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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Physical Properties of Massive, Star-Forming Galaxies When the Universe Was Only Two Billion Years Old

Fu, Nicole Christina 04 May 2011 (has links)
Due to the finite speed of light and a vast, expanding universe, telescopes are just now receiving the light emitted by galaxies as they were forming in the very early universe. The light from these galaxies has been redshifted (stretched to longer, redder wavelengths) as a result of its journey through expanding space. Using sophisticated techniques and exceptional multi-wavelength optical and infrared data, we isolate a population of 378 galaxies in the process of formation when the Universe was only two billion years old. By matching the distinctive properties of the light spectra of these galaxies to models, the redshift, age, dust content, star formation rate and total stellar mass of each galaxy are determined. Comparing our results to similar surveys of galaxy populations at other redshifts, a picture emerges of the growth and evolution of massive, star-forming galaxies over the course of billions of years.
332

Physical Properties of Massive, Star-Forming Galaxies When the Universe Was Only Two Billion Years Old

Fu, Nicole Christina 04 May 2011 (has links)
Due to the finite speed of light and a vast, expanding universe, telescopes are just now receiving the light emitted by galaxies as they were forming in the very early universe. The light from these galaxies has been redshifted (stretched to longer, redder wavelengths) as a result of its journey through expanding space. Using sophisticated techniques and exceptional multi-wavelength optical and infrared data, we isolate a population of 378 galaxies in the process of formation when the Universe was only two billion years old. By matching the distinctive properties of the light spectra of these galaxies to models, the redshift, age, dust content, star formation rate and total stellar mass of each galaxy are determined. Comparing our results to similar surveys of galaxy populations at other redshifts, a picture emerges of the growth and evolution of massive, star-forming galaxies over the course of billions of years.
333

Physical Properties of Massive, Star-Forming Galaxies When the Universe Was Only Two Billion Years Old

Fu, Nicole Christina 04 May 2011 (has links)
Due to the finite speed of light and a vast, expanding universe, telescopes are just now receiving the light emitted by galaxies as they were forming in the very early universe. The light from these galaxies has been redshifted (stretched to longer, redder wavelengths) as a result of its journey through expanding space. Using sophisticated techniques and exceptional multi-wavelength optical and infrared data, we isolate a population of 378 galaxies in the process of formation when the Universe was only two billion years old. By matching the distinctive properties of the light spectra of these galaxies to models, the redshift, age, dust content, star formation rate and total stellar mass of each galaxy are determined. Comparing our results to similar surveys of galaxy populations at other redshifts, a picture emerges of the growth and evolution of massive, star-forming galaxies over the course of billions of years.
334

Physical Properties of Massive, Star-Forming Galaxies When the Universe Was Only Two Billion Years Old

Fu, Nicole Christina January 2011 (has links)
Due to the finite speed of light and a vast, expanding universe, telescopes are just now receiving the light emitted by galaxies as they were forming in the very early universe. The light from these galaxies has been redshifted (stretched to longer, redder wavelengths) as a result of its journey through expanding space. Using sophisticated techniques and exceptional multi-wavelength optical and infrared data, we isolate a population of 378 galaxies in the process of formation when the Universe was only two billion years old. By matching the distinctive properties of the light spectra of these galaxies to models, the redshift, age, dust content, star formation rate and total stellar mass of each galaxy are determined. Comparing our results to similar surveys of galaxy populations at other redshifts, a picture emerges of the growth and evolution of massive, star-forming galaxies over the course of billions of years.
335

Syntéza π-elektronových systémů vhodných pro přenos a retenci náboje / The synthesis of π-electron systems suitable for transfer and retention of charges

Nejedlý, Jindřich January 2021 (has links)
The aim of my Thesis was to develop a general synthetic methodology for the preparation of long helicenes equipped with suitable functional groups that control their solubility or serve as anchoring groups for attachment to metallic surfaces, especially gold. The well-established transition metal catalyzed [2+2+2] cyclotrimerization of triynes was selected as the key scaffold-forming transformation in the synthesis of long helicenes because of its high regioselectivity, atom efficiency, functional group tolerance and general robustness. A modular approach was used for the preparation of the starting oligoynes, thus enabling a high level of their structural diversity. Individual resorcinol- based aromatic building blocks were interconnected by Sonogashira cross-coupling reactions, providing complex cyclization precursors encompassing up to twelve alkyne units pre-arranged for the multiple [2+2+2] cycloisomerization to produce three six- membered rings from each set of three neighboring alkyne units. Thus, a small series of long helicenes with up to 19 rings constituting the helical scaffold was synthesized. The quadruple cyclization leading to the longest oxahelicene prepared to date was performed in a high-temperature-high-pressure flow reactor at 250 řC in the presence of CpCo(CO)2. The set of...
336

