5,916 research outputs found
First-year composition and transfer: a quantitative study
The present study investigated the effect of writing pedagogy on transfer by examining the effect of pedagogical orientation (WAC/WID or ‘traditional’) on content-area grades. Participants were 1,052 undergraduates from 17 schools throughout the United States. Hypothesis was that the WAC/WID orientation would lead to higher transfer levels as measured by participants’ higher content-area performance. Composition grades were collected in year one; content-area grades where collected in year two. Propensity scores were calculated to stratify the groups and minimize selection bias of writing-class assignment, thereby allowing quasi-causal inference. An ANOVA was performed on the resulting 2-by-5 stratified data. Results indicated that students who completed the WAC/WID composition classes received significantly higher content grades than those in the ‘traditional’ writing classes. The results confirmed the hypothesis
How Can We Obtain a Large Majorana-Mass in Calabi-Yau Models ?
In a certain type of Calabi-Yau superstring models it is clarified that the
symmetry breaking occurs by stages at two large intermediate energy scales and
that two large intermediate scales induce large Majorana-masses of right-handed
neutrinos. Peculiar structure of the effective nonrenormalizable interactions
is crucial in the models. In this scheme Majorana-masses possibly amount to
O(10^{9 \sim 10}\gev) and see-saw mechanism is at work for neutrinos. Based
on this scheme we propose a viable model which explains the smallness of masses
for three kind of neutrinos .
Special forms of the nonrenormalizable interactions can be understood as a
consequence of an appropriate discrete symmetry of the compactified manifold.Comment: 30-pages + 6-figures, LaTeX, Preprint DPNU-94-02, AUE-01-9
Transition density of diffusion on Sierpinski gasket and extension of Flory's formula
Some problems related to the transition density u(t,x) of the diffusion on
the Sierpinski gasket are considerd, based on recent rigorous results and
detailed numerical calculations. The main contents are an extension of Flory's
formula for the end-to-end distance exponent of self-avoiding walks on the
fractal spaces, and an evidence of the oscillatory behavior of u(t,x) on the
Sierpinski gasket.Comment: 11 pages, REVTEX, 2 postscript figure
Complete Genome Sequences of Arcobacter butzleri ED-1 and Arcobacter sp Strain L, Both Isolated from a Microbial Fuel Cell
Arcobacter butzleri strain ED-1 is an exoelectrogenic epsilonproteobacterium isolated from the anode biofilm of a microbial fuel cell. Arcobacter sp. strain L dominates the liquid phase of the same fuel cell. Here we report the finished and annotated genome sequences of these organisms
Topology, Hidden Spectra and Bose Einstein Condensation on low dimensional complex networks
Topological inhomogeneity gives rise to spectral anomalies that can induce
Bose-Einstein Condensation (BEC) in low dimensional systems. These anomalies
consist in energy regions composed of an infinite number of states with
vanishing weight in the thermodynamic limit (hidden states). Here we present a
rigorous result giving the most general conditions for BEC on complex networks.
We prove that the presence of hidden states in the lowest region of the
spectrum is the necessary and sufficient condition for condensation in low
dimension (spectral dimension ), while it is shown that BEC
always occurs for .Comment: 4 pages, 10 figure
Manifestations of fine features of the density of states in the transport properties of KOs2O6
We performed high-pressure transport measurements on high-quality single
crystals of KOs2O6, a beta-pyrochlore superconductor. While the resistivity at
high temperatures might approach saturation, there is no sign of saturation at
low temperatures, down to the superconducting phase. The anomalous resistivity
is accompanied by a nonmetallic behavior in the thermoelectric power (TEP) up
to temperatures of at least 700 K, which also exhibits a broad hump with a
maximum at 60 K. The pressure influences mostly the low-energy electronic
excitations. A simple band model based on enhanced density of states in a
narrow window around the Fermi energy (EF) explains the main features of this
unconventional behavior in the transport coefficients and its evolution under
pressure
Emergent QCD Kondo effect in two-flavor color superconducting phase
We show that effective coupling strengths between ungapped and gapped quarks
in the two-flavor color superconducting (2SC) phase are renormalized by
logarithmic quantum corrections. We obtain a set of coupled
renormalization-group (RG) equations for two distinct effective coupling
strengths arising from gluon exchanges carrying different color charges. The
diagram of RG flow suggests that both of the coupling strengths evolve into a
strong-coupling regime as we decrease the energy scale toward the Fermi
surface. This is a characteristic behavior observed in the Kondo effect, which
has been known to occur in the presence of impurity scatterings via non-Abelian
interactions. We propose a novel Kondo effect emerging without doped
impurities, but with the gapped quasiexcitations and the residual SU(2) color
subgroup intrinsic in the 2SC phase, which we call the 2SC Kondo effect.Comment: Discussions added before the conclusion. Published versio
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