Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea     

BASU Subhajit  MATONDKAR SG Prabhu  FURTADO Irene 《中国海洋湖沼学报》2013,31(1):10-20

In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca of NAS (20°N?17°N and 64°E–70°E), during the spring-inter-monsoon cruise of Sagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number (MPN) and plate counts, revealed ‘variable-physiotypes’ over a wide range of salinities (0%–25% w/v NaCl), pH levels (5–8.5), and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations *DWK and *PRB, corresponded to (3.08–4.41)×10³ cells/mL at 3.5% NaCl (w/v), and (2.82–9.49)×10² cells/mL at 25% (w/v) NaCl in tryptone-yeast extract broth (TYE). Plate counts were (1.12–4)×10⁶ CFU/mL at 0% (w/v) NaCl, (1.28–3.9)×10⁶ CFU/mL at 3.5% (w/v) NaCl, and (0.4–7)×10⁴ CFU/mL at 25% NaCl (w/v) on TYE. One-tenth-strength Zobell’s gave (0.6–3.74)×10⁵ CFU/mL at pH 5 to (3.58–7.5)×10⁵ CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Virgibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains (GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84) was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillus flexus, and Bacillus cereus. The ～2–3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.  相似文献   

Site-specific Probabilistic Seismic Hazard Map of Himachal Pradesh,India. Part I. Site-specific Ground Motion Relations     

Prabhu Muthuganeisan  S. T. G. Raghukanth 《Acta Geophysica》2016,64(2):336-361

This article presents four regional site-specific ground motion relations developed for the state of Himachal Pradesh in northwest Himalaya, situated in a seismically active region. These relations are developed from synthetic free surface ground motion databases obtained from a calibrated stochastic seismological model considering the characteristic properties of this specific region. The adopted methodology incorporates the site effects characterised through active MASW tests conducted in 22 important cities. The estimated ground motion levels from the developed relations are found to be in reasonable agreement with the recorded data.  相似文献   

Shoreline change along Kerala,south-west coast of India,using geo-spatial techniques and field measurement     

Selvan  S. Chenthamil  Kankara  R. S.  Prabhu  K.  Rajan  B. 《Natural Hazards》2020,100(1):17-38

Natural Hazards - Coastal zone is a central attraction for coastal engineers, scientists and coastal community due to economic and developmental activities of the coast. Kerala has 593 km...  相似文献   

Boundary-layer heights over the monsoon trough region during active and break phases     

G. R. Kusuma  Sethu Raman  A. Prabhu 《Boundary-Layer Meteorology》1991,57(1-2):129-138

The thermodynamic structure and the heights of the boundary layer over the monsoon trough region of the Indian southwest monsoon are presented for the active and break phases of the monsoon. Results indicate significant and consistent variation in boundary-layer heights between the active and break phases.  相似文献   

Photometric study of type Ia supernova SN 2002hu     

D. K. Sahu  G. C. Anupama  T. P. Prabhu 《Monthly notices of the Royal Astronomical Society》2006,366(2):682-688

Optical UBVRI photometry of the type Ia supernova (SN Ia) SN 2002hu covering the period from −2 to +73 d since B maximum is presented. The supernova reached at maximum brightness in B on  JD 245 2591.78 ± 0.5  with an apparent magnitude of  16.83 ± 0.02 mag  and a relatively blue colour  ( B − V ) =−0.08 ± 0.04 mag  . The luminosity decline rate of  Δ m ₁₅( B ) = 1.00 ± 0.05  indicates an absolute B magnitude at maximum of   M ^max _B =−19.38 ± 0.3  . The estimated absolute B magnitude, together with the photometric evolution, indicate SN 2002hu was slightly overluminous compared to the average SNe Ia. The distance modulus to the parent galaxy is estimated to be  μ= 36.04 ± 0.20  .  相似文献   

Wavelet Based Feature Extraction Techniques of Hyperspectral Data     

N. Prabhu  Manoj K. Arora  R. Balasubramanian 《Journal of the Indian Society of Remote Sensing》2016,44(3):373-384

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Post-outburst phase of McNeil's nebula (V1647 Orionis)     

