1,796 research outputs found

    Underwater Optical Instrumentation

    Get PDF
    The paper presents a brief review of instrumentation necessary for carrying out in-situ light associated measurements in sea water. Recent developments in this area of instrumentation have been brought out. Practical significance of various parameters measured by these instruments has also been highlighted

    Flux jumps, Second Magnetization Peak anomaly and the Peak Effect phenomenon in single crystals of YNi2B2CYNi_2B_2C and LuNi2B2CLuNi_2B_2C

    Full text link
    We present magnetization measurements in single crystals of the tetragonal YNi2B2CYNi_2B_2C compound, which exhibit the phenomenon of peak effect as well as the second magnetization peak anomaly for H >> 0.5T (H || c). At the lower field (50mT << H << 200mT), we have observed the presence of flux jumps, which seem to relate to a structural change in the local symmetry of the flux line lattice (a first order re-orientation transition across a local field in some parts of the sample, in the range of 100mT to 150mT). These flux jumps are also observed in a single crystal of LuNi2B2CLuNi_2B_2C for H || c in the field region from 2 mT to 25 mT, which are compatible with the occurrence of a re-orientation transition at a lower field in a cleaner crystal of this compound, as compared to those of YNi2B2CYNi_2B_2C. Vortex phase diagrams drawn for H || c in LuNi2B2CLuNi_2B_2C and YNi2B2CYNi_2B_2C show that the ordered elastic glass phase spans a larger part of (H, T) space in the former as compared to latter, thereby, reaffirming the difference in the relative purity of the two samples.Comment: 11 pages, 14 figure

    Twist drill craniostomy vs Burr hole craniostomy in chronic subdural hematoma: A randomized study

    Get PDF
    Aim: To compare two most common operative procedures used in patients with chronic subdural hematomas - Twist drill craniostomy and Burr Hole Craniostomy.Material and Methods: The study was a prospective randomized controlled trial on patients with chronic subdural hematomas.Results: Both procedures are comparable with respect to outcome but surgical duration is statistically higher in Burr Hole craniostomy than Twist Drill Craniostomy.Conclusion: Twist Drill Craniostomy is procedure of choice in emergency surgical situation

    Antimicrobial susceptibility patterns of uropathogenic Escherichia coli and their prevalence among people in and around Dhanbad, Jharkhand

    Get PDF
    Background: Urinary tract infection (UTI) is one of the most common infections, which causes high morbidity and mortality among human population. The purpose of this study was to evaluate the prevalence and their antibiogram profile of uropathogenic Escherichia coli (UPEC) in and around Dhanbad. Methods: A total of 641 urine samples were collected from the suspected patients of UTI. The samples were cultured on MacConkey agar for isolation and identification. Antibiotic susceptibility test was done by disc diffusion method. Both male and female patients of different age groups were included for this study. Results: 45.70% urinary isolates were identified as E. coli. 43.56% UPEC isolates were sensitive to nitrofurantoin and piperacillin/tazobactum. 22.77% isolates were susceptible to levofloxacin and amikacin followed by cefotaxime (21.78%). These isolates were mostly resistant to ampicillin and trimethoprim/sulfamethoxazole, their susceptibility pattern was found to be 11.88% and 5.94% respectively. Conclusion: Prevalence of E. coli among urinary isolates was high in our study. Antibiogram profile of these isolates varies to different antibiotics in terms of their susceptibility pattern. Continuous surveillance of antibiogram of UPEC isolate is mandatory because it vary significantly in different geographical area. Thus empirical selection of antimicrobials should be based on the knowledge of local prevalence and individual sensitivity rather than on universal guideline

    Near-infrared Observations of Be/X-ray Binary Pulsar A0535+262

    Full text link
    We present results obtained from an extensive near-infrared spectroscopic and photometric observations of the Be/X-ray binary A0535+262/HDE 245770 at different phases of its ~111 day orbital period. This observation campaign is a part of the monitoring programme of selective Be/X-ray binary systems aimed at understanding the X-ray and near-IR properties at different orbital phases, especially during the periastron passage of the neutron star. The near-IR observations were carried out using the 1.2 m telescope at Mt. Abu IR observatory. Though the source was relatively faint for spectroscopic observations with 1.2 m telescope, we monitored the source during the 2011 February--March giant outburst to primarily investigate whether any drastic changes in the near-IR JHK spectra take place at the periastron passage. Changes of such a striking nature were expected to be detectable in our spectra. Photometric observations of the Be star show a gradual and systematic fading in the JHK light curves since the onset of the X-ray outburst that could suggest a mild evacuation/truncation of the circumstellar disc of the Be companion. Near-IR spectroscopy of the object shows that the JHK spectra are dominated by the emission lines of hydrogen Brackett and Paschen series and HeI lines at 1.0830, 1.7002 and 2.0585 micron. The presence of all hydrogen emission lines in the JHK spectra, along with the absence of any significant change in the continuum of the Be companion during X-ray quiescent and X-ray outburst phases suggest that the near-IR line emitting regions of the disc are not significantly affected during the X-ray outburst.Comment: 10 Pages, 5 Figures, Accepted for publication in Res. in Astronomy and Astrophysic

