578 research outputs found
Farinha mista de mandioca com castanha-do-brasil: uma alternativa agroecolĂłgica para a Reserva Extrativista CazumbĂĄ-Iracema.
A farinha de mandioca Ă© o principal produto em importĂąncia alimentar servindo como fonte de energia e geração de renda para os agricultores familiares da AmazĂŽnia. A castanha-do-brasil Ă© uma das principais fontes de proteĂna vegetal, geração de emprego e renda para os extrativistas da AmazĂŽnia. Este trabalho teve como objetivo analisar o arranjo produtivo local da farinha mista de mandioca com castanha-do-brasil e a produtividade de mandioca em ĂĄrea de agricultores familiares na Reserva Extrativista CazumbĂĄ-Iracema, Sena Madureira-AC. Foram avaliados os critĂ©rios de dimensĂ”es econĂŽmicas, agronĂŽmicas, ambientais e sociais destes arranjos produtivos locais. O potencial produtivo da mandioca e da castanha foram avaliados atravĂ©s de ensaios de campo e entrevistas tĂ©cnicas junto Ă s famĂlias dos agricultores e extrativistas das comunidades Cuidado, NĂșcleo CazumbĂĄ e Alto CaetĂ©. O resultado desta anĂĄlise indica que existe grande potencial de desenvolvimento social e econĂŽmico de toda a RESEX, com geração e distribuição de renda
Observation of resonances consistent with pentaquark states in decays
Observations of exotic structures in the channel, that we refer to
as pentaquark-charmonium states, in decays are
presented. The data sample corresponds to an integrated luminosity of 3/fb
acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude
analysis is performed on the three-body final-state that reproduces the
two-body mass and angular distributions. To obtain a satisfactory fit of the
structures seen in the mass spectrum, it is necessary to include two
Breit-Wigner amplitudes that each describe a resonant state. The significance
of each of these resonances is more than 9 standard deviations. One has a mass
of MeV and a width of MeV, while the second
is narrower, with a mass of MeV and a width of MeV. The preferred assignments are of opposite parity, with one
state having spin 3/2 and the other 5/2.Comment: 48 pages, 18 figures including the supplementary material, v2 after
referee's comments, now 19 figure
Observation of the decay
The decay is observed in collision
data corresponding to an integrated luminosity of 3 fb recorded by the
LHCb detector at centre-of-mass energies of 7 TeV and 8 TeV. This is the first
observation of this decay channel, with a statistical significance of 15
standard deviations. The mass of the meson is measured to be
MeV/c. The branching fraction ratio
is measured to be 0.0115\,\pm\, 0.0012\, ^{+0.0005}_{-0.0009}.
In both cases, the first uncertainty is statistical and the second is
systematic. No evidence for non-resonant or decays is found.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-033.htm
Precise measurements of the properties of the B-1(5721)(0,+) and B-2*(5747)(0,+) states and observation of B-+,B-0 pi(-,+) mass structures
Invariant mass distributions of B+Ïâ and B0Ï+ combinations are investigated in order to study excited B mesons. The analysis is based on a data sample corresponding to 3.0 fbâ1 of pp collision data, recorded by the LHCb detector at centre-of-mass energies of 7 and 8 TeV. Precise measurements of the masses and widths of the B1(5721)0,+ and B2(5747)0,+ states are reported. Clear enhancements, particularly prominent at high pion transverse momentum, are seen over background in the mass range 5850-6000 MeV in both B+Ïâ and B0Ï+ combinations. The structures are consistent with the presence of four excited B mesons, labelled BJ (5840)0,+ and BJ (5960)0,+, whose masses and widths are obtained under different hypotheses for their quantum numbers
Observation of an Excited Bc+ State
Using pp collision data corresponding to an integrated luminosity of 8.5 fb-1 recorded by the LHCb experiment at center-of-mass energies of s=7, 8, and 13 TeV, the observation of an excited Bc+ state in the Bc+Ï+Ï- invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(Bc+) MeV/c2, where the last uncertainty is due to the limited knowledge of the Bc+ mass. It is consistent with expectations of the Bcâ(2S31)+ state reconstructed without the low-energy photon from the Bcâ(1S31)+âBc+Îł decay following Bcâ(2S31)+âBcâ(1S31)+Ï+Ï-. A second state is seen with a global (local) statistical significance of 2.2Ï (3.2Ï) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(Bc+) MeV/c2, and is consistent with the Bc(2S10)+ state. These mass measurements are the most precise to date
Amplitude analysis of decays
The first full amplitude analysis of with
, decays is performed with a data sample
of 3 fb of collision data collected at and TeV
with the LHCb detector. The data cannot be described by a model that contains
only excited kaon states decaying into , and four
structures are observed, each with significance over standard deviations.
