Visibility Assessment of New Photovoltaic Power Plants in Areas with Special Landscape Value

Power plants based on renewable sources offer environmental, technical and economic advantages. Of particular importance is the reduction in greenhouse gas emissions compared to conventional power plants. Despite the advantages, people are often opposed to the construction of these facilities due to their high visual impact, particularly if they are close to places with a great cultural and/or landscape value. This paper proposes a new methodology for identifying the most suitable geographical areas for the construction of new photovoltaic (PV) power plants in zones of special scenic or cultural interest, helping to keep the environment free from the visual intrusions caused by these facilities. From several repeated analyses, the degree of visibility of the new PV plant, the potential observation time of passing visitors, considering the route they follow and their speed, and the increase in visibility of the plants when seen totally or partially with the sky as background, are determined. The result obtained is a map showing the ranking of the geographical areas based on a variable calculated in such analyses: the Global Accumulated Perception Time (GAPT). The application of this methodology can help the different agents involved in the decision-making process for the installation of new PV plant by providing them with an objective visibility criterion

Infection of Rat Osteoblasts with Junin Virus Promotes the Expression of Bone Morphogenetic Protein 6, an Osteogenic Differentiation Inducer

BACKGROUND:The arenavirus Junin virus (JUNV), causative agent of the argentine hemorrhagic fever, is able to modulate several signaling pathways involved in cell survival and multiplication.OBJECTIVES:We aimed to characterize the infection of rat osteoblasts (OBCs) with JUNV and its consequence on the modulation of osteogenic genes expression, thus studying the ability of this virus to induce cell differentiation. In addition, we evaluated the effect of purinergic agonists on viral replication.METHOD:Quantification of infectivity by plaque forming unit (PFU) assay, synthesis of viral proteins by western blot and immunofluorescence, and expression of osteogenic differentiation markers (ODM) by quantitative real-time polymerase chain reaction were employed.RESULTS:Infection of OBCs with JUNV (MOI 0.01 PFU/cell) showed a peak of infectivity, reaching 1.5 × 105 PFU/mL at the second day post-infection (p.i.). A marked restriction in multiplication was detected at day 7 p.i. that did not impair the establishment of a persistent stage of infection in OBCs. Analysis of mRNAs corresponding to ODM such as alkaline phosphatase, bone sialo-protein, and bone morphogenetic proteins (BMPs) 4 and 6 revealed that only the levels of BMP-6 were significantly higher in infected cells. Treatment with the purinergic agonists ATPγS, UTP, ADP, or UDP diminished viral titer and reduced the expression of the viral nucleoprotein. Also, treatment with 10 μM ATPγS reduced the stimulation of BMP-6 expression induced by the infection.CONCLUSIONS:These data demonstrate that JUNV is capable of infecting OBCs and point out BMP-6 as a key factor during this process.Fil: Ayala Peña, Victoria Belen. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Armiento, María Nieves. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernandez Bell Fano, Pablo Maria. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santillan, Graciela Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Scolaro, Luis Alberto. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica. Laboratorio de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Probabilistic reference model for hourly PV power generation forecasting

This paper presents a new probabilistic forecasting model of the hourly mean power production in a Photovoltaic (PV) plant. It uses the minimal information and it can provide probabilistic forecasts in the form of quantiles for the desired horizon, which ranges from the next hours to any day in the future. The proposed model only needs a time series of hourly mean power production in the PV plant, and it is intended to fill a gap in international literature where hardly any model has been proposed as a reference for comparison or benchmarking purposes with other probabilistic forecasting models. The performance of the proposed forecasting model is tested, in a case study, with the time series of hourly mean power production in a PV plant with 1.9 MW capacity. The results show an improvement with respect to the reference probabilistic PV power forecasting models reported in the literature

