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"Hari, K. R"
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The mantle source of thermal plumes; trace and minor elements in olivine and major oxides of primitive liquids (and why the olivine compositions don't matter)
2018
We estimate the mantle source compositions for mantle plumes and, by implication, Earth's lower mantle by: (1) measuring trace (e.g, Sc, V, Cu) and minor (e.g., Ca, Mn, Ni) element concentrations of high-forsterite olivine grains from several plume localities, (2) estimating the parent liquid compositions from which they crystallized, (3) calculating mantle potential temperatures and degrees of partial melting, and (4) estimating trace element compositions of depleted and enriched mantle sources. Our sample set includes two continental flood basalt provinces (Emeishan and Deccan), a flood basalt that erupted in a continental rift setting (Baffin Island), our type example of a thermal mantle plume (Hawaii), and lavas from the Siqueiros Transform at the East Pacific Rise, which represent the mid-ocean ridge system. We also present olivine (Ol) compositions for peridotite xenoliths from Kilbourne Hole, New Mexico, U.S.A., which are commonly used as primary and secondary analytical standards. We find that trace elements in lava-hosted olivine grains are too far removed from their mantle source to provide anything but greatly hindered views of such. Olivine compositions reflect not only evolving liquid compositions (including partial melting conditions and later fractionation), but also evolving Ol+liq partition coefficients, which mostly increase with decreasing T during crystallization. Mantle compositions, delimited by maximum forsterite contents and estimates of parental magmas (and experimentally determined partition coefficients) indicate that our selected plumes reflect some combination of (1) a depleted mantle source that is quite similar to that obtained by other methods and (2) a variably enriched plume source that is more enriched than current estimates of pyrolite. The enriched plume mantle sources can be explained remarkably well as a mixture of subducted mid-ocean ridge basalt (MORB; Gale et al. 2013) and depleted MORB mantle (DM; Salters and Stracke 2004), with MORB:DMM ratios of 1:5 to 1:4. These ratios are most sensitive to estimates of melt fraction where plume parental magmas are last equilibrated with their mantle source, but are nonetheless consistent across a wide range of chemically very different elements, and estimates of MORB and DM obtained by very different means. Baffin Island is of particular interest. Like prior studies, we verify a high mantle potential temperature (Tp) of 1630 °C (compared to Tp = 1320-1420 °C for MORB from Cottrell and Kelley 2011 for Ol of Fo89.3-91.4). The Baffin source is also within error the same as DM with respect to trace elements, although still isotopically distinct; Baffin appears to be sourced in something that is akin to DMM that lies at the base of the mantle, where plumes acquire their excess heat. Thus while part of our analysis supports the concept of a \"slab graveyard\" at the bottom of the lower mantle (e.g., Wyession 1996), that cemetery is by no means ubiquitous at the CMB: subducted slabs are either unevenly interred, or efficiently excavated by later upwellings.
Journal Article
An In-vitro evaluation of a polyherbal formulation, against SARS-Cov-2
by
Venkatesh Hari, K.R.
,
Subramanian, Saumya
,
Pathania, Monika
in
antibiotic resistance
,
Antimicrobial agents
,
Ayurvedic
2022
In the last two years, COVID-19 pandemic caused by SARS-CoV-2 has created a mass destruction among humanity causing a major health crisis around the world. With the emergence of new strains of the virus, lack of targeted drugs and antimicrobial resistance, there is a dire need to discover specific antiviral with minimum side effects targeted against COVID-19.
The present study evaluates the antiviral efficacy of a novel Ayurvedic polyherbal formulation, NOQ19, composed of a 13 well known herbs, in a cell-based setting.
Vero E6 (CL1008), the African green monkey kidney epithelial cell, were infected with SARS-CoV-2 virus (isolate USA–WA1/2020) in a 96 well-plate. NOQ19 test material was diluted at different concentration: 0.05 mg/ml, 0.1 mg/ml, 0.2 mg/ml, 0.3 mg/ml, 0.4 mg/ml, 0.5 mg/ml, 0.6 mg/ml, 0.7 mg/ml, 0.8 mg/ml and 0.9 mg/ml. These different concentrations of NOQ19 were added to infected cells respectively and incubated for 3 days in 5% CO2 incubator. Remdesivir was used as a positive control. The cells were finally fixed with formaldehyde, stained with crystal violet and plaques were visualized. The number of plaques were counted to determine the PFU(plaque forming units)/ml.
The results of the present study demonstrated an excellent an antiviral efficacy of NOQ19 at 0.9 mg/ml concentration, eliminating 100% virus. The IC50 of the drug was found to be 0.2 mg/ml.
