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Your search keyword '"KRISHNA MOORTHY, K"' showing total 190 results
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190 results on '"KRISHNA MOORTHY, K"'

14. Response of Ambient BC Concentration Across the Indian Region to the Nation-Wide Lockdown: Results from the ARFINET Measurements of ISRO-GBP

Author

Gogoi, Mukunda M., primary, Suresh Babu, S., additional, Arun, B. S., additional, Krishna Moorthy, K., additional, Ajay, A., additional, Ajay, P., additional, Suryavanshi, Arun, additional, Borgohain, Arup, additional, Guha, Anirban, additional, Shaikh, Atiba, additional, Pathak, Binita, additional, Gharai, Biswadip, additional, Ramasamy, Boopathy, additional, Balakrishnaiah, G., additional, Menon, Harilal B., additional, Kuniyal, Jagdish Chandra, additional, Krishnan, Jayabala, additional, Rama Gopal, K., additional, Maheswari, M., additional, Naja, Manish, additional, Kaur, Parminder, additional, Bhuyan, Pradip K., additional, Gupta, Pratima, additional, Singh, Prayagraj, additional, Srivastava, Priyanka, additional, Singh, R. S., additional, Kumar, Ranjit, additional, Rastogi, Shantanu, additional, Kundu, Shyam Sundar, additional, Kompalli, Sobhan Kumar, additional, Panda, Subhasmita, additional, Rao, Tandule Chakradhar, additional, Das, Trupti, additional, and Kant, Yogesh, additional

Published
2021
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20. Radiative Transfer Simulations for the Observed Decrease of Radio Brightness Temperature of Venus With Increasing Decimeter Wavelengths: Possible Existence of a Reflective or Quasi‐Conductive Subsurface.

Author

Antony, Tinu, Suresh Raju, C., Mohan, Nithin, Swarup, Govind, Oberoi, Divya, and Krishna Moorthy, K.

Subjects
RADIATIVE transfer, DECIMETER waves, PERMITTIVITY, HEAT radiation & absorption, RADIO telescopes
Abstract

Radiometric observations of Venus have revealed a monotonic decrease of brightness temperature (Tb) in the decimeter wavelength regime. Such a decrease has also been independently reported by the observations using interferometric radio‐telescopes, like the Very Large Array (VLA) in the USA and the Giant Metrewave Radio Telescope (GMRT) in India. In this work, we have carried out microwave radiative transfer (RT) simulations of thermal emission from the Venusian surface at decimeter wavelengths to examine the role of subsurface properties of Venusian regolith in the continuous reduction of Tb at the microwave‐radiowave spectral domain. These simulations are compared against spectral microwave measurements by GMRT over a wide decimeter wavelength regime ranging from ∼23–128 cm. Good agreements are obtained for simulations that consider a two‐layer Venusian surface (a low‐loss medium overlaid over a reflecting/lossy medium) a situation that would arise if the subsurface layer has high dielectric properties due to the presence of semiconducting mineral assemblages such as pyrites, ferroelectric minerals, magnetite–hematite, magnetite–pyrite or magnetite–hematite–pyrite equilibrium assemblages. The thickness of the top layer, the possibilities of the formation of such layers and their geological and chemical evolutions are also discussed. Plain Language Summary: Millimeter to decimeter radiometry measures thermal emission emanating from the planetary atmosphere, surface and subsurface. Radiometric observations of Venus showed a peculiar trend in the spectral variation of thermal emission (brightness temperature ‐Tb), which increases up to a wavelength of ∼6 cm and then decreases with increasing wavelength. The increase in thermal emission at shorter wavelengths (mm to cm), primarily contributed by the atmosphere, is well understood. However, a satisfactory explanation for the reduction of emission at the longer wavelengths in the decimeter regime is still lacking. We have provided an explanation to this problem by using radiative transfer (RT) simulations and Tb observations of Venus at decimeter wavelengths using the Giant Metrewave Radio Telescope (GMRT) located in Pune, India. Our studies suggest that Venus has a two‐layer surface structure with a low loss basaltic surface medium overlaid over a denser reflecting or semiconducting subsurface due to the presence of mineral assemblages, the rocks with iron‐rich mineralogical compounds formed by cooling and solidification of lava or magma. The evolution of the Venusian surface to the current state through volcanism, global resurfacing and related chemical weathering processes that support our argument are explained. Key Points: Investigated Venus' decreasing brightness with increasing decimeter wavelength using Radiative Transfer simulation and GMRT observationHypothesize possible existence of two‐layer surface, a layer of anhydrite‐basalt mixture overlaid on dense reflecting/conducting subsurfaceReflecting/conducting subsurface layer reduces Venus' Tb by reflecting back thermal radiations from deeper depths at decimeter wavelengths [ABSTRACT FROM AUTHOR]

