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This paper presents an overview of the work carried out at the HMI group of the University of Twente in the domain of multi-party interaction. The process from automatic observations of behavioral aspects through interpretations resulting in recognized behavior is discussed for various modalities and levels. We show how a virtual meeting room can be used for visualization and evaluation of behavioral models as well as a research tool for studying the effect of modified stimuli on the perception of behavior.

One hundred and fourty-four strains of epiphytic micro-organisms, isolated from berries of "Negroamaro ", an apulian grape wine variety, were screened for antagonistic activity against Aspergillus carbonarius and A. niger. These black Aspergilli are considered the main ochratoxigenic species responsible for the accumulation of ochratoxin A in grape. Twenty eight yeast isolates were selected for their inhibitory effects on the above fungal species and assayed by an in vitro nutritional competition test for their antagonistic capacity towards three selected ochratogenic strains. Six yeast isolates belonging to five species, namely 2 isolates of Issatchenkia orientalis and one each of Metschnikowia pulcherrima, Kluyveromyces thermotolerans, Issatchenkia terricola and Candida incommunis species, were finally selected and screened on wounded grape berries for their ability to inhibit the contemporary infection by ochratoxigenic molds and reduce the formation of ochratoxin A. With the exception of the K. thermotolerans isolate, when inoculated at 109 CFU/wound, the other five challenger yeasts reduced the A. carbonarius and A. niger colonization on grape berry (P < 0.05). In particular, the best antagonistic activity was shown by the two I. orientalis isolates. Results suggest that antagonist yeasts with the potential to control of A. carbonarius and A. niger on grape can be found among the microflora associated with the berries.

The creation of large, richly annotated, multimodal corpora of human interactions is an expensive and time consuming task. Support from annotation tools that make the annotation process more efficient is required, especially if the annotation effort involves really large amounts of data. Therefore we investigated how different properties of specific annotation tasks can have an impact on the design of a tool focused on that general class of tasks. In this paper we present our view on the considerations that should drive the design of new tools geared to specific tasks. The main dimensions that we consider are: observation vs interpretation, explicit and implicit input layers, segmentation, feedback, constraints, relations and the content of the annotation elements.

Within the AMI (Augmented Multi-party Interaction) project technologies will be developed that can facilitate human interaction in the context of instrumented meeting rooms, which includes remote participant support and the possibility to browse through past meetings. The project collects data on people engaged in meetings in order to describe, analyze and theorize about meeting behavior and collaborative work. This symposium addresses research methods and techniques used in the AMI project. It deals with the collection of a richly annotated corpus, the design of annotation tools that are focused on specific annotation tasks, methods for user requirements elicitation and browser evaluation, and the observation and interpretation of behavior to obtain recognized behavioral aspects that are visualized and evaluated in a virtual meeting room.

We present work on Obie, an embodied conversational agent framework. An embodied conversational agent, or talking head, consists of three main components. The graphical part consists of a face model and a facial muscle model. Besides the graphical part, we have implemented an emotion model and a mapping from emotions to facial expressions. The animation part of the framework focuses on the combination of different facial movements temporally. In this paper we propose a scheme of combining facial movements on a 3D talking head.

Recent surveys of commercial olive orchards in several Mediterranean countries have shown that Olive leaf yellowing-associated virus (OLYaV) is one of the most widespread viruses in the region. OLYaV, which is currently classified as unassigned virus to the family Closteroviridae, is little known at the molecular (only a sequence of 611 nt is available) and biological level, and its particles have never been observed in the electron microscope. To secure more information on the nucleotide sequence and organization of the viral genome, double stranded RNA (dsRNA) was extracted from a OLYaV-infected plant and used as template for cloning. Rapid amplification of cDNA ends (RACE-PCR) and degenerate oligonucleotide primer (DOP-PCR) protocols were successfully applied to amplify unknown regions of the viral genome. Resulting cDNA clones consisted of a total of 4,605 nucleotides (including the 611 nt previously sequenced), comprising the 3’ terminus of the RdRp gene (39 kDa), the whole 21 kDa, 6 kDa and HSP70 homologue (65 kDa) proteins, and the 5’ terminus of the HSP90-like protein. RdRp and HSP70 sequences were clearly related to (ca 39% and 30% homology, respectively) but phylogenetically different from comparable genes of other members of the family Closteroviridae. Preliminary data on genomic variability using single strand conformation polymorphism (SSCP) were also obtained. Filamentous particles, morphologically similar to those of members of the family Closteroviridae, were observed by electron microscopy in dip preparations from petioles of young leaves of greenhouse-grown OLYaV-infected plants.

