京都大学 / 新制・課程博士 / 博士(医学) / 甲第25192号 / 医博第5078号 / 京都大学大学院医学研究科医学専攻 / (主査)教授 村川 泰裕, 教授 斎藤 通紀, 教授 李 聖林 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

[pt] A presente dissertação tem como objetivo analisar a quantificação do lucro da intervenção, partindo da convicção de que a utilização indevida do direito de um terceiro não pode jamais ser um bom negócio. Inicialmente, será demonstrado que o enriquecimento sem causa é o instituto mais adequado para lidar com situações em que uma pessoa se beneficia injustamente à custa de outra. Serão minuciosamente analisados os critérios que precisam ser atendidos para que se caracterize esse tipo de enriquecimento, como o aumento patrimonial do interveniente, a obtenção da vantagem à custa de outrem, a ausência de justa causa e a subsidiariedade do instituto. Em seguida, serão explorados os métodos objetivos para calcular o valor que deve ser devolvido ao titular do direito violado, apontando a inaplicabilidade da teoria do duplo limite aos casos de lucro da intervenção, bem como as razões pelas quais os valores pagos a título de reparação de danos extrapatrimoniais não devem ser abatidos do montante a ser restituído. Sustenta-se, ainda, a inadequação de compensar o lucro com o dano dentro do contexto de enriquecimento sem causa. Por fim, será discutido o papel da boa-fé e da má-fé na conduta do interventor, onde o trabalho explorará as divergências na doutrina sobre o tema, concluindo que se o interventor age de boa-fé deve restituir o valor de mercado da vantagem obtida e o lucro da intervenção deve ser repartido entre o interventor e o titular de direito, de forma proporcional à contribuição de cada um. Quanto à má-fé, conclui-se que, além do valor devido pelo uso do bem, o interventor deve restituir todo o lucro obtido com a intervenção. Essa abordagem proporcionará uma análise detalhada dos aspectos legais e éticos envolvidos na quantificação do lucro da intervenção, contribuindo para uma compreensão mais profunda do tema no contexto do Direito brasileiro. / [en] This dissertation aims to analyze the quantification of the disgorgement of profits, based on the conviction that the improper use of a third party s right can never be a good deal. Initially, it will be demonstrated that unjust enrichment is the most appropriate institute for dealing with situations in which one person benefits unfairly at the expense of another. The criteria that need to be met in order to characterize this type of enrichment will be thoroughly analyzed, such as the increase in the intervening party s assets, obtaining the advantage at the expense of others, the absence of just cause and the subsidiarity of the institute. Next, objective methods will be explored to calculate the amount that must be returned to the holder of the violated right, pointing out the inapplicability of the double limit theory to cases of profit from intervention, as well as the reasons why the amounts paid as reparation of moral damages must not be deducted from the amount to be refunded. It is also argued that it is inappropriate to compensate profit for damage within the context of unjust enrichment. Finally, the role of good faith and bad faith in the intervenor s conduct will be discussed, where the work will explore the divergences in the doctrine on the subject, concluding that if the intervenor acts in good faith he must restore the market value of the advantage obtained and the profit from the intervention must be shared between the intervener and the right holder, in proportion to the contribution of each one. As for bad faith, it is concluded that, in addition to the amount due for the use of the asset, the intervener must refund all the profit obtained from the intervention. This approach will provide a detailed analysis of the legal and ethical aspects involved in quantifying the profit from the intervention, contributing to a deeper understanding of the topic in the context of Brazilian Law.

In recent years, the enthalpy raise hot channel factor limit has decreased significantly due to the power upgrade of Ringhals 4 and the use of shielding fuel assemblies. The shielding fuel assemblies task are to reduce the neutron leakage to the reactor vessel and in that way extend the reactor lifetime. This is achieved by replacing a few fuel rods with steel rods. Experiences from the last fuel cycles show that the core design procedure has been hampered because of this and that it’s hard to stay under the design limit. A way to overcome this problem and to improve the fuel economy is to introduce the use of radial enrichment distribution in the fuel assembly. This master thesis shows, through a case study of three fuel cycles at Ringhals 4,  that the internal peaking factor can be improved by roughly 2–3 % and that the maximum enthalpy raise hot channel factor can be improved by about 2.0–2.5 % if the fuel assemblies contain three different levels of enrichments instead of currently one. This can be achieved without any noticeable decrease in cycle length. / Genom en fallstudie av tre driftcykler för Ringhals 4 visar den här rapporten att max FΔH under cykeln kan sänkas med 2,0–2,5 % om bränsleknippena radiellt anrikningsoptimeras med minst tre delanrikningar. Totalt under cykeln kan FΔH sänkas med upp till 4 %. Om radiell anrikningsoptimering införs för Vattenfalls PWR:er skulle arbetet med att designa härdarna förenklas och utrymme ges för att ladda reaktorerna på ett mer ekonomiskt sätt.

