30 research outputs found
Temporal variations in <sup>87</sup>Sr/<sup>86</sup>Sr and ε<sub>Nd</sub> in sediments of the southeastern Arabian Sea: impact of monsoon and surface water circulation
Sr and Nd isotopic composition of silicate fractions of sediments have been measured in two well dated gravity cores from the eastern Arabian Sea archiving a depositional history of ∼29 and ∼40 ka. The 87Sr/86Sr and εNd in the northern core (SS-3104G; 12.8°N, 71.7°E) ranges from 0.71416 to 0.71840 and ā8.8 to ā12.8; these variations are limited compared to those in the southeastern core (SS-3101G; 6.0°N, 74.0°E), in which they vary from 0.71412 to 0.72069 and ā9.0 to ā15.2 respectively. This suggests that the variation in the relative proportions of sediments supplied from different sources to the core SS-3104G are limited compared to core SS-3101G. The 87Sr/86Sr and εNd profiles of SS-3101G exhibit two major excursions, ca. 9 ka and 20 ka, coinciding with periods of Holocene Intensified Monsoon Phase (IMP) and the Last Glacial Maximum (LGM) respectively with more radiogenic 87Sr/86Sr and lower εNd during these periods. These excursions have been explained in terms of changes in the erosion patterns in the source regions and surface circulation of the Northern Indian Ocean resulting from monsoon intensity variations. The intensification of North-East (NE) monsoon and associated strengthening of the East Indian Coastal Current in southwest direction during LGM transported sediments with higher 87Sr/86Sr and lower εNd from the western Bay of Bengal to the Arabian Sea. In contrast, enhanced South-West (SW) monsoon at ∼9 ka facilitated the transport of sediments from the northern Arabian Sea, particularly Indus derived, to the southeastern Arabian Sea. This study thus highlights the impact of monsoon variability on erosion patterns and ocean surface currents on the dispersal of sediments in determining the Sr and Nd isotopic composition of sediments deposited in the eastern Arabian Sea during the last ∼40 ka
Performance Evaluation of Workers in a Government Undertaking Company of India
Humans are having unlimited potential for growth and development which is measured in an organisation under Performance appraisal System (PAS). PAS is the process of analyzing and recording information about the relative worth of an employee, that is a two way communication process. It involves an active communication between employee and supervisor about performance. PAS can be measured by a system of evaluation but since there is no unanimous system exists the companies are using any one or their own system. Their system of PAS may be older one and sometime unable to measures the performance of the employees. Hence in this paper a company CCI is selected which has given the time and information to analyse their system and an improved system made by the researchers already were also used by taking a census survey of all employees of the company. To test the hypothesis independent sample t test was used with SPSS-19 software. It was found that the companyās current PA system has some hidden difficulties and the new system is able to measure the employees potential in well manner
Effects of Curcumin-loaded PLGA Nanoparticles in MDA-MB231 Human Breast Cancer Cells
Aim: This study was aimed at evaluating the anticancer potential of curcumin-loaded poly(lactic-co-glycolic acid) (PLGA) based nanoparticles (NPs) in MDA-MB231 human breast cancer cells. Methods: Curcumin-loaded PLGA NPs were developed using a modifiedĀ solvent evaporation technique. Physical characterization was performed on the formulated NPs. Furthermore, in vitro experiments were conducted to study the biological activity of the curcumin-loaded NPs. Results: Curcumin-loaded PLGA NPs demonstrated high encapsulation efficiency and sustained payload release. Moreover, the NPs exhibited a significant reduction in cell viability, cell migration and cell invasion in the MDA-MB231 cells. Conclusion: The study revealed that the formulated curcumin-loaded PLGA NPs possessed significant anti-metastatic properties. The findings showcased the possible potential of curcumin-loaded NPs in the management of debilitating conditions such as cancer. In addition, this study could form the basis for further research and advancements in this area. </jats:p
XBRL Acceptance in India: A Behavioral Study
XBRL is fast becoming the new paradigm for reporting of financial information digitally. XBRL brings structure to business information with comprehensive description and contextual information for advanced analysis. It enhances the efficiency of financial reporting, accuracy, timeliness and reliability of financial data. Many Indian companies still resist using it. The present research uses technology acceptance model to analyze the perception of financial experts in respect of acceptance of XBRL as reporting method. The result revealed that using XBRL increases productivity but interacting with the XBRL requires lot of mental efforts. These findings can be an empirical and theoretical foundation to accelerate the adoption of XBRL in India.
