Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / According to the River Continuum Concept, in small rivers, corresponding to ~ 80% of river basins, the main energy source for the trophic chain is the material produced in riparian zones, especially leaves. This material goes through the process of decomposition, which is responsible for the nutrients cycling and maintenance of aquatic communities. In this context, the objective of this study is to investigate the effects of physical, chemical and physiological traits of plant species on microbial activity and fragmentation, and as a consequence on decomposition rates. In the first chapter we investigated the activity of Phylloicus fragmentation in relation to food resources with different leaf traits. We found that the shredders have their food activity stimulated by substrate with less amount of lignin, which facilitates fungus conditioning and promotes the palatability of the detritus. In the second chapter, we investigated the feeding preference and assimilation of C3 and C4 carbon by Phylloicus and Aegla longirostri. We found that the shredders consume more the C4 species, but do not alter its isotopic signature and the intense activity of the hyphomycetes in the leaves C4 stimulated the consumption by the shredders. In the third chapter we investigated the effect of nutrient enrichment on soil and water on leaf nutritional quality and decomposition rates. We showed that the fertilized trees promoted leaves more nutritious than leaves of unfertilized trees. In addition, we found that the effect of nutrient enrichment on water was stronger than the nutrient enrichment of leaves in the decomposition process. Within the three chapters, we verified that the activities of the shredders and fungi are influenced by the characteristics of the leaves and are related to the riparian vegetation, especially by C3 carbon. We verified that the structural compounds are determinant for the microbial colonization and consequently for the fragmentation and litter decomposition. We also verified that the enrichment of nutrients in the water may be more important for the process of leaf decomposition than the nutrients in the leaves. / De acordo com a teoria do Contínuo Fluvial, nos pequenos rios florestados, que correspondem a ~80% das bacias hidrográficas, a principal fonte de energia para a cadeia trófica é o material produzido nas zonas ripárias, especialmente folhas. Este material passa pelo processo de decomposição, que é responsável pela ciclagem de nutrientes e manutenção das comunidades aquáticas. Neste contexto, o objetivo deste estudo é investigar os efeitos dos traços físicos, químicos e fisiológicos das espécies vegetais na atividade de microrganismos e invertebrados decompositores, e como consequência nas taxas de decomposição. No primeiro capítulo investigamos a atividade de fragmentação de Phylloicus frente a recursos alimentares com características foliares diferentes. Nós constatamos que os fragmentadores têm sua atividade alimentar estimulada por substrato com menor quantidade de lignina, o que facilita o condicionamento por fungos e promove a palatabilidade do detrito. No segundo capítulo, investigamos a preferência alimentar e assimilação C3 e C4 por Phylloicus e Aegla longirostri. Constatamos que os fragmentadores consomem mais a espécie C4, porém não alteram sua assinatura isotópica. E a intensa atividade dos hifomicetos nas folhas C4 estimulou o maior consumo pelos fragmentadores. No terceiro capítulo investigamos o efeito do enriquecimento de nutrientes no solo e na água na qualidade nutricional das folhas e nas taxas de decomposição. Evidenciamos que as plantas fertilizadas geraram folhas mais nutritivas que as não fertilizadas. Além disso, averiguamos que o efeito do aumento de nutrientes na água foi mais forte do que o efeito de nutrientes das folhas no processo de decomposição. Com os três capítulos verificamos que as atividades dos fragmentadores e fungos são influenciadas pelas características das folhas e estão relacionadas com a vegetação ripária, especialmente por carbono C3. Constatamos que os compostos estruturais são determinantes para a colonização microbiana e por consequência para a fragmentação e decomposição foliar. Verificamos também que o enriquecimento de nutrientes na água pode ser mais importante para o processo de decomposição foliar do que os nutrientes nas folhas.

This research tests the application of job enrichment in a maintenance short-interval-task oriented organization. Data were collected from nine work groups involving twenty-nine employees. Results indicate enrichment in this type of organization is possible. Criteria were established to measure the fit of each work group to the five core job dimensions of skill variety, task identity, task significance, autonomy, and feedback. A strong correlation between core job dimension scores and productivity levels was indicated. A work control program, compatible with job enrichment, is discussed and used to implement job content changes. Manipulation of the job content for poor performing groups with low core job dimension scores has resulted in significant reductions in nonproductive time.