There is limited data around pre-clinical efficacy of polyherbal Ayurvedic drugs. Ayurvedic and herbal formations need to be tested in a preclinical setting to support the human data. The results of the present study demonstrated viral load reduction using NOQ19 in Vero E6 cell lines infected with SARS-CoV-2 virus. These result along with other preclinical and clinical trials could further evaluate the efficacy of NOQ19 as a potential therapeutic option in the fighting the COVID-19 challenge.
Journal Article
Mesozoic-Cenozoic extension of the Bohai Sea: contribution to the destruction of North China Craton
2014
The Bohai Sea is a Late Mesozoic-Cenozoic feature of the basin-mountain system located in eastern North China Craton (NCC). The Late Mesozoic thinning of the lithosphere signals the early destruction of the NCC. The onset of the destruction was due to the delamination of thick lithosphere of the craton, represented by the NW- trending grabens in an en-echelon arrangement west to Tanlu Fault, and by the NNE-trending grabens within the Tanlu Fault Zone. The Late Mesozoic NW-trending grabens are overprinted by structures related to the Cenozoic NE-trending pull-apart basin with very thick Mesozoic-Cenozoic sediments in the eastern NCC. C- frequency diagrams of growth faults and the extension factor (fl) of four sections across the basin suggest that the extension migrated from the margin to the center of Bohai Sea, and that the Mesozoic and Cenozoic extension factors for Bohai Sea are higher than that of the margin. These evidences suggest that the greatest extension occurred in the center of Bohai Sea, which is consistent with the thinnest crust being found in the center of the sea. The extension ratios and tectonic evolution of the Bohai Sea suggest that it is the key region for the destruction of the NCC, as evidenced by the topography. However, the NCC experienced two stages of destruction with the late stage related to the tectonic regime of Northeast Asia.
Journal Article
AI-driven framework to map the brain metabolome in three dimensions
by
Medina, Terrymar
,
Golamari, Hari K. R.
,
Vander Kooi, Craig W.
in
631/1647
,
631/1647/245/2160
,
631/378
2025
High-resolution spatial imaging is transforming our understanding of foundational biology. Spatial metabolomics is an emerging field that enables the dissection of the complex metabolic landscape and heterogeneity from a thin tissue section. Currently, spatial metabolism highlights the remarkable complexity in two-dimensional (2D) space and is poised to be extended into the three-dimensional (3D) world of biology. Here we introduce MetaVision3D, a pipeline driven by computer vision, a branch of artificial intelligence focusing on image workflow, for the transformation of serial 2D MALDI mass spectrometry imaging sections into a high-resolution 3D spatial metabolome. Our framework uses advanced algorithms for image registration, normalization and interpolation to enable the integration of serial 2D tissue sections, thereby generating a comprehensive 3D model of unique diverse metabolites across host tissues at submesoscale. As a proof of principle, MetaVision3D was utilized to generate the mouse brain 3D metabolome atlas of normal and diseased animals (available at
https://metavision3d.rc.ufl.edu
) as an interactive online database and web server to further advance brain metabolism and related research.
This study presents MetaVision3D, a pipeline to integrate mass spectrometry imaging sections into 3D reconstructions of metabolomic maps. The authors also provide a comprehensive 3D metabolome atlas of the brains of healthy mice and two disease models.
Journal Article
Sensitivity Analysis of Atmospheric Dispersion Simulations by FLEXPART to the WRF-Simulated Meteorological Predictions in a Coastal Environment
by
Baskaran, R.
,
Venkatraman, B.
,
Naidu, C. V.
in
Air pollution
,
Atmosphere
,
Atmospheric conditions
2016
In this study the sensitivity of the atmospheric dispersion model FLEXPART-WRF to the meteorological data inputs simulated by the mesoscale model ARW in the Kalpakkam coastal environment is examined. High-resolution simulations are conducted with ARW using four alternative planetary boundary layer parameterizations (YSU, MYNN, ACM2 and BL) for a typical period 14–22 Sep 2010 characterized with wide variability in atmospheric flow conditions at the coastal site. Observations generated through a field meteorological experiment are used to study the model sensitivity. Wind field, mixed layer depth, temperature and friction velocity are considered as parameters to evaluate dispersion uncertainty from FLEXPART. Results indicate that the simulated dispersion patterns are influenced by meteorological model forecasts using various boundary layer physics options. It has been found that the ensemble mean of all the meteorological members is closer to the observations than the individual cases. Of the various members the YSU and MYNN are found to give best meteorological simulations in the ensemble. The computed dispersion with various meteorological members indicate that ACM2 and BL simulate highest and least diffusivities leading to widely spread plume in the case of ACM2 and relatively narrow plume with BL, respectively. The ensemble mean of all the simulations is found to yield a better representation of the plume under various possible atmospheric conditions. The meteorological members YSU and MYNN are found to give minimum variance and fractional bias with respect to the ensemble. The minimum uncertainty in tracer concentration estimates due to meteorological uncertainty is −30 to 30 % obtained with MYNN. The results demonstrate that the dispersion model results are sensitive to the mesoscale model meteorological simulations.
