141 research outputs found
Cellulase Immobilized Mesoporous Silica Nanocatalysts for Efficient Cellulose-to-Glucose Conversion.
No full textCost-effective data structural preparation
Get PDFPeople structure and represent their data in many different ways. One factor to consider in choosing between different representations is how the structure will affect the effectiveness of algorithms that run over the data. In fact, before sophisticated analytics can be performed, one must usually go through a data preparation phase, where the structural representation of the data is changed to be more suitable for the particular analytics procedure that will be performed. This is necessary because individual analytics algorithms are effective only for certain kinds of structural representations of their input data. Unfortunately, analytics algorithms do not come with a clear description of their desired representation. Hence, time and expertise is required to identify and materialize a suitable representation for each analytics task. In this dissertation, we address this issue in data preparation. Our first contribution focuses on the concept of design independence, in which the intent is to create an analytics algorithm that is effective regardless of the choices of data representations. The benefit of becoming more design independent is that it will reduce or, in the most favorable outcome, remove the cost of manually finding and preparing the most effective structure or schema for the data. In this part of our work, we consider common variations of data source structure that preserve its content. For the analytics task of similarity search, we propose an algorithm that satisfies the design independence property against the studied variations. We then generalize our findings for other structural variations, and prove that it is design independent with respect to these structural variants. We show that humans find its answers at least as desirable as those provided by existing similarity search algorithms. In the case where design independence is not achievable, we address the data preparation issue by proposing an algorithm that finds a cost-effective structure to be imposed on an unstructured dataset. Under this approach, structural information is added to the data source to improve the effectiveness of an algorithm running over the data. We leverage the information from an existing domain of concepts or an ontology to add structure to the data collection in the form of annotations. Because each concept may require different amounts of resources and time in annotating and/or maintaining the data source, we would like to find a set of affordable concepts that improves the effectiveness of an algorithm the most. This is called the cost-effective conceptual design problem. Previous works on this topic assumed that a domain of concepts is simply an unorganized set of concepts. However, real-world domains are often organized, in the form of taxonomies for example. Hence, in this dissertation, we explore a new version of the cost-effective conceptual design problem, using taxonomies of concepts and considering multi-concept queries.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2020-12-01The student, Yodsawalai Chodpathumwan, accepted the attached license on 2018-11-29 at 01:55.The student, Yodsawalai Chodpathumwan, submitted this Dissertation for approval on 2018-11-29 at 02:09.This Dissertation was approved for publication on 2018-12-02 at 10:37.DSpace SAF Submission Ingestion Package generated from Vireo submission #13141 on 2019-02-07 at 14:18:33Made available in DSpace on 2019-02-07T20:36:03Z (GMT). No. of bitstreams: 2
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Previous issue date: 2018-12-02Embargo set by: Seth Robbins for item 109839
Lift date: 2021-02-07T20:36:09Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 109839
Lift date: 2021-02-07T20:39:46Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 109839
Lift date: 2021-02-07T20:44:35Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 109839 on 2021-02-08T10:15:18Z
Cellulase immobilized mesoporous silica nanocatalysts for efficient cellulose-to-glucose conversion
No full textVoces (Re)unidas: Poesía y Narración en Füchse von Llafenko, de Gloria Dünkler
Get PDFEn el presente artículo, indago en dos aspectos del poemario Füchse von Llafenko (2009), de Gloria Dünkler (Pucón, Chile, 1977): la dimensión narrativa de la obra, por un lado, y, por otro, su dimensión política. Respecto del primero, la enunciación lírica se inclina hacia una voz narrativa que cuenta lo que le han contado. A su vez, veintitrés de los cuarenta textos que su autora presenta como poemas pueden ser leídos como micorrrelatos por la presencia de la narración, la brevedad, la fragmentariedad, los personajes apenas esbozados, entre otras características. Respecto del segundo aspecto, los relatos e historias de los colonos de Llakenko no se despliegan en términos de representatividad, sino de intercambio en un espacio compartido. Más que voces narradas, coexisten voces necesarias para quien habla. Tal instancia de narración e intercambio, sin la cual el poema no sería lo que es, desestabiliza la autonomía y autoridad del sujeto poético.The following paper researches two aspects of the poetry book Füchse von Llafenko (2009) written by Gloria Dünkler (Pucón, Chile, 1977). On one hand, I look into the narrative dimension of this book; on the other, I explore the political dimension on it. As regards the first dimension, the lyrical enunciation tends towards a narrative voice that retells what it has been told. Furthemore, twenty three from the forty texts that the author presents as poems can be read as microfiction, because of the presence of narration, their brevity, their fragmentary nature, the slightly sketched characters, among other characteristics. As regards the second dimension, the tales and stories of Llafenko’s settlers do not unfold in terms of representativity, but in terms of exchange in a shared space. More than narrated voices, there are coexisting voices that the speaker finds necessary. Whithout this instance of narrative and exchange, that detabilizes the autonomy and authority of the poetic subject, the poem would not be what it is.Fil: Mellado, Silvia Renee. Universidad Nacional del Comahue. Facultad de Humanidades. Centro Patagónico de Estudios Latinoamericanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Confluencia; Argentin
