title:
A New Six Degree-of-Freedom Haptic Device based on the Orthoglide and
  the Agile Eye

abstract:
  The aim of this paper is to present a new six degree-of-freedom (dof) haptic
device using two parallel mechanisms. The first one, called orthoglide,
provides the translation motions and the second one produces the rotational
motions. These two motions are decoupled to simplify the direct and inverse
kinematics, as it is needed for real-times control. To reduce the inertial
load, the motors are fixed on the base and a transmission with two universal
joints is used to transmit the rotational motions from the base to the
end-effector. The main feature of the orthoglide and of the agile eye mechanism
is the existence of an isotropic configuration. The length of the legs and the
range limits of the orthoglide are optimized to have homogeneous performance
throughout the Cartesian workspace, which has a nearly cubic workspace. These
properties permit to have a high stiffness throughout the workspace and
workspace limits that are easily understandable by the user.


title:
KCrF_3: Electronic Structure, Magnetic and Orbital Ordering from First
  Principles

abstract:
  The electronic, magnetic and orbital structures of KCrF_3 are determined in
all its recently identified crystallographic phases (cubic, tetragonal, and
monoclinic) with a set of {\it ab initio} LSDA and LSDA+U calculations. The
high-temperature undistorted cubic phase is metallic within the LSDA, but at
the LSDA+U level it is a Mott insulator with a gap of 1.72 eV. The tetragonal
and monoclinic phases of KCrF_3 exhibit cooperative Jahn-Teller distortions
concomitant with staggered 3x^2-r^2/3y^2-r^2 orbital order. We find that the
energy gain due to the Jahn-Teller distortion is 82/104 meV per chromium ion in
the tetragonal/monoclinic phase, respectively. These phases show A-type
magnetic ordering and have a bandgap of 2.48 eV. In this Mott insulating state
KCrF_3 has a substantial conduction bandwidth of 2.1 eV, leading to the
possibility for the kinetic energy of charge carriers in electron- or
hole-doped derivatives of KCrF_3 to overcome the polaron localization at low
temperatures, in analogy with the situation encountered in the colossal
magnetoresistive manganites.


title: Renault's Equivalence Theorem for Groupoid Crossed Products

abstract:
  We provide an exposition and proof of Renault's equivalence theorem for
crossed products by locally Hausdorff, locally compact groupoids. Our approach
stresses the bundle approach, concrete imprimitivity bimodules and is a
preamble to a detailed treatment of the Brauer semigroup for a locally
Hausdorff, locally compact groupoid.


title:
Automatizing the application of Mellin-Barnes representations for
  Feynman integrals

abstract:
  Feynman diagrams may be evaluated by Mellin-Barnes representations of their
Feynman parameter integrals in d=4-2\eps dimensions. Recently, the Mathematica
toolkit AMBRE has been developed for the automatic derivation of such
representations with a loop-by-loop approach. We describe the package and
exemplify its use with the \eps-expansion of the massive one-loop QED vertex
function.


title: ALICE Detector Status and Commissioning

abstract:
  The Large Hadron Collider (LHC) will start operation in the end of 2007
colliding proton and lead beams at \surd S = 14 TeV and \surd S_{NN} = 5.5 TeV,
respectively. The accelerator and the experiments are under construction and
detailed studies of the physics program are being prepared. I will in this
paper review the current status of the ALICE experiment and the heavy ion
physics aspects that are unique at LHC.


title:
Transport through a double barrier in Large Radius Carbon Nanotubes in
  the presence of a transverse magnetic field

abstract:
  We discuss the Luttinger Liquid behaviour of Large Radius Carbon Nanotube
e.g. the Multi Wall ones (MWNT), under the action of a transverse magnetic
field $B$. Our results imply a reduction with $B$ in the value of the $bulk$
critical exponent, $\alpha_{bulk}$, for the tunneling density of states, which
is in agreement with that observed in transport experiments. Then, the problem
of the transport through a Quantum Dot formed by two intramolecular tunneling
barriers along the MWNT, weakly coupled to Tomonaga-Luttinger liquids is
studied, including the action of a strong transverse magnetic field $B$. {We
predict the presence of some peaks in the conductance G versus $B$, related to
the magnetic flux quantization in the ballistic regime (at a very low
temperature, $T$) and also at higher $T$, where the Luttinger behaviour
dominates}. The temperature dependence of the maximum $G_{max}$ of the
conductance peak according to the Sequential Tunneling follows a power law,
$G\propto T^{\gamma_e-1}$ with $\gamma_e$ linearly dependent on the critical
exponent, $\alpha_{end}$, strongly reduced by $B$.


title:
The UV properties of E+A galaxies: constraints on feedback-driven
  quenching of star formation

abstract:
  We present the first large-scale study of E+A (post-starburst) galaxies that
incorporates photometry in the ultraviolet (UV) wavelengths. We find that the
starburst that creates the E+A galaxy typically takes place within the last Gyr
and creates a high fraction (20-60 percent) of the stellar mass in the remnant
over a short timescale (< 0.1 Gyrs). We find a tight correlation between the
luminosity of our E+A galaxies and the implied star formation rate (SFR) during
the starburst. While low-luminosity E+As (M(z) > -20) exhibit implied SFRs of
less than 50 solar masses per year, their luminous counterparts (M(z) < -22)
shows SFRs greater than 300 and as high as 2000 solar masses per year,
suggesting that luminous and ultra-luminous infrared galaxies in the
low-redshift Universe could be the progenitors of massive nearby E+A galaxies.
We perform a comprehensive study of the characteristics of the quenching that
truncates the starburst in E+A systems.We find that, for galaxies less massive
than 10^10 MSun, the quenching efficiency decreases as the galaxy mass
increases. However, for galaxies more massive than 10^10 MSun, this trend is
reversed and the quenching efficiency increases with galaxy mass. Noting that
the mass threshold at which this reversal occurs is in excellent agreement with
the mass above which AGN become significantly more abundant in nearby galaxies,
we use simple energetic arguments to show that the bimodal behaviour of the
quenching efficiency is consistent with AGN and supernovae (SN) being the
principal sources of negative feedback above and below M ~ 10^10 MSun
respectively. (abridged)


title: Investigation of Dust Wake Field Oscillations

abstract:
  Wakefield oscillations created by the ion wakefield existing below a dust
particle within the plasma sheath generated above a powered lower electrode in
a GEC rf reference cell carry information about the plasma sheath, the dust
particle charge and the speed of the streaming ions. An experimental method to
investigate such wakefield oscillations is discussed.


title: Kuranishi homology and Kuranishi cohomology

abstract:
  A Kuranishi space is a topological space with a Kuranishi structure, defined
by Fukaya and Ono. Kuranishi structures occur naturally on moduli spaces of
J-holomorphic curves in symplectic geometry.
  Let Y be an orbifold and R a commutative ring or Q-algebra. We define two
kinds of Kuranishi homology KH_*(Y;R). The chain complex KC_*(Y;R) defining
KH_*(Y;R) is spanned over R by [X,f,G], for X a compact oriented Kuranishi
space with corners, f : X --> Y smooth, and G "gauge-fixing data" which makes
Aut(X,f,G) finite. Our main result is that these are isomorphic to singular
homology. We define Poincare dual Kuranishi cohomology, isomorphic to
compactly-supported cohomology.
  We define five kinds of Kuranishi (co)bordism spanned by isomorphism
classes[X,f] for X a compact oriented Kuranishi space without boundary and f :
X --> Y smooth. They are new topological invariants, and we show they are very
large. These theories are powerful new tools in symplectic geometry. Defining
virtual cycles and chains for moduli spaces of J-holomorphic curves is trivial
in Kuranishi (co)homology. There is no need to perturb moduli spaces, and no
problems with transversality. This gives major simplifications in Lagrangian
Floer cohomology.
  We define new Gromov-Witten type invariants in Kuranishi bordism, over Z not
Q. We sketch how these may be used to prove the integrality conjecture for
Gopakumar-Vafa invariants.
  This paper is surveyed in arXiv:0710.5634.


title:
Particulate Contamination Within Fusion Devices and Complex (Dusty)
  Plasmas

abstract:
  Over the past decade, dust particulate contamination has increasingly become
an area of concern within the fusion research community. In a burning plasma
machine design like the International Thermonuclear Experimental Reactor
(ITER), dust contamination presents problems for diagnostic integration and may
contribute to tritium safety issues. Additionally due to ITER design, such dust
contamination problems are projected to become of even greater concern due to
dust/wall interactions and possible instabilities created within the plasma by
such particulates. Since the dynamics of such dust can in general be explained
employing a combination of the ion drag, Coulomb force, and ion pre-sheath
drifts, recent research in complex (dusty) plasma physics often offers unique
insights for this research area. This paper will discuss the possibility of how
experimental observations of the dust and plasma parameters within a GEC rf
Reference Cell might be employed to diagnose conditions within fusion reactors,
hopefully providing insight into possible mechanisms for dust detection and
removal.


title:
L'orthoglide : une machine-outil rapide d'architecture parall\`ele
  isotrope

abstract:
  This article presents the Orthoglide project. The purpose of this project is
the realization of a prototype of machine tool to three degrees of translation.
The characteristic of this machine is a parallel kinematic architecture
optimized to obtain a compact workspace with homogeneous performance. For that,
the principal criterion of design which was used is the isotropy.


title: An exploratory study of Google Scholar

abstract:
  The paper discusses and analyzes the scientific search service Google Scholar
(GS). The focus is on an exploratory study which investigates the coverage of
scientific serials in GS. The study shows deficiencies in the coverage and
up-to-dateness of the GS index. Furthermore, the study points up which Web
servers are the most important data providers for this search service and which
information sources are highly represented. We can show that there is a
relatively large gap in Google Scholars coverage of German literature as well
as weaknesses in the accessibility of Open Access content.
  Keywords: Search engines, Digital libraries, Worldwide Web, Serials,
Electronic journals


title:
Relativistic multi-reference Fock-space coupled-cluster calculation of
  the forbidden $6s^2^1 S_0 \longrightarrow 6s5d^3 D_1$ magnetic-dipole
  transition in ytterbium

abstract:
  We report the forbidden $6s^{2} ^{1}S_{0}\longrightarrow6s5d ^{3}D_{1}$
magnetic-dipole transition amplitude computed using multi-reference Fock-space
coupled-cluster theory. Our computed transition matrix element
($1.34\times10^{-4}\mu_{B}$) is in excellent agreement with the experimental
value ($1.33\times10^{-4}$ $\mu_{B}$). This value in combination with other
known quantities will be helpful to determine the parity non-conserving
amplitude for the $6s^{2} ^{1}S_{0}\longrightarrow6s5d ^{3}D_{1}$ transition in
atomic Yb. To our knowledge our calculation is the most accurate to date and
can be very important in the search of physics beyond the standard model. We
further report the $6s6p ^{3}P_{0}\longrightarrow6s6p ^{1}P_{1}$ and $6s5d
^{3}D_{1}\longrightarrow6s6p ^{3}P_{0}$ transition matrix elements which are
also in good agreement with the earlier theoretical estimates.


