319-1195 Japan (Japan); Imanaka, Tetsuji [Research Reactor Institute, Kyoto University, Kumatori-cho, Osaka, 590-0494 Japan (Japan)

    2010-07-15

    Iodine-131 (physical half-life: 8.04 days) was detected in brown algae collected off the Japanese coast. Brown algae have been extensively used as bioindicators for radioiodine because of their ability to accumulate radionuclides in high concentration factors. The maximum measured specific activity of {sup 131}I in brown algae was 0.37 {+-} 0.010 Bq/kg-wet. Cesium-137 was also detected in all brown algal samples used in this study. There was no correlation between specific activities of {sup 131}I and {sup 137}Cs in these seaweeds. The specific activity of {sup 137}Cs ranged from 0.0034 {+-} 0.00075 to 0.090 {+-} 0.014 Bq/kg-wet. Low specific activity and minimal variability of {sup 137}Cs in brown algae indicated that past nuclear weapon tests were the source of {sup 137}Cs. Although nuclear power stations and nuclear fuel reprocessing plants are known to be pollution sources of {sup 131}I, there was no relationship between the sites where {sup 131}I was detected and the locations of nuclear power facilities. Most of the sites where {sup 131}I was detected were near big cities with large populations. Iodine-131 is frequently used in diagnostic and therapeutic nuclear medicine. On the basis of the results, we suggest that the likely pollution source of {sup 131}I, detected in brown seaweeds, is not nuclear power facilities, but nuclear medicine procedures.

  7. Amplified and in situ detection of redox-active metabolite using a biobased redox capacitor.

    Science.gov (United States)

    Kim, Eunkyoung; Gordonov, Tanya; Bentley, William E; Payne, Gregory F

    2013-02-19

    Redox cycling provides a mechanism to amplify electrochemical signals for analyte detection. Previous studies have shown that diverse mediators/shuttles can engage in redox-cycling reactions with a biobased redox capacitor that is fabricated by grafting redox-active catechols onto a chitosan film. Here, we report that redox cycling with this catechol-chitosan redox capacitor can amplify electrochemical signals for detecting a redox-active bacterial metabolite. Specifically, we studied the redox-active bacterial metabolite pyocyanin that is reported to be a virulence factor and signaling molecule for the opportunistic pathogen P. aeruginosa. We demonstrate that redox cycling can amplify outputs from various electrochemical methods (cyclic voltammetry, chronocoulometry, and differential pulse voltammetry) and can lower the detection limit of pyocyanin to 50 nM. Further, the compatibility of this biobased redox capacitor allows the in situ monitoring of the production of redox-active metabolites (e.g., pyocyanin) during the course of P. aeruginosa cultivation. We anticipate that the amplified output of redox-active virulence factors should permit an earlier detection of life-threatening infections by the opportunistic pathogen P. aeruginosa while the "bio-compatibility" of this measurement approach should facilitate in situ study of the spatiotemporal dynamics of bacterial redox signaling.

  8. Highly Sensitive Detection of Minimal Cardiac Ischemia using Positron Emission Tomography Imaging of Activated Platelets

    Science.gov (United States)

    Ziegler, Melanie; Alt, Karen; Paterson, Brett M.; Kanellakis, Peter; Bobik, Alex; Donnelly, Paul S.; Hagemeyer, Christoph E.; Peter, Karlheinz

    2016-01-01

    A reliable method for the diagnosis of minimal cardiac ischemia would meet a strong demand for the sensitive diagnosis of coronary artery disease in cardiac stress testing and risk stratification in patients with chest pain but unremarkable ECGs and biomarkers. We hypothesized that platelets accumulate early on in ischemic myocardium and a newly developed technology of non-invasive molecular PET imaging of activated platelets can thus detect minimal degrees of myocardial ischemia. To induce different degrees of minimal cardiac ischemia, the left anterior descending artery (LAD) was ligated for 10, 20 or 60 min. Mice were injected with a newly generated scFvanti-GPIIb/IIIa-64CuMeCOSar radiotracer, composed of a single-chain antibody that only binds to activated integrin GPIIb/IIIa (αIIbβIII) and thus to activated platelets, and a sarcophagine cage MeCOSar complexing the long half-life PET tracer copper-64. A single PET/CT scan was performed. Evans Blue/TTC staining to detect necrosis as well as classical serological biomarkers like Troponin I and heart-type fatty acid-binding protein (H-FABP) were negative, whereas PET imaging of activated platelets was able to detect small degrees of ischemia. Taken together, molecular PET imaging of activated platelets represents a unique and highly sensitive method to detect minimal cardiac ischemia. PMID:27909290

  9. Combination of activity and lying/standing data for detection of oestrus in cows

    DEFF Research Database (Denmark)

    Jónsson, Ragnar Ingi; Blanke, Mogens; Poulsen, Niels Kjølstad

    2009-01-01

    is measured by a sensor attached to the hind leg of the cow. Activity and lying/standing behaviour are modelled as a discrete event system, constructed using automata theory. In an attempt to estimate a biologically relevant lying balance, a lying balance indicator is constructed and is influencing transition......The objective of this study is to develop an algorithm for detecting oestrus in dairy cows from measurements of activity and duration of lying/standing periods. Each cows activity is measured by a sensor attached to the neck that returns an activity index for each hour. Duration of lying...

  10. Testing the applicability of rapid on-site enzymatic activity detection for surface water monitoring

    Science.gov (United States)

    Stadler, Philipp; Vogl, Wolfgang; Juri, Koschelnik; Markus, Epp; Maximilian, Lackner; Markus, Oismüller; Monika, Kumpan; Peter, Strauss; Regina, Sommer; Gabriela, Ryzinska-Paier; Farnleitner Andreas, H.; Matthias, Zessner

    2015-04-01

    On-site detection of enzymatic activities has been suggested as a rapid surrogate for microbiological pollution monitoring of water resources (e.g. using glucuronidases, galactosidases, esterases). Due to the possible short measuring intervals enzymatic methods have high potential as near-real time water quality monitoring tools. This presentation describes results from a long termed field test. For twelve months, two ColiMinder devices (Vienna Water Monitoring, Austria) for on-site determination of enzymatic activity were tested for stream water monitoring at the experimental catchment HOAL (Hydrological Open Air Laboratory, Center for Water Resource Systems, Vienna University of Technology). The devices were overall able to follow and reflect the diverse hydrological and microbiological conditions of the monitored stream during the test period. Continuous data in high temporal resolution captured the course of enzymatic activity in stream water during diverse rainfall events. The method also proofed sensitive enough to determine diurnal fluctuations of enzymatic activity in stream water during dry periods. The method was able to capture a seasonal trend of enzymatic activity in stream water that matches the results gained from Colilert18 analysis for E. coli and coliform bacteria of monthly grab samples. Furthermore the comparison of ColiMinder data with measurements gained at the same test site with devices using the same method but having different construction design (BACTcontrol, microLAN) showed consistent measuring results. Comparative analysis showed significant differences between measured enzymatic activity (modified fishman units and pmol/min/100ml) and cultivation based analyses (most probable number, colony forming unit). Methods of enzymatic activity measures are capable to detect ideally the enzymatic activity caused by all active target bacteria members, including VBNC (viable but nonculturable) while cultivation based methods cannot detect VBNC

  11. Detection of Early Morning Daily Activities with Static Home and Wearable Wireless Sensors

    Directory of Open Access Journals (Sweden)

    David Vanderpool

    2007-10-01

    Full Text Available This paper describes a flexible, cost-effective, wireless in-home activity monitoring system for assisting patients with cognitive impairments due to traumatic brain injury (TBI. The system locates the subject with fixed home sensors and classifies early morning bathroom activities of daily living with a wearable wireless accelerometer. The system extracts time- and frequency-domain features from the accelerometer data and classifies these features with a hybrid classifier that combines Gaussian mixture models and a finite state machine. In particular, the paper establishes that despite similarities between early morning bathroom activities of daily living, it is possible to detect and classify these activities with high accuracy. It also discusses system training and provides data to show that with proper feature selection, accurate detection and classification are possible for any subject with no subject specific training.

  12. Fast Temporal Activity Proposals for Efficient Detection of Human Actions in Untrimmed Videos

    KAUST Repository

    Heilbron, Fabian Caba

    2016-12-13

    In many large-scale video analysis scenarios, one is interested in localizing and recognizing human activities that occur in short temporal intervals within long untrimmed videos. Current approaches for activity detection still struggle to handle large-scale video collections and the task remains relatively unexplored. This is in part due to the computational complexity of current action recognition approaches and the lack of a method that proposes fewer intervals in the video, where activity processing can be focused. In this paper, we introduce a proposal method that aims to recover temporal segments containing actions in untrimmed videos. Building on techniques for learning sparse dictionaries, we introduce a learning framework to represent and retrieve activity proposals. We demonstrate the capabilities of our method in not only producing high quality proposals but also in its efficiency. Finally, we show the positive impact our method has on recognition performance when it is used for action detection, while running at 10FPS.

  13. Genome-Wide Association Study Identifies Single Nucleotide Polymorphism in DYRK1A Associated with Replication of HIV-1 in Monocyte-Derived Macrophages

    NARCIS (Netherlands)

    Bol, Sebastiaan M.; Moerland, Perry D.; Limou, Sophie; van Remmerden, Yvonne; Coulonges, Cédric; van Manen, Daniëlle; Herbeck, Joshua T.; Fellay, Jacques; Sieberer, Margit; Sietzema, Jantine G.; van 't Slot, Ruben; Martinson, Jeremy; Zagury, Jean-François; Schuitemaker, Hanneke; van 't Wout, Angélique B.

    2011-01-01

    Background: HIV-1 infected macrophages play an important role in rendering resting T cells permissive for infection, in spreading HIV-1 to T cells, and in the pathogenesis of AIDS dementia. During highly active anti-retroviral treatment (HAART), macrophages keep producing virus because tissue

  14. Online Detection of Peroxidase Using 3D Printing, Active Magnetic Mixing, and Spectra Analysis

    Science.gov (United States)

    2017-01-01

    A new method for online detection of peroxidase (POD) using 3D printing, active magnetic mixing, fluidic control, and optical detection was developed and demonstrated in this study. The proposed POD detection system consisted of a 3D printing and active magnetic mixing based fluidic chip for online catalytic reaction, an optical detector with a fluidic flow cell for quantitative determination of the final catalysate, and a single-chip microcontroller based controller for automatic control of two rotating magnetic fields and four precise peristaltic pumps. Horseradish peroxidase (HRP) was used as research model and a linear relationship between the absorbance at the characteristic wavelength of 450 nm and the concentration of HRP of 1/4–1/128 μg mL−1 was obtained as A  =  0.257ln⁡(C) + 1.425 (R2  = 0.976). For the HRP spiked pork tests, the recoveries of HRP ranged from 93.5% to 110.4%, indicating that this proposed system was capable of detecting HRP in real samples. It has the potential to be extended for online detection of the activity of other enzymes and integration with ELISA method for biological and chemical analysis. PMID:28523275

  15. Rapid screening for Chlamydia trachomatis infection by detecting ?-mannosidase activity in urogenital tract specimens

    OpenAIRE

    Wang, Ze-yu; Fu, Guang-yu; Wang, Shan-mei; Qin, Dong-chun; Wang, Zhong-quan; Cui, Jing

    2013-01-01

    Abstract Background Chlamydia trachomatis may cause multiple different urogenital tract disorders, but current non-culture assays for rapid screening of C. trachomatis typically use immunochromatography-based methods. We established another new rapid non-culture method for detection of C. trachomatis based on the measurement of α-mannosidase enzymatic activity in urogenital tract specimens. Method To evaluate the performance of this method, α-mannosidase activities of C. trachomatis serotype ...

  16. Modeling of activation data in the BrainMapTM database: Detection of outliers

    DEFF Research Database (Denmark)

    Nielsen, Finn Årup; Hansen, Lars Kai

    2002-01-01

    We describe a system for meta-analytical modeling of activation foci from functional neuroimaging studies. Our main vehicle is a set of density models in Talairach space capturing the distribution of activation foci in sets of experiments labeled by lobar anatomy. One important use of such densit...... of atlases for outlier detection. Hum. Brain Mapping 15:146-156, 2002. © 2002 Wiley-Liss, Inc....

  17. Optimal Parameter Exploration for Online Change-Point Detection in Activity Monitoring Using Genetic Algorithms.

    Science.gov (United States)

    Khan, Naveed; McClean, Sally; Zhang, Shuai; Nugent, Chris

    2016-10-26

    In recent years, smart phones with inbuilt sensors have become popular devices to facilitate activity recognition. The sensors capture a large amount of data, containing meaningful events, in a short period of time. The change points in this data are used to specify transitions to distinct events and can be used in various scenarios such as identifying change in a patient's vital signs in the medical domain or requesting activity labels for generating real-world labeled activity datasets. Our work focuses on change-point detection to identify a transition from one activity to another. Within this paper, we extend our previous work on multivariate exponentially weighted moving average (MEWMA) algorithm by using a genetic algorithm (GA) to identify the optimal set of parameters for online change-point detection. The proposed technique finds the maximum accuracy and F_measure by optimizing the different parameters of the MEWMA, which subsequently identifies the exact location of the change point from an existing activity to a new one. Optimal parameter selection facilitates an algorithm to detect accurate change points and minimize false alarms. Results have been evaluated based on two real datasets of accelerometer data collected from a set of different activities from two users, with a high degree of accuracy from 99.4% to 99.8% and F_measure of up to 66.7%.

  18. Rolling circle amplification-based detection of human topoisomerase I activity on magnetic beads.

    Science.gov (United States)

    Zuccaro, Laura; Tesauro, Cinzia; Cerroni, Barbara; Ottaviani, Alessio; Knudsen, Birgitta Ruth; Balasubramanian, Kannan; Desideri, Alessandro

    2014-04-15

    A high-sensitivity assay has been developed for the detection of human topoisomerase I with single molecule resolution. The method uses magnetic sepharose beads to concentrate rolling circle products, produced by the amplification of DNA molecules circularized by topoisomerase I and detectable with a confocal microscope as single and discrete dots, once reacted with fluorescent probes. Each dot, corresponding to a single cleavage-religation event mediated by the enzyme, can be counted due to its high signal/noise ratio, allowing detection of 0.3pM enzyme and representing a valid method to detect the enzyme activity in highly diluted samples. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Active acoustic leak detection for LMFBR steam generator. Sound attenuation due to bubbles

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi; Sakuma, Toshio

    1995-01-01

    In the steam generators (SG) of LMFBR, it is necessary to detect the leakage of water from tubes of heat exchangers as soon as it occurs. The active acoustic detection method has drawn general interest owing to its short response time and reduction of the influence of background noise. In this paper, the application of the active acoustic detection method for SG is proposed, and sound attenuation by bubbles is investigated experimentally. Furthermore, using the SG sector model, sound field characteristics and sound attenuation characteristics due to injection of bubbles are studied. It is clarified that the sound attenuation depends upon bubble size as well as void fraction, that the distance attenuation of sound in the SG model containing heat transfer tubes is 6dB for each two-fold increase of distance, and that emitted sound attenuates immediately upon injection of bubbles. (author)

  20. Unsupervised Object Modeling and Segmentation with Symmetry Detection for Human Activity Recognition

    Directory of Open Access Journals (Sweden)

    Jui-Yuan Su

    2015-04-01

    Full Text Available In this paper we present a novel unsupervised approach to detecting and segmenting objects as well as their constituent symmetric parts in an image. Traditional unsupervised image segmentation is limited by two obvious deficiencies: the object detection accuracy degrades with the misaligned boundaries between the segmented regions and the target, and pre-learned models are required to group regions into meaningful objects. To tackle these difficulties, the proposed approach aims at incorporating the pair-wise detection of symmetric patches to achieve the goal of segmenting images into symmetric parts. The skeletons of these symmetric parts then provide estimates of the bounding boxes to locate the target objects. Finally, for each detected object, the graphcut-based segmentation algorithm is applied to find its contour. The proposed approach has significant advantages: no a priori object models are used, and multiple objects are detected. To verify the effectiveness of the approach based on the cues that a face part contains an oval shape and skin colors, human objects are extracted from among the detected objects. The detected human objects and their parts are finally tracked across video frames to capture the object part movements for learning the human activity models from video clips. Experimental results show that the proposed method gives good performance on publicly available datasets.

  1. Change Detection Using High Resolution Remote Sensing Images Based on Active Learning and Markov Random Fields

    Directory of Open Access Journals (Sweden)

    Huai Yu

    2017-11-01

    Full Text Available Change detection has been widely used in remote sensing, such as for disaster assessment and urban expansion detection. Although it is convenient to use unsupervised methods to detect changes from multi-temporal images, the results could be further improved. In supervised methods, heavy data labelling tasks are needed, and the sample annotation process with real categories is tedious and costly. To relieve the burden of labelling and to obtain satisfactory results, we propose an interactive change detection framework based on active learning and Markov random field (MRF. More specifically, a limited number of representative objects are found in an unsupervised way at the beginning. Then, the very limited samples are labelled as “change” or “no change” to train a simple binary classification model, i.e., a Gaussian process model. By using this model, we then select and label the most informative samples by “the easiest” sample selection strategy to update the former weak classification model until the detection results do not change notably. Finally, the maximum a posteriori (MAP change detection is efficiently computed via the min-cut-based integer optimization algorithm. The time consuming and laborious manual labelling process can be reduced substantially, and a desirable detection result can be obtained. The experiments on several WorldView-2 images demonstrate the effectiveness of the proposed method.

  2. Malware Detection Based on Analysis of Activity of the Working Station

    Directory of Open Access Journals (Sweden)

    M. U. Vaganov

    2011-03-01

    Full Text Available It is covered the practical implementation of a malware detection system by analyzing the activity of individual applications and workstation in general. A state vector consists of a set of parameters which are the most exposed to malicious programs. Target platforms are operating systems of Windows: Windows XP, Windows Vista, Windows Seven.

  3. Efficient voice activity detection in reverberant enclosures using far field microphones

    DEFF Research Database (Denmark)

    Petsatodis, Theodore; Boukis, Christos

    2009-01-01

    An algorithm suitable for voice activity detection under reverberant conditions is proposed in this paper. Due to the use of far-filed microphones the proposed solution processes speech signals of highly-varying intensity and signal to noise ratio, that are contaminated with several echoes...

  4. A fast, sensitive and easy colorimetric assay for chitinase and cellulase activity detection.

    NARCIS (Netherlands)

    Ferrari, Alessandro; Gaber, Yasser; Fraaije, Marco

    2014-01-01

    BACKGROUND: Most of the current colorimetric methods for detection of chitinase or cellulase activities on the insoluble natural polymers chitin and cellulose depend on a chemical redox reaction. The reaction involves the reducing ends of the hydrolytic products. The Schales' procedure and the

  5. Detection of extracellular protease activity in different species and genera of ectomycorrhizal fungi.

    Science.gov (United States)

    Nygren, Cajsa M R; Edqvist, Johan; Elfstrand, Malin; Heller, Gregory; Taylor, Andy F S

    2007-05-01

    In northern forest ecosystems, most soil nitrogen (N) is in organic form and forest trees are largely dependent on ectomycorrhizal (ECM) fungi and their degradative abilities for N uptake. The ability of ECM fungi to acquire N from organic substrates should, therefore, be a widespread trait given its ecological importance. However, little is known about the degradative abilities of most ECM fungi as they remain untested due to problems of isolation or extremely slow growth in pure culture. In this paper, we present data on extracellular protease activity of 32 species of ECM fungi, most of which have not previously been cultured. Milk powder plates and zymograms were compared for detecting protease activity in these intractable species. In total, 29/32 of the species produced extracellular protease activity, but detection was method dependent. Growth on milk powder plates detected protease activity in 28 of 32 species, while zymograms only detected proteases in Amanita muscaria, Russula chloroides, Lactarius deterrimus and Lactarius quieticolor. The study supports the hypothesis that protease excretion is a widespread physiological trait in ECM fungi and that this ability is of considerable significance for nitrogen uptake in forest ecosystems.

  6. Telomerase Activity in Breast Tumor Tissues and its Possible use for Detection of Circulating Carcinoma Cells

    Czech Academy of Sciences Publication Activity Database

    Šimíčková, M.; Nekulová, M.; Pecen, Ladislav; Vagundová, M.; Maláska, J.; Obermannová, R.; Lauerová, L.

    2002-01-01

    Roč. 5, - (2002), s. 98 ISSN 1211-8869. [Central European Conference on Human Tumor Markers /4./. 13.02.2003-16.02.2003, Karlovy Vary] Institutional research plan: CEZ:AV0Z1030915 Keywords : telomerase activity * early detection of distant metastases * cancer reccurence Subject RIV: BB - Applied Statistics, Operational Research

  7. Extranuclear detection of histones and nucleosomes in activated human lymphoblasts as an early event in apoptosis.

    NARCIS (Netherlands)

    Gabler, C.; Blank, N.; Hieronymus, T.; Schiller, M.; Berden, J.H.M.; Kalden, J.R.; Lorenz, H.M.

    2004-01-01

    OBJECTIVE: To evaluate the presence of histones and nucleosomes in cell lysates of freshly isolated peripheral blood mononuclear cells (PBMC), fully activated lymphoblasts, or lymphoblasts after induction of apoptosis. METHODS: Each histone class (H1, H2A, H2B, H3, and H4) was detected by western

  8. Electrochemical DNA sensor-based strategy for sensitive detection of DNA demethylation and DNA demethylase activity.

    Science.gov (United States)

    Shen, Qingming; Fan, Mengxing; Yang, Yin; Zhang, Hui

    2016-08-31

    DNA demethylation and demethylase activity play important roles in DNA self-repair, and their detection is key to early diagnosis of fatal diseases. Herein, a facile electrochemical DNA (E-DNA) sensor was developed for the sensitive detection of DNA demethylation and demethylase activity based on an enzyme cleavage strategy. The thiol modified hemi-methylated hairpin probe DNA (pDNA) was self-assembled on a Au electrode surface through the formation of AuS bonds. The hemi-methylated pDNA served as the substrate of DNA demethylase (using methyl-CpG-binding domain protein 2 (MBD2) as an example). Following demethylation, the hairpin stem was then recognized and cleaved by BstUI endonuclease. The ferrocene carboxylic acid (FcA)-tagged pDNA strands were released into the buffer solution from the electrode surface, resulting in a significant decrease of electrochemical signal and providing a means to observe DNA demethylation. The activity of DNA demethylase was analyzed in the concentration ranging from 0.5 to 500 ng mL(-1) with a limit of detection as low as 0.17 ng mL(-1). With high specificity and sensitivity, rapid response, and low cost, this simple E-DNA sensor provides a unique platform for the sensitive detection of DNA demethylation, DNA demethylase activity, and related molecular diagnostics and drug screening. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. A highly sensitive technique for detecting catalytically active nanoparticles against a background of general workplace aerosols

    International Nuclear Information System (INIS)

    Neubauer, N; Weis, F; Seipenbusch, M; Kasper, G; Binder, A

    2011-01-01

    A new measurement technique was studied using catalysis to specifically detect airborne nanoparticles in presence of background particles in the workplace air. Catalytically active nanoparticles produced by spark discharge were used as aerosol catalysts. According to these particles suitable catalytic test reactions were chosen and investigated by two different approaches: catalysis on airborne nanoparticles and catalysis on deposited nanoparticles. The results indicate that catalysis is applicable for the specific measurement of nanoparticles in the workplace air. Catalysis on airborne particles is suitable for the specific detection of very active nanoparticles, e.g. platinum or nickel, at high concentrations of about 10 7 /cm 3 . The approach of catalysis on deposited particles is better suited for nanoparticle aerosols at low concentrations, for slow catalytic reactions or less active nanoparticles like iron oxide (Fe 2 O 3 ). On the basis of the experimental results detection limits in the range of μg or even ng were calculated which assure the good potential of catalysis for the specific detection of nanoparticles in the workplace air based on their catalytic activity.

  10. Facial Video based Detection of Physical Fatigue for Maximal Muscle Activity

    DEFF Research Database (Denmark)

    Haque, Mohammad Ahsanul; Irani, Ramin; Nasrollahi, Kamal

    2016-01-01

    Physical fatigue reveals the health condition of a person at for example health checkup, fitness assessment or rehabilitation training. This paper presents an efficient noncontact system for detecting non-localized physi-cal fatigue from maximal muscle activity using facial videos acquired...

  11. Vehicle Mode and Driving Activity Detection Based on Analyzing Sensor Data of Smartphones.

    Science.gov (United States)

    Lu, Dang-Nhac; Nguyen, Duc-Nhan; Nguyen, Thi-Hau; Nguyen, Ha-Nam

    2018-03-29

    In this paper, we present a flexible combined system, namely the Vehicle mode-driving Activity Detection System (VADS), that is capable of detecting either the current vehicle mode or the current driving activity of travelers. Our proposed system is designed to be lightweight in computation and very fast in response to the changes of travelers' vehicle modes or driving events. The vehicle mode detection module is responsible for recognizing both motorized vehicles, such as cars, buses, and motorbikes, and non-motorized ones, for instance, walking, and bikes. It relies only on accelerometer data in order to minimize the energy consumption of smartphones. By contrast, the driving activity detection module uses the data collected from the accelerometer, gyroscope, and magnetometer of a smartphone to detect various driving activities, i.e., stopping, going straight, turning left, and turning right. Furthermore, we propose a method to compute the optimized data window size and the optimized overlapping ratio for each vehicle mode and each driving event from the training datasets. The experimental results show that this strategy significantly increases the overall prediction accuracy. Additionally, numerous experiments are carried out to compare the impact of different feature sets (time domain features, frequency domain features, Hjorth features) as well as the impact of various classification algorithms (Random Forest, Naïve Bayes, Decision tree J48, K Nearest Neighbor, Support Vector Machine) contributing to the prediction accuracy. Our system achieves an average accuracy of 98.33% in detecting the vehicle modes and an average accuracy of 98.95% in recognizing the driving events of motorcyclists when using the Random Forest classifier and a feature set containing time domain features, frequency domain features, and Hjorth features. Moreover, on a public dataset of HTC company in New Taipei, Taiwan, our framework obtains the overall accuracy of 97.33% that is

  12. Vehicle Mode and Driving Activity Detection Based on Analyzing Sensor Data of Smartphones

    Directory of Open Access Journals (Sweden)

    Dang-Nhac Lu

    2018-03-01

    Full Text Available In this paper, we present a flexible combined system, namely the Vehicle mode-driving Activity Detection System (VADS, that is capable of detecting either the current vehicle mode or the current driving activity of travelers. Our proposed system is designed to be lightweight in computation and very fast in response to the changes of travelers’ vehicle modes or driving events. The vehicle mode detection module is responsible for recognizing both motorized vehicles, such as cars, buses, and motorbikes, and non-motorized ones, for instance, walking, and bikes. It relies only on accelerometer data in order to minimize the energy consumption of smartphones. By contrast, the driving activity detection module uses the data collected from the accelerometer, gyroscope, and magnetometer of a smartphone to detect various driving activities, i.e., stopping, going straight, turning left, and turning right. Furthermore, we propose a method to compute the optimized data window size and the optimized overlapping ratio for each vehicle mode and each driving event from the training datasets. The experimental results show that this strategy significantly increases the overall prediction accuracy. Additionally, numerous experiments are carried out to compare the impact of different feature sets (time domain features, frequency domain features, Hjorth features as well as the impact of various classification algorithms (Random Forest, Naïve Bayes, Decision tree J48, K Nearest Neighbor, Support Vector Machine contributing to the prediction accuracy. Our system achieves an average accuracy of 98.33% in detecting the vehicle modes and an average accuracy of 98.95% in recognizing the driving events of motorcyclists when using the Random Forest classifier and a feature set containing time domain features, frequency domain features, and Hjorth features. Moreover, on a public dataset of HTC company in New Taipei, Taiwan, our framework obtains the overall accuracy of 97

  13. The usefulness of 99mTc-MIBI in the detection of active pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Lee, H. J.; Jeon, D. S.; Yoo, S. D.; Lee, M. K.; Park, S. K.; Kim, S. J.; Kim, I. J.; Kim, Y. K.

    1998-01-01

    The use of radiopharmaceuticals in evaluation of pulmonary tuberculosis may help to resolve difficult diagnostic problems such as discordance between sputum examinations and chest roentgenographic findings. We investigated the usefulness of 99m Tc-methoxyisobutylisonitrile (MIBI) scintigraphy in the detection of active pulmonary tuberculosis. Forty-six patients with suspected active pulmonary tuberculosis were studied with sputum smear of AFB, sputum AFB culture, chest X-ray and MIBI scan. MIBI image was obtained 15 and 60 min after intravenous injection of 370MBq(10mCi) 99m Tc-MIBI. In 16 patients of them Ga scans were performed in addition to MIBI scan. Repeated MIBI scans were done in 7 patients with active pulmonary tuberculosis after 4∼6 months of antituberculous chemotherapy. Thirty-two patients were confirmed as active tuberculosis by sputum culture. Sensitivity of MIBI scan to active tuberculosis was 87.5%(28/32) and MIBI findings were negative in all of 14 patients with inactive disease. Focal uptake of MIBI was dense in the area that was strongly suggested active tuberculous lesions by chest roentgenogram. There was no discordance between MIBI and Ga image in 16 patients. But the uptake areas of Ga images were broader than that of MIBI images. After 4∼6 months of antituberculous treatment all repeated MIBI scans revealed negative findings except 1 patient with persistent active pulmonary tuberculosis due to drug resistance. MIBI scan could be used in the detection of active pulmonary tuberculosis as a useful noninvasive diagnostic tool

  14. Method for improved selectivity in photo-activation and detection of molecular diagnostic agents

    Science.gov (United States)

    Wachter, E.A.; Fisher, W.G.; Dees, H.C.

    1998-11-10

    A method for the imaging of a particular volume of plant or animal tissue, wherein the plant or animal tissue contains at least one photo-active molecular agent. The method includes the steps of treating the particular volume of the plant or animal tissue with light sufficient to promote a simultaneous two-photon excitation of the photo-active molecular agent contained in the particular volume of the plant or animal tissue, photo-activating at least one of the at least one photo-active molecular agent in the particular volume of the plant or animal tissue, thereby producing at least one photo-activated molecular agent, wherein the at least one photo-activated molecular agent emits energy, detecting the energy emitted by the at least one photo-activated molecular agent, and producing a detected energy signal which is characteristic of the particular volume of plant or animal tissue. The present invention is also a method for the imaging of a particular volume of material, wherein the material contains at least one photo-active molecular agent. 13 figs.

  15. MMP activity in the hybrid layer detected with in situ zymography.

    Science.gov (United States)

    Mazzoni, A; Nascimento, F D; Carrilho, M; Tersariol, I; Papa, V; Tjäderhane, L; Di Lenarda, R; Tay, F R; Pashley, D H; Breschi, L

    2012-05-01

    Dentinal proteases are believed to play an important role in the degradation of hybrid layers (HL). This study investigated the HL gelatinolytic activity by in situ zymography and functional enzyme activity assay. The hypotheses were that HLs created by an etch-and-rinse adhesive exhibit active gelatinolytic activity, and MMP-2 and -9 activities in dentin increase during adhesive procedures. Etched-dentin specimens were bonded with Adper Scotchbond 1XT and restored with composite. Adhesive/dentin interface slices were placed on microscope slides, covered with fluorescein-conjugated gelatin, and observed with a multi-photon confocal microscope after 24 hrs. Human dentin powder aliquots were prepared and assigned to the following treatments: A, untreated; B, etched with 10% phosphoric acid; or C, etched with 10% phosphoric acid and mixed with Scotchbond 1XT. The MMP-2 and -9 activities of extracts of dentin powder were measured with functional enzyme assays. Intense and continuous enzyme activity was detected at the bottom of the HL, while that activity was more irregular in the upper HL. Both acid-etching and subsequent adhesive application significantly increased MMP-2 and -9 activities (p < 0.05). The results demonstrate, for the first time, intrinsic MMP activity in the HL, and intense activation of matrix-bound MMP activity with both etching and adhesive application.

  16. Solar 27-day rotational period detected in wide-area lightning activity in Japan

    Science.gov (United States)

    Miyahara, Hiroko; Higuchi, Chika; Terasawa, Toshio; Kataoka, Ryuho; Sato, Mitsuteru; Takahashi, Yukihiro

    2017-04-01

    A signal of the 27-day solar rotational period is often observed in cloud and lightning activities over the globe. Here we provide evidence of the 27-day periodicity of lightning activity in Japan using daily observational records of lightning for AD 1989-2015. The 27-day period is detected with 4.2 standard deviations, but only in wide-area lightning activity covering more than a 105 km2. The 27-day signal is more prominent around the maxima of solar decadal cycles.

  17. Methods, microfluidic devices, and systems for detection of an active enzymatic agent

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, Gregory J; Hatch, Anson V; Singh, Anup K; Wang, Ying-Chih

    2014-10-28

    Embodiments of the present invention provide methods, microfluidic devices, and systems for the detection of an active target agent in a fluid sample. A substrate molecule is used that contains a sequence which may cleave in the presence of an active target agent. A SNAP25 sequence is described, for example, that may be cleaved in the presence of Botulinum Neurotoxin. The substrate molecule includes a reporter moiety. The substrate molecule is exposed to the sample, and resulting reaction products separated using electrophoretic separation. The elution time of the reporter moiety may be utilized to identify the presence or absence of the active target agent.

  18. Solar 27-day rotational period detected in wide-area lightning activity in Japan

    Directory of Open Access Journals (Sweden)

    H. Miyahara

    2017-04-01

    Full Text Available A signal of the 27-day solar rotational period is often observed in cloud and lightning activities over the globe. Here we provide evidence of the 27-day periodicity of lightning activity in Japan using daily observational records of lightning for AD 1989–2015. The 27-day period is detected with 4.2 standard deviations, but only in wide-area lightning activity covering more than a 105 km2. The 27-day signal is more prominent around the maxima of solar decadal cycles.

  19. Machine Learning Detects Pan-cancer Ras Pathway Activation in The Cancer Genome Atlas

    Directory of Open Access Journals (Sweden)

    Gregory P. Way

    2018-04-01

    Full Text Available Summary: Precision oncology uses genomic evidence to match patients with treatment but often fails to identify all patients who may respond. The transcriptome of these “hidden responders” may reveal responsive molecular states. We describe and evaluate a machine-learning approach to classify aberrant pathway activity in tumors, which may aid in hidden responder identification. The algorithm integrates RNA-seq, copy number, and mutations from 33 different cancer types across The Cancer Genome Atlas (TCGA PanCanAtlas project to predict aberrant molecular states in tumors. Applied to the Ras pathway, the method detects Ras activation across cancer types and identifies phenocopying variants. The model, trained on human tumors, can predict response to MEK inhibitors in wild-type Ras cell lines. We also present data that suggest that multiple hits in the Ras pathway confer increased Ras activity. The transcriptome is underused in precision oncology and, combined with machine learning, can aid in the identification of hidden responders. : Way et al. develop a machine-learning approach using PanCanAtlas data to detect Ras activation in cancer. Integrating mutation, copy number, and expression data, the authors show that their method detects Ras-activating variants in tumors and sensitivity to MEK inhibitors in cell lines. Keywords: Gene expression, machine learning, Ras, NF1, KRAS, NRAS, HRAS, pan-cancer, TCGA, drug sensitivity

  20. Application of a novel highly sensitive activity-based probe for detection of cathepsin G.

    Science.gov (United States)

    Zou, Fang; Schmon, Michael; Sienczyk, Marcin; Grzywa, Renata; Palesch, David; Boehm, Bernhard O; Sun, Zi Lin; Watts, Colin; Schirmbeck, Reinhold; Burster, Timo

    2012-02-15

    Cathepsins are crucial in antigen processing in the major histocompatibility complex class II (MHC II) pathway. Within the proteolytic machinery, three classes of proteases (i.e., cysteine, aspartic, and serine proteases) are present in the endocytic compartments. The combined action of these proteases generates antigenic peptides from antigens, which are loaded to MHC II molecules for CD4+ T cell presentation. Detection of active serine proteases in primary human antigen-presenting cells (APCs) is restricted because of the small numbers of cells isolated from the peripheral blood. For this purpose, we developed a novel highly sensitive α-aminoalkylphosphonate diphenyl ester (DAP) activity-based probe to detect the serine protease cathepsin G (CatG) in primary APCs and after Epstein-Barr virus (EBV) exposure. Although CatG activity was not altered after short-term exposure of EBV in primary myeloid dendritic cells 1 (mDC1s), the aspartic protease cathepsin D (CatD) was reduced, suggesting that EBV is responsible for mitigating the presentation of a model antigen tetanus toxoid C-fragment (TTCF) by reduction of CatD. In addition, CatG activity was reduced to background levels in B cells during cell culture; however, these findings were independent of EBV transformation. In conclusion, our activity-based probe can be used for both Western blot and 96-well-based high-throughput CatG detection when cell numbers are limited. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Bootstrap resampling to detect active zone for extreme rainfall in Indonesia

    Science.gov (United States)

    Kuswanto, Heri; Hidayati, Sri; Salamah, Mutiah; Sutijo Ulama, Brodjol

    2017-10-01

    This research aims to develop a methodology to detect active zones related to the extreme rainfall event in one of regions in Indonesia. Active zone is defined as regions or zones on the atmospheric level which have significantly different pattern with other regions prior to the occurrence of extreme event happen in the study area. The detection will be useful for the forecasters to predict the extreme rainfall events, and hence, the risk of the disaster caused by the events can be minimized. In order to predict the active zone, this paper examines statistical procedure that is able to test the significant difference between weather phenomena at the atmospheric level onset with prior to the occurrence.

  2. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    International Nuclear Information System (INIS)

    Park, Jong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Young Ho; Kim, Kyung Soo; Jin, Hyun Seok; Hong, Kyung Won; Oh, Berm Seok; Park, Hun Kuk; Choi, Yong Suk; Hwang, Eui Hwan

    2009-01-01

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52 mm 2 . The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  3. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Young Ho; Kim, Kyung Soo; Jin, Hyun Seok; Hong, Kyung Won; Oh, Berm Seok; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, Kyung Hee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    2009-03-15

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 {mu}m and the range of lesional area was 36.95-138.52 mm{sup 2}. The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  4. Trace elements detection in whole food samples by Neutron Activation Analysis, k{sub 0}-method

    Energy Technology Data Exchange (ETDEWEB)

    Sathler, Márcia Maia; Menezes, Maria Ângela de Barros Correia, E-mail: maia.sathler@gmail.com, E-mail: menezes@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Salles, Paula Maria Borges de, E-mail: pauladesalles@yahoo.com.br [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    Inorganic elements, from natural and anthropogenic sources are present in foods in different concentrations. With the increase in anthropogenic activities, there was also a considerable increase in the emission of these elements in the environment, leading to the need of monitoring the elemental composition of foods available for consumption. Numerous techniques have been used to detect inorganic elements in biological and environmental matrices, always aiming at reaching lower detection limits in order to evaluate the trace element content in the sample. Neutron activation analysis (INAA), applying the k{sub 0}-method, produces accurate and precise results without the need of chemical preparation of the samples – that could cause their contamination. This study evaluated the presence of inorganic elements in whole foods samples, mainly elements on trace levels. For this purpose, seven samples of different types of whole foods were irradiated in the TRIGA MARK I IPR-R1 research reactor - located at CDTN/CNEN, in Belo Horizonte, MG. It was possible to detect twenty two elements above the limit of detection in, at least, one of the samples analyzed. This study reaffirms the INAA, k{sub 0} - method, as a safe and efficient technique for detecting trace elements in food samples. (author)

  5. Trace elements detection in whole food samples by Neutron Activation Analysis, k0-method

    International Nuclear Information System (INIS)

    Sathler, Márcia Maia; Menezes, Maria Ângela de Barros Correia; Salles, Paula Maria Borges de

    2017-01-01

    Inorganic elements, from natural and anthropogenic sources are present in foods in different concentrations. With the increase in anthropogenic activities, there was also a considerable increase in the emission of these elements in the environment, leading to the need of monitoring the elemental composition of foods available for consumption. Numerous techniques have been used to detect inorganic elements in biological and environmental matrices, always aiming at reaching lower detection limits in order to evaluate the trace element content in the sample. Neutron activation analysis (INAA), applying the k 0 -method, produces accurate and precise results without the need of chemical preparation of the samples – that could cause their contamination. This study evaluated the presence of inorganic elements in whole foods samples, mainly elements on trace levels. For this purpose, seven samples of different types of whole foods were irradiated in the TRIGA MARK I IPR-R1 research reactor - located at CDTN/CNEN, in Belo Horizonte, MG. It was possible to detect twenty two elements above the limit of detection in, at least, one of the samples analyzed. This study reaffirms the INAA, k 0 - method, as a safe and efficient technique for detecting trace elements in food samples. (author)

  6. Kernel-Based Sensor Fusion With Application to Audio-Visual Voice Activity Detection

    Science.gov (United States)

    Dov, David; Talmon, Ronen; Cohen, Israel

    2016-12-01

    In this paper, we address the problem of multiple view data fusion in the presence of noise and interferences. Recent studies have approached this problem using kernel methods, by relying particularly on a product of kernels constructed separately for each view. From a graph theory point of view, we analyze this fusion approach in a discrete setting. More specifically, based on a statistical model for the connectivity between data points, we propose an algorithm for the selection of the kernel bandwidth, a parameter, which, as we show, has important implications on the robustness of this fusion approach to interferences. Then, we consider the fusion of audio-visual speech signals measured by a single microphone and by a video camera pointed to the face of the speaker. Specifically, we address the task of voice activity detection, i.e., the detection of speech and non-speech segments, in the presence of structured interferences such as keyboard taps and office noise. We propose an algorithm for voice activity detection based on the audio-visual signal. Simulation results show that the proposed algorithm outperforms competing fusion and voice activity detection approaches. In addition, we demonstrate that a proper selection of the kernel bandwidth indeed leads to improved performance.

  7. Detection of cortical activities on eye movement using functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Masaki; Kawai, Kazushige; Kitahara, Kenji [Jikei Univ., Tokyo (Japan). School of Medicine; Soulie, D.; Cordoliani, Y.S.; Iba-Zizen, M.T.; Cabanis, E.A.

    1997-11-01

    Cortical activity during eye movement was examined with functional magnetic resonance imaging. Horizontal saccadic eye movements and smooth pursuit eye movements were elicited in normal subjects. Activity in the frontal eye field was found during both saccadic and smooth pursuit eye movements at the posterior margin of the middle frontal gyrus and in parts of the precentral sulcus and precentral gyrus bordering the middle frontal gyrus (Brodmann`s areas 8, 6, and 9). In addition, activity in the parietal eye field was found in the deep, upper margin of the angular gyrus and of the supramarginal gyrus (Brodmann`s areas 39 and 40) during saccadic eye movement. Activity of V5 was found at the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus during smooth pursuit eye movement. Our results suggest that functional magnetic resonance imaging is useful for detecting cortical activity during eye movement. (author)

  8. Detection of cortical activities on eye movement using functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yoshida, Masaki; Kawai, Kazushige; Kitahara, Kenji; Soulie, D.; Cordoliani, Y.S.; Iba-Zizen, M.T.; Cabanis, E.A.

    1997-01-01

    Cortical activity during eye movement was examined with functional magnetic resonance imaging. Horizontal saccadic eye movements and smooth pursuit eye movements were elicited in normal subjects. Activity in the frontal eye field was found during both saccadic and smooth pursuit eye movements at the posterior margin of the middle frontal gyrus and in parts of the precentral sulcus and precentral gyrus bordering the middle frontal gyrus (Brodmann's areas 8, 6, and 9). In addition, activity in the parietal eye field was found in the deep, upper margin of the angular gyrus and of the supramarginal gyrus (Brodmann's areas 39 and 40) during saccadic eye movement. Activity of V5 was found at the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus during smooth pursuit eye movement. Our results suggest that functional magnetic resonance imaging is useful for detecting cortical activity during eye movement. (author)

  9. Evaluation of the carbapenem inactivation method (CIM) for detecting carbapenemase activity in enterobacteria.

    Science.gov (United States)

    Aguirre-Quiñonero, A; Cano, M E; Gamal, D; Calvo, J; Martínez-Martínez, L

    2017-07-01

    The objective of this study was to evaluate the accuracy of the CIM test in the detection of carbapenemase activity in 124 strains of Enterobacteriaceae. A panel of 124 previously characterized Enterobacteriaceae was tested: 77 strains producing the following carbapenemase families: KPC (n = 14), GES (n = 22), NDM (n = 19), VIM (n = 4), IMP (n = 4) and OXA-48 (n = 14) and 47 non-carbapenemase producers. For the CIM method, an active susceptibility meropenem disc was exposed to a bacterial suspension of a test strain; when a carbapenemase is produced, the antibiotic is inactivated allowing uninhibited growth of an indicator strain after overnight incubation. A clear inhibition zone (≥20 mm) was considered indicative of no-carbapenemase activity. All KPC, NDM, VIM, IMP or OXA-48 producing strains were unequivocally detected with the CIM test. CIM false negative results were obtained with eleven Enterobacter cloacae producing GES-6. Two other E. cloacae not producing carbapenemase (one with SHV-12, one hyperproducing AmpC) were positive by the test. The sensitivity and specificity of the assay compared to those of molecular methods were 85.7% and 95.7%, respectively. The CIM method proved to be inexpensive and easy to interpret. It provided less than optimal results in the detection of GES-6 activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Detection of Aryl Hydrocarbon Receptor Activation by Some Chemicals in Food Using a Reporter Gene Assay.

    Science.gov (United States)

    Amakura, Yoshiaki; Tsutsumi, Tomoaki; Yoshimura, Morio; Nakamura, Masafumi; Handa, Hiroshi; Matsuda, Rieko; Teshima, Reiko; Watanabe, Takahiro

    2016-02-25

    The purpose of this study was to examine whether a simple bioassay used for the detection of dioxins (DXNs) could be applied to detect trace amounts of harmful DXN-like substances in food products. To identify substances with possible DXN-like activity, we assessed the ability of various compounds in the environment to bind the aryl hydrocarbon receptor (AhR) that binds specifically to DXNs. The compounds tested included 19 polycyclic aromatic hydrocarbons (PAHs), 20 PAH derivatives (nitrated, halogenated, and aminated derivatives), 23 pesticides, six amino acids, and eight amino acid metabolites. The AhR binding activities (AhR activity) of these compounds were measured using the chemical activated luciferase gene expression (CALUX) reporter gene assay system. The majority of the PAHs exhibited marked AhR activity that increased in a concentration-dependent manner. Furthermore, there was a positive link between AhR activity and the number of aromatic rings in the PAH derivatives. Conversely, there appeared to be a negative correlation between AhR activity and the number of chlorine residues present on halogenated PAH derivatives. However, there was no correlation between AhR activity and the number and position of substituents among nitrated and aminated derivatives. Among the pesticides tested, the indole-type compounds carbendazim and thiabendazole showed high levels of activity. Similarly, the indole compound tryptamine was the only amino acid metabolite to induce AhR activity. The results are useful in understanding the identification and characterization of AhR ligands in the CALUX assay.

  11. INTEGRAL/IBIS detects renewed activity from H 1417-624

    DEFF Research Database (Denmark)

    Fiocchi, M.; Sguera, A.; Sidoli, L.

    2014-01-01

    During a recent INTEGRAL Galactic Plane Scanning observation (PI: A. Bazzano), started on 2014 January 19 at 07:51 UTC, IBIS/ISGRI detected renewed activity from the transient system H 1417-624. The source H 1417-624 was detected at about 10 sigma in the IBIS map 18-40 keV, with a flux of 14....... H 1417-624 is a Be X-ray Transient (Apparao et al. 1980, A&A 89, 249; Grindlay et al. 1984, ApJ 276, 621) showing a neutron star spin period of 17.54 s and an orbital period of 42.12 days (Finger et al. 1996, A&A Supp. Ser. 120, 209). It was previously detected in 1994 and 1995 (during a strong type...

