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The novel missense mutation Met48Lys in FKBP22 changes its structure and functions.
Mutations in the FKBP14 gene encoding FKBP22 (FK506 Binding Protein 22 kDa) cause kyphoscoliotic Ehlers-Danlos Syndrome (kEDS). The first clinical report showed that a lack of FKBP22 protein due to mutations causing nonsense-mediated decay of the mRNA leads to a wide spectrum of clinical phenotypes including progressive kyphoscoliosis, joint hypermobility, hypotonia, hyperelastic skin, hearing loss and aortic rupture. Our previous work showed that these phenotypic features could be correlated with the functions of FKBP22, which preferentially binds to type III, VI and X collagens, but not to type I, II or V collagens. We also showed that FKBP22 catalyzed the folding of type III collagen through its prolyl isomerase activity and acted as a molecular chaperone for type III collagen. Recently, a novel missense mutation Met48Lys in FKBP22 was identified in a patient with kEDS. In this report, we expand the list of substrates of FKBP22 and also demonstrate that the Met48Lys mutation diminishes the activities of FKBP22, indicating that pathology can arise from absence of FKBP22, or partial loss of its function
Gestión de la investigación en la Universidad Nacional de Cuyo (1949-2010)
La Universidad Nacional de Cuyo, desde su origen, consideró a la investigación como una de sus funciones básicas. En tal sentido este libro surge como una propuesta para sistematizar, preservar y difundir información institucional, relacionada a la gestión del área específica. La Secretaría de Ciencia, Técnica y Posgrado de esta Casa de Estudios, a fines de 2009, invitó a participar de la iniciativa a quienes fueron responsables de esta tarea y a investigadores interesados en la historia de la institución, los que aportaron información y el valor de su experiencia.
En el desarrollo de la obra se puede verificar claramente la evolución de estructuras y la definición de políticas científicas desarrolladas en la UNCuyo, ligadas a momentos históricos, políticas nacionales, locales e institucionales. Del relato de cada autor se observa que: planificación, mecanismos y estrategias de promoción de la investigación manifiestan una continuidad de esfuerzos cuyo objeto es incentivar la producción del conocimiento y su transferencia a las aulas y al medio.
De la compiladora de la obra: Patricia Pons, Licenciada en Ciencias De la Educación de la Pontificia Universidad Católica Argentina Santa María de los Buenos Aires; se encuentra en la etapa de finalización de sus estudios de Maestría en Gestión de la Ciencia, la Técnica y la Innovación de la Universidad Nacional de General Sarmiento; Directora General de Ciencia y Técnica de la Secretaría de Ciencia Técnica y Posgrado de la Universidad Nacional de Cuyo
X-ray Pulsations from the region of the Supergiant Fast X-ray Transient IGR J17544-2619
Phase-targeted RXTE observations have allowed us to detect a transient 71.49
\pm 0.02 s signal that is most likely to be originating from the supergiant
fast X-ray transient IGR J17544-2619. The phase-folded light curve shows a
possible double-peaked structure with a pulsed flux of ~4.8*10^-12 erg cm^-2
s^-1 (3-10 keV). Assuming the signal to indicate the spin period of the neutron
star in the system, the provisional location of IGR J17544-2619 on the Corbet
diagram places the system within the classical wind-fed supergiant XRB region.
Such a result illustrates the growing trend of supergiant fast X-ray transients
to span across both of the original classes of HMXB in Porb - Pspin space.Comment: 7 pages, 6 figures, Accepted for publication in Astronomy and
Astrophysics main journa
Ferromagnetism in Oriented Graphite Samples
We have studied the magnetization of various, well characterized samples of
highly oriented pyrolitic graphite (HOPG), Kish graphite and natural graphite
to investigate the recently reported ferromagnetic-like signal and its possible
relation to ferromagnetic impurities. The magnetization results obtained for
HOPG samples for applied fields parallel to the graphene layers - to minimize
the diamagnetic background - show no correlation with the magnetic impurity
concentration. Our overall results suggest an intrinsic origin for the
ferromagnetism found in graphite. We discuss possible origins of the
ferromagnetic signal.Comment: 11 figure
Measurement of the hadronic photon structure function F_{2}^{γ} at LEP2
The hadronic structure function of the photon F_{2}^{γ} (x, Q²) is measured as a function of Bjorken x and of the photon virtuality Q² using deep-inelastic scattering data taken by the OPAL detector at LEP at e⁺e⁻ centre-of-mass energies from 183 to 209 GeV. Previous OPAL measurements of the x dependence of F_{2}^{γ} are extended to an average Q² of 〈Q²〉=780 GeV² using data in the kinematic range 0.15<x<0.98. The Q² evolution of F_{2}^{γ} is studied for 12.1<〈Q²〉<780 GeV² using three ranges of x. As predicted by QCD, the data show positive scaling violations in F_{2}^{γ} with F_{2}^{γ} (Q²)/α = (0.08±0.02⁺⁰·⁰⁵_₀.₀₃) + (0.13±0.01⁺⁰·⁰¹_₀.₀₁) lnQ², where Q² is in GeV², for the central x region 0.10–0.60. Several parameterisations of F_{2}^{γ} are in qualitative agreement with the measurements whereas the quark-parton model prediction fails to describe the data
The 2015-2016 outburst of the classical EXor V1118 Ori
After a quiescence period of about 10 years, the classical EXor source V1118
Ori has undergone an accretion outburst in 2015 September. The maximum
brightness (DV > 4 mag) was reached in 2015 December and was maintained for
several months. Since 2016 September, the source is in a declining phase.
