During meiosis, homologous chromosomes pair and undergo reciprocal genetic exchange, producing crossovers. This generates genetic diversity and is required for balanced homolog segregation. Despite the critical functions of crossovers, their frequency and distribution varies extensively within and between species. This crossover variation can be caused by trans-modifiers within populations, which encode diffusible molecules that influence crossover formation elsewhere in the genome. This project utilised natural accessions of Arabidopsis thaliana to identify trans-modifying loci underlying crossover variation within the species. I performed Quantitative Trait Loci (QTL) mapping using a fluorescence-based crossover reporter system to measure recombination frequency in a genomic interval on chromosome 3, termed 420. Mapping in a Col-420 × Bur-0 F2 population revealed four major recombination QTLs (rQTLs) that influence crossover frequency. A novel recessive rQTL on chromosome 1 that reduced crossovers within the interval was fine-mapped to a premature stop codon in TATA Binding Protein (TBP)-associated factor 4b (TAF4b) in Bur-0 (taf4b-1). TAF4b is a subunit of the TFIID complex, a multi-protein general transcription factor complex comprising TBP and numerous TAFs that forms a component of the pre-initiation complex that recruits RNA polymerase II to promoters. Transformation-based complementation experiments and the isolation of several independent taf4b alleles provided genetic proof that TAF4b is essential for wild-type levels of crossover within 420. Analysis of the prevalence of the taf4b-1 mutation in the global Arabidopsis accession collection demonstrated its specificity to three accessions in the British Isles. A combination of cytology, genetic analysis using additional fluorescent reporter lines, and sequencing in F2 recombinant populations demonstrated a genome-wide reduction in crossover frequency in taf4b-1. In addition, RNA sequencing identified numerous transcriptional changes in taf4b-1. Both up- and down-regulated gene sets displayed significant enrichment for genes that are predominantly expressed in meiocytes, and several gene ontology terms pertaining to protein modification and meiotic processes. These results further demonstrate the existence of genetic modifiers of crossover frequency in natural populations of A. thaliana, and the characterisation of a novel trans-modifier of recombination, TAF4b. This signifies a novel function for TAF4b in Arabidopsis, and further enhances our understanding of the molecular factors controlling the frequency and distribution of meiotic crossovers in plants.

Thesis (M.Sc.Eng.) / As semiconductor technology has been scaled down, increased variation in process parameters results in the variation of key device parameters, which will change the performance and operation of the integrated circuit. This MSEE thesis involves the study of the effects of process variation on the behavior of an 8-GHz clock generator (synthesizer) designed in the 0.13μm IBM 8HP BiCMOS technology, and the recommendation of changes that could be mader to the design that would make it more tolerant to process variation. The first part of this MS research project has involved the design of the phase-locked loop (PLL). The PLL contains a differential VCO (voltage-controller oscillator), a TPSC-DFF (True Single-Phase Clock D-Flip Flop) based 2/3/4 frequency divider, a phase frequency detector, a charge pump, a low-pass filter, a logic control circuit and several buffers. since 8 GHz is a fairly high frequency for a clock generator in a 0.13μm technology and since high frequency circuit layouts inevitable degenerate the circuit performance, the frequency in the design part must necessarily be even higher than the specification. Therefore, this work combines the use of the known fastest architecture in every individual part. After completing the design of the synthesizer, it was simulated in Cadence, first with schematic-based models, using the IBM 8HP design kit, and was studies with statistical distributions utilized for key device parameters, as provided by the design kit. the layout of the circuit was completed and the simulations were redone using extracted models, based on the layouts, with the statistical parameter distributions included. According to Monte Carlo distribution simulation results, the most sensitive parameters were identified and analyzed. Based on those results, changes to the circuit have been proposed and studied, such as changes in device W and L, number of gate fingers nf, use of device multiplicity m, and/or changes to the basic circuit architecture to attempt to minimize the effects of process variation behavior functionality of the circuit.

