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  • 1
    Publication Date: 2015-05-01
    Description: We present results from 13 cosmological simulations that explore the parameter space of the ‘Evolution and Assembly of GaLaxies and their Environments’ (EAGLE) simulation project. Four of the simulations follow the evolution of a periodic cube L  = 50 cMpc on a side, and each employs a different subgrid model of the energetic feedback associated with star formation. The relevant parameters were adjusted so that the simulations each reproduce the observed galaxy stellar mass function at z  = 0.1. Three of the simulations fail to form disc galaxies as extended as observed, and we show analytically that this is a consequence of numerical radiative losses that reduce the efficiency of stellar feedback in high-density gas. Such losses are greatly reduced in the fourth simulation – the EAGLE reference model – by injecting more energy in higher density gas. This model produces galaxies with the observed size distribution, and also reproduces many galaxy scaling relations. In the remaining nine simulations, a single parameter or process of the reference model was varied at a time. We find that the properties of galaxies with stellar mass   M * (the ‘knee’ of the galaxy stellar mass function) are largely governed by feedback associated with star formation, while those of more massive galaxies are also controlled by feedback from accretion on to their central black holes. Both processes must be efficient in order to reproduce the observed galaxy population. In general, simulations that have been calibrated to reproduce the low-redshift galaxy stellar mass function will still not form realistic galaxies, but the additional requirement that galaxy sizes be acceptable leads to agreement with a large range of observables.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
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  • 2
    Publication Date: 2015-05-24
    Description: We investigate the evolution of galaxy masses and star formation rates in the Evolution and Assembly of Galaxies and their Environment ( eagle ) simulations. These comprise a suite of hydrodynamical simulations in a cold dark matter cosmogony with subgrid models for radiative cooling, star formation, stellar mass-loss and feedback from stars and accreting black holes. The subgrid feedback was calibrated to reproduce the observed present-day galaxy stellar mass function and galaxy sizes. Here, we demonstrate that the simulations reproduce the observed growth of the stellar mass density to within 20 per cent. The simulations also track the observed evolution of the galaxy stellar mass function out to redshift z  = 7, with differences comparable to the plausible uncertainties in the interpretation of the data. Just as with observed galaxies, the specific star formation rates of simulated galaxies are bimodal, with distinct star forming and passive sequences. The specific star formation rates of star-forming galaxies are typically 0.2 to 0.5 dex lower than observed, but the evolution of the rates track the observations closely. The unprecedented level of agreement between simulation and data across cosmic time makes eagle a powerful resource to understand the physical processes that govern galaxy formation.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
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  • 3
    Publication Date: 2019
    Description: Recycled aggregates (RA) from construction and demolition can be used in permeable concretes (PC), improving the environment. PCs have a significant porous network, their cement paste and the interaction between the paste and the RA establishing their strength. Therefore, it is important to evaluate the porosity in the interfacial transition zones. The porosity of the cement paste, the aggregate and the interfacial transitional zones (ITZ) of a PC with recycled coarse aggregates (RCA) and silica fume (SF) is measured by means of image analysis–scanning electron microscope (IA)-(SEM) and by mapping the chemical elements with an SEM-EDS (energy dispersive spectrometer) detector microanalysis linked to the SEM and, as a contrast, the mercury intrusion porosimetry technique (MIP). In the IA process, a “mask” was created for the aggregate and another for the paste, which determined the porosity percentage (for the anhydrous material and the products of hydration). The results showed that using SF caused a reduction (32%) in the cement paste porosity in comparison with the PC with RA. The use of RA in the PC led to a significant increase (190%) in the porosity at different thicknesses of ITZ compared with the reference PC. Finally, the MIP study shows that the use of SF caused a decrease in the micropores, mesopores and macropores.
