7,377 research outputs found
Learning from Analysis of Japanese EFL Texts
Japan has a long tradition of teaching English as a foreign language (EFL). A common feature of EFL courses is reliance on specific textbooks as a basis for graded teaching, and periods in Japanese EFL history are marked by the introduction of different textbook series. These sets of textbooks share the common goal of taking students from beginners through to able English language users, so one would expect to find common characteristics across such series. As part of an on-going research programme in which Japanese EFL textbooks from different historical periods are compared and contrasted, we have recently focussed our efforts on using textual analysis tools to highlight distinctive characteristics of such textbooks. The present paper introduces one such analysis tool and describes some of the results from its application to three textbook series from distinct periods in Japanese EFL history. In so doing, we aim to encourage the use of textual analysis and seek to expose salient features of EFL texts which would likely remain hidden without such analytical techniques
Studying a relativistic field theory at finite chemical potential with the density matrix renormalization group
The density matrix renormalization group is applied to a relativistic complex
scalar field at finite chemical potential. The two-point function and various
bulk quantities are studied. It is seen that bulk quantities do not change with
the chemical potential until it is larger than the minimum excitation energy.
The technical limitations of the density matrix renormalization group for
treating bosons in relativistic field theories are discussed. Applications to
other relativistic models and to nontopological solitons are also suggested.Comment: 9 pages, 5 figures; v2: title changed; references added, conclusions
expanded, to be published in PR
The suppression of magnetism and the development of superconductivity within the collapsed tetragonal phase of Ca0.67Sr0.33Fe2As2 at high pressure
Structural and electronic characterization of (Ca0.67Sr0.33)Fe2As2 has been
performed as a func- tion of pressure up to 12 GPa using conventional and
designer diamond anvil cells. The compound (Ca0.67Sr0.33)Fe2As2 behaves
intermediate between its end members-CaFe2As2 and SrFe2As2- displaying a
suppression of magnetism and the onset of superconductivity. Like other members
of the AEFe2As2 family, (Ca0.67Sr0.33)Fe2As2 undergoes a pressure-induced
isostructural volume collapse, which we associate with the development of As-As
bonding across the mirror plane of the structure. This collapsed tetragonal
phase abruptly cuts off the magnetic state, giving rise to superconductivity
with a maximum Tc=22.2 K. The maximum Tc of the superconducting phase is not
strongly correlated with any structural parameter, but its proximity to the
abrupt suppression of magnetism as well as the volume collapse transition
suggests that magnetic interactions and structural inhomogeneity may play a
role in its development. The pressure-dependent evolution of the ordered states
and crystal structures in (Ca,Sr)Fe2As2 provides an avenue to understand the
generic behavior of the other members of the AEFe2As2 family.Comment: 9 pages, 9 figure
Genomic islands of divergence in the Yellow Tang and the Brushtail Tang Surgeonfishes.
The current ease of obtaining thousands of molecular markers challenges the notion that full phylogenetic concordance, as proposed by phylogenetic species concepts, is a requirement for defining species delimitations. Indeed, the presence of genomic islands of divergence, which may be the cause, or in some cases the consequence, of speciation, precludes concordance. Here, we explore this issue using thousands of RAD markers on two sister species of surgeonfishes (Teleostei: Acanthuridae), Zebrasoma flavescens and Z. scopas, and several populations within each species. Species are readily distinguished based on their colors (solid yellow and solid brown, respectively), yet populations and species are neither distinguishable using mitochondrial markers (cytochrome c oxidase 1), nor using 5193 SNPs (pairwise Φst = 0.034). In contrast, when using outlier loci, some of them presumably under selection, species delimitations, and strong population structure follow recognized taxonomic positions (pairwise Φst = 0.326). Species and population delimitation differences based on neutral and selected markers are likely due to local adaptation, thus being consistent with the idea that these genomic islands of divergence arose as a consequence of isolation. These findings, which are not unique, raise the question of a potentially important pathway of divergence based on local adaptation that is only evident when looking at thousands of loci
Gravitating Instantons In 3 Dimensions
We study the Einstein-Chern-Simons gravity coupled to Yang-Mills-Higgs theory
in three dimensional Euclidean space with cosmological constant. The classical
equations reduce to Bogomol'nyi type first order equations in curved space.
There are BPS type gauge theory instanton (monopole) solutions of finite action
in a gravitational instanton which itself has a finite action. We also discuss
gauge theory instantons in the vacuum (zero action) AdS space. In addition we
point out to some exact solutions which are singular.Comment: 17 pages, 4 figures, title has changed, gravitational instanton
actions are adde
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