 
Impact of water mass mixing and dust deposition on Nd concentration and ε<sub>Nd</sub> of the Arabian Sea water column
The concentration and isotopic composition (εNd) of dissolved Nd have been measured in the sub-oxic/denitrifying water column of the eastern Arabian Sea to explore the impact of water mass mixing and release from particles. Dissolved Nd in the north-eastern Arabian Sea is more radiogenic (εNd: ā7 to ā10) compared to its south-eastern part (εNd: ā11 to ā15) suggesting contribution of Nd from the Bay of Bengal (BoB). The vertical profile of Nd typically show higher values in surface waters (15.8ā27.8 pmol/kg), followed by minima (12ā18 pmol/kg) in the subsurface waters (200ā300 m) and a gradual increase with depth thereafter. The Nd concentration does not seem to show any changes in the sub-oxic layers suggesting no impact of the sub-oxic/denitrifying conditions in this oceanic region on the biogeochemistry of Nd. The enrichment of Nd in surface waters can be explained either by supply from high Nd low salinity waters from the BoB to the Arabian Sea via the East India Coastal Current (EICC) or, alternatively the Nd surface excess can be result of release from aeolian dust depositing over the sea surface. Inverse modeling computations suggest that in addition to Nd contributed from water mass mixing, some additional excess Nd (Ndxs) is required to balance the Nd inventory in the water column. There is significant Ndxs in the surface waters of the north-eastern Arabian Sea with εNd ∼ ā6, similar to that of dust depositing over the Arabian Sea. The fractional solubility of Nd released from the aeolian dust was estimated to be varying from ∼3% to 17% (for excess Nd inventory per unit area (Ndxs*) of 20 μg mā2 with τNd ranging from 1 to 3 years). This study highlights the significance of aeolian dust deposition in controlling the abundance and distribution of Nd in the Arabian Sea, the western arm of the northern Indian Ocean, lying in the proximity to the arid landmass and characterized by high lithogenic aeolian dust deposition
Molybdenum isotopes in two Indian estuaries: mixing characteristics and input to oceans
The distributions of dissolved and particulate Mo and their isotope composition (δ<sup>98</sup>Mo) have been measured in the Narmada and the Tapi estuaries draining into the Arabian Sea. During monsoon, the δ<sup>98</sup>Mo of dissolved Mo in the Narmada estuary ranges from 0.49‰ to 2.19‰ in the salinity range 0ā17.2 practical salinity unit (psu) quite similar to that in the Tapi estuary, 0.99ā2.36‰, in the salinity range 0ā20.3 psu. Mo concentration in suspended sediments of the Narmada estuary collected during monsoon average 512 ± 44 ng/g (range 459ā602 ng/g) similar to that measured in one sample from the Tapi estuary 560 ng/g Mo. δ<sup>98</sup>Mo of particulate Mo in the Narmada ranges from ā0.21‰ to 0.48‰ with an average ā0.03 ± 0.2‰. Dissolved Mo in the Narmada and the Tapi rivers display isotopically heavier MĪæ compared to that in basalts, the major lithology of their drainage. This could result from a variety of processes, preferential weathering of Mo rich sulphide minerals dispersed in the basalts, preferential removal of isotopically lighter Mo during transport or contribution from marine cyclic salts supplied via rain or chemical weathering of organic rich shales in the basins.
