17,062 research outputs found
Explaining ATLAS and CMS Results Within the Reduced Minimal 3-3-1 model
Recently the ATLAS and CMS collaborations announced the discovery of a higgs
particle with a mass of GeV. The results are mildly consistent with
the Standard Model Higgs boson. However, the combined data from these
collaborations seem to point to an excess in the
channel. In this work we analyze under which conditions this excess may be
plausibly explained within the reduced minimal 3-3-1 model, while being
consistent with bb, WW, ZZ and channels. Moreover, we derive the
properties of the heavy neutral and the doubly charged scalars predicted by the
model. We then conclude that at a scale of a few TeV, this model provides a
good fit to the ATLAS and CMS signal strength measurements, and therefore
stands as an appealing alternative to the standard model.Comment: 23 pages, 9 figures. References adde
Biotechnology and crop protection in Brazil.
The process of modernization of Brazilian agriculture aimed at increasing the productivity in response to the high demand for agricultural products in the world market and it was based on the intensive use of inputs such as agrochemicals, intense mechanisation and breeding of new varieties. Among these, pesticides were incorporated in almost all production systems. Over reliance on pesticide use has produced many negative effects on both biotic and abiotic components of the environment, generating chemical contamination of soil and water, decrease in biological diversity of agroecosystems, disruption of natural cycles, pest resistance, intoxication of growers, among others. The consumption of pesticides in Brazil was 151.8 thousand tonnes in 1989, and today the country is the fifth world market of these products. The use of pesticides increased from 16 thousand tonnes (a.i.) in 1964 to 60.2 thousand tonnes in 1991, while the area planted to crops grew from 28.4 to 50.0 million ha in the same period. This means an increase of 276.2% in consumption of pesticides compared to an increase of 76% in planted area. Even with this large increase in the use of pesticides, the losses caused by pests have not been significantly reduced, and the net gain in crop productivity has been low. On the other hand, problems with food contamination, environmental degradation of growers have considerably mounted. It is possible to define two classes of crops regarding intense use of pesticides. One is represented by those crops that occupy large areas, and therefore contribute to a large amont of pesticides used for pest control in a country basis. The other class comprises crops that require large amounts of pesticides per unit of area, but not necessarily represent large amounts of pesticides used coutry-wide. Based on the classes proposed, citrus, soybean and sugarcane stand as crops with a nationally great consumption of pesticides, while tomato, potato and citrus are important as intensive users of pesticides. In this paper the biotechnologies in use, the biotechnologies in advanced stages of development, the main constraints to the development and use of biotechnlology and the impact of pesticed on the environment are discussed
Qualidade químico-bromatológica do feno de Cornichão cv. Estanzuela Ganador, cortado em três estádios vegetativos.
bitstream/item/31628/1/Comunicado96.pd
Rendimento de forragem e composição bromatológica de quatro leguminosas de estação fria.
bitstream/item/31666/1/comunicado78.pd
Predadores e parasitoides associados a entomofauna presente em fezes bovinas em areas de pastagens de Campo Grande, MS.
bitstream/item/132423/1/COT-58.pdf.pdfCNPGC
Combining type I and type II seesaw mechanisms in the minimal 3-3-1 model
The minimal 3-3-1 model is perturbative until energies around 4-5TeV, posing
a challenge to generate neutrino masses at eV scale, mainly if one aims to take
advantage of the seesaw mechanism. As a means to circumvent this problem we
propose a modification of the model such that it accommodates the type I and
type II seesaw mechanisms altogether. We show that the conjunction of both
mechanisms yield a neutrino mass expression suppressed by a high power of the
cutoff scale, , in its denominator. With such a suppression term we
naturally obtain neutrino masses at eV scale when is around few TeV. We
also investigate the size of lepton flavor violation through the process .Comment: about 15 pages, no figure
Avaliação químico-bromatológica da silagem pré-secada de Capim Nilo (Acroceras Macrum), cortado em três idades de corte e três tempos de emurchecimento.
bitstream/item/31627/1/Comunicado95.pd
Uso de habitats e movimentos migratórios por Pseudis platensis (ANURA: HYLIDAE) no Pantanal de Nhecolândia.
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