72 research outputs found
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SODAR DATA FROM OYSTER BAY AT WINYAH BAY NATIONAL ESTUARINE RESEARCH RESERVE
The SecondWind TritonÂŽ is a SODAR (SOnic Detection And Ranging) sonic wind profiler (TritonÂŽ sodar) system capable of profiling the wind characteristics up to 200m above the instrument. SODAR systems transmit acoustic chirps into the atmosphere and measure the backscattered signal returned to the device. The primary source of acoustic scattering is variations in air temperature, which cause changes in the refractive index of sound. By measuring the Dopplerâshifted frequency of these returned signals, the TritonÂŽ can calculate the windâs speed and direction for the volume of air above the instrument, measured at ten fixed heights, known as station heights. The TritonÂŽ is specifically designed for the purpose of wind energy resource assessment as it can remotely capture wind data at heights above ground where wind turbine rotors operate. The measurements made include horizontal wind speed and direction, vertical wind speed, and turbulence. Other integrated sensors provide time and location via GPS, barometric pressure, humidity, and the tilt of the instrument. The study area is located east of Georgetown, South Carolina in North Inlet â Winyah Bay National Estuarine Research Reserve. The monitoring period for data in this report begins 5/14/2009 9:30:00 AM EST and ends 8/2/2010 11:40:00 AM EST
Wool sheep and purple snails - Longâterm continuity of animal exploitation in ancient Meninx (Jerba/Tunisia)
Archaeological research at the ancient city of Meninx in Jerba, Tunisia, carried out by the Institut National du Patrimoine Tunisie and Ludwig Maximilian University of Munich (LMU) produced more than 10,000 faunal specimens and shed light on subsistence activities spanning from the fourth century BCE until the seventh century CE. Despite its highly diverse fauna totalling at least 69 species of mammals, birds, reptiles, fish and molluscs, domestic livestock formed the mainstay of the economy at Meninx. Throughout site occupation and compared with contemporaneous sites in coastal Tunisia and Libya, sheep were of prime importance at Meninx. Diachronic demographic profiling illustrates an emphasis on the production of wool for making textiles. Together with the ubiquitous presence of crushed banded dyeâmurex (Hexaplex trunculus) shells implying exploitation of purple dyes, we assume that both activities were integrated into a single chaĂŽne opĂŠratoire for making purpleâdyed fabrics that were traded across the Mediterranean from Punic until Late Roman times. Zooarchaeological findings also suggest that during the Byzantine Period, this major economic activity came to a standstill, with people returning to more selfâsufficient subsistence strategies. An intersite comparison furthermore revealed that high proportions of ovicaprines are a typical feature of PunicâRoman sites in Jerba. But even at the height of Roman power in the region, autochthonous husbandry traditions continued to exist on the island, as illustrated by the fauna from Henchir Bourgou
Typing Late Prehistoric Cows and BullsâOsteology and Genetics of Cattle at the Eketorp Ringfort on the Ăland Island in Sweden
Human management of livestock and the presence of different breeds have been discussed in archaeozoology and animal breeding. Traditionally osteometrics has been the main tool in addressing these questions. We combine osteometrics with molecular sex identifications of 104 of 340 morphometrically analysed bones in order to investigate the use of cattle at the Eketorp ringfort on the Ăland island in Sweden. The fort is dated to 300â1220/50 A.D., revealing three different building phases. In order to investigate specific patterns and shifts through time in the use of cattle the genetic data is evaluated in relation to osteometric patterns and occurrence of pathologies on cattle metapodia. Males were genotyped for a Y-chromosomal SNP in UTY19 that separates the two major haplogroups, Y1 and Y2, in taurine cattle. A subset of the samples were also genotyped for one SNP involved in coat coloration (MC1R), one SNP putatively involved in resistance to cattle plague (TLR4), and one SNP in intron 5 of the IGF-1 gene that has been associated to size and reproduction
The Origins of Lactase Persistence in Europe
