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Santhosha D.,Sitha institute of pharmaceutical science Bachupally | Ramesh A.,Sitha institute of pharmaceutical science Bachupally | Kumar B.P.,Gurunanak Institute of pharmacy Ibrahimpatnam | Dhanalakshmi C.H.,HITS
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2011

Herbs play an important role in our day to day life. They were the only source of medicine in olden days. Even today herbs are equally important to modern drugs as they have fewer side effects when compared to synthetic drugs. Among so many herbs, this review exposed the information on vernacular names, microscopic, macroscopic, chemical constituents, uses and pharmacological actions on punarnava.


Aleksic J.,IFAE | Alvarez E.A.,Complutense University of Madrid | Antonelli L.A.,National institute for astrophysics | Antoranz P.,University of Siena | And 173 more authors.
Astronomy and Astrophysics | Year: 2012

We report on the detection of very-high energy (VHE, E > 100 GeV) γ-ray emission from NGC 1275, the central radio galaxy of the Perseus cluster of galaxies. The source has been detected by the MAGIC telescopes with a statistical significance of 6.6σ above 100 GeV in 46 h of stereo observations carried out between August 2010 and February 2011. The measured differential energy spectrum between 70 GeV and 500 GeV can be described by a power law with a steep spectral index of Γ =-4.1 ± 0.7 stat ± 0.3syst, and the average flux above 100 GeV is Fγ = (1.3 ± 0.2stat ± 0.3 syst) × 10-11 cm-2 s-1. These results, combined with the power-law spectrum measured in the first two years of observations by the Fermi-LAT above 100 MeV, with a spectral index of Γ ≈-2.1, strongly suggest the presence of a break or cut-off around tens of GeV in the NGC 1275 spectrum. The light curve of the source above 100 GeV does not show hints of variability on a month time scale. Finally, we report on the nondetection in the present data of the radio galaxy IC 310, previously discovered by the Fermi-LAT and MAGIC. The derived flux upper limit F U.L.γ (>300 GeV) = 1.2 × 10-12 cm-2 s-1 is a factor ∼ 3 lower than the mean flux measured by MAGIC between October 2009 and February 2010, thus confirming the year time-scale variability of the source at VHE. © 2012 ESO.


Aleksic J.,IFAE | Alvarez E.A.,Complutense University of Madrid | Antonelli L.A.,National institute for astrophysics | Antoranz P.,University of Siena | And 173 more authors.
Astronomy and Astrophysics | Year: 2012

Galaxy clusters are being assembled today in the most energetic phase of hierarchical structure formation which manifests itself in powerful shocks that contribute to a substantial energy density of cosmic rays (CRs). Hence, clusters are expected to be luminous gamma-ray emitters since they also act as energy reservoirs for additional CR sources, such as active galactic nuclei and supernova-driven galactic winds. To detect the gamma-ray emission from CR interactions with the ambient cluster gas, we conducted the deepest to date observational campaign targeting a galaxy cluster at very high-energy gamma-rays and observed the Perseus cluster with the MAGIC Cherenkov telescopes for a total of ∼85 h of effective observing time. This campaign resulted in the detection of the central radio galaxy NGC 1275 at energies E > 100 GeV with a very steep energy spectrum. Here, we restrict our analysis to energies E > 630 GeV and detect no significant gamma-ray excess. This constrains the average CR-to-thermal pressure ratio to be ≈ 1-2%, depending on assumptions and the model for CR emission. Comparing these gamma-ray upper limits to models inferred from cosmological cluster simulations that include CRs constrains the maximum CR acceleration efficiency at structure formation shocks to be <50%.Alternatively, this may argue for non-negligible CR transport processes such as CR streaming and diffusion into the outer cluster regions. Finally, we derive lower limits on the magnetic field distribution assuming that the Perseus radio mini-halo is generated by secondary electrons/positrons that are created in hadronic CR interactions: assuming a spectrum of E-2.2 around TeV energies as implied by cluster simulations, we limit the central magnetic field to be >4-9 μG, depending on the rate of decline of the magnetic field strength toward larger radii. This range is well below field strengths inferred from Faraday rotation measurements in cool cores. Hence, the hadronic model remains a plausible explanation of the Perseus radio mini-halo. © 2012 ESO.


Aleksic J.,IFAE | Antonelli L.A.,National institute for astrophysics | Antoranz P.,University of Siena | Backes M.,TU Dortmund | And 163 more authors.
Astrophysical Journal Letters | Year: 2010

We report on the detection with the MAGIC telescopes of very high energy (VHE) γ -rays from IC 310, a head-tail radio galaxy in the Perseus galaxy cluster, observed during the interval 2008 November to 2010 February. The Fermi satellite has also detected this galaxy. The source is detected by MAGIC at a high statistical significance of 7.6σ in 20.6 hr of stereo data. The observed spectral energy distribution is flat with a differential spectral index of -2.00 ± 0.14. The mean flux above 300 GeV, between 2009 October and 2010 February, (3.1 ± 0.5)×10-12 cm-2 s -1, corresponds to (2.5 ± 0.4)% of Crab Nebula units. Only an upper limit, of 1.9% ofCrab Nebula units above 300 GeV,was obtained with the 2008 data. This, together with strong hints (>3σ) of flares in themiddle of 2009 October and November, implies that the emission is variable. TheMAGIC results favor a scenario with the VHE emission originating from the inner jet close to the central engine. More complicated models than a simple one-zone synchrotron self-Compton (SSC) scenario, e.g., multi-zone SSC, external Compton, or hadronic, may be required to explain the very flat spectrum and its extension overmore than three orders ofmagnitude in energy. © 2010. The American Astronomical Society. All rights reserved.

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