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The 12C(18O, 16O) 14C and C(18O, 17O) 14C reactions were studied at INFN-LNS laboratory in Catania. The experiments were performed using an 18O Tandem beam at 84 MeV incident energy. Charged ejectiles produced in the reactions were momentum analyzed and identified by the MAGNEX spectrometer. Q-value spectra were extracted with a remarkable energy resolution (FWHM ~ 150 keV) and several known bound and resonant states were identified. In particular, states with relevant 1p-3h configuration with respect to the 16O core are mainly populated by the reaction (18O, 17O) while states with known 2p-4h configuration are excited by the (18O, 16O) one. Exact Finite Range Coupled Reaction Channel calculations based on a parameter free double-folding optical potential were performed to reproduce the measured absolute cross-section angular distributions. The (18O, 16O) is found to be an important probe to study pair configurations in nuclear states. [ABSTRACT FROM AUTHOR]

The 120Sn(p, t) 118Sn reaction was investigated at 35 MeV incident energy. The 118Sn excitation energy spectrum was reconstructed up to about 16 MeV. Preliminary results show the presence of a broad resonance at high excitation energy, compatible with the predicted population of the Giant Pairing Vibration (GPV). [ABSTRACT FROM AUTHOR]

Recently, a rainbow pattern in the elastic scattering of 16O+ 27Al at Elab. = 100MeV was reported. In the present paper, we show that the predicted change of slope of the cross section, as a function of angle, is mostly due to the far-side component of the scattering, which is affected by the inelastic couplings. The experimental data is consistent with the calculations up to the infeection point, where the effect of the couplings is significant. New experimental data, in very good agreement with the theoretical expectations around the Coulomb rainbow angle, are also presented. [ABSTRACT FROM AUTHOR]

This Letter reports a study of the highly debated 10Li structure through the d(9Li, p)10Li one-neutron transfer reaction at 100 MeV. The 10Li energy spectrum is measured up to 4.6 MeV and angular distributions corresponding to different excitation energy regions are reported for the first time. The comparison between data and theoretical predictions, including pairing correlation effects, shows the existence of a p1/2 resonance at 0.45 ± 0.03 MeV excitation energy, while no evidence for a significant s-wave contribution close to the threshold energy is observed. Moreover, two high-lying structures are populated at 1.5 and 2.9 MeV. The corresponding angular distributions suggest a significant s1/2 partial-wave contribution for the 1.5 MeV structure and a mixing of configurations at higher energy, with the d5/2 partial-wave contributing the most to the cross section. [ABSTRACT FROM AUTHOR]

Aging of human skeletal muscles is associated with increased passive stiffness, but it is still debated whether muscle fibers or extracellular matrix (ECM) are the determinants of such change. To answer this question, we compared the passive stress generated by elongation of fibers alone and arranged in small bundles in young healthy (Y: 21 years) and elderly (E: 67 years) subjects. The physiological range of sarcomere length (SL) 2.5-3.3 μm was explored. The area of ECM between muscle fibers was determined on transversal sections with picrosirius red, a staining specific for collagen fibers. The passive tension of fiber bundles was significantly higher in E compared to Y at all SL. However, the resistance to elongation of fibers alone was not different between the two groups, while the ECM contribution was significantly increased in E compared to Y. The proportion of muscle area occupied by ECM increased from 3.3% in Y to 8.2% in E. When the contribution of ECM to bundle tension was normalized to the fraction of area occupied by ECM, the difference disappeared. We conclude that, in human skeletal muscles, the age-related reduced compliance is due to an increased stiffness of ECM, mainly caused by collagen accumulation.

This Letter reports a study of the highly debated ^{10}Li structure through the d(^{9}Li,p)^{10}Li one-neutron transfer reaction at 100 MeV. The ^{10}Li energy spectrum is measured up to 4.6 MeV and angular distributions corresponding to different excitation energy regions are reported for the first time. The comparison between data and theoretical predictions, including pairing correlation effects, shows the existence of a p_{1/2} resonance at 0.45±0.03  MeV excitation energy, while no evidence for a significant s-wave contribution close to the threshold energy is observed. Moreover, two high-lying structures are populated at 1.5 and 2.9 MeV. The corresponding angular distributions suggest a significant s_{1/2} partial-wave contribution for the 1.5 MeV structure and a mixing of configurations at higher energy, with the d_{5/2} partial-wave contributing the most to the cross section.

