Abstract. We present millimeter-wave maps of the L 1157 bipolar outflow in several molecular emission lines. The CO emission traces the bulk of the outflowing gas in the red and blue shifted lobes displaying a remarkable Sshaped symmetry indicating the presence of a precessing jet. We determine the physical characteristics of the CO flow and show evidence for 3 or 4 independent episodes of mass ejection from the source. Molecules such as C3H2, N2H+ and DCO + are seen to be abundant only in the quiescent medium, and result to be the best tracers of the high-density core surrounding the driving source of the outflow. Other molecules (SiO, CH3OH, H2CO, HCN, CN, SO, SO2) are abundant in the outflow lobes, but exhibit strong emission gradients. Multiline observations of some species indicate that these gradients are not simply due to excitation effects, but are caused by an actual stratification in the chemical composition of the shocked molecular gas. Shock tracers such as SiO, CH3OH, and sulphur-bearing molecules result to be the most promising candidates as potential chemical clocks to study the evolution of outflows. The characteristics of the L 1157 outflow, when compared to those of other outflows from Class 0 sources, indicate that L 1157 is the prototype of a category of bipolar outflows around Class 0 protostars which we denominate "chemically active outflows".

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Abstract. Archaeological excavations carried out at Turó del Calvari (Tarragona, Spain) have revealed a protohistoric building interpreted as one of the earliest enclosures of power operating during the Early Iron Age in the northeast of the Iberian Peninsula. The structure is exceptional in several respects: the techniques of construction, the materials used, and the topographic situation. The building is perfectly integrated in the landscape and has an exquisite geometrical design, with measurement units based on the Iberian foot. The intended beauty in having used the golden ratio in its construction and an orientation that is both stellar and solar demonstrates the existence at that time of a complete series of mechanisms of representation and territorial control. This was based on the use of rituals and feasts as elements of political cohesion by an emergent elite within a process that reproduced a scaled-down Mediterranean cultural system in an indigenous space.

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Abstract. Chemical studies have a great potential to study the structure and evolution of the bipolar molecular outflows driven by young stellar objects. In this paper, we discuss some very recent mm-wave studies of L 1157, a bipolar molecular outflow driven by a Class 0 protostar. These observations are very useful to illustrate the chemical alterations produced by a violent highly-collimated outflow. Different molecular lines are observed to trace different components of the gas. Some molecules are abundant in the quiescent medium but are not observed in the shock (e.g. C3H2, ^H" 1 ", H 13 CO + , DCO + ), whereas some otherwise rare molecules are very enhanced at the shocked region (e.g. SiO, CH 3 OH, H 2 CO, HCN, CN, SO, S0 2 ). In addition, we have observed strong gradients in the chemical composition across the outflow blue lobe. We briefly discuss the chemistry of the most important molecules, devoting special attention to the species which are thought to be abundant in interstellar ice mantles.