A Lignin-Rich Extract of Giant Reed (Arundo donax L.) as a Possible Tool to Manage Soilborne Pathogens in Horticulture: A Preliminary Study on a Model Pathosystem

Finding new sustainable tools for crop protection in horticulture has become mandatory. Giant reed (Arundo donax L.) is a tall, perennial, widely diffuse lignocellulosic grass, mainly proposed for bioenergy production due to the fact of its high biomass yield and low agronomic requirements. Some studies have already highlighted antimicrobial and antifungal properties of giant reed-derived compounds. This study aimed at investigating the potential of a lignin-rich giant reed extract for crop protection. The extract, obtained by dry biomass treatment with potassium hydroxide at 120◦C, followed by neutralization, was chemically characterized. A preliminary in vitro screening among several pathogenic strains of fungi and oomycetes showed a high sensitivity by most of the soilborne pathogens to the extract; thus, an experiment was performed with the model pathosystem, Pythium ultimum–zucchini in a growth substrate composed of peat or sand. The adsorption by peat and sand of most of the lignin-derived compounds contained in the extract was also observed. The extract proved to be effective in restoring the number of healthy zucchini plantlets in the substrate infected with P. ultimum compared to the untreated control. This study highlights the potential of the lignin-rich giant reed extract to sustain crop health in horticulture

Excitonic effects in two-dimensional vibrational spectra of liquid formamide

The linear and two-dimensional infrared (2DIR) responses of the amide I vibrational mode in liquid formamide are investigated experimentally and theoretically using molecular dynamics simulations. The recent method based on the numerical integration of the Schrödinger equation is employed to calculate the 2DIR spectra. Special attention is devoted to the interplay of the structural dynamics and the excitonic nature of the amide I modes in determining the optical response of the studied system. In particular, combining experimental data, simulated spectra and analysis of the simulated atomic trajectory in terms of a transition dipole coupling model, we provide a convincing explanation of the peculiar features of the 2DIR spectra, which show a substantial increase of the antidiagonal bandwidth with increasing frequency. We point out that, at variance with liquid water, the 2DIR spectral profile of formamide is determined more by the excitonic nature of the vibrational states than by the fast structural dynamics responsible for the frequency fluctuations

Plantas fotovoltaicas: perjuicios por no evaluar convenientemente el recurso solar

La nueva ley de fomento a la generación eléctrica mediante energías renovables ha disparado el interés de numerosos actores privados y públicos. Se discuten las consecuencias que puede aparejar una mala evaluación del recurso solar, confiando exclusivamente en estimaciones satelitales o en valores medios anuales. Se puntualiza la consternación que provoca la resolución 136/2016 del Ministerio de Energía y Minería de la Nación que excluye, de hecho, a los especialistas locales en la evaluación del recurso en las licitaciones actuales de centrales de generación eléctrica que utilicen de energías renovables como fuente primaria.The promoting electricity generation through renewable energy new law has triggered the interest of many private and public actors. The consequences can rig a poor assessment of the solar resource, relying solely on satellite estimates or average annual values are discussed. Causing consternation resolution 136/2016 of the Ministry of Energy and Mining of the Nation which excludes, in fact, local specialists on resource assessment on current tenders for power plants that use renewable energy as mentioned primary sourceTema 8: Energías renovables, modelización y simulación.Facultad de Arquitectura y Urbanism

Análisis de datos de la red solarimétrica pampeana

La red  de estaciones de medición  de radiación  solar que el Grupo  de Estudios de la Radiación  Solar (GERSolar) opera en la Pampa Húmeda (Argentina) funciona hace más de dos años. Sus diez estaciones brindan datos cada diez minutos, permitiendo calcular integrales horarias y diarias de los niveles de radiación solar global en plano horizontal. Se analiza aquí el funcionamiento de la red comparando medias mensuales con datos estimados por NASA. La consistencia de los datos es evaluada usando la heliofanía medida en cada sitio y empleando correlaciones entre datos provenientes de pares de estaciones. Se estudia la relevancia que cada estación tiene en los mapas obtenidos por medio de kriging de la distribución de líneas de iso-radiación. Dicha información permite evaluar de manera cuantitativa la incidencia de cada estación, analizando la diferencia entre los mapas trazados integrándola a la red de datos o excluyéndola El mecanismo de análisis empleado puede ser útil para, eventualmente, planificar la instalación de redes de medición con similares objetivos.The solar radiation stations measuring network, opperating for Research Group of Solar Radiation (GERSolar), has in the humid Pampas Argentina is two years of operation. Ten stations provide data every ten minutes, and the hourly and daily global solar radiation integral levels in the horizontal plane. Here we analyze the correlations between the values measured by the seasons and monthly averages. These values are compared with data estimated by NASA. The consistency of the data is analyzed using heliophany and correlations between pairs of stations. We analyze the weight that each station has in the radiation isolines maps. This information enables quantitatively evaluate the importance of each station and also to determine the most appropriate sites for future facilities measuring stations. The analysis mechanism used may be useful to eventually plan to install networks measurement with similar objectives.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Plantas fotovoltaicas: perjuicios por no evaluar convenientemente el recurso solar

