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Generation-IV sodium fast reactors (SFR) will only become acceptable and accepted if they can safely prevent or accommodate reactivity insertion accidents that could lead to the release of large quantities of mechanical energy, in excess of the reactor containment's capacity. The CADOR approach based on reinforced Doppler reactivity feedback is shown to be an attractive means of effectively preventing such reactivity insertion accidents. The accrued Doppler feedback is achieved by combining two effects: (i) introducing a neutron moderator material in the core so as to soften the neutron spectrum; and (ii) lowering the fuel temperature in nominal conditions so as to increase the margin to fuel melting. This study shows that, by applying this CADOR approach to a Generation-IV oxide-fuelled SFR, the resulting core can be made inherently resistant to reactivity insertion accidents, while also having increased resistance to loss-of-coolant accidents. These preliminary results have to be confirmed and completed to meet multiple safety objectives. In particular, some margin gains have to be found to guarantee against the risk of sodium boiling during unprotected loss of supply power accidents. The main drawback of the CADOR concept is a drastically reduced core power density compared to conventional designs. This has a large impact on core size and other parameters.

This study presents a new method to estimate 3-D linear accelerations at tibial and femoral functional coordinate systems. The method combines the use of 3-D accelerometers, 3-D gyroscopes and reflective markers rigidly fixed on an exoskeleton and, a functional postural calibration method. Marker positions were tracked by a six-camera optoelectronic system (VICON 460, Oxford Metrics). The purpose of this study was to determine if this method could discriminate between medial osteoarthritic and asymptomatic knees during gait. Nine patients with osteoarthritic knees and nine asymptomatic control subjects were included in this study. Eighteen parameters representing maximal, minimal, and range of acceleration values were extracted during the loading and preswing to mid-swing phase periods, and were compared in both groups. Results show good discriminative capacity of the new method. Eight parameters were significantly different between both groups. The proposed method has the potential to be used in comprehending and monitoring gait strategy in patients with osteoarthritic knee. Index Terms--Accelerometer and gyroscope, biomechanics, exoskeleton, gait analysis, internal and external accelerations, knee osteoarthritis (OA).

The man operon that codes the components of the phosphoenolpyruvate:mannose phosphotransferase system (PTS) in Streptococcus salivarius is described. This system is responsible for the transport of glucose and mannose.

The phosphotransferase system proteins IIIHMan and IIILMan of Streptococcus salivarius were biochemically and functionally characterized through partial purification by gel filtration and ion-exchange chromatography and through separation by two-dimensional gel electrophoresis. The results showed that the two varieties of IIIMan have two phosphorylation sites, one of which is heat resistant, while the other is heat-labile. The phosphorylation on two histidine residues was confirmed through comparison of the N-terminal amino acid sequences with the N-terminal sequence of IIA domains of the mannose family.

This paper presents a new method to automatically synthesize robot compliant motions based on hybrid impedance control. The scheme relies on decoupled linear impedance models of the robot and the environment, in which the errors due to control, task frame estimation, as well as environment uncertainty are explicitly taken into account. The technique consists of selecting appropriate manipulator impedances to match the environment dynamics and satisfy all the task goals. Two experimental examples of this methodology are presented.

Forty strains of Streptococcus and other bacteria were tested for the presence of proteins IIIHMan and IIILMan that appear to control sugar metabolism. The strains were tested using analysis of PEP-dependent phosphoproteins, Western blot analysis, and PEP-dependent 2DG phosphorylation by antibodies. IIIHMan and IIILMan are believed to regulate the phosphoenolpyruvate:sugar phosphotransferase system. Only Streptococcus salivarius and S. vestibularis possess both proteins.

Compliant control of robot manipulators in environments with unknown or variable dynamics is a broad area of research which has many unresolved problems. Due to the dynamic coupling between the robot and the environment in the constrained directions, hybrid control schemes seem best suited to perform the control since they can be tuned independently in each direction. The directional adaptive damping control scheme is an example of a hybrid control scheme that automatically determines the direction of the constraint and adapts the force response according to the surface stiffness. The extension of this scheme to the more general case where there are more than one constraint surfaces cannot be done easily because the estimation of the constraint's orientations is much harder in this case. Furthermore, if the constraints change abruptly, unwanted transients will be created because of the control mode switching. The use of reasoning with approximate or partial models of the environment appears to offer a solution to these problems.