pinecone/core-2020-05-10-deduplication huggingface dataset:
Two-Loop Quark Self-Energy in a New Formalism: (I) Overlapping
  Divergences

A new integration technique for multi-loop Feynman integrals, called the
matrix method, is developed and then applied to the divergent part of the
overlapping two-loop quark self-energy function $\,i\Sigma\,$ in the light-
cone gauge. It is shown that the coefficient of the double-pole term is
strictly local, even off mass-shell, while the coefficient of the single-pole
term contains local as well as nonlocal parts. On mass-shell, the single-pole
part is local, of course. It is worth noting that the original overlapping
self-energy integral reduces eventually to 10 covariant and 38 noncovariant-
gauge integrals. We were able to verify explicitly that the divergent parts of
the 10 double covariant-gauge integrals agreed precisely with those currently
used to calculate radiative corrections in the Standard Model.
  Our new technique is amazingly powerful, being applicable to massive and
massless integrals alike, and capable of handling both covariant-gauge
integrals and the more difficult noncovariant-gauge integrals. Perhaps the most
important feature of the matrix method is the ability to execute the
$4\omega$-dimensional momentum integrations in a single operation, exactly and
in analytic form. The method works equally well for other axial-type gauges,
notably the temporal gauge ($n^2>0$) and the pure axial gauge ($n^2<0$).Comment: 42 pages, 1 typo fixed -- Equation 6.
Short-range correlations in (e,e$'$p) and (e,e$'$pp) reactions on
  complex nuclei

The influence of short-range correlations (SRC) on the triple-coincidence
(e,e$'$pp) reactions is studied. The non-relativistic model uses a mean-field
potential to account for the distortions that the escaping particles undergo.
Apart from the SRC, that are implemented through a Jastrow ansatz with a
realistic correlation function, we incorporate the contribution from pion
exchange and intermediate $\Delta _{33}$ currents. The (e,e$'$pp) cross
sections are predicted to exhibit a sizeable sensitivity to the SRC. The
contribution from the two-nucleon breakup channel to the semi-exclusive
$^{12}$C(e,e$'$p) cross section is calculated in the kinematics of a recent
NIKHEF-K experiment. In the semi-exclusive channel, a selective sensitivity in
terms of the missing energy and momentum to the SRC is found.Comment: 9 pages, Revtex, 3 figures included as an uuencoded and compressed
  Postscript fil
Coulomb distortion of pi+/pi- as a tool to determine the fireball radius
  in central high energy heavy ion collisions

We compute the Coulomb distortion produced by an expanding and highly charged
fireball on the spectra of low transverse momenta and mid rapidity pions
produced in central high energy heavy ion collisions. We compare to data on
Au+Au at 11.6A GeV from E866 at the BNL AGS and of Pb+Pb at 158A GeV from NA44
at the CERN SPS. We match the fireball expanison velocity with the average
transverse momentum of protons and find a best fit to the charged pion ratio
when the fireball radius is about 10 fm at freeze-out. This value is common to
both AGS and SPS data.Comment: 4 pages includes 2 figures, uses espcrc1 and epsfig. To appear in
  proceedings of QM99, Torino Italy, May 199
Dimensions of fractals related to languages defined by tagged strings in
  complete genomes

A representation of frequency of strings of length K in complete genomes of
many organisms in a square has led to seemingly self-similar patterns when K
increases. These patterns are caused by under-represented strings with a
certain "tag"-string and they define some fractals when K tends to infinite.
The Box and Hausdorff dimensions of the limit set are discussed. Although the
method proposed by Mauldin and Williams to calculate Box and Hausdorff
dimension is valid in our case, a different and simpler method is proposed in
this paper.Comment: 9 pages with two figure
Reduced cortical thickness with increased lifetime burden of PTSD in OEF/OIF Veterans and the impact of comorbid TBI☆