  12. Voice Activity Detection in Noisy Environments Based on Double-Combined Fourier Transform and Line Fitting

    Directory of Open Access Journals (Sweden)

    Jinsoo Park

    2014-01-01

    Full Text Available A new voice activity detector for noisy environments is proposed. In conventional algorithms, the endpoint of speech is found by applying an edge detection filter that finds the abrupt changing point in a feature domain. However, since the frame energy feature is unstable in noisy environments, it is difficult to accurately find the endpoint of speech. Therefore, a novel feature extraction algorithm based on the double-combined Fourier transform and envelope line fitting is proposed. It is combined with an edge detection filter for effective detection of endpoints. Effectiveness of the proposed algorithm is evaluated and compared to other VAD algorithms using two different databases, which are AURORA 2.0 database and SITEC database. Experimental results show that the proposed algorithm performs well under a variety of noisy conditions.

  13. Voice activity detection in noisy environments based on double-combined fourier transform and line fitting.

    Science.gov (United States)

    Park, Jinsoo; Kim, Wooil; Han, David K; Ko, Hanseok

    2014-01-01

    A new voice activity detector for noisy environments is proposed. In conventional algorithms, the endpoint of speech is found by applying an edge detection filter that finds the abrupt changing point in a feature domain. However, since the frame energy feature is unstable in noisy environments, it is difficult to accurately find the endpoint of speech. Therefore, a novel feature extraction algorithm based on the double-combined Fourier transform and envelope line fitting is proposed. It is combined with an edge detection filter for effective detection of endpoints. Effectiveness of the proposed algorithm is evaluated and compared to other VAD algorithms using two different databases, which are AURORA 2.0 database and SITEC database. Experimental results show that the proposed algorithm performs well under a variety of noisy conditions.

  14. Power and Society: the Activities of the Novorossiysk Detective Department in 1912 year

    Directory of Open Access Journals (Sweden)

    Anvar M. Mamadaliev

    2015-09-01

    Full Text Available The article is devoted to the study of the relationships between power structures in the face of law enforcement and society in the Black Sea province in 1912 year, through the analysis of the activities of the Novorossiysk detective department. The article studies the reports, regulations, and other documents of Novorossiysk police detective branch, on the basis of which the author talks about the General atmosphere of relationships between the authorities and society in the period. Most of used sources are published for the first time. The author comes to the conclusion that the organization of detective business in Novorossiysk was carefully planned and prepared, and rather quickly embodied in practice. Even after the recent revolutionary events (1905-1907 years there is no written evidence that the society in 1912 was perceived by the employees of law enforcement negatively. However, the authorities are rightly feared of the iterance of public outbursts that are clearly expressed in the historical sources.

  15. Multisensor fusion for atrial and ventricular activity detection in coronary care monitoring.

    Science.gov (United States)

    Hernández, A I; Carrault, G; Mora, F; Thoraval, L; Passariello, G; Schleich, J M

    1999-10-01

    Information management for critical care monitoring is still a very difficult task. Medical staff is often overwhelmed by the amount of data provided by the increased number of specific monitoring devices and instrumentation, and the lack of an effective automated system. Specifically, a basic task such as arrhythmia detection still produce an important amount of undesirable alarms, due in part to the mechanistic approach of current monitoring systems. In this work, multisensor and multisource data fusion schemes to improve atrial and ventricular activity detection in critical care environments are presented. Applications of these schemes are quantitatively evaluated and compared with current methods, showing the potential advantages of data fusion techniques for event detection in noise corrupted signals.

  16. Physical activity and associations with computed tomography-detected lumbar zygapophyseal joint osteoarthritis.

    Science.gov (United States)

    Suri, Pradeep; Hunter, David J; Boyko, Edward J; Rainville, James; Guermazi, Ali; Katz, Jeffrey N

    2015-01-01

    There are no previous epidemiologic studies examining associations between physical activity and imaging-detected lumbar zygapophyseal joint osteoarthritis (ZJO) in a community-based sample. To determine whether physical activity is associated with prevalent lumbar ZJO on computed tomography (CT). A community-based cross-sectional study. Four hundred twenty-four older adults from the Framingham Heart Study. Participants received standardized CT assessments of lumbar ZJO at the L2-S1 levels. Severe lumbar ZJO was defined according to the presence and/or degree of joint space narrowing, osteophytosis, articular process hypertrophy, articular erosions, subchondral cysts, and intra-articular vacuum phenomenon. This definition of lumbar ZJO was based entirely on CT imaging findings and did not include any clinical criteria such as low back pain. Physical activity was measured using the Physical Activity Index, which estimate hours per day typically spent in these activity categories: sleeping, sitting, slight activity, moderate activity, and heavy activity. Participants reported on usual frequency of walking, running, swimming, and weightlifting. We used multivariable logistic regression to examine associations between self-reported activity and severe lumbar ZJO, while adjusting for key covariates including age, sex, height, and weight. In multivariable analyses, ordinal categories of heavy physical activity duration per day were significantly associated with severe lumbar ZJO (p for trend=.04), with the greatest risk observed for the category 3 or more hours per day, odds ratio 2.13 (95% confidence interval [CI] 0.97-4.67). When heavy activity was modeled as a continuous independent variable, each hour was independently associated with 1.19 times the odds of severe lumbar ZJO (95% CI 1.03-1.38, p=.02). Less vigorous types of physical activity and the type of exercise were not associated with severe lumbar ZJO. Older age, lesser height, and greater weight were

  17. Detection of enteric viruses in activated sludge by feasible concentration methods.

    Science.gov (United States)

    Prado, Tatiana; Gaspar, Ana Maria Coimbra; Miagostovich, Marize Pereira

    2014-01-01

    Human enteric viruses are responsible to cause several diseases, including gastroenteritis and hepatitis, and can be present in high amounts in sewage sludge. This study compared virus recovery efficiency of two feasible concentration methods used for detecting human adenovirus (HAdV), rotavirus species A (RV-A), norovirus genogroup II (NoV GII) and hepatitis A virus (HAV) in sewage sludge from an activated sludge process. Twelve sewage sludge samples were collected bi-monthly from January to July, 2011. Ultracentrifugation was compared with a simplified protocol based on beef extract elution for recovering enteric viruses. Viruses were quantified by quantitative real-time PCR assays and virus recovery efficiency and limits of detection were determined. Methods showed mean recovery rates lower than 7.5%, presenting critical limits of detection (higher than 10(2) - 10(3) genome copies - GC L(-1) for all viruses analyzed). Nevertheless, HAdV were detected in 90% of the analyzed sewage sludge samples (range: 1.8 × 10(4) to 1.1 × 10(5) GC L(-1)), followed by RV-A and NoV (both in 50%) and HAV (8%). Results suggesting that activated sludge is contaminated with high viral loads and HAdV are widely disseminated in these samples. The low virus recovery rates achieved, especially for HAV, indicate that other feasible concentration methods could be developed to improve virus recovery efficiency in these environmental matrices.

  18. Mass Spectrometric Detection of Botulinum Neurotoxin by Measuring its Activity in Serum and Milk

    Science.gov (United States)

    Kalb, Suzanne R.; Pirkle, James L.; Barr, John R.

    Botulinum neurotoxins (BoNTs) are bacterial protein toxins which are considered likely agents for bioterrorism due to their extreme toxicity and high availability. A new mass spectrometry based assay called Endopep MS detects and defines the toxin serotype in clinical and food matrices via toxin activity upon a peptide substrate which mimics the toxin's natural target. Furthermore, the subtype of the toxin is differentiated by employing mass spectrometry based proteomic techniques on the same sample. The Endopep-MS assay selectively detects active BoNT and defines the serotype faster and with sensitivity greater than the mouse bioassay. One 96-well plate can be analyzed in under 7 h. On higher level or "hot" samples, the subtype can then be differentiated in less than 2 h with no need for DNA.

  19. Visual attention based detection of signs of anthropogenic activities in satellite imagery

    Energy Technology Data Exchange (ETDEWEB)

    Skurikhin, Alexei N [Los Alamos National Laboratory

    2010-10-13

    With increasing deployment of satellite imaging systems, only a small fraction of collected data can be subject to expert scrutiny. We present and evaluate a two-tier approach to broad area search for signs of anthropogenic activities in high-resolution commercial satellite imagery. The method filters image information using semantically oriented interest points by combining Harris corner detection and spatial pyramid matching. The idea is that anthropogenic structures, such as rooftop outlines, fence corners, road junctions, are locally arranged in specific angular relations to each other. They are often oriented at approximately right angles to each other (which is known as rectilinearity relation). Detecting the rectilinearity provides an opportunity to highlight regions most likely to contain anthropogenic activity. This is followed by supervised classification of regions surrounding the detected corner points as man-made vs. natural scenes. We consider, in particular, a search for anthropogenic activities in uncluttered areas. In this paper, we proposed and evaluated a two-tier approach to broad area search for signs of anthropogenic activities. Results from experiments on high-resolution ({approx}0.6m) commercial satellite image data showed the potential applicability of this approach and its ability of achieving both high precision and recall rates. The main advantage of combining corner-based cueing with general object recognition is that the incorporation of domain specific knowledge even in its more general form, such as presence of comers, provides a useful cue to narrow the focus of search for signs of anthropogenic activities. Combination of comer based cueing with spatial pyramid matching addressed the issue of comer categorization. An important practical issue for further research is optimizing the balance between false positive and false negative rates. While the results presented in the paper are encouraging, the problem of an automated broad area

  20. Using Electronic Neutron Generators in Active Interrogation to Detect Shielded Fissionable Material

    Science.gov (United States)

    Chichester, David L.; Seabury, Edward H.

    2009-04-01

    Experiments have been performed at Idaho National Laboratory to study methodology and instrumentation for performing neutron active interrogation die-away analyses for the purpose of detecting shielded fissionable material. Here we report initial work using a portable DT electronic neutron generator with a 3He neutron detector to detect shielded fissionable material including enriched uranium and reactor grade plutonium. Measurements have been taken of bare material as well as of material hidden within a large plywood cube. Results from this work have demonstrated the efficacy of the die-away neutron measurement technique for quickly detecting the presence of special nuclear material hidden within plywood shields by analyzing the time dependent neutron signals in-between neutron generator pulses. Using a DT electronic neutron generator operating at 300 Hz with a yield of approximately 0.36 times 108 neutrons per second, 2.2 kg of enriched uranium hidden within a 61 cm times 61 cm times 71 cm volume of plywood was positively detected with a measurement signal 2-sigma above the passive background within 1 second. Similarly, for a 500 second measurement period a lower detection limit approaching the gram level could be expected with the same simple set-up.

  1. Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging

    Directory of Open Access Journals (Sweden)

    Karlien D’huys

    2016-11-01

    Full Text Available Packaging protects food products from environmental influences, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the quality of the packaging material and of the closure or seal. A common problem possibly jeopardizing seal quality is the presence of seal contamination, which can cause a decreased seal strength, an increased packaging failure risk and leak formation. Therefore, early detection and removal of seal contaminated packages from the production chain is crucial. In this work, a pulsed-type active thermography method using the heated seal bars as an excitation source was studied for detecting seal contamination. Thermal image sequences of contaminated seals were recorded shortly after sealing. The detection performances of six thermal image processing methods, based on a single frame, a fit of the cooling profiles, thermal signal reconstruction, pulsed phase thermography, principal component thermography and a matched filter, were compared. High resolution digital images served as a reference to quantify seal contamination, and processed thermal images were mapped to these references. The lowest detection limit (equivalent diameter 0.60 mm was obtained for the method based on a fit of the cooling profiles. Moreover, the detection performance of this method did not depend strongly on the time after sealing at which recording of the thermal images was started, making it a robust and generally applicable method.

  2. Unbalance detection in rotor systems with active bearings using self-sensing piezoelectric actuators

    Science.gov (United States)

    Ambur, Ramakrishnan; Rinderknecht, Stephan

    2018-03-01

    Machines which are developed today are highly automated due to increased use of mechatronic systems. To ensure their reliable operation, fault detection and isolation (FDI) is an important feature along with a better control. This research work aims to achieve and integrate both these functions with minimum number of components in a mechatronic system. This article investigates a rotating machine with active bearings equipped with piezoelectric actuators. There is an inherent coupling between their electrical and mechanical properties because of which they can also be used as sensors. Mechanical deflection can be reconstructed from these self-sensing actuators from measured voltage and current signals. These virtual sensor signals are utilised to detect unbalance in a rotor system. Parameters of unbalance such as its magnitude and phase are detected by parametric estimation method in frequency domain. Unbalance location has been identified using hypothesis of localization of faults. Robustness of the estimates against outliers in measurements is improved using weighted least squares method. Unbalances are detected in a real test bench apart from simulation using its model. Experiments are performed in stationary as well as in transient case. As a further step unbalances are estimated during simultaneous actuation of actuators in closed loop with an adaptive algorithm for vibration minimisation. This strategy could be used in systems which aim for both fault detection and control action.

  3. On the definition of the detection limit for non-selective determination of low activities

    International Nuclear Information System (INIS)

    Tschurlovits, M.

    1977-01-01

    Based on the latest published results, a detection limit which is easy to use in practical work without intensive consideration of counting statistics, is presented. The primary application of the given definition is the determination of gross activity. In the definition the error of the second kind as well as one-sided boundedness of the normal distribution are included. The results are given in graphical form. (orig.) [de

  4. A Support Vector Machine-Based Voice Activity Detection Employing Effective Feature Vectors

    Science.gov (United States)

    Jo, Q.-Haing; Park, Yun-Sik; Lee, Kye-Hwan; Chang, Joon-Hyuk

    In this letter, we propose effective feature vectors to improve the performance of voice activity detection (VAD) employing a support vector machine (SVM), which is known to incorporate an optimized nonlinear decision over two different classes. To extract the effective feature vectors, we present a novel scheme that combines the a posteriori SNR, a priori SNR, and predicted SNR, widely adopted in conventional statistical model-based VAD.

  5. Enhanced Voice Activity Detection Using Modified Wiener Filtering and Harmonic Structure Information

    Directory of Open Access Journals (Sweden)

    Yan ZHANG

    2014-03-01

    Full Text Available Accurate and effective Voice Activity Detection (VAD is a fundamental step for robust speech and speaker recognition. In this study, we propose a robust VAD algorithm based on Modified Wiener Filtering and Harmonic Structure Information. Effectiveness of the proposed algorithm is evaluated by using some well-known databases. Experimental results show that the proposed method performs well under a variety of noisy conditions.

  6. Detailed leak detection test plan and schedule for the Oak Ridge National Laboratory LLLW active tanks

    International Nuclear Information System (INIS)

    Douglas, D.G.; Maresca, J.W. Jr.

    1993-03-01

    This document provides a detailed leak detection test plan and schedule for leak testing many of the tanks that comprise the active portion of the liquid low-level waste (LLLW) system at the Oak Ridge National Laboratory (ORNL). This plan was prepared in response to the requirements of the Federal Facility Agreement (FFA) between the US Department of Energy (DOE) and two other agencies, the US Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation (TDEC)

  7. Application of Statistical Methods to Activation Analytical Results near the Limit of Detection

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Wanscher, B.

    1978-01-01

    Reporting actual numbers instead of upper limits for analytical results at or below the detection limit may produce reliable data when these numbers are subjected to appropriate statistical processing. Particularly in radiometric methods, such as activation analysis, where individual standard...... deviations of analytical results may be estimated, improved discrimination may be based on the Analysis of Precision. Actual experimental results from a study of the concentrations of arsenic in human skin demonstrate the power of this principle....

  8. Detection of low activities 90Sr and 137Cs in surface, subsoil and sewage waters

    International Nuclear Information System (INIS)

    Babenko, V.; Isaev, A.; Kazymyrova, G.; Rudyk, O.; Khristenko, U.

    2004-01-01

    In this article the methodic of detection of volumetric activity of radionuclide 90 Sr in surface, subsoil and sewage waters on the basis of measurement of counting samples using beta-spectrometers SEB-01, produced by RPE 'Atom Komplex Prylad' (RPE 'AKP') and mathematical proceeding of spectra by software packages AKWin. At that, the time of receiving of result shortens, comparing to method of radiochemistry, from 14 days to 3 days. Activity measurement range of beta-spectrometers SEB-01 is 0.1-10 4 Bq/l, that by corresponding radionuclides concentration, allows providing control of water objects according to national norms of Ukraine (2 Bq/l). (authors)

  9. Composite Event Specification and Detection for Supporting Active Capability in an OODBMS: Semantics Architecture and Implementation.

    Science.gov (United States)

    1995-03-01

    For all outgoing edges i from ’n’ propagate parameters in node ’n’ to the nodei connected by edge i activate-operator-node( nodej ); Delete propagated...El E2 Figure 6: Detection of X in recent mode PROCEDURE activate-operator-node( nodej ) /* Recent Context */ CASE nodei is of type a primitive or...composite event has been signalled to nodej */ AND(E1, E2): if left event el is signalled if E2’s list is not empty Pass <e2, el> to the parent Replace el in

  10. Detection of a crack-like conduit beneath the active crater at Aso Volcano Japan

    Science.gov (United States)

    Yamamoto, Mare; Kawakatsu, Hitoshi; Kaneshima, Satoshi; Mori, Takehiko; Tsutsui, Tomoki; Sudo, Yasuaki; Morita, Yuichi

    To constrain the source of long period tremors (LPTs), we deployed a very dense broadband seismic network consisting of totally twenty-four stations around the active crater of Aso volcano in Kyushu, Japan. The spatial variation of the observed signal amplitudes reveals that the source of LPTs consists of an isotropic expansion (contraction) and an inflation (deflation) of an inclined tensile crack with a strike almost parallel to the chain of craters. The detected crack has a dimension of 1 km and its center is located a few hundred meters southwest of the active crater, at a depth of about 1.8 km. The extension of the crack plane meets the crater chain including the active fumarole at the surface, suggesting that the crack has played an important role in transporting gasses and/or lava to the craters from below. This work also demonstrates a powerful usage of broadband seismometers as geodetic instruments to constrain subsurface structures at active volcanoes.

  11. Is the detection of optical activity in extraterrestrial samples a safe indicator for life?

    Science.gov (United States)

    Thiemann, W

    1975-01-01

    Since Pasteur's times it has been accepted that optical activity and life are intimately correlated with each other, i.e. the one could not exist without the other. This argument logically allows the following speculation related to interplanetary exploration: detection of optical activity in an extraterrestrial sample would be the most straightforward proof of the existence of living matter outside the earth. On the other hand it has been shown that spontaneous production of optical activity can be achieved without the help of living matter, so that the close association of optical activity with life is not necessarily true. The paper discusses the possibilities which allow a proof of some sort of life on other planets by polarimetric methods.

  12. Rapid Detection of Glycogen Synthase Kinase-3 Activity in Mouse Sperm Using Fluorescent Gel Shift Electrophoresis

    Directory of Open Access Journals (Sweden)

    Hoseok Choi

    2016-04-01

    Full Text Available Assaying the glycogen synthase kinase-3 (GSK3 activity in sperm is of great importance because it is closely implicated in sperm motility and male infertility. While a number of studies on GSK3 activity have relied on labor-intensive immunoblotting to identify phosphorylated GSK3, here we report the simple and rapid detection of GSK3 activity in mouse sperm using conventional agarose gel electrophoresis and a fluorescent peptide substrate. When a dye-tethered and prephosphorylated (primed peptide substrate for GSK3 was employed, a distinct mobility shift in the fluorescent bands on the agarose was observed by GSK3-induced phosphorylation of the primed peptides. The GSK3 activity in mouse testes and sperm were quantifiable by gel shift assay with low sample consumption and were significantly correlated with the expression levels of GSK3 and p-GSK3. We suggest that our assay can be used for reliable and rapid detection of GSK3 activity in cells and tissue extracts.

  13. Incremental Activation Detection for Real-Time fMRI Series Using Robust Kalman Filter

    Directory of Open Access Journals (Sweden)

    Liang Li

    2014-01-01

    Full Text Available Real-time functional magnetic resonance imaging (rt-fMRI is a technique that enables us to observe human brain activations in real time. However, some unexpected noises that emerged in fMRI data collecting, such as acute swallowing, head moving and human manipulations, will cause much confusion and unrobustness for the activation analysis. In this paper, a new activation detection method for rt-fMRI data is proposed based on robust Kalman filter. The idea is to add a variation to the extended kalman filter to handle the additional sparse measurement noise and a sparse noise term to the measurement update step. Hence, the robust Kalman filter is designed to improve the robustness for the outliers and can be computed separately for each voxel. The algorithm can compute activation maps on each scan within a repetition time, which meets the requirement for real-time analysis. Experimental results show that this new algorithm can bring out high performance in robustness and in real-time activation detection.

  14. Photodynamic quenched cathepsin activity based probes for cancer detection and macrophage targeted therapy.

    Science.gov (United States)

    Ben-Nun, Yael; Merquiol, Emmanuelle; Brandis, Alexander; Turk, Boris; Scherz, Avigdor; Blum, Galia

    2015-01-01

    Elevated cathepsins levels and activities are found in several types of human cancer, making them valuable biomarkers for detection and targeting therapeutics. We designed small molecule quenched activity-based probes (qABPs) that fluoresce upon activity-dependent covalent modification, yielding cell killing by Photodynamic Therapy (PDT). These novel molecules are highly selective theranostic probes that enable both detection and treatment of cancer with minimal side effects. Our qABPs carry a photosensitizer (PS), which is activated by light, resulting in oxidative stress and subsequent cell ablation, and a quencher that when removed by active cathepsins allow the PS to fluoresce and demonstrate PD properties. Our most powerful and stable PS-qABP, YBN14, consists of a selective cathepsin recognition sequence, a QC-1 quencher and a new bacteriochlorin derivative as a PS. YBN14 allowed rapid and selective non-invasive in vivo imaging of subcutaneous tumors and induced specific tumor macrophage apoptosis by light treatment, resulting in a substantial tumor shrinkage in an aggressive breast cancer mouse model. These results demonstrate for the first time that the PS-qABPs technology offers a functional theranostic tool, which can be applied to numerous tumor types and other inflammation-associated diseases.

  15. Telomerase Activity Detected by Quantitative Assay in Bladder Carcinoma and Exfoliated Cells in Urine

    Directory of Open Access Journals (Sweden)

    Roberta Fedriga

    2001-01-01

    Full Text Available Early diagnosis is one of the most determining factors for patient survival. The detection of telomerase activity is a potentially promising tool in the diagnosis of bladder and other types of cancer due to the high expression of this enzyme in tumor cells. We carried out a quantitative evaluation of telomerase activity in urine samples in an attempt to determine a cut-off capable of identifying cancer patients. Telomerase activity was quantified by fluorescence TRAP assay in urine from 50 healthy volunteers and in urine and bioptic tumor samples from 56 previously untreated bladder cancer patients and expressed in arbitrary enzymatic units (AEU. Telomerase activity in urine ranged from 0 to 106 AEU (median 0 in healthy donors and from 0 to 282 AEU (median 87 in patients with cancer. A telomerase expression higher than the cut off value determined by receiver operating characteristic (ROC analysis was observed in 78% of cases, regardless of tumor grade and in 71% (15/21 of cases of nonassessable or negative cytology. The quantitative analysis of telomerase activity in urine enabled us to define cut-off values characterized by different sensitivity and specificity. Cytologic and telomerase determination, used sequentially, enabled us to detect about 90% of tumors.

  16. A 3-Step Algorithm Using Region-Based Active Contours for Video Objects Detection

    Directory of Open Access Journals (Sweden)

    Stéphanie Jehan-Besson

    2002-06-01

    Full Text Available We propose a 3-step algorithm for the automatic detection of moving objects in video sequences using region-based active contours. First, we introduce a very full general framework for region-based active contours with a new Eulerian method to compute the evolution equation of the active contour from a criterion including both region-based and boundary-based terms. This framework can be easily adapted to various applications, thanks to the introduction of functions named descriptors of the different regions. With this new Eulerian method based on shape optimization principles, we can easily take into account the case of descriptors depending upon features globally attached to the regions. Second, we propose a 3-step algorithm for detection of moving objects, with a static or a mobile camera, using region-based active contours. The basic idea is to hierarchically associate temporal and spatial information. The active contour evolves with successively three sets of descriptors: a temporal one, and then two spatial ones. The third spatial descriptor takes advantage of the segmentation of the image in intensity homogeneous regions. User interaction is reduced to the choice of a few parameters at the beginning of the process. Some experimental results are supplied.

  17. Flow cytometric-membrane potential detection of sodium channel active marine toxins: application to ciguatoxins in fish muscle and feasibility of automating saxitoxin detection.

    Science.gov (United States)

    Manger, Ronald; Woodle, Doug; Berger, Andrew; Dickey, Robert W; Jester, Edward; Yasumoto, Takeshi; Lewis, Richard; Hawryluk, Timothy; Hungerford, James

    2014-01-01

    Ciguatoxins are potent neurotoxins with a significant public health impact. Cytotoxicity assays have allowed the most sensitive means of detection of ciguatoxin-like activity without reliance on mouse bioassays and have been invaluable in studying outbreaks. An improvement of these cell-based assays is presented here in which rapid flow cytometric detection of ciguatoxins and saxitoxins is demonstrated using fluorescent voltage sensitive dyes. A depolarization response can be detected directly due to ciguatoxin alone; however, an approximate 1000-fold increase in sensitivity is observed in the presence of veratridine. These results demonstrate that flow cytometric assessment of ciguatoxins is possible at levels approaching the trace detection limits of our earlier cytotoxicity assays, however, with a significant reduction in analysis time. Preliminary results are also presented for detection of brevetoxins and for automation and throughput improvements to a previously described method for detecting saxitoxins in shellfish extracts.

  18. Topic detection using paragraph vectors to support active learning in systematic reviews.

    Science.gov (United States)

    Hashimoto, Kazuma; Kontonatsios, Georgios; Miwa, Makoto; Ananiadou, Sophia

    2016-08-01

    Systematic reviews require expert reviewers to manually screen thousands of citations in order to identify all relevant articles to the review. Active learning text classification is a supervised machine learning approach that has been shown to significantly reduce the manual annotation workload by semi-automating the citation screening process of systematic reviews. In this paper, we present a new topic detection method that induces an informative representation of studies, to improve the performance of the underlying active learner. Our proposed topic detection method uses a neural network-based vector space model to capture semantic similarities between documents. We firstly represent documents within the vector space, and cluster the documents into a predefined number of clusters. The centroids of the clusters are treated as latent topics. We then represent each document as a mixture of latent topics. For evaluation purposes, we employ the active learning strategy using both our novel topic detection method and a baseline topic model (i.e., Latent Dirichlet Allocation). Results obtained demonstrate that our method is able to achieve a high sensitivity of eligible studies and a significantly reduced manual annotation cost when compared to the baseline method. This observation is consistent across two clinical and three public health reviews. The tool introduced in this work is available from https://nactem.ac.uk/pvtopic/. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Active pulmonary tuberculosis case detection and treatment among floating population in China: an effective pilot.

    Science.gov (United States)

    Li, Xinxu; Zhang, Hui; Jiang, Shiwen; Wang, Jia; Liu, Xiaoqiu; Li, Weibin; Yao, Hongyan; Wang, Lixia

    2010-12-01

    China has more and more floating population because of reform and opening-up. As one of the high burden countries in tuberculosis (TB) control in the world, China has to face more challenges about the TB case detection and treatment among floating population in China. Aim to evaluate the effect of case detection and treatment of the Floating Population TB Control Pilot Project from Global Fund Round Five (GFR5) TB Control Program in China. During October 2006 to September 2008, the pilot project was implemented gradually in 60 counties in Tianjin, Shanghai, Jiangsu, Zhejiang, Fujian, Shandong and Guangdong. All quarterly reports of the pilot project were collected, and these materials were summarized and analyzed. In seven coastal provinces, 19,584 active pulmonary TB (PTB) cases were registered among floating population in 2 years. Among the active PTB cases, 87.2% were 15-45 years old, and 62.8% were male. In second year, 15,629 active PTB cases were registered, and the overall registration rate was 68 per 100,000 people. DOT treatments were provided for 18,125 active PTB cases in 2 years, and overall DOT treatment rate was 92.6%. There were 3,955 active PTB cases registered in first year, and the overall cure rate was 86.0%. Through the implementation of the pilot project, the TB case detection and treatment among floating population have been enhanced in pilot areas of China. The useful experience and results from the pilot project have been being gradually generalized nationally.

  20. Integrated Detection and Prediction of Influenza Activity for Real-Time Surveillance: Algorithm Design.

    Science.gov (United States)

    Spreco, Armin; Eriksson, Olle; Dahlström, Örjan; Cowling, Benjamin John; Timpka, Toomas

    2017-06-15

    Influenza is a viral respiratory disease capable of causing epidemics that represent a threat to communities worldwide. The rapidly growing availability of electronic "big data" from diagnostic and prediagnostic sources in health care and public health settings permits advance of a new generation of methods for local detection and prediction of winter influenza seasons and influenza pandemics. The aim of this study was to present a method for integrated detection and prediction of influenza virus activity in local settings using electronically available surveillance data and to evaluate its performance by retrospective application on authentic data from a Swedish county. An integrated detection and prediction method was formally defined based on a design rationale for influenza detection and prediction methods adapted for local surveillance. The novel method was retrospectively applied on data from the winter influenza season 2008-09 in a Swedish county (population 445,000). Outcome data represented individuals who met a clinical case definition for influenza (based on International Classification of Diseases version 10 [ICD-10] codes) from an electronic health data repository. Information from calls to a telenursing service in the county was used as syndromic data source. The novel integrated detection and prediction method is based on nonmechanistic statistical models and is designed for integration in local health information systems. The method is divided into separate modules for detection and prediction of local influenza virus activity. The function of the detection module is to alert for an upcoming period of increased load of influenza cases on local health care (using influenza-diagnosis data), whereas the function of the prediction module is to predict the timing of the activity peak (using syndromic data) and its intensity (using influenza-diagnosis data). For detection modeling, exponential regression was used based on the assumption that the beginning

  1. Visual-tactile versus radiographic caries detection agreement in caries-active adults.

    Science.gov (United States)

    Ritter, André V; Ramos, Mario D; Astorga, Fernando; Shugars, Daniel A; Bader, James D

    2013-01-01

    The study aims to determine a) the extent of agreement between visual-tactile caries examination (VTE) and radiographic examination (RE) in detecting presumptive caries lesions on occlusal and proximal surfaces of posterior teeth of UNC Xylitol for Adult Caries Trial participants; and b) the additional caries diagnostic yield obtained by adding RE to VTE. Data consisted of surface-level visual-tactile and radiographic classification of disease (cavitated and noncavitated caries lesions) or nondisease (sound surfaces). Participants (n = 114, adults with ≥12 erupted teeth and 1-10 caries lesions) received baseline VTE by a trained and calibrated examiner, and had interproximal radiographs obtained within 7 months before or after the VTE. Radiographs were assessed independently by two trained and calibrated examiners masked with respect to VTE results. The diagnostic threshold was surface-level disease/nondisease status. Kappa statistics provided an estimate of VTE-RE agreement on diseased surfaces. The additional diagnostic yield of the RE over VTE was calculated as the additional lesions detected radiographically as a percentage of the total number of lesions detected by VTE. Four-hundred ninety-four (51 occlusal, 433 proximal) lesions were detected; of these, 81 (2 occlusal, 79 proximal) lesions were detected by both VTE and RE. Kappa statistics were 0.18 (all surfaces), 0.04 (occlusal), and 0.18 (proximal). The additional diagnostic yield was 69 percent (all surfaces), 55 percent (occlusal), and 71 percent (proximal). There is poor agreement between VTE and RE to detect caries in posterior teeth of caries-active adults. However, an RE performed within 7 months of a VTE adds caries diagnostic yield in a clinical trial, especially on proximal surfaces. © 2013 American Association of Public Health Dentistry.

  2. Palladium Nanoparticle Incorporated Porous Activated Carbon: Electrochemical Detection of Toxic Metal Ions.

    Science.gov (United States)

    Veerakumar, Pitchaimani; Veeramani, Vediyappan; Chen, Shen-Ming; Madhu, Rajesh; Liu, Shang-Bin

    2016-01-20

    A facile method has been developed for fabricating selective and sensitive electrochemical sensors for the detection of toxic metal ions, which invokes incorporation of palladium nanoparticles (Pd NPs) on porous activated carbons (PACs). The PACs, which were derived from waste biomass feedstock (fruit peels), possess desirable textural properties and porosities favorable for dispersion of Pd NPs (ca. 3-4 nm) on the graphitic PAC substrate. The Pd/PAC composite materials so fabricated were characterized by a variety of different techniques, such as X-ray diffraction, field-emission transmission electron microscopy, gas physisorption/chemisorption, thermogravimetric analysis, and Raman, Fourier-transform infrared, and X-ray photon spectroscopies. The Pd/PAC-modified glassy carbon electrodes (GCEs) were exploited as electrochemical sensors for the detection of toxic heavy metal ions, viz., Cd(2+), Pb(2+), Cu(2+), and Hg(2+), which showed superior performances for both individual as well as simultaneous detections. For simultaneous detection of Cd(2+), Pb(2+), Cu(2+), and Hg(2+), a linear response in the ion concentration range of 0.5-5.5, 0.5-8.9, 0.5-5.0, and 0.24-7.5 μM, with sensitivity of 66.7, 53.8, 41.1, and 50.3 μA μM(-1) cm(-2), and detection limit of 41, 50, 66, and 54 nM, respectively, was observed. Moreover, the Pd/PAC-modified GCEs also show perspective applications in detection of metal ions in real samples, as illustrated in this study for a milk sample.

  3. [Basic guidelines for detecting sedentarism and recommendations for physical activity in primary care].

    Science.gov (United States)

    Crespo-Salgado, Juan José; Delgado-Martín, José Luis; Blanco-Iglesias, Orlando; Aldecoa-Landesa, Susana

    2015-03-01

    The detection of physical inactivity in adults, using simple and useful tools is primary objective in both public health and in clinical settings, since this risk factor is one of the major causes of non-communicable disease in the world, and is very prevalent in developed societies such as in Spain. Two validated instruments are described that are simple and useful for detecting and/or monitoring physical inactivity in adults: (i)the international physical activity questionnaire in its short version, and (ii)the pedometer to measure the number of steps taken in a day. Increased levels of physical activity are important for the primary prevention of some chronic diseases (coronary heart disease, type2 diabetes, osteoporosis, colon cancer) and to improve the quality of life. Medical personnel must determine the motivation level and the availability of patients and their families to change their behavior towards physical activity. Moderate-intensity physical activities have hardly any contraindications and the risks are few. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  4. Development of a real-time active pipeline integrity detection system

    Science.gov (United States)

    Qing, Xinlin P.; Beard, Shawn; Shen, Shyan Bob; Banerjee, Sourav; Bradley, Ian; Salama, Mamdouh M.; Chang, Fu-Kuo

    2009-11-01

    Utilizing the SMART Layer technology as a basis, a real-time active pipeline integrity detection (RAPID) system is developed for built-in in situ assessment of the health of new and existing pipelines. The RAPID system consists of a sensor network permanently mounted on the host pipeline, portable electronic hardware and diagnostic software. Three moduli, including image display, damage sizing, and corrosion depth, are built into the diagnostic software to help in visualization of the approximate location and the extent of corrosion, and to quantify the corrosion sizing and depth. The main advantages of the RAPID system include: (1) ease of use, (2) ability to provide a well-defined resolution, (3) reliability with self-diagnostic and environmental compensation, and (4) quantified corrosion sizing. To verify the detection capability of the RAPID system, a series of tests have been conducted on a 6.7 m long steel pipe with a diameter of 610 mm and a wall thickness of 7.14 mm with ten different types of corrosion flaws. Test results demonstrated that the depth detection limit could be as low as 0.125 mm for general corrosion with an area of 60 mm × 60 mm under laboratory conditions, while a pinhole with 6.35 mm diameter and 3.5 mm depth can be detected with the given sensor density. Some practical issues for field applications of the RAPID system are also discussed.

  5. Combining Electromyography and Tactile Myography to Improve Hand and Wrist Activity Detection in Prostheses

    Directory of Open Access Journals (Sweden)

    Noémie Jaquier

    2017-10-01

    Full Text Available Despite recent advances in prosthetics and assistive robotics in general, robust simultaneous and proportional control of dexterous prosthetic devices remains an unsolved problem, mainly because of inadequate sensorization. In this paper, we study the application of regression to muscle activity, detected using a flexible tactile sensor recording muscle bulging in the forearm (tactile myography—TMG. The sensor is made of 320 highly sensitive cells organized in an array forming a bracelet. We propose the use of Gaussian process regression to improve the prediction of wrist, hand and single-finger activation, using TMG, surface electromyography (sEMG; the traditional approach in the field, and a combination of the two. We prove the effectiveness of the approach for different levels of activations in a real-time goal-reaching experiment using tactile data. Furthermore, we performed a batch comparison between the different forms of sensorization, using a Gaussian process with different kernel distances.

  6. Multiplex Cathepsin Zymography to Detect Amounts of Active Cathepsins K, L, S, and V.

    Science.gov (United States)

    Platt, Manu O

    2017-01-01

    Cysteine cathepsins are powerful proteases that can degrade other proteins, among which are the extracellular matrix proteins collagen and elastin. Multiplex cathepsin zymography is an assay that can quantify the amount of active cathepsins in a cell or tissue preparation. This method works for measuring the amounts of active cathepsins K, L, S, and V in a cell or tissue preparation without requiring the use of antibodies for specific identification which tremendously reduces cost. This chapter will demonstrate the utility and interpretation of this method with mammalian cells and tissue to quantify amounts of active cathepsins K, L, S, and V without complicating signals of the procathepsin. Multiplex cathepsin zymography has many advantages: (1) it separates cathepsins K, L, S, and V by electrophoretic migration distance, (2) allows visual confirmation of cathepsin identity, (3) does not detect procathepsins, and (4) can be quantified with densitometry.

  7. On-slide detection of enzymatic activities in selected single cells.

    Science.gov (United States)

    Keller, Josephine Geertsen; Tesauro, Cinzia; Coletta, Andrea; Graversen, Astrid Damgaard; Ho, Yi-Ping; Kristensen, Peter; Stougaard, Magnus; Knudsen, Birgitta Ruth

    2017-09-21

    With increasing recognition of the importance in addressing cell-to-cell heterogeneity for the understanding of complex biological systems, there is a growing need for assays capable of single cell analyses. In the current study, we describe the measurement of human topoisomerase I activity in single CD44 positive Caco2 cells specifically captured from a mixed population on glass slides, which were dual functionalized with anti-CD44-antibodies and specific DNA primers. On-slide lysis of captured CD44 positive cells, resulted in the release of human topoisomerase I, allowing the enzyme to circularize a specific linear DNA substrate added to the slides. The generated circles hybridized to the anchored DNA primers and acted as templates for a solid support rolling circle amplification reaction leading to the generation of long tandem repeat products that were detected at the single molecule level in a fluorescent microscope upon hybridization of fluorescent labelled probes. The on-slide detection system was demonstrated to be directly quantitative and specific towards CD44 positive cells. Moreover, it allowed reproducible detection of human topoisomerase I activity in single cells.

  8. In vitro detection and quantification of botulinum neurotoxin type E activity in avian blood

    Science.gov (United States)

    Piazza, Timothy M.; Blehert, David S.; Dunning, F. Mark; Berlowski-Zier, Brenda M.; Zeytin, Fusun N.; Samuel, Michael D.; Tucker, Ward C.

    2011-01-01

    Botulinum neurotoxin serotype E (BoNT/E) outbreaks in the Great Lakes region cause large annual avian mortality events, with an estimated 17,000 bird deaths reported in 2007 alone. During an outbreak investigation, blood collected from bird carcasses is tested for the presence of BoNT/E using the mouse lethality assay. While sensitive, this method is labor-intensive and low throughput and can take up to 7 days to complete. We developed a rapid and sensitive in vitro assay, the BoTest Matrix E assay, that combines immunoprecipitation with high-affinity endopeptidase activity detection by Förster resonance energy transfer (FRET) to rapidly quantify BoNT/E activity in avian blood with detection limits comparable to those of the mouse lethality assay. On the basis of the analysis of archived blood samples (n = 87) collected from bird carcasses during avian mortality investigations, BoTest Matrix E detected picomolar quantities of BoNT/E following a 2-h incubation and femtomolar quantities of BoNT/E following extended incubation (24 h) with 100% diagnostic specificity and 91% diagnostic sensitivity.

  9. A Frequency-Domain Adaptive Matched Filter for Active Sonar Detection.

    Science.gov (United States)

    Zhao, Zhishan; Zhao, Anbang; Hui, Juan; Hou, Baochun; Sotudeh, Reza; Niu, Fang

    2017-07-04

    The most classical detector of active sonar and radar is the matched filter (MF), which is the optimal processor under ideal conditions. Aiming at the problem of active sonar detection, we propose a frequency-domain adaptive matched filter (FDAMF) with the use of a frequency-domain adaptive line enhancer (ALE). The FDAMF is an improved MF. In the simulations in this paper, the signal to noise ratio (SNR) gain of the FDAMF is about 18.6 dB higher than that of the classical MF when the input SNR is -10 dB. In order to improve the performance of the FDAMF with a low input SNR, we propose a pre-processing method, which is called frequency-domain time reversal convolution and interference suppression (TRC-IS). Compared with the classical MF, the FDAMF combined with the TRC-IS method obtains higher SNR gain, a lower detection threshold, and a better receiver operating characteristic (ROC) in the simulations in this paper. The simulation results show that the FDAMF has higher processing gain and better detection performance than the classical MF under ideal conditions. The experimental results indicate that the FDAMF does improve the performance of the MF, and can adapt to actual interference in a way. In addition, the TRC-IS preprocessing method works well in an actual noisy ocean environment.

  10. Rapid Detection of Microorganisms Based on Active and Passive Modes of QCM

    Science.gov (United States)

    Farka, Zdeněk; Kovář, David; Skládal, Petr

    2015-01-01

    Label-free immunosensors are well suited for detection of microorganisms because of their fast response and reasonable sensitivity comparable to infection doses of common pathogens. Active (lever oscillator and frequency counter) and passive (impedance analyzer) modes of quartz crystal microbalance (QCM) were used and compared for rapid detection of three strains of E. coli. Different approaches for antibody immobilization were compared, the immobilization of reduced antibody using Sulfo‐SMCC was most effective achieving the limit of detection (LOD) 8 × 104 CFU·mL−1 in 10 min. For the passive mode, software evaluating impedance characteristics in real-time was developed and used. Almost the same results were achieved using both active and passive modes confirming that the sensor properties are not limited by the frequency evaluation method but mainly by affinity of the antibody. Furthermore, reference measurements were done using surface plasmon resonance. Effect of condition of cells on signal was observed showing that cells ruptured by ultrasonication provided slightly higher signal changes than intact microbes. PMID:25545267

  11. Rapid Detection of Microorganisms Based on Active and Passive Modes of QCM

    Directory of Open Access Journals (Sweden)

    Zdeněk Farka

    2014-12-01

    Full Text Available Label-free immunosensors are well suited for detection of microorganisms because of their fast response and reasonable sensitivity comparable to infection doses of common pathogens. Active (lever oscillator and frequency counter and passive (impedance analyzer modes of quartz crystal microbalance (QCM were used and compared for rapid detection of three strains of E. coli. Different approaches for antibody immobilization were compared, the immobilization of reduced antibody using Sulfo‑SMCC was most effective achieving the limit of detection (LOD 8 × 104 CFU·mL−1 in 10 min. For the passive mode, software evaluating impedance characteristics in real-time was developed and used. Almost the same results were achieved using both active and passive modes confirming that the sensor properties are not limited by the frequency evaluation method but mainly by affinity of the antibody. Furthermore, reference measurements were done using surface plasmon resonance. Effect of condition of cells on signal was observed showing that cells ruptured by ultrasonication provided slightly higher signal changes than intact microbes.

  12. Detection of telomerase activity in saliva from oral squamous cell carcinoma patients.

    Science.gov (United States)

    Zhong, L-P; Chen, G-F; Xu, Z-F; Zhang, X; Ping, F-Y; Zhao, S-F

    2005-07-01

    Tumor markers have been detected in saliva from patients with oral cancers. In order to investigate the expression of telomerase in saliva and its clinical significance. Sixty-two saliva specimens were collected from 32 patients with oral squamous cell carcinoma and 30 normal persons, the telomerase activity was assayed by telomerase PCR-ELISA method. It was detected positively in 75.0% (24/32) of patients with oral squamous cell carcinoma, while it was positive in 6.67% (2/30) of normal persons, the statistical difference was significant with P 0.05, the same to that between the patients with and without lymph nodes metastasis with P > 0.05. The results suggest that the telomerase in saliva could be used as an assistant marker for oral squamous cell carcinoma, however, a larger study is encouraged to confirm the value of judgement on clinical stage and lymph nodes metastasis.

  13. Brain MRI Tumor Detection using Active Contour Model and Local Image Fitting Energy

    Science.gov (United States)

    Nabizadeh, Nooshin; John, Nigel

    2014-03-01

    Automatic abnormality detection in Magnetic Resonance Imaging (MRI) is an important issue in many diagnostic and therapeutic applications. Here an automatic brain tumor detection method is introduced that uses T1-weighted images and K. Zhang et. al.'s active contour model driven by local image fitting (LIF) energy. Local image fitting energy obtains the local image information, which enables the algorithm to segment images with intensity inhomogeneities. Advantage of this method is that the LIF energy functional has less computational complexity than the local binary fitting (LBF) energy functional; moreover, it maintains the sub-pixel accuracy and boundary regularization properties. In Zhang's algorithm, a new level set method based on Gaussian filtering is used to implement the variational formulation, which is not only vigorous to prevent the energy functional from being trapped into local minimum, but also effective in keeping the level set function regular. Experiments show that the proposed method achieves high accuracy brain tumor segmentation results.

  14. Optically Detected Magnetic Resonance and Thermal Activation Spectroscopy Study of Organic Semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang-Hwan [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    Organic electronic materials are a new class of emerging materials. Organic light emitting devices (OLEDs) are the most promising candidates for future flat panel display technologies. The photophysical characterization is the basic research step one must follow to understand this new class of materials and devices. The light emission properties are closely related to the transport properties of these materials. The objective of this dissertation is to probe the relation between transport and photophysical properties of organic semiconductors. The transport characteristics were evaluated by using thermally stimulated current and thermally stimulated luminescence techniques. The photoluminescence detected magnetic resonance and photoluminescence quantum yield studies provide valuable photophysical information on this class of materials. OLEDs are already in the market. However, detailed studies on the degradation mechanisms are still lacking. Since both optically detected magnetic resonance and thermal activation spectroscopy probe long-lived defect-related states in organic semiconductors, the combined study generates new insight on the OLED operation and degradation mechanisms.

  15. Optically Detected Magnetic Resonance and Thermal Activation Spectroscopy Study of Organic Semiconductors

    International Nuclear Information System (INIS)

    Chang-Hwan Kim

    2003-01-01

    Organic electronic materials are a new class of emerging materials. Organic light emitting devices (OLEDs) are the most promising candidates for future flat panel display technologies. The photophysical characterization is the basic research step one must follow to understand this new class of materials and devices. The light emission properties are closely related to the transport properties of these materials. The objective of this dissertation is to probe the relation between transport and photophysical properties of organic semiconductors. The transport characteristics were evaluated by using thermally stimulated current and thermally stimulated luminescence techniques. The photoluminescence detected magnetic resonance and photoluminescence quantum yield studies provide valuable photophysical information on this class of materials. OLEDs are already in the market. However, detailed studies on the degradation mechanisms are still lacking. Since both optically detected magnetic resonance and thermal activation spectroscopy probe long-lived defect-related states in organic semiconductors, the combined study generates new insight on the OLED operation and degradation mechanisms

  16. Frontal Theta Activity Supports Detecting Mismatched Information in Visual Working Memory.

    Science.gov (United States)

    Liang, Tengfei; Hu, Zhonghua; Liu, Qiang

    2017-01-01

    During the comparison stage of visual working memory (VWM) processing, detecting the mismatch between the external sensory input and internal representations is a crucial cognitive ability for human, but the neural mechanism behind it remains largely unclear. The present study investigated the role of frontal theta power in detecting the mismatched information in VWM in a delayed matching task. A control task required to compare two simultaneously presented visual figures was also designed as a contrast to exclude the possibility that frontal theta activity just reflecting the non-memory-related behavioral conflicts. To better characterize the control mechanisms shaped by the frontal theta oscillation in human VWM, colored shapes were adopted as materials while both the task-relevant shape feature and task-irrelevant color feature could be mismatched. We found that the response times of participants were significantly delayed under the relevant- and irrelevant-mismatch conditions in both tasks and the conjunction-mismatch condition in delayed matching task. While our EEG data showed that increased frontal theta power was only observed under the relevant- and conjunction-mismatch conditions in the delayed matching task, but not the control task. These findings suggest that the frontal distributed theta activity observed here reflects the detection of mismatched information during the comparison stage of VWM, rather than the response-related conflicts. Furthermore, it is consistent with the proposal that theta-band oscillation can act as a control mechanism in working memory function so that the target-mismatched information in VWM could be successfully tracked. We also propose a possible processing structure to explain the neural dynamics underlying the mismatch detection process in VWM.