Journal Article
Impact of period and timescale of FDDA analysis nudging on the numerical simulation of tropical cyclones in the Bay of Bengal
by
Ramakrishna, S. S. V. S.
,
Yesubabu, V.
,
Hari Prasad, K. B. R. R.
in
Assimilation
,
Bay of Bengal
,
Boundary conditions
2014
In this study, the impact of four-dimensional data assimilation (FDDA) analysis nudging is examined on the prediction of tropical cyclones (TC) in the Bay of Bengal to determine the optimum period and timescale of nudging. Six TCs (SIDR: November 13–16, 2007; NARGIS: April 29–May 02, 2008; NISHA: November 25–28, 2008; AILA: May 23–26, 2009; LAILA: May 18–21, 2010; JAL: November 04–07, 2010) were simulated with a doubly nested Weather Research and Forecasting (WRF) model with a horizontal resolution of 9 km in the inner domain. In the control run for each cyclone, the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) analysis and forecasts at 0.5° resolution are used for initial and boundary conditions. In the FDDA experiments available surface, upper air observations obtained from NCEP Atmospheric Data Project (ADP) data sets were used for assimilation after merging with the first guess through objective analysis procedure. Analysis nudging experiments with different nudging periods (6, 12, 18, and 24 h) indicated a period of 18 or 24 h of nudging during the pre-forecast stage provides maximum impact on simulations in terms of minimum track and intensity forecasts. To determine the optimum timescale of nudging, two cyclone cases (NARGIS: April 28–May 02, 2008; NISHA: November 25–28, 2008) were simulated varying the inverse timescales as 1.0e−4 to 5.0e−4 s
−1
in steps of 1.0e−4 s
−1
. A positive impact of assimilation is found on the simulated characteristics with a nudging coefficient of either 3.0e−4 or 4.0e−4 s
−1
which corresponds to a timescale of about 1 h for nudging dynamic (
u
,
v
) and thermodynamical (
t
,
q
) fields.
Journal Article
Geochemical constraints on the tectonic setting of the Sonakhan Greenstone Belt, Bastar Craton, Central India
by
M P Manu Prasanth
,
Deshmukh, S D
,
Hari, K R
in
Anomalies
,
Basalt
,
Computational fluid dynamics
2018
The Neo-Archean Sonakhan Greenstone Belt (SGB) located in the north-eastern fringes of Bastar craton, Central India, is dominated by Basalts, Andesites, Dacites and Rhyolites association. Partial melting modeling on the SGB metabasalts indicates that these rocks were derived by 20% melting of spinel peridotite. Fractional crystallisation modeling with REE reveal that the most evolved samples represent the product of fractional crystallization of least evolved magma with 35% plagioclase, 35% clinopyroxene, 20% olivine, 5% magnetite and 5% ilmenite as fractionating minerals with 40% remaining magma. Depletion of HFSE with reference to the LILE and LREE/HFSE ratios and Nb, Zr anomalies in the multi-element diagram of the mafic rocks of SGB indicate Island arc magmatic setting. The enriched Th/Yb values further substantiate that the mantle arrays were modified by subduction-related fluids or melts. The general conclusions drawn indicate that the metabasalts from the SGB were formed as a result of subduction of an intraoceanic lithosphere in a fore-arc suprasubduction zone environment.
Journal Article
Rate of Recovery and Symptomatic Efficacy of a Polyherbal AYUSH Formulation in the Treatment of SARS-CoV-2 Disease: A Single-arm Trial
by
Harsora, Prateek
,
Reddy, M Ravi Kumar
,
Subramanian, Saumya
in
Antiviral drugs
,
Asymptomatic
,
Ayurvedic medicine
2023
The COVID-19 pandemic, caused by the human coronavirus, SARS-CoV-2, has led to the death of millions across the globe. The SARS-CoV-2 virus is highly infectious, and mutates rapidly. This creates additional challenges for the development of robust therapeutic solutions. Along with modern healthcare, there is a need to explore natural, plant-based antiviral compounds that can be used in the treatment of COVID-19.
