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31.
The composition, species richness and diversity of a coastal fish assemblage from the Kalpakkam coast of south‐east India are described along with temporal distribution patterns related to seasonal fluctuations in dissolved oxygen, salinity, pH, chlorophyll‐a, phytoplankton and zooplankton species richness and density. A total of 244 fish species belonging to 21 orders, 87 families and 163 genera were recorded. The fish assemblage was dominated by reef‐associated species, followed by demersal species. The majority of the species (63%) are widely distributed in the western Indo‐Pacific as well as in the central Indo‐Pacific. Jaccard's coefficient analysis showed three distinct seasonal patterns of fish occurrence: pre‐monsoon (PrM), monsoon (M) and post‐monsoon (PoM). The maximum number of species was during the PrM period, followed by the PoM and M periods. Species occurrence analysis showed Sardinella longiceps to be dominant during PrM and M periods, Leiognathus dussumieri during the M period and Secutor insidiator and Secutor ruconius during the M and PoM periods. Canonical correspondence analysis indicated that salinity and rainfall were the two most influential environmental factors strongly correlated with temporal variation in the fish assemblage. The physico‐chemical conditions, in combination with factors such as greater food availability and shelter, might control the seasonal local distribution of the ichthyofauna in these Indian coastal waters.  相似文献   
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BackgroundThe importance of maternal sanitation behaviour during pregnancy for birth outcomes remains unclear. Poor sanitation practices can promote infection and induce stress during pregnancy and may contribute to adverse pregnancy outcomes (APOs). We aimed to assess whether poor sanitation practices were associated with increased risk of APOs such as preterm birth and low birth weight in a population-based study in rural India.ConclusionsThis study provides the first evidence, to our knowledge, that poor sanitation is associated with a higher risk of APOs. Additional studies are required to elucidate the socio-behavioural and/or biological basis of this association so that appropriate targeted interventions might be designed to support improved birth outcomes in vulnerable populations. While it is intuitive to expect that caste and poverty are associated with poor sanitation practice driving APOs, and we cannot rule out additional confounders, our results demonstrate that the association of poor sanitation practices (open defecation) with these outcomes is independent of poverty. Our results support the need to assess the mechanisms, both biological and behavioural, by which limited access to improved sanitation leads to APOs.  相似文献   
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An experiment was conducted to introduce the entomopathogen Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) as an endophyte in jute (Corchorus olitorius), a bast fibre crop through seed treatment. Colonization of root, leaf, stem, capsule, and seed were assessed through plating on selective medium and PCR based detection using B. bassiana specific SCAR markers. Endophytic colonization was detected in all the plants grown from treated seeds, but all the plant parts were not colonized. Colonization was detected in leaves, stems, and green capsules but not in roots and seeds. The endophytic colonization was influenced by both plant part and sampling period. Colonization was greater in leaves (55.87%) compared to stems (12.53%) and capsules (42.44%). The percent colonization was higher in case of 60?days old plants (43.34%) than in 30?days (23.89%) and 120?days (35.39%) old plants. As B. bassiana has already been reported to be pathogenic on jute pests, namely semilooper (Anomis sabulifera) and bihar hairy caterpillar (Spilosoma obliqua), its season long endophytic colonization within jute plant suggests a novel approach of biological control of these pests through seed treatment with the entomopathogen.  相似文献   
34.
In a previous report [Z. T?r?k, G. Satpathy, M. Banerjee, R. Bali, E. Little, R. Novaes, H. Van Ly, D. Dwyre, A. Kheirolomoom, F. Tablin, J.H. Crowe, N.M. Tsvetkova, Preservation of trehalose loaded red blood cells by lyophilization, Cell Preservation Technol. 3 (2005) 96-111.], we presented a method for preserving human red blood cells (RBCs) by loading them with trehalose and then freeze-drying. We have now improved that method, based on the discovery that addition of phospholipid vesicles to the lyophilization buffer substantially reduces hemolysis of freeze-dried RBCs after rehydration. The surviving cells synthesize 2,3-DPG, have low levels of methemoglobin, and have preserved morphology. Among the lipid species we studied, unsaturated PCs were found to be most effective in suppressing hemoglobin leakage. RBC-vesicle interactions depend on vesicle size and structure; unilamellar liposomes with average diameter of less than 300 nm were more effective in reducing the hemolysis than multilamellar vesicles. Trehalose loaded RBCs demonstrated high survival and low levels of methemoglobin during 10 weeks of storage at 4 degrees C in the dry state when lyophilized in the presence of liposomes.  相似文献   
35.
