3,505 research outputs found
Time Measurement in Quantum Gravity
We discuss time measurement in quantum gravity. Using general relativity for
large distances and the uncertainty principle we find a minimum time interval
of the order of the Planck time, therefore the uncertainty in time measurment
is bounded from below.Comment: 4 pages, TAUP-2087-9
Renormalization Group and Dynamics of Supersymmetric Gauge Theories
We discuss questions related to renormalization group and to nonperturbative
aspects of non-Abelian gauge theories with N=2 and/or N=1 supersymmetry.
Results on perturbative and nonperturbative functions of these theories
are reviewed, and new mechanisms of confinement and dynamical symmetry breaking
recently found in a class of , and theories are
discussed.Comment: 13 pages, 3 figures, uses ws-p9-75x6-50.cls. Lecture given at the
Second Conference on the ERG, Rome 200
Fermions, Anomaly and Unitarity in High-Energy Electroweak Scattering
We report the "state of the art" of the problem of violation in
high-energy electroweak scatterings. Results of various analyses point toward
(though do not prove rigorously yet) the "half-suppression", i.e., that the
violating cross section remains suppressed at least by the negative
exponent of the single instanton action, at all energies. Most interesting
techniques developed in this field are reviewed. Particular attention is paid
to unitarity constraints on the anomalous cross section, and to some conceptual
problem involving the use of the optical theorem in the presence of instantons.Comment: 59 (Latex) pages (+13 postscript figures (1075 blocks) available by
e-mail request), GEF-Th-17/199
An investigation of tooth loss factors in elderly patients using panoramic radiographs
Objectives The aim of this study was to observe the dental condition in a group of elderly patients over a period of 10 years in order to clarify important risk factors. Materials and methods Participants were elderly patients (in their eighties) who took panoramic radiographs between 2015 and 2016, and for whom panoramic radiographs taken around 10 year earlier were also available. The number of remaining and lost teeth, the Eichner Index, the presence or absence of molar occlusion, the respective condition of dental pulp, dental crowns, alveolar bone resorption, as well as periapical lesions were investigated through the analysis of panoramic radiographs. Additionally, other important variables were collected from patients' medical records. From the obtained panoramic radiograph sets, the patients' dental condition was investigated, and a systematic comparison was conducted. Results The analysis of the panoramic radiographs showed that the number of remaining teeth decreased from an average of 20.8-15.5, and the percentage of patients with 20 or more teeth decreased from 69.2 to 26.9%. A factor analysis investigating tooth loss risk suggested that tooth loss was associated with the bridge, P2 or greater resorption of the alveolar bone, and apical lesions, and gender (with males having a higher risk compared to females). Conclusions Teeth showing P2 or greater alveolar bone resorption, bridge, and apical lesions on panoramic radiographs are most likely to be lost in an elderly patient's near future. Consequently, this group should be encouraged to visit their dental clinics regularly and receive comprehensive instruction on individual self-care methods
Hierarchical clustering and formation of power-law correlation in 1-dimensional self-gravitating system
The process of formation of fractal structure in one-dimensional
self-gravitating system is examined numerically. It is clarified that
structures created in small spatial scale grow up to larger scale through
clustering of clusters, and form power-law correlation.Comment: 9pages,4figure
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