Posttraumatic stress disorder (PTSD) and mild traumatic brain injury (mTBI) in military personnel is increasing dramatically following the OEF/OIF conflicts and is associated with alterations to brain structure. The present study examined the relationship between PTSD and cortical thickness, and its possible modification by mTBI, in a 104-subject OEF/OIF veteran cohort ranging in age from 20 to 62 years. For each participant, two T1-weighted scans were averaged to create high-resolution images for calculation of regional cortical thickness. PTSD symptoms were assessed using the Clinician Administered PTSD Scale (CAPS) and scores were derived based on the previous month's symptoms (“current”) and a Cumulative Lifetime Burden of PTSD (CLB-P) reflecting the integral of CAPS scores across the lifetime. Mild TBI was diagnosed using the Boston Assessment of TBI-Lifetime (BAT-L). Results demonstrated a clear negative relationship between current PTSD severity and thickness in both postcentral gyri and middle temporal gyri. This relationship was stronger and more extensive when considering lifetime burden (CLB-P), demonstrating the importance of looking at trauma in the context of an individual's lifetime, rather than only at their current symptoms. Finally, interactions with current PTSD only and comorbid current PTSD and mTBI were found in several regions, implying an additive effect of lifetime PTSD and mTBI on cortical thickness
“God made the soil, but we made it fertile”: Gender, knowledge and practice in the formation and use of African Dark Earths in Liberia and Sierra Leone

This paper fills a significant knowledge gap by describing the West African farming practices and knowledge that lead to the formation of carbon-rich high-fertility African Dark Earths (AfDE) – human-made soils analogous to Amazonian terra preta - yet subject to continuing production and use. Gender relations and women’s roles are central to how these soils are produced and used. We develop a gendered political ecology perspective through social and ecological field studies in Liberia and Sierra Leone. We detail how AfDE formation and associated knowledge is gender-differentiated; the central roles of women’s deposition of charred organic materials from cooking, oil palm processing and potash production in producing AfDE, and the gendered dynamics of AfDE use and distribution in the landscape. Different species are cultivated in AfDE compared to non-anthropogenic soils, and AfDE are differentially valued by women and men for horticultural and tree crops. The spatial distribution of AfDE across the landscape reflects shifting household, marriage and settlement practices. Gender relations, subjectivities and interdependencies, and the ecology of soils and landscapes, mutually shape one another. National policy makers and NGOs (such as Care and Rainforest Alliance) planning or managing agricultural carbon projects in West Africa should attend to the knowledge and practices of Loma and Mende women and men who have made and cultivated carbon-rich anthropogenic soils in the region for generations.ESR
Planck 2015 results. XV. Gravitational lensing

We present the most significant measurement of the cosmic microwave
background (CMB) lensing potential to date (at a level of 40 sigma), using
temperature and polarization data from the Planck 2015 full-mission release.
Using a polarization-only estimator we detect lensing at a significance of 5
sigma. We cross-check the accuracy of our measurement using the wide frequency
coverage and complementarity of the temperature and polarization measurements.
Public products based on this measurement include an estimate of the lensing
potential over approximately 70% of the sky, an estimate of the lensing
potential power spectrum in bandpowers for the multipole range 40<L<400 and an
associated likelihood for cosmological parameter constraints. We find good
agreement between our measurement of the lensing potential power spectrum and
that found in the best-fitting LCDM model based on the Planck temperature and
polarization power spectra. Using the lensing likelihood alone we obtain a
percent-level measurement of the parameter combination $\sigma_8
\Omega_m^{0.25} = 0.591\pm 0.021$. We combine our determination of the lensing
potential with the E-mode polarization also measured by Planck to generate an
estimate of the lensing B-mode. We show that this lensing B-mode estimate is
correlated with the B-modes observed directly by Planck at the expected level
and with a statistical significance of 10 sigma, confirming Planck's
sensitivity to this known sky signal. We also correlate our lensing potential
estimate with the large-scale temperature anisotropies, detecting a
cross-correlation at the 3 sigma level, as expected due to dark energy in the
concordance LCDM model.Comment: 30 pages, 2 wide-format tables. Minor changes and typo fix to match
  published versio
Two-loop QCD Corrections to $B_c$ Meson Leptonic Decays

