Quantification of endogenous levels of IAA, IAAsp and IBA in micro-propagated shoots of hybrid chestnut pre-treated with IBA

Endogenous levels of indole-3-acetic acid (IAA), indole-3-acetylaspartic acid (IAAsp) and indole-3-butyric acid (IBA) were measured during the first 8 d of in vitro rooting of rootstock from the chestnut ‘M3’ hybrid by high performance liquid chromatography (HPLC). Rooting was induced either by dipping the basal ends of the shoots into a 4.92-mM IBA solution for 1 min or by sub-culturing the shoots on solid rooting medium supplemented with 14.8- μM IBA for 5 d. For root development, the induced shoots were transferred to auxin-free solid medium. Auxins were measured in the apical and basal parts of the shoots by means of HPLC. Endogenous levels of IAA and IAAsp were found to be greater in IBA-treated shoots than in control shoots. In extracts of the basal parts of the shoots, the concentration of free IAA showed a significant peak 2 d after either root inductive method and a subsequent gradual decrease for the remainder of the time course. The concentration of IAAsp peaked at day 6 in extracts of the basal parts of shoots induced with 14.8-μM IBA for 5 d, whereas shoots induced by dipping showed an initial increase until day 2 and then remained stable. In extracts from basal shoot portions induced by dipping, IBA concentration showed a transient peak at day 1 and a plateau between day 2 and 4, in contrast to the profile of shoots induced on auxin-containing medium, which showed a significant reduction between 4 and 6 d after transferred to auxin-free medium. All quantified auxins remained at a relatively low level, virtually constant, in extracts from apical shoot portions, as well as in extracts from control non-rooting shoots. In conclusion, the natural auxin IAA is the signal responsible for root induction, although it is driven by exogenous IBA independently of the adding conditions

A Qualitative and Quantitative Characterisation of Style in Sign Language Gestures

Abstract. This paper addresses the identification and representation of the variations induced by style for the synthesis of realistic and convincing expressive gesture sequences. A qualitative and quantitative comparison between styled gesture sequences is performed. This comparison leads to the identification of temporal, spatial, and stuctural processes that are described in a theoritical model of sign language. Insights raised by this study are then considered in order to enhance existing gesture specification systems.

Expressive Body Animation Pipeline for Virtual Agent

International audience<p>In this paper, we present our expressive body-gestures animation synthesis model for our Embodied Conversational Agent(ECA) technology. Our implementation builds upon a full body reach model using a hybrid kinematics solution. We describe the full pipeline of our model that starts from a symbolic description of behaviors, to the construction of a set of keyframes till the generation of the whole animation enhanced with expressive qualities. Our approach offers convincing visual quality results obtained with high real-time performance.</p

Multimodal Plan Representation for Adaptable BML Scheduling

In this paper we show how behavior scheduling for Virtual Humans can be viewed as a constraint optimization problem, and how Elckerlyc uses this view to maintain a extensible behavior plan representation that allows one to make micro-adjustments to behaviors while keeping constraints between them intact. These capabilities make it possible to implement tight mutual behavior coordination between a Virtual Human and a user, without requiring to re-schedule every time an adjustment needs to be made

