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Contains fulltext : 119451.pdf (author's version ) (Open Access) We describe a system that estimates when an event is going to happen from a stream of microtexts on Twitter referring to that event. Using a Twitter archive and 60 known football events, we train machine learning classifiers to map unseen tweets onto discrete time segments. The time period before the event is automatically segmented; the accuracy with which tweets can be classified into these segments determines the error (RMSE) of the time-to-event prediction. In a cross-validation experiment we observe that support vector machines with chi-squared feature selection attain the lowest prediction error of 52.3 hours off. In a comparison with human subjects, humans produce a larger error, but recognize more tweets as posted before the event; the machine-learning approach more often misclassifies a ‘before’ tweet as posted during or after the event. 25th Belgium-Netherlands Artificial Intelligence Conference (BNAIC-2013), 06 november 2013

We propose a combination of theories about interpersonal stances and politeness to inform virtual agent behaviour in a serious game, aimed at social interaction training in the domain of law enforcement. A pilot study we conducted showed promising results based on which we will refine our model.

Lecanicillium fungicola causes dry bubble disease and is an important problem in the cultivation of Agaricus bisporus. Little is known about the defense of mushrooms against pathogens in general and L. fungicola in particular. In plants and animals, a first attack by a pathogen often induces a systemic response that results in an acquired resistance to subsequent attacks by the same pathogen. The development of functionally similar responses in these two eukaryotic kingdoms indicates that they are important to all multi-cellular organisms. We investigated if such responses also occur in the interaction between the white button mushroom and L. fungicola. A first infection of mushrooms of the commercial A. bisporus strain Sylvan A15 by L. fungicola did not induce systemic resistance against a subsequent infection. Similar results were obtained with the A. bisporus strain MES01497, which was demonstrated to be more resistant to dry bubble disease. Apparently, fruiting bodies of A. bisporus do not express induced resistance against L. fungicola.

The Linked Open Data (LOD) cloud is too big for efficient computation and too heterogeneous for standard materialization techniques to cope with. The purpose of the DataHives system is to solve both of these problems by utilizing swarm intelligence to enhance a curated dataset. The system spawns software agents that traverse the LOD cloud looking for extensions to the curated dataset that are relevant and trusted.

Meloidogyne minor is a small root-knot nematode that causes yellow patch disease in golf courses and severe quality damage in potatoes. It was described in 2004 and has been detected in The Netherlands, England, Wales, Northern Ireland, Ireland and Belgium. The nematode often appears together with M. naasi on grasses. It causes similar symptoms on potato tubers as M. chitwoodi and M. fallax, which are both quarantine organisms in Europe. An accurate identification method therefore is required. This study describes a real-time PCR assay that enables the identification of M. minor after extraction of nematodes from soil or plant samples. Alignments of sequences of rDNA-ITS fragments of M. minor and five other Meloidogyne species were used to design a forward primer Mminor_f299, a specific primer Mminor_r362 and the specific MGB TaqMan probe P_Mm_MGB321. PCR with this primers and probe results in an amplicon of 64 bp. The analytical specificity of the real-time PCR assay was assessed by assaying it on six populations of M. minor and on 10 populations of six other Meloidogyne species. Only DNA from M. minor gave positive results in this assay. The assay was able to identify M. minor using DNA from a single juvenile independent from the DNA extraction method used

Een manier om de kosteneffectiviteit van de detectie van plantenpathogenen te verbeteren is door het tegelijkertijd detecteren van meerdere pathogenen in één monster (zgn. multiplexen). Het gebruik van de Luminex xMAP-technologie biedt een uitgelezen platform om bestaande reagentia in te zetten in een multiplex-setting.

Paardenrassen, die hun oorsprong hebben in Nederland, zijn het Friese paard, het Gelderse paard, de Groninger en het Nederlands trekpaard. Dit verslag over de rol en de toekomst van de Nederlandse paardenrassen beschrijft de domesticatie van het paard en het ontstaan en de ontwikkeling van deze rassen. Daarna komt de huidige paardenfokkerij aan bod. Het verslag wordt afgerond met een hoofdstuk over het belang van het behoud van deze rassen.

Microarray-based detection is limited by variable and inconsistent hybridization intensities across the diversity of probes used in each array. In this paper, we introduce a novel concept for the differentiation of detection targets using duplex melting kinetics. A microarray assay was developed on a PamChip microarray enabling the differentiation of target Phytophthora species using the melting kinetics of probe-target duplexes. In the majority of cases the hybridization kinetics of target and non-target duplexes differed significantly. Analysis of the melting kinetics of duplexes formed by probes with target and non-target DNA was found to be an effective method for determining specific hybridization and was independent of fluctuations in hybridization signal intensity. This form of analysis was more robust than the traditional approach based on hybridization intensity, and enabled the detection of individual Phytophthora species and mixtures thereof