title:
Development of physically based plastic flow rules for body-centered
  cubic metals with temperature and strain rate dependencies

abstract:
  In this Thesis we first show how the shape of the Peierls barrier and its
dependence on the applied loading can be extracted from the data obtained in
atomistic studies at 0 K. We consider the Peierls barrier as a two-dimensional
periodic function of the position of the intersection of the dislocation line
with the perpendicular {111} plane, with adjustable terms dependent on the
shear stresses parallel and perpendicular to the slip direction. The functional
forms of these terms are based on the effective yield criterion recently
developed on the basis of atomistic modeling of the glide of screw dislocations
at 0 K. The minimum energy path between two potential minima, and thus the
corresponding activation barrier, is obtained using the Nudged Elastic Band
method. The constructed Peierls barrier reproduces correctly both the
well-known twinning-antitwinning asymmetry observed for pure shear parallel to
the slip direction and the effect of shear stresses perpendicular to the slip
direction. This advancement introduces for the first time the effect of both
shear stresses parallel and perpendicular to the slip direction into the model
of thermally activated dislocation motion. Based on this model we formulate a
general yield criterion that includes not only the full stress tensor but also
effects of temperature and strain rate. This approach forms a basis for
multislip yield criteria and flow relations for continuum analyses in both
single and polycrystals the results of which can be compared with experimental
observations.


title: The history of star-forming galaxies in the Sloan Digital Sky Survey

abstract:
  We study the evolution of 82302 star-forming (SF) galaxies from the SDSS. Our
main goals are to explore new ways of handling star formation histories (SFH)
obtained with our publicly available spectral synthesis code STARLIGHT, and
apply them to investigate how SFHs vary as a function of nebular metallicity
(Zneb). Our main results are: (1) A conventional correlation analysis shows how
global properties such as luminosity, mass, dust content, mean stellar
metallicity and mean stellar age relate to Zneb. (2) We present a simple
formalism which compresses the results of the synthesis into time-dependent
star formation rates (SFR) and mass assembly histories. (3) The current SFR
derived from the population synthesis and that from H-alpha are shown to agree
within a factor of two. Thus we now have a way to estimate SFR in AGN hosts,
where the H-alpha method cannot be applied. (4) Fully time-dependent SFHs are
derived for all galaxies and averaged over six Zneb bins spanning the entire SF
wing in the [OIII]/H-beta X [NII]/H-alpha diagram. (5) We find that SFHs vary
systematically along the SF sequence, such that low-Zneb systems evolve slower
and are currently forming stars at a higher relative rate. (6) At any given
time, the distribution of specific SFRs for galaxies within a Zneb-bin is broad
and roughly log-normal. (7) The same results are found grouping galaxies in
stellar mass (M*) or surface mass density (S*) bins. (8) The overall pattern of
SFHs as a function of Zneb, M* or S* is robust against changes in selection
criteria, choice of evolutionary synthesis models for the spectral fits, and
differential extinction effects. (Abridged)


title: Origin of the numerals, Zero concept

abstract:
  The partisans of the hypothesis of the Indian origin of the numerals create
confusion between the history of the Indian mathematics and the history of our
modern numerals. To argue the thesis of the Indian origin of the numbers they
confound between: the "intuitive zero " of Brahmagupta, that means ''nothing''
and which is the difference of two equal numbers, the "numeral zero" used in
the representation of the numbers and the "mathematical zero" defined by the
modern mathematicians. "Sifr" designate the "numeral zero" and "Shunya"
designate the "intuitive zero". The word "Sifr" is not a traduction of the word
"Shunya" and does not derive from the Indian word "Shunya", since the word
"Sifr" and its derivatives existed in Arabic long before the appearance of zero
itself The facts that the "intuitive zero" and the "mathematical zero" are
represented currently by the "numerals zero" symbol "0" are only consequences
of the representation of the numbers by the "Ghubari" numerals


title: Spin Hall Effect and Spin Orbit coupling in Ballistic Nanojunctions

abstract:
  We propose a new scheme of spin filtering based on nanometric crossjunctions
in the presence of Spin Orbit interaction, employing ballistic nanojunctions
patterned in a two-dimensional electron gas. We demonstrate that the flow of a
longitudinal unpolarized current through a ballistic X junction patterned in a
two-dimensional electron gas with Spin Orbit coupling (SOC) induces a spin
accumulation which has opposite signs for the two lateral probes. This spin
accumulation, corresponding to a transverse pure spin current flowing in the
junction, is the main observable signature of the spin Hall effect in such
nanostructures.
  We benchmark the effects of two different kinds of Spin Orbit interactions.
The first one ($\alpha$-SOC) is due to the interface electric field that
confines electrons to a two-dimensional layer, whereas the second one
($\beta$-SOC) corresponds to the interaction generated by a lateral confining
potential.


title: Characterizing locally distinguishable orthogonal product states

abstract:
  Bennett et al. \cite{BDF+99} identified a set of orthogonal {\em product}
states in the $3\otimes 3$ Hilbert space such that reliably distinguishing
those states requires non-local quantum operations. While more examples have
been found for this counter-intuitive ``nonlocality without entanglement''
phenomenon, a complete and computationally verifiable characterization for all
such sets of states remains unknown. In this Letter, we give such a
characterization for the $3\otimes 3$ space.


title: An HI Threshold for Star Cluster Formation in Tidal Debris

abstract:
  Super star clusters are young, compact star clusters found in the central
regions of interacting galaxies. Recently, they have also been reported to
preferentially form in certain tidal tails, but not in others. In this paper,
we have used 21 cm HI maps and the Hubble Space Telescope Wide Field Planetary
Camera 2 images of eight tidal tail regions of four merging galaxy pairs to
compare the kiloparsec scale HI distribution with the location of super star
clusters found from the optical images. For most of the tails, we find that
there is an increase in super star cluster density with increasing projected HI
column density, such that the star cluster density is highest when log N(HI) >=
20.6 cm^{-2}, but equal to the background count rate at lower HI column
density. However, for two tails (NGC 4038/39 Pos A and NGC 3921), there is no
significant star cluster population despite the presence of gas at high column
density. This implies that the N(HI) threshold is a necessary but not
sufficient condition for cluster formation. Gas volume density is likely to
provide a more direct criterion for cluster formation, and other factors such
as gas pressure or strength of encounter may also have an influence. Comparison
of HI thresholds needed for formation of different types of stellar structures
await higher resolution HI and optical observations of larger numbers of
interacting galaxies.


title: Generalized Differential Galois Theory

abstract:
  A Galois theory of differential fields with parameters is developed in a
manner that generalizes Kolchin's theory. It is shown that all connected
differential algebraic groups are Galois groups of some appropriate
differential field extension.


title:
The effect of fading, channel inversion, and threshold scheduling on ad
  hoc networks

abstract:
  This paper addresses three issues in the field of ad hoc network capacity:
the impact of i)channel fading, ii) channel inversion power control, and iii)
threshold-based scheduling on capacity. Channel inversion and threshold
scheduling may be viewed as simple ways to exploit channel state information
(CSI) without requiring cooperation across transmitters. We use the
transmission capacity (TC) as our metric, defined as the maximum spatial
intensity of successful simultaneous transmissions subject to a constraint on
the outage probability (OP). By assuming the nodes are located on the infinite
plane according to a Poisson process, we are able to employ tools from
stochastic geometry to obtain asymptotically tight bounds on the distribution
of the signal-to-interference (SIR) level, yielding in turn tight bounds on the
OP (relative to a given SIR threshold) and the TC. We demonstrate that in the
absence of CSI, fading can significantly reduce the TC and somewhat
surprisingly, channel inversion only makes matters worse. We develop a
threshold-based transmission rule where transmitters are active only if the
channel to their receiver is acceptably strong, obtain expressions for the
optimal threshold, and show that this simple, fully distributed scheme can
significantly reduce the effect of fading.


title:
Effects of partial triple excitations in atomic coupled cluster
  calculations

abstract:
  In this article we study the effects of higher body excitations in the
relativistic CC calculations for atoms and ions with one valence electron using
Fock-space CCSD, CCSD(T) and its unitary variants. The present study
demonstrates that CCSD(T) estimates the ionization potentials (IPs) and the
valence electron removal energies quite accurately for alkali atoms and singly
ionized alkaline earth ions, but yields unphysical energy levels for atoms
and/or ions with partially filled sub-shell like C II. We further demonstrate
that the higher body excitation effects can be incorporated more effectively
through the unitary coupled cluster theory (UCC) compared to the CCSD(T)
method.


title: Branching ratios of radiative transitions in O VI

abstract:
  We study the branching ratios of the allowed and forbidden radiative
transitions among the first few (9) fine structure levels of O VI using
relativistic coupled cluster theory. We find irregular patterns for a number of
transitions with in $n$-complexes with $n\le4$. We have used the exisiting
values of the allowed electric dipole ($E1$) transition as a benchmark of our
theory. Good agreement with the existing values establish accuracies of not
only the theoretical method but the basis function as well. In general the
electric quadrupole ($E2$) transition probabilities are greater in magnitude
than magnetic dipole ($M1$) transition probabilities, whereas for medium atomic
transition frequencies they are of the same order of magnitude. On the other
hand if the transitions involved are between two fine structure components of
the same term, then the $M1$ transition probability is more probable than that
of $E2$. We have analyzed these trends with physical arguments and order of
magnitude estimations. The results presented here in tabular and graphical
forms are compared with the available theoretical and observed data. Graphical
analysis helps to understand the trends of electric and magnetic transitions
for the decay channels presented here. Our calculated values of the lifetimes
of the excited states are in very good agreement with the available results.


title:
A relativistic unitary coupled-cluster study of electric quadrupole
  moment and magnetic dipole hyperfine constants of ^{199}Hg^{+}

abstract:
  Searching for an accurate optical clock which can serve as a better time
standard than the present day atomic clock is highly demanding from several
areas of science and technology. Several attempts have been made to built more
accurate clocks with different ion species. In this article we discuss the
electric quadrupole and hyperfine shifts in the $5d^{9}6s^{2}
^{2}D_{5/2}(F=0,m_{F}=0)\leftrightarrow5d^{10}6s ^{2}S_{1/2}(F=2,m_{F}=0)$
clock transition in $ ^{199}Hg^{+}$, one of the most promising candidates for
next generation optical clocks. We have applied Fock-space unitary
coupled-cluster (FSUCC) theory to study the electric quadrupole moment of the
$5d^{9}6s^{2} ^{2}D_{5/2}$ state and magnetic dipole hyperfine constants of
$5d^{9}6s^{2} ^{2}D_{3/2,5/2}$ and $5d^{10}6s^{1} ^{2}S_{1/2}$ states
respectively of $ ^{199}Hg^{+}$. We have also compared our results with
available data. To the best of our knowledge, this is the first time a variant
of coupled-cluster (CC) theories has been applied to study these kinds of
properties of $Hg^{+}$and is the most accurate estimate of these quantities to
date.


