4,681 research outputs found
The social, political and economic influences of the Edinburgh merchant elite, 1600-1638.
2 volsSIGLEAvailable from British Library Document Supply Centre- DSC:D67130/86 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Thermal history of the early Miocene Waitemata Basin and adjacent Waipapa Group, North Island, New Zealand
Apatite fission track (AFT) and vitrinite reflectance (VR) data for early Miocene outcrops from the Waitemata Basin reveal that the basin sequence was subjected to shallow burial before denudation. AFT results suggest that the total sediment thickness within the basin was <=1 km and maximum paleotemperatures during burial never exceeded c. 60deg.C. Statistical analyses of the detrital AFT ages distinguish four dominant sources of sediment supply: contemporaneous volcanism; metagreywacke rocks of the Waipapa Group; the Northland Allochthon; and an unidentified source south of the basin.
The apatite and zircon fission track results from the Waipapa Group rocks (Gondwana Terrane) adjacent to the basin suggest two discrete phases of accelerated cooling: the first during the early Cretaceous (c. 117 Ma) and the second during the mid Cretaceous (c. 84 Ma). These events probably reflect key stages in the tectonic development of the New Zealand microcontinent during the Cretaceous period, the earlier event being related to the climax of compressional deformation (Rangitata Orogeny) and the latter to extensional tectonism associated with the opening of the Tasman Sea. Waipapa Group rocks now exposed at the surface cooled from maximum paleotemperatures of c. 250deg.C at an estimated rate of c. 180-36deg.C/m.y., involving substantial denudation
Connected (graded) Hopf algebras
We study algebraic and homological properties of two classes of
infinite dimensional Hopf algebras over an algebraically closed field k of characteristic zero. The first class consists of those Hopf k-algebras that are connected
graded as algebras, and the second class are those Hopf k-algebras that are
connected as coalgebras. For many but not all of the results presented here,
the Hopf algebras are assumed to have finite Gel'fand-Kirillov dimension. It
is shown that if the Hopf algebra H is a connected graded Hopf algebra of
finite Gel'fand-Kirillov dimension n, then H is a noetherian domain which is
Cohen-Macaulay, Artin-Schelter regular and Auslander regular of global dimension n. It has S2 = IdH, and is Calabi-Yau. Detailed information is also
provided about the Hilbert series of H. Our results leave open the possibility
that the first class of algebras is (properly) contained in the second. For this
second class, the Hopf k-algebras of finite Gel'fand-Kirillov dimension n with
connected coalgebra, the underlying coalgebra is shown to be Artin-Schelter
regular of global dimension n. Both these classes of Hopf algebra share many
features in common with enveloping algebras of finite dimensional Lie algebras. For example, an algebra in either of these classes satisfies a polynomial identity
only if it is a commutative polynomial algebra. Nevertheless, we construct, as
one of our main results, an example of a Hopf k-algebra H of Gel'fand-Kirillov
dimension 5, which is connected graded as an algebra and connected as a
coalgebra, but is not isomorphic as an algebra to U(g) for any Lie algebra g
Decay of flux vacua to nothing
We construct instanton solutions describing the decay of flux
compactifications of a gauge theory by generalizing the Kaluza-Klein
bubble of nothing. The surface of the bubble is described by a smooth
magnetically charged solitonic brane whose asymptotic flux is precisely that
responsible for stabilizing the 4d compactification. We describe several
instances of bubble geometries for the various vacua occurring in a
Einstein-Maxwell theory namely, AdS_4 x S^2, R^{1,3} x S^2, and dS_4 x S^2.
Unlike conventional solutions, the bubbles of nothing introduced here occur
where a {\em two}-sphere compactification manifold homogeneously degenerates.Comment: 31 pages, 15 figure
Retrospective Reports of Childhood Trauma in Adults with ADHD
Although studies have documented higher prevalence of abuse in children with ADHD, no studies have investigated
childhood reports of abuse in individuals identified withADHDin adulthood. Method: FortyADHDwomen, 17ADHD
males, 17 female controls, and 40 male controls complete the Childhood Trauma Questionnaire and other measures of
psychosocial functioning. Results: Emotional abuse and neglect are more common among men and women with ADHD as
compared to controls. Sexual abuse and physical neglect are more commonly reported by females with ADHD. Although
childhood abuse is significantly correlated with depression and anxiety in adulthood, having ADHD is a better predictor of
poorer psychosocial functioning in adulthood. Conclusion: Clinicians are alerted that patients with ADHD symptoms have a
high probability of childhood abuse
Pencil-Beam Surveys for Trans-Neptunian Objects: Limits on Distant Populations
Two populations of minor bodies in the outer Solar System remain particularly
elusive: Scattered Disk objects and Sedna-like objects. These populations are
important dynamical tracers, and understanding the details of their spatial-
and size-distributions will enhance our understanding of the formation and
on-going evolution of the Solar System. By using newly-derived limits on the
maximum heliocentric distances that recent pencil-beam surveys for
Trans-Neptunian Objects were sensitive to, we determine new upper limits on the
total numbers of distant SDOs and Sedna-like objects. While generally
consistent with populations estimated from wide-area surveys, we show that for
magnitude-distribution slopes of {\alpha} > 0.7-1.0, these pencil-beam surveys
provide stronger upper limits than current estimates in literature.Comment: Submitted to Icaru
Theory of Melting and the Optical Properties of Gold/DNA Nanocomposites
We describe a simple model for the melting and optical properties of a
DNA/gold nanoparticle aggregate. The optical properties at fixed wavelength
change dramatically at the melting transition, which is found to be higher and
narrower in temperature for larger particles, and much sharper than that of an
isolated DNA link. All these features are in agreement with available
experiments. The aggregate is modeled as a cluster of gold nanoparticles on a
periodic lattice connected by DNA bonds, and the extinction coefficient is
computed using the discrete dipole approximation. Melting takes place as an
increasing number of these bonds break with increasing temperature. The melting
temperature corresponds approximately to the bond percolation threshold.Comment: 5 pages, 4 figure. To be published in Phys. Rev.
Modelling of Tirapazamine effects on solid tumour morphology
Bioreductive drugs are in clinical practice to exploit the resistance from tumour microenvironments especially in the hypoxic region of tumour. We pre-sented a tumour treatment model to capture the pharmacology of one of the most prominent bioreductive drugs, Tirapazamine (TPZ) which is in clinical trials I and II. We calculated solid tumour mass in our previous work and then integrated that model with TPZ infusion. We calculated TPZ cytotoxicity, concentration, penetra-tion with increasing distance from blood vessel and offered resistance from micro-environments for drug penetration inside the tumour while considering each cell as an individual entity. The impact of these factors on tumour morphology is also showed to see the drug behaviour inside animals/humans tumours. We maintained the heterogeneity factors in presented model as observed in real tumour mass es-pecially in terms of cells proliferation, cell movement, extracellular matrix (ECM) interaction, and the gradients of partial oxygen pressure (pO2) inside tumour cells during the whole growth and treatment activity. The results suggest that TPZ high concentration in combination with chemotherapy should be given to get maximum abnormal cell killing. This model can be a good choice for oncologists and re-searchers to explore more about TPZ action inside solid tumour
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