689 research outputs found
Non-Invasive Mouse Models of Post-Traumatic Osteoarthritis
SummaryAnimal models of osteoarthritis (OA) are essential tools for investigating the development of the disease on a more rapid timeline than human OA. Mice are particularly useful due to the plethora of genetically modified or inbred mouse strains available. The majority of available mouse models of OA use a joint injury or other acute insult to initiate joint degeneration, representing post-traumatic osteoarthritis (PTOA). However, no consensus exists on which injury methods are most translatable to human OA. Currently, surgical injury methods are most commonly used for studies of OA in mice; however, these methods may have confounding effects due to the surgical/invasive injury procedure itself, rather than the targeted joint injury. Non-invasive injury methods avoid this complication by mechanically inducing a joint injury externally, without breaking the skin or disrupting the joint. In this regard, non-invasive injury models may be crucial for investigating early adaptive processes initiated at the time of injury, and may be more representative of human OA in which injury is induced mechanically. A small number of non-invasive mouse models of PTOA have been described within the last few years, including intra-articular fracture of tibial subchondral bone, cyclic tibial compression loading of articular cartilage, and anterior cruciate ligament (ACL) rupture via tibial compression overload. This review describes the methods used to induce joint injury in each of these non-invasive models, and presents the findings of studies utilizing these models. Altogether, these non-invasive mouse models represent a unique and important spectrum of animal models for studying different aspects of PTOA
Implementation of a Markov Chain Monte Carlo method to inorganic aerosol modeling of observations from the MCMA-2003 campaign ? Part II: Model application to the CENICA, Pedregal and Santa Ana sites
International audienceA Markov Chain Monte Carlo model for integrating the observations of inorganic species with a thermodynamic equilibrium model was presented in Part I of this series. Using observations taken at three ground sites, i.e. a residential, industrial and rural site, during the MCMA-2003 campaign in Mexico City, the model is used to analyze the inorganic particle and ammonia data and to predict gas phase concentrations of nitric and hydrochloric acid. In general, the model is able to accurately predict the observed inorganic particle concentrations at all three sites. The agreement between the predicted and observed gas phase ammonia concentration is excellent. The NOz concentration calculated from the NOy, NO and NO2 observations is of limited use in constraining the gas phase nitric acid concentration given the large uncertainties in this measure of nitric acid and additional reactive nitrogen species. Focusing on the acidic period of 9?11 April identified by Salcedo et al. (2006), the model accurately predicts the particle phase observations during this period with the exception of the nitrate predictions after 10:00 a.m. (Central Daylight Time, CDT) on 9 April, where the model underpredicts the observations by, on average, 20%. This period had a low planetary boundary layer, very high particle concentrations, and higher than expected nitrogen dioxide concentrations. For periods when the particle chloride observations are consistently above the detection limit, the model is able to both accurately predict the particle chloride mass concentrations and provide well-constrained HCl (g) concentrations. The availability of gas-phase ammonia observations helps constrain the predicted HCl (g) concentrations. When the particles are aqueous, the most likely concentrations of HCl (g) are in the sub-ppbv range. The most likely predicted concentration of HCl (g) was found to reach concentrations of order 10 ppbv if the particles are dry. Finally, the atmospheric relevance of HCl (g) is discussed in terms of its indicator properties for the possible influence of chlorine-mediated photochemistry in Mexico City
The anti-NGF antibody muMab 911 both prevents and reverses pain behaviour and subchondral osteoclast numbers in a rat model of osteoarthritis pain
Objective: Nerve growth factor (NGF) has a pivotal role in peripheral hyperalgesia and inflammation; anti-NGF antibodies attenuate pain responses in inflammatory pain models, and in people with osteoarthritis (OA) or low back pain. The aim of this study was to characterise the peripheral mechanisms contributing to the analgesic effects of anti-NGF antibody treatment in an established model of joint pain, which mimics key clinical features of OA.
Design: Effects of preventative vs therapeutic treatment with an anti-NGF antibody (monoclonal antibody 911: muMab 911 (10 mg/kg, s.c.)) on pain behaviour (weight bearing asymmetry and hindpaw withdrawal thresholds (PWT)), cartilage damage, synovitis and numbers of subchondral osteoclasts were investigated in the monosodium iodoacetate (MIA) model. Potential direct effects of NGF on receptor activator of nuclear factor kappa-B ligand (RANKL) mediated osteoclastogenesis were investigated in cultured human osteoclasts.
Results: Intra-articular MIA injection resulted in significant pain behaviour, cartilage damage, synovitis and increased numbers of subchondral osteoclasts. Both preventative and therapeutic treatment with muMab 911 significantly prevented, or reversed, MIA-induced pain behaviour, but did not alter cartilage or synovial pathology quantified at the end of the treatment period. NGF did not facilitate RANKL driven osteoclast differentiation in vitro, but preventative or therapeutic muMab 911 reduced numbers of TRAP positive osteoclasts in the subchondral bone.
