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Petrography and bulk composition of Miller Range 05035: a new lunar VLT gabbro
Miller Range (MIL) 05035 is a crystalline lunar mare gabbroic meteorite collected in Antarctica in 2005 [1]. It is an important new sample in the lunar meteorite (LM) collection as it is only one of ~8 to be classified as basaltic in nature. MIL 05035 is coarsely grained with large pyroxene grains ( 8mm) subophitically enclosing plagioclase grains ( 6mm), and accessory ilmenite, spinel, silica and sulphide phases
Flat-top oscillons in an expanding universe
Oscillons are extremely long lived, oscillatory, spatially localized field
configurations that arise from generic initial conditions in a large number of
non-linear field theories. With an eye towards their cosmological implications,
we investigate their properties in an expanding universe. We (1) provide an
analytic solution for one dimensional oscillons (for the models under
consideration) and discuss their generalization to 3 dimensions, (2) discuss
their stability against long wavelength perturbations and (3) estimate the
effects of expansion on their shapes and life-times. In particular, we discuss
a new, extended class of oscillons with surprisingly flat tops. We show that
these flat topped oscillons are more robust against collapse instabilities in
(3+1) dimensions than their usual counterparts. Unlike the solutions found in
the small amplitude analysis, the width of these configurations is a
non-monotonic function of their amplitudes.Comment: v2-matches version published in Phys. Rev D. Updated references and
minor modification to section 4.
On the Optical -- X-ray correlation from outburst to quiescence in Low Mass X-ray Binaries: the representative cases of V404 Cyg and Cen X-4
Low mass X-ray binaries (LMXBs) show evidence of a global correlation of
debated origin between X-ray and optical luminosity. We study for the first
time this correlation in two transient LMXBs, the black hole V404 Cyg and the
neutron star Cen X-4, over 6 orders of magnitude in X-ray luminosity, from
outburst to quiescence. After subtracting the contribution from the companion
star, the Cen X-4 data can be described by a single power law correlation of
the form , consistent with disk reprocessing. We
find a similar correlation slope for V404 Cyg in quiescence (0.46) and a
steeper one (0.56) in the outburst hard state of 1989. However, V404 Cyg is
about times optically brighter, at a given keV X-ray
luminosity, compared to Cen X-4. This ratio is a factor of 10 smaller in
quiescence, where the normalization of the V404 Cyg correlation also changes.
We show that once the bolometric X-ray emission is considered and the known
main differences between V404 Cyg and Cen X-4 are taken into account (a larger
compact object mass, accretion disk size, and the presence of a strong jet
contribution in the hard state for the black hole system) the two systems lie
on the same correlation. In V404 Cyg, the jet dominates spectrally at
optical-infrared frequencies during the hard state, but makes a negligible
contribution in quiescence, which may account for the change in its correlation
slope and normalization. These results provide a benchmark to compare with data
from the 2015 outburst of V404 Cyg and, potentially, other transient LMXBs as
well.Comment: Accepted on ApJ, 12 pages, 4 figures, 4 table
Results of the Mariner 6 and 7 Mars occultation experiments
Final profiles of temperature, pressure, and electron density on Mars were obtained for the Mariner 6 and 7 entry and exit cases, and results are presented for both the lower atmosphere and ionosphere. The results of an analysis of the systematic and formal errors introduced at each stage of the data-reduction process are also included. At all four occulation points, the lapse rate of temperature was subdadiabatic up to altitudes in excess of 20 km. A pronounced temperature inversion was present above the surface at the Mariner 6 exit point. All four profiles exhibit a sharp, superadiabatic drop in temperature at high altitudes, with temperatures falling below the frost point of CO2. These results give a strong indication of frozen CO2 in the middle atmosphere of Mars
Comment on "Control landscapes are almost always trap free: a geometric assessment"
We analyze a recent claim that almost all closed, finite dimensional quantum
systems have trap-free (i.e., free from local optima) landscapes (B. Russell
et.al. J. Phys. A: Math. Theor. 50, 205302 (2017)). We point out several errors
in the proof which compromise the authors' conclusion.
Interested readers are highly encouraged to take a look at the "rebuttal"
(see Ref. [1]) of this comment published by the authors of the criticized work.
