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Predicting and using social tags to improve the accuracy and transparency of recommender systemsGivon, Sharon January 2011 (has links)
This thesis describes work on using content to improve recommendation systems. Personalised recommendations help potential buyers filter information and identify products that they might be interested in. Current recommender systems are based mainly on collaborative filtering (CF) methods, which suffer from two main problems: (1) the ramp-up problem, where items that do not have a sufficient amount of meta-data associated with them cannot be recommended; and (2) lack of transparency due to the fact that recommendations produced by the system are not clearly explained. In this thesis we tackle both of these problems. We outline a framework for generating more accurate recommendations that are based solely on available textual content or in combination with rating information. In particular, we show how content in the form of social tags can help improve recommendations in the book and movie domains. We address the ramp-up problem and show how in cases where they do not exist, social tags can be automatically predicted from available textual content, such as the full texts of books. We evaluate our methods using two sets of data that differ in product type and size. Finally we show how once products are selected to be recommended, social tags can be used to explain the recommendations. We conduct a web-based study to evaluate different styles of explanations and demonstrate how tag-based explanations outperform a common CF-based explanation and how a textual review-like explanation yields the best results in helping users predict how much they will like the recommended items.
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Identification and characterization of a novel human liver-specific organic anion transporter (SLC22A7).January 2000 (has links)
Siu Shu Shun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 100-106). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Contents --- p.ii / Abstract / 摘要 --- p.iv / Abbreviations --- p.vi / List of figures --- p.vii / List of tables --- p.x / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- "Human EST sequencing project, the role and goal" --- p.1 / Chapter 1.2 --- Human liver cDNA sequencing --- p.2 / Chapter 1.3 --- The role of membrane-associated proteins in hepatocellular functions --- p.3 / Chapter 1.3.1 --- Outline of the liver function --- p.3 / Chapter 1.3.2 --- Basic structure of hepatocyte --- p.4 / Chapter 1.3.3 --- Category of membrane associated proteins --- p.5 / Chapter 1.4 --- Identification of human OAT2 gene --- p.7 / Chapter 1.5 --- The multispecific transporter family --- p.8 / Chapter 1.5.1 --- Classification --- p.8 / Chapter 1.5.2 --- The human OAT family --- p.9 / Chapter 1.6 --- The characteristics of rat multispecific OAT2 --- p.11 / Chapter 1.7 --- Clinical significance of organic anion transport proteins --- p.14 / Chapter Chapter 2: --- Materials and Methods / Chapter 2.1 --- Human liver EST sequencing project --- p.16 / Chapter 2.1.1 --- Plating out the adult human liver phage library --- p.16 / Chapter 2.1.2 --- PCR detection and amplification of the cDNA clone --- p.17 / Chapter 2.1.3 --- Automatic cDNA sequencing --- p.18 / Chapter 2.2 --- Cloning of hOAT2 gene into TA cloning vector pT-Adv --- p.19 / Chapter 2.2.1 --- Amplification of hOAT2 by PCR --- p.19 / Chapter 2.2.2 --- Ligation reaction --- p.19 / Chapter 2.2.3 --- Transformation of recombinant plasmid into competent cells --- p.20 / Chapter 2.3 --- Sequence analysis and structural prediction --- p.20 / Chapter 2.4 --- Cloning of the hOAT2 gene into the pQE30 expression vector --- p.21 / Chapter 2.4.1 --- PCR amplification and restriction endonuclease cutting --- p.21 / Chapter 2.4.2 --- Gene clean --- p.22 / Chapter 2.4.3 --- Preparation of bacterial competent cells --- p.23 / Chapter 2.5 --- Small scale synthesis of plasmid DNA --- p.24 / Chapter 2.6 --- Large scale synthesis of plasmid DNA --- p.25 / Chapter 2.7 --- Cloning of the