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Journal ArticleDOI

Phd by thesis

01 Apr 1988-Nature (Nature Publishing Group)-Vol. 332, Iss: 6166, pp 676-676
TL;DR: In this paper, a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) is presented.
Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

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Citations
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Proceedings ArticleDOI
26 Jun 1989
TL;DR: This paper describes the referring expression generation mechanisms used in EPICURE, a computer program which produces natural language descriptions of cookery recipes with an underlying ontology which permits the representation of non-singular entities and a PATR-like unification grammar to produce surface linguistic strings.
Abstract: This paper describes the referring expression generation mechanisms used in EPICURE, a computer program which produces natural language descriptions of cookery recipes. Major features of the system include: an underlying ontology which permits the representation of non-singular entities; a notion of discriminatory power, to determine what properties should be used in a description; and a PATR-like unification grammar to produce surface linguistic strings.

237 citations

Journal ArticleDOI
TL;DR: In this paper, the authors describe the basic properties of infinite disorder fixed points, which are realized at critical points, and of strong disorder fixedpoints, which control the singular behaviors in the Griffiths-phases.
Abstract: There is a large variety of quantum and classical systems in which the quenched disorder plays a dominant r\^ole over quantum, thermal, or stochastic fluctuations : these systems display strong spatial heterogeneities, and many averaged observables are actually governed by rare regions. A unifying approach to treat the dynamical and/or static singularities of these systems has emerged recently, following the pioneering RG idea by Ma and Dasgupta and the detailed analysis by Fisher who showed that the Ma-Dasgupta RG rules yield asymptotic exact results if the broadness of the disorder grows indefinitely at large scales. Here we report these new developments by starting with an introduction of the main ingredients of the strong disorder RG method. We describe the basic properties of infinite disorder fixed points, which are realized at critical points, and of strong disorder fixed points, which control the singular behaviors in the Griffiths-phases. We then review in detail applications of the RG method to various disordered models, either (i) quantum models, such as random spin chains, ladders and higher dimensional spin systems, or (ii) classical models, such as diffusion in a random potential, equilibrium at low temperature and coarsening dynamics of classical random spin chains, trap models, delocalization transition of a random polymer from an interface, driven lattice gases and reaction diffusion models in the presence of quenched disorder. For several one-dimensional systems, the Ma-Dasgupta RG rules yields very detailed analytical results, whereas for other, mainly higher dimensional problems, the RG rules have to be implemented numerically. If available, the strong disorder RG results are compared with another, exact or numerical calculations.

233 citations


Cites background or methods from "Phd by thesis"

  • ...The aging properties of trap models have been much studied, either in the mean field version [59, 46, 135, 210], or in the 1D version [146, 51, 53], which naturally appears in various physical contexts [30, 14, 184], and which presents two characteristic time scales for aging, in contrast with the mean field case....

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  • ...Bouchaud [52, 53] with scaling arguments and numerical simulations....

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Book
23 Sep 2014
TL;DR: Finding Causal Structure is an introduction to causal modeling and an extensive collection of applications to real and simulated data.
Abstract: This is a beautifully produced book. The cover is heavy, the typeface and graphics are clear and easy to read, and the margins are wide for the scholarly reader's notes. The title and subtitle include nine of the most powerful key words imaginable. Unlike most of those who write about causal models, the authors are real philosophers, and they have acquired a Foreword by a Nobel Prize winner who is a seminal contributor to all of the fields they address. The first sentence of the book is "This book is about a computer program, TETRAD." That characterization seems a bit modest, even if this particular computer program (as Herbert Simon says) "can be viewed as a normative theory of how to induce causal models from empirical, nonexperimental data" (p. xiii). In reality, however, Discovering Causal Structure is more modest than its title implies. It promises more than it delivers. There are two principal components to the book, each of which can be broken into two subparts. The first component consists of a 57-page essay entitled "Artificial Intelligence and Nonexperimental Science" (chapters 1-3) and a 12-page "Brief History of Heuristic Search in Applied Statistics" (chapter 9). These pages contain what Simon, in his Foreword, applauds as "a careful discussion of the discovery process and detailed answers to the objections that have been raised.., .against causal modeling." The second component addresses the computer program directly. Chapters 11 and 12 (60 pages) contain the user's manual for TETRAD, and chapters 4-8 (172 pages) provide detailed descriptions of what the program does, including an introduction to causal modeling and an extensive collection of applications to real and simulated data.

232 citations

Journal ArticleDOI
TL;DR: EPR studies of P700(+*) in frozen solution and single crystals indicate a large asymmetry in the electron spin and charge distribution towards one Chl of the dimer, suggesting that the unpaired electron would predominantly reside on the Chl a.

231 citations


Cites background from "Phd by thesis"

  • ...This is due to the large particle size (molecular mass of a PSI monomer is V330 kDa) which prevents a tumbling in solution that is fast enough to average out the anisotropic g and hyper¢ne contributions [26,51]....

