845 research outputs found
Osteopontin ablation ameliorates muscular dystrophy by shifting macrophages to a pro-regenerative phenotype.
In the degenerative disease Duchenne muscular dystrophy, inflammatory cells enter muscles in response to repetitive muscle damage. Immune factors are required for muscle regeneration, but chronic inflammation creates a profibrotic milieu that exacerbates disease progression. Osteopontin (OPN) is an immunomodulator highly expressed in dystrophic muscles. Ablation of OPN correlates with reduced fibrosis and improved muscle strength as well as reduced natural killer T (NKT) cell counts. Here, we demonstrate that the improved dystrophic phenotype observed with OPN ablation does not result from reductions in NKT cells. OPN ablation skews macrophage polarization toward a pro-regenerative phenotype by reducing M1 and M2a and increasing M2c subsets. These changes are associated with increased expression of pro-regenerative factors insulin-like growth factor 1, leukemia inhibitory factor, and urokinase-type plasminogen activator. Furthermore, altered macrophage polarization correlated with increases in muscle weight and muscle fiber diameter, resulting in long-term improvements in muscle strength and function in mdx mice. These findings suggest that OPN ablation promotes muscle repair via macrophage secretion of pro-myogenic growth factors
A K=3 two-quasiparticle isomer in Sr
The decay of on-line mass-separated
98
Rb
to
98
Sr
is studied by
γ
spectroscopy. The revised decay scheme adds further evidence of the coexistence of very different shapes in
98
Sr
.
A set of levels is proposed to originate from particle-hole pair excitations across the
Z
=
40
spherical gap in analogy with
96
Sr
.
A deformed
K
=
3
band with probable even parity is built on a 7.1-ns isomer at 1838 keV. It is interpreted as a two-quasineutron excitation in accordance with a quantum Monte Carlo pairing calculation based on a deformed shell model. Configurations of the calculated lowest-lying two-quasiparticle levels confirm the importance of the [404]9/2 neutron orbital at the largest deformations in the neutron-rich
A
≃
100
region
Cuban creole pig in Bayamo jurisdiction
The former jurisdiction of Bayamo, as political colonial division began its way in the century XVI, after its foundation in 1513 as the second Cuban village. Currently the Bayamo village is integrated by 15 local districts, an extension of 835.12 km2 and a population 68690 inhabitants. In spite of have elapsed more than 470 years from the arrival of the first pigs from Spain, this region has maintained 6176 breeders of this native pig breed as direct descendant of the Mediterranean pigs. In this work is presented the racial, ecological and human factors, that they have permitted the maintenance of this population with origin in the Iberian pig.La antigua jurisdicción de Bayamo, como división política de la colonia comenzó su andadura en el siglo XVI, tras su fundación en 1513 como la segunda villa de Cuba. Actualmente el municipio de Bayamo lo integran 15 consejos populares, una superficie de 835,12 km2 y una población de 68690 habitantes. A pesar de haber transcurrido más de 470 años desde la llegada de los primeros cerdos desde España, esta región ha mantenido 6176 reproductores de la raza cerdo Criollo como descendiente directo de los cerdos mediterráneos. En este trabajo se presenta los factores racial, ecológico y humano, que han permitido la perdurabilidad de esta raza descendiente del cerdo Ibérico
Measurements of high-energy neutron-induced fission of natPb and 209Bi
EFNUDAT – Measurements and Models of Nuclear ReactionsThe CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure low cross sections as those of neutron-induced fission in subactinides. The cross section ratios of natPb and 209Bi relative to 235U and 238U were measured using PPAC detectors and a fragment coincidence method that allows us to identify the fission events. The present experiment provides first results for neutron-induced fission up to 1 GeV. Good agreement is found with previous experimental data below 200 MeV. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross sections is close to 1 Ge
DEFORMATION DEPENDENT TUL MULTI-STEP DIRECT MODEL
The Multi-Step Direct (MSD) module TRISTAN in the nuclear reaction code EMPIRE has been extended in order to account for nuclear deformation. The new formalism was tested in calculations of neutron emission spectra emitted from the {sup 232}Th(n,xn) reaction. These calculations include vibration-rotational Coupled Channels (CC) for the inelastic scattering to low-lying collective levels, ''deformed'' MSD with quadrupole deformation for inelastic scattering to the continuum, Multi-Step Compound (MSC) and Hauser-Feshbach with advanced treatment of the fission channel. Prompt fission neutrons were also calculated. The comparison with experimental data shows clear improvement over the ''spherical'' MSD calculations and JEFF-3.1 and JENDL-3.3 evaluations
The 93Zr(n, γ) reaction up to 8 keV neutron energy
