A MSc thesis which describes a theoretical model for gene replication on circular RNA under prebiotic conditions / The origin of life is one of the most captivating and difficult questions that science has yet to answer. Several different questions remain, including how genetic replication may have begun. Replication is a fundamental property of life that allows for evolution and the long-term survival of life. Non-enzymatic replication should have been present at the origin of life. The RNA world theory proposes that because it can act as both an enzyme and gene, RNA could have performed the function of a replicator at the origin of life. Abiotic chemistry for RNA nucleotides is known, as well as mechanisms for simple but random RNA sequence synthesis. However non-enzymatic replication of RNA sequences which might hold functions, has only achieved mild success. This is in no small part because of replication infidelity between RNA bases, and product inhibition during template directed replication. The rolling circle mechanism found in viroids and some RNA viruses, is a likely way to avoid these issues in the RNA World. Here we present a summary of key topics to origins of life and the RNA world, a deterministic model for rolling circle replication, followed by an original computational model for gene fixation in rolling circle replication. In these simulations we observe the dynamics of populations of protocells, each containing multiple copies of rolling circle RNAs that can replicate non-enzymatically. Selection for speed of replication tends to reduce circles to a minimum length. However, errors provide a natural doubling mechanism that creates strands multiple times the length of the minimal sequence. We show that if a beneficial gene appears in this new space, the longer sequence with the beneficial function can be selected, even though it replicates more slowly. This provides a route for the evolution of longer circles encoding multiple genes. / Thesis / Master of Science (MSc) / The origin of life is a topic that many people are inherently curious about. However, science is only just making progress towards an answer. The first organisms must have been able to replicate. Modern organisms use proteins, DNA, and RNA to do this, however it is unlikely these three molecules could have co-ordinated at the origin of life. A simpler model for replication uses only RNA, which can be both a gene and a catalyst. Here we propose some computational models which study RNA replication. These models simulates strands undergoing rolling circle replication, a method of replication some viruses use which has been suggested to be sustainable at the origin of life. We show that rolling circle replication can create long strands which can have new helpful sequences of RNA. This mechanism could have helped the first organisms achieve better replication and evolution, which is a key characteristic of life.

Thesis (doctoral)--Georg-Augusts-Universität, Göttingen, 1904. / "Inaugural Dissertation zur Erlangung der Doktorwürde der Hohen Philosophischen Fakultät der Georg-Augusts-Universität zu Göttingen." Description based on print version record. Includes bibliographical references.

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The rate of transformation from CaO to Ca(OH)2 during the slaking process is influenced by a number of factors. In this investigation the effects of common ions normally encountered in the slaking water were investigated. It was found that chloride and nitrate ions enhanced the slaking rate, while carbonate, sulphate and phosphate ions retarded the hydration of various limes used in the investigation. The increases and decreases in the degree of hydration correlate with the solubilities of the anions forming more soluble compounds than Ca(OH)2, as well as the solubility constants of the anions that formed less soluble compounds than the hydrated lime. The geological origin of the lime also influenced the slaking of the limes.

Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Includes bibliographical references (p. 112-121). Print copy also available.

The purpose of this study is to promote research into and the development of a non-polemical Islamic conception of Jesus Christ. Before engaging the textual sources the thesis considers in some detail the historical context within which the Quranic discourse about Christ was formulated, and then some post-Quranic Christological disputes between Muslims and Christians. It also considers a broad range of Quranic data about Christ in order to identify certain primary themes in the Quran about him. Then three Quranic verses about Christ and his relationship with the Holy Spirit are analyzed through the interpretations of four classical exegetes. On the basis of their interpretations as well as the general Quranic discourse about Christ this thesis makes a limited number of positive assertions about Christ as well as suggests areas wherein further research on the specifically Islamic view of Christ can be developed.

