137 research outputs found
Interaction and Localization of One-electron Orbitals in an Organic Molecule: Fictitious Parameter Analysis for Multi-physics Simulations
We present a new methodology to analyze complicated multi-physics simulations
by introducing a fictitious parameter. Using the method, we study quantum
mechanical aspects of an organic molecule in water. The simulation is
variationally constructed from the ab initio molecular orbital method and the
classical statistical mechanics with the fictitious parameter representing the
coupling strength between solute and solvent. We obtain a number of
one-electron orbital energies of the solute molecule derived from the
Hartree-Fock approximation, and eigenvalue-statistical analysis developed in
the study of nonintegrable systems is applied to them. Based on the results, we
analyze localization properties of the electronic wavefunctions under the
influence of the solvent.Comment: 4 pages, 5 figures, the revised version will appear in J. Phys. Soc.
Jpn. Vol.76 (No.1
Adherence to Competing Strategies for Colorectal Cancer Screening Over 3 Years
We have shown that, in a randomized trial comparing adherence to different colorectal cancer (CRC) screening strategies, participants assigned to either fecal occult blood testing (FOBT) or given a choice between FOBT and colonoscopy had significantly higher adherence than those assigned to colonoscopy during the first year. However, how adherence to screening changes over time is unknown
Observations of the Origin of Downward Terrestrial Gamma-Ray Flashes
In this paper we report the first close, high-resolution observations of downward-directed terrestrial gamma-ray flashes (TGFs) detected by the large-area Telescope Array cosmic ray observatory, obtained in conjunction with broadband VHF interferometer and fast electric field change measurements of the parent discharge. The results show that the TGFs occur during strong initial breakdown pulses (IBPs) in the first few milliseconds of negative cloud-to-ground and low-altitude intracloud flashes and that the IBPs are produced by a newly identified streamer-based discharge process called fast negative breakdown. The observations indicate the relativistic runaway electron avalanches (RREAs) responsible for producing the TGFs are initiated by embedded spark-like transient conducting events (TCEs) within the fast streamer system and potentially also by individual fast streamers themselves. The TCEs are inferred to be the cause of impulsive sub-pulses that are characteristic features of classic IBP sferics. Additional development of the avalanches would be facilitated by the enhanced electric field ahead of the advancing front of the fast negative breakdown. In addition to showing the nature of IBPs and their enigmatic sub-pulses, the observations also provide a possible explanation for the unsolved question of how the streamer to leader transition occurs during the initial negative breakdown, namely, as a result of strong currents flowing in the final stage of successive IBPs, extending backward through both the IBP itself and the negative streamer breakdown preceding the IBP
Phase II trial of intralesional therapy with interleukin-2 in soft-tissue melanoma metastases
Race and Inflammatory Bowel Disease in an Urban Healthcare System
Inflammatory bowel disease (IBD) is increasingly common among non-Caucasian populations, but interracial differences in disease characteristics and management are not well-characterized.
We tested the hypothesis that disease characteristics and management vary by race among IBD patients in an ethnically diverse healthcare system.
A retrospective study of the safety net healthcare system of San Francisco, CA, from 1996 to 2009 was undertaken. Patient records with International Classification of Diseases, 9th Revision (ICD9) codes 555.xx, 556.xx, and 558.xx were reviewed. Adult patients with confirmed IBD diagnoses were included. Interracial variations in disease characteristics and management were assessed broadly; focused between-race comparisons identified specific differences.
The 228 subjects included 77 (33.4%) with Crohn’s disease (CD), 150 (65.8%) with ulcerative colitis, and 1 (0.4%) with IBD, type unclassified. The race distribution included 105 (46.1%) white, 34 (14.9%) black, 35 (15.4%) Hispanic, and 51 (22.4%) Asian subjects. Asians and Hispanics were diagnosed at older ages (41.0 and 37.1 years, respectively) and had shorter disease durations (5.4 and 5.2 years, respectively) than whites (30.5 years at diagnosis and 8.6 years duration, P < 0.05) and blacks (31.7 years at diagnosis and 12.1 years duration, P < 0.05). CD was more common among blacks (50% of subjects) than Asians (25.5% of subjects, P = 0.015). The Montreal classification of IBD was similar among races. Hispanics were less likely than others to be treated with 5-aminosalicylates (5-ASA), immunomodulators, and steroids. Medical and surgical management was otherwise similar among races.