M.S. CAPPELLO, G. BLEVE, F. GRIECO, F. DELLAGLIO AND G. ZACHEO. 2004. Aims: Isolation and characterization of indigenous Saccharomyces cerevisiae strains from 12 grape varieties grown in an experimental vineyard of Apulia. Methods and Results: Thirty to 40 colonies from each of the 12 fermentations were obtained at the end stage of spontaneous fermentation. By using morphological and physiological methods and by the PCR analysis of internal transcribed ITS1-5,8S-ITS2, the isolates belonging to Saccharomyces genus were identified. These isolates were further characterized by amplification with S. cerevisiae species- and delta element-specific primers, thus allowing the identification of S. cerevisiae strains selected from each of the 12 fermentations. By means of RFLP analysis of mtDNA, each S. cerevisiae population isolated from a single fermentation appeared to constitute a genetically homogenous group. The comparison of the 12 cultivar-specific mtDNA RFLP patterns, allowed classifying the 12 S. cerevisiae populations into three genetically homogenous groups. The isolated strains fermented vigorously in synthetic and grape juice medium and showed high alcohol and sulphur dioxide (SO2) resistance and low hydrogen sulphite (H2S) production. Conclusions: The molecular analysis, in conjunction with the traditional morphological and physiological methods, was useful in discriminating at strain level the indigenous population of S. cerevisiae present in a vineyard of Apulia. The dominant S. cerevisiae strains identified in the 12 fermented musts showed potentially important oenological characteristics. Significance and Impact of the Study: The characterization of natural S. cerevisiae strains from several typical Italian grapes grown in a restricted experimental vineyard is an important step towards the preservation and exploitation of yeast biodiversity of Apulia, a relevant wine-producing region. The close relationship between the S. cerevisiae strains from different grapes grown in the same vineyard indicated that the occurrence of native strains is representative of the area rather than of the variety of grapes.

The conversion of grape must to wine is a complex biochemical process mediated by highly specialised micro organisms, yeasts and bacteria. The primary role of wine yeast is to catalyse the rapid, complete and efficient conversion of grape sugar into ethanol, carbon dioxide and other minor, but important, metabolites without the development of off-flavours. Winemakers have started to use strains isolated from their own geographical regions to produce wines with peculiar sensorial properties and reproducible quality. Indigenous yeasts with oenological potential are considered autochthonous and are present on the surfaces of undamaged grapes and their success depends on the sum of physical, chemical and biotic factors. In the spontaneous fermentation of grape must, there is a progressive growth pattern of indigenous yeast, with the final stage invariably being dominated by alcohol-tolerant strains of Saccharomyces cerevisiae. Traditionally, the identification and characterisation of yeast species and strains has been based on morphology and physiological properties. In recent years, techniques developed in molecular biology have provided an alternative to these traditional methods and are an important tool in solving industrial problems. An investigation was carried out in order to characterize the yeast population present in the spontaneous fermentation of "Negroamaro" must, an important grape cultivar for the industrialized production of The Salento (south-eastern Italy) wine. The objective of this study was the identification and characterization of natural yeast flora with peculiar technological and oenological properties from "Negroamaro" grapes collected from different vineyards of the The Salento and grown in organic and non-organic conditions. Identification and characterisation of yeast species and strains was carried out by morphological, physiological, biochemical and molecular methods by sampling the micro flora present on grape skin and in the must during spontaneous fermentation, at different stages. The colonies from each sample were selected on the bases of morphological and physiological characteristics and the isolated population was identified at genus level by PCR analysis of the internal transcribed ITS1- 5,8S - ITS2 region. Further identification was carried out by RFLP analysis of the above amplified fragments and of the amplified d interspersed element. On non-organic cultivated grape skin Hanseniaspora uvarum, Metschnikowia pulcherrima and Issatchenkia orientalis were observed, whereas on the skin of organic cultivated grapes Kluyveromyces thermotolerans, Issatchenkia terricola, Candida incomunis and Candida stellata were also found. In the first stage of fermentation (d=1.125 g/l) a population similar to that present on the grape skin was identified. In the following fermentation stages (d= 1070-1.000 g/l) only Saccharomyces cerevisiae was found and a higher number of strains was identified in must from non-organic grapes than in that from organic grapes. The technological properties (ability of the strains to utilise different carbon sources, production of ethanol, glycerol and hydrogen sulphite, surviving in dry conditions, etc.) of the selected S. cerevisiae strains were studied. The dominant S. cerevisiae strains identified in fermented musts showed potentially important enological characteristics.