  17. Quantization and training of object detection networks with low-precision weights and activations

    Science.gov (United States)

    Yang, Bo; Liu, Jian; Zhou, Li; Wang, Yun; Chen, Jie

    2018-01-01

    As convolutional neural networks have demonstrated state-of-the-art performance in object recognition and detection, there is a growing need for deploying these systems on resource-constrained mobile platforms. However, the computational burden and energy consumption of inference for these networks are significantly higher than what most low-power devices can afford. To address these limitations, this paper proposes a method to train object detection networks with low-precision weights and activations. The probability density functions of weights and activations of each layer are first directly estimated using piecewise Gaussian models. Then, the optimal quantization intervals and step sizes for each convolution layer are adaptively determined according to the distribution of weights and activations. As the most computationally expensive convolutions can be replaced by effective fixed point operations, the proposed method can drastically reduce computation complexity and memory footprint. Performing on the tiny you only look once (YOLO) and YOLO architectures, the proposed method achieves comparable accuracy to their 32-bit counterparts. As an illustration, the proposed 4-bit and 8-bit quantized versions of the YOLO model achieve a mean average precision of 62.6% and 63.9%, respectively, on the Pascal visual object classes 2012 test dataset. The mAP of the 32-bit full-precision baseline model is 64.0%.

  18. FRET-based detection of isozyme-specific activities of transglutaminases.

    Science.gov (United States)

    Tatsukawa, Hideki; Liu, Hong Hong; Oba, Shota; Kamiya, Noriho; Nakanishi, Yoichi; Hitomi, Kiyotaka

    2017-03-01

    Transglutaminases (TGs) comprise a protein family in which the members catalyze the formation of isopeptide bonds between glutamine and lysine residues in various proteins. Expression studies on its three major members, FXIII, TG1, and TG2, have been performed in a relatively large number of mammalian tissues in comparison with those on the other isozymes. We previously identified a highly reactive substrate peptide, including glutamine, for each isozyme from a phage display library and developed a method for detecting isozyme-specific activities by incorporating a labeled substrate peptide into lysine residues of proteins. Here, we describe genetically encoded Förster resonance energy transfer (FRET)-based probes composed of each fluorescence protein (Cerulean and EVenus) fused with substrate peptides. The probe pairs, designated as Trac-MTG (His-CerΔ11-LQ/EV-K-His) containing linker and substrate peptide sequence for microbial TG (MTG), increased the EVenus:Cerulean fluorescence intensity ratio by more than 1.5-fold. Furthermore, we demonstrated that Trac-TG1 (His-CerΔ11-K5) and Trac-TG2 (His-CerΔ11-T26) containing substrate peptide sequence for mammalian TGs successfully detected the isozyme-specific activity of TG1 and TG2, respectively. In this study, we developed a rapid and convenient experimental system for measuring the isozyme-specific activity of TGs. The application of these probes for analyses in cells and tissues will be helpful for elucidating the physiological and pathological functions of TGs.

  19. Stepwise multiphoton activation fluorescence reveals a new method of melanin detection

    Science.gov (United States)

    Lai, Zhenhua; Kerimo, Josef; Mega, Yair; DiMarzio, Charles A.

    2013-06-01

    The stepwise multiphoton activated fluorescence (SMPAF) of melanin, activated by a continuous-wave mode near infrared (NIR) laser, reveals a broad spectrum extending from the visible spectra to the NIR and has potential application for a low-cost, reliable method of detecting melanin. SMPAF images of melanin in mouse hair and skin are compared with conventional multiphoton fluorescence microscopy and confocal reflectance microscopy (CRM). By combining CRM with SMPAF, we can locate melanin reliably. However, we have the added benefit of eliminating background interference from other components inside mouse hair and skin. The melanin SMPAF signal from the mouse hair is a mixture of a two-photon process and a third-order process. The melanin SMPAF emission spectrum is activated by a 1505.9-nm laser light, and the resulting spectrum has a peak at 960 nm. The discovery of the emission peak may lead to a more energy-efficient method of background-free melanin detection with less photo-bleaching.

  20. Developpement of a photoaffinity probe for the sensitive detection of matrix metallo-protease active forms from complex biological systems

    International Nuclear Information System (INIS)

    Nury, Catherine

    2012-01-01

    A new activity-based probe able to covalently modify the active site of proteases belonging to the matrix metallo-protease family (MMPs) has been developed in this thesis project. The probe was shown to behave as potent inhibitor of several MMPs, with nanomolar Ki values. This probe was also able to modify specifically only the free active site of MMPs, with particular high yields of cross-linking varying from 50 % to 11 %, depending of the MMPs tested. Using radioactivity as means of detection, this probe was able to detect active form of MMPs with a threshold of 1 femto-mole. Applied to the study of bronchoalveolar fluids (BAL) from mice exposed to nanoparticles by a lung aspiration protocol, this probe revealed the presence of the catalytic domain of MMP-12 under its active form, but not in control animals. When used to detect active form of MMPs from extracts obtained from human arteries of patient suffering from atherosclerosis, the probe was not able to detect such MMP active forms. Despite this negative result, the detection of active form of MMP in pathological fluid like BAL has never been reported before this work. Having validated this novel MMP activity-based probe, it will be possible to use it now for detecting MMPs from other pathological fluids or tissues extracts in which MMPs can be good markers of the pathology. (author) [fr

  1. Minimum detectable activities for natural radionuclides for IRIS-XP airborne gamma-spectrometer

    International Nuclear Information System (INIS)

    Ohera, Marcel; Sladek, Petr

    2009-01-01

    To subtract the 90 Sr background in the helicopter (the 90 Sr source is used as a freezing deposit indicator in Mi-17 helicopters), a spectrum at the altitude of more than 500 metre altitude above the ground for 10 minutes was acquired. The spectra at 50, 100 and 150 m altitude were corrected for the aircraft and the cosmics, stripping and height attenuation in K, U and Th peak windows. For IRIS-XP, better results have been obtained than presented so far. The new calculated minimum detectable activities (MDAs) are 114 Bq/kg for 40 K, 16 Bq/kg for 238 U and 8 Bq/kg for 232 Th at 95% confidence interval for 1 second spectra at 100 m altitude. This work deals with counting statistics and the estimate of the MDAs for natural radionuclides for the IRIS-XP airborne gamma-ray spectrometer (4 x 4 litre NaI(Tl)) produced by PICO Envirotec, Inc. in Toronto, Canada. The detection sensitivities (MDA) for 4 x 4 NaI(Tl) crystals at the altitude of 90 m presented by Pico Envirotec, Inc. are too high compared with the detection sensitivities presented by other airborne gamma-ray spectrometer producers. This was the reason why to calculate and verify the MDA for IRIS-XP. Firstly, the minimum detectable activities for IRIS-XP for 4 x 4 litre NaI(Tl) crystals were determined based on the data acquired on the calibration pads at the Holland Landing Airport in Toronto, Canada to test the method of calculation used. This method on calibration pads provides all available window sensitivities, stripping factors and counts in the natural radionuclide windows to verify the computing method. Secondly, the MDAs under the real flight conditions were also estimated for the IRIS-XP (4 x 4 litre NaI(Tl) crystals) which was delivered to the Czech Armed Forces. The MDAs were calculated based on the data acquired during the tests at the Military Training Area in Vyskov, Czech Republic. The data was collected at three different altitudes (50 m, 100 m and 150 m) when the Mi-17 helicopter with IRIS

  2. An α-activity imaging monitor system for rapidly detecting PU contamination

    International Nuclear Information System (INIS)

    Iida, T.; Ikebe, Y.; Nishiya, T.; Ogura, T.; Nomura, T.

    1992-01-01

    A new type of α-activity imaging monitor system was constructed for rapidly obtaining the position profile of Pu contamination on filter paper. The system consists of a detector head, and image intensifier, a low-lag vidicon and an image processor. When the integrated image is taken with 10 min., PuO 2 particles more than 0.03 Bq and Pu (NO 3 ) 4 particles more than 0.13 Bq can be rapidly detected by spot separation processing. (author)

  3. Evaluation and Uncertainty of a New Method to Detect Suspected Nuclear and WMD Activity: Project Report

    Energy Technology Data Exchange (ETDEWEB)

    Kurzeja, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Werth, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Buckley, R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-29

    The Atmospheric Technology Group at SRNL developed a new method to detect signals from Weapons of Mass Destruction (WMD) activities in a time series of chemical measurements at a downwind location. This method was tested with radioxenon measured in Russia and Japan after the 2013 underground test in North Korea. This LDRD calculated the uncertainty in the method with the measured data and also for a case with the signal reduced to 1/10 its measured value. The research showed that the uncertainty in the calculated probability of origin from the NK test site was small enough to confirm the test. The method was also wellbehaved for small signal strengths.

  4. Power Spectral Deviation-Based Voice Activity Detection Incorporating Teager Energy for Speech Enhancement

    Directory of Open Access Journals (Sweden)

    Sang-Kyun Kim

    2016-07-01

    Full Text Available In this paper, we propose a robust voice activity detection (VAD algorithm to effectively distinguish speech from non-speech in various noisy environments. The proposed VAD utilizes power spectral deviation (PSD, using Teager energy (TE to provide a better representation of the PSD, resulting in improved decision performance for speech segments. In addition, the TE-based likelihood ratio and speech absence probability are derived in each frame to modify the PSD for further VAD. We evaluate the performance of the proposed VAD algorithm by objective testing in various environments and obtain better results that those attained by of the conventional methods.

  5. A hierarchical framework approach for voice activity detection and speech enhancement.

    Science.gov (United States)

    Zhang, Yan; Tang, Zhen-min; Li, Yan-ping; Luo, Yang

    2014-01-01

    Accurate and effective voice activity detection (VAD) is a fundamental step for robust speech or speaker recognition. In this study, we proposed a hierarchical framework approach for VAD and speech enhancement. The modified Wiener filter (MWF) approach is utilized for noise reduction in the speech enhancement block. For the feature selection and voting block, several discriminating features were employed in a voting paradigm for the consideration of reliability and discriminative power. Effectiveness of the proposed approach is compared and evaluated to other VAD techniques by using two well-known databases, namely, TIMIT database and NOISEX-92 database. Experimental results show that the proposed method performs well under a variety of noisy conditions.

  6. Methods of expressing and detecting activity of expansin in plant cells

    Energy Technology Data Exchange (ETDEWEB)

    Hood, Elizabeth E.; Yoon, Sangwoong

    2017-10-10

    A method of expressing heterologous expansin in a plant cell is provided where a nucleic acid molecule encoding expansin is introduced into the plant cell and in an embodiment is operably linked to a promoter preferentially expressing in the seed tissue of the plant, and in another embodiment is linked to a promoter preferentially expressing in the embryo tissue of the seed. An embodiment provides the nucleic acid molecule is operably linked to a second nucleic acid molecule that directs expression to the endoplasmic reticulum, vacuole or cell wall. Plants and plant parts expressing expansin are provided. An assay for detection of expansin activity is also provided.

  7. Nasopharyngeal Infection of Mice with Streptococcus pyogenes and In Vivo Detection of Superantigen Activity.

    Science.gov (United States)

    Zeppa, Joseph J; Wakabayashi, Adrienne T; Kasper, Katherine J; Xu, Stacey X; Haeryfar, S M Mansour; McCormick, John K

    2016-01-01

    Streptococcus pyogenes is a globally prominent human-specific pathogen that is responsible for an enormous burden of infectious disease. Despite intensive experimental efforts to understand the molecular correlates that contribute to invasive infections, there has been less focus on S. pyogenes carriage and local infection of the nasopharynx. This chapter describes an acute nasopharyngeal infection model in mice that is utilized in our laboratory to study the role of superantigen toxins in the biology of S. pyogenes. We also describe a method to detect superantigen-specific T cell activation in vivo.

  8. Selection and application of ssDNA aptamers to detect active TB from sputum samples

    CSIR Research Space (South Africa)

    Rotherham, LS

    2012-10-01

    Full Text Available and Application of ssDNA Aptamers to Detect Active TB from Sputum Samples Lia S. Rotherham1,2, Charlotte Maserumule1,3, Keertan Dheda3, Jacques Theron2, Makobetsa Khati1,3* 1 Emerging Health Technologies Platform, Council for Scientific and Industrial Research...?50 times less than those for producing antibodies [25]. Aptamers have been raised against a wide variety of targets, from small human molecules and viral proteins to whole microorganisms [26]. Single-stranded DNA (ssDNA) aptamers are usually used...

  9. The capsule endoscopy "suspected blood indicator" (SBI) for detection of active small bowel bleeding: no active bleeding in case of negative SBI.

    Science.gov (United States)

    Tal, Andrea Oliver; Filmann, Natalie; Makhlin, Konstantin; Hausmann, Johannes; Friedrich-Rust, Mireen; Herrmann, Eva; Zeuzem, Stefan; Albert, Jörg G

    2014-09-01

    Capsule endoscopy (CE) is the gold standard to diagnose small bowel bleeding. The "suspected blood indicator" (SBI) offers an automated detection of active small bowel bleeding but validity of this technique is unknown. The objective was to analyze specificity and sensitivity of the SBI using the second small bowel capsule generation for the detection of active bleeding. This is a retrospective analysis of all patients (199) who attended our clinic for CE from June 2008 through March 2013. The second-generation PillCam SB 2 capsule was used for detection of (1) luminal blood content and (2) potentially responsible small bowel lesions. The findings of an independent investigator were correlated to SBI findings and a number of SBI markings were analyzed by a receiver operating characteristic (ROC). In 157/199 cases, no sign of active bleeding or altered blood was detected. One hundred and thirty-seven of these 157 cases provided at least one SBI marking and a mean of 18.4 positive SBI markings per record were found. In 20 cases, neither SBI nor the human investigator detected abnormalities. Thirteen patients showed investigator-detected minor bleeding with mean SBI findings of 36 positive screenshots per record. When major bleeding was diagnosed by the investigator (n = 29), SBI detected a mean of 46.6 SBI-positive markings. SBI turned positive in 179 patients, whereas the investigator detected active bleeding in 42 cases. All patients with active bleeding were detected by SBI (sensitivity 100%, specificity 13%). ROC analysis revealed 51.0 SBI markings being the optimal cutoff for active versus no bleeding (sensitivity 79.1%, specificity 90.4%, misclassification of 15.3%). The new SBI software is a reliable tool to exclude active bleeding and/or major lesions but analysis of the CE video by a trained investigator is still important for the detection of lesions responsible for past bleeding.

  10. Rapid screening for Chlamydia trachomatis infection by detecting α-mannosidase activity in urogenital tract specimens.

    Science.gov (United States)

    Wang, Ze-yu; Fu, Guang-yu; Wang, Shan-mei; Qin, Dong-chun; Wang, Zhong-quan; Cui, Jing

    2013-01-24

    Chlamydia trachomatis may cause multiple different urogenital tract disorders, but current non-culture assays for rapid screening of C. trachomatis typically use immunochromatography-based methods. We established another new rapid non-culture method for detection of C. trachomatis based on the measurement of α-mannosidase enzymatic activity in urogenital tract specimens. To evaluate the performance of this method, α-mannosidase activities of C. trachomatis serotype D strain 、 and 29 standard strains related to clinical urogenital pathogens were investigated. Furthermore, 553 urogenital tract specimens were used for clinical assays via cell culture method and ligase chain reaction method (LCR), adopting an expanded gold standard. Only C. trachomatis was positive for α-mannosidase activity among different types of microbes tested in the research. When prostate fluid specimens, which have some interfering activity, were excluded, the sensitivity and specificity of the enzymatic method were 91.8% (78/85) and 98.3% (409/416), respectively. There were no significant differences (P > 0.05). These results showed that α-mannosidase activity could be utilised as a screening marker of C. trachomatis infection.

  11. Rapid screening for Chlamydia trachomatis infection by detecting α-mannosidase activity in urogenital tract specimens

    Directory of Open Access Journals (Sweden)

    Wang Ze-yu

    2013-01-01

    Full Text Available Abstract Background Chlamydia trachomatis may cause multiple different urogenital tract disorders, but current non-culture assays for rapid screening of C. trachomatis typically use immunochromatography-based methods. We established another new rapid non-culture method for detection of C. trachomatis based on the measurement of α-mannosidase enzymatic activity in urogenital tract specimens. Method To evaluate the performance of this method, α-mannosidase activities of C. trachomatis serotype D strain 、 and 29 standard strains related to clinical urogenital pathogens were investigated. Furthermore, 553 urogenital tract specimens were used for clinical assays via cell culture method and ligase chain reaction method (LCR, adopting an expanded gold standard. Results Only C. trachomatis was positive for α-mannosidase activity among different types of microbes tested in the research. When prostate fluid specimens, which have some interfering activity, were excluded, the sensitivity and specificity of the enzymatic method were 91.8% (78/85 and 98.3% (409/416, respectively. There were no significant differences (P > 0.05. Conclusions These results showed that α-mannosidase activity could be utilised as a screening marker of C. trachomatis infection.

  12. Photoacoustic imaging to detect rat brain activation after cocaine hydrochloride injection

    Science.gov (United States)

    Jo, Janggun; Yang, Xinmai

    2011-03-01

    Photoacoustic imaging (PAI) was employed to detect small animal brain activation after the administration of cocaine hydrochloride. Sprague Dawley rats were injected with different concentrations (2.5, 3.0, and 5.0 mg per kg body) of cocaine hydrochloride in saline solution through tail veins. The brain functional response to the injection was monitored by photoacoustic tomography (PAT) system with horizontal scanning of cerebral cortex of rat brain. Photoacoustic microscopy (PAM) was also used for coronal view images. The modified PAT system used multiple ultrasonic detectors to reduce the scanning time and maintain a good signal-to-noise ratio (SNR). The measured photoacoustic signal changes confirmed that cocaine hydrochloride injection excited high blood volume in brain. This result shows PAI can be used to monitor drug abuse-induced brain activation.

  13. Comparison of two methods of voice activity detection in field studies.

    Science.gov (United States)

    Lindstrom, Fredric; Ren, Keni; Li, Haibo; Waye, Kerstin Persson

    2009-12-01

    To evaluate and compare the performance of 2 methods of voice activity detection (neck-attached accelerometer vs. binaural recordings) in field studies in environments where voice activity normally occurs. A group of 11 healthy adults wore recording equipment during their lunch break. We used binary classification to analyze the results from the 2 methods. The output was compared to a gold standard, obtained through listening tests, and the probability for sensitivity (Ps) and false positive (Pf) was rated. The binary classifiers were set for consistent sensitivity of 99%; thus, the lower false positive rate would indicate the method with the better performance. The neck-attached accelerometer (Pf = 0.5%) performed significantly (p voice assessments in environments where people are speaking in close proximity to each other and where the signal-to-noise ratio is moderate to low.

  14. Detection of Cardiopulmonary Activity and Related Abnormal Events Using Microsoft Kinect Sensor

    Directory of Open Access Journals (Sweden)

    Ali Al-Naji

    2018-03-01

    Full Text Available Monitoring of cardiopulmonary activity is a challenge when attempted under adverse conditions, including different sleeping postures, environmental settings, and an unclear region of interest (ROI. This study proposes an efficient remote imaging system based on a Microsoft Kinect v2 sensor for the observation of cardiopulmonary-signal-and-detection-related abnormal cardiopulmonary events (e.g., tachycardia, bradycardia, tachypnea, bradypnea, and central apnoea in many possible sleeping postures within varying environmental settings including in total darkness and whether the subject is covered by a blanket or not. The proposed system extracts the signal from the abdominal-thoracic region where cardiopulmonary activity is most pronounced, using a real-time image sequence captured by Kinect v2 sensor. The proposed system shows promising results in any sleep posture, regardless of illumination conditions and unclear ROI even in the presence of a blanket, whilst being reliable, safe, and cost-effective.

  15. First Detection and Characterization of Streptococcus dentapri from Caries Active Subject.

    Science.gov (United States)

    Salman, Hamzah Abdulrahman; Kumar, R Senthil; Babu, N Chaitanya; Imran, Khalid

    2017-07-01

    Mutans streptococci (MS) are a group of oral bacteria generally regarded as the principal agents in the pathogenesis of dental caries. The study aimed was characterize S. dentapri based on phylogenetic analysis and phenotypic methods from Caries Active Subject. While sequencing MS species which were isolated from 65 caries active subjects, one strain of S. dentapri was detected. Dental plaque samples were processed and cultured on mitis salivarius bacitracin agar. S. dentapri was characterized using phylogenetic analysis, colony morphology characterization and biotyping. Among the study population, one strain designated as H14 was identified as S. dentapri by 16S rDNA sequencing. Morphologically, S. dentapri could not differentiate from other species of MS. S. dentapri H14 demonstrated biotype II biochemical characteristics of MS. The phylogenetic analysis showed S. dentapri is closely related to S. macacae . The study concludes that S. dentapri can inhabit the human oral cavity and therefore further investigations are warranted to determine its role in caries.

  16. Diagnostic methods of detecting defects within the material with the use of active infrared thermovision

    Directory of Open Access Journals (Sweden)

    Grochalski Karol

    2017-01-01

    Full Text Available Article presents the methods of detecting defects within material with the use of active infrared thermovision. During the study ABS and PVC samples were used inside which internal structure defects and defects of glue conjunction between components were modeled. During combining composite materials with the use of glue joints, there is a problem with homogenous distribution of the glue layer on the surface of an element, which results in the creation of defects in joint structure and the decline of active surface of adhesion forces on the combined materials. It is then necessary to control the quality of the conjunction between the glued surfaces. The use of non-contact diagnostic methods allows to analyze a larger surface which conditions in more efficient quality control process. In the study, external heat excitation was used - optical excitation with periodic variable signal (LockIn method and unit step excitation (Pulse method. The methods of analysis of the obtained thermograms are presented.

  17. Thalamocortical network activity enables chronic tic detection in humans with Tourette syndrome

    Directory of Open Access Journals (Sweden)

    Jonathan B. Shute

    2016-01-01

    Full Text Available Tourette syndrome (TS is a neuropsychiatric disorder characterized by multiple motor and vocal tics. Deep brain stimulation (DBS is an emerging therapy for severe cases of TS. We studied two patients with TS implanted with bilateral Medtronic Activa PC + S DBS devices, capable of chronic recordings, with depth leads in the thalamic centromedian–parafascicular complex (CM-PF and subdural strips over the precentral gyrus. Low-frequency (1–10 Hz CM-PF activity was observed during tics, as well as modulations in beta rhythms over the motor cortex. Tics were divided into three categories: long complex, complex, and simple. Long complex tics, tics involving multiple body regions and lasting longer than 5 s, were concurrent with a highly detectable thalamocortical signature (average recall [sensitivity] 88.6%, average precision 96.3%. Complex tics were detected with an average recall of 63.9% and precision of 36.6% and simple tics an average recall of 39.3% and precision of 37.9%. The detections were determined using data from both patients.

  18. Detecting seismic activity with a covariance matrix analysis of data recorded on seismic arrays

    Science.gov (United States)

    Seydoux, L.; Shapiro, N. M.; de Rosny, J.; Brenguier, F.; Landès, M.

    2016-03-01

    Modern seismic networks are recording the ground motion continuously at the Earth's surface, providing dense spatial samples of the seismic wavefield. The aim of our study is to analyse these records with statistical array-based approaches to identify coherent time-series as a function of time and frequency. Using ideas mainly brought from the random matrix theory, we analyse the spatial coherence of the seismic wavefield from the width of the covariance matrix eigenvalue distribution. We propose a robust detection method that could be used for the analysis of weak and emergent signals embedded in background noise, such as the volcanic or tectonic tremors and local microseismicity, without any prior knowledge about the studied wavefields. We apply our algorithm to the records of the seismic monitoring network of the Piton de la Fournaise volcano located at La Réunion Island and composed of 21 receivers with an aperture of ˜15 km. This array recorded many teleseismic earthquakes as well as seismovolcanic events during the year 2010. We show that the analysis of the wavefield at frequencies smaller than ˜0.1 Hz results in detection of the majority of teleseismic events from the Global Centroid Moment Tensor database. The seismic activity related to the Piton de la Fournaise volcano is well detected at frequencies above 1 Hz.

  19. Active sensing and damage detection using piezoelectric zinc oxide-based nanocomposites.

    Science.gov (United States)

    Meyers, Frederick N; Loh, Kenneth J; Dodds, John S; Baltazar, Arturo

    2013-05-10

    This study investigated the design and performance of piezoelectric nanocomposite-based interdigitated transducers (IDTs) for active sensing and damage detection. First, thin films that are highly piezoelectric and mechanically flexible were designed by embedding zinc oxide (ZnO) nanoparticles in a poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) piezo-polymer matrix. Second, the suspended nanoparticle solutions were then spin coated onto patterned comb electrodes to fabricate the IDTs. The films were then poled to align their electric domains and to increase their permanent piezoelectricity. Upon IDT fabrication, its sensing and actuation of Lamb waves on an aluminum pipe was validated. These results were also compared to data obtained from commercial Macro Fiber Composite IDT transducers. In the last phase of this work, damage detection was demonstrated by mounting these nanocomposite sensors and actuators (using a pitch-catch setup) onto an aluminum pipe and plate. Damage was simulated by tightening a band clamp around the pipe and by drilling holes in the plate. A damage index calculation was used to compare results corresponding to different levels of damage applied to the plate (i.e., different drilled hole depths), and good correlation was observed. Thus, ZnO/PVDF-TrFE transducers were shown to have the potential for use as piezoelectric transducers for structural health monitoring and damage detection.

  20. Rapid Detection of Thrombin and Other Protease Activity Directly in Whole Blood

    Science.gov (United States)

    Yu, Johnson Chung Sing

    Thrombin is a serine protease that plays a key role in the clotting cascade to promote hemostasis following injury to the endothelium. From a clinical diagnostic perspective, in-vivo thrombin activity is linked to various blood clotting disorders, as well as cardiovascular disease (DVT, arteriosclerosis, etc). Thus, the ability to rapidly measure protease activity directly in whole blood will provide important new diagnostics, and clinical researchers with a powerful tool to further elucidate the relationship between circulating protease levels and disease. The ultimate goal is to design novel point of care (POC) diagnostic devices that are capable of monitoring protease activities directly in whole blood and biological sample. A charge-changing substrate specific to the thrombin enzyme was engineered and its functionality was confirmed by a series of experiments. This led to the preliminary design, construction, and testing of two device platforms deemed fully functional for the electrophoretic separation and focusing of charged peptide fragments. The concept of using the existing charge-changing substrate platform for bacterial protease detection was also investigated. Certain strains of E coli are associated with severe symptoms such as abdominal cramps, bloody diarrhea, and vomiting. The OmpT protease is expressed on the outer membrane of E coli and plays a role in the cleavage of antimicrobial peptides, the degradation of recombinant heterologous proteins, and the activation of plasminogen in the host. Thus, a synthetic peptide substrate specific to the OmpT protease was designed and modeled for the purpose of detecting E coli in biological sample.

  1. SU-G-201-03: Automation of High Dose Rate Brachytherapy Quality Assurance: Development of a Radioluminescent Detection System for Simultaneous Detection of Activity, Timing, and Positioning

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, C; Xing, L; Fahimian, B [Stanford University, Stanford, CA (United States)

    2016-06-15

    Purpose: Accuracy of positioning, timing and activity is of critical importance for High Dose Rate (HDR) brachytherapy delivery. Respective measurements via film autoradiography, stop-watches and well chambers can be cumbersome, crude or lack dynamic source evaluation capabilities. To address such limitations, a single device radioluminescent detection system enabling automated real-time quantification of activity, position and timing accuracy is presented and experimentally evaluated. Methods: A radioluminescent sheet was fabricated by mixing Gd?O?S:Tb with PDMS and incorporated into a 3D printed device where it was fixated below a CMOS digital camera. An Ir-192 HDR source (VS2000, VariSource iX) with an effective active length of 5 mm was introduced using a 17-gauge stainless steel needle below the sheet. Pixel intensity values for determining activity were taken from an ROI centered on the source location. A calibration curve relating intensity values to activity was generated and used to evaluate automated activity determination with data gathered over 6 weeks. Positioning measurements were performed by integrating images for an entire delivery and fitting peaks to the resulting profile. Timing measurements were performed by evaluating source location and timestamps from individual images. Results: Average predicted activity error over 6 weeks was .35 ± .5%. The distance between four dwell positions was determined by the automated system to be 1.99 ± .02 cm. The result from autoradiography was 2.00 ± .03 cm. The system achieved a time resolution of 10 msec and determined the dwell time to be 1.01 sec ± .02 sec. Conclusion: The system was able to successfully perform automated detection of activity, positioning and timing concurrently under a single setup. Relative to radiochromic and radiographic film-based autoradiography, which can only provide a static evaluation positioning, optical detection of temporary radiation induced luminescence enables dynamic

  2. Auto-deleting brain machine interface: Error detection using spiking neural activity in the motor cortex.

    Science.gov (United States)

    Even-Chen, Nir; Stavisky, Sergey D; Kao, Jonathan C; Ryu, Stephen I; Shenoy, Krishna V

    2015-01-01

    Brain machine interfaces (BMIs) aim to assist people with paralysis by increasing their independence and ability to communicate, e.g., by using a cursor-based virtual keyboard. Current BMI clinical trials are hampered by modest performance that causes selection of wrong characters (errors) and thus reduces achieved typing rate. If it were possible to detect these errors without explicit knowledge of the task goal, this could be used to automatically "undo" wrong selections or even prevent upcoming wrong selections. We decoded imminent or recent errors during closed-loop BMI control from intracortical spiking neural activity. In our experiment, a non-human primate controlled a neurally-driven BMI cursor to acquire targets on a grid, which simulates a virtual keyboard. In offline analyses of this closed-loop BMI control data, we identified motor cortical neural signals indicative of task error occurrence. We were able to detect task outcomes (97% accuracy) and even predict upcoming task outcomes (86% accuracy) using neural activity alone. This novel strategy may help increase the performance and clinical viability of BMIs.

  3. Analysis of microseismic activity detected by the WIZARD array, Alpine Fault, New Zealand

    Science.gov (United States)

    Feenstra, J. P.; Roecker, S. W.; Thurber, C. H.; Lord, N.; O'Brien, G.; Pesicek, J. D.; Townend, J.; Bannister, S. C.

    2012-12-01

    A primary goal for the UW-Madison-RPI WIZARD array is the characterization of background seismicity around the Deep Fault Drilling Project (DFDP) site on the Alpine Fault, South Island, New Zealand. The WIZARD array consists of 20 stations, half broadband, deployed for a planned 2-year period around the Whataroa Valley DFDP-2 drill site. Two neighboring arrays, SAMBA (Victoria University of Wellington) to the southwest and ALFA'12 (GNS Science) to the northeast, along with several GeoNet permanent stations, provide broad coverage of the region. The earthquakes that are detected will (1) help to define the geometry of the Alpine Fault and other active faults at depth, (2) provide data for seismic imaging, focal mechanisms, and shear-wave splitting analysis, and (3) enable the assessment of possible changes in seismic activity induced by future fault zone drilling. We are currently analyzing data from the first 2 months of the deployment. Dozens of nearby earthquakes (S-P time of up to a few seconds) have been detected, far more than are in the New Zealand GeoNET catalog. This is expected because the magnitude completion level of the GeoNet seismometer network is around 2.5 in the Whataroa region, due to a relatively sparse station coverage. In this presentation, we report on earthquake location results for 8 months of WIZARD data, along with focal mechanisms for selected larger events.

  4. Neutron activation techniques in the detection and measurement of environmental pollutants

    International Nuclear Information System (INIS)

    Spyrou, N.M.; Maheswaran, P.; Nagy, K.; Oezek, F.

    1976-01-01

    The Medical and Environmental Group at the University of Surrey has been involved for several years in the development and application of nuclear activation techniques to biomedical and environmental problems. One such project has been a study of air pollution in the city of Guildford, which requires a routine but quick analytical process for the detection of trace elements in the atmosphere in order to handle data with limited resources and manpower. The proposed method comprises cyclic irradiation and counting, followed by further counting on a low-energy photon detector and a Ge(Li) detector. The scheme concentrates on the measurement of short-lived isotopes. In order to test its efficacy it is compared with conventional activation experiments for irradiation times of 1 min, 10 min and 60 min; various types of filter papers and membranes, used for collection of the samples, are analysed under these conditions. The paper illustrates this comparison by analysis of NBS Standard Reference Material 1571 (Orchard Leaves) on Whatman grade 1 filter paper. The analysis of a typical Guildford sample is also shown. The technique enhances the detection of 38 Clsup(m)(0.74 s), 207 Pbsup(m)(0.8 s), 20 F(11.56 s), 77 Sesup(m)(17.5 s) and 110 Ag(24.4 s). (author)

  5. Speech activity detection for the automated speaker recognition system of critical use

    Directory of Open Access Journals (Sweden)

    M. M. Bykov

    2017-06-01

    Full Text Available In the article, the authors developed a method for detecting speech activity for an automated system for recognizing critical use of speeches with wavelet parameterization of speech signal and classification at intervals of “language”/“pause” using a curvilinear neural network. The method of wavelet-parametrization proposed by the authors allows choosing the optimal parameters of wavelet transformation in accordance with the user-specified error of presentation of speech signal. Also, the method allows estimating the loss of information depending on the selected parameters of continuous wavelet transformation (NPP, which allowed to reduce the number of scalable coefficients of the LVP of the speech signal in order of magnitude with the allowable degree of distortion of the local spectrum of the LVP. An algorithm for detecting speech activity with a curvilinear neural network classifier is also proposed, which shows the high quality of segmentation of speech signals at intervals "language" / "pause" and is resistant to the presence in the speech signal of narrowband noise and technogenic noise due to the inherent properties of the curvilinear neural network.

  6. Detections of Yersinia pestis East of the Known Distribution of Active Plague in the United States.

    Science.gov (United States)

    Mize, Erica L; Britten, Hugh B

    2016-02-01

    We examined fleas collected from black-tailed prairie dog (Cynomys ludovicianus) burrows from 2009 through 2011 in five national park units east of the known distribution of active plague across the northern Great Plains for the presence of Yersinia pestis. Across all national park units, Oropsylla tuberculata and Oropsylla hirsuta were the most common fleas collected from prairie dog burrows, 42.4% and 56.9%, respectively, of the 3964 fleas collected from burrow swabbing. Using a nested PCR assay, we detected 200 Y. pestis-positive fleas from 3117 assays. In total, 6.4% of assayed fleas were Y. pestis positive and 13.9% of prairie dog burrows swabbed contained Y. pestis-positive fleas. Evidence of the presence of Y. pestis was observed at all national park units except Devils Tower National Monument in Wyoming. We detected the presence of Y. pestis without large die-offs, i.e., enzootic sylvatic plague, east of the known distribution of active plague and near the eastern edge of the present distribution of black-tailed prairie dogs. This study, in combination with previous work suggests that sylvatic plague likely occurs across the range of black-tailed prairie dogs and should now be treated as endemic across this range.

  7. Detection of epileptiform activity in EEG signals based on time-frequency and nonlinear analysis

    Directory of Open Access Journals (Sweden)

    Dragoljub eGajic

    2015-03-01

    Full Text Available We present a new technique for detection of epileptiform activity in EEG signals. After preprocessing of EEG signals we extract representative features in time, frequency and time-frequency domain as well as using nonlinear analysis. The features are extracted in a few frequency sub-bands of clinical interest since these sub-bands showed much better discriminatory characteristics compared with the whole frequency band. Then we optimally reduce the dimension of feature space to two using scatter matrices. A decision about the presence of epileptiform activity in EEG signals is made by quadratic classifiers designed in the reduced two-dimensional feature space. The accuracy of the technique was tested on three sets of electroencephalographic (EEG signals recorded at the University Hospital Bonn: surface EEG signals from healthy volunteers, intracranial EEG signals from the epilepsy patients during the seizure free interval from within the seizure focus and intracranial EEG signals of epileptic seizures also from within the seizure focus. An overall detection accuracy of 98.7% was achieved.

  8. Methylene blue not ferrocene: Optimal reporters for electrochemical detection of protease activity.

    Science.gov (United States)

    González-Fernández, Eva; Avlonitis, Nicolaos; Murray, Alan F; Mount, Andrew R; Bradley, Mark

    2016-10-15

    Electrochemical peptide-based biosensors are attracting significant attention for the detection and analysis of proteins. Here we report the optimisation and evaluation of an electrochemical biosensor for the detection of protease activity using self-assembled monolayers (SAMs) on gold surfaces, using trypsin as a model protease. The principle of detection was the specific proteolytic cleavage of redox-tagged peptides by trypsin, which causes the release of the redox reporter, resulting in a decrease of the peak current as measured by square wave voltammetry. A systematic enhancement of detection was achieved through optimisation of the properties of the redox-tagged peptide; this included for the first time a side-by-side study of the applicability of two of the most commonly applied redox reporters used for developing electrochemical biosensors, ferrocene and methylene blue, along with the effect of changing both the nature of the spacer and the composition of the SAM. Methylene blue-tagged peptides combined with a polyethylene-glycol (PEG) based spacer were shown to be the best platform for trypsin detection, leading to the highest fidelity signals (characterised by the highest sensitivity (signal gain) and a much more stable background than that registered when using ferrocene as a reporter). A ternary SAM (T-SAM) configuration, which included a PEG-based dithiol, minimised the non-specific adsorption of other proteins and was sensitive towards trypsin in the clinically relevant range, with a Limit of Detection (LoD) of 250pM. Kinetic analysis of the electrochemical response with time showed a good fit to a Michaelis-Menten surface cleavage model, enabling the extraction of values for kcat and KM. Fitting to this model enabled quantitative determination of the solution concentration of trypsin across the entire measurement range. Studies using an enzyme inhibitor and a range of real world possible interferents demonstrated a selective response to trypsin

  9. Underwater Cylindrical Object Detection Using the Spectral Features of Active Sonar Signals with Logistic Regression Models

    Directory of Open Access Journals (Sweden)

    Yoojeong Seo

    2018-01-01

    Full Text Available The issue of detecting objects bottoming on the sea floor is significant in various fields including civilian and military areas. The objective of this study is to investigate the logistic regression model to discriminate the target from the clutter and to verify the possibility of applying the model trained by the simulated data generated by the mathematical model to the real experimental data because it is not easy to obtain sufficient data in the underwater field. In the first stage of this study, when the clutter signal energy is so strong that the detection of a target is difficult, the logistic regression model is employed to distinguish the strong clutter signal and the target signal. Previous studies have found that if the clutter energy is larger, false detection occurs even for the various existing detection schemes. For this reason, the discrete Fourier transform (DFT magnitude spectrum of acoustic signals received by active sonar is applied to train the model to distinguish whether the received signal contains a target signal or not. The goodness of fit of the model is verified in terms of receiver operation characteristic (ROC, area under ROC curve (AUC, and classification table. The detection performance of the proposed model is evaluated in terms of detection rate according to target to clutter ratio (TCR. Furthermore, the real experimental data are employed to test the proposed approach. When using the experimental data to test the model, the logistic regression model is trained by the simulated data that are generated based on the mathematical model for the backscattering of the cylindrical object. The mathematical model is developed according to the size of the cylinder used in the experiment. Since the information on the experimental environment including the sound speed, the sediment type and such is not available, once simulated data are generated under various conditions, valid simulated data are selected using 70% of the

  10. Electrochemical detection of specific DNA and respiratory activity of Escherichia coli

    International Nuclear Information System (INIS)

    Yamanaka, Keiichiro; Ikeuchi, Tomohiko; Saito, Masato; Nagatani, Naoki; Tamiya, Eiichi

    2012-01-01

    We present two rapid and simplified detection methods for Escherichia coli involving the use of a hand-held potentiostat and a disposable screen-printed carbon electrode. E. coli is one of the indicator organisms used to access for food safety. Commonly, microbiological culture techniques take more than one day to yield results and therefore, a simple, cost-effective, in situ detection system is required for testing food safety. This report describes two complementary techniques for high- and low-sensitivity detection of E. coli. High-sensitivity detection relies upon quantification of DNA amplification by using polymerase chain reaction (PCR), while the simplified, low-sensitivity detection can be obtained through measurement of oxygen consumption due to respiration; importantly, both techniques utilize the same type of electrode. The former entails mixing the PCR mixture with Hoechst, an electro-active DNA intercalator, and then, measuring the oxidation current. Binding of Hoechst molecules to the amplified DNA causes the peak current to decrease because of the slow diffusion of the Hoechst-amplified DNA complex to the electrode surface. The results showed that the oxidation peak current of Hoechst decreased depending on the number of E. coli cells added to the PCR mixture as the template for amplification, and the sensitivity of the method was as low as a single bacterium. Oxygen consumption was detected by direct measurement of the cell-containing culture medium. This method required only 10 μL to be applied on the screen-printed electrode, and the reduction in oxygen current was clearly observed within 30 min when a minimum of 1 × 10 5 cells were present. These results were obtained without purifying the culture, and the samples were applied onto the electrode without any surface modifications. The techniques describes in this report are versatile, because they require the same type of electrode, have simplistic nature, use a hand-held potentiostat, and have

  11. Kernel-Based Relevance Analysis with Enhanced Interpretability for Detection of Brain Activity Patterns

    Directory of Open Access Journals (Sweden)

    Andres M. Alvarez-Meza

    2017-10-01

    Full Text Available We introduce Enhanced Kernel-based Relevance Analysis (EKRA that aims to support the automatic identification of brain activity patterns using electroencephalographic recordings. EKRA is a data-driven strategy that incorporates two kernel functions to take advantage of the available joint information, associating neural responses to a given stimulus condition. Regarding this, a Centered Kernel Alignment functional is adjusted to learning the linear projection that best discriminates the input feature set, optimizing the required free parameters automatically. Our approach is carried out in two scenarios: (i feature selection by computing a relevance vector from extracted neural features to facilitating the physiological interpretation of a given brain activity task, and (ii enhanced feature selection to perform an additional transformation of relevant features aiming to improve the overall identification accuracy. Accordingly, we provide an alternative feature relevance analysis strategy that allows improving the system performance while favoring the data interpretability. For the validation purpose, EKRA is tested in two well-known tasks of brain activity: motor imagery discrimination and epileptic seizure detection. The obtained results show that the EKRA approach estimates a relevant representation space extracted from the provided supervised information, emphasizing the salient input features. As a result, our proposal outperforms the state-of-the-art methods regarding brain activity discrimination accuracy with the benefit of enhanced physiological interpretation about the task at hand.

  12. Detection of outbursts and modeling of the activity during the summer of 2015 with Rosetta

    Science.gov (United States)

    Gicquel, Adeline; von Allmen, Paul; Hofstadter, Mark; MIRO, OSIRIS

    2017-10-01

    The ESA (European Space Agency) Rosetta spacecraft was launched on March 2, 2004 and reached comet 67P/Churyumov-Gerasimenko (67P) in August 2014.Close to perihelion in August 2015, a display of outbursts on 67P, known as the summer fireworks (Vincent et al. 2016), was observed with the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) and the NAVCAM. Vincent et al. (2016) reported the detection of 34 outbursts with one on average every 2.4 nucleus rotations.In the case of the Microwave Instrument for the Rosetta Orbiter (MIRO), the most useful scan pattern for tracking gas abundance before, during, and after an outburst was a series of raster scans across the nucleus along the comet-Sun direction. We identified a spectral feature that is indicative of high velocity gas moving toward the spacecraft as being associated with outbursts. In this particular study, we will report the detection of 6 outbursts with MIRO during the summer of 2015. One of the outbursts detected by MIRO was not observed with OSIRIS or the NAVCAM. We will present results for the gas production rate, as obtained from the H216O emission line observed with MIRO and a numerical model of the radiative transfer in the coma.Our goal is to better understand the physics of outbursts and how the dust is lifted by the gas, by comparing model results to OSIRIS images (sensitive to the dust abundance) and MIRO spectra (sensitive to the gas abundance and velocity). We used a Collisionless Gas Simulation tool developed at JPL to study the gas flow close to the nucleus and the dust trajectories as determined by the three main forces acting on the grains: the drag force, gravity and the radiative pressure. Our main objective is to understand the mechanisms responsible for the outburst and the activity. Past studies have shown that outbursts are in fact a combination of both gas and dust, in which the active surface at the source of the outburst is believed to be approximately 10 times more

  13. Detecting estrogenic activity in water samples withestrogen-sensitive yeast cells using spectrophotometry and fluorescencemicroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wozei, E.; Holman, H-Y.N.; Hermanowicz, S.W.; Borglin S.

    2006-03-15

    Environmental estrogens are environmental contaminants that can mimic the biological activities of the female hormone estrogen in the endocrine system, i.e. they act as endocrine disrupters. Several substances are reported to have estrogen-like activity or estrogenic activity. These include steroid hormones, synthetic estrogens (xenoestrogens), environmental pollutants and phytoestrogens (plant estrogens). Using the chromogenic substrate ortho-nitrophenyl-{beta}-D-galactopyranoside (ONPG) we show that an estrogen-sensitive yeast strain RMY/ER-ERE, with human estrogen receptor (hER{alpha}) gene and the lacZ gene which encodes the enzyme {beta}-galactosidase, is able to detect estrogenic activity in water samples over a wide range of spiked concentrations of the hormonal estrogen 17{beta}-estradiol (E2). Ortho-nitrophenol (ONP), the yellow product of this assay can be detected using spectrophotometry but requires cell lysis to release the enzyme and allow product formation. We improved this aspect in a fluorogenic assay by using fluorescein di-{beta}-D-galactopyranoside (FDG) as a substrate. The product was visualized using fluorescence microscopy without the need to kill, fix or lyse the cells. We show that in live yeast cells, the uptake of E2 and the subsequent production of {beta}-galactosidase enzyme occur quite rapidly, with maximum enzyme-catalyzed fluorescent product formation evident after about 30 minutes of exposure to E2. The fluorogenic assay was applied to a selection of estrogenic compounds and the Synchrotron-based Fourier transform infrared (SR-FTIR) spectra of the cells obtained to better understand the yeast whole cell response to the compounds. The fluorogenic assay is most sensitive to E2, but the SR-FTIR spectra suggest that the cells respond to all the estrogenic compounds tested even when no fluorescent response was detected. These findings are promising and may shorten the duration of environmental water screening and monitoring regimes using

  14. Evidence for the impact of stellar activity on the detectability of solar-like oscillations observed by Kepler

    NARCIS (Netherlands)

    Chaplin, W.J.; Bedding, T.R.; Bonanno, A.; Broomhall, A.M.; Garcia, R.A.; Hekker, S.; Huber, D.; Verner, G.A.; Basu, S.; Elsworth, Y.; Houdek, G.; Mathur, S.; Mosser, B.; New, R.; Stevens, I.R.; Appourchaux, T.; Karoff, C.; Metcalfe, T.S.; Molenda-Zakowicz, J.; Monteiro, M.J.P.F.G.; Thompson, M.J.; Christensen-Dalsgaard, J.; Gilliland, R.L.; Kawaler, S.D.; Kjeldsen, H.; Ballot, J.; Benomar, O.; Corsaro, E.; Campante, T.L.; Gaulme, P.; Hale, S.J.; Handberg, R.; Jarvis, E.; Regulo, C.; Roxburgh, I.W.; Salabert, D.; Stello, D.; Mullally, F.; Li, J.; Wohler, W.

    2011-01-01

    We use photometric observations of solar-type stars, made by the NASA Kepler Mission, to conduct a statistical study of the impact of stellar surface activity on the detectability of solar-like oscillations. We find that the number of stars with detected oscillations falls significantly with

  15. Coupling reporter expression to respiration detects active as well as dormant mycobacteria in vitro and in mouse tissues

    Directory of Open Access Journals (Sweden)

    Subash Chand Verma

    2014-01-01

    Conclusions: Coupling an appropriate reporter to the promoter of ndh-2 gene of M. tuberculosis can make the reporter expression respiration sensitive and thereby reliably detect both active and dormant populations of the reporter strain.

