Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: This study describes: 1. The isolation and the purification of tissue type plasminogen activator and urokinase plasminogen activator in bovine milk. 2. The biochemical characterisation of tissue type plasminogen activator in bovine milk. 3. An investigation of the influence of the addition of purified tissue type plasminogen activator to ultra high temperature milk, Gouda cheese and yoghurt. / AFRIKAANSE OPSOMMING: Hierdie studie beskryf: 1. Die isolering en suiwering van weefseltipe-plasminogeenaktiveerder en urokinase-plasminogeenaktiveerder in beesmelk. 2. Die biochemiese karakterisering van weefseltipe-plasmingeenaktiveerder in beesmelk. 3. `n Ondersoek na die invloed van die byvoeging van gesuiwerde weefseltipe-plasminogeenaktiveerder by ultra hoë temperatuur melk, Gouda kaas en joghurt.

Los péptidos bioactivos son fragmentos que forman parte de muchas proteínas y que al ser liberados son capaces de regular una serie de procesos biológicos. Para liberarlos, las proteínas son degradas por medio de enzimas digestivas o procesos industriales. Estos péptidos mantienen propiedades antihipertensivas, antimicrobianas, antioxidantes, anticarcinógenas, antinflamatorias, entre otras, que podrían ser aprovechadas para el desarrollo de nuevos fármacos. En este trabajo de investigación, hemos resaltado la utilidad de los péptidos bioactivos como compuestos altamente específicos capaces de contribuir en la mejora de patologías tales como el cáncer, la hipertensión arterial y la enfermedad de Alzheimer. Particularmente, en estas enfermedades, mostramos experimentos in vitro e in vivo con resultados prometedores que motivan a continuar su estudio en humanos. Estos péptidos fueron extraídos del haba de la soja, la leche de vaca y el hígado de atún, evidenciando la disponibilidad de estos en la naturaleza y generando la incógnita de que otros compuestos podrían encontrarse en la flora y fauna del Perú. De la misma forma, se presentan una serie de tecnologías novedosas para el aislamiento de dichos compuestos, entre estas están la precipitación selectiva, la filtración por membrana, la cromatografía de exclusión por tamaño y el isoelectroenfoque. Éstas son escalables, de fácil aplicación, rápidas, no requieren mayor inversión en infraestructura u equipamiento y no necesitan de una gran cantidad de muestra. En conclusión, en este trabajo se demuestra que los péptidos bioactivos guardan gran promesa, en particular en la identificación de compuestos novedosos para el desarrollo de nuevas drogas. Si se genera una alianza en el Perú entre la comunidad científica, la industria y entes públicos financiadores, se podría explotar, responsablemente, la biodiversidad de nuestro país para proceder, en gran escala, con el aislamiento y la identificación masiva de compuestos bioactivos de gran interés a nivel mundial. / Bioactive peptides are fragments that are part of many proteins and which, upon release, are capable of regulating a series of biological processes. To release them, proteins need to be degraded by digestive enzymes or industrial processes. These peptides maintain antihypertensive, antimicrobial, antioxidant, anticarcinogenic, anti-inflammatory properties, amongst others, that could be used to develop new drugs. In this research work, we have highlighted the utility of bioactive peptides as highly-specific compounds capable to contribute in the improvements of pathologies such as cancer, high blood pressure and Alzheimer’s disease. Particularly, in these diseases, we show in vitro and in vivo experiments with promising results that motivate further studies in humans. These peptides were extracted from soy bean, cow milk and tuna liver, evidencing the availability of these in nature and posing the question of all the other compounds that could be found in the flora and fauna of Peru. Moreover, we present a serious of novel technologies to isolate said compounds, amongst these are selective precipitation, membrane filtration, size-exclusion chromatography and isoelectric focusing. These techniques are scalable, easily applied, rapid, do not require significant investment in infrastructure or equipment and do not need a significant amount of sample. In conclusion, in this work we demonstrate that bioactive peptides have great promise in particular in the identification of novel compounds to develop new drugs. If we generate an alliance in Peru between the scientific community, the industry and public financing entities, our country’s biodiversity could be responsibly exploited to proceed, in a big scale, with the massive isolation and identification of bioactive compounds of great interest worldwide / Trabajo de investigación

