The magnetic properties of 177^{\rm 177}Hf and 180^{\rm 180}Hf in the strong coupling deformed model

This paper reports NMR measurements of the magnetic dipole moments of two high-K isomers, the 37/2$^-$, 51.4 m, 2740 keV state in $^{\rm 177}$Hf and the 8$^-$, 5.5 h, 1142 keV state in $^{\rm 180}$Hf by the method of on-line nuclear orientation. Also included are results on the angular distributions of gamma transitions in the decay of the $^{\rm 177}$Hf isotope. These yield high precision E2/M1 multipole mixing ratios for transitions in bands built on the 23/2$^+$, 1.1 s, isomer at 1315 keV and on the 9/2$^+$, 0.663 ns, isomer at 321 keV. The new results are discussed in the light of the recently reported finding of systematic dependence of the behavior of the g$_{\rm R}$ parameter upon the quasi-proton and quasi-neutron make up of high-K isomeric states in this region.Comment: 9 pages, 9 figures, accepted for publication in Physical Review

On Conformal Infinity and Compactifications of the Minkowski Space

Using the standard Cayley transform and elementary tools it is reiterated that the conformal compactification of the Minkowski space involves not only the "cone at infinity" but also the 2-sphere that is at the base of this cone. We represent this 2-sphere by two additionally marked points on the Penrose diagram for the compactified Minkowski space. Lacks and omissions in the existing literature are described, Penrose diagrams are derived for both, simple compactification and its double covering space, which is discussed in some detail using both the U(2) approach and the exterior and Clifford algebra methods. Using the Hodge * operator twistors (i.e. vectors of the pseudo-Hermitian space H_{2,2}) are realized as spinors (i.e., vectors of a faithful irreducible representation of the even Clifford algebra) for the conformal group SO(4,2)/Z_2. Killing vector fields corresponding to the left action of U(2) on itself are explicitly calculated. Isotropic cones and corresponding projective quadrics in H_{p,q} are also discussed. Applications to flat conformal structures, including the normal Cartan connection and conformal development has been discussed in some detail.Comment: 38 pages, 8 figures, late

Remineralization of demineralized dentin using a dual analog system.

ObjectiveImproved methods are needed to remineralize dentin caries in order to promote conservation of dentin tissue and minimize the surgical interventions that are currently required for clinical treatment. Here, we test the hypothesis that bulk substrates can be effectively mineralized via a dual analog system proposed by others, using a tripolyphosphate (TPP) "templating analog" and a poly(acrylic acid) (PAA) or poly(aspartic acid) (pAsp) "sequestration analog," the latter of which generates the polymer-induced liquid-precursor (PILP) mineralization process studied in our laboratory.Material & methodsDemineralized human dentin slices were remineralized with and without pre-treatment with TPP, using either PAA or pAsp as the PILP process-directing agent. A control experiment with no polymer present was used for comparison.ResultsNo mineralization was observed in any of the PAA groups. In both the pAsp and no polymer groups, TPP inhibited mineralization on the surfaces of the specimens but promoted mineralization within the interiors. Pre-treatment with TPP enhanced overall mineralization of the pAsp group. However, when analysed via TEM, regions with little mineral were still present.ConclusionPoly(acrylic acid) was unable to remineralize demineralized dentin slices under the conditions employed, even when pre-treated with TPP. However, pre-treatment with TPP enhanced overall mineralization of specimens that were PILP-remineralized using pAsp

HATS-3b: An inflated hot Jupiter transiting an F-type star

We report the discovery by the HATSouth survey of HATS-3b, a transiting extrasolar planet orbiting a V=12.4 F-dwarf star. HATS-3b has a period of P = 3.5479d, mass of Mp = 1.07MJ, and radius of Rp = 1.38RJ. Given the radius of the planet, the brightness of the host star, and the stellar rotational velocity (vsini = 9.0km/s), this system will make an interesting target for future observations to measure the Rossiter-McLaughlin effect and determine its spin-orbit alignment. We detail the low/medium-resolution reconnaissance spectroscopy that we are now using to deal with large numbers of transiting planet candidates produced by the HATSouth survey. We show that this important step in discovering planets produces logg and Teff parameters at a precision suitable for efficient candidate vetting, as well as efficiently identifying stellar mass eclipsing binaries with radial velocity semi-amplitudes as low as 1 km/s.Comment: 11 pages, 10 figures, submitted to A

Quadratic solitons as nonlocal solitons

We show that quadratic solitons are equivalent to solitons of a nonlocal Kerr medium. This provides new physical insight into the properties of quadratic solitons, often believed to be equivalent to solitons of an effective saturable Kerr medium. The nonlocal analogy also allows for novel analytical solutions and the prediction of novel bound states of quadratic solitons.Comment: 4 pages, 3 figure

