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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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Journal ArticleDOI
B. P. Abbott1, R. Abbott1, Rana X. Adhikari2, A. Ageev3  +404 moreInstitutions (33)
TL;DR: The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24), which translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.
Abstract: We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10^(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10^(-5) for the four closest pulsars.

146 citations


Cites methods from "Phd by thesis"

  • ...In this paper we exploit the improved stationarity of the instruments that make it reasonable to assume the noise floor is constant over periods of 30min [8]....

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  • ...Here we extend the former method [2, 8] and apply it to 28 isolated pulsars....

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Journal ArticleDOI
TL;DR: In this article, the Breit frame in deepinelastic positron-proton scattering over a large range of four-momentum transfers 5 Q^2 15000 GeV^2 and transverse jet energies 7 E_T 60 GeV.
Abstract: Jet production is studied in the Breit frame in deep-inelastic positron-proton scattering over a large range of four-momentum transfers 5 Q^2 15000 GeV^2 and transverse jet energies 7 E_T 60 GeV. The analysis is based on data corresponding to an integrated luminosity of L_int \simeq 33 pb^(-1) taken in the years 1995-1997 with the H1 detector at HERA at a center-of-mass energy sqrt(s)=300 GeV. Dijet and inclusive jet cross sections are measured multi-differentially using k_perp and angular ordered jet algorithms. The results are compared to the predictions of perturbative QCD calculations in next-to-leading order in the strong coupling constant alphas.QCD fits are performed in which alphas and the gluon density in the proton are determined separately. The gluon density is found to be in good agreement with results obtained in other analyses using data from different processes. The strong coupling constant is determined to be alphas(MZ)=0.1186+-0.0059. In addition an analysis of the data in which both alphas and the gluon density are determined simultaneously is presented.

146 citations


Cites background or methods from "Phd by thesis"

  • ...the inclusive angular ordered algorithm (Aachen algorithm ) as proposed in [5, 8]....

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  • ...Since standard com putations of NLO jet cross sections are time consuming the method [5] is used of pre-convoluting the perturbative coefficients with suitably defined functions which can then be folded with the p arton densities and s for a fast computation of the NLO cross section....

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  • ...To test their applicability for the correction procedure, d tailed comparisons have been made of the simulated event samples and the data for a multitude of jet distributions [5]....

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  • ...The uncertainty from the model and the parameter dependence of these predictions is always below 3% [5, 8]....

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  • ...The exact definiti o s taken from [5]....

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Journal ArticleDOI
TL;DR: The focus then centers on current synthesis strategies for graphene and their weaknesses in terms of electronics applications are highlighted, and the properties of graphene that make it so attractive as a material for electronics is introduced to the reader.
Abstract: Graphene has a multitude of striking properties that make it an exceedingly attractive material for various applications, many of which will emerge over the next decade. However, one of the most promising applications lie in exploiting its peculiar electronic properties which are governed by its electrons obeying a linear dispersion relation. This leads to the observation of half integer quantum hall effect and the absence of localization. The latter is attractive for graphene-based field effect transistors. However, if graphene is to be the material for future electronics, then significant hurdles need to be surmounted, namely, it needs to be mass produced in an economically viable manner and be of high crystalline quality with no or virtually no defects or grains boundaries. Moreover, it will need to be processable with atomic precision. Hence, the future of graphene as a material for electronic based devices will depend heavily on our ability to piece graphene together as a single crystal and define its edges with atomic precision. In this progress report, the properties of graphene that make it so attractive as a material for electronics is introduced to the reader. The focus then centers on current synthesis strategies for graphene and their weaknesses in terms of electronics applications are highlighted.

145 citations


Cites background from "Phd by thesis"

  • ...[29] The dominant scattering processes and resulting transport features of graphene structures are very dependent on the range of the disorder potential and the robustness or destruction of the underlying sublattice symmetries....

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Journal ArticleDOI
TL;DR: In this article, a bilocal quark-quark operator connected by a straight Wilson line is proposed to study transverse momentum dependent parton distribution functions (TMDs) using lattice QCD.
Abstract: We discuss in detail a method to study transverse momentum dependent parton distribution functions (TMDs) using lattice QCD. To develop the formalism and to obtain first numerical results, we directly implement a bilocal quark-quark operator connected by a straight Wilson line, allowing us to study T-even, ''process-independent'' TMDs. Beyond results for x-integrated TMDs and quark densities, we present a study of correlations in x and k{sub perpendicular}. Our calculations are based on domain wall valence quark propagators by the LHP Collaboration calculated on top of gauge configurations provided by the MILC Collaboration with N{sub f}=2+1 asqtad-improved staggered sea quarks.

145 citations


Cites background or methods from "Phd by thesis"

  • ...As a side remark, we note that a simple correction model, the “taxi driver correction”, reduces the deviations particularly well in the unsmeared case [36]....

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  • ...The amplitudes Ãi in the limit η → ∞ can only depend on variables that are |η|-independent combinations of these invariants [36, 96]....

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  • ...6 We adjust our sign conventions for Ã9, Ã10 and Ã11 as well as the linear combination Ã9m ≡ Ã9 − 12m 2 N l (2)Ã11 with respect to previous work [34, 36] in favor of this simple correspondence....

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Journal ArticleDOI
TL;DR: Improved methods for isotopically labeling RNAs combined with new types of structural data obtained from a growing repertoire of NMR experiments are facilitating structural and dynamic studies of larger RNAs.
Abstract: Proper functioning of RNAs requires the formation of complex three-dimensional structures combined with the ability to rapidly interconvert between multiple functional states. This review covers recent advances in isotope-labeling strategies and NMR experimental approaches that have promise for facilitating solution structure determinations and dynamics studies of biologically active RNAs. Improved methods for the production of isotopically labeled RNAs combined with new multidimensional heteronuclear NMR experiments make it possible to dramatically reduce spectral crowding and simplify resonance assignments for RNAs. Several novel applications of experiments that directly detect hydrogen-bonding interactions are discussed. These studies demonstrate how NMR spectroscopy can be used to distinguish between possible secondary structures and identify mechanisms of ligand binding in RNAs. A variety of recently developed methods for measuring base and sugar residual dipolar couplings are described. NMR residual dipolar coupling techniques provide valuable data for determining the long-range structure and orientation of helical regions in RNAs. A number of studies are also presented where residual dipolar coupling constraints are used to determine the global structure and dynamics of RNAs. NMR relaxation data can be used to probe the dynamics of macromolecules in solution. The power dependence of transverse rotating-frame relaxation rates was used here to study dynamics in the minimal hammerhead ribozyme. Improved methods for isotopically labeling RNAs combined with new types of structural data obtained from a growing repertoire of NMR experiments are facilitating structural and dynamic studies of larger RNAs.

145 citations

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