En la interfaz entre la historia intelectual y la sociología de la educación, el artículo aborda los usos de Antonio Gramsci efectuados por la argentina Justa Ezpeleta y la mexicana Elsie Rockwell en ...los años 70 y 80 en el marco de la estructuración de una etnográfica educativa crítica desde el Departamento de Investigaciones Educativas (DIE), Distrito Federal (México).
Durante los años 60/70, en un contexto signado por la radicalización política y teórica, se dirimió la formación académica de Rockwell y Ezpeleta. Tal contexto les permitió un acercamiento creativo al paradigma crítico y a innovadoras experiencias educativas. Ante la irrupción del golpe cívico militar de 1976 en Argentina, Ezpeleta buscará refugio en el Distrito Federal y encontrará en el DIE su lugar de trabajo. Rockwell trabajaba en la institución desde 1973, comprometida en la elaboración y seguimiento de libros de textos. Será el DIE el espacio de encuentro entre Ezpeleta y Rockwell, donde desplegarán una singular línea de investigación: la etnografía educativa crítica. Si bien esta contaba con antecedentes, las autoras establecieron una perspectiva original. Entre sus referentes teóricos, sobresalió el pensamiento de Gramsci, de amplia circulación política y académica durante los 70 y 80 en México. El artículo considera que, en la construcción de la etnografía educativa, los escritos gramscianos fueron empleados en cuatro niveles para: (a) fundamentar la perspectiva epistemológica; (b) dilucidar la historicidad del vínculo entre Estado, sociedad civil e institución escolar; (c) analizar las presencias cotidianas de las clases subalternas en la escuela; (d) cimentar un proyecto político educativo basado en la autonomía y el protagonismo popular.
Si bien la recepción de Gramsci en México durante los años 70 y 80 está siendo crecientemente indagada, el plano educativo constituye una vacancia. El artículo expone resultados producidos a través de estrategias y técnicas metodológicas de corte cualitativo.
This paper presents a current controller based on a stationary reference frame implementation of an integrator in the synchronous reference frame called here reduced order generalized integrator ...(ROGI), suitable for three-phase distributed generation systems. The proposed controller is compared with the traditional second-order generalized integrator (SOGI)-based current controller. It is confirmed that, in normal operation conditions, both controllers have similar performance, requiring the ROGI-based controller much less computational burden than the SOGI counterpart. The proposed controller injects sinusoidal currents synchronized with the grid voltage, without requiring any dedicated synchronization algorithm. Three different current injection strategies are realizable with the same controller structure: balanced current injection, constant instantaneous active power injection, and maximum instantaneous active power injection. A state-variable-based control methodology in the discrete-time domain is presented. It ensures the stability and performance of the closed-loop system, even for high-order controllers and large digital signal processor processing delay. Moreover, it is confirmed that the proposed controller works satisfactorily even on faulty grid conditions.
DNA cytosine methylation, an epigenetic mechanism involved in gene regulation and genome stability, remains poorly understood in terms of its role under changing environmental conditions. Previous ...research using methylation-sensitive amplified polymorphism (MSAP) markers in a Vitis vinifera L. cv. Malbec clone showed vineyard-specific DNA methylation polymorphism, but no change in overall methylation levels. To complement these findings, the present study investigates the intra-seasonal epigenetic dynamics between genetically identical plants grown in different vineyards through a transplanting experiment. Cuttings of the same clone, showing differential methylation patterns imposed by the vineyard of origin (Agrelo and Gualtallary), were cultivated in a common vineyard (Lunlunta). Using high-performance liquid chromatography-ultraviolet detection, the quantification of global DNA 5-methylcytosine (5-mC) levels revealed relatively low overall 5-mC percentages in grapevines, with higher levels in Agrelo (5.8%) compared to Gualtallary plants (3.7%). The transplanted plants maintained the 5-mC levels differences between vineyards (9.8% vs 6.2%), which equalized in subsequent seasons (7.5% vs 7%). Additionally, the study examined 5-mC polymorphism using MSAP markers in Lunlunta transplanted plants over three seasons. The observed differences between vineyards in MSAP patterns during the initial growing season gradually diminished, suggesting a reprogramming of the hemimethylated pattern following implantation in the common vineyard. In contrast, the non-methylated pattern exhibited greater stability, indicating a potential memory effect. Overall, this study provides valuable insights into the dynamic nature of DNA methylation in grapevines under changing environmental conditions, with potential implications for crop management and breeding strategies.
