Birla Institute of Technology and Science

About: Birla Institute of Technology and Science is a education organization based out in Pilāni, Rajasthan, India. It is known for research contribution in the topics: Computer science & Population. The organization has 8897 authors who have published 13947 publications receiving 170008 citations.

Brimonidine Tartrate–Eudragit Long-Acting Nanoparticles: Formulation, Optimization, In Vitro and In Vivo Evaluation

Abstract: In the present study, an effort was made to design prolonged release Eudragit nanoparticles of brimonidine tartrate by double emulsion–solvent evaporation technique for the treatment of open-angle glaucoma. The effect of various formulation variables like initial drug amount, lecithin proportion, phase volume and pH, secondary emulsifier and polymer proportion were studied. Various process variables like energy and duration of emulsification, lyophilization on the characteristics of nanoparticles and in vitro drug release profile were studied. The selected formulations were subjected to in vivo intraocular pressure-lowering efficacy studies by administering aqueous dispersion of nanoparticles into the lower cul de sac of glaucomatous rabbits. The prepared Eudragit-based nanoparticles were found to have narrow particle size range and improved drug loading. The investigated process and formulation variables found to have significant effect on the particle size, drug loading and entrapment efficiency, and in vitro drug release profile of nanoparticles. The selected formulations upon in vivo ocular irritability and tolerability tests were found to be well tolerated with no signs of irritation. In vivo pharmacodynamic efficacy studies revealed that the selected nanoparticle formulations significantly improved the therapy as area under the ∆IOP vs. time curve [AUC(∆IOP vs.t)] showed several fold increase in intensity and duration of intraocular pressure (IOP) decrease. All the selected nanoparticle formulations were found to prolong the drug release in vitro and prolong IOP reduction efficacy in vivo, thus rendering them as a potential carrier in developing improved drug delivery systems for the treatment of glaucoma.

Bond strength and compressive stress-strain characteristics of brick masonry

Abstract: In this study, masonry and its material characteristics such as compressive strength of masonry prisms, bricks, mortars as well as bond strength (i.e., flexural and shear bond strengths) of brick and mortar joint are determined experimentally. The compressive stress-strain curves of brick, mortar, and masonry have been plotted and five control points have been identified on the stress-strain curve of masonry. The control points on the stress-strain curve would be useful for performance based design of masonry. Four types of bricks and three different types of mortars have been used in the experimental study. The compressive strength of masonry and flexural bond strength are determined with a test on five bricks stack bonded prisms. A bond wrench apparatus fabricated as per ASTM standards was used for flexural bond strength test. The shear bond strength of masonry is predicted using masonry triplet. It is observed that the concrete bricks have low flexural as well as shear bond strengths due to less contact area.

9-T SRAM Cell for Reliable Ultralow-Power Applications and Solving Multibit Soft-Error Issue

Abstract: Higher noise tolerance, lower power consumption, and higher reliability are the major design metrics for designing an SRAM cell. It is difficult to achieve an SRAM cell with stable operation at low voltage for low power consumption due to increasing variations in process, voltage, and temperature. It is proved that conventional 6 T fails to maintain its stability in scaled technology, particularly in deep-subthreshold regime. Furthermore, it does not support column bit-interleaving architecture. Therefore, it is very much prone to multibit soft error. In this paper, a double-ended read-decoupled ultralow-power 9-T SRAM cell (LP9T) is proposed, and the proposed cell supports the column bit-interleaving architecture. Because of read-decoupled technique, its noise tolerance is improved. To show the effectiveness of the proposed cell, it is compared with other recently published SRAM cells, namely, fully differential 8 T (FD8T), single-ended read-disturb-free 9 T (SEDF9T), and ultradynamic voltage scalable 10 T (UDVS10T). The proposed cell provides 1.2 $\times$ /2.3 $\times$ higher read current $I_{\mathrm{READ}}$ compared with UDVS10T/SEDF9T. Furthermore, LP9T shows 3.8 $\times$ /11.6 $\times$ improvement in read delay compared with FD8T/UDVS10T. The proposed cell achieves 3.9 $\times$ higher noise tolerance capability (i.e., read static noise margin (RSNM)) during read operation compared with FD8T. Moreover, LP9T consumes 2.1 $\times$ /2.1 $\times$ /4.9 $\times$ lower hold power $H_{\mathrm{Power}}$ during hold mode compared with FD8T/UDVS10T/SEDF9T. The proposed cell also exhibits 1.5 $\times$ /4.3 $\times$ /1.25 $\times$ narrower spread (i.e., more reliable) in $I_{\mathrm{READ}}/\text{RSNM}/H_{\mathrm{Power}}$ compared with UDVS10T/FD8T/SEDF9T. Furthermore, as the proposed cell supports bit-interleaving architecture, error checking and correction technique can be used to mitigate the issue related to multibit soft error. All these benefits are achieved by the LP9T at a cost of 1.17 $\times$ /1.17 $\times$ /1.25 $\times$ longer write delay compared with FD8T/UDVS10T/SEDF9T.