Submitted in fulfilment for the Honours Degree in the Department of IsiZulu namaGugu in the Faculty of Arts at the University of Zululand, 1997. / Kuthe ngokuntuleka kwemibhalo esitshela kabanzi ngamadlozi kanye nenkolo yobuNaza!etha, ngabona kudingekile ukuba kushicilelwe okuphathekayo nalokhu. Loko kuyonciphisa ukudide}{a okukhulu okukhungethe isizwe esimpisholo. Hleze bayophela abantu abathi kule nkolo kukhonzwa amadlozi. Hleze kuyophela nokuthi umuntu ongasekho emhlabeniumoya omubi, akanamsebenzi walutho. Okubalulekile okumele kuhlale kuzinze ezingqondweni zethu, ukuthi akekho namunye umuntu owavele waqhuma etsheni, nowaqhibuka esidulini. Ilowo nalowo unabo abazali abamlethe kuleli lengabade. Bamnika uthando, bamkhulisa waze waba yilokhu ayikhona. Umuntu okwenzele okukhulu nokuhle kangaka, ungaqaIa ngaphi umlibale? Yikhona loku okuyivuso kithina ukuba sibakhumbule, njengoba bekhunjuIwa nakwezinye izinkolo zezinye izizwe. Akulula ukukuIibala,.nokubalibala ngisho sebemathambo amhIophe".

Vibrio cholerae is a natural inhabitant of aquatic environments and serves as the etiological agent for the severe diarrheal disease, cholera. Cholera epidemics follow a regular seasonal pattern, which account for tens to hundreds of thousands of deaths in a given year. V. choleraenaturally persist between epidemics through entry into a dormant state known as viable but nonculturable (VBNC). Research has shown that V. choleraein this VBNC state experience drastic morphological and metabolic changes, which serve as survival mechanisms until environmental conditions become suitable again. The natural marine ecosystem that V. cholerae inhabitis comprised of a complex combination of biotic and abiotic factors, which influence their growth and survival. Some of these factors include interactions with other marine dwellers and environmental pressures, such as fluctuations in temperature and oxygen concentration. Of great interest, we have currently elucidated the role of oxygen on the classical O395 biotype of V. cholerae. Through this discovery, we are especially interested in the role of oxygen and biotype on V. cholerae persistence and how these variables can influence entry into the VBNC dormant state. Specifically, in this study we will compare culturability between the O395 and N16961 biotypes in both aeration and static (non-aeration environments) at 4°C and 30°C. It is of crucial importance to elucidate the role of abiotic environmental factors involved with entry into this dormant state and to understand how V. cholerae have evolved their genetic mechanisms to persist in their natural environments through comparison of biotypes. Understanding entry into the VBNC state is significant because V. cholerae found in this dormant state remain a threat to the human population due their ability to resuscitate and infect the human host under the appropriate environmental conditions.

Country-of-origin effekten påverkar alla exportföretag. Hur gynnsam effekten är skiljer sig beroende på ursprungsland, bransch och produktkategori. För att ett varumärke ska kunna utvinna en maximal effekt av Sverige som ursprungsland krävs en djup förståelse för hur effekten står sig på olika marknader och hur den bäst förmedlas. Därför syftar studien till att förklara hur svenska exportföretag använder sig av country-of-origin effekten för att stärka sina varumärken. Genom den teoretiska referensramen som berör brand equity och country-of-origin effekten får country-of-origin effekten en tydlig roll i de olika delarna ett varumärke består av. Undersökningen har en kvalitativ undersökningsmetod genom semistrukturerade intervjuer. Tre svenska exportföretag från olika branscher deltar i studien för att undersöka syftet. Analysen inleds med en inomfallsanalys för varje fallföretag som utmynnas till en mellanfallsanalys. Studien visar att svenska exportföretag generellt sett gynnas av country-of-origin effekten, men styrkan av effekten skiljer sig beroende på bransch, marknad och produktkategori. / The country-of-origin effect has an impact on all exporting companies. How favorable the effect is differs based on the country-of-origin, line of business and product category. To extract the maximal effect of Sweden as a country-of-origin, a deep understanding of how the effect influences different markets is needed as well as knowledge of how it is best communicated. Therefore, the study aims to explain how Swedish exporting companies use the country-of-origin effect to strengthen their brands. Through the theories on brand equity and the country-of-origin effect, the country-of-origin effect is presented with a clear role within the different parts of a brand. The study has a qualitative approach through semi-structured interviews. Three Swedish exporting companies from different lines of business takes part in the study to investigate the purpose. The analysis is structured through three within-case analyses and a cross-case analysis. The study shows that Swedish exporting companies are generally favored by the country-of-origin effect. Although the strength of the Swedish country-of-origin effect differs based on the line of business, market, and product category.