  16. Eyewear Equipped with a Triaxial Accelerometer Detects Age-Related Changes in Ambulatory Activity

    Directory of Open Access Journals (Sweden)

    Shigeyuki Ikeda

    2017-11-01

    Full Text Available Aging is known as a risk factor for gait disorders, which lead to reduced quality of life. Gait disorders can potentially be a sign of a preclinical phase of neurological diseases. Therefore, routine monitoring of changes in ambulatory activity with age can lead to early detection of such disorders. JINS MEME is eyewear equipped with a triaxial accelerometer (mediolateral, anteroposterior, and vertical and capable of measuring acceleration signals during gait. To validate effectiveness of JINS MEME in routinely monitoring age-related changes in ambulatory activity, the present study tested three hypotheses: (1 the frequency of mediolateral body sway during gait increases with age, (2 the variability of gait speed (anteroposterior increases with age, and (3 the frequency of vertical body sway during gait increases with age. The present study included 118 subjects aged 25–69 years. The acceleration signals were measured by JINS MEME while each subject walked down a barrier-free 20-meter-long level corridor at a natural pace. Triaxial variances known for reflecting gait stability, were calculated from the acceleration signals during gait. An association between each of the triaxial variances and age was assessed by multiple linear robust regression analysis including sex as a nuisance covariate. We found significant positive correlations between the anteroposterior variance and age and between the vertical variance and age. The results supported our second and third hypotheses and raised an intriguing possibility that the triaxial accelerometer of JINS MEME is capable of detecting age-related changes in ambulatory activity.

  17. Detection of protease activity by fluorescent protein FRET sensors: from computer simulation to live cells

    Science.gov (United States)

    Goryashchenko, Alexander S.; Khrenova, Maria G.; Savitsky, Alexander P.

    2018-04-01

    Förster resonance energy transfer (FRET) sensors are widely used for the detection of protease activity in vitro and in vivo. Usually they consist of a FRET pair connected with a polypeptide linker containing a specific cleavage site for the relevant protease. Use of the fluorescent proteins as components of the FRET pair allows genetic encoding of such sensors and solves the problem of their delivery into live cells and animals. There are several ways to improve the properties of such sensors, mainly to increase FRET efficiency and therefore the dynamic range. One of the ways to achieve this is to use a non-fluorescent chromoprotein as an acceptor. Molecular dynamic simulations may assist in the construction of linker structures connecting donor and acceptor molecules. Estimation of the orientation factor κ 2 can be obtained by methods based on quantum theory and combined quantum mechanics/molecular mechanics approaches. The linker can be structured by hydrophobic interactions, bringing it into a closed conformation that shortens the distance between donor and acceptor and, consequently, increases FRET efficiency. We analyzed the effects of different linker structures on the detection of caspase-3 activity using a non-fluorescent acceptor. Also we have constructed the Tb3+- TagRFP sensor in which a complex of the terbium ion and terbium-binding peptide is used as a donor. This allowed us to use the unique property of lanthanide ions—fluorescence lifetime up to milliseconds—to perform measurements with time delay and exclude the nanosecond-order fluorescence. Using our systems as a starting point, by changing the recognition site in the linker it is possible to perform imaging of different protease activity in vitro or in vivo.

  18. Radiological Health Protection Issues Associated with Use of Active Detection Technology Systems for Detection of Radioactive Threat Materials

    Science.gov (United States)

    2013-07-01

    materials, such as lead, tin, gadolinium and boron to improve the photon detection efficiency of the base material. These organic scintillators also...shielding material and the stopping of a muon within SNM produces highly-energetic x rays that are isotope specific (Close et al., 1978; NCRP, 2003c) and...should also be processed through a multi- channel analyzer (MCA) to provide for an accurate identification of isotopes in SNM (Stocki, 2010

  19. High resolution analysis of the human transcriptome: detection of extensive alternative splicing independent of transcriptional activity

    Directory of Open Access Journals (Sweden)

    Rouet Fabien

    2009-10-01

    transcriptional activity, indicating that the controls for transcript generation and transcription are distinct, and require novel tools in order to detect changes in specific transcript quantity. Our results demonstrate that the SpliceArray™ design will provide researchers with a robust platform to detect and quantify specific changes not only in overall gene expression, but also at the individual transcript level.

  20. Fluorescently labeled inhibitors detect localized serine protease activities in Drosophila melanogaster pole cells, embryos, and ovarian egg chambers

    DEFF Research Database (Denmark)

    Jakobsen, Rasmus Kragh; Ono, S.; Powers, J. C.

    2005-01-01

    processes that they mediate. Until only recently, the tools to conveniently address the question of where and when serine proteases are active within complex tissues have been lacking. In order to detect spatially restricted serine protease activities in Drosophila embryos and ovaries we introduce...... activity localized to the oocyte-somatic follicle cell interface of the developing egg chamber. Our results suggest that this technique holds promise to identify new spatially restricted activities in adult Drosophila tissues and developing embryos....

  1. Brain Activity in Patients With Adductor Spasmodic Dysphonia Detected by Functional Magnetic Resonance Imaging.

    Science.gov (United States)

    Kiyuna, Asanori; Kise, Norimoto; Hiratsuka, Munehisa; Kondo, Shunsuke; Uehara, Takayuki; Maeda, Hiroyuki; Ganaha, Akira; Suzuki, Mikio

    2017-05-01

    Spasmodic dysphonia (SD) is considered a focal dystonia. However, the detailed pathophysiology of SD remains unclear, despite the detection of abnormal activity in several brain regions. The aim of this study was to clarify the pathophysiological background of SD. This is a case-control study. Both task-related brain activity measured by functional magnetic resonance imaging by reading the five-digit numbers and resting-state functional connectivity (FC) measured by 150 T2-weighted echo planar images acquired without any task were investigated in 12 patients with adductor SD and in 16 healthy controls. The patients with SD showed significantly higher task-related brain activation in the left middle temporal gyrus, left thalamus, bilateral primary motor area, bilateral premotor area, bilateral cerebellum, bilateral somatosensory area, right insula, and right putamen compared with the controls. Region of interest voxel FC analysis revealed many FC changes within the cerebellum-basal ganglia-thalamus-cortex loop in the patients with SD. Of the significant connectivity changes between the patients with SD and the controls, the FC between the left thalamus and the left caudate nucleus was significantly correlated with clinical parameters in SD. The higher task-related brain activity in the insula and cerebellum was consistent with previous neuroimaging studies, suggesting that these areas are one of the unique characteristics of phonation-induced brain activity in SD. Based on FC analysis and their significant correlations with clinical parameters, the basal ganglia network plays an important role in the pathogenesis of SD. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  2. Enzyme-activity mutations detected in mice after paternal fractionated irradiation

    International Nuclear Information System (INIS)

    Charles, D.J.; Pretsch, W.

    1986-01-01

    (101/E1 X C3H/E1)F 1 -hybrid male mice were exposed in a 24-h fractionation interval to either 3.0 + 3.0-Gy or 5.1 + 5.1-Gy X-irradiation, and mated to untreated Test-stock females. The offspring were examined for mutations at 7 recessive specific loci and for activity alterations of erythrocyte enzymes controlled presumably by 12 loci. No enzyme-activity mutant was found in 3610 F 1 -offspring of the control group. In the experimental groups, no mutant was detected in 533 (3.0 + 3.0 Gy) and 173 (5.1 + 5.1 Gy) offspring from postspermatogonial germ cells treated. After treatment of spermatogonia, 1 mutant in 3388 F 1 -offspring of the 3.0 + 3.0-Gy group, and 5 mutants in 3187 F 1 offspring of the 5.1 + 5.1-Gy group were found. The mutants were all genetically confirmed. The frequency (expressed as mutants/locus/gamete) of enzyme-activity mutations is 2 (5.1 + 5.1-Gy group) to 10 (3.0 + 3.0-Gy group) times lower than the frequency of recessive specific-locus mutations. (Auth.)

  3. Machine Learning Detects Pan-cancer Ras Pathway Activation in The Cancer Genome Atlas.

    Science.gov (United States)

    Way, Gregory P; Sanchez-Vega, Francisco; La, Konnor; Armenia, Joshua; Chatila, Walid K; Luna, Augustin; Sander, Chris; Cherniack, Andrew D; Mina, Marco; Ciriello, Giovanni; Schultz, Nikolaus; Sanchez, Yolanda; Greene, Casey S

    2018-04-03

    Precision oncology uses genomic evidence to match patients with treatment but often fails to identify all patients who may respond. The transcriptome of these "hidden responders" may reveal responsive molecular states. We describe and evaluate a machine-learning approach to classify aberrant pathway activity in tumors, which may aid in hidden responder identification. The algorithm integrates RNA-seq, copy number, and mutations from 33 different cancer types across The Cancer Genome Atlas (TCGA) PanCanAtlas project to predict aberrant molecular states in tumors. Applied to the Ras pathway, the method detects Ras activation across cancer types and identifies phenocopying variants. The model, trained on human tumors, can predict response to MEK inhibitors in wild-type Ras cell lines. We also present data that suggest that multiple hits in the Ras pathway confer increased Ras activity. The transcriptome is underused in precision oncology and, combined with machine learning, can aid in the identification of hidden responders. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. Alkaline phosphatase labeled SERS active sandwich immunoassay for detection of Escherichia coli

    Science.gov (United States)

    Bozkurt, Akif Goktug; Buyukgoz, Guluzar Gorkem; Soforoglu, Mehmet; Tamer, Ugur; Suludere, Zekiye; Boyaci, Ismail Hakki

    2018-04-01

    In this study, a sandwich immunoassay method utilizing enzymatic activity of alkaline phosphatase (ALP) on 5-bromo-4-chloro-3-indolyl phosphate (BCIP) for Escherichia coli (E. coli) detection was developed using surface enhanced Raman spectroscopy (SERS). For this purpose, spherical magnetic gold coated core-shell nanoparticles (MNPs-Au) and rod shape gold nanoparticles (Au-NRs) were synthesized and modified for immunomagnetic separation (IMS) of E. coli from the solution. In order to specify the developed method to ALP activity, Au-NRs were labeled with this enzyme. After successful construction of the immunoassay, BCIP substrate was added to produce the SERS-active product; 5-bromo-4-chloro-3-indole (BCI). A good linearity (R2 = 0.992) was established between the specific SERS intensity of BCI at 600 cm- 1 and logarithmic E. coli concentration in the range of 1.7 × 101-1.7 × 106 cfu mL- 1. LOD and LOQ values were also calculated and found to be 10 cfu mL- 1 and 30 cfu mL- 1, respectively.

  5. T-SPOT.TB in Detection of Active Tuberculosis During Pregnancy: A Retrospective Study in China.

    Science.gov (United States)

    Chen, Qiaopei; Guo, Xuxiao; Wang, Xinfeng; Wang, Maoshui

    2016-01-06

    Interferon-gamma release assays have not been validated in active TB among pregnant women. Therefore, the objective of this retrospective study was to estimate the diagnostic value of T-SPOT.TB in active TB among pregnant women. Between May 2012 and May 2015, 26 consecutive pregnant women with suspected TB were enrolled in our study. The clinicopathological characteristics and T-SPOT.TB results were reviewed and analyzed. Pregnant patients were divided into a TB group (n=21) and a Non-TB group (n=5). In the TB group, 5 patients had pulmonary TB, 5 had pulmonary TB+ extrapulmonary TB, and 11 had exclusively extrapulmonary TB. The most common site of extrapulmonary TB was pleural (n=11). Statistical analysis showed that the lymphocyte count in the TB group was lower than in the Non-TB group (Pgood performance in detection of active tuberculosis during pregnancy. Interferon gamma release assay for TB screening of pregnant women is recommended in clinical practice because it may be a more appropriate diagnostic tool than the tuberculin skin test.

  6. Cavitand-functionalized porous silicon as an active surface for organophosphorus vapor detection.

    Science.gov (United States)

    Tudisco, Cristina; Betti, Paolo; Motta, Alessandro; Pinalli, Roberta; Bombaci, Luigi; Dalcanale, Enrico; Condorelli, Guglielmo G

    2012-01-24

    This paper reports on the preparation of a porous silicon-based material covalently functionalized with cavitand receptors suited for the detection of organophosphorus vapors. Two different isomeric cavitands, both containing one acid group at the upper rim, specifically designed for covalent anchoring on silicon, were grafted on H-terminated porous silicon (PSi) by thermal hydrosilylation. The covalently functionalized surfaces and their complexation properties were characterized by combining different analytical techniques, namely X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and mass spectroscopy analysis coupled with thermal desorption experiments. Complexation experiments were performed by exposing both active surfaces and a control surface consisting of PSi functionalized with a structurally similar but inactive methylene-bridged cavitand (MeCav) to dimethyl methylphosphonate (DMMP) vapors. Comparison between active and inactive surfaces demonstrated the recognition properties of the new surfaces. Finally, the nature of the involved interactions, the energetic differences between active and inactive surfaces toward DMMP complexation, and the comparison with a true nerve gas agent (sarin) were studied by DFT modeling. The results revealed the successful grafting reaction, the specific host-guest interactions of the PSi-bonded receptors, and the reversibility of the guest complexation.

  7. A Rapid Screening Analysis of Antioxidant Compounds in Native Australian Food Plants Using Multiplexed Detection with Active Flow Technology Columns

    Directory of Open Access Journals (Sweden)

    Emmanuel Janaka Rochana Rupesinghe

    2016-01-01

    Full Text Available Conventional techniques for identifying antioxidant and phenolic compounds in native Australian food plants are laborious and time-consuming. Here, we present a multiplexed detection technique that reduces analysis time without compromising separation performance. This technique is achieved using Active Flow Technology-Parallel Segmented Flow (AFT-PSF columns. Extracts from cinnamon myrtle (Backhousia myrtifolia and lemon myrtle (Backhousia citriodora leaves were analysed via multiplexed detection using an AFT-PSF column with underivatised UV-VIS, mass spectroscopy (MS, and the 2,2-diphenyl-1-picrylhydrazyl (DPPH• derivatisation for antioxidants as detection methods. A number of antioxidant compounds were detected in the extracts of each leaf extract.

  8. THE SECOND CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE

    International Nuclear Information System (INIS)

    Ackermann, M.; Ajello, M.; Allafort, A.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Bottacini, E.; Antolini, E.; Bonamente, E.; Atwood, W. B.; Bouvier, A.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Barbiellini, G.; Bastieri, D.

    2011-01-01

    The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented. The second LAT AGN catalog (2LAC) includes 1017 γ-ray sources located at high Galactic latitudes (|b| > 10°) that are detected with a test statistic (TS) greater than 25 and associated statistically with AGNs. However, some of these are affected by analysis issues and some are associated with multiple AGNs. Consequently, we define a Clean Sample which includes 886 AGNs, comprising 395 BL Lacertae objects (BL Lac objects), 310 flat-spectrum radio quasars (FSRQs), 157 candidate blazars of unknown type (i.e., with broadband blazar characteristics but with no optical spectral measurement yet), 8 misaligned AGNs, 4 narrow-line Seyfert 1 (NLS1s), 10 AGNs of other types, and 2 starburst galaxies. Where possible, the blazars have been further classified based on their spectral energy distributions (SEDs) as archival radio, optical, and X-ray data permit. While almost all FSRQs have a synchrotron-peak frequency 14 Hz, about half of the BL Lac objects have a synchrotron-peak frequency >10 15 Hz. The 2LAC represents a significant improvement relative to the first LAT AGN catalog (1LAC), with 52% more associated sources. The full characterization of the newly detected sources will require more broadband data. Various properties, such as γ-ray fluxes and photon power-law spectral indices, redshifts, γ-ray luminosities, variability, and archival radio luminosities and their correlations are presented and discussed for the different blazar classes. The general trends observed in 1LAC are confirmed.

  9. SERS-active Ag Nanostars Substrates for Sensitive Detection of Ethyl Carbamate in Wine.

    Science.gov (United States)

    Li, Manli; Zhao, Yuan; Cui, Malin; Wang, Chan; Song, Qijun

    2016-01-01

    A simple and sensitive surface-enhanced Raman scattering (SERS) method for the detection of ethyl carbamate (EC) is reported in this work. Star-shaped silver nanostars (Ag NSs) were used as a novel SERS substrate. In comparison to other plasmonic nanoparticles (NPs), including Au NPs, Au NSs and Ag NPs, Ag NSs exhibit best SERS activity. Raman signal of EC at a trace level can be enhanced by several orders of magnitude with the help of Ag NSs. The Raman intensity of EC increased linearly with an increase of the EC concentration in the range from 5 × 10(-9) mol L(-1) to 1.0 × 10(-4) mol L(-1) with detection limit (LOD) of 1.37 × 10(-9) mol L(-1) (S/N = 3). The developed SERS approach also has the advantages of being simple, fast and requiring less amount of the sample. It could serve as a useful technology for the rapid determination of EC in both alcoholic beverages and fermented food.

  10. Detection of volcanic activity at Mt. Etna using the experimental infrasound array at Meron, Israel

    Science.gov (United States)

    Applbaum, David; Price, Colin

    2015-04-01

    Volcanic activity has long been known as a natural producer of very low frequency acoustic waves, known as infrasound. Because of its proximity to both Europe and Tunisia, many observations of Mt. Etna have been made by various infrasound arrays, especially by IS48, the Tunisian infrasound array that is part of the International Monitoring System of the Comprehensive Nuclear Test Ban Treaty Organization. However, seasonal stratospheric wind changes cause infrasound to propagate well in the stratospheric waveguide either eastward or westward, in winter and summer respectively. For this reason, except in cases of wind reversal due to sudden stratospheric warming (SSW), all of the above observations were made in summer, from west of Mt. Etna. Upon studying the first four years of data from our experimental array in the north of Israel, we noticed that a great number of our winter-time detections come from a specific azimuth to the north west. Comparing these with the Reviewed Events Bulletin of CTBTO, we were able to indeed conclude that these detections likely come from Mt. Etna, over 2000 km away. Here we show some of these observations, the first extensive winter-time observations of Mt. Etna in infrasound

  11. Detection of active corrosion in reinforced and prestressed concrete: overview of NIST TIP project

    Science.gov (United States)

    Gonzalez-Nunez, M. A.; Nanni, A.; Matta, F.; Ziehl, P.

    2011-04-01

    The US transportation infrastructure has been receiving intensive public and private attention in recent years. The Federal Highway Administration estimates that 42 percent of the nearly 600,000 bridges in the Unites States are in need of structural or functional rehabilitation1. Corrosion of reinforcement steel is the main durability issue for reinforced and prestressed concrete structures, especially in coastal areas and in regions where de-icing salts are regularly used. Acoustic Emission (AE) has proved to be a promising method for detecting corrosion in steel reinforced and prestressed concrete members. This type of non-destructive test method primarily measures the magnitude of energy released within a material when physically strained. The expansive ferrous byproducts resulting from corrosion induce pressure at the steel-concrete interface, producing longitudinal and radial microcracks that can be detected by AE sensors. In the experimental study presented herein, concrete block specimens with embedded steel reinforcing bars and strands were tested under accelerated corrosion to relate the AE activity with the onset and propagation stages of corrosion. AE data along with half cell potential measurements and galvanic current were recorded to examine the deterioration process. Finally, the steel strands and bars were removed from the specimens, cleaned and weighed. The results were compared vis-à-vis Faraday's law to correlate AE measurements with degree of corrosion in each block.

  12. A framework for activity detection in wide-area motion imagery

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Reid B [Los Alamos National Laboratory; Ruggiero, Christy E [Los Alamos National Laboratory; Morrison, Jack D [Los Alamos National Laboratory

    2009-01-01

    Wide-area persistent imaging systems are becoming increasingly cost effective and now large areas of the earth can be imaged at relatively high frame rates (1-2 fps). The efficient exploitation of the large geo-spatial-temporal datasets produced by these systems poses significant technical challenges for image and video analysis and data mining. In recent years there has been significant progress made on stabilization, moving object detection and tracking and automated systems now generate hundreds to thousands of vehicle tracks from raw data, with little human intervention. However, the tracking performance at this scale, is unreliable and average track length is much smaller than the average vehicle route. This is a limiting factor for applications which depend heavily on track identity, i.e. tracking vehicles from their points of origin to their final destination. In this paper we propose and investigate a framework for wide-area motion imagery (W AMI) exploitation that minimizes the dependence on track identity. In its current form this framework takes noisy, incomplete moving object detection tracks as input, and produces a small set of activities (e.g. multi-vehicle meetings) as output. The framework can be used to focus and direct human users and additional computation, and suggests a path towards high-level content extraction by learning from the human-in-the-loop.

  13. Second-Generation Thermal Neutron Activation Sensor for Confirmatory Land-Mine Detection

    International Nuclear Information System (INIS)

    Edward Clifford; Harry Ing; John McFee; H. Robert Andrews; Tom Cousins

    2000-01-01

    This paper describes the development of the Improved Land-Mine Detector System (ILDS), a vehicle-mounted nonmetallic land-mine detector. The ILDS consists of a custom teleoperated vehicle carrying an infrared imager, an electromagnetic induction detector, and a ground probing radar-which scan the ground in front of the vehicle. Custom navigation and data fusion software combine information from scanning sensors and navigation systems to detect and automatically track suspect targets until the confirmation detector at the rear of the system is positioned to within 30 cm of the target location. The confirmation detector, using thermal neutron activation (TNA) to detect bulk nitrogen in explosives, then dwells over the target for 10 to 120 s. In U.S. government tests (summer 1998), the ILDS advanced development model (ADM) placed first or second out of five competitors on every test. The construction of the second-generation TNA detector and preliminary testing should be complete by March 2000. Testing on real mines is expected to start in summer 2000

  14. Fluorometric method for inorganic pyrophosphatase activity detection and inhibitor screening based on click chemistry.

    Science.gov (United States)

    Xu, Kefeng; Chen, Zhonghui; Zhou, Ling; Zheng, Ou; Wu, Xiaoping; Guo, Longhua; Qiu, Bin; Lin, Zhenyu; Chen, Guonan

    2015-01-06

    A fluorometric method for pyrophosphatase (PPase) activity detection was developed based on click chemistry. Cu(II) can coordinate with pyrophosphate (PPi), the addition of pyrophosphatase (PPase) into the above system can destroy the coordinate compound because PPase catalyzes the hydrolysis of PPi into inorganic phosphate and produces free Cu(II), and free Cu(II) can be reduced by sodium ascorbate (SA) to form Cu(I), which in turn initiates the ligating reaction between nonfluorescent 3-azidocoumarins and terminal alkynes to produce a highly fluorescent triazole complex, based on which, a simple and sensitive turn on fluorometric method for PPase can be developed. The fluorescence intensity of the system has a linear relationship with the logarithm of the PPase concentration in the range of 0.5 and 10 mU with a detection limit down to 0.2 mU (S/N = 3). This method is cost-effective and convenient without any labels or complicated operations. The proposed system was applied to screen the potential PPase inhibitor with high efficiency. The proposed method can be applied to diagnosis of PPase-related diseases.

  15. Field Prototype of the ENEA Neutron Active Interrogation Device for the Detection of Dirty Bombs

    Directory of Open Access Journals (Sweden)

    Nadia Cherubini

    2016-10-01

    Full Text Available The Italian National Agency for New Technologies, Energy, and Sustainable Economic Development (ENEA Neutron Active Interrogation (NAI device is a tool designed to improve CBRNE defense. It is designed to uncover radioactive and nuclear threats including those in the form of Improvised Explosive Devices (IEDs, the so-called “dirty bombs”. The NAI device, at its current development stage, allows to detect 6 g of 235U hidden in a package. It is easily transportable, light in weight, and with a real-time response. Its working principle is based on two stages: (1 an “active” stage in which neutrons are emitted by a neutron generator to interact with the item under inspection, and (2 a “passive” stage in which secondary neutrons are detected originating a signal that, once processed, allows recognition of the offence. In particular, a clear indication of the potential threat is obtained by a dedicated software based on the Differential Die-Away Time Analysis method.

  16. Low-Complexity Variable Frame Rate Analysis for Speech Recognition and Voice Activity Detection

    DEFF Research Database (Denmark)

    Tan, Zheng-Hua; Lindberg, Børge

    2010-01-01

    for very low SNR signals. The resulting variable frame rate analysis method is applied to three speech processing tasks that are essential to natural interaction with intelligent environments. First, it is used for improving speech recognition performance in noisy environments. Secondly, the method is used......Frame based speech processing inherently assumes a stationary behavior of speech signals in a short period of time. Over a long time, the characteristics of the signals can change significantly and frames are not equally important, underscoring the need for frame selection. In this paper, we...... for scalable source coding schemes in distributed speech recognition where the target bit rate is met by adjusting the frame rate. Thirdly, it is applied to voice activity detection. Very encouraging results are obtained for all three speech processing tasks....

  17. Experiments for detection of gaseous Po-210 originated from microbial activity in the environment

    International Nuclear Information System (INIS)

    Ishimoto, A.; Momoshima, N.

    2006-01-01

    We attempted to detect gaseous Po-210 (half-life 138d) emitted from organisms in the environment. Gaseous Po-210 was tried to collect in 0.5 M nitric acid solution after passing the atmospheric air through filters and a distilled water bubbler, which would remove aerosols existing in the air. The activity of Po-210 was determined by alpha spectrometry after radiochemical separation and electrolytic deposition of Po-210 on a silver disk. Twenty seven point four mBq of Po-210 was observed when 800 m 3 atmospheric air was sampled. Blank of Po-210 in regents and the sampling system was 4.9-6.8 mBq. The concentration of Po-210 observed in the atmospheric air was, thus about 5 times higher than the background; the results strongly support existence of gaseous Po-210 in the environment. (author)

  18. A Hierarchical Framework Approach for Voice Activity Detection and Speech Enhancement

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2014-01-01

    Full Text Available Accurate and effective voice activity detection (VAD is a fundamental step for robust speech or speaker recognition. In this study, we proposed a hierarchical framework approach for VAD and speech enhancement. The modified Wiener filter (MWF approach is utilized for noise reduction in the speech enhancement block. For the feature selection and voting block, several discriminating features were employed in a voting paradigm for the consideration of reliability and discriminative power. Effectiveness of the proposed approach is compared and evaluated to other VAD techniques by using two well-known databases, namely, TIMIT database and NOISEX-92 database. Experimental results show that the proposed method performs well under a variety of noisy conditions.

  19. Recrystallization inhibition in ice due to ice binding protein activity detected by nuclear magnetic resonance.

    Science.gov (United States)

    Brown, Jennifer R; Seymour, Joseph D; Brox, Timothy I; Skidmore, Mark L; Wang, Chen; Christner, Brent C; Luo, Bing-Hao; Codd, Sarah L

    2014-09-01

    Liquid water present in polycrystalline ice at the interstices between ice crystals results in a network of liquid-filled veins and nodes within a solid ice matrix, making ice a low porosity porous media. Here we used nuclear magnetic resonance (NMR) relaxation and time dependent self-diffusion measurements developed for porous media applications to monitor three dimensional changes to the vein network in ices with and without a bacterial ice binding protein (IBP). Shorter effective diffusion distances were detected as a function of increased irreversible ice binding activity, indicating inhibition of ice recrystallization and persistent small crystal structure. The modification of ice structure by the IBP demonstrates a potential mechanism for the microorganism to enhance survivability in ice. These results highlight the potential of NMR techniques in evaluation of the impact of IBPs on vein network structure and recrystallization processes; information useful for continued development of ice-interacting proteins for biotechnology applications.

  20. Detecting the movement and spawning activity of bigheaded carps with environmental DNA

    Science.gov (United States)

    Erickson, Richard A.; Rees, Christopher B.; Coulter, Alison A.; Merkes, Christopher; McCalla, S. Grace; Touzinsky, Katherine F; Walleser, Liza R.; Goforth, Reuben R.; Amberg, Jon J.

    2016-01-01

    Bigheaded carps are invasive fishes threatening to invade the Great Lakes basin and establish spawning populations, and have been monitored using environmental DNA (eDNA). Not only does eDNA hold potential for detecting the presence of species, but may also allow for quantitative comparisons like relative abundance of species across time or space. We examined the relationships among bigheaded carp movement, hydrography, spawning and eDNA on the Wabash River, IN, USA. We found positive relationships between eDNA and movement and eDNA and hydrography. We did not find a relationship between eDNA and spawning activity in the form of drifting eggs. Our first finding demonstrates how eDNA may be used to monitor species abundance, whereas our second finding illustrates the need for additional research into eDNA methodologies. Current applications of eDNA are widespread, but the relatively new technology requires further refinement.

  1. Remote device to detect the neutrons and gamma-ray activity

    International Nuclear Information System (INIS)

    Ermakov, G.; Korolev, M.; Lopatin, Yu.; Rtishchev, A.

    1999-01-01

    The device for monitoring of gamma activity and neutrons with the following advantages was successfully developed and manufactured: extremely low power consumption which allow the long time of monitoring (up to one year or even more for GM device); high level of the intellect (build in processor); a big memory to remember results (512 Kb) including the date of events (min, hour, day, month, year); extremely simple and highly automated mode of operating; infrared interface to pass information to the external computer; high level of the IP protection; wide range of possible application. The devices could be used as follows: detection of unauthorized movement (removal) of the nuclear material and/or radioactive sources from the facility, monitoring of the radioactivity for different purposes in places with harsh climatic conditions [ru

  2. Active atmosphere-ecosystem exchange of the vast majority of detected volatile organic compounds.

    Science.gov (United States)

    Park, J-H; Goldstein, A H; Timkovsky, J; Fares, S; Weber, R; Karlik, J; Holzinger, R

    2013-08-09

    Numerous volatile organic compounds (VOCs) exist in Earth's atmosphere, most of which originate from biogenic emissions. Despite VOCs' critical role in tropospheric chemistry, studies for evaluating their atmosphere-ecosystem exchange (emission and deposition) have been limited to a few dominant compounds owing to a lack of appropriate measurement techniques. Using a high-mass resolution proton transfer reaction-time of flight-mass spectrometer and an absolute value eddy-covariance method, we directly measured 186 organic ions with net deposition, and 494 that have bidirectional flux. This observation of active atmosphere-ecosystem exchange of the vast majority of detected VOCs poses a challenge to current emission, air quality, and global climate models, which do not account for this extremely large range of compounds. This observation also provides new insight for understanding the atmospheric VOC budget.

  3. SERMs and SARMs: detection of their activities with yeast based bioassays.

    Science.gov (United States)

    Bovee, Toine F H; Thevis, Mario; Hamers, Astrid R M; Peijnenburg, Ad A C M; Nielen, Michel W F; Schoonen, Willem G E J

    2010-01-01

    Selective estrogen receptor modulators (SERMs) and selective androgen receptor modulators (SARMs) are compounds that activate their cognate receptor in particular target tissues without affecting other organs. Many of these compounds will find their use in therapeutic treatments. However, they also will have a high potential for misuse in veterinary practice and the sporting world. Here we demonstrate that yeast estrogen and androgen bioassays can be used to detect SERMs and SARMs, and are also useful screening tools to investigate their mode of action. Six steroidal 11beta-substituents of E2 (SERMs) and some arylpropionamide- and quinoline-based SARMs were tested. In addition, 7 compounds previously tested on AR agonism and determined as inactive in the yeast androgen bioassay, while QSAR modelling revealed strong binding to the human androgen receptor, are now shown to act as AR antagonists. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Active Detectors for Plasma Soft X-Ray Detection at PALS

    Directory of Open Access Journals (Sweden)

    C. Granja

    2010-01-01

    Full Text Available This paper summarizes the work carried out for an experimental study of low-energy nuclear excitation by laser-produced plasma at the PALS Prague laser facility. We describe the adaptation and shielding of single-quantum active radiation detectors developed at IEAP CTU Prague to facilitate their operation inside the laser interaction chamber in the vicinity of the plasma target. The goal of this effort is direct real-time single-quantum detection of plasma soft X-ray radiation with energy above a few keV and subsequent identification of the decay of the excited nuclear states via low-energy gamma rays in a highly radiative environment with strong electromagnetic interference.

  5. Physical activity in young adults: a signal detection analysis of Health Information National Trends Survey (HINTS) 2007 data.

    Science.gov (United States)

    Valle, Carmina G; Tate, Deborah F; Mayer, Deborah K; Allicock, Marlyn; Cai, Jianwen; Campbell, Marci K

    2015-01-01

    Many young adults are insufficiently active to achieve the health benefits of regular physical activity. Using signal detection analysis of data from the 2007 Health Information National Trends Survey, the authors examined distinct subgroups of 18-39 year-old adults who vary in their likelihood of not meeting physical activity recommendations. We randomly split the sample and conducted signal detection analysis on the exploratory half to identify subgroups and interactions among sociodemographic and health communication variables that predicted engaging in less than 150 minutes per week of moderate-intensity physical activity (low physical activity). We compared rates of low physical activity among subgroups with similarly defined subgroups in the validation sample. Overall, 62% of participants did not meet physical activity recommendations. Among 8 subgroups identified, low physical activity rates ranged from 31% to 90%. Predictors of low physical activity were general health, body mass index (BMI), perceived cancer risk, health-related Internet use, and trust in information sources. The least active subgroup (90% low physical activity) included young adults in poor to good health with a BMI of 30.8 or more (obese). The most active subgroup (31% low physical activity) comprised those in very good to excellent health, who used a website to help with diet, weight, or physical activity, and had little to no trust in health information on television. Findings suggest potential intervention communication channels and can inform targeted physical activity interventions for young adults.

  6. Inorganic nanoparticles and the immune system: detection, selective activation and tolerance

    Science.gov (United States)

    Bastús, Neus G.; Sánchez-Tilló, Ester; Pujals, Silvia; Comenge, Joan; Giralt, Ernest; Celada, Antonio; Lloberas, Jorge; Puntes, Victor F.

    2012-03-01

    The immune system is the responsible for body integrity and prevention of external invasion. On one side, nanoparticles are no triggers that the immune system is prepared to detect, on the other side it is known that foreign bodies, not only bacteria, viruses and parasites, but also inorganic matter, can cause various pathologies such as silicosis, asbestosis or inflammatory reactions. Therefore, nanoparticles entering the body, after interaction with proteins, will be either recognized as self-agents or detected by the immune system, encompassing immunostimulation or immunosuppression responses. The nature of these interactions seems to be dictated not specially by the composition of the material but by modifications of NP coating (composition, surface charge and structure). Herein, we explore the use of gold nanoparticles as substrates to carry multifunctional ligands to manipulate the immune system in a controlled manner, from undetection to immunostimulation. Murine bone marrow macrophages can be activated with artificial nanometric objects consisting of a gold nanoparticle functionalized with peptides. In the presence of some conjugates, macrophage proliferation was stopped and pro-inflammatory cytokines were induced. The biochemical type of response depended on the type of conjugated peptide and was correlated with the degree of ordering in the peptide coating. These findings help to illustrate the basic requirements involved in medical NP conjugate design to either activate the immune system or hide from it, in order to reach their targets before being removed by phagocytes. Additionally, it opens up the possibility to modulate the immune response in order to suppress unwanted responses resulting from autoimmunity, or allergy or to stimulate protective responses against pathogens.

  7. Carbon nanotube signal amplification for ultrasensitive fluorescence polarization detection of DNA methyltransferase activity and inhibition.

    Science.gov (United States)

    Huang, Yong; Shi, Ming; Zhao, Limin; Zhao, Shulin; Hu, Kun; Chen, Zheng-Feng; Chen, Jia; Liang, Hong

    2014-04-15

    A versatile sensing platform based on multiwalled carbon nanotube (MWCNT) signal amplification and fluorescence polarization (FP) is developed for the simple and ultrasensitive monitoring of DNA methyltransferase (MTase) activity and inhibition in homogeneous solution. This method uses a dye-labeled DNA probe that possess a doubled-stranded DNA (dsDNA) part for Mtase and its corresponding restriction endonuclease recognition, and a single-stranded DNA part for binding MWCNTs. In the absence of MTase, the dye-labeled DNA is cleaved by restriction endonuclease, and releases very short DNA carrying the dye that cannot bind to MWCNTs, which has relatively small FP value. However, in the presence of MTase, the specific recognition sequence in the dye-labeled DNA probe is methylated and not cleaved by restriction endonuclease. Thus, the dye-labeled methylated DNA product is adsorbed onto MWCNTs via strong π-π stacking interactions, which leads to a significant increase in the FP value due to the enlargement of the molecular volume of the dye-labeled methylated DNA/MWCNTs complex. This provides the basic of a quantitative measurement of MTase activity. By using the MWCNT signal amplification approach, the detection sensitivity can be significantly improved by two orders of magnitude over the previously reported methods. Moreover, this method also has high specificity and a wide dynamic range of over five orders of magnitude. Additionally, the suitability of this sensing platform for MTase inhibitor screening has also been demonstrated. This approach may serve as a general detection platform for sensitive assay of a variety of DNA MTases and screening potential drugs. © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Measurements of meteor smoke particles during the ECOMA-2006 campaign: 1. Particle detection by active photoionization

    Science.gov (United States)

    Rapp, Markus; Strelnikova, Irina

    2009-03-01

    We present a new design of an in situ detector for the study of meteor smoke particles (MSPs) in the middle atmosphere. This detector combines a classical Faraday cup with a xenon-flashlamp for the active photoionization/photodetachment of MSPs and the subsequent detection of corresponding photoelectrons. This instrument was successfully launched in September 2006 from the Andøya Rocket Range in Northern Norway. A comparison of photocurrents measured during this rocket flight and measurements performed in the laboratory proves that observed signatures are truly due to photoelectrons. In addition, the observed altitude cut-off at 60 km (i.e., no signals were observed below this altitude) is fully understood in terms of the mean free path of the photoelectrons in the ambient atmosphere. This interpretation is also proven by a corresponding laboratory experiment. Consideration of all conceivable species which can be ionized by the photons of the xenon-flashlamp demonstrates that only MSPs can quantitatively explain the measured currents below an altitude of 90 km. Above this altitude, measured photocurrents are most likely due to photoionization of nitric oxide. In conclusion, our results demonstrate that the active photoionization and subsequent detection of photoelectrons provides a promising new tool for the study of MSPs in the middle atmosphere. Importantly, this new technique does not rely on the a priori charge of the particles, neither is the accessible particle size range severely limited by aerodynamical effects. Based on the analysis described in this study, the geophysical interpretation of our measurements is presented in the companion paper by Strelnikova, I., et al. [2008. Measurements of meteor smoke particles during the ECOMA-2006 campaign: 2. results. Journal of Atmospheric and Solar-Terrestrial Physics, this issue, doi:10.1016/j.jastp.2008.07.011].

  9. Graph-based representation of behavior in detection and prediction of daily living activities.

    Science.gov (United States)

    Augustyniak, Piotr; Ślusarczyk, Grażyna

    2018-04-01

    Various surveillance systems capture signs of human activities of daily living (ADLs) and store multimodal information as time line behavioral records. In this paper, we present a novel approach to the analysis of a behavioral record used in a surveillance system designed for use in elderly smart homes. The description of a subject's activity is first decomposed into elementary poses - easily detectable by dedicated intelligent sensors - and represented by the share coefficients. Then, the activity is represented in the form of an attributed graph, where nodes correspond to elementary poses. As share coefficients of poses are expressed as attributes assigned to graph nodes, their change corresponding to a subject's action is represented by flow in graph edges. The behavioral record is thus a time series of graphs, which tiny size facilitates storage and management of long-term monitoring results. At the system learning stage, the contribution of elementary poses is accumulated, discretized and probability-ordered leading to a finite list representing the possible transitions between states. Such a list is independently built for each room in the supervised residence, and employed for assessment of the current action in the context of subject's habits and a room purpose. The proposed format of a behavioral record, applied to an adaptive surveillance system, is particularly advantageous for representing new activities not known at the setup stage, for providing a quantitative measure of transitions between poses and for expressing the difference between a predicted and actual action in a numerical way. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Inflight proton activation and damage on a CdTe detection plane

    Science.gov (United States)

    Simões, N.; Maia, J. M.; Curado da Silva, R. M.; Ghithan, S.; Crespo, P.; do Carmo, S. J. C.; Alves, Francisco; Moita, M.; Auricchio, N.; Caroli, E.

    2018-01-01

    Future high-energy space telescope missions require further analysis of orbital environment induced activation and radiation damage on main instruments. A scientific satellite is exposed to the charged particles harsh environment, mainly geomagnetically trapped protons (up to ∼300 MeV) that interact with the payload materials, generating nuclear activation background noise within instruments' operational energy range and causing radiation damage in detector material. As a consequence, instruments' performances deteriorate during the mission time-frame. In order to optimize inflight operational performances of future CdTe high-energy telescope detection planes under orbital radiation environment, we measured and analyzed the effects generated by protons on CdTe ACRORAD detectors with 2.56 cm2 sensitive area and 2 mm thickness. To carry-out this study, several sets of measurements were performed under a ∼14 MeV cyclotron proton beam. Nuclear activation radionuclides' identification was performed. Estimation of activation background generated by short-lived radioisotopes during one day was less than ∼1.3 ×10-5 counts cm-2 s-1 keV-1 up to 800 keV. A noticeable gamma-rays energy resolution degradation was registered (∼60% @ 122 keV, ∼14% @ 511 and ∼2.2% @ 1275 keV) after an accumulated proton fluence of 4.5 ×1010 protons cm-2, equivalent to ∼22 years in-orbit fluence. One year later, the energy resolution of the irradiated prototype showed a good level of performancerecovery.

  11. Valuation of active blind spot detection systems by younger and older adults.

    Science.gov (United States)

    Souders, Dustin J; Best, Ryan; Charness, Neil

    2017-09-01

    Due to their disproportional representation in fatal crashes, younger and older drivers both stand to benefit from in-vehicle safety technologies, yet little is known about how they value such technologies, or their willingness to adopt them. The current study investigated older (aged 65 and greater; N=49) and younger (ages 18-23; N=40) adults' valuation of a blind spot monitor and asked if self-reported visual difficulties while driving predicted the amount participants were willing to pay for a particular system (BMW's Active Blind Spot Detection System) that was demonstrated using a short video. Large and small anchor values ($250 and $500, respectively) were used as between subjects manipulations to examine the effects of initial valuation, and participants proceeded through a short staircase procedure that offered them either the free installation of the system on their current vehicle or a monetary prize ($25-$950) that changed in value according to which option they had selected in the previous step of the staircase procedure. Willingness to use other advanced driver assistance systems (lane-departure warning, automatic lane centering, emergency braking, adaptive cruise control, and self-parking systems) was also analyzed, additionally controlling for prior familiarity of those systems. Results showed that increased age was associated with a higher valuation for the Active Blind Spot Detection System in both the large and small anchor value conditions controlling for income, gender, and technology self-efficacy. Older adults valued blind spot detection about twice as much ($762) as younger adults ($383) in the large anchor condition, though both groups' values were in the range for the current cost of an aftermarket system. Similarly, age was the most robust positive predictor of willingness to adopt other driving technologies, along with system familiarity. Difficulties with driving-related visual factors also positively predicting acceptance levels for

  12. Clinical performance of two visual scoring systems in detecting and assessing activity status of occlusal caries in primary teeth

    DEFF Research Database (Denmark)

    Braga, M M; Ekstrand, K R; Martignon, S

    2010-01-01

    This study aimed to compare the clinical performance of two sets of visual scoring criteria for detecting caries severity and assessing caries activity status in occlusal surfaces. Two visual scoring systems--the Nyvad criteria (NY) and the ICDAS-II including an adjunct system for lesion activity...

  13. Use of different buffers for detection and separation in determination of physio-active components in oolong tea infusion by CZE with amperometric detection.

    Science.gov (United States)

    Yang, Zhiyong; Li, Zicheng; Zhu, Jinkun; Wang, Qingjiang; He, Pingang; Fang, Yuzhi

    2010-05-01

    With a view of simultaneous determination of physio-active ingredients in oolong tea infusion: sugars, amino acids, epigallocatechin gallate and ascorbic acid, a novel CZE with amperometric detection method was studied. Operated in a wall-jet configuration, 100 mmol/L NaOH was used in detecting cell to lead the electrocatalysis oxidation behaviors of the analytes on a 300 mum diameter copper-disc electrode (working electrode), while in separating capillary, a mild alkaline running buffer consisting in a mixture of 30 mmol/L borate and 40 mmol/L phosphates charged and carried analytes to detecting end. The methodology research was performed for system stability and suitability. Under the optimal CE conditions, analytes could be separated within moderate time period. Good linearity between peak area and concentration existed over three orders of magnitude; lower RSD and LOD were achieved. The oolong tea infusion was assayed and result was satisfactory.

  14. Wavelet analysis for detection of phasic electromyographic activity in sleep: influence of mother wavelet and dimensionality reduction.

    Science.gov (United States)

    Fairley, Jacqueline A; Georgoulas, George; Smart, Otis L; Dimakopoulos, George; Karvelis, Petros; Stylios, Chrysostomos D; Rye, David B; Bliwise, Donald L

    2014-05-01

    Phasic electromyographic (EMG) activity during sleep is characterized by brief muscle twitches (duration 100-500ms, amplitude four times background activity). High rates of such activity may have clinical relevance. This paper presents wavelet (WT) analyses to detect phasic EMG, examining both Symlet and Daubechies approaches. Feature extraction included 1s epoch processing with 24 WT-based features and dimensionality reduction involved comparing two techniques: principal component analysis and a feature/variable selection algorithm. Classification was conducted using a linear classifier. Valid automated detection was obtained in comparison to expert human judgment with high (>90%) classification performance for 11/12 datasets. Published by Elsevier Ltd.

  15. Real-time detection of TDP1 activity using a fluorophore-quencher coupled DNA-biosensor

    DEFF Research Database (Denmark)

    Jensen, Pia Wrensted; Falconi, Mattia; Kristoffersen, Emil Laust

    2013-01-01

    Real-time detection of enzyme activities may present the easiest and most reliable way of obtaining quantitative analyses in biological samples. We present a new DNA-biosensor capable of detecting the activity of the potential anticancer drug target tyrosyl-DNA phosphodiesterase 1 (TDP1) in a very...... simple, high throughput, and real-time format. The biosensor is specific for Tdp1 even in complex biological samples, such as human cell extracts, and may consequently find future use in fundamental studies as well as a cancer predictive tool allowing fast analyses of diagnostic cell samples...... activity in pure enzyme fractions as well as in crude cell extracts. In the present study we demonstrate the specificity of the biosensor, its ability to quantitatively detect up- or down-regulated TDP1 activity, and that it may be used for measuring and for analyzing the mechanism of TDP1 inhibition....

  16. Particulate activity accumulated on a moving filter and RCS leak detection.

    Science.gov (United States)

    Peng, Wu-Hung

    2012-08-01

    Analytical equations for calculating the particulate activity accumulated on a moving filter of a containment air particulate radiation monitor due to a reactor coolant system leak in the containment, including the noble gas decay products, were presented. The particulate airborne concentration in the containment was treated by assumptions of a constant reactor coolant leak rate at a constant concentration, a given aerosolizing fraction, a constant removal coefficient to account for the loss due to diffusion, settling, diffusiophoresis, and containment air recirculation operation. The ratio of moving-to-fixed filter activity was presented for radionuclide of various half-lives and for different filter moving speeds. The monitor response at one hour after the initiation of a 1-gallon per minute leak at measured reactor coolant concentrations was compared to the standard deviation of the background count rate for an operating pressurized water reactor. The detectability of a 1-gallon per minute leak in an hour can be demonstrated if the aerosolization percentage of the radionuclide in the leaked coolant is at least a few percent.