Modest race-based differences in IBD characteristics exist in this racially diverse healthcare system, but the management of IBD is similar among race groups
Implications of Epigenetic Drift in Colorectal Neoplasia
NIH grants U01CA182940 (G.E. Luebeck, W.D. Hazelton, W.M. Grady, S.K. Madden, K. Curtius), U01CA199336 (G.E. Luebeck, W.D. Hazelton); Barts Charity grant 472-2300, London (K. Curtius) and UK Medical Research Council Rutherford fellowship (K. Curtius); and NIH grants (P30CA15704, U01CA152756, R01CA194663, R01CA220004, U54CA143862, P01CA077852),R.A.C.E. Charities, Cottrell Family Fund, R03CA165153, Listwin Family Foundation, Seattle Translational Tumor Research program, Fred Hutchinson Cancer Research Center (S.K. Madden, M. Yu, K.T. Carter, and W.M. Grady), R01CA189184 (C. Lee, C.M. Ulrich, S.K.Madden, M. Yu, K.T. Carter, and W.M. Grady), R01CA112516, R01CA114467, R01CA120523
(C.M. Ulrich, S.K. Madden, M. Yu, K.T. Carter, and W.M. Grady), Huntsman Cancer
Foundation, U01 CA206110, R01CA189184 R01CA 207371 and P30CACA042014 (C.M.
Ulrich). U24CA074794 (P.A. Newcomb, S.K. Madden, M. Yu, K.T. Carter, and W.M. Grady).
This material is the result of work supported in part by resources from the VA Puget Sound
Health Care System and the ColoCare Study
The UHECR dipole and quadrupole in the latest data from the original Auger and TA surface detectors
The sources of ultra-high-energy cosmic rays are still unknown, but assuming standard physics, they are expected to lie within a few hundred megaparsecs from us. Indeed, over cosmological distances cosmic rays lose energy to interactions with background photons, at a rate depending on their mass number and energy and properties of photonuclear interactions and photon backgrounds. The universe is not homogeneous at such scales, hence the distribution of the arrival directions of cosmic rays is expected to reflect the inhomogeneities in the distribution of galaxies; the shorter the energy loss lengths, the stronger the expected anisotropies. Galactic and intergalactic magnetic fields can blur and distort the picture, but the magnitudes of the largest-scale anisotropies, namely the dipole and quadrupole moments, are the most robust to their effects. Measuring them with no bias regardless of any higher-order multipoles is not possible except with full-sky coverage. In this work, we achieve this in three energy ranges (approximately 8--16 EeV, 16--32 EeV, and 32--∞ EeV) by combining surface-detector data collected at the Pierre Auger Observatory until 2020 and at the Telescope Array (TA) until 2019, before the completion of the upgrades of the arrays with new scintillator detectors. We find that the full-sky coverage achieved by combining Auger and TA data reduces the uncertainties on the north-south components of the dipole and quadrupole in half compared to Auger-only results
Joint analysis of the energy spectrum of ultra-high-energy cosmic rays measured at the Pierre Auger Observatory and the Telescope Array
The measurement of the energy spectrum of ultra-high-energy cosmic rays (UHECRs) is of crucial importance to clarify their origin and acceleration mechanisms. The Pierre Auger Observatory in Argentina and the Telescope Array (TA) in the US have reported their measurements of UHECR energy spectra observed in the southern and northern hemisphere, respectively. The region of the sky accessible to both Observatories ([−15,+24] degrees in declination) can be used to cross-calibrate the two spectra.
The Auger-TA energy spectrum working group was organized in 2012 and has been working to understand the uncertainties in energy scale in both experiments, their systematic differences, and differences in the shape of the spectra. In previous works, we reported that there was an overall agreement of the energy spectra measured by the two observatories below 10 EeV while at higher energies, a remaining significant difference was observed in the common declination band. We revisit this issue to understand its origin by examining the systematic uncertainties, statistical effects, and other possibilities. We will also discuss the differences in the spectra in different declination bands and a new feature in the spectrum recently reported by the Auger Collaboration
UHECR arrival directions in the latest data from the original Auger and TA surface detectors and nearby galaxies
The distribution of ultra-high-energy cosmic-ray arrival directions appears to be nearly isotropic except for a dipole moment of order per cent. Nonetheless, at the highest energies, as the number of possible candidate sources within the propagation horizon and the magnetic deflections both shrink, smaller-scale anisotropies might be expected to emerge. On the other hand, the flux suppression reduces the statistics available for searching for such anisotropies. In this work, we consider two different lists of candidate sources: a sample of nearby starburst galaxies and the 2MRS catalog tracing stellar mass within 250 Mpc.
We combine surface-detector data collected at the Pierre Auger Observatory until 2020 and the Telescope Array until 2019, and use them to test models in which UHECRs comprise an isotropic background and a foreground originating from the candidate sources and randomly deflected by magnetic fields. The free parameters of these models are the energy threshold, the signal fraction, and the search angular scale.
We find a correlation between the arrival directions of of cosmic rays detected with by Auger or with by TA and the position of nearby starburst galaxies on a angular scale, with a 4.2σ post-trial significance, as well as a weaker correlation with the overall galaxy distribution
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