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Molecular and Physiological Characterization of the Flowering Time Control Protein, HvFCA and its Role in ABA Signalling and Seed GerminationKumar, Santosh 07 April 2010 (has links)
The RNA binding protein Flowering Time Control Locus A (FCA) regulates
flowering in rice and Arabidopsis. The abscisic acid binding protein ABAP1 shares high sequence homology to FCA and was considered the FCA homologue in barley. The current study investigates the existence of ABAP1 as an independent gene product and also the cloning, characterization and functional significance of the gamma (γ) isoform of FCA from barley.
Barley FCA protein showed higher sequence similarity to wheat and rice
FCA compared to Arabidopsis FCA. It contains two RNA recognition motifs
(RRMs), a glycine rich region at the N-terminal end, the WW domain and a poly-glutamine region immediately downstream of WW domain at the C-terminal. In developing barley embryos, FCA transcripts could be detected from 2 days after pollination (DAP) up to late maturity without any detectable change within these stages. FCA transcript levels declined as germination progressed in barley embryos and the FCA transcripts were retained for longer duration when germination was reduced with application of ABA. FCA also showed up-regulation by ABA and abiotic stresses in barley germinating seeds and seedlings. Transient co-expression of barley FCA or a truncated FCA (lacking RRM) with a maize VP1 promoter-GUS construct or a wheat Em gene promoter-GUS construct in barley aleurone layer protoplasts led to increased GUS activity in both cases. Adding ABA during the incubation enhanced the observed increase due to FCA expression. Similar effects of transient over-expression of FCA in barley embryos affected VP1. Barley FCA localized to the nucleus. This nuclear localization was due to the nuclear localization signal within the protein and not due to the RNA recognition motifs (RRMs) as the truncated FCA lacking RRMs also localized to the nucleus. Barley FCA did not restore the flowering phenotype in an Arabidopsis fca-1 mutant. In conclusion, I have shown that barley FCA is up-regulated by ABA and stress in embryos and affects ABA signalling in barley caryopses. The properties of FCA appear to have diverged between dicot and monocot systems.
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Molecular and Physiological Characterization of the Flowering Time Control Protein, HvFCA and its Role in ABA Signalling and Seed GerminationKumar, Santosh 07 April 2010 (has links)
The RNA binding protein Flowering Time Control Locus A (FCA) regulates
flowering in rice and Arabidopsis. The abscisic acid binding protein ABAP1 shares high sequence homology to FCA and was considered the FCA homologue in barley. The current study investigates the existence of ABAP1 as an independent gene product and also the cloning, characterization and functional significance of the gamma (γ) isoform of FCA from barley.
Barley FCA protein showed higher sequence similarity to wheat and rice
FCA compared to Arabidopsis FCA. It contains two RNA recognition motifs
(RRMs), a glycine rich region at the N-terminal end, the WW domain and a poly-glutamine region immediately downstream of WW domain at the C-terminal. In developing barley embryos, FCA transcripts could be detected from 2 days after pollination (DAP) up to late maturity without any detectable change within these stages. FCA transcript levels declined as germination progressed in barley embryos and the FCA transcripts were retained for longer duration when germination was reduced with application of ABA. FCA also showed up-regulation by ABA and abiotic stresses in barley germinating seeds and seedlings. Transient co-expression of barley FCA or a truncated FCA (lacking RRM) with a maize VP1 promoter-GUS construct or a wheat Em gene promoter-GUS construct in barley aleurone layer protoplasts led to increased GUS activity in both cases. Adding ABA during the incubation enhanced the observed increase due to FCA expression. Similar effects of transient over-expression of FCA in barley embryos affected VP1. Barley FCA localized to the nucleus. This nuclear localization was due to the nuclear localization signal within the protein and not due to the RNA recognition motifs (RRMs) as the truncated FCA lacking RRMs also localized to the nucleus. Barley FCA did not restore the flowering phenotype in an Arabidopsis fca-1 mutant. In conclusion, I have shown that barley FCA is up-regulated by ABA and stress in embryos and affects ABA signalling in barley caryopses. The properties of FCA appear to have diverged between dicot and monocot systems.
