ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • American Association for the Advancement of Science (AAAS)
  • American Geophysical Union (AGU)
  • 1
    facet.materialart.
    Unknown
    Detection of pulsed gamma rays above 100 GeV from the Crab pulsar (2011)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2011-10-08
    Description: We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga-electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega-electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉VERITAS Collaboration -- Aliu, E -- Arlen, T -- Aune, T -- Beilicke, M -- Benbow, W -- Bouvier, A -- Bradbury, S M -- Buckley, J H -- Bugaev, V -- Byrum, K -- Cannon, A -- Cesarini, A -- Christiansen, J L -- Ciupik, L -- Collins-Hughes, E -- Connolly, M P -- Cui, W -- Dickherber, R -- Duke, C -- Errando, M -- Falcone, A -- Finley, J P -- Finnegan, G -- Fortson, L -- Furniss, A -- Galante, N -- Gall, D -- Gibbs, K -- Gillanders, G H -- Godambe, S -- Griffin, S -- Grube, J -- Guenette, R -- Gyuk, G -- Hanna, D -- Holder, J -- Huan, H -- Hughes, G -- Hui, C M -- Humensky, T B -- Imran, A -- Kaaret, P -- Karlsson, N -- Kertzman, M -- Kieda, D -- Krawczynski, H -- Krennrich, F -- Lang, M J -- Lyutikov, M -- Madhavan, A S -- Maier, G -- Majumdar, P -- McArthur, S -- McCann, A -- McCutcheon, M -- Moriarty, P -- Mukherjee, R -- Nunez, P -- Ong, R A -- Orr, M -- Otte, A N -- Park, N -- Perkins, J S -- Pizlo, F -- Pohl, M -- Prokoph, H -- Quinn, J -- Ragan, K -- Reyes, L C -- Reynolds, P T -- Roache, E -- Rose, H J -- Ruppel, J -- Saxon, D B -- Schroedter, M -- Sembroski, G H -- Senturk, G D -- Smith, A W -- Staszak, D -- Tesic, G -- Theiling, M -- Thibadeau, S -- Tsurusaki, K -- Tyler, J -- Varlotta, A -- Vassiliev, V V -- Vincent, S -- Vivier, M -- Wakely, S P -- Ward, J E -- Weekes, T C -- Weinstein, A -- Weisgarber, T -- Williams, D A -- Zitzer, B -- New York, N.Y. -- Science. 2011 Oct 7;334(6052):69-72. doi: 10.1126/science.1208192.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21980105" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Atmosphere‐Snow Exchange Explains Surface Snow Isotope Variability (2022)
    American Geophysical Union (AGU)
    In:  EPIC3Geophysical Research Letters, American Geophysical Union (AGU), 49(20), pp. e2022gl099529-e2022gl099529, ISSN: 0094-8276
    Details
    Publication Date: 2024-03-14
    Description: The climate signal imprinted in the snow isotopic composition allows to infer past climate variability from ice core stable water isotope records. The concurrent evolution of vapor and surface snow isotopic composition between precipitation events indicates that post-depositional atmosphere-snow humidity exchange influences the snow and hence the ice core isotope signal. To date, however, this is not accounted for in paeleoclimate reconstructions from isotope records. Here we show that vapor-snow exchange explains 36% of the summertime day-to-day δ18O variability of the surface snow between precipitation events, and 53% of the δD variability. Through observations from the Greenland Ice Sheet and accompanying modeling we demonstrate that vapor-snow exchange introduces a warm bias on the summertime snow isotope value relevant for ice core records. In case of long-term variability in atmosphere-snow exchange the relevance for the ice core signal is also variable and thus paleoclimate reconstructions from isotope records should be revisited.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 3
    facet.materialart.