Respektfull design: För ökad förståelse och vilja att förändra : FUCK ME, en utställning om den svåra sjukdomen ME/CFS / Respectful design: For increased understanding and willingness to change : FUCK ME, an exhibition on the severe disease ME/CFS

Sandberg, Emma January 2020 (has links)
In this essay, I go through the different parts that compile my degree project. I have explored the power of graphic design for educational purposes. During my process, I have found a new area of graphic design, respectful design. Something that can be briefly described as design created with the greatest reverence for conveying a difficult subject without diminishing the affected person behind. An approach where one works closely with the involved and frequently checks in, so that nothing is portrayed incorrectly. This along with the constant search for information makes up the basics of respectful design. The disease ME has finally begun to be talked about in society. But the way the disease is portrayed can be argued as incorrect in relation to the bigger picture. As a graphic designer I have analyzed the problem and worked out a possible solution. My conclusion is that strong colors mixed with melancholy and straightforward information can make the subject less heavy and easier to handle. This can open the senses to problem solving and understanding instead of stopping at pity. The aim of the project has been to get away from these dark quilts that the media has placed on us. The goal was to create something that does not hide the awfulness of the disease but informs in a more fun and more inviting way. I strongly believe that graphic design can reduce the social stigma around a topic if done properly. When life is the toughest it has helped me and (after the response of the exhibition) others to learn more about our disease. Above all, if more people know more about the disease, ME- patients will get help. Hopefully society will open it’s arms so that no more people are forced to choose suicide. / I denna uppsats går jag igenom de olika delarna som sammanställer mitt examensprojekt. Jag har i grunden utforskat kraften av grafisk design i utbildningssyfte. Under min process har jag kommit fram till ett nytt område inom grafisk design, respektfull design. Detta går kort att beskriva som design utformat med största vördnad inför att förmedla ett svårt ämne utan att förminska den drabbade människan bakom. Respektfull design innebär att man jobbar nära med inblandade, kollar av hela tiden så att inget porträtteras felaktigt och läser på om ämnet så långt det går. Sjukdomen ME har äntligen börjat talas om i samhället. Men sättet sjukdomen porträtteras kan argumenteras som svartvitt och felaktigt gentemot helhetsbilden. Som grafisk designer har jag analyserat problemet och jobbat fram en möjlig lösning. Min slutsats är att starka färger blandat med melankolisk och rak information kan göra ämnet mindre tungt och mer lätthanterligt. Detta kan öppna sinnena för problemlösning och förståelse istället för att stanna vid medlidande. Syftet med projektet har varit att komma ifrån detta mörk täcke som media lagt över oss. Målet var att skapa något som inte döljer det hemska med sjukdomen men informerar på ett roligare och mer inbjudande sätt. Jag tror stark på att grafisk design kan minska det sociala stigmat runt ett ämne om det görs på rätt sätt. När livet är som tuffast har det hjälpt mig och (efter respons av utställningen) också andra med att utbilda och läsa på. Framför allt om fler vet mer om sjukdomen kommer det att gå att få bättre hjälp. Förhoppningvis öppnar samhället sina armar så att inte fler tvingas till att välja självmord.
337

Cascades of genetic instability resulting from compromised break-induced replication

