Faculty Scholarship
Showing 331 - 340 of 733 Items
Date: 1995-01-01
Creator: R. Balest, K. Cho, T. Ford, D. R. Johnson, K., Lingel, M. Lohner, P. Rankin, J. G. Smith, J. P. Alexander, C. Bebek, K. Berkelman, K. Bloom, T. E. Browder, D. G. Cassel, H. A. Cho, D. M. Coffman, D. S. Crowcroft, P. S. Drell, D. Dumas, R. Ehrlich, P. Gaidarev, R. S. Galik, M. Garcia-Sciveres, B. Geiser, B. Gittelman, S. W. Gray, D. L. Hartill, B. K. Heltsley, S. Henderson, C. D. Jones, S. L. Jones
Access: Open access
- We consider the decay of Υ(1S) particles produced at CESR into a photon which is observed by the CLEO detector plus particles which are not seen. These could be real particles which fall outside of our acceptance, or particles which are noninteracting. We report the results of our search fo the process Υ(1S)→γ+''unseen'' for photon energies >1 GeV, obtaining limits for the case where ''unseen'' is either a single particle or a particle-antiparticle pair. Our upper limits represent the highest sensitivity measurements for such decays to date. © 1995 The American Physical Society.
Date: 1994-12-01
Creator: D. Cinabro, T. Liu, M. Saulnier, R. Wilson, H., Yamamoto, T. Bergfeld, B. I. Eisenstein, G. Gollin, B. Ong, M. Palmer, M. Selen, J. J. Thaler, K. W. Edwards, M. Ogg, A. Bellerive, D. I. Britton, E. R.F. Hyatt, D. B. MacFarlane, P. M. Patel, B. Spaan, A. J. Sadoff, R. Ammar, P. Baringer, A. Bean, D. Besson, D. Coppage, N. Copty, R. Davis, N. Hancock, M. Kelly, S. Kotov
Access: Open access
- We have studied the leptonic decay of the γ (1S) resonance into tau pairs using the CLEO II detector. A clean sample of tau pair events is identified via events containing two charged particles where exactly one of the particles is an identified electron. We find B(γ(1S) → τ+τ-) = (2.61±0.12-0.13+0.09)%. The result is consistent with expectations from lepton universality. © 1994.
Date: 1994-03-31
Creator: F. Butler, X. Fu, G. Kalbfleisch, W. R. Ross, P., Skubic, J. Snow, P. L. Wang, M. Wood, D. N. Brown, J. Fast, R. L. McIlwain, T. Miao, D. H. Miller, M. Modesitt, D. Payne, E. I. Shibata, I. P.J. Shipsey, P. N. Wang, M. Battle, J. Ernst, Y. Kwon, S. Roberts, E. H. Thorndike, C. H. Wang, J. Dominick, M. Lambrecht, S. Sanghera, V. Shelkov, T. Skwarnicki, R. Stroynowski, I. Volobouev
Access: Open access
- Using the CLEO II detector at CESR, we have measured the ratio of branching fractions B(D+S → φl+ν) B(D+S → φπ+) = 0.54 ± 0.05 ± 0.04. We use this measurement to obtain a model dependent estimate of B(D+S → φπ+). © 1994.
Date: 1994-01-01
Creator: D. Gibaut, K. Kinoshita, B. Barish, M. Chadha, S., Chan, D. F. Cowen, G. Eigen, J. S. Miller, C. O'Grady, J. Urheim, A. J. Weinstein, D. Acosta, M. Athanas, G. Masek, H. P. Paar, J. Gronberg, R. Kutschke, S. Menary, R. J. Morrison, S. Nakanishi, H. N. Nelson, T. K. Nelson, C. Qiao, J. D. Richman, A. Ryd, H. Tajima, D. Sperka, M. S. Witherell, M. Procario, R. Balest, K. Cho
Access: Open access
- The branching fractions for the five-charged-particle decays of the τ lepton have been measured in e+e- annihilations using the CLEO II detector at the Cornell Electron Storage Ring. Assuming all charged particles to be pions, the results are B(3π-2π+0 neutrals ντ)=(0.097±0. 005±0.011)%, B(3π-2π+ντ)=(0.077±0.005 ±0.009)%, B(3π-2π+π0ντ)=(0.019±0.004±0.004) %, and B(3π-2π+2π0ντ)<0.011% at the 90% C.L. B(3π-2π-π0ντ) is measured for the first time by exclusive π0 reconstruction. The results are compared with the predictions from the partially conserved-axial-current and conserved-vector-current hypotheses assuming isospin invariance. © 1994 The American Physical Society.
Date: 1994-01-01
Creator: M. Artuso, D. He, M. Goldberg, N. Horwitz, R., Kennett, G. C. Moneti, F. Muheim, Y. Mukhin, S. Playfer, Y. Rozen, S. Stone, M. Thulasidas, G. Vasseur, G. Zhu, J. Bartelt, S. E. Csorna, Z. Egyed, V. Jain, P. Sheldon, D. S. Akerib, B. Barish, M. Chadha, S. Chan, D. F. Cowen, G. Eigen, J. S. Miller, C. O'Grady, J. Urheim, A. J. Weinstein, D. Acosta, M. Athanas
Access: Open access
- A measurement of the cross section for γγ→pp̄ is performed at two-photon center-of-mass energies between 2.00 and 3.25 GeV. These results are obtained using e+e-→e+e-pp̄ events selected from 1.31 fb-1 of data taken with the CLEO II detector. The measured cross section is in reasonable agreement with previous measurements and is in excellent agreement with recent calculations based on a diquark model. However, leading order QCD calculations performed using the Brodsky-Lepage formalism are well below the measured cross section. © 1994 The American Physical Society.
