62 research outputs found

    Determination of Heavy Metals Bioaccumulation in Two Green Leafy Vegetables by Atomic Absorption Spectroscopy

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    Two edible green leafy vegetables viz., Amaranthus (Amaranthus sp.) and Dill (Anethum graveolens) leaves collected randomly from three locations in Kolar district like Bethamangala, Bangarpet and K.G.F. are critically examined for heavy metal pollutants like Lead, Copper, Cadmium, Chromium and Zinc using Atomic Absorption Spectrophotometer. Results revealed that, Amaranthus and Dill leaves contain lead, copper, cadmium, chromium and zinc in all the sampling stations. Amaranthus leaves recorded significantly high lead concentration (41.57 ppm to 48.89 ppm) crossed permissible limits in all the stations. Copper concentration varied considerably in Bethamangala (4.26 ppm), Bangarpet (12.22 ppm) and KGF (21.59 ppm). Cadmium concentration at Bethamangala (2.06 ppm), Bangarpet (2.78 ppm) and KGF (2.96 ppm) recorded above permissible level. Chromium was detected in all the stations and values are not exceeding the permissible limit. Zinc concentration is higher in K.G.F (62.01 ppm) and in other two stations it is below the safe limit. Dill leaves showed high lead content (22.51 ppm-32.20 ppm) in three stations crossed safe value limit recommended by FAO/WHO. Copper concentration in Bethamangala (3.29 ppm), Bangarpet (12.22 ppm) and KGF (18.52 ppm) are in permissible limit. Cadmium content in Bethamangala (0.92 ppm) and Bangarpet (1.44 ppm) are below detection level and in KGF (2.32 ppm) exceeding the permissible limit. Chromium was detected in all three stations and values are below detection level. Zinc concentration is high in K.G.F (63.04 ppm) and in remaining two stations it is below the safe limit. Keywords: Heavy metals, leafy vegetables, amaranthus, dill, spectrophotometry

    Open data from the third observing run of LIGO, Virgo, KAGRA, and GEO

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    The global network of gravitational-wave observatories now includes five detectors, namely LIGO Hanford, LIGO Livingston, Virgo, KAGRA, and GEO 600. These detectors collected data during their third observing run, O3, composed of three phases: O3a starting in 2019 April and lasting six months, O3b starting in 2019 November and lasting five months, and O3GK starting in 2020 April and lasting two weeks. In this paper we describe these data and various other science products that can be freely accessed through the Gravitational Wave Open Science Center at https://gwosc.org. The main data set, consisting of the gravitational-wave strain time series that contains the astrophysical signals, is released together with supporting data useful for their analysis and documentation, tutorials, as well as analysis software packages

    Search for gravitational-wave transients associated with magnetar bursts in advanced LIGO and advanced Virgo data from the third observing run

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    Gravitational waves are expected to be produced from neutron star oscillations associated with magnetar giant f lares and short bursts. We present the results of a search for short-duration (milliseconds to seconds) and longduration (∼100 s) transient gravitational waves from 13 magnetar short bursts observed during Advanced LIGO, Advanced Virgo, and KAGRA’s third observation run. These 13 bursts come from two magnetars, SGR1935 +2154 and SwiftJ1818.0−1607. We also include three other electromagnetic burst events detected by FermiGBM which were identified as likely coming from one or more magnetars, but they have no association with a known magnetar. No magnetar giant flares were detected during the analysis period. We find no evidence of gravitational waves associated with any of these 16 bursts. We place upper limits on the rms of the integrated incident gravitational-wave strain that reach 3.6 × 10−²³ Hz at 100 Hz for the short-duration search and 1.1 ×10−²² Hz at 450 Hz for the long-duration search. For a ringdown signal at 1590 Hz targeted by the short-duration search the limit is set to 2.3 × 10−²² Hz. Using the estimated distance to each magnetar, we derive upper limits upper limits on the emitted gravitational-wave energy of 1.5 × 1044 erg (1.0 × 1044 erg) for SGR 1935+2154 and 9.4 × 10^43 erg (1.3 × 1044 erg) for Swift J1818.0−1607, for the short-duration (long-duration) search. Assuming isotropic emission of electromagnetic radiation of the burst fluences, we constrain the ratio of gravitational-wave energy to electromagnetic energy for bursts from SGR 1935+2154 with the available fluence information. The lowest of these ratios is 4.5 × 103

    A joint Fermi-GBM and Swift-BAT analysis of gravitational-wave candidates from the third gravitational-wave observing run

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    We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers

    Constraints on the cosmic expansion history from GWTC–3

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    We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding H0=688+12km  s1Mpc1{H}_{0}={68}_{-8}^{+12}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1} (68% credible interval) when combined with the H0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event's potential hosts. Assuming a fixed BBH population, we estimate a value of H0=686+8km  s1Mpc1{H}_{0}={68}_{-6}^{+8}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1} with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H0) is the well-localized event GW190814

    Off grid diesel engine-based trigeneration systems with thermal storage and compression chiller for enhanced performance

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    The paper proposes a diesel engine-based trigeneration system using a thermal storage for applications with simultaneous heating, cooling and power demand and where grid electricity is not available. A thermodynamic analysis is presented for the proposed trigeneration systems considering an 815 kWe diesel generator (DG) as a prime mover. Two configurations are considered. One configuration includes absorption chiller with an auxiliary hot water heater, while the other has a compression chiller in addition to the absorption chiller and water heater. Methodology of integrating a compression chiller is also presented. An analysis of both these options on primary energy savings basis for the considered DG shows that integrating a thermal storage and compression chiller enhances trigeneration performance. Without the compression chiller, the trigeneration system efficiency improves from 46% to 52% while with compression chiller integration, the improvement is much more from 46% to 72% when the power load decreases from 100% to 25%

    Efficacy of herbal toothpastes on salivary pH and salivary glucose – A preliminary study

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    Due to dearth of literature on the effect of herbal toothpaste on saliva and salivary constituents, the present study was undertaken to evaluate and compare the effect of three different herbal toothpastes with the focus on on salivary pH and salivary glucose. Forty five subjects in the age group of 19–21 years were randomly divided into 3 groups (15 in each group) and were randomly intervened with three different herbal toothpastes (Dant Kanti, Himalaya Complete Care and Vicco Vajradanti). Unstimulated saliva samples were collected before and after brushing and salivary glucose and pH levels were assessed at an interval of one week each for a period of 4 weeks starting from day 1. All the three toothpastes were effective in reducing the overall (p < 0.05) levels as well as levels of salivary glucose from pre-brushing to post-brushing at each interval (p < 0.05) and in increasing the overall levels as well as levels of salivary pH (p < 0.05) from pre-brushing to post-brushing at each interval. Herbal toothpastes were effective in reducing salivary levels of glucose and improving pH of the saliva
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