Metabolomics : a tool for studying plant biology

In recent years new technologies have allowed gene expression, protein and metabolite profiles in different tissues and developmental stages to be monitored. This is an emerging field in plant science and is applied to diverse plant systems in order to elucidate the regulation of growth and development. The goal in plant metabolomics is to analyze, identify and quantify all low molecular weight molecules of plant organisms. The plant metabolites are extracted and analyzed using various sensitive analytical techniques, usually mass spectrometry (MS) in combination with chromatography. In order to compare the metabolome of different plants in a high through-put manner, a number of biological, analytical and data processing steps have to be performed. In the work underlying this thesis we developed a fast and robust method for routine analysis of plant metabolite patterns using Gas Chromatography-Mass Spectrometry (GC/MS). The method was performed according to Design of Experiment (DOE) to investigate factors affecting the extraction and derivatization of the metabolites from leaves of the plant Arabidopsis thaliana. The outcome of metabolic analysis by GC/MS is a complex mixture of approximately 400 overlapping peaks. Resolving (deconvoluting) overlapping peaks is time-consuming, difficult to automate and additional processing is needed in order to compare samples. To avoid deconvolution being a major bottleneck in high through-put analyses we developed a new semi-automated strategy using hierarchical methods for processing GC/MS data that can be applied to all samples simultaneously. The two methods include base-line correction of the non-processed MS-data files, alignment, time-window determinations, Alternating Regression and multivariate analysis in order to detect metabolites that differ in relative concentrations between samples. The developed methodology was applied to study the effects of the plant hormone GA on the metabolome, with specific emphasis on auxin levels in Arabidopsis thaliana mutants defective in GA biosynthesis and signalling. A large series of plant samples was analysed and the resulting data were processed in less than one week with minimal labour; similar to the time required for the GC/MS analyses of the samples

Building need-based systems for complex hostile situations

The concept of need-based systems is that they are not instantiated until they are brought to use. Such systems are either designed, assembled and instantiated for very concrete needs, alternatively built on speculation. They are used for evaluation, training or for real. In most cases they are not instantiated, though possibly brought into use as needed. How should needs be expressed? Needs are expressed in terms of results and effects. They may be simple or complex, where complex needs can be seen as structured compositions of more basic needs. When facing a hostile situation, it is critical to have predicted all needs necessary for resolving the given assignment. The complexity of needs, and of their interdependencies may appear to be overwhelming, and it is important to find optimal solutions to the problem at hand. What is needed is a knowledge-based conceptual model that describes the inter-relation of needs, predictions and effects. This paper proposes a number of viewpoints and tools to be applied to the construction of need-based systems -- viewing needs as a resource economy, as a non-linear dynamical system, making use of game theory, decision theory, and risk management. Models for needs and predictions, and the ways they are utilized, extends current systems engineering methods