Regulation of the self-renewal vs. differentiation decision in the C.elegans germline
Get PDFAdult stem cells are the basis of our reproductive potential, of tissue growth and maintenance, and of wound healing and regeneration. Ageing phenotypes such as hair loss or brittle bones in fact reflect the gradual decline of the proliferative capacities of adult stem cells with time. On the other hand, stem cells that proliferate too fast to provoque diseases such as cancer. Understanding the molecular players regulating the decision of stem cells to divide or differentiate is therefore of prime importance to treat conditions caused by stem cell dysfunction. Many pathways that regulate the maintenance and differentiation of stem cells, as well as features distinguishing stem cells from their more committed progeny, are known today, among them the conserved Notch signaling pathway. How these molecules instruct stem cell identity is however largely unknown.
C.elegans germline stem cells, which are maintained by Notch signaling, constitute an excellent model to study the regulation of stem cell identity. C.elegans is amenable to genetic manipulation, to gene knockdown by RNAi, and to transgenesis. Additionally, the C.elegans germline can be readily monitored in live animals through the transparent cuticle as well as dissected for gene expression studies or immunofluorescence.
Here, we use these tools to identify genes that respond to Notch signaling in germline stem cells. We find that many Notch responsive genes reside on the X chromosome. In the following, we uncover a crosstalk between Notch signaling and the C.elegans Polycomb proteins MES-2,-3,-4, and -6, which are known to repress X linked genes in the germline.
Additionally, we identify a role of the CIP/KIP cell cycle inhibitor CKI-2 in the self-renewal versus differentiation decision of C.elegans germline stem cells. We find that CKI-2 is a key target of two conserved stem cell regulators, the RNA binding proteins FBF/Pumilio and MEX-3. Particularly FBF/Pumilio proteins have been implied in stem cell regulation in many organisms, and in C.elegans are required to maintain stem cells during adulthood. Key targets among the mRNAs targeted by FBF/Pumilio proteins have however remained elusive. We demonstrate that both MEX-3 and FBF/Pumilio proteins associate with the cki-2 3’UTR, that FBF/Pumilio binding elements are required for 3’UTR mediated regulation in vivo, and that regulation of CKI-2 by FBF/Pumilio contributes to the maintenance of germline stem cells
Event-level Associations among THC, CBD, Social Context, and Subjective Effects during Cannabis Use Episodes
No full textThis study aimed to examine the subjective effects as a function of THC and CBD doses and social context during cannabis use episodes
Fundraising Behaviors of Listed Companies in Vietnam: An Estimation of the Influence of Government Ownership
Get PDFThis study investigates the capital structure and investment activities of listed companies on the Hanoi Securities Exchange and the Ho Chi Minh Securities Exchange in Vietnam. Estimation analysis using panel data covering the four-year period 2006-2009 revealed the following results. (1) Standard corporate financing theories such as trade-off theory and agency cost theory could be appropriate for explaining the capital structure of listed companies in Vietnam. (2) Compared to the fundraising activities of the companies analyzed by Nguyen (2006) and Biger et al. (2008), the fundraising activities of the listed companies were better explained by standard agency cost theory. (3) There are differences between the determinants of long-term fundraising and short-term fundraising of listed companies in Vietnam. (4) The fundraising determinants of state-controlled companies are different from those of other companies; state-controlled companies have an advantage in tapping external debt funds, and their incentive to reduce their tax payments by debt financing is weaker. (5) The companies listed on the Ho Chi Minh Securities Exchange depended less on debt financing than those listed on the Hanoi Securities Exchange. (6) Listed companies in Vietnam face weak incentives to reduce their tax payments by debt financing because the effective corporate tax rate is low. These results imply that the economic reforms (“Doi Moi”) implemented by the Vietnamese government, which aims to create an economic system based on market mechanisms, have achieved some of their goals in terms of fund mobilization and corporate financing. However, our estimation study illustrates several limitations of economic reforms, such as the opaque relationship between state-controlled companies and government banks, financial restrictions on investment activities, and inactive investment of companies that are state-controlled or listed on the Ho Chi Minh Securities Exchange.Corporate Finance, Capital Structure, Transition Economy, Vietnam
Expression and function of osteopontin variants in HCV-related liver disease and hepatocellular carcinoma.
