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Kumari, Beena
- Modelling of Plankton and Forage Fish Variability in the Gulf of Kachchh Using 2D Coupled Physico-Biological Model
Abstract Views :213 |
PDF Views:84
Authors
Affiliations
1 Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, IN
2 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, IN
1 Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, IN
2 Space Applications Centre, Indian Space Research Organisation, Ahmedabad 380 015, IN
Source
Current Science, Vol 113, No 06 (2017), Pagination: 1107-1119Abstract
A biophysical coupled model, which includes interaction of processes at different spatial and temporal scales, is used to assess the seasonal variability of plankton and forage fish. A five-compartment nutrient, phytoplankton, zooplankton, detritus, forage(NPZDF) ecological model is coupled with hydrodynamic model to understand the interaction of hydrographic characteristics and ecological dynamics in the study area. Operator splitting method is used to handle two different physical and biological scales for numerical simulation of the resulting partial differential equations. Gulf of Kachchh (22°20'N–23°40'N, 68°20'E–70°40'E), in the northwest coast of India is used for the application and validation of the model’s behaviour. This region demonstrates rich biodiversity and productivity in highly turbid and varying marine conditions. Co-ordinate transformation is used to convert the irregular coastal geometry of Gulf of Kachchh into a rectangular domain. Numerical experiments, together with sensitivity analysis are carried out to get the values/ranges of the model parameters. The model application is able to bring out many striking features of the Gulf of Kachchh including bimodal oscillations observed in the ecological data of the region.Keywords
Gulf of Kachchh, Physico-Biological Model, Plankton and Forage Fish.Full Text
References
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- Formulation and Characterization of Gastroretentive Floating Tablets of Atorvastatin Calcium Using Central Composite Design
Abstract Views :196 |
PDF Views:58
Authors
Affiliations
1 Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak – 124001, IN
1 Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak – 124001, IN
Source
Journal of Pharmaceutical Research, Vol 16, No 3 (2017), Pagination: 247-256Abstract
The aim of the study was to develop a gastroretentive floating drug delivery system of atorvastatin calcium by effervescence technique.
Design/methodology/approach: The objective behind the study was to investigate the effect of concentration of HPMC K4M (X), concentration of guar gum (X), concentration of sodium bicarbonate (X) on the release of 1 2 3 atorvastatin calcium using central composite design.The floating tablets were formulated using atorvastatin calcium (20% w/w), HPMC K4M (5-15% w/w), guar gum (5-15% w/w), sodium bicarbonate (4-12% w/w), lactose (q.s.), talc (2% w/w) and magnesium stearate (1% w/w). Atorvastatin calcium floating tablets were evaluated for physical characterization viz. hardness, swelling index, floating capacity, weight variation, friability, in vitro drug release and kinetic studies.
Findings: All tablets were floated for more than 12 hrs in 0.1 N HCl at 37±0.5°C and the in vitro drug release was found to be vary from 79% to 93%. The percentage cumulative drug released was maximum at low value of HPMC, low value of guar gum and high value of sodium bicarbonate. A mathematical model was developed to formulate floating tablets of atorvastatin calcium. The data fitting to Korsemeyer-Peppas equation revealed that the release mechanism from the dosage form followed the non-fickian transport.
Value: The gastroretentive floating tablets of atorvastatin calcium will enhance the patient compliance and play a vital role in improving patient's quality of life.
Keywords
Atorvastatin Calcium, Central Composite Design, In Vitro Drug Release, Floating Tablets.Full Text
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