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Parafunctional masticatory activity, such as the tooth clenching and grinding that is associated with bruxism, is encountered by clinicians in many disciplines, including dentistry, neurology and psychiatry. Despite this, little is known about the neurological basis for these activities. To identify the brain network engaged in such complex oromotor activity, functional magnetic resonance imaging (fMRI) was used to elucidate the brain activation patterns of 20 individuals (10 males and 10 females, mean ± s.d. age of 26·3 ± 4·1 years) with (parafunctional, PFx group, 5M/5F) and without (normal functional, NFx group, 5 M/5F) self-reported parafunctional grinding and clenching habits during clenching and grinding tasks. Subject group classification was based on: (i) self-reported history, (ii) clinical examination, (iii) evaluation of dental casts and (iv) positive responses to the temporomandibular disorder (TMD) History Questionnaire [Dworkin and LeResche, Journal of Craniomandibular Disorders, (1992) 6:301]. While subjects performed these oromotor tasks, each wore a custom-designed oral appliance minimizing head motion during imaging. Mean per cent signal changes showed significant between group differences in motor cortical (supplementary motor area, sensorimotor cortex and rolandic operculum) and subcortical (caudate) regions. Supplementary motor area data suggest that motor planning and initiation, particularly during the act of clenching, are less prominent in individuals with oromotor parafunctional behaviours. The overall extent of activated areas was reduced in subjects with self-reported parafunctional masticatory activity compared with the controls. This study’s methodology and findings provide an initial step in understanding the neurological basis of parafunctional masticatory activities that are relevant for therapeutic research applications of temporomandibular joint and muscle disorders and associated comorbidities. [ABSTRACT FROM AUTHOR]

With the DISTO spectrometer, exclusive η production in pp collisions have been measured at kinetic energies of Tbeam=2.15, 2.50 and 2.85 GeV, respectively, via the π+π-π0 decay channel. The resulting angular distributions of the η are important for the interpretation of dilepton spectra obtained in elementary as well as heavy ion reactions. [ABSTRACT FROM AUTHOR]

BACKGROUND: The mesocorticolimbic dopamine system is implicated in motivation and reward and may be involved in the development of alcoholism. METHODS: We used functional magnetic resonance imaging to study the blood oxygen level-dependent (BOLD) response to alcohol-related olfactory stimuli (AROS; odors of beer and whiskey) and non-alcohol-related olfactory stimuli (NAROS; odors of grass and leather) in 10 high-risk (HR) drinkers (average drinks per week, 19.99; SD, 6.99; all with > or = 2 first- or second-degree alcoholic relatives) and 5 low-risk (LR) social drinking controls (drinks per week, 2.82; SD, 2.87; 1 subject had 1 second-degree alcoholic relative). Data were analyzed with SPM99 and random effects analysis by using regions of interest and corrected cluster statistics (p < 0.05) to focus on the nucleus accumbens (NAc) and ventral tegmental area (VTA). RESULTS: In HR subjects, there was a greater BOLD signal increase in the NAc during AROS than during clean air. BOLD signal increases during AROS were also greater in the NAc than the signal increases induced by NAROS. The AROS signal was significantly greater than the NAROS signal in a small number of voxels in the VTA. Finally, the AROS/NAROS difference signal was larger in HR drinkers in both the NAc and VTA. CONCLUSIONS: Alcoholic olfactory cues may invoke the dopaminergic mesocorticolimbic system to a greater degree than nonalcoholic odors and could be effective tools in exploring the role of the dopamine system in susceptibility to alcoholism. [ABSTRACT FROM AUTHOR]

Angular distributions for the exclusive reaction pp → ppη observed via the π+ π-π0 decay channel have been measured at Tbeam 2.15 GeV, 2.50 GeV and 2.85 GeV (excess energies Q 324 MeV, 412 MeV and 554 MeV). The polar angle of the η shows an anisotropy with respect to the beam direction for the lowest energy, which vanishes for the higher energies. The anisotropy of the pp polar angle increases slightly with the beam energy. [ABSTRACT FROM AUTHOR]

Presents information on the data acquisition system/magnetic spectrometer built by the DISTO collaboration. What the system was designed to do; Basing of the system on a single VME crate; Elements which the system is made up of; Structure of the system.

Describes a fully programmable trigger circuit which was built for the DISTO experiment at Saturne. Construction of a magnetic spectrometer by the DISTO collaboration; Overview of the 1st level trigger of the circuit.

Measures the stored proton beam polarization time dependence in an induced depolarized resonance. Role of magnetic field oscillation along the beam axis; Variation of resonance distance by changing oscillating field frequency.