Dynamic control and information processing in the Belousov-Zhabotinsky reaction using a coevolutionary algorithm

We propose that the behavior of nonlinear media can be controlled dynamically through coevolutionary systems. In this study, a light-sensitive subexcitable Belousov-Zhabotinsky reaction is controlled using a heterogeneous cellular automaton. A checkerboard image comprising of varying light intensity cells is projected onto the surface of a catalyst-loaded gel resulting in rich spatiotemporal chemical wave behavior. The coevolved cellular automaton is shown to be able to either increase or decrease chemical activity through dynamic control of the light intensity within each cell in both simulated and real chemical systems. The approach is then extended to construct a number of simple logical functions. © 2008 American Institute of Physics

Towards unconventional computing through simulated evolution: Control of nonlinear media by a learning classifier system

We propose that the behavior of nonlinear media can be controlled automatically through evolutionary learning. By extension, forms of unconventional computing (viz., massively parallel nonlinear computers) can be realized by such an approach. In this initial study a light-sensitive subexcitable Belousov-Zhabotinsky reaction in which archeckerboard image, composed of cells of varying light intensity projected onto the surface of a thin silica gel impregnated with a catalyst and indicator, is controlled using a learning classifier system. Pulses of wave fragments are injected into the checkerboard grid, resulting in rich spatiotemporal behavior, and a learning classifier system is shown to be able to direct the fragments to an arbitrary position through dynamic control of the light intensity within each cell in both simulated and real chemical systems. Similarly, a learning classifier system is shown to be able to control the electrical stimulation of cultured neuronal networks so that they display elementary learning. Results indicate that the learned stimulation protocols identify seemingly fundamental properittes of in vitro neuronal networks. Use of another learning scheme presented in the literature confirms that such fundamental behavioral characteristics of a given network must be considered in training experiments. © 2008 Massachusetts Institute of Technology

The virtual city with real decisions: ITEAM

This paper introduces an integrated transportation and energy activity-based model (iTEAM), a tool for the evaluation of “green policies” aimed at enhancing sustainability and well-being. The model will simulate individual/household and organization/firm agents at a micro level. The aggregate simulation results will help forecast the impacts of policies on transport system efficiency and land-use dynamics in the simulated areas. This process is complemented by Material Flow Accounting (MFA) techniques, which account for a range of factors including wellbeing, waste production, and carbon emissions to calculate the urban metabolism.Peer Reviewe

Finding Higgs bosons heavier than 2 m_W in dileptonic W-boson decays

We reconsider observables for discovering a heavy Higgs boson (with m_h > 2m_W) via its di-leptonic decays h -> WW -> l nu l nu. We show that observables generalizing the transverse mass that take into account the fact that both of the intermediate W bosons are likely to be on-shell give a significant improvement over the variables used in existing searches. We also comment on the application of these observables to other decays which proceed via narrow-width intermediates.Comment: v1:4 pages, 1 figure; v2: 6 pages, 2 figures, substantially revise

One-class Gaussian process regressor for quality assessment of transperineal ultrasound images

The use of ultrasound guidance in prostate cancer radiotherapy workflows is not widespread. This can be partially attributed to the need for image interpretation by a trained operator during ultrasound image acquisition. In this work, a one-class regressor, based on DenseNet and Gaussian processes, was implemented to assess automatically the quality of transperineal ultrasound images of the male pelvic region. The implemented deep learning approach achieved a scoring accuracy of 94%, a specificity of 95% and a sensitivity of 93% with respect to the majority vote of three experts, which was comparable with the results of these experts. This is the first step towards a fully automatic workflow, which could potentially remove the need for image interpretation and thereby make the use of ultrasound imaging, which allows real-time volumetric organ tracking in the RT environment, more appealing for hospitals

Implementation of Glider Guns in the Light-Sensitive Belousov-Zhabotinsky Medium

In cellular automata models a glider gun is an oscillating pattern of non-quiescent states that periodically emits traveling localizations (gliders). The glider streams can be combined to construct functionally complete systems of logical gates and thus realize universal computation. The glider gun is the only means of ensuring the negation operation without additional external input and therefore is an essential component of a collision-based computing circuit. We demonstrate the existence of glider gun like structures in both experimental and numerical studies of an excitable chemical system -- the light-sensitive Belousov-Zhabotinsky reaction. These discoveries could provide the basis for future designs of collision-based reaction-diffusion computers.Comment: Accepted for publication in Physical Review

