2,271 research outputs found
Change of Interest as a Function of Shift in Curricular Orientation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67119/2/10.1177_001316445301300213.pd
A randomized controlled trial to evaluate the role of interferon as initial and maintenance therapy in patients with follicular lymphoma
The purpose of this study was to evaluate the role of interferon as initial and maintenance therapy in patients with newly diagnosed follicular lymphoma. Between 1984 and 1994, 204 patients with newly diagnosed Stage III or Stage IV follicular lymphoma were randomized to receive either, Chlorambucil (CB): 10 mg daily for 6 weeks, followed by a 2-week interval, with 3 subsequent 2-week treatment periods at the same dose, separated by 2-week intervals, or, CB given concurrently with interferon (IFN). IFN was given at a dose of 3 × 106units thrice weekly, subcutaneously, throughout the 18-week treatment period. Responding patients were subsequently randomized to receive maintenance IFN at the dose and schedule described above, or to expectant management. The overall response rate was 161/204 (78%), complete remission being achieved in 24% of patients. Neither the addition of IFN to the initial treatment, nor the use of maintenance IFN influenced response rate, remission duration or survival. This study was undertaken to determine whether IFN, given in combination with, and then subsequent to, CB would alter the clinical course of patients with follicular lymphoma. Disappointingly, this objective was not achieved, no advantage having been demonstrated for the addition of IFN. © 2001 Cancer Research Campaign http://www.bjcancer.co
The diversity of bioactive proteins in Australian snake venoms
Australian elapid snakes are among the most venomous in the world. Their venoms contain multiple components that target blood hemostasis, neuromuscular signaling, and the cardiovascular system. We describe here a comprehensive approach to separation and identification of the venom proteins from 18 of these snake species, representing nine genera. The venom protein components were separated by two-dimensional PAGE and identified using mass spectrometry and de novo peptide sequencing. The venoms are complex mixtures showing up to 200 protein spots varying in size from 10. These include many proteins identified previously in Australian snake venoms, homologs identified in other snake species, and some novel proteins. In many cases multiple trains of spots were typically observed in the higher molecular mass range (> 20 kDa) (indicative of post-translational modification). Venom proteins and their post-translational modifications were characterized using specific kantibodies, phosphoprotein- and glycoprotein-specific stains, enzymatic digestion, lectin binding, and antivenom reactivity. In the lower molecular weight range, several proteins were identified, but the predominant species were phospholipase A(2) and alpha-neurotoxins, both represented by different sequence variants. The higher molecular weight range contained proteases, nucleotidases, oxidases, and homologs of mammalian coagulation factors. This information together with the identification of several novel proteins (metalloproteinases, vespryns, phospholipase A(2) inhibitors, protein-disulfide isomerase, 5'-nucleotidases, cysteinerich secreted proteins, C-type lectins, and acetylcholinesterases) aids in understanding the lethal mechanisms of elapid snake venoms and represents a valuable resource for future development of novel human therapeutics
Feedback-optimized parallel tempering Monte Carlo
We introduce an algorithm to systematically improve the efficiency of
parallel tempering Monte Carlo simulations by optimizing the simulated
temperature set. Our approach is closely related to a recently introduced
adaptive algorithm that optimizes the simulated statistical ensemble in
generalized broad-histogram Monte Carlo simulations. Conventionally, a
temperature set is chosen in such a way that the acceptance rates for replica
swaps between adjacent temperatures are independent of the temperature and
large enough to ensure frequent swaps. In this paper, we show that by choosing
the temperatures with a modified version of the optimized ensemble feedback
method we can minimize the round-trip times between the lowest and highest
temperatures which effectively increases the efficiency of the parallel
tempering algorithm. In particular, the density of temperatures in the
optimized temperature set increases at the "bottlenecks'' of the simulation,
such as phase transitions. In turn, the acceptance rates are now temperature
dependent in the optimized temperature ensemble. We illustrate the
feedback-optimized parallel tempering algorithm by studying the two-dimensional
