6 research outputs found

    Sustratos alternativos para la producción de plántulas de tomate de cáscara (Physalis ixocarpa Brot.) en Chiapas

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    The present project aimed to evaluate the effect of different alternative substrates during the emergence and growth of Physalis ixocarpa Brot. obtained in root trays, under shadow mesh conditions. The research took place in Cintalapa, Chiapas. The substrates employed were T1 cosmopeat as master sample, T2 earthworm humus, T3 sawdust of Pinus Oocarpa and T4 compost. The treatments were stablished with a completely random design with four repetitions, sowing 50 seeds for each repetition in unicel trays. The variables of this study were analyzed by median comparison (El presente trabajo tuvo como objetivo evaluar el efecto de distintos sustratos alternativos en la emergencia y crecimiento de Physalis ixocarpa Brot. obtenidos en cepellón, bajo condiciones de malla sombra. La investigación se llevó a cabo en el municipio de Cintalapa, Chiapas. Los sustratos empleados fueron T1 cosmopeat usado como testigo, T2 humus de lombriz, T3 aserrín de Pinus oocarpa y T4 composta. Los tratamientos se establecieron bajo un diseño completamente al azar con cuatro repeticiones, sembrándose 50 semillas por cada repetición en bandejas de unicel. Las variables de estudio fueron sometidas a un análisis de comparación de medias

    Composición morfológica y rendimientos de maíces nativos sin uso de agroquímicos en Chiapas, México

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    The objective of this study was to characterize the morphological composition of five populations of native maize and estimate their yields using agricultural practices without the use of agrochemicals. The study conducted in 2021, in the municipality of Cintalapa, Chiapas, within the experimental field of the Regional Academic Center of the Antonio Narro Autonomous Agrarian University. The five populations of native maize were provided by farmers from different regions of the state, with prior informed consent. The Agricultural practices consisted of using plant extracts and potassium soap with neem extract (Azadirachta indica) to prevent and combat pests. For fertilization, Californian red earthworm (Eisenia foetida) leachate and bat guano were applied in their commercial presentation. Morphological characters were evaluated with a descriptive statistical analysis considering days to male and female flowering, plant and ear height ear length and diameter, number of rows per ear and number of kernels per row. Grain yield was estimated by the weight of the ear harvested from a random sample of 20 plants per population. Numerical differences of the studied variables were identified, which demonstrates an existing genetic diversity. The populations with the highest yields were Campeón and Olotillo, with 5.37 and 4.4 ton ha-1 (± 1.24), respectively. The data provide information to design native maize conservation strategies through agrochemical-free management.El objetivo de este estudio fue caracterizar morfológicamente cinco poblaciones de maíz nativo y estimar sus rendimientos, empleando prácticas agrícolas sin uso de agroquímicos. El estudio se realizó en el año 2021, en el municipio de Cintalapa, Chiapas, dentro del campo experimental del Centro Académico Regional de la Universidad Autónoma Agraria Antonio Narro. Las cinco poblaciones de maíz nativo fueron proporcionadas por campesinos de diferentes regiones de la entidad, con previo consentimiento informado. Las prácticas agrícolas consistieron en uso de extractos vegetales y jabón potásico con extracto de neem (Azadirachta indica) para la prevención y combate de plagas. Para la fertilización se aplicó lixiviado de lombriz roja californiana (Eisenia foetida) y guano de murciélago en su presentación comercial. Los caracteres morfológicos se evaluaron con un análisis estadístico descriptivo considerando: días de floración masculina y femenina, alturas de planta y mazorca, longitud y diámetro de la mazorca, y número de hileras por mazorca y número de granos por hilera. El rendimiento de grano se estimó mediante el peso de la mazorca cosechada de una muestra aleatoria de 20 plantas por población. Se identificaron diferencias numéricas de las variables estudiadas, lo que demuestra una diversidad genética existente. Las poblaciones que presentaron mayores rendimientos fueron Campeón y Olotillo, con 5,37 y 4,4 ton ha-1 (± 1,24), respectivamente. Los datos aportan información para diseñar estrategias de conservación de maíces nativos con manejo libre de agroquímicos

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

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    Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network

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    Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects

    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

    Ultralight vector dark matter search using data from the KAGRA O3GK run

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    Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM
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