Oppression as a Statutory Ground for Corporate Dissolution

  In the case of a severe accident in a nuclear power plant the reactor may heat up, melt and mix with fuel material to form a substance called corium. In today's nuclear power plants the primary strategy to cool the corium in the event of a severe accident is to flood the ex-vessel cavity with water. The reactions which occur when the liquid metal comes in contact with the water, known as fuel coolant interaction (FCI), can be violent and in the worst case scenario lead to containment failure. In the MISTEE laboratory at KTH, small scale FCI experiments are conducted. This thesis explores how dierent temperatures of liquid tin and water aects the presence of steam explosion. Higher melt superheat and lower water temperature was found to increase the likelihood of steam explosions. Furthermore, a phenomenon was observed, hereby referred to as immediate steam explosion, where the melt exploded immediately upon contact with water. All previous research found states that steam explosion only occurs in the later stages of FCI, thus the results are contradictory. The thesis also includes research on jet breakup in the initial phase of FCI and how it is affected by melt velocity, diameter and temperature as well as water temperature. The experiments performed did not yield data which could be analyzed so no conclusions could be drawn.Om en allvarlig olycka inträffar på ett kärnkraftverk kan reaktorn värmas upp, smälta och bilda en smälta som innehåller bränsleämnen. I dagens kärnkraftverk är den primära strategin för att kyla reaktormaterialet vid en eventuell allvarlig olycka att fylla utrymmet utanför reaktorn med vatten. De reaktioner som uppstår när den smälta metallen kommer i kontakt med vattnet (FCI) kan vara mycket våldsamma och i värsta fall leda till skador på skyddsväggarna. Vid MISTEE på KTH forskar man på reaktionerna i liten skala för att få en ökad förståelse för processerna i FCI. Denna avhandling undersöker sambandet mellan temperaturen på smältan och vattnet och förekomsten av steam explosion. Högre smält temperatur och lägre vattentemperatur visade sig öka sannolikheten för steam explosions. Vidare, ett fenomen observerades, som kommer att refereras till som omedelbar steam explosion, där smältan exploderade direkt vid kontakt med vattnet. All tidigare forskning som hittades pekar på att steam explosions endast sker i senare skeden av FCI. Avhandlingen inkluderar även forskning på uppbrytning av en metall stråle i den initiala fasen av FCI och hur den påverkas av strålens hastighet, diameter och temperatur samt vattnets temperatur. De utförda experimenten resulterade inte i data som kunde analyseras och inga slutsatser kunde dras

Gestures in spatial descriptions

Most studies of gesture production to date have been based on analyses of narrative discourse in face-to-face interaction. Issues such as the relationship between gesture types and the content of speech, as well as the distribution of particular gesture types across given narrative sequences have been investigated. Depictive gestures, e.g., are frequent where the content concerns the description of concrete objects or actions at a narrative level (McNeill 1992). Little is known about the gesture production in other discourse types, however. Just as different discourse genres have oral characteristics, they are likely to result in different gestural characteristics. In this small-scale study, a preliminary analysis is presented of the gestures produced during a spatial description task during which interlocutors were prevented from seeing each other. This paper will discuss the impact of the discourse type on the use of specific gesture types, especially on deictic gestures. In addition, the traditional issue of why speakers gesticulate at all will be briefly addressed in relation to the question of how visibility conditions affect speakers’ gesture production

Urban transport: eliminating blind spots and missing links in the era of the fourth industrial (r)evolution A digital platform and new business model

Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

A Deductive Time Consumption Model for Loading Shortwood

A partly deductive time consumption model was constructed by using earlier knowledge about the importance of grapple size and pile size on the time consumption for loading shortwood. In order to estimate a complete model, only the function for the loading cycle time needs to be known. The potential advantages of this model are an improved understanding of causal relations and the increased efficiency in producing time consumption models. Comparison with conventionally estimated models based on large empirical studies indicated relatively good agreement, concerning both time consumption level and the influence of various loading conditions

Giving language a hand: gesture as a cue based communicative strategy *

All accounts of communicative behaviour in general, and communicative strategies in particular, mention gesture1 in relation to language acquisition (cf. Faerch & Kasper 1983 for an overview). However, few attempts have been made to investigate how spoken language and spontaneous gesture combine to determine discourse referents. Referential gesture and referential discourse will be of particular interest, since communicative strategies in second language discourse often involve labelling problems. This paper will focus on two issues: 1) Within a cognitive account of communicative strategies, gesture will be seen to be part of conceptual or analysis-based strategies, in that relational features in the referents are exploited; 2) It will be argued that communication strategies can be seen in terms of cue manipulation in the same sense as sentence processing has been analysed in terms of competing cues. Strategic behaviour, and indeed the process of referring in general, are seen in terms of cues, combining or competing to determine discourse referents. Gesture can then be regarded as being such a cue at the discourse level, and as a cue-based communicative strategy, in that gesture functions by exploiting physically based cues which can be recognised as being part of the referent. The question of iconicity and motivation vs. the arbitrary qualities of gesture as a strategic cue will be addressed in connection with this

