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The morphology, as well as the related fracture and mechanical behavior of vinyl ester resins (DVER) of different molecular weights cured with styrene (S) and modified with two different liquid rubbers are presented and discussed. The liquid rubbers are: carboxyl terminated poly(butadiene-co-acrylonitrile) (CTBN), a common toughening agent for epoxy resins, and an almost unreactive rubber with the DVER and S comonomers, and a reactive rubber (vinyl terminated poly(butadiene-co-acrylonitrile), (VTBN). The initial miscibility of the modified systems and the reactivity of the rubber determine the final morphology of the material. This morphology will correspond to a continuous main phase (rich in the DVER-S copolymer) with simple rubber rich inclusions (as in the epoxy-rubber systems) or with inclusions with a complex internal structure, where phase separation occurs as in the low profile modified unsaturated polyester resins. The morphologies developed are strongly dependent on the resin molecular weight as well as on the elastomer added. In spite of the initially higher compatibility of the S-DVER-CTBN system with respect to the S-DVER-VTBN system, the reactivity of the vinyl-ended elastomer leads to a much finer distribution of the elastomeric phase. In particular, the low molecular weight resin cured with S and modified with 10% of CTBN leads to a cocontinuous structure with microvoids that generates a material of low density and poor mechanical and fracture properties. On the other hand, the use of VTBN as additive leads to a more compact morphology, with gradual reduction of the mechanical performance of the modified resins and improved fracture behavior.

In a recent paper, it was described how semi-insulating (SI) liquid encapsulated Czochralski (LEC) gallium arsenide particle detectors made by Alenia SpA have been tested and found to be understandable in terms of one function: the local charge collection efficiency. We have now measured, always within the context of the RD8 experiment, the local charge collection efficiency for these diodes using a technique called OBIC (optical beam induced current) and derived the active region width ( W ) as a function of bias in a range of values lower than those obtainable with particles. Using data both from OBIC and from the previous paper, W is found to behave approximately linearly as a function of bias larger than about 50 V. Below this value, W follows a square root law as a function of bias.

A reduced-complexity MAP equalizer (RMAP) is proposed, together with an associate channel estimator, where only H channel states having largest probability are adaptively retained over the total of N states, with H/spl Lt/N. For a channel length L, RMAP reduces the complexity from LN to LH. Channel estimator complexity is LH/sup 2/ + HL/sup 2/ instead of LN/sup 2/. Performance analysis shows that P-MAP allows practical applications using state-of-art low-cost DSP devices: this is the case of a HF digital modem recently developed at Marconi Mobile laboratories.

Gallium arsenide particle detectors made by Alenia SpA have been tested within the context of the RD-8 project and found to have a high charge-collection efficiency (75%). We have analysed the data and found the overall behaviour of these detectors to be coherent and understandable in terms of one function: the local charge-collection efficiency. Two ways have been used to measure the width of the active region and the increase of such a width as a function of bias is found not to be consistent with a simple square-root law.

Few studies have addressed the cardiovascular risk factors in the context of family aggregates. This study focused on the assessment of cardiovascular risk factors in seven father-mother-son groups. Although the sample size precludes any generalizations beyond this sample, patterns of risk factors among the fathers, mothers, and sons suggest direction for future research in this area.

The presented study showed the relationship between dopamine receptor gene polymorphism and personality traits in athletes training in martial arts. Behavioral modulation resulting from a balance of the neurotransmitters dopamine and norepinephrine to inactivation of the dorsolateral prefrontal cortex and dysregulation of various pathways involved in attention and impulse control processes; Methods: The study was conducted among martial arts athletes. The study group included 258 volunteers and 284 controls. The genetic test was performed using the real-time PCR method; psychological tests were performed using standardized TCI questionnaires. All analyses were performed using STATISTICA 13. Results: Interaction between martial arts and DRD2 rs1799732 (manual) G/-(VIC/FAM)-ins/del and RD- Harm avoidance and Reward Dependence scale were demonstrated. In athletes, a lower Reward Dependence scale score was associated with the DRD2 rs1799732 (manual)-/-polymorphism compared to the control group. Conclusions: It seems justified to study not only genetic aspects related to brain transmission dopamine in martial arts athletes. In the studied athletes, the features related to reward addiction and harm avoidance are particularly important in connection with the dopaminergic reward system in the brain