Cette thèse est une contribution à la description du kmhmouʔ – langue à tradition orale parlée au Laos. Elle présente les caractéristiques générales de cette langue peu décrite dans la région de l’Asie du Sud-Est comme le montre notre référence bibliographique.Le kmhmouʔ, langue isolante, est dépourvue de marqueurs grammaticaux morphologiques. Les mots du kmhmouʔ sont pour la plupart pluricatégoriels et plurifonctionnels : la distinction verbo-nominale se fonde essentiellement sur des critères combinatoires. Les noms sont des noms massifs portant une signification notionnelle, et leur référentialité est conditionnée à la présence de déterminants nominaux (classificateurs, déictiques, quantifieurs et épithètes qualificatives) ; en l’absence de morphologie verbale, le temps, l’aspect et le mode peuvent être soit non-marqués et identifiables par le contexte, marqués par des moyens lexicaux de type adverbial ou circonstanciel, ou marqués par des particules d’origine catégorielle variée (majoritairement verbale), et le plus souvent empruntées aux langues de contact. La description grammaticale s’appuie sur des données spontanées recueillies lors d’un travail de terrain dans les villages kmhmouʔ et à la radio nationale lao pour l’émission en kmhmouʔ. Le travail de terrain a été conduit en kmhmouʔ, et l’analyse et l’interprétation du corpus ont bénéficié du fait que l’auteur est locuteur natif. Une partie du corpus recueilli (1h30 au total) est présenté en annexe, intégralement glosé et traduit en français et en lao. Cette thèse, outre qu’elle rend disponible pour la première fois les données et la grammaire du dialecte du kmhmouʔ de l’Est, ouvre des pistes de réflexion particulièrement intéressantes pour les travaux en typologie des langues isolantes et de la transcatégorialité, ainsi que la réflexion sur le rôle du contact de langue dans la grammaticalisation. / This dissertation is a contribution to the description of Kmhmouʔ, a language with an oral tradition spoken in Laos. It presents the general characteristics of this language, which is among the less described languages of the region of Southeast Asia, as shown by the bibliography. Kmhmouʔ, an isolating language, does not exhibit any grammatical morphology. Words are mostly multi-categorial as regards parts of speech, and multi-functional: the verb-noun distinction is based essentially on combinatory properties of words. Nouns are basically all mass terms bearing a notional meaning, and they become countable and referential by means of determiners (classifiers, deictics, quantifiers and qualifiers); due to the lack of verb morphology, tense, aspect and mood can be either unmarked and identifiable by the context, marked by lexical means (adverbs or adverbial phrases), or marked by particles originating from various parts of speech (mostly verbs), and for the most part borrowed from contact languages.This grammatical description is based on spontaneous data collected during fieldwork in Kmhmouʔ villages and from the Lao national radio (Kmhmouʔ broadcast). The fieldwork was conducted in Kmhmouʔ, and the analysis and interpretation of the corpus benefited from the fact that the author is native speaker of Kmhmouʔ. A significant part of the corpus (1h30 in total) is provided in an appendix, fully glossed and translated into French and Lao.This thesis, besides making data and grammar of the Eastern Kmhmouʔ dialect available for the first time, opens up some new and challenging paths for the study of the typology of isolating languages and transcategoriality, as well as for studies of the role of language contact in grammaticalization.

Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 82-92).

This study involves the modeling and optimization of heterogeneous (HG) blankets for improved reduction of the sound transmission through double-panel systems at low frequencies. HG blankets consist of poro-elastic media with small, embedded masses, operating similar to a distributed mass-spring-damper system. Although most traditional poro-elastic materials have failed to effectively reduce low-frequency, radiated sound from structures, HG blankets show significant potential. A design tool predicting the response of a single-bay double panel system (DPS) with, acoustic cavity, HG blanket and radiated field, later a multi-bay DPS with frames, stringers, mounts, and four HG blankets, was developed and experimentally validated using impedance and mobility methods (IMM). A novel impedance matrix formulation for the HG blanket is derived and coupled to the DPS using an assembled matrix approach derived from the IMM. Genetic algorithms coupled with the previously described design tool of the DPS with the HG blanket treatment can optimize HG blanket design. This study presents a comparison of the performance obtained using the genetic algorithm optimization routine and a novel interactive optimization routine based on sequential addition of masses in the blanket. This research offers a detailed analysis of the behavior of the mass inclusions, highlighting controlled stiffness variation of the mass-spring-damper systems inside the HG blanket. A novel, empirical approach to predict the natural frequency of different mass shapes embedded in porous media was derived and experimentally verified for many different types of porous media. In addition, simplifying a model for poro-elastic materials for low frequencies that Biot and Allard originally proposed and implementing basic elastomechanical solutions produce a novel analytical approach to describe the interaction of the mass inclusions with a poro-elastic layer. A full-scale fuselage experiment performed on a Gulfstream section involves using the design tool for the positions of the mass inclusions, and the results of the previously described empirical approach facilitate tuning of the natural frequencies of the mass inclusions to the desired natural frequencies. The presented results indicate that proper tuning of the HG blankets can result in broadband noise reduction below 500Hz with less than 10% added mass. / Ph. D.

