1,864 research outputs found
Local Anomalies, Local Equivariant Cohomology and the Variational Bicomplex
The locality conditions for the vanishing of local anomalies in field theory
are shown to admit a geometrical interpretation in terms of local equivariant
cohomology, thus providing a method to deal with the problem of locality in the
geometrical approaches to the study of local anomalies based on the
Atiyah-Singer index theorem. The local cohomology is shown to be related to the
cohomology of jet bundles by means of the variational bicomplex theory. Using
these results and the techniques for the computation of the cohomology of
invariant variational bicomplexes in terms of relative Gel'fand-Fuks cohomology
introduced in [6], we obtain necessary and sufficient conditions for the
cancellation of local gravitational and mixed anomalies.Comment: 36 pages. The paper is divided in two part
Heavy-ion Physics at a Fixed-Target Experiment Using the LHC Proton and Lead Beams (AFTER@LHC): Feasibility Studies for Quarkonium and Drell-Yan Production
We outline the case for heavy-ion-physics studies using the multi-TeV lead
LHC beams in the fixed-target mode. After a brief contextual reminder, we
detail the possible contributions of AFTER@LHC to heavy-ion physics with a
specific emphasis on quarkonia. We then present performance simulations for a
selection of observables. These show that , and
production in heavy-ion collisions can be studied in new energy and
rapidity domains with the LHCb and ALICE detectors. We also discuss the
relevance to analyse the Drell-Yan pair production in asymmetric
nucleus-nucleus collisions to study the factorisation of the nuclear
modification of partonic densities and of further quarkonia to restore their
status of golden probes of the quark-gluon plasma formation.Comment: 18 pages, 7 figure
Feline sino-orbital fungal infection caused by aspergillus and scopulariopsis
Background: Deep fungal infections of the orbit and nasal passages causing rhinitis and ulcerative keratomycosis are uncommonly reported in cats. Hyalohyphomycetes and phaeohyphomycetes have rarely been associated with this disorder. Sino-orbital fungal diseases are emerging and more invasive than sino-nasal fungal diseases with poor response to therapy and a worse prognosis. Brachycephalic feline breeds seem to be at increased risk for development of upper respiratory fungal diseases. Diagnosis is based on the demonstration of fungal hyphae by cytology or histology and definitive confirmation by fungal culture and molecular methods. This is the first case report of a cat with clinical mixed fungal ball with Aspergillus and Scopulariopsis in Brazil. Case: A 3-year-old male Persian cat, in São José city, Santa Catarina, Brazil, was presented with exophthalmos and corneal ulcer of the left eye and protrusion, hyperemia, quemosis and fibroses of the left third eyelid. The retropulsion of the globe was negative in this eyeball and a presumptive diagnosis of a retrobulbar mass was made. The patient underwent a surgical procedure for inspection and collection of samples for bacterial and mycological culture. Culture revealed no bacterial growth, however, unique and abundant growth of Aspergillus spp. was present. A subconjunctival enucleation of the left eye was made and the mass was sent for histopathology examination. Histology showed inflammatory proliferative necrotizing pyogranulomatous reaction; with the presence of severe fungal infection evidenced by large number of hyaline septated regular and irregular mold hyphae. Molecular identification was performed using panfungal primers (ITS3-F / ITS4-R). Patient was treated with systemic itraconazole associated with amphotericin B and topical clotrimazole. A mass started to grow rapidly in the left pterygopalatine fossa and was surgically removed, but recurrence occurred seven days after. After 22 days of treatment, the animal died suddenly with a history of acute inspiratory dyspnea and cyanosis at the time prior to death. The diagnosis of sino-orbital fungal disease in the feline was based on clinical signs, mycological culture, histopathology and molecular methods. Discussion: Sino-orbital fungal diseases rare in cats and can result in significant injuries to the upper respiratory tract and eyes, sometimes resulting in enucleation and death. It seems feasible that a brachycephalic facial conformation may be an important risk factor for the development of sino-nasal fungal diseases in cats. Despite using selected drugs and eye enucleation to treat the disease, the cat developed a rapid growing oral mass that probably caused acute inspiratory dyspnea and death. Since no controlled studies exist on the treatment of feline fungal diseases, these cases are a challenge to the feline practitioner and this type of clinical manifestation should be included in the differential diagnosis of upper respiratory and ocular diseases
Caracterización de alimentos combinando reglas de decisión relaciónales y lineales. Una aplicación al aceite de oliva virgen de Málaga
The chemical compounds of a food, quantified by GC, can be used to build relational and lineal decision rules, which merged by mathematical algorithms, could allow its characterization.