Conclusions: We demonstrate that anti-NGF antibody treatment attenuates OA pain behaviour despite permitting cartilage damage and synovitis. Indirec
Stellar evolution and modelling stars
In this chapter I give an overall description of the structure and evolution
of stars of different masses, and review the main ingredients included in
state-of-the-art calculations aiming at reproducing observational features. I
give particular emphasis to processes where large uncertainties still exist as
they have strong impact on stellar properties derived from large compilations
of tracks and isochrones, and are therefore of fundamental importance in many
fields of astrophysics.Comment: Lecture presented at the IVth Azores International Advanced School in
Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars
and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta,
Azores Islands, Portugal in July 201
The southern photometric local universe survey (S-PLUS): Improved SEDs, morphologies, and redshifts with 12 optical filters
The Southern Photometric Local Universe Survey (S-PLUS) is imaging ~9300 deg2 of the celestial sphere in 12 optical bands using a dedicated 0.8mrobotic telescope, the T80-South, at the Cerro Tololo Inter-american Observatory, Chile. The telescope is equipped with a 9.2k × 9.2k e2v detector with 10 μm pixels, resulting in a field of view of 2 deg2 with a plate scale of 0.55 arcsec pixel-1. The survey consists of four main subfields, which include two non-contiguous fields at high Galactic latitudes (|b| > 30° , 8000 deg2) and two areas of the Galactic Disc and Bulge (for an additional 1300 deg2). S-PLUS uses the Javalambre 12-band magnitude system, which includes the 5 ugriz broad-band filters and 7 narrow-band filters centred on prominent stellar spectral features: the Balmer jump/[OII], Ca H + K, Hd, G band, Mg b triplet, Hα, and the Ca triplet. S-PLUS delivers accurate photometric redshifts (δz/(1 + z) = 0.02 or better) for galaxies with r < 19.7 AB mag and z < 0.4, thus producing a 3D map of the local Universe over a volume of more than 1 (Gpc/h)3. The final S-PLUS catalogue will also enable the study of star formation and stellar populations in and around the Milky Way and nearby galaxies, as well as searches for quasars, variable sources, and low-metallicity stars. In this paper we introduce the main characteristics of the survey, illustrated with science verification data highlighting the unique capabilities of S-PLUS. We also present the first public data release of ~336 deg2 of the Stripe 82 area, in 12 bands, to a limiting magnitude of r = 21, available at datalab.noao.edu/splus.Fil: De Oliveira, C. Mendes. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Ribeiro, T.. Universidade Federal de Sergipe; Brasil. National Optical Astronomy Observatory; Estados UnidosFil: Schoenell, W.. Universidade Federal do Rio Grande do Sul; BrasilFil: Kanaan, A.. Universidade Federal de Santa Catarina; BrasilFil: Overzier, R.A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; Brasil. Ministério da Ciência, Tecnologia, Inovação e Comunicações. Observatório Nacional; BrasilFil: Molino, A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Sampedro, L.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Coelho, P.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Barbosa, C.E.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Cortesi, A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Costa Duarte, M.V.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Herpich, F.R.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; Brasil. Universidade Federal de Santa Catarina; BrasilFil: Hernandez Jimenez, J.A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Placco, V.M.. University of Notre Dame; Estados Unidos. JINA Center for the Evolution of the Elements ; Estados UnidosFil: Xavier, H.S.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Abramo, L.R.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Saito, R.K.. Universidade Federal de Santa Catarina; BrasilFil: Chies Santos, A.L.. Universidade Federal do Rio Grande do Sul; BrasilFil: Ederoclite, A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; Brasil. Centro de Estudios de Física del Cosmo de Aragon; EspañaFil: De Oliveira, R. Lopes. Universidade Federal de Sergipe; Brasil. Ministério da Ciência, Tecnologia, Inovação e Comunicações. Observatório Nacional; Brasil. University of Maryland; Estados UnidosFil: Goncalves, D.R.. Universidade Federal do Rio de Janeiro; BrasilFil: Akras, S.. Ministério da Ciência, Tecnologia, Inovação e Comunicações. Observatório Nacional; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Almeida, L.A.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; Brasil. Universidade Federal do Rio Grande do Norte; BrasilFil: Almeida Fernandes, F.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Beers, T.C.. University of Notre Dame; Estados Unidos. JINA Center for the Evolution of the Elements ; Estados UnidosFil: Bonatto, C.. Universidade Federal do Rio Grande do Sul; BrasilFil: Bonoli, S.. Centro de Estudios de Física del Cosmo de Aragon; EspañaFil: Cypriano, E.S.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Vinicius Lima, E.. Universidade do Sao Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas; BrasilFil: Smith Castelli, Analia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentin
Toward an internally consistent astronomical distance scale
Accurate astronomical distance determination is crucial for all fields in
astrophysics, from Galactic to cosmological scales. Despite, or perhaps because
of, significant efforts to determine accurate distances, using a wide range of
methods, tracers, and techniques, an internally consistent astronomical
distance framework has not yet been established. We review current efforts to
homogenize the Local Group's distance framework, with particular emphasis on
the potential of RR Lyrae stars as distance indicators, and attempt to extend
this in an internally consistent manner to cosmological distances. Calibration
based on Type Ia supernovae and distance determinations based on gravitational
lensing represent particularly promising approaches. We provide a positive
outlook to improvements to the status quo expected from future surveys,
missions, and facilities. Astronomical distance determination has clearly
reached maturity and near-consistency.Comment: Review article, 59 pages (4 figures); Space Science Reviews, in press
(chapter 8 of a special collection resulting from the May 2016 ISSI-BJ
workshop on Astronomical Distance Determination in the Space Age
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
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