    Anisotropy in spatial order-disorder transformations and the vortex lattice symmetry transition in YNi2B2CYNi_2B_2C and LuNi2B2CLuNi_2B_2C

    Get PDF
    Explorations of the order-disorder transformation in vortex matter in single crystals of tetragonal structured (c/a \sim3) borocarbide superconductors, YNi2B2CYNi_2B_2C and LuNi2B2CLuNi_2B_2C, reveal that vortex arrays experience different effective pinning in different crystallographic directions. We surmise that correlation exists between the large anisotropy in effective pinning/disorder and the differences in the (local) symmetry transition from rhombohedral to (quasi) square vortex lattice(VL). For field along high symmetry directions, like, c-axis and ab-basal plane, the VL symmetry is close to square and the ordered state spans a large field interval. When the field is turned away from the c-axis towards ab-plane, at intermediate angles, the region of ordered state shrinks, in response to enhancement in effective pinning. At such intermediate angles the symmetry of the VL would be far from ideal triangular or square.Comment: 6 pages, 5 figures (Accepted in Euro Phys. Letts.

    Genetic dissection of grain weight in bread wheat through quantitative trait locus interval and association mapping

    Get PDF
    Genetic dissection of grain weight in bread wheat was undertaken through both genome-wide quantitative trait locus (QTL) interval mapping and association mapping. QTL interval mapping involved preparation of a framework linkage map consisting of 294 loci {194 simple sequence repeats (SSRs), 86 amplified fragment length polymorphisms (AFLPs) and 14 selective amplifications of microsatellite polymorphic loci (SAMPL)} using a bi-parental recombinant inbred line (RIL) mapping population derived from Rye Selection111 × Chinese Spring. Using the genotypic data and phenotypic data on grain weight (GW) of RILs collected over six environments, genome-wide single locus QTL analysis was conducted to identify main effect QTL. This led to identification of as many as ten QTL including four major QTL (three QTL were stable), each contributing >20% phenotypic variation (PV) for GW. The above study was supplemented with association mapping, which allowed identification of 11 new markers in the genomic regions that were not reported earlier to harbour any QTL for GW. It also allowed identification of closely linked markers for six known QTL, and validation of eight QTL reported earlier. The QTL identified through QTL interval mapping and association mapping may prove useful in marker-assisted selection (MAS) for the development of cultivars with high GW in bread whea

    Method of Identifying an Operating Regime in a Bubbling Fluidized Bed Gasification Reactor

    Full text link
    This work presents a new method for identifying the bubbling regime of a fluidized bed gasification reactor. The method has been developed using experimental measurements and a computational model. Pressure drops are measured in experiments, and pressure drop as well as solid volume fraction fluctuations are calculated by implementing the model. Experiments are carried out with sand and limestone particles of mean diameter 346 μm and 672 μm, respectively. A computational particle fluid dynamics (CPFD) model has been developed for the reactor and implemented using a commercial CPFD software Barracuda VR. The model is validated against experimental measurements. The validated model is used to analyse the fluctuation of pressure drop and solid volume fraction as a function of superficial air velocity. The change in standard deviation of pressure drop and solid volume fraction fluctuation is used to predict the transition from one regime to another. The method can be used in the design and operation of a bubbling fluidized bed gasification reactor. The results show that the minimum fluidization velocity for sand and limestone are 0.135 m/s and 0.36 m/s, respectively and are independent of the particle aspect ratio. Both types of particle beds make the transition into bubbling regime as soon as they get fluidized. The bed aspect ratios have almost no effect on the onset of bubbling f uidization regime. The slugging velocity decreases with increasing aspect ratio for both types of particles. The operating range of the bubbling fluidized bed for sand particle is 0.2–0.4 m/s and 0.5–0.8 m/s for the limestone particles
    corecore