BAKGRUND: I bakgrunden har tidigare undersökningar och litteratur tagits upp som berör vikten av en varierad matematikundervisning i relation till elevers lärande. Utöver tidigare undersökningar görs även kopplingar till vår läroplan för det obligatoriska skolväsendet, förskoleklassen och fritidshemmet, Lpo-94. Undersökningen utgår ifrån det socio-kulturella perspektivet.SYFTE: Syftet med undersökningen är att ta del av verksamma lärares erfarenheter gällande en varierad matematikundervisning. Därigenom hoppas jag också att kunna vidga min egen kompetens inom området.3METOD: Undersökningen har ett kvalitativt förhållningssätt där tillväga-gångssättet är en Self report, det vill säga en intervju som skrivs ner av deltagarna.RESULTAT: Respondenternas svar visade på tydliga skäl till varför det är viktigt att variera undervisningen. I sina redogörelser beskrev även respond-enterna flera olika hjälpmedel och aktiviteter som de använder sig av för att hjälpa eleverna i deras lärande.

Cette étude adopte une analyse cognitive et contrastive des métaphores de l'alimentation en arabe tunisien, en français et en anglais. Cette étude a pour objectif la comparaison des métaphores dans leurs cadres culturels tout en analysant l'effet du contexte socioculturel sur la compréhension et l'utilisation de ces métaphores. Cette étude part d'un corpus qui contient des expressions métaphoriques utilisant des termes en rapport avec l'alimentation. Ces termes incluent les différents types d'aliments et la description des expériences accompagnant l'alimentation. Le corpus a été collecté en consultant des dictionnaires pour le français et l'anglais dans les langues étudiées et en enregistrant des communications avec des sujets parlant la langue arabe tunisienne, où ils répondent à des questions portant sur l'utilisation des termes de l’alimentation. L'analyse qualitative du corpus est basée essentiellement sur les correspondances entre les domaines (cross-domain mapping) (Lakoff & Johnson, 1980 ; Lakoff, 1993) l'un des principaux axes sur lesquels la théorie de la métaphore conceptuelle est construite. L'étude est divisée en trois grandes étapes : 1-Une description et l'analyse des différentes métaphores de l'alimentation dans les trois langues tout en essayant d’extraire les différentes métaphores conceptuelles et en expliquant leur rôle en interaction avec la théorie de l’incorporation (embodiment) : Johnson, 1987 ; Lakoff & Johnson, 1999 ; Maalej, 2004) dans la compréhension et l'utilisation de ces métaphores. 2- Une comparaison de ces métaphores en se basant sur le modèle postulé par Kövecses (2005) analysant la variation métaphorique et l'effet du contexte culturel. Ce modèle étudie les différents aspects de variation métaphorique entre langues/cultures. Ces aspects sont les domaines source et cible, les relations entre la source et la cible, les métaphores linguistiques, les correspondances et modèles culturels. 3- Une investigation de l'effet du contexte socioculturel sur la compréhension et l'utilisation des métaphores de l'alimentation a lieu à travers une étude basée sur la décomposition des différentes métaphores étudiées en métaphores simples et métaphores complexes. Ce modèle développé par Yu (2008) démontre à travers une étude comparative des métaphores conceptuelles l’existence d’un filtre culturel qui permet l’apparition ou l’absence de certaines métaphores spécifiques à la langue/culture en question. / This study adopts a cognitive contrastive analysis of English, French and Tunisian Arabic (for short TA) food metaphors corpora. The three main objectives of the present study are: 1) reveal the cognitive tools governing the understanding of food metaphors across the three languages. 2) sort out and compare the different target domains of food in the three languages with a particular focus on universality and variation. 3) address through variation, the impact of the socio-cultural context on metaphors understanding, use, creation and recreation. Investigating the conceptual role of food expressions, the impact of culture and the interaction between mind, body and culture is the common point among the main objectives of the present research. The study started with collecting a corpus of food-related terms used metaphorically in context. The data collection relied on written and spoken material. The corpus was then analysed qualitatively on the basis of the cross-domain mapping. The study investigated the pertinence of food and related practices in conceptualizing abstract experiences and then being a depository of familiar experiences ready for being created and recreated to frame newly abstract domains and situations. By doing so, the present work defined the role of the socio-cultural settings in metaphorical thought and reviewed the ways through which the context shapes metaphor use and understanding.