Dissection of chitin-triggered immunity in grapevine

SPEIPMUBCT1EJ4A key aspect of the plant innate immune system is the recognition of invading pathogens. This occurs through pattern recognition receptors (PRRs) within the plasma membrane that detect conserved pathogen signatures, termed pathogen-associated molecular patterns (PAMPs). In Arabidopsis thaliana, the PRR CERK1 is a lysin motif receptor-like kinase (LYK) which has three lysin motifs in the extracellular domain, which are responsible for recognition of chitin released from the cell wall of the invading fungal pathogen, and an intracellular kinase domain which is the ‘‘master switch’’ of the signalling cascade leading to PAMP-triggered immunity. The aim of this research was to investigate the involvement of grapevine LYKs in defence against powdery mildew. In comparison to the five members of the LYK gene family in Arabidopsis, we have identified ten members of this gene family in grapevine (Vitis vinifera), three of which (VvLYK1-1, VvLYK1-2 & VvLYK1-3) are highly homologous to CERK1. The coding sequences for VvLYK1-1, VvLYK1-2 & VvLYK1-3 were cloned behind the 35S promoter and transformed into the Arabidopsis cerk1 mutant. A minimum of 5 positive F3 lines were selected per each construct and tested in response to powdery mildew infection. Only VvLYK1-1 was found to functionally complement the cerk1 mutation by re-establishing the penetration resistance against a non-adapted powdery mildew species. Expression of VvLYK1-1 in the cerk1 mutant background was also demonstrated to restore chitin-induced activation of the MAPK signalling pathway. The VvLYK1 protein was localized in the plasma membrane of onion cells using the biolistic method. These results suggest that VvLYK1-1 plays a key role in PAMP-triggered immunity against to powdery mildew in grapevine. A yeast two-hybrid screen carried out with the kinase domain of VvLYK1-1 identified a U-box E3 ubiquitin ligase which shows high homology to the Arabidopsis PUB13 protein. The possible role of VvPUB13 in modulating perception of chitin by VvLYK1-1 will be discussed

Multimodal plan representation for adaptable BML scheduling

Natural human interaction is characterized by interpersonal coordination: interlocutors converge in their speech rates, smoothly switch speaking turns with virtually no delay, provide their interlocutors with verbal and nonverbal backchannel feedback, wait for and react to such feedback, execute physical tasks in tight synchrony, etc. If virtual humans are to achieve such interpersonal coordination they require very flexible behavior plans that are adjustable on-the-fly. In this paper we discuss how such plans are represented, maintained and constructed in our BML realizer Elckerlyc. We argue that behavior scheduling for Virtual Humans can be viewed as a constraint satisfaction problem, and show how Elckerlyc uses this view in its flexible behavior plan representation that allows one to make on-the-fly adjustments to behaviors while keeping the specified constraints between them intact

An incremental multimodal realizer for behavior co-articulation and coordination

Human conversations are highly dynamic, responsive interactions. To enter into flexible interactions with humans, a conversational agent must be capable of fluent incremental behavior generation. New utterance content must be integrated seamlessly with ongoing behavior, requiring dynamic application of co-articulation. The timing and shape of the agent’s behavior must be adapted on-the-fly to the interlocutor, resulting in natural interpersonal coordination. We present AsapRealizer, a BML 1.0 behavior realizer that achieves these capabilities by building upon, and extending, two state of the art existing realizers, as the result of a collaboration between two research groups

Biostimulation of grapevine and wheat : mode of action and possible agronomic uses

SPEIPMUBDowny mildew, caused by Plasmopara viticola, is one of the most important grape pathogen in Europe and North America. Although the control is traditionally performed with fungicides, the appearance of resistant pathogen populations and the possible adverse effects on human and environment health are spurring the search for alternative means. In the present investigation, two protein hydrolysates of soybean (soy) and casein (cas) origin were successfully tested against P. viticola. On Vitis vinifera cv. Marselan plants, the application of soy and cas reduced the infected leaf surface by 76 and 63%, as compared to the untreated control, respectively. Since both hydrolysates seemed to trigger the plant immunity, we investigated their effect on selected grapevine defense responses. On treated grapevine cell suspensions, a different free cytosolic calcium signature was recorded for each hydrolysate, whereas a similar transient phosphorylation of two MAP kinases of 45 and 49 kDa was observed. These signalling events were followed by transcriptome reprogramming, including the up-regulation of genes encoding pathogenesis-related (PR) proteins and the enzyme stilbene synthase responsible for the biosynthesis of resveratrol, the main grapevine phytoalexin. Liquid chromatography analyses confirmed the production of resveratrol and its dimer metabolites, δ- and ε-viniferins. Overall, soy effect was more pronounced than cas one. Both hydrolysates proved to be able to enhance grapevine immunity against pathogen attack