3,416 research outputs found
Search for exotic contributions to atmospheric neutrino oscillations
The energy spectrum of neutrino-induced upward-going muons in MACRO was
analysed in terms of relativity principles violating effects, keeping standard
mass-induced atmospheric neutrino oscillations as the dominant effect. The data
disfavor these possibilities even at a sub-dominant level; stringent 90% C.L.
limits are placed on the Lorentz invariance violation parameter at = 0 and at = 1. The limits can be re-interpreted as
bounds on the Equivalence Principle violation parameters.Comment: Presented at the 29th I.C.R.C., Pune, India (2005
Nuclear DNA contents, rDNAs, and karyotype evolution in subgenus Vicia: III. The heterogeneous section Hypechusa.
Abstract: Nuclear DNA contents, automated karyotype analyses, and sequences of internal transcribed spacers from ribosomal genes have been determined in the species belonging to section Hypechusa of the sub-genus Vicia. Karyomorphological results and phylogenetic data generated from the comparison of rDNA ( genes coding for rRNA) sequences showed that sect. Hypechusa is not monophyletic; however, some monophyletic units are apparent ( one including Vicia galeata, V. hyrcanica, V. noeana, and V. tigridis, another including V. assyriaca, V. hybrida, V. melanops, V. mollis, and V. sericocarpa), which partly correspond to morphology-based infrasectional groups. The relationships among these species and the species in sections Faba, Narbonensis, Bithynicae, and Peregrinae have been also investigated. Nuclear DNA contents, automated karyotype analyses, and sequences of internal transcribed spacers from ribosomal genes have been determined in the species belonging to section Hypechusa of the subgenus Vicia. Karyomorphological results and phylogenetic data generated from the comparison of rDNA (genes coding for rRNA) sequences showed that sect. Hypechusa is not monophyletic; however, some monophyletic units are apparent (one including Vicia galeata, V. hyrcanica, V. noeana, and V. tigridis, another including V. assyriaca, V. hybrida, V. melanops, V. mollis, and V. sericocarpa), which partly correspond to morphology-based infrasectional groups. The relationships among these species and the species in sections Faba, Narbonensis, Bithynicae, and Peregrinae have been also investigated
An infrared origin of leptonic mixing and its test at DeepCore
Fermion mixing is generally believed to be a low-energy manifestation of an
underlying theory whose energy scale is much larger than the electroweak scale.
In this paper we investigate the possibility that the parameters describing
lepton mixing actually arise from the low-energy behavior of the neutrino
interacting fields. In particular, we conjecture that the measured value of the
mixing angles for a given process depends on the number of unobservable flavor
states at the energy of the process. We provide a covariant implementation of
such conjecture, draw its consequences in a two neutrino family approximation
and compare these findings with current experimental data. Finally we show that
this infrared origin of mixing will be manifest at the Ice Cube DeepCore array,
which measures atmospheric oscillations at energies much larger than the tau
lepton mass; it will hence be experimentally tested in a short time scale.Comment: 14 pages, 1 figure; version to appear in Int.J.Mod.Phys.
Search for nuclearites with the SLIM detector
We discuss the properties of cosmic ray nuclearites, from the point of view
of their search with large nuclear track detector arrays exposed at different
altitudes, in particular with the SLIM experiment at the Chacaltaya high
altitude lab (5290 m a.s.l.). We present calculations concerning their
propagation in the Earth atmosphere and discuss their possible detection with
CR39 and Makrofol nuclear track detectors.Comment: 11 pages, 6 figure
Fokker-Planck type equations with Sobolev diffusion coefficients and BV drift coefficients
In this paper we give an affirmative answer to an open question mentioned in
[Le Bris and Lions, Comm. Partial Differential Equations 33 (2008),
1272--1317], that is, we prove the well-posedness of the Fokker-Planck type
equations with Sobolev diffusion coefficients and BV drift coefficients.Comment: 11 pages. The proof has been modifie
Monge's transport problem in the Heisenberg group
We prove the existence of solutions to Monge transport problem between two
compactly supported Borel probability measures in the Heisenberg group equipped
with its Carnot-Caratheodory distance assuming that the initial measure is
absolutely continuous with respect to the Haar measure of the group
The muonic longitudinal shower profiles at production
In this paper the longitudinal profile of muon production along the shower
axis is studied. The characteristics of this distribution is investigated for
different primary masses, zenith angles, primary energies, and different high
energy hadronic models. It is found that the shape of this distribution
displays universal features similarly to what is known for the electromagnetic
profile. The relation between the muon production distribution and the
longitudinal electromagnetic evolution is also discussed
On the dynamics of WKB wave functions whose phase are weak KAM solutions of H-J equation
In the framework of toroidal Pseudodifferential operators on the flat torus
we begin by proving the closure under
composition for the class of Weyl operators with
simbols . Subsequently, we
consider when where and we exhibit the toroidal version of the
equation for the Wigner transform of the solution of the Schr\"odinger
equation. Moreover, we prove the convergence (in a weak sense) of the Wigner
transform of the solution of the Schr\"odinger equation to the solution of the
Liouville equation on written in the measure sense.