Photometry and low/ high-resolution spectroscopy were obtained with MODS and
LUCI2 at the {\it Large Binocular Telescope}, with the facilities at the Asiago
1.22 and 1.82 m telescopes, and with GIANO at the {\it Telescopio Nazionale
Galileo}. The spectra are dominated by emission lines of \hi\ and neutral
metallic species. From line and continuum analysis we derive the mass accretion
rate and its evolution during the outburst. Considering that extinction may
vary between 1.5 and 2.9 mag, we obtain m_acc= 0.32.0 10 m_sun/yr, in
quiescence and m_acc= 0.21.9 10 m_sun/yr, at the outburst peak. The
Balmer decrement shape has been interpreted by means of line excitation models,
finding that from quiescence to outburst peak, the electron density has
increased from 2 10 cm to 4 10 cm. The
profiles of the metallic lines are symmetric and narrower than 100 km s,
while \hi\, and \hei\,\,lines show prominent wings extending up to 500 km
s. The metallic lines likely originate at the base of the accretion
columns, where neutrals are efficiently shielded against the ionizing photons,
while faster ionized gas is closer to the star. Outflowing activity is
testified by the detection of a variable P Cyg-like profile of the H
and \hei\, 1.08\,m lines.Comment: Accepted by Ap
The Diagnostic Potential of Transition Region Lines under-going Transient Ionization in Dynamic Events
We discuss the diagnostic potential of high cadence ultraviolet spectral data
when transient ionization is considered. For this we use high cadence UV
spectra taken during the impulsive phase of a solar flares (observed with
instruments on-board the Solar Maximum Mission) which showed excellent
correspondence with hard X-ray pulses. The ionization fraction of the
transition region ion O V and in particular the contribution function for the O
V 1371A line are computed within the Atomic Data and Analysis Structure, which
is a collection of fundamental and derived atomic data and codes which
manipulate them. Due to transient ionization, the O V 1371A line is enhanced in
the first fraction of a second with the peak in the line contribution function
occurring initially at a higher electron temperature than in ionization
equilibrium. The rise time and enhancement factor depend mostly on the electron
density. The fractional increase in the O V 1371A emissivity due to transient
ionization can reach a factor of 2--4 and can explain the fast response in the
line flux of transition regions ions during the impulsive phase of flares
solely as a result of transient ionization. This technique can be used to
diagnostic the electron temperature and density of solar flares observed with
the forth-coming Interface Region Imaging Spectrograph.Comment: 18 pages, 6 figure
Colour reconnection in e+e- -> W+W- at sqrt(s) = 189 - 209 GeV
The effects of the final state interaction phenomenon known as colour
reconnection are investigated at centre-of-mass energies in the range sqrt(s) ~
189-209 GeV using the OPAL detector at LEP. Colour reconnection is expected to
affect observables based on charged particles in hadronic decays of W+W-.
Measurements of inclusive charged particle multiplicities, and of their angular
distribution with respect to the four jet axes of the events, are used to test
models of colour reconnection. The data are found to exclude extreme scenarios
of the Sjostrand-Khoze Type I (SK-I) model and are compatible with other
models, both with and without colour reconnection effects. In the context of
the SK-I model, the best agreement with data is obtained for a reconnection
probability of 37%. Assuming no colour reconnection, the charged particle
multiplicity in hadronically decaying W bosons is measured to be (nqqch) =
19.38+-0.05(stat.)+-0.08 (syst.).Comment: 30 pages, 9 figures, Submitted to Euro. Phys. J.
Search for Second-Generation Scalar Leptoquarks in Collisions at =1.96 TeV
Results on a search for pair production of second generation scalar
leptoquark in collisions at =1.96 TeV are reported. The
data analyzed were collected by the CDF detector during the 2002-2003 Tevatron
Run II and correspond to an integrated luminosity of 198 pb. Leptoquarks
(LQ) are sought through their decay into (charged) leptons and quarks, with
final state signatures represented by two muons and jets and one muon, large
transverse missing energy and jets. We observe no evidence for production
and derive 95% C.L. upper limits on the production cross sections as well
as lower limits on their mass as a function of , where is the
branching fraction for .Comment: 9 pages (3 author list) 5 figure
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
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