Advanced search


Knowledge area




95 results, page 1 of 10

Histone deacetylase HDA-2 regulates Trichoderma atroviride growth, conidiation, blue light perception, and oxidative stress responses

MACARIO OSORIO CONCEPCION GEMA ROSA CRISTOBAL MONDRAGON BRAULIO GUTIERREZ MEDINA J SERGIO CASAS FLORES (2017)

"Fungal blue-light photoreceptors have been proposed as integrators of light and oxidative stress. However, additional elements participating in the integrative pathway remain to be identified. In Trichoderma atroviride, the blue-light regulator (BLR) proteins BLR-1 and -2 are known to regulate gene transcription, mycelial growth, and asexual development upon illumination, and recent global transcriptional analysis revealed that the histone deacetylase-encoding gene hda-2 is induced by light. Here, by assessing responses to stimuli in wild-type and Δhda-2 backgrounds, we evaluate the role of HDA-2 in the regulation of genes responsive to light and oxidative stress. Δhda-2 strains present reduced growth, misregulation of the con-1 gene, and absence of conidia in response to light and mechanical injury. We found that the expression of hda-2 is BLR-1 dependent and HDA-2 in turn is essential for the transcription of early and late light-responsive genes that include blr-1, indicating a regulatory feedback loop. When subjected to reactive oxygen species (ROS), Δhda-2 mutants display high sensitivity whereas Δblr strains exhibit the opposite phenotype. Consistently, in the presence of ROS, ROS-related genes show high transcription levels in wild-type and Δblr strains but misregulation in Δhda-2 mutants. Finally, chromatin immunoprecipitations of histone H3 acetylated at Lys9/Lys14 on cat-3 and gst-1 promoters display low accumulation of H3K9K14ac in Δblr and Δhda-2 strains, suggesting indirect regulation of ROS-related genes by HDA-2. Our results point to a mutual dependence between HDA-2 and BLR proteins and reveal the role of these proteins in an intricate gene regulation landscape in response to blue light and ROS."

Article

Trichoderma Blue light Oxidative stress BLR proteins Histone acetylation Histone deacetylases HDA-2 Hos2p CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

META: A suite of sas programs to analyze multienvironment breeding trials

Mateo Vargas Hernández Gregorio Alvarado Gary Atlin Ky Mathews Jose Crossa (2013)

Multi-environment trials (METs) enable the evaluation of the same genotypes in a variety of environments and management conditions. We present here META (Multi Environment Trial Analysis), a suite of 31 SAS programs that analyze METs with complete or incomplete block designs, with or without adjustment by a covariate. The entire program is run through a graphical user interface. The program can produce boxplots or histograms for all traits, as well as univariate statistics. It also calculates Best Linear Unbiased Estimators (BLUEs) and Best Linear Unbiased Predictors (BLUPs) for the main response variable and BLUEs for all other traits. For all traits it calculates variance components by Restricted Maximum Likelihood (REML), Least Significant Differences (LSD), Coefficient of Variation (CV), and broad-sense heritability using PROC MIXED. The program can analyze each location separately, combine the analysis by management conditions, or combine all locations. The flexibility and simplicity of use of this program makes it a valuable tool for the analysis of METs in breeding and agronomy. The META program can be used by researcher knowing few principles of SAS.

Article

Multi-environment trial SAS BLUE BLUP CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

META: A suite of sas programs to analyze multienvironment breeding trials

Jose Crossa (2013)

Multi-environment trials (METs) enable the evaluation of the same genotypes in a variety of environments and management conditions. We present here META (Multi Environment Trial Analysis), a suite of 31 SAS programs that analyze METs with complete or incomplete block designs, with or without adjustment by a covariate. The entire program is run through a graphical user interface. The program can produce boxplots or histograms for all traits, as well as univariate statistics. It also calculates Best Linear Unbiased Estimators (BLUEs) and Best Linear Unbiased Predictors (BLUPs) for the main response variable and BLUEs for all other traits. For all traits it calculates variance components by Restricted Maximum Likelihood (REML), Least Significant Differences (LSD), Coefficient of Variation (CV), and broad-sense heritability using PROC MIXED. The program can analyze each location separately, combine the analysis by management conditions, or combine all locations. The flexibility and simplicity of use of this program makes it a valuable tool for the analysis of METs in breeding and agronomy. The META program can be used by researcher knowing few principles of SAS.