Face à la complexité significative du domaine mammographique ainsi que l'évolution massive de ses données, le besoin de contextualiser les connaissances au sein d'une modélisation formelle et exhaustive devient de plus en plus impératif pour les experts. C'est dans ce cadre que s'inscrivent nos travaux de recherche qui s'intéressent à unifier différentes sources de connaissances liées au domaine au sein d'une modélisation ontologique cible. D'une part, plusieurs modélisations ontologiques mammographiques ont été proposées dans la littérature, où chaque ressource présente une perspective distincte du domaine d'intérêt. D'autre part, l'implémentation des systèmes d'acquisition des mammographies rend disponible un grand volume d'informations issues des faits passés, dont la réutilisation devient un enjeu majeur. Toutefois, ces fragments de connaissances, présentant de différentes évidences utiles à la compréhension de domaine, ne sont pas interopérables et nécessitent des méthodologies de gestion de connaissances afin de les unifier. C'est dans ce cadre que se situe notre travail de thèse qui s'intéresse à l'enrichissement d'une ontologie de domaine existante à travers l'extraction et la gestion de nouvelles connaissances (concepts et relations) provenant de deux courants scientifiques à savoir: des ressources ontologiques et des bases de données comportant des expériences passées. Notre approche présente un processus de couplage entre l'enrichissement conceptuel et l'enrichissement relationnel d'une ontologie mammographique existante. Le premier volet comporte trois étapes. La première étape dite de pré-alignement d'ontologies consiste à construire pour chaque ontologie en entrée une hiérarchie des clusters conceptuels flous. Le but étant de réduire l'étape d'alignement de deux ontologies entières en un alignement de deux groupements de concepts de tailles réduits. La deuxième étape consiste à aligner les deux structures des clusters relatives aux ontologies cible et source. Les alignements validés permettent d'enrichir l'ontologie de référence par de nouveaux concepts permettant d'augmenter le niveau de granularité de la base de connaissances. Le deuxième processus s'intéresse à l'enrichissement relationnel de l'ontologie mammographique cible par des relations déduites de la base de données de domaine. Cette dernière comporte des données textuelles des mammographies recueillies dans les services de radiologies. Ce volet comporte ces étapes : i) Le prétraitement des données textuelles ii) l'application de techniques relatives à la fouille de données (ou extraction de connaissances) afin d'extraire des expériences de nouvelles associations sous la forme de règles, iii) Le post-traitement des règles générées. Cette dernière consiste à filtrer et classer les règles afin de faciliter leur interprétation et validation par l'expert vi) L'enrichissement de l'ontologie par de nouvelles associations entre les concepts. Cette approche a été mise en 'uvre et validée sur des ontologies mammographiques réelles et des données des patients fournies par les hôpitaux Taher Sfar et Ben Arous. / Facing the significant complexity of the mammography area and the massive changes in its data, the need to contextualize knowledge in a formal and comprehensive modeling is becoming increasingly urgent for experts. It is within this framework that our thesis work focuses on unifying different sources of knowledge related to the domain within a target ontological modeling. On the one hand, there is, nowadays, several mammographic ontological modeling, where each resource has a distinct perspective area of interest. On the other hand, the implementation of mammography acquisition systems makes available a large volume of information providing a decisive competitive knowledge. However, these fragments of knowledge are not interoperable and they require knowledge management methodologies for being comprehensive. In this context, we are interested on the enrichment of an existing domain ontology through the extraction and the management of new knowledge (concepts and relations) derived from two scientific currents: ontological resources and databases holding with past experiences. Our approach integrates two knowledge mining levels: The first module is the conceptual target mammographic ontology enrichment with new concepts extracting from source ontologies. This step includes three main stages: First, the stage of pre-alignment. The latter consists on building for each input ontology a hierarchy of fuzzy conceptual clusters. The goal is to reduce the alignment task from two full ontologies to two reduced conceptual clusters. The second stage consists on aligning the two hierarchical structures of both source and target ontologies. Thirdly, the validated alignments are used to enrich the reference ontology with new concepts in order to increase the granularity of the knowledge base. The second level of management is interested in the target mammographic ontology relational enrichment by novel relations deducted from domain database. The latter includes medical records of mammograms collected from radiology services. This section includes four main steps: i) the preprocessing of textual data ii) the application of techniques for data mining (or knowledge extraction) to extract new associations from past experience in the form of rules, iii) the post-processing of the generated rules. The latter is to filter and classify the rules in order to facilitate their interpretation and validation by expert, vi) The enrichment of the ontology by new associations between concepts. This approach has been implemented and validated on real mammographic ontologies and patient data provided by Taher Sfar and Ben Arous hospitals. The research work presented in this manuscript relates to knowledge using and merging from heterogeneous sources in order to improve the knowledge management process.