Propagação sexual e assexual de Brosimum Alicastrum Swartz em Campeche, México

Brosimum alicastrum is a tree species in Mexico with wide potential for animal and human food, which is distributed naturally with no silvicultural management, so there is little information on the propagation methods of the species. The objective of this work was to analyze the scientific research published on B. alicastrum, through literature review to know the techniques that exist on its propagation. In addition, the quality of the seedling obtained by sexual propagation and asexual methods (cuttings, layers and grafts) was evaluated in the nursery, by means of experimental designs. 550 scientific articles on B. alicastrum were found, the disciplines where they were published were: Ecology (44.18%), Botany (13.27%), Forest Sciences (11.27%, of which 2.54% worked propagation in the nursery), Zoology (11.09%), Agriculture (9.64%), Anthropology (5.45%) and others (5.10%). Regarding the seed propagation method, the best seedling quality was associated with low porosity substrates (bush soil) and containers with large diameters (36 cm). In the case of asexual propagation, with the layering method when peat moss was used as the substrate 90% survival was obtained, and by grafting of lateral plating 75% yield was found. Due to the little research that exists on the propagation of the species, it is recommended that the selection of the propagation technique is based on the purpose of the seedling; if it is required to shorten the seed production cycles of B. alicastrum the asexual techniques grafting and layering can be more efficient.Brosimum alicastrum es una especie arbórea en México con amplio potencial para la alimentación animal y humana, que se distribuye de manera natural con nulo manejo silvícola, por lo que existe poca información sobre los métodos de propagación de la especie. El objetivo de este trabajo fue analizar la producción científica reportada sobre B. alicastrum, mediante minería de textos para conocer las técnicas que existen sobre su propagación. De igual forma, evaluar en vivero la calidad de plántulas obtenidas por métodos de propagación sexual y asexual (estacas, acodos e injertos) mediante diseños experimentales.  Se encontraron 550 artículos científicos sobre B. alicastrum, las disciplinas donde se publicaron fueron: Ecología (44,18%), Botánica (13,27%), Ciencias Forestales (11,27%, de los cuales el 2,54% trabajó propagación en vivero), Zoología (11,09%), Agricultura (9,64%), Antropología (5,45%) y otras (5,10%). Respecto al método de propagación por semilla, la mejor calidad de plántula se asoció con sustratos de baja porosidad (tierra de monte) y a contenedores con diámetros grandes (36 cm). Para el caso de la propagación asexual por acodos, cuando se empleó turba como sustrato se obtuvo 90% de sobrevivencia, y por injerto de enchape lateral se encontró 75% de prendimiento. En virtud de la poca investigación que existe sobre la propagación de la especie se recomienda que la selección de la técnica de propagación esté en función de la finalidad de la plántula. Las técnicas asexuales de injerto y acodo pueden ser más eficientes en caso de requerir acortar los ciclos de producción de la semilla de B. alicastrum.Brosimum alicastrum é uma espécie arbórea no México com amplo potencial para alimentação animal e humana, que se distribui naturalmente sem manejo silvicultural, portanto, há poucas informações sobre os métodos de propagação da espécie. O objetivo deste trabalho foi analisar a produção científica reportada sobre B. alicastrum por meio da mineração de textos para conhecer as técnicas existentes sobre a sua propagação e avaliar em viveiro a qualidade das mudas obtidas por métodos de propagação sexual e assexuada (estaquia, estratificação e enxertia) por meio de delineamentos experimentais. Foram encontrados 550 artigos científicos sobre B. alicastrum, as áreas onde foram publicados foram: Ecologia (44,18%), Botânica (13,27%), Ciências Florestais (11,27%, dos quais 2,54% trabalhavam com propagação em viveiros), Zoologia (11,09%) , Agricultura (9,64%), Antropologia (5,45%) e outros (5,10%). Em relação ao método de propagação por semente, a melhor qualidade das mudas foi associada a substratos de baixa porosidade (solo de montanha) e a recipientes com grandes diâmetros (36 cm). No caso de propagação assexuada por estratificação, quando se utilizou turfa como substrato, obteve-se 90% de sobrevivência e, por enxertia de faceta lateral, encontrou-se 75% de descolamento. Devido às poucas pesquisas que existem sobre a propagação da espécie, recomenda-se que a seleção da técnica de propagação seja baseada na finalidade das plantas. As técnicas assexuadas de enxerto e estratificação podem ser mais eficientes se for necessário encurtar os ciclos de produção de sementes de B. alicastrum

Análisis bibliométrico de la investigación científica sobre modelos para estimar evapotranspiración en cultivos agrícolas

The objective was to analyze the spatio-temporal evolution of the production of scientific articles that used some methodology for the estimation of potential evapotranspiration in an agricultural crop (ETP). We compiled 475 texts available on the Web of Science. The models to estimate the most frequent ETP were those proposed by FAO-Penman-Monteith (31.79%), Pemnan-Monteith (26.11%), and Thornthwaite (11.37%), and were applied mainly to maize, sorghum, soybean and potato crops, in countries such as the United States, China, Brazil, and India, agricultural leaders worldwide. It was found that there was an exponential growth in the publication of texts from 1984 to 2020 (R2 = 0.7624), which demonstrates the relevance of the topic as a mechanism to make water use more efficient.El objetivo fue analizar la evolución espacio-temporal de la producción de artículos científicos que utilizaron alguna metodología para la estimación de la evapotranspiración potencial en un cultivo agrícola (ETP). Se recopilaron 475 artículos científicos disponibles en la Web of Science. Los modelos para estimar la ETP de mayor frecuencia fueron los propuestos por FAO-Penman-Monteith (31.79%), Pemnan-Monteith (26.11%), y Thornthwaite (11.37%), y se aplicaron principalmente a cultivos de maíz, sorgo, soya y papa, en países como Estados Unidos, China, Brasil, e India, lideres agrícolas a nivel mundial. Se encontró que ocurrió un crecimiento exponencial en la publicación de los textos de 1984 a 2020 (R2 = 0.7624), lo que denota la relevancia del tema como un mecanismo para eficientizar el agua

