1,931 research outputs found
Cosmological Family Asymmetry and CP violation
We discuss how the cosmological baryon asymmetry can be achieved by the
lepton family asymmetries of heavy Majorana neutrino decays and they are
related to CP violation in neutrino oscillation, in the minimal seesaw model
with two heavy Majorana neutrinos. We derive the most general formula for CP
violation in neutrino oscillation in terms of the heavy Majorana masses and
Yukawa mass term. It is shown that the formula is very useful to classify
several models in which , and leptogenesis can be separately
realized and to see how they are connected with low energy CP violaton. To make
the models predictive, we take texture with two zeros in the Dirac neutrino
Yukawa matrix. In particular, we find some interesting cases in which CP
violation in neutrino oscillation can happen while lepton family asymmetries do
not exist at all. On the contrary, we can find , and
leptogenesis scenarios in which the cosmological CP violation and low
energy CP violation measurable via neutrino oscillations are very closely
related to each other. By determining the allowed ranges of the parameters in
the models, we predict the sizes of CP violation in neutrino oscillation and
. Finally, the leptonic unitarity triangles are reconstructed.Comment: 22 pages, 9 figures A figure caption correcte
Asymptotic analysis of the model for distribution of high-tax payers
The z-transform technique is used to investigate the model for distribution
of high-tax payers, which is proposed by two of the authors (K. Y and S. M) and
others. Our analysis shows an asymptotic power-law of this model with the
exponent -5/2 when a total ``mass'' has a certain critical value. Below the
critical value, the system exhibits an ordinary critical behavior, and scaling
relations hold. Above the threshold, numerical simulations show that a
power-law distribution coexists with a huge ``monopolized'' member. It is
argued that these behaviors are observed universally in conserved aggregation
processes, by analizing an extended model.Comment: 5pages, 3figure
Hierarchically Porous Gd3+-Doped CeO2 Nanostructures for the Remarkable Enhancement of Optical and Magnetic Properties
Rare earth ion-doped CeO2 has attracted more and more attention because of its special electrical, optical, magnetic, or catalytic properties. In this paper, a facile electrochemical deposition route was reported for the direct growth of the porous Gd-doped CeO2. The formation process of Gd-doped CeO2 composites was investigated. The obtained deposits were characterized by SEM, EDS, XRD, and XPS. The porous Gd3+- doped CeO2 (10 at% Gd) displays a typical type I adsorption isotherm and yields a large specific surface area of 135 m2/g. As Gd3+ ions were doped into CeO2 lattice, the absorption spectrum of Gd3+-doped CeO2 nanocrystals exhibited a red shift compared with porous CeO2 nanocrystals and bulk CeO2, and the luminescence of Gd3+-doped CeO2 deposits was remarkably enhanced due to the presence of more oxygen vacancies. In addition, the strong magnetic properties of Gd-doped CeO2 (10 at% Gd) were observed, which may be caused by Gd3+ ions or more oxygen defects in deposits. In addition, the catalytic activity of porous Gd-doped CeO2 toward CO oxidation was studied
Flavoured soft leptogenesis and natural values of the B term
We revisit flavour effects in soft leptogenesis relaxing the assumption of
universality for the soft supersymmetry breaking terms. We find that with
respect to the case in which the heavy sneutrinos decay with equal rates and
equal CP asymmetries for all lepton flavours, hierarchical flavour
configurations can enhance the efficiency by more than two orders of magnitude.
This translates in more than three order of magnitude with respect to the
one-flavour approximation. We verify that lepton flavour equilibration effects
related to off-diagonal soft slepton masses are ineffective for damping these
large enhancements. We show that soft leptogenesis can be successful for
unusual values of the relevant parameters, allowing for and for values of the washout parameter up to .Comment: 23 pages, 5 figures postscript, Minor changes to match the published
version in JHE
Variational Monte Carlo Study of Spin-Gapped Normal State and BCS-BEC Crossover in Two-Dimensional Attractive Hubbard Model
We study properties of normal, superconducting (SC) and CDW states for an
attractive Hubbard model on the square lattice, using a variational Monte Carlo
method. In trial wave functions, we introduce an interspinon binding factor,
indispensable to induce a spin-gap transition in the normal state, in addition
to the onsite attractive and intersite repulsive factors. It is found that, in
the normal state, as the interaction strength increases, a first-order
spin-gap transition arises at (: band width) from a
Fermi liquid to a spin-gapped state, which is conductive through hopping of
doublons. In the SC state, we confirm by analysis of various quantities that
the mechanism of superconductivity undergoes a smooth crossover at around
|U_{\ma{co}}|\sim |U_{\rm c}| from a BCS type to a Bose-Einstein condensation
(BEC) type, as increases. For |U|<|U_{\ma{co}}|, quantities such as
the condensation energy, a SC correlation function and the condensate fraction
of onsite pairs exhibit behavior of , as expected from the
BCS theory. For |U|>|U_{\ma{co}}|, quantities such as the energy gain in the
SC transition and superfluid stiffness, which is related to the cost of phase
coherence, behave as , as expected in a bosonic
scheme. In this regime, the SC transition is induced by a gain in kinetic
energy, in contrast with the BCS theory. We refer to the relevance to the
pseudogap in cuprate superconductors.Comment: 14 pages, 22 figures, submitted to Journal of the Physical Society of
Japa
Low temperature properties of the fermionic mixtures with mass imbalance in optical lattice
We study the attractive Hubbard model with mass imbalance to clarify low
temperature properties of the fermionic mixtures in the optical lattice. By
combining dynamical mean-field theory with the continuous-time quantum Monte
Carlo simulation, we discuss the competition between the superfluid and density
wave states at half filling. By calculating the energy and the order parameter
for each state, we clarify that the coexisting (supersolid) state, where the
density wave and superfluid states are degenerate, is realized in the system.
