title: Securing U-Healthcare Sensor Networks using Public Key Based Scheme

abstract:
  Recent emergence of electronic culture uplifts healthcare facilities to a new
era with the aid of wireless sensor network (WSN) technology. Due to the
sensitiveness of medical data, austere privacy and security are inevitable for
all parts of healthcare systems. However, the constantly evolving nature and
constrained resources of sensors in WSN inflict unavailability of a lucid line
of defense to ensure perfect security. In order to provide holistic security,
protections must be incorporated in every component of healthcare sensor
networks. This paper proposes an efficient security scheme for healthcare
applications of WSN which uses the notion of public key cryptosystem. Our
entire security scheme comprises basically of two parts; a key handshaking
scheme based on simple linear operations and the derivation of decryption key
by a receiver node for a particular sender in the network. Our architecture
allows both base station to node or node to base station secure communications,
and node-to-node secure communications. We consider both the issues of
stringent security and network performance to propose our security scheme.


title:
Cryptanalysis of Yang-Wang-Chang's Password Authentication Scheme with
  Smart Cards

abstract:
  In 2005, Yang, Wang, and Chang proposed an improved timestamp-based password
authentication scheme in an attempt to overcome the flaws of Yang-Shieh_s
legendary timestamp-based remote authentication scheme using smart cards. After
analyzing the improved scheme proposed by Yang-Wang-Chang, we have found that
their scheme is still insecure and vulnerable to four types of forgery attacks.
Hence, in this paper, we prove that, their claim that their scheme is
intractable is incorrect. Also, we show that even an attack based on Sun et
al._s attack could be launched against their scheme which they claimed to
resolve with their proposal.


title: Properties of nuclear and Coulomb breakup of 8B

abstract:
  The dependence of breakup cross sections of 8B at 65 MeV/nucleon on the
target mass number A_T is investigated by means of the continuum-discretized
coupled-channels method (CDCC) with more reliable distorting potentials than
those in the preceding study. The A_T^(1/3) scaling law of the nuclear breakup
cross section is found to be satisfied only in the middle A_T region of 40 <
A_T < 150. The interference between nuclear and Coulomb breakup amplitudes
vanishes in very forward angle scattering, independently of the target nucleus.
The truncation of the relative energy between the p and 7Be fragments slightly
reduces the contribution of nuclear breakup at very forward angles, while the
angular region in which the first-order perturbation theory works well does not
change essentially.


title: M\'ethode de calcul du rayonnement acoustique de structures complexes

abstract:
  In the automotive industry, predicting noise during design cycle is a
necessary step. Well-known methods exist to answer this issue in low frequency
domain. Among these, Finite Element Methods, adapted to closed domains, are
quite easy to implement whereas Boundary Element Methods are more adapted to
infinite domains, but may induce singularity problems. In this article, the
described method, the SDM, allows to use both methods in their best application
domain. A new method is also presented to solve the SDM exterior problem.
Instead of using Boundary Element Methods, an original use of Finite Elements
is made. Efficiency of this new version of the Substructure Deletion Method is
discussed.


title: A unified approach to compact symmetric spaces of rank one

abstract:
  A relatively simple algebraic framework is given, in which all the compact
symmetric spaces can be described and handled without distinguishing cases. We
also give some applications and further results.


title: A leave-p-out based estimation of the proportion of null hypotheses

abstract:
  In the multiple testing context, a challenging problem is the estimation of
the proportion $\pi_0$ of true-null hypotheses. A large number of estimators of
this quantity rely on identifiability assumptions that either appear to be
violated on real data, or may be at least relaxed. Under independence, we
propose an estimator $\hat{\pi}_0$ based on density estimation using both
histograms and cross-validation. Due to the strong connection between the false
discovery rate (FDR) and $\pi_0$, many multiple testing procedures (MTP)
designed to control the FDR may be improved by introducing an estimator of
$\pi_0$. We provide an example of such an improvement (plug-in MTP) based on
the procedure of Benjamini and Hochberg. Asymptotic optimality results may be
derived for both $\hat{\pi}_0$ and the resulting plug-in procedure. The latter
ensures the desired asymptotic control of the FDR, while it is more powerful
than the BH-procedure. Finally, we compare our estimator of $\pi_0$ with other
widespread estimators in a wide range of simulations. We obtain better results
than other tested methods in terms of mean square error (MSE) of the proposed
estimator. Finally, both asymptotic optimality results and the interest in
tightly estimating $\pi_0$ are confirmed (empirically) by results obtained with
the plug-in MTP.


title: Multiple membrane cavity optomechanics

abstract:
  We investigate theoretically the extension of cavity optomechanics to
multiple membrane systems. We describe such a system in terms of the coupling
of the collective normal modes of the membrane array to the light fields. We
show these modes can be optically addressed individually and be cooled, trapped
and characterized, e.g. via quantum nondemolition measurements. Analogies
between this system and a linear chain of trapped ions or dipolar molecules
imply the possibility of related applications in the quantum regime.


title: Bragg-like curve for dark matter searches; binary gases

abstract:
  The directional detection of low-energy recoil ions can provide strong
possibility for observation of dark matter in the Galaxy. Quenching factors for
5-200 keV recoil ions in N2, CO2, CF4 and CS2 gases are evaluated and
Bragg-like curves, the electronic energy deposition as a function of the
projected range, are presented. The Bragg-like curves are intended for
directional search for the dark matter candidate, WIMPs, using the gas TPC.
Quenching factors for very heavy ions produced in alpha-decay in dry air, N2,
CO2, CF4 and CS2 are also estimated and compared with experimental values.


title:
Large excess of heavy nitrogen in both hydrogen cyanide and cyanogen
  from comet 17P/Holmes

abstract:
  From millimeter and optical observations of the Jupiter-family comet
17P/Holmes performed soon after its huge outburst of October 24, 2007, we
derive 14 N/15N = 139 +/- 26 in HCN, and 14N/15N = 165 +/- 40 in CN,
establishing that HCN has the same non-terrestrial isotopic composition as CN.
The same conclusion is obtained for the long-period comet C/1995 O1 (Hale-Bopp)
after a reanalysis of previously published measurements. These results are
compatible with HCN being the prime parent of CN in cometary atmospheres. The
15N excess relative to the Earth atmospheric value indicates that N-bearing
volatiles in the solar nebula underwent important N isotopic fractionation at
some stage of Solar System formation. HCN molecules never isotopically
equilibrated with the main nitrogen reservoir in the solar nebula before being
incorporated in Oort-cloud and Kuiper-belt comets. The 12C/13C ratios in HCN
and CN are measured to be consistent with the terrestrial value.


title: Spreading Signals in the Wideband Limit

abstract:
  Wideband communications are impossible with signals that are spread over a
very large band and are transmitted over multipath channels unknown ahead of
time. This work exploits the I-mmse connection to bound the achievable
data-rate of spreading signals in wideband settings, and to conclude that the
achievable data-rate diminishes as the bandwidth increases due to channel
uncertainty. The result applies to all spreading modulations, i.e. signals that
are evenly spread over the bandwidth available to the communication system,
with SNR smaller than log(W/L)/(W/L) and holds for communications over channels
where the number of paths L is unbounded by sub-linear in the bandwidth W.


title: On Kaluza-Klein spacetime in Einstein-Gauss-Bonnet gravity

abstract:
  By considering the product of the usual four dimensional spacetime with two
dimensional space of constant curvature, an interesting black hole solution has
recently been found for Einstein-Gauss-Bonnet gravity. It turns out that this
as well as all others could easily be made to radiate Vaidya null dust. However
there exists no Kerr analogue in this setting. To get the physical feel of the
four dimensional black hole spacetimes, we study asymptotic behavior of
stresses at the two ends, $r\to0$ and $r\to\infty$.


title:
Field enhancement factor and field emission from a hemi-ellipsoidal
  metallic needle

abstract:
  We present an exact solution for the electrostatic field between a metallic
hemi-ellipsoidal needle on a plate (as a cathode) and a flat anode. The basic
idea is to replace the cathode by a linearly charged thread in a uniform
electric field and to use a set of "image" charges to reproduce the anode. We
calculate the field enhancement factor on the needle surface and ponderomotive
force acting on the needle. Using the Fowler-Nordheim theory we obtain an exact
analytical formula for the total current.


title: A note on combinatorial splicing formulas for Heegaard Floer homology

abstract:
  We give a precise description of splicing formulas from a previous paper in
terms of knot Floer complex associated with a knot in homology sphere.


title:
Effects of the size of cosmological N-Body simulations on physical
  quantities - III: Skewness

abstract:
  N-Body simulations are an important tool in the study of formation of large
scale structures. Much of the progress in understanding the physics of galaxy
clustering and comparison with observations would not have been possible
without N-Body simulations. Given the importance of this tool, it is essential
to understand its limitations as ignoring these can easily lead to interesting
but unreliable results. In this paper we study the limitations due to the
finite size of the simulation volume. In an earlier work we proposed a
formalism for estimating the effects of a finite box-size on physical
quantities and applied it to estimate the effect on the amplitude of
clustering, mass function. Here, we extend the same analysis and estimate the
effect on skewness and kurtosis in the perturbative regime. We also test the
analytical predictions from the earlier work as well as those presented in this
paper. We find good agreement between the analytical models and simulations for
the two point correlation function and skewness. We also discuss the effect of
a finite box size on relative velocity statistics and find the effects for
these quantities scale in a manner that retains the dependence on the averaged
correlation function.


title:
A search for double beta decays of tin isotopes with enhanced
  sensitivity

abstract:
  A search for the various double beta decay modes of 124Sn and 112Sn has been
performed on 75 kg.days of data. New half-life limits for excited states in
124Sn have been obtained including a lower limit for the decay into the first
excited 2+ state of 124Te of T_half > 0.87e20 yrs (90% CL) and into the first
excited 0+ state of T_half > 1.08e20 yrs (90% CL). Ground state and excited
state transitions of 112Sn have also been experimentally explored. A limit for
the 2 neutrino double electron capture of T_half > 1.8e19 yrs (90% CL) is
obtained. The non-observation of de-excitation gammas from the 0+ at 1888.5keV
results in a lower half-life limit on the 0 neutrino double electron capture
decay of 112Sn of T_half > 0.8e19 yrs (90% CL), despite a possible resonant
enhancement of the decay rate due to degenerated states.


