pinecone/core-2020-05-10-deduplication huggingface dataset:
Using satellite radar backscatter to predict above-ground woody biomass: A consistent relationship across four different African landscapes

Reproduced with permission of the publisher. © 2009 American Geophysical UnionRegional-scale above-ground biomass (AGB) estimates of tropical savannas and woodlands are highly uncertain, despite their global importance for ecosystems services and as carbon stores. In response, we collated field inventory data from 253 plots at four study sites in Cameroon, Uganda and Mozambique, and examined the relationships between field-measured AGB and cross-polarized radar backscatter values derived from ALOS PALSAR, an L-band satellite sensor. The relationships were highly significant, similar among sites, and displayed high prediction accuracies up to 150 Mg ha−1 (±∼20%). AGB predictions for any given site obtained using equations derived from data from only the other three sites generated only small increases in error. The results suggest that a widely applicable general relationship exists between AGB and L-band backscatter for lower-biomass tropical woody vegetation. This relationship allows regional-scale AGB estimation, required for example by planned REDD (Reducing Emissions from Deforestation and Degradation) schemes
Embedding A4 into left-right flavor symmetry: Tribimaximal neutrino
  mixing and fermion hierarchy

We address two fundamental aspects of flavor physics: the mass hierarchy and
the large lepton mixing angles. On one side, left-right flavor symmetry
realizes the democratic mass matrix patterns and explains why one family is
much heavier than the others. On the other side, discrete flavor symmetry such
as A4 leads to the observed tribimaximal mixing for the leptons. We show that,
by explicitly breaking the left-right flavor symmetry into the diagonal A4, it
is possible to explain both the observed charged fermion mass hierarchies and
quark and lepton mixing angles. In particular we predict a heavy 3rd family,
the tribimaximal mixing for the leptons, and we suggest a possible origin of
the Cabibbo and other mixing angles for the quarks.Comment: 9 pages, uses revtex4 and axodraw.st
BDNF in the dentate gyrus is required for consolidation of "pattern-separated" memories

Contains fulltext :
                  125283.pdf (publisher's version ) (Open Access)Successful memory involves not only remembering information over time, but also keeping memories distinct and less confusable. The computational process for making representations for similar input patterns more distinct from each other has been referred to as "pattern separation." In this work, we developed a set of behavioral conditions that allowed us to manipulate the load for pattern separation at different stages of memory. Thus, we provide experimental evidence that a brain-derived neurotrophic factor (BDNF)-dependent pattern separation process occurs during the encoding/storage/consolidation, but not the retrieval stage of memory processing. We also found that a spontaneous increase in BDNF in the dentate gyrus of the hippocampus is associated with exposure to landmarks delineating similar, but not dissimilar, spatial locations, suggesting that BDNF is expressed on an "as-needed" basis for pattern separation
An axiomatic formulation of the Montevideo interpretation of quantum
  mechanics

We make a first attempt to axiomatically formulate the Montevideo
interpretation of quantum mechanics. In this interpretation environmental
decoherence is supplemented with loss of coherence due to the use of realistic
clocks to measure time to solve the measurement problem. The resulting
formulation is framed entirely in terms of quantum objects without having to
invoke the existence of measurable classical quantities like the time in
ordinary quantum mechanics. The formulation eliminates any privileged role to
the measurement process giving an objective definition of when an event occurs
in a system.Comment: 21 pages, RevTex, final version to appear in Studies in the History
  and Philosophy of Modern Physic
The Cool Accretion Disk in ESO 243-49 HLX-1: Further Evidence of an
  Intermediate Mass Black Hole

