Carotenoid-based sexual traits are thought to be reliable indicators of male quality because they might be scarce and therefore might indicate the ability of males to gather high-quality food and because they are involved in important physiological functions (as immune enhancers and antioxidants). We performed an experiment where male and female zebra finches (Taeniopygia guttata) were provided with increasing carotenoid doses in the drinking water during 4 weeks (bill color of this species is a carotenoid-based sexual signal). Simultaneously, birds were split into two groups: one receiving weekly injections of Escherichia coli lipopolysaccharide in order to activate the immune system, the other being injected with the same volume of phosphate buffered saline. We assessed how carotenoid availability and immune activation affected the amount of circulating plasma carotenoids, the beak color, and the antioxidant defenses (assessed as the resistance of red blood cells to a controlled free radical attack). Carotenoid availability affected the amount of circulating carotenoids and beak color; both variables reached a plateau at the highest carotenoid doses. Immune activation diverted carotenoids from plasma, and this in turn affected the expression of the sexual trait. Finally, we found a positive correlation between the change in circulating carotenoids and antioxidant defenses. These results support the idea that carotenoids have important physiological properties that ensure the honesty of carotenoid-based sexual traits.

We report on 11 patients (nine unrelated and a brother pair) with severe haemophilia A and factor VIII (FVIII) inhibitor, in whom immune tolerance (IIT) was induced with recombinant FVIII (r-FVIII). Their age ranged from 11 months to 47 years. The number of exposure days (ED) at inhibitor detection varied from 11 to 130. Nine of the 11 patients were high responders ¿>10 Bethesda units (BU) with peak inhibitor levels ranging from 10 to 566 BU. The other two were low responders with peak levels between 0.7 and 2 BU. Before inhibitor detection, the patients had been receiving products of various purities. The IIT regimens were very heterogeneous, and the treatment schedule varied from a short period with 50 IU kg-1 every 2 days, followed by 100 IU kg-1 every 2 days and then 220 IU kg-1 daily. The outcome was considered successful when the inhibitor level fell to 0.6 BU or lower after IIT treatment. The outcome overall was successful in nine out of 11 patients (81.8%), with the nine successful cases comprising seven of the nine high responders (77.8%) and the two low responders. Definite failure of IIT was observed in one high responder after two different IIT regimens. A second high responder is still on IIT treatment. All patients in whom IIT was successful are currently receiving r-FVIII on demand or prophylactically at various dosages. Despite the variability of the patient characteristics and the IIT schedules, this study demonstrates that r-FVIII represents an effective alternative for the eradication of inhibitors through IIT.

20Functional neuronal correlations between pairs of neurons are thought to play an important role 21 in neuronal information processing and optimal neuronal computations during attention, 22 perception, decision-making and learning. These noise correlations are often assumed to be 23 stable in time. However, recent studies suggest that cognitive processes are rhythmic, this 24 rhythmicity accounting for variations in overt behavioral performance. Whether this 25 rhythmicity coincides with variations in shared noise variability is unknown. Here, we perform 26 simultaneous recordings from the macaque frontal eye fields, while animals are engaged in a 27 spatial memory task. We report that noise correlations in prefrontal cortex fluctuate 28 rhythmically in the high alpha (10-16Hz) and beta (20-30Hz) frequency ranges. Importantly, 29 these rhythmic modulations in shared neuronal variability account for dynamic changes in overt 30 behavioral performance. They also coincide with increased spike-LFP phase coupling in these 31 specific frequency ranges, the spatial profile of which vary between superficial and deep 32 cortical layers. Finally, we demonstrate, using an artificial neuronal model, that rhythmic 33 variations in noise correlation oscillations parsimoniously arise from long range (LFP) and local 34 spike-LFP phase coupling mechanisms. Thus a significant portion of noise correlation 35 fluctuations can be attributed to long-range global network rhythmicity. 36 37 65 rhythmic modulations in noise correlations account both for overt behavioral performance and 66 for layer specific modulations in spike-field phase coupling. Based on an artificial model, we 67 demonstrate that rhythmic variations in noise correlation oscillations parsimoniously arise from 68 long range (LFP) and local spike-LFP phase coupling mechanisms. 69 70 4 Results 71Neuronal recordings were performed in the prefrontal cortex, specifically in the frontal 72 eye field (FEF, figure 1A), a structure known to play a key role in covert spatial attention 28,33-73 35 . In each session, multi-unit activity (MUA) and local field potential (LFP) were recorded 74 bilaterally, while monkeys performed a memory guided saccade task ( figure 1B). Specifically, 75 monkeys were required to hold the position of a spatial cue in memory for 700 to 1900ms and 76 to perform a saccade towards the memorized spatial location on the extinction of the fixation 77 point that served as a go signal. In the following, noise correlations between the different 78 prefrontal signals of the same hemisphere were computed during the time interval running from 79 300ms to 1500ms following cue offset, on neuronal activities averaged over 200ms sliding 80 windows (step of 10ms). As shown by previous studies, noise correlations decrease as a 81 function of cortical distance ( Figure S1A, 1-way ANOVA, p<0.001, Wilcoxon rank sum test, 82 p<0.001 for 750 µm, p<0.001 for 1000 µm, 23,36,37 and are significantly lower among neuronal 83 pairs with different spatial selectivity than neu...

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Parametric excitation walking is one of methods to realize dynamic walking on a level ground. This method has first applied to a biped robot with telescopic legs and later to a robot with actuated knee joints. In parametric excitation walking, mechanical energy is increased by periodic up-and-down motion of the center of mass. While parametric excitation walking with telescopic legs has verified by an experimental robot, that with actuated knees has not yet as far as we know. The purpose of this paper is to present demonstration experiment of parametric excitation walking with a kneed biped robot. To do this, we develop an experimental kneed biped robot having four parallel legs with semicircular feet. In the experiment, the robot achieves walking on a level ground more than 15 steps. We also measure the movements of the robot during walking by a 3D motion capture and compare with simulation results.