The objective of this study was to evaluate the utility of the BlightPro decision support system (DSS) for late blight management using computer simulation and field tests. Three fungicide schedules were evaluated: (i) calendar-based (weekly) applications, (ii) applications according to the DSS, or (iii) no fungicide. Simulation experiments utilized 14 years of weather data from 59 locations in potato-producing states. In situations with unfavorable weather for late blight, the DSS recommended fewer fungicide applications with no loss of disease suppression; and, in situations of very favorable weather for late blight, the DSS recommended more fungicide applications but with improved disease suppression. Field evaluation was conducted in 2010, 2011, 2012, and 2013. All experiments involved at least two cultivars with different levels of resistance. DSS-guided and weekly scheduled fungicide treatments were successful at protecting against late blight in all field experiments. As expected, DSS-guided schedules were influenced by prevailing weather (observed and forecast) and host resistance and resulted in schedules that maintained or improved disease suppression and average fungicide use efficiency relative to calendar-based applications. The DSS provides an interactive system that helps users maximize the efficiency of their crop protection strategy by enabling well-informed decisions.

Precision agriculture has emerged as a revolutionary technology, which transforms farming related data into useful information for agricultural decision-making. Th is paper compares precision farming technology with calendar-based approach in scheduling fungicide applications to manage potato (Solanum tuberosum L.) late blight disease. Th ree fungicide scheduling strategies were evaluated: calendar-based strategy, BlightPro decision support system based strategy (DSS-based strategy), and unsprayed control. Using results from 14 yr of computer simulation experiments for 59 locations in the United States, we constructed distributions of net return to all costs excluding fungicide cost and application cost per 0.41 ha (net return per 0.41 ha) for the calendar-based and DSS-based strategies at each location. Th ese distributions were then compared using three risk management methods: stochastic dominance, stochastic dominance with respect to a function, and stochastic effi ciency with respect to a function. Th e DSS-based strategy was identifi ed as the most eff ective approach to manage late blight in terms of disease suppression, net return per 0.41 ha, and risk-adjusted net return. Results indicate that the DSS-based strategy is the preferred method to schedule fungicide applications. Under high disease pressure circumstances, the economic benefi ts to potato growers of adopting the precision agriculture technology ranged from US$30 to $573 per 0.41 ha. For risk neutral individuals, who are concerned about the diff erence between average net return per 0.41 ha, the benefi ts ranged from $30 to $305 per 0.41 ha. Except for growers raising the moderately resistant potato cultivars, more risk averse individuals tended to benefi t more from adopting the precision agriculture technology, with benefi ts ranging from $38 to $573 per 0.41 ha. Abbreviations: AUDPC, area under disease progress curve; CE, certainty equivalent; DSS, decision support system; FSD, fi rst-degree stochastic dominance; RP, risk premium; net return per 0.41 ha, net return to all costs excluding fungicide cost and application cost per 0.41 ha; SERF, stochastic effi ciency with respect to a function; SSD, second-degree stochastic dominance; SDRF, stochastic dominance with respect to a function. Core ideas• Th e benefi ts of adopting precision farming technology was investivated in scheduling fungicide applications to manage potato late blight.• Th e precision farming technology is the preferred method to schedule fungicide applications in terms of disease suppression, net return per 0.41 ha, and risk-adjusted net return.• Th e increased adoption of the precision farming technology would help manage late blight, limit potential crop losses, and improve net returns.

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Osteoarthritis (OA) is the most frequently diagnosed joint disorder worldwide with increasing prevalence and crucial impact on the quality of life of affected patients through chronic pain, decreasing mobility and invalidity. Although some risk factors, such as age, obesity and previous joint injury are well established, the exact pathogenesis of OA on a cellular and molecular level remains less understood. Today, the role of nitrosative and oxidative stress has not been investigated conclusively in the pathogenesis of OA yet. Therefore, the objective of this study was to identify biological substances for oxidative and nitrosative stress, which mirror the degenerative processes in an osteoarthritic joint. 69 patients suffering from a diagnosed knee pain participated in this study. Based on the orthopedic diagnosis, patients were classified into an osteoarthritis group (OAG, n=24) or in one of two control groups (meniscopathy, CG1, n=11; anterior cruciate ligament rupture, CG2, n=34). Independently from the study protocol, all patients underwent an invasive surgical intervention which was used to collect samples from the synovial membrane, synovial fluid and human serum. Synovial biopsies were analyzed histopathologically for synovitis (Krenn-Score) and immunohistochemically for detection of end products of oxidative (8-isoprostane F2α) and nitrosative (3-nitrotyrosine) stress. Additionally, the fluid samples were analyzed for 8-isoprostane F2α and 3-nitrotyrosine by competitive ELISA method. The analyzation of inflammation in synovial biopsies revealed a slight synovitis in all three investigated groups. Detectable concentrations of 3-nitrotyrosine were reported in all three investigated groups without showing any significant differences between the synovial biopsies, fluid or human serum. In contrast, significant increased concentrations of 8-isoprostane F2α were detected in OAG compared to both control groups. Furthermore, our data showed a significant correlation between the histopathological synovitis and oxidative stress in OAG (r=0.728, P<0.01). There were no significant differences between the concentrations of 8-isoprostane F2α in synovial fluid and human serum. The findings of the current study support the hypothesis that oxidative and nitrosative stress are components of the multi-factory pathophysiological formation of OA. It seems reasonable that an inflammatory process in the synovial membrane triggers the generation of oxidative and nitrosative acting substances which can lead to a further degradation of the articular cartilage. Based on correlations between the observed degree of inflammation and investigated biomarkers, especially 8-isoprostane F2α seems to be a novel candidate biomarker for OA. However, due to the finding that also both control groups showed increased concentrations of selected biomarkers, future studies have to validate the diagnostic potential of these biomarkers in OA and in related conditions of the knee joint.