With an inferred bolometric luminosity exceeding 10^42 erg/s, HLX-1 in ESO
243-49 is the most luminous of ultraluminous X-ray sources and provides one of
the strongest cases for the existence of intermediate mass black holes. We
obtain good fits to disk-dominated observations of the source with BHSPEC, a
fully relativistic black hole accretion disk spectral model. Due to
degeneracies in the model arising from the lack of independent constraints on
inclination and black hole spin, there is a factor of 100 uncertainty in the
best-fit black hole mass M. Nevertheless, spectral fitting of XMM-Newton
observations provides robust lower and upper limits with 3000 Msun < M < 3 x
10^5 Msun, at 90% confidence, placing HLX-1 firmly in the intermediate-mass
regime. The lower bound on M is entirely determined by matching the shape and
peak energy of the thermal component in the spectrum. This bound is consistent
with (but independent of) arguments based solely on the Eddington limit. Joint
spectral modelling of the XMM-Newton data with more luminous Swift and Chandra
observations increases the lower bound to 6000 Msun, but this tighter
constraint is not independent of the Eddington limit. The upper bound on M is
sensitive to the maximum allowed inclination i, and is reduced to M < 10^5 Msun
if we limit i < 75 deg.Comment: 10 pages, 7 figures, accepted for publication in Ap
Measurement of zero degree single photon energy spectra for sqrt(s) =
  7TeV proton-proton collisions at LHC

In early 2010, the Large Hadron Collider forward (LHCf) experiment measured
very forward neutral particle spectra in LHC proton-proton collisions. From a
limited data set taken under the best beam conditions (low beam-gas background
and low occurance of pile-up events), the single photon spectra at sqrt(s)=7TeV
and pseudo-rapidity (eta) ranges from 8.81 to 8.99 and from 10.94 to infinity
were obtained for the first time and are reported in this paper. The spectra
from two independent LHCf detectors are consistent with one another and serve
as a cross check of the data. The photon spectra are also compared with the
predictions of several hadron interaction models that are used extensively for
modeling ultra high energy cosmic ray showers. Despite conservative estimates
for the systematic errors, none of the models agree perfectly with the
measurements. A notable difference is found between the data and the DPMJET
3.04 and PYTHIA 8.145 hadron interaction models above 2TeV where the models
predict higher photon yield than the data. The QGSJET II-03 model predicts
overall lower photon yield than the data, especially above 2TeV in the rapidity
range 8.81<eta<8.99
Rotational-vibrational coupling in the BPS Skyrme model of baryons

We calculate the rotational-vibrational spectrum in the BPS Skyrme model for
the hedgehog skyrmion with baryon number one. The resulting excitation energies
for the nucleon and delta Roper resonances are slightly above their
experimental values. Together with the fact that in the standard Skyrme model
these excitation energies are significantly lower than the experimental ones,
this provides strong evidence for the conjecture that the inclusion of the BPS
Skyrme model is necessary for a successful quantitative description of physical
properties of baryons and nuclei.Comment: Latex, 9 pages. v2: some references adde
On the ERG approach in $3 - d$ Well Developed Turbulence

We apply the method of the Renormalization Group (GR), following the Polchinski point of view, to a model of well developed and isotropic fluid turbulence. The Galilei-invariance is preserved and a universal behavior, related to the change of the stochastic stirring force, is evident by the numerical results in the inertial region, where a scale-invariant behavior also appear. The expected power law of the energy spectrum ($q^{-{5\over 3}}$) is obtained and the Kolmogorov constant $C_K$ agrees with experimental data
(Non)thermal aspects of charmonium production and a new look at $J/\psi$ suppression

To investigate a recent proposal that J/$\psi$ production in ultra-relativistic nuclear collisions is of thermal origin we have reanalyzed the data from the NA38/50 collaboration within a thermal model including charm. Comparison of the calculated with measured yields demonstrates the non-thermal origin of hidden charm production at SPS energy. However, the ratio $\psi^{'}$/(J/$\psi)$ exhibits, in central nucleus-nucleus collisions, thermal features which lead us to a new interpretation of open charm and charmonium production at SPS energy. Implications for RHIC and LHC energy measurements will be discussed
Nature of the deconfining phase transition in the 2+1-dimensional SU(N)
  Georgi-Glashow model