    Electronic ISSN: 1996-1944
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Published by MDPI
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  • 4
    Publication Date: 2014-11-14
    Description: We introduce the Virgo Consortium's Evolution and Assembly of GaLaxies and their Environments (EAGLE) project, a suite of hydrodynamical simulations that follow the formation of galaxies and supermassive black holes in cosmologically representative volumes of a standard cold dark matter universe. We discuss the limitations of such simulations in light of their finite resolution and poorly constrained subgrid physics, and how these affect their predictive power. One major improvement is our treatment of feedback from massive stars and active galactic nuclei (AGN) in which thermal energy is injected into the gas without the need to turn off cooling or decouple hydrodynamical forces, allowing winds to develop without predetermined speed or mass loading factors. Because the feedback efficiencies cannot be predicted from first principles, we calibrate them to the present-day galaxy stellar mass function and the amplitude of the galaxy-central black hole mass relation, also taking galaxy sizes into account. The observed galaxy stellar mass function is reproduced to 0.2 dex over the full resolved mass range, 10 8 〈 M * /M 10 11 , a level of agreement close to that attained by semi-analytic models, and unprecedented for hydrodynamical simulations. We compare our results to a representative set of low-redshift observables not considered in the calibration, and find good agreement with the observed galaxy specific star formation rates, passive fractions, Tully–Fisher relation, total stellar luminosities of galaxy clusters, and column density distributions of intergalactic C iv and O vi . While the mass–metallicity relations for gas and stars are consistent with observations for M * 10 9 M ( M * 10 10 M at intermediate resolution), they are insufficiently steep at lower masses. For the reference model, the gas fractions and temperatures are too high for clusters of galaxies, but for galaxy groups these discrepancies can be resolved by adopting a higher heating temperature in the subgrid prescription for AGN feedback. The EAGLE simulation suite, which also includes physics variations and higher resolution zoomed-in volumes described elsewhere, constitutes a valuable new resource for studies of galaxy formation.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
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  • 5
    Publication Date: 2008-03-28
    Description: The earliest hominin occupation of Europe is one of the most debated topics in palaeoanthropology. However, the purportedly oldest of the Early Pleistocene sites in Eurasia lack precise age control and contain stone tools rather than human fossil remains. Here we report the discovery of a human mandible associated with an assemblage of Mode 1 lithic tools and faunal remains bearing traces of hominin processing, in stratigraphic level TE9 at the site of the Sima del Elefante, Atapuerca, Spain. Level TE9 has been dated to the Early Pleistocene (approximately 1.2-1.1 Myr), based on a combination of palaeomagnetism, cosmogenic nuclides and biostratigraphy. The Sima del Elefante site thus emerges as the oldest, most accurately dated record of human occupation in Europe, to our knowledge. The study of the human mandible suggests that the first settlement of Western Europe could be related to an early demographic expansion out of Africa. The new evidence, with previous findings in other Atapuerca sites (level TD6 from Gran Dolina), also suggests that a speciation event occurred in this extreme area of the Eurasian continent during the Early Pleistocene, initiating the hominin lineage represented by the TE9 and TD6 hominins.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Carbonell, Eudald -- Bermudez de Castro, Jose M -- Pares, Josep M -- Perez-Gonzalez, Alfredo -- Cuenca-Bescos, Gloria -- Olle, Andreu -- Mosquera, Marina -- Huguet, Rosa -- van der Made, Jan -- Rosas, Antonio -- Sala, Robert -- Vallverdu, Josep -- Garcia, Nuria -- Granger, Darryl E -- Martinon-Torres, Maria -- Rodriguez, Xose P -- Stock, Greg M -- Verges, Josep M -- Allue, Ethel -- Burjachs, Francesc -- Caceres, Isabel -- Canals, Antoni -- Benito, Alfonso -- Diez, Carlos -- Lozano, Marina -- Mateos, Ana -- Navazo, Marta -- Rodriguez, Jesus -- Rosell, Jordi -- Arsuaga, Juan L -- England -- Nature. 2008 Mar 27;452(7186):465-9. doi: 10.1038/nature06815.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institut Catala de Paleoecologia Humana i Evolucio Social, Area de Prehistoria, Universitat Rovira i Virgili, Placa Imperial Tarraco 1, 43005 Tarragona, Spain. eudald.carbonell@urv.cat〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18368116" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Fossils ; Genetic Speciation ; Geologic Sediments ; History, Ancient ; Hominidae/anatomy & histology/*classification ; Mammals/anatomy & histology ; *Mandible/anatomy & histology ; Spain ; Technology