Published
2022
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27. Relapse of leprosy presenting as nodular lymph node swelling

Author

Kiran K, Krishna Moorthy K, Meher Vani, and Rao P

Subjects
lcsh:Dermatology, Lymph node swelling, lcsh:RL1-803, relapse of leprosy
Abstract

Lymphadenopathy is known to be associated with lepromatous leprosy and has also been observed as a feature of type-2 lepra reaction. However, nodular lymph node enlargement is not commonly reported in leprosy patients or as a feature of relapse. We herewith are presenting a case of bacteriological relapse in a patient of lepromatous leprosy treated 22 years before till smear negativity with WHO multidrug therapy (MDT) multibacillary type (MB). She presented with prominent nodular swelling of the cervical group of lymph nodes along with generalized lymphadenopathy, which was mistakenly treated as tubercular lymphadenopathy. A diagnosis of late bacteriological relapse of lepromatous leprosy presenting with prominent lymphadenopathy and ENL was made after relevant investigations. The patient was started on treatment with WHO MDT MB (daily dapsone and clofazimine and monthly rifampicin) and thalidomide (200 mg/day). Nerve pain regressed within 2 weeks of therapy. The lymph nodal swelling regressed within 3 months of starting treatment.

Published
2009

28. Mycobacterial culture of fine needle aspirate - A useful tool in diagnosing tuberculous lymphadenitis

Author

Kishore Reddy V, Aparna S, Prasad C, Srinivas A, Triveni B, Gokhale S, and Krishna Moorthy K

Subjects
Extra pulmonary tuberculosis, fine needle aspiration, lcsh:QR1-502, lymph node tuberculosis, lcsh:Microbiology, culture
Abstract

A prospective study was undertaken on suspected lymph node TB (LNTB) patients, to evaluate the diagnostic utility of mycobacterial culture of fine needle aspirate (FNA), in comparison with the cytological examination and acid fast staining. Eighty percent of 157 aspirates studied were positive by cytological examination; 18% by ZN smear and 45% were positive by culture. Twelve aspirates which were negative by cytological features yielded positive mycobacterial cultures; four out of these were from HIV positive patients. Our observations suggest that supplementing FNA cytology with mycobacterial culture would increase the sensitivity of diagnosing LNTB; in addition to giving a highly specific diagnosis.

Published
2008

40. Heterogeneity in pre-monsoon aerosol types over the Arabian Sea deduced from ship-borne measurements of spectral AODs

Author

Kaskaoutis, D.G. Kalapureddy, M.C.R. Krishna Moorthy, K. Devara, P.C.S. Nastos, P.T. Kosmopoulos, P.G. Kambezidis, H.D.

Abstract

Ship-borne sunphotometer measurements obtained in the Arabian Sea (AS) in the pre-monsoon season (18 April-10 May 2006) during a cruise campaign (ICARB) have been used to retrieve the Aerosol Optical Depth (AOD; τ) and the Ångström wavelength exponent (α). The continents surrounding the AS produce natural and anthropogenic aerosols that have distinctive influences on α and its spectral distribution. The α values were estimated by means of the least-squares method over the spectral bands 340-1020 nm and 340-870 nm. The spectral distribution of AOD in logarithmic co-ordinates could be fit using a 2nd order polynomial with higher accuracy in the wavelength band 340-1020 nm than in the 340-870 nm band. A polynomial fit analytically parameterizes the observed wavelength dependencies of AOD with least errors in spectral variation of α and yields accurate estimates of the coefficients (α1 and α2). The coarse-mode (positive curvature in the ln λ vs. ln λ) aerosols are mainly depicted in the Northern part of the AS closely associated with the nearby arid areas while fine-mode aerosols are mainly observed over the far and coastal AS regions. In the study period the mean AOD at 500 nm is 0.25±0.11 and the α340-1020 is 0.90±0.19. The α340-870 exhibits similar values (0.92±0.18), while significant differences revealed for the constant terms of the polynomial fit (α1 and α2) proportionally to the wavelength band used for their determination. Observed day-to-day variability in the aerosol load and optical properties are direct consequence of the local winds and air-mass trajectories along with the position of the ship. © Author(s) 2010.