We then determine the phase diagram at finite temperatures.Comment: 5 pages, 4 figures, accepted for publication in J. Phys. Soc. Jp
MOG encephalomyelitis: international recommendations on diagnosis and antibody testing
Over the past few years, new-generation cell-based assays have demonstrated a robust association of autoantibodies to full-length human myelin oligodendrocyte glycoprotein (MOG-IgG) with (mostly recurrent) optic neuritis, myelitis and brainstem encephalitis, as well as with acute disseminated encephalomyelitis (ADEM)-like presentations. Most experts now consider MOG-IgG-associated encephalomyelitis (MOG-EM) a disease entity in its own right, immunopathogenetically distinct from both classic multiple sclerosis (MS) and aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorders (NMOSD). Owing to a substantial overlap in clinicoradiological presentation, MOG-EM was often unwittingly misdiagnosed as MS in the past. Accordingly, increasing numbers of patients with suspected or established MS are currently being tested for MOG-IgG. However, screening of large unselected cohorts for rare biomarkers can significantly reduce the positive predictive value of a test. To lessen the hazard of overdiagnosing MOG-EM, which may lead to inappropriate treatment, more selective criteria for MOG-IgG testing are urgently needed. In this paper, we propose indications for MOG-IgG testing based on expert consensus. In addition, we give a list of conditions atypical for MOG-EM (“red flags”) that should prompt physicians to challenge a positive MOG-IgG test result. Finally, we provide recommendations regarding assay methodology, specimen sampling and data interpretation
Production of manganese peroxidase by white rot fungi from potato-processing wastewater: Role of amino acids on biosynthesis
The production of manganese peroxidase (MnP) by white rot fungus strain L-25 was carried out using potato-processing wastewater and the effects of amino acids in the potato-processing wastewater was investigated. The MnP was efficiently produced from the wastewater by the addition of glucose and the maximum MnP activity linearly increased with an increase in the glucose concentration. The initial pH affected the cell growth and also the production rate of the MnP. The maximum activity and theproduction rate of the MnP using the potato-processing wastewater-based medium were higher (ca. 2.5- fold) than that of the basal medium. Moreover, amino acids in the wastewater had significant effects onthe MnP production. L-Glutamic acid, L-aspartic acid and L-serine induced the MnP secretion, on the other hand, L-phenylalanine, L-tyrosine, L-leucine and L-lysine inhibited it. The addition of L-leucine and L-lysine caused growth inhibition, while, L-phenylalanine and L-tyrosine blocked the MnP biosynthetic pathway. Ammonium ion released from the L-phenylalanine by the L-phenylalanine ammonia-lyase participated in the repression of the MnP biosynthetic pathway of the strain L-25
The environmental impact of fertilizer embodied in a wheat-to-bread supply chain
Food production and consumption cause approximately one-third of total greenhouse gas emissions, and therefore delivering food security challenges not only the capacity of our
agricultural system, but also its environmental sustainability. Knowing where and at what level environmental impacts
occur within particular food supply chains is necessary if
farmers, agri-food industries and consumers are to share
responsibility to mitigate these impacts. Here we present
an analysis of a complete supply chain for a staple of the
global diet, a loaf of bread. We obtained primary data for all
the processes involved in the farming, production and transport
systems that lead to the manufacture of a particular brand of
800 g loaf. The data were analysed using an advanced life
cycle assessment (LCA) tool, yielding metrics of environmental
impact, including greenhouse gas emissions. We show
that more than half of the environmental impact of producing
the loaf of bread arises directly from wheat cultivation, with
the use of ammonium nitrate fertilizer alone accounting for
around 40%. These findings reveal the dependency of bread
production on the unsustainable use of fertilizer and illustrate
the detail needed if the actors in the supply chain are to
assume shared responsibility for achieving sustainable
food production
Functional analysis of recombinant B beta 15C and B beta 15A fibrinogens demonstrates that B beta 15G residue plays important roles in FPB release and in lateral aggregation of protofibrils
The definitive version is available at www.blackwell-synergy.com.ArticleJOURNAL OF THROMBOSIS AND HAEMOSTASIS. 3(5): 983-990 (2005)journal articl
- …
