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The distribution of butterflies was mapped throughout entire Estonia in 2016 and 2017. Butterflies were surveyed during three phenologically targeted visits at more than 1200 pre-selected sites. In total, over 180 000 individuals ...
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The distribution of butterflies was mapped throughout entire Estonia in 2016 and 2017. Butterflies were surveyed during three phenologically targeted visits at more than 1200 pre-selected sites. In total, over 180 000 individuals belonging to 97 species were recorded. We compare the resulting distribution maps with historical records, and discuss changes in the species' distribution. We conclude that, within the time frame of century, the changes in the Estonian butterfly fauna were moderate. For about 75% of species, there was no conclusive evidence of a change in distribution or abundance. In case of the remaining 25%, there were more butterfly species with an increasing rather than a decreasing trend in abundance and/or distribution. Some but not all of those changes could be associated with ongoing climate change. The decline of several drymeadow specialists can be regarded as the most urgent conservation concern.
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We infer rates of crustal deformation in the northern Walker Lane (NWL) and western Basin and Range using data from the Mobile Array of GPS for Nevada transtension, and other continuous GPS networks including the EarthScope Plate ...
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We infer rates of crustal deformation in the northern Walker Lane (NWL) and western Basin and Range using data from the Mobile Array of GPS for Nevada transtension, and other continuous GPS networks including the EarthScope Plate Boundary Observatory. We present 224 new GPS velocities, correct them for the effects of viscoelastic postseismic relaxation, and use them to constrain a block model to estimate fault slip rates. The data segregate the NWL into domains based on differences in deformation rate, pattern, and style. Deformation is transtensional, with highest rates near the western and eastern edges of the NWL. Some basins, e.g., Tahoe, experience shear deformation and extension. Normal slip is distributed throughout the NWL and Basin and Range, where 11 subparallel range-bounding normal fault systems have an average horizontal extension rate of 0.1 mm/yr. Comparison between Geol.ogic and geodetic slip rates indicates that out of 12 published Geol.ogic rates, 10 agree with geodetic rates to within uncertainties. This suggests that smaller crustal blocks move steadily, similar to larger lithospheric plates, and that geodetic measurements of slip rates are reliable in zones of complex crustal deformation. For the two slip rates that disagree, Geol.ogic rates are greater. The vertical axis rotation rate of the Carson domain is –1.3 ± 0.1°/My clockwise, lower than the 3° to 6°/My obtained in paleomagnetic measurements. This suggests that vertical axis rotation rates may have decreased over the last 9-13 My as the role of faulting has increased at the expense of rigid rotations.
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The single-particle potential for nucleons and hyperons in neutron-rich matter generally depends on the density and isospin asymmetry of the medium as well as the momentum and isospin of the particle. It further depends on the tem...
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The single-particle potential for nucleons and hyperons in neutron-rich matter generally depends on the density and isospin asymmetry of the medium as well as the momentum and isospin of the particle. It further depends on the temperature of the matter if the latter is in thermal equilibrium. We review here the extension of a Gogny-type isospin- and momentum-dependent interactions in several aspects made in recent years and their applications in studying intermediate-energy heavy-ion collisions, thermal properties of asymmetric nuclear matter and properties of neutron stars. The importance of the isospin and momentum dependence of the single-particle potential, especially the momentum dependence of the isovector potential, is clearly revealed throughout these studies.
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1.txt Transcription represents the first step in gene expression. It is therefore not surprising that transcription is a highly regulated process and its control is essential to understand the flow and processing of information re...
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1.txt Transcription represents the first step in gene expression. It is therefore not surprising that transcription is a highly regulated process and its control is essential to understand the flow and processing of information required by the cell to maintain its homeostasis. During transcription, a DNA molecule is copied into RNA molecules that are then used to translate the genetic information into proteins; this logical pattern has been conserved throughout all three kingdoms of life, from Archaea to Eukarya, making it an essential and fundamental cellular process. Even though some viruses that encode their genome in an RNA molecule use it as a template to make mRNA, others synthesize an intermediate DNA molecule from the RNA, a process known as reverse transcription, from which regular transcription of viral genes can then proceed in the host cells.