The distribution of δ<sup>98</sup>Mo in the Narmada and the Tapi estuaries with salinity does not follow the theoretical mixing line between river and seawater endmembers suggesting its non-conservative behavior. Particulate Mo and δ<sup>98</sup>Mo show concomitant increase with salinity in the Narmada estuary indicating loss of dissolved Mo by adsorption onto FeāMn oxyhydroxide. Balancing the Mo budget along the course of these estuaries using inverse model suggests that in the Narmada estuary there could be loss up to 8% of the dissolved Mo and that in the Tapi supply from anthropogenic sources could be up to 27%. The results obtained in this study bring out the processes modifying riverine input of Mo and its Ī“98Mo in the estuaries, oxic sink in the Narmada and anthropogenic input in the Tapi. Repetitive adsorption and desorption of Mo in the Narmada estuary can modify the supply of dissolved Mo and its δ<sup>98</sup>Mo relative to riverine supply by up to 40%, this can significantly impact the Mo isotope budget of the oceans. In contrast, in the Tapi estuary there is enhancement in the dissolved supply of Mo relative to that from river due to anthropogenic input of Mo. The investigations in these two estuaries underscore the importance of solute particle interactions and anthropogenic input in determining the Mo flux and its δ<sup>98</sup>Mo to the open Arabian Sea
Spatial distribution of dissolved neodymium and ε<sub>Nd</sub> in the Bay of Bengal: role of particulate matter and mixing of water masses
The concentration and isotope composition of dissolved Nd have been measured in the water column along an 87°E transect (GIO1 section of International GEOTRACES Program) in the Bay of Bengal (BoB) to investigate the effect of water mass mixing and Nd release from particulate matter in determining these properties. The concentration of Nd in surface waters of the BoB shows a NorthāSouth decreasing non-linear trend (∼46 to ∼22 pmol/kg) with salinity, whereas its depth profiles typically show a high value in surface waters, a minimum (∼15 to ∼23 pmol/kg) in the shallow subsurface (∼50ā200 m), followed by a gradual increase with depth. The Nd concentration of BoB waters is generally higher than that in nearby oceanic basins. On the other hand, the εNd values in the BoB are less radiogenic compared to those reported for other regions of the global oceans (except Baffin Bay, the North Atlantic Subpolar Gyre and the Niger delta margin), and show a greater variation in the upper water column. Surface waters of the southernmost profile (∼6°N) show a more radiogenic ĪµNd value ∼ā8, which decreases to ā15 in the northernmost profile (∼20°N), close to the values for dissolved and particulate phases of the GangaāBrahmaputra (GāB) Rivers. This latitudinal trend is most likely a result of variations in mixing proportion between the more radiogenic Indonesian Throughflow surface waters (IW) and unradiogenic BoB low salinity water; the formerās signature being more clearly discernible in surface waters of the two southernmost profiles (∼6°N and ∼8.5°N). Attempts to balance the Nd budget in the water column based on an inversion model, suggest that in addition to water masses other source(s) is required, the strength of which is estimated to vary from 1% to 65% of the measured Nd concentration. The calculations also show that the ĪµNd of this additional source(s) has to be in the range of ∼ā16 ± 2, typical of GāB river sediments. These observations, coupled with the NorthāSouth distribution of dissolved Nd and ĪµNd, indicate that this additional source is release from particulate phases supplied by the GāB river system. The calculations also bring out the presence of āhot-spotsā of Nd release (excess Nd) near the sedimentāwater interface along the northern slope of the bay, indicating supply of Nd from continental margin sediments. This study underscores the significant role of dissolved/particulate Nd from the GangaāBrahmaputra river system in contributing to the dissolved Nd budget of the global oceans
Temporal variations in Sr and <sup>87</sup>Sr/<sup>86</sup>Sr of the Ganga headwaters: estimates of dissolved Sr flux to the mainstream
The headwaters of the Ganga (the Alaknanda, Bhagirathi and the Ganga) were analysed for their dissolved major ions, Sr and <sup>87</sup>Sr/<sup>86</sup>Sr on a biweekly to monthly basis over a period of one year to determine their temporal variations and the factors contributing to them. The concentrations of major ions and Sr show significant seasonal variation with lower values during monsoon period in all the three rivers. A similar trend is also observed for <sup>87</sup>Sr/<sup>86</sup>Sr and Na*/Ca (Na* = Na<sub>r</sub>-Cl<sub>r</sub>) suggesting relatively lower contribution of Sr and Na from silicates (which are more radiogenic in Sr) during monsoon. Budget calculations show that silicate derived dissolved Sr (Srs) in the river Ganga, Alaknanda and the Bhagirathi varied from 10 ± 4 to 27 ± 11, 7 ± 3 to 30 ± 12, 16 ± 6 to 57 ± 23% of measured Sr respectively with lower values during monsoon. The relative decrease in silicate erosion compared to carbonate during monsoon can result from several factors, these include higher dissolution kinetics of the carbonates, lower waterārock interaction time and availability of larger area for weathering. The annual discharge weighted Sr flux derived from the time series data is higher by ∼20% from that based on peak flow Sr, and lower by ∼40% compared to that derived from lean flow Sr concentration. The area-normalized annual flux of dissolved Sr from the Ganga at Rishikesh is about five times its flux at Rajshahi (Bangladesh) and a few other major global rivers, such as the Amazon, indicating higher erosion rate over the Himalaya