    Unknown
    NAD+ cleavage activity by animal and plant TIR domains in cell death pathways (2019)
    American Association for the Advancement of Science (AAAS)
    In: Science
    Details
    Publication Date: 2019
    Description: 〈p〉SARM1 (sterile alpha and TIR motif containing 1) is responsible for depletion of nicotinamide adenine dinucleotide in its oxidized form (NAD〈sup〉+〈/sup〉) during Wallerian degeneration associated with neuropathies. Plant nucleotide-binding leucine-rich repeat (NLR) immune receptors recognize pathogen effector proteins and trigger localized cell death to restrict pathogen infection. Both processes depend on closely related Toll/interleukin-1 receptor (TIR) domains in these proteins, which, as we show, feature self-association–dependent NAD〈sup〉+〈/sup〉 cleavage activity associated with cell death signaling. We further show that SARM1 SAM (sterile alpha motif) domains form an octamer essential for axon degeneration that contributes to TIR domain enzymatic activity. The crystal structures of ribose and NADP〈sup〉+〈/sup〉 (the oxidized form of nicotinamide adenine dinucleotide phosphate) complexes of SARM1 and plant NLR RUN1 TIR domains, respectively, reveal a conserved substrate binding site. NAD〈sup〉+〈/sup〉 cleavage by TIR domains is therefore a conserved feature of animal and plant cell death signaling pathways.〈/p〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Structural photoactivation of a full-length bacterial phytochrome (2016)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2016-08-14
    Description: Phytochromes are light sensor proteins found in plants, bacteria, and fungi. They function by converting a photon absorption event into a conformational signal that propagates from the chromophore through the entire protein. However, the structure of the photoactivated state and the conformational changes that lead to it are not known. We report time-resolved x-ray scattering of the full-length phytochrome from Deinococcus radiodurans on micro- and millisecond time scales. We identify a twist of the histidine kinase output domains with respect to the chromophore-binding domains as the dominant change between the photoactivated and resting states. The time-resolved data further show that the structural changes up to the microsecond time scales are small and localized in the chromophore-binding domains. The global structural change occurs within a few milliseconds, coinciding with the formation of the spectroscopic meta-Rc state. Our findings establish key elements of the signaling mechanism of full-length bacterial phytochromes.
    Electronic ISSN: 2375-2548
    Topics: Natural Sciences in General
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Topological RPdBi half-Heusler semimetals: A new family of noncentrosymmetric magnetic superconductors (2015)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2015-06-07
    Description: We report superconductivity and magnetism in a new family of topological semimetals, the ternary half-Heusler compound R PdBi ( R : rare earth). In this series, tuning of the rare earth f -electron component allows for simultaneous control of both lattice density via lanthanide contraction and the strength of magnetic interaction via de Gennes scaling, allowing for a unique tuning of the normal-state band inversion strength, superconducting pairing, and magnetically ordered ground states. Antiferromagnetism with ordering vector (1/2,1/2,1/2) occurs below a Néel temperature that scales with de Gennes factor dG, whereas a superconducting transition is simultaneously supressed with increasing dG . With superconductivity appearing in a system with noncentrosymmetric crystallographic symmetry, the possibility of spin-triplet Cooper pairing with nontrivial topology analogous to that predicted for the normal-state electronic structure provides a unique and rich opportunity to realize both predicted and new exotic excitations in topological materials.
    Electronic ISSN: 2375-2548
    Topics: Natural Sciences in General
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Comment on "Observation of alkaline earth complexes M(CO)8 (M = Ca, Sr, or Ba) that mimic transition metals" (2019)
    American Association for the Advancement of Science (AAAS)
    In: Science
    Details
    Publication Date: 2019
    Description: 〈p〉Wu 〈i〉et al〈/i〉. (Reports, 31 August 2018, p. 912) claim that recently characterized octacarbonyls of Ca, Sr, and Ba mimic the classical Dewar-Chatt-Duncanson bonding motif of transition metals. This claim, which contradicts known chemistry and computed electron density distributions, originates in the assumption of a flawed reference state for energy decomposition analyses.〈/p〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Conservation, acquisition, and functional impact of sex-biased gene expression in mammals (2019)
    American Association for the Advancement of Science (AAAS)
    In: Science
    Details
    Publication Date: 2019
    Description: 〈p〉Sex differences abound in human health and disease, as they do in other mammals used as models. The extent to which sex differences are conserved at the molecular level across species and tissues is unknown. We surveyed sex differences in gene expression in human, macaque, mouse, rat, and dog, across 12 tissues. In each tissue, we identified hundreds of genes with conserved sex-biased expression—findings that, combined with genomic analyses of human height, explain ~12% of the difference in height between females and males. We surmise that conserved sex biases in expression of genes otherwise operating equivalently in females and males contribute to sex differences in traits. However, most sex-biased expression arose during the mammalian radiation, which suggests that careful attention to interspecies divergence is needed when modeling human sex differences.〈/p〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Photoactivation of Drosophila melanogaster cryptochrome through sequential conformational transitions (2019)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2019