Lactase persistence (LP) is common among people of European ancestry, but with the exception of some African, Middle Eastern and southern Asian groups, is rare or absent elsewhere in the world. Lactase gene haplotype conservation around a polymorphism strongly associated with LP in Europeans (â13,910 C/T) indicates that the derived allele is recent in origin and has been subject to strong positive selection. Furthermore, ancient DNA work has shown that the â13,910*T (derived) allele was very rare or absent in early Neolithic central Europeans. It is unlikely that LP would provide a selective advantage without a supply of fresh milk, and this has lead to a gene-culture coevolutionary model where lactase persistence is only favoured in cultures practicing dairying, and dairying is more favoured in lactase persistent populations. We have developed a flexible demic computer simulation model to explore the spread of lactase persistence, dairying, other subsistence practices and unlinked genetic markers in Europe and western Asia's geographic space. Using data on â13,910*T allele frequency and farming arrival dates across Europe, and approximate Bayesian computation to estimate parameters of interest, we infer that the â13,910*T allele first underwent selection among dairying farmers around 7,500 years ago in a region between the central Balkans and central Europe, possibly in association with the dissemination of the Neolithic Linearbandkeramik culture over Central Europe. Furthermore, our results suggest that natural selection favouring a lactase persistence allele was not higher in northern latitudes through an increased requirement for dietary vitamin D. Our results provide a coherent and spatially explicit picture of the coevolution of lactase persistence and dairying in Europe
Unravelling the complexity of domestication:A case study using morphometrics and ancient DNA analyses of archaeological pigs from Romania
Funding statement. This work was supported by the Natural Environment Research Council (NE/F003382/1) and the Leverhulme Trust (F/00 128/AX) Acknowledgements. Archaeozoological analyses conducted by A. BaËlaËs¸escu were supported by three grants from the Romanian National Authority for Scientific Research, CNCS UEFISCDI (PN-II-RU-TE-20113-0146, PN-II-ID-PCE-2011-3-0982 and PN-IIID-PCE-2011-3-1015). We thank the archeologists CaËtaËlin Bem, Alexandru Dragoman, Valentin Dumitras¸cu, Laura Dietrich, Raluca KogaËlniceanu, Cristian Micu, StaËnica Pandrea, Valentin Parnic, George Trohani, Valentina Voinea for the material they generously provided. We thank the many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¨r Naturkunde, Berlin; Muse´um National dâHistoire Naturelle, Paris; Muse´um dâHistoire Naturelle, Gene`ve; Museum fu¨r Haustierkunde, Halle; National Museum of Natural History, Washington; The Field Museum, Chicago and The American Museum of Natural History, New York; The Naturhistorisches Museum, BernPeer reviewedPublisher PD
SODAR DATA FROM OYSTER BAY AT WINYAH BAY NATIONAL ESTUARINE RESEARCH RESERVE
The SecondWind TritonÂŽ is a SODAR (SOnic Detection And Ranging) sonic wind profiler (TritonÂŽ sodar) system capable of profiling the wind characteristics up to 200m above the instrument. SODAR systems transmit acoustic chirps into the atmosphere and measure the backscattered signal returned to the device. The primary source of acoustic scattering is variations in air temperature, which cause changes in the refractive index of sound. By measuring the Dopplerâshifted frequency of these returned signals, the TritonÂŽ can calculate the windâs speed and direction for the volume of air above the instrument, measured at ten fixed heights, known as station heights. The TritonÂŽ is specifically designed for the purpose of wind energy resource assessment as it can remotely capture wind data at heights above ground where wind turbine rotors operate. The measurements made include horizontal wind speed and direction, vertical wind speed, and turbulence. Other integrated sensors provide time and location via GPS, barometric pressure, humidity, and the tilt of the instrument. The study area is located east of Georgetown, South Carolina in North Inlet â Winyah Bay National Estuarine Research Reserve. The monitoring period for data in this report begins 5/14/2009 9:30:00 AM EST and ends 8/2/2010 11:40:00 AM EST
Characterization of bidirectional impulse turbines for thermoacoustic engines
A bidirectional impulse turbine to convert thermoacoustic power into electricity is investigated. Experimental measurements are done with a loudspeaker for varying acoustic conditions and turbine loads. The results are used to characterize the turbine performance and compare it to steady flow turbomachinery and turbines in oscillating water columns. A dimensional analysis is done to identify the variables that influence the turbine performance, after which a scaling is determined that uniquely determines the efficiency of the turbine. The work is finished by providing the impedance of the bidirectional turbine such that it can be implemented in a thermoacoustic engine
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