The present feasibility study investigates the efficacy of a 13-ingredient Ayurvedic polyherbal formulation, NOQ19, in the management of COVID-19.
A single-arm, open-label study design was adopted for this feasibility study. 161 RT-PCR-positive COVID-19 patients were enrolled. The enrolled participants were provided with the Ayurvedic intervention - two tablets of NOQ19 thrice daily along with the standard of care treatment. Follow-up COVID-19 RT-PCR tests were conducted on days 5, 10, and 14 or until the patient tested negative. The time taken to turn RT-PCR negative or become asymptomatic was noted.
The study was conducted at Sri Sri Institute for Advanced Research from April 2021 to June 2021.
A total of 161 COVID-19 patients isolating at home were assessed.
The NOQ19 preparation is a combination of 13 Ayurvedic herbs.
RT-PCR tests, the turnaround time to becoming asymptomatic, and regular symptoms assessment.
The analysis demonstrated that 74% of the patients tested negative on the RT-PCR within five days of taking NOQ19. Additionally, 98% of the subjects tested negative on the RT-PCR on day 10 after taking NOQ19 and standard of care treatment (as necessary). None of the participants reported any adverse events or side-effects due to NOQ19 medication.
The NOQ19 Ayurvedic polyherbal formulation can be an effective and safe option for the symptomatic management of COVID-19.
Journal Article
A Study on the Influence of the Land Surface Processes on the Southwest Monsoon Simulations using a Regional Climate Model
by
Bhaskar Rao, D. V.
,
Baskaran, R.
,
Venkatraman, B.
in
Air temperature
,
Albedo
,
Atmospheric circulation
2015
Influence of the land surface processes as an important mechanism in the development of the Indian Summer Monsoon is studied by performing simulations with a regional atmospheric model. Seasonal scale simulations are conducted for two contrasting summer monsoons (MJJAS months) in 2008 & 2009 with the Weather Research and Forecasting-Advanced Research regional model at a high resolution of 15 km using the boundary conditions derived from the National Centers for Environmental Prediction (NCEP) reanalysis data and using the NOAH land surface parameterization scheme. Simulations are evaluated by comparison of precipitation with 0.5° India Meteorological Department gridded rainfall data over land, atmospheric circulation fields with 1° resolution NCEP global final analysis, and surface fluxes with 0.75° resolution Era-Interim reanalysis. Results indicated significant variation in the evolution of the surface fluxes, air temperatures and flux convergence in the 2 contrasting years. A lower albedo, higher heating (sensible, latent heat fluxes), higher air temperatures, stronger flow and higher moisture flux convergence are noted over the subcontinent during the monsoon 2008 relative to the monsoon 2009. The simulated surface fluxes are in good comparison with observations. The stronger flow in 2008 is found to be associated with stronger heat flux gradients as well as stronger north-south geopotential/pressure gradients. The simulations revealed notable differences in many features such as zonal and meridional surface sensible heat gradients which, in turn, influenced the low-level pressure gradients, wind flow, and moisture transport. The present study reveals that, even at a regional scale, the physical processes of land-surface energy partitioning do influence the regional behavior of the monsoon system to a certain extent.
Journal Article
A vegetative storage protein improves drought tolerance in maize
by
Gupta, Rajeev
,
Loussaert, Dale F.
,
Howard, Richard J.
in
Amino acids
,
Bioaccumulation
,
biotechnology
2022
Summary Vegetative storage proteins (VSPs) are known to serve as nitrogen reserves in many dicot plants but remain undiscovered in grasses, most widely grown group of crops globally. We identified and characterized a VSP in maize and demonstrated that its overexpression improved drought tolerance. Nitrogen supplementation selectively induced a mesophyll lipoxygenase (ZmLOX6), which was targeted to chloroplasts by a novel N‐terminal transit peptide of 62 amino acids. When ectopically expressed under the control of various tissue‐specific promoters, it accumulated to a fivefold higher level upon expression in the mesophyll cells than the wild‐type plants. Constitutive expression or targeted expression specifically to the bundle sheath cells increased its accumulation by less than twofold. The overexpressed ZmLOX6 was remobilized from the leaves like other major proteins during grain development. Evaluated in the field over locations and years, transgenic hybrids overexpressing ZmLOX6 in the mesophyll cells significantly outyielded nontransgenic sibs under managed drought stress imposed at flowering. Additional storage of nitrogen as a VSP in maize leaves ameliorated the effect of drought on grain yield.
Journal Article