3,425 research outputs found

    QUALITY BY DESIGN BASED DEVELOPMENT OF ETRAVIRINE SELF MICRO EMULSIFYING DRUG DELIVERY SYSTEM

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    Objective: The main objective of the present research work was to develop systematically the Self Micro Emulsifying Drug Delivery system of BCS Class IV drug in a Quality by Design framework. Methods: The quality by design-based formulation development proceeds with defining the Quality Target Product Profile and Critical Quality Attributes of dosage form with appropriate justification for the same. The statistical Mixture design was used for the development of the formulation. The independent variables selected for the design were Oleic acid, Labrasol and PEG 6000, whereas droplet size (nm), emulsification time (sec), % drug loading and % drug release at 15 min were considered as the potential quality attributes of the Self Micro Emulsifying System. The eight different batches of Etravirine-Self Micro Emulsifying systems (ETV-SMEDDS) were prepared and checked for the Critical Quality Attributes. The simultaneous optimization of the formulation was done by the global desirability approach. Results: The characterization report obtained for all the different batches of formulation was analyzed statistically by fitting into regression models. The statistically significant models determined for droplet size (nm) (R2= 0.96 and p-0.1022), emulsification time (sec) (R2= 0.99 and p-0.0267), % drug loading (R2= 0.93 and p-0.1667) and % drug release at 15 min (R2= 0.96 and p-0.0911) and were statistically significant. The maximal global desirability value obtained was 0.9415 and the value indicates, the selected factors and responses have a good correlation and are significant enough for optimization and prediction of best formulation. Conclusion: The QbD approach utilized during the development of ETV-SMEEDS facilitated the identification of Critical Material Attributes and their significant impact on the Critical Quality Attributes of SMEDDS. The concept of building quality into product through the QbD application was utilized successfully in the formulation development

    Establishment of Kerala Agricultural University Campus Wide Information System and Network: Feasibility Report

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    A Feasibility Report prepared by Centre for Agricultural Informatics in 1995 on establishing a Campus Network for Kerala Agricultural University’s (KAU) main campus (at Vellanikkara, Thrissur) and a state-of-the art Electronic Data Complex in its University Library premises. For the dissemination of topical awareness and global information to those in agricultural sector of the State, KAU needs to build a Campus LAN and state-of-the art Agricultural Digital Library and Data Complex within its central library. This can become a show case of the electronic age in agriculture and allied disciplines and will promote, propagate and catalogue the agricultural economy that India is so dependent on. The data complex will be a cached repository of agricultural information available worldwide, besides acting as a data silo for research forums, concurrent research, electronic publishing and global bulletin boards. The scattered campuses of KAU and allied institutions also need to be linked through electronic bridges that enable spontaneous exchange of information between the agricultural Diaspora of students, faculties, researchers, extension workers and administrators. The report covers mandate of the proposed system, detailed discussion on computer and communication stack that KAU Campus Wide Information System and Network needs, the architecture prescription, network design, MultiStack and DEChub 900 options available, host environment, financial terms, implementation methodology, installation support continuum, network synthesis and integration, systems engineering support, time frames and the administrative arrangements required. Open Network, with Protocol Switching and Networked Systems Management based on Digital's enVISN Networking Architecture and Enterprise Management Solutions is recommended. Detailed Technical literature and specifications of each and every item of computer and communication stack and solution recommended is appended to the report. Even though the report was prepared in 1995 it can be of interest for critical studies on history of ICT development in India especially in agricultural sector and for comparison of quality of systems and recommendations of a specific time in the past

    The eigenspectra of Indian musical drums

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    In a family of drums used in the Indian subcontinent, the circular drum head is made of material of non-uniform density. Remarkably, and in contrast to a circular membrane of uniform density, the low eigenmodes of the non-uniform membrane are harmonic. In this work we model the drum head by a non-uniform membrane whose density varies smoothly between two prescribed values. Using a Fourier-Chebyshev spectral collocation method we obtain the eigenmodes and eigenvalues of the drum head. For a suitable choice of parameters, which we find by optimising a cost function, the eigenspectra obtained from our model are in excellent agreement with experimental values. Our model and the numerical method should find application in numerical sound synthesis

    The Determination Of K ISCC Of Mild Steel In Hot Caustic By Using Small Circumferential Notched Tensile (CNT) Fracture Toughness Specimens

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    A new technique for rapid and cost-effective determination of stress intensity factor (K I) and fracture toughness (K IC) using small circumferential notch tensile (CNT) specimens is presented and used to determine the crack growth rate of an ex-service component. The paper highlights the scope and advantages of extending this technique for assessing the susceptibility of ferrous alloys to stress corrosion cracking (SCC). A modified CNT testing rig is designed and constructed based on an existing room temperature sustained load crack testing rig by adding facilities for testing SCC susceptibility at different temperatures. The new testing rig simplifies and speeds up the testing procedure as well as provides considerable cost advantage over the conventional fracture mechanics techniques. The paper also presents results of the SCC tests carried out on mild steel (AISI 1020) using this modified CNT rig