These results are applied to the study of some WKB type wave functions in the
Sobolev space with phase functions in the class
of Lipschitz continuous weak KAM solutions (of positive and negative type) of
the Hamilton-Jacobi equation for with , and to the study of the
backward and forward time propagation of the related Wigner measures supported
on the graph of
Early suppression of lymphoproliferative response in dogs with natural infection by Leishmania infantum.
Dogs are the domestic reservoirs of zoonotic visceral leishmaniasis caused by Leishmania
infantum. Early detection of canine infections evolving to clinically patent disease may be
important to leishmaniasis control. In this study we firstly investigated the peripheral blood
mononuclear cell (PBMC) response to leishmanial antigens and to polyclonal activators
concanavalin A, phytohemagglutinin and pokeweed mitogen, of mixed-breed dogs with natural
L. infantum infection, either in presymptomatic or in patent disease condition, compared to healthy
animals. Leishmania antigens did not induce a clear proliferative response in any of the animals
examined. Furthermore, mitogen-induced lymphocyte proliferation was found strongly reduced not
only in symptomatic, but also in presymptomatic dogs suggesting that the cell-mediated immunity
is suppressed in progressive canine leishmaniasis. To test this finding, naive Beagle dogs were
exposed to natural L. infantum infection in a highly endemic area of southern Italy. Two to 10
months after exposure all dogs were found to be infected by Leishmania, and on month 2 of
exposure they all showed a significant reduction in PBMC activation by mitogens. Our results
indicate that suppression of the lymphoproliferative response is a common occurrence in dogs
already at the beginning of an established leishmanial infection. # 1999 Elsevier Science B.V. All
rights reserved
Tumour-induced osteomalacia: 18 months of 2-weekly burosumab treatment
Summary: Tumour-induced osteomalacia (TIO) is due to an overproduction of fibroblast growth factor 23 (FGF23) by mesenchymal tumours, causing hypophosphatemia, osteomalacia and muscle weakness. TIO is usually cured by tumour resection, but neoplasms may be unidentifiable and unresectable or the patient may refuse surgery. In these cases, medical treatment with oral phosphate and calcitriol is mandatory, but it is not fully effective and it is associated with low compliance. Burosumab, a human MAB against FGF23 employed to treat X-linked hypophosphatemia (XLH), has recently been approved for TIO in the USA. Maximum burosumab dose in XLH is 90 mg administered for 2 weeks; there are no data on clinical efficacy and safety of this dose in TIO. We reported the case of a 73 years old male with multiple non-traumatic fractures, low bone mineral density, pain and reduced independence of activities of daily living. Biochemical evaluation showed hypophosphatemia, high alkaline phosphatase (ALP) and C-terminal telopeptide (CTX) and normal albumin-corrected total calcium and parathyroid hormone. Tubular phosphate reabsorption was low (80%), whereas C-terminal tail of FGF23 (cFGF23) was elevated. A 68Ga-DOTATOC PET was performed, identifying a lesion in the first left rib. The patient refused surgery; therefore, burosumab therapy was started. After 18 months of treatment (maximum dose: 60 mg administered for 2 weeks), plasma phosphate normalized and ALP levels improved (138 U/L). Patient clinical symptoms as well as pain severity and fatigue improved. Neither adverse events nor tumour progression was reported during follow-up except for a painless fracture of the second right rib. Learning points: Our case shows efficacy and safety of burosumab treatment administered every 2 weeks in a tumour-induced osteomalacia (TIO) patient. After 18 months of treatment at a maximum dose of 60 mg every 2 weeks, we found plasma phosphate normalization and ALP reduction as well as improvement in clinical symptoms and fatigue. Neither adverse events nor tumour progression was reported during follow-up, except for a painless fracture of the second right rib
- …