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Graphene-based materials are highly interesting in virtue of their excellent chemical, physical and mechanical properties that make them extremely useful as privileged materials in different industrial applications. Sonochemical methods allow the production of low-defect graphene materials, which are preferred for certain uses. Graphene nanosheets (GNS) have been prepared by exfoliation of a commercial micrographite (MG) using an ultrasound probe. Both materials were characterized by common techniques such as X-ray diffraction (XRD), Transmission Electronic Microscopy (TEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). All of them revealed the formation of exfoliated graphene nanosheets with similar surface characteristics to the pristine graphite but with a decreased crystallite size and number of layers. An exhaustive study of the particle size distribution was carried out by different analytical techniques such as dynamic light scattering (DLS), nanoparticle tracking analysis (NTA) and asymmetric flow field flow fractionation (AF4). The results provided by these techniques have been compared. NTA and AF4 gave higher resolution than DLS. AF4 has shown to be a precise analytical technique for the separation of GNS of different sizes.

The active form of vitamin D3, 1α,25-dihydroxyvitamin D3 (1,25D3), regulates a number of physiological and pathological processes, including cell proliferation and differentiation. Thousands of analogues of 1,25D3 have been developed with the aim of selective effects for medical use. Here we describe the synthesis of two new unconventional vitamin D analogues bearing A-ring modifications with ortho-carborane (dicarba-o-closo-1,2-dodecaborane) units. The ligands function as agonists for VDR with similar antiproliferative activities as 1,25D3. Whereas mice treated with the analogues 4 and 5 exhibited similar hypercalcemic activities as 1,25D3, only compound 4 and 1,25D3 induced the strong activation of CYP24A1 mRNA expression but not compound 5.

Resumen: El artículo polemiza con la clave interpretativa que afirma que tras el pasaje a la clandestinidad en 1974 se dio un proceso de militarización creciente en la organización Montoneros. Para ello, sistematiza y analiza las orientaciones e iniciativas políticas y militares de Montoneros entre 1974 y 1980, en base a una hipótesis que afirma que, pese a la clandestinización, durante todo ese período se destinaron esfuerzos tanto al accionar militar como al político.

En el siguiente escrito me propongo analizar algunas dimensiones concernientes al problema de la evolución del Estado en la Argentina entre los años 1943 y 1958, con el fin de poner en evidencia la emergencia de una matriz estatal de carácter racista en la tramitación de las diferencias políticas. El trabajo consta de cuatro partes. En la primera, procuraré mostrar el surgimiento de la cuestión de las poblaciones y la gestión de lo masivo como preocupación central del Estado entre los años 1943 y 1945. En la segunda, intentaré analizar las concepciones acerca del Estado y la nación entre los años 1945 y 1955. En la tercera, analizaré algunos elementos del proyecto “des-peronizador” de la dictadura instalada en 1955 y los distintos mecanismos institucionales que se implementaron desde el Estado para soterrar de manera definitiva a la identidad peronista. Finalmente, a partir del entrecruzamiento de diversos aportes teóricos, intentaré llegar a algunas conclusiones tendientes a poner en evidencia la emergencia histórica de una forma de racismo de Estado en el país.

The central region of Argentina is known to be a source of some most extreme weather events in the world, which are partially associated with the passage of cold fronts accompanied often by extreme wind gusts. This may cause severe property damage and even loss of human life. Nevertheless, there is a lack of studies that evaluate the performance of the numerical weather prediction (NWP) models such as weather research and forecasting (WRF) model in anticipating this type of weather in the region. This study compares the performance of the operational WRF in Argentina using four combinations of various planetary boundary layer (PBL) and microphysics parameterization schemes under varied lead times in predicting an extreme wind event (gusts > 30 m s −1 ) in Central Argentina. The results demonstrate that the WRF model is capable of providing an acceptable prediction of wind speed during an extreme event. It is found that no single combination outperforms the others, although there is a slight tendency for Combination A, which utilizes the Mellor–Yamada–Janjic (MYJ) parameterization for the PBL and the Eta similarity parameterization for the surface layer, to more accurately capture the extreme wind speed. Compared with wind gust observations at five weather stations, the wind gust parameterization predicted the intensity and occurrence time of the peak wind, with an acceptable bias (time of peak < ±1 h). Analysis of grid configurations (resolutions of 4 vs 9/3/1 km) revealed that higher resolution does not imply an improvement in the wind gust forecast for this particular event. With regard to lead time, a shorter lead time does not necessarily result in more accurate forecasts. Nevertheless, it is beneficial to conduct multiple sensitivity runs in order to obtain and understand the dispersion of forecasted wind speeds.

