The current biomechanical interpretation of the chimpanzee's bipedal walking argues that larger lateral and vertical displacements of the body center of mass occur in the chimpanzee's "side-to-side" gait than in the human striding gait. The evolutionary hypothesis underlying this study is the following: during the evolution of human bipedalism one of the necessary changes could have been the progressive reduction of these displacements of the body center of mass. In order to quantitatively test this hypothesis, it is necessary to obtain simultaneously the trajectories of the centers of mass of the whole body and of the different body parts. To solve this problem, a new method of three-dimensional analysis of walking, associated with a volumetric modelling of the body, has been developed based on finite-element modeling. An orthogonal synchrophotographic device yielding four synchronous pictures of the walking subject allows a qualitative analysis of the photographic sequences together with the results of their quantitative analysis. This method was applied to an adult man, a 3-year-old girl and a 9-year-old male chimpanzee. Our results suggest that the trajectory of the body center of mass of the human is distinguished from that of the chimpanzee not by a lower movement amplitude but by the synchronization of the transverse and vertical displacements into two periodic curves in phase with one another. The non-human primate uses its repertoire of arboreal movements in its bipedal terrestrial gait, provisionally referred to as a "rope-walker" gait. We show that the interpretation of a "side-to-side" gait is not applicable to the chimpanzee. We argue that similarly this interpretation and the initial hypothesis presuppose a basic symmetric structure of the gait, in relation to the sagittal plane of progression, similar to the human one. This lateral symmetry of the right and left displacements of the center of gravity, in phase with the right and left single supports of walking, is probably a very derived feature of the human gait. We suggest that low lateral and vertical displacements of the body center of mass are not indicative of a progressive bipedal gait and we discuss the new evolutionary implications of our results.

The port-miou river, close to Cassis, in the Provence (France) is the unique subterranean and sub marine river which has been dammed with the objective of collecting fresh water. The river present a section of almost 22 m wide and 18 m high, between −21 and −3 m asl. The construction of the dam has been stepped in two phases: the first one in 1971 was a chicane dam with unique aim of preventing sea water to penetrate towards the upstream of the karst by flowing at the bottom of the conduct whilst the fresh water flows at the upper part of the conduct toward the see. The chicane dam allowed passing the floods of the subterranean river without changing the water head in the karstic conduct. The most important is the measure of the discharge with several methods to cross checks the values of the measures. The measures of salinity at various levels were also made continuously to exhibit the correlation between discharge and salinity. In parallel another submarine karstic river close to Cassis, the Bestouan River, was explored and analyzed with the same aim of collecting fresh water. The subject of the proposed paper is to present this unique experience with the team which did the job from the very beginning to the present day. IntroductionIn coastal areas, vast quantities of water flow through the underground water bearing strata finally getting lost in the sea. These submarine outflows are for the most part fresh water, but occasionally they are briny. The most common and most spectacular are found in karstic limestone formations. The karstic underground rivers of Port Miou and Bestouan, close to the city of Cassis in the Provence, France, are typical and have been. They are known for centuries. In

The Young's modulus of roller compacted concrete is rarely measured. However, it has a direct influence on the dam behavior and especially for static loads during earthquakes. In many cases, static and dynamic calculations are done with modules copied from other study. This dam was studied using in situ module measurements that contribute to a choice of the type of dam and the choice and the choice of materials from borrow pits near the dam.

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