The nature of the deconfining phase transition in the 2+1-dimensional SU(N)
Georgi-Glashow model is investigated. Within the dimensional-reduction
hypothesis, the properties of the transition are described by a two-dimensional
vectorial Coulomb gas models of electric and magnetic charges. The resulting
critical properties are governed by a generalized SU(N) sine-Gordon model with
self-dual symmetry. We show that this model displays a massless flow to an
infrared fixed point which corresponds to the Z$\_N$ parafermions conformal
field theory. This result, in turn, supports the conjecture of Kogan, Tekin,
and Kovner that the deconfining transition in the 2+1-dimensional SU(N)
Georgi-Glashow model belongs to the Z$\_N$ universality class.Comment: 12 page
Worldsheet Instantons, Torsion Curves, and Non-Perturbative
  Superpotentials

As a first step towards computing instanton-generated superpotentials in
heterotic standard model vacua, we determine the Gromov-Witten invariants for a
Calabi-Yau threefold with fundamental group pi_1(X)=Z_3 x Z_3. We find that the
curves fall into homology classes in H_2(X,Z)=Z^3+(Z_3+Z_3). The unexpected
appearance of the finite torsion subgroup in the homology group complicates our
analysis. However, we succeed in computing the complete genus-0 prepotential.
Expanding it as a power series, the number of instantons in any integral
homology class can be read off. This is the first explicit calculation of the
Gromov-Witten invariants of homology classes with torsion. We find that some
curve classes contain only a single instanton. This ensures that the
contribution to the superpotential from each such instanton cannot cancel.Comment: 14 pages, LaTe
A Weil-Barsotti formula for Drinfeld modules

We study the group of extensions in the category of Drinfeld modules and
Anderson's t-modules, and we show in certain cases that this group can itself
be given the structure of a t-module. Our main result is a Drinfeld module
analogue of the Weil-Barsotti formula for abelian varieties. Extensions of
general t-modules are also considered, in particular extensions of tensor
powers of the Carlitz module. We motivate these results from various directions
and compare to the situation of elliptic curves.Comment: 20 pages, latex file. To appear in Journal of Number Theor
Limiting modular symbols and their fractal geometry

In this paper we use fractal geometry to investigate boundary aspects of the
first homology group for finite coverings of the modular surface. We obtain a
complete description of algebraically invisible parts of this homology group.
More precisely, we first show that for any modular subgroup the geodesic
forward dynamic on the associated surface admits a canonical symbolic
representation by a finitely irreducible shift space. We then use this
representation to derive an `almost complete' multifractal description of the
higher--dimensional level sets arising from Manin--Marcolli's limiting modular
symbols.Comment: 20 pages, 1 figur
Dynamic Fitness Landscapes in Molecular Evolution

We study self-replicating molecules under externally varying conditions.
Changing conditions such as temperature variations and/or alterations in the
environment's resource composition lead to both non-constant replication and
decay rates of the molecules. In general, therefore, molecular evolution takes
place in a dynamic rather than a static fitness landscape. We incorporate
dynamic replication and decay rates into the standard quasispecies theory of
molecular evolution, and show that for periodic time-dependencies, a system of
evolving molecules enters a limit cycle for $t\to\infty$. For fast periodic
changes, we show that molecules adapt to the time-averaged fitness landscape,
whereas for slow changes they track the variations in the landscape arbitrarily
closely. We derive a general approximation method that allows us to calculate
the attractor of time-periodic landscapes, and demonstrate using several
examples that the results of the approximation and the limiting cases of very
slow and very fast changes are in perfect agreement. We also discuss landscapes
with arbitrary time dependencies, and show that very fast changes again lead to
a system that adapts to the time-averaged landscape. Finally, we analyze the
dynamics of a finite population of molecules in a dynamic landscape, and
discuss its relation to the infinite population limit.Comment: LaTeX, 60 pages, 14 eps figures, expanded introduction, minor
  corrections, submitted to Phys. Re
Degree-Scale Cosmic Microwave Background Polarization Measurements From Three Years of BICEP1 Data