Spontaneous grape must fermentation, induced by the indigenous micro flora, is believed to be associated with a specific vineyard and to give a distinctive style and quality to that wine. The alcohol-tolerant Saccharomyces cerevisiae strains invariably dominate the latter stage of natural wine fermentation. The S. cerevisiae population and other specific yeasts present in the vineyard niche habitats are considered autochthonous and their involvement in natural fermentation allows the production of wines with particular features in each microclimatic area. The present study was aimed to the individuation of autochthonous yeast strains useful in the improvement of oenological production of Salento, which is a very important wine-producing area of Southern Italy. Grapes were sampled from the most representative areas of Salento region (Brindisi, Salice Salentino, Copertino, Melissano) for "Negroamaro" production and separately subjected to natural fermentation in an experimental scale. The identification of micro biota present during the last step of wine fermentation (>1 °Bé) of Negroamaro grapes, was carried out to select autochthonous yeast strains for industrial wine production. Aliquots of must samples(0.1 ml each) of several dilutions (from 10-1 to 10-6) were spread on YPD agar medium supplemented with ampicillin (100 mg/l) for 3-5 days at 26 °C. As preliminary screening, averages of 1500 colonies for each of the four fermentations were assayed for H2S production on BIGGY agar. The colonies appearing white or light brown (about the 10% of initial 1500 individual clones) were selected and recognized as Saccharomyces cerevisiae by a microbiological screening based on the implementation of the taxonomical keys for identification of yeasts belonging to Saccharomyces genus. All the yeasts analysed were identified as S.cerevisiae. The criterion for S. cerevisiae strain differentiation was provided by the PCR analysis of polymorphism of amplified ? interspersed element sequences, which has been demonstrated to share a similar discriminative power of the mtDNA restriction patterns. Unexpectedly, the obtained results indicated that in all the four analysed Negro Amaro fermentations the S. cerevisiae population was composed by a high number of different strains, thus allowing the identification of a limited number (6) of dominating strains associated with 81 secondary strains. The Negroamaro grape variety was used for microvinification studies with all these yeasts isolates.. The grape must was clarified centrifugation, inoculated with a final concentration of 106 cell ml-1 of pure yeast culture. Transparency and foam production of the fermented products were directly evaluated whilst HPLC analysis was employed to assay glucose, fructose, ethanol, glycerol and acetic acid contents. The results of these technological analyses for the selection of autochthonous starters for Negroamaro wine production will be discussed.

Previous work has shown that the quantity or quality of food affects the degree of asymmetry in bilateral body traits in adult birds, but so far there is no evidence that this is the case in early phases of growth too. I studied asymmetry of tarsus length of nestling Blue Tits (Parus caeruleus) in relation to supplemental feeding. I offered food, in the form of mealworms (Tenebrio molitor) and wax moth (Galleria mellonella) larvae, to the adults during the brood-rearing period. The parents consumed the extra food themselves and fed the brood an amount corresponding to one-third of the brood's total food intake. Food supplementation resulted in reduced asymmetry of nestling tarsus length, indicating that body asymmetry in early phases of life, not only in adult birds, depends on energy or protein intake [KEYWORDS: breeding, developmental stability, Parus caeruleus, supplemental feeding experiment, symmetry]

The GUP1 (Glycerol Uptake Protein 1) gene plays an important role in Saccharomyces cerevisiae utilising glycerol as a carbon source and providing glycerol-mediated recovery from salt stress to deficient strains (Holst et al., 2000). Green fluorescent protein gene (GFP) from Aequora victoria was employed as an in vivo reporter protein when fused to the GUP1 cistron. The GUP1 gene C- and N-terminus was separately tagged with GFP. The two obtained chimerical genes were ligated to the pYES2 vector and the recombinant plasmid used to transform S. cerevisiae W303-1A (wild type) and BHY66 (isogenic to W303-1A but gpd1-, gut1-, gup1- and unable to produce, to metabolise and to import glycerol) strains. The transformation of BHY66 with both GUP1-GFP and GFP-GUP1 chimerical proteins restored wild-type growth under osmotic stress, indicating that both chimerical proteins acted as functional transporters. Localisation at subcellular levels of GUP1-GFP and GFP-GUP1 chimeras was carried out by confocal laser scanning microscopy. In W303-1A cells expressing GFP fused to either 5' or 3' end of GUP1 gene, green fluorescence was localised in two specific compartments, endoplasmic reticulum and plasma membrane. The GUP1 gene was then genetically fused at its C-terminal terminus with the GFP gene. Functional expression, quantification and cellular localisation of GUP1 protein will be discussed.

During 2001, in the Aegean Greek islands of Rodi and Kastellorizo, wild castor bean plants (Ricinus communis L.), showing yellowish vein netting and mottling of the leaves were observed. A virus was isolated by mechanical inoculation from such plants to herbaceous hosts, which based on biological, serological and molecular assays was identified as an isolate of Olive latent virus 2 (OLV-2/CB), virtually indistinguishable from the type strain. The field syndrome was experimentally reproduced in artificially inoculated castor bean seedlings and the virus reisolated, thus fulfilling Koch’s postulates. This is the first report of OLV-2 outside Italy in a natural host other than olive.