Face au vide juridique encadrant leurs rapports patrimoniaux, les ex-conjoints de fait ont fait appel au droit commun dans une tentative de remédier aux iniquités économiques découlant de leur rupture. Les tribunaux québécois ont reconnu le besoin de combler ce vide, et c’est ainsi que le recours en enrichissement injustifié est devenu le choix de prédilection des conjoints appauvris. Ce recours a été façonné par la jurisprudence en remède sur mesure pour les conjoints non mariés. Une panoplie de mesures ont été mises en place par les tribunaux pour alléger le fardeau de preuve de l’appauvri et pour adapter la quantification de l’indemnité aux réalités conjugales. Cela demeure, toutefois, insuffisant et peu adapté aux besoins des ex-conjoints. Variabilité et imprévisibilité des décisions se sont avérées être le corolaire de cette confection jurisprudentielle : résultat de la large discrétion dont jouissent les magistrats dans l’appréciation des conditions et facteurs applicables et fruit d’un législateur muet. Le présent mémoire soulève les lacunes de l’enrichissement injustifié comme palliatif du problème de la rupture conjugale et démontre que la prestation compensatoire n’est pas, en fait, une protection analogue à l’enrichissement injustifié, ni une mesure adéquate pour les conjointes de fait. À notre avis, une approche fonctionnaliste et plus complète doit primer pour favoriser l’atteinte de l’objectif de protection recherché. Dans une société où le mariage n’est souvent pas le résultat d’un choix réfléchi et, surtout, d’une volonté de s’assujettir à ses effets juridiques, une élévation des droits des conjoints de fait au même niveau que ceux des époux prend tout son sens. / Faced with the legal vacuum surrounding their patrimonial relationships, de facto spouses sought remedies within the general rules of obligations to solve the inequities resulting from their separation. Quebec courts have recognized the need to fill this void, thereby rendering actions for unjust enrichment the preferred choice of impoverished spouses. This remedy has been fashioned by case law into a tailor-made remedy for unmarried spouses. A panoply of measures has been put in place by the courts to lighten the burden of proof of the impoverished and to adapt the quantification of the indemnity to conjugal realities. However, this remains insufficient and poorly adapted to the needs of ex-spouses. Variability and unpredictability of decisions have proven to be the corollary of this jurisprudential confection: the result of the broad discretion of the courts in assessing the applicable conditions and factors and the product of a silent legislator. This memoire raises the shortcomings of unjust enrichment as a palliative to the problem of the separation of de facto spouses and demonstrates that the compensatory allowance is not, in fact, analogous to unjust enrichment, nor is it appropriate for de facto spouses. In our opinion, a functionalist and more comprehensive approach must be privileged to help achieve the desired objective of protection. In a society where marriage is often not the result of a considered choice, or of a desire to submit to its legal effects. Granting de facto spouses to the same level of protection as legal spouses would be preferred.

Text in Afrikaans / Die doel van die onderhawige studie is onder meer om loopbaanorientering aan die tersiere student (BSc Agric) teoreties te fundeer. 'n Uitgebreide Europese studiereis is ondemeem met die doel om bestaande loopbaanorienteringsprogramme aan tersiere instansies, veral universiteite, te ondersoek en die effektiwiteit daarvan te evalueer ten einde voortreflikhede te implementeer. In hierdie studie word die loopbaanorienteringsprogram vir BSc (Agric)studente aan die Universiteit van Pretoria wat reeds in 1994 ontwerp en ge'implementeer is, beskryf sowel as die behoeftepeiling wat onder BSc (Agric)-studente (voor en na die implementering van die program), en vennote in die landboubedryf gedoen is. 'n Verdere doel met die studie is om 'n wetenskaplik verantwoorde loopbaanorienteringsverrykingsprogram vir BSc (Agric)-studente aan die Universiteit van Pretoria te begrond, te ontwerp, die implementering daarvan te beskryf en die resultate daarvan te evalueer. Daar is gepoog om beide loopbaanontwikkelings- en studente-ontwikkelingsteoriee te beskryf en uit te le as fundering vir 'n verantwoorde loopbaanorienteringsverrykingsprogram vir tersiere studente. 'n Oorsig en perspektief is gebied op bestaande loopbaanorienteringsprogramme en -inisiatiewe in 'n intemasionale, nasionale en plaaslike konteks. Die verskynsel van die snelveranderende wereld-van-werk is literatuurmatig gepresiseer en die implikasies uitgewys vir die opleiding van en loopbaanorientering aan die student in die Landbouwetenskap. 'n Behoeftepeiling van loopbaan (en lewens-)kundighedeen vaardighede waaroor graduandi moet beskik is gedoen onder BSc (Agric)-studente (v66r en mi programimplementering) en onder vennote in die landboubedryf. Die ontwikkeling, beslaggewing en ,evaluering van 'n loopbaanorienteringsverrykingsprogram vir BSc (Agric)-studente is beskryf en toegelig. 