title:
The characteristics of the IR emission features in the spectra of Herbig
  Ae stars: Evidence for chemical evolution

abstract:
  Herbig Ae/Be stars are a class of young pre-main sequence stellar objects of
intermediate mass and are known to have varying amounts of natal cloud material
still present in their direct vicinity. We characterise the IR emission bands,
due to fluorescence by PAH molecules, in the spectra of Herbig Ae/Be stars and
link observed variations to spatial aspects of the mid-IR emission. We analysed
two PAH dominated spectra from a sample of 15 Herbig Ae/Be stars observed with
Spitzer and derive profiles of the major PAH bands. The shape and the measured
band characteristics show pronounced variations between the two Spitzer
spectra. Those variations parallel those found between three ISO spectra of
other, well-studied, Herbig Ae/Be stars. The derived profiles are compared to
those from a broad sample of sources. The Spitzer and ISO spectra exhibit
characteristics commonly interpreted respectively as interstellar matter-like
(ISM), non-ISM-like, or a combination of the two. We argue that the PAH
emission detected from the sources exhibiting a combination of ISM-like and
non-ISM-like characteristics indicates the presence of two dissimilar,
spatially separated, PAH families. As the shape of the individual PAH band
profiles reflects the composition of the PAH molecules involved, this
demonstrates that PAHs in subsequent, evolutionary linked stages of star
formation are different from those in the general ISM, implying active
chemistry. None of the detected PAH emission can be associated with the
(unresolved) disk and is thus associated with the circumstellar cloud. This
implies that chemical changes may already occur in the natal cloud and not
necessarily in the disk.


title: Rewriting Systems in Alternating Knot groups with the Dehn presentation

abstract:
  Every tame, prime and alternating knot is equivalent to a tame, prime and
alternating knot in regular position, with a common projection. In this work,
we show that the Dehn presentation of the knot group of a tame, prime,
alternating knot, with a regular and common projection has a finite and
complete rewriting system. Although there are rules in the rewriting system
with left-hand side a generator and which increase the length of the words we
show that the system is terminating.


title:
Protein Sequencing with an Adaptive Genetic Algorithm from Tandem Mass
  Spectrometry

abstract:
  In Proteomics, only the de novo peptide sequencing approach allows a partial
amino acid sequence of a peptide to be found from a MS/MS spectrum. In this
article a preliminary work is presented to discover a complete protein sequence
from spectral data (MS and MS/MS spectra). For the moment, our approach only
uses MS spectra. A Genetic Algorithm (GA) has been designed with a new
evaluation function which works directly with a complete MS spectrum as input
and not with a mass list like the other methods using this kind of data. Thus
the mono isotopic peak extraction step which needs a human intervention is
deleted. The goal of this approach is to discover the sequence of unknown
proteins and to allow a better understanding of the differences between
experimental proteins and proteins from databases.


title:
A Preliminary Work on Evolutionary Identification of Protein Variants
  and New Proteins on Grids

abstract:
  Protein identification is one of the major task of Proteomics researchers.
Protein identification could be resumed by searching the best match between an
experimental mass spectrum and proteins from a database. Nevertheless this
approach can not be used to identify new proteins or protein variants. In this
paper an evolutionary approach is proposed to discover new proteins or protein
variants thanks a "de novo sequencing" method. This approach has been
experimented on a specific grid called Grid5000 with simulated spectra and also
real spectra.


title: Quantum improvement of time transfer between remote clocks

abstract:
  Exchanging light pulses to perform accurate space-time positioning is a
paradigmatic issue of physics. It is ultimately limited by the quantum nature
of light, which introduces fluctuations in the optical measurements and leads
to the so-called Standard Quantum Limit (SQL). We propose a new scheme
combining homodyne detection and mode-locked femtosecond lasers that lead to a
new SQL in time transfer, potentially reaching the yoctosecond range
(10^-21-10^-24 s). We prove that no other measurement strategy can lead to
better sensitivity with shot noise limited light. We then demonstrate that this
already very low SQL can be overcome using appropriately multimode squeezed
light. Benefitting from the large number of photons used in the experiment and
from the optimal choice of both the detection strategy and of the quantum
resource, the proposed scheme represents a significant potential improvement in
space-time positioning.


title:
Energy deposition in hard dihadron triggered events in heavy-ion
  collisions

abstract:
  The experimental observation of hadrons correlated back-to-back with a
(semi-)hard trigger in heavy ion collisions has revealed a splitting of the
away side correlation structure in a low to intermediate transverse momentum
(P_T) regime. This is consistent with the assumption that energy deposited by
the away side parton into the bulk medium produced in the collision excites a
sonic shockwave (a Mach cone) which leads to away side correlation strength at
large angles. A prediction following from assuming such a hydrodynamical origin
of the correlation structure is that there is a sizeable elongation of the
shockwave in rapidity due to the longitudinal expansion of the bulk medium.
Using a single hadron trigger, this cannot be observed due to the unconstrained
rapidity of the away side parton. Using a dihadron trigger, the rapidity of the
away side parton can be substantially constrained and the longitudinal
structure of the away side correlation becomes accessible. However, in such
events several effects occur which change the correlation structure
substantially: There is not only a sizeable contribution due to the
fragmentation of the emerging away side parton, but also a systematic bias
towards small energy deposition into the medium and hence a weak shockwave. In
this paper, both effects are addressed.


title: Quantitative Theory of a Relaxation Function in a Glass-Forming System

abstract:
  We present a quantitative theory for a relaxation function in a simple
glass-forming model (binary mixture of particles with different interaction
parameters). It is shown that the slowing down is caused by the competition
between locally favored regions (clusters) which are long lived but each of
which relaxes as a simple function of time. Without the clusters the relaxation
of the background is simply determined by one typical length which we deduce
from an elementary statistical mechanical argument. The total relaxation
function (which depends on time in a nontrivial manner) is quantitatively
determined as a weighted sum over the clusters and the background. The
`fragility' in this system can be understood quantitatively since it is
determined by the temperature dependence of the number fractions of the locally
favored regions.


title: Rewriting Systems and Embedding of monoids in groups

abstract:
  In this paper, a connection between rewriting systems and embedding of
monoids in groups is found. We show that if a group with a positive
presentation has a complete rewriting system $\Re$ that satisfies the condition
that each rule in $\Re$ with positive left-hand side has a positive right-hand
side, then the monoid presented by the subset of positive rules from $\Re$
embeds in the group. As an example, we give a simple proof that right angled
Artin monoids embed in the corresponding right angled Artin groups. This is a
special case of the well-known result of Paris \cite{paris} that Artin monoids
embed in their groups.


title: Dyonic Instantons in 5-dim Yang-Mills Chern-Simons Theories

abstract:
  We consider the BPS dyonic instantons in the 5-dim supersymmetric Yang-Mills
Chern-Simons theories. Its field theoretic structures and the moduli space
dynamics in term of the ADHM data have been explored in detail. We find that
the field theoretic Chern-Simons term leads to an effective magnetic field on
instanton moduli space.


title:
Study of B-meson decays to eta_c K^(*), eta_c(2S) K^(*) and eta_c gamma
  K^(*)

abstract:
  We study two-body $B$-meson decays to a charmonium state ($\eta_c$,
$\eta_c(2S)$ or $h_c$) and a $K^+$ or $K^{*0}(892)$ meson using a sample of
$349 fb^{-1}$ of data collected with the BABAR detector at the PEP-II
asymmetric-energy $B$ Factory at SLAC. We measure $BR(B^0\to\eta_c
K^{*0})=(5.7\pm0.6 (stat)\pm0.9 (syst))\times 10^{-4}$, $BR(B^0\to\eta_c(2S)
K^{*0})<3.9\times 10^{-4}$, $BR(B^+\to h_c K^+)\times
BR(h_c\to\eta_c\gamma)<4.8\times 10^{-5}$ and $BR(B^0\to h_c K^{*0})\times
BR(h_c\to\eta_c\gamma)<2.2\times 10^{-4}$ at the 90% C.L., and
$BR(\eta_c(2S)\to K \bar{K} \pi)=(1.9\pm0.4 (stat) \pm1.1 (syst))%$. We also
measure the mass and width of the $\eta_c$ meson to be $m(\eta_c)=(2985.8\pm
1.5(stat) \pm 3.1 (syst)) MeV/c^2$ and $\Gamma(\eta_c)=(36.3^{+3.7}_{-3.6}
(stat) \pm 4.4 (syst)) MeV$.


title:
Application of Gaussian expansion method to nuclear mean-field
  calculations with deformation

abstract:
  We extensively develop a method of implementing mean-field calculations for
deformed nuclei, using the Gaussian expansion method (GEM). This GEM algorithm
has the following advantages: (i) it can efficiently describe the
energy-dependent asymptotics of the wave functions at large $r$, (ii) it is
applicable to various effective interactions including those with finite
ranges, and (iii) the basis parameters are insensitive to nuclide, thereby many
nuclei in wide mass range can be handled by a single set of bases. Superposing
the spherical GEM bases with feasible truncation for the orbital angular
momentum of the single-particle bases, we obtain deformed single-particle
wave-functions to reasonable precision. We apply the new algorithm to the
Hartree-Fock and the Hartree-Fock-Bogolyubov calculations of Mg nuclei with the
Gogny interaction, by which neck structure of a deformed neutron halo is
suggested for $^{40}$Mg.


title:
On the nature of the $\Lambda(1405)$ and $\Lambda(1670)$ from their
  $N_c$ behavior in chiral dynamics

abstract:
  We study the behavior with the number of colors ($N_c$) of the
$\Lambda(1405)$ and $\Lambda(1670)$ resonances obtained dynamically within the
chiral unitary approach. The leading order meson-baryon interaction, used as
the kernel of the unitarization procedure, manifests a nontrivial $N_c$
dependence of the flavor SU(3) representation for baryons. As a consequence,
the SU(3) singlet (or $\bar{K}N$) component of the $\Lambda(1405)$ states
remains bound in the large $N_c$ limit, while the other components dissolve
into the continuum. Introducing explicit SU(3) breaking, we obtain the $N_c$
dependence of the excitation energy, masses and widths of the physical
$\Lambda(1405)$ and $\Lambda(1670)$ resonance. The $N_c$ behavior of the decay
width is found to be different from the general counting rule for a $qqq$
state, indicating the dynamical origin of these resonances.


title:
Ultraviolet behaviour of higher spin gauge field propagators and one
  loop mass renormalization

abstract:
  The ultraviolet singular structure of the bulk-to-bulk propagators for higher
spin gauge fields in $AdS_{4}$ space is analyzed in details. Possible
interactions with the Higgs scalar and the corresponding one loop mass
renormalization are studied. This mass renormalization is finite and connected
with the anomalous dimensions of those currents in the corresponding boundary
$CFT_{3}$ that cease to be conserved when the interaction is switched on. In
particular it is proportional to $\ell-2$.


title: MWC 297: a young high-mass star rotating at critical velocity

abstract:
  MWC 297 is a young massive nearby B[e] star. The central star has a large
projected rotational velocity of 350 km/s. Despite the wealth of published
observations, the nature of this object and its dust-rich surroundings is not
well understood. With the present paper, we shed light on the geometrical
structure of the circumstellar matter which produces the near- to mid-infrared
flux excess, and construct an overall image of the source's appearance and
evolutionary status. The H-, K- and N-band brightness distribution of MWC 297
is probed with the ESO interferometric spectrographs AMBER and MIDI. We have
obtained visibility measurements on 3 AMBER and 12 MIDI baselines, covering a
wide range of spatial frequencies. We have reconstructed the brightness
distribution in H, K and N with a geometric model consisting of three Gaussian
disks with different extent and brightness temperature. This model can account
for the entire near- to mid-IR emission of MWC 297. The near- and mid-IR
emission, including the silicate emission at 10 micron, emanates from a very
compact region (FWHM < 1.5 AU) around the central star. We argue that the
circumstellar matter in the MWC 297 system is organized in a disk, seen under
moderate (i < 40 deg) inclination. The disk displays no inner emission-free gap
at the resolution of our interferometric data. The low inclination of the disk
implies that the actual rotational velocity of the star exceeds its critical
velocity. We discuss the impact of this result in terms of the formation of
high-mass stars, and the main-sequence evolution of classical Be stars.


