878 resultados para Sugar and ethanol industry


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Rapid pollen tube growth requires a high rate of sugar metabolism to meet energetic and biosynthetic demands. Previous work on pollen sugar metabolism showed that tobacco pollen carry out efficient ethanolic fermentation concomitantly with a high rate of respiration (Bucher et al ., 1995). Here we show that the products of fermentation, acetaldehyde and ethanol, are further metabolised in a pathway that bypasses mitochondrial PDH. The enzymes involved in this pathway are pyruvate decarboxylase, aldehyde dehydrogenase and acetyl-CoA synthetase. Radiolabelling experiments show that during tobacco pollen tube growth label of C-14-ethanol is incorporated into CO2 as well as into lipids and other higher molecular weight compounds. A role for the glyoxylate cycle appears unlikely since activity of malate synthase, a key enzyme of the glyoxylate cycle, could not be detected.

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Tricyclo-DNA (tcDNA) is a sugar- and backbone-modified analogue of DNA that is currently tested as antisense oligonucleotide for the treatment of Duchenne muscular dystrophy. The name tricyclo-DNA is derived from the modified sugar-moiety: the deoxyribose is extended to a three-membered ring system. This modification is designed to limit the flexibility of the structure, thus giving rise to entropically stabilized hybrid duplexes formed between tcDNA and complementary DNA or RNA oligonucleotides. While the structural modifications increase the biostability of the therapeutic agent, they also render the oligonucleotide inaccessible to enzyme-based sequencing methods. Tandem mass spectrometry constitutes an alternative sequencing technique for partially and fully modified oligonucleotides. For reliable sequencing, the fragmentation mechanism of the structure in question must be understood. Therefore, the presented work evaluates the effect of the modified sugar-moiety on the gas-phase dissociation of single stranded tcDNA. Moreover, our experiments reflect the exceptional gas-phase stability of hybrid duplexes that is most noticeable in the formation of truncated duplex ions upon collision-induced dissociation. The stability of the duplex arises from the modified sugar-moiety, as the rigid structure of the tcDNA single strand minimizes the change of the entropy for the annealing. Moreover, the tc-modification gives rise to extended conformations of the nucleic acids in the gas-phase, which was studied by ion mobility spectrometry-mass spectrometry.

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Antisense oligonucleotides deserve great attention as potential drug candidates for the treatment of genetic disorders. For example, muscle dystrophy can be treated successfully in mice by antisense-induced exon skipping in the pre-mRNA coding for the structural protein dystrophin in muscle cells. For this purpose a sugar- and backbone-modified DNA analogue was designed, in which a tricyclic ring system substitutes the deoxyribose. These chemical modifications stabilize the dimers formed with the targeted RNA relative to native nucleic acid duplexes and increase the biostability of the antisense oligonucleotide. While evading enzymatic degradation constitutes an essential property of antisense oligonucleotides for therapeutic application, it renders the oligonucleotide inaccessible to biochemical sequencing techniques and requires the development of alternative methods based on mass spectrometry. The set of sequences studied includes tcDNA oligonucleotides ranging from 10 to 15 nucleotides in length as well as their hybrid duplexes with DNA and RNA complements. All samples were analyzed on a LTQ Orbitrap XL instrument equipped with a nano-electrospray source. For tandem mass spectrometric experiments collision-induced dissociation was performed, using helium as collision gas. Mass spectrometric sequencing of tcDNA oligomers manifests the applicability of the technique to substrates beyond the scope of enzyme-based methods. Sequencing requires the formation of characteristic backbone fragments, which take the form of a-B- and w-ions in the product ion spectra of tcDNA. These types of product ions are typically associated with unmodified DNA, which suggests a DNA-like fragmentation mechanism in tcDNA. The loss of nucleobases constitutes the second prevalent dissociation pathway observed in tcDNA. Comparison of partially and fully modified oligonucleotides indicates a pronounced impact of the sugar-moiety on the base loss. As this event initiates cleavage of the backbone, the presented results provide new mechanistic insights into the fragmentation of DNA in the gas-phase. The influence of the sugar-moiety on the dissociation extends to tcDNA:DNA and tcDNA:RNA hybrid duplexes, where base loss was found to be much more prominent from sugar-modified oligonucleotides than from their natural complements. Further prominent dissociation channels are strand separation and backbone cleavage of the single strands, as well as the ejection of backbone fragments from the intact duplex. The latter pathway depends noticeably on the base sequence. Moreover, it gives evidence of the high stability of the hybrid dimers, and thus directly reflects the affinity of tcDNA for its target in the cell. As the cellular target of tcDNA is a pre-mRNA, the structure was designed to discriminate RNA from DNA complements, which could be demonstrated by mass spectrometric experiments.