Marriages in South Africa in today’s times were found to be in a critical situation. Statistics have proven that most marriages end in divorce within the first five years of marriage. Although marital preparation and enrichment courses are available in South Africa, no specific course exists that is specifically designed for the needs of young married Afrikaans speaking couples. On the grounds of available information it was decided to determine the needs of young Afrikaans speaking married couples whom are married for 1-5 years. By doing this it will enable us to design a marital enrichment programme that will focus on their specific needs. Young married couples will be encouraged to attend marital enrichment programmes. It will assist the couple not to be overwhelmed by the difficult adjustments married life brings and will provide for positive growth within their relationship. It is encouraging to note that all couples who participated in the research previously attended marital enrichment and/or preparation courses and they all acknowledged that it made a positive contribution to their marriage life. The greatest need that is currently not addressed by marital courses is “The different phases within the marital relationship”. Most couples indicated that they had difficult times during the adjustment phase and specifically after the birth of their first child. Most couples indicated that they are still interested in continuous enrichment to ensure growth and development within their relationship. / MSW, North-West University, Potchefstroom Campus, 2014

Master of Science / Department of Psychology / Mary E. Cain / Previous research has shown that both the environment and psychostimulant use influence dopamine levels via the mesolimbic dopamine pathway. C-fos expression has also been observed following exposure to novel environments and psychostimulants. The present study looked to determine the effects of acute amphetamine exposure on locomotor activity and c-fos expression in the basolateral and central nucleus of the amygdala, for rats raised in either an enriched condition (EC), impoverished condition (IC), or social condition (SC). Rats were reared in either the EC, IC, or SC for 30 days, after which they received an acute amphetamine injection (1.0 mg/kg) and locomotor activity was measured. Following the locomotor test rats were perfused and immunohistochemistry was used to measure c-fos levels in the basolateral and central nucleus of the amygdala. Results showed that EC amphetamine rats had significantly greater locomotor activity compared to EC saline rats. There were no significant group or treatment differences in c-fos expression in the ACe. In the BLA SC amphetamine rats had significantly greater c-fos expression than EC amphetamine rats. Overall, the current study revealed that environmental enrichment and amphetamine do significantly alter locomotor activity and c-fos expression in the BLA.

Marriages in South Africa in today’s times were found to be in a critical situation. Statistics have proven that most marriages end in divorce within the first five years of marriage. Although marital preparation and enrichment courses are available in South Africa, no specific course exists that is specifically designed for the needs of young married Afrikaans speaking couples. On the grounds of available information it was decided to determine the needs of young Afrikaans speaking married couples whom are married for 1-5 years. By doing this it will enable us to design a marital enrichment programme that will focus on their specific needs. Young married couples will be encouraged to attend marital enrichment programmes. It will assist the couple not to be overwhelmed by the difficult adjustments married life brings and will provide for positive growth within their relationship. It is encouraging to note that all couples who participated in the research previously attended marital enrichment and/or preparation courses and they all acknowledged that it made a positive contribution to their marriage life. The greatest need that is currently not addressed by marital courses is “The different phases within the marital relationship”. Most couples indicated that they had difficult times during the adjustment phase and specifically after the birth of their first child. Most couples indicated that they are still interested in continuous enrichment to ensure growth and development within their relationship. / MSW, North-West University, Potchefstroom Campus, 2014

This thesis is an investigation of a doctrine generally known as ‘failure of consideration’, but which I term ‘failure of condition’. I have two principal aims. First, to clarify quite what the doctrine of failure of condition is. Secondly, to explain why it has the effects it does – in particular, why it justifies the response of restitution. The doctrine, at core, concerns conditional transfers: when a transfer is made conditionally, and the condition fails, the transfer can be recovered. For this reason, I term the doctrine ‘failure of condition.’ I investigate the nature of this relationship and argue that the reason why the transfer is conditional is that the agent’s intention to make the transfer was itself conditional. The justification of restitution is a more complex affair than is customarily accepted – but there is a valid justification lurking not far from the surface of orthodoxy. A secondary concern of the thesis is to re-examine an old theory in the field of common mistake, frustration and termination following a breach of contract. It used to be thought that these doctrines could be explained by failure of condition. That theory has fallen out of favour – it seems that no one accepts it today. This rejection rests upon a confusion over the nature of the doctrine of failure of condition. Once the nature of this doctrine has been clarified, we can see how closely the various doctrines align with one another; we can also see where the true difficulty with the failure of condition explanation lies.

