280 research outputs found
Ten Misconceptions from the History of Analysis and Their Debunking
The widespread idea that infinitesimals were "eliminated" by the "great
triumvirate" of Cantor, Dedekind, and Weierstrass is refuted by an
uninterrupted chain of work on infinitesimal-enriched number systems. The
elimination claim is an oversimplification created by triumvirate followers,
who tend to view the history of analysis as a pre-ordained march toward the
radiant future of Weierstrassian epsilontics. In the present text, we document
distortions of the history of analysis stemming from the triumvirate ideology
of ontological minimalism, which identified the continuum with a single number
system. Such anachronistic distortions characterize the received interpretation
of Stevin, Leibniz, d'Alembert, Cauchy, and others.Comment: 46 pages, 4 figures; Foundations of Science (2012). arXiv admin note:
text overlap with arXiv:1108.2885 and arXiv:1110.545
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
A Study of Exclusive Charmless Semileptonic B Decays and Extraction of |V_{ub}| at CLEO
We have studied semileptonic B decay to the exclusive charmless states pi,
rho/omega, eta and eta' using the full 15.5 fb^-1 CLEO Upsilon(4S) sample, with
measurements performed in subregions of phase space to minimize dependence on a
priori knowledge of the form factors involved. We find total branching
fractions B(B^0 -> pi^-l^+nu) = (1.37 +- 0.15_stat +- 0.11_sys) x 10^-4 and
B(B^0 -> rho^- l^+ nu) = (2.93 +- 0.37_stat +- 0.37_sys) x 10^-4. We find
evidence for B^+ -> eta' l^+ nu, with B(B^+ -> eta' l^+ nu) = (2.66 +-
0.80_stat +- 0.56_sys) x 10^-4 and 1.20 x 10^-4 eta' l^+ nu) < 4.46
x 10^-4 (90% CL). We also limit B(B^+ -> eta l^+ nu) < 1.01 x 10^-4 (90% CL).
By combining our B -> pi l nu information with unquenched lattice calculations,
we find |V_ub| = (3.6 +- 0.4 +- 0.2 +0.6 -0.4) x 10^-3, where the errors are
statistical, experimental systematic, and theoretical systematic, respectively.Comment: 35 pages, 15 figures; revise
Resonant Structure of and Decays
The resonant structure of the four pion final state in the decay is analyzed using 4.27 million pairs
collected by the CLEO II experiment. We search for second class currents in the
decay using spin-parity analysis and establish an
upper limit on the non-vector current contribution. The mass and width of the
resonance are extracted from a fit to the
spectral function. A partial wave analysis of the resonant structure of the
decay is performed; the spectral decomposition of
the four pion system is dominated by the and final
states.Comment: 34 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLN
Search for Lepton-Flavor-Violating Decays of B Mesons
We have searched a sample of 9.6 million BB-bar events for the
lepton-flavor-violating decays B --> h e^{+-} mu^{-+}, B^+ --> h^- e^+ e^+, B^+
--> h^- e^+ mu^+, and B^+ --> h^- mu^+ mu^+, where h is pi, K, rho, and
K*(892), a total of sixteen modes. We find no evidence for these decays, and
place 90% confidence level upper limits on their branching fractions that range
from 1.0 to 8.3 X 10^{-6}.Comment: 8 pages postscript, also available through
http://w4.lns.cornell.edu/public/CLNS, PRD R
Determination of the Michel Parameters and the tau Neutrino Helicity in tau Decay
Using the CLEO II detector at the storage ring CESR, we have
determined the Michel parameters , , and in decay as well as the tau neutrino helicity parameter
in decay. From a data sample of
tau pairs produced at , using events of
the topology and , and the determined sign of , the combined
result of the three samples is: , , , and
. The results are in agreement with
the Standard Model V-A interaction.Comment: 18 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Measurement of the Branching Ratios for the Decays of , and
Using a data sample with integrated luminosity of about 3.9 fb^{-1} collected
in e+ e- annihilation with the CLEO-II detector at the Cornell Electron Storage
Ring, we have measured the branching ratios for the decay modes Ds -> (eta,
eta') pi and Ds -> (eta, eta') rho relative to Ds -> phi pi. These decay modes
are among the most common hadronic decays of the Ds's and can be related by
factorization to the semileptonic decays Ds -> (eta,eta') l nu. The results
obtained are compared with previous CLEO results and with the branching ratios
measured for the related semileptonic decays. We also report results on the
Cabibbo-suppressed decays of the D+ to the same final states.Comment: 18 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Search for Exclusive Charmless Hadronic B Decays
We have searched for two-body charmless hadronic decays of mesons. Final
states include , , and with both charged and neutral kaons
and pions; , , and ; and , , and
. The data used in this analysis consist of 2.6~million
~pairs produced at the taken with the CLEO-II detector
at the Cornell Electron Storage Ring (CESR). We measure the branching fraction
of the sum of and to be
. In addition, we place upper
limits on individual branching fractions in the range from to
.Comment: 33 page LATEX file, uses REVTEX and psfig, 14 figures in a separate
uuencoded postscript file, postscript version also available through
http://w4.lns.cornell.edu/public/CLN
Tau Neutrino Helicity from Energy Correlations
We report a measurement of the magnitude of the tau neutrino helicity from
tau-pair events taken with the CLEO detector at the CESR electron-positron
storage ring. Events in which each tau undergoes the decay tau -> h nu, with h
a charged pion or kaon, are analyzed for energy correlations between the
daughter hadrons, yielding |xi| = 2*|h_nu| = 1.03 +/- 0.06 +/- 0.04, with the
first error statistical and the second systematic.Comment: 11 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Limit on the Two-Photon Production of the Glueball Candidate at CLEO
We use the CLEO detector at the Cornell electron-positron storage ring, CESR,
to search for the two-photon production of the glueball candidate f_J(2220) in
its decay to K_s K_s. We present a restrictive upper limit on the product of
the two-photon partial width and the K_s K_s branching fraction. We use this
limit to calculate a lower limit on the stickiness, which is a measure of the
two-gluon coupling relative to the two-photon coupling. This limit on
stickiness indicates that the f_J(2220) has substantial glueball content.Comment: 9 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
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