Asthma needs continuous treatment often for years. In humans, some drugs are administered via aerosol, therefore they come in contact with both respiratory and olfactory mucosa. We explored the possibility that antiasthma corticosteroid treatment could influence the olfactory function by passage through the nose. A group of mice was exposed twice daily for 42 days to fluticasone propionate aerosol and was compared with a control group. Olfactory behavior, respiratory mechanics, histology, and immunoreactivity in the olfactory system were assessed. Fluticasone-treated mice were slower in retrieving a piece of hidden food, but both groups were similarly fast when the food was visible. When a clearly detectable odor was present in the environment, all mice behaved in a similar way. Respiratory mechanics indices were similar in all mice except for the viscose resistance, which was reduced in fluticasone-treated mice. Olfactory mucosa of fluticasone-treated mice was thicker than that of controls. Slight but consistent differences in staining were present for Olfactory Marker Protein but not for other proteins. A mild impairment of olfactory function is present in mice chronically treated with fluticasone aerosol, apparently accompanied by slight modifications of the olfactory receptor cells, and suggests monitoring of olfactory function modifications in long-term steroid users.

Olfactory bulbectomy in rodents causes behavioral alterations, which result in a model of depression, validated for pharmacological screening of antidepressant drugs. To unravel the appearance and time course of the major behavioral effects which follow surgery, mice underwent olfactory bulb ablation or sham operation, and were analyzed after 1, 2, or 4 weeks. Bulbectomized (BX) mice were anosmic, and hyperactive when tested under stressful situations in the forced swimming test. Predatory aggression was upregulated in a time-dependent way: only after 4 weeks BX mice were faster than controls in attacking prey. At the same time, they were less aggressive against intruders; they did not differ from controls in open field exploration, but displayed a cognitive impairment in water maze. Behavioral tests thus indicated a marked hyperreactivity, a dissociation among different aggressive behaviors, and also a cognitive impairment induced by bulbectomy. Histological confirmation of the damage revealed that major modifications took place in the rostral pole of frontal lobes, with a significant increase in the width of the rostral migratory stream, 2 weeks after surgery, and in the subventricular zone, 4 weeks after surgery. These results suggest a base for the time-course of appearance of behavioral symptoms in BX mice.

In order to design new ligands for protein-binding sites of unknown structure, it would be useful to predict the likely sites of hydrogen bonding of an unknown protein fragment to a known molecule. The positions of maxima and minima in the electrostatic potential at appropriate distances from the van der Waals surface were calculated for various small molecules, nucleic acid bases, peptide units and amino acid side chains containing groups which can form the biologically important N-H...O=C and N-H...N hydrogen bonds. Their ability to predict the positions of H and O/N in hydrogen bonded complexes, as predicted by optimising the electrostatic interactions of pairs of such molecules constrained by the molecular shapes, was assessed. It is shown that extrema in the electrostatic potential around the isolated molecules give worthwhile predictions for the locations of hydrogen binding partners. For molecules bound by a single N-H...O=C hydrogen bond, the electrostatic maximum associated with the H is usually less than 1 A from an acceptor atom, while a C=O electrostatic minimum is generally less than 1.5 A from the hydrogen bond proton. However, a significant number of hydrogen bonds form to the opposite lone pair from the electrostatic minimum, in which case the separation is up to 3.3 A. This reflects the broad electrostatic potential well around a carbonyl oxygen between the lone pair directions. The model predicts when neighbouring atoms drastically change the hydrogen bonding characteristics of an N-H or C=O group. Although the geometries of hydrogen bonded complexes are influenced by the other van der Waals contacts between the molecules, particularly multiple hydrogen bonds, these influences are constant when considering hydrogen bonding to a specific uncharacterised binding site. Hence, the consideration of sterically accessible electrostatic extrema will be useful in the design of new ligands.