Fast computation of Bernoulli, Tangent and Secant numbers

We consider the computation of Bernoulli, Tangent (zag), and Secant (zig or Euler) numbers. In particular, we give asymptotically fast algorithms for computing the first n such numbers in O(n^2.(log n)^(2+o(1))) bit-operations. We also give very short in-place algorithms for computing the first n Tangent or Secant numbers in O(n^2) integer operations. These algorithms are extremely simple, and fast for moderate values of n. They are faster and use less space than the algorithms of Atkinson (for Tangent and Secant numbers) and Akiyama and Tanigawa (for Bernoulli numbers).Comment: 16 pages. To appear in Computational and Analytical Mathematics (associated with the May 2011 workshop in honour of Jonathan Borwein's 60th birthday). For further information, see http://maths.anu.edu.au/~brent/pub/pub242.htm

Forum Selection and Choice of Law Clauses in International Contracts: A United States Viewpoint with Particular Reference to Maritime Contracts and Bills of Lading

This Article approaches the topic of forum selection from a U.S. perspective. It is reasonable to expect, however, particularly with regard to bills of lading and maritime trade, that the approach of other nations toward international contracts is, or soon will be, very similar. For the sake of simplicity, choice of law and choice of forum will be addressed together, and referred to as either choice of forum or forum selection. Many contracts only specify a particular forum, while others specify only the application of a particular law. U.S. courts and international conventions have generally taken the same approach to both and, therefore, from the standpoint of legal recognition, they are virtually indistinguishable. This Article will outline the current state of the law govern- ing choice of law, choice of forum, and dispute resolution with respect to international contracts involving United States entities. Part II provides a brief overview of the general state of United States law with regard to forum selection provisions in international contracts. Part III focuses on contracts of maritime trade and the broad recognition currently accorded such contracts. It also includes a brief history of the developing recognition of forum selection clauses in bills of lading. Arbitration clauses have traditionally received different treatment from U.S. courts and therefore will be addressed separately in Part IV. In 1995, however, the distinction between forum selection and arbitration clauses was virtually eliminated by the Supreme Court when it recognized the full freedom of contracting parties to choose particular forms of dispute resolution

Trust and Persistence

We rely on computers to control our power plants and water supplies, our automobiles and transportation systems, and soon our economic and political systems. Increasingly, software agents are enmeshed in these systems, serving as the glue that connects distributed components. Clearly, we need mechanisms to determine whether these agents are trustworthy. What do we need to establish trust? Agents are often characterized by features such as autonomy, sociability, proactiveness, and persistent identity. This latter feature is key in determining trust. When agents operate over an extended period, they can earn a reputation for competence, timeliness, ease of use, and trustworthiness, which is something ephemeral agents cannot do. Along with persistence, we need a reliable way to identify an agent and ensure that its true identity is not concealed. How can we assess an agent\u27s trustworthiness? As with other aspects of agents and multiagent systems, we can take our cue from the human domain. Our reputations for trustworthiness are determined and maintained by the people we deal with. Analogously, a software agent\u27s reputation will reside within the other agents with whom it interacts. For some agent interactions, such as those involving commerce, agents will simply inherit the reputation of their human owner, sharing, for example, their owner\u27s credit rating and financial capability. For other types of interactions, such as those involving information gathering, an agent will determine its own reputation through its efforts at gathering and distilling information. An agent with a reputation for conducting thorough searches will be trusted by other agents wishing to use its Web search results

Temperature-controlled interlayer exchange coupling in strong/weak ferromagnetic multilayers: a thermo-magnetic Curie-switch

We investigate a novel type of interlayer exchange coupling based on driving a strong/weak/strong ferromagnetic tri-layer through the Curie point of the weakly ferromagnetic spacer, with the exchange coupling between the strongly ferromagnetic outer layers that can be switched, on and off, or varied continuously in magnitude by controlling the temperature of the material. We use Ni-Cu alloy of varied composition as the spacer material and model the effects of proximity-induced magnetism and the interlayer exchange coupling through the spacer from first principles, taking into account not only thermal spin-disorder but also the dependence of the atomic moment of Ni on the nearest-neighbor concentration of the non-magnetic Cu. We propose and demonstrate a gradient-composition spacer, with a lower Ni-concentration at the interfaces, for greatly improved effective-exchange uniformity and significantly improved thermo-magnetic switching in the structure. The reported magnetic multilayer materials can form the base for a variety of novel magnetic devices, such as sensors, oscillators, and memory elements based on thermo-magnetic Curie-switching in the device.Comment: 15 pages, 5 figure

Advanced Grid programming with components: a biometric identification case study

Component-oriented software development has been attracting increasing attention for building complex distributed applications. A new infrastructure supporting this advanced concept is our prototype component framework based on the Grid component model. This paper provides an overview of the component framework and presents a case study where we utilise the component-oriented approach to develop a business process application for a biometric identification system. We then introduce the tools being developed as part of an integrated development environment to enable graphical component-based development of Grid applications. Finally, we report our initial findings and experiences of efficiently using the component framework and set of software tools

Thermally-induced lactosylation of whey proteins: Identification and synthesis of lactosylated β-lactoglobulin epitope

The high temperatures used in the production of milk may induce modifications in proteins structure. Due to occurrence of the Maillard reaction, lactose binds lysine residues in proteins, affecting the nutritional value. Milk is also an important source of allergenic proteins (i.e., caseins, β-lactoglobulin and α-lactalbumin). Thus, this modification may also affect the allergenicity of these proteins. Focusing on milk whey proteins, a screening on different Ultra High Temperatures (UHT) and pasteurized milk samples was performed to identify lactosylation sites, in particular in protein known epitopes, and to verify the correlation between lactosylation and the harshness of the treatment. Whey proteins were extracted from milk samples after caseins precipitations at pH 4.6 and, after chymotryptic and tryptic in solution digestion, peptides were analysed by UPLC-MS and LTQ-Orbitrap. Results show the presence of lactosylated lysine residues in several known epitopes. Then, a β-lactoglobulin epitope was selected and synthesized by solid phase synthesis followed by in solution lactosylation, obtaining high reaction yields and purities. The synthesis of lactosylated allergenic epitopes, described here for the first time, is a useful tool for further studies on the technological impacts on food allergenicity

Germanium Detector with Internal Amplification for Investigation of Rare Processes

Device of new type is suggested - germanium detector with internal amplification. Such detector having effective threshold about 10 eV opens up fresh opportunity for investigation of dark matter, measurement of neutrino magnetic moment, of neutrino coherent scattering at nuclei and for study of solar neutrino problem. Construction of germanium detector with internal amplification and perspectives of its use are described.Comment: 13 pages, latex, 3 figures, report at NANP-99, International Conference on Non-Accelerator Physics, Dubna, Russia, June 29- July 3, 1999. To be published in the Proceeding