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In addition to the weather conditions, agronomic practices can have a major influence on maize crop yield and contamination with mycotoxins. In this work, the effect of different irrigation systems (flood vs. sprinkler irrigation), sprinkler irrigation management (low vs. high frequency, daytime vs. nighttime irrigation) and tillage practices (conventional tillage, no tillage with or without crop stover) on crop yield and the contamination with aflatoxins (AFs), fumonisins (FUM) and deoxynivalenol (DON) were evaluated in the maize grain from two experimental maize fields. No aflatoxins were detected in any of the samples analyzed. DON and FUM levels were significantly higher when the sprinkler irrigation was performed at nighttime (0.54 and 1.21 mg kg−1, respectively) as compared to daytime (0.38 and 0.45 mg kg−1). Likewise, DON and FUM were greater when irrigation frequency was low (0.61 and 1.09 mg kg−1, respectively) in comparison with high frequency (0.30 and 0.57 mg kg−1). DON concentrations were significantly higher in fields with sprinkler irrigation (0.53 mg kg−1) as compared to flood irrigation (0.19 mg kg−1), while the levels of FUM were very similar regardless of the maize irrigation system. Mycotoxin concentrations were not affected by the different soil tillage practices. This highlights the importance of implementing crop management practices to minimize the risk of mycotoxin contamination in maize. [ABSTRACT FROM AUTHOR]

Copyright of Revista Internacional de Pensamiento Político is the property of Revista Internacional de Pensamiento Politico - Universidad Pablo de Olavide and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Facultad de Ingeniería Universidad de Antioquia is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La capacidad de los laboratorios para detectar el SARS-CoV-2 ha sido clave para la contención de la enfermedad por coronavirus 2019 (COVID-19). El 15 de marzo de 2020, se declaró en el Perú el estado de emergencia nacional, contando el Instituto Nacional de Salud (INS) con la capacidad para realizar el diagnóstico molecular de 41 pruebas diarias. En 10 meses, el INS incrementó su capacidad a 6,000 pruebas diarias, procesando 575,493 muestras equivalentes al 36.2% de las pruebas a nivel nacional durante la primera ola pandémica. [ABSTRACT FROM AUTHOR]

Clasificar a los microorganismos en grupos de riesgo biológico en seguridad y custodia permite desarrollar medidas de protección en aquellos de riesgo alto y, moderado, asi como crear códigos de conducta en el personal para su uso legal y fines autorizados. Por ello, se elaboró un inventario para clasificar a los microorganismos del Centro Nacional de Salud Pública (CNSP) del Instituto Nacional de Salud (INS) en grupos de riesgo biológico. Se identificaron 121 microorganismos; según el criterio de bioseguridad, el 84% se clasifican en el grupo de riesgo 2 (102) y el 16% en el riesgo 3 (19). En biocustodia, se registraron 53 microorganismos en el grupo de riesgo bajo (44%), 56 en riesgo moderado (46%) y 12 en riesgo alto (10%); siendo necesario adoptar y mantener medidas especiales de protección. [ABSTRACT FROM AUTHOR]

Copyright of Anales de la Cátedra Francisco Suárez is the property of Anales de la Catedra Francisco Suarez and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Human mobility is one of the most important concerns in smart city initiatives and is especially relevant when combined with accessibility issues. This paper describes work in the context of the Access@City Research Project, which seeks to improve the accessibility in the public transport system by using available information (open data, semantic-aware knowledge) provided by transport organisations. However, these organisations provide partial data, and a lot of information is still available only on their websites, or simply does not exist. This absence can be tackled using a playful approach – the use of gaming apps to obtain and update accessibility information. In this paper, we describe the use of a hybrid reality game (HRG) to enrich information regarding the accessibility of subway stations. In turn, the player improves her score, which is included as part of the game. The correlation between these observations is able to provide, in a relatively short time, an accurate description of the accessibility of these stations. In summary, this playful approach makes it possible to recover a set of accessibility data that ultimately provide these smart capabilities, which are the core of this 'accessible city' endeavour. [ABSTRACT FROM AUTHOR]