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We study temporal changes in seismicity in Sumatra-Andaman Islands region before the M 9.1 earthquake of December 26, 2004. We applied the epidemic type aftershock sequence (ETAS) models to the seismicity. The two-stage non-statio...
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We study temporal changes in seismicity in Sumatra-Andaman Islands region before the M 9.1 earthquake of December 26, 2004. We applied the epidemic type aftershock sequence (ETAS) models to the seismicity. The two-stage non-stationary ETAS model with a single change-point provides a better statistical fit to the seismicity data than the stationary ETAS model throughout the whole period. We made further change-point analysis of data sets by dividing into two sub-regions. The best fitted models suggest that the seismic activation relative to the ETAS rates started in the middle of July 2000 (about 4.5 years before the M 9.1 earthquake). This includes an increase in the background seismicity rates, particularly in the southern part of the seismogenic zone near the epicenter. A space-time ETAS model also suggests that the background seismicity throughout the entire Sumatra-Andaman Islands area had increased after the change-point time.
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One of the great continental rifts in all of Earth’s history, the ca. 1.1-Ga Midcontinent Rift of the Lake Superior region, was closed and inverted less than 100 m.yr. after its initiation, when rift-bounding normal faults were r...
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One of the great continental rifts in all of Earth’s history, the ca. 1.1-Ga Midcontinent Rift of the Lake Superior region, was closed and inverted less than 100 m.yr. after its initiation, when rift-bounding normal faults were reactivated as reverse faults. This was a major crustal event involving “thick-skinned” deformation, but its tectonic importance has not been fully appreciated, owing in part to the lack of good outcrop along the traces of the riftclosing faults. A rare exposure of one of these faults occurs near the falls of the Marengo River in southeastern Bayfield County, Wisconsin. The Atkins Lake–Marenisco fault is a crustal-scale structure that juxtaposes Archean granitic gneisses with Paleoproterozoic and Neoproterozoic metasedimentary and metavolcanic rocks. Pseudotachylytes, cataclasites, and microbreccias in the fault zone record large (M~7) seismic events at midcrustal levels, followed by a protracted period of frictional wear and intermittent fluidization of fine-grained material along the fault. Pervasive vein networks indicate that the zone acted as a conduit for fluids throughout its history. Slip on the Atkins Lake– Marenisco zone and other rift-closing faults occurred at the same time as the widely known but poorly understood hydrothermal copper mineralization in northern Michigan and Wisconsin. Recent hydrologic simulations of the relationships among deformation, permeability, and fluid flow in midcrustal fault zones suggest that reverse slip on reactivated rift-bounding faults may have triggered both upward and downward fluid flow, and this may help to explain the complex geochemical and isotopic signatures of hydrothermal mineral assemblages along the margins of the Midcontinent Rift. The regional structure and outcrop-scale features of the Atkins Lake–Marenisco fault zone require that significant horizontal stresses, presumably from the coeval Grenville orogen, were transmitted far into the interior of the continent, more than 500 km west of the conventional placement of the Grenville Front.
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Increased urban development throughout the United States has resulted in greater levels of mortality for many avian species caused by bird-window collisions (BWCs). Current annual estimates of BWCs are very broad and often do not ...
