3,629 research outputs found

    Analyzing the discharge regime of a large tropical river through remote sensing, ground-based climatic data, and modeling

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    This study demonstrates the potential for applying passive microwave satellite sensor data to infer the discharge dynamics of large river systems using the main stem Amazon as a test case. The methodology combines (1) interpolated ground-based meteorological station data, (2) horizontally and vertically polarized temperature differences (HVPTD) from the 37-GHz scanning multichannel microwave radiometer (SMMR) aboard the Nimbus 7 satellite, and (3) a calibrated water balance/water transport model (WBM/WTM). Monthly HVPTD values at 0.25° (latitude by longitude) resolution were resampled spatially and temporally to produce an enhanced HVPTD time series at 0.5° resolution for the period May 1979 through February 1985. Enhanced HVPTD values were regressed against monthly discharge derived from the WBM/WTM for each of 40 grid cells along the main stem over a calibration period from May 1979 to February 1983 to provide a spatially contiguous estimate of time-varying discharge. HVPTD-estimated flows generated for a validation period from March 1983 to February 1985 were found to be in good agreement with both observed arid modeled discharges over a 1400-km section of the main stem Amazon. This span of river is bounded downstream by a region of tidal influence and upstream by low sensor response associated with dense forest canopy. Both the WBM/WTM and HVPTD-derived flow rates reflect the significant impact of the 1982–1983 El Niño-;Southern Oscillation (ENSO) event on water balances within the drainage basin

    The Saxon Glass Furnaces

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    This is a comprehensive study of the archaeological archives and artefact collections of Glastonbury Abbey, together with a new geophysical survey of the site. It analyses thirty-six seasons of archaeological excavation directed by such iconic figures as Sir William St John Hope, Sir Charles Peers, Sir Alfred Clapham and Dr Courtenay Arthur Ralegh Radford, and reveals new insights into the abbey’s origins and historical development. Previous interpretations are challenged and new evidence is presented for the Saxon and later medieval phases of the abbey, including an important complex of early glass-working furnaces, dated c 700. The study reveals, for the first time, archaeological evidence for the Norman and later medieval monastic ranges and the luxurious abbot’s hall and court

    Can we use Hare’s psychopathy model within forensic and non-forensic populations? An empirical investigation

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    Although psychopathy construct (SRP-SF) was assessed among various samples, prior research did not investigate whether the model proposed by Hare and colleagues can be used to capture psychopathy scores derived from forensic and non-forensic populations. The main objective of the current study was to test dimensionality, construct validity, and factorial invariance of the SRP-SF within prison (N = 730) and student (N = 2,506) samples. Our results indicate that the SRP-SF measure cannot be used in the same way within forensic and non-forensic samples, which may be due to the inclusion of criminal/antisocial traits as an integral part of psychopathy

    A remarkable new butterfly species from western Amazonia (Lepidoptera, Nymphalidae, Satyrinae)

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    A distinctive new species of butterfly in the subtribe Euptychiina (Nymphalidae: Satyrinae), which is widespread throughout the upper Amazon in Colombia, Ecuador and Peru, is here described. The species is provisionally placed in the genus Magneuptychia Forster, 1964, although this is likely to change as the higher level taxonomy of Euptychiina is resolved and the genus is reviewed in detail.Authorisation has been given for this article to be loaded into the NHM repository (email A. Quevedo, Executive Director of ProAves, 17.1.2017). The attached file is the published version

    The Saxon Glass Furnaces

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    The electronic structure of La1−x_{1-x}Srx_{x}MnO3_{3} thin films and its TcT_c dependence as studied by angle-resolved photoemission

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    We present angle-resolved photoemission spectroscopy results for thin films of the three-dimensional manganese perovskite La1−x_{1-x}Srx_{x}MnO3_{3}. We show that the transition temperature (TcT_c) from the paramagnetic insulating to ferromagnetic metallic state is closely related to details of the electronic structure, particularly to the spectral weight at the k{\bf k}-point, where the sharpest step at the Fermi level was observed. We found that this k{\bf k}-point is the same for all the samples, despite their different TcT_c. The change of TcT_c is discussed in terms of kinetic energy optimization. Our ARPES results suggest that the change of the electronic structure for the samples having different transition temperatures is different from the rigid band shift.Comment: Accepted by Journal of Physics: Condensed Matte

    Profiling the interface electron gas of LaAlO3/SrTiO3 heterostructures by hard X-ray photoelectron spectroscopy

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    The conducting interface of LaAlO3_3/SrTiO3_3 heterostructures has been studied by hard X-ray photoelectron spectroscopy. From the Ti~2pp signal and its angle-dependence we derive that the thickness of the electron gas is much smaller than the probing depth of 4 nm and that the carrier densities vary with increasing number of LaAlO3_3 overlayers. Our results point to an electronic reconstruction in the LaAlO3_3 overlayer as the driving mechanism for the conducting interface and corroborate the recent interpretation of the superconducting ground state as being of the Berezinskii-Kosterlitz-Thouless type.Comment: 4 pages, 4 figure
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