BICEP1 is a millimeter-wavelength telescope designed specifically to measure the inflationary B-mode polarization of the cosmic microwave background at degree angular scales.  We present results from an analysis of the data acquired during three seasons of observations at the South Pole (2006-2008).  This work extends the two-year result published in Chiang et al., with additional data from the third season and relaxed detector-selection criteria.  This analysis also introduces a more comprehensive estimation of band power window functions, improved likelihood estimation methods, and a new technique for deprojecting monopole temperature-to-polarization leakage that reduces this class of systematic uncertainty to a negligible level.  We present maps of temperature, E- and B-mode polarization, and their associated angular power spectra.  The improvement in the map noise level and polarization spectra error bars are consistent with the 52% increase in integration time relative to Chiang et al.  We confirm both self-consistency of the polarization data and consistency with the two-year results. We measure the angular power spectra at \(21 \leq l \leq 335\) and find that the EE spectrum is consistent with Lambda cold dark matter cosmology, with the first acoustic peak of the EE spectrum now detected at \(15\sigma\).  The BB spectrum remains consistent with zero.  From B-modes only, we constrain the tensor-to-scalar ratio to \(r = 0.03^{+0.27}_{-0.23}\), or \(r < 0.70\) at 95% confidence level.Astronom
Static and dynamic modifications to photon absorption:The effects of surrounding chromophores

This Letter investigates the influence, on the molecular absorption of light, of surrounding chromophores. Two novel rate contributions are identified - one vanishing for a medium with no static dipole moment. The other, dynamic term is used to model a system of primary absorbers and secondary chromophores distributed in a host medium. Further modification provides a basis for modelling a case where the medium is, itself, marginally absorptive, thus accounting for optical losses as the input propagates through the surrounding host. The results facilitate tailoring of secondary chromophore and host effects in the pursuit of materials with specific absorption features
Modeling Requirements for Value Configuration Design

Breadth and depth complexity are key challenges in achieving business process fusion as the enabler for value configuration design. The PARM framework is proposed as the requirement to address breadth and depth complexity through the independent but integrated operation of the process, activity, resource and management viewpoints. The operational scenarios for each viewpoint result in varying process modeling extension requirements. Existing process modeling constructs have varying support for these requirements. The PARM framework solution is an extension and integration of existing modeling constructs rather than a solution in its own right. Using the MDA approach of abstracting a platform independent model from a platform specific implementation, it is the goal in future papers to define process modeling extensions to support the PARM framework and map these into existing implementation architectures
Fossil group origins V. The dependence of the luminosity function on the
  magnitude gap

In nature we observe galaxy aggregations that span a wide range of magnitude
gaps between the two first-ranked galaxies of a system ($\Delta m_{12}$). There
are systems with gaps close to zero (e.g., the Coma cluster), and at the other
extreme of the distribution, the largest gaps are found among the so-called
fossil systems. Fossil and non-fossil systems could have different galaxy
populations that should be reflected in their luminosity functions. In this
work we study, for the first time, the dependence of the luminosity function
parameters on $\Delta m_{12}$ using data obtained by the fossil group origins
(FOGO) project. We constructed a hybrid luminosity function for 102 groups and
clusters at $z \le 0.25$. We stacked all the individual luminosity functions,
dividing them into bins of $\Delta m_{12}$, and studied their best-fit
Schechter parameters. We additionally computed a relative luminosity function,
expressed as a function of the central galaxy luminosity, which boosts our
capacity to detect differences, especially at the bright end. We find trends as
a function of $\Delta m_{12}$ at both the bright and faint ends of the
luminosity function. In particular, at the bright end, the larger the magnitude
gap, the fainter the characteristic magnitude $M^\ast$. We also find
differences at the faint end. In this region, the larger the gap, the flatter
the faint-end slope $\alpha$. The differences found at the bright end support a
dissipationless, dynamical friction-driven merging model for the growth of the
central galaxy in group- and cluster-sized halos. The differences in the faint
end cannot be explained by this mechanism. Other processes, such as enhanced
tidal disruption due to early infall and/or prevalence of eccentric orbits, may
play a role. However, a larger sample of systems with $\Delta m_{12} > 1.5$ is
needed to establish the differences at the faint end.Comment: 11 pages, 10 figures, accepted for publication in A&
Sharp $L^p$ estimates for discrete second order {R}iesz transforms