    Metal based pharmacologically active agents: Synthesis, structural elucidation, DNA interaction, in vitro antimicrobial and in vitro cytotoxic screening of copper(II) and zinc(II) complexes derived from amino acid based pyrazolone derivatives

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    AbstractThe paper presents the synthesis of complex combinations of Cu(II) and Zn(II) with Schiff base obtained by the condensation reaction of 4-aminoantipyrine with benzaldehyde and 2-amino-3-methyl-butanoicacid. Structural features of synthesized compounds were determined by analytical and spectral techniques. Binding of synthesized complexes with calf thymus DNA (CT DNA) was studied by spectroscopic methods and viscosity measurements. Experimental results indicated the ability of the complexes to form adducts with DNA and to distort the double helix by changing the base stacking. Oxidative DNA cleavage activities of the complexes were studied with supercoiled (SC) pUC19 DNA using gel electrophoresis. The in vitro antimicrobial screening effects of the investigated compounds were monitored by the disk diffusion method. The synthesized Schiff base complexes exhibited higher antimicrobial activity than the respective free Schiff base. The in vitro cytotoxicity of synthesized complexes against Ehrlich ascites carcinoma (EAC) tumor model was investigated using trypan blue dye exclusion assay. The complexes possessed significant cytotoxic activity

    Persistent currents of noninteracting electrons

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    We thoroughly study the persistent current of noninteracting electrons in one, two, and three dimensional thin rings. We find that the results for noninteracting electrons are more relevant for individual mesoscopic rings than hitherto appreciated. The current is averaged over all configurations of the disorder, whose amount is varied from zero up to the diffusive limit, keeping the product of the Fermi wave number and the ring's circumference constant. Results are given as functions of disorder and aspect ratios of the ring. The magnitude of the disorder-averaged current may be larger than the root-mean-square fluctuations of the current from sample to sample even when the mean free path is smaller, but not too small, than the circumference of the ring. Then a measurement of the persistent current of a typical sample will be dominated by the magnitude of the disorder averaged current.Comment: 10 pages, 4 figure

    Thermal oxidation of Ti6Al4V alloy: Microstructural and electrochemical characterization

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    Thermal oxidation (TO) of Ti6Al4V alloy was performed at 500, 650 and 800 ◦C for 8, 16, 24 and 48 h in air. The morphological features, structural characteristics, microhardness and corrosion resistance in Ringer’s solution of TO Ti6Al4V alloy were evaluated and compared with those of the untreated one. The surface morphological features reveal that the oxide film formed on Ti6Al4V alloy is adherent to the substrate at 500 and 650 ◦C irrespective of the oxidation time whereas it spalls off when the alloy is oxidized at 800◦C for more than 8 h. X-ray diffraction (XRD) measurement reveals the presence of Ti(O) and -Ti phases on alloy oxidized at 500 and 650◦C, with Ti(O) as the dominant phase at 650◦C whereas the alloy oxidized at 800◦C exhibits only the rutile phase. Almost a threefold increase in hardness is observed for the alloy oxidized at 650 ◦C for 48 h when compared to that of the untreated one. Thermally oxidized Ti6Al4V alloy offers excellent corrosion resistance in Ringer’s solution when compared to that of the untreated alloy

    Numerical simulation of the sensitivity of summer monsoon circulation and rainfall over india to land surface processes

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    The influence of soil moisture and vegetation variation on simulation of monsoon circulation and rainfall is investigated. For this purpose a simple land surface parameterization scheme is incorporated in a three-dimensional regional high resolution nested grid atmospheric model. Based on the land surface parameterization scheme, latent heat and sensible heat fluxes are explicitly estimated over the entire domain of the model. Two sensitivity studies are conducted; one with bare dry soil conditions (no latent heat flux from land surface) and the other with realistic representation of the land surface parameters such as soil moisture, vegetation cover and landuse patterns in the numerical simulation. The sensitivity of main monsoon features such as Somali jet, monsoon trough and tropical easterly jet to land surface processes are discussed. Results suggest the necessity of including a detailed land surface parameterization in the realistic short-range weather numerical predictions. An enhanced short-range prediction of hydrological cycle including precipitation was produced by the model, with land surface processes parameterized. This parameterization appears to simulate all the main circulation features associated with the summer monsoon in a realistic manner

    Experimental observation of the Bogoliubov transformation for a Bose-Einstein condensed gas

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    Phonons with wavevector q/q/\hbar were optically imprinted into a Bose-Einstein condensate. Their momentum distribution was analyzed using Bragg spectroscopy with a high momentum transfer. The wavefunction of the phonons was shown to be a superposition of +q and -q free particle momentum states, in agreement with the Bogoliubov quasiparticle picture.Comment: 4 pages, 3 figures, please take postscript version for the best version of Fig
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