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Retail distribution review : a critical evaluation of the retail distribution reviewMcCourt, James January 2017 (has links)
Despite the high profile nature of the interventions made by regulators after the global financial crisis, there have been few objective assessments of their success and of the orthodoxy of market failure analysis that underpins the rationale for taking action. This study addresses both literature gaps by developing a distribution landscape segment model to measure the success of an exemplar; the Retail Distribution Review (RDR). It also undertakes exploratory research to establish a basis for a diagnostic paradigm based on customer value rather than well established, but criticised, classical economic indicators. A “stock flow” based model was constructed to assess post-RDR levels of asymmetry, agency and trust. The absence of source data prompted a second exploratory phase of research into Trust as a welfare benefit, using customer focus groups and telephone surveys. An evidential basis for an alternative framework based on what consumers value, rather than how economists think is rational for them to act, was established. The model results indicated a landscape which is more complex than 2013, with competing interests transmuted rather than eradicated and information asymmetry growing rather than shrinking. The results support a view that interventions focussing on narrow “market” definitions do not reflect the complexity of human behaviour and are simply “squeezing the balloon”. The customer value research found that trust is complicated and related to several key “motivators”. These have underlying attributes which differ between socio economic groups, the financial objectives and whether customers have advisers. The conclusion reached is that an evidence based customer perspective should be at the heart of regulatory analysis, if public welfare is to be maximised. The study provides evidence of complexities and connectedness between actors and economic forces in the retail financial services landscape, cautiously supporting the literature on regulatory interventions as socio-technical assemblages. It argues that the customer value framework enriches the regulatory toolkit by forming a guard against intellectual capture and unintended consequences of shaping reality to fit a so-called perfect market model.
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Toward functional characterization of <i>Triticum aestivum WFCA</i>-coding sequencesHoffman, Travis L. 06 July 2012
<p>Flowering is a critical step in the plant life cycle. If flowering occurs too early or
too late, seed production suffers. Flowering is regulated through numerous flowering
repressors. As long as these repressors persist, the plant will remain in a vegetative
growth stage. Some plants possess two separate genetic pathways, the autonomous
pathway and the vernalization pathway, that promote the transition to flowering through
stable downregulation of flowering repressors. Once the plant achieves floral
competence, it will flower under inductive environmental conditions.</p>
<p>In <i>Arabidopsis</i>, <i>FCA</i> is a key autonomous pathway gene, acting with <i>FY</i> to
promote the floral transition. Recently, gene sequences resembling <i>FCA</i> were cloned
from hexaploid wheat (<i>Triticum aestivum</i>) and designated as <i>WFCA</i>. WFCA shows
numerous similarities to the FCA peptide, especially regarding three key regions: two
RNA Recognition Motifs and the WW domain. This study seeks to determine if <i>WFCA</i>
genes function similar to <i>FCA</i> by determining if they are able to complement the <i>fca-1</i>
mutant of <i>Arabidopsis thaliana</i>.</p>
<p>T1 progeny from an <i>Arabidopsis fca-1</i> plant transformed with <i>WFCA</i> were
grown without vernalization and assayed for the final leaf number (FLN). The late
flowering <i>fca-1</i> control plants bolted with an average FLN of 14.8 while the T1
population had an average FLN of 14.3. Although the numerical difference is slight, the
results are statistically significant, and suggest that <i>WFCA</i> genes may have some degree of flowering promotion activity in <i>Arabidopsis</i>. The lack of strong complementation
may be due to divergence of the <i>WFCA</i> genes from their <i>Arabidopsis</i> counterparts. With
increasing evidence for divergence in flowering promotion between monocot and dicot
species, the development of a robust monocot model system appears to be critical to
provide a good framework to assist studies of the particular nuances of the monocot
flowering process.</p>
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Toward functional characterization of <i>Triticum aestivum WFCA</i>-coding sequencesHoffman, Travis L. 06 July 2012 (has links)
<p>Flowering is a critical step in the plant life cycle. If flowering occurs too early or
too late, seed production suffers. Flowering is regulated through numerous flowering
repressors. As long as these repressors persist, the plant will remain in a vegetative
growth stage. Some plants possess two separate genetic pathways, the autonomous
pathway and the vernalization pathway, that promote the transition to flowering through
stable downregulation of flowering repressors. Once the plant achieves floral
competence, it will flower under inductive environmental conditions.</p>
<p>In <i>Arabidopsis</i>, <i>FCA</i> is a key autonomous pathway gene, acting with <i>FY</i> to
promote the floral transition. Recently, gene sequences resembling <i>FCA</i> were cloned
from hexaploid wheat (<i>Triticum aestivum</i>) and designated as <i>WFCA</i>. WFCA shows
numerous similarities to the FCA peptide, especially regarding three key regions: two
RNA Recognition Motifs and the WW domain. This study seeks to determine if <i>WFCA</i>
genes function similar to <i>FCA</i> by determining if they are able to complement the <i>fca-1</i>
mutant of <i>Arabidopsis thaliana</i>.</p>
<p>T1 progeny from an <i>Arabidopsis fca-1</i> plant transformed with <i>WFCA</i> were
grown without vernalization and assayed for the final leaf number (FLN). The late
flowering <i>fca-1</i> control plants bolted with an average FLN of 14.8 while the T1
population had an average FLN of 14.3. Although the numerical difference is slight, the
results are statistically significant, and suggest that <i>WFCA</i> genes may have some degree of flowering promotion activity in <i>Arabidopsis</i>. The lack of strong complementation
may be due to divergence of the <i>WFCA</i> genes from their <i>Arabidopsis</i> counterparts. With
increasing evidence for divergence in flowering promotion between monocot and dicot
species, the development of a robust monocot model system appears to be critical to
provide a good framework to assist studies of the particular nuances of the monocot
flowering process.</p>
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A SYSTEM FOR AUTOMATED CONTENT ORGANIZATIONTian, Ye 23 June 2006 (has links)
No description available.
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An Experimental Application of Formal Concept Analysis to Research CommunitiesKiraly, Bret D. 10 December 2008 (has links)
No description available.
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Ontology-based approaches to improve RDF Triple StoreAlbahli, Saleh Mohammad 21 March 2016 (has links)
No description available.
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Detecting k-Balanced Trusted Cliques in Signed Social NetworksHao, F., Yau, S.S., Min, Geyong, Yang, L.T. January 2014 (has links)
No / k-Clique detection enables computer scientists and sociologists to analyze social networks' latent structure and thus understand their structural and functional properties. However, the existing k-clique-detection approaches are not applicable to signed social networks directly because of positive and negative links. The authors' approach to detecting k-balanced trusted cliques in such networks bases the detection algorithm on formal context analysis. It constructs formal contexts using the modified adjacency matrix after converting a signed social network into an unweighted one. Experimental results demonstrate that their algorithm can efficiently identify the trusted cliques.
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Protection des contenus des images médicales par camouflage d'informations secrètes pour l'aide à la télémédecine / Medical image content protection by secret information hiding to support telemedicineAl-Shaikh, Mu'ath 22 April 2016 (has links)
La protection de l’image médicale numérique comporte au moins deux aspects principaux: la sécurité et l’authenticité. Afin d’assurer la sécurité, l’information doit être protégée vis-à-vis des utilisateurs non autorisés. L’authenticité permet quant à elle de s’assurer que la donnée reçue n’est pas modifiée, n’est pas altérée, et qu’elle est bien envoyée par l’expéditeur supposé. La « technique » cryptographique garantit la sécurité en faisant l’hypothèse que l’expéditeur et le destinataire ont des clés permettant respectivement de crypter et de décrypter le message. De cette manière, seule la personne possédant la bonne clé peut décrypter le message et accéder au contenu de la donnée médicale. Dans cette thèse, nous avons apporté plusieurs contributions. La principale contribution est la proposition de solutions de tatouage d'images médicales robustes et réversibles dans le domaine spatial basées respectivement sur l’analyse de concepts formels (FCA) et le diagramme de décision binaire par suppression des zéros (ZBDD). La seconde est une approche de tatouage d’image médicale semi-aveugle pour la détection de modifications malveillantes. Une autre contribution est la proposition d'un système de chiffrement symétrique sécurisé basé sur les N-grams. La dernière contribution est un système hybride de tatouage et de cryptographie d’image médicale qui s’appuie sur une nouvelle forme de carte chaotique (chaotic map) pour générer des clés ayant des propriétés spécifiques, et qui permet d'obtenir une meilleure efficacité, une grande robustesse et une faible complexité par rapport aux approches existantes. / The protection of digital medical image comprises at least two main aspects: security and authentication. In order to ensure the security, the information has to be protected from the unauthorized users while the authentication confirms that the received data is not affected or modified and is sent by the intended sender (watermarking). The cryptography technique proves the security issues by assuming the intended sender and intended receiver have some security aspects called keys. So, after encryption of the digital material from the sender side, the person who has the key (receiver) can decrypt and access the content of the digital material. In this thesis, we have brought several contributions. The main one is the provision of robust and reversible medical image watermarking solutions in the spatial domain based respectively on FCA and ZBDD. The second one is a semi-blind medical image watermarking approach for the tamper detection. Another contribution is the proposal of a secure symmetric encryption system based on N-gram. The last contribution is a hybrid watermarking and cryptography medical image system which focuses on a new form of chaotic map to generate keys with specific properties, and achieves better efficiency, high robustness and low complexity than the existing approaches.
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