We show that multipliers of second order Riesz transforms on products of
discrete abelian groups enjoy the $L^{p} $ estimate $p^{\ast} -1$, where
$p^{\ast} = \max \{ p,q \}$ and $p$ and $q$ are conjugate exponents. This
estimate is sharp if one considers all multipliers of the form $\sum_i
\sigma_{i} R_{i} R^{\ast}_{i}$ with $| \sigma_{i} | \leqslant 1$ and infinite
groups. In the real valued case, we obtain better sharp estimates for some
specific multipliers, such as $\sum_{i} \sigma_{i} R_{i} R^{\ast}_{i}$ with $0
\leqslant \sigma_{i} \leqslant 1$. These are the first known precise $L^{p} $
estimates for discrete Calder\'on-Zygmund operators.Comment: 22 page
CO ro-vibrational lines in HD 100546 A search for disc asymmetries and the role of fluorescence

I.K., W.F.T., and P.W. acknowledge funding from the EU FP7-2011 under Grant Agreement no. 284405 (PERG06-GA-2009-256513). G.v.d.P. acknowledges support from the Millennium Science Initiative (Chilean Ministry of Economy), through grant “Nucleus P10-022-F”.Aims. We have studied the emission of CO ro-vibrational lines in the disc around the Herbig Be star HD 100546 to determine physical properties, disc asymmetries, the CO excitation mechanism, and the spatial extent of the emission, with the final goal of using the CO ro-vibrational lines as a diagnostic to understand inner disc structure in the context of planet formation. Methods. High-spectral-resolution infrared spectra of CO ro-vibrational emission at eight different position angles were taken with the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES) at the Very Large Telescope (VLT). From these spectra flux tables, line profiles for individual CO ro-vibrational transitions, co-added line profiles, and population diagrams were produced. We have investigated variations in the line profile shapes and line strengths as a function of slit position angle. We used the thermo-chemical disc modelling code ProDiMo based on the chemistry, radiation field, and temperature structure of a previously published model for HD 100546. We calculated line fluxes and profiles for the whole set of observed CO ro-vibrational transitions using a large CO model molecule that includes the lowest two electronic states, each with 7 vibrational levels and within them 60 rotational levels. Comparing observations and the model, we investigated the possibility of disc asymmetries, the excitation mechanism (UV fluorescence), the geometry, and physical conditions of the inner disc. Results. The observed CO ro-vibrational lines are largely emitted from the inner rim of the outer disc at 10-13 AU. The line shapes are similar for all v levels and line fluxes from all vibrational levels vary only within one order of magnitude. All line profile asymmetries and variations can be explained with a symmetric disc model to which a slit correction and pointing offset is applied. Because the angular size of the CO emitting region (10-13 AU) and the slit width are comparable the line profiles are very sensitive to the placing of the slit. The model reproduces the line shapes and the fluxes of the v = 1-0 lines as well as the spatial extent of the CO ro-vibrational emission. It does not reproduce the observed band ratios of 0.5-0.2 with higher vibrational bands. We find that lower gas volume densities at the surface of the inner rim of the outer disc can make the fluorescence pumping more efficient and reproduce the observed band ratios.Publisher PDFPeer reviewe
The effect of neuronal conditional knock-out of peroxisome proliferator-activated receptors in the MPTP mouse model of Parkinson's disease

This study was supported by Parkinson’s Disease Foundation (IRGP 09-11 (P.T.)), the Royal Society (2006/R1 (P.T.)), the Wellcome Trust (WT080782MF (P.T.)), the Biotechnology and Biological Sciences Research Council (P.T. and H.L.M.), the National Institutes of Health (DK057978) (R.M.E.), and by grants from the Leona M. and Harry B. Helmsley Charitable Trust (R.M.E.), the Glenn Foundation for Medical Research (R.M.E.), and the Ellison Medical Foundation (R.M.E.). R.M.E. is an investigator at the Howard Hughes Medical Institute and March of Dimes Chair in Molecular and Developmental Biology at the Salk Institute. The authors would like to thank Lynne J. Hocking, University of Aberdeen, for her assistance with the statistics. We are grateful to the staff of the Medical Research Facility for their help with the animal care and the microscopy core facility at the University of Aberdeen for the use of microscopy equipment.Peer reviewedPublisher PD