No description available.

In this project we investigate the feasibility of detecting the signatures of Pop III stars in metal poor second generation stars and in gas clouds at high redshifts. First, the nucleosynthetic yields of Pair Instability Supernova and how they are manifested in gas clouds are presented. Next, some basic quantities of radio astronomy are explained and the requirements of SKA are shown. Then, the minimum detectable hydrogen column density of SKA for gas clouds at high redhsift is calculated and after that the basic principles of spectroscopy and the requirements of the HiReS instrument of E-ELT are demonstrated. Finally, suggestions about where the observations with HiReS should focus are made.

Thesis (LLM)--Stellenbosch University, 2012. / Includes bibliography / ENGLISH ABSTRACT: It is a general principle of the law of South Africa that an unassisted contract of a minor is unenforceable against the minor. Although it binds the other party, the minor is not bound. The minor will only be bound if the contract is enforced by his guardian, or if the contract is ratified by the child after attaining majority. This implies that the other party is in a rather unfortunate position, since the effectiveness of the contract will remain uncertain until the guardian of the minor decides to enforce or repudiate the contract, or until the minor ratifies it after attaining majority. The other party may not resile from the contract during this interim period. Should it be established that the contract has failed, the question arises to what extent the parties are obliged to return performances made in purported fulfilment of the contract. In terms of the law of South Africa, the prevailing view is that these claims are based on unjustified enrichment. However, the extent of these claims differs. In principle, both parties’ liability will be limited to the amount remaining in its estate, according to the defence of loss of enrichment. But the application of the defence is subject to an exception that does not apply equally to the parties. Had the other party known or should the other party have known that the enrichment was sine causa, yet continued to part with it, he will be held liable for the full enrichment. However, this exception does not apply to the enrichment liability of minors. In other words, whether the minor knew or should have known that the enrichment was sine causa, he would still be allowed to raise the defence of loss of enrichment. Furthermore, the rules applicable to minors’ enrichment liability applies to all minors, and no scope is left to consider the specific circumstances of each minor. It is accepted that there are two competing principles relating to minors’ unassisted contracts. On the one hand, the law must protect the minor from his immaturity and lack of experience. On the other hand, the law must protect the interests of the other party. It will be seen throughout this study that the determination of how to balance these competing principles is not an easy task. The key aim of this thesis is to investigate the principles governing the unwinding of unassisted minors’ contracts in South Africa. A comparison will be made with the principles applied in other legal systems, in order to identify similarities and differences in the approaches and, to establish what underlies the differences in the various approaches. Germany, England and Scotland have been chosen for comparison for various reasons. First, they share some historical roots, and they represent three major legal traditions, namely the civil law, common law and mixed legal systems, of which South Africa also forms part. Secondly, both England and Scotland have experienced recent legislative reform in this regard, which implies that their respective legal systems should be in line with modern tendencies, and consequently they may provide a valuable framework for possible reform in South Africa. In Germany, although mainly regulated by rather older legislation, there have been interesting developments in the determination of consequences of failed contracts. Hellwege has argued that the unwinding of all contracts should be treated similarly, regardless of the unwinding factor. He has also suggested that in order to prevent the accumulation of risk on one party, and to ensure that the risk is placed on the person who is in control of the object, the defence of loss of enrichment should not be available to any party. His reasoning and suggestions is dealt with in more detail in this thesis. This study argues that the current strict approach applied under South African law regarding minors’ unassisted contracts needs to be re-considered. The current approach is dated and is not in line with modern tendencies and legislation. No proper consideration is given to minors’ development into adulthood or personal circumstances of the parties. It is submitted that in the process of re-consideration, some form of acknowledgement must be given to minors’ development towards mature adults. It is submitted that this would be possible