Abstract Duchenne muscular dystrophy (DMD) is a recessive X-linked form of muscular dystrophy characterized by progressive and irreversible degeneration of the muscles. The mdx mouse is the classical ...animal model for DMD, showing similar molecular and protein defects. The mdx mouse, however, does not show significant muscle weakness, and the diaphragm muscle is significantly more degenerated than skeletal muscles. In this work,1 H magnetic resonance spectroscopy (MRS) was used to study the metabolic profile of quadriceps and diaphragm muscles from mdx and control mice. Using principal components analysis (PCA), the animals were separated into groups according to age and lineages. The classification was compared to histopathological analysis. Among the 24 metabolites identified from the nuclear MR spectra, only 19 were used by the PCA program for classification purposes. These can be important key biomarkers associated with the progression of degeneration in mdx muscles and with natural aging in control mice. Glutamate, glutamine, succinate, isoleucine, acetate, alanine and glycerol were increased in mdx samples as compared to control mice, in contrast to carnosine, taurine, glycine, methionine and creatine that were decreased. These results suggest that MRS associated with pattern recognition analysis can be a reliable tool to assess the degree of pathological and metabolic alterations in the dystrophic tissue, thereby affording the possibility of evaluation of beneficial effects of putative therapies.
We describe the method of measuring the integrated luminosity of the e+e- collider DAΦNE, the Frascati φ-factory. The measurement is done with the KLOE detector selecting large angle Bhabha ...scattering events and normalizing them to the effective cross section. The e+e-→e+e-(γ) cross section is calculated using different event generators which account for the \(\mathcal{O}(\alpha)\) radiative initial and final state corrections, and the φ resonance contribution. The accuracy of the measurement is 0.6%, where 0.3% comes from systematic errors related to the event counting and 0.5% from theoretical evaluations of the cross section.
Using a sample of over 400 million φ→KSKL decays produced during the years 2001 and 2002 at the DAΦNE e+e- collider, the ratio RSπ=Γ(KS→π+π-(γ))/Γ(KS→π0π0) has been measured with the KLOE detector. ...The result is RSπ=2.2555±0.0012stat±0.0021corr-stat±0.0050syst, which is in good agreement with the previously published result based on the KLOE data sample from the year 2000. The average of the KLOE results is RSπ=2.2549±0.0054, reducing the total error by a factor of three, to 0.25%.
We have measured the ratio σ(e+e−→π+π−γ)/σ(e+e−→μ+μ−γ), with the KLOE detector at DAΦNE for a total integrated luminosity of ∼240 pb−1. From this ratio we obtain the cross section σ(e+e−→π+π−). From ...the cross section we determine the pion form factor |Fπ|2 and the two-pion contribution to the muon anomaly aμ for 0.592<Mππ<0.975 GeV, Δππaμ=(385.1±1.1stat±2.7sys+theo)×10−10. This result confirms the current discrepancy between the Standard Model calculation and the experimental measurement of the muon anomaly.
The effect of carbon black and ceramic (α-Al
2O
3 and γ-Al
2O
3) particles on the cationic and polymer chain mobility have been investigated in poly(ethylene oxide)–lithium salt (LiClO
4 and LiBF
4) ...solid composite polymer electrolytes by using nuclear magnetic resonance (NMR) techniques. Proton (
1H) and lithium (
7Li) lineshapes and spin–lattice relaxation times were measured as a function of temperature. The
7Li data indicates that the lineshape and relaxation is affected by the coupling of its quadrupolar moment to the surrounding electric field gradients. Activation energies extracted from the
7Li relaxation data are in the range 0.20–0.25 eV. Results show that the addition of α-Al
2O
3 influenced both, the relative cation mobility and the polymer chain motion. Calculation shows that this result is in quantitative agreement with the conductivity data.
A detailed description of the thermal relaxation processes in MEH−PPV is reported. Bulk methods such as DMTA were employed in conjunction with other techniques that probe molecular motions, such as ...fluorescence spectroscopy, thermal stimulated current, and 13C NMR. From the two main transitions observed (glass transition process at 340 K and β-relaxation between 200 and 220 K), it was demonstrated that the first is strongly correlated with the dissociation of a fluorescent emissive interchain complex and that the second relaxation involves movements of the lateral substituents of the polymer backbone and, more specifically, their CH2 groups. NMR dipolar chemical shift correlation experiments pointed an increasing gain in mobility through the side chain, the lateral carbons close to the aromatic ring being more rigid than those located more distant from the main polymer chain. A kinetic model involving the dissociation of interchains to re-form intrachain excitons was proposed to explain the profiles of the photoluminescence spectra at higher temperatures.
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