En el número 32, enero-junio de 2107 se publicó el artículo “Apuntes para una genealogía del racismo de Estado: Argentina entre la comunidad organizada y la tiranía depuesta (1943-1958)”. Tras el resultado final de normalización y corrección de estilo —realizados dentro de apretados tiempos editoriales—, la autora Rocío Soledad Otero consideró que algunos ajustes alteraban el sentido de su mensaje. En razón de ello, a continuación incluimos las modificaciones solicitadas por la autora The article \"Notes for a genealogy of state racism: Argentina between organized community and the deposed tyranny (1943-1958)\" was published in issue 32 (January-June of 2017). After the final result of normalization and correction of style —realized within tight editorial times—, the author Rocío Soledad Otero considered pertinent to make some adjustments. As a result, we include below the modifications requested by the author.

There is a necessity to protect the quality and authenticity of herbs and spices because of the increase in the fraud and adulteration incidence during the last 30 years. There are several aspects that make herbs and spices quite vulnerable to fraud and adulteration, including their positive and desirable sensorial and health-related properties, the form in which they are sold, which is mostly powdered, and their economic relevance around the world, even in developing countries. For these reasons, sensitive, rapid, and reliable techniques are needed to verify the authenticity of these agri-food products and implement effective adulteration prevention measures. This review highlights why spices and herbs are highly valued ingredients, their economic importance, and the official quality schemes to protect their quality and authenticity. In addition to this, the type of frauds that can take place with spices and herbs have been disclosed, and the fraud incidence and an overview of scientific articles related to fraud and adulteration based on the Rapid Alert System Feed and Food (RASFF) and the Web of Science databases, respectively, during the last 30 years, is carried out here. Next, the methods used to detect adulterants in spices and herbs are reviewed, with DNA-based techniques and mainly spectroscopy and image analysis methods being the most recommended. Finally, the available adulteration prevention measurements for spices and herbs are presented, and future perspectives are also discussed.

Using beneficial microorganisms along with sustainable strategies such as agronomic biofortification offers eco-friendly alternatives to combat climate change in ecosystems like dehesas. This study analyzes the combined effects of four wild “Trichoderma” spp. isolated from Extremadura, Spain (“T. koningiopsis”, two “T. gamsii”, and “T. koningii”, with negative and positive controls) and four Zn biofortification treatments (no Zn application; soil application of 5 mg of ZnSO4·7H2O per kg of soil, labeled soil Zn; two foliar applications of 5 mL 0.5% ZnSO4·7H2O, labeled foliar Zn; and soil + foliar combination, labeled SF) on “Trifolium subterraneum” performance. The combination of “T. koningiopsis” and “T. gamsii” with foliar Zn improved plant growth by up to 34.4%. Zinc accumulation was about 30% higher when “T. gamsii” and “T. koningii” were applied with SF, and their inoculation resulted in a 2.5-fold increase in ash. “Trichoderma” spp. affected nodulation differently; both “T. gamsii” inhibited nodulation by 24%, whereas neither “T. koningiopsis” nor “T. koningii” showed differences from the controls. These results highlight the potential of combining beneficial microorganisms with biofortification strategies to address nutrient deficiencies and improve agricultural sustainability. However, the complex interactions between both factors underscore the importance of strain selection and call for further research to optimize application strategies and elucidate underlying mechanisms.

Fusarium species represent a significant threat to pasture health, necessitating the development of sustainable solutions. This study explores the potential of regionally adapted Trichoderma isolates for controlling Fusarium avenaceum and promoting plant growth in the grasslands of the Iberian Peninsula. To this end, seven Trichoderma isolates (belonging to T. koningiopsis, T. koningii and T. gamsii) were obtained from soils of Extremadura and then evaluated as potential biocontrol agents against Fusarium avenaceum. For the purposes of this evaluation, water was used as a negative control, while a commercial Trichoderma product served as a positive control. An initial in vitro evaluation revealed that six Trichoderma isolates significantly inhibited F. avenaceum in a dual culture assay, reducing pathogen growth by 18 to 49%. Additionally, two of the isolates showed antifungal potential during the evaluation of their culture filtrates. Subsequently, two greenhouse assays were conducted to assess the effects of Trichoderma isolates and the pathogen on the development of Lolium perenne. One focused on seed germination and the other on established plants. The greenhouse experiments indicated that T08 (T. koningiopsis), T14 (T. koningii), and T19 (T. gamsii) significantly improved seed germination and plant growth, even outperforming the positive control on total dry matter in pathogen-infected plants during the postemergence test. Our study highlights the potential of Trichoderma isolates, particularly T08, T14, and T19, to boost plant growth and control Fusarium avenaceum in Lolium perenne. It emphasizes the importance of in planta testing and reveals the varying effects of the isolates throughout the plant cycle.