    Description: 〈p〉Cryptochromes are blue-light photoreceptor proteins, which provide input to circadian clocks. The cryptochrome from 〈i〉Drosophila melanogaster〈/i〉 (〈i〉Dm〈/i〉Cry) modulates the degradation of Timeless and itself. It is unclear how light absorption by the chromophore and the subsequent redox reactions trigger these events. Here, we use nano- to millisecond time-resolved x-ray solution scattering to reveal the light-activated conformational changes in 〈i〉Dm〈/i〉Cry and the related (6-4) photolyase. 〈i〉Dm〈/i〉Cry undergoes a series of structural changes, culminating in the release of the carboxyl-terminal tail (CTT). The photolyase has a simpler structural response. We find that the CTT release in 〈i〉Dm〈/i〉Cry depends on pH. Mutation of a conserved histidine, important for the biochemical activity of 〈i〉Dm〈/i〉Cry, does not affect transduction of the structural signal to the CTT. Instead, molecular dynamics simulations suggest that it stabilizes the CTT in the resting-state conformation. Our structural photocycle unravels the first molecular events of signal transduction in an animal cryptochrome.〈/p〉
    Electronic ISSN: 2375-2548
    Topics: Natural Sciences in General
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    Urbanization and the carbon cycle: Contributions from social science (2014)
    American Geophysical Union (AGU)
    Details
    Publication Date: 2014-08-21
    Description: This paper outlines the contributions of social science to the study of interactions between urbanization patterns and processes and the carbon cycle, and identifies gaps in knowledge and priority areas for future social scientific research contributions. While previously studied as a uni-dimensional process, we conceptualize urbanization as a multi-dimensional, social and biophysical process driven by continuous changes across space and time in various sub-systems including biophysical, built environment and socio-institutional (e.g. economic, political, demographic, behavioral and sociological). We review research trends and findings focused on the socio-institutional subsystem of the urbanization process, and particularly the dynamics, relationships and predictions relevant to energy use and greenhouse gas emissions. Our findings suggest that a multi-dimensional perspective of urbanization facilitates a wider spectrum of research relevant to carbon cycle dynamics, even within the socio-institutional sub-system. However, there is little consensus around the details and mechanisms underlying the relationship between urban socio-institutional subsystems and the carbon cycle. We argue that progress in understanding the relationship between urbanization and the carbon cycle may be achieved if social scientists work collaboratively with each other as well as with scientists from other disciplines. From this review we identify research priorities where collaborative social scientific efforts are necessary in conjunction with other disciplinary approaches to generate a more complete understanding of urbanization as a process and its relationship to the carbon cycle.
    Electronic ISSN: 2328-4277
    Topics: Geosciences
    Published by American Geophysical Union (AGU)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    A critical knowledge pathway to low-carbon, sustainable futures: integrated understanding of urbanization, urban areas and carbon (2014)
    American Geophysical Union (AGU)
    Details
    Publication Date: 2014-08-30
    Description: Independent lines of research on urbanization, urban areas and carbon have advanced our understanding of some of the processes through which energy and land uses affect carbon. This synthesis integrates some of these diverse viewpoints as a first step towards a co-produced, integrated framework for understanding urbanization, urban areas and their relationships to carbon. It suggests the need for approaches that complement and combine the plethora of existing insights into interdisciplinary explorations of how different urbanization processes, and socio-ecological and technological components of urban areas affect the spatial and temporal patterns of carbon emissions, differentially over time and within and across cities. It also calls for a more holistic approach to examining the carbon implications of urbanization and urban areas, based not only on demographics or income, but also on such other interconnected features of urban development pathways as urban form, economic function, economic growth policies and other governance arrangements. It points to a wide array of uncertainties around the urbanization processes, their interactions with urban socio-institutional and built-environment systems, how these impact the exchange of carbon flows within and outside urban areas. We must also understand in turn how carbon feedbacks, including carbon impacts and potential impacts of climate change, can affect urbanization processes. Finally, the paper explores options, barriers and limits to transitioning cities to low-carbon trajectories, and suggests the development of an end-to-end, co-produced and integrated scientific understanding that can more effectively inform the navigation of transitional journeys and the avoidance of obstacles along the way.
    Electronic ISSN: 2328-4277
    Topics: Geosciences
    Published by American Geophysical Union (AGU)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...