Although group-living is widespread in animals, the degree of social complexity varies markedly within and among taxa. One important precondition for the evolution of higher forms of social complexity is increasing group size. However, this imposes a challenge: finding sufficient food for growing numbers of individuals. One hypothesis is that the (in)ability to avoid resource competition as group size increases, could partly explain variation in social complexity among vertebrates. Increasingly, evidence suggests that resource competition can be reduced via three forms of individual specialisation. These are foraging niche specialisation, specialisation to a role under division of labour (DoL), and as a mediator of these two, personality variation. Yet few studies have directly investigated the role of these specialisations in mediating the costs of increasing group size in social vertebrates. In this thesis, I first review the evidence to date that specialising to a foraging niche, and/or to a task under DoL, is (1) mediated via personality variation and (2) can be a means of reducing competition, generated by increasing group size, in social species (Chapter 2). Then, using the cooperative breeding chestnut-crowned babbler (Pomatostomus ruficeps) as my model system, I empirically test some of the hypotheses posed in this review, regarding foraging niche specialisation and associations with personality variation. In Chapter 3, I show that babblers do show personality variation in traits likely to facilitate niche segregation, and in Chapter 4 that variation among individuals within groups is sufficient to lead to intragroup niche specialisation. However, I find that the level of variation within groups is not associated with group size. Then in Chapter 5, I show that in a direct measure of foraging niche, there is only limited evidence for intragroup specialisation, and again that any specialisation is not associated with larger group sizes. I therefore find no evidence that niche specialisation is a means through which babblers can overcome the costs of increasing group size. I discuss the implications of these results for the rise of social complexity in this system, and social vertebrates generally.

Mimetics in Japanese comprise both onomatopoeic expressions (phonomimes) and other ideophones (phenomimes; psychomimes), which do not imitate acoustic phenomena. They can appear in various syntactic positions and adopt the syntactic functions of nouns in a referential phrase, predicates, attributes in a noun phrase and adverbs, with the latter being the most common usage. Since the stem of mimetic expressions such as SUTON ("thump"), KIRARI ("flash"), KYAAA ("Aaaah!") or GAN-GAN ("pounding") cannot be altered and common suffixes such as /N/, /RI/ and /Q/ (glottal stop) cannot be inflected, the syntactic function of mimetics in Japanese is determined by their position in the sentence and the particles (postpositions) used to indicate their function within a larger constituent. In colloquial speech, these particles may also be omitted, which sometimes results in the syntactic position being the only indicator of the syntactic function. However, when contrasting the grammatical usage of mimetics in data sources from various speech registers, it becomes apparent that not all mimetics are used with all particles and in all syntactic positions. Moreover, some mimetics may be combined with certain particles in idiomatic contexts, but would be used differently in spontaneous speech. For this reason, it is not surprising that opinions vary greatly when it comes to determining the distribution of individual mimetics, and mimetics as a class. This often results in L2 learners of Japanese being confused by contradictory statements in dictionaries and textbooks, which may not necessarily reflect the actual usage of mimetics in spoken Japanese and thus constitute an obstacle to effective language learning. The focus of this thesis is a description of the variable use of selected mimetics in attributive contexts, to shed light on the factors underlying the variation, and to establish whether a language change has been taking place in recent years. Empirical data collected from dictionaries, corpora, surveys and interviews shows that sociolinguistic factors such as gender, age and media exposure may influence the grammatical preferences of native speakers and their perception of mimetics. For this reason, both linguistic and extra-linguistic factors have to be taken into account in order to establish a grammatical framework for mimetics in Japanese.

