• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 230
  • 165
  • 61
  • 49
  • 40
  • 8
  • 7
  • 7
  • 6
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • Tagged with
  • 679
  • 160
  • 121
  • 89
  • 86
  • 82
  • 75
  • 55
  • 44
  • 41
  • 39
  • 39
  • 37
  • 37
  • 35
  • 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.
31

Dissecting signalling contributions of the alpha and beta subunits of the GM-CSF receptor

Perugini, Michelle January 2007 (has links)
Normal tissue homeostasis and appropriate responses to injury and infection are dependent on cellular communication mediated by cell surface receptors that respond to extrinsic stimuli. The GM-CSF receptor was the major focus of this project. This receptor shares a common signalling subunit, β [subscript c], with the IL-3 and IL-5 receptors. The unique GM-CSF receptor α-subunit ( GMRα ) confers ligand binding specificity to the complex and is essential for GM-CSF receptor signalling, although the full complement of signalling events mediated by GMRα remains elusive. Through cloning of candidate interacting proteins, expression and co-immunoprecipitation studies, we have confirmed interactions for two proteins previously reported to interact with the GMRα, p85 and IKKβ. Additionally, we identified the Src family kinase, Lyn, as a novel direct interacting partner of GMRα and provide insights into possible roles of this kinase in initiating signalling from the GM-CSF receptor. In addition to GMRα associated events we aimed to further characterise the role of the common β [subscript c] subunit in GM-CSF mediated signalling. We utilised two classes of consitutively active β [subscript c] mutants ( extracellular or transmembrane ) which transform the bi-potential myeloid FDB1 cell line to either factor-independent growth and survival, or granulocyte-macrophage differentiation, respectively. Here we report a comprehensive biochemical analysis of signalling by these two classes of mutants in this cell line. The two activated GMR mutants displayed distinct and non-overlapping signalling capacity. In particular, expression of a mutant with a substitution in the transmembrane domain ( V449E ) selectively activated JAK / STAT5 and MAPK pathways resulting in a high level of sensitivity to JAK and MEK inhibitors. In contrast, expression of a mutant with a 37 amino acid duplication in its extracellular domain ( FI Δ ) selectively activates the PI3K / AKT and IKKβ / NFkB pathways. Cells responding to this mutant display a relative high level of sensitivity to two independent PI3K inhibitors and relative resistance to inhibition of MEK and JAK2. The non-overlapping nature of signalling by these two activated mutants suggests that there are alternative modes of receptor activation that differentially dependent on JAK2 and that act synergistically in the mature liganded cytokine receptor complex. Further detailed analysis of these mutants will facilitate the dissection of the signalling pathways involved in the GM-CSF response that mediate proliferation, survival and differentiation. / Thesis (Ph.D.)--School of Medicine, 2007.
32

Ant colony for TSP

Feng, Yinda January 2010 (has links)
The aim of this work is to investigate Ant Colony Algorithm for the traveling salesman problem (TSP). Ants of the artificial colony are able to generate successively shorter feasible tours by using information accumulated in the form of a pheromone trail deposited on the edges of the TSP graph. This paper is based on the ideas of ant colony algorithm and analysis the main parameters of the ant colony algorithm. Experimental results for solving TSP problems with ant colony algorithm show great effectiveness.
33

Multi-input multi-output (MIMO) detection by a colony of ants

Jaber, Dana N. 02 June 2009 (has links)
The traditional mobile radio channel has always suffered from the detrimental effects of multipath fading. The use of multiple antennae at both ends of the wireless channel has proven to be very effective in combatting fading and enhancing the channel's spectral efficiency. To exploit the benefits offered by Multi-Input Multi-Output (MIMO) systems, both the transmitter and the receiver have to be optimally designed. In this thesis, we are concerned with the problem of receiver design for MIMO systems in a spatial multiplexing scheme. The MIMO detection problem is an NP-hard combinatorial optimization problem. Solving this problem to optimality requires an exponential search over the space of all possible transmitted symbols in order to find the closest point in a Euclidean sense to the received symbols; a procedure that is infeasible for large systems. We introduce a new heuristic algorithm for the detection of a MIMO wireless system based on the Ant Colony Optimization (ACO) metaheuristic. The new algorithm, AntMIMO, has a simple architecture and achieves near maximum likelihood performance in polynomial time.
34