No / Electroretinograms (ERGs) elicited by transient, square-wave L- and M-cone isolating stimuli were recorded from human trichromatic (n=19) and dichromatic (n=4) observers. The stimuli were generated on a 4 primary LED stimulator and were equated in terms of cone modulation (cone contrast = 0.11) and retinal illuminance (12,000 trolands). L- and M-cone isolated ERGs had waveforms similar to those observed for luminance responses. However, M-cone ERGs exhibited a phase reversal in their responses to onset and offset stimuli relative to the L-cone responses. This on-off response reversal was observed in trichromats but not dichromats. Simultaneous counter-phase and in-phase combinations of L- and M-cone isolating stimuli generated responses that reflected chromatic and luminance processing, respectively. We conclude that L- and M-cone specific ERGs provide a measure of how photoreceptors contribute to post-receptoral mechanisms.

本論文旨在透過康德的「孤立法」，尋找審美判斷中美和崇高所包含的先天原理。此一過程，凸顯了以下兩種意涵：1.孤立法是康德「批判」理論中的一個相當重要的方法，所有的先天原理皆因此方法而得以呈顯。本論文第一章分別以康德知識論中的感性與知性，以及實踐哲學中的善的意志為例，先用孤立法證明感性的空間與時間是先天直觀，範疇則是知性的純粹概念。再用同樣的方法，證明善的意志是純粹實踐理性重要的先天知識。2.在康德之前，理性主義和經驗主義哲學家在處理美學問題上所遇到的難題，就前者而言，為了維持美感的普遍性，而將其地位置於知識之下，成為其附庸；後者則為了維護美學獨立之領域而使其喪失了普遍性。本論文第二、三章，藉由對鑑賞判斷及崇高判斷先天原理的探尋，可看出康德對於這些美學問題的處理方式，主要是根據四種樣式的範疇來區分，略述如下，首先就鑑賞而言：(1)由質的範疇引伸出美的「無志趣」問題。(2)由量的範疇引伸出美的普遍性問題。(3)由關係的範疇引伸出美的合的性問題。(4)由「樣式」的範疇引伸出美的必然性問題。至於崇高，則是一種不同於美的情感，康德亦是依據四類範疇來分析其先天原理。基本上，那是一種因構想力無法掌握理性理念，所表現出的「內心激動」。凡此種種，在本論文中皆詳加論述。

Hybrids are common, being found in about 25% of all plant species, but the isolating barriers which preserve species integrity are poorly studied. I investigated this question in the large New Zealand genus Celmisia Cass. (Asteraceae), which hybridises readily in cultivation, but wild hybrids are relatively rare. My study quantitatively tests four potential reproductive isolating barriers in 12 sympatric species of Celmisia found in the Craigieburn Range, inland Canterbury, New Zealand. I examined two potential prezygotic reproductive isolating barriers (flowering phenology and pollinator specialisation), and two potential postzygotic barriers (pre-dispersal seed predation and hybrid seed germination). I used null models to test whether Celmisia species had temporally segregated flowering times, and found that some Celmisia are temporally segregated and thus less likely to form hybrids. I used experimental pair-wise flowering arrays to observe insect visitation to six different Celmisia species pairs. While I found no difference in the overall pollinator community, several insect families showed preferences for some Celmisia species. Furthermore, I found that subtle floral character differences were driving these insect preferences. In particular, I found scape height to be positively associated with insect visitation with taller Celmisia being favoured over shorter species. Insect preferences did not translate into strong floral constancy, therefore indicating that Celmisia flower visitors are likely to be a weak barrier to hybridisation. I reared a range of insect seed predators from field-collected capitula of the hybrid C. x pseudolyallii and both parent species (C. lyallii and C. spectabilis). There was no overall difference in the number of seed-predators per capitulum between hybrid and parent Celmisia taxa. I collected and sowed seeds from three Celmisia hybrids and their parent species in order to test whether hybrids were less fertile than their parent species. I found no evidence to suggest that the seeds of hybrids had lower germination success than those of their parents. Overall I found evidence for only weak prezygotic reproductive isolation and no evidence for postzygotic isolation in the four barriers I examined in Celmisia.