  17. Evidence for frozen melts in the mid-lithosphere detected from active-source seismic data.

    Science.gov (United States)

    Ohira, Akane; Kodaira, Shuichi; Nakamura, Yasuyuki; Fujie, Gou; Arai, Ryuta; Miura, Seiichi

    2017-11-17

    The interactions of the lithospheric plates that form the Earth's outer shell provide much of the evidentiary basis for modern plate tectonic theory. Seismic discontinuities in the lithosphere arising from mantle convection and plate motion provide constraints on the physical and chemical properties of the mantle that contribute to the processes of formation and evolution of tectonic plates. Seismological studies during the past two decades have detected seismic discontinuities within the oceanic lithosphere in addition to that at the lithosphere-asthenosphere boundary (LAB). However, the depth, distribution, and physical properties of these discontinuities are not well constrained, which makes it difficult to use seismological data to examine their origin. Here we present new active-source seismic data acquired along a 1,130 km profile across an old Pacific plate (148-128 Ma) that show oceanic mid-lithosphere discontinuities (oceanic MLDs) distributed 37-59 km below the seafloor. The presence of the oceanic MLDs suggests that frozen melts that accumulated at past LABs have been preserved as low-velocity layers within the current mature lithosphere. These observations show that long-offset, high-frequency, active-source seismic data can be used to image mid-lithospheric structure, which is fundamental to understanding the formation and evolution of tectonic plates.

  18. Speech Waveform Compression Using Robust Adaptive Voice Activity Detection for Nonstationary Noise

    Directory of Open Access Journals (Sweden)

    Hsiao-Chun Wu

    2008-03-01

    Full Text Available The voice activity detection (VAD is crucial in all kinds of speech applications. However, almost all existing VAD algorithms suffer from the nonstationarity of both speech and noise. To combat this difficulty, we propose a new voice activity detector, which is based on the Mel-energy features and an adaptive threshold related to the signal-to-noise ratio (SNR estimates. In this paper, we first justify the robustness of the Bayes classifier using the Mel-energy features over that using the Fourier spectral features in various noise environments. Then, we design an algorithm using the dynamic Mel-energy estimator and the adaptive threshold, which depends on the SNR estimates. In addition, a realignment scheme is incorporated to correct the sparse-and-spurious noise estimates. Numerous simulations are carried out to evaluate the performance of our proposed VAD method and the comparisons are made with a couple of existing representative schemes, namely, the VAD using the likelihood ratio test with Fourier spectral energy features and that based on the enhanced time-frequency parameters. Three types of noises, namely, white noise (stationary, babble noise (nonstationary, and vehicular noise (nonstationary were artificially added by the computer for our experiments. As a result, our proposed VAD algorithm significantly outperforms other existing methods as illustrated by the corresponding receiver operating characteristics (ROC curves. Finally, we demonstrate one of the major applications, namely, speech waveform compression associated with our new robust VAD scheme and quantify the effectiveness in terms of compression efficiency.

  19. Speech Waveform Compression Using Robust Adaptive Voice Activity Detection for Nonstationary Noise

    Directory of Open Access Journals (Sweden)

    Syed WaheeduddinQ

    2008-01-01

    Full Text Available The voice activity detection (VAD is crucial in all kinds of speech applications. However, almost all existing VAD algorithms suffer from the nonstationarity of both speech and noise. To combat this difficulty, we propose a new voice activity detector, which is based on the Mel-energy features and an adaptive threshold related to the signal-to-noise ratio (SNR estimates. In this paper, we first justify the robustness of the Bayes classifier using the Mel-energy features over that using the Fourier spectral features in various noise environments. Then, we design an algorithm using the dynamic Mel-energy estimator and the adaptive threshold, which depends on the SNR estimates. In addition, a realignment scheme is incorporated to correct the sparse-and-spurious noise estimates. Numerous simulations are carried out to evaluate the performance of our proposed VAD method and the comparisons are made with a couple of existing representative schemes, namely, the VAD using the likelihood ratio test with Fourier spectral energy features and that based on the enhanced time-frequency parameters. Three types of noises, namely, white noise (stationary, babble noise (nonstationary, and vehicular noise (nonstationary were artificially added by the computer for our experiments. As a result, our proposed VAD algorithm significantly outperforms other existing methods as illustrated by the corresponding receiver operating characteristics (ROC curves. Finally, we demonstrate one of the major applications, namely, speech waveform compression associated with our new robust VAD scheme and quantify the effectiveness in terms of compression efficiency.

  20. Real-time detecting gelatinases activity in living cells by FRET imaging

    Science.gov (United States)

    Yang, Jie; Zhang, Zhihong; Liu, Bifeng; Luo, Qingming

    2006-01-01

    Degradation of the extracellular matrix by Matrix metalloproteinases (MMPs) not only enhances tumor invasion, but also affects tumor cell behaviour and leads to cancer progression. To monitor gelatinases (contain MMP2 and MMP9) activity in living cells, we constructed a vector that encoded a gelatinases recognition site (GRS) between citrine (mutation of EYFP Q69M) in N terminal and ECFP in C terminal. Because Gelatinases are secretory proteins and act outside of cell, an expressing vector displayed the fusion protein on cellular surface was used for this FRET gene probe. On expression of YFP-GRS-ECFP in MCF-7 cells that expressed no gelatinases, we were able to observe the efficient transfer of energy from excited ECFP to YFP within the YFP-GRS-ECFP molecule. However, the fusion protein YFP-GRS-ECFP was expressed in MDA-MB 453s cell line with high secretory gelatinases, so YFP-GRS-ECFP was cleaved by gelatinases, no such transfer of energy was detected and fluorescence signal disappeared in YFP channel since YFP protein was cut down. Moreover, Doxycycline, a MMP inhibitor, could make FRET signal increase and fluorescence signal appeared in YFP channel. Thus, the FRET probe YFP-GRS-ECFP can sensitively and reliably monitor gelatinases activation in living cells and can be used for screening MMP inhibitors.

  1. Two staining methods for selectively detecting isomaltase and maltase activity in electrophoresis gels.

    Science.gov (United States)

    Finlayson, S D; Moore, P A; Johnston, J R; Berry, D R

    1990-05-01

    Two methods for specifically detecting maltase, alpha-glucosidase, or isomaltase activity in electrophoresis gels are described. Both systems couple the formation of glucose by enzyme action on maltose or isomaltose to the generation of a colored product. System A uses an agarose overlay which contains substrate, glucose oxidase, peroxidase, 2,4-dichlorophenol, and 4-L-amino-phenazone. A purple color is produced at the site of enzyme activity. No hazardous chemicals are used at any stage. The stain is simple, rapid, sensitive, and inexpensive and does not interfere with subsequent protein staining. However, the stain is not permanent. System B was developed to give a permanent stain. The gel is overlaid with agarose containing substrate, glucose oxidase, phenazine methosulfate, and nitroblue tetrazolium. Glucose production results in the nitroblue tetrazolium being oxidized to an insoluble formazan with a dark blue color. This stain is also sensitive, rapid, and inexpensive but does use hazardous chemicals and if overstaining occurs this can interfere with subsequent protein staining. Neither system inactivates the localized enzymes which can be recovered from the gel if desired.

  2. Human facial skin detection in thermal video to effectively measure electrodermal activity (EDA)

    Science.gov (United States)

    Kaur, Balvinder; Hutchinson, J. Andrew; Leonard, Kevin R.; Nelson, Jill K.

    2011-06-01

    In the past, autonomic nervous system response has often been determined through measuring Electrodermal Activity (EDA), sometimes referred to as Skin Conductance (SC). Recent work has shown that high resolution thermal cameras can passively and remotely obtain an analog to EDA by assessing the activation of facial eccrine skin pores. This paper investigates a method to distinguish facial skin from non-skin portions on the face to generate a skin-only Dynamic Mask (DM), validates the DM results, and demonstrates DM performance by removing false pore counts. Moreover, this paper shows results from these techniques using data from 20+ subjects across two different experiments. In the first experiment, subjects were presented with primary screening questions for which some had jeopardy. In the second experiment, subjects experienced standard emotion-eliciting stimuli. The results from using this technique will be shown in relation to data and human perception (ground truth). This paper introduces an automatic end-to-end skin detection approach based on texture feature vectors. In doing so, the paper contributes not only a new capability of tracking facial skin in thermal imagery, but also enhances our capability to provide non-contact, remote, passive, and real-time methods for determining autonomic nervous system responses for medical and security applications.

  3. Detecting short-term responses to weekend recreation activity: desert bighorn sheep avoidance of hiking trails

    Science.gov (United States)

    Longshore, Kathleen M.; Lowrey, Chris; Thompson, Daniel B.

    2013-01-01

    To study potential effects of recreation activity on habitat use of desert bighorn sheep (Ovis canadensis nelsoni), we placed Global Positioning System collars on 10 female bighorn sheep within the Wonderland of Rocks–Queen Mountain region of Joshua Tree National Park (JOTR), California, USA, from 2002 to 2004. Recreation use was highest from March to April and during weekends throughout the year. Daily use of recreation trails was highest during midday. By comparing habitat use (slope, ruggedness, distance to water, and distance to recreation trails) of female bighorn sheep on weekdays versus weekends, we were able to detect short-term shifts in behavior in response to recreation. In a logistic regression of bighorn sheep locations versus random locations for March and April, female locations at midday (1200 hours) were significantly more distant from recreation trails on weekends compared with weekdays. Our results indicate that within this region of JOTR, moderate to high levels of human recreation activity may temporarily exclude bighorn females from their preferred habitat. However, the relative proximity of females to recreation trails during the weekdays before and after such habitat shifts indicates that these anthropogenic impacts were short-lived. Our results have implications for management of wildlife on public lands where the co-existence of wildlife and recreational use is a major goal.

  4. Wavelet based automated postural event detection and activity classification with single imu - biomed 2013.

    Science.gov (United States)

    Lockhart, Thurmon E; Soangra, Rahul; Zhang, Jian; Wu, Xuefan

    2013-01-01

    Mobility characteristics associated with activity of daily living such as sitting down, lying down, rising up, and walking are considered to be important in maintaining functional independence and healthy life style especially for the growing elderly population. Characteristics of postural transitions such as sit-to-stand are widely used by clinicians as a physical indicator of health, and walking is used as an important mobility assessment tool. Many tools have been developed to assist in the assessment of functional levels and to detect a person’s activities during daily life. These include questionnaires, observation, diaries, kinetic and kinematic systems, and validated functional tests. These measures are costly and time consuming, rely on subjective patient recall and may not accurately reflect functional ability in the patient’s home. In order to provide a low-cost, objective assessment of functional ability, inertial measurement unit (IMU) using MEMS technology has been employed to ascertain ADLs. These measures facilitate long-term monitoring of activity of daily living using wearable sensors. IMU system are desirable in monitoring human postures since they respond to both frequency and the intensity of movements and measure both dc (gravitational acceleration vector) and ac (acceleration due to body movement) components at a low cost. This has enabled the development of a small, lightweight, portable system that can be worn by a free-living subject without motion impediment – TEMPO (Technology Enabled Medical Precision Observation). Using this IMU system, we acquired indirect measures of biomechanical variables that can be used as an assessment of individual mobility characteristics with accuracy and recognition rates that are comparable to the modern motion capture systems. In this study, five subjects performed various ADLs and mobility measures such as posture transitions and gait characteristics were obtained. We developed postural event detection

  5. Accurate means of detecting and characterizing abnormal patterns of ventricular activation by phase image analysis

    International Nuclear Information System (INIS)

    Botvinick, E.H.; Frais, M.A.; Shosa, D.W.; O'Connell, J.W.; Pacheco-Alvarez, J.A.; Scheinman, M.; Hattner, R.S.; Morady, F.; Faulkner, D.B.

    1982-01-01

    The ability of scintigraphic phase image analysis to characterize patterns of abnormal ventricular activation was investigated. The pattern of phase distribution and sequential phase changes over both right and left ventricular regions of interest were evaluated in 16 patients with normal electrical activation and wall motion and compared with those in 8 patients with an artificial pacemaker and 4 patients with sinus rhythm with the Wolff-Parkinson-White syndrome and delta waves. Normally, the site of earliest phase angle was seen at the base of the interventricular septum, with sequential change affecting the body of the septum and the cardiac apex and then spreading laterally to involve the body of both ventricles. The site of earliest phase angle was located at the apex of the right ventricle in seven patients with a right ventricular endocardial pacemaker and on the lateral left ventricular wall in one patient with a left ventricular epicardial pacemaker. In each case the site corresponded exactly to the position of the pacing electrode as seen on posteroanterior and left lateral chest X-ray films, and sequential phase changes spread from the initial focus to affect both ventricles. In each of the patients with the Wolff-Parkinson-White syndrome, the site of earliest ventricular phase angle was located, and it corresponded exactly to the site of the bypass tract as determined by endocardial mapping. In this way, four bypass pathways, two posterior left paraseptal, one left lateral and one right lateral, were correctly localized scintigraphically. On the basis of the sequence of mechanical contraction, phase image analysis provides an accurate noninvasive method of detecting abnormal foci of ventricular activation

  6. Correlation set analysis: detecting active regulators in disease populations using prior causal knowledge

    Directory of Open Access Journals (Sweden)

    Huang Chia-Ling

    2012-03-01

    Full Text Available Abstract Background Identification of active causal regulators is a crucial problem in understanding mechanism of diseases or finding drug targets. Methods that infer causal regulators directly from primary data have been proposed and successfully validated in some cases. These methods necessarily require very large sample sizes or a mix of different data types. Recent studies have shown that prior biological knowledge can successfully boost a method's ability to find regulators. Results We present a simple data-driven method, Correlation Set Analysis (CSA, for comprehensively detecting active regulators in disease populations by integrating co-expression analysis and a specific type of literature-derived causal relationships. Instead of investigating the co-expression level between regulators and their regulatees, we focus on coherence of regulatees of a regulator. Using simulated datasets we show that our method performs very well at recovering even weak regulatory relationships with a low false discovery rate. Using three separate real biological datasets we were able to recover well known and as yet undescribed, active regulators for each disease population. The results are represented as a rank-ordered list of regulators, and reveals both single and higher-order regulatory relationships. Conclusions CSA is an intuitive data-driven way of selecting directed perturbation experiments that are relevant to a disease population of interest and represent a starting point for further investigation. Our findings demonstrate that combining co-expression analysis on regulatee sets with a literature-derived network can successfully identify causal regulators and help develop possible hypothesis to explain disease progression.

  7. Minimal detectable change of the London chest activity of daily living scale in patients with COPD.

    Science.gov (United States)

    Bisca, Gianna Waldrich; Proença, Mahara; Salomão, Alexandre; Hernandes, Nidia A; Pitta, Fabio

    2014-01-01

    Dyspnea and fatigue frequently impair the ability to perform activities of daily living (ADL) in patients with chronic obstructive pulmonary disease. Questionnaires and scales have been used to assess limitations in ADL. The London Chest Activity of Daily Living (LCADL) scale is responsive to intervention to a higher extent when compared with other tools. However, the minimal detectable change (MDC) for this scale remains unknown. The aim of this study was to determine the MDC for functional status improvement measured by the LCADL scale in patients with chronic obstructive pulmonary disease. Forty patients (20 men, 66 ± 7 years, forced expired volume in 1 second 44 ± 16% predicted) participated in a 3-month high-intensity exercise training program. Before and after the protocol, participants complete the LCADL scale and the Saint George Respiratory Questionnaire. To calculate the MDC, we used the standard error of measurement and the effect size (distribution-based estimates). There was improvement in the LCADL self-care, domestic and leisure domains, and total score after the training program, with a strong trend for improvement in the physical activity domain. The MDC estimated for the LCADL were 0.89, 2.60, 0.44, 0.58, and 3.88 points for self-care, domestic, physical, and leisure domains, and total score, respectively. Correlations between changes in LCADL and in the Saint George Respiratory Questionnaire were weak (r < 0.4 for all). This study provided the MDC for the domains and total score of the LCADL. A change of 4 points in the total score of the LCADL can be interpreted as a meaningful change.

  8. Yeast Estrogen Screen Assay as a Tool for Detecting Estrogenic Activity in Water Bodies

    Directory of Open Access Journals (Sweden)

    Mirjana Bistan

    2012-01-01

    Full Text Available The presence of endocrine-disrupting compounds in wastewater, surface water, groundwater and even drinking water has become a major concern worldwide, since they negatively affect wildlife and humans. Therefore, these substances should be effectively removed from effluents before they are discharged into surface water to prevent pollution of groundwater, which can be a source of drinking water. Furthermore, an efficient control of endocrine-disrupting compounds in wastewater based on biological and analytical techniques is required. In this study, a yeast estrogen screen (YES bioassay has been introduced and optimized with the aim to assess potential estrogenic activity of waters. First, assay duration, concentration of added substrate to the assay medium and wavelength used to measure the absorbance of the substrate were estimated. Several compounds, such as 17-β-estradiol, 17-α-ethinylestradiol, bisphenol A, nonylphenol, genisteine, hydrocortisone, dieldrin, atrazine, methoxychlor, testosterone and progesterone were used to verify its specificity and sensitivity. The optimized YES assay was sensitive and responded specifically to the selected estrogenic and nonestrogenic compounds in aqueous samples. Potential estrogenicity of influent and effluent samples of two wastewater treatment plants was assessed after the samples had been concentrated by solid-phase extraction (SPE procedure using Oasis® HLB cartridges and methanol as eluting solvent. Up to 90 % of relative estrogenic activity was detected in concentrated samples of influents to wastewater treatment plants and estrogenic activity was still present in the concentrated effluent samples. We found that the introduced YES assay is a suitable screening tool for monitoring the potential estrogenicity of effluents that are discharged into surface water.

  9. Joint analysis of infrasound and seismic signals by cross wavelet transform: detection of Mt. Etna explosive activity

    Directory of Open Access Journals (Sweden)

    A. Cannata

    2013-06-01

    Full Text Available The prompt detection of explosive volcanic activity is crucial since this kind of activity can release copious amounts of volcanic ash and gases into the atmosphere, causing severe dangers to aviation. In this work, we show how the joint analysis of seismic and infrasonic data by wavelet transform coherence (WTC can be useful to detect explosive activity, significantly enhancing its recognition that is normally done by video cameras and thermal sensors. Indeed, the efficiency of these sensors can be reduced (or inhibited in the case of poor visibility due to clouds or gas plumes. In particular, we calculated the root mean square (RMS of seismic and infrasonic signals recorded at Mt. Etna during 2011. This interval was characterised by several episodes of lava fountains, accompanied by lava effusion, and minor strombolian activities. WTC analysis showed significantly high values of coherence between seismic and infrasonic RMS during explosive activity, with infrasonic and seismic series in phase with each other, hence proving to be sensitive to both weak and strong explosive activity. The WTC capability of automatically detecting explosive activity was compared with the potential of detection methods based on fixed thresholds of seismic and infrasonic RMS. Finally, we also calculated the cross correlation function between seismic and infrasonic signals, which showed that the wave types causing such seismo-acoustic relationship are mainly incident seismic and infrasonic waves, likely with a common source.

  10. Active and Passive Remote Sensing Data Time Series for Flood Detection and Surface Water Mapping

    Science.gov (United States)

    Bioresita, Filsa; Puissant, Anne; Stumpf, André; Malet, Jean-Philippe

    2017-04-01

    As a consequence of environmental changes surface waters are undergoing changes in time and space. A better knowledge of the spatial and temporal distribution of surface waters resources becomes essential to support sustainable policies and development activities. Especially because surface waters, are not only a vital sweet water resource, but can also pose hazards to human settlements and infrastructures through flooding. Floods are a highly frequent disaster in the world and can caused huge material losses. Detecting and mapping their spatial distribution is fundamental to ascertain damages and for relief efforts. Spaceborne Synthetic Aperture Radar (SAR) is an effective way to monitor surface waters bodies over large areas since it provides excellent temporal coverage and, all-weather day-and-night imaging capabilities. However, emergent vegetation, trees, wind or flow turbulence can increase radar back-scatter returns and pose problems for the delineation of inundated areas. In such areas, passive remote sensing data can be used to identify vegetated areas and support the interpretation of SAR data. The availability of new Earth Observation products, for example Sentinel-1 (active) and Sentinel-2 (passive) imageries, with both high spatial and temporal resolution, have the potential to facilitate flood detection and monitoring of surface waters changes which are very dynamic in space and time. In this context, the research consists of two parts. In the first part, the objective is to propose generic and reproducible methodologies for the analysis of Sentinel-1 time series data for floods detection and surface waters mapping. The processing chain comprises a series of pre-processing steps and the statistical modeling of the pixel value distribution to produce probabilistic maps for the presence of surface waters. Images pre-processing for all Sentinel-1 images comprise the reduction SAR effect like orbit errors, speckle noise, and geometric effects. A modified

  11. Active and passive infrared thermography applied to the detection and characterization of hidden defects in structure

    Science.gov (United States)

    Dumoulin, Jean

    2013-04-01

    Infrared thermography for Non Destructive Testing (NDT) has encountered a wide spreading this last 2 decades, in particular thanks to emergence on the market of low cost uncooled infrared camera. So, infrared thermography is not anymore a measurement technique limited to laboratory application. It has been more and more involved in civil engineering and cultural heritage applications, but also in many other domains, as indicated by numerous papers in the literature. Nevertheless, laboratory, measurements are done as much as possible in quite ideal conditions (good atmosphere conditions, known properties of materials, etc.), while measurement on real site requires to consider the influence of not controlled environmental parameters and additional unknown thermal properties. So, dedicated protocol and additional sensors are required for measurement data correction. Furthermore, thermal excitation is required to enhance the signature of defects in materials. Post-processing of data requires to take into account the protocol used for the thermal excitation and sometimes its nature to avoid false detection. This analysis step is based on signal and image processing tool and allows to carry out the detection. Characterization of anomalies detected at the previous step can be done by additional signal processing in particular for manufactured objects. The use of thermal modelling and inverse method allows to determine properties of the defective area. The present paper will first address a review of some protocols currently in use for field measurement with passive and/or active infrared measurements. Illustrations in various experiments carried out on civil engineering structure will be shown and discussed. In a second part, different post-processing approaches will be presented and discussed. In particular, a review of the most standard processing methods like Fast Fourier Analysis, Principal Components Analysis, Polynomial Decomposition, defect characterization using

  12. A Label Free Colorimetric Assay for the Detection of Active Botulinum Neurotoxin Type A by SNAP-25 Conjugated Colloidal Gold

    Directory of Open Access Journals (Sweden)

    Christopher Gwenin

    2013-08-01

    Full Text Available Botulinum neurotoxins are one of the most potent toxins known to man. Current methods of detection involve the quantification of the toxin but do not take into account the percentage of the toxin that is active. At present the assay used for monitoring the activity of the toxin is the mouse bioassay, which is lengthy and has ethical issues due to the use of live animals. This report demonstrates a novel assay that utilises the endopeptidase activity of the toxin to detect Botulinum neurotoxin in a pharmaceutical sample. The cleaving of SNAP-25 is monitored via UV-Visible spectroscopy with a limit of detection of 373 fg/mL and has been further developed into a high throughput method using a microplate reader detecting down to 600 fg/mL of active toxin. The results show clear differences between the toxin product and the placebo, which contains the pharmaceutical excipients human serum albumin and lactose, showing that the assay detects the active form of the toxin.

  13. Contrast-enhanced Ultrasound for Detection of Crohn's Disease Activity: Systematic Review and Meta-analysis.

    Science.gov (United States)

    Serafin, Zbigniew; Białecki, Marcin; Białecka, Agnieszka; Sconfienza, Luca Maria; Kłopocka, Maria

    2016-03-01

    Reports on imaging of active Crohn's disease (aCD) using contrast-enhanced ultrasound (CEUS) are encouraging. However, the statistical power of most published papers is limited due to the small size of the patient groups included. This study was performed to verify the diagnostic value of CEUS in detecting aCD. A systematic literature search was performed by two independent reviewers for articles on the test characteristics of CEUS for the identification of aCD. The quality of the analysed studies was evaluated using a quality assessment tool for diagnostic accuracy studies (QUADAS-2). Pooling was performed using a diagnostic random-effect model and bivariate analysis. Eight articles were included in the final analysis, with a total of 332 patients. There was no significant publication bias. Significant heterogeneity was found regarding CEUS methodology and sonographic definitions of aCD. In a bivariate analysis, pooled sensitivity was 0.94 (95% CI 0.87-0.97) and pooled specificity was 0.79 (95% CI 0.67-0.88). Spearman correlation statistics presented no significant diagnostic threshold effect (r = 0.12, p > 0.9). Subgroup analysis showed that relative intestine wall enhancement had the highest diagnostic value (area under the curve 94%), while the presence of enhancement and analysis of the slope were less useful (area under the curve 91 and 90%, respectively). CEUS presents good sensitivity and moderate specificity in the detection of the aCD. Large-scale randomized trials with quantitative evaluation of CEUS images are necessary to promote this technique in clinical practice. Copyright © 2015 European Crohn’s and Colitis Organisation (ECCO). Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  14. Abnormal Ventral and Dorsal Attention Network Activity During Single and Dual Target Detection in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Amy M. Jimenez

    2016-03-01

    Full Text Available Early visual perception and attention are impaired in schizophrenia, and these deficits can be observed on target detection tasks. These tasks activate distinct ventral and dorsal brain networks which support stimulus-driven and goal-directed attention, respectively. We used single and dual target rapid serial visual presentation (RSVP tasks during fMRI with an ROI approach to examine regions within these networks associated with target detection and the attentional blink (AB in 21 schizophrenia outpatients and 25 healthy controls. In both tasks, letters were targets and numbers were distractors. For the dual target task, the second target (T2 was presented at 3 different lags after the first target (T1 (lag1=100ms, lag3=300ms, lag7=700ms. For both single and dual target tasks, patients identified fewer targets than controls. For the dual target task, both groups showed the expected AB effect with poorer performance at lag 3 than at lags 1 or 7, and there was no group by lag interaction. During the single target task, patients showed abnormally increased deactivation of the temporo-parietal junction (TPJ, a key region of the ventral network. When attention demands were increased during the dual target task, patients showed overactivation of the posterior intraparietal cortex, a key dorsal network region, along with failure to deactivate TPJ. Results suggest inefficient and faulty suppression of salience-oriented processing regions, resulting in increased sensitivity to stimuli in general, and difficulty distinguishing targets from non-targets.

  15. New generation of monolithic active pixel sensors for charged particle detection

    International Nuclear Information System (INIS)

    Deptuch, G.

    2002-09-01

    Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a 55 Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 μm and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 10 12 n/cm 2 and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

  16. High-power, photofission-inducing bremsstrahlung source for intense pulsed active detection of fissile material

    Directory of Open Access Journals (Sweden)

    J. C. Zier

    2014-06-01

    Full Text Available Intense pulsed active detection (IPAD is a promising technique for detecting fissile material to prevent the proliferation of special nuclear materials. With IPAD, fissions are induced in a brief, intense radiation burst and the resulting gamma ray or neutron signals are acquired during a short period of elevated signal-to-noise ratio. The 8 MV, 200 kA Mercury pulsed-power generator at the Naval Research Laboratory coupled to a high-power vacuum diode produces an intense 30 ns bremsstrahlung beam to study this approach. The work presented here reports on Mercury experiments designed to maximize the photofission yield in a depleted-uranium (DU object in the bremsstrahlung far field by varying the anode-cathode (AK diode gap spacing and by adding an inner-diameter-reducing insert in the outer conductor wall. An extensive suite of diagnostics was fielded to measure the bremsstrahlung beam and DU fission yield as functions of diode geometry. Delayed fission neutrons from the DU proved to be a valuable diagnostic for measuring bremsstrahlung photons above 5 MeV. The measurements are in broad agreement with particle-in-cell and Monte Carlo simulations of electron dynamics and radiation transport. These show that with increasing AK gap, electron losses to the insert and outer conductor wall increase and that the electron angles impacting the bremsstrahlung converter approach normal incidence. The diode conditions for maximum fission yield occur when the gap is large enough to produce electron angles close to normal, yet small enough to limit electron losses.

  17. 3-D Electrochemical Impedance Spectroscopy Mapping of Arteries to Detect Metabolically Active but Angiographically Invisible Atherosclerotic Lesions.

    Science.gov (United States)

    Packard, René R Sevag; Luo, Yuan; Abiri, Parinaz; Jen, Nelson; Aksoy, Olcay; Suh, William M; Tai, Yu-Chong; Hsiai, Tzung K

    2017-01-01

    We designed a novel 6-point electrochemical impedance spectroscopy (EIS) sensor with 15 combinations of permutations for the 3-D mapping and detection of metabolically active atherosclerotic lesions. Two rows of 3 stretchable electrodes circumferentially separated by 120° were mounted on an inflatable balloon for intravascular deployment and endoluminal interrogation. The configuration and 15 permutations of 2-point EIS electrodes allowed for deep arterial penetration via alternating current (AC) to detect varying degrees of lipid burden with distinct impedance profiles (Ω). By virtue of the distinctive impedimetric signature of metabolically active atherosclerotic lesions, a detailed impedance map was acquired, with the 15 EIS permutations uncovering early stages of disease characterized by fatty streak lipid accumulation in the New Zealand White rabbit model of atherosclerosis. Both the equivalent circuit and statistical analyses corroborated the 3-D EIS permutations to detect small, angiographically invisible, lipid-rich lesions, with translational implications for early atherosclerotic disease detection and prevention of acute coronary syndromes or strokes.

  18. Oestrus Detection in Dairy Cows from Activity and Lying Data using on-line Individual Models

    DEFF Research Database (Denmark)

    Jónsson, Ragnar Ingi; Blanke, Mogens; Poulsen, Niels Kjølstad

    2011-01-01

    Automated monitoring and detection of oestrus in dairy cows is attractive for reasons of economy in dairy farming. While high performance detection has been shown possible using high-priced progesterone measurements, detection results were less reliable when only low-cost sensor data were availab...

  19. Role of digital tomosynthesis and dual energy subtraction digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Sharma, Madhurima; Sandhu, Manavjit Singh; Gorsi, Ujjwal; Gupta, Dheeraj; Khandelwal, Niranjan

    2015-01-01

    Highlights: • Digital tomosynthesis and dual energy subtraction digital radiography are modifications of digital radiography. • These modalities perform better than digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis. • Digital tomosynthesis has a sensitivity of 100% in detection of cavities. • Centrilobular nodules seen on CT in active pulmonary tuberculosis, were also demonstrated on digital tomosynthesis in our study. • Digital tomosynthesis can be used for diagnosis and follow up of patients in pulmonary tuberculosis, thereby reducing the number of CT examinations. - Abstract: Objective: To assess the role of digital tomosynthesis (DTS) and dual energy subtraction digital radiography (DES-DR) in detection of parenchymal lesions in active pulmonary tuberculosis (TB) and to compare them with digital radiography (DR). Materials and methods: This prospective study was approved by our institutional review committee. DTS and DES-DR were performed in 62 patients with active pulmonary TB within one week of multidetector computed tomography (MDCT) study. Findings of active pulmonary TB, that is consolidation, cavitation and nodules were noted on digital radiography (DR), DTS and DES-DR in all patients. Sensitivity, specificity, positive and negative predictive values of all 3 modalities was calculated with MDCT as reference standard. In addition presence of centrilobular nodules was also noted on DTS. Results: Our study comprised of 62 patients (33 males, 29 females with age range 18–82 years). Sensitivity and specificity of DTS for detection of nodules and cavitation was better than DR and DES-DR. Sensitivity and specificity of DTS for detection of consolidation was comparable to DR and DES-DR. DES-DR performed better than DR in detection of nodules and cavitation. DTS was also able to detect centrilobular nodules with sensitivity and specificity of 57.4% and 86.5% respectively. Conclusion: DTS and DES-DR perform better

  20. Role of digital tomosynthesis and dual energy subtraction digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Madhurima, E-mail: madhurimashrm88@gmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Sandhu, Manavjit Singh, E-mail: manavjitsandhu@yahoo.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Gorsi, Ujjwal, E-mail: ujjwalgorsi@gmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India); Gupta, Dheeraj, E-mail: dheeraj1910@gmail.com [Department of Pulmonary Medicine, PGIMER, Chandigarh 160012 (India); Khandelwal, Niranjan, E-mail: khandelwaln@hotmail.com [Department of Radiodiagnosis and Imaging, PGIMER, Chandigarh 160012 (India)

    2015-09-15

    Highlights: • Digital tomosynthesis and dual energy subtraction digital radiography are modifications of digital radiography. • These modalities perform better than digital radiography in detection of parenchymal lesions in active pulmonary tuberculosis. • Digital tomosynthesis has a sensitivity of 100% in detection of cavities. • Centrilobular nodules seen on CT in active pulmonary tuberculosis, were also demonstrated on digital tomosynthesis in our study. • Digital tomosynthesis can be used for diagnosis and follow up of patients in pulmonary tuberculosis, thereby reducing the number of CT examinations. - Abstract: Objective: To assess the role of digital tomosynthesis (DTS) and dual energy subtraction digital radiography (DES-DR) in detection of parenchymal lesions in active pulmonary tuberculosis (TB) and to compare them with digital radiography (DR). Materials and methods: This prospective study was approved by our institutional review committee. DTS and DES-DR were performed in 62 patients with active pulmonary TB within one week of multidetector computed tomography (MDCT) study. Findings of active pulmonary TB, that is consolidation, cavitation and nodules were noted on digital radiography (DR), DTS and DES-DR in all patients. Sensitivity, specificity, positive and negative predictive values of all 3 modalities was calculated with MDCT as reference standard. In addition presence of centrilobular nodules was also noted on DTS. Results: Our study comprised of 62 patients (33 males, 29 females with age range 18–82 years). Sensitivity and specificity of DTS for detection of nodules and cavitation was better than DR and DES-DR. Sensitivity and specificity of DTS for detection of consolidation was comparable to DR and DES-DR. DES-DR performed better than DR in detection of nodules and cavitation. DTS was also able to detect centrilobular nodules with sensitivity and specificity of 57.4% and 86.5% respectively. Conclusion: DTS and DES-DR perform better

  1. Monitoring cow activity and rumination time for an early detection of heat stress in dairy cow

    Science.gov (United States)

    Abeni, Fabio; Galli, Andrea

    2017-03-01

    The aim of this study was to explore the use of cow activity and rumination time by precision livestock farming tools as early alert for heat stress (HS) detection. A total of 58 Italian Friesian cows were involved in this study during summer 2015. Based on the temperature humidity index (THI), two different conditions were compared on 16 primiparous and 11 multiparous, to be representative of three lactation phases: early (15-84 DIM), around peak (85-154 DIM), and plateau (155-224 DIM). A separate dataset for the assessment of the variance partition included all the cows in the herd from June 7 to July 16. The rumination time (RT2h, min/2 h) and activity index (AI2h, bouts/2 h) were summarized every 2-h interval. The raw data were used to calculate the following variables: total daily RT (RTt), daytime RT (RTd), nighttime RT (RTn), total daily AI (AIt), daytime AI (AId), and nighttime AI (AIn). Either AIt and AId increased, whereas RTt, RTd, and RTn decreased with higher THI in all the three phases. The highest decrease was recorded for RTd and ranged from 49 % (early) to 45 % (plateau). The contribution of the cow within lactation phase was above 60 % of the total variance for AI traits and a share from 33.9 % (for RTt) to 54.8 % (RTn) for RT traits. These observations must be extended to different feeding managements and different animal genetics to assess if different thresholds could be identified to set an early alert system for the farmer.

  2. Peroxidase-like activity of nanocrystalline cobalt selenide and its application for uric acid detection

    Directory of Open Access Journals (Sweden)

    Zhuang QQ

    2017-04-01

    Full Text Available Quan-Quan Zhuang,1 Zhi-Hang Lin,1 Yan-Cheng Jiang,1 Hao-Hua Deng,2 Shao-Bin He,1,3 Li-Ting Su,4 Xiao-Qiong Shi,2 Wei Chen2 1Department of Pharmacy, Affiliated Quanzhou First Hospital of Fujian Medical University, Quanzhou, 2Department of Pharmaceutical Analysis, School of Pharmacy, Fujian Medical University, Fuzhou, 3Department of Pharmacy, Quanzhou Infectious Disease Hospital, 4Department of Pharmaceutical Analysis, Quanzhou Medical College, Quanzhou, People’s Republic of China Abstract: Dendrite-like cobalt selenide nanostructures were synthesized from cobalt and selenium powder precursors by a solvothermal method in anhydrous ethylenediamine. The as-prepared nanocrystalline cobalt selenide was found to possess peroxidase-like activity that could catalyze the reaction of peroxidase substrates in the presence of H2O2. A spectrophotometric method for uric acid (UA determination was developed based on the nanocrystalline cobalt selenide-catalyzed coupling reaction between N-ethyl-N-(3-sulfopropyl-3-methylaniline sodium salt and 4-aminoantipyrine (4-AAP in the presence of H2O2. Under optimum conditions, the absorbance was proportional to the concentration of UA over the range of 2.0–40 µM with a detection limit of 0.5 µM. The applicability of the proposed method has been validated by determination of UA in human serum samples with satisfactory results. Keywords: enzyme mimics, cobalt selenide, peroxidase-like activity, uric acid, human serum

  3. Linear Feature Projection-Based Sensory Event Detection from the Multiunit Activity of Dorsal Root Ganglion Recordings.

    Science.gov (United States)

    Han, Sungmin; Youn, Inchan

    2018-03-28

    Afferent signals recorded from the dorsal root ganglion can be used to extract sensory information to provide feedback signals in a functional electrical stimulation (FES) system. The goal of this study was to propose an efficient feature projection method for detecting sensory events from multiunit activity-based feature vectors of tactile afferent activity. Tactile afferent signals were recorded from the L4 dorsal root ganglion using a multichannel microelectrode for three types of sensory events generated by mechanical stimulation on the rat hind paw. The multiunit spikes (MUSs) were extracted as multiunit activity-based feature vectors and projected using a linear feature projection method which consisted of projection pursuit and negentropy maximization (PP/NEM). Finally, a multilayer perceptron classifier was used to detect sensory events. The proposed method showed a detection accuracy superior to those of other linear and nonlinear feature projection methods and all processes were completed within real-time constraints. Results suggest that the proposed method could be useful to detect sensory events in real time. We have demonstrated the methodology for an efficient feature projection method to detect real-time sensory events from the multiunit activity of dorsal root ganglion recordings. The proposed method could be applied to provide real-time sensory feedback signals in closed-loop FES systems.

  4. Active learning approach for detection of hard exudates, cotton wool spots, and drusen in retinal images

    Science.gov (United States)

    Sánchez, Clara I.; Niemeijer, Meindert; Kockelkorn, Thessa; Abràmoff, Michael D.; van Ginneken, Bram

    2009-02-01

    Computer-aided Diagnosis (CAD) systems for the automatic identification of abnormalities in retinal images are gaining importance in diabetic retinopathy screening programs. A huge amount of retinal images are collected during these programs and they provide a starting point for the design of machine learning algorithms. However, manual annotations of retinal images are scarce and expensive to obtain. This paper proposes a dynamic CAD system based on active learning for the automatic identification of hard exudates, cotton wool spots and drusen in retinal images. An uncertainty sampling method is applied to select samples that need to be labeled by an expert from an unlabeled set of 4000 retinal images. It reduces the number of training samples needed to obtain an optimum accuracy by dynamically selecting the most informative samples. Results show that the proposed method increases the classification accuracy compared to alternative techniques, achieving an area under the ROC curve of 0.87, 0.82 and 0.78 for the detection of hard exudates, cotton wool spots and drusen, respectively.

  5. Detection of low-energy antinuclei in space using an active-target particle detector

    Energy Technology Data Exchange (ETDEWEB)

    Poeschl, Thomas; Greenwald, Daniel; Konorov, Igor; Paul, Stephan [Physics Department E18, Technische Universitaet Muenchen (Germany); Losekamm, Martin [Physics Department E18, Technische Universitaet Muenchen (Germany); Institute of Astronautics, Technische Universitaet Muenchen (Germany)

    2015-07-01

    Measuring antimatter in space excellently probes various astrophysical processes. The abundances and energy spectra of antiparticles reveal a lot about the creation and propagation of cosmic-ray particles in the universe. Abnormalities in their spectra can reveal exotic sources or inaccuracies in our understanding of the involved processes. The measurement of antiprotons and the search for antideuterons and antihelium are optimal at low kinetic energies since background from high-energy cosmic-ray collisions is low. For this reason, we are developing an active-target particle detector capable of detecting ions and anti-ions in the energy range of 30-100 MeV per nucleon. The detector consists of 900 scintillating fibers coupled to silicon photomultipliers and is designed to operate on nanosatellites. The primary application of the detector will be the Antiproton Flux in Space (AFIS) mission, whose goal is the measurement of geomagnetically trapped antiprotons inside Earth's inner radiation belt. In this talk, we explain our particle identification technique and present results from first in-beam measurements with a prototype.

  6. Particle Filter with Integrated Voice Activity Detection for Acoustic Source Tracking

    Science.gov (United States)

    Lehmann, Eric A.; Johansson, Anders M.

    2006-12-01

    In noisy and reverberant environments, the problem of acoustic source localisation and tracking (ASLT) using an array of microphones presents a number of challenging difficulties. One of the main issues when considering real-world situations involving human speakers is the temporally discontinuous nature of speech signals: the presence of silence gaps in the speech can easily misguide the tracking algorithm, even in practical environments with low to moderate noise and reverberation levels. A natural extension of currently available sound source tracking algorithms is the integration of a voice activity detection (VAD) scheme. We describe a new ASLT algorithm based on a particle filtering (PF) approach, where VAD measurements are fused within the statistical framework of the PF implementation. Tracking accuracy results for the proposed method is presented on the basis of synthetic audio samples generated with the image method, whereas performance results obtained with a real-time implementation of the algorithm, and using real audio data recorded in a reverberant room, are published elsewhere. Compared to a previously proposed PF algorithm, the experimental results demonstrate the improved robustness of the method described in this work when tracking sources emitting real-world speech signals, which typically involve significant silence gaps between utterances.

  7. Voice Activity Detection Based on High Order Statistics and Online EM Algorithm

    Science.gov (United States)

    Cournapeau, David; Kawahara, Tatsuya

    A new online, unsupervised voice activity detection (VAD) method is proposed. The method is based on a feature derived from high-order statistics (HOS), enhanced by a second metric based on normalized autocorrelation peaks to improve its robustness to non-Gaussian noises. This feature is also oriented for discriminating between close-talk and far-field speech, thus providing a VAD method in the context of human-to-human interaction independent of the energy level. The classification is done by an online variation of the Expectation-Maximization (EM) algorithm, to track and adapt to noise variations in the speech signal. Performance of the proposed method is evaluated on an in-house data and on CENSREC-1-C, a publicly available database used for VAD in the context of automatic speech recognition (ASR). On both test sets, the proposed method outperforms a simple energy-based algorithm and is shown to be more robust against the change in speech sparsity, SNR variability and the noise type.

  8. UTOPIA NMR: activating unexploited magnetization using interleaved low-gamma detection

    Energy Technology Data Exchange (ETDEWEB)

    Viegas, Aldino; Viennet, Thibault [Heinrich-Heine-University, Institute of Physical Biology (Germany); Yu, Tsyr-Yan [Academia Sinica, Institute of Atomic and Molecular Sciences (China); Schumann, Frank [Bruker BioSpin GmbH (Switzerland); Bermel, Wolfgang [Bruker BioSpin GmbH (Germany); Wagner, Gerhard [Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology (United States); Etzkorn, Manuel, E-mail: manuel.etzkorn@hhu.de [Heinrich-Heine-University, Institute of Physical Biology (Germany)

    2016-01-15

    A growing number of nuclear magnetic resonance (NMR) spectroscopic studies are impaired by the limited information content provided by the standard set of experiments conventionally recorded. This is particularly true for studies of challenging biological systems including large, unstructured, membrane-embedded and/or paramagnetic proteins. Here we introduce the concept of unified time-optimized interleaved acquisition NMR (UTOPIA-NMR) for the unified acquisition of standard high-γ (e.g. {sup 1}H) and low-γ (e.g. {sup 13}C) detected experiments using a single receiver. Our aim is to activate the high level of polarization and information content distributed on low-γ nuclei without disturbing conventional magnetization transfer pathways. We show that using UTOPIA-NMR we are able to recover nearly all of the normally non-used magnetization without disturbing the standard experiments. In other words, additional spectra, that can significantly increase the NMR insights, are obtained for free. While we anticipate a broad range of possible applications we demonstrate for the soluble protein Bcl-x{sub L} (ca. 21 kDa) and for OmpX in nanodiscs (ca. 160 kDa) that UTOPIA-NMR is particularly useful for challenging protein systems including perdeuterated (membrane) proteins.

  9. UTOPIA NMR: activating unexploited magnetization using interleaved low-gamma detection

    International Nuclear Information System (INIS)

    Viegas, Aldino; Viennet, Thibault; Yu, Tsyr-Yan; Schumann, Frank; Bermel, Wolfgang; Wagner, Gerhard; Etzkorn, Manuel

    2016-01-01

    A growing number of nuclear magnetic resonance (NMR) spectroscopic studies are impaired by the limited information content provided by the standard set of experiments conventionally recorded. This is particularly true for studies of challenging biological systems including large, unstructured, membrane-embedded and/or paramagnetic proteins. Here we introduce the concept of unified time-optimized interleaved acquisition NMR (UTOPIA-NMR) for the unified acquisition of standard high-γ (e.g. 1 H) and low-γ (e.g. 13 C) detected experiments using a single receiver. Our aim is to activate the high level of polarization and information content distributed on low-γ nuclei without disturbing conventional magnetization transfer pathways. We show that using UTOPIA-NMR we are able to recover nearly all of the normally non-used magnetization without disturbing the standard experiments. In other words, additional spectra, that can significantly increase the NMR insights, are obtained for free. While we anticipate a broad range of possible applications we demonstrate for the soluble protein Bcl-x L (ca. 21 kDa) and for OmpX in nanodiscs (ca. 160 kDa) that UTOPIA-NMR is particularly useful for challenging protein systems including perdeuterated (membrane) proteins

  10. UTOPIA NMR: activating unexploited magnetization using interleaved low-gamma detection.

    Science.gov (United States)

    Viegas, Aldino; Viennet, Thibault; Yu, Tsyr-Yan; Schumann, Frank; Bermel, Wolfgang; Wagner, Gerhard; Etzkorn, Manuel

    2016-01-01

    A growing number of nuclear magnetic resonance (NMR) spectroscopic studies are impaired by the limited information content provided by the standard set of experiments conventionally recorded. This is particularly true for studies of challenging biological systems including large, unstructured, membrane-embedded and/or paramagnetic proteins. Here we introduce the concept of unified time-optimized interleaved acquisition NMR (UTOPIA-NMR) for the unified acquisition of standard high-γ (e.g. (1)H) and low-γ (e.g. (13)C) detected experiments using a single receiver. Our aim is to activate the high level of polarization and information content distributed on low-γ nuclei without disturbing conventional magnetization transfer pathways. We show that using UTOPIA-NMR we are able to recover nearly all of the normally non-used magnetization without disturbing the standard experiments. In other words, additional spectra, that can significantly increase the NMR insights, are obtained for free. While we anticipate a broad range of possible applications we demonstrate for the soluble protein Bcl-xL (ca. 21 kDa) and for OmpX in nanodiscs (ca. 160 kDa) that UTOPIA-NMR is particularly useful for challenging protein systems including perdeuterated (membrane) proteins.

  11. Particle Filter with Integrated Voice Activity Detection for Acoustic Source Tracking

    Directory of Open Access Journals (Sweden)

    Anders M. Johansson

    2007-01-01

    Full Text Available In noisy and reverberant environments, the problem of acoustic source localisation and tracking (ASLT using an array of microphones presents a number of challenging difficulties. One of the main issues when considering real-world situations involving human speakers is the temporally discontinuous nature of speech signals: the presence of silence gaps in the speech can easily misguide the tracking algorithm, even in practical environments with low to moderate noise and reverberation levels. A natural extension of currently available sound source tracking algorithms is the integration of a voice activity detection (VAD scheme. We describe a new ASLT algorithm based on a particle filtering (PF approach, where VAD measurements are fused within the statistical framework of the PF implementation. Tracking accuracy results for the proposed method is presented on the basis of synthetic audio samples generated with the image method, whereas performance results obtained with a real-time implementation of the algorithm, and using real audio data recorded in a reverberant room, are published elsewhere. Compared to a previously proposed PF algorithm, the experimental results demonstrate the improved robustness of the method described in this work when tracking sources emitting real-world speech signals, which typically involve significant silence gaps between utterances.

  12. Endothelial Cell-derived Extracellular Vesicles Size-dependently Exert Procoagulant Activity Detected by Thromboelastometry.