The two-loop QCD radiative corrections to the $B_c$ meson leptonic decay rate
are calculated in the framework of NRQCD factorization formalism. Two types of
master integrals appearing in the calculation are obtained analytically for the
first time. We get the short-distance coefficient of the leading matrix element
to order $\alpha_s^2$ by matching the full perturbative QCD calculation results
to the corresponding NRQCD ones. The result in this work helps the evaluation
of the $B_c$ leptonic decay constant, as well as the Cabibbo-Kobayashi-Maskawa
matrix element $|V_{cb}|$, to the full next-to-next-to-leading order degree of
accuracy.Comment: Typos are correcte
Fast Variability and mm/IR flares in GRMHD Models of Sgr A* from
  Strong-Field Gravitational Lensing

We explore the variability properties of long, high cadence GRMHD simulations
across the electromagnetic spectrum using an efficient, GPU-based radiative
transfer algorithm. We focus on both disk- and jet-dominated simulations with
parameters that successfully reproduce the time-averaged spectral properties of
Sgr A* and the size of its image at 1.3mm. We find that the disk-dominated
models produce short timescale variability with amplitudes and power spectra
that closely resemble those inferred observationally. In contrast,
jet-dominated models generate only slow variability, at lower flux levels.
Neither set of models show any X-ray flares, which most likely indicate that
additional physics, such as particle acceleration mechanisms, need to be
incorporated into the GRMHD simulations to account for them. The disk-dominated
models show strong, short-lived mm/IR flares, with short (<~ 1hr) time lags
between the mm and IR wavelengths, that arise from strong-field gravitational
lensing of magnetic flux tubes near the horizon. Such events provide a natural
explanation for the observed IR flares with no X-ray counterparts.Comment: 14 pages, 12 figures, submitted to Ap
Noncovalent functionalization of carbon nanotubes and graphene with
  tetraphenylporphyrins: Stability and optical properties from ab-initio
  calculations

The stability, electronic and optical properties of single-walled carbon
nanotubes (CNTs) and graphene noncovalently functionalized with free-base
tetraphenylporphyrin (TPP) molecules is addressed by density functional theory
calculations, including corrections to dispersive interactions. We study the
TPP physisorption on 42 CNT species, particularly those with chiral indices
($n$,$m$), where $5 \leq n \leq 12$ and $0\leq m\leq n$. Our results show a
quite strong $\pi$-$\pi$ interaction between TPP and the CNT surface, with
binding energies ranging from 1.1 to 1.8 eV, where higher energies can be
associated with increasing CNT diameters. We also find that the TPP optical
absorptions would not be affected by the CNT diameter or chirality. Results for
the TPP physisorption on graphene show a remarkable stability with binding
energy of 3.2 eV, inducing a small redshift on the $\pi$-stacked TPP absorption
bands. The strong graphene-TPP interaction also induces a charge transfer from
TPP to graphene, indicating a $n$-type doping mechanism without compromising
the graphene structure.Comment: Accepted for publication in Journal of Materials Scienc
Emergence of non-twisted magnetic fields in the Sun: Jets and
  atmospheric response

Aims. We study the emergence of a non-twisted flux tube from the solar
interior into the solar atmosphere. We investigate whether the length of the
buoyant part of the flux tube (i.e. {\lambda}) affects the emergence of the
field and the dynamics of the evolving magnetic flux system. Methods. We
perform three-dimensional (3D), time-dependent, resistive, compressible MHD
simulations using the Lare3D code. Results. We find that there are considerable
differences in the dynamics of the emergence of a magnetic flux tube when
{\lambda} is varied. In the solar interior, for larger values of {\lambda}, the
rising magnetic field emerges faster and expands more due to its lower magnetic
tension. As a result, its field strength decreases and its emergence above the
photosphere occurs later than in the smaller {\lambda} case. However, in both
cases, the emerging field at the photosphere becomes unstable in two places,
forming two magnetic bipoles that interact dynamically during the evolution of
the system. Most of the dynamic phenomena occur at the current layer, which is
formed at the interface between the interacting bipoles. We find the formation
and ejection of plasmoids, the onset of successive jets from the interface, and
the impulsive heating of the plasma in the solar atmosphere. We discuss the
triggering mechanism of the jets and the atmospheric response to the emergence
of magnetic flux in the two cases.Comment: 16 pages, 15 figure
Transiting planets from WASP-South, Euler, and TRAPPIST : WASP-68 b, WASP-73 b, and WASP-88 b, three hot Jupiters transiting evolved solar-type stars

