788 research outputs found
mesons in a Bethe-Salpeter model
We apply our Bethe-Salpeter model for mesons to the family with
parameters fixed in our previous investigation. We evaluate the mass of the
pseudo-scalar meson as 6.356 GeV/ and 6.380 GeV/ and the
lifetime as 0.47 ps and 0.46 ps respectively in two reductions of the
Bethe-Salpeter Equation, in good agreement with the recently reported mass of
6.40 0.39 (stat.) 0.13 (syst.) GeV/ and lifetime of
(stat.) 0.03 (syst.) ps by the CDF Collaboration.
We evaluate the decay constant of the meson and compare different
contributions to its decay width.Comment: 9 page
Solar Modulation of Inner Trapped Belt Radiation Flux as a Function of Atmospheric Density
No simple algorithm seems to exist for calculating proton fluxes and lifetimes in the Earth's inner, trapped radiation belt throughout the solar cycle. Most models of the inner trapped belt in use depend upon AP8 which only describes the radiation environment at solar maximum and solar minimum in Cycle 20. One exception is NOAAPRO which incorporates flight data from the TIROS/NOAA polar orbiting spacecraft. The present study discloses yet another, simple formulation for approximating proton fluxes at any time in a given solar cycle, in particular between solar maximum and solar minimum. It is derived from AP8 using a regression algorithm technique from nuclear physics. From flux and its time integral fluence, one can then approximate dose rate and its time integral dose
Mitochondrial phosphatidylethanolamine modulates UCP1 to promote brown adipose thermogenesis
Thermogenesis by uncoupling protein 1 (UCP1) is one of the primary mechanisms by which brown adipose tissue (BAT) increases energy expenditure. UCP1 resides in the inner mitochondrial membrane (IMM), where it dissipates membrane potential independent of adenosine triphosphate (ATP) synthase. Here, we provide evidence that phosphatidylethanolamine (PE) modulates UCP1-dependent proton conductance across the IMM to modulate thermogenesis. Mitochondrial lipidomic analyses revealed PE as a signature molecule whose abundance bidirectionally responds to changes in thermogenic burden. Reduction in mitochondrial PE by deletion of phosphatidylserine decarboxylase (PSD) made mice cold intolerant and insensitive to β3 adrenergic receptor agonist-induced increase in whole-body oxygen consumption. High-resolution respirometry and fluorometry of BAT mitochondria showed that loss of mitochondrial PE specifically lowers UCP1-dependent respiration without compromising electron transfer efficiency or ATP synthesis. These findings were confirmed by a reduction in UCP1 proton current in PE-deficient mitoplasts. Thus, PE performs a previously unknown role as a temperature-responsive rheostat that regulates UCP1-dependent thermogenesis
Characterization of RAPD markers in Vitis
A study was initiated to investigate the possibility of using RAPD markers in related populations of Vitis. We also sought to design primers that could amplify translation initiation sites (Kozak sequence) as a mean to maximize the production of RAPD markers from single copy DNA sequences in the genome. RAPD bands were labeled and used as probes on blots with either genomic DNA or RAPD products from cvs Aurore, Cayuga White, Horizon and Illinois 547-1. Reamplification of excised RAPD products produced either several bands of smaller size, a single band of smaller size or a single band of the same size as the original band. Among 16 probes hybridized to genomic DNA blots, three probes, including one from the Kozak primer amplification, hybridized to 1-2 bands, 5 probes hybridized to 3-8 bands and 8, including two from a Kozak primer reaction, to more than 10 bands on the genomic DNA blots. Twelve RAPD bands were also probed on RAPD blots derived from the RAPD reaction that produced each probe. Three of those probes hybridized to 1-2 bands, 8 hybridized to 3-8 and one hybridized to more than 10 bands indicating the presence of probe sequences in more than one RAPD band as amplified with the same primers. This result and the observations on reamplification of RAPD bands support the hypothesis that some of the longer RAPD fragments harbor internal priming sites that are either not amplified unless the reaction mixture is saturated with longer other primers indicating amplification from the same sequence but different sized repetitive DNA. RAPD reactions were also run with 16 primers on parental DNA of 2 crosses used in genetic mapping (Cayuga White x Aurore and Horizon x Illinois 547-1). These reactions rated 140 bands; 100 bands were shared by both populations, including 47 polymorphic bands. Ten polymorphic bands in Cayuga White x Aurore and 22 in Horizon x Illinois 547-1 were population specific. The RAPD analysis as well as hybridization of RAPD markers to the genomic blots suggest that linkage analysis could be used in related segregating populations with carefully chosen markers. Tagging single copy regions with Kozak-sequence-derived primers may be possible, but the low number of probes tested and lack of DNA sequence information prevents any definite conclusions
Effect of the learning support and the use of project management tools on project success: The case of Pakistan
This study examines the effect of learning support on project success with mediation effect of the use of project management tools. Data were collected form 40 international donor funded projects at federal level in Pakistan. The results suggest that learning support has a positive and significant effect on the use of project management tools which in turn has a similar effect on project success. Results also show that use of project management tools has a significant mediation effect between learning support and the project success. Keywords: Project management, Project management tools, Learning support, International development agencie
Space-efficient Feature Maps for String Alignment Kernels
String kernels are attractive data analysis tools for analyzing string data.
