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Article history: Received on: 19/02/2013 Revised on: 03/03/2013 Accepted on: 03/04/2013 Available online: 27/04/2013 The botany, traditional medicinal uses, phytochemistry, and pharmacology of S. torvum Sw. belonging to family Solanaceae have been reviewed by evaluating information on the Internet (using Google Scholar, CABAbstracts, Blackwell synergy, Elsevier, Cambridge University Press, JSTOR, Nature Publishing and Science online) and in libraries. Traditional medicinal uses of S. torvum were recorded in the Ayurveda and Chinese pharmacopeia. The present review study covered chemical constituents and pharmacological properties of S. torvum as well as its morphology. This has included therapeutic effects of the whole plant and its extracts, fractions and isolated compounds. Antimicrobial, anti-ulcerogenic, antiviral, anti-platelet aggregation, antioxidant, analgesic, anti-inflammatory, systolic blood-pressure modification, and cytotoxic activities have all been described. Previous research studies carried out using different in-vitro and in-vivo bioassay techniques supported the claims of the therapeutic utility of the species.

The formation timescale and final architecture of exoplanetary systems are closely related to the properties of the molecular disks from which they form. Observations of the spatial distribution and lifetime of the molecular gas at planet-forming radii (a < 10 AU) are important for understanding the formation and evolution of exoplanetary systems. Toward this end, we present the largest spectrally resolved survey of H2 emission around low-mass pre-main-sequence stars compiled to date. We use a combination of new and archival far-ultraviolet spectra from the Cosmic Origins Spectrograph and Space Telescope Imaging Spectrograph instruments on the Hubble Space Telescope to sample 34 T Tauri stars (27 actively accreting Classical T Tauri Stars and 7 non-accreting Weak-lined T Tauri Stars) with ages ranging from ~1 to 10 Myr. We observe fluorescent H2 emission, excited by Lyα photons, in 100% of the accreting sources, including all of the transitional disks in our sample (CS Cha, DM Tau, GM Aur, UX Tau A, LkCa 15, HD 135344B, and TW Hya). The spatial distribution of the emitting gas is inferred from spectrally resolved H2 line profiles. Some of the emitting gas is produced in outflowing material, but the majority of H2 emission appears to originate in a rotating disk. For the disk-dominated targets, the H2 emission originates predominately at a lesssim 3 AU. The emission line widths and inner molecular radii are found to be roughly consistent with those measured from mid-IR CO spectra.

[1] The Hankasalmi SuperDARN radar in Finland, while operating in a high spatial and temporal resolution mode, has measured the ionospheric signature of a naturally occurring ULF wave in scatter artificially induced by the Tromsø Heater. The wave had a period of 100 s and exhibited curved phase fronts across the heated volume (about 180 km along a single radar beam). Spatial information provided by the radar has enabled an m-number for the wave of about 38 to be determined. It is demonstrated here that the curved phase fronts are a generic feature of nonstationary poloidal waves in a transverse resonator, caused by the common action of the field line curvature, the plasma pressure, and the equilibrium current. Some features of the observed event agree with the resonator in the vicinity of the ring current, where it is proposed that the wave is excited by a moving source in the form of a proton cloud drifting in the magnetosphere in the azimuthal direction.

[1] We survey the Cassini magnetometer data during the deep tail orbits in 2006, and find 34 direct encounters with plasmoids. They occur as single, isolated events but also in groups of two or more plasmoids as is frequently observed at Earth. We show a case study example of three such plasmoids over three hours, where we estimate an upper limit of 5.68 GWb of flux closure, and derive a reconnection rate over this interval of 526 kV. We show the results of a superposed epoch analysis of all 34 plasmoids indicating that, on average, plasmoids at Saturn are ∼8 min in duration and they tend toward a loop-like, as opposed to flux rope-like topology, with little or no axial core magnetic field. Our analysis shows that plasmoids at Saturn are followed by an extended interval of the post-plasmoid plasma sheet (PPPS) lasting ∼58 min. The average open magnetic flux disconnected by the continued reconnection following plasmoid formation that creates the PPPS is ∼3 GWb. We calculate expected recurrence rates for plasmoids, and compare these with a derived observational recurrence rate of one plasmoid every ∼2.4 days, explaining the reasons why the spacecraft has not observed as many plasmoids as we predict will be released. We conclude that the Cassini magnetometer measurements require a combination of Vasyliunas-type closed-flux plasma sheet and Dungey-type open-flux lobe reconnection to account for the observed properties of the plasmoids and PPPS in Saturn's magnetotail.