'n Samevatting van die studie is gegee met enkele gemotiveerde aanbevelings wat uit die navorsing voortvloei. Voorstelle is gemaak vir die inisiering van 'n loopbaansentrum vir studente van die Universiteit van Pretoria. / The aim of this study is amongst others to lay the theoretical foundation of career orientation for BSc (Agric)-students. An extensive European study tour was undertaken with the aim of investigating and evaluating existing career orientation programmes and/or student enrichment endeavours at the various tertiary institutions especially universities. The effectiveness of these programmes was evaluated with the aim of utilizing and implementing aspects of them. In this study the career orientation enrichment programme for BSc (Agric)-students that was already designed and implemented at the University of Pretoria in 1994, is described. The needs of the BSc (Agric)-students before and after the implementation of this programme were determined as well as those of the partners in the agricultural industry. Another aim of this study is to describe the foundation, design and implementation of a scientific, accountable career orientation enrichment programme for BSc (Agric)-students at the University of Pretoria and to evaluate the outcome thereof. The various career development and student development theories are elucidated and described as a foundation for an accountable career orientation enrichment programme for tertiary students. An overview is given of career orientation programmes and initiatives in an international, national and local context. The phenomenon of the fast changing world-ofwork is described and defined more precisely through a literature study with reference to the implications for the training of and career orientation regarding the student in the Science of Agriculture. An investigation was done of the career (and life-) skills that graduates have to attain. The needs and views of BSc (Agric)-students (before and after the programme implementation) and partners in the agricultural industry were extracted. A summary is given of the arguments put forward in this thesis together with some recommendations that have emerged from this research. Proposals are made for the initiation of a career centre for students at the University of Pretoria. / Psychology of Education / D. Ed. (Sielkundige Opvoedkunde)

Steroid hormones belong to a group of compounds known as endocrine disruptors. They are hydrophobic compounds and are categorized as natural and synthetic estrogens. Some common household products have been implicated as estrogen mimics. Exposure effects of these compounds are felt by human and wildlife, such reproductive alterations in fish and frogs. They mainly introduced into the environment through veterinary medicines administration to animals and the discharges from wastewater treatment plants (WWTPs). In this study, a new alternative analytical procedure that is simple, rapid and fast for the determination and quantification of five steroidal hormones: estriol (E3), beta estradiol (β-E2), alpha estradiol (α-E2), testosterone (T), progesterone (P) and bisphenol A (BPA) using the High pressure liquid chromatography coupled to a charged aerosol detector (HPLC-CAD). These compounds were studied because of their strong endocrine-disrupting effects in the environment. Under optimum conditions, a linear graph was obtained with correlation coefficient (R2) ranging from 0.9952 - 0.9996. The proposed method was applied to the analysis of water samples from a wastewater plant and the results obtained were satisfactory. The limits of detection (LOD) for the target analytes in wastewater influent was between 0.0002 – 0.0004 μg/L and the limit of quantification (LOQ) was 0.001 μg/L respectively for each of the analytes. Enrichment factors of 148- 258, and extraction efficiency 84- 102% were obtained for the target analytes; relative standard deviations (% RSD) for m = 6 were between 2.8 and 7.6%. The concentration of the EDCs in environment sample was between 0.2 - 2.3 μg/L. / Chemistry / M. Sc. (Chemistry)

Boreal forests are often strongly nitrogen (N) limited. However, human activities are leading to increased N inputs into these ecosystems, through atmospheric N deposition and forest fertilization. N input into boreal forests can promote net primary productivity, increase herbivore and pathogen damage, and shift plant species composition and community structure. Genetic diversity has been suggested as a key mechanism to promote a plant species’ stability within communities in response to environmental change. Within any plant population, specific traits (e.g. growth and defense traits) can vary substantially among individuals, and a greater variation in traits may increase chances for the persistence of at least some individuals of a population, when environmental conditions change. One aspect of plant chemistry that can greatly vary