The (n,γ) reaction of the radioactive isotope 93Zr has been measured at the n-TOF high-resolution time-of-flight facility at CERN. Resonance parameters have been extracted in the neutron energy range up to 8 keV, yielding capture widths smaller (14%) than reported in an earlier experiment. These results are important for detailed nucleosynthesis calculations and for refined studies of waste transmutation concepts.EC FIKW-CT-2000-0010
Osteopontin ablation ameliorates muscular dystrophy by shifting macrophages to a proregenerative phenotype
In the degenerative disease Duchenne muscular dystrophy, inflammatory cells enter muscles in response to repetitive muscle damage. Immune factors are required for muscle regeneration, but chronic inflammation creates a profibrotic milieu that exacerbates disease progression. Osteopontin (OPN) is an immunomodulator highly expressed in dystrophic muscles. Ablation of OPN correlates with reduced fibrosis and improved muscle strength as well as reduced natural killer T (NKT) cell counts. Here, we demonstrate that the improved dystrophic phenotype observed with OPN ablation does not result from reductions in NKT cells. OPN ablation skews macrophage polarization toward a pro-regenerative phenotype by reducing M1 and M2a and increasing M2c subsets. These changes are associated with increased expression of pro-regenerative factors insulin-like growth factor 1, leukemia inhibitory factor, and urokinase-type plasminogen activator. Furthermore, altered macrophage polarization correlated with increases in muscle weight and muscle fiber diameter, resulting in long-term improvements in muscle strength and function in mdx mice. These findings suggest that OPN ablation promotes muscle repair via macrophage secretion of pro-myogenic growth factors
Neutron-induced fission cross section of 245 Cm: New results from data taken at the time-of-flight facility n_TOF
The neutron-induced fission cross section of 245Cm was measured at n-TOF in a wide energy range and with high resolution. The energy dependence, measured in a single measurement from 30 meV to 1 MeV neutron energy, has been determined with 5% accuracy relative to the 235U(n,f) cross section. In order to reduce the uncertainty on the absolute value, the data have been normalized at thermal energy to recent measurements performed at ILL and BR1. In the energy range of overlap, the results are in fair agreement with some previous measurements and confirm, on average, the evaluated cross section in the ENDF/B-VII.0 database, although sizable differences are observed for some important resonances below 20 eV. A similar behavior is observed relative to JENDL/AC-2008, a reactor-oriented database for actinides. The new results contribute to the overall improvement of the databases needed for the design of advanced reactor systems and may lead to refinements of fission models for the actinides.Comisión Europea FIKW-CT-2000-00107 24967
Measurement of the radiative neutron capture cross section of 206 Pb and its astrophysical implications
The (n,γ) cross section of 206Pb has been measured at the CERN n_TOF facility with high resolution in the energy range from 1 eV to 620 keV by using two optimized 6C6D detectors. In the investigated energy interval about 130 resonances could be observed, from which 61 had enough statistics to be reliably analyzed via the R-matrix analysis code SAMMY. Experimental uncertainties were minimized, in particular with respect to (i) angular distribution effects of the prompt capture γ-rays, and to (ii) the TOF-dependent background due to sample-scattered neutrons. Other background components were addressed by background measurements with an enriched 208Pb sample. The effect of the lower energy cutoff in the pulse height spectra of the 6C6D detectors was carefully corrected via Monte Carlo simulations. Compared to previous 206Pb values, the Maxwellian averaged capture cross sections derived from these data are about 20% and 9% lower at thermal energies of 5 keV and 30 keV, respectively. These new results have a direct impact on the s-process abundance of 206Pb, which represents an important test for the interpretation of the cosmic clock based on the decay of 238U
The 139 La(n ,γ) cross section: Key for the onset of the s -process
The nuclear resonance parameters and the capture cross section of the neutron magic isotope La139 have been measured relative to Au197 in the energy range of 0.6 eV to 9 keV at the neutron time-of-flight (n_TOF) facility at CERN. We describe the experimental apparatus and the data analysis procedures, which concerned mainly the efficiency correction by means of the pulse height weighting function technique and the determination of different background components. We extracted the resonance parameters and the main nuclear quantities such as the resonance integral RI=10.8±1.0b, the average widths for s and p waves a 1=0=50.7 5.4 meV and l=1=33. 6±6.9 meV, the nuclear level densities l=0=252A 22 eV and l=1<250 eV, and the neutron strength functions S0=(0.82±0.05) Ö10-4 and S1=(0.55±0.04)Ö10-4. These results represent a significant improvement over previous data. The deduced Maxwellian-averaged capture cross sections are important for the interpretation of the most recent spectroscopic observations in low-metallicity stars.EC FIKW-CT-2000-0010
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