Based on the ITS regions of the ribosomal DNA, specific primer sets were developed for the citrus pathogen Guignardia citricarpa and the common citrus endophyte, G. mangiferae, and tested for their specificity against 37 isolates of G. citricarpa, 29 isolates of G. mangiferae, 10 isolates of related species and other fungi found on citrus. The efficacy of the PCR-detection method for G. citricarpa was approximately 60-70% for lesions without pycnidia, and approximately 90% for lesions with pycnidia. A reliability of 99% can be reached by analysing multiple lesions per sample. An internal control was developed to monitor DNA samples for PCR inhibition; samples with PCR inhibition should be re-examined. Detection by PCR is more rapid than the current five-day incubation method prescribed by the European Union for diagnosis of black spot lesions lacking the diagnostic pycnidia. The latter method had an efficacy of 40-50%, while culturing of suspected lesions had an efficacy of 10%. Species-specific primers and ITS sequence data showed that G. citricarpa can occur as a symptomless endophyte in leaves. This shows that wild and cultivated plants occurring in citrus groves are potential carriers of this quarantine fungus. Application of the presently developed PCR method for the detection of G. citricarpa will enable citrus producing as well as importing countries to prevent further spread of this harmful organism

Hybrid isolates of Phytophthora nicotianae x P. cactorum from five different hosts (Cyclamen, Lavandula, Lewisia, Primula, and Spathiphyllum spp.) were identified by their atypical morphology and their well-defined heterozygous isozyme patterns. The hybrid nature of these isolates was tested by restriction fragment length polymorphism analysis of the internal transcribed spacer (ITS) region of rDNA, generating fragments typical for both P. nicotianae and P. cactorum. In hybrid isolates, polymerase chain reactions (PCR) with primers derived from unique parts of the ITS region (ITS-PCR) of both species yielded a combination of unique amplicons typical of both parental species. Eleven hybrid isolates, three isolates of each parental species and two atypical isolates from Rhododendron and Idesia spp. close to P. cactorum, were analyzed for amplified fragment length polymorphisms (AFLP). Consistent differences in AFLP patterns existed among the hybrid isolates, strongly indicating that these hybrids have arisen from independent hybridization events between P. nicotianae and P. cactorum. The two atypical isolates morphologically resembling P. cactorum were identical to the latter species in ITS-restriction fragment length polymorphism and response to the specific PCR primers but were intermediate between P. nicotianae x P. cactorum and P. cactorum in isozyme profiles and AFLP patterns. Since the introduction of hydroponic systems in greenhouses in the Netherlands, outbreaks of Phytophthora diseases are occurring in previously unaffected host species. This may be due to interspecific hybridization events resulting in novel pathogenic behavior.

Despite prophylactic measures, mainly including vaccination programs and management measures, respiratory disease remains the major cause of economic losses in the bovine species. Choice of treatment is currently mainly based on the clinicians? personal experience. A theoretical method has been proposed earlier to classify this syndrome into four grades of severity: Grade 1, subclinical disease (no treatment); Grade 2, compensated clinical disease (antibiotics only); Grade 3, noncompensated clinical disease (antibiotics + antiinflammatory drugs); and Grade 4, irreversible clinical disease (no treatment). In order to realize this theoretical classification under field conditions, three techniques, each one evaluating the oxygen transport chain at a different level, have been studied and validated, i.e. pulse oximetry, lactate dosage and the lobeline test. Afterwards, measurements were performed on calves suffering from acute respiratory disease and a preliminary classification was established. This novel approach could orientate and economize therapeutic strategies in bovine respiratory disease., The Bovine Practitioner, Vol. 33, No. 1 (1999 January)

This thesis reviews the anti-inflammatory agents that could be available to the practitioner in the future in order to enhance the efficacy of treatment of respiratory diseases in cattle., The Bovine Practitioner, No. 31.1 (1997 January)

Phytophthora fragariae Hickman, which causes strawberry red stele and raspberry root rot, is a quarantine organism for which specific and sensitive detection methods are required to test the health of planting material. Sequences of the internal transcribed spacer regions of the ribosomal gene repeat (rDNA) were used to develop primers for P. fragariae in a nested Polymerase Chain Reaction (PCR). The fungus was readily detected in infected but symptomless roots by nested, but not single-round, PCR. It was also detected in infested water samples obtained from the Dutch General Inspection Service by nested PCR. Detection of PCR products was at least 10-fold more sensitive by PCR-ELISA than by conventional visualisation on agarose gels.

Phytophthora fragariae var. fragariae Hickman, which causes red core disease of strawberry, is a quarantine organism on which a nil tolerance is placed. Detection of the fungus is by a root tip bait test which is highly specific and sensitive but time-consuming (5–6 weeks), has to be done at 12°C and can require some taxonomic experience. Even with the test, detecting red core can still be difficult, especially with early primary infection of propagation beds or infected symptomless resistant cultivars. Moreover, P. cactorum, a closely related fungus, causes crown rot of strawberry. It is not a quarantine organism, typical tolerances of 1␒nfection are allowed, and can confuse diagnosis. Techniques based to the Polymerase Chain Reaction (PCR) are promising alternatives. Various parts of the ribosomal RNA gene repeat (rDNA) have been used to design primers with different specificities: specific PCR primers that can differentiate between P. fragariae and P. cactorum and others designed to detect a wider range of Peronosporales, to which Phytophthora belongs. In nested PCR, combinations of these primers can detect both pathogens with high specificity and sensitivity. Competitive PCR has also been developed to allow quantification of P. cactorum infection in strawberry crowns. With these techniques, P. fragariae was detected in strawberry plants one day after inoculation whereas the symptoms were only visible after one week. Moreover, very low numbers of zoospores could be detected in water samples. The test has been evaluated on samples provided by the inspection services of Scotland and The Netherlands.