•The environment plays a role in shaping the epigenetic landscape of Vitis vinifera.•Phenotypic and epigenetic dynamics was studied in a transplanting experiment.•Original differences in DNA methylation levels are lost within two years of transplantation.•Hemimethylated pattern are reprogramed after transplantation•Non-methylated pattern exhibited greater stability, indicating a potential memory.
Key message
By studying three cv. Malbec clones cultivated in two vineyards with contrasting environmental conditions, we demonstrated that DNA methylation has an important role in the phenotypic ...plasticity and that epigenetic modulation is clone-dependent.
Clonal selection and vegetative propagation determine low genetic variability in grapevine cultivars, although it is common to observe diverse phenotypes. Environmental signals may induce epigenetic changes altering gene expression and phenotype. The range of phenotypes that a genotype expresses in different environments is known as phenotypic plasticity. DNA methylation is the most studied epigenetic mechanism, but only few works evaluated this novel source of variability in grapevines. In the present study, we analyzed the effects on phenotypic traits and epigenome of three
Vitis vinifera
cv. Malbec clones cultivated in two contrasting vineyards of Mendoza, Argentina. Anonymous genome regions were analyzed using methylation-sensitive amplified polymorphism (MSAP) markers. Clone-dependent phenotypic and epigenetic variability between vineyards were found. The clone that presented the clearer MSAP differentiation between vineyards was selected and analyzed through reduced representation bisulfite sequencing. Twenty-nine differentially methylated regions between vineyards were identified and associated to genes and/or promoters. We discuss about a group of genes related to hormones homeostasis and sensing that could provide a hint of the epigenetic role in the determination of the different phenotypes observed between vineyards and conclude that DNA methylation has an important role in the phenotypic plasticity and that epigenetic modulation is clone-dependent.
Anopheles albimanus is a malaria vector in Central America, northern South America and the Caribbean. Although a public health threat, An. albimanus precopulatory mating behaviors are unknown. ...Acoustics play important roles in mosquito communication, where flight tones allow males to detect and attract potential mates. The importance of sound in precopulatory interactions has been demonstrated in Toxorhynchites brevipalpis, Aedes aegypti, Culex quinquefasciatus and Anopheles gambiae; convergence in a shared harmonic of the wing beat frequency (WBF) during courtship is thought to increase the chance of copulation. To our knowledge, An. albimanus precopulatory acoustic behaviors have not been described to date. Here, we characterized An. albimanus (i) male and female flight tones; (ii) male-female precopulatory acoustic interactions under tethered and free flight conditions; and (iii) male-male acoustic interactions during free flight.
We found significant increases in the WBFs of both sexes in free flight compared to when tethered. We observed harmonic convergence between 79% of tethered couples. In free flight, we identified a female-specific behavior that predicts mate rejection during male mating attempts: females increase their WBFs significantly faster during mate rejection compared to a successful copulation. This behavior consistently occurred during mate rejection regardless of prior mating attempts (from the same or differing male). During group flight, males of An. albimanus displayed two distinct flying behaviors: random flight and a swarm-like, patterned flight, each associated with distinct acoustic characteristics. In the transition from random to patterned flight, males converged their WBFs and significantly decreased flight area, male-male proximity and the periodicity of their trajectories.
We show that tethering of An. albimanus results in major acoustic differences compared to free flight. We identify a female-specific behavior that predicts mate rejection during male mating attempts in this species and show that male groups in free flight display distinct flying patterns with unique audio and visual characteristics. This study shows that An. albimanus display acoustic features identified in other mosquito species, further suggesting that acoustic interactions provide worthwhile targets for mosquito intervention strategies. Our results provide compelling evidence for swarming in this species and suggests that acoustic signaling is important for this behavior.