Get PDFOsteopontin (OPN) is a highly secreted multi-functional sialoprotein that is widely expressed in tissues, blood and urine. It is involved in a number of normal physiological functions, but is also significantly elevated in a number of cancers. While OPN is significantly expressed in hepatocellular carcinoma (HCC) little is known as to its role and if it is expressed in the pre-cancerous hepatitis C virus (HCV) infected liver. In this thesis we show that OPN is expressed in the liver and in HCC as three variants, the full-length protein OPN-A and two splice variants OPN-B and OPN-C. Through production of stable Huh-7 cells expressing the OPN variants, we show for the first time that all variants increase proliferation of a range of cultured hepatoma cell lines in a paracrine manner through
interactions with the cell surface OPN receptor CD44. Similarly, OPN-A (and to a lesser extent OPN-B and –C) accelerated Huh-7 derived tumor growth in a nude mouse model. We also show for the first time expression of all three OPN variants in the non-diseased liver as it was previously thought that splicing was a feature specific for tumor cells. Clinically, OPN is known to be highly expressed in HCC, however, its expression in chronic hepatitis C is not well documented. In this thesis we show that OPN mRNA expression is elevated in the HCV-infected liver with a trend towards increased expression as liver disease progresses. Consistent with an increase in mRNA, serum OPN levels were also increased in the HCV-infected liver although we could find no correlation with degree of liver disease. However, our sample size was small and this section of the thesis needs repeating with a larger HCV-infected patient cohort. Furthermore, we show that elevated OPN expression is not specific to the HCV-infected liver as OPN is also elevated in the HBV-infected and alcoholic liver suggesting that HCV does not drive OPN expression but is more likely as a result of the inflammatory process in the viral infected liver. Interestingly we also show that there is a shift of OPN expression from bile duct epithelial cells in the non-diseased liver to the hepatocyte in the HCV-infected liver which raises the question as to the role of OPN in hepatocyte transformation to facilitate the development of HCC. Our evaluation of serum OPN expression also suggests that OPN has potential as both a diagnostic and potentially prognostic biomarker for not only HCC (arising from HBV and HCV infections and alcohol abuse) but also the earlier stages of HCV-related liver disease. This work for the first time characterises the expression of all OPN variants in the liver including HCC and may be useful for identifying targeted OPN-based therapeutic approaches for HCC and other cancers. Furthermore it also suggests that monitoring OPN in chronic hepatitis C may be
useful in monitoring liver disease progression and early detection of HCC.Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 201
Construction and composition of the squid pen from Doryteuthis pealeii
Get PDFAuthor Posting. © University of Chicago Press, 2019. This article is posted here by permission of University of Chicago Press for personal use, not for redistribution. The definitive version was published in Messerli, M. A., Raihan, M. J., Kobylkevich, B. M., Benson, A. C., Bruening, K. S., Shribak, M., Rosenthal, J. J. C., & Sohn, J. J. Construction and composition of the squid pen from Doryteuthis pealeii. Biological Bulletin. 237(1), (2019): 1-15, doi:10.1086/704209.The pen, or gladius, of the squid is an internalized shell. It serves as a site of attachment for important muscle groups and as a protective barrier for the visceral organs. The pen’s durability and flexibility are derived from its unique composition of chitin and protein. We report the characterization of the structure, development, and composition of pens from Doryteuthis pealeii. The nanofibrils of the polysaccharide β-chitin are arranged in an aligned configuration in only specific regions of the pen. Chitin is secreted early in development, enabling us to characterize the changes in pen morphology prior to hatching. The chitin and proteins are assembled in the shell sac surrounded by fluid that has a significantly different ionic composition from squid