Electric power distribution planning tool based on geographic information systems and evolutionary algorithms

The expansion of electric distribution networks in new geographic areas is a tedious task. Once the position of the low voltage power substations has been decided, the planning engineers need to select the routes for the new power lines ensuring more efficient connections among the substations. This paper presents the methodology followed to plan the set of overhead power lines which achieves the optimal distribution network with the minimum installation and maintenance costs. The methodology is based on the use of Geographic Information Systems, which provide the needed functions to find feasible and economic routes for the new overhead power lines linking the substations, and an evolutionary algorithm which selects the optimal links. The application of the proposed methodology allows finding the optimal solution under an economic perspective in an automatic manner

Day-ahead probabilistic photovoltaic power forecasting models based on quantile regression neural networks

This paper presents the results obtained in the development of probabilistic short-term forecasting models of the power production in a photovoltaic power plant for the day-ahead. The probabilistic models are based on quantile regression neural networks. The structure of such neural networks is optimized with a genetic algorithm which selects the values for the main parameters of the neural network and the variables used as inputs. These input variables are selected among a set of variables which includes chronological, astronomical and forecasted weather variables related to the location of the power plant. The forecasts correspond to quantiles of the hourly power generation in the photovoltaic power plant for the daytime hours of the day-ahead. The forecasts are obtained in the first hours of the day, allowing their use for preparing bid offers for the day-ahead in electricity markets

Short-term net load forecast in distribution networks with PV penetration behind the meter

In recent years there has been a strong expansion of photovoltaic (PV) distributed generation systems. A high PV penetration level can cause uncertainty in the operation and management processes carried out by electric utilities, since most meters register the net load, i.e., the actual load minus the power generated by the PV systems behind the meter. The goal of this paper was to analyze the difference in the net load forecasting error achieved by models using or not using behind-the-meter PV generation data. The PV plant is connected to the lower voltage side of the power substation, representing a penetration level of more than 35% of the total load. The study shows that the best forecasting results are obtained with an indirect approach using two forecasting models, one for the total load and the other for the PV generation. However, the difference with respect to the results obtained with a unique net load forecasting model is almost negligible, which may be of special interest for power system distributors or other agents who do not have access to behind-the-meter generation data

Epidemiology of intra-abdominal infection and sepsis in critically ill patients: "AbSeS", a multinational observational cohort study and ESICM Trials Group Project

PURPOSE: To describe the epidemiology of intra-abdominal infection in an international cohort of ICU patients according to a new system that classifies cases according to setting of infection acquisition (community-acquired, early onset hospital-acquired, and late-onset hospital-acquired), anatomical disruption (absent or present with localized or diffuse peritonitis), and severity of disease expression (infection, sepsis, and septic shock). METHODS: We performed a multicenter (n = 309), observational, epidemiological study including adult ICU patients diagnosed with intra-abdominal infection. Risk factors for mortality were assessed by logistic regression analysis. RESULTS: The cohort included 2621 patients. Setting of infection acquisition was community-acquired in 31.6%, early onset hospital-acquired in 25%, and late-onset hospital-acquired in 43.4% of patients. Overall prevalence of antimicrobial resistance was 26.3% and difficult-to-treat resistant Gram-negative bacteria 4.3%, with great variation according to geographic region. No difference in prevalence of antimicrobial resistance was observed according to setting of infection acquisition. Overall mortality was 29.1%. Independent risk factors for mortality included late-onset hospital-acquired infection, diffuse peritonitis, sepsis, septic shock, older age, malnutrition, liver failure, congestive heart failure, antimicrobial resistance (either methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, extended-spectrum beta-lactamase-producing Gram-negative bacteria, or carbapenem-resistant Gram-negative bacteria) and source control failure evidenced by either the need for surgical revision or persistent inflammation. CONCLUSION: This multinational, heterogeneous cohort of ICU patients with intra-abdominal infection revealed that setting of infection acquisition, anatomical disruption, and severity of disease expression are disease-specific phenotypic characteristics associated with outcome, irrespective of the type of infection. Antimicrobial resistance is equally common in community-acquired as in hospital-acquired infection.status: publishe