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Nanosecond scale molecular dynamics simulations of the behavior of the one-dimensional water molecule chains adsorbed in the parallel nanochannels of bikitaite, a rare lithium containing zeolite, were performed at different temperatures and for the fully and partially hydrated material. New empirical potential functions have been developed for representing lithium-water interactions. The structure and the vibrational spectrum of bikitaite were in agreement both with experimental data and Car-Parrinello molecular dynamics results. Classical molecular dynamics simulations were extended to the nanosecond time scale in order to study the flip motion of water molecules around the hydrogen bonds connecting adjacent molecules in the chains, which has been observed by NMR experiments, and the dehydration mechanism at high temperature. Computed relaxation times of the flip motion follow the Arrhenius behavior found experimentally, but the activation energy of the simulated system is slightly underestimated. Based on the results of the simulations, it may be suggested that the dehydration proceeds by a defect-driven stepwise diffusion. The diffusive mechanism appears as a single-file motion: the molecules never pass one another, even at temperatures as high as about 1000 K, nor can they switch between different channels. However, the mean square displacement (MSD) of the molecules, computed with respect to the center of mass of the simulated system, shows an irregular trend from which the single-file diffusion cannot be clearly evidenced. If the MSDs are evaluated with respect to the center of mass of the molecules hosted in each channel, the expected dependence on the square root of time finally appears.

In the present study, the susceptibility of knockout interleukin-6 (IL-6(-/-)) mice to various convulsant stimuli has been evaluated and compared with other three related mice strains. Animals were treated with chemical convulsants impairing the gamma-aminobutyric acid neurotransmission [pentylenetetrazole (PTZ), picrotoxin, bicuculline, methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM), methyl-beta-carboline-3-carboxylate (beta-CCM)], enhancing glutamatergic neurotransmission [N-methyl-d-aspartate (NMDA), alpha-amino-3 hydroxy-5-methyl-4-isoxazolepropionate (AMPA) and kainic acid (KA)] or a K(+)channel blocker [4-aminopyridine (4-AP)]. The behavioural changes of such convulsant stimuli on IL-6(-/-) were observed and compared with those observed in C57, IL-6(+/+) and DBA/2 mice. The occurrence of clonic and/or tonic seizures was scored and statistically analysed to observe possible differences on seizure susceptibility. The IL-6(-/-) mice exhibited significantly higher seizure susceptibility to PTZ, beta-CCM, DMCM, NMDA, AMPA and KA than did the other mice strains, with the exception of DBA/2 mice. This study demonstrates that IL-6(-/-) mice possess an increased susceptibility to some convulsant stimuli. In particular, the major convulsant effects produced by NMDA, AMPA and KA suggest that the excitatory amino acid system is more active in the central nervous system (CNS) of IL-6(-/-) mice. The present data suggest that IL-6(-/-) mice might be a valid novel epileptic model for the study of pathophysiology and pharmacology of epileptic seizures.

Mobbing constitutes a phenomenon not yet clearly defined. The activity, located in the II Faculty of Medicine and Surgery, is specifically dedicated to such phenomenon, which is the outcome of cooperation. The examined population is composed by a light prevalence of men (51.3%) respect to women (48.6%), aged around 42 years and employees (71.6%), workers (28.4%). All patients have been submitted to working anamnesis before being subjected to a psychiatric examination and psycodiagnostic tests. The emerged data underline a trouble of adaptation 55.4% of the cases, 40.5% is affected by psychiatric pathologies, 4.1% of the patients do not show mental disorders. A certification of compatibility with mobbing has been possible to be verified in 49% of the cases. Nevertheless, it is necessary a connection between a physician and business medical service. We hope a necessary enactment of a specific regulation.

Mobbing constitutes a phenomenon not yet clearly defined. The activity, located in the H Faculty of Medicine and Surgery, is specifically dedicated to such phenomenon, which is the outcome of cooperation. The examined population is composed by a light prevalence of women (54%) respect to men (46%), aged around 44 years and employees (73%), workers (27%). All patients have been submitted to working anamnesis before being subjected to a psychiatric examination and psycodiagnostic tests. The emerged data underline a trouble of adaptation 63% of the cases (to which we have released a certification of compatibility with mobbing), 28% is affected by psychiatric pathologies, 9% of the patients do not show mental disorders. Nevertheless, it is necessary a connection between a physician and business medical service.

And' is studied the noise exposure (with the calculation of the Lep,d) and the auditory function (with the method MPB 2002) in employed to the coffee's workmanship. The purpose was double. To deepen aspects a little studied thin to today and to compare the results with the "values limit of exposure" and the "values of exposure that make to go off the action" foreseen by the European directive 2003 of February 6th 2003. The data have underlined levels of noise below the inferior values of exposure that make to go off the action (80 dBAs) and absence of auditory effects from noise. The results suggest therefore the opportunity to extend the observations in other similar technological cycles, also to appraise other risks reported in literature as the cutaneous and respiratory allergies.

The physiological disposition of a new steroid anti-inflammatory agent, deflazacort, was examined in rat, dog and man following 5 mg/kg doses to the animals, and 50 mg to humans. The administered radiocarbon [2'-14C]-deflazacort), is rapidly and extensively absorbed into the general circulation in rat and man, whereas the bioavailability in the dog is low. The terminal plasma half-life for radioactivity elimination was, on the average, 11, 15 and 28 hr in rats, dogs and man, respectively. Urinary excretion was the predominant route of 14C elimination in the rat (-54% of the dose) and in man (-68% of the dose), whereas in the dog the majority of the dose was eliminated via the feces (82%). Tissue distribution studies in the rat did not show target organs, with the exception of the blood cells. Studies of binding to plasma proteins of the 21-desacetyl deflazacort, demonstrate in all the species a rather low level of binding of non-saturable type.