title: Magnetic braking in young late-type stars: the effect of polar spots

abstract:
  The concentration of magnetic flux near the poles of rapidly rotating cool
stars has been recently proposed as an alternative mechanism to dynamo
saturation in order to explain the saturation of angular momentum loss. In this
work we study the effect of magnetic surface flux distribution on the coronal
field topology and angular momentum loss rate. We investigate if magnetic flux
concentration towards the pole is a reasonable alternative to dynamo
saturation. We construct a 1D wind model and also apply a 2-D self-similar
analytical model, to evaluate how the surface field distribution affects the
angular momentum loss of the rotating star. From the 1D model we find that, in
a magnetically dominated low corona, the concentrated polar surface field
rapidly expands to regions of low magnetic pressure resulting in a coronal
field with small latitudinal variation. We also find that the angular momentum
loss rate due to a uniform field or a concentrated field with equal total
magnetic flux is very similar. From the 2D wind model we show that there are
several relevant factors to take into account when studying the angular
momentum loss from a star. In particular, we show that the inclusion of force
balance across the field in a wind model is fundamental if realistic
conclusions are to be drawn from the effect of non-uniform surface field
distribution on magnetic braking. This model predicts that a magnetic field
concentrated at high latitudes leads to larger Alfven radii and larger braking
rates than a smoother field distribution. From the results obtained, we argue
that the magnetic surface field distribution towards the pole does not directly
limit the braking efficiency of the wind.


title:
Constraints on the Self-Gravity of Radiation Pressure via Big Bang
  Nucleosynthesis

abstract:
  Using standard big-bang nucleosynthesis and present, high-precision
measurements of light element abundances, we place constraints on the
self-gravity of radiation pressure in the early universe. The self-gravity of
pressure is strictly non-Newtonian, and thus the constraints we set are a
direct test of this aspect of general relativity.


title: Trigonometric Series via Laplace Transforms

abstract:
  The author's method (math-ph/9804010) that uses the Laplace transform to find
exact values for a large class of convergent series is extended to
trigonometric series.


title: New results on the Roper resonance and the P_{11} partial wave

abstract:
  Properties of the Roper resonance, the first scalar excitation of the
nucleon, are determined. Pole positions and residues of the $P_{11}$ partial
wave are studied in a combined analysis of pion- and photo-induced reactions.
We find the Roper pole at $\{(1371\pm7)-i(92\pm10)\}$ MeV and an elasticity of
$0.61\pm 0.03$. The largest decay coupling is found for the $N\sigma$
($\sigma=(\pi\pi)$-$S$-wave). The analysis is based on new data on $\gamma p\to
p\pi^0\pi^0$ for photons in the energy range from the two-pion threshold to 820
MeV from TAPS at Mainz and from 0.4 to 1.3 GeV from Crystal Barrel at Bonn and
includes further data from other experiments. The partial wave analysis
excludes the possibility that the Roper resonance is split into two states with
different partial decay widths.


title: N* and Delta* decays into N pi0 pi0

abstract:
  Decays of baryon resonances in the second and the third resonance region into
N pi0 pi0 are studied by photoproduction of two neutral pions off protons.
Partial decay widths of N* and Delta* resonances decaying into Delta(1232) pi,
N(\pi\pi)_{S}, N(1440)P_{11} pi, and N(1520)D_{13} pi are determined in a
partial wave analysis of this data, and data from other reactions. Several
partial decay widths were not known before. Interesting decay patterns are
observed which are not even qualitatively reproduced by quark model
calculations. In the second resonance region, decays into Delta(1232) pi
dominate clearly. The N(\pi\pi)_{S}-wave provides a significant contribution to
the cross section, especially in the third resonance region. The P_{13}(1720)
properties found here are at clear variance to PDG values.


title:
Finite-Temperature Collective Dynamics of a Fermi Gas in the BEC-BCS
  Crossover

abstract:
  We report on experimental studies on the collective behavior of a strongly
interacting Fermi gas with tunable interactions and variable temperature. A
scissors mode excitation in an elliptical trap is used to characterize the
dynamics of the quantum gas in terms of hydrodynamic or near-collisionless
behavior. We obtain a crossover phase diagram for collisional properties,
showing a large region where a non-superfluid strongly interacting gas shows
hydrodynamic behavior. In a narrow interaction regime on the BCS side of the
crossover, we find a novel temperature-dependent damping peak, suggesting a
relation to the superfluid phase transition.


title: On the spectral functions of scalar mesons

abstract:
  In this work we study the spectral functions of scalar mesons in one- and
two-channel cases. When the propagators satisfy the K\"allen-Lehman
representation a normalized spectral function is obtained, allowing to take
into account finite-width effects in the evaluation of decay rates. In the
one-channel case, suitable to the light sigma and k mesons, the spectral
function can deviate consistently from a Breit-Wigner shape. In the two-channel
case with one subthreshold channel the evaluated spectral function is well
approximated by a Flatte' distribution; when applying the study to the a_0(980)
and f_0(980) mesons the tree-level forbidden KK decay is analysed.


title: The Noncommutative Standard Model at O(theta^2)

abstract:
  We derive the most general Seiberg-Witten maps for noncommutative gauge
theories in second order of the noncommutative parameter theta. Our results
reveal the existence of more ambiguities than previously known. In particular,
we demonstrate that some of these ambiguities enter observables like scattering
cross sections and enlarge the parameter space of the noncommutative standard
model beyond O(theta).


title: Baryon resonances and polarization transfer in hyperon photoproduction

abstract:
  A partial wave analysis is presented of data on photoproduction of hyperons
including single and double polarization observables. The large spin transfer
probability reported by the CLAS collaboration can be successfully described
with an isobar partial wave analysis.


title:
Exceptional representations of a double quiver of type A, and Richardson
  elements in seaweed Lie algebras

abstract:
  In this paper, we study the set of $\Delta$-filtered modules of
quasi-hereditary algebras arising from quotients of the double of quivers of
type $A$. Our main result is that for any fixed $\Delta$-dimension vector,
there is a unique (up to isomorphism) exceptional $\Delta$-filtered module. We
then apply this result to show that there is always an open adjoint orbit in
the nilpotent radical of a seaweed Lie algebra in $\mathrm{gl}_{n}(\field)$,
thus answering positively in this $\mathrm{gl}_{n}(\field)$ case to a question
raised independently by Michel Duflo and Dmitri Panyushev. An example of a
seaweed Lie algebra in a simple Lie algebra of type $E_{8}$ not admitting an
open orbit in its nilpotent radical is given.


title: On the dihedral n-body problem

abstract:
  Consider n=2l>=4 point particles with equal masses in space, subject to the
following symmetry constraint: at each instant they form an orbit of the
dihedral group D_l, where D_l is the group of order 2l generated by two
rotations of angle pi around two secant lines in space meeting at an angle of
pi/l. By adding a homogeneous gravitational (Newtonian) potential one finds a
special $n$-body problem with three degrees of freedom, which is a kind of
generalisation of Devaney isosceles problem, in which all orbits have zero
angular momentum. In the paper we find all the central configurations and we
compute the dimension of the stable/unstable manifolds.


title: Theory for p-Wave Feshbach Molecules

abstract:
  We determine the physical properties of \emph{p}-wave Feshbach molecules in
doubly spin-polarized $^{40}$K and find excellent agreement with recent
experiments. We show that these molecules have a large probability $Z$ to be in
the closed channel or bare molecular state responsible for the Feshbach
resonance. In the superfluid state this allows for observation of Rabi
oscillations between the molecular and atomic components of the Bose-Einstein
condensed pairs, which contains a characteristic signature of the quantum phase
transition that occurs as a function of applied magnetic field.


title: Further evidence for N(1900)P_{13} from photoproduction of hyperons

abstract:
  We report further evidence for $N(1900)P_{13}$ from an analysis of a large
variety of photo- and pion-induced reactions, in particular from the new CLAS
measurements of double polarization observables for photoproduction of
hyperons. The data are consistent with two classes of solutions both requiring
contributions from $N(1900)P_{13}$ but giving different $N(1900)P_{13}$ pole
positions. $(M-i\Gamma/2) = (1915\pm50)-i(90\pm25)$ MeV covers both solutions.
The small elasticity of 10% or less explains why it was difficult to observe
the state in $\pi N$ elastic scattering.
  $N(1900)P_{13}$ is a 2-star resonance which is predicted by symmetric
three-quark models. In diquark-quark models, the existence of the state is not
expected.


title: Entropy of near-extremal black holes in AdS_5

abstract:
  We construct the microstates of near-extremal black holes in AdS_5 x S^5 as
gases of defects distributed in heavy BPS operators in the dual SU(N)
Yang-Mills theory. These defects describe open strings on spherical D3-branes
in the S^5, and we show that they dominate the entropy by directly enumerating
them and comparing the results with a partition sum calculation. We display new
decoupling limits in which the field theory of the lightest open strings on the
D-branes becomes dual to a near-horizon region of the black hole geometry. In
the single-charge black hole we find evidence for an infrared duality between
SU(N) Yang-Mills theories that exchanges the rank of the gauge group with an
R-charge. In the two-charge case (where pairs of branes intersect on a line),
the decoupled geometry includes an AdS_3 factor with a two-dimensional CFT
dual. The degeneracy in this CFT accounts for the black hole entropy. In the
three-charge case (where triples of branes intersect at a point), the decoupled
geometry contains an AdS_2 factor. Below a certain critical mass, the
two-charge system displays solutions with naked timelike singularities even
though they do not violate a BPS bound. We suggest a string theoretic
resolution of these singularities.


title:
Precise Particle Tracking Against a Complicated Background: Polynomial
  Fitting with Gaussian Weight

abstract:
  We present a new particle tracking software algorithm designed to accurately
track the motion of low-contrast particles against a background with large
variations in light levels. The method is based on a polynomial fit of the
intensity around each feature point, weighted by a Gaussian function of the
distance from the centre, and is especially suitable for tracking endogeneous
particles in the cell, imaged with bright field, phase contrast or fluorescence
optical microscopy. Furthermore, the method can simultaneously track particles
of all different sizes, and allows significant freedom in their shape. The
algorithm is evaluated using the quantitative measures of accuracy and
precision of previous authors, using simulated images at variable
signal-to-noise ratios. To these we add a new test of the error due to a
non-uniform background. Finally the tracking of particles in real cell images
is demonstrated. The method is made freely available for non-commencial use as
a software package with a graphical user-inferface, which can be run within the
Matlab programming environment.