Some reasons for studying gesture and second language acquisition (Hommage à Adam Kendon)

This paper outlines some reasons for why gestures are relevant to the study of SLA. First, given cross-cultural and cross-linguistic gestural repertoires, gestures can be treated as part of what learners can acquire in a target language. Gestures can therefore be studied as a developing system in their own right both in L2 production and comprehension. Second, because of the close link between gestures, language, and speech, learners' gestures as deployed in L2 usage and interaction can offer valuable insights into the processes of acquisition, such as the handling of expressive difficulties, the influence of the first language, interlanguage phenomena, and possibly even into planning and processing difficulties. As a form of input to learners and to their interlocutors alike, finally, gestures also play a potential role for comprehension and learning

Handling discourse: Gestures, reference tracking, and communication strategies in early L2

The production of cohesive discourse, especially maintained reference, poses problems for early second language (L2) speakers. This paper considers a communicative account of overexplicit L2 discourse by focusing on the interdependence between spoken and gestural cohesion, the latter being expressed by anchoring of referents in gesture space. Specifically, this study investigates whether overexplicit maintained reference in speech (lexical noun phrases [NPs]) and gesture (anaphoric gestures) constitutes an interactional communication strategy. We examine L2 speech and gestures of 16 Dutch learners of French retelling stories to addressees under two visibility conditions. The results indicate that the overexplicit properties of L2 speech are not motivated by interactional strategic concerns. The results for anaphoric gestures are more complex. Although their presence is not interactionall

Gesture as a Communication Strategy in Second Language Discourse : A Study of Learners of French and Swedish

Gesture is always mentioned in descriptions of compensatory behaviour in second language discourse, yet it has never been adequately integrated into any theory of Communication Strategies (CSs). This study suggests a method for achieving such an integration. By combining a cognitive theory of speech-associated gestures with a process-oriented framework for CSs, gesture and speech can be seen as reflections of similar underlying processes with different output modes. This approach allows oral and gestural CSs to be classified and analysed within a unified framework. The respective fields are presented in introductory surveys, and a review is provided of studies dealing specifically with compensatory gesture–in aphasia as well as in first and second language acquisition. The experimental part of this work consists of two studies. The production study examines the gestures exploited strategically by Swedish learners of French and French learners of Swedish. The subjects retold a cartoon story in their foreign language to native speakers in conversational narratives. To enable comparisons between learners and proficiency conditions both at individual and group level, subjects performed the task in both their first and their second language. The results show that, contrary to expectations in both fields, strategic gestures do not replace speech, but complement it. Moreover, although strategic gestures are used to solve lexical problems by depicting referential features, most learner gestures instead serve either to maintain visual co-reference at discourse level, or to provide metalinguistic comments on the communicative act itself. These latter functions have hitherto been ignored in CS research. Both similarities and differences can be found between oral and gestural CSs regarding the effect of proficiency, culture, task, and success. The influence of individual communicative style and strategic communicative competence is also discussed. Finally, native listeners’ gestural behaviour is shown to be related to the co-operative effort invested by them to ensure continued interaction, which in turn depends on the proficiency levels of the non-native narrators. The evaluation study investigates native speakers’ assessments of subjects’ gestures, and the effect of gestures on evaluations of proficiency. Native speakers rank all subjects as showing normal or reduced gesture rates and ranges–irrespective of proficiency condition. The influence of gestures on proficiency assessments is modest, but tends to be positive. The results concerning the effectiveness of gestural strategies are inconclusive, however. When exposed to auditory learner data only, listeners believe gestures would improve comprehension, but when learner gestures can be seen, they are not regarded as helpful. This study stresses the need to further examine the effect of strategic behaviour on assessments, and the perception of gestures in interaction. An integrated theory of Communication Strategies has to consider that gestures operate in two ways: as local measures of communicative ‘first-aid’, and as global communication enhancement for speakers and listeners alike. A probabilistic framework is outlined, where variability in performance as well as psycholinguistic and interactional aspects of gesture use are taken into account