702 research outputs found
MAPEO DE LA DISTRIBUCIÓN ESPACIAL DE TRIPS (INSECTA: THYSANOPTERA) EN PARCELAS COMERCIALES DE AGUACATE VAR. HASS EN COATEPEC HARINAS ESTADO DE MÉXICO
SE ESTABLECIÓ LA DISTRIBUCIÓN ESPACIAL DE LOS TRIPS EN CULTIVO DE AGUACATE EN UNA LOCALIDAD DEL ESTADO DE MÉXICO.El presente estudio permitió conocer la distribución espacial de trips mediante mapas de densidad en tres parcelas comerciales de aguacate VarHass en Coatepec Harinas, Estado de México. Los resultados mostraron que para el periodo comprendido de julio a diciembre de 2015, la distribución espacial de trips se ajustó a modelos gaussianos en su totalidad con una superficie infestada que osciló entre el 90 y 100% mostrando undistribución espacial agregada; el efecto pepita obtenido para todos los muestreos corroboró la agregación de las poblaciones de trips y refiere umínimo error de muestreo para los doce muestreos realizados. Trabajos como este, en que se aplican métodos geoestadísticos, coadyuvan al conocimiento de los problemas fitosanitarios de los cultivos de importancia económica y a la aplicación de medidas de control (químico, biológicocultural o mecánico) dirigidas a zonas específicas de la parcela
Adherence to the physical activity guideline beyond the recommended minimum weekly amount: impacts on indicators of physical function in older adults
IntroductionThe extent to which additional health benefits of accumulating twice the minimum amount of time in moderate-to-vigorous physical activity (MVPA) affects indicators of physical function in older adults is unclear. Therefore, the aim of the present study was to assess indicators of physical function in older adults who accumulate at least 150 but less than 300 min/week of MVPA compared to those accumulating at least 300 min/week.MethodsIndicators of physical function, including handgrip strength, 5 times sit-to-stand test (5-STS), squat jump and 6-min walk test (6MWT) were assessed in a sample of 193 older men (n = 71, 67 ± 2 years), and women (n = 122, 67 ± 2 years), who all accumulated at least 150 weekly minutes of MVPA. Time in MVPA was assessed by accelerometry during 1 week and engagement in muscle strengthening activities (MSA) was assessed by self-report. Protein intake was assessed by a food-frequency-questionnaire. Participants were classified as physically active (≥150 but <300 min of MVPA per week) or as highly physically active (≥300 min of MVPA per week).ResultsFactorial analysis of variance revealed that older adults accumulating at least 300 min of MVPA per week had a significantly (p < 0.05) better 6MWT performance and overall physical function compared to the less active group. These findings remained significant after further adjustment for MSA, sex, waist circumference and protein intake. In contrast, no significant differences in indicators of muscle strength were observed between the two groups.DiscussionAdherence to twice the recommended minimum amount of weekly MVPA time is related to a better physical function, evidenced by a better walking performance compared to adherence to the minimum weekly amount of MVPA. This finding emphasizes the benefits of accumulating daily MVPA beyond the minimum recommended amount to optimize the ability to perform activities of daily living, thus reducing the burden of physical disability and related health-care costs
Distribución espacial de trips spp. (thysanoptera) y evaluación de su control mediante el depredador a Mblyseius swirskii en el cultivo de aguacate en México
SE LOGRO DETERMINAR LA DISTRIBUCIÓN ESPACIAL DE LAS POBLCIONES DE TRIPS Y SE ESTABLECIÓ LA EFICIENCIA DE Amblyseius swirskii COMO BIOCONTROLADOR.El uso de diferentes alternativas en el control de plagas y enfermedades es de gran importancia en la elaboración de programas de manejo integrado. El presente estudio se realizó con el fin de conocer la distribución espacial de trips y la efectividad del depredador Amblyseius swirskii que tiene sobre sus poblaciones en el cultivo de aguacate. Se determinó la distribución espacial de la plaga, también se determinó el semivariograma experimental y se obtuvieron los mapas de agregación de la plaga. Se determinó que existe infestación en las tres parcelas y para la mayoría de los meses al 100 por ciento, se realizó una prueba estadística para conocer si existen diferencias significativas a partir de la liberación del depredador, existe reducción de las poblaciones donde existe la liberación del depredador el cual se observa en los promedios de infestación y en los mapas de agregación de la plaga, con lo anterior conocemos la distribución de la plaga lo cual nos ayuda a implementar métodos focalizados de control integrado y obtener ahorros económicos, así como también conocemos otro método para el control del trips
Estabilidad espacial y temporal de la distribución de TRIPS en el cultivo de aguacate en el Estado de México