title: Sur la cat\'egorie des bimodules de Soergel

abstract:
  The Soergel category B of a Coxeter system (W,S) is a bimodule category over
a polynomial algebra on which W acts. It's a categorification of the Hecke
Algebra of (W,S). In this article we give a combinatorial description of
morphism spaces in B. As a corollary, we give an analogous description of the
morphisms in O_0-proj, where O_0 is the principal block of the BGG category O.
  -----
  La cat\'egorie B de Soergel d'un syst\`eme de Coxeter (W,S) est une
cat\'egorie de bimodules sur une alg\`ebre de polyn\^omes sur laquelle W agit.
C'est une cat\'egorification de l'alg\`ebre de Hecke de (W,S). Dans cet article
nous donnons une description combinatoire des espaces de morphismes dans B. En
corollaire, on obtient une description analogue des morphismes dans O_0-proj,
o\`u O_0 est le bloc principal de la cat\'egorie O de BGG.


title: A New Low-Mass Eclipsing Binary from SDSS-II

abstract:
  We present observations of a new low-mass double-lined eclipsing binary
system discovered using repeat observations of the celestial equator from the
Sloan Digital Sky Survey II. Using near-infrared photometry and optical
spectroscopy we have measured the properties of this short-period
[P=0.407037(14) d] system and its two components. We find the following
parameters for the two components: M_1=0.272+/-0.020 M_sun, R_1=0.268+/-0.010
R_sun, M_2=0.240+/-0.022 M_sun, R_2=0.248+/-0.0090 R_sun, T_1=3320+/-130 K,
T_2=3300+/-130 K. The masses and radii of the two components of this system
agree well with theoretical expectations based on models of low-mass stars,
within the admittedly large errors. Future synoptic surveys like Pan-STARRS and
LSST will produce a wealth of information about low-mass eclipsing systems and
should make it possible, with an increased reliance on follow-up observations,
to detect many systems with low-mass and sub-stellar companions. With the large
numbers of objects for which these surveys will produce high-quality
photometry, we suggest that it becomes possible to identify such systems even
with sparse time sampling and a relatively small number of individual
observations.


title: Astroparticle Physics with AMS02

abstract:
  The Alpha Magnetic Spectrometer (AMS02) experiment will be installed in 2009
on the International Space Station (ISS) for an operational period of at least
three years. The purpose of AMS02 experiment is to perform accurate, high
statistics, long duration measurements in space of charged cosmic rays in
rigidity range from 1 GV to 3 TV and of high energy photons up to few hundred
of GeV. In this work we will discuss the experimental details and the physics
capabilities of AMS02 on ISS.


title:
How a protein searches for its specific site on DNA: the role of
  intersegment transfer

abstract:
  Proteins are known to locate their specific targets on DNA up to two orders
of magnitude faster than predicted by the Smoluchowski three-dimensional
diffusion rate. One of the mechanisms proposed to resolve this discrepancy is
termed "intersegment transfer". Many proteins have two DNA binding sites and
can transfer from one DNA segment to another without dissociation to water. We
calculate the target search rate for such proteins in a dense globular DNA,
taking into account intersegment transfer working in conjunction with DNA
motion and protein sliding along DNA. We show that intersegment transfer plays
a very important role in cases where the protein spends most of its time
adsorbed on DNA.


title: Algebras associated to acyclic directed graphs

abstract:
  We construct and study a class of algebras associated to generalized layered
graphs, i.e. directed graphs with a ranking function on their vertices. Each
finite directed acyclic graph admits countably many structures of a generalized
layered graph. We construct linear bases in such algebras and compute their
Hilbert series. Our interest to generalized layered graphs and algebras
associated to those graphs is motivated by their relations to factorizations of
polynomials over noncommutative rings.


title: An equivalent condition for a uniform space to be coverable

abstract:
  We prove that an equivalent condition for a uniform space to be coverable is
that the images of the natural projections in the fundamental inverse system
are uniformly open in a certain sense. As corollaries we (1) obtain a concrete
way to find covering entourage, (2) correct an error in [3] and (3) show that
coverable is equivalent to chain connected and uniformly joinable in the sense
of arXiv:0706.3937.


title: Covering R-trees

abstract:
  We show that every inner metric space X is the metric quotient of a complete
R-tree via a free isometric action, which we call the covering R-tree of X. The
quotient mapping is a weak submetry (hence, open) and light. In the case of
compact 1-dimensional geodesic space X, the free isometric action is via a
subgroup of the fundamental group of X. In particular, the Sierpin'ski gasket
and carpet, and the Menger sponge all have the same covering R-tree, which is
complete and has at each point valency equal to the continuum. This latter
R-tree is of particular interest because it is "universal" in at least two
senses: First, every R-tree of valency at most the continuum can be
isometrically embedded in it. Second, every Peano continuum is the image of it
via an open light mapping. We provide a sketch of our previous construction of
the uniform universal cover in the special case of inner metric spaces, the
properties of which are used in the proof.


title: P-term Strings and Semi-local Strings

abstract:
  P-term potentials can give rise to Nielsen-Olesen or semi-local cosmic
strings. We present a general analysis of these cosmic strings where we derive
the Bogomol'nyi equations and field profiles for both types of string and
discuss their stability. We give an analysis of the fermionic zero modes that
could live on the strings and a brief discussion of the inflationary period
preceding their formation.


title:
Improved Landau gauge fixing and the suppression of finite-volume
  effects of the lattice gluon propagator

abstract:
  For the gluon propagator of pure SU(2) lattice gauge theory in the Landau
gauge we investigate the effect of Gribov copies and finite-volume effects.
Concerning gauge fixing, we enlarge the accessible gauge orbits by adding
non-periodic Z(2) gauge transformations and systematically employ the simulated
annealing algorithm. Strategies to keep all Z(2) sectors under control within
reasonable CPU time are discussed. We demonstrate that the finite-volume
effects in the infrared regime become ameliorated. Reaching a physical volume
of about (6.5 fm)^4, we find that the propagator, calculated with the indicated
improvements, becomes flat in the region of smallest momenta. First signs in 4d
of a final decrease towards vanishing momentum are discussed.


title:
Comment on Nongeometric Conditional Phase Shift via Adiabatic Evolution
  of Dark Eigenstate

abstract:
  In a recent letter [Phy. Rev. Lett. 95, 080502 (2005)], it is claimed that
based on a new kind of quantum mechanical phase of wave function which is
neither dynamical nor geometrical a new kind of phase gate for quantum
computation is discovered. The origin of this phase is the adiabatic evolution
of a dark state. I would like to point out that these claims are questionable.
The so called new phase gate was based on a phase which was nothing new but has
been known for decades. It is something which has no physical meaning and is
not observable. It was also pointed out by [quant-ph/0509150v1] that [Phy. Rev.
Lett. 95, 080502 (2005)] was incorrect and the phase is the known geometric
phase. Here we present a totally different argument.


title:
Critical Current 0-$\pi$ Transition in Designed Josephson Quantum Dot
  Junctions

abstract:
  We report on quantum dot based Josephson junctions designed specifically for
measuring the supercurrent. From high-accuracy fitting of the current-voltage
characteristics we determine the full magnitude of the supercurrent (critical
current). Strong gate modulation of the critical current is observed through
several consecutive Coulomb blockade oscillations. The critical current crosses
zero close to, but not at, resonance due to the so-called 0-$\pi$ transition in
agreement with a simple theoretical model.


title: Terahertz spectroscopy of electromagnons in Eu_{1-x}Y_xMnO_3

abstract:
  Dielectric permittivity spectra of yttrium-doped EuMnO$_3$ in the composition
range 0 =< x =< 0.5 have been investigated in the terahertz frequency range.
Magnetoelectric contributions to the permittivity were observed in all
compositions for ac electric fields parallel to the crystallographic a-axis.
Well defined electromagnons exist for x >= 0.2 close to \nu ~ 20 cm^{-1} and
with dielectric strength strongly increasing on doping. In addition to
electromagnons, a broad contribution of magnetoelectric origin is observed for
all compositions. For Eu_{0.8}Y_{0.2}MnO_3 the electromagnons can be suppressed
by external magnetic fields which induce a canted antiferromagnetic phase.
Magnetoelectric effects in the different doping regimes are discussed in
detail.


title: Two Analogs of Intrinsically Linked Graphs

abstract:
  A graph G is intrinsically S^1-linked if for every embedding of the vertices
of G into S^1, vertices that form the endpoints of two disjoint edges in G form
a non-split link in the embedding. We show that a graph is intrinsically
S^1-linked if and only if it is not outer-planar. A graph is outer-flat if it
can be embedded in the 3-ball such that all of its vertices map to the boundary
of the 3-ball, all edges to the interior, and every cycle bounds a disk in the
3-ball that meets the graph only along its boundary. We show that a graph is
outer-flat if and only if it is planar.


title:
Experimental search for dynamic heterogeneities in molecular glass
  formers

abstract:
  We have measured the linear dielectric susceptibility of two molecular glass
formers close to Tg in order to estimate the size of the dynamically correlated
clusters of molecules which are expected to govern the physics of glass
formation. This size has been shown to be related to the dynamic dielectric
susceptibility dEps(w)/dT (Eps : dielectric susceptibility, T : temperature,
w: frequency). To allow for an accurate determination of the T
derivative, we scanned the interval 192 < T < 232 K every 1 K for glycerol and
159 < T < 179 K every 0.5 K for propylene carbonate. The resolution on T
variations was about 1 mK. The result for glycerol is that the number of
correlated molecules increases by a factor 3 when T goes from 226 to 195 K. It
has been shown that the non-linear susceptibility provides a direct measurement
of dynamic correlations. To measure it, we used a standard Lockin technique
yielding the third harmonic of the current flowing out of a capacitor. We
obtained only an upper limit on the ratio of the third to the first harmonic,
due to the non-linear response of standard electronics.


title: Extraction Of Delta g/g From Hermes Data On Inclusive Charged Hadrons

abstract:
  Hermes has measured longitudinal double spin asymmetries as a function of
transverse momentum pT using charged inclusive hadrons from electroproduction
off a deuterium target. At pT>1 GeV, the asymmetries are sensitive to the spin
dependent gluon distribution Delta g. To extract the gluon polarization Delta
g/g, information on the background asymmetry and the subprocess kinematics has
been obtained from a Leading Order Monte Carlo model. Values for Delta g/g have
been calculated both as a function of the measured pT and x, using two
different methods, in the region pT>1.05 GeV.