Irrigation and soil management can impact soil nitrous oxide (N2O) emissions. Flood and sprinkler irrigation systems together with conventional tillage are the main practices used in the high yielding maize systems in Mediterranean Spain. The objective of this field work was to quantify the effect of the irrigation system (i.e., flood, F; and sprinkler, S) and the soil tillage system (i.e., conventional tillage, CT; no‐tillage maintaining the maize stover, NTr; and no‐tillage removing the maize stover, NT) on the N2O emissions from the soil during 3 yr (2015, 2016, and 2017). S irrigation, with mean values of 1.35 kg N2O‐N ha−1 yr−1 throughout the 3 yr, obtained 42% lower N2O emissions than F irrigation. On average of the three growing seasons, yield‐scaled N2O emissions by grain yield and by grain N uptake in F irrigation were two‐fold higher than in S irrigation. Moreover, in one out of three growing seasons (2017), no‐tillage systems (i.e., NTr and NT) showed greater yield‐scaled N2O emissions compared with CT. The higher maize grain yield with the S irrigation compared to F irrigation, as well as the lower N2O emissions reported under S irrigation resulted in the reduction of the yield‐scaled N2O emissions. Our findings highlight the role of sprinkler irrigation decreasing N2O emissions in comparison to flood irrigation in Mediterranean agroecosystems. [ABSTRACT FROM AUTHOR]

Sprinkler irrigation with solid-set systems easily allows changing irrigation frequency. We studied, under field conditions and during 3 yr, the effects of irrigation frequency (two events per week or daily) and daytime vs. nighttime irrigation on microclimatic changes, soil matric potential, growth, yield, and water use of maize (Zea mays L.). Microclimatic changes (decrease of air temperature and vapor pressure deficit, and of canopy temperature) were slightly larger and lasted for more time after the irrigation event with low frequency irrigation. Increasing irrigation frequency during daytime resulted in a lower soil matric potential. Irrigating at nighttime resulted in higher maize height (+3%) and yield (+10%) than irrigating at daytime. The high irrigation frequency decreased maize height (-7%) and yield (-5%) compared with the low irrigation frequency when irrigation was performed at daytime but not at nighttime. The Na+ content of the plant was doubled with daytime sprinkler irrigation compared with nighttime irrigation, and was increased by 30% when the irrigation frequency was increased. Water use efficiency (WUE) was not affected by irrigation frequency when irrigating at nighttime, but it decreased with the increase of irrigation frequency when irrigation was applied during daytime. Sprinkler irrigation with solid-set must be applied at night to obtain the maximum maize yield and WUE. Irrigation frequency is not relevant for sprinkler irrigation of maize applied at night, but high irrigation frequency should be avoided when maize is sprinkler irrigated during daytime to avoid yield and WUE decreases. [ABSTRACT FROM AUTHOR]