Residue levels and degradation rates of chlorpyrifos in orange fruits, orange leaves, and soil were investigated by using three different formulation types, that is, emulsifiable concentrate (EC), wettable granules (WG), and microencapsulates (ME). The pesticide degradation was studied for a period 131 days in orange fruits and for 161 days in orange leaves and soil. The experimental data were used to establish a mathematical model for the decline curves of chlorpyrifos residues as a function of time and to determine the relevant parameters describing such a process. Field trials showed a different degradation rate for EC and WG formulations as compared to ME formulation. For the first two formulations, the dissipation of chlorpyrifos in orange fruits was fast during the first phase and became much slower during the later period. Residue levels of chlorpyrifos from ME remained almost constant for 65 days and then began to decrease. A similar behavior was observed for the three chlorpyrifos formulations on orange leaves and soil. Although microencapsulation of pesticides leads to improved handling safety, additional risks for the consumers, the agriculture workers, and the environment should be taken into account due to prolonged persistence of high residue levels in fruits as well as in leaves and soil.

This dissertation deals with the direct and indirect effects of food availability in different phases of breeding in a small insectivorous bird, the Blue Tit (Parus caeruleus). Previous studies have emphasised the dual nature of food influencing reproductive decisions in birds. On the one hand, food constitutes energy and nutritional resource for the individual. This thesis has focused on the effects of food as a resource in two highly demanding phases: (1) the period of egg laying and (2) the period of brood rearing. On the other hand, food in the laying phase could also function as a cue predicting the best time for rearing the brood. This hypothesis was tested by means of a series of additional feeding experiments in which extra food was offered to the parents throughout the nestling period. Female Blue Tits experiencing additional food during the nestling period laid relatively later the next year than unfed females, controlled for between-year changes in the environment. As a result, those females mis-timed reproduction and raised the brood far from the caterpillar peak the next year. This suggests that food levels experienced during breeding are involved in fine-tuning the timing of breeding the next year. The additional feeding experiments provided the opportunity to investigate the provisioning rules of parents that experience different degrees of food availability. The parents that had access to extra food delivered similar amount of food as control, unfed parents, but with a different combination of feeding frequency and size of prey. They fed the chicks less frequently, but with larger prey items. This suggests that the change in the state of the parents (which spent less time self-feeding because of the food addition) and of the nestlings (because the parents delivered some extra food to them) produced a significant change in the parents' provisioning rules. The availability of more time caused the food-supplemented parents to get access to larger prey, presumably through an increase in selectivity. This is because larger prey could be obtained only by making longer foraging excursions.

A method to find out which species is more likely to start egg laying in a certain nestbox is described. Nestboxes were visited daily and the behaviour of the birds (Great, Blue and Coal Tits) that appeared around the nestbox was observed. The birds' response consisted mainly of giving alarm calls and showing inquisitive behaviour (i.e., approaching the observer and looking at close distance). Proximity of the individual (or the pair) to the nest and inquisitive behaviour of the female bird were found to be associated with nest ownership. Alarm calling and inquisitive behaviour of males were less selective and therefore not diagnostic. Nocturnal check of nestboxes provided useful information about the nest owners, but they were more reliable at late nest-building phases, when the female was closer to egg laying. It is suggested that this observation method may be used in field studies of species breeding in nestboxes or even natural cavities. This work emphasises the importance of observing small details of behaviour as symptoms of the condition 'inside' the individual (motivation).

Oleavirus is a monotypic genus having olive latent virus 2 (OLV-2) as the type species. OLV-2 is transmitted by inoculation of sap but not by aphids. Virus particles have different shape and size, ranging from quasi spherical to bacilliform with length of 37, 43, 48, and 55 nm, respectively, and a diameter of ca. 18 nm. Virions do not contain lipids or carbohydrates and possess a single coat protein species with molecular mass of ca. 24 kDa, which is not required for infectivity. Individual particles contain a single molecule of linear, positive sense ssRNA, constituting ca. 19% of their weight. The genome consists of three functional non polyadenylated, capped, positive sense, single-stranded RNA molecules occurring as three functional species of 3126 nt (RNA1, monocistronic), 2734 nt (RNA2, monocistronic), and 2438 nt (RNA3, bicistronic). Virions encapsidate a fourth RNA species 2078 nt in size (RNA4) with no apparent messenger activity. Virus replication is thought to occur in the cytoplasm possibly in connection with vesicular structures. The strategy of replication encompasses proteolytic processing and subgenomic RNA production. Oleavirus does not have a complete straightforward relationship with any of the current genera in the Bromoviridae, but shows homologies in diverging directions with one genus of the family or another