29 research outputs found
CARACTERIZACIÓN MORFOLÓGICA DE FRUTO DE LA COLECCÓN ex situ DE Psidium guajava L.
Guava tree (Psidium guajava L.) is an important crop in different parts of the world, and its fruit is muchappreciated for its nutritional properties. It is considered to be native of Mesoamerica, and it has beenreported that in México it presents diversity in form of the fruit. With the purpose of taking advantageof this diversity, accessions of P. guajava were collected and an ex situ collection was established, for their characterization and conservation. From 16 states, 93 guava accessions were analyzed, as well as three introduced genotypes, based on 24 quantitative and qualitative morphological traits, through principal components. The first five components explained 60 % of the total variability, and the variables of greatest descriptive value were: those related to the size of the fruit (weight, diameter, pulp thickness); the number and weight of seeds; the shape of the fruit, color of the pulp and texture. In general, the accessions showed variability in the characteristics evaluated, which reveals the broad genetic base of the germplasm, which can be taken advantage of in the development of new varieties that satisfy demands from the consumer and from the industry for fresh fruit.El guayabo (Psidium guajava L.) es un cultivo importante en diferentes partes del mundo, y su fruto es muy apreciado por sus propiedades nutricionales. Se considera originario de Mesoamérica, y se ha reportado que en México presenta diversidad en forma del fruto. Con el propósito de aprovechar esta diversidad, se recolectaron accesiones de P. guajava logrando establecer una colección ex situ, para caracterización y conservación. Se analizaron 93 accesiones de guayabo provenientes de 16 estados, así como tres genotipos introducidos, basándose en 24 caracteres morfológicos cuantitativos y cualitativos, mediante componentes principales. Los primeros cinco componentes explicaron 60% de la variabilidad total y las variables de mayor valor descriptivo fueron: las relacionadas con el tamaño del fruto (peso, diámetros, grosor de pulpa); el número y peso de semillas; forma del fruto, color de pulpa y textura. En general, las accesiones mostraron variabilidad en las características evaluadas, lo que revela la amplia base genética del germoplasma, mismo que puede ser aprovechada en el desarrollo de nuevas variedades que satisfagan demandas del consumidor de fruta fresca y la industria
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
Measurement of charm production at central rapidity in proton-proton collisions at TeV
The -differential production cross sections of the prompt (B
feed-down subtracted) charmed mesons D, D, and D in the rapidity
range , and for transverse momentum GeV/, were
measured in proton-proton collisions at TeV with the ALICE
detector at the Large Hadron Collider. The analysis exploited the hadronic
decays DK, DK, DD, and their charge conjugates, and was performed on a
nb event sample collected in 2011 with a
minimum-bias trigger. The total charm production cross section at TeV and at 7 TeV was evaluated by extrapolating to the full phase space
the -differential production cross sections at TeV
and our previous measurements at TeV. The results were compared
to existing measurements and to perturbative-QCD calculations. The fraction of
cdbar D mesons produced in a vector state was also determined.Comment: 20 pages, 5 captioned figures, 4 tables, authors from page 15,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/307
Transverse momentum spectra of charged particles in proton-proton collisions at GeV with ALICE at the LHC
The inclusive charged particle transverse momentum distribution is measured
in proton-proton collisions at GeV at the LHC using the ALICE
detector. The measurement is performed in the central pseudorapidity region
over the transverse momentum range GeV/.
The correlation between transverse momentum and particle multiplicity is also
studied. Results are presented for inelastic (INEL) and non-single-diffractive
(NSD) events. The average transverse momentum for is (stat.) (syst.) GeV/ and
\left_{\rm NSD}=0.489\pm0.001 (stat.) (syst.)
GeV/, respectively. The data exhibit a slightly larger than measurements in wider pseudorapidity intervals. The results are
compared to simulations with the Monte Carlo event generators PYTHIA and
PHOJET.Comment: 20 pages, 8 figures, 2 tables, published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/390
Neutral pion and meson production in proton-proton collisions at TeV and TeV
The first measurements of the invariant differential cross sections of
inclusive and meson production at mid-rapidity in proton-proton
collisions at TeV and TeV are reported. The
measurement covers the ranges GeV/ and GeV/ for
these two energies, respectively. The production of mesons was measured
at TeV in the range GeV/. Next-to-Leading Order
perturbative QCD calculations, which are consistent with the spectrum
at TeV, overestimate those of and mesons at
TeV, but agree with the measured ratio at
TeV.Comment: 17 pages, 5 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/310
KK correlations in pp collisions at TeV from the LHC ALICE experiment
Identical neutral kaon pair correlations are measured in TeV pp
collisions in the ALICE experiment. One-dimensional KK correlation
functions in terms of the invariant momentum difference of kaon pairs are
formed in two multiplicity and two transverse momentum ranges. The femtoscopic
parameters for the radius and correlation strength of the kaon source are
extracted. The ft includes quantum statistics and final-state
interactions of the a/f resonance. KK correlations show an
increase in radius for increasing multiplicity and a slight decrease in radius
for increasing transverse mass, , as seen in correlations
in the pp system and in heavy-ion collisions. Transverse mass scaling is
observed between the KK and radii. Also, the frst
observation is made of the decay of the f(1525) meson into the
KK channel in pp collisions.Comment: 17 pages, 7 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/310
J/psi Production as a Function of Charged Particle Multiplicity in pp Collisions at sqrt{s} = 7 TeV
The ALICE collaboration reports the measurement of the inclusive J/psi yield
as a function of charged particle pseudorapidity density dN_{ch}/deta in pp
collisions at sqrt{s} = 7 TeV at the LHC. J/psi particles are detected for p_t
> 0, in the rapidity interval |y| < 0.9 via decay into e+e-, and in the
interval 2.5 < y < 4.0 via decay into mu+mu- pairs. An approximately linear
increase of the J/psi yields normalized to their event average
(dN_{J/psi}/dy)/ with (dN_{ch}/deta)/ is observed
in both rapidity ranges, where dN_{ch}/deta is measured within |eta| < 1 and
p_t > 0. In the highest multiplicity interval with = 24.1,
corresponding to four times the minimum bias multiplicity density, an
enhancement relative to the minimum bias J/psi yield by a factor of about 5 at
2.5 < y < 4 (8 at |y| < 0.9) is observed.Comment: Submitted to Phys. Lett.
Charged-particle multiplicity measurement in proton-proton collisions at root s=7 TeV with ALICE at LHC
The pseudorapidity density and multiplicity distribution of charged particles produced in proton-proton collisions at the LHC, at a centre-of-mass energy root s = 7 TeV, were measured in the central pseudorapidity region vertical bar eta vertical bar < 1. Comparisons are made with previous measurements at root s = 0.9 TeV and 2.36 TeV. At root s = 7 TeV, for events with at least one charged particle in |eta vertical bar| < 1, we obtain dN(ch)/d eta = 6.01 +/- 0.01(stat.)(-0.12)(+0.20) (syst.). This corresponds to an increase of 57.6%+/-0.4%(stat.)(-1.8%)(+3.6) (syst.) relative to collisions at 0.9 TeV, significantly higher than calculations from commonly used models. The multiplicity distribution at 7 TeV is described fairly well by the negative binomial distribution