Funding for WASP comes from consortium universities and from UK’s Science and Technology Facilities Council. TRAPPIST is a project funded by the Belgian Fund for Scientific Research (Fonds National de la Recherche Scientifique, F.R.S.-FNRS) under grant FRFC 2.5.594.09.F, with the participation of the Swiss National Science Fundation (SNF). L. Delrez acknowledges the support of the F.R.I.A. fund of the FNRS. M. Gillon and E. Jehin are FNRS Research Associates. A. H. M. J. Triaud received funding from a fellowship provided by the Swiss National Science Foundation under grant number PBGEP2-14559.Using the WASP transit survey, we report the discovery of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. The planet WASP-68 b has a mass of 0.95 ± 0.03 MJup, a radius of 1.24-0.06+0.10 RJup, and orbits a V = 10.7 G0-type star (1.24 ± 0.03 M⊙ 1.69-0.06+0.11 R⊙, Teff = 5911 ± 60 K) with a period of 5.084298 ± 0.000015 days. Its size is typical of hot Jupiters with similar masses. The planet WASP-73 bis significantly more massive (1.88-0.06+0.07 MJup) and slightly larger (1.16-0.08+0.12 RJup) than Jupiter. It orbits a V = 10.5 F9-type star (1.34-0.04+0.05 M⊙, 2.07-0.08+0.19 R⊙, Teff = 6036 ± 120 K) every 4.08722 ± 0.00022 days. Despite its high irradiation (~2.3 × 109 erg s-1 cm-2), WASP-73 b has a high mean density (1.20-0.30+0.26 ρJup) that suggests an enrichment of the planet in heavy elements. The planet WASP-88 bis a 0.56 ± 0.08 MJuphot Jupiter orbiting a V = 11.4 F6-type star (1.45 ± 0.05 M⊙, 2.08-0.06+0.12 R⊙, Teff = 6431 ± 130 K) with a period of 4.954000 ± 0.000019 days. With a radius of 1.70-0.07+0.13 RJup, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5–7.0 Gyr for WASP-68, 2.8-5.7 Gyr for WASP-73 and 1.8–4.3 Gyr for WASP-88. The star WASP-73 appears to be significantly evolved, close to or already in the subgiant phase. The stars WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning.Publisher PDFPeer reviewe
Understanding the water emission in the mid- and far-IR from protoplanetary disks around T Tauri stars

The research leading to these results has received funding from the European Union Seventh Framework Programme FP7-2011 under grant agreement no 284405.Aims. We investigate which properties of protoplanetary disks around T Tauri stars affect the physics and chemistry in the regions where mid- and far-IR water lines originate and their respective line fluxes. We search for diagnostics for future observations. Methods. With the code ProDiMo, we build a series of models exploring a large parameter space, computing rotational and ro-vibrational transitions of water in nonlocal thermodynamic equilibrium (non-LTE). We select a sample of transitions in the mid-IR regime and the fundamental ortho and para water transitions in the far-IR. We investigate the chemistry and the local physical conditions in the line emitting regions. We calculate Spitzer spectra for each model and compare far-IR and mid-IR lines. In addition, we use mid-IR colors to tie the water line predictions to the dust continuum. Results. Parameters affecting the water line fluxes in disks by more than a factor of three are: the disk gas mass, the dust-to-gas mass ratio, the dust maximum grain size, interstellar medium (ISM) UV radiation field, the mixing parameter of Dubrulle settling, the disk flaring parameter, and the dust size distribution. The first four parameters affect the mid-IR lines much more than the far-IR lines. Conclusions. A key driver behind water spectroscopy is the dust opacity, which sets the location of the water line emitting region. We identify three types of parameters, including those (1) affecting global disk opacity and opacity function (maximum dust size and dust size distribution); (2) affecting global disk opacity (dust-to-gas mass ratio, Dubrulle settling, disk gas mass); and (3) not affecting disk opacity (flaring parameter, ISM UV radiation field, fraction of PAHs). Parameters, such as dust-to-gas ratio, ISM radiation field, and dust size distribution, affect the mid-IR lines more, while the far-IR transitions are more affected by the flaring index. The gas mass greatly affects lines in both regimes. Higher spectral resolution and line sensitivities, like from the James Webb Space Telescope, are needed to detect a statistically relevant sample of individual water lines to distinguish further between these types of parameters.Publisher PDFPeer reviewe
Effects of hyperbaric oxygen preconditioning on cardiac stress markers after simulated diving.