Article

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Multi-environment trial SAS BLUE BLUP

Classical harmonic oscillator with Dirac-like parameters and possible applications

HARET CODRATIAN ROSU OCTAVIO CORNEJO PEREZ ROMAN LOPEZ SANDOVAL (2004)

"We obtain a class of parametric oscillation modes that we call K-modes with damping and absorption that are connected to the classical harmonic oscillator modes through the “supersymmetric” one-dimensional matrix procedure similar to relationships of the same type between Dirac and Schr¨odinger equations in particle physics. When a single coupling parameter, denoted by K, is used, it characterizes both the damping and the dissipative features of thesemodes. Generalizations to severalK parameters are also possible and lead to analytical results. If the problem is passed to the physical optics (and/or acoustics) context by switching from the oscillator equation to the corresponding Helmholtz equation, one may hope to detect the K-modes as waveguide modes of specially designed waveguides and/or cavities."

Article

Quantum-mechanics Supersymmetry Equation Diffraction Modes Light CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA

Effects of Colored Light on Growth and Nutritional Composition of Tilapia, and Biofloc as a Food Source

CARLOS ALBERTO OLVERA OLVERA (2020)

Light stimulation and biofloc technology can be combined to improve the efficiency and

sustainability of tilapia production. A 73-day pilot experiment was conducted to investigate the

effect of colored light on growth rates and nutritional composition of the Nile tilapia fingerlings

(Oreochromis niloticus) in biofloc systems. The effect of colored light on the nutritional composition of

bioflocs as a food source for fish was measured. Three groups were illuminated in addition to natural

sunlight with colored light using RGB light emitting diodes (LEDs) with peak wavelengths ( ) of

627.27 nm for red (R), 513.33 nm for green (G), and 451.67 nm for blue (B) light. LED light intensity

was constant (0.832 mW/cm2), and had an 18-h photoperiod of light per day throughout the study.

The control group was illuminated only with natural sunlight (natural). Tilapia had an average initial

weight of 0.242 g. There was a significant effect of colored light on tilapia growth and composition.

The R group showed the best growth rate, highest survival, and highest lipid content. The B group

showed homogeneous growth with the lowest growth rate and lipid content, but the highest protein

level. On the other hand, the biofloc composition was influenced by the green light in the highest

content of lipids, protein, and nitrogen-free extract.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA food science sustainable aquaculture fish production LEDs Light Color

Effect of the RGB Wavelengths of LED Light on Growth Rates of Nile Tilapia Fry in Biofloc Technology (BFT) Systems

DANIELA PAOLA LOPEZ BETANCUR (2019)

This research evaluates the effect of wavelengths of the light on growth rates of Nile tilapia fry in

the order of improving sustainability in aquaculture production. For this purpose, four tanks of water with

tilapias were studied. Three tanks were illuminated with LED lamps each one with monochromatic peak

wavelengths (𝜆): Blue light (BL) tank with 𝜆 = 451.67 nm, Green light (GL) with 𝜆 = 513.33 nm and Red

light (RL) tank with 𝜆 = 627.27 nm. All tanks were illuminated with a light intensity of 0.832 𝑚𝑊⁄𝑐𝑚2,

and they had a photoperiod of 18L:6D throughout the study. Besides, the fourth tank was illuminated only

by Natural light (NL) tank, which had the function of witness tank. Each treatment included the fourth, were

randomly assigned to 150L tanks that were stocked with 122 Nile tilapia fry. The Nile tilapia fry had an

initial average weight of 0.24 ± 0.01 𝑔, and were grown for 73 days. The average final weight for BL, GL, RL

and NL treatments were 15.54 g, 16.84 g, 17.27 g and 16.22 g, respectively. The results suggest that Nile

tilapia fry was positively influenced by the red light wavelength, which was represented in the greatest mass

gain.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Article

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Aquaculture, color, LEDs, light, tilapia.

SYNTHESIS, CHARACTERIZATION AND EVALUATION OF BARIUM AND MAGNESIUM ALUMINATES SINGLE DOPED WITH NEODYMIUM OR TANTALUM IN PHOTOCATALYTIC DYE DEGRADATION

Takawira Mumanga (2017)

"This work presents synthesized Barium and Magnesium aluminates as hosts and doped with Neodymium or Tantalum. The materials were prepared by combustion synthesis and calcined in either air oxidizing atmosphere or graphite vapor reductive atmosphere. They were evaluated as photocatalysts in the degradation of 15 ppm methylene blue by the use of a solar simulator. Characterization of these materials was done by X-ray Diffraction, Scanning Electron Microscopy, UV-VIS Spectroscopy, Luminescence Spectroscopy and Electrochemical Impedance Spectroscopy. Active redox species were investigated for their degree of participation in the photocatalytic process. The air calcined barium aluminate doped with the least concentration of neodymium was found to be the best photocatalyst in the degradation of methylene blue and a potential candidate for active oxidation processes (AOPs)."

