310 resultados para litterary hybridisation


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Craniofacial anomalies are a common feature of human congenital dysmorphology syndromes, suggesting that genes expressed in the developing face are likely to play a wider role in embryonic development. To facilitate the identification of genes involved in embryogenesis, we previously constructed an enriched cDNA library by subtracting adult mouse liver cDNA from that of embryonic day (E)10.5 mouse pharyngeal arch cDNA. From this library, 273 unique clones were sequenced and known proteins binned into functional categories in order to assess enrichment of the library (1). We have now selected 31 novel and poorly characterised genes from this library and present bioinformatic analysis to predict proteins encoded by these genes, and to detect evolutionary conservation. Of these genes 61% (19/31) showed restricted expression in the developing embryo, and a subset of these was chosen for further in silico characterisation as well as experimental determination of subcellular localisation based on transient transfection of predicted full-length coding sequences into mammalian cell lines. Where a human orthologue of these genes was detected, chromosomal localisation was determined relative to known loci for human congenital disease.

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The growth, maintenance and lysis processes of Nitrobacter were characterised. A Nitrobacter culture was enriched in a sequencing batch reactor (SBR). Fluorescent in situ hybridisation showed that Nitrobacter constituted 73% of the bacterial population. Batch tests were carried out to measure the oxygen uptake rate and/or nitrite consumption rate when both nitrite and CO2 were in excess, and in the absence of either of these two substrates. The results obtained, along with the SBR performance data, allowed the determination of the maintenance coefficient and in situ cell lysis rate of Nitrobacter. Nitrobacter spends a significant amount of energy for maintenance, which varies considerably with the specific growth rate. At maximum growth, Nitrobacter consume nitrite at a rate of 0.042 mgN/mgCOD(biomass)center dot h for maintenance purposes, which increases more than threefold to 0.143 mgN/mgCOD(biomass)center dot h in the absence of growth. In the SBR, where Nitrobacter grew at 40% of its maximum growth rate, a maintenance coefficient of 0.113 mgN/mgCOD center dot h was found, resulting in 42% of the total amount of nitrite being consumed for maintenance. The above three maintenance coefficient values obtained at different growth rates appear to support the maintenance model proposed in Pirt (1982). The in situ lysis rate of Nitrobacter was determined to be 0.07/day under aerobic conditions at 22 C and pH 7.3. Further, the maximum specific growth rate of Nitrobacter was estimated to be 0.02/h (0.48/day). The affinity constant of Nitrobacter with respect to nitrite was determined to be 1.50 mgNO(2)(-)-N/L, independent of the presence or absence of CO2. (c) 2006 Wiley Periodicals, Inc.

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The DNA sequence of the chromosomal gene cluster encoding the SEF14 fimbriae of Salmonella enterica serovar Enteritidis was determined. Five contiguous open reading frames, sefABCDE, were identified. The sefE gene shared significant homology with araC-like positive regulators. Serovar-associated virulence plasmid (SAP) genes orf7,8,9 and pefI were identified immediately adjacent to the sef operon. The pefI gene encoded a putative regulator of the Plasmid-encoded fimbrial antigen (PEF) expression. The entire sef--pef region, flanked by two IS-like elements, was inserted adjacent to leuX that encoded a transfer RNA molecule. The organisation of this region was suggestive of a classic pathogenicity islet. Southern hybridisation confirmed two copies of the SAP derived orf7,8,9 and pefI region in S. Enteritidis, one in the chromosome and one on the SAP. Of other group D Salmonella, only S. Blegdam and S. Moscow harboured both chromosomal and plasmid copies of pefI--orf9 region although polymorphism was evident.

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The genome of Salmonella enterica serovar Enteritidis was shown to possess three IS3-like insertion elements, designated IS1230A, B and C, and each was cloned and their respective deoxynucleotide sequences determined. Mutations in elements IS1230A and B resulted in frameshifts in the open reading frames that encoded a putative transposase to be inactive. IS1230C was truncated at nucleotide 774 relative to IS1230B and therefore did not possess the 3' terminal inverted repeat. The three IS1230 derivatives were closely related to each other based on nucleotide sequence similarity. IS1230A was located adjacent to the sef operon encoding SEF14 fimbriae located at minute 97 of the genome of S. Enteritidis. IS1230B was located adjacent to the umuDC operon at minute 42.5 on the genome, itself located near to one terminus of an 815-kb genome inversion of S. Enteritidis relative to S. Typhimurium. IS1230C was located next to attB, the bacteriophage P22 attachment site, and proB, encoding gamma-glutamyl phosphate reductase. A truncated 3' remnant of IS1230, designated IS1230T, was identified in a clinical isolate of S. Typhimurium DT193 strain 2391. This element was located next to attB adjacent to which were bacteriophage P22-like sequences. Southern hybridisation of total genomic DNA from eighteen phage types of S. Enteritidis and eighteen definitive types of S. Typhimurium showed similar, if not identical, restriction fragment profiles in the respective serovars when probed with IS1230A.