Despite alfalfa's global importance, there is a dearth of crop simulation models available for predicting alfalfa growth and yield with its associated composition. The objectives of this research were to adapt the CSM-CROPGRO Perennial Forage Model for simulating alfalfa growth and yield and to describe model adaptation for this species. Data from six experimental plots grown under sprinkler irrigation in the Ebro valley (Northeast Spain) were used for model adaptation. Starting with parameters for Bracharia brizantha, the model adaptation was based on values and relationships reported from the literature for cardinal temperatures and dry matter partitioning. A Bayesian optimizer was used to optimize temperature effects on photosynthesis and daylength effects on partitioning and an inverse modeling technique was employed for nitrogen fixation rate and nodule growth. The calibration of alfalfa tissue composition was initiated from soybean composition analogy but was improved with values from alfalfa literature. There was considerable iteration in optimizing parameters for the processes outlined above where comparisons were made to measured data. After adaptation, the Root Mean Square Error and d-statistic of harvested herbage averaged across 58 harvests (yield range: 990-4617 kg ha-1) were 760 kg ha-1 and 0.75, respectively. In addition, good agreement was observed for Leaf Area Index (LAI) (LAI range: 0.1-6.7) with d-statistic of 0.71. Simulated belowground mass was within the range of literature values. The results of this study showed that CROPGRO-PFM-Alfalfa can be used to simulate alfalfa growth and development. Further testing with more extensive datasets is needed to improve model robustness. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Cuerpo Médico del Hospital Nacional Almanzor Aguinaga Asenjo is the property of Cuerpo Medico del Hospital Nacional Almanzor Aguinaga Asenjo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During sprinkler irrigation some water is lost due to drift and evaporation. After irrigation, plant-intercepted water is lost due to evaporation. The water loss causes microclimatic changes, which may involve positive or negative plant physiological responses. We studied the changes in net photosynthesis of maize (Zea mays L.) and alfalfa (Medicago sativa L.) associated with irrigation with a solid-set sprinkler system. For each species, measurements were made simultaneously in two plots, one being irrigated and the other not being irrigated. Two automatic canopy chambers connected to two CO2 infrared gas analyzers were used. Sprinkler irrigation decreased air temperature (1.5°C on maize, 1.7°C on alfalfa), air vapor pressure deficit (VPD) (0.44 kPa for both crops) and canopy temperature (5.1°C on maize, 5.9°C on alfalfa). Sprinkler irrigation decreased maize net photosynthesis on 80% of the days and the mean reduction was 19%. Sprinkler irrigation increased alfalfa net photosynthesis on 36% of days, decreased it on 14% of days, and had no effect on half of the days. The decrease of maize net photosynthesis during sprinkler irrigation was linked to the high leaf wettability (water contact angles from 60-80°) and the decrease in temperature below the optimum range for photosynthesis. The higher hydrophobicity of alfalfa leaves (water contact angles >120°) and the wide range of optimum temperature for alfalfa photosynthesis may be the reasons why photosynthesis remained unaffected by sprinkler irrigation. The results suggest that daytime sprinkler irrigation with solid-set should be avoided for maize but can be used for alfalfa. [ABSTRACT FROM AUTHOR]

The magnitude and duration of corn transpiration reduction during center-pivot sprinkler irrigation was analyzed on a commercial plot. The irrigation event was defined as the period during which the pivot arm was passing over the transect AC and water droplets were moistening the plants (moist treatment). Corn transpiration rates were measured at three spots of that transect and simultaneously at another spot (dry treatment) located approximately 270 m east from the transect AC. Corn transpiration rates for the moist treatment location were reduced by 30-36% compared to the dry treatment location during the irrigation event. After irrigation, the transpiration reduction lasted for 1.8-2.6 h, and ranged from 22-29%. The gross wind drift and evaporation losses ranged from 10-13% of the applied water, whereas the net interception losses were 2% of the applied water. Considering the observed corn transpiration reduction during and after the irrigation, the net sprinkler evaporation losses ranged from 11-13% of the applied water, with no relevant differences along the pivot arm. [ABSTRACT FROM AUTHOR]

Abstract: The microclimatic (air temperature and vapor pressure deficit (VPD)) and physiological (canopy temperature and plant transpiration) changes due to center pivot sprinkler irrigation were monitored at a commercial plot of maize (Zea mays L.). Two treatments were considered: (a) moist, measurements taken at three spots on a transect when the pivot was running over it; (b) dry, measurements taken simultaneously at a fourth spot D, 270m apart. A total of 34 irrigation events were monitored, seven of which included plant transpiration measurements. For the transpiration-measured irrigation events, significant (P =0.05) reductions in the monitored variables for the moist treatment were observed for 0.6–2.1h before, during and 0.5–2.4h after the irrigation. The average decreases for the phase during were 1.8–2.1°C for air temperature, 0.53–0.61kPa for VPD, 3.1–3.8°C for canopy temperature, and 0.22–0.28mmh−1 (30–36%) for transpiration. Lower reductions were found for the phases before and after. The duration of the microclimatic changes decreased as the distance from the center of the pivot increased (from 3.9 to 2.2h), but the duration of the physiological changes was similar in the different pivot arm portions (≈4h). Microclimatic and physiological changes were higher in drier and warmer days. Transpiration reduction due to irrigation was higher as closer to the center of the pivot and represented 5–7% of the applied water. The estimated reduction of ET represented 1.5–1.8% of the applied water. The reduction of transpiration and ET is positive because it represents a reduction in irrigation requirements. The decrease in maize canopy temperature could be positive or negative depending on its effect on photosynthesis. [Copyright &y& Elsevier]

