23 research outputs found

    Comparative analysis of organophosphate degrading enzymes from diverse species

    Get PDF
    Different types of organophosphorous compounds constitute most potent pesticides. These chemicals attack the nervous system of living organisms causing death. Different organisms produce enzymes to degrade these chemicals. These enzymes are present in simple microorganisms from archaea, bacteria to complex eukaryotes like humans. A comparison of representative eight shortlisted enzymes involved in the degradation and inactivation of organophosphates from a wide range of organisms was performed to infer the basis of their common functionality. There is little sequence homology in these enzymes which results in divergent tertiary structures. The only feature that these enzymes seem to share is their amino acid composition. However, structural analysis has shown no significant similarities among this functionally similar group of organophosphate degrading enzymes

    Separating movement and gravity components in an acceleration signal and implications for the assessment of human daily physical activity.

    Get PDF
    INTRODUCTION: Human body acceleration is often used as an indicator of daily physical activity in epidemiological research. Raw acceleration signals contain three basic components: movement, gravity, and noise. Separation of these becomes increasingly difficult during rotational movements. We aimed to evaluate five different methods (metrics) of processing acceleration signals on their ability to remove the gravitational component of acceleration during standardised mechanical movements and the implications for human daily physical activity assessment. METHODS: An industrial robot rotated accelerometers in the vertical plane. Radius, frequency, and angular range of motion were systematically varied. Three metrics (Euclidian norm minus one [ENMO], Euclidian norm of the high-pass filtered signals [HFEN], and HFEN plus Euclidean norm of low-pass filtered signals minus 1 g [HFEN+]) were derived for each experimental condition and compared against the reference acceleration (forward kinematics) of the robot arm. We then compared metrics derived from human acceleration signals from the wrist and hip in 97 adults (22-65 yr), and wrist in 63 women (20-35 yr) in whom daily activity-related energy expenditure (PAEE) was available. RESULTS: In the robot experiment, HFEN+ had lowest error during (vertical plane) rotations at an oscillating frequency higher than the filter cut-off frequency while for lower frequencies ENMO performed better. In the human experiments, metrics HFEN and ENMO on hip were most discrepant (within- and between-individual explained variance of 0.90 and 0.46, respectively). ENMO, HFEN and HFEN+ explained 34%, 30% and 36% of the variance in daily PAEE, respectively, compared to 26% for a metric which did not attempt to remove the gravitational component (metric EN). CONCLUSION: In conclusion, none of the metrics as evaluated systematically outperformed all other metrics across a wide range of standardised kinematic conditions. However, choice of metric explains different degrees of variance in daily human physical activity

    A PUBLISH/SUBSCRIBE PROTOCOL FOR RESOURCE-AWARENESS IN WIRELESS SENSOR NETWORKS

    No full text
    Abstract Research has shown that alternating the routes in wireless sensor networks, can extend the network’s lifetime and increase communication savings. Many proposed data dissemination protocols, however, establish paths that guide data on a hop-level basis from sources to sinks. In this paper, we explain why such a tight-coupling (between the data dissemination and data routing) may be desired, even when a locationbased addressing scheme may be available; and describe a novel locationbased publish/subscribe protocol that offers support for the transparent operation of resource-aware routing protocols. Our protocol offers a trade-off between shared event dissemination paths (that can increase communication efficiency) and support for resource-awareness (that allows freedom of notification routing from the publishers to the subscribers)

    • Given

    No full text
    Mobile terminal location in indoor cellular multi-path environmen

    In silico comparative genome analysis of malaria parasite Plasmodium falciparum and Plasmodium vivax chromosome 4

    No full text
    Malarial parasite has long been a subject of research for a large community of scientists and has yet to be conquered. One of the main obstacles to effectively control this disease is rapidly evolving genetic structure of Plasmodium parasite itself. In this study, we focused on chromosome 4 of the Plasmodium falciparum and Plasmodium vivax species and carried out comparative studies of genes that are responsible for antigenic variation in respective species. Comparative analysis of genes responsible for antigenic variation (var and vir genes in P. falciparum and P. vivax, respectively) showed significant difference in their respective nucleotide sequence lengths as well as amino acid composition. The possible association of exon's length on pathogenecity of respective Plasmodium species was also investigated, and analysis of gene structure showed that on the whole, exon lengths in P. falciparum are larger compared to P. vivax. Analysis of tandem repeats across the genome has shown that the size of repetitive sequences has a direct effect on chromosomes length, which can also be a potential reason for P. falciparum's greater variability and hence pathogenecity than P. vivax
    corecore