474 research outputs found
パーティクル・ボードに関する研究 : (第6報)含脂率およびパーティクル・ディメンションが低比重ボードの材質におよぼす影響について
この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました
Principal series of finite subgroups of SU(3)
We attempt to give a complete description of the "exceptional" finite
subgroups Sigma(36x3), Sigma(72x3) and Sigma(216x3) of SU(3), with the aim to
make them amenable to model building for fermion masses and mixing. The
information on these groups which we derive contains conjugacy classes, proper
normal subgroups, irreducible representations, character tables and tensor
products of their three-dimensional irreducible representations. We show that,
for these three exceptional groups, usage of their principal series, i.e.
ascending chains of normal subgroups, greatly facilitates the computations and
illuminates the relationship between the groups. As a preparation and testing
ground for the usage of principal series, we study first the dihedral-like
groups Delta(27) and Delta(54) because both are members of the principal series
of the three groups discussed in the paper.Comment: 43 pages, no figures; typos corrected, clarifications and references
added, version matches publication in J. Phys.
Variability in coronary hemodynamics in response to ergonovine in patients with normal coronary arteries and atypical chest pain
Because an increase in coronary vascular resistance in response to ergonovine maleate has been suggested as a possible diagnostic aid for variant angina, changes were evaluated in coronary hemodynamics and serial myocardial thallium-201 perfusion scans in 15 patients without angina and with normal coronary arteries in response to ergonovine (0.05, 0.10 and 0.20 mg intravenously). For the group, heart rate-blood pressure product increased significantly (p < 0.001) without any change in coronary sinus flow, coronary vascular resistance, myocardial oxygen extraction, arterial-coronary sinus oxygen difference and lactate extraction. In 7 of 15 patients, however, coronary vascular resistance increased (mean 39%, range 11 to 75%, probability [p] < 0.001), and coronary sinus flow decreased (14%, p < 0.001), despite an increase in heart rate-blood pressure product (36%, p < 0.02). No electrocardiographic, metabolic or thallium-201 scan abnormalities occurred. Therefore, significant increases in coronary vascular resistance in response to ergonovine may occur in patients with normal coronary arteries and atypical chest pain
Towards Minimal S4 Lepton Flavor Model
We study lepton flavor models with the flavor symmetry. We construct
simple models with smaller numbers of flavon fields and free parameters, such
that we have predictions among lepton masses and mixing angles. The model with
a triplet flavon is not realistic, but we can construct realistic models
with two triplet flavons, or one triplet and one doublet flavons.Comment: 18 pages, 4 figures, references are adde
Locomotion of Pulse-Driven Microcapsule Robot on Inclined Plane
We have developed a microcapsule robot that has a smooth outer surface and is driven by inertia and friction forces. There are no protrusions to harm the soft tissue of the intestines. The microcapsule robot consists of the body mass and the inner mass. The motion of the inner mass is generated by an inducing coil. This paper describes the investigation and analysis of the microcapsule robot motion on an inclined plane. Displacement of the microcapsule robot was measured by a high-speed camera. The experimental results demonstrate that the microcapsule robot can move upwards on an inclined plane at a small angle between 0 and 15° and consumes only 4 volts. This device is advantageous for medical purposes such as drug delivery, disease diagnosis and teleoperated surgical robots
Direct and Indirect Detection of Dark Matter in D6 Flavor Symmetric Model
We study a fermionic dark matter in a non-supersymmetric extension of the
standard model with a family symmetry based on D6xZ2xZ2. In our model, the
final state of the dark matter annihilation is determined to be e+ e- by the
flavor symmetry, which is consistent with the PAMELA result. At first, we show
that our dark matter mass should be within the range of 230 GeV - 750 GeV in
the WMAP analysis combined with mu to e gamma constraint. Moreover we
simultaneously explain the experiments of direct and indirect detection, by
simply adding a gauge and D6 singlet real scalar field. In the direct detection
experiments, we show that the lighter dark matter mass ~ 230 GeV and the
lighter standard model Higgs boson ~ 115 GeV is in favor of the observed bounds
reported by CDMS II and XENON100. In the indirect detection experiments, we
explain the positron excess reported by PAMELA through the Breit-Wigner
enhancement mechanism. We also show that our model is consistent with no
antiproton excess suggested by PAMELA.Comment: 20 pages, 9 figures, 2 tables, accepted version for publication in
European Physical Journal
Unique Continuation for Schr\"odinger Evolutions, with applications to profiles of concentration and traveling waves
We prove unique continuation properties for solutions of the evolution
Schr\"odinger equation with time dependent potentials. As an application of our
method we also obtain results concerning the possible concentration profiles of
blow up solutions and the possible profiles of the traveling waves solutions of
semi-linear Schr\"odinger equations.Comment: 23 page
Studies on possibility for alleviation of lifestyle diseases by low-dose irradiation or radon inhalation
Our previous studies showed the possibility that activation of the antioxidative function alleviates various oxidative damages, which are related to lifestyle diseases. Results showed that, low-dose X-ray irradiation activated superoxide dismutase and inhibits oedema following ischaemia-reperfusion. To alleviate ischaemia-reperfusion injury with transplantation, the changes of the antioxidative function in liver graft using low-dose X-ray irradiation immediately after exenteration were examined. Results showed that liver grafts activate the antioxidative function as a result of irradiation. In addition, radon inhalation enhances the antioxidative function in some organs, and alleviates alcohol-induced oxidative damage of mouse liver. Moreover, in order to determine the most effective condition of radon inhalation, mice inhaled radon before or after carbon tetrachloride (CCl4) administration. Results showed that radon inhalation alleviates CCl4-induced hepatopathy, especially prior inhalation. It is highly possible that adequate activation of antioxidative functions induced by low-dose irradiation can contribute to preventing or reducing oxidative damages, which are related to lifestyle diseases
Fermion masses and mixing with tri-bimaximal in SO(10) with type-I seesaw
We study a class of models for tri-bimaximal neutrino mixing in SO(10) grand
unified SUSY framework. Neutrino masses arise from both type-I and type-II
seesaw mechanisms. We use dimension five operators in order to not spoil
tri-bimaximal mixing by means of type-I contribution in the neutrino sector. We
show that it is possible to fit all fermion masses and mixings including also
the recent T2K result as deviation from the tri-bimaximal.Comment: 13 pages, journal version, minor comments and reference adde
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