by introducing a more flexible approach to regulate the enforceability and unwinding of minors’ unassisted contracts. / AFRIKAANSE OPSOMMING Dit is ‘n algemene beginsel van die Suid-Afrikaanse reg dat ‘n kontrak aangegaan deur ‘n minderjarige sonder die nodige bystand van sy ouer of voog onafdwingbaar is teenoor die minderjarige. Die minderjarige sal slegs gebonde wees indien die kontrak afgedwing word deur sy voog, of indien die minderjarige self die kontrak ratifiseer nadat hy meerderjarig word. Dit impliseer dat die ander party in ‘n ongunstige posisie is, aangesien die werking van die kontrak onseker is totdat die voog besluit om die kontrak af te dwing of te repudieer, of totdat die minderjarige dit ratifiseer nadat hy meerderjarig word. Gedurende hierdie interim periode mag die ander party nie terugtree uit hierdie kontrak nie. Sou dit bepaal word dat die kontrak misluk het, ontstaan die vraag tot watter mate die partye verplig word om prestasies wat reeds gemaak is, terug te gee. In terme van die Suid-Afrikaanse reg is die meerderheidsopinie dat hierdie eise gebaseer is op onregverdige verryking, maar die omvang van die partye se eise verskil. In beginsel is beide partye se aanspreeklikheid beperk tot die bedrag wat steeds in sy boedel beskikbaar is, weens die beskikbaarheid van die verweer van verlies van verryking. Maar die toepassing van die verweer is onderworpe aan ‘n uitsondering wat nie op beide partye geld nie. Indien die ander party geweet het of moes geweet het dat die verryking sine causa was, maar steeds afstand gedoen het van die verryking, sal hy aanspreeklik gehou word vir die volle verryking. Hierdie reel is egter nie van toepassing op die minderjarige se verrykingsaanspreeklikheid nie. Met ander woorde, indien die minderjarige geweet het of moes geweet het dat die verryking sine causa was, en steeds afstand gedoen het van die verryking, sal hy steeds die verweer van verlies van verryking kan opper. Bowendien, die reels van toepassing op minderjariges se verrykingsaanspreeklikheid is van toepassing op alle minderjariges, en geen ruimte word gelaat om die spesifieke omstandighede van elke minderjarige in ag te neem nie. Wanneer ons kontrakte aangegaan deur minderjariges sonder die nodige bystand, oorweeg, word dit algemeen aanvaar dat daar twee kompeterende beginsels van belang is. Aan die een kant moet die reg die minderjarige beskerm teen sy onvolwassenheid en gebrek aan ondervinding. Aan die ander kant moet die reg ook die belange van die ander party beskerm. Dit sal deurlopend in hierdie studie gesien word dat die behoorlike balansering van hierdie twee beginsels nie ‘n maklike taak is nie. Die hoofdoel van hierdie tesis is om die beginsels wat die afdwingbaarheid en ontbinding van minderjariges se kontrakte in Suid-Afrika, wat aangegaan is sonder die nodige bystand van ‘n voog, te ondersoek. ‘n Vergelyking sal getref word met die beginsels wat in ander regstelsels toegepas word, om sodoende die ooreenkomste en verskille te identifiseer, asook om te bepaal wat hierdie verskille onderlê. Duitsland, Engeland en Skotland is gekies as vergelykende jurisdiksies vir verskeie redes, naamlik hulle historiese gebondenheid en die feit dat hulle drie groot regstradisies (die kontinentale regstelsel, die gemenereg en die gemengde regstelsel) verteenwoordig. Bowendien het beide Engeland en Skotland onlangse wetgewende hervorming ondergaan in hierdie sfeer van die reg, wat impliseer dat hierdie regstelsels waarskynlik in lyn sal wees met moderne tendense. Gevolglik kan hulle ‘n waardevolle raamwerk skep waarbinne moontlike hervorming in Suid-Afrika mag plaasvind. Alhoewel Duitsland grotendeels nog deur ouer wetgewing gereguleer word, het dit ook ‘n reeks interessante verwikkelinge ondergaan in die bepaling van die gevolge van kontrakte wat misluk het. Hellwege argumenteer dat die ontbinding van alle kontrakte dieselfde hanteer moet word, ongeag die onderliggende ontbindende faktor. Hy stel ook voor dat om te verhoed dat die risiko op slegs een party geplaas word, en om te verseker dat dit eerder gedra word deur daardie party wat beheer het oor die voorwerp, die verweer van verlies van verryking nie vir enige party beskikbaar moet wees nie. Sy redenering en voorstelle word in meer besonderhede in hierdie studie bespreek. Hierdie studie argumenteer dat die huidige streng benadering wat in Suid-Afrika toegepas word met betrekking tot kontrakte aangegaan deur minderjariges sonder die nodige bystand van ‘n voog, heroorweeg moet word. Die huidige benadering is verouderd en is nie lyn met moderne tendense en wetgewing nie. Bowendien word geen behoorlike oorweging gegee aan minderjariges se ontwikkeling tot volwassenheid nie, en die partye se persoonlike omstandighede word ook nie in ag geneem nie. Daar word argumenteer dat in die proses van heroorweging, ‘n mate van erkenning gegee moet word aan minderjariges se persoonlike ontwikkeling. Daar word verder argumenteer dat ‘n meer buigsame benadering toegepas moet word ten opsigte van die regulering van die afdwingbaarheid en ontbinding van hierdie kontrakte.

Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This study is motivated by existing information on the discontinuity between home literacy practices and school literacy expectations of learners who typically speak a local variety of their mothertongue which is in various ways different from the standardised language of learning and teaching (LoLT). In this particular case the study refers to Afrikaans as a home language and language in education. The main concern is that these learners typically perform below par in standardised South African literacy tests such as the Annual National Assessment (ANA) and the Systemic Evaluation Test. They show slower achievement of literacy milestones, higher school drop-out rates and less achievement of access to higher learning opportunities (Lahire, 1995; Siegel, 2007). A Narrative Enrichment Programme was developed as a means of investigating questions concerning learners’ levels of language awareness, their understanding and use of different spoken and written genres, registers and varieties of Afrikaans (including their own), and their general appreciation for spoken and written forms of language in narrative and in other everyday uses. The purpose of such an investigation is to better understand the apparent discontinuity between home language practices and school language expectations, and to suggest new ways of addressing difficulties that arise in literacy development as a result of such discontinuity. The first part of the Narrative Enrichment Programme provided learners with an enriched reading, listening and writing environment in which they could engage with novel stories and work towards producing their own little books. The second part of the programme consisted of supporting exercises that addressed narrative structure issues that arose in the course of the first part. Specifically, exercises of picture-sequencing, picture-sentence matching and an exercise called Beginning, Middle and End were used to assess how learners recount the various components and the chronology of a story that was presented to them in the form of a set of topically connected pictures, and in a longer narrative that was read to them. Findings show that learners have a keen appreciation of the spoken form of language in that they loved listening to the stories. One group showed special enthusiasm for retelling stories that they had heard at home. Another aspect of the programme to which learners responded enthusiastically, was the activity of illustrating little books; this they appeared to enjoy more than writing them. Enthusiastic responses of learners are attended to because learning is much more likely to proceed successfully if learners enjoy the developmental activities. Levels of linguistic awareness with regards to genre, register and grammatical aspects such as spelling differed from learner to learner. Learners showed varying degrees of dependence on the already familiar genres of fables and fairy tales. Regarding writing conventions they also showed varying degrees of awareness of (e.g.) appropriate punctuation. Interesting examples of regional language use which included phonological awareness of the spoken form are discussed in considerable detail. There were unexpected findings regarding the influence that learners’ life experiences have on their narrative products. The picture sequencing activities reflected learners’ use of familiar everyday events and artefacts rather than reference to ones unfamiliar to them, which were apparently intended in the set of pictures. The rich and varied data that was collected, illustrates theoretical positions regarding the different kinds of habitus learners encounter, the ways in which educational systems privilege some linguistic resources above others, the connections between language and identity, and the ways in which new forms of literacy may assist in better facilitating learners’ emerging literacy and the learning that such literacy should facilitate. / AFRIKAANSE OPSOMMING: Hierdie studie is gemotiveer deur inligting oor die diskontinuïteit tussen tuisgebaseerde