among different genotypes (GTs) are condensed tannin (CTs). These secondary metabolites have been suggested to affect plant performance in many ways, e.g. through influencing plant growth, the interactions of plants with herbivores and pathogens, and through affecting litter decomposition, and hence the return of nutrients to plants. To investigate how genotypic variation in foliar CT production may mediate the effects that anthropogenic N enrichment can have on plant performance and litter decomposition, I performed a series of experiments. For these experiments, aspen (Populus tremula) GTs with contrasting abilities to produce foliar CTs (i.e. low- vs. high-tannin producers) were grown under 3 N conditions, representing ambient N (+0 kg ha-1), upper level atmospheric N deposition (+15 kg ha-1), and forest fertilization rates (+150 kg ha-1). This general experimental set-up was once established in a field-like environment, from which natural enemies were excluded, and once in a field, in which enemies were present. In my first two studies, I investigated tissue chemistry and plant performance in both environments. I observed that foliar CT levels decreased in response to N in the enemy‑free environment (study I), but increased with added N when enemies were present (study II). These opposing responses to N may be explained by differences in soil N availability in the two environments, or by induction of CTs after enemy attack. Enemy damage generally increased in response to N, and was higher in low-tannin than in high-tannin plants across all N levels. Plant growth of high‑tannin plants was restricted under ambient and low N conditions, probably due to a trade-off between growth and defense. This growth constraint for high‑tannin plants was weakened, when high amounts of N were added (study I and II), and when enemy levels were sufficiently high, so that benefits gained through defense could outweigh the costs of defense production (study II). Despite those general responses of low- and high‑tannin producers to added N, I also observed a number of individual responses of GTs to N addition, which in some case were not connected to the intrinsic ability of the GTs to produce foliar CTs. In study III, gene expression levels in young leaves and phenolic pools of the plants that were grown in the enemy‑free environment were studied. This study revealed that gene control over the regulation of the phenylpropanoid pathway (PPP) was distributed across the entire pathway. Moreover, PPP gene expression was higher in high-tannin GTs than in low‑tannin GTs, particularly under ambient N. At the low N level, gene expressions declined for both low- and high-tannin producers, whereas at the high N level expression at the beginning and the end of the PPP was upregulated and difference between tannin groups disappeared. Furthermore, this study showed that phenolic pools were frequently uncorrelated, and that phenolic pools were only to some extent related to tannin production and gene expression. In study IV, I investigated the decomposability of litter from the field plants. I found that N enrichment generally decreased mass loss, but there was substantial genetic variation in decomposition rates, and GTs were differentially responsive to added N. Study IV further showed that CTs only had a weak effect on decomposition, and other traits, such as specific leaf area and the lignin:N ratio, could better explain genotypic difference in mass loss. Furthermore, N addition caused a shift in which traits most strongly influenced decomposition rates. Collectively, the result of these studies highlight the importance of genetic diversity to promote the stability of species in environments that experience anthropogenic change. / Boreala skogar är ofta mycket kväve (N) begränsade. Men mänskliga aktiviteter leder till ökad N tillförsel i dessa ekosystem, både genom depostition av N från atmosfären och skogsgödsling. N-tillförsel i boreala skogar kan främja netto primärproduktionen men även leda till ökade skador från naturliga fiender (herbivorer och patogener) samt skiftningar i växtartsammansättning. Genetisk mångfald har föreslagits som en viktig mekanism för att främja en växtarts stabilitet inom samhällen som upplever miljöförändringar. Inom varje växtpopulation kan specifika egenskaper (t.ex. tillväxt och försvar) varierar kraftigt mellan individer och en större variation i egenskaper kan öka chanserna för att åtminstone några individer från en population överlever ifall miljöförhållandena förändras. En aspekt av växtkemi som i hög grad kan variera mellan olika genotyper (GT) är bladens kondenserade tanniner (KT). Dessa sekundära metaboliter har föreslagits påverka växtens prestationsförmåga på många sätt, t.ex. genom att påverka tillväxt, interaktioner mellan växter och herbivorer eller patogener och genom att påverka förna nedbrytning, och följaktligen återbördandet av näringsämnen till kretsloppet. För att undersöka hur genotypiska variation i KT produktion kan påverka de effekter som