X. Cheng

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This paper presents a summary of some of the work-in-progress within the Alexandria Digital Library Project. In particular, we present scalable methods of locating information at diierent levels within a distributed digital library environment. Starting at the high level, we show how queries can be routed to appropriate information sources. At a given(More)
Immune responses to persistent viral infections and cancer often fail because of intense regulation of antigen-specific T cells-a process referred to as immune exhaustion. The mechanisms that underlie the induction of exhaustion are not completely understood. To gain novel insights into this process, we simultaneously examined the dynamics of virus-specific(More)
Sensor networks are characterized by strict resource limitations and large scalability. Many sensor network applications require secure communication, a crucial component, especially in harsh environments. Symmetric key cryptography is very attractive in sensor networks due to its efficiency, but establishing a shared key for communicating parties is very(More)
PD-1, a receptor expressed by T cells, B cells, and monocytes, is a potent regulator of immune responses and a promising therapeutic target. The structure and interactions of human PD-1 are, however, incompletely characterized. We present the solution nuclear magnetic resonance (NMR)-based structure of the human PD-1 extracellular region and detailed(More)
Osteoclasts are specialised bone resorbing cells which form by fusion of circulating mononuclear phagocyte precursors. Bone resorption results in the release of large amounts of calcium into the extracellular fluid (ECF), but it is not certain whether changes in extracellular calcium concentration [Ca2+]e influence osteoclast formation and resorption. In(More)
The dynamics of magnetic reversal process plays an important role in the design of the magnetic recording devices in the long time scale limit. In addition to long time scale, microscopic effects such as the entropic effect become important in magnetic nano-scale systems. Many advanced simulation methods have been developed, but few have the ability to(More)