Landscape construction and time reckoning in Iron Age Celtic Iberia

In this paper, we report on three areas of the Iberian Peninsula that were occupied at least during the Iron Age and the early stages of Romanisation, where observations of astronomical phenomena in the landscape, rock carvings, and Latin inscriptions point to a particular method of time reckoning. All of these sites have previously been connected with the Celtic culture. The knowledge of the natural world that Classical sources assigned to these peoples need not have been reflected in a monolithic calendrical system used by all Celtic communities on the Continent. In fact, such a ‘Celtic calendar’ may have had different expressions in different areas, expressed in different ways, although sharing some common characteristics such as the particual use of the lunar and solar cycles.V članku poročamo o treh območjih na Iberskem polotoku, ki so bila poseljena vsaj od železne dobe in začetka romanizacije, kjer smo na podlagi opazovanj astronomskih fenomenov v pokrajini, na podlagi skalnih rezbarij in latinskih napisov prepoznali posebno metodo merjenja časa. Vsa predstavljena najdišča so bila doslej povezana s keltsko kulturo. Znanje o naravi in svetu, ki so ga klasični viri pripisali Keltom, se ni nujno odražalo v monolitskem koledarskem sistemu, ki so ga uporabljale vse keltske skupnosti na celini. Takšen ‘keltski koledar’ se je lahko v različnih območjih izražal na drugačne načine, vendar je pri tem ohranil nekatere skupne značilnosti, kot je npr. posebna uporaba Luninih in Sončevih ciklov

Tissue distribution of mercury and its relationship with selenium in atlantic bluefin tuna (Thunnus thynnus l.)

Mercury (Hg) is an important heavy metal to consider in marine predators, while selenium (Se) has a natural antagonistic effect on this metal in fish. The Atlantic bluefin tuna (ABFT, Thunnus thynnus) is a pelagic top-level predator of the trophic web and their Hg muscular content is an object of concern in food safety. Nevertheless, little is known about levels of this metal in remaining tissues, which may be important as by-product source, and its relationship with Se. Thus, concentration of both elements in liver, kidney, brain, gill and bone, in addition to muscle, of ABFT were determined. The kidney was the tissue with the highest concentration of Hg (Total-Hg, THg) and Se, and the Se/THg concentration ratio was similar in all tissues, except bone and muscle. The Selenium Health Benefit Value (HBVSe ) was positive in each specimen and tissue, indicating that the Se plays an important role against Hg not only in the muscle. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Preprin

Thracian dolmens and their orientations

The volumen title is ASTRONOMY AND COSMOLOGY IN FOLK TRADITIONS AND CULTURAL HERITAGE Edited by Jonas Vaigkunas. Archaeologia Baltica volume 10 was prepared by Klaipėda University Institute of Baltic Sea Region History and Archaeology and Museum of Molėtai district. Published with a grant from the Ministry of Education and Science of The Republic of Lithuania.[EN]Spread over south-eastern Bulgaria, northern Greece and the European part of Turkey are a large number of megalithic tombs. These dolmens were built from around the twelfth century BC to about the sixth century BC. The monuments were built with well cut slabs, defining a rectangular space with a roof. A small hole marks the entrance. A dromos is also present in some dolmens and all of these structures used to be covered by a tumulus. We present the first results from a series of campaigns devoted to measuring the orientation of these structures. The first campaign was carried out in the Strandja Mountains where 31 dolmens (among other monuments) were measured. The dolmens are not orientated at random, and a particular pattem of orientation has been found for the entrance of these monuments. Several tentative explanations are attempted and supported with information provided by contemporary Greek sources.This work is partially financed under the framework of the projects P310793 `Arqueoastronomia' of the Instituto de Astrofísica de Canarias and AYA2004-01010 `Orientatio ad Sidera' of the Spanish Ministry of Education and Science.Peer reviewe