D. K. Ojha  S. K. Ghosh  A. Tej  R. P. Verma  S. Vig  G. C. Anupama  D. K. Sahu  P. Parihar  B. C. Bhatt  T. P. Prabhu  G. Maheswar  H. C. Bhatt  B. G. Anandarao  V. Venkataraman 《Monthly notices of the Royal Astronomical Society》2006,368(2):825-836

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Distribution and seasonal variation of concentrations of particulate carbohydrates and uronic acids in the northern Indian Ocean   总被引：3，自引：0，他引：3  

Vishwas B. Khodse  Loreta Fernandes  V.V. Gopalkrishna  Narayan B. Bhosle  Veronica Fernandes  S.G. Prabhu Matondkar  Ravi Bhushan 《Marine Chemistry》2007,103(3-4):327-346

Suspended particulate matter (SPM) samples were collected from the surface seawaters at 31 stations, and from various depths (2 to 1000 m) at 9 locations in the northern Indian Ocean during various seasons. SPM samples were analyzed for total particulate carbohydrate (TPCHO), total particulate uronic acid (TPURA) and total particulate neutral carbohydrate (TPNCHO) concentrations and composition. Strong spatial, temporal and depth related variations were evident in the distribution of these compounds. In surface waters, concentrations of TPCHO, TPNCHO, and TPURA varied from 0.57 to 3.58 μM C, 0.11 to 2.34 μM C, and from 0.01 to 0.31 μM C, respectively, and accounted for 2.6 to 34.6%, 2 to 24.5%, and 0.2 to 6.3% of POC, respectively, whereas the TPURA accounted for 4.7 to 22.7% of TPCHO. Concentrations and yields of both TPNCHO and TPURA decreased rapidly in the upper 100 m of the water column suggesting their utilization by heterotrophic organisms. Glucose was the most abundant constituent of the TPNCHO. Glucose mole fraction decreased while that of other monosaccharides, especially galactose, arabinose, mannose, rhamnose and fucose increased in the upper 100 m water. Below this depth, mole fraction of glucose increased while that of other sugars decreased with the increasing water depth. Generally, high C:N ratios were associated with low yields of carbohydrates and uronic acids. Inverse correlation between the mole fractions of arabinose plus xylose and rhamnose plus fucose indicates the importance of biogenic and terrestrial organic matter input to the Bay of Bengal. TPURA are surface-active in nature and thus may play an important role in coagulation of particles and macromolecules. The observed spatial and seasonal variations of these compounds may be due to differences in phytoplankton biomass, nutrient status, and the influence of terrestrial material.  相似文献   

Site-specific Probabilistic Seismic Hazard Map of Himachal Pradesh,India. Part II. Hazard Estimation     

Prabhu Muthuganeisan  S. T. G. Raghukanth 《Acta Geophysica》2016,64(4):853-884

This article presents site-specific probable seismic hazard of the Himachal Pradesh province, situated in a seismically active region of northwest Himalaya, using the ground motion relations presented in a companion article. Seismic recurrence parameters for all the documented probable sources are established from an updated earthquake catalogue. The contour maps of probable spectral acceleration at 0, 0.2, and 1 s (5% damping) are presented for 475 and 2475 years return periods. Also, the hazard curves and uniform hazard response spectrums are presented for all the important cities in this province. Results indicate that the present codal provision underestimates the seismic hazard at cities of Bilaspur, Shimla, Hamirpur, Chamba, Mandi, and Solan. In addition, regions near Bilaspur and Chamba exhibit higher hazard levels than what is reported in literature.  相似文献   

Reconnaissance report on geotechnical effects and structural damage caused by the 3 January 2017 Tripura earthquake,India     

Anbazhagan  P.  Mog  Kunjari  Rao  K. S. Nanjunda  Prabhu  N. Siddharth  Agarwal  Ayush  Reddy  G. R.  Ghosh  Sima  Deb  Malay Kr.  Baruah  Saurabh  Das  Sarat Kr. 《Natural Hazards》2019,98(2):425-450

Natural Hazards - An earthquake of moment magnitude Mw 5.7 shook the northeastern region of India on 3 January 2017 at 14 h:39 min:0.5 s local time. The duration of the...  相似文献