hOAT2 gene into the pSecTag2B mammalian expression vector --- p.26 / Chapter 2.8 --- Cloning of the hOAT2 gene into the pEGFP-C2 fluorescent vector --- p.27 / Chapter 2.8.1 --- Tissue culture and transfection --- p.27 / Chapter 2.8.2 --- Fluorescence microscopy examination --- p.28 / Chapter 2.9 --- Chromosomal mapping of the hOAT2 gene --- p.29 / Chapter 2.9.1 --- Somatic cell hybrids mapping --- p.29 / Chapter 2.9.2 --- Radiation hybrids mapping --- p.29 / Chapter 2.10 --- Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) --- p.30 / Chapter 2.11 --- Western hybridization --- p.32 / Chapter 2.11.1 --- Preparation of anti-hOAT2 antibodies --- p.32 / Chapter 2.11.1.1 --- Synthetic peptide conjugation --- p.32 / Chapter 2.11.1.2 --- Immunizing rabbit polyclonal antibodies for human OAT2 --- p.32 / Chapter 2.11.1.3 --- Purification of the rabbit polyclonal IgG antibodies --- p.33 / Chapter 2.11.2 --- Western blot analysis --- p.33 / Chapter 2.11.2.1 --- Protein isolation from rat liver --- p.33 / Chapter 2.11.2.2 --- Prote in preparation from cell lysate --- p.34 / Chapter 2.11.2.3 --- Quantitation of total proteins by Bradford protein assay --- p.35 / Chapter 2.11.2.4 --- Blotting and hybridization --- p.35 / Chapter Chapter 3: --- Results / Chapter 3.1 --- Catalogue of the 500 liver ESTs --- p.37 / Chapter 3.2 --- Nomenclature of human NLT gene --- p.47 / Chapter 3.3 --- Cloning and characterization of the hOAT2 sequence --- p.48 / Chapter 3.3.1 --- Isolation of hOAT2 cDNA from human liver cDNA library --- p.48 / Chapter 3.3.2 --- The primary and secondary structural analysis of hOAT2 --- p.53 / Chapter 3.3.3 --- Motif search and prediction --- p.61 / Chapter 3.3.4 --- Homology alignment --- p.64 / Chapter 3.4 --- Chromosomal mapping of hOAT2 gene --- p.67 / Chapter 3.4.1 --- Somatic cell hybrid mapping of hOA T2 gene --- p.67 / Chapter 3.4.2 --- Radiation hybrid mapping of hOA T2 gene --- p.69 / Chapter 3.4.3 --- Identification of partial human genomic sequence --- p.73 / Chapter 3.5 --- Detection of the hOAT2 gene expression in human tissues by RT- PCR assay --- p.76 / Chapter 3.6 --- Detection of subcellular localization of hOAT2 protein by conjugating fluorescence protein --- p.81 / Chapter 3.7 --- Immunodetection of protein extracts from cultured cells --- p.83 / Chapter Chapter 4: --- Discussion / Chapter 4.1 --- Characterization of the hepatocellular ESTs --- p.85 / Chapter 4.1.1 --- Classification and frequency distribution of the 500 ESTs --- p.85 / Chapter 4.1.2 --- The expression pattern of membrane associated proteins --- p.87 / Chapter 4.2 --- Tissue distribution and expression profiles of hOAT2 --- p.88 / Chapter 4.3 --- HOAT2 in fetal development --- p.89 / Chapter 4.4 --- Predicting the topology of membrane proteins --- p.90 / Chapter 4.5 --- Chromosomal mapping of human OAT2 --- p.91 / Chapter 4.6 --- Possible functions of hOAT2 --- p.93 / Chapter 4.6.1 --- Hepato-renal relation --- p.93 / Chapter 4.6.2 --- Substrate diversity --- p.95 / Chapter 4.7 --- Fluorescence detection for subcellular localization --- p.96 / Chapter 4.8 --- Conclusion --- p.97 / Chapter 4.9 --- Further aspects --- p.99 / References --- p.100 / Appendix --- p.107
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Gesture Based Navigation and Localization of a Smart Wheelchair using Fiducial MarkersPatel, Jayam Umesh 28 April 2016 (has links)
With the rise in aging population, about 6.8 million American residents are depen- dent on mobility devices for their day to day activity. More than 40% of these users have di?culty in moving the mobility device on their own. These numbers serve as a motivation on developing a system than can help in manipulation with simple muscle activity and localize the mobility device in the user's home in case of medical emergencies. This research is aimed at creating a user interface of Elec- tromyographic Sensor, attached to the forearm, incorporated with present smart wheelchairs and a simple localization technique using ducial markers. The main outcome of the research is a simulator of the smart wheelchair to analyze the results of my research.