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The addition of oxygenated renewable fuels, such as ethanol or ethyl tert-butyl ether (ETBE) to standard gasoline may be necessary to comply with some environmental directives but could also prevent compliance with some fuel regulations and could also seriously change engine performance. From this point of view, the Reid Vapour Pressure (RVP), the distillation curve, the oxygen content and the density belong to the group of the most relevant parameters. This study evaluates the influence of the simultaneous addition of ethanol and ETBE on some physical properties of engine gasoline. The main conclusion is that the simultaneous addition of ETBE and ethanol changes the RVP, the distillation curve and the density in a way that can affect engine operation and the mandatory EN 228 and ASTM D4814 standards. Some opposite properties of both oxygenates could help to increase the renewable energy content without preventing compliance with these regulations.

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The goal of this research was to resolve the hypoxic and anoxic responses of maize (Zea mays) sucrose (Suc) synthases known to differ in their sugar regulation. The two maize Suc synthase genes, Sus1 and Sh1, both respond to sugar and O2, and recent work suggests commonalities between these signaling systems. Maize seedlings (NK508 hybrid, W22 inbred, and an isogenic sh1-null mutant) were exposed to anoxic, hypoxic, and aerobic conditions (0, 3, and 21% O2, respectively), when primary roots had reached approximately 5 cm. One-centimeter tips were excised for analysis during the 48-h treatments. At the mRNA level, Sus1 was rapidly up-regulated by hypoxia (approximately 5-fold in 6 h), whereas anoxia had less effect. In contrast, Sh1 mRNA abundance increased strongly under anoxia (approximately 5-fold in 24 h) and was much less affected by hypoxia. At the enzyme level, total Suc synthase activity rose rapidly under hypoxia but showed little significant change during anoxia. The contributions of SUS1 and SH1 activities to these responses were dissected over time by comparing the sh1-null mutant with the isogenic wild type (Sus+, Sh1+). Sh1-dependent activity contributed most markedly to a rapid protein-level response consistently observed in the first 3 h, and, subsequently, to a long-term change mediated at the level of mRNA accumulation at 48 h. A complementary midterm rise in SUS1 activity varied in duration with genetic background. These data highlight the involvement of distinctly different genes and probable signal mechanisms under hypoxia and anoxia, and together with earlier work, show parallel induction of “feast and famine” Suc synthase genes by hypoxia and anoxia, respectively. In addition, complementary modes of transcriptional and posttranscriptional regulation are implicated by these data, and provide a mechanism for sequential contributions from the Sus1 and Sh1 genes during progressive onset of naturally occurring low-O2 events.

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Mode of access: Internet.

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This paper examines the role of creative resources in the emergence of the Japanese video game industry. We argue that creative resources nurtured by popular cartoons and animation sector, combined with technological knowledge accumulated in the consumer electronics industry, facilitated the emergence of successful video game industry in Japan. First we trace the development of the industry from its origin to the rise of platform developers and software publishers. Then, knowledge and creative foundations that influenced the developmental trajectory of this industry are analyzed, with links to consumer electronics and in regards to cartoons and animation industry.