Hyperbaric oxygen preconditioning (HBO-PC) can protect the heart from injury during subsequent ischemia. The presence of high loads of venous gas emboli (VGE) induced by a rapid ambient pressure reduction on ascent from diving may cause ischemia and acute heart failure. The aim of this study was to investigate the effect of diving-induced VGE formation on cardiac stress marker levels and the cardioprotective effect of HBO-PC. To induce high loads of VGE, 63 female Sprague-Dawley rats were subjected to a rapid ambient pressure reduction from a simulated saturation dive (50 min at 709 kPa) in a pressure chamber. VGE loads were measured for 60 min in anesthetized animals by the use of ultrasonography. The animals were divided into five groups. Three groups were exposed to either diving or to HBO-PC (100% oxygen, 38 min at 303 kPa) with a 45 or 180 min interval between HBO-PC and diving. Two additional groups were used as baseline controls for the measurements; one group was exposed to equal handling except for HBO-PC and diving, and the other group was completely unexposed. Diving caused high loads of VGE, as well as elevated levels of the cardiac stress markers, cardiac troponin T (cTnT), natriuretic peptide precursor B (Nppb), and αB-crystallin, in blood and cardiac tissue. There were strong positive correlations between VGE loads and stress marker levels after diving, and HBO-PC appeared to have a cardioprotective effect, as indicated by the lower levels of stress marker expression after diving-induced VGE formation. 


KEYWORDS: 

Cardioprotection, decompression illness, diving, gas embolism, hyperbaric oxygen preconditionin
Adipose-derived stem cells from the brown bear (Ursus arctos) spontaneously undergo chondrogenic and osteogenic differentiation

In the den, hibernating brown bears do not develop tissue atrophy or organ damage, despite
almost no physical activity. Mesenchymal stem cells could play an important role in tissue repair and
regeneration in brown bears. Our objective was to determine if adipose tissue-derived stem cells
(ASCs) can be recovered from adipose tissue of wild Scandinavian brown bears and characterize
osteogenic, chondrogenic, and adipogenic differentiation in the cells. Following immobilization of 8
wild brown bears 7-10 days after leaving the den in mid-April, adipose tissue biopsies (5-8 ml) were
obtained subcutaneously from 7 bears. ASCs were recovered and characterized. Adipose stem cell
cultures were established from 6 of 7 bears. Adipose tissue-derived stem cells from yearlings
spontaneously formed bone-like nodules surrounded by cartilaginous deposits, suggesting
differentiation into osteogenic and chondrogenic lineages. This ability appears to be lost gradually with
age. This is the first study to demonstrate stem cell recovery and growth from brown bears, and it is
the first report of ASCs spontaneously differentiating into osteocytes and chondrocytes. These findings
could have implications for the use of hibernating brown bears as a model to study osteoporosis
Chern-Simons theory as the large-mass limit of topologically massive Yang-Mills theory

We study quantum Chern-Simons theory as the large-mass limit of the limit D --> 3 of dimensionally regularized topologically massive Yang-Mills theory. This approach can also be interpreted as a BRS-invariant hybrid regularization of Chern-Simons theory, consisting of a higher-covariant derivative Yang-Mills term plus dimensional regularization. Working in the Landau gauge, we compute radiative corrections up to second order in perturbation theory and show that there is no two-loop correction to the one-loop shift k --> k + c(v), k being the bare Chern-Simons parameter. In passing, we also prove by explicit computation that topologically massive Yang Mills theory is UV finite