Hyperbolic regression analysis for kinetics, electrophoresis, ELISA, RIA, Bradford, Lowry, and other applications

Hyperbolic regression analysis is an effective method for fitting experimental data points obtained from a variety of experiments in molecular biology, including enzyme kinetics, agarose gel electrophoresis of DNA fragments, SDS-polyacrylamide gel electrophoresis of proteins, enzyme-linked immunosorbent assays (ELISA), radioimmunoassays (RIA), Bradford protein quantitation assays, Lowry protein assays, and other applications. Hyperbolic regression yields excellent fitted curves without the biases that are introduced by carrying out linear regression on double reciprocal coordinates, and it produces one simple equation, encompassing all the data points, that can be used easily in a pocket calculator to estimate the values of unknown samples from the known standards.     

Pointcuts, advice, refinements, and collaborations: similarities, differences, and synergies

Aspect-oriented programming (AOP) is a novel programming paradigm that aims at modularizing complex software. It embraces several mechanisms including (1) pointcuts and advice as well as (2) refinements and collaborations. Though all these mechanisms deal with crosscutting concerns, i.e., a special class of design and implementation problems that challenge traditional programming paradigms, they do so in different ways. In this article we explore their relationship and their impact on modularity, which is an important prerequisite for reliable and maintainable software. Our exploration helps researchers and practitioners to understand their differences and exposes which mechanism is best used for which problem.     

Louis Kruh,Cryptologist, Editor,Activist

Abstract

The double transposition cipher was considered to be one of the most secure types of manual ciphers. It was extensively used in both World Wars and during the Cold War. In 1999, Otto Leiberich, the former head of the German federal office for information security, suggested that a double transposition challenge be published with specific parameters designed to ensure its security. Such a challenge was published by Klaus Schmeh in 2007. In November 2013, the authors solved the challenge using a ciphertext-only hill climbing attack. They also solved the challenge using a dictionary attack. In this article, they describe both methods, which are based on a “divide-and-conquer” approach. They additionally discuss the impact of their solutions with respect to the general security of the double transposition cipher.     

Slope Intervals,Generalized Gradients,Semigradients, Slant Derivatives,and Csets

Many practical optimization problems are nonsmooth, and derivative-type methods cannot be applied. To overcome this difficulty, there are different concepts to replace the derivative of a function f : : interval slopes, semigradients, generalized gradients, and slant derivatives are some examples. These approaches generalize the success of convex analysis, and are effective in optimization. However, with the exception of interval slopes, it is not clear how to automatically compute these; having a general analogue to the chain rule, interval slopes can be computed with automatic differentiation techniques. In this paper we study the relationships among these approaches for nonsmooth Lipschitz optimization problems in finite dimensional Euclidean spaces. Inclusion theorems concerning the equivalence of these concepts when there exist one sided derivatives in one dimension and in multidimensional cases are proved separately. Valid enclosures are produced. Under containment set (cset) theory, for instance, the cset of the gradient of a locally Lipschitz function f near x is included in its generalized gradient.     

Across disciplines: risk, design, method, process, and tools

In the search for solutions to make software development more predictable and controllable, one often looks for parallels in other disciplines such as architecture, bridge construction, and so on. The article looks at software development from the perspective of the electrical industry. Inspired by their management tradition, ATH techniek b.v. has learned to apply proven management techniques to software development. Simple and commonsense principles yield excellent results; for instance, developers reduced risk by estimating project effort using two different measures and by controlling execution. Comparing the software development processes with what goes on in the rest of the company or another application domain can be instructive     

Electronic Markets, Hierarchies, Hubs, and Intermediaries

The impact of information technologies on organizations is difficult to predict, although critical for developing comprehensive organizational strategies. Much of the difficulty is traceable to the treatment of all information technologies as a single factor, when in fact different technologies may have drastically different impacts on the organization. Specifically, the distinction between two general classes of technologies, communication and information processing technologies, is studied. An analytical model is developed to show that these two classes of technologies have exactly the opposite impacts on the organization. Moreover, the impact also depends on the organization, and its existing structure. Communication intensive and processing intensive organizational structures are distinguished and they are shown to be impacted differently by information technologies. An analytical framework is developed to show a continuum of organizational structures, depending on their relative communication and processing intensity, and the effect of various technologies is shown to be to move the organization along that continuum. Communication and information processing technologies are shown to move the organization in opposing directions. Finally, the analytical framework is shown to be robust and valid under a wide variety of conditions, covering most real life organizations.     