This "rebuttal" is a showcase of the way the erroneous and misleading
statements under discussion will be wrapped up and injected in their future
works, such as R. L. Kosut et.al, arXiv:1810.04362 [quant-ph] (2018).Comment: 6 pages, 1 figur
Repetitive Segmental Structure of the Transducin β Subunit: Homology with the CDC4 Gene and Identification of Related mRNAs
Retinal transducin, a guanine nucleotide regulatory protein (referred to as a G protein) that activates a cGMP phosphodiesterase in photoreceptor cells, is comprised of three subunits. We have identified and analyzed cDNA clones of the bovine transducin β subunit that may be highly conserved or identical to that in other G proteins. From the cDNA nucleotide sequence of the entire coding region, the primary structure of a 340-amino acid protein was deduced. The encoded β subunit has a Mr of 37,375 and is comprised of repetitive homologous segments arranged in tandem. Furthermore, significant homology in primary structure and segmental sequence exists between the β subunit and the yeast CDC4 gene product. The Mr 37,375 β subunit polypeptide is encoded by a 2.9-kilobase (kb) mRNA. However, there exists in retina other β-related mRNAs that are divergent from the 2.9-kb mRNA on the basis of oligonucleotide and primer-extended probe hybridizations. All mammalian tissues and clonal cell lines that have been examined contain at least two β-related mRNAs, usually 1.8 and 2.9 kb in length. These results suggest that the mRNAs are the processed products of a small number of closely related genes or of a single highly complex β gene
Magnetized Turbulent Dynamo in Protogalaxies
The prevailing theory for the origin of cosmic magnetic fields is that they
have been amplified to their present values by the turbulent dynamo inductive
action in the protogalactic and galactic medium. Up to now, in calculation of
the turbulent dynamo, it has been customary to assume that there is no back
reaction of the magnetic field on the turbulence, as long as the magnetic
energy is less than the turbulent kinetic energy. This assumption leads to the
kinematic dynamo theory. However, the applicability of this theory to
protogalaxies is rather limited. The reason is that in protogalaxies the
temperature is very high, and the viscosity is dominated by magnetized ions. As
the magnetic field strength grows in time, the ion cyclotron time becomes
shorter than the ion collision time, and the plasma becomes strongly
magnetized. As a result, the ion viscosity becomes the Braginskii viscosity.
Thus, in protogalaxies the back reaction sets in much earlier, at field
strengths much lower than those which correspond to field-turbulence energy
equipartition, and the turbulent dynamo becomes what we call the magnetized
turbulent dynamo. In this paper we lay the theoretical groundwork for the
magnetized turbulent dynamo. In particular, we predict that the magnetic energy
growth rate in the magnetized dynamo theory is up to ten time larger than that
in the kinematic dynamo theory. We also briefly discuss how the Braginskii
viscosity can aid the development of the inverse cascade of magnetic energy
after the energy equipartition is reached.Comment: accepted to ApJ, 35 pages, 3 figure
A tri-dimensional approach for auditing brand loyalty
Over the past twenty years brand loyalty has been an important topic for both marketing practitioners and academics. While practitioners have produced proprietary brand loyalty audit models, there has been little academic research to make transparent the methodology that underpins these audits and to enable practitioners to understand, develop and conduct their own audits. In this paper, we propose a framework for a brand loyalty audit that uses a tri-dimensional approach to brand loyalty, which includes behavioural loyalty and the two components of attitudinal loyalty: emotional and cognitive loyalty. In allowing for different levels and intensity of brand loyalty, this tri-dimensional approach is important from a managerial perspective. It means that loyalty strategies that arise from a brand audit can be made more effective by targeting the market segments that demonstrate the most appropriate combination of brand loyalty components. We propose a matrix with three dimensions (emotional, cognitive and behavioural loyalty) and two levels (high and low loyalty) to facilitate a brand loyalty audit. To demonstrate this matrix, we use the example of financial services, in particular a rewards-based credit card
Magnetic reconnection with anomalous resistivity in two-and-a-half dimensions I: Quasi-stationary case
In this paper quasi-stationary, two-and-a-half-dimensional magnetic
reconnection is studied in the framework of incompressible resistive
magnetohydrodynamics (MHD). A new theoretical approach for calculation of the
reconnection rate is presented. This approach is based on local analytical
derivations in a thin reconnection layer, and it is applicable to the case when
resistivity is anomalous and is an arbitrary function of the electric current
and the spatial coordinates. It is found that a quasi-stationary reconnection
rate is fully determined by a particular functional form of the anomalous
resistivity and by the local configuration of the magnetic field just outside
the reconnection layer. It is also found that in the special case of constant
resistivity reconnection is Sweet-Parker and not Petschek.Comment: 15 pages, 4 figures, minor changes as compared to the 1st versio
Bringing Agroforestry Technology to Farmers in the Philippines: Identifying constraints to success using systems modelling
Bayesian Belief Network (BBN) modelling may be applied in rural extension in situations where program outputs are influenced by variables which are sequentially influenced by other variables. For a recently completed agroforestry extension program in Leyte the Philippines, BBN modelling of site factors, establishment practices and risk, predicted widely different program outputs for different levels of extension assistance and farmer inputs. In a situation where very little was known about how farmers would respond to offers of extension assistance, monitoring of the program over a period of three years revealed that extended extension assistance was crucial in determining the likely survival and growth of trees. Extended extension assistance was also important for the elimination of unsuitable sites and the use of appropriate establishment procedures. Where extension support was not available, farmers displayed a poor knowledge of the principles of tree growth, planting trees underneath complete canopies and adjacent to mature coconut palms even though they could have been expected to have extensive local knowledge of raising and growing plants. Approximately one third of planting sites were infertile and eroded and growth of newly planted trees on these sites was poor, often because site preparation and maintenance was minimal. Newly established trees were also found to be at risk from fire, typhoon, and grazing and in situations where plantations were destroyed, farmers became antagonistic towards the program. The implications of the BBN modelling for a hypothetically expanded program are that extended assistance and site inspections are necessary to eliminate planting trees on inappropriate and unsuitable sites and to improve establishment practices and weed control in order to avoid plantations of suppressed and chlorotic trees which fail to meet the expectations of farmers, thus impinging on the success of the program
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