antopogent N kan ha på växtens prestationsförmåga och förna nedbrytning, utförde jag en serie experiment. Jag studerade olika asp (Populus tremula) GT med olika förmåga att producera KT (låg- och hög-tannin producenter). Växterna odlades i tre olika N förhållanden, som representerade ambient N nivå (+0 kg ha-1), atmosfärisk N deposition = låg nivå (+15 kg ha-1), och skogsgödsling = hög nivå (150 kg ha‑1). Dessa GT etablerades i en fält-liknande miljö där naturliga fiender uteslutits och i ett fält där naturliga fiender var närvarande. I mina första två studierna undersökte jag vävnadskemi och växternas prestationsförmåga i de båda miljöerna. Jag observerade att KT nivåerna sjönk till följd av N‑tillsats i den fiende-fria miljön (studie I), men ökade med N-tillsats ifall fiender var närvarande (studie II). Dessa motsatta reaktioner på N-tillsats kan förklaras av skillnader i N-tillgång mellan de två odlingsplatserna eller genom ökad KT produktion som respons på angrepp. Skador orsakade av herbivorer och patogener ökade generellt till följd av N‑tillsats och var högre i låg-tannin än i hög‑tannin producerande GT oavsett N‑förhållande. Tillväxten hos växter från hög‑tannin GT begränsades i ambient- och låg N-tillsats förhållanden, troligen på grund av att avvägning mellan tillväxt och försvar förskjutits emot försvar. Den begränsade tillväxten i hög-tannin växter minskade om stora mängder N tillsattes (studie I och II) och om antalet fiender var tillräckligt högt så att nyttan av försvaret kunde uppväga kostnaderna för försvarsproduktionen (studie II). Trots dessa generella respons hos låg- och hög-tannin GT till följd av N‑tillsats observerade jag även ett antal individuella respons hos GT som i vissa fall var orelaterade till växters förmåga att producera KT. I studie III undersöktes genuttrycksnivåer och fenolinnehåll i blad från växter som odladats i en miljö där naturliga fiender exkluderats. Denna studie visade att fenylpropanoidsyntesvägen (FPV) regleras genom kontroll av många av de undersökta FPV-generna. Dessutom var FPV genuttryck högre i hög-tannin GT än i låg-tannin GT, särskilt vid ambient N. Vid låg N-tillsats minskade genuttrycket av FPV-gener i både låg- och hög-tannin producenter, medan hög N-tillgång ledde till att gener i början och slutet av FPV uppreglerades och till att skillnaderna mellan tannin grupperna försvann. Dessutom visade studien att de separata fenol-poolerna ofta var okorrelerade med varandra och att fenol-poolerna bara till viss del var korrelerade med KT produktion och FPV-genutryck. I studie IV undersökte jag nedbrytningshastigheten för förnan från fältodlade aspar. Jag upptäckte att N-tillsats generellt minskade viktförlusten men att det fanns en betydande genetisk variation mellan GT och att dessa även var olika mottagliga för tillsatt N. Studie IV visade vidare att KT endast hade en svag effekt på nedbrytning och att andra egenskaper såsom specifik bladyta och lignin:N ratio kunde bättre förklara den genotypiska skillnaden i viktförlust. Dessutom orsakade N‑tillsats en förskjutning av vilka egenskaper som mest påverkade förnans nedbrytningshastighet. Sammanfattningsvis visar mina studier på vikten av genetisk mångfald för att främja växtartens stabilitet i miljöer som upplever antropogena förändringar.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of this study was to investigate and describe the current state of Afrikaans FAL teaching in selected Gr 4 – 6 classes in Western Cape urban schools. This was done by presenting an overview of the literature relevant to FAL teaching and FAL curricula as well as the results from questionnaires and semi-structured interviews with Gr 4 – 6 teachers. This study does not offer a quick-fix solution to the problems in the Afrikaans FAL classrooms, but the researcher believes that the findings will highlight the daily challenges Afrikaans FAL teachers have to face and that all role players will become actively involved in improving the state of Afrikaans FAL teaching in the Western Cape. The relevance of this study lies in the national drive towards the promotion of multilingualism among the general population and especially in education. Feedback from student teachers returning from practice teaching indicated that not enough time is allocated by schools for the instruction of Afrikaans FAL; greatly differing methodologies as well as teaching and learning materials are being used in Afrikaans FAL classes; and learner and teacher Afrikaans proficiency varies from class to class. A theoretical framework for language teaching and learning, a literature study pertaining to first additional language teaching nationally and internationally, and an analysis of South African FAL curricula support the research. Constructivism, social constructivism and teacher knowledge were identified as the underpinning theories for language teaching and learning. The literature study provides an overview of all the major methodologies relevant to FAL teaching and the researcher concluded that there is no single method