Among them, alignment kernels are known for their high prediction accuracies in
string classifications when tested in combination with SVM in various
applications. However, alignment kernels have a crucial drawback in that they
scale poorly due to their quadratic computation complexity in the number of
input strings, which limits large-scale applications in practice. We address
this need by presenting the first approximation for string alignment kernels,
which we call space-efficient feature maps for edit distance with moves
(SFMEDM), by leveraging a metric embedding named edit sensitive parsing (ESP)
and feature maps (FMs) of random Fourier features (RFFs) for large-scale string
analyses. The original FMs for RFFs consume a huge amount of memory
proportional to the dimension d of input vectors and the dimension D of output
vectors, which prohibits its large-scale applications. We present novel
space-efficient feature maps (SFMs) of RFFs for a space reduction from O(dD) of
the original FMs to O(d) of SFMs with a theoretical guarantee with respect to
concentration bounds. We experimentally test SFMEDM on its ability to learn SVM
for large-scale string classifications with various massive string data, and we
demonstrate the superior performance of SFMEDM with respect to prediction
accuracy, scalability and computation efficiency.Comment: Full version for ICDM'19 pape
PexRAP inhibits PRDM16-mediated thermogenic gene expression
How the nuclear receptor PPARγ regulates the development of two functionally distinct types of adipose tissue, brown and white fat, as well as the browning of white fat, remains unclear. Our previous studies suggest that PexRAP, a peroxisomal lipid synthetic enzyme, regulates PPARγ signaling and white adipogenesis. Here, we show that PexRAP is an inhibitor of brown adipocyte gene expression. PexRAP inactivation promoted adipocyte browning, increased energy expenditure, and decreased adiposity. Identification of PexRAP-interacting proteins suggests that PexRAP function extends beyond its role as a lipid synthetic enzyme. Notably, PexRAP interacts with importin-β1, a nuclear import factor, and knockdown of PexRAP in adipocytes reduced the levels of nuclear phospholipids. PexRAP also interacts with PPARγ, as well as PRDM16, a critical transcriptional regulator of thermogenesis, and disrupts the PRDM16-PPARγ complex, providing a potential mechanism for PexRAP-mediated inhibition of adipocyte browning. These results identify PexRAP as an important regulator of adipose tissue remodeling
Transductive Learning with String Kernels for Cross-Domain Text Classification
For many text classification tasks, there is a major problem posed by the
lack of labeled data in a target domain. Although classifiers for a target
domain can be trained on labeled text data from a related source domain, the
accuracy of such classifiers is usually lower in the cross-domain setting.
Recently, string kernels have obtained state-of-the-art results in various text
classification tasks such as native language identification or automatic essay
scoring. Moreover, classifiers based on string kernels have been found to be
robust to the distribution gap between different domains. In this paper, we
formally describe an algorithm composed of two simple yet effective
transductive learning approaches to further improve the results of string
kernels in cross-domain settings. By adapting string kernels to the test set
without using the ground-truth test labels, we report significantly better
accuracy rates in cross-domain English polarity classification.Comment: Accepted at ICONIP 2018. arXiv admin note: substantial text overlap
with arXiv:1808.0840
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