77 research outputs found

    Elaia, Pergamon's maritime satellite:The rise and fall of an ancient harbour city shaped by shoreline migration

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    Throughout human history, communication and trade have been key to society. Because maritime trade facilitated the rapid transportation of passengers and freight at relatively low cost, harbours became hubs for traffic, trade and exchange. This general statement holds true for the Pergamenian kingdom, which ruled wide parts of today's western Turkey during Hellenistic times. Its harbour, located at the city of Elaia on the eastern Aegean shore, was used extensively for commercial and military purposes. This study reconstructs the coastal evolution in and around the ancient harbour of Elaia and compares the observed environmental modifications with archaeological and historical findings. We use micropalaeontological, sedimentological and geochemical proxies to reconstruct the palaeoenvironmental dynamics and evolution of the ancient harbour. The geoarchaeological results confirm the archaeological and historical evidence for Elaia's primacy during Hellenistic and early Roman times, and the city's gradual decline during the late Roman period. Furthermore, our study demonstrates that Elaia holds a unique position as a harbour city during ancient times in the eastern Aegean region, because it was not greatly influenced by the high sediment supply associated with river deltas. Consequently, no dredging of the harbour basins is documented, creating exceptional geo-bioarchives for palaeoenvironmental reconstructions

    Anti-malarial activity of Holarrhena antidysenterica and Viola canescens, plants traditionally used against malaria in the Garhwal region of north-west Himalaya

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    <p>Abstract</p> <p>Background</p> <p>The increasing number of multidrug-resistant <it>Plasmodium </it>strains warrants exploration of new anti-malarials. Medicinal plant research has become more important, particularly after the development of Chinese anti-malarial drug artemisnin from <it>Artemisia annua</it>. The present study shows evaluation of anti-malarial effects of two plants commonly used against malaria in the Garhwal region of north-west Himalaya, in order to discover the herbal-based medicine.</p> <p>Methods</p> <p><it>In vitro </it>anti-plasmodial sensitivity of plant extracts was assessed using schizont maturation and parasite lactate dehydrogenase (pLDH) assay. Cytotoxic activities of the examined extracts were determined on L-6 cells of rat skeletal muscle myoblast. The 4-day test for anti-malarial activity against a chloroquine sensitive <it>Plasmodium berghei </it>NK65 strain in Swiss albino mice was used for monitoring <it>in vivo </it>activity of plant extracts.</p> <p>Results</p> <p>Chloroform extract of <it>H. antidysenterica </it>(HA-2) and petroleum ether extract of <it>V. canescens </it>(VC-1) plants significantly reduced parasitaemia in <it>P. berghei </it>infected mice. The extract HA-2 showed <it>in vitro </it>anti-plasmodial activity with its IC<sub>50 </sub>value 5.5 μg/ml using pLDH assay and ED<sub>50 </sub>value 18.29 mg/kg in <it>P. berghei </it>infected Swiss albino mice. Similarly petroleum ether extract of <it>V. canescens </it>(VC-1) showed <it>in vitro </it>anti-plasmodial activity with its IC<sub>50 </sub>value 2.76 μg/ml using pLDH assay and ED<sub>50 </sub>15.8 mg/kg in <it>P. berghei </it>infected mice. The extracts coded as HA-2 at 30 mg/kg and VC-1 at 20 mg/kg exhibited parasite inhibition in mice: 73.2% and 63.0% respectively. Of these two plant extracts, petroleum ether extract of <it>V. canescens </it>was found slightly cytotoxic.</p> <p>Conclusion</p> <p>The present investigation reflects the use of these traditional medicinal plants against malaria and these plants may work as potential source in the development of variety of herbal formulations for the treatment of malaria.</p

    Elsevier's Encyclopædia of organic chemistry /

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    Supplements to v. 14 issued 1951-69 (8 v.)Vol. 12 B ed. by F Radt.Called Series III, Carboisocyclic condensed compounds. Series I and II, vol. 1-11, Series IV, vols. 15-18, and General indexes, vols. 19 and 20, not published.v. 12A. Bycyclic compounds (except Naphthalene).--v. 12B. Naphthalene. 9 v.--v. 13. Trycyclic compounds.--v. 14. Tetra- and higher-cyclic compounds.Mode of access: Internet

    Directional Stability and Control During Landing Rollout

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    The Yığma Tepe of Pergamon: Internal construction of a monumental burial mound from shear wave reflection sounding and wavefield modelling

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    The Yığma Tepe of Pergamon is one of the largest known burial mounds in the Eastern Mediterranean. Its internal structure, especially the existence and location of burials, remains unknown so far because its height of 32 m and the diameter of 158 m have restricted extensive excavations. To explore the interior of the Yığma Tepe, we applied shear wave reflection profiling and traveltime tomography, locally complemented by electrical resistivity tomography. Shear wave reflection imaging enabled us to identify the layering and localize structures down to the basal surface of the mound with a metre‐scale resolution. A grid of crossing SH‐wave profiles with 4‐m line spacing covered the central mound area. The Yığma Tepe can be subdivided into three stratigraphic layers representing different construction phases, each about 10 m thick. The deepest is a consolidated layer with a locally compacted surface. SH‐wave reflection imaging verified the collapsed remains of a tunnel system and a shaft at about 30‐m depth that had been dug into the mound at the level of the basal surface at the beginning of the 20th century. The tunnel collapse created a damage zone of decreased S‐wave velocity reaching up to the overlying middle layer, in which four seismic objects of interest (SOIs) were detected. The largest of these SOIs is a north–south‐oriented structure, about 15 m long and 4 m wide. SH‐viscoelastic forward modelling showed that it likely consists of a collapsed walled cavity with a zone of loosened soil above. The third layer covers the underlying two and is enriched with large stone packages as verified by local excavations. We show the capabilities of shear‐wave reflection seismic to image small‐scale structures under complicated topographic conditions and how characteristics of cavities and volumes of decompacted soil can be evaluated by wavefield modelling.Agence nationale de la recherche (ANR) http://dx.doi.org/10.13039/501100001665Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659German Archaeological Institut (DAI

    Analysis and simulation of nonlinear handling characteristics of automotive vehicles with focus on lateral load transfer

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    This paper mainly investigates steady-state nonlinear cornering behaviour of vehicles under lateral load transfer. A normal load dependent nonlinear cornering stiffness is utilised instead of the constant one to reflect the effect of normal load fluctuations. Thus, the relationship between the nonlinear cornering stiffness, tyre property coefficients, roll stiffness ratio and lateral load transfer has been formulated. A clear and simple criterion has been proposed to demonstrate how the handling behaviour is changed in the high lateral acceleration region. This criterion indicates that the nonlinear handling behaviour is dependent on the car's roll stiffness ratio, static margin, tyre cornering stiffness and tyre property, coefficients. It may be considered as one of many advantageous criteria in motor vehicle design
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