title:
Quasi-homogeneous linear systems on P2 with base points of multiplicity
  7, 8, 9, 10

abstract:
  In the paper we prove Harbourne-Hirschowitz conjecture for quasi-homogeneous
linear systems on $\mathbb P^2$ for $m=7$, 8, 9, 10, i.e. systems of curves of
given degree passing through points in general position with multiplicities at
least $m,...,m,m_0$, where $m=7$, 8, 9, 10, $m_0$ is arbitrary.


title: New Lower Bounds for the Maximum Number of Runs in a String

abstract:
  We show a new lower bound for the maximum number of runs in a string. We
prove that for any e > 0, (a -- e)n is an asymptotic lower bound, where a =
56733/60064 = 0.944542. It is superior to the previous bound 0.927 given by
Franek et al. Moreover, our construction of the strings and the proof is much
simpler than theirs.


title: Spin-up and hot spots can drive mass out of a binary

abstract:
  The observed distribution of periods and mass ratios of Algols with a B type
primary at birth was updated. Conservative evolution fails to produce the large
fraction with a high mass ratio: i.e. q in [0.4-0.6]. Interacting binaries thus
have to lose mass before or during Algolism. During RLOF mass is transferred
continuously from donor to gainer. The gainer spins up; sometimes up to
critical velocity. Equatorial material on the gainer is therefore less bound to
the system. The material coming from the donor through the first Langrangian
point impinges violently on the surface of the gainer or the edge of the
accretion disc, creating a hot spot in the area of impact. The sum of
rotational energy (fast rotation) and radiative energy (hot spot) depends on
the mass-loss rate. The sum of both energies on a test mass located in the
impact area equals exactly its binding energy at some critical value. As long
as the mass transfer rate is smaller than this value the gainer accepts all the
mass coming from the donor: RLOF happens conservatively. But as soon as the
critical rate is exceeded the gainer will acquire no more than the critical
value and RLOF runs into its liberal era. Low mass binaries never achieve
mass-loss rates larger than the critical value. Intermediate mass binaries
evolve mainly conservatively but mass will be blown away from the system during
the short era of rapid mass transfer soon after RLOF-ignition. Binaries with
9+5.4 solar masses (P in [2-4] d) evolve almost always conservatively. Only
during some 20,000 years the gainer is not capable of grasping all the material
that comes from the donor. During this short lapse of time a significant
fraction of the mass of the system is blown into interstellar space. The mass
ratio bin [0.4-0.6] is now much better represented.


title:
Tunable variation of optical properties of polymer capped gold
  nanoparticles

abstract:
  Optical properties of polymer capped gold nanoparticles of various sizes
(diameter 3-6 nm) have been studied. We present a new scheme to extract size
dependent variation of total dielectric function of gold nanoparticles from
measured UV-Vis absorption data. The new scheme can also be used, in principle,
for other related systems as well. We show how quantum effect, surface atomic
co - ordination and polymer - nanoparticle interface morphology leads to a
systematic variation in inter band part of the dielectric function of gold
nanoparticles, obtained from the analysis using our new scheme. Careful
analysis enables identification of the possible changes to the electronic band
structure in such nanoparticles.


title: Effects of Nitrogen contamination in liquid Argon

abstract:
  A dedicated test of the effects of Nitrogen contamination in liquid Argon has
been performed at the INFN-Gran Sasso Laboratory (LNGS, Italy) within the WArP
R&D program. A detector has been designed and assembled for this specific task
and connected to a system for the injection of controlled amounts of gaseous
Nitrogen into the liquid Argon. Purpose of the test is to detect the reduction
of the Ar scintillation light emission as a function of the amount of the
Nitrogen contaminant injected in the Argon volume. A wide concentration range,
spanning from about 10^-1 ppm up to about 10^3 ppm, has been explored.
Measurements have been done with electrons in the energy range of minimum
ionizing particles (gamma-conversion from radioactive sources). Source spectra
at different Nitrogen contaminations are analyzed, showing sensitive reduction
of the scintillation yield at increasing concentrations. The rate constant of
the light quenching process induced by Nitrogen in liquid Ar has been found to
be k(N2)=0.11 micros^-1 ppm^-1. Direct PMT signals acquisition at high time
resolution by fast Waveform recording allowed to extract with high precision
the main characteristics of the scintillation light emission in pure and
contaminated LAr. In particular, the decreasing behavior in lifetime and
relative amplitude of the slow component is found to be appreciable from O(1
ppm) of Nitrogen concentrations.


title:
Effects of Shear-Induced Crystallization on the Rheology and Ageing of
  Hard Sphere Glasses

abstract:
  The rheological properties of highly concentrated suspensions of hard-sphere
particles are studied with particular reference to the rheological response of
shear induced crystals. Using practically monodisperse hard spheres, we prepare
shear induced crystals under oscillatory shear and examine their linear and
non-linear mechanical response in comparison with their glassy counterparts at
the same volume fraction. It is evident, that shear-induced crystallization
causes a significant drop in the elastic and viscous moduli due to structural
rearrangements that ease flow. For the same reason the critical (peak of G'')
and crossover (overlap of G' and G'') strain are smaller in the crystal
compared to the glass at the same volume fraction. When, however the distance
from the maximum packing in each state is taken into account the elastic
modulus of the crystal is found to be larger than the glass at the same free
volume suggesting a strengthened material due to long range order. Finally,
shear induced crystals counter-intuitively exhibit similar rheological ageing
to the glass (with a logarithmic increase of G'), indicating that the shear
induced structure is not at thermodynamic equilibrium.


title: Conformally flat supergeometry in five dimensions

abstract:
  Using the superspace formulation for the 5D N = 1 Weyl supermultiplet
developed in arXiv:0802.3953, we elaborate the concept of conformally flat
superspace in five dimensions. For a large family of supersymmetric theories
(including sigma-models and Yang-Mills theories) in the conformally flat
superspace, we describe an explicit procedure to formulate their dynamics in
terms of rigid 4D N = 1 superfields. The case of 5D N = 1 anti-de Sitter
superspace is discussed as an example.


title:
A condition for the Bose-Einstein transition in the superfluid liquid
  helium

abstract:
  First, a condition for the Bose-Einstein transition in the superfluid liquid
helium is presented due to the creation of a free neutron spinless pairs in a
liquid helium and a dilute neutron gas mixture. We proposed a new model of
dilute Bose gas, where presence atoms in the condensate is a suppressor for the
collective modes as well as a creator for single-particle excitations On other
hand, it is shown that the terms, of the interaction between the excitations of
the Bose gas and the density modes of the neutron, meditate an attractive
interaction via the neutron modes, which in turn leads to a bound state on a
spinless neutron pair. The lambda transition is defined by a condition for the
Bose-Einstein transition, which transforms reflected neutron pair modes to
single neutron modes.


title: Strong cleanness of matrix rings over commutative rings

abstract:
  Let $R$ be a commutative local ring. It is proved that $R$ is Henselian if
and only if each $R$-algebra which is a direct limit of module finite
$R$-algebras is strongly clean. So, the matrix ring $\mathbb{M}_n(R)$ is
strongly clean for each integer $n>0$ if $R$ is Henselian and we show that the
converse holds if either the residue class field of $R$ is algebraically closed
or $R$ is an integrally closed domain or $R$ is a valuation ring. It is also
shown that each $R$-algebra which is locally a direct limit of module-finite
algebras, is strongly clean if $R$ is a $\pi$-regular commutative ring.


title:
Oxygen contamination in liquid Argon: combined effects on ionization
  electron charge and scintillation light

abstract:
  A dedicated test of the effects of Oxygen contamination in liquid Argon has
been performed at the INFN-Gran Sasso Laboratory (LNGS, Italy) within the WArP
R&D program. Two detectors have been used: the WArP 2.3 lt prototype and a
small (0.7 lt) dedicated detector, coupled with a system for the injection of
controlled amounts of gaseous Oxygen. Purpose of the test with the 0.7 lt
detector is to detect the reduction of the long-lived component lifetime of the
Argon scintillation light emission at increasing O2 concentration. Data from
the WArP prototype are used for determining the behavior of both the ionization
electron lifetime and the scintillation long-lived component lifetime during
the O2-purification process activated in closed loop during the acquisition
run. The electron lifetime measurements allow to infer the O2 content of the
Argon and correlate it with the long-lived scintillation lifetime data. The
effect of Oxygen contamination on the scintillation light has been thus
measured over a wide range of O2 concentration, spanning from about 10^-3 ppm
up to about 10 ppm. The rate constant of the light quenching process induced by
Oxygen in LAr has been found to be k'(O2)=0.54+-0.03 micros^-1 ppm^-1.


title:
The defining characteristics of Intermediate Polars - the case of three
  candidate systems

abstract:
  Intermediate Polars (IPs) are a group of cataclysmic variables (CVs) which
are thought to contain white dwarfs which have a magnetic field strength in the
range ~0.1-10MG. A significant fraction of the X-ray sources detected in recent
deep surveys has been postulated to consist of IPs. Until now two of the
defining characteristics of IPs have been the presence of high (and complex)
absorption in their X-ray spectra and the presence of a stable modulation in
the X-ray light curve which is a signature of the spin period, or the beat
period, of the accreting white dwarf. Three CVs, V426 Oph, EI UMa and LS Peg,
have characteristics which are similar to IPs. However, there has been only
tentative evidence for a coherent period in their X-ray light curve. We present
the results of a search for coherent periods in XMM-Newton data of these
sources using an auto-regressive analysis which models the effects of
red-noise. We confirm the detection of a ~760 sec period in the soft X-ray
light curve of EI UMa reported by Reimer et al and agree that this represents
the spin period. We also find evidence for peaks in the power spectrum of each
source in the range 100-200 sec which are just above the 3sigma confidence
level. We do not believe that they represent genuine coherent modulations.
However, their X-ray spectra are very similar to those of known IPs. We believe
that all three CVs are bona fide IPs. We speculate that V426 Oph and LS Peg do
not show evidence for a spin period since they have closely aligned magnetic
and spin axes. We discuss the implications that this has for the defining
characteristics of IPs.


