Intrusive origin of the Sudbury Igneous Complex: Structural and sedimentological evidence

In recent years, many geoscientists have come to believe that the Sudbury event was exogenic rather than endogenic. Critical to a recent exogenic hypothesis is the impact melt origin of the Sudbury Igneous Complex (SIC). Such origin implies that the SIC was emplaced before deposition of the Whitewater Group, in contrast to origins in which the SIC postdates the lithification of the Onaping Formation. Structural and sedimentological evidence is summarized herein that supports an intrusion of the SIC after lithification of all Whitewater Group strata, and conflicts with the hypothesis advanced by other researchers

A New Generating Function for Calculating the Igusa Local Zeta Function

A new method is devised for calculating the Igusa local zeta function $Z_f$ of a polynomial $f(x_1,\dots,x_n)$ over a $p$-adic field. This involves a new kind of generating function $G_f$ that is the projective limit of a family of generating functions, and contains more data than $Z_f$. This $G_f$ resides in an algebra whose structure is naturally compatible with operations on the underlying polynomials, facilitating calculation of local zeta functions. This new technique is used to expand significantly the set of quadratic polynomials whose local zeta functions have been calculated explicitly. Local zeta functions for arbitrary quadratic polynomials over $p$-adic fields with $p$ odd are presented, as well as for polynomials over unramified $2$-adic fields of the form $Q+L$ where $Q$ is a quadratic form and $L$ is a linear form where $Q$ and $L$ have disjoint variables. For a quadratic form over an arbitrary $p$-adic field with odd $p$, this new technique makes clear precisely which of the three candidate poles are actual poles.Comment: 54 page

The forests of Kalimpong : an ecological account

Although the vegetation of Sikkim is as well known as that of any part of India, comparatively little attention has been paid to the area now known as the Kaiimpong Sub -Division of the Darjeeling District.The territory, though originally part of the Sikkim state, was annexed by the Bhutanese in 1706 and until 1865 it remained in their hands. Under the Senchula Treaty of 1865 it became part of British India and was added to the Darjeeling District. Although both Sikkim and Bhutah were explored by Dr. Griffith and Sir Joseph Hooker early in the nineteenth century, little attention was paid to this area.The most complete accont of the vegetation of Kalimpong which has hitherto been written was published by the late Mr. J.S.Gamble in the Indian Forester in 1875, in an article entitled "Darjeeling Forests ", and yet in this article Mr. Gamble describes the area east of the Tista, which is the Kalimpong Sub -Division, as "practically unexplored ". Before leaving the District finally in 1882 Mr. Gamble had visited a considerable part of this area and noted the prevalence of certain plants in various - localities. These he recorded in his "List of the - Trees, Shrubs and Climbers of the Darjeeling District.Uf subsequent publications relating to Darjeeling or Sikkim the most important have dealt with the Alpine Flora of tue higher levels in - Sikkim proper or with plants of a particular family only. Nothing more than notes of cursory tours in this area have appeared. The District is included in the Flora of British India but not in Prain's Bengal Plants, and for many years Gamble's List has been the only convenient Forest Flora of the District. This List was revised by myself and my wife in 1925 and is now being published under the title "The 'frees of Northern Bengal:'Altogether Three Forest Working Plans for the Kalimpong Forest Division have been published. The Third Working Plan was published by myself in 1924 and is the only plan which contains a detailed description of the forests. The data given in the present work were collected mainly from 1922 -1924 during the preparation of the Third Forest Working - Plan and part of the material has already been published in a different form in the Plan itself. It has now been supplemented by further observations made in 1926 and it is believed that the account of the forest climax communities is fairly complete although much work still remains to be done before our knowledge of the herbaceous communities reaches the same standard. The study of the cryptogamic plants has only just been begun

Improved V II log(gfgf) Values, Hyperfine Structure Constants, and Abundance Determinations in the Photospheres of the Sun and Metal-poor Star HD 84937

New experimental absolute atomic transition probabilities are reported for 203 lines of V II. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The branching fractions are normalized with radiative lifetime measurements to determine the new transition probabilities. Generally good agreement is found between this work and previously reported V II transition probabilities. Use of two spectrometers, independent radiometric calibration methods, and independent data analysis routines enables a reduction in systematic uncertainties, in particular those due to optical depth errors. In addition, new hyperfine structure constants are measured for selected levels by least squares fitting line profiles in the FTS spectra. The new V II data are applied to high resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to determine new, more accurate V abundances. Lines covering a range of wavelength and excitation potential are used to search for non-LTE effects. Very good agreement is found between our new solar photospheric V abundance, log {\epsilon}(V) = 3.95 from 15 V II lines, and the solar-system meteoritic value. In HD 84937, we derive [V/H] = -2.08 from 68 lines, leading to a value of [V/Fe] = 0.24.Comment: 32 pages, 7 tables (3 machine-readable), 8 figures; accepted for publication in ApJ

Theoretical study of resonant x-ray emission spectroscopy of Mn films on Ag

We report a theoretical study on resonant x-ray emission spectra (RXES) in the whole energy region of the Mn $L_{2,3}$ white lines for three prototypical Mn/Ag(001) systems: (i) a Mn impurity in Ag, (ii) an adsorbed Mn monolayer on Ag, and (iii) a thick Mn film. The calculated RXES spectra depend strongly on the excitation energy. At $L_3$ excitation, the spectra of all three systems are dominated by the elastic peak. For excitation energies around $L_2$, and between $L_3$ and $L_2$, however, most of the spectral weight comes from inelastic x-ray scattering. The line shape of these inelastic ``satellite'' structures changes considerably between the three considered Mn/Ag systems, a fact that may be attributed to changes in the bonding nature of the Mn-$d$ orbitals. The system-dependence of the RXES spectrum is thus found to be much stronger than that of the corresponding absorption spectrum. Our results suggest that RXES in the Mn $L_{2,3}$ region may be used as a sensitive probe of the local environment of Mn atoms.Comment: 9 pages, 11 figure

Walking dynamics are symmetric (enough)

Many biological phenomena such as locomotion, circadian cycles, and breathing are rhythmic in nature and can be modeled as rhythmic dynamical systems. Dynamical systems modeling often involves neglecting certain characteristics of a physical system as a modeling convenience. For example, human locomotion is frequently treated as symmetric about the sagittal plane. In this work, we test this assumption by examining human walking dynamics around the steady-state (limit-cycle). Here we adapt statistical cross validation in order to examine whether there are statistically significant asymmetries, and even if so, test the consequences of assuming bilateral symmetry anyway. Indeed, we identify significant asymmetries in the dynamics of human walking, but nevertheless show that ignoring these asymmetries results in a more consistent and predictive model. In general, neglecting evident characteristics of a system can be more than a modeling convenience---it can produce a better model.Comment: Draft submitted to Journal of the Royal Society Interfac