Nitrogen fertilization of corn (Zea mays L.) following alfalfa (Medicago sativa L.) can be reduced due to the considerable amounts of N released by this legume, but most research on this subject has been conducted in rainfed areas. The objective of this study was to determine the response of corn to N fertilization following high-yielding alfalfa in irrigated semiarid conditions. Seven field experiments were conducted between 2006 and 2008 in the Ebro Valley, Northeast Spain. Fields were sprinkler, furrow, or flood irrigated. Treatments comprised six N rates (0, 50, 100, 150,200, and 300 kg N ha-1) applied to corn as two sidedressings. The N contained in the alfalfa roots and crowns ranged from 54 to 212 kg N ha-1, depending on the field. Alfalfa provided enough N to the subsequent corn to achieve from 10.3 to 16.7 Mg ha-1 of grain yield without N fertilization. Nitrogen fertilization was nor required to maximize corn yields in three of seven fields. In the other four sites, the optimum nitrogen rates (ONR) that maximized corn yields ranged from 115 to 196 kg N ha-1. The highest ONR generally were observed in flood-irrigated fields than in sprinkler-irrigated fields. Net economic return from N fertilization was maximized at N rates between 0 and 150 kg N ha-1, suggesting that N applications for corn succeeding alfalfa can be greatly reduced compared to rates normally applied in irrigated semiarid areas (300 kg N ha-1). [ABSTRACT FROM AUTHOR]

• Soil GHG emissions were measured during two years in irrigated maize. • Irrigation frequency had a minor impact on GHG emissions. • Nighttime irrigation increased soil N 2 O emissions. • Nighttime irrigation enhanced maize grain yield by 13%. • N 2 O scaled emissions was not affected by the irrigation management. Irrigation management may influence soil greenhouse gas emissions (GHG). Solid-set sprinkler irrigation systems allow to modify the irrigation time and frequency. The objective of this study was to quantify the effect of two irrigation times (daytime, D; nighttime, N) and two irrigation frequencies (low, L; high, H) on soil carbon dioxide (CO 2), methane (CH 4), and nitrous oxide (N 2 O) emissions in a solid-set sprinkler-irrigated maize (Zea mays L.) field located in NE Spain during 2015 and 2016 growing seasons and the fallow period between growing seasons. Compared with D irrigation, N irrigation increased soil water content (0–5 cm) in both growing seasons. Irrigation management did not affect CH 4 emissions and the soil acted as a sink of CH 4. Cumulative CO 2 emissions were affected by the measurement period (growing season vs fallow) with the greatest values in 2015 growing season, being 81 and 32% higher over the fallow period and over the 2016 growing season, respectively, due to the effect of the preceding crop, alfalfa, and a better soil moisture conditions for the microorganism activity. Similarly, cumulative N 2 O emissions showed the highest values in 2015, reporting values 90 and 51% greater than the fallow period and the 2016 growing season, respectively. Moreover, N irrigation increased cumulative N 2 O emissions by 29% compared with D irrigation, but irrigation frequency did not affect cumulative N 2 O emissions. Irrigation time did not affect cumulative N 2 O emissions scaled per grain yield or per N uptake because N irrigation increased maize yield by 11% compared with D irrigation. Due to the lack of differences in the scaled N 2 O emissions, N irrigation should be consider as an appropriate strategy to optimize grain yield without compromising soil GHG emissions per unit of grain yield in Mediterranean agroecosystems. [ABSTRACT FROM AUTHOR]