Optimizing the Traffic Signal Setting Problem on the Graph Model

Dong, Jian-fu 29 August 2006 (has links)
The traffic signal optimization problem is to find a traffic signal setting in a traffic network such that vehicles could arrive at their destination with minimum waiting time. The design of traffic signal setting to decrease waiting time for vehicles moving on the roads in urban city is important but difficult. In this thesis, we use a graph model to represent a traffic network. We propose two signal setting algorithms, a fast heuristic approach and an evolutionary algorithm based on the ant colony optimization (ACO) method, to give a good traffic signal setting. The results show that we could find better solutions by ACO algorithms, and the heuristic algorithm is faster but gets more total waiting time for vehicles. Furthermore, we transform the traffic network data of Kaohsiung city in Taiwan into our traffic graph model and test our algorithm on this traffic graph.
35

A Study of Japanese Colonial Education Policies in Taiwan ¡V the Case of Language Textbooks for Elementary School.

Chen, Hung-Wen 11 June 2001 (has links)
The major purpose of this study was to explore the relationship between Japanese colonial policies and colonial education, and its impact upon the contents of public elementary school and the language textbooks. Through a variety of analyses, the study intended to discuss the issues relating to the formation and implementation of Japanese colonial educational policies in Taiwan, and to prove the colonial elites to reproduce specific Japanese cultural values, political orientations on the minds of Taiwan¡¦s children in public elementary school. This study, based upon the result of review of related literature and documents and the analyses of the contents of public school¡¦s language textbooks, traced several controversies in the formation and implementation of Japanese colonial educational policies during the occupation period. To deepen the researchers¡¦ understanding of the process, some in-depth interviews of educated people aged over 70 were also conducted. The final conclusions were reached through the combination of these three steps of explorations and some suggestions have been achieved. The conclusions of this study were as follows: ¢¹. The implementation of colonial policies is based on the extent of how the colonial education was practiced. The goals and intentions of colonial elites could also be found in the colonial education policies. ¢º. The colonial education policies changed along with the needs of social situations in Taiwan and in Japanese, and perspectives of the key colonial elites. ¢». The key components which the language textbooks were trying to brain wash Taiwan¡¦s children were teaching Japanese language, moral education, knowledge and skills in life, the spirit of Japanese culture, and the development of healthy bodies in students. ¢¼. The contents of language textbooks changed along with the changes of colonial education policies. The perspectives of colonial elites could also be found in the changing of shifts of emphases in the contents of the language textbooks. ¢½. The formation and implementation of colonial educational policies in Taiwan are based on Japan¡¦s colonial policies, and the control of contents and their ideology in language textbooks were the major approaches. Two suggestions for further study were provided by the researcher as follows¡G ¢¹. Suggestion for related studies Based upon the conclusions of the study, interested researchers can deepen their understanding of the topic by analyzing textbooks of other subjects, extending the study¡¦s span to include elementary schools in 1941-1945, and conducting more oral history interviews. ¢º. Suggestion for comparative studies The conclusions of this study could be the starting points for the researchers to conduct a comparative study the contents of school textbooks in Japan, Taiwan, Manchu and Korea during the colonial period.
36