Master thesis

Photocatalytic dye degradation Nanoparticles Methylene blue X-ray diffraction Scanning electron microscopy UV-VIS spectroscopy Luminescence spectroscopy Electrochemical impedance spectroscopy Active species CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA DEL ESTADO SÓLIDO FÍSICA DEL ESTADO SÓLIDO. ESPECTROSCOPÍA DE SÓLIDOS FÍSICA DEL ESTADO SÓLIDO. ESPECTROSCOPÍA DE SÓLIDOS

Caracterización morfológica y molecular de aislamientos de Penicillium sp obtenidos de frutos de manzana (Malus x domestica Borkh) en México y pruebas de agresividad

OMAR HERNANDEZ ROMERO (2014)

Tesis (Maestría en Ciencias, especialista en Entomología y Acarología).- Colegio de Postgraduados, 2014.

Según FAO-SAGARPA la manzana es de los productos más cultivados en el mundo; en México para 2012 se tuvo una producción de 375,044.9 ton de una superficie de 58, 451.25 ha y un promedio de rendimiento de 6.42 ton.ha-1; logrando con ello un valor de la producción de 3,008.86 millones de pesos. El estado de Chihuahua tiene la mayor área cosechada para este año con 25, 123 has. Durante el almacenamiento postcosecha de la manzana ocurren pérdidas debidas a hongos, de los cuales más de 80% son atribuidas a la pudrición azul (Penicillium expansum Link). La identificación de estas especies con base a las características morfológicas es imprecisa pues hay variación entre los aislados de una misma especie. Las técnicas moleculares basadas en el análisis de ADN son muy específicas y sensibles. En esta trabajo 118 aislamientos de Penicillium sp. provenientes de Chihuahua fueron colectados en el año 2013. La caracterización molecular de 25 de estos cultivos se realizó mediante PCR-ITS, se secuenció el producto de PCR y se confirmó a Penicillium expansum. Para la caracterización morfológica se utilizaron los medios de cultivo Potato-Dextrose-Agar (PDA) y Malta-Extracto de malta (MEA). Las colonias presentaron diversidad de formas, colores y tamaños en ambos medios. Hubo también diversidad en la longitud y formas del conidióforo, fialide, métula, y conidios y hubo traslape intra y interespecífico. La agresividad de 25 cultivos monospóricos se midió en base al diámetro de las lesiones desarrolladas en frutos de manzana var Golden Delicius, desde los 2 hasta los 10 días después de la inoculación. Solo 12 de los 25 aislados de Penicillium expansum presentaron síntomas de pudrición blanda, acuosa, color pardo claro. En la superficie aparece primero un moho blanco que luego se torna verde-azulado. Se confirmó a P. expansum como la especie más agresiva en Chihuahua, México. _______________ MOLECULAR AND MORPHOLOGICAL CHARACTERIZATION OF ISOLATION OF Penicillium sp., OBTEINED FROM APPLE FRUITS (Malus x domestica Borkh) IN MEXICO, AND AGGRESSIVENESS TESTS. ABSTRACT: According to FAO-SAGARPA, apple is one of the most cultivated fruit in the world. By 2012, there were 375,044.9 ton production in Mexico; it was cultivated in 58,451.25 ha with an average yield of 6.42 ton ha-1. As a result, the production value achieved 3,008.86 pesos millions. The Chihuahua State has the most harvested area in this year with 25,123 ha. There are losses due to fungi during the post-harvest apple storage. Most of the 80% losses are attributed to blue rot (Penicillium expansum Link). The identification of these species based on morphological characteristics is imprecise because there is a variation among isolated organisms of the same species. Molecular techniques based on DNA analysis are so specific and sensitive. In this document, 118 isolates of Penicillium sp., were collected from Chihuahua State in 2013. The molecular characterization of these 25 samples, was carried out by PCR-ITS. The PCR product was sequenced and confirmed as Penicillium expansum. To morphological characterization, were used Papa-Dextrosa-Agar (PDA) and Malt Extract-Agar (MEA); both of them, colonies showed diversity of shapes, colors and sizes. There was diversity in length and shape of conidiophore, fialide, metula, and conidia. There was overlap intra and interspecific, too. The aggressiveness of 25 monosporic samples was measured based on the diameter of the lesions developed in Golden Delicious apple fruits, in a period of 2 to 10 days after inoculation. Only 12 of 25 Penicillium expansum isolates, showed: soft rot, watery, and a light brown color. First, there appears a white mold on surface, and then it turns blue-green. P. expansum was confirmed as the most aggressive species in Chihuahua State, Mexico.