Cultivar variation in methane efflux from tropical rice   总被引:3,自引:0,他引:3  
Satpathy  S.N.  Mishra  S.  Adhya  T.K.  Ramakrishnan  B.  Rao  V.R.  Sethunathan  N. 《Plant and Soil》1998,202(2):223-229
Wide variation in CH4 flux was noticed among the ten rice cultivars grown under uniform field conditions. Cumulative CH4 flux ranged from 4.61 g m-2 to 20.25 g m-2. The rice cultivars could be ranked into three groups based on their CH4 flux potential. Rice cultivars could also be arranged based on their peak CH4 emission occurring either at vegetative, reproductive or at both growth stages. Of the several variables studied (root region redox potential, above- and underground biomass, grain and straw yield, duration of the crop, percent area occupied by the air space and root oxidase activity), only oxidase activity of the root tip exhibited a significant (negative) correlation with CH4 flux indicating an indirect effect of root oxidation potential on CH4 flux. Data presented in this study, demonstrate inherent variation in CH4 flux among different rice cultivars that can be used for developing future mitigation options.  相似文献   
36.
Kumaraswamy  S.  Ramakrishnan  B.  Satpathy  S.N.  Rath  A.K.  Misra  S.  Rao  V.R.  Sethunathan  N. 《Plant and Soil》1997,191(2):241-248
In a study on spatial distribution of methane oxidation in an unplanted flooded field, methane-oxidizing activity, analysed in soil samples under laboratory conditions, decreased with increasing depth (25 cm and beyond). In a flooded field planted to rice, rates of methane oxidation followed the order : rhizosphere (collected from roots at 10-20 cm depth) > surface soil at (0-1 cm) > subsurface soil at 10-20 cm depth, diagonally 10-15 cm away from the centre of hill. Application of ammonium sulfate and, to a lesser extent, urea to surface, rhizosphere and subsurface soil samples from flooded field planted to rice effected a distinct inhibition of methane oxidation. Nitrification inhibitors (thiourea, sodium thiosulfate and dicyandiamide) were also effective in inhibiting methane oxidation. Both surface and rhizosphere soil samples harbored higher populations of methane-oxidizing bacteria than the subsurface soil. Inhibition of methane oxidation in surface and rhizosphere soil samples concomitant with the suppression of autotrophic ammonium oxidizers by nitrification inhibitors implicates an active involvement of autotrophic ammonium oxidizers in methane oxidation.  相似文献   
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39.
Laboratory studies on adhesion of microalgae to hard substrates   总被引:1,自引:0,他引:1  
Sekar  R.  Venugopalan  V.P.  Satpathy  K.K.  Nair  K.V.K.  Rao  V.N.R. 《Hydrobiologia》2004,512(1-3):109-116
Adhesion of Chlorella vulgaris(chlorophyceae), Nitzschia amphibia(bacillariophceae) and Chroococcus minutus(cyanobacteria) to hydrophobic (perspex, titanium and stainless steel 316-L), hydrophilic (glass) and toxic (copper, aluminium brass and admiralty brass) substrata were studied in the laboratory. The influence of surface wettability, surface roughness, pH of the medium, culture age, culture density, cell viability and presence of organic and bacterial films on the adhesion of Nitzschia amphibia was also studied using titanium, stainless steel and glass surfaces. All three organisms attached more on titanium and stainless steel and less on copper and its alloys. The attachment varied significantly with respect to exposure time and different materials. The attachment was higher on rough surfaces when compared to smooth surfaces. Attachment was higher on pH 7 and above. The presence of organic film increased the attachment significantly when compared to control. The number of attached cells was found to be directly proportional to the culture density. Attachment by log phase cells was significantly higher when compared to stationary phase cells. Live cells attached more when compared to heat killed and formalin killed cells. Bacterial films of Pseudomonas putida increased the algal attachment significantly. %  相似文献   
40.
Reliable methods to quantify dynamic signaling changes across diverse pathways are needed to better understand the effects of disease and drug treatment in cells and tissues but are presently lacking. Here, we present SigPath, a targeted mass spectrometry (MS) assay that measures 284 phosphosites in 200 phosphoproteins of biological interest. SigPath probes a broad swath of signaling biology with high throughput and quantitative precision. We applied the assay to investigate changes in phospho‐signaling in drug‐treated cancer cell lines, breast cancer preclinical models, and human medulloblastoma tumors. In addition to validating previous findings, SigPath detected and quantified a large number of differentially regulated phosphosites newly associated with disease models and human tumors at baseline or with drug perturbation. Our results highlight the potential of SigPath to monitor phosphoproteomic signaling events and to nominate mechanistic hypotheses regarding oncogenesis, response, and resistance to therapy.  相似文献   
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