A Study for Price-Based Unit Commitment with Carbon

Li, Yuan-hui 01 July 2009 (has links)
In this thesis, the Hybrid Genetic Algorithm-Ant Colony Optimization (GACO) approach is presented to solve the unit commitment problem (UC), and comparison with the results obtained using literature methods. Then this thesis applied the ability of the Genetic Algorithm (GA) operated after Ant Colony Optimization (ACO) can promote the ACO efficiency. The objective of GA is to improve the searching quality of ants by optimizing themselves to generate a better result, because the ants produced randomly by pheromone process are not necessary better. This method can not only enhance the neighborhood search, but can also search the optimum solution quickly to advance convergence. The other objective of this thesis is to investigate an influence of emission constraints on generation scheduling. The motivation for this objective comes from the efforts to reduce negative trends in a climate change. In this market structure, the independent power producers have to deal with several complex issues arising from uncertainties in spot market prices, and technical constraints which need to be considered while scheduling generation and trading for the next day. In addition to finding dispatch and unit commitment decisions while maximizing its profit, their scheduling models should include trading decisions like spot-market buy and sell. The model proposed in this thesis build on the combined carbon finance and spot market formulation, and help generators in deciding on when these commitments could be beneficial.
37

Applying ant colony optimization to solve the single machine total tardiness problem

Bauer, Andreas, Bullnheimer, Bernd, Hartl, Richard F., Strauß, Christine January 1999 (has links) (PDF)
Ant Colony Optimization is a relatively new meta-heuristic that has proven its quality and versatility on various combinatorial optimization problems such as the traveling salesman problem, the vehicle routing problem and the job shop scheduling problem. The paper introduces an Ant Colony Optimization approach to solve the problem of determining a job-sequence that minimizes the overall tardiness for a given set of jobs to be processed on a single, continuously available machine, the Single Machine Total Tardiness Problem. We experiment with various heuristic information as well as with variants for local search. Experiments with 250 benchmark problems with 50 and 100 jobs illustrate that Ant Colony Optimization is an adequate method to tackle the SMTTP. (author's abstract) / Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
38

När bina tystnar : Colony Collapse Disorder bakom honungsbiets (Apis mellifera) försvinnande

Persson, Erik January 2014 (has links)
Under vintrarna 2006/2007 och 2007/2008 vittnade man i USA om storskaliga förluster avhonungsbin (Apis mellifera). Gemensamma symptom för dessa förluster var att arbetarbinförsvann från kolonierna fastän det fanns rikligt med mat och inga tecken på infektion av någonparasit. Fenomenet fick namnet Colony Collapse Disorder (CCD) eftersom det slutgiltigastadiet var att kolonierna kollapsade. Denna översiktstudie ämnar till att reda ut begreppetCCD och se över vilka potentiella orsaker den rådande forskningen föreslår och vad man harkommit fram till sedan utbrottet 2006. Resultaten indikerar att det antagligen inte är en ensamfaktor bakom CCD utan att flera faktorer samverkar. Det finns ett antal hot mot bina medsymptom som liknar CCD och som antas bidra till försvinnandet. Ett hot är det parasitiskakvalstret Varroa destructor som förutom att det suger binas hemolymfa även agerar vektor åtflera CCD-förknippade patogener som Nosema ceranae och Israeli acute paralysis virus(IAPV). Dessutom sänker V. destructor binas immunförsvar vilket gör att virus som överförsvia kvalstret replikeras snabbare och blir dödligare. Man har även visat att vanligt förekommandebekämpningsmedel kan göra bina mer mottagliga för sjukdomar. Där hittade man ettsignifikant samband med just N. ceranae vilket är i enlighet med teorin om att flera faktorersamverkar. I nuläget bidrar CCD fortfarande till bidöd men är inte lika akut som 2006/2007.Istället är det andra hot såsom biodlares svårighet att behandla invasion av varroakvalster,kalla vintrar och att bisamhällen svälter ihjäl för att de invintras i för små populationer, som ärett större hot än CCD.
39

Use of granulocyte colony-stimulating factor for treatment of aplastic anemia

Kojima, Seiji 11 1900 (has links)
No description available.
40

The immunoregulatory role of seminal plasma in early murine and human pregnancy /

Tremellen, Kelton Paul. January 1998 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Obstetrics and Gynaecology, 1999. / Errata posted inside back end-paper (leaf 250). Bibliography: leaves 204-249.

Page generated in 0.0298 seconds