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Journal ArticleDOI
TL;DR: A simple model is proposed that links the transition from continuous to discontinuous shear thickening in dense granular pastes to distinct lubrication regimes in the particle contacts and shows that the suspension's volume fraction and the boundary lubrication friction coefficient control the nature of the shear-thickening transition.
Abstract: We propose a simple model, supported by contact-dynamics simulations as well as rheology and friction measurements, that links the transition from continuous to discontinuous shear thickening in dense granular pastes to distinct lubrication regimes in the particle contacts. We identify a local Sommerfeld number that determines the transition from Newtonian to shear-thickening flows, and then show that the suspension's volume fraction and the boundary lubrication friction coefficient control the nature of the shear-thickening transition, both in simulations and experiments.

231 citations


Cites background from "Phd by thesis"

  • ...Thus, in the absence of transient migration effects [44], the local volume fraction and friction coefficient determine the stable microscopic flow mechanism, which is either CST or DST [44, 47, 48]....

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References
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Journal ArticleDOI
TL;DR: A new family of highly fluorescent indicators has been synthesized for biochemical studies of the physiological role of cytosolic free Ca2+ using an 8-coordinate tetracarboxylate chelating site with stilbene chromophores that offer up to 30-fold brighter fluorescence.

21,582 citations


"Phd by thesis" refers background in this paper

  • ...members of this group were produced by Tsien and colleagues [1, 10, 11]....

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  • ...The introduction of Ca 2+ -sensitive fluorescent dyes more than twenty years ago and their permanent improvement [10] enabled investigators to gain unprecedented insights into the mechanisms of cellular signalling....

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ReportDOI
01 Nov 1990
TL;DR: This report will establish methods for performing a domain analysis and describe the products of the domain analysis process to illustrate the application of domain analysis to a representative class of software systems.
Abstract: : Successful Software reuse requires the systematic discovery and exploitation of commonality across related software systems. By examining related software systems and the underlying theory of the class of systems they represent, domain analysis can provide a generic description of the requirements of that class of systems and a set of approaches for their implementation. This report will establish methods for performing a domain analysis and describe the products of the domain analysis process. To illustrate the application of domain analysis to a representative class of software systems, this report will provide a domain analysis of window management system software.

4,420 citations

Journal ArticleDOI
TL;DR: The straw person model (SPM) as mentioned in this paper has been proposed to explain the orientation effects of active galactic nuclei (AGN) and quasars in the line of sight (LOS) images.
Abstract: Because the critical central regions of Active Galactic Nuclei (AGN) and quasars are strongly nonspherical but spatially unresolved, orientation effects have been the source of much confusion. In fact, it now appears that much of the variety in AGN types is just the result of varying orientation relative to the line of sight. We can define an extreme hypothesis,, the straw person model (SPM), in which there are two basic types of AGN: the radio quiets and the radio louds. For each type there is a range in intrinsic luminosity, and the luminosity controls some properties such as the Fanaroff and Riley classes. However, at a given intrinsic luminosity, all other properties such as spectroscopic classification and VLBI component speeds are ascribed to orientation. This model is only a caricature of the unification idea, and is already ruled out on many grounds, but it will be useful for organizing the discussion. I’ll describe what I consider to be convincing evidence that orientation effects are important and widespread. The true situation may be in some sense half way between the SPM and the hypothesis that orientation doesn’t affect classification at aIl. To us optimists, the orienration cup is half full rather than half empty. Although it is too soon to say for sure, the hypothesis that most objects’ classifications would be different if seen from other directions is a tenable one today.

4,005 citations

Journal ArticleDOI
TL;DR: This Review assembles the current knowledge on the isolation of microfibrillated cellulose from wood and its application in nanocomposites; the preparation of nanocrystalline cellulose and its use as a reinforcing agent; and the biofabrication of bacterial nanocellulose, as well as its evaluation as a biomaterial for medical implants.
Abstract: Cellulose fibrils with widths in the nanometer range are nature-based materials with unique and potentially useful features. Most importantly, these novel nanocelluloses open up the strongly expanding fields of sustainable materials and nanocomposites, as well as medical and life-science devices, to the natural polymer cellulose. The nanodimensions of the structural elements result in a high surface area and hence the powerful interaction of these celluloses with surrounding species, such as water, organic and polymeric compounds, nanoparticles, and living cells. This Review assembles the current knowledge on the isolation of microfibrillated cellulose from wood and its application in nanocomposites; the preparation of nanocrystalline cellulose and its use as a reinforcing agent; and the biofabrication of bacterial nanocellulose, as well as its evaluation as a biomaterial for medical implants.

3,452 citations

Journal ArticleDOI
TL;DR: The solid electrolyte interphase (SEI) is a protecting layer formed on the negative electrode of Li-ion batteries as a result of electrolyte decomposition, mainly during the first cycle as discussed by the authors.

2,386 citations