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Increased urban development throughout the United States has resulted in greater levels of mortality for many avian species caused by bird-window collisions (BWCs). Current annual estimates of BWCs are very broad and often do not account for the influence of various factors such as building size, window area, window reflectivity or transmittance, proportion of development or bird habitat near buildings, and species vulnerability. During this preliminary study, we assessed how building type and features, en- vironmentalland cover surrounding buildings, and species factors were related to fatal BWCs. In the fall of 2014, we documented the number of bird carcasses resulting from window collisions at six study buildings on the University of Wisconsin-Platteville campus. We conducted daily carcass surveys around the perimeter of each study building for 21 consecutive days (18 Sep through 8 Oct) during the fall migration season. As a result, eleven carcasses were recovered comprising seven known and one unknown species. All but one carcass was found at the two largest buildings; these that also had the greatest window area. BWCs were unrelated to window reflectivity, window transmit- tance, or land cover around the buildings. The Ruby-throated Hummingbird (Archi- lochus colubris) was the most prevalent species found (27%). We recommend that further research be done to clarify the impact of window reflectivity, transmittance, and land cover types on BWCs. To minimize the risk of BWCs, as well as promoting avian conservation, we offer suggestions (e.g., ultraviolet signal stripes and landscaping) on how to limit the number of fatalities that occur due to window collisions.
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Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. T...
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Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. This column focuses on the usability testing conducted at Alden Library and delves into future usability testing, which will utilize several different types of usability testing software. For those well versed in usability testing, the methods presented below will probably be old, familiar friends. For those that have not added usability testing to their repertoire, do not be intimidated as you will see usability testing is quite manageable.
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he seasonal evolution of the aerosol vertical distribution in the Central Mediterranean is studied using measurements made in the period 1999-2008 at Lampedusa with an aerosol Lidar and a multi filter rotating shadowband radiomete...
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he seasonal evolution of the aerosol vertical distribution in the Central Mediterranean is studied using measurements made in the period 1999-2008 at Lampedusa with an aerosol Lidar and a multi filter rotating shadowband radiometer (MFRSR). Measurements show that the aerosol vertical distribution is largely influenced by Saharan dust, which produces a strong annual cycle both in aerosol vertical extension and optical depth. Dust layers are present in the profile in 38% of the cases throughout the year, and in 57% in summer. The dust top altitude peaks in late spring, up to 9 km. The monthly average optical depth at 500 nm for dust cases shows a main peak in July (0.38), and values exceeding 0.2 throughout March–September. Conversely, non-dust cases show a very limited seasonality, both in vertical distribution and aerosol optical depth. The monthly average optical depth for non-dust cases is smaller than 0.17 throughout the year. During winter, the vertical distribution and optical depth are very similar for both dust and non-dust cases. The seasonal average extinction coefficient profiles for dust and non-dust cases show remarkable differences in spring and summer, when values of the extinction coefficient exceed 0.5 x 10-4 m-1 throughout the altitude range 0-4.5 km for dust cases, and 0-1 km altitude for non-dust cases, respectively. Estimates of the Lidar Ratio are derived by combining Lidar and MFRSR measurements. The average Lidar Ratio at 532 nm is about 30 sr.
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Samples of nanoscale hematite, α-Fe_2O_3, with different surface geometries and properties have been studied with inelastic time-of-flight neutron scattering. The 15 nm diameter nanoparticles previously shown to have two collecti...
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Samples of nanoscale hematite, α-Fe_2O_3, with different surface geometries and properties have been studied with inelastic time-of-flight neutron scattering. The 15 nm diameter nanoparticles previously shown to have two collective magnetic excitation modes in separate triple-axis neutron scattering studies have been studied in further detail using the advantage of a large detector area, high resolution, and large energy transfer range of the IN5 TOF spectrometer. A mesoporous hematite sample has also been studied, showing similarities to that of the nanoparticle sample and bulk α-Fe_2O_3. Analysis of these modes provides temperature dependence of the magnetic anisotropy coefficient along the c-axis, κ_1. This is shown to remain negative throughout the temperature range studied in both samples, providing an explanation for the previously observed suppression of the Morin transition in the mesoporous material. The values of this anisotropy coefficient are found to lie between those of bulk and nano-particulate samples, showing the hybrid nature of the mesoporous 3-dimensional structure.
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