    Science.gov (United States)

    Holnthoner, Wolfgang; Bonstingl, Cornelia; Hromada, Carina; Muehleder, Severin; Zipperle, Johannes; Stojkovic, Stefan; Redl, Heinz; Wojta, Johann; Schöchl, Herbert; Grillari, Johannes; Weilner, Sylvia; Schlimp, Christoph J

    2017-06-16

    Endothelial cells (ECs) are major modulators of hemostasis by expressing and releasing pro- and anticoagulant mediators into the circulation. Previous studies showed that cultured ECs release procoagulant mediators into cell culture supernatants as evidenced by the reduction of viscoelastic clotting time. This effect was reversed with an anti-tissue factor antibody. Here, we aimed to investigate whether tissue factor (TF) was released by endothelial-derived extracellular vesicles (EVs) and which portion of the released vesicles displays the most prominent procoagulant properties. After stimulation of ECs with tumor-necrosis factor-α (TNF-α) the supernatants of EC cultures were subjected to differential centrifugation steps to collect larger and smaller EVs which were then characterised by nanoparticle tracking analysis (NTA) and flow cytometry. Mixed with fresh human blood and analysed by thromboelastometry EVs exerted a significant procoagulant stimulus, which could be partly reversed by addition of an anti-TF antibody. Moreover, TF activity was confirmed in the centrifuged fractions. In summary, our results provide evidence of the procoagulant potential of smaller and larger endothelial-derived EV fractions detected by thromboelastometry. The observed effect is most likely due to the release of TF-bearing EVs of different dimensions, which are released upon TNF-α stimulation of endothelial cell cultures.

  13. Design of an Active Multispectral SWIR Camera System for Skin Detection and Face Verification

    Directory of Open Access Journals (Sweden)

    Holger Steiner

    2016-01-01

    Full Text Available Biometric face recognition is becoming more frequently used in different application scenarios. However, spoofing attacks with facial disguises are still a serious problem for state of the art face recognition algorithms. This work proposes an approach to face verification based on spectral signatures of material surfaces in the short wave infrared (SWIR range. They allow distinguishing authentic human skin reliably from other materials, independent of the skin type. We present the design of an active SWIR imaging system that acquires four-band multispectral image stacks in real-time. The system uses pulsed small band illumination, which allows for fast image acquisition and high spectral resolution and renders it widely independent of ambient light. After extracting the spectral signatures from the acquired images, detected faces can be verified or rejected by classifying the material as “skin” or “no-skin.” The approach is extensively evaluated with respect to both acquisition and classification performance. In addition, we present a database containing RGB and multispectral SWIR face images, as well as spectrometer measurements of a variety of subjects, which is used to evaluate our approach and will be made available to the research community by the time this work is published.

  14. An ex ante analysis on the use of activity meters for automated estrus detection: to invest or not to invest?

    Science.gov (United States)

    Rutten, C J; Steeneveld, W; Inchaisri, C; Hogeveen, H

    2014-11-01

    The technical performance of activity meters for automated detection of estrus in dairy farming has been studied, and such meters are already used in practice. However, information on the economic consequences of using activity meters is lacking. The current study analyzes the economic benefits of a sensor system for detection of estrus and appraises the feasibility of an investment in such a system. A stochastic dynamic simulation model was used to simulate reproductive performance of a dairy herd. The number of cow places in this herd was fixed at 130. The model started with 130 randomly drawn cows (in a Monte Carlo process) and simulated calvings and replacement of these cows in subsequent years. Default herd characteristics were a conception rate of 50%, an 8-wk dry-off period, and an average milk production level of 8,310 kg per cow per 305 d. Model inputs were derived from real farm data and expertise. For the analysis, visual detection by the farmer ("without" situation) was compared with automated detection with activity meters ("with" situation). For visual estrus detection, an estrus detection rate of 50% and a specificity of 100% were assumed. For automated estrus detection, an estrus detection rate of 80% and a specificity of 95% were assumed. The results of the cow simulation model were used to estimate the difference between the annual net cash flows in the "with" and "without" situations (marginal financial effect) and the internal rate of return (IRR) as profitability indicators. The use of activity meters led to improved estrus detection and, therefore, to a decrease in the average calving interval and subsequent increase in annual milk production. For visual estrus detection, the average calving interval was 419 d and average annual milk production was 1,032,278 kg. For activity meters, the average calving interval was 403 d and the average annual milk production was 1,043,398 kg. It was estimated that the initial investment in activity meters

  15. Evaluation of Feature Extraction and Recognition for Activity Monitoring and Fall Detection Based on Wearable sEMG Sensors.

    Science.gov (United States)

    Xi, Xugang; Tang, Minyan; Miran, Seyed M; Luo, Zhizeng

    2017-05-27

    As an essential subfield of context awareness, activity awareness, especially daily activity monitoring and fall detection, plays a significant role for elderly or frail people who need assistance in their daily activities. This study investigates the feature extraction and pattern recognition of surface electromyography (sEMG), with the purpose of determining the best features and classifiers of sEMG for daily living activities monitoring and fall detection. This is done by a serial of experiments. In the experiments, four channels of sEMG signal from wireless, wearable sensors located on lower limbs are recorded from three subjects while they perform seven activities of daily living (ADL). A simulated trip fall scenario is also considered with a custom-made device attached to the ankle. With this experimental setting, 15 feature extraction methods of sEMG, including time, frequency, time/frequency domain and entropy, are analyzed based on class separability and calculation complexity, and five classification methods, each with 15 features, are estimated with respect to the accuracy rate of recognition and calculation complexity for activity monitoring and fall detection. It is shown that a high accuracy rate of recognition and a minimal calculation time for daily activity monitoring and fall detection can be achieved in the current experimental setting. Specifically, the Wilson Amplitude (WAMP) feature performs the best, and the classifier Gaussian Kernel Support Vector Machine (GK-SVM) with Permutation Entropy (PE) or WAMP results in the highest accuracy for activity monitoring with recognition rates of 97.35% and 96.43%. For fall detection, the classifier Fuzzy Min-Max Neural Network (FMMNN) has the best sensitivity and specificity at the cost of the longest calculation time, while the classifier Gaussian Kernel Fisher Linear Discriminant Analysis (GK-FDA) with the feature WAMP guarantees a high sensitivity (98.70%) and specificity (98.59%) with a short

  16. Evaluation of Feature Extraction and Recognition for Activity Monitoring and Fall Detection Based on Wearable sEMG Sensors

    Directory of Open Access Journals (Sweden)

    Xugang Xi

    2017-05-01

    Full Text Available As an essential subfield of context awareness, activity awareness, especially daily activity monitoring and fall detection, plays a significant role for elderly or frail people who need assistance in their daily activities. This study investigates the feature extraction and pattern recognition of surface electromyography (sEMG, with the purpose of determining the best features and classifiers of sEMG for daily living activities monitoring and fall detection. This is done by a serial of experiments. In the experiments, four channels of sEMG signal from wireless, wearable sensors located on lower limbs are recorded from three subjects while they perform seven activities of daily living (ADL. A simulated trip fall scenario is also considered with a custom-made device attached to the ankle. With this experimental setting, 15 feature extraction methods of sEMG, including time, frequency, time/frequency domain and entropy, are analyzed based on class separability and calculation complexity, and five classification methods, each with 15 features, are estimated with respect to the accuracy rate of recognition and calculation complexity for activity monitoring and fall detection. It is shown that a high accuracy rate of recognition and a minimal calculation time for daily activity monitoring and fall detection can be achieved in the current experimental setting. Specifically, the Wilson Amplitude (WAMP feature performs the best, and the classifier Gaussian Kernel Support Vector Machine (GK-SVM with Permutation Entropy (PE or WAMP results in the highest accuracy for activity monitoring with recognition rates of 97.35% and 96.43%. For fall detection, the classifier Fuzzy Min-Max Neural Network (FMMNN has the best sensitivity and specificity at the cost of the longest calculation time, while the classifier Gaussian Kernel Fisher Linear Discriminant Analysis (GK-FDA with the feature WAMP guarantees a high sensitivity (98.70% and specificity (98.59% with a

  17. Partial antiviral activities detection of chicken Mx jointing with neuraminidase gene (NA against Newcastle disease virus.

    Directory of Open Access Journals (Sweden)

    Yani Zhang

    Full Text Available As an attempt to increase the resistance to Newcastle Disease Virus (NDV and so further reduction of its risk on the poultry industry. This work aimed to build the eukaryotic gene co-expression plasmid of neuraminidase (NA gene and myxo-virus resistance (Mx and detect the gene expression in transfected mouse fibroblasts (NIH-3T3 cells, it is most important to investigate the influence of the recombinant plasmid on the chicken embryonic fibroblasts (CEF cells. cDNA fragment of NA and mutant Mx gene were derived from pcDNA3.0-NA and pcDNA3.0-Mx plasmid via PCR, respectively, then NA and Mx cDNA fragment were inserted into the multiple cloning sites of pVITRO2 to generate the eukaryotic co-expression plasmid pVITRO2-Mx-NA. The recombinant plasmid was confirmed by restriction endonuclease treatment and sequencing, and it was transfected into the mouse fibroblasts (NIH-3T3 cells. The expression of genes in pVITRO2-Mx-NA were measured by RT-PCR and indirect immunofluorescence assay (IFA. The recombinant plasmid was transfected into CEF cells then RT-PCR and the micro-cell inhibition tests were used to test the antiviral activity for NDV. Our results showed that co-expression vector pVITRO2-Mx-NA was constructed successfully; the expression of Mx and NA could be detected in both NIH-3T3 and CEF cells. The recombinant proteins of Mx and NA protect CEF cells from NDV infection until after 72 h of incubation but the individually mutagenic Mx protein or NA protein protects CEF cells from NDV infection till 48 h post-infection, and co-transfection group decreased significantly NDV infection compared with single-gene transfection group (P<0. 05, indicating that Mx-NA jointing contributed to delaying the infection of NDV in single-cell level and the co-transfection of the jointed genes was more powerful than single one due to their synergistic effects.

  18. Infrared thermography, a new method for detection of brown adipose tissue activity after a meal in humans

    Science.gov (United States)

    Habek, Nikola; Kordić, Milan; Jurenec, Franjo; Dugandžić, Aleksandra

    2018-03-01

    The activation of brown adipose tissue (BAT) after cold exposure leads to heat production. However, the activation of BAT activity after a meal as part of diet induced thermogenesis is still controversial. A possible reason is that measuring BAT activity by positron emission tomography-computed tomography (PET CT) via accumulation of radiotracer fludeoxyglucose (18F-FDG), which competes with an increase in glucose concentration after a meal, fails as the method of choice. In this study, activity of BAT was determined by infrared thermography. Activation of BAT 30 min after a meal increases glucose consumption, decreases plasma glucose concentration, and leads to changes of body temperature (diet-induced thermogenesis). Detecting pathophysiological changes in BAT activity after a meal by infrared thermography, a non-invasive more sensitive method, will be of great importance for people with increased body weight and diabetes mellitus type 2.

  19. Detection of chitinase activity by 2-aminobenzoic acid labeling of chito-oligosaccharides.

    Science.gov (United States)

    Ghauharali-van der Vlugt, Karen; Bussink, Anton P; Groener, Johanna E M; Boot, Rolf G; Aerts, Johannes M F G

    2009-01-01

    Chitinases are hydrolases capable of hydrolyzing the abundant natural polysaccharide chitin. Next to artificial fluorescent substrates, more physiological chito-oligomers are commonly used in chitinase assays. Analysis of chito-oligosaccharides products is generally accomplished by UV detection. However, the relatively poor sensitivity poses a serious limitation. Here we report on a novel, much more sensitive assay for the detection of chito-oligosaccharide reaction products released by chitinases, based on fluorescent detection, following chemical labeling by 2-aminobenzoic acid. Comparison with existing UV-based assays, shows that the novel assay offers the same advantages yet allows detection of chito-oligosaccharides in the low picomolar range.

  20. Joint Wavelet Video Denoising and Motion Activity Detection in Multimodal Human Activity Analysis: Application to Video-Assisted Bioacoustic/Psychophysiological Monitoring

    Directory of Open Access Journals (Sweden)

    G. V. Papanikolaou

    2007-12-01

    Full Text Available The current work focuses on the design and implementation of an indoor surveillance application for long-term automated analysis of human activity, in a video-assisted biomedical monitoring system. Video processing is necessary to overcome noise-related problems, caused by suboptimal video capturing conditions, due to poor lighting or even complete darkness during overnight recordings. Modified wavelet-domain spatiotemporal Wiener filtering and motion-detection algorithms are employed to facilitate video enhancement, motion-activity-based indexing and summarization. Structural aspects for validation of the motion detection results are also used. The proposed system has been already deployed in monitoring of long-term abdominal sounds, for surveillance automation, motion-artefacts detection and connection with other psychophysiological parameters. However, it can be used to any video-assisted biomedical monitoring or other surveillance application with similar demands.

  1. Critical review for the determination of the minimum detectable activity (MDA) of alpha-emitter radionuclides in environmental samples

    International Nuclear Information System (INIS)

    Gasco, C.; Anton, M.P.

    1996-12-01

    Different criteria for the calculation of the Minimum Detectable Activity (MDA) of an alpha emitter in environmental levels are reviewed in this report. Practical examples of its application to previously analyzed samples are shown. The authors propose a criteria based on prior calculations that applies to the radiochemical activities performed in the laboratory. The calculation procedure has been discussed with scientist from other laboratories in order to establish a general criteria to calculate the MDA

  2. Robust Mpc for Actuator–Fault Tolerance Using Set–Based Passive Fault Detection and Active Fault Isolation

    Directory of Open Access Journals (Sweden)

    Xu Feng

    2017-03-01

    Full Text Available In this paper, a fault-tolerant control (FTC scheme is proposed for actuator faults, which is built upon tube-based model predictive control (MPC as well as set-based fault detection and isolation (FDI. In the class of MPC techniques, tubebased MPC can effectively deal with system constraints and uncertainties with relatively low computational complexity compared with other robust MPC techniques such as min-max MPC. Set-based FDI, generally considering the worst case of uncertainties, can robustly detect and isolate actuator faults. In the proposed FTC scheme, fault detection (FD is passive by using invariant sets, while fault isolation (FI is active by means of MPC and tubes. The active FI method proposed in this paper is implemented by making use of the constraint-handling ability of MPC to manipulate the bounds of inputs.

  3. Research and Development of Monolithic Active Pixel Sensors for the Detection of the Elementary Particles

    International Nuclear Information System (INIS)

    Li, Y.

    2007-09-01

    In order to develop high spatial resolution and readout speed vertex detectors for the future International Linear Collider (ILC), fast CMOS Monolithic Active Pixel Sensors (MAPS) are studied on this work. Two prototypes of MAPS, MIMOSA 8 and MIMOSA 16, based on the same micro-electronic architecture were developed in CMOS processes with different thickness of epitaxial layer. The size of pixel matrix is 32 x 128: 8 columns of the pixel array are readout directly with analog outputs and the other 24 columns are connected to the column level auto-zero discriminators. The Correlated Double Sampling (CDS) structures are successfully implemented inside pixel and discriminator. The photo diode type pixels with different diode sizes are used in these prototypes. With a 55 Fe X-ray radioactive source, the important parameters, such as Temporal Noise, Fixed Pattern Noise (FPN), Signal-to-Noise Ratio (SNR), Charge-to-Voltage conversion Factor (CVF) and Charge Collection Efficiency (CCE), are studied as function of readout speed and diode size. For MIMOSA 8, the effect of fast neutrons irradiation is also. Two beam tests campaigns were made: at DESY with a 5 GeV electrons beam and at CERN with a 180 GeV pions beam. Detection Efficiency and Spatial Resolution are studied in function of the discriminator threshold. For these two parameters, the influences of diode size and SNR of the central pixel of a cluster are also discussed. In order to improve the spatial resolution of the digital outputs, a very compact (25 μm x 1 mm) and low consumption (300 μW) column level ADC is designed in AMS 0.35 μm OPTO process. Based on successive approximation architecture, the auto-offset cancellation structure is integrated. A new column level auto-zero discriminator using static latch is also designed. (author)

  4. Adverse events in critical care: Search and active detection through the Trigger Tool.

    Science.gov (United States)

    Molina, Francisco J; Rivera, Paula T; Cardona, Alejandro; Restrepo, Diana C; Monroy, Oralia; Rodas, Daniel; Barrientos, Juan G

    2018-02-04

    To investigate the incidence of disadvantageous events by using the Global Trigger Tool in an intensive care unit (ICU). A retrospective descriptive study was performed in a 12-bed university ICU in the city of Medellin, Colombia. Clinical charts of hospitalized patients were reviewed, between January 1 and December 31, 2016, with the following inclusion criteria: subjects aged over 18 years, with at least 24 h of hospitalization and who had a complete medical history that could be accessed. Interventions: Trained reviewers conducted a retrospective examination of medical charts searching for clue events that elicit investigation, in order to detect an unfavorable event. Measurements: Information was processed through SPSS software version 21; for numerical variables, the mean was reported with standard deviation (SD). Percentages were calculated for qualitative variables. Two hundred and forty-four triggers occurred, with 82.4% of subjects having presented with at least one and an average of 3.37 (SD 3.47). A total of 178 adverse events (AEs) took place in 48 individuals, with an incidence of 52.1%. On average, four events per patient were recorded, and for each unfortunate event, 1.98 triggers were presented. The most frequent displeasing issues were: pressure ulcers (17.6%), followed by complications or reactions to medical devices (4.3%), and lacerations or skin defects (3.7%); the least frequent was delayed diagnosis or treatment (0.56%). Thirty-eight point four percent of mishap events caused temporary damage that required intervention, and 48.9% of AEs were preventable. Comparison between AEs and admission diagnoses found that hypertension and sepsis were the only diagnoses that had statistical significance ( P = 0.042 and 0.022, respectively). Almost half of the unfavorable issues were classified as avoidable, which leaves a very wide field of work in terms of preventative activities.

  5. Active pharmaceutical ingredients detected in herbal food supplements for weight loss sampled on the Dutch market.

    Science.gov (United States)

    Reeuwijk, Noortje M; Venhuis, Bastiaan J; de Kaste, Dries; Hoogenboom, Ron L A P; Rietjens, Ivonne M C M; Martena, Martijn J

    2014-01-01

    Herbal food supplements claiming to reduce weight may contain active pharmacological ingredients (APIs) that can be used for the treatment of overweight and obesity. The aim of this study was to determine whether herbal food supplements for weight loss on the Dutch market contain APIs with weight loss properties. Herbal food supplements intended for weight loss (n = 50) were sampled from August 2004 to May 2013. An HPLC-DAD-MS/MS method was used to screen for the presence of the APIs in herbal supplements. In 24 samples the APIs sibutramine, desmethylsibutramine (DMS), didesmethylsibutramine (DDMS), rimonabant, sildenafil and/or the laxative phenolphthalein were identified 41 times. The presence of these APIs was, however, not stated on the label. The potential pharmacological effects of the detected APIs were estimated using data from reported effective doses of approved drugs. Use of 20 of the 24 herbal food supplements may result in potential pharmacological effects. Furthermore, risk assessment of phenolphthalein, a suspected carcinogen and found to be present in 10 supplements, based on the margin of exposure (MOE) approach, resulted in MOE values of 96-30,000. MOE values lower than 10,000 (96-220) were calculated for the daily intake levels of four out of these 10 supplements in which phenolphthalein was found. However, taking into account that weight loss preparations may be used for only a few weeks or months rather than during a lifetime, MOE values may be two to three orders of magnitude higher. The current study shows that the use of food supplements with sibutramine, DMS, DDMS and/or phenolphthalein could result in pharmacological effects.

  6. Electrochemical flow injection analysis of hydrazine in an excess of an active pharmaceutical ingredient: achieving pharmaceutical detection limits electrochemically.

    Science.gov (United States)

    Channon, Robert B; Joseph, Maxim B; Bitziou, Eleni; Bristow, Anthony W T; Ray, Andrew D; Macpherson, Julie V

    2015-10-06

    The quantification of genotoxic impurities (GIs) such as hydrazine (HZ) is of critical importance in the pharmaceutical industry in order to uphold drug safety. HZ is a particularly intractable GI and its detection represents a significant technical challenge. Here, we present, for the first time, the use of electrochemical analysis to achieve the required detection limits by the pharmaceutical industry for the detection of HZ in the presence of a large excess of a common active pharmaceutical ingredient (API), acetaminophen (ACM) which itself is redox active, typical of many APIs. A flow injection analysis approach with electrochemical detection (FIA-EC) is utilized, in conjunction with a coplanar boron doped diamond (BDD) microband electrode, insulated in an insulating diamond platform for durability and integrated into a two piece flow cell. In order to separate the electrochemical signature for HZ such that it is not obscured by that of the ACM (present in excess), the BDD electrode is functionalized with Pt nanoparticles (NPs) to significantly shift the half wave potential for HZ oxidation to less positive potentials. Microstereolithography was used to fabricate flow cells with defined hydrodynamics which minimize dispersion of the analyte and optimize detection sensitivity. Importantly, the Pt NPs were shown to be stable under flow, and a limit of detection of 64.5 nM or 0.274 ppm for HZ with respect to the ACM, present in excess, was achieved. This represents the first electrochemical approach which surpasses the required detection limits set by the pharmaceutical industry for HZ detection in the presence of an API and paves the wave for online analysis and application to other GI and API systems.

  7. Early Detection of Physical Activity for People With Type 1 Diabetes Mellitus.

    Science.gov (United States)

    Dasanayake, Isuru S; Bevier, Wendy C; Castorino, Kristin; Pinsker, Jordan E; Seborg, Dale E; Doyle, Francis J; Dassau, Eyal

    2015-06-30

    Early detection of exercise in individuals with type 1 diabetes mellitus (T1DM) may allow changes in therapy to prevent hypoglycemia. Currently there is limited experience with automated methods that detect the onset and end of exercise in this population. We sought to develop a novel method to quickly and reliably detect the onset and end of exercise in these individuals before significant changes in blood glucose (BG) occur. Sixteen adults with T1DM were studied as outpatients using a diary, accelerometer, heart rate monitor, and continuous glucose monitor for 2 days. These data were used to develop a principal component analysis based exercise detection method. Subjects also performed 60 and 30 minute exercise sessions at 30% and 50% predicted heart rate reserve (HRR), respectively. The detection method was applied to the exercise sessions to determine how quickly the detection of start and end of exercise occurred relative to change in BG. Mild 30% HRR and moderate 50% HRR exercise onset was identified in 6 ± 3 and 5 ± 2 (mean ± SD) minutes, while completion was detected in 3 ± 8 and 6 ± 5 minutes, respectively. BG change from start of exercise to detection time was 1 ± 6 and -1 ± 3 mg/dL, and, from the end of exercise to detection time was 6 ± 4 and -17 ± 13 mg/dL, respectively, for the 2 exercise sessions. False positive and negative ratios were 4 ± 2% and 21 ± 22%. The novel method for exercise detection identified the onset and end of exercise in approximately 5 minutes, with an average BG change of only -6 mg/dL. © 2015 Diabetes Technology Society.

  8. Active acoustic leak detection for LMFBR steam generator. Pt. 5. Experiment for detection of bubbles using the SG full sector model

    International Nuclear Information System (INIS)

    Kumagai, Hiromichi

    1997-01-01

    In order to prevent the expansion of tube damages and to maintain structural safety in steam generators (SG) of fast breeder reactors (FBR), it is necessary to detect precisely and immediately the leakage of water from tubes of heat exchangers. Therefore, an active acoustic method, which detects the sound attenuation due to bubbles generated in the sodium-water reactions, it being developed. In this paper, the attenuation characteristics of sound attenuated by bubbles and influence of background noise are investigated experimentally by using an SG full sector model (diameter ratio about 1/1, height ratio about 1/7) simulating the actual SG. As an experimental result, the received sound attenuation for ten seconds was more than 10 dB from air bubble injection when injected bubble of 10 l/s (equivalence water leak rate about 10 g/s). The attenuation of sound are least affected by bubble injection position of heat exchanger tube bunch department. And the time was about 25 seconds till the sound attenuation became 10 dB in case of quantity of air bubble 1 l/s (equivalent water leak rate about 1 g/s). It is clarified that the background noise hardly influenced water leak detection performance as a result of having examined influence of background noise. (author)

  9. Ratiometric detection of copper ions and alkaline phosphatase activity based on semiconducting polymer dots assembled with rhodamine B hydrazide.

    Science.gov (United States)

    Sun, Junyong; Mei, Han; Gao, Feng

    2017-05-15

    The rational surface functionalization of semiconducting polymer dots (Pdots) has attracted much attention to extend their applications in fabricating chemo/biosensing platform. In this study, a novel ratiometric fluorescent sensing platform using functionalized Pdots as probes for fluorescence signal transmission has been designed for sensing Cu(Ⅱ) and activity of alkaline phosphatase (ALP) with high selectivity and enhanced sensitivity. The highly fluorescent Pdots were firstly prepared with Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadiazole)] (PFBT) via nanoprecipitation method, and then assembled with non-fluorescent rhodamine B hydrazide (RB-hy), which shows special binding activity to Cu(Ⅱ), through adsorption process to obtain functionalized nanohybrids, Pdots@RB-hy. As thus, a FRET donors/acceptors pair, in which PFBT Pdots act as energy donors while RB-hy-Cu(II) complexes act as energy acceptors were constructed. On the basis of the varies in fluorescence intensities of donors/acceptors in the presence of different amounts of Cu(II), a ratiometric method for sensing Cu(II) has been proposed. The proposed ratiometric Cu(II) sensor shows a good linear detection range from 0.05 to 5μM with a detection limit of 15nM. Furthermore, using the Pdots@RB-hy-Cu(II) system as signal transducer, a ratiometric sensing for alkaline phosphatase (ALP) activity has also been established with pyrophosphate (PPi) as substrates. The constructed ratiometric sensor of ALP activity displays a linear detection range from 0.005 to 15UL -1 with a detection limit of 0.0018UL -1 . The sensor was further successfully used for ALP activity detection in human serum with satisfactory results. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Non-target activity detection by post-radioembolization yttrium-90 PET/CT: Image assessment technique and case examples

    Directory of Open Access Journals (Sweden)

    Yung Hsiang eKao

    2014-02-01

    Full Text Available High-resolution yttrium-90 (90Y imaging of post-radioembolization microsphere biodistribution may be achieved by conventional positron emission tomography with integrated computed tomography (PET/CT scanners that have time-of-flight capability. However, reconstructed 90Y PET/CT images have high background noise, making non-target activity detection technically challenging. This educational article describes our image assessment technique for non-target activity detection by 90Y PET/CT which qualitatively overcomes the problem of background noise. We present selected case examples of non-target activity in untargeted liver, stomach, gallbladder, chest wall and kidney, supported by angiography and 90Y bremsstrahlung single photon emission computed tomography with integrated computed tomography (SPECT/CT or technetium-99m macroaggregated albumin SPECT/CT.

  11. Controlling the false positive rate in fuzzy clustering using randomization: application to fMRI activation detection.

    Science.gov (United States)

    Jahanian, Hesamoddin; Hossein-Zadeh, Gholam-Ali; Soltanian-Zadeh, Hamid; Ardekani, Babak A

    2004-06-01

    Despite its potential advantages for fMRI analysis, fuzzy C-means (FCM) clustering suffers from limitations such as the need for a priori knowledge of the number of clusters, and unknown statistical significance and instability of the results. We propose a randomization-based method to control the false-positive rate and estimate statistical significance of the FCM results. Using this novel approach, we develop an fMRI activation detection method. The ability of the method in controlling the false-positive rate is shown by analysis of false positives in activation maps of resting-state fMRI data. Controlling the false-positive rate in FCM allows comparison of different fuzzy clustering methods, using different feature spaces, to other fMRI detection methods. In this article, using simulation and real fMRI data, we compare a novel feature space that takes the variability of the hemodynamic response function into account (HRF-based feature space) to the conventional cross-correlation analysis and FCM using the cross-correlation feature space. In both cases, the HRF-based feature space provides a greater sensitivity compared to the cross-correlation feature space and conventional cross-correlation analysis. Application of the proposed method to finger-tapping fMRI data, using HRF-based feature space, detected activation in sub-cortical regions, whereas both of the FCM with cross-correlation feature space and the conventional cross-correlation method failed to detect them.

  12. A BIC Based Initial Training Set Selection Algorithm for Active Learning and Its Application in Audio Detection

    Directory of Open Access Journals (Sweden)

    Y. Leng

    2013-06-01

    Full Text Available To construct a classification system or a detection system, large amounts of labeled samples are needed. However, manual labeling is dull and time consuming, so researchers have proposed the active learning technology. The initial training set selection is the first step of an active learning process, but currently there have been few studies on it. Most active learning algorithms adopt random sampling or algorithms like sampling by clustering (SBC to select the initial training samples. But these two kinds of method would lose their effectiveness in detecting events of small probability. Because sometimes they could not select or select too few samples of the small probability events. To solve this problem, this paper proposes a BIC based initial training set selection algorithm. The BIC based algorithm performs clustering on the whole training set first. Then uses BIC to judge the status of clusters. Finally, it adopts different selection strategies for clusters of different status. Experimental results on two real data sets show that, compared to random sampling and SBC, the proposed BIC based initial training set selection algorithm can efficiently solve the detection problem of small probability events. In the mean time, it has obvious advantages in detecting events of non-small probability.

  13. Improving Air Force Active Network Defense Systems through an Analysis of Intrusion Detection Techniques

    National Research Council Canada - National Science Library

    Dunklee, David R

    2007-01-01

    .... The research then presents four recommendations to improve DCC operations. These include: Transition or improve the current signature-based IDS systems to include the capability to query and visualize network flows to detect malicious traffic...

  14. Multigradient Field Active Contour for Multilayer Detection of Ultrasound Rectal Wall Image

    National Research Council Canada - National Science Library

    Xiao, Di

    2001-01-01

    .... One of the aims is to apply this technique for multilayer boundary detection of ultrasound rectal wall image, which is important in colorectal clinical diagnosis for rectal tumor staging The core...

  15. Thyroid Histopathology Assessments for the Amphibian Metamorphosis Assay to Detect Thyroid-active Substances

    Science.gov (United States)

    In support of an Organization for Economic Cooperation and Development (OECD) Amphibian Metamorphosis Assay (AMA) Test Guideline for the detection of substances that interact with the hypothalamic-pituitary-thyroid axis, a document was developed that provides a standardized appro...

  16. Detection of chitinase activity by 2-aminobenzoic acid labeling of chito-oligosaccharides

    NARCIS (Netherlands)

    Ghauharali-van der Vlugt, Karen; Bussink, Anton P.; Groener, Johanna E. M.; Boot, Rolf G.; Aerts, Johannes M. F. G.

    2009-01-01

    Chitinases are hydrolases capable of hydrolyzing the abundant natural polysaccharide chitin. Next to artificial fluorescent substrates, more physiological chito-oligomers are commonly used in chitinase assays. Analysis of chito-oligosaccharides products is generally accomplished by UV detection.

  17. The First Monolithic Silicon Carbide Active Pixel Sensor Array for Solar Blind UV Detection, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This Small Business Innovation Research Phase I project will address the needs of space astronomy, military threat detection, and scientific research for image...

  18. AGILE detection of increasing gamma-ray activity from CTA 102

    Science.gov (United States)

    Lucarelli, F.; Verrecchia, F.; Pittori, C.; Tavani, M.; Vercellone, S.; Colafrancesco, S.; Bulgarelli, A.; Cardillo, M.; Piano, G.; Fioretti, V.; Parmiggiani, N.; Pilia, M.; Donnarumma, I.; Gianotti, F.; Trifoglio, M.; Giuliani, A.; Mereghetti, S.; Caraveo, P.; Perotti, F.; Chen, A.; Argan, A.; Costa, E.; Del Monte, E.; Evangelista, Y.; Feroci, M.; Lazzarotto, F.; Lapshov, I.; Pacciani, L.; Soffitta, P.; Sabatini, S.; Vittorini, V.; Pucella, G.; Rapisarda, M.; Di Cocco, G.; Fuschino, F.; Galli, M.; Labanti, C.; Marisaldi, M.; Pellizzoni, A.; Trois, A.; Barbiellini, G.; Vallazza, E.; Longo, F.; Morselli, A.; Picozza, P.; Prest, M.; Lipari, P.; Zanello, D.; Cattaneo, P. W.; Rappoldi, A.; Ferrari, A.; Paoletti, F.; Antonelli, A.; Giommi, P.; Salotti, L.; Valentini, G.; D'Amico, F.

    2017-12-01

    AGILE is detecting increasing gamma-ray emission above 100 MeV from a source positionally consistent with the FSRQ CTA 102. Integrating from 2017-12-07 06:00 UT to 2017-12-09 06:00 UT, a preliminary maximum likelihood analysis yields a detection above 6 sigma and a flux F(E > 100 MeV)=(3.6 +/- 0.9) x 10^-6 ph cm^-2 s^-1.

  19. Multi-Parameter Observation and Detection of Pre-Earthquake Signals in Seismically Active Areas

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Parrot, M.; Liu, J. Y.; Hattori, K.; Kafatos, M.; Taylor, P.

    2012-01-01

    The recent large earthquakes (M9.0 Tohoku, 03/2011; M7.0 Haiti, 01/2010; M6.7 L Aquila, 04/2008; and M7.9 Wenchuan 05/2008) have renewed interest in pre-anomalous seismic signals associated with them. Recent workshops (DEMETER 2006, 2011 and VESTO 2009 ) have shown that there were precursory atmospheric /ionospheric signals observed in space prior to these events. Our initial results indicate that no single pre-earthquake observation (seismic, magnetic field, electric field, thermal infrared [TIR], or GPS/TEC) can provide a consistent and successful global scale early warning. This is most likely due to complexity and chaotic nature of earthquakes and the limitation in existing ground (temporal/spatial) and global satellite observations. In this study we analyze preseismic temporal and spatial variations (gas/radon counting rate, atmospheric temperature and humidity change, long-wave radiation transitions and ionospheric electron density/plasma variations) which we propose occur before the onset of major earthquakes:. We propose an Integrated Space -- Terrestrial Framework (ISTF), as a different approach for revealing pre-earthquake phenomena in seismically active areas. ISTF is a sensor web of a coordinated observation infrastructure employing multiple sensors that are distributed on one or more platforms; data from satellite sensors (Terra, Aqua, POES, DEMETER and others) and ground observations, e.g., Global Positioning System, Total Electron Content (GPS/TEC). As a theoretical guide we use the Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model to explain the generation of multiple earthquake precursors. Using our methodology, we evaluated retrospectively the signals preceding the most devastated earthquakes during 2005-2011. We observed a correlation between both atmospheric and ionospheric anomalies preceding most of these earthquakes. The second phase of our validation include systematic retrospective analysis for more than 100 major earthquakes (M>5

  20. Investigations on therapeutic glucocerebrosidases through paired detection with fluorescent activity-based probes.

    Directory of Open Access Journals (Sweden)

    Wouter W Kallemeijn

    Full Text Available Deficiency of glucocerebrosidase (GBA causes Gaucher disease (GD. In the common non-neuronopathic GD type I variant, glucosylceramide accumulates primarily in the lysosomes of visceral macrophages. Supplementing storage cells with lacking enzyme is accomplished via chronic intravenous administration of recombinant GBA containing mannose-terminated N-linked glycans, mediating the selective uptake by macrophages expressing mannose-binding lectin(s. Two recombinant GBA preparations with distinct N-linked glycans are registered in Europe for treatment of type I GD: imiglucerase (Genzyme, contains predominantly Man(3 glycans, and velaglucerase (Shire PLC Man(9 glycans. Activity-based probes (ABPs enable fluorescent labeling of recombinant GBA preparations through their covalent attachment to the catalytic nucleophile E340 of GBA. We comparatively studied binding and uptake of ABP-labeled imiglucerase and velaglucerase in isolated dendritic cells, cultured human macrophages and living mice, through simultaneous detection of different GBAs by paired measurements. Uptake of ABP-labeled rGBAs by dendritic cells was comparable, as well as the bio-distribution following equimolar intravenous administration to mice. ABP-labeled rGBAs were recovered largely in liver, white-blood cells, bone marrow and spleen. Lungs, brain and skin, affected tissues in severe GD types II and III, were only poorly supplemented. Small, but significant differences were noted in binding and uptake of rGBAs in cultured human macrophages, in the absence and presence of mannan. Mannan-competed binding and uptake were largest for velaglucerase, when determined with single enzymes or as equimolar mixtures of both enzymes. Vice versa, imiglucerase showed more prominent binding and uptake not competed by mannan. Uptake of recombinant GBAs by cultured macrophages seems to involve multiple receptors, including several mannose-binding lectins. Differences among cells from different donors

  1. Is commercially available point finder accurate and reliable in detecting active auricular acupuncture points?

    Science.gov (United States)

    Wang, Shu-Ming; Maranets, Inna; Lin, Eric C; DeZinno, Peggy

    2012-09-01

    This study was done to determine the specificity and sensitivity of a commercial Pointer Plus (Point finder) in detecting a region of low skin resistance on the ear. This was a prospective blinded study. The study was done at the Yale New Haven Hospital, New Haven, CT. The subjects were men and women who work at Yale New Haven Hospital. There were no interventions. Correlations were made between self-reported musculoskeletal pain and the detection of low skin resistance on the ear. The positive predictive value for Pointer Plus detecting low skin resistance correlating to the neck region of French auricular map is 0.76 (76%). The positive predictive value for Pointer Plus to detect low skin resistance area correlating to the low back region of French auricular map is 0.25. The positive predictive value for Pointer Plus in detecting any low in skin resistance on the external auricles in patients who complained of more than two musculoskeletal pains is 0.29. The specificity and sensitivity of a commercial Pointer Plus (point finder) in detecting a region of low skin resistance on the ear being unreliable, depending on the correlating area based on a published auricular map. Additional assessments are needed to support the clinical practice.

  2. Body Parts Features-Based Pedestrian Detection for Active Pedestrian Protection System

    Directory of Open Access Journals (Sweden)

    Lie Guo

    2016-04-01

    Full Text Available A novel pedestrian detection system based on vision in urban traffic situations is presented to help the driver perceive the pedestrian ahead of the vehicle. To enhance the accuracy and to decrease the time spent on pedestrian detection in such complicated situations, the pedestrian is detected by dividing their body into several parts according to their corresponding features in the image. The candidate pedestrian leg is segmented based on the gentle AdaBoost algorithm by training the optimized histogram of gradient features. The candidate pedestrian head is located by matching the pedestrian head and shoulder model above the region of the candidate leg. Then the candidate leg, head and shoulder are combined by parts constraint and threshold adjustment to verify the existence of the pedestrian. Finally, the experiments in real urban traffic circumstances were conducted. The results show that the proposed pedestrian detection method can achieve pedestrian detection rate of 92.1% with the average detection time of 0.2257 s.

  3. Seeing diabetes: visual detection of glucose based on the intrinsic peroxidase-like activity of MoS2 nanosheets

    Science.gov (United States)

    Lin, Tianran; Zhong, Liangshuang; Guo, Liangqia; Fu, Fengfu; Chen, Guonan

    2014-09-01

    Molybdenum disulfide (MoS2) has attracted increasing research interest recently due to its unique physical, optical and electrical properties, correlated with its 2D ultrathin atomic-layered structure. Until now, however, great efforts have focused on its applications such as lithium ion batteries, transistors, and hydrogen evolution reactions. Herein, for the first time, MoS2 nanosheets are discovered to possess an intrinsic peroxidase-like activity and can catalytically oxidize 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. The catalytic activity follows the typical Michaelis-Menten kinetics and is dependent on temperature, pH, H2O2 concentration, and reaction time. Based on this finding, a highly sensitive and selective colorimetric method for H2O2 and glucose detection is developed and applied to detect glucose in serum samples. Moreover, a simple, inexpensive, instrument-free and portable test kit for the visual detection of glucose in normal and diabetic serum samples is constructed by utilizing agarose hydrogel as a visual detection platform.Molybdenum disulfide (MoS2) has attracted increasing research interest recently due to its unique physical, optical and electrical properties, correlated with its 2D ultrathin atomic-layered structure. Until now, however, great efforts have focused on its applications such as lithium ion batteries, transistors, and hydrogen evolution reactions. Herein, for the first time, MoS2 nanosheets are discovered to possess an intrinsic peroxidase-like activity and can catalytically oxidize 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. The catalytic activity follows the typical Michaelis-Menten kinetics and is dependent on temperature, pH, H2O2 concentration, and reaction time. Based on this finding, a highly sensitive and selective colorimetric method for H2O2 and glucose detection is developed and applied to detect glucose in serum samples. Moreover, a simple, inexpensive

  4. Temporal anomaly detection: an artificial immune approach based on T cell activation, clonal size regulation and homeostasis.

    Science.gov (United States)

    Antunes, Mário J; Correia, Manuel E

    2010-01-01

    This paper presents an artificial immune system (AIS) based on Grossman's tunable activation threshold (TAT) for temporal anomaly detection. We describe the generic AIS framework and the TAT model adopted for simulating T Cells behaviour, emphasizing two novel important features: the temporal dynamic adjustment of T Cells clonal size and its associated homeostasis mechanism. We also present some promising results obtained with artificially generated data sets, aiming to test the appropriateness of using TAT in dynamic changing environments, to distinguish new unseen patterns as part of what should be detected as normal or as anomalous. We conclude by discussing results obtained thus far with artificially generated data sets.

  5. Innovative high pressure gas MEM's based neutron detector for ICF and active SNM detection.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Shawn Bryan; Derzon, Mark Steven; Renzi, Ronald F.; Chandler, Gordon Andrew

    2007-12-01

    An innovative helium3 high pressure gas detection system, made possible by utilizing Sandia's expertise in Micro-electrical Mechanical fluidic systems, is proposed which appears to have many beneficial performance characteristics with regards to making these neutron measurements in the high bremsstrahlung and electrical noise environments found in High Energy Density Physics experiments and especially on the very high noise environment generated on the fast pulsed power experiments performed here at Sandia. This same system may dramatically improve active WMD and contraband detection as well when employed with ultrafast (10-50 ns) pulsed neutron sources.

  6. Pulsed-laser-activated impulse response encoder: Sensitive detection of surface elastic waves on biomimetic microsized gel spheres

    Science.gov (United States)

    Yasukuni, Ryohei; Fukushima, Ryosuke; Iino, Takanori; Hosokawa, Yoichiroh

    2017-11-01

    A femtosecond-laser-induced impulsive force was applied to microsized calcium alginate (CaAlg) gel spheres as an external force to excite elastic waves. To evaluate elasticity, atomic force microscopy (AFM) was applied to detect vibration propagation. The sphere size dependence of the vibration was well reproduced by finite element method (FEM) simulation for pressure waves and surface acoustic waves. The obtained results indicate that the pulsed-laser-activated impulse response encoder (PLAIRE) enables the sensitive detection of elasticities, not only on inside but also on the surface.

  7. Development of a fibre optic goniometer system to measure lumbar and hip movement to detect activities and their lumbar postures.

    Science.gov (United States)

    Bell, J A; Stigant, M

    2007-01-01

    If sitting postures influence the risk of developing low back pain then it is important that quantification of sedentary work activities and simultaneous measurement of lumbar postural characteristics takes place. The objective of this study was to develop a system for identifying activities and their associated lumbar postures using fibre optic goniometers (FOGs). Five student subjects wore two FOGs attached to the lumbar spine and hip for 8 min while being recorded using a video camera when sitting, standing and walking. Observer Software was used to code the video recording, enabling the sagittal movement characteristics of each FOG to be described for individual activities. Results indicated that each activity produced unique data, and could be independently identified from their motion profiles by three raters (k = 1). The data will be used to develop algorithms to automate the process of activity detection. This system has the potential to measure behaviour in non-clinical settings.

  8. Relationship between task execution time and detectability of activation in fMRI hand-grasp movement task

    International Nuclear Information System (INIS)

    Maruyama, Sumito; Muroi, Kenzo; Iinuma, Kazuhiro

    2011-01-01

    To minimize patient requirement in functional magnetic resonance imaging (fMRI) studies, we investigated the relationship between hand grasp movement task execution time and detectability of activation. Using an fMRI time series consisting of 4 sets of rest and task periods (30 s each) as the basic data, we reduced task execution time (τ) by decreasing the number of sets and removing volume from each cycle. We evaluated detectability of activation with different τ based on the number of activated voxels, V n , in the primary motor area (MOT) and cerebellum (CER) in 11 healthy volunteers. The results showed that V n in the MOT and CER decreased linearly with decreasing τ. In addition, the value of V n was clearly smaller with 2 sets than 3 and 4 sets, which suggested that use of 2 sets was not a suitable means for shortening time. The proposed method is expected to be useful for evaluating the relationship between task execution time and detectability of activation, which may reduce task execution time depending on the clinical purpose and thus minimize patient requirement in fMRI studies. (author)

  9. Effective Peroxidase-Like Activity of Co-Aminoclay [CoAC] and Its Application for Glucose Detection

    Directory of Open Access Journals (Sweden)

    Han Pill Song

    2018-02-01

    Full Text Available In this study, we describe a novel peroxidase-like activity of Co-aminoclay [CoAC] present at pH ~5.0 and its application to fluorescent biosensor for the determination of H2O2 and glucose. It is synthesized with aminoclays (ACs entrapping cationic metals such as Fe, Cu, Al, Co., Ce, Ni, Mn, and Zn to find enzyme mimicking ACs by sol–gel ambient conditions. Through the screening of catalytic activities by the typical colorimetric reaction employing 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic aciddiammonium salt (ABTS as a substrate with or without H2O2, Fe, Cu, and CoACs are found to exhibit peroxidase-like activity, as well as oxidase-like activity was observed from Ce and MnACs. Among them, CoAC shows exceptionally high peroxidase-like activity, presumably due to its ability to induce electron transfer between substrates and H2O2. CoAC is then used to catalyze the oxidation of Amplex® UltraRed (AUR into a fluorescent end product, which enables a sensitive fluorescent detection of H2O2. Moreover, a highly sensitive and selective glucose biosensing strategy is developed, based on enzyme cascade reaction between glucose oxidase (GOx and CoAC. Using this strategy, a highly linear fluorescence enhancement is verified when the concentration of glucose is increased in a wide range from 10 μM to 1 mM with a lower detection limit of 5 μM. The practical diagnostic capability of the assay system is also verified by its use to detect glucose in human blood serum. Based on these results, it is anticipated that CoAC can serve as potent peroxidase mimetics for the detection of clinically important target molecules.

  10. Can we detect, monitor, and characterize volcanic activity using 'off the shelf' webcams and low-light cameras?

    Science.gov (United States)

    Harrild, M.; Webley, P. W.; Dehn, J.

    2015-12-01

    The ability to detect and monitor precursory events, thermal signatures, and ongoing volcanic activity in near-realtime is an invaluable tool. Volcanic hazards often range from low level lava effusion to large explosive eruptions, easily capable of ejecting ash to aircraft cruise altitudes. Using ground based remote sensing to detect and monitor this activity is essential, but the required equipment is often expensive and difficult to maintain, which increases the risk to public safety and the likelihood of financial impact. Our investigation explores the use of 'off the shelf' cameras, ranging from computer webcams to low-light security cameras, to monitor volcanic incandescent activity in near-realtime. These cameras are ideal as they operate in the visible and near-infrared (NIR) portions of the electromagnetic spectrum, are relatively cheap to purchase, consume little power, are easily replaced, and can provide telemetered, near-realtime data. We focus on the early detection of volcanic activity, using automated scripts that capture streaming online webcam imagery and evaluate each image according to pixel brightness, in order to automatically detect and identify increases in potentially hazardous activity. The cameras used here range in price from 0 to 1,000 and the script is written in Python, an open source programming language, to reduce the overall cost to potential users and increase the accessibility of these tools, particularly in developing nations. In addition, by performing laboratory tests to determine the spectral response of these cameras, a direct comparison of collocated low-light and thermal infrared cameras has allowed approximate eruption temperatures to be correlated to pixel brightness. Data collected from several volcanoes; (1) Stromboli, Italy (2) Shiveluch, Russia (3) Fuego, Guatemala (4) Popcatépetl, México, along with campaign data from Stromboli (June, 2013), and laboratory tests are presented here.