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This thesis looks at the UK onshore oil and gas production industry and follows the history of a population of firms over a fifteen-year period following the industry's renaissance. It examines the linkage between firm survival, selection pressures and adaptation responses at the firm level, especially the role of discretionary adaptation, specifically exploration and exploitation strategies.Taking a Realist approach and using quantitative and qualitative methods for triangulation on a new data base derived from archival data, as well as informant interviews, it tests seven hypotheses' about post-entry survival of firms. The quantitative findings suggest that firm survival within this industry is linked to discretionary adaptation, when measured at the firm level, and to a mixture of selection and adaptation forces when measured for each firm for each individual year. The qualitative research suggests that selection factors dominate. This difference in views is unresolved. However the small, sparse population and the nature of the oil and gas industry compared with other common research contexts such as manufacturing or service firms suggests the results be treated with caution as befits a preliminary investigation. The major findings include limited support for the theory that the external environment is the major determinant of firm survival, though environment components affect firms differentially; resolution of apparent literature differences relating to the sequencing of exploration and exploitation and potential tangible evidence of coevolution. The research also finds that, though selection may be considered important by industry players, discretionary adaptation appears to play the key role, and that the key survival drivers for thispopulation are intra-industry ties, exploitation experience and a learning/experience component. Selection has a place, however, in determining the life-cycle of the firm returning to be a key survival driver at certain ages of the firm inside the industry boundary.

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This paper surveys the literature on scale and scope economies in the water and sewerage industry. The magnitude of scale and scope economies determines the cost efficient configuration of any industry. In the case of a regulated sector, reliable estimates of these economies are relevant to inform reform proposals that promote vertical (un)bundling and mergers. The empirical evidence allows some general conclusions. First, there is considerable evidence for the existence of vertical scope economies between upstream water production and distribution. Second, there is only mixed evidence on the existence of (dis)economies of scope between water and sewerage activities. Third, economies of scale exist up to certain output level, and diseconomies of scale arise if the company increases its size beyond this level. However, the optimal scale of utilities also appears to vary considerably between countries. Finally, we briefly consider the implications of our findings for water pricing and point to several directions for necessary future empirical research on the measurement of these economies, and explaining their cross country variation.

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Purpose - Studies the implementation of lean supply and partnership relationships in the UK food and farming industry to assess if these types of interventions are effective. Design/methodology/approach - Reviews the challenges affecting the UK supply chain for red meat. Describes the initiatives that were set up to develop a lean supply chain management approach and examines their application in the UK pig and beef industries. Assesses if these changes benefited all participants in the supply chains. Uses semi-structured interviews with key actors in each stage of the supply chain to do this, identifying the power relations within the supply chains and how these affected the outcomes for those participating in the chain. Findings - Concludes that lean initiatives were appropriate for the pig industry but were of limited value for the beef industry. Even within the pig industry, highlights that benefits were not shared equally, with producers, in particular, losing out. Lastly, points out that lean supply chain management is unlikely to be appropriate operationally and commercially in all circumstances in one industry. Argues for a differentiated policy approach and sets out a framework which enables decision makers to select industrial policy options. Research limitations/ implications - Describes the analysis and the framework developed from it. Originality/value - Assesses the effectiveness of lean supply chain management.