[1] CloudSat observations have indicated that multiple scattering affects 94 GHz spaceborne radar observations. The ESA EarthCARE explorer mission scheduled to launch in 2015 features also a spaceborne 94-GHz radar with Doppler capability for providing a global data set of convective motions and particle sedimentation rates. Vertical velocity measurements will be collected in all cloud conditions, including deep convection where multiple-scattering is expected to contaminate the signal. Thus, before the spaceborne Doppler radars are used for science application, it is imperative to develop a method to identify radar range gates contaminated by multiple scattering contributions. Based on simulations, a criterion to identify the onset of multiple scattering is presented in this paper; the cumulative integrated reflectivity from the top of the atmosphere is a proxy of the multiple scattering enhancement and can be confidently used to detect the onset of multiple scattering. Analysis of a limited (two months) CloudSat data set reveals that, for deep tropical convective cores, the onset of significant multiple scattering typically occurs in the region between 9–10 km and more than 35% of the range bins above the freezing level height and with reflectivity above −20 dBZ are not affected by multiple scattering. This assessment offers a conservative upper limit for EarthCARE 94-GHz radar multiple scattering effects due to the narrower field of view of the Doppler radar compared to CloudSat's radar. Identification of multiple scattering contamination in the CloudSat and EarthCARE radar observations facilitates the following objectives: (1) to constrain the region of validity of currently developed CloudSat products based on single scattering theory (e.g. 2B-CWC-RO, 2B-CWC-RVOD) and (2) to filter out multiple scattering affected range bins in any analysis aimed at the assessment of the feasibility and of the accuracy of the EarthCARE Doppler estimates within deep convective cores.

Aim Elevated circulating endothelin-1 (ET-1) has been demonstrated in patients with colorectal cancer (CRC). The aim of this study was to examine the prognostic value of plasma big ET-1, the stable precursor of ET-1, in cancer-specific survival in patients having curative surgery for CRC. Method Seventy-seven patients undergoing potentially curative surgery for CRC between January 2000 and January 2001 were studied. Clinicopathological data were obtained from a prospectively maintained database including long-term follow-up information (median follow up 84 months). The influence of plasma big ET-1 and clinicopathological variables upon over cancer-specific survival was determined by univariate and multivariable analysis. Results On univariate analysis, advanced Dukes’ stage, tumour size and patient age were associated with shortened overall survival. Advanced Dukes’ stage was the only factor associated with shortened survival on multivariable analysis. Plasma big ET-1 showed no association with either overall or cancer-specific survival following CRC resection. Conclusion Plasma big ET-1 appears to have no prognostic value in primary CRC.

[1] It has recently been shown using Cassini radio data that Saturn kilometric radiation (SKR) emissions from the Northern and Southern hemispheres of Saturn are modulated at distinctly different periods, ∼10.6 h in the north and ∼10.8 h in the south, during the southern summer conditions that prevailed during the interval from 2004 to near-equinox in mid-2009. Here we examine Cassini magnetospheric magnetic field data over the same interval and show that two corresponding systems of magnetic field oscillations that have the same overall periods, as the corresponding SKR modulations, to within ∼0.01% are also present. Specifically, we show that the rotating quasi-dipolar field perturbations on southern open field lines and the rotating quasi-uniform field in the inner region of closed field lines have the same period as the southern SKR modulations, although with some intervals of slow long-term phase drift of unknown origin, while the rotating quasi-dipolar field perturbations on northern open field lines have the same period as the northern SKR modulations. We also show that while the equatorial quasi-uniform field and effective southern transverse dipole are directed down tail and toward dawn at southern SKR maxima, as found in previous studies, the corresponding northern transverse dipole is directed approximately opposite, pointing sunward and also slightly toward dawn at northern SKR maxima. We discuss these findings in terms of the presence of two independent high-latitude field-aligned current systems that rotate with different periods in the two hemispheres.

From a deep multi-epoch Chandra observation of the elliptical galaxy NGC 3379 we report the spectral properties of eight luminous LMXBs (LX> 1.2× 10 38 erg s -1 ). We also present a set of spectral simulations, produced to aid the interpretation of low-count single-component spectral modeling. These simulations demonstrate that it is possible to infer the spectral states of X-r ay binaries from these simple models and thereby constrain the properties of the source. Of the eight LMXBs studied, three reside within globular clusters, and one is a confirmed field source. Due to the nature of the luminosity cut all sources are either neu tron star binaries emitting at or above the Eddington luminosity or black hole binaries. The spectra from these sources are well described by single-component models, with parameters consistent with Galactic LMXB observations, where hard-state sources have a range

[1] While the Cluster spacecraft were located near the high-latitude magnetopause, between 1010 and 1040 UT on 16 January 2004, three typical flux transfer event (FTE) signatures were observed. During this interval, simultaneous and conjugated all-sky camera measurements, recorded at Yellow River Station, Svalbard, are available at 630.0 and 557.7 nm that show poleward-moving auroral forms (PMAFs), consistent with magnetic reconnection at the dayside magnetopause. Simultaneous FTEs seen at the magnetopause mainly move northward, but having duskward (eastward) and tailward velocity components, roughly consistent with the observed direction of motion of the PMAFs in all-sky images. Between the PMAFs meridional keograms, extracted from the all-sky images, show intervals of lower intensity aurora which migrate equatorward just before the PMAFs intensify. This is strong evidence for an equatorward eroding and poleward moving open-closed boundary associated with a variable magnetopause reconnection rate under variable IMF conditions. From the durations of the PMAFs, we infer that the evolution time of FTEs is 5–11 minutes from its origin on the magnetopause to its addition to the polar cap.