58 research outputs found
Site assessment of Douglas Shoal ship grounding in the Great Barrier Reef
The bulk carrier Shen Neng 1 ran aground on Douglas Shoal in the Great Barrier Reef Marine Park in April 2010. At over 40 hectares, this is the largest ship grounding scar known in the Great Barrier Reef, and possibly the largest reef-related grounding in the world. Challenges for assessment of the site included its large scale and the remote nature of Douglas Shoal coupled with its high exposure to wind, wave conditions and fauna that may pose safety hazards. Marine surveys used multiple and novel methods including sediment sampling combined with visual and acoustic survey techniques
Sloan Digital Sky Survey IV: mapping the Milky Way, nearby galaxies, and the distant universe
We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median ). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July
Sloan Digital Sky Survey IV: mapping the Milky Way, nearby galaxies, and the distant universe
We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median ). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July
Marine and fresh-water molluscs from the Epipaleolithic site of Hayonim Terrace, Western Galilee, Northern Israel, and other East Mediterranean sites
The marine and fresh-water shells from the Geometric Kebaran A to Late Natufian (ca. 13.000-10500 B.P.) site of Hayonim Terrace are analysed by species. All shells (mainly dentalia) were probably used as ornementals; none are food debris. The sample is compared with other pre-Bronze Age East Mediterranean shell collections.Les mollusques marins et d'eau douce du Kébarien géométrique A au Natoufien récent (ca. 13.000-10.500 B.P.) provenant de la Terrasse de Hayonim sont analysés ici par espèces. Tous les coquillages (surtout les dentales) étaient probablement utilisés comme ornements. On a comparé cet échantillon aux collections de Méditerranée orientale à l'Age du Bronze.Reese David S. Marine and fresh-water molluscs from the Epipaleolithic site of Hayonim Terrace, Western Galilee, Northern Israel, and other East Mediterranean sites. In: Paléorient, 1982, vol. 8, n°2. pp. 83-90
Cranial evidence for the presence of a second endemic elephant species on Cyprus
Cyprus, the largest Eastern Mediterranean island, hosted a highly impoverished endemic mammalian fauna during the Pleistocene to early Holocene times. This was a result of its extreme biogeographic isolation since its formation, which prevented the immigration of most terrestrial mammals, except for those with apparent sea channel crossing abilities. The main faunal elements are the extremely dwarfed hippo Phanourios minor, commonly found in many sites across the island, and the dwarf elephant Palaeoloxodon cypriotes. The latter is a very small-sized elephant species, comparable in size with the Siculo-Maltese Palaeoloxodon falconeri. Larger dental specimens found sporadically during the last century, raised the possibility that a second endemic elephant, larger than P. cypriotes, may have also existed in Cyprus. Here we describe a skull recently excavated in the coastal area of Xylophágou, SE Cyprus, which provides evidence that, indeed, two elephant species have existed on the island. The larger species, Palaeoloxodon xylophagou n. sp., is still strongly dwarfed and characterised by elongated, low and wide skull, diverging tusk alveoli and comparatively large molars. Dimensionally the dentition is distinctly larger than P. cypriotes and close to Palaeoloxodon tiliensis, though the skull size is intermediate between P. tiliensis and P. falconeri. Both Cypriot elephant species exhibit morphological affinities with Palaeoloxodon antiquus, which is their probable ancestor. Stratigraphic data suggest that P. xylophagou is older (late Middle Pleistocene), while P. cypriotes is more recent (latest Pleistocene to early Holocene) and may have descended from the former or - less probably - evolved as a result of a separate, more recent colonisation event. © 2015 Elsevier Ltd and INQUA
Ancient DNA forces reconsideration of evolutionary history of Mediterranean pygmy elephantids
During the Pleistocene pygmy elephantids, some only a quarter of their ancestors' size, were present on Mediterranean islands until about 10 000 years ago (y.a.). Using a new methodology for ancient DNA (aDNA) studies, the whole genomic multiple displacement amplification method, we were able to retrieve cytochrome b (cytb) DNA fragments from 4200 to 800 000 y.a. specimens from island and mainland samples, including pygmy and normal-sized forms. The short DNA sequence (43 bp) retrieved from the 800 000 y.a. sample is one of the oldest DNA fragment ever retrieved. Duplication of the experiments in two laboratories, the occurrence of three diagnostic sites and the results of the phylogenetic analyses strongly support its authenticity. Our results challenge the prevailing view that pygmy elephantids of the eastern Mediterranean originated exclusively from Elephas, suggesting independent histories of dwarfism and the presence of both pygmy mammoths and elephant-like taxa on these islands. Based on our molecular data, the origin of the Tilos and Cyprus elephantids from a lineage within the genus Elephas is confirmed, while the DNA sequence from the Cretan sample falls clearly within the mammoth clade. Thus, the name Mammuthus creticus rather than Elephas creticus, seems to be justified for this form. Our findings also suggest a need to re-evaluate the evolutionary history of the Sicilian/Maltese species, traditionally included in the genus Elephas
Plasticity and damage with gradient enhancement: A review of application to high speed forming
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