or approach that will ensure effective FAL teaching, but that teachers should implement an eclectic approach to achieve the best results. This study used a mixed methods approach to generate empirical data; 125 questionnaires, completed by Grade 4 – 6 Afrikaans FAL teachers, provided the quantitative data. For the qualitative strand of the study, semi-structured interviews were conducted with 17 Afrikaans FAL teachers. The data of these interviews were used as triangulation, to confirm or disconfirm and elaborate on the results of the questionnaires. One of the major factors impacting negatively on the teaching and learning of Afrikaans FAL is the negative attitude towards Afrikaans among many learners and their parents. Teachers are not equipped with teaching strategies and techniques to manage these negative attitudes. The results show that many teachers still follow a teacher-centred approach to teaching, which is an indication that learners are not given enough opportunities to develop their communicative competence through interaction with others. Another factor affecting Afrikaans FAL teaching negatively is that not all schools implement the prescriptions of the various language policies and curricula as they should. The study also investigated the use of appropriate and relevant learning and teaching support materials (LTSM) in the FAL classroom. The results showed that most teachers still mainly use the textbook as teaching resource. There is a dire need for appropriate Afrikaans LTSM for FAL. The expectation is that, in the age of technology we find ourselves in today, learners’ interest will be stimulated through the use of technological teaching aids. Teachers should therefore have access to, and use, a variety of media and technological teaching aids and be able to integrate them effectively into their language teaching. The findings of the study revealed teachers are caught up in traditional language teaching methods and strategies which do not contribute to the enhancement of learners’ proficiency in the target language. The study also closely examined the different types of knowledge that a language teacher should have. The results showed that the teachers’ knowledge of the curriculum, language policies, language teaching and learning theories as well as methodologies is extremely limited. Therefore a new method or approach is needed, which is why this study recommends that the HEIs and the WCED ensure that initial teacher training programmes and in-service training workshops are upgraded and adapted in order to prepare the teachers adequately to implement the prescribed curriculum using appropriate methodologies and strategies. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die huidige stand van Afrikaans Eerste Addisionele Taal (EAT) onderrig in gekose Gr 4 – 6 klasse in Wes-Kaapse stedelike skole te ondersoek en beskryf. Dit is gedoen by wyse van die aanbieding van ’n oorsig van die betrokke literatuur oor EAT-onderrig en EAT-kurrikula, asook die resultate van vraelyste en semigestruktureerde onderhoude met Gr 4 – 6-onderwysers. Hierdie studie bied nie ’n kitsoplossing vir die probleme in die Afrikaans EAT klaskamers nie, maar die navorser glo dat die bevindinge die uitdagings wat Afrikaans EAT-onderwysers daagliks trotseer, sal beklemtoon en dat alle rolspelers aktief betrokke sal raak om die stand van Afrikaans EAT onderrig in die Wes-Kaap te verbeter. Die toepaslikheid van hierdie studie is gesetel in die nasionale klem op die bevordering van meertaligheid onder die algemene pupliek en veral in die onderwys. Studente terugvoer na die praktiese onderwys dui daarop dat nie genoeg tyd aan die onderrig van Afrkaans EAT in skole bewillig word nie en dat daar ‘n groot verskeidenheid onderrigmetodes en onderrig- en leerhulpmiddels in Afrikaans EAT-klasse aangewend word. Leerders en onderwysers se vaardigheid in Afrikaans wissel ook van klas tot klas. Die navorsing is ondersteun deur ‘n teoretiese raamwerk van taalonderrig en –leer, ‘n literatuurstudie van eerste addisionele taalonderrig, nasionaal sowel as internasionaal, asook ‘n analise van Suid-Afrikaanse EAT-kurrikula. Konstruktivisme. sosio-konstruktivisme en onderwyser kennis is geïdentifiseer as die teoretiese begronding vir taalonderrig en –leer. Die literatuurstudie gee ‘n oorsig van al die belangrike en relevante EAT-metodieke. Die navorser het tot die gevolgtrekking gekom dat nie een enkele metode of benadering effektiewe EAT-onderrig kan verseker nie, maar dat onderwysers ‘n eklektiese benadering behoort te volg om die beste resultate te verseker. Hierdie studie het ‘n gemengde navorsingsbenadering gevolg ten einde empiriese data te genereer. Die kwantatiewe data is ingesamel by wyse van talle vraelyste wat deur Gr 4 – 6 Afrikaans EAT-onderwysers voltooi is. Semi-gestruktureerde onderhoude is met 17 Afrikaans EAT-onderwysers gevoer ten einde die kwalitatiewe data in te samel. Die data van hierdie onderhoude is gebruik as tri-angulasie om die resultate van die vraelyste te bevestig of te