title: Non-quantum liquefaction of coherent gases

abstract:
  We show that a gas-to-liquid phase transition at zero temperature may occur
in a coherent gas of bosons in the presence of competing nonlinear effects.
This situation can take place both in atomic systems like Bose-Einstein
Condensates in alkalii gases with two and three-body interactions of opposite
signs, as well as in laser beams which propagate through optical media with
Kerr (focusing) and higher order (defocusing) nonlinear responses. The
liquefaction process takes place in absence of any quantum effect and can be
formulated in the frame of a mean field theory, in terms of the minimization of
a thermodynamic potential. We also show numerically that the effect of linear
gain and three-body recombination also provides a rich dynamics with the
emergence of self-organization behaviour.


title: Index of transversally elliptic operators

abstract:
  In 1996, Berline and Vergne gave a cohomological formula for the index of a
transversally elliptic operator. In this paper we propose a new point of view
where the cohomological formulae make use of equivariant Chern characters with
generalized coefficients and with compact suppport. This kind of Chern
characters was studied by the authors in a previous paper (see
arXiv:0801.2822).


title:
Global Properties of the Rich Cluster ABCG 209 at z~0.2. Spectroscopic
  and Photometric Catalogue

abstract:
  This paper is aimed at giving an overview of the global properties of the
rich cluster of galaxies ABCG 209. This is achieved by complementing the
already available data with new medium resolution spectroscopy and NIR
photometry which allow us to i) analyse in detail the cluster dynamics,
distinguishing among galaxies belonging to different substructures and deriving
their individual velocity distributions, using a total sample of 148 galaxies
in the cluster region, of which 134 belonging to the cluster; ii) derive the
cluster NIR luminosity function; iii) study the Kormendy relation and the
photometric plane of cluster early-type galaxies (ETGs). Finally we provide an
extensive photometric (optical and NIR) and spectroscopic dataset for such a
complex system to be used in further analyses investigating the nature,
formation and evolution of rich clusters of galaxies. The observational
scenario confirms that ABCG 209 is presently undergoing strong dynamical
evolution with the merging of two or more subclumps. This interpretation is
also supported by the detection of a radio halo (Giovannini et al. 2006)
suggesting that there is a recent or ongoing merging. Cluster ETGs follow a
Kormendy relation whose slope is consistent with previous studies both at
optical and NIR wavelengths. We investigate the origin of the intrinsic scatter
of the photometric plane due to trends of stellar populations, using line
indices as indicators of age, metallicity and alpha/Fe enhancement. We find
that the chemical evolution of galaxies could be responsible for the intrinsic
dispersion of the Photometric Plane.


title: Transcriptional bursts: a unified model of machines and mechanisms

abstract:
  {\it Transcription} is the process whereby RNA molecules are polymerized by
molecular machines, called RNA polymerase (RNAP), using the corresponding DNA
as the template. Recent {\it in-vivo} experiments with single cells have
established that transcription takes place in "bursts" or "pulses". In this
letter we present a model that captures not only the mechano-chemistry of
individual RNAPs and their steric interactions but also the switching of the
gene between the ON and OFF states. This model accounts for the statistical
properties of the transcriptional bursts. It also shows how the quantitative
features of the distributions of these bursts can be tuned by controlling the
appropriate steps of operation of the RNAP machines.

categories: physics.bio-ph cond-mat.stat-mech q-bio.GN q-bio.SC


title:
Charged Higgs Bosons in the MSSM at CMS: Discovery Reach and Parameter
  Dependence

abstract:
  The search for MSSM Higgs bosons will be an important goal at the LHC. In
order to analyze the search reach of the CMS experiment for the charged MSSM
Higgs bosons, we combine the latest results for the CMS experimental
sensitivities based on full simulation studies with state-of-the-art
theoretical predictions of MSSM Higgs-boson production and decay properties.
The experimental analyses are done assuming an integrated luminosity of 30
fb^-1 for the two cases M_H+- < m_t and M_H+- > m_t. The results are
interpreted as 5 sigma discovery contours in M_H+- - tan_beta planes of the
MSSM for various benchmark scenarios. We study the dependence of the 5 sigma
contours on the variation of the relevant SUSY parameters. Particular emphasis
is put on analyzing the variation of the discovery contours with the Higgs
mixing parameter mu. The variation of mu can shift the prospective discovery
reach in tan_beta by up to Delta tan_beta = 40.


title:
Emergence of product differentiation from consumer heterogeneity and
  asymmetric information

abstract:
  We introduce a fully probabilistic framework of consumer product choice based
on quality assessment. It allows us to capture many aspects of marketing such
as partial information asymmetry, quality differentiation, and product
placement in a supermarket.


title:
Measurement of low energy charge correlations in underdoped spin-glass
  La-based cuprates using impedance spectroscopy

abstract:
  We report on the charge kinetics of La_2CuO_4 lightly doped with Li and Sr.
Impedance spectroscopy measurements down to 25mK and from 20Hz to 500kHz reveal
evidence for low energy charge dynamics, which slow down with decreasing
temperature. Both systems are acutely sensitive to stoichiometry. In the case
of Sr substitution, which at higher carrier concentration evolves to a high
temperature superconductor, the ground state in the pseudogap-doping regime is
one of spatially segregated, dynamic charge domains. The charge carriers slow
down at substantially lower temperatures than their spin counterparts and the
dynamics are particularly sensitive to crystallographic direction. This is
contrasted with the case of Li-doping.


title: Signature of new physics in B -> phi pi decay

abstract:
  We investigate the effect of an extra fourth quark generation and FCNC
mediated $Z$ and $Z'$ bosons on the rare decay mode $B^- \to \phi \pi^-$. In
the standard model, this mode receives only $b \to d$ penguin contributions and
therefore, highly suppressed with branching ratio $\sim 5 \times 10^{-9}$. This
in turn makes this mode a very sensitive probe for new physics. We find that
due to the above mentioned new physics contributions there is a significant
enhancement in its branching ratio. Furthermore, the direct CP violation
parameter which is identically zero in the SM is found to be quite significant.
If this mode will be observed in the upcoming LHCb experiment, it will not only
provide a clear signal of new physics but also can be used to constrain the new
physics parameter space.


title:
Models of the iron K_alpha fluorescence line and the Compton shoulder in
  irradiated accretion disk spectra

abstract:
  We present a full set of model atmosphere equations for the accretion disk
around a supermassive black hole irradiated by hard X-ray lamp of power-law
spectral distribution. Model equations allow for multiple Compton scattering of
radiation on free electrons, and for large relative photon-electron energy
exchange at the time of scattering. We present spectra in specific intensities
integrated over the disk surface. Theoretical outgoing intensity spectra show
soft X-ray excess below 1 keV, and distinct K_alpha and K_beta fluorescent
lines of iron. We demonstrate the existence of the Compton Shoulder and claim
that it can contribute to the asymmetry and equivalent widths of some observed
Fe K_alpha lines in AGN. Our models exhibit the effect of limb-brightening in
reflected X-rays.


title:
Transition metal dimers as potential molecular magnets: A challenge to
  computational chemistry

abstract:
  Dimers are the smallest chemical objects that show magnetic anisotropy. We
focus on 3$d$ and 4$d$ transition metal dimers that have magnetic ground states
in most cases. Some of these magnetic dimers have a considerable barrier
against re-orientation of their magnetization, the so-called magnetic
anisotropy energy, MAE. The height of this barrier is important for
technological applications, as it determines, e.g., the stability of
information stored in magnetic memory devices. It can be estimated by means of
relativistic density functional calculations. Our approach is based on a
full-potential local-orbital method (FPLO) in a four-component Dirac-Kohn-Sham
implementation. Orbital polarization corrections to the local density
approximation are employed. They are discussed in the broader context of
orbital dependent density functionals. Ground state properties (spin
multiplicity, bond length, harmonic vibrational frequency, spin- and orbital
magnetic moment, and MAE) of the 3$d$ and 4$d$ transition metal dimers are
evaluated and compared with available experimental and theoretical data. We
find exceptionally high values of MAE, close to 0.2 eV, for four particular
dimers: Fe$_2$, Co$_2$, Ni$_2$, and Rh$_2$.


title: Interpolating Dispersionless Integrable System

abstract:
  We introduce a dispersionless integrable system which interpolates between
the dispersionless Kadomtsev-Petviashvili equation and the hyper-CR equation.
The interpolating system arises as a symmetry reduction of the anti--self--dual
Einstein equations in (2, 2) signature by a conformal Killing vector whose
self--dual derivative is null. It also arises as a special case of the
Manakov-Santini integrable system. We discuss the corresponding Einstein--Weyl
structures.


title: Real Elements in Spin Groups

abstract:
  Let $F$ be a field of characteristic $\neq 2$. Let $G$ be an algebraic group
defined over $F$. An element $t\in G(F)$ is called {\bf real} if there exists
$s\in G(F)$ such that $sts^{-1}=t^{-1}$. A semisimple element $t$ in $GL_n(F),
SL_n(F), O(q), SO(q), Sp(2n)$ and the groups of type $G_2$ over $F$ is real if
and only if $t=\tau_1\tau_2$ where $\tau_1^2=\pm 1=\tau_2^2$ (ref.
\cite{st1,st2}). In this paper we extend this result to the semisimple elements
in $Spin$ groups when $\dim(V)\equiv 0,1,2 \imod 4$.


title: Phase diagram of Fe-doped Ni-Mn-Ga ferromagnetic shape-memory alloys

abstract:
  We have studied the effect of Fe addition on the structural and magnetic
transitions in the magnetic shape memory alloy Ni-Mn-Ga by substituting
systematically each atomic species by Fe. Calorimetric and AC susceptibility
measurements have been carried out in order to study the magnetic and
structural transformation properties. We find that the addition of Fe modifies
the structural and magnetic transformation temperatures. Magnetic transition
temperatures are displaced to higher values when Fe is substituted into
Ni-Mn-Ga, while martensitic and premartensitic transformation temperatures
shift to lower values. Moreover, it has been found that the electron per atom
concentration essentially governs the phase stability in the quaternary system.
However, the observed scaling of transition temperatures with $e/a$ differs
from that reported in the related ternary system Ni-Mn-Ga.


title:
Weak interaction corrections to hadronic top quark pair production:
  contributions from quark-gluon and $b \bar b$ induced reactions

abstract:
  As an addendum to our previous evaluation of the weak-interaction corrections
to hadronic top-quark pair production we determine the leading weak-interaction
contributions due to the subprocesses $b {\bar b} \to t {\bar t}$ and $g q
({\bar q}) \to t {\bar t} q ({\bar q})$. For several distributions in $t {\bar
t}$ production at the LHC we find that these contributions are non-negligible
as compared to the weak corrections from the other partonic subprocesses.