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 6
    Publication Date: 2007-10-27
    Description: The melanocortin 1 receptor (MC1R) regulates pigmentation in humans and other vertebrates. Variants of MC1R with reduced function are associated with pale skin color and red hair in humans of primarily European origin. We amplified and sequenced a fragment of the MC1R gene (mc1r) from two Neanderthal remains. Both specimens have a mutation that was not found in approximately 3700 modern humans analyzed. Functional analyses show that this variant reduces MC1R activity to a level that alters hair and/or skin pigmentation in humans. The impaired activity of this variant suggests that Neanderthals varied in pigmentation levels, potentially on the scale observed in modern humans. Our data suggest that inactive MC1R variants evolved independently in both modern humans and Neanderthals.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lalueza-Fox, Carles -- Rompler, Holger -- Caramelli, David -- Staubert, Claudia -- Catalano, Giulio -- Hughes, David -- Rohland, Nadin -- Pilli, Elena -- Longo, Laura -- Condemi, Silvana -- de la Rasilla, Marco -- Fortea, Javier -- Rosas, Antonio -- Stoneking, Mark -- Schoneberg, Torsten -- Bertranpetit, Jaume -- Hofreiter, Michael -- New York, N.Y. -- Science. 2007 Nov 30;318(5855):1453-5. Epub 2007 Oct 25.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Departament de Biologia Animal, Universitat de Barcelona, Spain. clalueza@ub.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17962522" target="_blank"〉PubMed〈/a〉
    Keywords: Alleles ; Amino Acid Substitution ; Animals ; Biological Evolution ; Cell Line ; DNA/genetics ; *Fossils ; Hair Color/*genetics ; Hominidae/*genetics ; Humans ; Molecular Sequence Data ; *Mutation ; Polymerase Chain Reaction ; Receptor, Melanocortin, Type 1/chemistry/*genetics/metabolism ; Sequence Analysis, DNA ; Skin Pigmentation/*genetics
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 7
    Publication Date: 2010-05-08
    Description: Neandertals, the closest evolutionary relatives of present-day humans, lived in large parts of Europe and western Asia before disappearing 30,000 years ago. We present a draft sequence of the Neandertal genome composed of more than 4 billion nucleotides from three individuals. Comparisons of the Neandertal genome to the genomes of five present-day humans from different parts of the world identify a number of genomic regions that may have been affected by positive selection in ancestral modern humans, including genes involved in metabolism and in cognitive and skeletal development. We show that Neandertals shared more genetic variants with present-day humans in Eurasia than with present-day humans in sub-Saharan Africa, suggesting that gene flow from Neandertals into the ancestors of non-Africans occurred before the divergence of Eurasian groups from each other.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Green, Richard E -- Krause, Johannes -- Briggs, Adrian W -- Maricic, Tomislav -- Stenzel, Udo -- Kircher, Martin -- Patterson, Nick -- Li, Heng -- Zhai, Weiwei -- Fritz, Markus Hsi-Yang -- Hansen, Nancy F -- Durand, Eric Y -- Malaspinas, Anna-Sapfo -- Jensen, Jeffrey D -- Marques-Bonet, Tomas -- Alkan, Can -- Prufer, Kay -- Meyer, Matthias -- Burbano, Hernan A -- Good, Jeffrey M -- Schultz, Rigo -- Aximu-Petri, Ayinuer -- Butthof, Anne -- Hober, Barbara -- Hoffner, Barbara -- Siegemund, Madlen -- Weihmann, Antje -- Nusbaum, Chad -- Lander, Eric S -- Russ, Carsten -- Novod, Nathaniel -- Affourtit, Jason -- Egholm, Michael -- Verna, Christine -- Rudan, Pavao -- Brajkovic, Dejana -- Kucan, Zeljko -- Gusic, Ivan -- Doronichev, Vladimir B -- Golovanova, Liubov V -- Lalueza-Fox, Carles -- de la Rasilla, Marco -- Fortea, Javier -- Rosas, Antonio -- Schmitz, Ralf W -- Johnson, Philip L F -- Eichler, Evan E -- Falush, Daniel -- Birney, Ewan -- Mullikin, James C -- Slatkin, Montgomery -- Nielsen, Rasmus -- Kelso, Janet -- Lachmann, Michael -- Reich, David -- Paabo, Svante -- GM40282/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- Intramural NIH HHS/ -- New York, N.Y. -- Science. 2010 May 7;328(5979):710-22. doi: 10.1126/science.1188021.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Evolutionary Genetics, Max-Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany. green@eva.mpg.de〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20448178" target="_blank"〉PubMed〈/a〉
    Keywords: African Continental Ancestry Group/genetics ; Animals ; Asian Continental Ancestry Group/genetics ; Base Sequence ; Bone and Bones ; DNA, Mitochondrial/genetics ; European Continental Ancestry Group/genetics ; Evolution, Molecular ; Extinction, Biological ; Female ; *Fossils ; Gene Dosage ; Gene Flow ; Genetic Variation ; *Genome ; *Genome, Human ; Haplotypes ; Hominidae/*genetics ; Humans ; Pan troglodytes/genetics ; Polymorphism, Single Nucleotide ; Selection, Genetic ; Sequence Alignment ; *Sequence Analysis, DNA ; Time
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 8