La nueva ley de fomento a la generación eléctrica mediante energías renovables ha disparado el interés de numerosos actores privados y públicos. Se discuten las consecuencias que puede aparejar una mala evaluación del recurso solar, confiando exclusivamente en estimaciones satelitales o en valores medios anuales. Se puntualiza la consternación que provoca la resolución 136/2016 del Ministerio de Energía y Minería de la Nación que excluye, de hecho, a los especialistas locales en la evaluación del recurso en las licitaciones actuales de centrales de generación eléctrica que utilicen de energías renovables como fuente primaria.The promoting electricity generation through renewable energy new law has triggered the interest of many private and public actors. The consequences can rig a poor assessment of the solar resource, relying solely on satellite estimates or average annual values are discussed. Causing consternation resolution 136/2016 of the Ministry of Energy and Mining of the Nation which excludes, in fact, local specialists on resource assessment on current tenders for power plants that use renewable energy as mentioned primary sourceTema 8: Energías renovables, modelización y simulación.Facultad de Arquitectura y Urbanism

Plantas fotovoltaicas: perjuicios por no evaluar convenientemente el recurso solar

La nueva ley de fomento a la generación eléctrica mediante energías renovables ha disparado el interés de numerosos actores privados y públicos. Se discuten las consecuencias que puede aparejar una mala evaluación del recurso solar, confiando exclusivamente en estimaciones satelitales o en valores medios anuales. Se puntualiza la consternación que provoca la resolución 136/2016 del Ministerio de Energía y Minería de la Nación que excluye, de hecho, a los especialistas locales en la evaluación del recurso en las licitaciones actuales de centrales de generación eléctrica que utilicen de energías renovables como fuente primaria.The promoting electricity generation through renewable energy new law has triggered the interest of many private and public actors. The consequences can rig a poor assessment of the solar resource, relying solely on satellite estimates or average annual values are discussed. Causing consternation resolution 136/2016 of the Ministry of Energy and Mining of the Nation which excludes, in fact, local specialists on resource assessment on current tenders for power plants that use renewable energy as mentioned primary sourceTema 8: Energías renovables, modelización y simulación.Facultad de Arquitectura y Urbanism

Acoustic complexity indices reveal the acoustic communities of the old-growth Mediterranean forest of Sasso Fratino Integral Natural Reserve (Central Italy)

The Sasso Fratino Integral Natural Reserve (Central Italy), a rare example of climax Mediterranean forest, provides an extraordinary opportunity to create an important soundscape reference of old-growth forest. In this study, we describe the soundscape of three localities (Lama, Sasso 950, Sasso 1400) representative of a gradient of variety and complexity of habitats, recorded during the period 10 May to 9 June 2017. Our results reveal temporal partitioning into acoustically homogeneous periods across 24 h suggesting that soniferous species (mainly birds) adopt ecological routines in which their acoustic activity is organized according to specific transient physiological needs. We processed multi-temporal aggregates of 1, 5, 10, and 15 s recordings and calculated the Acoustic Signature (AS) with four new indices: Ecoacoustic Events (EE), Acoustic Signature Dissimilarity (ASD), and their fractal dimensions (DEE and DASD), derived from the Acoustic Complexity Index (ACI). The use of the EE and ASD greatly improved the AS interpretation, adding further details such as the emergence of a clear sequence of patterns consistent with the daily evolution of the overall soundscape. DEE and DASD confirm the patterns observed using the AS, but provide more clarity and detail about the great acoustic complexity that exists across temporal scales in this old-growth forest. The temporal turnover of different acoustic communities occurs as a result of a gradual shift of different homogenous acoustic properties. We conclude that soniferous species use distinct, species-specific temporal resolutions according to their physiological and ecological needs and that the fractal approach used here provides a novel tool to overcome the difficulties associated with describing multi-temporal acoustic patterns