13,072 research outputs found

    Influence of exogenous urea on photosynthetic pigments, 14CO2 uptake, and urease activity in Elodea densa-environmental implications

    Full text link
    This paper analyzes the effect of exogenous urea in increased concentration gradient (0, 100, 500 and 1,000 mg L-1) on photosynthetic pigments (measured spectrophotometrically), uptake of 14CO2 (using radioisotope), and urease activity (by measuring ammonia with Nessler's reagent) in leaves of Elodea densa Planch. We have observed that low concentration of urea (100 mg L-1) stimulates the accumulation of photosynthetic pigments and intensifies photosynthesis in E. densa, whereas high concentration (1,000 mg L-1) suppresses these processes. Urease activity increased by approximately 2.7 and 8 fold when exogenous urea concentrations were 100 and 500 mg L-1, respectively. However, exogenous urea in high concentration (1,000 mg L-1) decreased urease activity by 1.5 fold compared to the control. The necessity of mitigating urea and other nitrogen-containing compounds (NH3 from urea) in water bodies has been discussed with emphasis on the potential for phytoremediation of urea using common water weed viz. E. densa. © 2013 Springer-Verlag Berlin Heidelberg

    Instability of Rotationally Tuned Dipolar Bose-Einstein Condensates

    Get PDF
    The possibility of effectively inverting the sign of the dipole-dipole interaction, by fast rotation of the dipole polarization, is examined within a harmonically trapped dipolar Bose-Einstein condensate. Our analysis is based on the stationary states in the Thomas-Fermi limit, in the corotating frame, as well as direct numerical simulations in the Thomas-Fermi regime, explicitly accounting for the rotating polarization. The condensate is found to be inherently unstable due to the dynamical instability of collective modes. This ultimately prevents the realization of robust and long-lived rotationally tuned states. Our findings have major implications for experimentally accessing this regime.Comment: 9 pages with 5 figure

    Content-Split Block Search Algorithm Based High Efficiency Video Coding

    Get PDF
    690-693In this paper, the video streaming generation in H.265 using novel technique based on content split block (CSB) search algorithm is presented. The proposed algorithm exploits the Inter and Intra prediction through motion estimation and compensation (IPME) encoded to use four different QPs: 22, 27, 32, and 37, during the redundancy analysis in order to improve the quality of video frame encoded. The proposed algorithm exhibits the useful property of block structure based on content-tree representation for each and every frame to IPME coded without affecting either the bit rate of video stream and perceptual quality of the video frame. The proposed Search algorithm improves the visual quality of coded video frame and reduces the blocking artefacts of video frame passed through multi-stages of H.265

    Evolution of faster development does not lead to greater fluctuating asymmetry of sternopleural bristle number in Drosophila

    Get PDF
    Both strong directional selection and faster development are thought to destabilize development, giving rise to greater fluctuating asymmetry (FA), although there is no strong empirical evidence supporting this assertion. We compared FA in sternopleural bristle number in four populations ofDrosophila melanogaster successfully selected for faster development from egg to adult, and in four control populations. The fraction of perfectly symmetric individuals was higher in the selected populations, whereas the FA levels did not differ significantly between selected and control populations, clearly indicating that directional selection for faster development has not led to increased FA in sternopleural bristle number in these populations. This may be because: (i) development time and FA are uncorrelated, (ii) faster development does result in FA, but selection has favoured developmentally stable individuals that can develop fast and still be symmetrical, or (iii) the increased fraction of symmetric individuals in the selected populations is an artifact of reduced body size. Although we cannot discriminate among these explanations, our results suggest that the relationship between development time, FA and fitness may be far more subtle than often thought

    Reduced larval feeding rate is a strong evolutionary correlate of rapid development in Drosophila melanogaster

    Get PDF
    This article does not have an abstract

    Can one hear the shape of the Universe?

    Get PDF
    It is shown that the recent observations of NASA's explorer mission "Wilkinson Microwave Anisotropy Probe" (WMAP) hint that our Universe may possess a non-trivial topology. As an example we discuss the Picard space which is stretched out into an infinitely long horn but with finite volume.Comment: 4 page

    Edge Computing and Blockchain in Smart Agriculture Systems

    Get PDF
    The advancement of Internet-based technologies has made huge progress toward improving the accessibility of "smart agriculture." With the advent of unmanned and automatic management, smart agriculture is now able to accomplish monitoring, supervision, and real-time picture monitoring. It is not possible to know for sure that the data in a smart agriculture system is complete and secure from intrusion. This article investigates and assesses the potential of edge computing and blockchain for use in smart agriculture. We combine the advantages of blockchain technology and the edge computing framework to create a smart agriculture framework system that is based on a very straightforward analysis of the evolution of smart agriculture. The study proposes a thorough method for emphasizing the significance of agriculture and edge computing, as well as the advantages of incorporating blockchain technology in this context. This paper also proposes an intelligent agricultural product traceability system design: edge computing with blockchain for smart agriculture. The study concludes with a discussion of outstanding problems and difficulties that can arise during the creation of a blockchain-based edge computing system for smart agriculture systems
    corecore