SE DETERMINÓ LA ESTABILIDAD ESPACIAL Y TEMPORAL DE LA DISTRIBUCIÓN DE LAS POBLACIONES DE TRIPS EN EL CULTIVO DE AGUACATE EN EL ESTADO DE MÉXICO.El uso excesivo e inadecuado de plaguicidas ha causado graves daños al ambiente y a la salud humana; por ello la utilización de nuevas técnicas que coadyuven a mitigar los impactos generados han tomado importancia durante los últimos años. De esta manera se realizan trabajos enfocados en la planeación y muestreo sistematizado de plagas, los cuales tienen como propósito proveer la información necesaria que permita el uso adecuado de plaguicidas y esto dé pie a la generación de una agricultura más sustentable. Los trips son insectos que causan graves daños en las huertas del cultivo de aguacate en el municipio de Coatepec Harinas, Estado de México, y otros estados productores de este fruto, por ello, el estudio se realizó con el objetivo de analizar la estabilidad espacio temporal de trips con el índice de SADIE y la prueba de Cramér-von Mises, así como la modelización espacial de trips. Los resultados muestran que la geoestadística y el SADIE lograron establecer patrones espaciales de trips y determinar su estabilidad espaciotemporal. En los mapas de cada muestreo pueden ser visualizados diversos centros de agregación, lo que puede poner en marcha acciones preventivas hacia determinados puntos de incidencia de trips como la aplicación de insecticidas a árboles o área de las parcelas con infestaciones mayores
Estabilidad Espacial y Temporal de la Distribución de Trips 1 en el Cultivo de Aguacate en el Estado de México
El uso excesivo e inadecuado de plaguicidas ha causado graves daños al ambiente y a la salud humana; por ello la utilización de nuevas técnicas que coadyuven a mitigar los impactos generados han tomado importancia durante los últimos años. De esta manera se realizan trabajos enfocados en la planeación y muestreo sistematizado de plagas, los cuales tienen como propósito proveer la información necesaria que permita el uso adecuado de plaguicidas y esto dé pie a la generación de una agricultura más sustentable. Los trips son insectos que causan graves daños en las huertas del cultivo de aguacate en el municipio de Coatepec Harinas, Estado de México, y otros estados productores de este fruto, por ello, el estudio se realizó con el objetivo de analizar la estabilidad espacio temporal de trips con el índice de SADIE y la prueba de Cramér-von Mises, así como la modelización espacial de trips. Los resultados muestran que la geoestadística y el SADIE lograron establecer patrones espaciales de trips y determinar su estabilidad espaciotemporal. En los mapas de cada muestreo pueden ser visualizados diversos centros de agregación, lo que puede poner en marcha acciones preventivas hacia determinados puntos de incidencia de trips como la aplicación de insecticidas a árboles o área de las parcelas con infestaciones mayores
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
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
Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
Measurements of multi-particle azimuthal correlations (cumulants) for charged
particles in p-Pb and Pb-Pb collisions are presented. They help address the
question of whether there is evidence for global, flow-like, azimuthal
correlations in the p-Pb system. Comparisons are made to measurements from the
larger Pb-Pb system, where such evidence is established. In particular, the
second harmonic two-particle cumulants are found to decrease with multiplicity,
characteristic of a dominance of few-particle correlations in p-Pb collisions.
However, when a gap is placed to suppress such correlations,
the two-particle cumulants begin to rise at high-multiplicity, indicating the
presence of global azimuthal correlations. The Pb-Pb values are higher than the
p-Pb values at similar multiplicities. In both systems, the second harmonic
four-particle cumulants exhibit a transition from positive to negative values
when the multiplicity increases. The negative values allow for a measurement of
to be made, which is found to be higher in Pb-Pb collisions at
similar multiplicities. The second harmonic six-particle cumulants are also
found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find
which is indicative of a Bessel-Gaussian
function for the distribution. For very high-multiplicity Pb-Pb
collisions, we observe that the four- and six-particle cumulants become
consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and
Pb-Pb are measured. These are found to be similar for overlapping
multiplicities, when a gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87
Charge separation relative to the reaction plane in Pb-Pb collisions at TeV
Measurements of charge dependent azimuthal correlations with the ALICE
detector at the LHC are reported for Pb-Pb collisions at TeV. Two- and three-particle charge-dependent azimuthal correlations in
the pseudo-rapidity range are presented as a function of the
collision centrality, particle separation in pseudo-rapidity, and transverse
momentum. A clear signal compatible with a charge-dependent separation relative
to the reaction plane is observed, which shows little or no collision energy
dependence when compared to measurements at RHIC energies. This provides a new
insight for understanding the nature of the charge dependent azimuthal
correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286
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