title: Convective intensification of magnetic fields in the quiet Sun

abstract:
  Kilogauss-strength magnetic fields are often observed in intergranular lanes
at the photosphere in the quiet Sun. Such fields are stronger than the
equipartition field $B_e$, corresponding to a magnetic energy density that
matches the kinetic energy density of photospheric convection, and comparable
with the field $B_p$ that exerts a magnetic pressure equal to the ambient gas
pressure. We present an idealised numerical model of three-dimensional
compressible magnetoconvection at the photosphere, for a range of values of the
magnetic Reynolds number. In the absence of a magnetic field, the convection is
highly supercritical and is characterised by a pattern of vigorous,
time-dependent, ``granular'' motions. When a weak magnetic field is imposed
upon the convection, magnetic flux is swept into the convective downflows where
it forms localised concentrations. Unless this process is significantly
inhibited by magnetic diffusion, the resulting fields are often much greater
than $B_e$, and the high magnetic pressure in these flux elements leads to
their being partially evacuated. Some of these flux elements contain
ultra-intense magnetic fields that are significantly greater than $B_p$. Such
fields are contained by a combination of the thermal pressure of the gas and
the dynamic pressure of the convective motion, and they are constantly
evolving. These ultra-intense fields develop owing to nonlinear interactions
between magnetic fields and convection; they cannot be explained in terms of
``convective collapse'' within a thin flux tube that remains in overall
pressure equilibrium with its surroundings.


title:
High Temperature Superconductivity in Transition Metal Oxypnictides: a
  Rare-Earth Puzzle?

abstract:
  We have performed an extensive ab initio LDA and LSDA+U calculations of
electronic structure of newly discovered high-temperature superconducting
series ReO(1-x)F(x)FeAs (Re=La,Ce, Pr, Nd, Sm and hypothetical case of Re=Y).
In all cases we obtain almost identical electronic spectrum (both energy
dispersions and the densities of states) in rather wide energy interval (about
2 eV) around the Fermi level. We also debate that this fact is unlikely to be
changed by the account of strong correlations. It leads inevitably to the same
critical temperature Tc of superconducting transition in any theoretical
BCS-like mechanism of Cooper pair formation. We argue that the experimentally
observed variations of Tc for different rare-earth substitutions are either due
to disorder effects or less probably because of possible changes in
spin-fluctuation spectrum of FeAs layers caused by magnetic interactions with
rare-earth spins in ReO layers.


title: Classifying foliations

abstract:
  We give a survey of the approaches to classifying foliations, starting with
the Haefliger classifying spaces and the various results and examples about the
secondary classes of foliations. Various dynamical properties of foliations are
introduced and discussed, including expansion rate, local entropy, and orbit
growth rates. This leads to a decomposition of the foliated space into Borel or
measurable components with these various dynamical types. The dynamical
structure is compared with the classification via secondary classes.


title: Four loop MSbar mass anomalous dimension in the Gross-Neveu model

abstract:
  We compute the four loop term of the mass anomalous dimension in the two
dimensional Gross-Neveu model in the MSbar scheme. The absence of
multiplicative renormalizability which results when using dimensional
regularization means that the effect of the evanescent operator, which first
appears at three loops in the 4-point Green's function, has to be properly
treated in the construction of the renormalization group function. We repeat
the calculation of the three loop MSbar beta-function and construct the
beta-function of the evanescent operator coupling which corrects earlier
computations.


title: Divergence form operators in Reifenberg flat domains

abstract:
  We study the boundary regularity of solutions of elliptic operators in
divergence form with $C^{0,\alpha}$ coefficients or operators which are small
perturbations of the Laplacian in non-smooth domains. We show that, as in the
case of the Laplacian, there exists a close relationship between the regularity
of the corresponding elliptic measure and the geometry of the domain.


title: Reality Properties of Conjugacy Classes in G_2

abstract:
  Let $G$ be an algebraic group over a field $k$. We call $g\in G(k)$ {\bf
real} if $g$ is conjugate to $g^{-1}$ in $G(k)$. In this paper we study reality
for groups of type $G_2$ over fields of characteristic different from 2. Let
$G$ be such a group over $k$. We discuss reality for both semisimple and
unipotent elements. We show that a semisimple element in $G(k)$ is real if and
only if it is a product of two involutions in $G(k)$. Every unipotent element
in $G(k)$ is a product of two involutions in $G(k)$. We discuss reality for
$G_2$ over special fields and construct examples to show that reality fails for
semisimple elements in $G_2$ over $\Q$ and $\Q_p$. We show that semisimple
elements are real for $G_2$ over $k$ with $cd(k)\leq 1$. We conclude with
examples of nonreal elements in $G_2$ over $k$ finite, with characteristic $k$
not 2 or 3, which are not semisimple or unipotent.


title:
Geometric Data Analysis, From Correspondence Analysis to Structured Data
  Analysis (book review)

abstract:
  Review of: Brigitte Le Roux and Henry Rouanet, Geometric Data Analysis, From
Correspondence Analysis to Structured Data Analysis, Kluwer, Dordrecht, 2004,
xi+475 pp.


title: Reality Properties of Conjugacy Classes in algebraic Groups

abstract:
  Let $G$ be an algebraic group defined over a field $k$. We call $g\in G$ {\bf
real} if $g$ is conjugate to $g^{-1}$ and $g\in G(k)$ as {\bf $k$-real} if $g$
is real in $G(k)$. An element $g\in G$ is {\bf strongly real} if $\exists h\in
G$, $h^{2}=1$ (i.e. $h$ is an {\bf involution}) such that $hgh^{-1}=g^{-1}$.
Clearly, strongly real elements are real and are product of two involutions.
Let $G$ be a connected adjoint semisimple group over a perfect field $k$, with
-1 in the Weyl group. We prove that any strongly regular $k$-real element in
$G(k)$ is strongly $k$-real (i.e. is a product of two involutions in $G(k)$).
For classical groups, with some mild exceptions, over an arbitrary field $k$ of
characteristic not 2, we prove that $k$-real semisimple elements are strongly
$k$-real. We compute an obstruction to reality and prove some results on
reality specific to fields $k$ with $cd(k)\leq 1$. Finally, we prove that in a
group $G$ of type $G_2$ over $k$, characteristic of $k$ different from 2 and 3,
any real element in $G(k)$ is strongly $k$-real. This extends our results in
\cite{st}, on reality for semisimple and unipotent real elements in groups of
type $G_2$.


title:
Comment on: Quantum interference of tunnel trajectories between states
  of different spin length in a dimeric molecular nanomagnet

abstract:
  Ramsey et al. [Nature Phys. 4, 277-281 (2008)] report the observation of
quantum interference associated with tunnelling trajectories between states of
different total spin length in a dimeric molecular nanomagnet. They argue that
the interference is a consequence of the unique characteristics of a molecular
Mn12 wheel, which behaves as a molecular dimer with weak ferromagnetic exchange
coupling.
  We show here that the data published by Ramsey et al. are not consistent and
unfortunately mostly wrong. We show further that the Landau-Zener (LZ) formula,
which links the tunnel probability with the tunnel splitting, can only be
applied in a well-defined experimental region, which lays outside the region
accessed by Ramsey and colleagues. Only a lower-limit estimate of the tunnel
splitting can be obtained, showing that the observed transition cannot be
explained with the dimer model. We also present other shortcomings of the paper
questioning the dimer model, and that the alignment of the magnetic field is
crucial for observing quantum interference.


title: Quartic quantum theory: an extension of the standard quantum mechanics

abstract:
  We propose an extended quantum theory, in which the number K of parameters
necessary to characterize a quantum state behaves as fourth power of the number
N of distinguishable states. As the simplex of classical N-point probability
distributions can be embedded inside a higher dimensional convex body of mixed
quantum states, one can further increase the dimensionality constructing the
set of extended quantum states. The embedding proposed corresponds to an
assumption that the physical system described in N dimensional Hilbert space is
coupled with an auxiliary subsystem of the same dimensionality. The extended
theory works for simple quantum systems and is shown to be a non-trivial
generalisation of the standard quantum theory for which K=N^2. Imposing certain
restrictions on initial conditions and dynamics allowed in the quartic theory
one obtains quadratic theory as a special case. By imposing even stronger
constraints one arrives at the classical theory, for which K=N.


title: WEAKLY-coupled IIA Flux Compactifications

abstract:
  We study compactifications of type IIA string theory on Calabi-Yau manifolds
that are mirror to a subset of the type IIB LARGE-volume models. A combination
of flux, alpha' corrections and non-perturbative effects stabilises the moduli
in a non-supersymmetric AdS vacuum. This vacuum has the feature that the
(ten-dimensional) string coupling is exponentially small which can naturally
lead to a TeV supersymmetry breaking scale with an intermediate string scale.
The AdS vacuum can be uplifted to a dS one through the introduction of D6
branes, and complex-structure modular inflation can be realised.


title: Using spin bias to manipulate and measure quantum spin in quantum dots

abstract:
  A double-quantum-dot coupled to electrodes with spin-dependent splitting of
chemical potentials (spin bias) is investigated theoretically by means of the
Green's functions formalism. By applying a large spin bias, the quantum spin in
a quantum dot (the dot 1) can be manipulated in a fully electrical manner. To
noninvasively monitor the manipulation of the quantum spin in the dot 1, it is
proposed that the second quantum dot (the dot 2) is weakly coupled to the dot
1. In the presence of the exchange interaction between the two dots, the
polarized spin in the dot 1 behaves like an effective magnetic field and weakly
polarizes the spin in the nearby quantum dot 2. By applying a very small spin
bias to the dot 2, the spin-dependent transport through the dot 2 can be
probed, allowing the spin polarization in the dot 1 to be identified
nondestructively. These two steps form a complete scheme to manipulate a
trapped spin while permitting this manipulation to be monitored in the
double-dot system using pure electric approaches.


title: Lattice results on gluon and ghost propagators in Landau gauge

abstract:
  We present clear evidence of strong effects of Gribov copies in Landau gauge
gluon and ghost propagators computed on the lattice at small momenta by
employing a new approach to Landau gauge fixing and a more effective numerical
algorithm. It is further shown that the new approach substantially decreases
notorious finite-volume effects.


title: Modified symplectic structures in cotangent bundles of Lie groups

abstract:
  In earlier work (*) we studied an extension of the canonical symplectic
structure in the cotangent bundle of an affine space ${\cal Q}={\bf R}^N$, by
additional terms implying the Poisson non-commutativity of both configuration
and momentum variables. In this article, we claim that such an extension can be
done consistently when ${\cal Q}$ is a Lie group $G$. -- (*) : F.J.Vanhecke,
C.Sigaud and A.R.da Silva, arXiv:math-phys/0502003 and Braz.J.Phys.{\bf 36},no
IB,194(2006)


title:
Stop-antistop and sbottom-antisbottom production at LHC: a one-loop
  search for model parameters dependence

abstract:
  We have computed the one-loop electroweak expression of diagonal and non
diagonal stop-antistop and sbottom-antisbottom production from initial state
gluons at LHC. We have investigated the possibility that the one-loop effects
exhibit a dependence on "extra" supersymmetric parameters different from the
final squark masses. Our results, given for a choice of twelve SUSY benchmark
points in the MSSM with mSUGRA symmetry breaking, show that in some cases a
mild dependence might arise, at the percent relative level, of not simple
experimental detection.