Date: 2020-03-01
Creator: Paolo Di Vecchia, Stephen G. Naculich, Rodolfo Russo, Gabriele Veneziano, Chris D., White
Access: Open access
- High-energy massless gravitational scattering in N = 8 supergravity was recently analyzed at leading level in the deflection angle, uncovering an interesting connection between exponentiation of infrared divergences in momentum space and the eikonal exponentiation in impact parameter space. Here we extend that analysis to the first non trivial sub-leading level in the deflection angle which, for massless external particles, implies going to two loops, i.e. to third post-Minkowskian (3PM) order. As in the case of the leading eikonal, we see that the factorisation of the momentum space amplitude into the exponential of the one-loop result times a finite remainder hides some basic simplicity of the impact parameter formulation. For the conservative part of the process, the explicit outcome is infrared (IR) finite, shows no logarithmic enhancement, and agrees with an old claim in pure Einstein gravity, while the dissipative part is IR divergent and should be regularized, as usual, by including soft gravitational bremsstrahlung. Finally, using recent three-loop results, we test the expectation that eikonal formulation accounts for the exponentiation of the lower-loop results in the momentum space amplitude. This passes a number of highly non-trivial tests, but appears to fail for the dissipative part of the process at all loop orders and sufficiently subleading order in ϵ, hinting at some lack of commutativity of the relevant infrared limits for each exponentiation.
Date: 2011-01-01
Creator: A. Forche, D. Abbey, T. Pisithkul, M. A. Weinzierl, T., Ringstrom, D. Bruck, K. Petersen, J. Berman
Access: Open access
- Genetic diversity is often generated during adaptation to stress, and in eukaryotes some of this diversity is thought to arise via recombination and reassortment of alleles during meiosis. Candida albicans, the most prevalent pathogen of humans, has no known meiotic cycle, and yet it is a heterozygous diploid that undergoes mitotic recombination during somatic growth. It has been shown that clinical isolates as well as strains passaged once through a mammalian host undergo increased levels of recombination. Here, we tested the hypothesis that stress conditions increase rates of mitotic recombination in C. albicans, which is measured as loss of heterozygosity (LOH) at specific loci. We show that LOH rates are elevated during in vitro exposure to oxidative stress, heat stress, and antifungal drugs. In addition, an increase in stress severity correlated well with increased LOH rates. LOH events can arise through local recombination, through homozygosis of longer tracts of chromosome arms, or by whole-chromosome homozygosis. Chromosome arm homozygosis was most prevalent in cultures grown under conventional lab conditions. Importantly, exposure to different stress conditions affected the levels of different types of LOH events, with oxidative stress causing increased recombination, while fluconazole and high temperature caused increases in events involving whole chromosomes. Thus, C. albicans generates increased amounts and different types of genetic diversity in response to a range of stress conditions, a process that we term "stress-induced LOH" that arises either by elevating rates of recombination and/or by increasing rates of chromosome missegregation. IMPORTANCE Stress-induced mutagenesis fuels the evolution of bacterial pathogens and is mainly driven by genetic changes via mitotic recombination. Little is known about this process in other organisms. Candida albicans, an opportunistic fungal pathogen, causes infections that require adaptation to different host environmental niches. We measured the rates of LOH and the types of LOH events that appeared in the absence and in the presence of physiologically relevant stresses and found that stress causes a significant increase in the rates of LOH and that this increase is proportional to the degree of stress. Furthermore, the types of LOH events that arose differed in a stress-dependent manner, indicating that eukaryotic cells generate increased genetic diversity in response to a range of stress conditions. We propose that this "stress-induced LOH" facilitates the rapid adaptation of C. albicans, which does not undergo meiosis, to changing environments within the host. © 2011 Forche et al.
Date: 2017-11-16
Creator: Lisa Mc Intosh Sundstrom, Laura A. Henry
Access: Open access
- Under what conditions do private forest governance standards influence state policy and behavior to become more oriented toward sustainability? We argue that governance schemes targeting firms may indirectly shape state behavior, even when designed to bypass state regulation. Through an examination of the Forest Stewardship Council (FSC) in Russia and Brazil, we find that the FSC has influenced domestic rhetoric, laws, and enforcement practices. FSC has had a more disruptive and consequential impact on Russia's domestic forest governance; in Brazil, earlier transnational environmental campaigns had already begun to shift domestic institutions toward sustainability. Based on interview data and textual analysis of FSC and government documents, we identify the mechanisms of indirect FSC influence on states-professionalization, civil society mobilization, firm lobbying, and international market pressure, and argue that they are likely to be activated under conditions of poor and decentralized governance, overlapping and competing regulations and high foreign market demand for exports.
Date: 2012-04-01
Creator: Larissa M. Gaias, Katri Räikkönen, Niina Komsi, Maria A. Gartstein, Philip A., Fisher, Samuel P. Putnam
Access: Open access
- Cross-cultural differences in temperament were investigated between infants (n=131, 84 Finns), children (n=653, 427 Finns), and adults (n=759, 538 Finns) from the United States of America and Finland. Participants from both cultures completed the Infant Behavior Questionnaire, Childhood Behavior Questionnaire and the Adult Temperament Questionnaire. Across all ages, Americans received higher ratings on temperamental fearfulness than Finnish individuals, and also demonstrated higher levels of other negative affects at several time points. During infancy and adulthood, Finns tended to score higher on positive affect and elements of temperamental effortful control. Gender differences consistent with prior studies emerged cross-culturally, and were found to be more pronounced in the US during childhood and in Finland during adulthood. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.