plasma. Two groups of proteins are associated with the pen: those on its surface and those embedded within the pen. Only 20 proteins are identified as embedded within the pen. Embedded proteins are classified into six groups, including chitin associated, protease, protease inhibitors, intracellular, extracellular matrix, and those that are unknown. The pen proteins share many conserved domains with proteins from other chitinous structures. We conclude that the pen is one of the least complex, load-bearing, chitin-rich structures currently known and is amenable to further studies to elucidate natural construction mechanisms using chitin and protein.We thank John Dowling for financial support. We thank Kasia Hammar and Louie Kerr of the Marine Biological Laboratory Central Microscopy Facility for help obtaining scanning electron micrographs. We thank Bogdan Budnik and Renee Robinson from the Mass Spectrometry and Proteomics Resource Laboratory for their help and advice with protein identification. We thank Shin-Yi Marzano and Chenchen Feng of South Dakota State University for help with rapid amplification of cDNA ends. Funding for this work was provided by the Eugene and Millicent Bell Fellowship Fund in Tissue Engineering (MAM), an Agriculture and Biological Sciences Undergraduate Research Award (KSB), National Institutes of Health grant R01 GM101701 (MS), National Science Foundation grant IOS1557748 (JJCR), and Israel-United States Binational Science Foundation 2013094 (JJCR).
Literature Cited2020-07-0
Distinct impact of CURLY LEAF and SWINGER on the Arabidopsis Histone H3 Lysine 27 trimethylation pattern is linked to the underlying genetic code
No full textPolycomb Group Proteins (PcG) are a conserved class of transcriptional repressors
in animals and plants, controlling the expression of hundreds of genes. Specifically,
they repress gene expression by histone H3 trimethylation at lysine 27 (H3K27me3)
via the Polycomb Repressive Complex 2 (PRC2). In Arabidopsis thaliana CURLY LEAF
(CLF), a PRC2 methyltransferase, is partially redundant with the closely related protein
SWINGER (SWN). The phenotype of clf null mutant plants is less severe than the
phenotype of clf/swn double mutants. Plants that are mutated in swn exhibit no obvious
phenotype. The large degree of sequence conservation of both CLF and SWN
throughout the plant kingdom, suggests that they have distinct and conserved functions
in plant development.
I set out to identify the individual target genes of CLF and SWN and to uncover their
functions. To this end, I used chromatin immunoprecipitation followed by deep sequencing
to create genome-wide H3K27me3 profiles of wild type, clf and swn seedlings.
The three genotypes share many H3K27me3 target regions but they exhibit partially
distinct methylation profiles. In clf null mutants, H3K27me3 is significantly reduced at
643 genes, indicating that at these genes CLF is the major catalytic component of PRC2.
A part of the CLF dependent genes is significantly physically clustered along chromosomes
and surprisingly, 60% of CLF dependent genes contain a conserved AAACCCTA
or telo box which has been previously reported to enhance transcription. Unexpectedly,
reduction of H3K27me3 in clf mutant plants does not correlate frequently
with an increase of gene expression. The swn mutation can either have the same effect,
oppose or contribute to the effect of clf on the expression of these genes. Moreover, in
swn null mutants, H3K27me3 seems to be slightly increased in 294 genes compared to
wild-type. These results suggest that the interplay between CLF and SWN might be
important to establish wild-type-like H3K27me3 and expression levels. Finally, in swn,
expression of some CLF dependent genes changes dramatically, although H3K27me3
is unaffected. This indicates that SWN might have an H3K27me3 independent function.
In short, these results demonstrate that CLF and SWN have partially distinct effects
on the Arabidopsis thaliana H3K27me3 pattern and that their function is linked to the
underlying genetic code. SWN might control expression in a H3K27me3 independent
pathway and the interplay between CLF and SWN is presumably important to maintain
establish wild-type-like H3K27me3 and expression levels
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