Published
2010

42. Maritime aerosol network as a component of AERONET – first results and comparison with global aerosol models and satellite retrievals

Author

Smirnov, A., Holben, B. N., Giles, D. M., Slutsker, I., O'Neill, N. T., Eck, T. F., Macke, A., Croot, Peter, Courcoux, Y., Sakerin, S. M., Smyth, T. J., Zielinski, T., Zibordi, G., Goes, J. I., Harvey, M. J., Quinn, P. K., Nelson, N. B., Radionov, V. F., Duarte, C. M., Losno, R., Sciare, J., Voss, K. J., Kinne, S., Nalli, N. R., Joseph, E., Krishna Moorthy, K., Covert, D. S., Gulev, S. K., Milinevsky, G., Larouche, P., Belanger, S., Horne, E., Chin, M., Remer, L. A., Kahn, R. A., Reid, J. S., Schulz, M., Heald, C. L., Zhang, J., Lapina, K., Kleidman, R. G., Griesfeller, J., Gaitley, B. J., Tan, Q., Diehl, T. L., Smirnov, A., Holben, B. N., Giles, D. M., Slutsker, I., O'Neill, N. T., Eck, T. F., Macke, A., Croot, Peter, Courcoux, Y., Sakerin, S. M., Smyth, T. J., Zielinski, T., Zibordi, G., Goes, J. I., Harvey, M. J., Quinn, P. K., Nelson, N. B., Radionov, V. F., Duarte, C. M., Losno, R., Sciare, J., Voss, K. J., Kinne, S., Nalli, N. R., Joseph, E., Krishna Moorthy, K., Covert, D. S., Gulev, S. K., Milinevsky, G., Larouche, P., Belanger, S., Horne, E., Chin, M., Remer, L. A., Kahn, R. A., Reid, J. S., Schulz, M., Heald, C. L., Zhang, J., Lapina, K., Kleidman, R. G., Griesfeller, J., Gaitley, B. J., Tan, Q., and Diehl, T. L.

Abstract

The Maritime Aerosol Network (MAN) has been collecting data over the oceans since November 2006. Over 80 cruises were completed through early 2010 with deployments continuing. Measurement areas included various parts of the Atlantic Ocean, the Northern and Southern Pacific Ocean, the South Indian Ocean, the Southern Ocean, the Arctic Ocean and inland seas. MAN deploys Microtops hand-held sunphotometers and utilizes a calibration procedure and data processing traceable to AERONET. Data collection included areas that previously had no aerosol optical depth (AOD) coverage at all, particularly vast areas of the Southern Ocean. The MAN data archive provides a valuable resource for aerosol studies in maritime environments. In the current paper we present results of AOD measurements over the oceans, and make a comparison with satellite AOD retrievals and model simulations.

Published
2011
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43. Maritime Aerosol Network as a component of Aerosol Robotic Network

Author

Smirnov, A., Holben, B.N., Slutsker, I., Giles, D.M., McClain, C.R., Eck, T.F., Sakerin, S.M., Macke, Andreas, Croot, Peter, Zibordi, G., Quinn, P.K., Sciare, J., Kinne, S., Harvey, M., Smyth, T.J., Piketh, S., Zielinski, T., Proshutinsky, A., Goes, J.L., Nelson, N.B., Larouche, P., Radionov, V.F., Goloub, P., Krishna Moorthy, K., Matarrese, R., Robertson, E.J., Jourdin, F., Smirnov, A., Holben, B.N., Slutsker, I., Giles, D.M., McClain, C.R., Eck, T.F., Sakerin, S.M., Macke, Andreas, Croot, Peter, Zibordi, G., Quinn, P.K., Sciare, J., Kinne, S., Harvey, M., Smyth, T.J., Piketh, S., Zielinski, T., Proshutinsky, A., Goes, J.L., Nelson, N.B., Larouche, P., Radionov, V.F., Goloub, P., Krishna Moorthy, K., Matarrese, R., Robertson, E.J., and Jourdin, F.

Abstract

The paper presents the current status of the Maritime Aerosol Network (MAN), which has been developed as a component of the Aerosol Robotic Network (AERONET). MAN deploys Microtops handheld Sun photometers and utilizes the calibration procedure and data processing (Version 2) traceable to AERONET. A web site dedicated to the MAN activity is described. A brief historical perspective is given to aerosol optical depth (AOD) measurements over the oceans. A short summary of the existing data, collected on board ships of opportunity during the NASA Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project is presented. Globally averaged oceanic aerosol optical depth (derived from island-based AERONET measurements) at 500 nm is similar to 0.11 and Angstrom parameter (computed within spectral range 440-870 nm) is calculated to be similar to 0.6. First results from the cruises contributing to the Maritime Aerosol Network are shown. MAN ship-based aerosol optical depth compares well to simultaneous island and near-coastal AERONET site AOD.

Published
2009
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