geletterdheidspraktyke en skoolgeletterdheidsverwagtinge van leerders wat tipies ’n plaaslike variant van hulle moedertaal praat, wat op verskeie maniere verskil van die gestandardiseerde taal wat as medium van onderrig gebruik word. In hierdie geval verwys die studie na Afrikaans as huistaal en taal-in-onderrig. Die kwessies wat hier ter sake is, is dat hierdie leerders tipies benede die verwagtinge presteer in gestandaardiseerde Suid Afrikaanse geletterdheidstoetse soos die Jaarlikse Nasionale Assessering (ANA) en die Sistemiese Evalueringstoets. Hulle bereik geletterdheidsmylpale stadiger as die norm, vertoon hoër skooluitsaksyfers en minder van hulle behaal toegang tot hoër onderwysgeleenthede (Lahire, 1995; Siegel, 2007). ʼn Narratiewe Verrykingsprogram is ontwikkel as ʼn instrument om vrae te ondersoek wat verband hou met leerders se vlakke van taalbewustheid, hulle begrip en gebruik van verskillende gesproke en geskrewe genres, registers en variante van Afrikaans (insluitend hulle eie), en hul algemene waardering vir gesproke en geskrewe vorme van taal in narratief en in ander alledaagse gebruike. Die doel van so 'n ondersoek is om die ooglopende diskontinuïteit tussen huistaalpraktyke en skooltaalverwagtinge beter te verstaan, en om voorstelle te ontwikkel vir die aanspreek van probleme wat in geletterdheisontwikkeling ontstaan as gevolg van so ʼn diskontinuïteit. Die eerste deel van die Narratiewe Verrykingsprogram het leerders voorsien van 'n verrykte omgewing waarin hulle aktief betrokke kon raak by nuwe verhale en kon werk aan die produksie van hul eie klein boekies. Die tweede deel van die program het bestaan uit ondersteuningsoefeninge wat spesifiek kwessies van narratiefstruktuur wat in die eerste deel na vore gekom het, aangespreek het. Meer spesifiek, prentorganiseringsoefeninge, die verbind van sinne aan illustrasies, en 'n oefening genaamd “Begin, Middel en Einde” is gebruik om na te gaan hoe leerders rekenskap gee van die verskillende komponente en die chronologie van ’n verhaal wat aan hulle voorgehou is in die vorm van ʼn stel tematies verwante illustrasies, en in ʼn langer narratief wat aan hulle voorgelees is. Bevindinge toon dat leerders waardering vir die gesproke vorm van taal het, soos geïllustreer in hulle luistergereedheid as stories voorgelees word. Een groep het entoesiasme getoon vir die oorvertel van stories wat hulle by die huis gehoor het. ’n Ander aspek van die program waarop leerders met entoesiasme gereageer het, was die aktiwiteit van illustrasie van hulle boekies; hulle het kennelik die aanbied van visuele illustrasies meer geniet as die skryfproses. Entoesiasme van leerders is as belangrik beskou omdat leerprosesse baie meer waarskynlik geslaagd sal wees as leerders die ontwikkelingsaktiwiteit geniet. Vlakke van taalbewustheid ten opsigte van genre, register en grammatikale aspekte soos spelling, verskil van een leerder tot ’n volgende. Leerders het verskillende grade van afhanklikheid getoon van die fabel- en sprokiegenres. Betreffende skryfkonvensies het hulle wisselende grade van bewustheid getoon van (bv.) gepaste leestekengebruik. Interessante voorbeelde van die gebruik van streektaal, wat fonologiese bewussyn van die gesproke vorm insluit, word in besonderhede bespreek. Daar was onvoorsiene bevindinge betreffende die invloed wat leerders se lewenservaringe op hulle narratiewe produkte gehad het. Die prentordeningsaktiwiteite het leerders se gebruik van bekende alledaagse gebeure en artefakte gereflekteer; hulle het nie verwys na wat vir hulle onbekend was nie al het die stel prente oënskynlik iets anders beoog as wat die leerders daarvan gemaak het. Die ryk en gevarieerde data wat versamel is, illustreer teoretiese posisies rakende die verskillende soorte habitus waarmee leerders gekonfronteer word, die wyse waarop onderwyssisteme party soorte taalvaardighede bo ander reken, die verbande tussen taal en identiteit, en die maniere waarop nuwe vorme van geletterdheid ingespan kan word om leerders se ontluikende geletterdheid en die leergeleenthede wat sodanige geletterdheid fasiliteer, te bevorder.