title:
The stellar population of the Rosat North Ecliptic Pole survey. II.
  Spectral analysis

abstract:
  X-ray surveys allow to identify young, main-sequence stars in the solar
neighborhood. Young, stellar samples, selected according to their activity, can
be used to determine the stellar birthrate in the last billion years. The ROSAT
North Ecliptic Pole survey (NEP), with its moderately deep sensitivity (fluxes
~10^(-14) erg cm^(-2) sec^(-1)), is the best survey, to date, able to sample
the intermediate-age (10^8 - 10^9 years) nearby population. The identification
process of NEP X-ray sources resulted in 144 X-ray sources having a normal
stellar counterpart, with an excess of yellow stars with respect to model
predictions. We want to determine if these X-ray active stars are young or
intermediate-age stars, or active binaries. We acquired high-resolution, high
signal-to-noise ratio optical spectra, to determine the age and physical
properties of the NEP X-ray-detected stellar sources. We measure the (i)
lithium abundance using the Li I 6707.8 angstrom line, which is an excellent,
youth indicator for our age range of interest; (ii) rotational and radial
velocities (through cross-correlation methods); and (iii) chromospheric
emission. The radial velocities distribution is consistent with that of a young
field star population of age 4x10^9 yrs, or younger. Rotational velocity
measurements imply that our sample is dominated by relatively young or
intermediate-age stars, as confirmed by our lithium measurements. Most of the
detected stars probably belong to a young or intermediate-age population. Our
measurements suggest that a burst in the stellar birthrate of a factor of four
occurred in the last 10^8 years. We cannot, however, exclude the possibility
that a small fraction of sources, amongst the fastest of the K-rotators, are
old binary systems with tidally-locked rotation.


title: Groebner-Shirshov Bases for Lie Algebras: after A. I. Shirshov

abstract:
  In this paper, we review Shirshov's method for free Lie algebras invented by
him in 1962 which is now called the Groebner-Shirshov bases theory.


title:
Quantum corrections to static solutions of phi-in-quadro and Sin-Gordon
  models via generalized zeta-function

abstract:
  A general algebraic method of quantum corrections evaluation is presented.
Quantum corrections to a few classical solutions (kinks and periodic) of
Ginzburg-Landau (phi-in-quadro) and Sin-Gordon models are calculated in
arbitrary dimensions. The Green function for heat equation with a soliton
potential is constructed by means of Laplace transformation theory and Hermit
equation for the Green function transform. The generalized zeta-function is
used to evaluate the functional integral and quantum corrections to mass in
quasiclassical approximation.


title: M2-branes on M-folds

abstract:
  We argue that the moduli space for the Bagger-Lambert A_4 theory at level k
is (R^8 \times R^8)/D_{2k}, where D_{2k} is the dihedral group of order 4k. We
conjecture that the theory describes two M2-branes on a Z_{2k} ``M-fold'', in
which a geometrical action of Z_{2k} is combined with an action on the branes.
For k=1, this arises as the strong coupling limit of two D2-branes on an O2^-
orientifold, whose worldvolume theory is the maximally supersymmetric SO(4)
gauge theory. Finally, in an appropriate large-k limit we show that one
recovers compactified M-theory and the M2-branes reduce to D2-branes.


title:
Young Globular Clusters in an old S0: Clues to the Formation History of
  NGC 4570

abstract:
  We here present our first attempt to use Globular Clusters as tracers of
their parent galaxy's formation history. Globular Cluster Systems of most
early-type galaxies feature two peaks in their optical colour distributions.
Blue-peak Globular Clusters are generally believed to be old and metal-poor.
The ages, metallicities, and the origin of the red-peak Globular Clusters are
being debated. We here present our analysis of the ages and metallicities of
the red peak Globular Clusters in the Virgo S0 NGC 4570 using deep Ks-band
photometry from NTT/SOFI (ESO program ID 079.B-0511) for the red-peak Globular
Clusters in combination with HST-ACS archival data to break the age-metallicity
degeneracy.
  We analyze the combined g, z, and Ks spectral energy distribution by
comparison with a large grid of GALEV evolutionary synthesis models for star
clusters with different ages and metallicities. This analysis reveals a
substantial population of intermediate-age (1-3 Gyr) and metal-rich (solar
metallicity) Globular Clusters. We discuss their age and metallicity
distributions together with information on the parent galaxy from the
literature to gain insight into the formation history of this galaxy.
  Our results prove the power of this approach to reveal the (violent) star
formation and chemical enrichment histories of galaxies on the basis of
combined optical and near-infrared photometry.


title: Cohomology of Oriented Tree Diagram Lie Algebras

abstract:
  Xu introduced a family of root-tree-diagram nilpotent Lie algebras of
differential operators, in connection with evolution partial differential
equations. We generalized his notion to more general oriented tree diagrams.
These algebras are natural analogues of the maximal nilpotent Lie subalgebras
of finite-dimensional simple Lie algebras. In this paper, we use Hodge
Laplacian to study the cohomology of these Lie algebras. The "total rank
conjecture" and "$b_2$-conjecture" for the algebras are proved. Moreover, we
find the generating functions of the Betti numbers by means of Young tableaux
for the Lie algebras associated with certain tree diagrams of single branch
point. By these functions and Euler-Poincare principle, we obtain analogues of
the denominator identity for finite-dimensional simple Lie algebras. The result
is a natural generalization of the Bott's classical result in the case of
special linear Lie algebras.


title: Induced Gauge Theory on a Noncommutative Space

abstract:
  We discuss the calculation of the 1-loop effective action on four
dimensional, canonically deformed Euclidean space. The theory under
consideration is a scalar $\phi^4$ model with an additional oscillator
potential. This model is known to be re normalisable. Furthermore, we couple an
exterior gauge field to the scalar field and extract the dynamics for the gauge
field from the divergent terms of the 1-loop effective action using a matrix
basis. This results in proposing an action for noncommutative gauge theory,
which is a candidate for a renormalisable model.


title:
Cross-sections for nuclide production in 56Fe target irradiated by 300,
  500,750, 1000, 1500, and 2600 MeV protons compared with data on hydrogen
  target irradiation by 300, 500, 750, 1000, and 1500 MeV/nucleon 56Fe ions

abstract:
  Cross-sections for radioactive nuclide production in 56Fe(p,x) reactions at
300, 500, 750, 1000, 1500, and 2600 MeV were measured using the ITEP U-10
proton accelerator. In total, 221 independent and cumulative yields of products
of half-lives from 6.6 min to 312 days have been obtained via the
direct-spectrometry method. The measured data have been compared with the
experimental data obtained elsewhere by the direct and inverse kinematics
methods and with calculations by 15 codes, namely: MCNPX (INCL, CEM2k, BERTINI,
ISABEL), LAHET (BERTINI, ISABEL), CEM03 (.01, .G1, .S1), LAQGSM03 (.01, .G1,
>.S1), CASCADE-2004, LAHETO, and BRIEFF. Most of our data are in a good
agreement with the inverse kinematics results and disprove the results of some
earlier activation measurements that were quite different from the inverse
kinematics measurements. The most significant calculation-to-experiment
differences are observed in the yields of the A<30 light nuclei, indicating
that further improvements in nuclear reaction models are needed, and pointing
out as well to a necessity of more complete measurements of such reactions.


title: Experimental quantum information processing with 43Ca+ ions

abstract:
  For quantum information processing (QIP) with trapped ions, the isotope 43Ca+
offers the combined advantages of a quantum memory with long coherence time, a
high fidelity read out and the possibility of performing two qubit gates on a
quadrupole transition with a narrow-band laser. Compared to other ions used for
quantum computing, 43Ca+ has a relatively complicated level structure. In this
paper we discuss how to meet the basic requirements for QIP and demonstrate
ground state cooling, robust state initialization and efficient read out for
the hyperfine qubit with a single 43Ca+ ion. A microwave field and a Raman
light field are used to drive qubit transitions, and the coherence times for
both fields are compared. Phase errors due to interferometric instabilities in
the Raman field generation do not limit the experiments on a time scale of 100
ms. We find a quantum information storage time of many seconds for the
hyperfine qubit.


title:
Electronic and magnetic properties of K$_{2}$CuP$_{2}$O$_{7}$ - a model
  S=1/2 Heisenberg chain system

abstract:
  The electronic and magnetic properties of K$_{2}$CuP$_{2}$O$_{7}$ were
investigated by means of susceptibility, specific heat and $^{31}$P nuclear
magnetic resonance (NMR) measurements and by LDA band structure calculations.
The temperature dependence of the NMR shift $K(T)$ is well described by the
$S=1/2$ Heisenberg antiferromagnetic chain (HAF) model with nearest neighbor
exchange $J_{1}$ $\simeq $ $(141\pm 5)$ K. The corresponding mapping of an
LDA-derived tight-binding model leads to $J_{1}^{LDA}$ $\simeq$ 196 K. The spin
lattice relaxation rate $1/T_{1}$ decreases with temperature below 300 K but
becomes nearly temperature independent between 30 K and 2 K as theoretically
expected for an $S = {1/2}$ HAF chain. None of the investigated properties give
any evidence for long range magnetic order above 2K, in agreement with the
results of the band structure calculation, which yield extremely weak exchange
to the next nearest neighbor (NNN) and a very small and frustrated inter-chain
exchange. Thus, K$_{2}$CuP$_{2}$O$_{7}$ seems to be a better realization of a
nearest neighbor $S = {1/2}$ HAF chain than the compounds reported so far.


title: Chaining Techniques and their Application to Stochastic Flows

abstract:
  We review several competing chaining methods to estimate the supremum, the
diameter of the range or the modulus of continuity of a stochastic process in
terms of tail bounds of their two-dimensional distributions. Then we show how
they can be applied to obtain upper bounds for the growth of bounded sets under
the action of a stochastic flow.


title: Abelian Ideals and Cohomology of Symplectic Type

abstract:
  For symplectic Lie algebras $\mathfrak{sp}(2n,\mathbb{C})$, denote by
$\mathfrak{b}$ and $\mathfrak{n}$ its Borel subalgebra and maximal nilpotent
subalgebra, respectively. We construct a relationship between the abelian
ideals of $\mathfrak{b}$ and the cohomology of $\mathfrak{n}$ with trivial
coefficients. By this relationship, we can enumerate the number of abelian
ideals of $\mathfrak{b}$ with certain dimension via the Poincare polynomials of
Weyl groups of type $A_{n-1}$ and $C_n$.


title:
Correlative signatures of heavy Majorana neutrinos and doubly-charged
  Higgs bosons at the Large Hadron Collider

abstract:
  We explore an intriguing possibility to test the type-II seesaw mechanism of
neutrino mass generation at the Large Hadron Collider (LHC). We show that the
lepton-number-violating signatures of heavy Majorana neutrinos N_i (for i=1, 2,
3) and doubly-charged Higgs bosons H^++(H^--) can be closely correlated with
each other in a class of TeV-scale type-II seesaw models. Taking the minimal
version of such models for example, we calculate the cross sections of pp ->
l^+_\alpha l^+_\beta X (l^-_\alpha l^-_\beta X) processes mediated separately
by N_1 and H^++(H^--), and illustrate their nontrivial correlation at the LHC.


