531 research outputs found

    Morphometric analysis of population samples of soldier caste of Odontotermes obesus (Rambur) (Isoptera, Termitidae, Macrotermitinae)

    Get PDF
    In order to study morphometric variations in Odontotermes obesus (Rambur), samples from nineteen nests were statistically analyzed for mean, standard deviation, standard error, coefficient of variability and confidence interval (95%) and analysis of variance (Model II ANOVA), The mean values of the different population samples were compared with the student t-test, following the Minitab version and Sokal & Rohlf (1973). In the study of external characters, measurements form a very important component, particularly for identification of species. However, the reliability of the measurements depends on the extent of variability which the structures show within and between colonies. For each individual soldier, the following nine parameters were measured: i) length of head; ii) width of head at mandibles; iii) width of head at the posterolateral ends of antennal carinae; iv) maximum width of head; v) length of left mandible; vi) tooth of left mandible from tip; vii) length of pronotum; viii) width of pronotum; ix) length of postmentum; and x) width of postmentum

    Encapsulated virgin coconut oil as a nanoscale in vitro solution against multiple drug resistant Staphylococcus aureus

    Get PDF
    Abstract Niosomes are excellent nanoscale vehicular systems that can carry a variety of drugs and (bioactive) compounds entrapped inside them. Virgin coconut oil (VCO) is the finest grade of coconut oil that is highly enriched with phenolic content, antioxidant activity and also comprises medium chain triglycerides. In this work, niosomes were encapsulated with VCO synthesized by a simple chemical method. The electron microscopy confirmed that spherical nanostructured lipid carrier molecules with a diameter in the range of 180–190 nm were produced. A zeta potential value of −42 mV was a testimony that these nanovehicles were having good stability. The natural oil loaded nanocarrier spheres proved to be potent antibacterial nano‐antibiotics against multiple drug resistant (MDR) bacteria. The antibacterial activity of these magic nano‐spheres was found to be better than ZnO (metallic oxides) nanoparticles. The nano‐antibiotics resulted in 17, 14 and 12 mm zones of inhibition against methicillin‐resistant Staphylococcus aureus (MRSA), vancomycin‐resistant S. aureus (VRSA) and a (general) MDR strain of S. aureus in contrast to nanoparticles that resulted in zones of inhibitions 7, 8 and 6 mm for the same bacterial strains. Niosomes prove to be an excellent nanocarrier system that can encapsulate a number of bio‐active compounds

    Collisionless shock acceleration of narrow energy spread ion beams from mixed species plasmas using 1 μ\mum lasers

    Full text link
    Collisionless shock acceleration of protons and C6+^{6+} ions has been achieved by the interaction of a 1020^{20} W/cm2^2, 1 μ\mum laser with a near-critical density plasma. Ablation of the initially solid density target by a secondary laser allowed for systematic control of the plasma profile. This enabled the production of beams with peaked spectra with energies of 10-18 MeV/a.m.u. and energy spreads of 10-20%\% with up to 3x109^9 particles within these narrow spectral features. The narrow energy spread and similar velocity of ion species with different charge-to-mass ratio are consistent with acceleration by the moving potential of a shock wave. Particle-in-cell simulations show shock accelerated beams of protons and C6+^{6+} ions with energy distributions consistent with the experiments. Simulations further indicate the plasma profile determines the trade-off between the beam charge and energy and that with additional target optimization narrow energy spread beams exceeding 100 MeV/a.m.u. can be produced using the same laser conditions.Comment: Accepted for publication in Physical Review Accelerators and Beam

    Back-analysis of Preexisting Landslides

    Get PDF
    ABSTRACT Drained residual shear strength is applicable to slopes containing preexisting shear surfaces and preexisting landslides. Laboratory ring shear testing by various researchers suggest the possibility of strength gain along preexisting shear surfaces which had previously obtained a residual strength condition. This paper presents back-analysis of two case histories that were used to suggest strength recovery to confirm test results developed herein and explain how the recovered strength may be useful in understanding slope behavior during the rest period and movement reactivation. These back-analyses are important to determine whether or not strength gain occurs and the practical significance, if any, of the strength gain in design of the remedial measures

    Time variations in the deep underground muon flux measured by MACRO

    Full text link
    More than 30 million of high-energy muons collected with the MACRO detector at the underground Gran Sasso Laboratory have been used to search for flux variations of different natures. Two kinds of studies were carried out: search for periodic variations and for the occurrence of clusters of events. Different analysis methods, including Lomb-Scargle spectral analysis and Scan Test statistics have been applied to the data.Comment: 6 pages, 4 EPS figures. Talk given at the 29th ICRC, Pune, India, 3-10 August 200

    Thermal, electrochemical and mechanical properties of shape memory alloy developed by a conventional processing route

    Get PDF
    A Cu based shape memory alloy (Cu-Al-Ni) having a composition 83% Cu, 14% Al, 3% Ni, was developed and studied to determine the shape memory effect. Powder of Cu, Al and Ni was melted in a pit furnace at about 15500C, and casted alloy was heat treated at 8500C for a period of 50 minutes followed by water quenching. Microstructure characterization of alloy (Cu-Al-Ni) was carried out to determine the pre-quenched (cast structure) and quenched martensitic structure. The microstructure analysis of developed samples showed needle like structure of quenched martensite after heat treatment. It has a very good resemblance with structure of casted shape memory alloy obtained from the vacuum induction process. The Vickers hardness test was also performed. Quenched microstructure with improved hardness than pre-quenched structure was observed.Keywords: Shape Memory Alloy, Microstructure, Mechanical Propertie

    Data Warehouse Model to Support Optimized Operation and Energy Savings in Buildings

    Get PDF

    Search for massive rare particles with the SLIM experiment

    Full text link
    The search for magnetic monopoles in the cosmic radiation remains one of the main aims of non-accelerator particle astrophysics. Experiments at high altitude allow lower mass thresholds with respect to detectors at sea level or underground. The SLIM experiment is a large array of nuclear track detectors at the Chacaltaya High Altitude Laboratory (5290 m a.s.l.). The results from the analysis of 171 m2^2 exposed for more than 3.5 y are here reported. The completion of the analysis of the whole detector will allow to set the lowest flux upper limit for Magnetic Monopoles in the mass range 105^5 - 1012^{12} GeV. The experiment is also sensitive to SQM nuggets and Q-balls, which are possible Dark Matter candidates.Comment: Presented at the 29-th ICRC, Pune, India (2005
    corecore