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The nucleotide sequence of a 3 kb region immediately upstream of the sef operon of Salmonella enteritidis was determined. A 1230 base pair insertion sequence which shared sequence identity (> 75%) with members of the IS3 family was revealed. This element, designated IS1230, had almost identical (90% identity) terminal inverted repeats to Escherichia coli IS3 but unlike other IS3-like sequences lacked the two characteristic open reading frames which encode the putative transposase. S. enteritidis possessed only one copy of this insertion sequence although Southern hybridisation analysis of restriction digests of genomic DNA revealed another fragment located in a region different from the sef operon which hybridised weakly which suggested the presence of an IS1230 homologue. The distribution of IS1230 and IS1230-like elements was shown to be widespread amongst salmonellas and the patterns of restriction fragments which hybridised differed significantly between Salmonella serotypes and it is suggested that IS1230 has potential for development as a differential diagnostic tool.

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Over the last twenty years, we have been continuously seeing R&D efforts and activities in developing optical fibre grating devices and technologies and exploring their applications for telecommunications, optical signal processing and smart sensing, and recently for medical care and biophotonics. In addition, we have also witnessed successful commercialisation of these R&Ds, especially in the area of fibre Bragg grating (FBG) based distributed sensor network systems and technologies for engineering structure monitoring in industrial sectors such as oil, energy and civil engineering. Despite countless published reports and papers and commercial realisation, we are still seeing significant and novel research activities in this area. This invited paper will give an overview on recent advances in fibre grating devices and their sensing applications with a focus on novel fibre gratings and their functions and grating structures in speciality fibres. The most recent developments in (i) femtosecond inscription for microfluidic/grating devices, (2) tilted grating based novel polarisation devices and (3) dual-peak long-period grating based DNA hybridisation sensors will be discussed.

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The Scintillation Proximity Assay (SPA) is a method that is frequently used to detect and quantify the strength of intermolecular interactions between a biological receptor and ligand molecule in aqueous media. This thesis describes the synthesis of scintillant-tagged-compounds for application in a novel cell-based SPA. A series of 4-functianlised-2,5-diphenyloxazole molecules were synthesised. These 4-functionalised-2,5-diphenyloxazoles were evaluated by Sense Proteomic Ltd. Accordingly, the molecules were evaluated for the ability to scintillate in the presence of ionising radiation. In addition, the molecules were incorporated into liposomal preparations which were subsequently evaluated for the ability to scintillate in the presence of ionising radiation. The optimal liposomal preparation was introduced into the membrane of HeLa cells that were used successfully in a cell-based SPA to detect and quantify the uptake of [14C]methionine. This thesis also describes the synthesis and subsequent polymerisation of novel poly(oxyethylene glycol)-based monomers to form a series of new polymer supports. These Poly(oxyethylene glycol)-polymer (POP) supports were evaluated for the ability to swell and mass-uptake in a variety of solvents, demonstrating that POP-supports exhibit enhanced solvent compatibilities over several commercial resins. The utility of POP-supports in solid-phase synthesis was also demonstrated successfully. The incorporation of (4’-vinyl)-4-benzyl-2,5-diphenyloxazole in varying mole percentage into the monomer composition resulted in the production of chemically functionalised scintillant-containing poly(oxyethylene glycol) polymer (POP-Sc) supports. These materials are compatible with both aqueous and organic solvents and scintillate efficiently in the presence of ionising radiation. The utility of POP-Sc supports in solid-phase synthesis and subsequent in-situ SPA to detect and quantify, in real-time, the kinetic progress of a solid-phase reaction was exemplified successfully.In addition, POP-Sc supports were used successfully both in solid-phase combinatorial synthesis of a peptide nucleic acid (PNA)-library and subsequent screening of this library for the ability to hybridise with DNA, which was labelled with a suitable radio-isotape. This data was used to identify the dependence of the number and position of complimentary codon pairs upon the extent of hybridisation. Finally, a further SPA was used to demonstrate the excellent compatibility of POP-Sc supports for use in the detection and quantification of enzyme assays conducted within the matrix of the POP-Sc support.

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Over the last twenty years, we have been continuously seeing R&D efforts and activities in developing optical fibre grating devices and technologies and exploring their applications for telecommunications, optical signal processing and smart sensing, and recently for medical care and biophotonics. In addition, we have also witnessed successful commercialisation of these R&Ds, especially in the area of fibre Bragg grating (FBG) based distributed sensor network systems and technologies for engineering structure monitoring in industrial sectors such as oil, energy and civil engineering. Despite countless published reports and papers and commercial realisation, we are still seeing significant and novel research activities in this area. This invited paper will give an overview on recent advances in fibre grating devices and their sensing applications with a focus on novel fibre gratings and their functions and grating structures in speciality fibres. The most recent developments in (i) femtosecond inscription for microfluidic/grating devices, (2) tilted grating based novel polarisation devices and (3) dual-peak long-period grating based DNA hybridisation sensors will be discussed.

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A protein microarray hybridisation system has been implemented by employing patterned hydrophobic thin films on hydrophilic substrates as a means of confinement for aqueous samples. This approach has the ability to handle, and keep separate, small sample volumes of just a few microlitres. In addition, the system is more straightforward to use than the existing multi-well gasket solution. The paper describes the fabrication method and the system is demonstrated for a model protein microarray assay. © 2011 American Institute of Physics.

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Purpose - This paper aims to provide evidence to suggest that private social and environmental reporting (i.e. one-on-one meetings between institutional investors and investees on social and environmental issues) is beginning to merge with private financial reporting and that, as a result, integrated private reporting is emerging. Design/methodology/approach - In this paper, 19 FTSE100 companies and 20 UK institutional investors were interviewed to discover trends in private integrated reporting and to gauge whether private reporting is genuinely becoming integrated. The emergence of integrated private reporting through the lens of institutional logics was interpreted. The emergence of integrated private reporting as a merging of two hitherto separate and possibly rival institutional logics was framed. Findings - It was found that specialist socially responsible investment managers are starting to attend private financial reporting meetings, while mainstream fund managers are starting to attend private meetings on environmental, social and governance (ESG) issues. Further, senior company directors are becoming increasingly conversant with ESG issues. Research limitations/implications - The findings were interpreted as two possible scenarios: there is a genuine hybridisation occurring in the UK institutional investment such that integrated private reporting is emerging or the financial logic is absorbing and effectively neutralising the responsible investment logic. Practical implications - These findings provide evidence of emergent integrated private reporting which are useful to both the corporate and institutional investment communities as they plan their engagement meetings. Originality/value - No study has hitherto examined private social and environmental reporting through interview research from the perspective of emergent integrated private reporting. This is the first paper to discuss integrated reporting in the private reporting context.

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The turn to neoliberalism in the 1990s proved decisive for Mexico, as the NAFTA project embraced by the Salinas administration entailed a re-definition of national identity, defined since the revolution as mestizo, Catholic and especially as the Other to the United States. And just as cinema was in those days a crucial discourse for this particular construction of the identity, it was in the 1990s equally instrumental to its redefinition, which largely focused on the role of migrants to the US, presented even as supplementary in the Derridean sense. In 1992, as part of these efforts, Sergio Arau directed a mockumentary which in 2004 became a feature film, ‘A Day Without a Mexican’. As would befit more the seriousness of a documentary than the excess and parody of mockumentary, the stated aim in both was to advance a social agenda, arguing the case for immigrant labour and for Mexican presence in the US more generally. The film charts what would happen in California were all Latino immigrants to suddenly disappear, arguing chaos would ensue. Given the link between cinema and modernity and the relevance of cinema for the nation as an alternative public sphere, this chapter looks at the implications of choosing mockumentary, taken by many to be a paradigmatic postmodern and hybrid form, to discuss the hybridisation of national identity in a transnational film, in the present age of globalisation.

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Valuable genetic variation for bean breeding programs is held within the common bean secondary gene pool which consists of Phaseolus albescens, P. coccineus, P. costaricensis, and P. dumosus. However, the use of close relatives for bean improvement is limited due to the lack of knowledge about genetic variation and genetic plasticity of many of these species. Characterisation and analysis of the genetic diversity is necessary among beans' wild relatives; in addition, conflicting phylogenies and relationships need to be understood and a hypothesis of a hybrid origin of P. dumosus needs to be tested. This thesis research was orientated to generate information about the patterns of relationships among the common bean secondary gene pool, with particular focus on the species Phaseolus dumosus. This species displays a set of characteristics of agronomic interest, not only for the direct improvement of common bean but also as a source of valuable genes for adaptation to climate change. Here I undertake the first comprehensive study of the genetic diversity of P. dumosus as ascertained from both nuclear and chloroplast genome markers. A germplasm collection of the ancestral forms of P. dumosus together with wild, landrace and cultivar representatives of all other species of the common bean secondary gene pool, were used to analyse genetic diversity, phylogenetic relationships and structure of P. dumosus. Data on molecular variation was generated from sequences of cpDNA loci accD-psaI spacer, trnT-trnL spacer, trnL intron and rps14-psaB spacer and from the nrDNA the ITS region. A whole genome DArT array was developed and used for the genotyping of P. dumosus and its closes relatives. 4208 polymorphic markers were generated in the DArT array and from those, 742 markers presented a call rate >95% and zero discordance. DArT markers revealed a moderate genetic polymorphism among P. dumosus samples (13% of polymorphic loci), while P. coccineus presented the highest level of polymorphism (88% of polymorphic loci). At the cpDNA one ancestral haplotype was detected among all samples of all species in the secondary genepool. The ITS region of P. dumosus revealed high homogeneity and polymorphism bias to P. coccineus genome. Phylogenetic reconstructions made with Maximum likelihood and Bayesian methods confirmed previously reported discrepancies among the nuclear and chloroplast genomes of P. dumosus. The outline of relationships by hybridization networks displayed a considerable number of interactions within and between species. This research provides compelling evidence that P. dumosus arose from hybridisation between P. vulgaris and P. coccineus and confirms that P. costaricensis has likely been involved in the genesis or backcrossing events (or both) in the history of P. dumosus. The classification of the specie P. persistentus was analysed based on cpDNA and ITS sequences, the results found this species to be highly related to P. vulgaris but not too similar to P. leptostachyus as previously proposed. This research demonstrates that wild types of the secondary genepool carry a significant genetic variation which makes this a valuable genetic resource for common bean improvement. The DArT array generated in this research is a valuable resource for breeding programs since it has the potential to be used in several approaches including genotyping, discovery of novel traits, mapping and marker-trait associations. Efforts should be made to search for potential populations of P. persistentus and to increase the collection of new populations of P. dumosus, P. albescens and P. costaricensis that may provide valuable traits for introgression into common bean and other Phaseolus crops.

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Abstract Molecular probe-based methods (Fluorescent in-situ hybridisation or FISH, Next Generation Sequencing or NGS) have proved successful in improving both the efficiency and accuracy of the identification of microorganisms, especially those that lack distinct morphological features, such as picoplankton. However, FISH methods have the major drawback that they can only identify one or just a few species at a time because of the reduced number of available fluorochromes that can be added to the probe. Although the length of sequence that can be obtained is continually improving, NGS still requires a great deal of handling time, its analysis time is still months and with a PCR step it will always be sensitive to natural enzyme inhibitors. With the use of DNA microarrays, it is possible to identify large numbers of taxa on a single-glass slide, the so-called phylochip, which can be semi-quantitative. This review details the major steps in probe design, design and production of a phylochip and validation of the array. Finally, major microarray studies in the phytoplankton community are reviewed to demonstrate the scope of the method.

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Abstract Molecular probe-based methods (Fluorescent in-situ hybridisation or FISH, Next Generation Sequencing or NGS) have proved successful in improving both the efficiency and accuracy of the identification of microorganisms, especially those that lack distinct morphological features, such as picoplankton. However, FISH methods have the major drawback that they can only identify one or just a few species at a time because of the reduced number of available fluorochromes that can be added to the probe. Although the length of sequence that can be obtained is continually improving, NGS still requires a great deal of handling time, its analysis time is still months and with a PCR step it will always be sensitive to natural enzyme inhibitors. With the use of DNA microarrays, it is possible to identify large numbers of taxa on a single-glass slide, the so-called phylochip, which can be semi-quantitative. This review details the major steps in probe design, design and production of a phylochip and validation of the array. Finally, major microarray studies in the phytoplankton community are reviewed to demonstrate the scope of the method.