This study investigated terpene biosynthesis in basal and apical tissues of in vitro-grown plants of
Vitis vinifera
cv. Chardonnay infected or not (control) with
Phaeoacremonium parasiticum
. This ...pathogen is one of the prevalent agents involved in the grapevine “hoja de malvón” disease. The main terpene identified by gas chromatography electron impact mass spectrometry (GC-EIMS) was nerolidol, which was found in apical and basal tissues at a concentration of ca. 0.12 μg mg FW
−1
. Consistent with this, an increment in terpene synthase (TPS) activity, assessed as tritiated farnesyl pyrophosphate (
1−3
H-FPP) transformed into hexane-soluble radioactive products in infected plants, was observed. TPS activity increased in correlation with the fungal concentration. Nerolidol inhibited in vitro mycelium growth and reduced fungal growth, in a concentration dependent manner. According to our results, the response of grapevine tissues to
Pm. parasiticum
is systemic, as it can be visualized by an augment of transcript abundance of
VvPNLinNer1
. It is also characterized by an increase of de novo synthesis of TPS responsible for the biosynthesis of phytoalexin nerolidol.
Key message
This is the first report in assessing in vitro grapevines response to woody fungus by modulating the route of terpene synthesis so increasing the phytoalexin nerolidol.
This study aimed to survey the occurrence of eight grapevine viruses in commercial vineyards located in the Calchaquíes Valleys in the northwest region of Argentina. A total of 103 samples of mature ...canes of vines showing either none or some viral-like symptoms were randomly collected. The samples were tested by RT-PCR/PCR-based assays for the screening of the following viruses: Grapevine fanleaf virus (GFLV), Grapevine leafroll-associated viruses (GLRaV-1, -2, -3, -4), Grapevine virus A (GVA), Grapevine rupestris stem pitting-associated viruses (GRSPaV), and Grapevine red blotch virus (GRBV). Sixty percent of the analyzed samples showed infection with some of the analyzed viruses, except GRBV. GLRaV-3 and GFLV were the most frequent viruses, present in 34% and 21% of the positive samples, respectively. This study represents the first survey report of the presence of grapevine viruses in the region of the Calchaquíes Valleys and contributes to the knowledge to maintain the sanitary status of commercial vineyards in Argentina.
Resumen El artículo aborda el itinerario de Antonio Gramsci en el campo pedagógico italiano y latinoamericano entre 1968 y 1991, es decir, entre los movimientos de protesta del 68 y la disolución de ...la URSS. La fase más dinámica del estudio educativo del sardo en la península ocurrió entre 1968 y 1976, mientras que, en América Latina, aconteció desde mediados de los 70 hasta 1991. A modo de hipótesis, se sugiere que la crisis del marxismo, entrados los años 70, tuvo efectos dispares en sendas regiones y en el estudio pedagógico del sardo: en Italia, suscitó una retracción, pero, en América latina, intelectuales continuaron reflexionando al interior del paradigma en crisis y recurrieron a Gramsci para renovar la investigación educativa. El artículo concluye que el régimen de circulación pedagógica de Gramsci entre sendas regiones durante el período no estuvo exento de una doble condición: dinámicas centro-periferia y una lógica patriarcal.
A new monotypic genus of Theraphosidae is described from Colombia: Aguapanela Perafán & Cifuentes gen. nov. with only the type species Aguapanela arvi Perafán, Cifuentes & Estrada sp. nov., from ...Caldas and Medellin, Antioquia, Colombian Andes. The new genus differs from other theraphosid spiders mainly in the presence of stridulatory setae on the palps and legs I and II, together with the presence of type III and IV urticating setae. Males lack a tibial apophysis on leg I and have a simple palpal bulb with the subtegulum less extended than usual in Theraphosinae, elongated curved embolus, ventrally concave, and with two prolateral keels very flat and developed on the dorsal edge. The female spermathecae have two digitiform elongated and granulated seminal receptacles attached to a semicircular wide membranous base. We describe, diagnose and illustrate the new genus and give some biological remarks. Morphological, systematic and biogeographic aspects are discussed. Chromatographic and electrophoretic profiles of its venom are analyzed.
PDF