title: Particle production mechanisms from RHIC to LHC

abstract:
  I will review RHIC data with respect to the intriguing possibility that the
hadron production mechanism in the produced partonic medium might be different
than in vacuum. I will use the measurements of collective features, such as
flow and quenching of identified particles, to show that different regions of
the particle momentum spectrum are likely populated through different
mechanisms, and that the medium seems to play an important role in
hadronization. Finally I will address the question whether the different
initial conditions achievable in heavy ion collisions at LHC energies, compared
to RHIC, might affect the properties of the deconfined quark-gluon phase and
its hadronization to baryonic matter.


title: Semi-local string comparison: algorithmic techniques and applications

abstract:
  A classical measure of string comparison is given by the longest common
subsequence (LCS) problem on a pair of strings. We consider its generalisation,
called the semi-local LCS problem, which arises naturally in many
string-related problems. The semi-local LCS problem asks for the LCS scores for
each of the input strings against every substring of the other input string,
and for every prefix of each input string against every suffix of the other
input string. Such a comparison pattern provides a much more detailed picture
of string similarity than a single LCS score; it also arises naturally in many
string-related problems. In fact, the semi-local LCS problem turns out to be
fundamental for string comparison, providing a powerful and flexible
alternative to classical dynamic programming. It is especially useful when the
input to a string comparison problem may not be available all at once: for
example, comparison of dynamically changing strings; comparison of compressed
strings; parallel string comparison. The same approach can also be applied to
permutation strings, providing efficient solutions for local versions of the
longest increasing subsequence (LIS) problem, and for the problem of computing
a maximum clique in a circle graph. Furthermore, the semi-local LCS problem
turns out to have surprising connections in a few seemingly unrelated fields,
such as computational geometry and algebra of semigroups. This work is devoted
to exploring the structure of the semi-local LCS problem, its efficient
solutions, and its applications in string comparison and other related areas,
including computational molecular biology.


title:
Energy spectra stemming from interactions of Alfven waves and turbulent
  eddies

abstract:
  We present a numerical analysis of an incompressible decaying
magnetohydrodynamic turbulence run on a grid of 1536^3 points. The Taylor
Reynolds number at the maximum of dissipation is ~1100, and the initial
condition is a superposition of large scale ABC flows and random noise at small
scales, with no uniform magnetic field. The initial kinetic and magnetic
energies are equal, with negligible correlation. The resulting energy spectrum
is a combination of two components, each moderately resolved. Isotropy obtains
in the large scales, with a spectral law compatible with the
Iroshnikov-Kraichnan theory stemming from the weakening of nonlinear
interactions due to Alfven waves; scaling of structure functions confirms the
non-Kolmogorovian nature of the flow in this range. At small scales, weak
turbulence emerges with a k_{\perp}^{-2} spectrum, the perpendicular direction
referring to the local quasi-uniform magnetic field.


title: Critical Line in Random Threshold Networks with Inhomogeneous Thresholds

abstract:
  We calculate analytically the critical connectivity $K_c$ of Random Threshold
Networks (RTN) for homogeneous and inhomogeneous thresholds, and confirm the
results by numerical simulations. We find a super-linear increase of $K_c$ with
the (average) absolute threshold $|h|$, which approaches $K_c(|h|) \sim
h^2/(2\ln{|h|})$ for large $|h|$, and show that this asymptotic scaling is
universal for RTN with Poissonian distributed connectivity and threshold
distributions with a variance that grows slower than $h^2$. Interestingly, we
find that inhomogeneous distribution of thresholds leads to increased
propagation of perturbations for sparsely connected networks, while for densely
connected networks damage is reduced; the cross-over point yields a novel,
characteristic connectivity $K_d$, that has no counterpart in Boolean networks.
Last, local correlations between node thresholds and in-degree are introduced.
Here, numerical simulations show that even weak (anti-)correlations can lead to
a transition from ordered to chaotic dynamics, and vice versa. It is shown that
the naive mean-field assumption typical for the annealed approximation leads to
false predictions in this case, since correlations between thresholds and
out-degree that emerge as a side-effect strongly modify damage propagation
behavior.

categories: cond-mat.dis-nn cond-mat.stat-mech nlin.CG q-bio.MN


title: Constant-degree graph expansions that preserve the treewidth

abstract:
  Many hard algorithmic problems dealing with graphs, circuits, formulas and
constraints admit polynomial-time upper bounds if the underlying graph has
small treewidth. The same problems often encourage reducing the maximal degree
of vertices to simplify theoretical arguments or address practical concerns.
Such degree reduction can be performed through a sequence of splittings of
vertices, resulting in an _expansion_ of the original graph. We observe that
the treewidth of a graph may increase dramatically if the splittings are not
performed carefully. In this context we address the following natural question:
is it possible to reduce the maximum degree to a constant without substantially
increasing the treewidth?
  Our work answers the above question affirmatively. We prove that any simple
undirected graph G=(V, E) admits an expansion G'=(V', E') with the maximum
degree <= 3 and treewidth(G') <= treewidth(G)+1. Furthermore, such an expansion
will have no more than 2|E|+|V| vertices and 3|E| edges; it can be computed
efficiently from a tree-decomposition of G. We also construct a family of
examples for which the increase by 1 in treewidth cannot be avoided.


title:
Role of magnetism and electron-lattice interactions in STM spectra of
  cuprates

abstract:
  The study of bosonic modes that couple to the charge carriers is a key
element in understanding superconductivity. Lee et al. have used
atomic-resolution scanning tunneling spectroscopy (STM) in an attempt to
extract the spectrum of of these modes in the high temperature superconductor
Bi2Sr2CaCu2O8+d and they found a mode whose frequency did not depend on doping
but changed on 16O to 18O isotopic substitution leading them to suggest a role
for lattice modes (phonons). A careful examination of their published data
reveals a weaker but distinct feature that has all the characteristics of the
magnetic excitation identified as the bosonic mode in other competing
experiments. We suggest the lattice mode seen by Lee et al. is not relevant to
superconductivity and is due to inelastic tunneling through the insulating
oxide layer.


title:
Shape-invariant quantum Hamiltonian with position-dependent effective
  mass through second order supersymmetry

abstract:
  Second order supersymmetric approach is taken to the system describing motion
of a quantum particle in a potential endowed with position-dependent effective
mass. It is shown that the intertwining relations between second order partner
Hamiltonians may be exploited to obtain a simple shape-invariant condition.
Indeed a novel relation between potential and mass functions is derived, which
leads to a class of exactly solvable model. As an illustration of our
procedure, two examples are given for which one obtains whole spectra
algebraically. Both shape-invariant potentials exhibit harmonic-oscillator-like
or singular-oscillator-like spectra depending on the values of the
shape-invariant parameter.


title: Quasars with a Kick -- Black Hole Recoil in Quasars

abstract:
  Mergers of spinning black holes can give recoil velocities from gravitational
radiation up to several thousand km/s. A recoiling supermassive black hole in
an AGN can retain the inner part of its accretion disk, providing fuel for
continuing AGN activity. Using AGN in the Sloan Digital Sky Survey (SDSS) that
show velocity shifts of the broad emission lines relative to the narrow lines,
we place upper limits on the incidence of high velocity recoils in AGN. Brief
but powerful flares in soft X-rays may occur when bound material falls back
into the moving accretion disk.


title:
Intrinsic spin-Hall accumulation in honeycomb lattices: Band structure
  effects

abstract:
  Local spin and charge densities on a two-dimensional honeycomb lattice are
calculated by the Landauer-Keldysh formalism (LKF). Through the empirical
tight-binding method, we show how the realistic band structure can be brought
into the LKF. Taking the Bi(111) surface, on which strong surface states and
Rashba spin-orbit coupling are present [Phys. Rev. Lett. 93, 046403 (2004)], as
a numeric example, we show typical intrinsic spin-Hall accumulation (ISHA)
patterns thereon. The Fermi-energy-dependence of the spin and charge transport
in two-terminal nanostructure samples is subsequently analyzed. By changing
E_{F}, we show that the ISHA pattern is nearly isotropic (free-electron-like)
only when E_{F} is close to the band bottom, and is sensitive/insensitive to
E_{F} for the low/high bias regime with such E_{F}. With E_{F} far from the
band bottom, band structure effects thus enter the ISHA patterns and the
transport direction becomes significant.


title: Prime Ideals of q-Commutative Power Series Rings

abstract:
  We study the "q-commutative" power series ring R:=k_q[[x_1,...,x_n]], defined
by the relations x_ix_j = q_{ij}x_j x_i, for multiplicatively antisymmetric
scalars q_{ij} in a field k. Our results provide a detailed account of prime
ideal structure for a class of noncommutative, complete, local, noetherian
domains having arbitrarily high (but finite) Krull, global, and classical Krull
dimension. In particular, we prove that the prime spectrum of R is normally
separated and is finitely stratified by commutative noetherian spectra.
Combining this normal separation with results of Chan, Wu, Yekutieli, and
Zhang, we are able to conclude that R is catenary. Following the approach of
Brown and Goodearl, we also show that links between prime ideals are provided
by canonical automorphisms. Moreover, for sufficiently generic q_{ij}, we find
that R has only finitely many prime ideals and is a UFD (in the sense of
Chatters).


title: On the type of triangle groups

abstract:
  We prove a conjecture of R. Schwartz about the type of some complex
hyperbolic triangle groups.


title: Non-monotonic zero point entropy in diluted spin ice

abstract:
  Water ice and spin ice are important model systems in which theory can
directly account for zero point entropy associated with quenched
configurational disorder. Spin ice differs from water ice in the important
respect that its fundamental constituents, the spins of the magnetic ions, can
be removed through replacement with non-magnetic ions while keeping the lattice
structure intact. In order to investigate the interplay of frustrated
interactions and quenched disorder, we have performed systematic heat capacity
measurements on spin ice materials which have been thus diluted up to 90%.
Investigations of both Ho and Dy spin ices reveal that the zero point entropy
depends non-monotonically on dilution and approaches the value of Rln2 in the
limit of high dilution. The data are in good agreement with a generalization of
Pauling's theory for the entropy of ice.


title:
Molecular production at a wide Feshbach resonance in Fermi-gas of cooled
  atoms

abstract:
  The problem of molecular production from degenerate gas of fermions at a wide
Feshbach resonance, in a single-mode approximation, is reduced to the linear
Landau-Zener problem for operators. The strong interaction leads to significant
renormalization of the gap between adiabatic levels. In contrast to static
problem the close vicinity of exact resonance does not play substantial role.
Two main physical results of our theory is the high sensitivity of molecular
production to the initial value of magnetic field and generation of a large BCS
condensate distributed over a broad range of momenta in inverse process of the
molecule dissociation.


title: Isoperimetric inequalities for eigenvalues of triangles

abstract:
  Lower bounds estimates are proved for the first eigenvalue for the Dirichlet
Laplacian on arbitrary triangles using various symmetrization techniques. These
results can viewed as a generalization of P\'olya's isoperimetric bounds. It is
also shown that amongst triangles, the equilateral triangle minimizes the
spectral gap and (under additional assumption) the ratio of the first two
eigenvalues. This last result resembles the Payne-P\'olya-Weinberger conjecture
proved by Ashbaugh and Benguria.


title: Sharp bounds on 2m/r for static spherical objects

abstract:
  Sharp bounds are obtained, under a variety of assumptions on the eigenvalues
of the Einstein tensor, for the ratio of the Hawking mass to the areal radius
in static, spherically symmetric space-times.


title:
Do mixtures of bosonic and fermionic atoms adiabatically heat up in
  optical lattices?

abstract:
  Mixtures of bosonic and fermionic atoms in optical lattices provide a
promising arena to study strongly correlated systems. In experiments realizing
such mixtures in the quantum degenerate regime the temperature is a key
parameter. In this work, we investigate the intrinsic heating and cooling
effects due to an entropy-preserving raising of the optical lattice potential.
We analyze this process, identify the generic behavior valid for a wide range
of parameters, and discuss it quantitatively for the recent experiments with
87Rb and 40K atoms. In the absence of a lattice, we treat the bosons in the
Hartree-Fock-Bogoliubov-Popov-approximation, including the fermions in a
self-consistent mean field interaction. In the presence of the full
three-dimensional lattice, we use a strong coupling expansion. As a result of
the presence of the fermions, the temperature of the mixture after the lattice
ramp-up is always higher than for the pure bosonic case. This sheds light onto
a key point in the analysis of recent experiments.


title:
Integral Field Spectroscopy of High-Redshift Star Forming Galaxies with
  Laser Guided Adaptive Optics: Evidence for Dispersion-Dominated Kinematics

abstract:
  We present early results from an ongoing study of the kinematic structure of
star-forming galaxies at redshift z ~ 2 - 3 using integral-field spectroscopy
of rest-frame optical nebular emission lines in combination with Keck laser
guide star adaptive optics (LGSAO). We show kinematic maps of 3 target galaxies
Q1623-BX453, Q0449-BX93, and DSF2237a-C2 located at redshifts z = 2.1820,
2.0067, and 3.3172 respectively, each of which is well-resolved with a PSF
measuring approximately 0.11 - 0.15 arcsec (~ 900 - 1200 pc at z ~ 2-3) after
cosmetic smoothing. Neither galaxy at z ~ 2 exhibits substantial kinematic
structure on scales >~ 30 km/s; both are instead consistent with largely
dispersion-dominated velocity fields with sigma ~ 80 km/s along any given line
of sight into the galaxy. In contrast, DSF2237a-C2 presents a well-resolved
gradient in velocity over a distance of ~ 4 kpc with peak-to-peak amplitude of
140 km/s. It is unlikely that DSF2237a-C2 represents a dynamically cold
rotating disk of ionized gas as the local velocity dispersion of the galaxy
(sigma = 79 km/s) is comparable to the observed shear. Using extant
multi-wavelength spectroscopy and photometry we relate these kinematic data to
physical properties such as stellar mass, gas fraction, star formation rate,
and outflow kinematics and consider the applicability of current galaxy
formation models.[Abridged]


title: A Model for Fast Rising, Slowly Decaying Subpulses in Gamma-Ray Bursts

abstract:
  Gamma ray bursts (GRB's) often feature subpulses that have a distinctively
asymmetric profile -- they rise quickly and decay much more slowly, while their
spectrum softens slightly with observer time. It is suggested that these
subpulses are caused by slow baryonic clouds embedded within a primary
$\gamma$-ray beam, which scatter the $\gamma$-radiation into our line of sight
as they accelerate. Good quantitative agreement is obtained with observed light
curves and spectral evolution. The kinetic energy that the baryonic component
of GRB jets receives from the primary $\gamma$-radiation is predicted to be
about equal to the amount of $\gamma$-radiation that is scattered, consistent
with observations of afterglow. Several other observational consequences are
briefly discussed. The possibility is raised that the time scale of short GRB
is established by radiative acceleration and/or baryon injection rather than
the time scale of the central engine.


title: Cooling of young stars growing by disk accretion

abstract:
  In the initial formation stages young stars must acquire a significant
fraction of their mass by accretion from a circumstellar disk that forms in the
center of a collapsing protostellar cloud. Throughout this period mass
accretion rates through the disk can reach 10^{-6}-10^{-5} M_Sun/yr leading to
substantial energy release in the vicinity of stellar surface. We study the
impact of irradiation of the stellar surface produced by the hot inner disk on
properties of accreting fully convective low-mass stars, and also look at
objects such as young brown dwarfs and giant planets. At high accretion rates
irradiation raises the surface temperature of the equatorial region above the
photospheric temperature T_0 that a star would have in the absence of
accretion. The high-latitude (polar) parts of the stellar surface, where disk
irradiation is weak, preserve their temperature at the level of T_0. In
strongly irradiated regions an almost isothermal outer radiative zone forms on
top of the fully convective interior, leading to the suppression of the local
internal cooling flux derived from stellar contraction (similar suppression
occurs in irradiated ``hot Jupiters''). Properties of this radiative zone
likely determine the amount of thermal energy that gets advected into the
convective interior of the star. Total intrinsic luminosity integrated over the
whole stellar surface is reduced compared to the non-accreting case, by up to a
factor of several in some systems (young brown dwarfs, stars in quasar disks,
forming giants planets), potentially leading to the retardation of stellar
contraction. Stars and brown dwarfs irradiated by their disks tend to lose
energy predominantly through their cool polar regions while young giant planets
accreting through the disk cool through their whole surface.


title: Fractional Quantum Hall States and Jack Polynomials

abstract:
  We describe an occupation-number-like picture of Fractional Quantum Hall
(FQH) states in terms of polynomial wavefunctions characterized by a dominant
occupation-number configuration. The bosonic variants of single-component
abelian and non-abelian FQH states are modeled by Jacks (Jack symmetric
polynomials), characterized by dominant occupation-number configurations
satisfying a generalized Pauli principle. In a series of well-known Quantum
Hall states, including the Laughlin, Read-Moore, and Read-Rezayi, the Jack
polynomials naturally implement a ``squeezing rule'' that constrains allowed
configurations to be restricted to those obtained by squeezing the dominant
configuration. The Jacks describing uniform FQH states satisfy a highest-weight
condition, and a clustering condition which can be generalized to describe
quasiparticle states.


title: The Review and Analysis of Human Computer Interaction (HCI) Principles

abstract:
  The History of HCI is briefly reviewed together with three HCI models and
structure including CSCW, CSCL and CSCR. It is shown that a number of
authorities consider HCI to be a fragmented discipline with no agreed set of
unifying design principles. An analysis of usability criteria based upon
citation frequency of authors is performed in order to discover the eight most
recognised HCI principles.


title: The Minimum Amount of Stars a Galaxy Will Form

abstract:
  We present an analysis of the atomic hydrogen and stellar properties of 38
late-type galaxies in the local Universe covering a wide range of HI
mass-to-light ratios (M_HI/L_B), stellar luminosities, and surface
brightnesses. From these data we have identified an upper envelope for the
M_HI/L_B as a function of galaxy luminosity. This implies an empirical relation
between the minimum amount of stars a galaxy will form and its initial baryonic
mass. While the stellar mass of a galaxy seems to be only loosely connected to
its baryonic mass, the latter quantity is strongly linked to the galaxy's
dynamical mass as it is observed in the baryonic Tully-Fisher relation. We find
that dwarf irregular galaxies with generally high M_HI/L_B-ratios follow the
same trend as defined by lower M_HI/L_B giant galaxies, but are underluminous
for their rotation velocity to follow the trend in a stellar mass Tully-Fisher
relation, suggesting that the baryonic mass of the dwarf galaxies is normal but
they have failed to produced a sufficient amount of stars. Finally, we present
a three dimensional equivalent to the morphology-density relation which shows
that high M_HI/L_B galaxies preferentially evolve and/or survive in low-density
environments. We conclude that an isolated galaxy with a shallow dark matter
potential can retain a large portion of its baryonic matter in the form of gas,
only producing a minimum quantity of stars necessary to maintain a stable gas
disk.


title: Deformation bicomplex of module-algebras

abstract:
  The deformation bicomplex of a module-algebra over a bialgebra is
constructed. It is then applied to study algebraic deformations in which both
the module structure and the algebra structure are deformed. The cases of
module-coalgebras, comodule-(co)algebras, and (co)module-bialgebras are also
considered.


title: Non-Magnetic Cloak without Reflection

abstract:
  In an electromagnetic cloak based on a transformation approach, reduced sets
of material properties are generally favored due to their easier implementation
in reality, although a seemingly inevitable drawback of undesired reflection
exists in such cloaks. Here we suggest using high-order transformations to
create smooth moduli at the outer boundary of the cloak, therefore completely
eliminating the detrimental scattering within the limit of geometric optics. We
apply this scheme to a non-magnetic cylindrical cloak and demonstrate that the
scattered field is reduced substantially in a cloak with optimal quadratic
transformation as compared to its linear counterpart.


title: Mutual information in random Boolean models of regulatory networks

abstract:
  The amount of mutual information contained in time series of two elements
gives a measure of how well their activities are coordinated. In a large,
complex network of interacting elements, such as a genetic regulatory network
within a cell, the average of the mutual information over all pairs <I> is a
global measure of how well the system can coordinate its internal dynamics. We
study this average pairwise mutual information in random Boolean networks
(RBNs) as a function of the distribution of Boolean rules implemented at each
element, assuming that the links in the network are randomly placed. Efficient
numerical methods for calculating <I> show that as the number of network nodes
N approaches infinity, the quantity N<I> exhibits a discontinuity at parameter
values corresponding to critical RBNs. For finite systems it peaks near the
critical value, but slightly in the disordered regime for typical parameter
variations. The source of high values of N<I> is the indirect correlations
between pairs of elements from different long chains with a common starting
point. The contribution from pairs that are directly linked approaches zero for
critical networks and peaks deep in the disordered regime.


title: GK-dimension of birationally commutative surfaces

abstract:
  Let k be an algebraically closed field, let K/k be a finitely generated field
extension of transcendence degree 2 with automorphism sigma, and let A be an
N-graded subalgebra of Q = K[t; sigma] with A_n finite dimensional over k for
all n. Then if A is big enough in Q in an appropriate sense, we prove that
GKdim A = 3,4,5 or is infinite, with the exact value depending only on the
geometric properties of sigma. The proof uses techniques in the birational
geometry of surfaces which are of independent interest.


title:
Reversal of spin polarization in Fe/GaAs (001) driven by resonant
  surface states: First-principles calculations

abstract:
  A minority-spin resonant state at the Fe/GaAs(001) interface is predicted to
reverse the spin polarization with voltage bias of electrons transmitted across
this interface. Using a Green's function approach within the local spin density
approximation we calculate spin-dependent current in a Fe/GaAs/Cu tunnel
junction as a function of applied bias voltage. We find a change in sign of the
spin polarization of tunneling electrons with bias voltage due to the interface
minority-spin resonance. This result explains recent experimental data on spin
injection in Fe/GaAs contacts and on tunneling magnetoresistance in Fe/GaAs/Fe
magnetic tunnel junctions.


title: Radiative torque alignment: Essential Physical Processes

abstract:
  We study the physical processes that affect the alignment of grains subject
to radiative torques (RATs). To describe the action of RATs, we use the
analytical model (AMO) of RATs introduced in Paper I. We focus our discussion
on the alignment by anisotropic radiation flux with respect to magnetic field,
which defines the axis of grain Larmor precession. Such an alignment does not
invoke paramagnetic dissipation (i.e. Davis-Greenstein mechanism), but,
nevertheless, grains tend to be aligned with long axes perpendicular to the
magnetic field. When we account for thermal fluctuations within grain material,
we show that for grains, which are characterized by a triaxial ellipsoid of
inertia, the zero-$J$ attractor point obtained in our earlier study develops
into a low-$J$ attractor point. We study effects of stochastic gaseous
bombardment and show that gaseous bombardment can drive grains from low-$J$ to
high-$J$ attractor points in cases when the high-$J$ attractor points are
present. As the alignment of grain axes with respect to angular momentum is
higher for higher values of $J$, counter-intuitively, gaseous bombardment can
increase the degree of grain alignment in respect to the magnetic field. We
also study the effects of torques induced by H$_2$ formation and show that they
can change the value of angular momentum at high-$J$ attractor point, but
marginally affect the value of angular momentum at low-$J$ attractor points. We
compare the AMO results with those obtained using the direct numerical
calculations of RATs acting upon irregular grains and validate the use of the
AMO for realistic situations of RAT alignment.


title: Transport quantum logic gates for trapped ions

abstract:
  Many efforts are currently underway to build a device capable of large scale
quantum information processing (QIP). Whereas QIP has been demonstrated for a
few qubits in several systems, many technical difficulties must be overcome in
order to construct a large-scale device. In one proposal for large-scale QIP,
trapped ions are manipulated by precisely controlled light pulses and moved
through and stored in multizone trap arrays. The technical overhead necessary
to precisely control both the ion geometrical configurations and the laser
interactions is demanding. Here we propose methods that significantly reduce
the overhead on laser beam control for performing single and multiple qubit
operations on trapped ions. We show how a universal set of operations can be
implemented by controlled transport of ions through stationary laser beams. At
the same time, each laser beam can be used to perform many operations in
parallel, potentially reducing the total laser power necessary to carry out QIP
tasks. The overall setup necessary for implementing transport gates is simpler
than for gates executed on stationary ions. We also suggest a transport-based
two-qubit gate scheme utilizing microfabricated permanent magnets that can be
executed without laser light.


title: |V_{us}| from Lattice QCD

abstract:
  I review recent progress in calculating |V_{us}| from lattice QCD kaon and
hyperon systems. A preliminary result from the first dynamical calculation in
the hyperon channel is included.


title: T-Anomaly Induced LHC Signals

abstract:
  $\cal T$-parity in the Little Higgs model could be violated by anomalies that
allow the lightest $\cal T$-odd $A_H$ to decay into $ZZ$ and $W^+W^-$. We
analyze these anomaly induced decays and the two-particle and the
three-particle decay modes of other heavy quarks and bosons in this model which
yield unique Large Hadron Collider (LHC) signals with fully reconstructable
events. $\cal T$-odd quarks in the Little Higgs model are nearly degenerate in
mass and they decay by almost identical processes; however, members of the
heavy Higgs triplet follow distinct decay modes. The branching fractions of
three-body decays increase with the global symmetry-breaking energy scale $f$
and are found to be at the level of a few percent in heavy quark decays while
they can reach up to 10% for heavy bosons.


title: Alkali Line Profiles in Degenerate Dwarfs

abstract:
  Ultracool stellar atmospheres show absorption by alkali resonance lines
severely broadened by collisions with neutral perturbers. In the coolest and
densest atmospheres, such as those of T dwarfs, Na I and K I broadened by
molecular hydrogen and helium can come to dominate the entire optical spectrum.
Their profiles have been successfully modelled with accurate interaction
potentials in the adiabatic theory, computing line profiles from the first few
orders of a density expansion of the autocorrelation function. The line shapes
in the emergent spectrum also depend on the distribution of absorbers as a
function of depth, which can be modelled with improved accuracy by new models
of dust condensation and settling.
  The far red K I wings of the latest T dwarfs still show missing opacity in
these models, a phenomenon similar to what has been found for the Na I line
profiles observed in extremely cool, metal-rich white dwarfs. We show that the
line profile in both cases is strongly determined by multiple-perturber
interactions at short distances and can no longer be reproduced by a density
expansion, but requires calculation of the full profile in a unified theory.
Including such line profiles in stellar atmosphere codes will further improve
models for the coolest and densest dwarfs as well as for the deeper atmosphere
layers of substellar objects in general.


title: A Little Twin Higgs Model

abstract:
  We present a twin Higgs model based on left-right symmetry with a tree level
quartic. This is made possible by extending the symmetry of the model to
include two Z_2 parities, each of which is sufficient to protect the Higgs from
getting a quadratically divergent mass squared. Although both parities are
broken explicitly, the symmetries that protect the Higgs from getting a
quadratically divergent mass are broken only collectively. The quadratic
divergences of the Higgs mass are thus still protected at one loop. We find
that the fine tuning in this model is reduced substantially compared to the
original left-right twin Higgs model. This mechanism can also be applied to the
mirror twin Higgs model to get a significant reduction of the fine tuning,
while keeping the mirror photon massless.


title:
Phonon-induced many-body renormalization of graphene electronic
  properties

abstract:
  We develop a theory for the electron-phonon interaction effects on the
electronic properties of graphene. We analytically calculate the electron
self-energy, spectral function and band velocity renormalization due to
phonon-mediated electron-electron interaction. We find that phonon-mediated
electron-electron coupling has a large effect on the graphene band structure
renormalization, and our analytic theory successfully captures the essential
features of the observed graphene electron spectra in the ARPES experiments,
predicting a kink at $\sim 200\mathrm{meV}$ below the Fermi level and a
reduction of the band velocity by $\sim 10-20%$ at the experimental doping
level.


title: A simple shower and matching algorithm

abstract:
  We present a simple formalism for parton-shower Markov chains. As a first
step towards more complete uncertainty bands, we incorporate a comprehensive
exploration of the ambiguities inherent in such calculations. To reduce this
uncertainty, we then introduce a matching formalism which allows a generated
event sample to simultaneously reproduce any infrared safe distribution
calculated at leading or next-to-leading order in perturbation theory, up to
sub-leading corrections. To enable a more universal definition of perturbative
calculations, we also propose a more general definition of the hadronization
cutoff. Finally, we present an implementation of some of these ideas for
final-state gluon showers, in a code dubbed VINCIA.


title:
Self-Dual Yang-Mills Multiplet in Three Dimensions Coupled to
  Supergravity

abstract:
  We couple a recently-established N=1 globally supersymmetric self-dual
Yang-Mills multiplet in three dimensions to supergravity. This becomes possible
due to our previous result on globally supersymmetric formulation based on a
compensator multiplet. We further couple the self-dual vector to a
supersymmetric sigma-model on the coset SO(8,n) / SO(8) X SO(n) via minimal
couplings for an arbitrary gauged subgroup H_0 \subset SO(8) X SO(n). A
corresponding superspace formulation is also presented.


title:
Multiple (inverse) binomial sums of arbitrary weight and depth and the
  all-order epsilon-expansion of generalized hypergeometric functions with one
  half-integer value of parameter

abstract:
  We continue the study of the construction of analytical coefficients of the
epsilon-expansion of hypergeometric functions and their connection with Feynman
diagrams. In this paper, we show the following results:
  Theorem A: The multiple (inverse) binomial sums of arbitrary weight and depth
(see Eq. (1.1)) are expressible in terms of Remiddi-Vermaseren functions.
  Theorem B: The epsilon expansion of a hypergeometric function with one
half-integer value of parameter (see Eq. (1.2)) is expressible in terms of the
harmonic polylogarithms of Remiddi and Vermaseren with coefficients that are
ratios of polynomials. Some extra materials are available via the www at this
http://theor.jinr.ru/~kalmykov/hypergeom/hyper.html


title: The Baum-Connes assembly map and the generalized Bass conjecture

abstract:
  We show that the image of Connes-Karoubi-Chern character, restricted to the
image of the Baum-Connes assembly map in the Bott-periodized topological
K-theory of the complex group algebra, lies in the elliptic summand of the
(periodic) cyclic homology of the group algebra. This implies that for any
(weighted) ell-1 completion of the group algebra, rational surjectivity of the
Baum-Connes assembly map implies the generalized Bass conjecture for that
algebra.


title: Education and Outreach for the Pierre Auger Observatory

abstract:
  The scale and scope of the physics studied at the Auger Observatory offer
significant opportunities for original outreach work. Education, outreach, and
public relations of the Auger collaboration are coordinated in a task of its
own whose goals are to encourage and support a wide range of efforts that link
schools and the public with the Auger scientists and the science of cosmic
rays, particle physics, and associated technologies. This report focuses on the
impact of the collaboration in Mendoza Province, Argentina, as: the Auger
Visitor Center in Malargue that has hosted over 29,000 visitors since 2001, the
Auger Celebration and a collaboration-sponsored science fair held on the
Observatory campus in November 2005, the opening of the James Cronin School in
Malargue in November 2006, public lectures, school visits, and courses for
science teachers. As the collaboration prepares the proposal for the northern
Auger site foreseen to be in southeast Colorado, plans for a comprehensive
outreach program are being developed in parallel, as described here.


title: Pattern Formation without Favored Local Interactions

abstract:
  Individual cellular automata rules are attractive models for a range of
biological and physical self-assembling systems. While coexpression and
coevolution are common in such systems, ensembles of cellular automata rules
remain poorly understood. Here we report the first known analysis of the
equally weighted ensemble of all elementary cellular automata (ECA) rules.
Ensemble dynamics reveal persistent, localized, non-interacting patterns,
rather than homogenization. The patterns are strongly correlated by velocity
and have a quasi-linear dependence on initial conditions. Dispersion from a
single initial site generates peaks traveling at low-denominator fractional
velocities, some of which are not discernible in individual rules, suggesting
collective excitation. Further analysis of the time-evolved rule space shows
the 256 ECA rules can be represented by only approximately 111 principal
components. These results suggest the rather surprising conclusion that rich
self-assembly is possible without favoring particular local interactions.