Phrenology, astrology, risk, and product quality

Engineering is the act of making intelligent tradeoffs and compromises among conflicting and sometimes mutually exclusive goals. To improve product performance, the die size might need to increase, which diminishes the chip's economic attractiveness. Assessing risk and product quality is not an exact science. Nevertheless, the computing industry's future rests as much on our success in achieving product quality as it does in continuing to innovate in circuits and microarchitectures     

ALIENATION,EARLY SOCIALISM,PERESTROIKA, AND LIBERTY

The essential contradiction of the process of perestroika is that between alienation and liberty. Current Soviet society is a historically preliminary form of socialist society. The essence of early socialism is a rise in new quasi-socialist forms of alienation. Seven strata of alienation have appeared in the Soviet Union—alienation from participation in government, from the results of work, from the organization of work, from human needs, from self-consciousness, from personal safety, and from laws. The theoretical basis of liberty is that it is the antipole of alienation.     

Petri nets, algebras, morphisms, and compositionality

It is shown how a category of Petri nets can be viewed as a subcategory of two sorted algebras over multisets. This casts Petri nets in a familiar framework and provides a useful idea of morphism on nets different from the conventional definition—the morphisms here respect the behaviour of nets. The categorical constructions which result provide a useful way to synthesise nets and reason about nets in terms of their components; for example, various forms of parallel composition of Petri nets arise naturally from the product in the category. This abstract setting makes plain a useful functor from the category of Petri nets to a category of spaces of invariants and provides insight into the generalisations of the basic definition of Petri nets—for instance, the coloured and higher level nets of Kurt Jensen arise through a simple modification of the sorts of the algebras underlying nets. Further, it provides a smooth formal relation with other models of concurrency such as Milner's calculus of communicating systems (CCS) and Hoare's communicating sequential processes (CSP), though this is only indicated in this paper.     

Strategy, Strategy, Strategy

The year 1987 may well be remembered as the Year of Strategy. The ideas of using information as a strategic weapon, of creating information systems that advance corporate strategic purposes, and of using information systems for competitive advantage were everywhere - at professional meetings, in journal articles, and in books. In a previous issue (Winter 1987), I reviewed The Information Edge, by N. Dean Meyer and Mary E. Boone, which followed this theme. Since then, I have been bombarded with a flood of books on the subject; four of them are reviewed in this column.     

MT Summit,Hakone, Kanagawa-ken,Japan September 17–19, 1987

At the time of the MT Summit, the author was spending a one-year leave of absence from Manchester as a Research Fellow at Toshiba Corporation's R&;D Center, Kawasaki, and I would like to acknowledge that it was they who made it possible for me to attended the summit. For this I express my gratitude. The opinions expressed in this review are however entirely personal views, and do not necessarily represent the opinions of Toshiba Corporation or any of its employees.     

Plagiarism, originality, assemblage

Although students work and live in a remix culture, composition pedagogy does not always value the discursive practices of that culture, especially when it comes to producing written work for academic contexts. The reasons for these views are historically determined and tied, at least in part, to relatively traditional notions of authorship and creativity. But “writers” in other contexts, both disciplinary and popular, have developed interesting and useful remix approaches that can aid invention, leverage intellectual and physical resources, and dramatize the social dimensions of composing in this day and age. These approaches, however, ask teachers to reconsider taken-for-granted assumptions about plagiarism and originality.     

Model predictive control springer,Berlin, 1999, ISBN 3540762418, 280 pages

This volume is a recent addition to the Camacho and Bordons' book ‘Model Predictive Control in the Process Industry’, edited by Springer Verlag. The book presents a complete review of the theory and applications of Model Predictive Control MPC, from the simple unconstrained SISO case to the more complex constrained MIMO situations. Special attention is given to the Generalized Predictive Controller that is one of the most known and cited MPC strategies. In all the chapters the results are illustrated with simulation examples and also with some experimental results that validated the controllers and tuning rules analyzed in the book. Copyright © 2003 John Wiley & Sons, Ltd.