  11. Colorimetric Detection of Caspase 3 Activity and Reactive Oxygen Derivatives: Potential Early Indicators of Thermal Stress in Corals

    Directory of Open Access Journals (Sweden)

    Mickael Ros

    2016-01-01

    Full Text Available There is an urgent need to develop and implement rapid assessments of coral health to allow effective adaptive management in response to coastal development and global change. There is now increasing evidence that activation of caspase-dependent apoptosis plays a key role during coral bleaching and subsequent mortality. In this study, a “clinical” approach was used to assess coral health by measuring the activity of caspase 3 using a commercial kit. This method was first applied while inducing thermal bleaching in two coral species, Acropora millepora and Pocillopora damicornis. The latter species was then chosen to undergo further studies combining the detection of oxidative stress-related compounds (catalase activity and glutathione concentrations as well as caspase activity during both stress and recovery phases. Zooxanthellae photosystem II (PSII efficiency and cell density were measured in parallel to assess symbiont health. Our results demonstrate that the increased caspase 3 activity in the coral host could be detected before observing any significant decrease in the photochemical efficiency of PSII in the algal symbionts and/or their expulsion from the host. This study highlights the potential of host caspase 3 and reactive oxygen species scavenging activities as early indicators of stress in individual coral colonies.

  12. Ex vivo measurement of calpain activation in human peripheral blood lymphocytes by detection of immunoreactive products of calpastatin degradation.

    Directory of Open Access Journals (Sweden)

    Jacek M Witkowski

    2008-01-01

    Full Text Available Limited proteolysis of multiple intracellular proteins by endogenous Ca-dependent cysteine proteases--calpains--is an important regulatory mechanism for cell proliferation, apoptosis etc. Its importance for cellular functions is stressed by existence of endogenous calpain inhibitors--calpastatins. The calpain-calpastatin system within living cells is in a fragile balance, which depends on both partners. The interdependence of calpain--a protease--and calpastatin--an endogenous inhibitor and at the same time a substrate for this enzyme makes any assessment of actual activity of this enzyme in the cells very difficult. In this work we made an attempt to estimate and compare the activity of calpain in human peripheral blood lymphocytes by assessing the levels of limited proteolysis of calpastatin in these cells by western blot, while at the same time the levels of calpain protein inside these cells was measured by flow cytometry. Our results indicate that it is possible to compare (semi-quantitatively the activities of calpain in peripheral blood CD4+ and CD19+ lymphocytes from various donors that way. Preliminary results showed that calpain activity is increased in the CD4+ T cells isolated from peripheral blood of rheumatoid arthritis patients as compared to control lymphocytes. Extremely high intrinsic activity of calpain was detected in chronic lymphocytic leukemia (CD19+ cells. All this confirms the detection of immunoreactive products of calpastatin as a good maker of endogenous calpain activity.

  13. Colorimetric detection of glucose based on ficin with peroxidase-like activity

    Science.gov (United States)

    Pang, Yanjiao; Huang, Zili; Yang, Yufang; Long, Yijuan; Zheng, Huzhi

    2018-01-01

    In this work, we developed a colorimetric biosensing system for glucose detection by coupling the peroxidase-like of ficin and the glucose oxidase (GOx). GOx can catalyze the oxidation of glucose to produce H2O2, then, ficin catalyzes the oxidation of peroxidase substrate 3,3‧,5,5‧-tetramethylbenzidine (TMB) by H2O2 to produce a blue color reaction. The present sensing system showed a linear response toward glucose detection over range of 2.0-100 μM with a detection limit of 0.5 μM. This system is simple, low cost, highly sensitive and selective for glucose detection, and was also applied to measuring glucose in human serum. Furthermore, in order to expand the application of ficin in biological sensing, we immobilized ficin onto the SiO2@Fe3O4 NPs, which exhibited the merits of recycling as well as allowing the repeated detection of glucose. Thus it may provide great potential applications in biomedicine, biotechnology and environmental chemistry.

  14. Active and passive faults detection by using the PageRank algorithm

    Science.gov (United States)

    Darooneh, Amir H.; Lotfi, Nastaran

    2014-08-01

    Here we try to find active and passive places for earthquakes in the geographical region of Iran. The approach of Abe and Suzuki is adopted for modeling the seismic history of Iran by a complex directed network. By using the PageRank algorithm, we assign to any places in the region an activity index. Then, we determine the most active and passive places.

  15. A program for the a priori evaluation of detection limits in instrumental neutron activation analysis using a SLOWPOKE II reactor

    International Nuclear Information System (INIS)

    Galinier, J.L.; Zikovsky, L.

    1982-01-01

    A program that permits the a priori calculation of detection limits in monoelemental matrices, adapted to instrumental neutron activation analysis using a SLOWPOKE II reactor, is described. A simplified model of the gamma spectra is proposed. Products of (n,p) and (n,α) reactions induced by the fast components of the neutron flux that accompanies the thermal flux at the level of internal irradiation sites in the reactor have been included in the list of interfering radionuclides. The program calculates in a systematic way the detection limits of 66 elements in an equal number of matrices using 153 intermediary radionuclides. Experimental checks carried out with silicon (for short lifetimes) and aluminum and magnesium (for intermediate lifetimes) show satisfactory agreement with the calculations. These results show in particular the importance of the contribution of the (n,p) and (n,α) reactions in the a priori evaluation of detection limits with a SLOWPOKE type reactor [fr

  16. Detection of daily activities and sports with wearable sensors in controlled and uncontrolled conditions.

    Science.gov (United States)

    Ermes, M; Pärkka, J; Mantyjarvi, J; Korhonen, I

    2008-01-01

    Physical activity has a positive impact on people's well-being, and it may also decrease the occurrence of chronic diseases. Activity recognition with wearable sensors can provide feedback to the user about his/her lifestyle regarding physical activity and sports, and thus, promote a more active lifestyle. So far, activity recognition has mostly been studied in supervised laboratory settings. The aim of this study was to examine how well the daily activities and sports performed by the subjects in unsupervised settings can be recognized compared to supervised settings. The activities were recognized by using a hybrid classifier combining a tree structure containing a priori knowledge and artificial neural networks, and also by using three reference classifiers. Activity data were collected for 68 h from 12 subjects, out of which the activity was supervised for 21 h and unsupervised for 47 h. Activities were recognized based on signal features from 3-D accelerometers on hip and wrist and GPS information. The activities included lying down, sitting and standing, walking, running, cycling with an exercise bike, rowing with a rowing machine, playing football, Nordic walking, and cycling with a regular bike. The total accuracy of the activity recognition using both supervised and unsupervised data was 89% that was only 1% unit lower than the accuracy of activity recognition using only supervised data. However, the accuracy decreased by 17% unit when only supervised data were used for training and only unsupervised data for validation, which emphasizes the need for out-of-laboratory data in the development of activity-recognition systems. The results support a vision of recognizing a wider spectrum, and more complex activities in real life settings.

  17. Detection of prion seeding activity in the olfactory mucosa of patients with Fatal Familial Insomnia.

    Science.gov (United States)

    Redaelli, Veronica; Bistaffa, Edoardo; Zanusso, Gianluigi; Salzano, Giulia; Sacchetto, Luca; Rossi, Martina; De Luca, Chiara Maria Giulia; Di Bari, Michele; Portaleone, Sara Maria; Agrimi, Umberto; Legname, Giuseppe; Roiter, Ignazio; Forloni, Gianluigi; Tagliavini, Fabrizio; Moda, Fabio

    2017-04-07

    Fatal Familial Insomnia (FFI) is a genetic prion disease caused by a point mutation in the prion protein gene (PRNP) characterized by prominent thalamic atrophy, diffuse astrogliosis and moderate deposition of PrP Sc in the brain. Here, for the first time, we demonstrate that the olfactory mucosa (OM) of patients with FFI contains trace amount of PrP Sc detectable by PMCA and RT-QuIC. Quantitative PMCA analysis estimated a PrP Sc concentration of about 1 × 10 -14  g/ml. In contrast, PrP Sc was not detected in OM samples from healthy controls and patients affected by other neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease and frontotemporal dementia. These results indicate that the detection limit of these assays is in the order of a single PrP Sc oligomer/molecule with a specificity of 100%.

  18. Quantitative Detection of Active Vibrios Associated with White Plague Disease in Mussismilia braziliensis Corals

    Directory of Open Access Journals (Sweden)

    Luciane A. Chimetto Tonon

    2017-11-01

    Full Text Available Over recent decades several coral diseases have been reported as a significant threat to coral reef ecosystems causing the decline of corals cover and diversity around the world. The development of techniques that improve the ability to detect and quantify microbial agents involved in coral disease will aid in the elucidation of disease cause, facilitating coral disease detection and diagnosis, identification and pathogen monitoring, pathogen sources, vectors, and reservoirs. The genus Vibrio is known to harbor pathogenic strains to marine organisms. One of the best-characterized coral pathogens is Vibrio coralliilyticus, an aetilogic agent of White Plague Disease (WPD. We used Mussismilia coral tissue (healthy and diseased specimens to develop a rapid reproducible detection system for vibrios based on RT-QPCR and SYBR chemistry. We were able to detect total vibrios in expressed RNA targeting the 16S rRNA gene at 5.23 × 106 copies/μg RNA and V. coralliilyticus targeting the pyrH gene at 5.10 × 103 copies/μg RNA in coral tissue. Detection of V. coralliilyticus in diseased and in healthy samples suggests that WPD in the Abrolhos Bank may be caused by a consortium of microorganism and not only a single pathogen. We developed a more practical and economic system compared with probe uses for the real-time detection and quantification of vibrios from coral tissues by using the 16S rRNA and pyrH gene. This qPCR assay is a reliable tool for the monitoring of coral pathogens, and can be useful to prevent, control, or reduce impacts in this ecosystem.

  19. Continuous Active Sonar for Undersea Vehicles Final Report: Input of Factor Graphs into the Detection, Classification, and Localization Chain and Continuous Active SONAR in Undersea Vehicles

    Science.gov (United States)

    2015-12-31

    An example of an acoustic transceiver that could be used for underwater acoustic communication is the WHO! Micro- Modem. It can operate at 10 kHz...Research Laboratory NUMBER The Pennsylvania State University P. 0 . Box 30 State College, PA 16804-0030 9. SPONSORING I MONITORING AGENCY NAME(S...the areas of continuous active sonar (CAS) and unmanned underwater vehicle signal processing. Closed-form factor graph formulations for detection

  20. Transcranial magnetic stimulation of right inferior parietal cortex causally influences prefrontal activation for visual detection

    DEFF Research Database (Denmark)

    Leitao, Joana; Thielscher, Axel; Lee, Hweeling

    2017-01-01

    -parietal areas integrating the evidence into a decision variable that is compared to a decisional threshold. This concurrent transcranial magnetic stimulation (TMS)-fMRI study applied 10 Hz bursts of four TMS (or Sham) pulses to the intraparietal sulcus (IPS) to investigate the causal influence of IPS...... on the neural systems involved in perceptual decision-making. Participants had to detect visual signals at threshold intensity that were presented in their left lower visual field on 50% of the trials. Critically, we adjusted the signal strength such that participants failed to detect the visual stimulus...

  1. Accelerating the peroxidase-like activity of gold nanoclusters at neutral pH for colorimetric detection of heparin and heparinase activity.

    Science.gov (United States)

    Hu, Lianzhe; Liao, Hong; Feng, Lingyan; Wang, Min; Fu, Wensheng

    2018-04-26

    The peroxidase-like catalytic activity of gold nanoclusters (NCs) is quite low around physiological pH, which greatly limits their biological applications. Herein, we found heparin can greatly accelerate the peroxidase-like activity of Au-NCs at neutral pH. The catalytic activity of Au-NCs toward the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) oxidation by H2O2 was 25-fold increased in the presence of heparin at pH 7. The addition of heparin not only accelerated the initial catalytic rate of Au-NCs, but also prevented the Au-NCs from catalyst deactivation. This allows the sensitive colorimetric detection of heparin at neutral pH. In the presence of heparinase, heparin was hydrolyzed into small fragments, weakening the enhancement effect of catalytic activity. Based on this phenomenon, the sensitive colorimetric determination of heparinase in biological samples was also developed.

  2. Restriction in the repertoire of detectable autoantibodies in polyclonal B cell activations and the mimicry of autoantigens by idiotopes

    Directory of Open Access Journals (Sweden)

    L. C. Pontes de Carvalho

    1987-01-01

    Full Text Available Despite the existence of erythrocyte-autoreactive B cells in normal animals, erythrocyte-autoantibodies could not be detected during polyclonal B-cell activation (PBA both in patients with visceral leishmaniasis and in bacterial lipopolysacharide (LPS - injected mice. The failure to detect these autoantibodies in mice with PBA di not seem to be due to suppressor-cell activity, since (1 transfer of spleen cells from LPS-treated mice to naive recipients did not affect the erythrocyte-autoantibody response elicited by subsequent injections of rat erythrocytes and (2 low doses of X-radiation did no lead to erythrocyte-autoantibody detection in LPS-treated mice. The possibility that the detection of erytrocyte-autoantibodies could be affected by autoantibodies with idiotopes mimicring erythrocyte epitopes, the synthesis of which would also be triggerred in PBA, is discussed. Indirect evidence for the existence in normal animal of an expanded lymphocyte population with DNP-binding. Ia-mimicring antigen receptors is presented.

  3. A Preliminary Study on Detecting Fake Gold Bars Using Prompt Gamma Activation Analysis: Simulation of Neutron Transmission in Gold Bar

    International Nuclear Information System (INIS)

    Lee, K. M.; Sun, G. M.

    2016-01-01

    The purpose of this study is to develop fake gold bar detecting method by using Prompt-gamma activation analysis (PGAA) facility at the Korea Atomic Energy Research Institute (KAERI). PGAA is an established nuclear analytical technique for non-destructive determination of elemental and isotopic compositions. For a preliminary study on detecting fake gold bar, Monte Carlo simulation of neutron transmission in gold bar was conducted and the possibility for detecting fake gold bar was confirmed. Under the gold bullion standard, it guaranteed the government would redeem any amount of currency for its value in gold. After the gold bullion standard ended, gold bars have been the target for investment as ever. But it is well known that fake gold bar exist in the gold market. This cannot be identified easily without performing a testing as it has the same appearance as the pure gold bar. In order to avoid the trading of fake gold bar in the market, they should be monitored thoroughly. Although the transmissivity of cold neutrons are low comparing that of thermal neutrons, the slower neutrons are more apt to be absorbed in a target, and can increase the prompt gamma emission rate. Also the flux of both thermal and cold neutron beam is high enough to activate thick target. If the neutron beam is irradiated on the front and the reverse side of gold bar, all insides of it can be detected

  4. Fast joint detection-estimation of evoked brain activity in event-related FMRI using a variational approach

    Science.gov (United States)

    Chaari, Lotfi; Vincent, Thomas; Forbes, Florence; Dojat, Michel; Ciuciu, Philippe

    2013-01-01

    In standard within-subject analyses of event-related fMRI data, two steps are usually performed separately: detection of brain activity and estimation of the hemodynamic response. Because these two steps are inherently linked, we adopt the so-called region-based Joint Detection-Estimation (JDE) framework that addresses this joint issue using a multivariate inference for detection and estimation. JDE is built by making use of a regional bilinear generative model of the BOLD response and constraining the parameter estimation by physiological priors using temporal and spatial information in a Markovian model. In contrast to previous works that use Markov Chain Monte Carlo (MCMC) techniques to sample the resulting intractable posterior distribution, we recast the JDE into a missing data framework and derive a Variational Expectation-Maximization (VEM) algorithm for its inference. A variational approximation is used to approximate the Markovian model in the unsupervised spatially adaptive JDE inference, which allows automatic fine-tuning of spatial regularization parameters. It provides a new algorithm that exhibits interesting properties in terms of estimation error and computational cost compared to the previously used MCMC-based approach. Experiments on artificial and real data show that VEM-JDE is robust to model mis-specification and provides computational gain while maintaining good performance in terms of activation detection and hemodynamic shape recovery. PMID:23096056

  5. Disposable lateral flow-through strip for smartphone-camera to quantitatively detect alkaline phosphatase activity in milk.

    Science.gov (United States)

    Yu, Ling; Shi, ZhuanZhuan; Fang, Can; Zhang, YuanYuan; Liu, YingShuai; Li, ChangMing

    2015-07-15

    A disposable lateral flow-through strip was developed for smartphone to fast one-step quantitatively detect alkaline phosphatase (ALP) activity in raw milk. The strip comprises two functional components, a conjugation pad loaded with phosphotyrosine-coated gold nanoparticles (AuNPs@Cys-Try-p) and a testing line coated with anti-phosphotryosine antibody (anti-Tyr-p mAb). The dephosphorylation activity of ALP at the testing zone can be quantitatively assayed by monitoring the accumulated AuNPs-induced color changes by smartphone camera, thus providing a highly convenient portable detection method. A trace amount of ALP as low as 0.1UL(-1) with a linear dynamic range of 0.1-150UL(-1) (R(2)=0.999) in pasteurized milk and raw milk can be one-step detected by the developed flow-through strip within 10min, demonstrating the potential of smartphone-based portable sensing device for pathogen detection. This bio-hazards free lateral flow-through testing strip can be also used to fabricate rapid, sensitive and inexpensive enzyme or immunosensors for broad portable clinic diagnosis and food contamination analysis, particularly in point-of-care and daily food quality inspection. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Trace detection of herbicides by SERS technique, using SERS-active substrates fabricated from different silver nanostructures deposited on silicon

    International Nuclear Information System (INIS)

    Dao, Tran Cao; Luong, Truc Quynh Ngan; Nguyen, Ngoc Hai; Kieu, Ngoc Minh; Luong, Thi Thuy; Cao, Tuan Anh; Le, Van Vu

    2015-01-01

    In this report we present the initial results of the use of different silver nanostructures deposited on silicon for trace detection of paraquat (a commonly used herbicide) using the surface-enhanced Raman scattering (SERS) effect. More specifically, the SERS-active substrates were fabricated from silver nanoparticles (AgNPs) deposited onto the flat surface of a silicon wafer (AgNPs@Si substrate), as well as on the surface of an obliquely aligned silicon nanowire (SiNW) array (AgNPs@SiNWs substrate), and from silver nanodendrites (AgNDs) deposited onto the flat surface of a silicon wafer (AgNDs@Si substrate). Results showed that with the change of the structure of the SERS-active substrate, higher levels of SERS enhancement have been achieved. Specifically, with the fabricated AgNDs@Si substrate, paraquat concentration as low as 1 ppm can be detected. (paper)

  7. Membrane Active Small Molecules Show Selective Broad Spectrum Antibacterial Activity with No Detectable Resistance and Eradicate Biofilms.

    Science.gov (United States)

    Hoque, Jiaul; Konai, Mohini M; Gonuguntla, Spandhana; Manjunath, Goutham B; Samaddar, Sandip; Yarlagadda, Venkateswarlu; Haldar, Jayanta

    2015-07-23

    Treating bacterial biofilms with conventional antibiotics is limited due to ineffectiveness of the drugs and higher propensity to develop bacterial resistance. Development of new classes of antibacterial therapeutics with alternative mechanisms of action has become imperative. Herein, we report the design, synthesis, and biological evaluations of novel membrane-active small molecules featuring two positive charges, four nonpeptidic amide groups, and variable hydrophobic/hydrophilic (amphiphilic) character. The biocides synthesized via a facile methodology not only displayed good antibacterial activity against wild-type bacteria but also showed high activity against various drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE), and β-lactam-resistant Klebsiella pneumoniae. Further, these biocides not only inhibited the formation of biofilms but also disrupted the established S. aureus and E. coli biofilms. The membrane-active biocides hindered the propensity to develop bacterial resistance. Moreover, the biocides showed negligible toxicity against mammalian cells and thus bear potential to be used as therapeutic agents.

  8. Trimpi occurrence and geomagnetic activity: Analysis of events detected at Comandante Ferraz Brazilian Antarctic Station (L=2.25)

    OpenAIRE

    Fernandez, JH; Piazza, LR; Kaufmann, P

    2003-01-01

    [1] We present an analysis of the occurrence of Trimpi events observed at Comandante Ferraz Brazilian Antarctic Station (EACF), at L = 2.25, as observed by the amplitude of very low frequency (VLF) signals transmitted from Hawaii (NPM 21.4 kHz) from April 1996 to August 1999. The event parameters ( total duration, amplitude variation, time incidence, and type ( negative or positive)) were analyzed for 4394 events detected in the first year ( solar minimum and relatively low Trimpi activity). ...

  9. Silver-Stained Fibrin Zymography: Separation of Proteases and Activity Detection Using a Single Substrate-Containing Gel.

    Science.gov (United States)

    Park, Chang-Su; Kang, Dae-Ook; Choi, Nack-Shick

    2017-01-01

    Silver-stained fibrin zymography for separation of protease bands and activity detection using a single substrate gel was designed. The method takes advantage of the nano-scale sensitivity of both zymography and silver staining. After sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) in a gel containing fibrin (protease substrate), the gel was incubated in enzyme reaction buffer and the zymogram gel was silver-stained. Bands with protease activity were stained with silver in clear areas where the protein substrate had been degraded. The molecular sizes of proteases were accurately determined.

  10. Passive and active correlation techniques for the detection of nuclear materials

    International Nuclear Information System (INIS)

    Deyglun, Clement; Carasco, Cedric; Perot, Bertrand; Eleon, Cyrille; Sannie, Guillaume; Boudergui, Karim; Corre, Gwenole; Konzdrasovs, Vladimir; Pras, Philippe

    2013-06-01

    In the frame of the French trans-governmental R and D program against CBRN-E threats, CEA (French Alternative Energies and Atomic Energy Commission) is studying the detection of Special Nuclear Materials (SNM) by neutron interrogation with the Associated Particle Technique (APT). Coincidences including at least 3 fission neutrons or gamma rays induced by tagged neutrons are used to detect and distinguish SNM from benign materials in which lower multiplicity events of 1 or 2 particles are produced by (n, 2n) or (n, n'γ) reactions. Coincidence are detected by fast plastic scintillators and correlated with tagged neutrons to improve the signal-to-noise ratio. Dedicated data acquisition electronics (DAQ) has been developed with independent FPGA cards associated to each detector, so that the acquisition window can be opened by any of the plastic scintillators. DAQ tests in passive mode are presented, in which acquisition is triggered by the sum signal of all detectors. The system time and energy calibration and resolution are reported, as well as the qualification of numerical simulations thanks to experimental data acquired with simple setups using a 252 Cf source. Numerical studies for the design and performance of cargo container inspection are also performed with the MCNP-PoliMi computer code and the ROOT data analysis package. SNM detection in iron cargo is quite straightforward but in organic matrix, data processing will need to combine more information to evidence SNM. (authors)

  11. The sensitivity of tests to detect in vivo platelet activation induced by ...

    African Journals Online (AJOL)

    No influence on the results of the platelet function tests was found. Tile only test capable of detecting limited injury to the endothelium was the measurement of plasma PF4: The mean platelet life-span (MPLS) shortened, mean platelet density decreased, the circulating platelet aggregate ratio decreased, and plasma levels ...

  12. Detection of Abnormal Muscle Activations during Walking Following Spinal Cord Injury (SCI)

    Science.gov (United States)

    Wang, Ping; Low, K. H.; McGregor, Alison H.; Tow, Adela

    2013-01-01

    In order to identify optimal rehabilitation strategies for spinal cord injury (SCI) participants, assessment of impaired walking is required to detect, monitor and quantify movement disorders. In the proposed assessment, ten healthy and seven SCI participants were recruited to perform an over-ground walking test at slow walking speeds. SCI…

  13. Chromobacterium sp. from the tropics: detection and diversity of phytase activity

    Directory of Open Access Journals (Sweden)

    Patrícia S Costa

    2011-03-01

    Full Text Available Phytases are a group of enzymes that catalyze phytic acid hydrolysis with release of phosphorus (P. The ability of Chromobacterium sp. to produce phytase was detected in 115 out of 118 candidate bacteria isolated from different Brazilian biomas. This is the first report revealing the genus Chromobacterium as phytase producer.

  14. Swift detects increased activity of the neutron star transient SAX J1750.8-2900

    NARCIS (Netherlands)

    Linares, M.; Degenaar, N.; Wijnands, R.; Altamirano, D.

    2008-01-01

    After our report on the flux decay of the neutron star transient SAX J1750.8-2900 (ATel #1662) we have continued monitoring the source with Swift-XRT in order to study its transition to quiescence. In these observations (performed between August 14th. and October 8th.) we detect the source at

  15. Earlier activity from XTE J1739-302/IGR J17391-3021 detected by INTEGRAL

    DEFF Research Database (Denmark)

    Chenevez, Jérôme; Beckmann, V.; Kuulkers, E.

    2008-01-01

    The recently reported outburst from the supergiant fast X-ray transient XTE J1739-302/IGR J17391-3021 (ATEL #1466) began already about five hours earlier than the Swift/BAT trigger on 2008-04-08. The INTEGRAL/JEM-X monitor detected a flare starting at 16:18 (UTC) on the same day during recent Gal...

  16. A sensitive two-photon probe to selectively detect monoamine oxidase B activity in Parkinson’s disease models

    Science.gov (United States)

    Li, Lin; Zhang, Cheng-Wu; Chen, Grace Y. J.; Zhu, Biwei; Chai, Chou; Xu, Qing-Hua; Tan, Eng-King; Zhu, Qing; Lim, Kah-Leong; Yao, Shao Q.

    2014-02-01

    The unusually high MAO-B activity consistently observed in Parkinson’s disease (PD) patients has been proposed as a biomarker; however, this has not been realized due to the lack of probes suitable for MAO-B-specific detection in live cells/tissues. Here we report the first two-photon, small molecule fluorogenic probe (U1) that enables highly sensitive/specific and real-time imaging of endogenous MAO-B activities across biological samples. We also used U1 to confirm the reported inverse relationship between parkin and MAO-B in PD models. With no apparent toxicity, U1 may be used to monitor MAO-B activities in small animals during disease development. In clinical samples, we find elevated MAO-B activities only in B lymphocytes (not in fibroblasts), hinting that MAO-B activity in peripheral blood cells might be an accessible biomarker for rapid detection of PD. Our results provide important starting points for using small molecule imaging techniques to explore MAO-B at the organism level.

  17. fMRI study of graduated emotional charge for detection of covert activity using passive listening to narratives.

    Science.gov (United States)

    Sontheimer, Anna; Vassal, François; Jean, Betty; Feschet, Fabien; Lubrano, Vincent; Lemaire, Jean-Jacques

    2017-05-04

    Detection of awareness in patients with consciousness disorders is a challenge that can be facilitated by functional neuroimaging. We elaborated a functional magnetic resonance imaging (fMRI) protocol to detect covert activity in altered states of consciousness. We hypothesized that passive listening to narratives with graduated emotional charge triggers graduated cerebral activations. The fMRI protocol was designed in healthy subjects for further clinical applications. The emotional charge was graduated using voice familiarity and long-term declarative memory content: low emotional charge, unknown person telling general semantic memory; mean emotional charge, relative telling the same narratives; high emotional charge, same relative telling autobiographical memory. Autobiographical memory was subdivided into semantic autobiographical memory and episodic autobiographical memory. The protocol proved efficient at triggering graduated cerebral activations: low emotional charge, superior temporal gyri and sulci; mean emotional charge, same as low emotional charge plus bilateral premotor cortices and left inferior frontal gyrus; high emotional charge, cingulate, temporal, frontal, prefrontal and angular areas, thalamus and cerebellum. Semantic autobiographical memory revealed larger activations than episodic autobiographical memory. Independent ROI analysis confirmed the preponderant contribution of narratives with autobiographical memory content in triggering cerebral activation, not only in autobiographical memory-sensitive areas, but also in voice-sensitive, language-sensitive and semantic memory-sensitive areas. Copyright © 2017. Published by Elsevier Ltd.

  18. Detection of endocrine active substances in the aquatic environment in southern Taiwan using bioassays and LC-MS/MS.

    Science.gov (United States)

    Chen, Kuang-Yu; Chou, Pei-Hsin

    2016-06-01

    Endocrine active substances, including naturally occurring hormones and various synthetic chemicals have received much concern owing to their endocrine disrupting potencies. It is essential to monitor their environmental occurrence since these compounds may pose potential threats to biota and human health. In this study, yeast-based reporter assays were carried out to investigate the presence of (anti-)androgenic, (anti-)estrogenic, and (anti-)thyroid compounds in the aquatic environment in southern Taiwan. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was also used to measure the environmental concentrations of selected endocrine active substances for assessing potential ecological risks and characterizing contributions to the endocrine disrupting activities. Bioassay results showed that anti-androgenic (ND-7489 μg L(-1) flutamide equivalent), estrogenic (ND-347 ng L(-1) 17β-estradiol equivalent), and anti-thyroid activities were detected in the dissolved and particulate phases of river water samples, while anti-estrogenic activities (ND-10 μg L(-1) 4-hydroxytamoxifen equivalent) were less often found. LC-MS/MS analysis revealed that anti-androgenic and estrogenic contaminants, such as bisphenol A, triclosan, and estrone were frequently detected in Taiwanese rivers. In addition, their risk quotient values were often higher than 1, suggesting that they may pose an ecological risk to the aquatic biota. Further identification of unknown anti-androgenic and estrogenic contaminants in Taiwanese rivers may be necessary to protect Taiwan's aquatic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. 3D Fractals as SERS Active Platforms: Preparation and Evaluation for Gas Phase Detection of G-Nerve Agents

    Directory of Open Access Journals (Sweden)

    Marta Lafuente

    2018-01-01

    Full Text Available One of the main limitations of the technique surface-enhanced Raman scattering (SERS for chemical detection relies on the homogeneity, reproducibility and reusability of the substrates. In this work, SERS active platforms based on 3D-fractal microstructures is developed by combining corner lithography and anisotropic wet etching of silicon, to extend the SERS-active area into 3D, with electrostatically driven Au@citrate nanoparticles (NPs assembly, to ensure homogeneous coating of SERS active NPs over the entire microstructured platforms. Strong SERS intensities are achieved using 3D-fractal structures compared to 2D-planar structures; leading to SERS enhancement factors for R6G superior than those merely predicted by the enlarged area effect. The SERS performance of Au monolayer-over-mirror configuration is demonstrated for the label-free real-time gas phase detection of 1.2 ppmV of dimethyl methylphosphonate (DMMP, a common surrogate of G-nerve agents. Thanks to the hot spot accumulation on the corners and tips of the 3D-fractal microstructures, the main vibrational modes of DMMP are clearly identified underlying the spectral selectivity of the SERS technique. The Raman acquisition conditions for SERS detection in gas phase have to be carefully chosen to avoid photo-thermal effects on the irradiated area.

  20. The effect of housing condition on the performance of two types of activity meters to detect estrus in dairy cows.

    Science.gov (United States)

    Roelofs, J B; Krijnen, C; van Erp-van der Kooij, E

    2017-04-15

    When the daily routine of a cow is disturbed, it may have a detrimental effect on the performance of activity meters to detect estrus. It is possible that during the pasture period, the daily routine of cows is disturbed, adversely affecting the performance of activity meters to detect estrus which does not happen when the cows are housed indoors. The objective of this study was to investigate whether housing conditions (pasture or indoor) affected the performance of activity meters to detect estrus in dairy cows. In this research, two types of activity meters were used, an activity meter attached to the leg and one mounted on the neck. Cows of two different herds were equipped with the Smarttag Leg and the Smarttag Neck (Nedap livestock management, Groenlo, the Netherlands). The study began during the pasture period (September) and ended during the indoor period (January). The pasture period ended at the beginning of November. So, about two months of pasture period and two months of indoor period were studied. Milk samples were collected twice a week during the morning milking and true estrus was determined by milk progesterone concentrations. In total, the dataset consisted of 95 true estrous periods and 1992 true non-estrous days of 56 cows for the pasture period and 138 true estrous periods and 3164 true non-estrous days of 65 cows for the indoor period. Overall, no differences in sensitivity, positive predictive value (PPV) and specificity were found between the pasture and indoor period for both types of sensors. There was also no difference in the performance between leg and neck activity meters. Sensitivity was between 76 and 82%, PPV was between 87 and 92% and specificity was between 99 and 100%. In conclusion, the sensitivity, PPV and specificity did not differ between the pasture and indoor period. This means that, in our study, the performance of both types of activity meters to detect estrus is not affected by housing conditions. Copyright © 2017

  1. STELLAR ACTIVITY AND ITS IMPLICATIONS FOR EXOPLANET DETECTION ON GJ 176

    International Nuclear Information System (INIS)

    Robertson, Paul; Endl, Michael; Cochran, William D.; MacQueen, Phillip J.; Henry, Gregory W.; Williamson, Michael H.

    2015-01-01

    We present an in-depth analysis of stellar activity and its effects on radial velocity (RV) for the M2 dwarf GJ 176 based on spectra taken over 10 yr from the High Resolution Spectrograph on the Hobby-Eberly Telescope. These data are supplemented with spectra from previous observations with the HIRES and HARPS spectrographs, and V- and R-band photometry taken over six years at the Dyer and Fairborn observatories. Previous studies of GJ 176 revealed a super-Earth exoplanet in an 8.8-day orbit. However, the velocities of this star are also known to be contaminated by activity, particularly at the 39-day stellar rotation period. We have examined the magnetic activity of GJ 176 using the sodium I D lines, which have been shown to be a sensitive activity tracer in cool stars. In addition to rotational modulation, we see evidence of a long-term trend in our Na I D index, which may be part of a long-period activity cycle. The sodium index is well correlated with our RVs, and we show that this activity trend drives a corresponding slope in RV. Interestingly, the rotation signal remains in phase in photometry, but not in the spectral activity indicators. We interpret this phenomenon as the result of one or more large spot complexes or active regions which dominate the photometric variability, while the spectral indices are driven by the overall magnetic activity across the stellar surface. In light of these results, we discuss the potential for correcting activity signals in the RVs of M dwarfs

  2. Preparing electrochemical active hierarchically porous carbons for detecting nitrite in drinkable water

    KAUST Repository

    Ding, Baojun

    2016-01-13

    A class of hierarchically porous carbons were prepared by a facile dual-templating approach. The obtained samples were characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, Brunaner-Emmett-Teller measurement and electrochemical work station, respectively. The porous carbons could possess large specific surface area, interconnected pore structures, high conductivity and graphitizing degree. The resulting materials were used to prepare integrated modified electrodes. Based on the experimental results, the as-prepared hierarchically porous graphite (HPG) modified electrode showed the best electroactive performances toward the detection of nitrite with a detection limit of 8.1 × 10-3 mM. This HPG electrode was also repeatable and stable for 6 weeks. Moreover, this electrode was used for the determination of nitrite in drinkable water, and had acceptable recoveries. © The Royal Society of Chemistry 2016.

  3. In situ calibration of position detection in an optical trap for active microrheology in viscous materials.

    Science.gov (United States)

    Staunton, Jack R; Blehm, Ben; Devine, Alexus; Tanner, Kandice

    2017-02-06

    In optical trapping, accurate determination of forces requires calibration of the position sensitivity relating displacements to the detector readout via the V-nm conversion factor (β). Inaccuracies in measured trap stiffness (k) and dependent calculations of forces and material properties occur if β is assumed to be constant in optically heterogeneous materials such as tissue, necessitating calibration at each probe. For solid-like samples in which probes are securely positioned, calibration can be achieved by moving the sample with a nanopositioning stage and stepping the probe through the detection beam. However, this method may be applied to samples only under select circumstances. Here, we introduce a simple method to find β in any material by steering the detection laser beam while the probe is trapped. We demonstrate the approach in the yolk of living Danio rerio (zebrafish) embryos and measure the viscoelastic properties over an order of magnitude of stress-strain amplitude.

  4. Real-time detection of antibiotic activity by measuring nanometer-scale bacterial deformation

    Science.gov (United States)

    Iriya, Rafael; Syal, Karan; Jing, Wenwen; Mo, Manni; Yu, Hui; Haydel, Shelley E.; Wang, Shaopeng; Tao, Nongjian

    2017-12-01

    Diagnosing antibiotic-resistant bacteria currently requires sensitive detection of phenotypic changes associated with antibiotic action on bacteria. Here, we present an optical imaging-based approach to quantify bacterial membrane deformation as a phenotypic feature in real-time with a nanometer scale (˜9 nm) detection limit. Using this approach, we found two types of antibiotic-induced membrane deformations in different bacterial strains: polymyxin B induced relatively uniform spatial deformation of Escherichia coli O157:H7 cells leading to change in cellular volume and ampicillin-induced localized spatial deformation leading to the formation of bulges or protrusions on uropathogenic E. coli CFT073 cells. We anticipate that the approach will contribute to understanding of antibiotic phenotypic effects on bacteria with a potential for applications in rapid antibiotic susceptibility testing.

  5. The effects of sleep deprivation on brain fMRI activation during motion detection and tracking

    OpenAIRE

    Robinson, G.

    2008-01-01

    Sleep deprivation is common and leads to inattention and impaired vigilance. Sleep deprived drivers have an increased road traffic accident rate. Police data suggest that sleep deprivation accounts for up to 23% of all accidents on UK roads. How sleep deprivation leads to impaired driving is uncertain. The skills needed for error free driving are the detection of moving objects, and the ability to track. Work using Functional Magnetic Resonance Imaging (fMRI) has established which brain areas...

  6. A tosyl-activated magnetic bead cellulose as solid support for sensitive protein detection

    Czech Academy of Sciences Publication Activity Database

    Yan, J.; Horák, Daniel; Lenfeld, Jiří; Hammond, M.; Kamali-Moghaddam, M.

    2013-01-01

    Roč. 167, č. 3 (2013), s. 235-240 ISSN 0168-1656 R&D Projects: GA ČR GAP503/10/0664; GA MŠk 7E12054 EU Projects: European Commission(XE) 259796 - DIATOOLS Institutional support: RVO:61389013 Keywords : bead cellulose * magnetic * protein detection Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.884, year: 2013

  7. INTEGRAL confirms the detection of renewed activity from the NS transient H 1658-298

    DEFF Research Database (Denmark)

    Sanchez-Fernandez, C.; Eckert, D.; Bozzo, E.

    2015-01-01

    INTEGRAL observed the Galactic Center Region between (UT) 2015-08-22 05:26 and 18:44. Enhanced X-ray emission was detected by the Joint European Monitor for X-rays (JEM-X) in the 3-10 keV band, (15 mCrab; 9-sigma significance) at the following position: (R.A., Dec) = (255.5284, -29.94175) = (17 0...

  8. Visual detection of Brucella in bovine biological samples using DNA-activated gold nanoparticles.

    Directory of Open Access Journals (Sweden)

    Dheeraj Pal

    Full Text Available Brucellosis is a bacterial disease, which, although affecting cattle primarily, has been associated with human infections, making its detection an important challenge. The existing gold standard diagnosis relies on the culture of bacteria which is a lengthy and costly process, taking up to 45 days. New technologies based on molecular diagnosis have been proposed, either through dip-stick, immunological assays, which have limited specificity, or using nucleic acid tests, which enable to identify the pathogen, but are impractical for use in the field, where most of the reservoir cases are located. Here we demonstrate a new test based on hybridization assays with metal nanoparticles, which, upon detection of a specific pathogen-derived DNA sequence, yield a visual colour change. We characterise the components used in the assay with a range of analytical techniques and show sensitivities down to 1000 cfu/ml for the detection of Brucella. Finally, we demonstrate that the assay works in a range of bovine samples including semen, milk and urine, opening up the potential for its use in the field, in low-resource settings.

  9. C-band Joint Active/Passive Dual Polarization Sea Ice Detection

    Science.gov (United States)

    Keller, M. R.; Gifford, C. M.; Winstead, N. S.; Walton, W. C.; Dietz, J. E.

    2017-12-01

    A technique for synergistically-combining high-resolution SAR returns with like-frequency passive microwave emissions to detect thin (standard deviation to mean) has fewer ambiguities between ice and water than cross sections, but breaking waves still produce ice-like signatures for both polarizations. For the radiometer, the PRIC (polarization ratio ice concentration) identifies areas that are unambiguously water. Applying cumulative statistics to co-located COV levels adaptively determines an ice/water threshold. Outcomes from extensive testing with Sentinel and AMSR-2 data are shown in the results. The detection algorithm was applied to the freeze-up in the Beaufort, Chukchi, Barents, and East Siberian Seas in 2015 and 2016, spanning mid-September to early November of both years. At the end of the melt, 6 GHz PRIC values are 5-10% greater than those reported by radiometric algorithms at 19 and 37 GHz. During freeze-up, COV separates grease ice (concentrations than operational scatterometer or radiometer algorithms, mostly from ice edge and coastal areas. In conclusion, the algorithm presented combines high-resolution SAR returns with passive microwave emissions for automated ice detection at SAR resolutions.

  10. Pattern Extraction Algorithm for NetFlow-Based Botnet Activities Detection

    Directory of Open Access Journals (Sweden)

    Rafał Kozik

    2017-01-01

    Full Text Available As computer and network technologies evolve, the complexity of cybersecurity has dramatically increased. Advanced cyber threats have led to current approaches to cyber-attack detection becoming ineffective. Many currently used computer systems and applications have never been deeply tested from a cybersecurity point of view and are an easy target for cyber criminals. The paradigm of security by design is still more of a wish than a reality, especially in the context of constantly evolving systems. On the other hand, protection technologies have also improved. Recently, Big Data technologies have given network administrators a wide spectrum of tools to combat cyber threats. In this paper, we present an innovative system for network traffic analysis and anomalies detection to utilise these tools. The systems architecture is based on a Big Data processing framework, data mining, and innovative machine learning techniques. So far, the proposed system implements pattern extraction strategies that leverage batch processing methods. As a use case we consider the problem of botnet detection by means of data in the form of NetFlows. Results are promising and show that the proposed system can be a useful tool to improve cybersecurity.

  11. Detection of marine neurotoxins and characterization of the presynaptic activity of iotrochotin from the sponge Iotrochota birotulata

    International Nuclear Information System (INIS)

    Martin, J.V.

    1987-01-01

    In order to detect novel presynaptic neurotoxins, a total of 766 extracts from marine organisms collected during expeditions of the research vessel Alpha Helix around the peninsula of Baja Mexico in 1974 and through the Caribbean in 1978 were tested for activity in a synaptosomal assay for the release of acetylcholine (ACh). To eliminate from consideration sample extracts which lysed the synaptosomal membrane, lactate dehydrogenase (LDH) activity was measured as a cytoplasmic marker. On the basis of the screening studies the extract of the sponge lotrochota birotulata was chosen for more detailed characterization. The active factor, iotrochotin (IOT), was sensitive to thermal inactivation, was partially activated by trypsin treatment and had a molecular weight of 12,000-13,000. The activity of IOT was found to be complete by one minute. The maximal release of radioactivity from synaptosomes preloaded with [ 3 H]choline was found to be dependent on the concentration of IOT irrespective of the time of further incubation. The concentration-response curve of IOT activity showed a sigmoid shape which did not fit the Hill equation. IOT caused release of both ACh and choline. Of the radioactivity released by IOT from synaptosomes preloaded with [ 3 H]choline, 50-60% was [ 3 H]ACh. IOT also released [ 3 H]GABA and [ 3 H]norepinephrine from synaptosomes preincubated with these labeled neurotransmitters. The activity of IOT was only minimally sensitive to reduction in Na + or Ca 2+ levels, and was not sensitive to tetrodotoxin. IOT did not dramatically change the fluorescence of synaptosomes incubated with a depolarization-indicating dye. However, depolarization of synaptosomes with high concentrations of K + was still detectable by this method in the presence of IOT

  12. Preliminary clinical results: an analyzing tool for 2D optical imaging in detection of active inflammation in rheumatoid arthritis

    Science.gov (United States)

    Adi Aizudin Bin Radin Nasirudin, Radin; Meier, Reinhard; Ahari, Carmen; Sievert, Matti; Fiebich, Martin; Rummeny, Ernst J.; No"l, Peter B.

    2011-03-01

    Optical imaging (OI) is a relatively new method in detecting active inflammation of hand joints of patients suffering from rheumatoid arthritis (RA). With the high number of people affected by this disease especially in western countries, the availability of OI as an early diagnostic imaging method is clinically highly relevant. In this paper, we present a newly in-house developed OI analyzing tool and a clinical evaluation study. Our analyzing tool extends the capability of existing OI tools. We include many features in the tool, such as region-based image analysis, hyper perfusion curve analysis, and multi-modality image fusion to aid clinicians in localizing and determining the intensity of inflammation in joints. Additionally, image data management options, such as the full integration of PACS/RIS, are included. In our clinical study we demonstrate how OI facilitates the detection of active inflammation in rheumatoid arthritis. The preliminary clinical results indicate a sensitivity of 43.5%, a specificity of 80.3%, an accuracy of 65.7%, a positive predictive value of 76.6%, and a negative predictive value of 64.9% in relation to clinical results from MRI. The accuracy of inflammation detection serves as evidence to the potential of OI as a useful imaging modality for early detection of active inflammation in patients with rheumatoid arthritis. With our in-house developed tool we extend the usefulness of OI imaging in the clinical arena. Overall, we show that OI is a fast, inexpensive, non-invasive and nonionizing yet highly sensitive and accurate imaging modality.-

  13. Corrosion detection of steel reinforced concrete using combined carbon fiber and fiber Bragg grating active thermal probe

    International Nuclear Information System (INIS)

    Li, Weijie; Ho, Siu Chun Michael; Song, Gangbing

    2016-01-01

    Steel reinforcement corrosion is one of the dominant causes for structural deterioration for reinforced concrete structures. This paper presents a novel corrosion detection technique using an active thermal probe. The technique takes advantage of the fact that corrosion products have poor thermal conductivity, which will impede heat propagation generated from the active thermal probe. At the same time, the active thermal probe records the temperature response. The presence of corrosion products can thus be detected by analyzing the temperature response after the injection of heat at the reinforcement-concrete interface. The feasibility of the proposed technique was firstly analyzed through analytical modeling and finite element simulation. The active thermal probe consisted of carbon fiber strands to generate heat and a fiber optic Bragg grating (FBG) temperature sensor. Carbon fiber strands are used due to their corrosion resistance. Wet-dry cycle accelerated corrosion experiments were performed to study the effect of corrosion products on the temperature response of the reinforced concrete sample. Results suggest a high correlation between corrosion severity and magnitude of the temperature response. The technique has the merits of high accuracy, high efficiency in measurement and excellent embeddability. (paper)

  14. More efficient integrated safeguards by applying a reasonable detection probability for maintaining low presence probability of undetected nuclear proliferating activities

    International Nuclear Information System (INIS)

    Otsuka, Naoto

    2013-01-01

    Highlights: • A theoretical foundation is presented for more efficient Integrated Safeguards (IS). • Probability of undetected nuclear proliferation activities should be maintained low. • For nations under IS, the probability to start proliferation activities is very low. • The fact can decrease the detection probability of IS by dozens of percentage points. • The cost of IS per nation can be cut down by reducing inspection frequencies etc. - Abstract: A theoretical foundation is presented for implementing more efficiently the present International Atomic Energy Agency (IAEA) integrated safeguards (ISs) on the basis of fuzzy evaluation of the probability that the evaluated nation will continue peaceful activities. It is shown that by determining the presence probability of undetected nuclear proliferating activities, nations under IS can be maintained at acceptably low proliferation risk levels even if the detection probability of current IS is decreased by dozens of percentage from the present value. This makes it possible to reduce inspection frequency and the number of collected samples, allowing the IAEA to cut costs per nation. This will contribute to further promotion and application of IS to more nations by the IAEA, and more efficient utilization of IAEA resources from the viewpoint of whole IS framework

  15. A Case for Call Activity Detection for ATM Voice Services in Project Parakeet

    National Research Council Canada - National Science Library

    Blair, W

    1998-01-01

    .... This report seeks to quantify capacity economies which can be achieved through the development of an adaptive approach to voice services on the ATM network by transmitting only active connections...

  16. SERMs and SARMs: Detection of their activities with yeast based bioassays

    NARCIS (Netherlands)

    Bovee, T.F.H.; Thevis, M.; Hamers, A.R.M.; Peijnenburg, A.A.C.M.; Nielen, M.W.F.; Schoonen, W.G.E.J.