Foreword by Guest Editors MAA 2018 Volume 18 Issue 4

MAA SPECIAL ISSUE VOL 18 ISSUE 4: Sixty-three (63) Selected (peer reviewed) Papers of the INSAP X – Oxford XI – SEAC 25th Joint Conference ‘ROAD TO THE STARS’, held in Santiago de Compostela, Spain, 18th–22nd September 2017 Mediterranean Archaeology and Archaeometry (MAA) is an Open Access Journal published since 2001 by The University of the Aegean, Department of Mediterranean Studies, Rhodes, Greece. It covers the dual nature of archaeology and cultural heritage with science which includes, amongst others, natural science applied to archaeology (physics, chemistry, biology, geology, geophysics, astronomy), archaeology, ancient history, cultural sustainability, astronomy in culture, physical anthropology, digital heritage, new archaeological finds reports, historical archaeology, architectural archaeology, ethnoarchaeological prospective, critical reviews, from Paleolithic to medieval/Byzantine eras, all pertinent to the Mediterranean including adjacent areas with due interaction and/or parallel comparison to ancient Mediterranean cultures

Effects of Frequency Dependence of the External Quantum Efficiency of Perovskite Solar Cells

Perovskite solar cells are known to show very long response time scales, on the order of milliseconds to seconds. This generates considerable doubt over the validity of the measured external quantum efficiency (EQE) and consequently the estimation of the short-circuit current density. We observe a variation as high as 10% in the values of the EQE of perovskite solar cells for different optical chopper frequencies between 10 and 500 Hz, indicating a need to establish well-defined protocols of EQE measurement. We also corroborate these values and obtain new insights regarding the working mechanisms of perovskite solar cells from intensity-modulated photocurrent spectroscopy measurements, identifying the evolution of the EQE over a range of frequencies, displaying a singular reduction at very low frequencies. This reduction in EQE is ascribed to additional resistive contributions hindering charge extraction in the perovskite solar cell at short-circuit conditions, which are delayed because of the concomitant large low-frequency capacitance

Symbiotic Solitons in Heteronuclear Multicomponent Bose-Einstein condensates

We show that bright solitons exist in quasi-one dimensional heteronuclear multicomponent Bose-Einstein condensates with repulsive self-interaction and attractive inter-species interaction. They are remarkably robust to perturbations of initial data and collisions and can be generated by the mechanism of modulational instability. Some possibilities for control and the behavior of the system in three dimensions are also discussed

Calendrical Deer, Time-Reckoning and landscape in Iron-Age North-West Spain

The volumen title is ASTRONOMY AND COSMOLOGY IN FOLK TRADITIONS AND CULTURAL HERITAGE Edited by Jonas Vaigkunas. Archaeologia Baltica volume 10 was prepared by Klaipėda University Institute of Baltic Sea Region History and Archaeology and Museum of Molėtai district. Published with a grant from the Ministry of Education and Science of The Republic of Lithuania.[EN]The relationship between petroglyphs and archaeoastronomy has been treated in several ways in the past. In the present study we examine a particular motif found among the rock carvings in the north-west of the Iberian Peninsula: a large deer with over-sized horns and an unnatural number of tips on each horn. A multidisciplinary approach combining landscape archaeology, comparative history of religions, and archaeoastronomy suggests a coherent interpretation of the motif. It reveals a unique amalgamation of calendrical motives, landscape relationships and lunisolar events. It may also be significant in relation to the Celtic world-view and its artistic manifestation, and to the relationship between time and landscape.This work is partially financed under the framework of projects P310793 `Arqueoastronomia' of the Instituto de Astrofísica de Canarias, AYA2004-01010 `Orientatio ad Sidera' of the Spanish Ministry of Education and Science, and project PGIDITO6PXIB236147PR `Arqueología e relixión no noroeste peninsular' of the Xunta de Galicia.Peer reviewe

Impedance spectroscopy characterisation of highly efficient silicon solar cells under different light illumination intensities

Highly efficient silicon solar cells have been characterised by impedance spectroscopy and current–potential characteristic in the dark and with different illumination intensities. For each illumination the impedance behaviour has been analysed at different applied bias potentials, in the forward and reverse region, comparing the results with the current–potential characteristic. Different cell parameters, as series and parallel resistances, capacitance, diode factor, minority carrier lifetime, acceptor impurities density and depletion layer charge density have been obtained as a function of bias voltage for different light illumination intensities. The effect of light-generated carriers and applied bias in the behaviour of the solar cell under illumination is discusse