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Meta Tag Usage and Credibility Factors in Alternative Medicine WebsitesAndre S. Burton 19 April 2004 (has links)
Clearly, the wide range of health information sources on the World Wide Web has the potential to lead to distribution of inaccurate medical information from unqualified sources bringing a great risk. Given the growing number of Internet users that access health-related information, the need for a more standard means to validate web site content is apparent. This paper examines how source, information, timeliness, accessibility, and design factors impact web document credibility on a narrower health topic - Alternative Medicine. It also examines the contrasts of different levels of credibility with metadata usage as well as the relationships between metadata usage measures. These preliminary results and examinations give an overview of how metadata is currently being used in this subject area.
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Construction and analysis of high reproductive porcine oocyte cDNA librarySu, Yu-liang 27 July 2004 (has links)
The progress of studies on genes concerning the development and differentiation of early swine embryos have been delayed by limited paucity material. In order to identify the porcine ESTs associates with promoting its breeding efficiency, a cDNA library and ESTs database from oocytes of high reproductive swine is established. Oocytes were obtained from Duroc pig by superovulation which was performed by Taiwan Livestock Research Institute, Council of Agriculture. Total RNA was isolated from 50 mature oocytes, reverse transcription is then performed, followed by PCR based amplification of the cDNA. The amplified cDNA size ranges from 0.4 to 5 kb. The derived cDNA were ligated to a pCR2.1 vector, and the library has complexities of about 5.26¡Ñ104 independent clones. A total of 320 clones was picked and sequenced. By BLASTx analysis, among the 123 sequences, more than 43.07%¡]53/123¡^ mitochondrial proteins are found, 56.91¢H¡]70/123¡^ of the sequence were homologous to known transcripts from human, mouse, Drosophila. In nucleotide level analysis, 82.11¢H¡]101/123¡^ matched with the mitochondrial, ribosome genes and 17.89¢H¡]22/123¡^matched with other homologous genes by BLASTn. PCR analysis of the oocyte library for specific genes revealed transcripts for genes including homologous genes¡]2 pairs highly abundance and 2 pairs low abundance genes¡^, housekeeping genes¡]ACT£] and G3PDH¡^ and developmental genes¡]NEK2 and ZP1¡^. However, novel genes of swine are supposed to be the candidates for high productive phenotypes of swine. The library is a valuable resource for the isolation of clones representing genes active at the early stage. The ability to construct cDNA expression library from a few cells will allow gene expression analysis from oocyte biopsies and derived by nuclear transfer procedures.
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Identification of genes encoding secreted proteins of schistosomesShah, Bindiya January 2000 (has links)
No description available.
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SmartBadge : an electronic conference badge using RF and IR communications : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering in Electrical and Computer Engineering from the University of Canterbury, Christchurch, New Zealand /White, Mark Alexander. January 1900 (has links)
Thesis (M.E.)--University of Canterbury, 2006. / Typescript (photocopy). "February 2006." Includes bibliographical references (p. 121-124). Also available via the World Wide Web.
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The Impact of Working Memory, Tags, and Tag Clouds, on Search of WebsitesJanuary 2011 (has links)
abstract: Although there are many forms of organization on the Web, one of the most prominent ways to organize web content and websites are tags. Tags are keywords or terms that are assigned to a specific piece of content in order to help users understand the common relationships between pieces of content. Tags can either be assigned by an algorithm, the author, or the community. These tags can also be organized into tag clouds, which are visual representations of the structure and organization contained implicitly within these tags. Importantly, little is known on how we use these different tagging structures to understand the content and structure of a given site. This project examines 2 different characteristics of tagging structures: font size and spatial orientation. In order to examine how these different characteristics might interact with individual differences in attentional control, a measure of working memory capacity (WMC) was included. The results showed that spatial relationships affect how well users understand the structure of a website. WMC was not shown to have any significant effect; neither was varying the font size. These results should better inform how tags and tag clouds are used on the Web, and also provide an estimation of what properties to include when designing and implementing a tag cloud on a website. / Dissertation/Thesis / M.S. Applied Psychology 2011
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Efecto de la Adición de Extremos Polipeptídicos Hidrofóbicos en la Expresión y Purificación por HIC de cutinasasRobinson Robinson, María del Carmen January 2008 (has links)
El presente trabajo tuvo como objetivo estudiar el efecto de la adición de un extremo
polipeptídico hidrofóbico a una enzima, en particular una cutinasa, en la producción,
recuperación y purificación por Cromatografía de Interacción Hidrofóbica (HIC).