    2010-01-01

    Selective estrogen receptor modulators (SERMs) and selective androgen receptor modulators (SARMs) are compounds that activate their cognate receptor in particular target tissues without affecting other organs. Many of these compounds will find their use in therapeutic treatments. However, they also

  17. Chloroform-free permeabilization for improved detection of β-galactosidase activity in Vibrio cholerae.

    Science.gov (United States)

    Toulouse, Charlotte; Häse, Claudia C; Steuber, Julia

    2017-06-01

    LacZ (β-galactosidase) is used to monitor the transcription of genes in reporter strains carrying the lacZ gene under the control of a promotor of interest. This protocol for LacZ activity determinations in Vibrio cholerae following detergent lysis results in 2.5-fold increase of LacZ activities compared to lysis with chloroform. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. DNA Nanoparticles: Detection of Long-Term Transgene Activity in Brain using Bioluminescence Imaging

    Directory of Open Access Journals (Sweden)

    David M. Yurek

    2011-09-01

    Full Text Available In this study, we used bioluminescence imaging (BLI to track long-term transgene activity following the transfection of brain cells using a nonviral gene therapy technique. Formulations of deoxyribonucleic acid (DNA combined with 30-mer lysine polymers (substituted with 10 kDa polyethylene glycol form nanoparticles that transfect brain cells in vivo and produce transgene activity. Here we show that a single intracerebral injection of these DNA nanoparticles (DNPs into the rat cortex, striatum, or substantia nigra results in long-term and persistent luciferase transgene activity over an 8- to 11-week period as evaluated by in vivo BLI analysis, and single injections of DNPs into the mouse striatum showed stable luciferase transgene activity for 1 year. Compacted DNPs produced in vivo signals 7- to 34-fold higher than DNA alone. In contrast, ex vivo BLI analysis, which is subject to less signal quenching from surrounding tissues, demonstrated a DNP to DNA alone ratio of 76- to 280-fold. Moreover, the ex vivo BLI analysis confirmed that signals originated from the targeted brain structures. In summary, BLI permits serial analysis of luciferase transgene activity at multiple brain locations following gene transfer with DNPs. Ex vivo analysis may permit more accurate determination of relative activities of gene transfer vectors.

  19. A Label-Free Microfluidic Biosensor for Activity Detection of Single Microalgae Cells Based on Chlorophyll Fluorescence

    Directory of Open Access Journals (Sweden)

    Junsheng Wang

    2013-11-01

    Full Text Available Detection of living microalgae cells is very important for ballast water treatment and analysis. Chlorophyll fluorescence is an indicator of photosynthetic activity and hence the living status of plant cells. In this paper, we developed a novel microfluidic biosensor system that can quickly and accurately detect the viability of single microalgae cells based on chlorophyll fluorescence. The system is composed of a laser diode as an excitation light source, a photodiode detector, a signal analysis circuit, and a microfluidic chip as a microalgae cell transportation platform. To demonstrate the utility of this system, six different living and dead algae samples (Karenia mikimotoi Hansen, Chlorella vulgaris, Nitzschia closterium, Platymonas subcordiformis, Pyramidomonas delicatula and Dunaliella salina were tested. The developed biosensor can distinguish clearly between the living microalgae cells and the dead microalgae cells. The smallest microalgae cells that can be detected by using this biosensor are 3 μm ones. Even smaller microalgae cells could be detected by increasing the excitation light power. The developed microfluidic biosensor has great potential for in situ ballast water analysis.

  20. Direct and Sensitive Detection of CWA Simulants by Active Capillary Plasma Ionization Coupled to a Handheld Ion Trap Mass Spectrometer

    Science.gov (United States)

    Wolf, Jan-Christoph; Etter, Raphael; Schaer, Martin; Siegenthaler, Peter; Zenobi, Renato

    2016-07-01

    An active capillary plasma ionization (ACI) source was coupled to a handheld mass spectrometer (Mini 10.5; Aston Labs, West Lafayette, IN, USA) and applied to the direct gas-phase detection and quantification of chemical warfare agent (CWA) related chemicals. Complementing the discontinuous atmospheric pressure interface (DAPI) of the Mini 10.5 mass spectrometer with an additional membrane pump, a quasi-continuous sample introduction through the ACI source was achieved. Nerve agent simulants (three dialkyl alkylphosphonates, a dialkyl phosporamidate, and the pesticide dichlorvos) were detected at low gas-phase concentrations with limits of detection ranging from 1.0 μg/m3 to 6.3 μg/m3. Our results demonstrate a sensitivity enhancement for portable MS-instrumentation by using an ACI source, enabling direct, quantitative measurements of volatile organic compounds. Due to its high sensitivity, selectivity, low power consumption (<80 W) and weight (<13 kg), this instrumentation has the potential for direct on-site CWA detection as required by military or civil protection.

  1. Rapid and Sensitive Detection of Breast Cancer Cells in Patient Blood with Nuclease-Activated Probe Technology

    Directory of Open Access Journals (Sweden)

    Sven Kruspe

    2017-09-01

    Full Text Available A challenge for circulating tumor cell (CTC-based diagnostics is the development of simple and inexpensive methods that reliably detect the diverse cells that make up CTCs. CTC-derived nucleases are one category of proteins that could be exploited to meet this challenge. Advantages of nucleases as CTC biomarkers include: (1 their elevated expression in many cancer cells, including cells implicated in metastasis that have undergone epithelial-to-mesenchymal transition; and (2 their enzymatic activity, which can be exploited for signal amplification in detection methods. Here, we describe a diagnostic assay based on quenched fluorescent nucleic acid probes that detect breast cancer CTCs via their nuclease activity. This assay exhibited robust performance in distinguishing breast cancer patients from healthy controls, and it is rapid, inexpensive, and easy to implement in most clinical labs. Given its broad applicability, this technology has the potential to have a substantive impact on the diagnosis and treatment of many cancers. Keywords: cancer, circulating tumor cells, diagnostic nucleic acids, nucleases, diagnostic markers, breast cancer, liquid biopsy

  2. Development of Sensor Cells Using NF-κB Pathway Activation for Detection of Nanoparticle-Induced Inflammation

    Directory of Open Access Journals (Sweden)

    Akiyoshi Taniguchi

    2011-07-01

    Full Text Available The increasing use of nanomaterials in consumer and industrial products has aroused concerns regarding their fate in biological systems. An effective detection method to evaluate the safety of bio-nanomaterials is therefore very important. Titanium dioxide (TiO2, which is manufactured worldwide in large quantities for use in a wide range of applications, including pigment and cosmetic manufacturing, was once thought to be an inert material, but recently, more and more studies have indicated that TiO2 nanoparticles (TiO2 NPs can cause inflammation and be harmful to humans by causing lung and brain problems. In order to evaluate the safety of TiO2 NPs for the environment and for humans, sensor cells for inflammation detection were developed, and these were transfected with the Toll-like receptor 4 (TLR4 gene and Nuclear Factor Kappa B (NF-κB reporter gene. NF-κB as a primary cause of inflammation has received a lot of attention, and it can be activated by a wide variety of external stimuli. Our data show that TiO2 NPs-induced inflammation can be detected by our sensor cells through NF-κB pathway activation. This may lead to our sensor cells being used for bio-nanomaterial safety evaluation.

  3. Immuno-Detection of C3a, a C3 Complement Activated Product in Mastitis Milk, a Potential Diagnostic Marker.

    Science.gov (United States)

    Jacob, Thanislass; Subramani, Gangasudan; Sivaprakasam, Prathiba; Xavier, Antony P; Mukhopadhyay, Hirak K

    2017-02-23

    The sub-clinical form of mastitis is difficult to detect and causes huge economic loss to the dairy industry. It has become a threat to public health at large, thus there is a need for definite diagnosis of the disease. Therefore, this study was undertaken to identify the novel diagnostic marker for the detection of the sub-clinical form of mastitis. Two-dimensional gel analysis of the whey protein fraction of normal and mastitis milk samples revealed the presence of proteose peptone component 3 precursor, Trypsin precursor, complement component-C3, Ig heavy chain precursors and a C-type lectin domain as differentially expressed protein during the early stage of mastitis. Of these proteins identified, complement component-C3 was tested for its diagnostic potential. Western blot analysis of the milk whey of sub-clinical mastitis cases (M+, M++ & M+++) identified the accumulation of C3a, an activated product of complement component-C3. Further, the hemolytic activity of the above milk whey samples positively correlated with the somatic cell count. As C3a is already reported as an anaphylotoxic agent, it chemo tactically attracts lymphocytes at the site of inflammation, the detection of which in the milk whey can be of diagnostic importance for sub-clinical mastitis.

  4. A Vehicle Active Safety Model: Vehicle Speed Control Based on Driver Vigilance Detection Using Wearable EEG and Sparse Representation.

    Science.gov (United States)

    Zhang, Zutao; Luo, Dianyuan; Rasim, Yagubov; Li, Yanjun; Meng, Guanjun; Xu, Jian; Wang, Chunbai

    2016-02-19

    In this paper, we present a vehicle active safety model for vehicle speed control based on driver vigilance detection using low-cost, comfortable, wearable electroencephalographic (EEG) sensors and sparse representation. The proposed system consists of three main steps, namely wireless wearable EEG collection, driver vigilance detection, and vehicle speed control strategy. First of all, a homemade low-cost comfortable wearable brain-computer interface (BCI) system with eight channels is designed for collecting the driver's EEG signal. Second, wavelet de-noising and down-sample algorithms are utilized to enhance the quality of EEG data, and Fast Fourier Transformation (FFT) is adopted to extract the EEG power spectrum density (PSD). In this step, sparse representation classification combined with k-singular value decomposition (KSVD) is firstly introduced in PSD to estimate the driver's vigilance level. Finally, a novel safety strategy of vehicle speed control, which controls the electronic throttle opening and automatic braking after driver fatigue detection using the above method, is presented to avoid serious collisions and traffic accidents. The simulation and practical testing results demonstrate the feasibility of the vehicle active safety model.

  5. Detection of Tuberculosis Infection Hotspots Using Activity Spaces Based Spatial Approach in an Urban Tokyo, from 2003 to 2011.

    Science.gov (United States)

    Izumi, Kiyohiko; Ohkado, Akihiro; Uchimura, Kazuhiro; Murase, Yoshiro; Tatsumi, Yuriko; Kayebeta, Aya; Watanabe, Yu; Ishikawa, Nobukatsu

    2015-01-01

    Identifying ongoing tuberculosis infection sites is crucial for breaking chains of transmission in tuberculosis-prevalent urban areas. Previous studies have pointed out that detection of local accumulation of tuberculosis patients based on their residential addresses may be limited by a lack of matching between residences and tuberculosis infection sites. This study aimed to identify possible tuberculosis hotspots using TB genotype clustering statuses and a concept of "activity space", a place where patients spend most of their waking hours. We further compared the spatial distribution by different residential statuses and describe urban environmental features of the detected hotspots. Culture-positive tuberculosis patients notified to Shinjuku city from 2003 to 2011 were enrolled in this case-based cross-sectional study, and their demographic and clinical information, TB genotype clustering statuses, and activity space were collected. Spatial statistics (Global Moran's I and Getis-Ord Gi* statistics) identified significant hotspots in 152 census tracts, and urban environmental features and tuberculosis patients' characteristics in these hotspots were assessed. Of the enrolled 643 culture-positive tuberculosis patients, 416 (64.2%) were general inhabitants, 42 (6.5%) were foreign-born people, and 184 were homeless people (28.6%). The percentage of overall genotype clustering was 43.7%. Genotype-clustered general inhabitants and homeless people formed significant hotspots around a major railway station, whereas the non-clustered general inhabitants formed no hotspots. This suggested the detected hotspots of activity spaces may reflect ongoing tuberculosis transmission sites and were characterized by smaller residential floor size and a higher proportion of non-working households. Activity space-based spatial analysis suggested possible TB transmission sites around the major railway station and it can assist in further comprehension of TB transmission dynamics in an

  6. In vivo detection of activated platelets allows characterizing rupture of atherosclerotic plaques with molecular magnetic resonance imaging in mice.

    Directory of Open Access Journals (Sweden)

    Dominik von Elverfeldt

    Full Text Available BACKGROUND: Early and non-invasive detection of platelets on micro atherothrombosis provides a means to identify unstable plaque and thereby allowing prophylactic treatment towards prevention of stroke or myocardial infarction. Molecular magnetic resonance imaging (mMRI of activated platelets as early markers of plaque rupture using targeted contrast agents is a promising strategy. In this study, we aim to specifically image activated platelets in murine atherothrombosis by in vivo mMRI, using a dedicated animal model of plaque rupture. METHODS: An antibody targeting ligand-induced binding sites (LIBS on the glycoprotein IIb/IIIa-receptor of activated platelets was conjugated to microparticles of iron oxide (MPIO to form the LIBS-MPIO contrast agent causing a signal-extinction in T2*-weighted MRI. ApoE(-/- mice (60 weeks-old were fed a high fat diet for 5 weeks. Using a small needle, the surface of their carotid plaques was scratched under blood flow to induce atherothrombosis. In vivo 9.4 Tesla MRI was performed before and repetitively after intravenous injection of either LIBS-MPIO versus non-targeted-MPIO. RESULTS: LIBS-MPIO injected animals showed a significant signal extinction (p<0.05 in MRI, corresponding to the site of plaque rupture and atherothrombosis in histology. The signal attenuation was effective for atherothrombosis occupying ≥ 2% of the vascular lumen. Histology further confirmed significant binding of LIBS-MPIO compared to control-MPIO on the thrombus developing on the surface of ruptured plaques (p<0.01. CONCLUSION: in vivo mMRI detected activated platelets on mechanically ruptured atherosclerotic plaques in ApoE(-/- mice with a high sensititvity. This imaging technology represents a unique opportunity for noninvasive detection of atherothrombosis and the identification of unstable atherosclerotic plaques with the ultimate promise to prevent strokes and myocardial infarctions.

  7. Consumer participation in early detection of the deteriorating patient and call activation to rapid response systems: a literature review.

    Science.gov (United States)

    Vorwerk, Jane; King, Lindy

    2016-01-01

    This review investigated the impact of consumer participation in recognition of patient deterioration and response through call activation in rapid response systems. Nurses and doctors have taken the main role in recognition and response to patient deterioration through hospital rapid response systems. Yet patients and visitors (consumers) have appeared well placed to notice early signs of deterioration. In response, many hospitals have sought to partner health professionals with consumers in detection and response to early deterioration. However, to date, there have been no published research-based reviews to establish the impact of introducing consumer involvement into rapid response systems. A critical research-based review was undertaken. A comprehensive search of databases from 2006-2014 identified 11 studies. Critical appraisal of these studies was undertaken and thematic analysis of the findings revealed four major themes. Following implementation of the consumer activation programmes, the number of calls made by the consumers following detection of deterioration increased. Interestingly, the number of staff calls also increased. Importantly, mortality numbers were found to decrease in one major study following the introduction of consumer call activation. Consumer and staff knowledge and satisfaction with the new programmes indicated mixed results. Initial concerns of the staff over consumer involvement overwhelming the rapid response systems did not eventuate. Evaluation of successful consumer-activated programmes indicated the importance of: effective staff education and training; ongoing consumer education by nurses and clear educational materials. Findings indicated positive patient outcomes following introduction of consumer call activation programmes within rapid response systems. Effective consumer programmes included information that was readily accessible, easy-to-understand and available in a range of multimedia materials accompanied by the

  8. Dual core quantum dots for highly quantitative ratiometric detection of trypsin activity in cystic fibrosis patients

    Science.gov (United States)

    Castelló Serrano, Iván; Stoica, Georgiana; Matas Adams, Alba; Palomares, Emilio

    2014-10-01

    We present herein two colour encoded silica nanospheres (2nanoSi) for the fluorescence quantitative ratiometric determination of trypsin in humans. Current detection methods for cystic fibrosis diagnosis are slow, costly and suffer from false positives. The 2nanoSi proved to be a highly sensitive, fast (minutes), and single-step approach nanosensor for the screening and diagnosis of cystic fibrosis, allowing the quantification of trypsin concentrations in a wide range relevant for clinical applications (25-350 μg L-1). Furthermore, as trypsin is directly related to the development of cystic fibrosis (CF), different human genotypes, i.e. CF homozygotic, CF heterozygotic, and unaffected, respectively, can be determined using our 2nanoSi nanospheres. We anticipate the 2nanoSi system to be a starting point for non-invasive, easy-to-use and cost effective ratiometric fluorescent biomarkers for recessive genetic diseases like human cystic fibrosis. In a screening program in which the goal is to detect disease and also the carrier status, early diagnosis could be of great help.We present herein two colour encoded silica nanospheres (2nanoSi) for the fluorescence quantitative ratiometric determination of trypsin in humans. Current detection methods for cystic fibrosis diagnosis are slow, costly and suffer from false positives. The 2nanoSi proved to be a highly sensitive, fast (minutes), and single-step approach nanosensor for the screening and diagnosis of cystic fibrosis, allowing the quantification of trypsin concentrations in a wide range relevant for clinical applications (25-350 μg L-1). Furthermore, as trypsin is directly related to the development of cystic fibrosis (CF), different human genotypes, i.e. CF homozygotic, CF heterozygotic, and unaffected, respectively, can be determined using our 2nanoSi nanospheres. We anticipate the 2nanoSi system to be a starting point for non-invasive, easy-to-use and cost effective ratiometric fluorescent biomarkers for

  9. Detection of Drug Effects on Brain Activity using EEG-P300 with Similar Stimuli

    Science.gov (United States)

    Turnip, Arjon; Dwi Esti, K.; Faizal Amri, M.; Simbolon, Artha I.; Agung Suhendra, M.; IsKandar, Shelly; Wirakusumah, Firman F.

    2017-07-01

    Drug addiction poses a serious problem to our species. The worry that our significant family might be involved in drug use and are concerned to know how to detect drug use. Examinations of thirty taped EEG recordings were performed. The subjects consist of three group: addictive, methadone treatment (rehabilitation), and control (normal) which 10 subjects for each group. Statistical analysis was performed for the relative frequency of wave bands. The higher average amplitude is obtained from the addiction subjects. In the comparison with the signals source, channels P3 provide slightly higher average amplitude than other channels for all of subjects.

  10. An open source cryostage and software analysis method for detection of antifreeze activity

    DEFF Research Database (Denmark)

    Lørup Buch, Johannes; Ramløv, H

    2016-01-01

    The aim of this study is to provide the reader with a simple setup that can detect antifreeze proteins (AFP) by inhibition of ice recrystallisation in very small sample sizes. This includes an open source cryostage, a method for preparing and loading samples as well as a software analysis method....... The entire setup was tested using hyperactive AFP from the cerambycid beetle, Rhagium mordax. Samples containing AFP were compared to buffer samples, and the results are visualised as crystal radius evolution over time and in absolute change over 30 min. Statistical analysis showed that samples containing...

  11. E4 antibodies facilitate detection and type-assignment of active HPV infection in cervical disease.

    Directory of Open Access Journals (Sweden)

    Heather Griffin

    Full Text Available High-risk human papillomavirus (HPV infections are the cause of nearly all cases of cervical cancer. Although the detection of HPV DNA has proved useful in cervical diagnosis, it does not necessarily predict disease presence or severity, and cannot conclusively identify the causative type when multiple HPVs are present. Such limitations may be addressed using complementary approaches such as cytology, laser capture microscopy, and/or the use of infection biomarkers. One such infection biomarker is the HPV E4 protein, which is expressed at high level in cells that are supporting (or have supported viral genome amplification. Its distribution in lesions has suggested a role in disease staging. Here we have examined whether type-specific E4 antibodies may also allow the identification and/or confirmation of causal HPV-type. To do this, type-specific polyclonal and monoclonal antibodies against three E4 proteins (HPV-16, -18, and -58 were generated and validated by ELISA and western blotting, and by immunohistochemistry (IHC staining of epithelial rafts containing these individual HPV types. Type-specific detection of HPV and its associated disease was subsequently examined using formalin-fixed paraffin-embedded cervical intra-epithelial neoplasias (CIN, (n = 247 and normal controls (n = 28. All koilocytotic CIN1 lesions showed type-specific E4 expression of their respective HPV types. Differences were noted amongst E4 expression patterns in CIN3. HPV-18 E4 was not detected in any of the 6 HPV-18 DNA-positive CIN3 lesions examined, whereas in HPV-16 and -58 CIN3, 28/37 (76% and 5/9 (55.6% expressed E4 respectively, usually in regions of epithelial differentiation. Our results demonstrate that type-specific E4 antibodies can be used to help establish causality, as may be required when multiple HPV types are detected. The unique characteristics of the E4 biomarker suggest a role in diagnosis and patient management particularly when used in combination.

  12. Influence of surface active agents on the detection of beta radiation

    International Nuclear Information System (INIS)

    Mesquita, T.B.; Ruegg, E.F.

    1984-01-01

    It has been studied the efficiency of beta irradiation detection by liquid scintillation counting using the pesticide 14 C-lindane as radiation source and scientillation cocktails containing Triton-X, Arkopal, Tinoventin, Extravon-200, Oswalmida, Bigral, ethanol and methanol. Excepting the last 5 products, which led to a phase formation in the mixture, all other compounds, that are easily available in the local market, proved to be good substitute products for the well known Triton-X, an expensive and restrict emulsifier used for liquid scintillation measurement of aqueous solutions. (Author) [pt

  13. Carbon dots for fluorescent detection of α-glucosidase activity using enzyme activated inner filter effect and its application to anti-diabetic drug discovery

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Weiheng [Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165 (China); Wu, Di [School of Life Sciences, Xiamen University, Xiamen 361005 (China); Xia, Lian [Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165 (China); Chen, Xuefeng [School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xian 710021 (China); Li, Guoliang, E-mail: 61254368@163.com [School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xian 710021 (China); Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165 (China); Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Centre for Food Safety Risk Assessment, Beijing 100021 (China); Qiu, Nannan [Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Centre for Food Safety Risk Assessment, Beijing 100021 (China); Chen, Guang; Sun, Zhiwei; You, Jinmao [Key Laboratory of Life-Organic Analysis of Shandong Province, Qufu Normal University, Qufu 273165 (China); Wu, Yongning, E-mail: wuyongning@cfsa.net.cn [Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Centre for Food Safety Risk Assessment, Beijing 100021 (China)

    2017-06-22

    Recently, α-glucosidase inhibitor has been widely used in clinic for diabetic therapy. In the present study, a facile and sensitive fluorescent assay based on enzyme activated inner filter effect (IFE) on nitrogen-doped carbon dots (CDs) was first developed for the detection of α-glucosidase. The N-doped CDs with green emission were prepared by a one-step hydrothermal synthesis and gave the fluorescence quantum yield of 30%, which were used as the signal output. Through α-glucosidase catalysis, 4-nitrophenol was released from 4-nitrophenyl-α-D-glucopyranoside (NGP). Interestingly, the absorption of 4-nitrophenol and the excitation of CDs were completely overlapping. Due to its great molar absorptivity, 4-nitrophenol was capable of acting as a powerful absorber to affect the fluorescent signal of CDs (i.e. IFE). By converting the absorption signals into fluorescence signals, the facile fluorescence assay strategy could be realized for α-glucosidase activity sensing, which effectively avoided the complex modification of the surface of CDs or construction of the nanoprobes. The established IFE-based sensing platform offered a low detection limit of 0.01 U/mL (S/N = 3). This proposed sensing approach has also been expanded to the inhibitor screening and showed excellent applicability. As a typical α-glucosidase inhibitor, acarbose was investigated with a low detection limit of 10{sup −8} M. This developed method enjoyed many merits including simplicity, lost cost, high sensitivity, good reproducibility and excellent selectivity, which also provided a new insight on the application of CDs to develop the facile and sensitive biosensor. - Highlights: • Green N-doped CDs were first prepared by a facile synthesis process. • IFE-based sensor without covalent linking or surface modifications was developed. • The method was successfully applied to α-glucosidase detection. • The method can be employed for sensitive screening of anti-diabetes drugs.

  14. Detection of Interfacial Debonding in a Rubber-Steel-Layered Structure Using Active Sensing Enabled by Embedded Piezoceramic Transducers.

    Science.gov (United States)

    Feng, Qian; Kong, Qingzhao; Jiang, Jian; Liang, Yabin; Song, Gangbing

    2017-09-01

    Rubber-steel-layered structures are used in many engineering applications. Laminated rubber-steel bearing, as a type of seismic isolation device, is one of the most important applications of the rubber-steel-layered structures. Interfacial debonding in rubber-steel-layered structures is a typical failure mode, which can severely reduce their load-bearing capacity. In this paper, the authors developed a simple but effective active sensing approach using embedded piezoceramic transducers to provide an in-situ detection of the interfacial debonding between the rubber layers and steel plates. A sandwiched rubber-steel-layered specimen, consisting of one rubber layer and two steel plates, was fabricated as the test specimen. A novel installation technique, which allows the piezoceramic transducers to be fully embedded into the steel plates without changing the geometry and the surface conditions of the plates, was also developed in this research. The active sensing approach, in which designed stress waves can propagate between a pair of the embedded piezoceramic transducers (one as an actuator and the other one as a sensor), was employed to detect the steel-rubber debonding. When the rubber-steel debonding occurs, the debonded interfaces will attenuate the propagating stress wave, so that the amplitude of the received signal will decrease. The rubber-steel debonding was generated by pulling the two steel plates in opposite directions in a material-testing machine. The changes of the received signal before and after the debonding were characterized in a time domain and further quantified by using a wavelet packet-based energy index. Experiments on the healthy rubber-steel-layered specimen reveal that the piezoceramic-induced stress wave can propagate through the rubber layer. The destructive test on the specimen demonstrates that the piezoceramic-based active sensing approach can effectively detect the rubber-steel debonding failure in real time. The active sensing

  15. Detection of Interfacial Debonding in a Rubber–Steel-Layered Structure Using Active Sensing Enabled by Embedded Piezoceramic Transducers

    Science.gov (United States)

    Feng, Qian; Jiang, Jian; Liang, Yabin; Song, Gangbing

    2017-01-01

    Rubber–steel-layered structures are used in many engineering applications. Laminated rubber–steel bearing, as a type of seismic isolation device, is one of the most important applications of the rubber–steel-layered structures. Interfacial debonding in rubber–steel-layered structures is a typical failure mode, which can severely reduce their load-bearing capacity. In this paper, the authors developed a simple but effective active sensing approach using embedded piezoceramic transducers to provide an in-situ detection of the interfacial debonding between the rubber layers and steel plates. A sandwiched rubber–steel-layered specimen, consisting of one rubber layer and two steel plates, was fabricated as the test specimen. A novel installation technique, which allows the piezoceramic transducers to be fully embedded into the steel plates without changing the geometry and the surface conditions of the plates, was also developed in this research. The active sensing approach, in which designed stress waves can propagate between a pair of the embedded piezoceramic transducers (one as an actuator and the other one as a sensor), was employed to detect the steel–rubber debonding. When the rubber–steel debonding occurs, the debonded interfaces will attenuate the propagating stress wave, so that the amplitude of the received signal will decrease. The rubber–steel debonding was generated by pulling the two steel plates in opposite directions in a material-testing machine. The changes of the received signal before and after the debonding were characterized in a time domain and further quantified by using a wavelet packet-based energy index. Experiments on the healthy rubber–steel-layered specimen reveal that the piezoceramic-induced stress wave can propagate through the rubber layer. The destructive test on the specimen demonstrates that the piezoceramic-based active sensing approach can effectively detect the rubber–steel debonding failure in real time. The

  16. KOI-676: An active star with two transiting planets and a third possible candidate detected with TTV

    Science.gov (United States)

    Ioannidis, P.; Schmitt, J.; Avdellidou, C.; von Essen, C.; Eric, A.

    2013-09-01

    We report the detection and characterization of two short period, Neptune sized planets, around the active star KOI-676. The orbital elements of both planets are not the expected ones, as they lead to miscalculation of the stellar parameters. We discuss various scenarios which could cause that discrepancy and we suggest that the reason is most probably the high eccentricities of the orbits. We use the Transit Timing Variations, detected in both planets' O-C diagrams to support our theory, while due to the lack of autocorrelation in their pattern we suggest the existence of a third, more massive, mutual inclined, outer perturber. To clarify our suggestions we use n-body simulations to model the TTVs and check the stability of the system.

  17. Simultaneous determination of active ingredients in Erigeron breviscapus (Vant.) Hand-Mazz. by capillary electrophoresis with electrochemical detection.

    Science.gov (United States)

    Chu, Qingcui; Wu, Ting; Fu, Liang; Ye, Jiannong

    2005-03-09

    A high-performance capillary electrophoresis (CE) with electrochemical detection (ED) method was developed for the determination of the pharmacologically active ingredients in Erigeron breviscapus (Vant.) Hand-Mazz. and its extract phytopharmaceuticals in this work. Under the optimum conditions, nine analytes, baicalein, naringenin, scopoletin, kaempferol, apigenin, scutellarin, luteolin, caffeic acid and protocatechuic acid were separated within 24 min in a borax buffer (pH 8.7). Notably, excellent linearity was obtained over two orders of magnitude with detection limits (S/N=3) ranged from 1.0 x 10(-7) g/mL to 5.6 x 10(-7) g/mL for all nine analytes. This method was successfully used in the analysis of E. breviscapus (Vant.) Hand-Mazz. and its phytopharmaceuticals with a relatively simple extraction procedure, and the assay results were satisfactory.

  18. An Online Change of Activity in Energy Spectrum for Detection on an Early Intervention Robot

    Energy Technology Data Exchange (ETDEWEB)

    Boudergui, K.; Laine, F. [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, F-91191 Gif Sur Yvette (France); Montagu, T. [CEA, LIST, Laboratoire de Modelisation et de Simulation des Systemes, 91191 Gif-sur-Yvette (France); Blanc, P. [IMS, Innovation and Measurement Systems, 94100 Saint-Maur-des-Fosses (France); Deltour, A. [ECA Robotics, 91892 Orsay Cedex (France); Mozziconacci, S. [SDIS13, 13110 Port de Bouc (France)

    2015-07-01

    With the growth of industrial risks and the multiplication of CBRNe (Chemical Biological Radiological and explosive) attacks through toxic chemicals, biological or radiological threats, public services and military authorities face with increasingly critical situations, whose management is strongly conditioned by fast and reliable establishment of an informative diagnostic. Right after an attack, the five first minutes are crucial to define the various scenarios and the most dangerous for a human intervention. Therefore the use of robots is considered essential by all stakeholders of security. In this context, the SISPEO project (Systeme d'Intervention Sapeurs Pompiers Robotise) aims to create/build/design a robust response through a robotic platform for early intervention services such as civil and military security in hostile environments. CEA LIST has proposed an adapted solution to detect and characterize nuclear and radiological risks online and in motion, using a miniature embedded CdZnTe (CZT) crystal Gamma-ray spectrometer. This paper presents experimental results for this miniature embedded CZT spectrometer and its associated mathematical method to detect and characterize radiological threats online and in motion. (authors)

  19. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    Directory of Open Access Journals (Sweden)

    Dongxia Li

    2015-05-01

    Full Text Available A total of 59 lactic acid bacteria (LAB strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L. plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C, but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0, but became inactive under neutral and alkaline condition (pH 7.0 to 9.0. In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

  20. Detecting internet activity for erectile dysfunction using search engine query data in the Republic of Ireland.

    Science.gov (United States)

    Davis, Niall F; Smyth, Lisa G; Flood, Hugh D

    2012-12-01

    What's known on the subject? and What does the study add? Despite the increasing prevalence of erectile dysfunction (ED), there is reluctance among symptomatic patients to present to healthcare providers for appropriate advice and treatment. A number of Internet campaigns have been launched by the Irish healthcare media since 2007 aiming to provide easily accessible advice on ED. Novel online technologies appear to provide a useful tool for educating the general public on the symptoms of ED because there has been a significant increase in overall Internet search activity for this term since 2007. • To assess Internet search trends for erectile dysfunction (ED) subsequent to public awareness campaigns being launched within the Republic of Ireland • To assess whether the advent of such campaigns correlates with increased Internet search activity for ED. • Google insights for search was utilized to examine Internet search trends for the term 'erectile dysfunction' across all categories between January 2005 and December 2011. • Search activity was limited to users from the Republic of Ireland within this timeframe. • Additionally, the number of Irish Internet media campaigns and Irish web pages providing information on ED was assessed between January 2005 and December 2011. • Statistical analysis of the data was performed using analysis of variance and Student's t-tests for pairwise comparisons. • There has been a significant increase in mean search activity for ED on an annual basis since 2007 (P search activity for ED from 2005 to 2007 • The advent of recent Internet media campaigns and increasing number of Irish web pages is associated with a significant increase in online activity for ED in the Republic of Ireland. • Novel online technologies appear to provide a useful tool for educating the general public on the symptoms and treatment options available for ED. © 2012 BJU INTERNATIONAL.

  1. Zymography Detection of a Bacterial Extracellular Thermoalkaline Esterase/Lipase Activity.

    Science.gov (United States)

    Tapizquent, María; Fernández, Marleny; Barreto, Georgina; Hernández, Zully; Contreras, Lellys M; Kurz, Liliana; Wilkesman, Jeff

    2017-01-01

    Lipases are esterases that occur widely in nature, yet those with commercial relevance are exclusively from microbial origin. Glycerol and long-chain fatty acids are the products after hydrolysis of esters bonds in saponifiable lipids catalyzed by lipases. In this work, we describe lipase/esterase activity contained in cell-free fractions from thermophilic bacteria, cultured in medium containing olive oil. Analysis of the cell-free fractions by electrotransference zymography, using tributyrin as substrate, revealed bands corresponding to lipase activity. The method is simple, fast, and inexpensive.

  2. Evidence for the expression of native Mycobacterium tuberculosis phospholipase C: recognition by immune sera and detection of promoter activity

    Directory of Open Access Journals (Sweden)

    Matsui T.

    2000-01-01

    Full Text Available The genome of Mycobacterium tuberculosis H37Rv contains three contiguous genes (plc-a, plc-b and plc-c which are similar to the Pseudomonas aeruginosa phospholipase C (PLC genes. Expression of mycobacterial PLC-a and PLC-b in E. coli and M. smegmatis has been reported, whereas expression of the native proteins in M. tuberculosis H37Rv has not been demonstrated. The objective of the present study was to demonstrate that native PLC-a is expressed in M. tuberculosis H37Rv. Sera from mice immunized with recombinant PLC-a expressed in E. coli were used in immunoblots to evaluate PLC-a expression. The immune serum recognized a 49-kDa protein in immunoblots against M. tuberculosis extracts. No bands were visible in M. tuberculosis culture supernatants or extracts from M. avium, M. bovis and M. smegmatis. A 550-bp DNA fragment upstream of plc-a was cloned in the pJEM12 vector and the existence of a functional promoter was evaluated by detection of ß-galactosidase activity. ß-Galactosidase activity was detected in M. smegmatis transformed with recombinant pJEM12 grown in vitro and inside macrophages. The putative promoter was active both in vitro and in vivo, suggesting that expression is constitutive. In conclusion, expression of non-secreted native PLC-a was demonstrated in M. tuberculosis.

  3. Differences in the location and activity of intestinal Crohn's disease lesions between adult and paediatric patients detected with MRI

    International Nuclear Information System (INIS)

    Maccioni, Francesca; Carrozzo, Federica; Pino, Anna Rosaria; Staltari, Ilaria; Ansari, Najwa Al; Marini, Mario; Viola, Franca; Di Nardo, Giovanni; Cucchiara, Salvatore; Vestri, Annarita; Signore, Alberto

    2012-01-01

    To prospectively compare paediatric patients (PP) and adult patients (AP) affected by Crohn's disease (CD) in terms of the location and activity of intestinal lesions. Forty-three children (mean age 15 years) and 43 adults (mean age 48 years) with proven CD underwent magnetic resonance enterography (MRE) to localise lesions and detect their activity in 9 segments of the small and large bowel. The results were analysed on a per patient and per segment basis. Ileo-colonoscopy was performed in all patients. P values less than 0.05 were considered statistically significant. Involvement of terminal ileum was significantly different in the two groups: observed in 100 % of AP (43/43) versus 58 % (23/43) of PP (P < 0.0001). Conversely, the colon was diseased in 84 % of PP versus 64 % of AP. In particular, left colonic segments were significantly more involved in PP (descending colon 53 % versus 21 %, P < 0.01; rectum 67 % versus 23 %, P < 0.0001; sigmoid colon 56 % versus 37 %, not significant), whereas caecal involvement was equal in both groups. In children the maximal disease activity was found in left colonic segments, whereas in adults it was in the terminal ileum. MRE detected significant differences between the two populations, showing a more extensive and severe involvement of the left colon in children but the distal ileum in adults. (orig.)

  4. Fast detection of peroxidase (POD) activity in tomato leaves which infected with Botrytis cinerea using hyperspectral imaging

    Science.gov (United States)

    Kong, Wenwen; Liu, Fei; Zhang, Chu; Bao, Yidan; Yu, Jiajia; He, Yong

    2014-01-01

    Tomatoes are cultivated around the world and gray mold is one of its most prominent and destructive diseases. An early disease detection method can decrease losses caused by plant diseases and prevent the spread of diseases. The activity of peroxidase (POD) is very important indicator of disease stress for plants. The objective of this study is to examine the possibility of fast detection of POD activity in tomato leaves which infected with Botrytis cinerea using hyperspectral imaging data. Five pre-treatment methods were investigated. Genetic algorithm-partial least squares (GA-PLS) was applied to select optimal wavelengths. A new fast learning neural algorithm named extreme learning machine (ELM) was employed as multivariate analytical tool in this study. 21 optimal wavelengths were selected by GA-PLS and used as inputs of three calibration models. The optimal prediction result was achieved by ELM model with selected wavelengths, and the r and RMSEP in validation were 0.8647 and 465.9880 respectively. The results indicated that hyperspectral imaging could be considered as a valuable tool for POD activity prediction. The selected wavelengths could be potential resources for instrument development.

  5. Interleukin 2 secretion by T cells for detection of biologically active Staphylococcal enterotoxin type E

    Science.gov (United States)

    Staphylococcus aureus is a significant worldwide source of clinical infections and foodborne illnesses acting through the synthesis of a group of enterotoxins (SEs) which cause gastroenteritis and also function as superantigens that activate T cells resulting in massive cytokine production yielding ...

  6. IDENTIFYING RECENT SURFACE MINING ACTIVITIES USING A NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI) CHANGE DETECTION METHOD

    Science.gov (United States)

    Coal mining is a major resource extraction activity on the Appalachian Mountains. The increased size and frequency of a specific type of surface mining, known as mountain top removal-valley fill, has in recent years raised various environmental concerns. During mountainto...

  7. Morphometric alterations, steatosis, fibrosis and active caspase-3 detection in carbamate bendiocarb treated rabbit liver

    Czech Academy of Sciences Publication Activity Database

    Petrovová, E.; Purzyc, H.; Mazenský, D.; Luptáková, L.; Torma, N.; Sopoliga, I.; Sedmera, David

    2015-01-01

    Roč. 30, č. 2 (2015), s. 212-222 ISSN 1520-4081 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : bendiocarb * caspase-3 activity * fibrosis * toxicity * rabbit * liver Subject RIV: EA - Cell Biology Impact factor: 2.868, year: 2015

  8. On-slide detection of enzymatic activities in selected single cells

    DEFF Research Database (Denmark)

    Keller, Josephine Geertsen; Tesauro, Cinzia; Coletta, Andrea

    2017-01-01

    With increasing recognition of the importance in addressing cell-to-cell heterogeneity for the understanding of complex biological systems, there is a growing need for assays capable of single cell analyses. In the current study, we describe the measurement of human topoisomerase I activity in si...

  9. Rapprochement between Active Fault Diagnosis and Change Detection in ARMAX Systems

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad; Niemann, Hans Henrik

    2006-01-01

    The connection between AFD (Active Fault Diagnosis), ARMAX systems and RST controllers etc. are considered in this paper. It is shown that the applied setup in modern AFD for closed loop systems can be considered as a generalization of the setup used in connection with traditional methods...

  10. Detection of Molecular Chirality by Induced Resonance Raman Optical Activity in Europium Complexes

    Czech Academy of Sciences Publication Activity Database

    Yamamoto, Shigeki; Bouř, Petr

    2012-01-01

    Roč. 51, č. 44 (2012), s. 11058-11061 ISSN 1433-7851 R&D Projects: GA MŠk(CZ) LH11033; GA ČR GAP208/11/0105 Institutional support: RVO:61388963 Keywords : europium * complexes * raman optical activity * resonance Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.734, year: 2012

  11. Detection of metals and polychlorobiphenyls and their correlation with detoxificant enzymes activity in Dicentrarchus labrax

    Directory of Open Access Journals (Sweden)

    I. Traversi

    2011-01-01

    Full Text Available Several pollutants released to the environment, are biotransformed into more soluble molecules, in liver, by several enzymes, as catalase (CAT and glutathione-S-tranferase (GST, which are fundamental for detoxification and excretion. The aim of this study was to investigate the relationships among xenobiotic levels and CAT and GST enzymatic activities, in reared European sea bass.

  12. Detection of lipoatrophy in human immunodeficiency virus-1-infected children treated with highly active antiretroviral therapy.

    NARCIS (Netherlands)

    Hartman, K.; Verweel, G.; Groot, R. de; Hartwig, N.G.

    2006-01-01

    BACKGROUND: Highly active antiretroviral therapy has been associated with lipodystrophy in adults. Much is unknown about its characteristics, especially in children. OBJECTIVE: To obtain an objective case definition of the lipodystrophy syndrome. METHODS: This was a cross-sectional study. One

  13. Detection of oral streptococci in dental biofilm from caries-active and caries-free children

    Science.gov (United States)

    da Silva, Andréa Cristina Barbosa; Cruz, Jader dos Santos; Sampaio, Fábio Correia; de Araújo, Demetrius Antônio Machado

    2008-01-01

    This work correlated the presence of oral streptococci in dental biofilm with clinical indexes of caries and oral hygiene in caries-active and caries-free children. S. mutans and/or S. sobrinus in the dental biofilm does not indicate a direct risk for developing dental caries. PMID:24031282

  14. Active pharmaceutical ingredients detected in herbal food supplements for weight loss samples on the Dutch market

    NARCIS (Netherlands)

    Reeuwijk, N.M.; Venhuis, B.J.; Kaste, de D.; Hoogenboom, L.A.P.; Rietjens, I.; Martena, M.J.

    2014-01-01

    Herbal food supplements claiming to reduce weight may contain active pharmacological ingredients (APIs) that can be used for the treatment of overweight and obesity. The aim of this study was to determine whether herbal food supplements for weight loss on the Dutch market contain APIs with weight

  15. Quantitative detection and biological propagation of scrapie seeding activity in vitro facilitate use of prions as model pathogens for disinfection.

    Directory of Open Access Journals (Sweden)

    Sandra Pritzkow

    Full Text Available Prions are pathogens with an unusually high tolerance to inactivation and constitute a complex challenge to the re-processing of surgical instruments. On the other hand, however, they provide an informative paradigm which has been exploited successfully for the development of novel broad-range disinfectants simultaneously active also against bacteria, viruses and fungi. Here we report on the development of a methodological platform that further facilitates the use of scrapie prions as model pathogens for disinfection. We used specifically adapted serial protein misfolding cyclic amplification (PMCA for the quantitative detection, on steel wires providing model carriers for decontamination, of 263K scrapie seeding activity converting normal protease-sensitive into abnormal protease-resistant prion protein. Reference steel wires carrying defined amounts of scrapie infectivity were used for assay calibration, while scrapie-contaminated test steel wires were subjected to fifteen different procedures for disinfection that yielded scrapie titre reductions of ≤10(1- to ≥10(5.5-fold. As confirmed by titration in hamsters the residual scrapie infectivity on test wires could be reliably deduced for all examined disinfection procedures, from our quantitative seeding activity assay. Furthermore, we found that scrapie seeding activity present in 263K hamster brain homogenate or multiplied by PMCA of scrapie-contaminated steel wires both triggered accumulation of protease-resistant prion protein and was further propagated in a novel cell assay for 263K scrapie prions, i.e., cerebral glial cell cultures from hamsters. The findings from our PMCA- and glial cell culture assays revealed scrapie seeding activity as a biochemically and biologically replicative principle in vitro, with the former being quantitatively linked to prion infectivity detected on steel wires in vivo. When combined, our in vitro assays provide an alternative to titrations of biological

  16. Fall Detection for Elderly from Partially Observed Depth-Map Video Sequences Based on View-Invariant Human Activity Representation

    Directory of Open Access Journals (Sweden)

    Rami Alazrai

    2017-03-01

    Full Text Available This paper presents a new approach for fall detection from partially-observed depth-map video sequences. The proposed approach utilizes the 3D skeletal joint positions obtained from the Microsoft Kinect sensor to build a view-invariant descriptor for human activity representation, called the motion-pose geometric descriptor (MPGD. Furthermore, we have developed a histogram-based representation (HBR based on the MPGD to construct a length-independent representation of the observed video subsequences. Using the constructed HBR, we formulate the fall detection problem as a posterior-maximization problem in which the posteriori probability for each observed video subsequence is estimated using a multi-class SVM (support vector machine classifier. Then, we combine the computed posteriori probabilities from all of the observed subsequences to obtain an overall class posteriori probability of the entire partially-observed depth-map video sequence. To evaluate the performance of the proposed approach, we have utilized the Kinect sensor to record a dataset of depth-map video sequences that simulates four fall-related activities of elderly people, including: walking, sitting, falling form standing and falling from sitting. Then, using the collected dataset, we have developed three evaluation scenarios based on the number of unobserved video subsequences in the testing videos, including: fully-observed video sequence scenario, single unobserved video subsequence of random lengths scenarios and two unobserved video subsequences of random lengths scenarios. Experimental results show that the proposed approach achieved an average recognition accuracy of 93 . 6 % , 77 . 6 % and 65 . 1 % , in recognizing the activities during the first, second and third evaluation scenario, respectively. These results demonstrate the feasibility of the proposed approach to detect falls from partially-observed videos.

  17. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    International Nuclear Information System (INIS)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs

  18. Environmental assessment of the thermal neutron activation explosive detection system for concourse use at US airports

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.G.

    1990-08-01

    This document is an environmental assessment of a system designed to detect the presence of explosives in checked airline baggage or cargo. The system is meant to be installed at the concourse or lobby ticketing areas of US commercial airports and uses a sealed radioactive source of californium-252 to irradiate baggage items. The major impact of the use of this system arises from direct exposure of the public to scattered or leakage radiation from the source and to induced radioactivity in baggage items. Under normal operation and the most likely accident scenarios, the environmental impacts that would be created by the proposed licensing action would not be significant. 44 refs., 19 figs., 18 tabs.

  19. Tandem Mass Spectrometry Detection of Quorum Sensing Activity in Multidrug Resistant Clinical Isolate Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2014-01-01

    Full Text Available Many Proteobacteria communicate via production followed by response of quorum sensing molecules, namely, N-acyl homoserine lactones (AHLs. These molecules consist of a lactone moiety with N-acyl side chain with various chain lengths and degrees of saturation at C-3 position. AHL-dependent QS is often associated with regulation of diverse bacterial phenotypes including the expression of virulence factors. With the use of biosensor and high resolution liquid chromatography tandem mass spectrometry, the AHL production of clinical isolate A. baumannii 4KT was studied. Production of short chain AHL, namely, N-hexanoyl-homoserine lactone (C6-HSL and N-octanoyl-homoserine lactone (C8-HSL, was detected.

  20. Basic Study of Defective Ammunition Detection by the Combination of PGNAA (Prompt Gamma-ray Neutron Activation Analysis) and Chemometrics

    International Nuclear Information System (INIS)

    Im, Hee Jung; Song, Byoung Chul; Shin, Jae Kon; Park, Yong Joon; Song, Kyu Seok

    2010-01-01

    We are interested in evaluating detection capability of defective ammunition in store for years even decades by using prompt gamma-ray neutron activation analysis (PGNAA) method. The PGNAA method can be used for multielemental analysis of ammunition to check the inner elemental composition changes. At first, in this study, instead of the real experimental gamma spectrum data from PGNAA, the gamma spectrum data from MCNP transport code simulation were obtained to observe discriminant classes for defective ammunition by adding 10% moisture. For this, the collected MCNP data were applied to principal component analysis (PCA) for the effective pattern recognition