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Pseudoeurycea unguidentis
Number of Pages: 2Integrative BiologyGeological Science
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Pseudoeurycea longicauda
Number of Pages: 2Integrative BiologyGeological Science
Interchange Reconnection Alfven Wave Generation
Given recent observational results of interchange reconnection processes in
the solar corona and the theoretical development of the S-Web model for the
slow solar wind, we extend the analysis of the 3D MHD simulation of interchange
reconnection by Edmondson et al. (Astrophys. J. 707, 1427, 2009). Specifically,
we analyze the consequences of the dynamic streamer-belt jump that corresponds
to flux opening by interchange reconnection. Information about the magnetic
field restructuring by interchange reconnection is carried throughout the
system by Alfven waves propagating away from the reconnection region,
distributing the shear and twist imparted by the driving flows, including
shedding the injected stress-energy and accumulated magnetic helicity along
newly open fieldlines. We quantify the properties of the reconnection-generated
wave activity in the simulation. There is a localized high-frequency component
associated with the current sheet/reconnection site and an extended
low-frequency component associated with the large-scale torsional Alfven wave
generated from the interchange reconnection field restructuring. The
characteristic wavelengths of the torsional Alfven wave reflect the spatial
size of the energized bipolar flux region. Lastly, we discuss avenues of future
research by modeling these interchange reconnection-driven waves and
investigating their observational signatures.Comment: 18 pages, 7 figures, accepted for publication in Solar Physic
Inference of historical population-size changes with allele-frequency data
With up to millions of nearly neutral polymorphisms now being routinely sampled in population-genomic surveys, it is possible to estimate the site-frequency spectrum of such sites with high precision. Each frequency class reflects a mixture of potentially unique demographic histories, which can be revealed using theory for the probability distributions of the starting and ending points of branch segments over all possible coalescence trees. Such distributions are completely independent of past population history, which only influences the segment lengths, providing the basis for estimating average population sizes separating tree-wide coalescence events. The history of population-size change experienced by a sample of polymorphisms can then be dissected in a model-flexible fashion, and extension of this theory allows estimation of the mean and full distribution of long-term effective population sizes and ages of alleles of specific frequencies. Here, we outline the basic theory underlying the conceptual approach, develop and test an efficient statistical procedure for parameter estimation, and apply this to multiple population-genomic datasets for the microcrustacean Daphnia pulex
The implicit theory of historical change in the work of Alan S. Milward
Alan S. Milward was an economic historian who developed an implicit theory of historical change. His interpretation which was neither liberal nor Marxist posited that social, political, and economic change, for it to be sustainable, had to be a gradual process rather than one resulting from a sudden, cataclysmic revolutionary event occurring in one sector of the economy or society. Benign change depended much less on natural resource endowment or technological developments than on the ability of state institutions to respond to changing political demands from within each society. State bureaucracies were fundamental to formulating those political demands and advising politicians of ways to meet them. Since each society was different there was no single model of development to be adopted or which could be imposed successfully by one nation-state on others, either through force or through foreign aid programs. Nor could development be promoted simply by copying the model of a more successful economy. Each nation-state had to find its own response to the political demands arising from within its society. Integration occurred when a number of nation– states shared similar political objectives which they could not meet individually but could meet collectively. It was not simply the result of their increasing interdependence. It was how and whether nation-states responded to these domestic demands which determined the nature of historical change.historical change,development,World Wars,Third Reich,Blitzkrieg,New Order,Vichy,Fascism,Grossraumwirtschaft,German question,reconstruction,golden age,integration,supranationality,Bretton Woods
The Environmental Contribution to Wayfinding in Museums: Enhancement and Usage by Controlling Flows and Paths
The field of research in which wayfinding is situated refers to the way people move in reaction to environmental stimulation. It therefore fully concerns not just signage but also space designing, its geometric configuration, technical solutions and their material characterization. The focus is consequently on environmental factors that facilitate wayfinding in a museum (accessibility, visibility, etc.) and on other elements such as spatial configuration, architectural features and functional aspects. These factors influence relational phenomena and therefore visitors’ satisfaction. Methods and tools for designing and managing spaces have been studied in the research. The configurational analysis method of space has been used to objectify syntactic features of space. In particular, the outcomes of an experimental project, which have been analyzed in a master’s thesis on the re-functionalization of the museum of Palazzo dei Diamanti in Ferrara, are presented. Permeability, proximity, connections of spaces, namely meaningful features to ensure wayfinding have been examined. Space parameters resulting from the geometry of the layout, from the visual connections and from the changes of direction were then evaluated. The outcomes have been used as inputs for designing a unitary tour route circuit, that also reconnects the museum’s second floor, and for planning three independent alternative routes for a differentiated use of the museum
Statistical multifragmentation model with discretized energy and the generalized Fermi breakup. I. Formulation of the model
The Generalized Fermi Breakup recently demonstrated to be formally equivalent
to the Statistical Multifragmentation Model, if the contribution of excited
states are included in the state densities of the former, is implemented. Since
this treatment requires the application of the Statistical Multifragmentation
Model repeatedly on the hot fragments until they have decayed to their ground
states, it becomes extremely computational demanding, making its application to
the systems of interest extremely difficult. Based on exact recursion formulae
previously developed by Chase and Mekjian to calculate the statistical weights
very efficiently, we present an implementation which is efficient enough to
allow it to be applied to large systems at high excitation energies. Comparison
with the GEMINI++ sequential decay code shows that the predictions obtained
with our treatment are fairly similar to those obtained with this more
traditional model.Comment: 8 pages, 6 figure
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