What processes contribute to the evolution of reproductive isolation and the coexistence of interfertile species in the same habitat? This thesis investigates the relative roles of species interactions and intraspecific processes in contributing to reproductive isolation. I combine behavioural and genomic approaches to test hypotheses about what mechanisms maintain the general species boundary between two closely related field cricket species: Teleogryllus oceanicus and T. commodus. These species are a classic study system for sexual communication and readily hybridize in the laboratory, however little is known about species interactions in sympatric populations. I examine patterns of geographic variation in two key sexual traits: calling song and cuticular hydrocarbons (CHCs), and the geographic distribution of genetic variation across a broad sample of allopatric and sympatric populations. I test whether X chromosomes play a pronounced role in population divergence and reproductive isolation. Using close range mating trials and hybridization experiments I identify numerous pre-mating and post-mating barriers between the species. The results indicate that the species are currently reproductively isolated and the pattern of population differentiation does not strongly support contemporary species interactions contributing to phenotypic diversity. Numerous barriers exist between the species, in particular hybrid females are sterile in both cross directions, while hybrid males are relatively fertile. This provides a rare exception to Haldane's rule which is central to many genetic theories of speciation. Established theory predicts that X chromosomes should play a pronounced role in the evolution of both pre- and postzygotic barriers. Contrary to this, I found no evidence that X chromosomes contribute to hybrid female sterility. Moreover, X-linked loci exhibited an unexpected pattern of reduced population differentiation within species, but increased species divergence compared to autosomal loci, which may indicate selective sweeps or sex-biased processes. Taken together, the results suggest that the causes and consequences of X chromosome evolution, in particular among XO taxa, may contradict some of the established theories.

Depuis les travaux de Haiman (1985), l’iconicité de la syntaxe est un sujet à la mode. Ce sujet s’impose particulièrement dans le cas des langues isolantes, à morphologie réduite, où l’ordre des mots est le marqueur principal des structures syntaxiques et se trouve, par là, au centre de la grammaire. L’ordre des mots dans une phrase mime-t-il l’ordre des événements dont on parle ou reflète-t-il l’ordre même du discours, ou est-il arbitraire ? Dans la lignée des travaux sur l’iconicité de Peirce (1930), Haiman (1980, 1985), Tai (1985) etc., nous appelons ‘iconicité temporelle’ le fait que la succession dans le temps, c’est-à-dire dans la chaîne parlée, des constituants d’un énoncé mime la succession des événements dans un monde de référence. Nous avons étendu le champ d’application de cette ‘iconicité temporelle’ des événements aux procès et, de là, aux phases qui les composent. L’objectif de cette thèse est de tenter de ‘faire marcher’ l’idée d’‘iconicité de la séquence 'jusqu’au bout, en partant d’une définition des CVS la plus large possible permettant d’englober toute suite de constituants verbaux ne présentant aucun connecteur. Cela permet d’étendre l’étude à toute séquence de procès décomposable en sous-procès dans le monde de référence ou en sous-événements dans le monde du discours (systèmes protase-apodose hypothétique et temporel). Si l’iconicité est partout, c’est que les marques séquentielles (l’ordre des constituants), avec les informations sur les prédicats (valence et Aktionsart) codées dans le lexique, sont essentielles au fonctionnement des langues isolantes du type du chinois, et que ces marques séquentielles obéissent le plus souvent, au moins dans le cas du chinois, à l’iconicité. / Since Haiman (1985), the iconicity of syntax is a hot topic. This subject is particularly important in the case of isolating languages, with reduced morphology, in which the word order is the main marker of syntactic structures, and, is, therefore, at the centre of grammar. Does the word order in a sentence mimic the order of the events one is speaking of or does it reflect the very order of the discourse, or is it arbitrary? In the line of Peirce (1930), Haiman (1980, 1985), Tai (1985), etc., we call ‘temporal iconicity’ the fact that succession in the time, or in the spoken chain, of constituents of a statement mimics the succession of events in a world of reference. We have extended the scope of this ‘temporal iconicity’ from events to processes and hence to the phases that compose them. The objective of this thesis is to try to develop the idea of ‘iconicity of the temporal sequence’ to its very end, starting from a definition of SVC (serial verb construction) as wide as possible to encompass any sequence of verbal constituents without overt connector. In such a way, it becomes possible to extend the study to any sequence of decomposable processes in sub-tracks in the reference world or in sub-events in the discourse world (conditional and temporal protasis-apodosis systems). If the iconicity is everywhere, it is because that the sequential marks (the constituents order), with the informations about the predicates (valence and Aktionsart) encoded in the lexicon, are essential to the functioning of the isolating languages of the type of Chinese, and that these sequential marks obey most often, at least in the case of Chinese, to iconicity.