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In the discussion - Travel Marketing: Industry Relationships and Benefits - by Andrew Vladimir, Visiting Assistant Professor, School of Hospitality Management at Florida International University, the author initially states: “A symbiotic relationship exists among the various segments of the travel and tourism industry. The author has solicited the thinking of 37experts and leaders in the field in a book dealing with these relationships and how they can be developed to benefit the industry. This article provides some salient points from those contributors.” This article could be considered a primer on networking for the hospitality industry. It has everything to do with marketing and the relationships between varied systems in the field of travel and tourism. Vladimir points to instances of success and failure in marketing for the industry at large. And there are points of view from thirty-seven contributing sources here. “Miami Beach remains a fitting example of a leisure product that has been unable to get its act together,” Vladimir shares a view. “There are some first class hotels, a few good restaurants, alluring beaches, and a splendid convention center, but there is no synergism between them, no real affinity, and so while visitors admire the Fontainebleau Hilton and enjoy the food at Joe's Stone Crabs, the reputation of Miami Beach as a resort remains sullied,” the author makes a point. In describing cohesiveness between exclusive systems, Vladimir says, “If each system can get a better understanding of the inner workings of neighboring related systems, each will ultimately be more successful in achieving its goals.” The article is suggesting that exclusive systems aren’t really exclusive at all; or at least they shouldn’t be. In a word – competition – drives the market, and in order for a property to stay afloat, aggressive marketing integrated with all attendant resources is crucial. “Tisch [Preston Robert Tisch, currently – at the time of this writing - the Postmaster General of the United States and formerly president of Lowe’s Hotels and the New York Visitors and Convention Bureau], in talking about the need for aggressive marketing says: “Never...ever...take anything for granted. Never...not for a moment...think that any product or any place will survive strictly on its own merits.” Vladimir not only sources several knowledgeable representatives in the field of hospitality and tourism, but he also links elements as disparate as real estate, car rental, cruise and airlines, travel agencies and traveler profiles to illustrate his points on marketing integration. In closing, Vladimir quotes the Honorable Donna Tuttle, Undersecretary of Commerce for Travel and Tourism, “Uniting the components of this industry in an effective marketing coalition that can compete on an equal footing with often publicly-owned foreign tourism conglomerates and multi-national consortia must be a high priority as the United States struggles to maintain and expand its share of a rapidly changing global market.”

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Background: Dietary behaviour interventions have the potential to reduce diet-related disease. Ample opportunity exists to implement these interventions in the workplace. The overall aim is to assess the effectiveness and cost-effectiveness of complex dietary interventions focused on environmental dietary modification alone or in combination with nutrition education in large manufacturing workplace settings. Methods/design: A clustered controlled trial involving four large multinational manufacturing workplaces in Cork will be conducted. The complex intervention design has been developed using the Medical Research Council's framework and the National Institute for Health and Clinical Excellence (NICE) guidelines and will be reported using the TREND statement for the transparent reporting of evaluations with non-randomized designs. It will draw on a soft paternalistic 'nudge' theoretical perspective. It will draw on a soft paternalistic "nudge" theoretical perspective. Nutrition education will include three elements: group presentations, individual nutrition consultations and detailed nutrition information. Environmental dietary modification will consist of five elements: (a) restriction of fat, saturated fat, sugar and salt, (b) increase in fibre, fruit and vegetables, (c) price discounts for whole fresh fruit, (d) strategic positioning of healthier alternatives and (e) portion size control. No intervention will be offered in workplace A (control). Workplace B will receive nutrition education. Workplace C will receive nutrition education and environmental dietary modification. Workplace D will receive environmental dietary modification alone. A total of 448 participants aged 18 to 64 years will be selected randomly. All permanent, full-time employees, purchasing at least one main meal in the workplace daily, will be eligible. Changes in dietary behaviours, nutrition knowledge, health status with measurements obtained at baseline and at intervals of 3 to 4 months, 7 to 9 months and 13 to 16 months will be recorded. A process evaluation and cost-effectiveness economic evaluation will be undertaken. Discussion: A 'Food Choice at Work' toolbox (concise teaching kit to replicate the intervention) will be developed to inform and guide future researchers, workplace stakeholders, policy makers and the food industry. Trial registration: Current Controlled Trials, ISRCTN35108237.

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Preliminary data on dissolved organic carbon (DOC) and dissolved sugars in interstitial water samples collected at Sites 618, 619, and 623 of Deep Sea Drilling Project Leg 96 are presented. At Site 618 in Orca Basin, the DOC content of the interstitial water peaks in the hypersaline sulfate reduction zone. The sugar content reaches a maximum and the DOC content begins to decrease at the depth of methane gas generation. Below that depth, the sugar and DOC contents are about constant. At Site 619 in Pigmy Basin, the DOC content increases slightly with depth in the sulfate reduction and the methane fermentation zones. The sugar content is lower in the sulfate reduction zone than in the methane fermentation zone; sugar concentration increases and fluctuates with methane gas percentages within the methane fermentation zone. At Site 623 in the lower fan region of the Mississippi Fan, there is no sulfate reduction zone. The DOC and sugar contents of the interstitial water are almost constant with depth.

