7,235 research outputs found
Dynamic Web File Format Transformations with Grace
Web accessible content stored in obscure, unpopular or obsolete formats
represents a significant problem for digital preservation. The file formats
that encode web content represent the implicit and explicit choices of web site
maintainers at a particular point in time. Older file formats that have fallen
out of favor are obviously a problem, but so are new file formats that have not
yet been fully supported by browsers. Often browsers use plug-in software for
displaying old and new formats, but plug-ins can be difficult to find, install
and replicate across all environments that one may use. We introduce Grace, an
http proxy server that transparently converts browser-incompatible and obsolete
web content into web content that a browser is able to display without the use
of plug-ins. Grace is configurable on a per user basis and can be expanded to
provide an array of conversion services. We illustrate how the Grace prototype
transforms several image formats (XBM, PNG with various alpha channels, and
JPEG 2000) so they are viewable in Internet Explorer.Comment: 12 pages, 9 figure
Intrinsic metrics for non-local symmetric Dirichlet forms and applications to spectral theory
We present a study of what may be called an intrinsic metric for a general regular Dirichlet form. For such forms we then prove a Rademacher type theorem. For strongly local forms we show existence of a maximal intrinsic metric (under a weak continuity condition) and for Dirichlet forms with an absolutely continuous jump kernel we characterize intrinsic metrics by bounds on certain integrals. We then turn to applications on spectral theory and provide for (measure perturbation of) general regular Dirichlet forms an Allegretto-Piepenbrinck type theorem, which is based on a ground state transform, and a Shnol type theorem. Our setting includes Laplacian on manifolds, on graphs and α-stable processes
Role of solvent for globular proteins in solution
The properties of the solvent affect the behavior of the solution. We propose
a model that accounts for the contribution of the solvent free energy to the
free energy of globular proteins in solution. For the case of an attractive
square well potential, we obtain an exact mapping of the phase diagram of this
model without solvent to the model that includes the solute-solvent
contribution. In particular we find for appropriate choices of parameters upper
critical points, lower critical points and even closed loops with both upper
and lower critical points, similar to one found before [Macromolecules, 36,
5845 (2003)]. In the general case of systems whose interactions are not
attractive square wells, this mapping procedure can be a first approximation to
understand the phase diagram in the presence of solvent. We also present
simulation results for both the square well model and a modified Lennard-Jones
model.Comment: 18 pages, 9 figure
Discovery of the photosynthetic relatives of the "Maltese mushroom" Cynomorium
BACKGROUND: Although recent molecular phylogenetic studies have identified the photosynthetic relatives of several enigmatic holoparasitic angiosperms, uncertainty remains for the last parasitic plant order, Balanophorales, often considered to include two families, Balanophoraceae and Cynomoriaceae. The nonphotosynthetic (holoparasitic) flowering plant Cynomorium coccineum has long been known to the Muslim world as "tarthuth" and to Europeans as the "Maltese mushroom"; C. songaricum is known in Chinese medicine as "suo yang." Interest in these plants is increasing and they are being extensively collected from wild populations for use in herbal medicines. RESULTS: Here we report molecular phylogenetic analyses of nuclear ribosomal DNA and mitochondrial matR sequence data that strongly support the independent origin of Balanophoraceae and Cynomoriaceae. Analyses of single gene and combined gene data sets place Cynomorium in Saxifragales, possibly near Crassulaceae (stonecrop family). Balanophoraceae appear related to Santalales (sandalwood order), a position previously suggested from morphological characters that are often assumed to be convergent. CONCLUSION: Our work shows that Cynomorium and Balanophoraceae are not closely related as indicated in all past and present classifications. Thus, morphological features, such as inflorescences bearing numerous highly reduced flowers, are convergent and were attained independently by these two holoparasite lineages. Given the widespread harvest of wild Cynomorium species for herbal medicines, we here raise conservation concerns and suggest that further molecular phylogenetic work is needed to identify its photosynthetic relatives. These relatives, which will be easier to cultivate, should then be examined for phytochemical activity purported to be present in the more sensitive Cynomorium
Bringing global gyrokinetic turbulence simulations to the transport timescale using a multiscale approach
The vast separation dividing the characteristic times of energy confinement
and turbulence in the core of toroidal plasmas makes first-principles
prediction on long timescales extremely challenging. Here we report the
demonstration of a multiple-timescale method that enables coupling global
gyrokinetic simulations with a transport solver to calculate the evolution of
the self-consistent temperature profile. This method, which exhibits resiliency
to the intrinsic fluctuations arising in turbulence simulations, holds
potential for integrating nonlocal gyrokinetic turbulence simulations into
predictive, whole-device models.Comment: 7 pages, 3 figure
Farm Operator Satisfaction with Retail Pesticide Suppliers in the Arkansas Delta
Two hundred ninety farm operators in the three easternmost crop reporting districts in Arkansas responded to a mail survey in November 1996 about their preferences and satisfaction with retail pesticide suppliers.Results show most farmers are quite satisfied with their main retail pesticide supplier, although 55.5% of the farm operators used more than one retail pesticide supplier in 1996. Users of multiple suppliers were less satisfied with their suppliers than those using only one supplier. Availability of certain pesticides was the most frequently mentioned reason for using multiple suppliers. Several attributes were important in selecting the main supplier with reputation being the most important, followed by delivery services, long-term relationship with salesperson, and price. Although not rated highly by the farm operators, location was also an important consideration in choosing a main supplier
Acoustically-Driven Phoneme Removal That Preserves Vocal Affect Cues
In this paper, we propose a method for removing linguistic information from
speech for the purpose of isolating paralinguistic indicators of affect. The
immediate utility of this method lies in clinical tests of sensitivity to vocal
affect that are not confounded by language, which is impaired in a variety of
clinical populations. The method is based on simultaneous recordings of speech
audio and electroglottographic (EGG) signals. The speech audio signal is used
to estimate the average vocal tract filter response and amplitude envelop. The
EGG signal supplies a direct correlate of voice source activity that is mostly
independent of phonetic articulation. These signals are used to create a third
signal designed to capture as much paralinguistic information from the vocal
production system as possible -- maximizing the retention of bioacoustic cues
to affect -- while eliminating phonetic cues to verbal meaning. To evaluate the
success of this method, we studied the perception of corresponding speech audio
and transformed EGG signals in an affect rating experiment with online
listeners. The results show a high degree of similarity in the perceived affect
of matched signals, indicating that our method is effective.Comment: Submitted to the 2023 IEEE International Conference on Acoustics,
Speech and Signal Processin
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