title: Immune System Approaches to Intrusion Detection - A Review

abstract:
  The use of artificial immune systems in intrusion detection is an appealing
concept for two reasons. Firstly, the human immune system provides the human
body with a high level of protection from invading pathogens, in a robust,
self-organised and distributed manner. Secondly, current techniques used in
computer security are not able to cope with the dynamic and increasingly
complex nature of computer systems and their security. It is hoped that
biologically inspired approaches in this area, including the use of
immune-based systems will be able to meet this challenge. Here we review the
algorithms used, the development of the systems and the outcome of their
implementation. We provide an introduction and analysis of the key developments
within this field, in addition to making suggestions for future research.


title: Singular cobordism categories

abstract:
  Recently Galatius, Madsen, Tillmann and Weiss identified the homotopy type of
the classifying space of the cobordism category of embedded d-dimensional
manifolds [7] for each positive integer d. Their result lead to a new proof of
the generalized standard Mumford conjecture. We extend the main theorem of [7]
to the case of cobordism categories of embedded d-dimensional manifolds with
prescribed singularities, and explain the relation of singular cobordism
categories to the bordism version of the Gromov h-principle.


title: k-Wise Independent Random Graphs

abstract:
  We study the k-wise independent relaxation of the usual model G(N,p) of
random graphs where, as in this model, N labeled vertices are fixed and each
edge is drawn with probability p, however, it is only required that the
distribution of any subset of k edges is independent. This relaxation can be
relevant in modeling phenomena where only k-wise independence is assumed to
hold, and is also useful when the relevant graphs are so huge that handling
G(N,p) graphs becomes infeasible, and cheaper random-looking distributions
(such as k-wise independent ones) must be used instead. Unfortunately, many
well-known properties of random graphs in G(N,p) are global, and it is thus not
clear if they are guaranteed to hold in the k-wise independent case. We explore
the properties of k-wise independent graphs by providing upper-bounds and
lower-bounds on the amount of independence, k, required for maintaining the
main properties of G(N,p) graphs: connectivity, Hamiltonicity, the
connectivity-number, clique-number and chromatic-number and the appearance of
fixed subgraphs. Most of these properties are shown to be captured by either
constant k or by some k= poly(log(N)) for a wide range of values of p, implying
that random looking graphs on N vertices can be generated by a seed of size
poly(log(N)). The proofs combine combinatorial, probabilistic and spectral
techniques.


title: A generalized voter model on complex networks

abstract:
  We study a generalization of the voter model on complex networks, focusing on
the scaling of mean exit time. Previous work has defined the voter model in
terms of an initially chosen node and a randomly chosen neighbor, which makes
it difficult to disentangle the effects of the stochastic process itself
relative to the network structure. We introduce a process with two steps, one
that selects a pair of interacting nodes and one that determines the direction
of interaction as a function of the degrees of the two nodes and a parameter
$\alpha$ which sets the likelihood of the higher degree node giving its state.
Traditional voter model behavior can be recovered within the model. We find
that on a complete bipartite network, the traditional voter model is the
fastest process. On a random network with power law degree distribution, we
observe two regimes. For modest values of $\alpha$, exit time is dominated by
diffusive drift of the system state, but as the high nodes become more
influential, the exit time becomes becomes dominated by frustration effects.
For certain selection processes, a short intermediate regime occurs where exit
occurs after exponential mixing.


title: The quest for rings on bipolar scales

abstract:
  We consider the interval $]{-1},1[$ and intend to endow it with an algebraic
structure like a ring. The motivation lies in decision making, where scales
that are symmetric w.r.t. 0 are needed in order to represent a kind of symmetry
in the behaviour of the decision maker. A former proposal due to Grabisch was
based on maximum and minimum. In this paper, we propose to build our structure
on t-conorms and t-norms, and we relate this construction to uninorms. We show
that the only way to build a group is to use strict t-norms, and that there is
no way to build a ring. Lastly, we show that the main result of this paper is
connected to the theory of ordered Abelian groups.


title: Anomalous diffusion of a tethered membrane: A Monte Carlo investigation

abstract:
  Using a continuum bead-spring Monte Carlo model, we study the anomalous
diffusion dynamics of a self-avoiding tethered membrane by means of extensive
computer simulations. We focus on the subdiffusive stochastic motion of the
membrane's central node in the regime of flat membranes at temperatures above
the membrane folding transition. While at times, larger than the characteristic
membrane relaxation time $\tau_R$, the mean-square displacement of the center
of mass of the sheet, $<R_c^2>$, as well as that of its central node,
$<R_n^2>$, show the normal Rouse diffusive behavior with a diffusion
coefficient $D_N$ scaling as $D_N \propto N^{-1}$ with respect to the number of
segments $N$ in the membrane, for short times $t\le \tau_R$ we observe a {\em
multiscale dynamics} of the central node, $<R_n^2> \propto t^\alpha$, where the
anomalous diffusion exponent $\alpha$ changes from $\alpha \approx 0.86$ to
$\alpha \approx 0.27$, and then to $\alpha \approx 0.5$, before diffusion turns
eventually to normal. By means of simple scaling arguments we show that our
main result, $\alpha \approx 0.27$, can be related to particular mechanisms of
membrane dynamics which involve different groups of segments in the membrane
sheet. A comparative study involving also linear polymers demonstrates that the
diffusion coefficient of self-avoiding tethered membranes, containing $N$
segments, is three times smaller than that of linear polymer chains with the
same number of segments.


title:
Spin Chirality in a Molecular Dysprosium Triangle: the Archetype of the
  Non-Collinear Ising Model

abstract:
  Single crystal magnetic studies combined with a theoretical analysis show
that cancellation of the magnetic moments in the trinuclear Dy3+ cluster
[Dy3(OH)2L3Cl(H2O)5]Cl3, resulting in a non-magnetic ground doublet, originates
from the non-collinearity of the single ion easy axes of magnetization of the
Dy3+ ions that lie in the plane of the triangle at 120 (deg.) one from each
other. This gives rise to a peculiar chiral nature of the ground non-magnetic
doublet and to slow relaxation of the magnetization with abrupt accelerations
at the crossings of the discrete energy levels.


title:
Nanoscale periodicity in stripe-forming systems at high temperature:
  Au/W(110)

abstract:
  We observe using low-energy electron microscopy the self-assembly of
monolayer-thick stripes of Au on W(110) near the transition temperature between
stripes and the non-patterned (homogeneous) phase. We demonstrate that the
amplitude of this Au stripe phase decreases with increasing temperature and
vanishes at the order-disorder transition (ODT). The wavelength varies much
more slowly with temperature and coverage than theories of stress-domain
patterns with sharp phase boundaries would predict, and maintains a finite
value of about 100 nm at the ODT. We argue that such nanometer-scale stripes
should often appear near the ODT.


title: A note on Chern character, loop spaces and derived algebraic geometry

abstract:
  In this note we present a work in progress whose main purpose is to establish
a categorified version of sheaf theory. We present a notion of derived
categorical sheaves, which is a categorified version of the notion of complexes
of sheaves of modules on schemes, as well as its quasi-coherent and perfect
versions. We also explain how ideas from derived algebraic geometry and higher
category theory can be used in order to construct a Chern character for these
categorical sheaves, which is a categorified version of the Chern character for
perfect complexes with values in cyclic homology. Our construction uses in an
essential way the derived loop space of a scheme X, which is a derived scheme
whose theory of functions is closely related to cyclic homology of X. This work
can be seen as an attempt to define algebraic analogs of elliptic objects and
characteristic classes for them. The present text is an overview of a work in
progress and details will appear elsewhere.


title: Geometric optics and boundary layers for Nonlinear Schrodinger equations

abstract:
  We justify supercritical geometric optics in small time for the defocusing
semiclassical Nonlinear Schrodinger Equation for a large class of
non-necessarily homogeneous nonlinearities. The case of a half-space with
Neumann boundary condition is also studied.


title:
Radial Velocity Variable sdO/Bs from SPY - Preliminary Orbits of Three
  New Short Period Binaries

abstract:
  We present new results from follow-up time-resolved spectroscopy of radial
velocity variable hot subdwarfs from the SPY project. Medium resolution spectra
were taken at the ESO NTT. Preliminary orbital solutions are presented for
three single-lined sdO/B binaries. The orbital periods of all binaries are
short and the companions are most likely white dwarfs or late main-sequence
stars. Follow-up time-resolved spectroscopy is necessary to measure the orbital
parameters with higher accuracy. Light curves should be taken in order to
search for reflection effects and or eclipses.


title:
Hydrodynamics of Bose and Fermi superfluids at zero temperature: the
  superfluid nonlinear Schrodinger equation

abstract:
  We discuss the zero-temperature hydrodynamics equations of bosonic and
fermionic superfluids and their connection with generalized Gross-Pitaevskii
and Ginzburg-Landau equations through a single superfluid nonlinear Schrodinger
equation.


title:
Transition to Zero Cosmological Constant and Phantom Dark Energy as
  Solutions Involving Change of Orientation of Space-Time Manifold

abstract:
  Solutions with degenerate metric ($det(g_{\mu\nu})=0$ or $g_{\mu\nu}=0$) in
the first order formalism (FOF) are physically acceptable: they may describe
topology changes (Horowitz) and reduction of "metrical dimension" (Tseytlin) of
space-time. The latter implies disappearance of the volume element
$\sqrt{-g}d^4x$ of 4-D space-time. We pay attention that besides $\sqrt{-g}$,
the 4-D space-time differentiable manifold possesses also a "manifold volume
measure" (MVM)described by a 4-form which is sign indefinite and generically
independent of the metric. The FOF proceeds with originally independent
connection and metric structures of the space-time manifold. We bring up the
question whether the FOF should be supplemented with degrees of freedom of MVM.
Adding such manifold degrees of freedom to the action principle in the FOF we
realize very interesting dynamics. Such Two Measures Theory enables radically
new approaches to resolution of the cosmological constant problem. We show that
fine tuning free solutions describing a transition to $\Lambda =0$ state
involve oscillations of $g_{\mu\nu}$ and MVM around zero. The latter can be
treated as a dynamics involving changes of orientation of the space-time
manifold. As we have shown earlier, in realistic scale invariant models (SIM),
solutions formulated in the Einstein frame satisfy all existing tests of
General Relativity (GR). Here we reveal surprisingly that in SIM, all ground
state solutions with $\Lambda\neq 0$ appear to be degenerate either in $g_{00}$
or in MVM. Sign indefiniteness of MVM in a natural way yields a dynamical
realization of a phantom cosmology ($w<-1$). For all solutions, the metric
tensor rewritten in the Einstein frame has regularity properties exactly as in
GR. A possibility of a strong gravity effect in LHC experiments is discussed.