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O bioetanol constitui uma alternativa renovável aos combustíveis fósseis. Contudo, o bioetanol de primeira geração, produzido a partir de matérias-primas alimentares, desencadeou sérios problemas económicos e sociais, pelo que é fundamental encontrar estratégias que permitam a viabilidade comercial do bioetanol de segunda geração, produzido a partir de matérias-primas lenho-celulósicas. O licor de cozimento ao sulfito ácido de árvores folhosas (HSSL) é um subproduto da indústria papeleira que, devido ao seu elevado conteúdo em açúcares, pode ser utilizado como substrato para a produção de bioetanol de segunda geração. No entanto, a maior fração dos açúcares do HSSL é composta por pentoses. Por isso, a fermentação do HSSL é realizada pela levedura Scheffersomyces stipitis, pois esta é capaz de fermentar tanto as hexoses como as pentoses. Todavia, a S. stipitis só produz etanol sob condições microaerófilas, pelo que o maior desafio da produção de bioetanol por S. stipitis reside no estabelecimento das condições ótimas de arejamento. Este trabalho teve assim por objetivo estabelecer uma estratégia de arejamento que permita a eficiente produção de bioetanol a partir de HSSL por S. stipitis C4, a qual é uma estirpe adaptada a este substrato. Deste modo, foram realizados ensaios em Erlenmeyer, de modo a caracterizar o crescimento da S. stipitis C4, e ensaios em biorreator, com vista a estudar a produção de etanol por S. stipitis C4 em duas estratégias de arejamento diferentes. Na primeira estratégia foi usado apenas um único estágio de arejamento, com controlo da tensão de oxigénio dissolvido, DOT (%), e na segunda estratégia foram usados dois estágios de arejamento, com controlo da DOT no primeiro estágio e com restrição de oxigénio no segundo estágio. Nos ensaios em Erlenmeyer com HSSL o crescimento da S. stipitis C4 foi completamente inibido. Por sua vez, nos ensaios em biorreator com um único estágio de arejamento o controlo da DOT não permitiu a produção de etanol. No entanto, nos ensaios com dois estágios de arejamento em meio sintético foi possível produzir etanol de forma eficiente. Nesta estratégia, a utilização de um maior valor de DOT no primeiro estágio de arejamento permitiu aumentar a taxa específica de crescimento máxima e o rendimento em biomassa do primeiro estágio. Para além disso, a utilização de um maior valor de DOT no primeiro estágio também permitiu aumentar a produtividade em etanol durante o segundo estágio de arejamento. Por sua vez, no segundo estágio de arejamento verificou-se que a restrição de oxigénio evitou a reassimilação de etanol pela S. stipitis C4. Deste modo, os melhores resultados para a produção de etanol foram obtidos com controlo da DOT a 50% durante o primeiro estágio e com 0 mLAr.min-1 e 250 rpm durante o segundo estágio de arejamento. A aplicação desta estratégia de arejamento a 60% HSSL/40% meio sintético permitiu obter, no primeiro estágio de arejamento, uma taxa específica de crescimento máxima de 0,17 h-1, o que demonstra que a elevada disponibilidade de oxigénio durante o primeiro estágio aumenta a tolerância da S. stipitis C4 aos inibidores. Para além disso, a taxa volumétrica de produção de etanol e o rendimento em etanol de toda a fermentação foi de respetivamente de 0,03 g.L-1.h-1 e 0,38 g.g-1. Assim, a elevada eficiência de conversão dos açúcares em etanol (74,4%) demostra que a fermentação com dois estágios de arejamento constitui uma estratégia promissora para a produção de bioetanol de segunda geração a partir de HSSL.