Induction of Cytokinin-Independent Tobacco Tissues by Substituted Fluorenes

Two morphactins and three aminofluorenes initiated the formation of compact tissue nodules in hormone-dependent tobacco callus cultures. These nodules, upon subculture, behaved like partially transformed plant tumors. They grew on cytokinin-free media, while control callus and nonnodule tissue still required an exogenous cytokinin source. The data indicate that substituted fluorenes, including carcinogenic aminofluorenes, can cause a neoplastic growth response in cultured tobacco tissues. Of particular interest in this study is the finding that a directed and heritable cellular change is induced in tobacco tissue in which a specific (the endogenous cytokinin) biosynthetic system is regularly and persistently activated

Feasibility Study of Variance Reduction in the THUNDER Campaign-Level Model

As an Air Force Chief of Staff endorsed topic, Air Force Studies and Analyses Agency (AFSAA) requested an effective and efficient way to reduce the variance in analysis results from THUNDER. THUNDER is a large-scale discrete event simulation of campaign-level military operations and is used to examine issues involving the utility and effectiveness of air and space power in a theater-level, joint warfare context. Given the large number of stochastic components within THUNDER, results are produced with highly variable measures of effectiveness (MOEs), causing difficulties in evaluating alternative force structures, weapon systems, etc. This work responds to AFSAA\u27s request by examining the application of Common Random Numbers (CRN), Antithetic Variates (AV), Control Variates (CV), and a combination of AVs and CVs. The difference between the standard output and variance reduced output halfwidths for 95% confidence intervals were examined. Analysis of the correlation between MOEs and the random inputs in the CV technique provided insight into the workings of THUNDER. A new, state of the art combined multiple recursive generator was incorporated into THUNDER to synchronize the random inputs for CRN and AV. The result is methodology for implementing all four variance reduction techniques

ASSESSING THE READINESS OF RELATIVES TO UNDERGO CASCADE GENETIC TESTING FOR INHERITED PREDISPOSITIONS TO CANCER USING THE TRANSTHEORETICAL MODEL STAGES OF CHANGE

National guidelines recommend cascade genetic testing (CGT) for blood relatives after a cancer predisposition gene mutation is identified in an individual. Despite recommendations for CGT, only 30-60% of first-degree relatives (FDRs) complete CGT. The proportion of untested relatives who are planning to have CGT is unknown. We used the Transtheoretical Model to assess the readiness (stage of change) for CGT among living, untested FDRs at-risk for a hereditary predisposition to cancer. An anonymous, online survey was open to U.S. adults with an autosomal dominant, adult-onset, hereditary predisposition to cancer. Participants reported demographic information, their genetic testing information, and information on FDRs (the number of each relative, vital status, uptake of CGT, and readiness for CGT among those alive and untested). Data were analyzed using descriptive statistics, non-parametric McNemar, Friedman, Wilcoxon Signed Rank, Kruskal-Wallis, and Mann-Whitney tests. A two-sided p-value of 0.05 was considered statistically significant

Identification and Classification of Player Types in Massive Multiplayer Online Games using Avatar Behavior

The purpose of our research is to develop an improved methodology for classifying players (identifying deviant players such as terrorists) through multivariate analysis of data from avatar characteristics and behaviors in massive multiplayer online games (MMOGs). To build our classification models, we developed three significant enhancements to the standard Generalized Regression Neural Networks (GRNN) modeling method. The first enhancement is a feature selection technique based on GRNNs, allowing us to tailor our feature set to be best modeled by GRNNs. The second enhancement is a hybrid GRNN which allows each feature to be modeled by a GRNN tailored to its data type. The third enhancement is a spread estimation technique for large data sets that is faster than exhaustive searches, yet more accurate than a standard heuristic. We applied our new techniques to a set of data from the MMOG, Everquest II, to identify deviant players (\u27gold farmers\u27). The identification of gold farmers is similar to labeling terrorists in that the ratio of gold farmer to standard player is extremely small, and the in-game behaviors for a gold farmer have detectable differences from a standard player. Our results were promising given the difficulty of the classification process, primarily the extremely unbalanced data set with a small number of observations from the class of interest. As a screening tool our method identifies a significantly reduced set of avatars and associated players with a much improved probability of containing a number of players displaying deviant behaviors. With further efforts at improving computing efficiencies to allow inclusion of additional features and observations with our framework, we expect even better results

Tomorrow is Another Day: Information Systems Governance

In many organizations, the Chief Information Officer is considered to preside over a separate function, providing a service to the business. Discussions about governance are confined to properties of this service, e.g. through a service level agreement. Members of the CIO’s staff are often seen as technical experts possessing esoteric skills desired but not understood by other staff. Many researchers have observed a need for businesses to avoid such fragmentation to reap the full benefits of investment in ICT’s. However, this research is itself often fragmented – focusing sometimes on software, sometimes on architectures. This paper argues that IS governance should form an integral part of strategic business management. We advocate a shift of perspective in management of IS, from leadership to facilitation. People at all levels require empowerment and support to develop their own IS ‘capability’; to make the best use of available technologies and information in context. There is evidence to show that input from a wider community within organizations can lead to an improved realization of value from information technology. The paper will discuss methods which can provide appropriate support for individuals to achieve this

How does the chromatin fiber deal with topological constraints?

In the nuclei of eukaryotic cells, DNA is packaged through several levels of compaction in an orderly retrievable way that enables the correct regulation of gene expression. The functional dynamics of this assembly involves the unwinding of the so-called 30 nm chromatin fiber and accordingly imposes strong topological constraints. We present a general method for computing both the twist and the writhe of any winding pattern. An explicit derivation is implemented for the chromatin fiber which provides the linking number of DNA in eukaryotic chromosomes. We show that there exists one and only one unwinding path which satisfies both topological and mechanical constraints that DNA has to deal with during condensation/decondensation processes.Comment: Presented in Nature "News and views in brief" Vol. 429 (13 May 2004). Movies available at http://www.lptl.jussieu.fr/recherche/operationE_fichiers/Page_figurePRL.htm

An Asynchronous Circuit Design Language (ACDL)

This correspondence describes a special purpose Asynchronous Circuit Design Language (ACDL) for specifying the terminal behavior of asynchronous sequential circuits. The language is a valuable tool for formalizing and documenting asynchronous designs, as well as providing a user interface to a completely automated synthesis system. The language includes many special features which permit quick and precise specification of terminal behavior and is best suited for problems that are currently being described informally by word statements. Copyright © 1974 by The Institute of Electrical and Electronics Engineers, Inc