HATS-5b: A Transiting hot-Saturn from the HATSouth Survey

We report the discovery of HATS-5b, a transiting hot-Saturn orbiting a G type star, by the HAT-South survey. HATS-5b has a mass of Mp=0.24 Mj, radius of Rp=0.91 Rj, and transits its host star with a period of P=4.7634d. The radius of HATS-5b is consistent with both theoretical and empirical models. The host star has a V band magnitude of 12.6, mass of 0.94 Msun, and radius of 0.87 Rsun. The relatively high scale height of HATS-5b, and the bright, photometrically quiet host star, make this planet a favourable target for future transmission spectroscopy follow-up observations. We reexamine the correlations in radius, equilibrium temperature, and metallicity of the close-in gas-giants, and find hot Jupiter-mass planets to exhibit the strongest dependence between radius and equilibrium temperature. We find no significant dependence in radius and metallicity for the close-in gas-giant population.Comment: 10 pages, submitted to A

Fermionic coherent states for pseudo-Hermitian two-level systems

We introduce creation and annihilation operators of pseudo-Hermitian fermions for two-level systems described by pseudo-Hermitian Hamiltonian with real eigenvalues. This allows the generalization of the fermionic coherent states approach to such systems. Pseudo-fermionic coherent states are constructed as eigenstates of two pseudo-fermion annihilation operators. These coherent states form a bi-normal and bi-overcomplete system, and their evolution governed by the pseudo-Hermitian Hamiltonian is temporally stable. In terms of the introduced pseudo-fermion operators the two-level system' Hamiltonian takes a factorized form similar to that of a harmonic oscillator.Comment: 13 pages (Latex, article class), no figures; v2: some amendments in section 2, seven new refs adde

HATS-1b: The First Transiting Planet Discovered by the HATSouth Survey

We report the discovery of HATS-1b, a transiting extrasolar planet orbiting the moderately bright V=12.05 G dwarf star GSC 6652-00186, and the first planet discovered by HATSouth, a global network of autonomous wide-field telescopes. HATS-1b has a period P~3.4465 d, mass Mp~1.86MJ, and radius Rp~1.30RJ. The host star has a mass of 0.99Msun, and radius of 1.04Rsun. The discovery light curve of HATS-1b has near continuous coverage over several multi-day periods, demonstrating the power of using a global network of telescopes to discover transiting planets.Comment: Submitted to AJ 10 pages, 5 figures, 6 table

HL-1 cells express an inwardly rectifying K+ current activated via muscarinic receptors comparable to that in mouse atrial myocytes

An inwardly rectifying K^+ current is present in atrial cardiac myocytes that is activated by acetylcholine (I_{KACh}). Physiologically, activation of the current in the SA node is important in slowing the heart rate with increased parasympathetic tone. It is a paradigm for the direct regulation of signaling effectors by the Gβγ G-protein subunit. Many questions have been addressed in heterologous expression systems with less focus on the behaviour in native myocytes partly because of the technical difficulties in undertaking comparable studies in native cells. In this study, we characterise a potassium current in the atrial-derived cell line HL-1. Using an electrophysiological approach, we compare the characteristics of the potassium current with those in native atrial cells and in a HEK cell line expressing the cloned Kir3.1/3.4 channel. The potassium current recorded in HL-1 is inwardly rectifying and activated by the muscarinic agonist carbachol. Carbachol-activated currents were inhibited by pertussis toxin and tertiapin-Q. The basal current was time-dependently increased when GTP was substituted in the patch-clamp pipette by the non-hydrolysable analogue GTPγS. We compared the kinetics of current modulation in HL-1 with those of freshly isolated atrial mouse cardiomyocytes. The current activation and deactivation kinetics in HL-1 cells are comparable to those measured in atrial cardiomyocytes. Using immunofluorescence, we found GIRK4 at the membrane in HL-1 cells. Real-time RT-PCR confirms the presence of mRNA for the main G-protein subunits, as well as for M2 muscarinic and A1 adenosine receptors. The data suggest HL-1 cells are a good model to study IKAch

Unresolved issues and new challenges in teaching English to young learners:the case of South Korea

The introduction of languages, especially English, into the primary curriculum around the world has been one of the major language-in-education policy developments in recent years. In countries where English has been compulsory for a number of years, the question arises as to what extent the numerous and well-documented challenges faced by the initial implementation of early language learning policies have been overcome and whether new challenges have arisen as policies have become consolidated. This article therefore focuses on South Korea, where English has been compulsory in primary school since 1997. The issues raised by the introduction of English into the primary curriculum are reviewed and the current situation in South Korea is investigated. The results of a mixed methods study using survey data from 125 Korean primary school teachers, together with data from a small-scale case study of one teacher are presented. The study shows that, while some of the initial problems caused by the introduction of early language learning appear to have been addressed, other challenges persist. Moreover, the data reveal the emergence of a number of new challenges faced by primary school teachers of English as they seek to implement government policy