We study a fingerprinting game in which the number of colluders and the collusion channel are unknown. The encoder embeds fingerprints into a host sequence and provides the decoder with the capability to trace back pirated copies to the colluders.Fingerprinting capacity has recently been derived as the limit value of a sequence of maximin games with mutual information as their payoff functions. However, these games generally do not admit saddlepoint solutions and are very hard to solve numerically. Here under the so-called Boneh-Shaw marking assumption, we reformulate the capacity as the value of a single two-person zero-sum game, and show that it is achieved by a saddle-point solution.If the maximal coalition size is k and the fingerprinting alphabet is binary, we show that capacity decays quadratically with k. Furthermore, we prove rigorously that the asymptotic capacity is 1/(k 2 2 ln 2) and we confirm our earlier conjecture that Tardos' choice of the arcsine distribution asymptotically maximizes the mutual information payoff function while the interleaving attack minimizes it. Along with the asymptotics, numerical solutions to the game for small k are also presented.

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Developing new methods for chemotherapy drug delivery has become a topic of great concern. Vinca alkaloids are among the most widely used chemotherapy reagents for tumor therapy; however, their side effects are particularly problematic for many medical doctors. To reduce the toxicity and enhance the therapeutic efficiency of vinca alkaloids, many researchers have developed strategies such as using liposome-entrapped drugs, chemical- or peptide-modified drugs, polymeric packaging drugs, and chemotherapy drug combinations. This review mainly focuses on the development of a vinca alkaloid drug delivery system and the combination therapy. Five vinca alkaloids (eg, vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) are reviewed.

We study a fingerprinting game in which the collusion channel is unknown. The encoder embeds fingerprints into a host sequence and provides the decoder with the capability to trace back pirated copies to the colluders.Fingerprinting capacity has recently been derived as the limit value of a sequence of maxmin games with mutual information as the payoff function. However, these games generally do not admit saddle-point solutions and are very hard to solve numerically. Here under the so-called Boneh-Shaw marking assumption, we reformulate the capacity as the value of a single two-person zerosum game, and show that it is achieved by a saddle-point solution.If the maximal coalition size is k and the fingerprint alphabet is binary, we derive equations that can numerically solve the capacity game for arbitrary k. We also provide tight upper and lower bounds on the capacity. Finally, we discuss the asymptotic behavior of the fingerprinting game for large k and practical implementation issues.

The structures of snake venom metalloproteases (SVMPs) are proposed to be useful models to understand the structural and functional relationship of ADAM (a disintegrin and metalloprotease) which are membrane-anchored proteins involved in multiple human diseases. We have purified, sequenced and determined the structures of two new P-III SVMPs - atragin and kaouthiagin-like (K-like) from Naja atra. Atragin exhibits a known C-shaped topology, whereas K-like adopts an I-shaped conformation because of the distinct disulfide pattern in the disintegrin-like (D) domain. K-like exhibits an enzymatic specificity toward pro-TNFalpha with less inhibition of cell migration, but atragin shows the opposite effect. The specificity of the enzymatic activity is indicated to be dominated mainly by the local structures of SVMP in the metalloprotease (M) domain, whereas the hyper-variable region (HVR) in the cysteine-rich (C) domain is involved in a cell-migration activity. We demonstrate also a pH-dependent enzymatic activity of atragin that we correlate with the structural dynamics of a Zn(2+)-binding motif and the Met-turn based on the structures determined with a pH-jump method. The structural variations between the C- and I-shapes highlight the disulfide bond patterns in the D domain of the ADAM/adamalysin/reprolysins family proteins.

We study randomized fingerprinting codes that achieve the fundamental capacity limits subject to the so-called BonehShaw marking assumption. Two decoding schemes are studied in particular: the joint decoder is capacity-achieving but computationally intense, while the simple decoder is suboptimal but efficient. We provide tight bounds as well as numerical results for capacities and study the difference between these two schemes. Finally, security strategies for both the fingerprint embedders and the collusive attackers are presented.

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