    Publication Date: 2010-05-08
    Description: It is now possible to perform whole-genome shotgun sequencing as well as capture of specific genomic regions for extinct organisms. However, targeted resequencing of large parts of nuclear genomes has yet to be demonstrated for ancient DNA. Here we show that hybridization capture on microarrays can successfully recover more than a megabase of target regions from Neandertal DNA even in the presence of approximately 99.8% microbial DNA. Using this approach, we have sequenced approximately 14,000 protein-coding positions inferred to have changed on the human lineage since the last common ancestor shared with chimpanzees. By generating the sequence of one Neandertal and 50 present-day humans at these positions, we have identified 88 amino acid substitutions that have become fixed in humans since our divergence from the Neandertals.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3140021/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3140021/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Burbano, Hernan A -- Hodges, Emily -- Green, Richard E -- Briggs, Adrian W -- Krause, Johannes -- Meyer, Matthias -- Good, Jeffrey M -- Maricic, Tomislav -- Johnson, Philip L F -- Xuan, Zhenyu -- Rooks, Michelle -- Bhattacharjee, Arindam -- Brizuela, Leonardo -- Albert, Frank W -- de la Rasilla, Marco -- Fortea, Javier -- Rosas, Antonio -- Lachmann, Michael -- Hannon, Gregory J -- Paabo, Svante -- P01 CA013106/CA/NCI NIH HHS/ -- P01 CA013106-38/CA/NCI NIH HHS/ -- P01 CA013106-39/CA/NCI NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2010 May 7;328(5979):723-5. doi: 10.1126/science.1188046.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20448179" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Substitution ; Animals ; Fossils ; Genes ; *Genome ; *Genome, Human ; Hominidae/*genetics ; Humans ; Nucleic Acid Hybridization ; Oligonucleotide Array Sequence Analysis/*methods ; Pan troglodytes/genetics ; Proteins/chemistry/genetics ; Sequence Alignment ; Sequence Analysis, DNA/*methods
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 9
    Publication Date: 1997-05-30
    Description: Human fossil remains recovered from the TD6 level (Aurora stratum) of the lower Pleistocene cave site of Gran Dolina, Sierra de Atapuerca, Spain, exhibit a unique combination of cranial, mandibular, and dental traits and are suggested as a new species of Homo-H. antecessor sp. nov. The fully modern midfacial morphology of the fossils antedates other evidence of this feature by about 650, 000 years. The midfacial and subnasal morphology of modern humans may be a retention of a juvenile pattern that was not yet present in H. ergaster. Homo antecessor may represent the last common ancestor for Neandertals and modern humans.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bermudez de Castro, J M -- Arsuaga, J L -- Carbonell, E -- Rosas, A -- Martinez, I -- Mosquera, M -- New York, N.Y. -- Science. 1997 May 30;276(5317):1392-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones Cientificas (CSIC), Departamento de Paleobiologia, J. Gutierrez Abascal 2, 28006 Madrid, Spain.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/9162001" target="_blank"〉PubMed〈/a〉
    Keywords: Adult ; Animals ; Child ; Dentition ; Facial Bones ; *Fossils ; *Hominidae/classification ; Humans ; Mandible ; Skull ; Spain
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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  • 10
    Publication Date: 1995-08-11
    Description: Human remains dating to more than 780,000 years ago are associated with a rich faunal and lithic assemblage in the Pleistocene cave site of Gran Dolina (TD), Sierra de Atapuerca, Burgos, Spain. The micromammal species represent the late Biharian (Mimomys savini zone), and the lithic objects represent pre-Acheulean technology (Mode 1) and comes from the TD6 level below the Matuyama-Brunhes boundary. The Gran Dolina hominid fossils cannot be comfortably accommodated in any of the defined Homo species. They could be considered a primitive form of Homo heidelbergensis, but a new species might be named in the future if the sample is enlarged. The new human fossil evidence demonstrates that Western Europe was settled at least since the late early Pleistocene.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Carbonell, E -- Bermudez de Castro, J M -- Arsuaga, J L -- Diez, J C -- Rosas, A -- Cuenca-Bescos, G -- Sala, R -- Mosquera, M -- Rodriguez, X P -- New York, N.Y. -- Science. 1995 Aug 11;269(5225):826-30.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratori d'Arqueologia, Universitat Rovira i Virgii, Imperial Tarraco, Tarragona, Spain.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7638598" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Fossils ; History, 20th Century ; History, Ancient ; *Hominidae/anatomy & histology/classification ; Humans ; Paleodontology ; Spain ; Tooth/anatomy & histology
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
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