323 research outputs found

    Web-based phosphine fumigation monitoring with active sensor validation confirms lethality in stored grains: Presentation

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    The predominant measurement technologies for fumigation gases over the past 60 years include colorimetric tubes, photoionization detectors, and electrochemical sensors. Their limitations and inaccuracies are well documented. Spectros Instruments has shown non-dispersive infrared monitoring (NDIR) to be a superior analytical tool for the practical measurement of fumigation gases as shown in Table 1. Any compliant fumigation monitor must be accurate, reliable and affordable. Stored Product Protection has additional requirements in remote regions such as Central China and Western Australia. In these cases, the value of real time access via the internet to fumigation data collected with NDIR Technology from a remote location adds heretofore unknown benefits. Allocation of manpower and materials resources are optimized by access to information about fumigant gas levels in grain storages via the internet. Data is automatically transferred to a central database that can be accessed in real-time from any location with internet access. Intelligent monitors with built-in diagnostics tracking barometric pressure, temperature, sample flows and detector voltages are described. This data collection, data warehousing and reporting platform maintains measurement traceability to certified compliance with secure, encrypted electronic notebook format. Knowing REAL phosphine concentrations allows informed decisions to be made to achieve required CxT and avoid situations leading to target pest phosphine resistance.The predominant measurement technologies for fumigation gases over the past 60 years include colorimetric tubes, photoionization detectors, and electrochemical sensors. Their limitations and inaccuracies are well documented. Spectros Instruments has shown non-dispersive infrared monitoring (NDIR) to be a superior analytical tool for the practical measurement of fumigation gases as shown in Table 1. Any compliant fumigation monitor must be accurate, reliable and affordable. Stored Product Protection has additional requirements in remote regions such as Central China and Western Australia. In these cases, the value of real time access via the internet to fumigation data collected with NDIR Technology from a remote location adds heretofore unknown benefits. Allocation of manpower and materials resources are optimized by access to information about fumigant gas levels in grain storages via the internet. Data is automatically transferred to a central database that can be accessed in real-time from any location with internet access. Intelligent monitors with built-in diagnostics tracking barometric pressure, temperature, sample flows and detector voltages are described. This data collection, data warehousing and reporting platform maintains measurement traceability to certified compliance with secure, encrypted electronic notebook format. Knowing REAL phosphine concentrations allows informed decisions to be made to achieve required CxT and avoid situations leading to target pest phosphine resistance

    Inside Out: Detecting Learners' Confusion to Improve Interactive Digital Learning Environments

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    Confusion is an emotion that is likely to occur while learning complex information. This emotion can be beneficial to learners in that it can foster engagement, leading to deeper understanding. However, if learners fail to resolve confusion, its effect can be detrimental to learning. Such detrimental learning experiences are particularly concerning within digital learning environments (DLEs), where a teacher is not physically present to monitor learner engagement and adapt the learning experience accordingly. However, with better information about a learner's emotion and behavior, it is possible to improve the design of interactive DLEs (IDLEs) not only in promoting productive confusion but also in preventing overwhelming confusion. This article reviews different methodological approaches for detecting confusion, such as self-report and behavioral and physiological measures, and discusses their implications within the theoretical framework of a zone of optimal confusion. The specificities of several methodologies and their potential application in IDLEs are discussed

    The subjective experience of habit captured by self-report indexes may lead to inaccuracies in the measurement of habitual action

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    Commentary on Gardner, B. (2014). A review and analysis of the use of ‘habit’ inunderstanding, predicting and influencing health-related behaviour

    Verbal instructions targeting valence alter negative conditional stimulus evaluations (but do not affect reinstatement rates)

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    Negative conditional stimulus (CS) valence acquired during fear conditioning may enhance fear relapse and is difficult to remove as it extinguishes slowly and does not respond to the instruction that unconditional stimulus (US) presentations will cease. We examined whether instructions targeting CS valence would be more effective. In Experiment 1, an image of one person (CS+) was paired with an aversive US, while another (CS-) was presented alone. After acquisition, participants were given positive information about the CS+ poser and negative information about the CS- poser. Instructions reversed the pattern of differential CS valence present during acquisition and eliminated differential electrodermal responding. In Experiment 2, we compared positive and negative CS revaluation by providing positive/negative information about the CS+ and neutral information about CS-. After positive revaluation, differential valence was removed and differential electrodermal responding remained intact. After negative revaluation, differential valence was strengthened and differential electrodermal responding was eliminated. Unexpectedly, the instructions did not affect the reinstatement of differential electrodermal responding

