Squaring the circle. Social and environmental implications of pre-pottery neolithic building technology at Tell Qarassa (South Syria)

We present the results of the microstratigraphic, phytolith and wood charcoal study of the remains of a 10.5 ka roof. The roof is part of a building excavated at Tell Qarassa (South Syria), assigned to the Pre-Pottery Neolithic B period (PPNB). The Pre-Pottery Neolithic (PPN) period in the Levant coincides with the emergence of farming. This fundamental change in subsistence strategy implied the shift from mobile to settled aggregated life, and from tents and huts to hard buildings. As settled life spread across the Levant, a generalised transition from round to square buildings occurred, that is a trademark of the PPNB period. The study of these buildings is fundamental for the understanding of the ever-stronger reciprocal socio-ecological relationship humans developed with the local environment since the introduction of sedentism and domestication. Descriptions of buildings in PPN archaeological contexts are usually restricted to the macroscopic observation of wooden elements (posts and beams) and mineral components (daub, plaster and stone elements). Reconstructions of microscopic and organic components are frequently based on ethnographic analogy. The direct study of macroscopic and microscopic, organic and mineral, building components performed at Tell Qarassa provides new insights on building conception, maintenance, use and destruction. These elements reflect new emerging paradigms in the relationship between Neolithic societies and the environment. A square building was possibly covered here with a radial roof, providing a glance into a topologic shift in the conception and understanding of volumes, from round-based to square-based geometries. Macroscopic and microscopic roof components indicate buildings were conceived for year-round residence rather than seasonal mobility. This implied performing maintenance and restoration of partially damaged buildings, as well as their adaptation to seasonal variability

Frame presentations: variants of the reals, rings of functions, their Dedekind completions, and the unit circle

176 p.

[A_Elvillar_Hechicera] Documentación geométrica del dolmen de la Chabola de la Hechicera (Elvillar, Álava)

[ES] Tumba megalítica compuesta por 17 losas de gran tamaño, incluida la tapa. La estructura ocupa un espacio de 10 x 4 metros en planta, unos 4 metros de altura en la cámara. Conserva restos del túmulo que forma aproximadamente un círculo de unos 10 metros de radio.

Goierriko garraioaren hobekuntza eta ingurumen inpaktua

[EU]Goierriko eskualdean egun batean burutzen diren bidai guztien %9a bakarrik burutzen da garraio publiko bidez. Hau gertatzearen bizilagunen “aitzakia” nagusia honakoa da: zerbitzua oso txarra da. Niri ordea, ondorengo zalantza datorkit burura: nahiz eta zerbitzua hobea izan, garraio publikoa gehiago erabiliko litzateke? Hau biraka dabilen gurpil zoroa da. Zerbitzua txarra delako ez dabil jende gehiago, baina ez du merezi zerbitzua hobetzea jende gutxi ibiltzen delako. Guzti hau argitzearren eta Goierriko garraio publikoaren hobekuntza sustatzeko zer egin daitekeen aztertzeko garatu da lan hau. Hobekuntza termino hau autobus gehiago jartzearekin erlazionatzen dugu gehienetan, baina nik beste planteamendu bat eman nahi izan diot. Bidaiari gutxi daudenez, ezin dira maiztasun handiz autobusak ezarri, proiektua ez baita bideragarria. Horregatik dagoen zerbitzua, gutxi bada ere, bizilagunei erabat moldatua egotea mahaigaineratu nahi izan dut, bizilagun hauen sentsibilizazioari arreta berezia eskainiz.

Uptake and intracytoplasmic storage of pigmented particles by human CD34+stromal cells/telocytes: endocytic property of telocytes

We studied the phagocytic-like capacity of human CD34+ stromal cells/telocytes (TCs). For this, we examined segments of the colon after injection of India ink to help surgeons localize lesions identified at endoscopy. Our results demonstrate that CD34+ TCs have endocytic properties (phagocytic-like TCs: phTCs), with the capacity to uptake and store India ink particles. phTCs conserve the characteristics of TCs (long, thin, bipolar or multipolar, moniliform cytoplasmic processes/telopodes, with linear distribution of the pigment) and maintain their typical distribution. Likewise, they are easily distinguished from pigment-loaded macrophages (CD68+ macrophages, with oval morphology and coarse granules of pigment clustered in their cytoplasm). A few c-kit/CD117+ interstitial cells of Cajal also incorporate pigment and may conserve the phagocytic-like property of their probable TC precursors. CD34+ stromal cells in other locations (skin and periodontal tissues) also have the phagocytic-like capacity to uptake and store pigments (hemosiderin, some components of dental amalgam and melanin). This suggests a function of TCs in general, which may be related to the transfer of macromolecules in these cells. Our ultrastructural observation of melanin-storing stromal cells with characteristics of TCs (telopodes with dichotomous branching pattern) favours this possibility. In conclusion, intestinal TCs have a phagocytic-like property, a function that may be generalized to TCs in other locations. This function (the ability to internalize small particles), together with the capacity of these cells to release extracellular vesicles with macromolecules, could close the cellular bidirectional cooperative circle of informative exchange and intercellular interactions.

Self-Similarity and helical symmetry in vortex generator flow simulations

According to experimental observations, the vortices generated by vortex generators have previously been observed to be self-similar for both the axial (u(z)) and azimuthal (u(circle minus)) velocity profiles. Further, the measured vortices have been observed to obey the criteria for helical symmetry. This is a powerful result, since it reduces the highly complex flow to merely four parameters. In the present work, corresponding computer simulations using Reynolds-Averaged Navier-Stokes equations have been carried out and compared to the experimental observations. The main objective of this study is to investigate how well the simulations can reproduce the physics of the flow and if the same analytical model can be applied. Using this model, parametric studies can be significantly reduced and, further, reliable simulations can substantially reduce the costs of the parametric studies themselves.