The paper describes the methods applied to design and evaluate those rules, which are kept in the knowledge base of a deductive expert system, and the procedure applied to know the similarity between an unidentified sample and the food defined by the rules.
The characterization of virgin olive oil of Malaga province has been used to explain the methodology. Thus, 54 chemical compounds belonging to five different series, fatty acids, methylsterols, sterols, aliphatic and triterpernic alcohols, and aliphatic and terpenic hydrocarbons, besides a group composed by a hydroxi-aldehid-triterpenic, phytol, and erytrodiol, were identified and quantified in each of the 172 samples collected over Andalusia. Their chromatograms, which were redrawn by computers, allowed to build seventeen rules among lineal and relational ones. These relational rules (10) show linguistic interrelations, such less, great, equal, etc., among two or more chemical compounds of the same or different series. On the other hand, statistical programs of discriminant analysis allowed to get the lineal rules (7) whose coefficients were taken from each one of the series, plus a rule where they were reached in the whole set of chemical compounds.
Finally, twenty-six samples collected in different zones, provinces or countries, or in the same area but from different crops, were used to measure the performance of the methodology.Los componentes químicos de un alimento cuantificados por cromatografía gaseosa, pueden ser usados para construir reglas de decisión relaciónales y lineales que, combinadas mediante algoritmos matemáticos, podrían permitir su caracterización.
Este trabajo describe los métodos aplicados para diseñar y evaluar las reglas, que constituyen la base de conocimientos de un sistema experto deductivo, y el procedimiento usado para determinar la similitud entre una muestra desconocida y el alimento que definen las reglas.
Para explicar y desarrollar la metodología se estudia la caracterización del aceite de oliva virgen de la provincia de Málaga.
Cincuenta y cuatro parámetros químicos pertenecientes a cinco series, ácidos grasos, metil-esteroles, esteroles, alcoholes alifáticos y triterpénicos e hidrocarburos alifáticos y terpénicos, más un grupo constituido por el fitol, el eritrodiol y un hidroxi-aldehído triterpénico, se identificaron y,midieron en 172 muestras de Andalucía. Los cromatogramas recuperados por ordenador permitieron construir 17 reglas entre relaciónales y lineales. Las reglas relaciónales (10) muestran mediante expresiones lingüísticas -mayor, menor, igual, etc.- las interrelaciones existentes entre uno o más componentes químicos de la misma o diferente serie. Las reglas lineales (7), una por cada una de las series indicadas más una usando simultáneamente todos los compuestos, se obtuvieron mediante la utilización de programas estadísticos discriminantes. Finalmente, para verificar el proceso descrito se usaron veintiséis muestras, de diferentes zonas, provincias o países
Universal behavior of baryons and mesons' transverse momentum distributions in the framework of percolation of strings
In the framework of percolation of strings, we present predictions for the
and for mesons and baryons and for ratios
at LHC energies.Comment: Presented at "Heavy Ion Collisions at the LHC: last call for
predictions", Geneva Switzerland, May 14th-June 8t
Geometric Scaling in Inclusive Charm Production
We show that the cross section for inclusive charm production exhibits
geometric scaling in a large range of photon virtualities. In the HERA
kinematic domain the saturation momentum stays below the hard
scale , implying charm production probing mostly the color
transparency regime and unitarization effects being almost negligible. We
derive our results considering two saturation models which are able to describe
the DESY ep collider HERA data for the proton structure function at small
values of the Bjorken variable . A striking feature is the scaling on
above saturation limit, corroborating recent
theoretical studies.Comment: 4 pages, 2 figures. Version to be published in Physical Review
Letter
Erosão hídrica em campo nativo sob diversos manejos: perdas de água e solo e de fósforo, potássio e amônio na água de enxurrada.