The quantum numbers of these structures are determined with significance of at
least standard deviations. The lightest has mass consistent with, but width
much larger than, previous measurements of the claimed state. The
model includes significant contributions from a number of expected kaon
excitations, including the first observation of the
transition.Comment: 62 pages 26 figure
Study of decays to the final state and evidence for the decay
A study of decays is performed for the first time
using data corresponding to an integrated luminosity of 3.0
collected by the LHCb experiment in collisions at centre-of-mass energies
of and TeV. Evidence for the decay
is reported with a significance of 4.0 standard deviations, resulting in the
measurement of
to
be .
Here denotes a branching fraction while and
are the production cross-sections for and mesons.
An indication of weak annihilation is found for the region
, with a significance of
2.4 standard deviations.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-022.html,
link to supplemental material inserted in the reference
Peripheral Nervous System Genes Expressed in Central Neurons Induce Growth on Inhibitory Substrates
Trauma to the spinal cord and brain can result in irreparable loss of function. This failure of recovery is in part due to inhibition of axon regeneration by myelin and chondroitin sulfate proteoglycans (CSPGs). Peripheral nervous system (PNS) neurons exhibit increased regenerative ability compared to central nervous system neurons, even in the presence of inhibitory environments. Previously, we identified over a thousand genes differentially expressed in PNS neurons relative to CNS neurons. These genes represent intrinsic differences that may account for the PNSâs enhanced regenerative ability. Cerebellar neurons were transfected with cDNAs for each of these PNS genes to assess their ability to enhance neurite growth on inhibitory (CSPG) or permissive (laminin) substrates. Using high content analysis, we evaluated the phenotypic profile of each neuron to extract meaningful data for over 1100 genes. Several known growth associated proteins potentiated neurite growth on laminin. Most interestingly, novel genes were identified that promoted neurite growth on CSPGs (GPX3, EIF2B5, RBMX). Bioinformatic approaches also uncovered a number of novel gene families that altered neurite growth of CNS neurons
Measurement of the Z+b-jet cross-section in pp collisions at âs = 7 TeV in the forward region
The associated production of a Z boson or an off-shell photon Îł
â with a bottom
quark in the forward region is studied using proton-proton collisions at a centre-of-mass energy
of 7 TeV. The Z bosons are reconstructed in the Z/Îłâ â ”
+”
â final state from muons
with a transverse momentum larger than 20 GeV, while two transverse momentum thresholds
are considered for jets (10 GeV and 20 GeV). Both muons and jets are reconstructed
in the pseudorapidity range 2.0 < η < 4.5. The results are based on data corresponding
to 1.0 fbâ1
recorded in 2011 with the LHCb detector. The measurement of the Z+b-jet
cross-section is normalized to the Z+jet cross-section. The measured cross-sections are
Ï(Z/Îłâ
(”
+”
â) + b-jet) = 295 ± 60 (stat) ± 51 (syst) ± 10 (lumi) fb (0.1)
for pT(jet) > 10 GeV, and
Ï(Z/Îłâ
(”
+”
â) + b-jet) = 128 ± 36 (stat) ± 22 (syst) ± 5 (lumi) fb (0.2)
for pT(jet) > 20 GeV
Observation of the B0 â Ï0Ï0 decay from an amplitude analysis of B0 â (Ï+Ï-)(Ï+Ï-) decays
Proton-proton collision data recorded in 2011 and 2012 by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb-1, are analysed to search for the charmless B0âÏ0Ï0 decay. More than 600 B0â(Ï+Ï-)(Ï+Ï-) signal decays are selected and used to perform an amplitude analysis, under the assumption of no CP violation in the decay, from which the B0âÏ0Ï0 decay is observed for the first time with 7.1 standard deviations significance. The fraction of B0âÏ0Ï0 decays yielding a longitudinally polarised final state is measured to be fL=0.745-0.058+0.048(stat)±0.034(syst). The B0âÏ0Ï0 branching fraction, using the B0âÏK*(892)0 decay as reference, is also reported as B(B0âÏ0Ï0)=(0.94±0.17(stat)±0.09(syst)±0.06(BF))Ă10-6
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