2019: A Changing International Order? Implications for the Security Environment

KCIS2019 examined the implications of the changing international order for international security. It studied the hypercompetitive, multipolar environment in which we find ourselves, marked by a persistent struggle for influence and position within a “grey zone” of competition. This edited collection features contributions from academic and military experts who have examined the future of the liberal international order and what is at stake. These evidence-based examinations discuss the challenges to the order, and why it has been so difficult to articulate a compelling narrative to support the continuation of American leadership.https://press.armywarcollege.edu/monographs/1922/thumbnail.jp

The XMM Cluster Survey: The Stellar Mass Assembly of Fossil Galaxies

This paper presents both the result of a search for fossil systems (FSs) within the XMM Cluster Survey and the Sloan Digital Sky Survey and the results of a study of the stellar mass assembly and stellar populations of their fossil galaxies. In total, 17 groups and clusters are identified at z < 0.25 with large magnitude gaps between the first and fourth brightest galaxies. All the information necessary to classify these systems as fossils is provided. For both groups and clusters, the total and fractional luminosity of the brightest galaxy is positively correlated with the magnitude gap. The brightest galaxies in FSs (called fossil galaxies) have stellar populations and star formation histories which are similar to normal brightest cluster galaxies (BCGs). However, at fixed group/cluster mass, the stellar masses of the fossil galaxies are larger compared to normal BCGs, a fact that holds true over a wide range of group/cluster masses. Moreover, the fossil galaxies are found to contain a significant fraction of the total optical luminosity of the group/cluster within 0.5R200, as much as 85%, compared to the non-fossils, which can have as little as 10%. Our results suggest that FSs formed early and in the highest density regions of the universe and that fossil galaxies represent the end products of galaxy mergers in groups and clusters. The online FS catalog can be found at http://www.astro.ljmu.ac.uk/~xcs/Harrison2012/XCSFSCat.html.Comment: 30 pages, 50 figures. ApJ published version, online FS catalog added: http://www.astro.ljmu.ac.uk/~xcs/Harrison2012/XCSFSCat.htm

Isolation, characterization and comparison of Atlantic and Chinook salmon growth hormone 1 and 2

<p>Abstract</p> <p>Background</p> <p>Growth hormone (GH) is an important regulator of skeletal growth, as well as other adapted processes in salmonids. The GH gene (<it>gh</it>) in salmonids is represented by duplicated, non-allelic isoforms designated as <it>gh1 </it>and <it>gh2</it>. We have isolated and characterized <it>gh</it>-containing bacterial artificial chromosomes (BACs) of both Atlantic and Chinook salmon (<it>Salmo salar </it>and <it>Oncorhynchus tshawytscha</it>) in order to further elucidate our understanding of the conservation and regulation of these loci.</p> <p>Results</p> <p>BACs containing <it>gh1 </it>and <it>gh2 </it>from both Atlantic and Chinook salmon were assembled, annotated, and compared to each other in their coding, intronic, regulatory, and flanking regions. These BACs also contain the genes for skeletal muscle sodium channel oriented in the same direction. The sequences of the genes for interferon alpha-1, myosin alkali light chain and microtubule associated protein Tau were also identified, and found in opposite orientations relative to <it>gh1 </it>and <it>gh2</it>. Viability of each of these genes was examined by PCR. We show that transposon insertions have occurred differently in the promoters of <it>gh</it>, within and between each species. Other differences within the promoters and intronic and 3'-flanking regions of the four <it>gh </it>genes provide evidence that they have distinct regulatory modes and possibly act to function differently and/or during different times of salmonid development.</p> <p>Conclusion</p> <p>A core proximal promoter for transcription of both <it>gh1 </it>and <it>gh2 </it>is conserved between the two species of salmon. Nevertheless, transposon integration and regulatory element differences do exist between the promoters of <it>gh1 </it>and <it>gh2</it>. Additionally, organization of transposon families into the BACs containing <it>gh1 </it>and for the BACs containing <it>gh2</it>, are very similar within orthologous regions, but much less clear conservation is apparent in comparisons between the <it>gh1</it>- and <it>gh2</it>-containing paralogous BACs for the two fish species. This is consistent with the hypothesis that a burst of transposition activity occurred during the speciation events which led to Atlantic and Pacific salmon. The Chinook and other <it>Oncorhynchus </it>GH1s are strikingly different in comparison to the other GHs and this change is not apparent in the surrounding non-coding sequences.</p