Vasan, Soumini January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Break-induced replication (BIR) is a mechanism to repair double-strand breaks (DSBs) that possess only a single end that can find homology in the genome. This situation can result from the collapse of replication forks or telomere erosion. BIR frequently produces various genetic instabilities including mutations, loss of heterozygosity, deletions, duplications, and template switching that can result in copy-number variations (CNVs). An important type of genomic rearrangement specifically linked to BIR is half crossovers (HCs), which result from fusions between parts of recombining chromosomes. Because HC formation produces a fused molecule as well as a broken chromosome fragment, these events could be highly destabilizing. Here I demonstrate that HC formation results from the interruption of BIR caused by a defective replisome or premature onset of mitosis. Additionally, I document the existence of half crossover instability cascades (HCC) that resemble cycles of non-reciprocal translocations (NRTs) previously described in human tumors. I postulate that HCs represent a potent source of genetic destabilization with significant consequences that mimic those observed in human diseases, including cancer.
338

Mathematical modeling of cellulase production in an airlift bioreactor / Modélisation mathématique de la production de cellulase dans un réacteur airlift

Bannari, Rachid January 2009 (has links)
Fossil fuel is an important energy source, but is unavoidabiy running out. Since the cellulosic material is the most abundant source of organic matter, the ethanol, which is produced from cellulosic waste materials, is gaining more and more attention. These materials are cheap, renewable and their availability makes them superior compared to other raw materials. The cellulose must be hydrolyzed to glucose before it can be fermented to ethanol. The enzymatic hydrolysis of cellulose using cellulase enzymes is the most widely used method. The production cost of cellulase enzymes is the major cost in ethanol manufacture. To optimize the cost of ethanol production, enzyme stability needs to be improved through maintaining the activity of the enzymes and by optimizing the production of the cellulase. The aim of researchers, engineers and industrials is to get more biomass for the same cost. The filamentous fungus Trichoderma reesei has a long history in the production of the cellulase enzymes. This production can be influenced strongly by varying the growth media and culture conditions (pH, temperature, DO, agitation,... ). At present, it is my opinion that no modelling study has included both the hydrodynamic and kinetic aspects to investigate the effect of shear and mass transfer on the morphology of microorganisms that influence the rheology of the broth and production of cellulase. This thesis presents the development of a mathematical model for cellulase production and the growth of biomass in an airlift bioreactor. The kinetic model is coupled with the methodology of two-phase flow using mathematical models based on the bubble break-up and coalescence to predict mass transfer rate, which is one of the critical factor in the fermentation. A comparison between the results obtained by the developed model and the experimental data is given and discussed. The design proposed for the airlift geometry by Ahamed and Vermette enables us to get a high mass transfer and production rate. The results are very promising with respect to the potential of such a model for industrial use as a prediction tool, and even for design.
339

The clean break principle

Singer, Jill Hilary 01 1900 (has links)
This short dissertation briefly examines the English law statutory provisions and the English judicial approach relating to the clean break principle. A comparison between English law and South African law (in particular s 7 of the Divorce Act 70 of 1979) shows the latter to allow the application of the clean break principle, but rigidity in the legislative wording and further rigidity in the wording by the courts result in the clean break principle not being a dominant feature of South African divorce law. A detailed analysis of South African case law follows in which the fundamental issues relative to the clean break principle are examined, namely the one third rule, universal partnership, misconduct and its effect on court orders, the nature of a contribution and what property is distributed on divorce. Trends in maintenance orders are looked at and how these affect the clean break principle, in particular rehabilitative maintenance and token maintenance wards. / Law / LL.M.
340

Black theology and apartheid theology : an investigation into epitheton theology

Le Roux, Zacharias Petrus 06 1900 (has links)
Black theology and apartheid theology are theologies making use of an epitheton. The use to which the epitheton is put in these theologies is of crucial importance, that is, they are couplet theologies being used in a subjective genitive fashion. The question is whether the couplet becomes a theology of/concerning the epitheton or is it used in an objective genitive fashion. When the epitheton is used in the objective genitive sense it of necessity has to generate an epistemological break in order to distinguish it from orthodox theology. This in turn necessitates a conscientisation of a contextually predicated theology The theology becomes reductive. In this way an epitheton theology forming part of a couplet becomes attenuated and diverges from orthodox theology in the construction of its theology. This can lead to the espousal of heretical teachings. Conclusion: The conclusion arrived at is the objective genitive sense, that an epitheton theology, in for the purpose of advancing a particular secular base or pseudo-theological base for Christian society, once it has gained a life of its own, will lead to heresy unless erroneous or sinful teachings are confessed and repented of. / Philosophy, Practical and Systematic Theology / D. Th. (Systematic Theology)

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