Para realizar este estudio, se escogieron 3 combinaciones de los aminoácidos tirosina (Y),
triptófano (W) y prolina (P), y se realizaron mutaciones en la enzima, mediante la técnica de
“Polymerase Chain Reaction” (PCR). Se obtuvieron satisfactoriamente las mutantes CutinasaWPWP
y Cutinasa-YYY, y en el caso de la combinación YPYPYP se obtuvo una secuencia más
larga en 32 aminoácidos que la diseñada, denominada YPY*.
Como resultado se obtuvo que dichos extremos aumentaron la hidrofobicidad superficial
global teórica de la proteína en un 12,4% en el caso de la Cutinasa-YYY, en un 16,6% en el caso
de la Cutinasa-WPWP y en el caso de una correcta construcción de la Cutinasa-YPYPYP, se
hubiera incrementado en un 14,1%. En el caso de la Cutinasa-YPY* se estima que la
hidrofobicidad superficial teórica es mayor a este último valor, aunque no pudo ser calculado,
debido a que no fue posible aplicar los supuestos que permitían determinarla.
Las cepas recombinantes de E. coli que expresan estas proteínas se crecieron e indujeron
bajo condiciones definidas, y se les extrajo desde la región periplasmática de la célula,
obteniéndose una gran variabilidad (> 50 % en algunos casos) en los resultados en cuanto a
actividad y proteína total presentes en las muestras.
En el caso de la cutinasa mutada con la secuencia YYY se observó una disminución
drástica de la concentración de proteína, en comparación con la cepa nativa, al igual que escasa
actividad cutinasa. Esto tendría relación con la ausencia de prolina en el extremo adicionado, ya
que este aminoácido, más que otorgar hidrofobicidad a la secuencia, le otorgaría estabilidad,
debido a que permite la total exposición del extremo al medio y evita que interactúe con otras
regiones de la proteína. Se descartó esta mutante durante el proceso de purificación, debido a la
casi nula recuperación de proteína.
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MANIPULATING OIL SEED BIOCHEMISTRY TO ENHANCE THE PRODUCTION OF ACETYL-TAGSKornacki, Catherine January 1900 (has links)
Master of Science / Biochemistry and Molecular Biophysics Interdepartmental Program / Timothy P. Durrett / Using vegetable oils directly as an alternative biofuel presents several problems as such oils typically possess poor fuel qualities including high viscosity, low volatility, and poor cold temperature properties. The ornamental shrub Euonymus alatus produces unusual acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) that have an acetyl group in the sn-3 position instead of a long chain fatty acid. The presence of this sn-3 acetyl-group give acetyl-TAGs properties desirable for biofuels, such as reduced viscosity, comparted to the normal long chain triacyglycerols found in most vegetable oils. Acetyl-TAGs are synthesized by the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) and Euonymus fortunei diacylglycerol acetyltransferase (EfDAcT) enzymes. Both enzymes catalyze the transfer of an acetyl group from acetyl-CoA to diaclglycerol (DAG) to produce acetyl-TAGs. Previous work demonstrated that expression of EaDAcT combined with the suppression of a diacylglycerol aceyltransferase (DGAT1) in Camelina sativa led to seeds with 85 mol % acetyl-TAGs. Increasing acetyl-TAG levels further was explored using two strategies. Over expression of citrate lyase to increase the pool of acetyl-CoA to be used as a substrate for the acetyltransferase enzymes failed to increased levels of acetyl-TAGs. A second approach involved expressing EfDAcT in Camelina sativa. EfDAcT has demonstrated higher activity in vitro and in vivo and its expression in yeast leads to approximately 50 % higher levels of acetyl-TAGs compared to EaDAcT. The expression of EfDAcT coupled with the suppression of DGAT1 in Camelina sativa resulted in 90 mol % acetyl-TAGs in the transgenic seeds. Levels of EfDAcT protein analyzed in developing transgenic Camelina sativa seeds across a 40 day time period were highest at 15 and 20 days after flowering. Following these time points acetyl-TAG
accumulation increased rapidly, coinciding with the higher enzyme expression levels. The optimization of additional promoters to ensure expression of EfDAcT in the last half of seed development could represent another way to further increase acetyl-TAGs in the future.
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