Indian Institute of Technology Bombay

About: Indian Institute of Technology Bombay is a education organization based out in Mumbai, India. It is known for research contribution in the topics: Population & Thin film. The organization has 16756 authors who have published 33588 publications receiving 570559 citations.

Multifunctional gold coated thermo-sensitive liposomes for multimodal imaging and photo-thermal therapy of breast cancer cells

Abstract: Plasmon resonant gold nanoparticles of various sizes and shapes have been extensively researched for their applications in imaging, drug delivery and photothermal therapy (PTT). However, their ability to degrade after performing the required function is essential for their application in healthcare. When combined with biodegradable liposomes, they appear to have better degradation capabilities. They degrade into smaller particles of around 5 nm that are eligible candidates for renal clearance. Distearoyl phosphatidyl choline : cholesterol (DSPC : CHOL, 8 : 2 wt%) liposomes have been synthesized and coated with gold by in situ reduction of chloro-auric acid. These particles of size 150–200 nm are analyzed for their stability, degradation capacity, model drug-release profile, biocompatibility and photothermal effects on cancer cells. It is observed that when these particles are subjected to low power continuous wave near infra-red (NIR) laser for more than 10 min, they degrade into small gold nanoparticles of size 5 nm. Also, the gold coated liposomes appear to have excellent biocompatibility and high efficiency to kill cancer cells through photothermal transduction. These novel materials are also useful in imaging using specific NIR dyes, thus exhibiting multifunctional properties for theranostics of cancer.

Efficient concurrency control for broadcast environments

Abstract: A crucial consideration in environments where data is broadcast to clients is the low bandwidth available for clients to communicate with servers. Advanced applications in such environments do need to read data that is mutually consistent as well as current. However, given the asymmetric communication capabilities and the needs of clients in mobile environments, traditional serializability-based approaches are too restrictive, unnecessary, and impractical. We thus propose the use of a weaker correctness criterion called update consistency and outline mechanisms based on this criterion that ensure (1) the mutual consistency of data maintained by the server and read by clients, and (2) the currency of data read by clients. Using these mechanisms, clients can obtain data that is current and mutually consistent “off the air”, i.e., without contacting the server to, say, obtain locks. Experimental results show a substantial reduction in response times as compared to existing (serializability-based) approaches. A further attractive feature of the approach is that if caching is possible at a client, weaker forms of currency can be obtained while still satisfying the mutual consistency of data.

Proxy-based acceleration of dynamically generated content on the world wide web: an approach and implementation

Abstract: As Internet traffic continues to grow and web sites become increasingly complex, performance and scalability are major issues for web sites. Web sites are increasingly relying on dynamic content generation applications to provide web site visitors with dynamic, interactive, and personalized experiences. However, dynamic content generation comes at a cost --- each request requires computation as well as communication across multiple components.To address these issues, various dynamic content caching approaches have been proposed. Proxy-based caching approaches store content at various locations outside the site infrastructure and can improve Web site performance by reducing content generation delays, firewall processing delays, and bandwidth requirements. However, existing proxy-based caching approaches either (a) cache at the page level, which does not guarantee that correct pages are served and provides very limited reusability, or (b) cache at the fragment level, which requires the use of pre-defined page layouts. To address these issues, several back end caching approaches have been proposed, including query result caching and fragment level caching. While back end approaches guarantee the correctness of results and offer the advantages of fine-grained caching, they neither address firewall delays nor reduce bandwidth requirements.In this paper, we present an approach and an implementation of a dynamic proxy caching technique which combines the benefits of both proxy-based and back end caching approaches, yet does not suffer from their above-mentioned limitations. Our dynamic proxy caching technique allows granular, proxy-based caching where both the content and layout can be dynamic. Our analysis of the performance of our approach indicates that it is capable of providing significant reductions in bandwidth. We have also deployed our proposed dynamic proxy caching technique at a major financial institution. The results of this implementation indicate that our technique is capable of providing order-of-magnitude reductions in bandwidth and response times in real-world dynamic Web applications.

Model-Based Object Tracking in Traffic Scenes

Abstract: This contribution addresses the problem of detection and tracking of moving vehicles in image sequences from traffic scenes recorded by a stationary camera. In order to exploit the a priori knowledge about the shape and the physical motion of vehicles in traffic scenes, a parameterized vehicle model is used for an intraframe matching process and a recursive estimator based on a motion model is used for motion estimation. The initial guess about the position and orientation for the models are computed with the help of a clustering approach of moving image features. Shadow edges of the models are taken into account in the matching process. This enables tracking of vehicles under complex illumination conditions and within a small effective field of view. Results on real world traffic scenes are presented and open problems are outlined.