title:
Relatively hyperbolic groups, rapid decay algebras, and a generalization
  of the Bass conjecture

abstract:
  By deploying dense subalgebras of $\ell^1(G)$ we generalize the Bass
conjecture in terms of Connes' cyclic homology theory. In particular, we
propose a stronger version of the $\ell^1$-Bass Conjecture. We prove that
hyperbolic groups relative to finitely many subgroups, each of which posses the
polynomial conjugacy-bound property and nilpotent periodicity property, satisfy
the $\ell^1$-Stronger-Bass Conjecture. Moreover, we determine the
conjugacy-bound for relatively hyperbolic groups and compute the cyclic
cohomology of the $\ell^1$-algebra of any discrete group.


title:
The Cosmic Ray Observatory Project: A Statewide Outreach and Education
  Experiment in Nebraska

abstract:
  The Cosmic Ray Observatory Project (CROP) is a statewide education and
research experiment involving Nebraska high school students, teachers and
university undergraduates in the study of extensive cosmic-ray air showers. A
network of high school teams construct, install, and operate school-based
detectors in coordination with University of Nebraska physics professors and
graduate students. The detector system at each school is an array of
scintillation counters recycled from the Chicago Air Shower Array in
weather-proof enclosures on the school roof, with a GPS receiver providing a
time stamp for cosmic-ray events. The detectors are connected to triggering
electronics and a data-acquisition PC inside the building. Students share data
via the Internet to search for time coincidences with other sites. Funded by
the National Science Foundation, CROP has enlisted 29 schools with the aim of
expanding to the 314 high schools in the state over several years. This report
highlights both the scientific and professional development achievements of the
project to date.


title: Basic physics of solid materials

abstract:
  Since the cuprate materials behave many curious properties, the mechanism
that causes high-temperature superconductivity in copper oxide materials
(cuprates) has been a controversial topic. To explain these curious properties,
we must look out the physics what these materials include. In this letter, it
is presented that there are the basic physics (1)-(9) in solid materials. I
divide all solid materials into four categories, explain some properties of
them qualitatively, and suggest some ways to turn a solid material into a
superconductor. Particularly, this letter discusses the differences between the
p-type high-Tc cuprate superconductors, the n-type superconductor Nd2-xCexCuO4,
the BCS-superconductor similar MgB2, and heavy Fermions superconductors.


title: Neutrino mixing from the double tetrahedral group T^{\prime}

abstract:
  It is shown that it is possible to create successful models of flavor for
both quarks and leptons using the discrete non-abelian group $T^{\prime}$ by
itself. Two simple realizations are presented that can be used as the starting
point for more general scenarios. In addition to the Minimal Supersymmetric
Standard Model particle content, the models include three generations of right
handed neutrinos and four scalar flavon fields. Three of the flavons are needed
in the quark and charged lepton sector of the models and the fourth flavon
participates only in the neutrino sector.


title: A Model of Neutrino and Higgs Physics at the Electroweak Scale

abstract:
  We present and explore the Higgs physics of a model that in addition to the
Standard Model fields includes a lepton number violating singlet scalar field.
Based on the fact that the only experimental data we have so far for physics
beyond the Standard Model is that of neutrino physics, we impose a constraint
for any addition not to introduce new higher scales. As such, we introduce
right-handed neutrinos with an Electroweak Scale mass. We study the Higgs decay
$H \to \nu \nu$ and show that it leads to different signatures compared to
those in the Standard Model, making it possible to detect them and to probe the
nature of their couplings.


title:
The Laplace transform of the digamma function: an integral due to
  Glasser, Manna and Oloa

abstract:
  We provide an analytic expression for the Laplace transform of the digamma
fuction. This complements work of L. Glasser, D. Manna and O. Oloa on this
question. The Laplace transform is continuous in the Laplace-variable a. The
derivative admits a jump at a= ln 2.


title: High frequency dispersive estimates in dimension two

abstract:
  We prove dispersive estimates at high frequency in dimension two for both the
wave and the Schrodinger groupes for a very large class of real-valued
potentials.


title:
A Comparative Study of Parallel Kinematic Architectures for Machining
  Applications

abstract:
  Parallel kinematic mechanisms are interesting alternative designs for
machining applications. Three 2-DOF parallel mechanism architectures dedicated
to machining applications are studied in this paper. The three mechanisms have
two constant length struts gliding along fixed linear actuated joints with
different relative orientation. The comparative study is conducted on the basis
of a same prescribed Cartesian workspace for the three mechanisms. The common
desired workspace properties are a rectangular shape and given kinetostatic
performances. The machine size of each resulting design is used as a
comparative criterion. The 2-DOF machine mechanisms analyzed in this paper can
be extended to 3-axis machines by adding a third joint.


title: Kinematic Analysis of a New Parallel Machine Tool: the Orthoglide

abstract:
  This paper describes a new parallel kinematic architecture for machining
applications: the orthoglide. This machine features three fixed parallel linear
joints which are mounted orthogonally and a mobile platform which moves in the
Cartesian x-y-z space with fixed orientation. The main interest of the
orthoglide is that it takes benefit from the advantages of the popular PPP
serial machines (regular Cartesian workspace shape and uniform performances) as
well as from the parallel kinematic arrangement of the links (less inertia and
better dynamic performances), which makes the orthoglide well suited to
high-speed machining applications. Possible extension of the orthoglide to
5-axis machining is also investigated.


title:
p-adic Dedekind and Hardy-Berndt type sum related to Volkenborn Integral
  on Z_p

abstract:
  The purpose of this paper is to construct p-adic Dedekind sums and
Hardy-Berndt type sums. We also construct generating function of the twisted
Bernoulli polynomials and functions. Furthermore, we give some discussions on
elliptic analogue of the Apostol-Dedekind sums.


title:
Interactions of a Light Hypersonic Jet with a Non-Uniform Interstellar
  Medium

abstract:
  We present three dimensional simulations of the interaction of a light
hypersonic jet with an inhomogeneous thermal and turbulently supported disk in
an elliptical galaxy. We model the jet as a light, supersonic non-relativistic
flow with parameters selected to be consistent with a relativistic jet with
kinetic power just above the FR1/FR2 break.
  We identify four generic phases in the evolution of such a jet with the
inhomogeneous interstellar medium: 1) an initial ``flood and channel'' phase,
where progress is characterized by high pressure gas finding changing weak
points in the ISM, flowing through channels that form and re-form over time, 2)
a spherical, energy-driven bubble phase, were the bubble is larger than the
disk scale, but the jet remains fully disrupted close to the nucleus, 3) a
rapid, jet break--out phase the where jet breaks free of the last dense clouds,
becomes collimated and pierces the spherical bubble, and 4) a classical phase,
the jet propagates in a momentum-dominated fashion leading to the classical jet
+ cocoon + bow-shock structure.
  Mass transport in the simulations is investigated, and we propose a model for
the morphology and component proper motions in the well-studied Compact
Symmetric Object 4C31.04.


title: Interaction of Jets with the ISM of Radio Galaxies

abstract:
  We present three dimensional simulations of the interaction of a light
hypersonic jet with an inhomogeneous thermal and turbulently supported disk in
an elliptical galaxy, including Radio and multi-band X-ray visualisations.
These simulations are applicable to the GPS/CSS phase of some extragalactic
radio sources.
  We identify four generic phases in the evolution of such a jet with the
interstellar medium. The first is a `flood and channel'' phase, dominated by
complex jet interactions with the dense cloudy medium close to the nucleus. A
spherical, energy driven, bubble phase follows, where the bubble is larger than
the disk scale, but the jet remains fully disrupted close to the nucleus. Then
in a rapid, jet break--out phase, the jet breaks free of the last obstructing
dense clouds, becomes collimated and pierces the more or less spherical bubble.
In the final classical phase, the jet propagates in a momentum-dominated
fashion similar to jets in single component hot haloes, leading to the
classical jet -- cocoon -- bow-shock structure.


title:
Understanding the Characteristics of Internet Short Video Sharing:
  YouTube as a Case Study

abstract:
  Established in 2005, YouTube has become the most successful Internet site
providing a new generation of short video sharing service. Today, YouTube alone
comprises approximately 20% of all HTTP traffic, or nearly 10% of all traffic
on the Internet. Understanding the features of YouTube and similar video
sharing sites is thus crucial to their sustainable development and to network
traffic engineering. In this paper, using traces crawled in a 3-month period,
we present an in-depth and systematic measurement study on the characteristics
of YouTube videos. We find that YouTube videos have noticeably different
statistics compared to traditional streaming videos, ranging from length and
access pattern, to their active life span, ratings, and comments. The series of
datasets also allows us to identify the growth trend of this fast evolving
Internet site in various aspects, which has seldom been explored before. We
also look closely at the social networking aspect of YouTube, as this is a key
driving force toward its success. In particular, we find that the links to
related videos generated by uploaders' choices form a small-world network. This
suggests that the videos have strong correlations with each other, and creates
opportunities for developing novel caching or peer-to-peer distribution schemes
to efficiently deliver videos to end users.


title:
New method for the study of psychotropic drug effects under simulated
  clinical conditions

abstract:
  The sensory contact model allows forming different psychopathological states
(anxious depression, catalepsy, social withdrawal, pathological aggression,
hypersensitivity, cognition disturbances, anhedonia, alcoholism etc.) produced
by repeated agonistic interactions in male mice and investigating the
therapeutic and preventive properties of any drug as well as its efficiency
under simulated clinical conditions. This approach can be useful for a better
understanding of the drugs' action in different stages of disease development
in individuals. It is suggested that this pharmacological approach may be
applied for the screening of different novel psychotropic drugs.


title: Products of irreducible random matrices in the (Max,+) Algebra

abstract:
  We consider the recursive equation ``x(n+1)=A(n)x(n)'' where x(n+1) and x(n)
are column vectors of size k and where A(n) is an irreducible random matrix of
size k x k. The matrix-vector multiplication in the (max,+) algebra is defined
by (A(n)x(n))_i= max_j [ A(n)_{ij} +x(n)_j ]. This type of equation can be used
to represent the evolution of Stochastic Event Graphs which include cyclic
Jackson Networks, some manufacturing models and models with general blocking
(such as Kanban). Let us assume that the sequence (A(n))_n is i.i.d or more
generally stationary and ergodic. The main result of the paper states that the
system couples in finite time with a unique stationary regime if and only if
there exists a set of matrices C such that P {A(0) in C} > 0, and the matrices
in C have a unique periodic regime.