Master thesis

Penicillium expansum Pudrición azul Postcosecha Medios de cultivo PCR Blue rot Post-harvest Culture media Entomología y Acarología Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Evaluación de la terapia fotodinámica en líneas celulares de cáncer de mama con los fotosensibilizadores azul de metileno y rosa de bengala

Juan Carlos Atenco Cuautle (2019)

La terapia fotodinámica es un desarrollo biofotónico que busca ser una alternativa a tratamientos tradicionales de diferentes enfermedades, por ejemplo, el cáncer, y consiste en el aprovechamiento biológico de daño oxidativo en zonas específicas causado por un proceso fotodinámico. En este trabajo se exponen los resultados obtenidos al someter las líneas celulares de cáncer de mama MDA-MB-231 y T47D, del tipo triple negativo y tipo luminal correspondientemente, a terapia fotodinámica con los fotosensibilizadores azul de metileno y rosa de bengala, variando la densidad de radiación y la concentración de fotosensibilizador, encontrando que la viabilidad celular disminuye conforme ambos parámetros incrementan, llegando a obtener los siguientes valores mínimos de viabilidad celular: 15% para la línea MDA-MB-231 y 18% para la T47D con azul de metileno, mientras que para el rosa de bengala se obtuvo 35% para la MDA-MB-231 y 30% para la T47D.

Master thesis

Photodynamic therapy Methylene blue Rose flare Breast cancer CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Seasonal Precipitation Legacy Effects Determine the Carbon Balance of a Semiarid Grassland

JOSUE DELGADO BALBUENA JOSE TULIO ARREDONDO MORENO Henry W. Loescher Luis Felipe Pineda Martínez JOSE NOEL CARBAJAL PEREZ Rodrigo Vargas (2019)

"Semiarid grasslands are water‐limited ecosystems where precipitation (PPT) controls the onset and duration of the growing season; however, this variable does not fully explain interannual variability of productivity at temporal scales. We examined the relationship between PPT and carbon (C) fluxes in a semiarid grassland at both seasonal and interannual scales, as well as the role of lagged effects of PPT and asymmetric sensitivities of net ecosystem carbon exchange to PPT and its components (gross ecosystem exchange [GEE] and ecosystem respiration [ER]). Six years of continuous net ecosystem C exchange data measured with the eddy covariance technique and GEE estimated with 15 years of enhanced vegetation index and the gross primary productivity of Moderate Resolution Imaging Spectroradiometer were used. The semiarid grassland was a C source and a C sink among contrasting PPT years (114 to −107 g C·m−2·year−1). At seasonal scale, PPT relationship with the 15 years of GEE derived from enhanced vegetation index and gross primary productivity was sigmoidal. Moreover, PPT legacies of the previous dry season determined the C balance of the grassland by affecting the C uptake and ecosystem respiration of the following growing season, but productivity was more sensitive to PPT changes than respiration. Models of climate change for semiarid grasslands in North America predict up to 30% reduction of winter‐spring PPT and slight summer PPT decrease. Thus, our results suggest that future changes in PPT may have a strong impact on the C uptake capacity of this ecosystem due to weakened legacy effects in summer C uptake."

"Los pastizales semiáridos son ecosistemas deficientes en agua, en donde la precipitación (PPT) controla tanto el inicio como la duración de la estación de crecimiento; a pesar de eso, la precipitación no puede explicar en su totalidad la variabilidad interanual de su productividad. En este estudio, examinamos la relación entre PPT y los flujos de carbono (C) de un pastizal semiárido a escalas estacionales e interanuales, así como el papel de efectos de legado de la precipitación y la sensibilidad asimétrica del intercambio de carbono neto del ecosistema (NEE) y sus componentes (intercambio neto del ecosistema (GEE) y respiracién del ecosistema (ER)). Se emplearon seis años de datos continuos de NEE obtenidos por medio de la técnica de flujos turbulentos covariados y GEE estimados con 15 años de índice mejorado de la vegetación así como la productividad primaria bruta derivada de las imágenes del espectro radiómetro de resolución moderada. El pastizal semiárido funcionó como un almacén o una fuente de C entre años contrastantes de precipitación (114 to –107 g C•m–2•year–1). A escalas estacionales, la relación de PPT con el GEE derivado de 15 años de índice mejorado de la vegetación, así como con la producción primaria bruta fueron de tipo sigmoidal. Además, los legados de la PPT de la temporada de estiaje definió el balance de C del pastizal en la temporada de crecimiento siguiente a través de sus efectos en la asimilación de C y respiración del ecosistema, resultando la productividad más sensible a los cambios de precipitación que la respiración. Los modelos de cambio climático para el pastizal semiárido en Norte América predicen un decremento hasta del 30% de la precipitación durante el estiaje (invierno/primavera) mientras el declive de PPT en el verano será mucho menor. De esta manera, nuestros resultados sugieren que cambios futuros de la PPT tendrán un fuerte impacto en la capacidad de asimilación de C en el pastizal semiárido, debido a un efecto de legado debilitado para la asimilación de C en el verano."

Article

Blue grama Ecosystem respiration Eddy covariance Gross ecosystem exchange Net ecosystem exchange Short‐grass steppe CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS AGRONOMÍA ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL