the complexes of mn(oac)3 and/or mn(acac)3 with nucleic bases and nucleosides (adenine, guanine, xanthine, adenosine and guanosine) have been synthesized in nonaqueous solution. polarographic and spectroscopic (ir and visible) methods have been used to establish the active site(s) on the imidazole and pyrimidine rings in the nucleic bases and nucleosides for the interaction with the mn(iii) com...

The study of social networks has gained new importance with the recent rise of large on-line communities. Most current approaches focus on deterministic (descriptive) models and are usually restricted to a preset number of people. Moreover, the dynamic aspect is often treated as an addendum to the static model. Taking inspiration from real-life friendship formation patterns, we propose a new ge...

A new hypothetical mechanism is proposed for photoassembly of the (Mn)4-cluster of the photosynthetic oxygen evolving complex (OEC). In this process, a neutral radical of Y(Z) tyrosine plays a role in oxidizing Mn2+ associated with an apo-OEC, and also in abstracting a proton from a water molecule bound to the Mn2+ ion, together with D1-His190. This is in a similar fashion to the metallo-radica...

This paper introduces a new technique to model the excitation waveform for a linear predictive speech coder. The target application is high quality speech coding for rates near 4 kb/s. Our pitch pulse evolution model decomposes the excitation into two separate but simultaneous signals: the evolving pitch pulse component and the unvoiced, noise-like contribution. A number of formulations for dec...

It is well-known that Abstract State Machines (ASMs) can simulate “stepby-step” any type of machines (Turing machines, RAMs, etc.). We aim to overcome two facts: 1) simulation is not identification, 2) the ASMs simulating machines of some type do not constitute a natural class among all ASMs. We modify Gurevich’s notion of ASM to that of EMA (“Evolving MultiAlgebra”) by replacing the program (w...

Considerable concerns exist over privacy on social networks, and huge debates persist about how to extend the artifacts users need to effectively protect their rights to privacy. While many interesting ideas have been proposed, no single approach appears to be comprehensive enough to be the front runner. In this paper, we propose a comprehensive and novel reference conceptual model for privacy ...

This paper introduces a new technique to model the excitation waveform for a linear predictive speech coder The target appli cation is high quality speech coding for rates near kb s Our pitch pulse evolution model decomposes the excitation into two separate but simultaneous signals the evolving pitch pulse com ponent and the unvoiced noise like contribution A number of formulations for decompos...

Distributed learning in expert referral networks is a new Active Learning paradigm where experts—humans or automated agents—solve problems if they can or refer said problems to others with more appropriate expertise. Recent work augmented the basic learning-to-refer method with proactive skill posting, where experts may report their top skills to their colleagues, and proposed a modified algori...