title: Notes on link homology

abstract:
  This article consists of six lectures on the categorification of the Burau
representation and on link homology groups which categorify the Jones and the
HOMFLY-PT polynomial. The notes are based on the lecture course at the PCMI
2006 summer school in Park City, Utah.


title: Maximal integral point sets over $\mathbb{Z}^2$

abstract:
  Geometrical objects with integral side lengths have fascinated mathematicians
through the ages. We call a set $P=\{p_1,...,p_n\}\subset\mathbb{Z}^2$ a
maximal integral point set over $\mathbb{Z}^2$ if all pairwise distances are
integral and every additional point $p_{n+1}$ destroys this property. Here we
consider such sets for a given cardinality and with minimum possible diameter.
We determine some exact values via exhaustive search and give several
constructions for arbitrary cardinalities. Since we cannot guarantee the
maximality in these cases we describe an algorithm to prove or disprove the
maximality of a given integral point set. We additionally consider restrictions
as no three points on a line and no four points on a circle.


title: Data Reduction in Intrusion Alert Correlation

abstract:
  Network intrusion detection sensors are usually built around low level models
of network traffic. This means that their output is of a similarly low level
and as a consequence, is difficult to analyze. Intrusion alert correlation is
the task of automating some of this analysis by grouping related alerts
together. Attack graphs provide an intuitive model for such analysis.
Unfortunately alert flooding attacks can still cause a loss of service on
sensors, and when performing attack graph correlation, there can be a large
number of extraneous alerts included in the output graph. This obscures the
fine structure of genuine attacks and makes them more difficult for human
operators to discern. This paper explores modified correlation algorithms which
attempt to minimize the impact of this attack.


title: Binary sdB Stars with Massive Compact Companions

abstract:
  The masses of compact objects like white dwarfs, neutron stars and black
holes are fundamental to astrophysics, but very difficult to measure. We
present the results of an analysis of subluminous B (sdB) stars in close binary
systems with unseen compact companions to derive their masses and clarify their
nature. Radial velocity curves were obtained from time resolved spectroscopy.
The atmospheric parameters were determined in a quantitative spectral analysis.
Based on high resolution spectra we were able to measure the projected
rotational velocity of the stars with high accuracy. In the distribution of
projected rotational velocities signs of tidal locking with the companions are
visible. By detecting ellipsoidal variations in the lightcurve of an sdB binary
we were able to show that subdwarf binaries with orbital periods up to 0.6 d
are most likely synchronized. In this case, the inclination angles and
companion masses of the binaries can be tightly constrained. Five invisible
companions have masses that are compatible with that of normal white dwarfs or
late type main sequence stars. However, four sdBs have compact companions
massive enough to be heavy white dwarfs (>1 Msun), neutron stars or even black
holes. Such a high fraction of massive compact companions is not expected from
current models of binary evolution.


title: Hidden Order in Crackling Noise during Peeling of an Adhesive Tape

abstract:
  We address the long standing problem of recovering dynamical information from
noisy acoustic emission signals arising from peeling of an adhesive tape
subject to constant traction velocity. Using phase space reconstruction
procedure we demonstrate the deterministic chaotic dynamics by establishing the
existence of correlation dimension as also a positive Lyapunov exponent in a
mid range of traction velocities. The results are explained on the basis of the
model that also emphasizes the deterministic origin of acoustic emission by
clarifying its connection to sticks-slip dynamics.

categories: cond-mat.stat-mech astro-ph cond-mat.mtrl-sci nlin.CD


title: Fluorine Abundances in the Milky Way Bulge

abstract:
  Fluorine (19F) abundances are derived in a sample of 6 bulge red giants in
Baade's Window. These giants span a factor of 10 in metallicity and this is the
first study to define the behavior of 19F with metallicity in the bulge. The
bulge results show an increase in F/O with increasing oxygen. This trend
overlaps what is found in the disk at comparable metallicities, with the most
oxygen-rich bulge target extending the disk trend. The increase in F/O in the
disk arises from 19F synthesis in both asymptotic giant branch (AGB) stars and
metal-rich Wolf-Rayet (WR) stars through stellar winds. The lack of an
s-process enhancement in the most fluorine-rich bulge giant in this study,
suggests that WR stars represented a larger contribution than AGB stars to 19F
production in the bulge when compared to the disk. If this result for fluorine
is combined with the previously published overall decline in the O/Mg abundance
ratios in metal-rich bulge stars, it suggests that WR winds played a role in
shaping chemical evolution in the bulge. One star in this study exhibits a very
low value of F/O while having a large O-abundance; this chemical mixture can be
understood if this star formed from gas that was enriched by metal-poor
core-collapse supernovae and may indicate that chemical evolution in the bulge
was inhomogeneous.


title: Maximal integral point sets in affine planes over finite fields

abstract:
  Motivated by integral point sets in the Euclidean plane, we consider integral
point sets in affine planes over finite fields. An integral point set is a set
of points in the affine plane $\mathbb{F}_q^2$ over a finite field
$\mathbb{F}_q$, where the formally defined squared Euclidean distance of every
pair of points is a square in $\mathbb{F}_q$. It turns out that integral point
sets over $\mathbb{F}_q$ can also be characterized as affine point sets
determining certain prescribed directions, which gives a relation to the work
of Blokhuis. Furthermore, in one important sub-case integral point sets can be
restated as cliques in Paley graphs of square order. In this article we give
new results on the automorphisms of integral point sets and classify maximal
integral point sets over $\mathbb{F}_q$ for $q\le 47$. Furthermore, we give two
series of maximal integral point sets and prove their maximality.


title:
Paired composite fermion phase of quantum Hall bilayers at \nu = 1/2 +
  1/2

abstract:
  We provide numerical evidence for composite fermion pairing in quantum Hall
bilayer systems at filling $\nu=1/2 + 1/2$ for intermediate spacing between the
layers. We identify the phase as $p_x + i p_y$ pairing, and construct high
accuracy trial wavefunctions to describe the groundstate on the sphere. For
large distances between the layers, and for finite systems, a competing "Hund's
rule" state, or composite fermion liquid, prevails for certain system sizes. We
argue that for larger systems, the pairing phase will persist to larger layer
spacing.


title: Metal Abundances of Subdwarf B Stars from SPY - a Pattern Emerges

abstract:
  The formation of sdBs is still puzzling, as is the chemical composition of
their atmospheres. While helium and other light elements are depleted relative
to solar values, heavy elements are highly enriched. Diffusion processes in the
hot, radiative atmosphere of these stars are the most likely explanation.
Although several attempts were made, it was not yet possible to model all the
observed features of sdB atmospheres. A setback of most prior studies was the
small sample size. We present a detailed abundance analysis of 68 sdBs. From
high resolution spectra obtained with the VLT/UVES instrument in the course of
the ESO Supernova Progenitor Survey (SPY) we measured elemental abundances of
up to 24 different ions per star. A general trend of enrichment was found with
increasing temperature for most of the heavier elements. The lighter elements
like carbon, oxygen and nitrogen are depleted irrespective of the temperature.
Although there is considerable scatter from one star to another, the general
abundance patterns in most sdBs are similar. An interplay between gravitational
settling, radiative levitation and weak winds is most likely responsible. About
6 % of the analysed stars show an enrichment in carbon and helium which cannot
be explained in the framework of diffusion alone. Nuclear processed material
must have been transported to the surface. The late hot-flasher scenario may
provide a possible explanation for this effect.


title: EtabFDC: an $\eta_b$ event generator in hadroproduction at LHC

abstract:
  The EtabFDC is a matrix-element event generator package for $\eta_b$
hadroproduction at LHC. It generates $pp\to\eta_b X$ events for all possible
parton-level $2\to2$ leading-order processes with three commonly used $\eta_b$
decay channels being implemented. The \pythia interface is used for
parton-shower and hadronization to obtain the hadronic events. The FORTRAN
codes of this package are generated by FDC (Feynman Diagram Calculation) system
automatically.


title: Integral point sets over finite fields

abstract:
  We consider point sets in the affine plane $\mathbb{F}_q^2$ where each
Euclidean distance of two points is an element of $\mathbb{F}_q$. These sets
are called integral point sets and were originally defined in $m$-dimensional
Euclidean spaces $\mathbb{E}^m$. We determine their maximal cardinality
$\mathcal{I}(\mathbb{F}_q,2)$. For arbitrary commutative rings $\mathcal{R}$
instead of $\mathbb{F}_q$ or for further restrictions as no three points on a
line or no four points on a circle we give partial results. Additionally we
study the geometric structure of the examples with maximum cardinality.


title:
Toroidal versus poloidal magnetic fields in Sun-like stars: a rotation
  threshold

abstract:
  From a set of stellar spectropolarimetric observations, we report the
detection of surface magnetic fields in a sample of four solar-type stars,
namely HD 73350, HD 76151, HD 146233 (18 Sco) and HD 190771. Assuming that the
observed variability of polarimetric signal is controlled by stellar rotation,
we establish the rotation periods of our targets, with values ranging from 8.8
d (for HD 190771) to 22.7 d (for HD 146233). Apart from rotation, fundamental
parameters of the selected objects are very close to the Sun's, making this
sample a practical basis to investigate the specific impact of rotation on
magnetic properties of Sun-like stars.
  We reconstruct the large-scale magnetic geometry of the targets as a
low-order (l<10) spherical harmonics expansion of the surface magnetic field.
  From the set of magnetic maps, we draw two main conclusions. (a) The magnetic
energy of the large-scale field increases with rotation rate. The increase of
chromospheric emission with the mean magnetic field is flatter than observed in
the Sun. Since the chromospheric flux is also sensitive to magnetic elements
smaller than those contributing to the polarimetric signal, this observation
suggests that a larger fraction of the surface magnetic energy is stored in
large scales as rotation increases. (b) Whereas the magnetic field is mostly
poloidal for low rotation rates, more rapid rotators host a large-scale
toroidal component in their surface field. From our observations, we infer that
a rotation period lower than ~12 days is necessary for the toroidal magnetic
energy to dominate over the poloidal component.


title: Pointwise Trichotomy for Skew-Evolution Semiflows on Banach Spaces

abstract:
  The paper introduces the notion of skew-evolution semiflows and presents the
concept of pointwise trichotomy in the case of skew-evolution semiflows on a
Banach space. The connection with the classic notion of trichotomy presented by
us in a previous paper in 2006 for evolution operators, is also emphasized, as
well as some characterizations. The approach of the theory is from uniform
point of view. The study can also be extended to systems with control whose
state evolution can be described by skew-evolution semiflows.


title: Khovanov homology and star-like isotopies

abstract:
  A star-like isotopy for oriented links in 3-space is an isotopy which uses
only Reidemeister II moves with opposite orientations and Reidemeister III
moves with alternating orientations when checking the strands clockwise (or
anticlockwise). We define a link polynomial derived from the Jones polynomial
which is, in general, only invariant under star-like isotopies and we
categorify it.