weerspreek. Een van die belangrikste faktore wat die onderrig en leer van Afrikaans EAT negatief beïnvloed, is baie leerders en ouers se negatiewe houding teenoor Afrikaans. Onderwysers is nie toegerus met die nodige onderrigstrategieë en –tegnieke om hierdie negatiewe houdings aan te spreek nie. Die resultate wys daarop dat baie onderwysers steeds ’n onderwyser-gerigte benadering volg wat daartoe lei dat die leerders nie genoegsame geleentheide kry om hulle kommunikatiewe vaardighede by wyse van interaksie met ander te ontwikkel nie. ‘n Ander faktor wat Afrikaans EAT-onderrig negatief beïnvloed, is die feit dat nie alle skole die voorskrifte van die verskillende taalbeleide en kurrikula implementeer soos van hulle verwag word nie. Hierdie studie het ook die gebruik van gepaste en relevante onderrig- en leerondersteuningsmateriaal in die EAT-klaskamer ondersoek. Die resultate het daarop gedui dat die meeste onderwysers nog steeds die handboek as belangrikste onderrighulpmiddel gebruik. Daar bestaan ‘n geweldige behoefte na gepaste Afrikaanse onderrig- en leermateriaal vir EAT. In die tegnologiese era waarin ons ons bevind, bestaan die verwagting dat leerders se belangstelling gestimuleer sal word deur die gebruik van tegnologiese onderrigmateriaal. Onderwysers behoort dus toegang te hê tot en ‘n wye verskeidenheid media en tegnologiese onderrigmateriaal te kan gebruik en in staat wees om dit suksesvol te integreer in hulle taalonderrig. Die bevindinge van hierdie studie het gewys dat onderwysers vasgevang is in tradisionele taalonderrigmetodes en –strategieë wat nie bydra tot die ontwikkeling van die leerders se vaardigheid in die teikentaal nie. Die verskillende soorte kennis waaroor ‘n taalonderwyser behoort te beskik is ook onder die vergrootglas geplaas. Die resultate het getoon dat die onderwysers se kennis van die kurrikulum, taalbeleid, taalonderrig en –leerteorieë en metodieke uiters beperk is. Daar is dus ‘n behoefte aan ‘n nuwe metode of benadering en daarom beveel hierdie studie aan dat onderwyseropleidingsprogramme en indiensopleidingswerkswinkels opgegradeer en aangepas word deur die Hoëronderwysinstellings en die WKOD om te verseker dat onderwysers voldoende voorberei word om gepaste metodieke en strategieë toe te pas in die implementering van die voorgeskrewe kurrikula.

Suite à l’abandon agricole, le nouveau milieu forestier en développement est souvent peu diversifié en espèces d’arbres de grande valeur économique. La solution qu’est la plantation d’enrichissement sous couvert doit intégrer l’effet d’interception lumineuse des manchons protecteurs contre le broutage. À cette fin, des ouvertures du couvert par bandes larges de 3, 6 et 9 mètres, combinées à deux manchons protecteurs à petites et grandes mailles et à un témoin, sont comparés. L’expérience analyse l’effet niveaux de lumière sur la croissance de plants de bouleaux jaunes et de chênes à gros fruits allant de 8 à 46 %. L’ouverture de 9 mètres a été la plus avantageuse pour la croissance en hauteur et en diamètre du bouleau jaune, et ce pour les deux types de protections. Le protecteur à petites mailles a limité la croissance de l’espèce dans les trois largeurs d’ouvertures. Le diamètre du chêne à gros fruits a été le plus faible dans cette même protection. Avec une lumière accrue, le diamètre du chêne à gros fruits a augmenté ainsi que la longueur moyenne des branches et la surface foliaire du bouleau jaune. La bonne croissance juvénile ou initiale du bouleau jaune en fait une espèce d’intérêt pour l’enrichissement en forêts. Une ouverture intermédiaire d’une largeur de six mètres est envisageable pour réduire les perturbations et les coûts. La protection de type grandes mailles améliore davantage la croissance que l’autre, sous toutes les tailles d’ouvertures. / Following abandonment of agricultural land, regrowth forests typically show a low diversity of tree species. One possible solution, enrichment underplanting, must consider protection against browsing, which hinders sunlight from reaching the seedlings. We examined the effects on growth of three different widths of strip opening (3, 6 or 9 meters) mixed with two protective sleeves (a small mesh and a large one). In the experiment, light levels reaching seedlings of yellow birch and burr oak range from 8 to 46 %PAR. The nine meters strip was the best to promote diameter and height growth of yellow birch, regardless of the protective sleeves used. The small mesh sleeve produced a smaller growth in all the openings, for both species in diameter and only for yellow birch in height. Burr oak diameter was also reduced by the small mesh protection. With increased light, mean length of branches and leaf area for yellow birch increased, as well as diameter for burr oak. Good growth of yellow birch makes it a species of interest for enrichment planting. A strip opening of 6 meters width could be enough to ensure artificial regeneration of yellow birch, while limiting disturbances and reducing costs. Large mesh sleeve would be best to maximize growth.