Factors affecting flowering time have been extensively studied for decades. Greater understanding of flowering time has wider implications in agriculture and ecology as the trait is crucial to optimising reproductive success. It is best understood in the genetic model Arabidopsis thaliana (Arabidopsis), in which loss and gain of function mutations have identified several pathways that regulate flowering and its response to the environment. This has been complemented by studies of natural variation in flowering. Worldwide accessions of Arabidopsis have been used to identify additional flowering regulators and to examine the evolution of these genes and their potential involvement in adaptation to different environments. One of the most extensively studied pathways is responsible for accelerated flowering in response to an extended period of cold (vernalization). Several studies have attributed a substantial proportion of worldwide variation to the genes FRIGIDA (FRI) and FLOWERING LOCUS C (FLC), both of which are instrumental in conferring sensitivity to vernalization, though other genes have also been found. This study examines flowering time variation locally in populations of Arabidopsis from in and around Edinburgh. It identifies substantial, genetically determined variation in flowering time and in sensitivity to photoperiod and vernalization between local accessions. Variation in FRI and FLC sequences and in their levels of expression were detected in local accessions, but these were able to explain little of the phenotypic variation observed. Hybrids between local accessions showing extreme differences in flowering time or responses to photoperiod and vernalization were therefore used to map genes underlying their differences as quantitative trait loci (QTL). This analysis identified a locus in chromosome 5 that could account for differences in vernalization sensitivity. This region includes the VERNALIZATION INSENSITIVE 3 (VIN3) gene. Sequence differences between VIN3 alleles and their expression in response to vernalization supported the potential involvement of this gene in local flowering time variation.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

La gestion de la consommation d’énergie et de la température est devenue un enjeu crucial dans les systèmes informatiques. En effet, un grand centre de données consomme autant d’électricité qu’une ville et les processeurs modernes atteignent des températures importantes dégradant ainsi leurs performances et leur fiabilité. Dans cette thèse, nous étudions différents problèmes d’ordonnancement prenant en compte la consommation d’énergie et la température des processeurs en se focalisant sur leur complexité et leur approximabilité. Pour cela, nous utilisons le modèle de Yao et al. (1995) (modèle de variation de vitesse) pour la gestion d’énergie et le modèle de Chrobak et al. (2008) pour la gestion de la température. / Nowadays, the enegy consumption and the heat dissipation of computing environments have emerged as crucial issues. Indeed, large data centers consume as muse electricity as a city while modern processors attain high temperatures degrading their performance and decreasing their reliability.. In this thesis, we study various energy and temperature aware scheduling problems and we focus on their complexity and approximability. A dominant technique for saving energy is by prosper scheduling of the jobs through the operating system combined with appropriate scaling of the processor's speed. This technique is referred to as speed scaling in the literature and its theoretical study was initiated by Yao, Demers and Shenker (FOCS'1995). In order to manage the thermal behavior of a computing device, we adaopt the approach of Chrobak, Dürr, Hurand and Robert (AAIM'2008). The main assumption is that some jobs are more CPU intensive than others and more heat is generated during their execution. Moreover, the cooling of a computing device occurs by introducing appropriate idle periods.

Idioms play an important role in language acquisition but learners do not have sufficient time to learn all of them. Therefore, learners need to focus on the most frequently occurring idioms, which can be determined by corpus searches. Building off previous corpus studies, this study generated a comprehensive list of English idioms by combining lists from several sources and developed a methodology for organizing and sorting idioms within the list. In total, over 27,000 idiom forms were amalgamated and a portion of the list was compiled, which featured 2,697 core idioms and 5,559 variant idiom forms. It was found that over 35% of idioms varied structurally and thirteen types of idiom variation were highlighted. Additionally, issues concerning idiom boundaries were investigated. These results are congruent with previous findings which show that variation is a commonly occurring element of idioms. Furthermore, specific problematic elements for future corpus searches and English language learners are identified.