Os campos nativos do sul do Brasil são utilizados para o pastejo de bovinos e ovinos. Após o verão, no início da estação fria, a fitomassa excedente do pastejo seca, sendo comum sua queima para facilitar o rebrote da pastagem na primavera. No entanto, a queima da fitomassa mineraliza nutrientes e deixa o solo descoberto, potencializando a erosão hídrica. Este trabalho teve o objetivo de quantificar as perdas totais de água e solo e os teores de P, K e NH4 + na água da enxurrada, em campo nativo sobre um Latossolo Bruno aluminoférrico típico. Foram estudados os tratamentos: campo nativo sem queima e sem adubo; campo nativo sem queima e com superfosfato triplo; campo nativo com queima e sem adubo; e campo nativo com queima e com superfosfato triplo. Sobre as parcelas, com 11 m de comprimento, na direção do declive, e 3,5 m de largura, aplicou-se uma chuva simulada com intensidade de 75 mm h-1 e duração de 3 h. A queima influenciou a erosão hídrica e as perdas de nutrientes. A queima da fitomassa do campo nativo diminuiu os tempos de início e pico da enxurrada e a infiltração de água no solo, bem como aumentou a taxa máxima de enxurrada, as perdas de água e solo por erosão hídrica e os teores e as perdas totais de P, K e NH4 + na água de enxurrada, em relação à ausência da queima. A concentração de sedimentos na enxurrada foi maior no tratamento com queima da fitomassa do que no sem queima. O maior e o menor valor da concentração de sedimentos ocorreram em menor tempo de duração do escoamento superficial no tratamento com queima do que no tratamento sem queima, contribuindo para que a perda total de solo fosse 8,9 vezes maior com a queima do que sem a queima do campo. O teor e a perda total de P na água da enxurrada foram maiores no tratamento com adubo fosfatado do que no tratamento sem adubo, tanto no tratamento com queima da fitomassa quanto no sem queima. Para o K e o NH4 +, os teores e as perdas totais foram maiores no tratamento com queima do que no sem queima. O modelo exponencial do tipo y = ae-bx ajustou-se aos teores de P, K e NH4 + na água da enxurrada, em relação ao tempo de ocorrência do escoamento superficial (p < 0,01)
Direct photons in d+Au collisions at s_(NN)**(1/2)=200GeV with STAR
Results are presented of an ongoing analysis of direct photon production in
s_(NN)=200GeV deuteron-gold collisions with the STAR experiment at RHIC. A
significant excess of direct photons is observed near mid-rapidity 0<y<1 and
found to be consistent with next-to-leading order pQCD calculations including
the contribution from fragmentation photons.Comment: 4 pages, 4 figures, HotQuarks 200
First bolometric measurement of the two neutrino double beta decay of Mo with a ZnMoO crystals array
The large statistics collected during the operation of a ZnMoO array, for
a total exposure of 1.3 kg day of Mo, allowed the first
bolometric observation of the two neutrino double beta decay of Mo. The
observed spectrum of each crystal was reconstructed taking into account the
different background contributions due to environmental radioactivity and
internal contamination. The analysis of coincidences between the crystals
allowed the assignment of constraints to the intensity of the different
background sources, resulting in a reconstruction of the measured spectrum down
to an energy of 300 keV. The half-life extracted from the data is
T= [7.15 0.37 (stat) 0.66 (syst)] 10
y.Comment: 6 pages, 2 figure, Accepted for publication in Journal of Physics G:
Nuclear and Particle Physic
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