In this study we evaluated the leaf surface properties of maize populations native to different water availability environments. Leaf surface topography, wettability and gas exchange performance of five maize populations from the Sahara desert, dry (south) and humid (north-western) areas of Spain were analysed. Differences in wettability, stomatal and trichome densities, surface free energy and solubility parameter values were recorded between populations and leaf sides. Leaves from the humid Spanish population with special regard to the abaxial side, were less wettable and less susceptible to polar interactions. The higher wettability and hydrophilicity of Sahara populations with emphasis on the abaxial leaf surfaces, may favour dew deposition and foliar water absorption, hence improving water use efficiency under extremely dry conditions. Compared to the other Saharan populations, the dwarf one had a higher photosynthesis rate suggesting that dwarfism may be a strategy for improving plant tolerance to arid conditions. The results obtained for different maize populations suggest that leaf surfaces may vary in response to drought, but further studies will be required to examine the potential relationship between leaf surface properties and plant stress tolerance. [ABSTRACT FROM AUTHOR]

Abstract: The effects of years of extreme rainfall events on maize water-use under traditional flooding irrigation in a Mediterranean landplane were estimated through a simulation assessment; combining a weather generator with an agrohydrological simulation model. Two options: “Fully Irrigation” and “Deficit Irrigation” were considered in the simulations as the extreme water-management situations. Besides, a 2m depth shallow water table and Free Drainage were considered as the typical extreme situations that can be found at the bottom of the simulated soil layer. Thirty “Dry” (DY) and “Wet” (WY) years were randomly selected from the weather generator output. The model SWAP was used to simulate the relative transpiration (RT), i.e. ratio between actual and maximum maize transpiration, actual maize evapotranspiration (ETC), percolated water and capillary rising during wet and dry years and for each of the irrigation and bottom condition options. According to the modelling results, average mean RT is about 80% and 90% in dry and wet years, respectively. RT and ETC variability are very high under dry conditions although such variability is notably reduced if a suitable irrigation option is considered. Capillary rising can play a very important role during dry years in those places where irrigation is not enough, but water table is relatively shallower. On the other hand, a shallower water table can carry out RT reductions during wet years, due to water excess, although these negative effects are comparatively lower than those produced by rain scarcity. Besides, percolated water during wet years is very high, particularly in well-irrigated farms. [Copyright &y& Elsevier]

A comparison between experimental and simulated data, considering the Priestley–Taylor (PT) and Penman–Monteith (PM) reference-evapotranspiration (ET0) approaches was carried out. Experimental data, obtained from an irrigation assessment, conducted during the 1995 and 1996 maize growth-seasons at Zaragoza, Spain, was compared to the mechanistic-model SWAP simulation-results, considering each of the ET0 calculation approaches in the model input. Soil hydraulic properties, meteorological data, seeding and harvest dates, crop water management and other experimental data were used as SWAP input. As corresponding to the windy and dry conditions found in many Mediterranean landplanes, PT-ET0 values were significantly lower than PM-ET0 calculations. Furthermore, simulated actual evapotranspirations considering the PT approach (PT-ETc) were lower than those found in the simulations that consider the PM approach (PM-ETc). Correspondingly, simulated drainage flux and soil water contents were higher when the PT-ET0 approach was used. The correlation coefficients between simulated and measured actual maize evapotranspirations and soil water contents were statistically significant, but the same for both ET0 calculation approaches. Mean and median differences between actual and simulated maize water-use were not statistically different from zero for both considered ET0 calculation approaches. Experimental data variability was significantly higher than simulated variability. The comparisons among the evaluated irrigation options, made with the experimental water-use data, lead almost to the same conclusions than those achieved from the simulated maize water-use. Considering PM-ETc rather than PT-ETc yields no statistical difference in the modeling-based conclusions. According to the obtained results, the PT approach could be used under Mediterranean conditions for comparative assessments aimed to support irrigation decision-making. [Copyright &y& Elsevier]