    Triggering Mechanisms for Motor Actions: The Effects of Expectation on Reaction Times to Intense Acoustic Stimuli

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    Motor actions can be released much sooner than normal when the go-signal is of very high intensity (>100 dBa). Although statistical evidence from individual studies has been mixed, it has been assumed that sternocleidomastoid (SCM) muscle activity could be used to distinguish between two neural circuits involved in movement triggering. We summarized meta-analytically the available evidence for this hypothesis, comparing the difference in premotor reaction time (RT) of actions where SCM activity was elicited (SCM+ trials) by loud acoustic stimuli against trials in which it was absent (SCM- trials). We found ten studies, all reporting comparisons between SCM+ and SCM- trials. Our mini meta-analysis showed that premotor RTs are faster in SCM+ than in SCM- trials, but the effect can be confounded by the variability of the foreperiods employed. We present experimental data showing that foreperiod predictability can induce differences in RT that would be of similar size to those attributed to the activation of different neurophysiological pathways to trigger prepared actions. We discuss plausible physiological mechanisms that would explain differences in premotor RTs between SCM+ and SCM- trials

    STEREO PHOTO SERIES FOR QUANTIFYING BIOMASS FOR THE CERRADO VEGETATION IN CENTRAL BRAZIL

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    As séries de estereo-fotografias para o Cerrado representam uma variação de formas fisionômicas do Cerrado, incluindo campo limpo, campo sujo, cerrado ralo, cerrado sensu stricto e cerrado denso. As áreas incluem fotografias grande angular e um par de estereo-fotografias complementadas com informações sobre o combustível vivo e morto, a estrutura e composição da vegetação. Estas séries de estereo-fotografias são uma importante ferramenta de manejo, que pode ser usada na avaliação de paisagens através da estimativa do combustível vivo e morto, bem como da estrutura da vegetação. Dados de inventário como os fornecidos nestas séries podem ser usados como variáveis para, por exemplo, a avaliação de habitats de animais e insetos, ciclagem de nutrients, microclima e estimativas de seqüestro de carbono . Aqueles que trabalham com pesquisas em fogo encontrarão dados importantes para a predição de consumo de combustível, produção de fumaça e efeitos do fogo durante incêndios florestais e queimadas prescritas

    Heterogeneous ice nucleation properties of natural desert dust particles coated with a surrogate of secondary organic aerosol

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    Ice nucleation abilities of surface collected mineral dust particles from the Sahara (SD) and Asia (AD) are investigated for the temperature (T) range 253–233 K and for supersaturated relative humidity (RH) conditions in the immersion freezing regime. The dust particles were also coated with a proxy of secondary organic aerosol (SOA) from the dark ozonolysis of α-pinene to better understand the influence of atmospheric coatings on the immersion freezing ability of mineral dust particles. The measurements are conducted on polydisperse particles in the size range 0.01–3 µm with three different ice nucleation chambers. Two of the chambers follow the continuous flow diffusion chamber (CFDC) principle (Portable Ice Nucleation Chamber, PINC) and the Colorado State University CFDC (CSU-CFDC), whereas the third was the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) cloud expansion chamber. From observed activated fractions (AFs) and ice nucleation active site (INAS) densities, it is concluded within experimental uncertainties that there is no significant difference between the ice nucleation ability of the particular SD and AD samples examined. A small bias towards higher INAS densities for uncoated versus SOA-coated dusts is found but this is well within the 1σ (66 % prediction bands) region of the average fit to the data, which captures 75 % of the INAS densities observed in this study. Furthermore, no systematic differences are observed between SOA-coated and uncoated dusts in both SD and AD cases, regardless of coating thickness (3–60 nm). The results suggest that any differences observed are within the uncertainty of the measurements or differences in cloud chamber parameters such as size fraction of particles sampled, and residence time, as well as assumptions in using INAS densities to compare polydisperse aerosol measurements which may show variable composition with particle size. Coatings with similar properties to that of the SOA in this work and with coating thickness up to 60 nm are not expected to impede or enhance the immersion mode ice nucleation ability of mineral dust particles.ISSN:1680-7375ISSN:1680-736
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