Ising ferromagnet and the two-dimensional fully-frustrated Ising model, and
briefly discuss possible feedback schemes for systems that require
configurational averages, such as spin glasses.Comment: 12 pages, 14 figure
Search for nucleon decay via modes favored by supersymmetric grand unification models in Super-Kamiokande-I
We report the results for nucleon decay searches via modes favored by
supersymmetric grand unified models in Super-Kamiokande. Using 1489 days of
full Super-Kamiokande-I data, we searched for , , and modes. We found no
evidence for nucleon decay in any of these modes. We set lower limits of
partial nucleon lifetime 2.3, 1.3,
1.3 and 1.0 years at 90% confidence level for , , and modes, respectively. These results give a strong constraint on
supersymmetric grand unification models.Comment: 14 pages, 13 figure
Search for Dark Matter WIMPs using Upward Through-going Muons in Super-Kamiokande
We present the results of indirect searches for Weakly Interacting Massive
Particles (WIMPs) with 1679.6 live days of data from the Super-Kamiokande
detector using neutrino-induced upward through-going muons. The search is
performed by looking for an excess of high energy muon neutrinos from WIMP
annihilations in the Sun, the core of the Earth, and the Galactic Center, as
compared to the number expected from the atmospheric neutrino background. No
statistically significant excess was seen. We calculate flux limits in various
angular cones around each of the above celestial objects. We obtain
conservative model-independent upper limits on WIMP-nucleon cross-section as a
function of WIMP mass and compare these results with the corresponding results
from direct dark matter detection experiments.Comment: 10 pages, 14 figures, Submitted to Phys. Rev.
Observation of the east-west anisotropy of the atmospheric neutrino flux
The east-west anisotropy, caused by the deflection of primary cosmic rays in
the Earth's magnetic field, is observed for the first time in the flux of
atmospheric neutrinos. Using a 45 kt-year exposure of the
Super-Kamiokande detector, 552 e-like and 633 mu-like horizontally-going
events are selected in the momentum range between 400 and 3000 MeV/c.
The azimuthal distribution of e-like and mu-like events agrees with the
expectation from atmospheric neutrino flux calculations that account for the
geomagnetic field, verifying that the geomagnetic field effects in the
production of atmospheric neutrinos in the GeV energy range are well
understood.Comment: 8 pages,3 figures revtex, submitted to PR
A search for periodic modulations of the solar neutrino flux in Super-Kamiokande-I
A search for periodic modulations of the solar neutrino flux was performed
using the Super-Kamiokande-I data taken from May 31st, 1996 to July 15th, 2001.
The detector's capability of measuring the exact time of events, combined with
a relatively high yield of solar neutrino events, allows a search for
short-time variations in the observed flux. We employed the Lomb test to look
for periodic modulations of the observed solar neutrino flux. The obtained
periodogram is consistent with statistical fluctuation and no significant
periodicity was found
Limit On the Neutrino Magnetic Moment Using 1496 Days of Super-Kamiokande-i Solar Neutrino Data
A search for a non-zero neutrino magnetic moment has been conducted using
1496 live days of solar neutrino data from {\SK}. Specifically, we searched for
distortions to the energy spectrum of recoil electrons arising from magnetic
scattering due to a non-zero neutrino magnetic moment. In the absence of clear
signal, we found at 90% C.L. by
fitting to the Super-Kamiokande day/night spectra. The fitting took into
account the effect of neutrino oscillation on the shapes of energy spectra.
With additional information from other solar neutrino and KamLAND experiments
constraining the oscillation region, a limit of at 90% C.L. was obtained.Comment: 5 pages, 4 figure
Search for Supernova Relic Neutrinos at Super-Kamiokande
A search for the relic neutrinos from all past core-collapse supernovae was
conducted using 1496 days of data from the Super-Kamiokande detector. This
analysis looked for electron-type anti-neutrinos that had produced a positron
with an energy greater than 18 MeV. In the absence of a signal, 90% C.L. upper
limits on the total flux were set for several theoretical models; these limits
ranged from 20 to 130 nu_e bar cm^-2 s^-1. Additionally, an upper bound of 1.2
nu_e bar cm^-2 s^-1 was set for the supernova relic neutrino flux in the energy
region E_nu > 19.3 MeV.Comment: 4 pages, 2 figures. Submitted to Physical Review Letters. New version
includes corrections to Figure 1. Also, text has been shortened to conform
with the space limitations of PR
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