919 resultados para Iron industry and trade.
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Fungi, including the yeast Saccharomyces cerevisiae, lack ferritin and use vacuoles as iron storage organelles. This work explored how plant ferritin expression influenced baker's yeast iron metabolism. Soybean seed ferritin H1 (SFerH1) and SFerH2 genes were cloned and expressed in yeast cells. Both soybean ferritins assembled as multimeric complexes, which bound yeast intracellular iron in vivo and, consequently, induced the activation of the genes expressed during iron scarcity. Soybean ferritin protected yeast cells that lacked the Ccc1 vacuolar iron detoxification transporter from toxic iron levels by reducing cellular oxidation, thus allowing growth at high iron concentrations. Interestingly, when simultaneously expressed in ccc1Δ cells, SFerH1 and SFerH2 assembled as heteropolymers, which further increased iron resistance and reduced the oxidative stress produced by excess iron compared to ferritin homopolymer complexes. Finally, soybean ferritin expression led to increased iron accumulation in both wild-type and ccc1Δ yeast cells at certain environmental iron concentrations.
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Malnutrition, as a global problem, is mainly caused by low level of mineral elements in staple food (deficient soil). Biofortification is based on selection of genotypes with enhanced concentration of mineral elements in grain, as well as decreased concentration of substances which interfere bioavailability of mineral elements in gut (like phytic acid), and increased content of substances that increase availability (such as β-carotene). The experiment with 51 maize ( Zea mays L.) inbred lines with different heterotic background was set up in order to evaluate chemical composition of grain and to determine the relations between phytic acid (PA), β-carotene, and mineral elements: Mg, Fe, Mn, and Zn. The highest average phytate, β-carotene, Fe, and Mn content was found in grain of inbreds from Lancaster heterotic group. The highest content of Mg was in grain of Independent source and Zn in grain of BSSS group. Increased level of Fe and Mn in Lancaster lines could be partially affected by higher PA content in grain, while increased β-carotene content could improve Mn and Zn availability from grain of BSSS genotypes and Mg availability from Lancaster inbreds. It is important to underline that PA reduction is followed by Zn content increase in grain of Lancaster heterotic group, as well as that variations in Mg, Fe, and Mn contents are independent on PA status in inbreds from Independent source, indicating that the genotypes with higher Mg, Fe and Mn status from this group could serve as favorable source for improved Mg, Fe, and Mn absorption.
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Description based on: June 1984; title from caption.
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Description based on: Sept. 1990; title from caption.
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We compare auctioning and grandfathering as allocation mechanisms of emission permits when there is a secondary market with market power and firms have private information on their own abatement technologies. Based on real-life cases such as the EU ETS, we consider a multi-unit, multi-bid uniform auction. At the auction, each firm anticipates its role in the secondary market, either as a leader or a follower. This role affects each firms’ valuation of the permits (which are not common across firms) as well as their bidding strategies and it precludes the auction from generating a cost-effective allocation of permits, as it occurs in simpler auction models. Auctioning tends to be more cost-effective than grandfathering when the firms’ abatement cost functions are sufficiently different from one another, especially if the follower has lower abatement costs than the leader and the dispersion of the marginal costs is large enough.
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This work reports the in vitro activity against Plasmodium falciparum blood forms (W2 clone, chloroquine-resistant) of tamoxifen-based compounds and their ferrocenyl (ferrocifens) and ruthenocenyl (ruthenocifens) derivatives, as well as their cytotoxicity against HepG2 human hepatoma cells. Surprisingly with these series, results indicate that the biological activity of ruthenocifens is better than that of ferrocifens and other tamoxifen-like compounds. The synthesis of a new metal-based compound is also described. It was shown, for the first time, that ruthenocifens are good antiplasmodial prototypes. Further studies will be conducted aiming at a better understanding of their mechanism of action and at obtaining new compounds with better therapeutic profile.
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Controlling iron distribution is important for all organisms, and is key in bacterial pathogenesis. It has long been understood that cystic fibrosis (CF) patient sputum contains elevated iron concentrations. However, anaerobic bacteria have been isolated from CF sputum and hypoxic zones in sputum have been measured. Because ferrous iron [Fe(II)] is stable in reducing, acidic conditions, it could exist in the CF lung. I show that a two-component system, BqsRS, specifically responds to Fe(II) in the CF pathogen, Pseudomonas aeruginosa. Concurrently, a clinical study found that Fe(II) is present in CF sputum at all stages of lung function decline. Fe(II), not Fe(III) correlates with patients in the most severe disease state. Furthermore, transcripts of the newly identified BqsRS were detected in sputum. Two component systems are the main method bacteria interact with their extracellular environment. A typical two-component system contains a sensor histidine kinase, which upon activation phosphorylates a response regulator that then acts as a transcription factor to elicit a cellular response to stimuli. To explore the mechanism of BqsRS, I describe the Fe(II)-sensing RExxE motif in the sensor BqsS and determine the consensus DNA sequence BqsR binds. With the BqsR binding sequence, I identify novel regulon members through bioinformatic and molecular biology techniques. From the predicted function of new BqsR regulon members, I find that Fe(II) elicits a response that globally protects the cells against cationic stressors, including clinically relevant antibiotics. Subsequently, I use BqsR as a case study to determine if promoter outputs can accurately be predicted based only on a deep understanding of a transcriptional activator’s operator or if a broader regulatory context is required for accurate predictions at all genomic loci. This work highlights the importance of Fe(II) as a (micro)environmental factor, even in conditions typically thought of as aerobic. Since the presence of Fe(II) can alter P. aeruginosa’s antibiotic susceptibility, combining the current strategy of targeting Fe(III) with a new approach targeting Fe(II) may help eradicate infections in the CF lung in the future.
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Resumen Este estudio analiza importantes acciones legislativas del 2002 que afectarán sustancialmente las negociaciones comerciales con Estados Unidos; examina, asimismo, la protección de importaciones de ese país con respecto a productos agrícolas que serán críticos en las negociaciones con los países centroamericanos. Las acciones legislativas mencionadas fueron la aprobación del Proyecto de ley Agrícola del 2002 y la aprobación de la Autorización de Promoción Legal, que provee tratamiento del ‘trámite rápido’ de los acuerdos comerciales…
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This paper analyses the extent to which intensive investments in public capital may have had an unfavourable impact on the regional trade balances across the 20 Italian regions. Our working hypothesis is that investments in public capital, while stimulating the demand for tradables across the regions, may have a limited positive impact on the supply of tradables in regions characterised by relatively low productivity like the South of Italy (or Mezzogiorno). The empirical results are consistent with our expectations and suggest that programs of investments in public capital should be accompanied by additional policy measures that can remove the structural factors that hamper the total factor productivity growth in specific areas. © Springer-Verlag 2008.
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Because of their relative simplicity and the barriers to gene flow, islands are ideal systems to study the distribution of biodiversity. However, the knowledge that can be extracted from this peculiar ecosystem regarding epidemiology of economically relevant diseases has not been widely addressed. We used information available in the scientific literature for 10 old world islands or archipelagos and original data on Sicily to gain new insights into the epidemiology of the Mycobacterium tuberculosis complex (MTC). We explored three nonexclusive working hypotheses on the processes modulating bovine tuberculosis (bTB) herd prevalence in cattle and MTC strain diversity: insularity, hosts and trade. Results suggest that bTB herd prevalence was positively correlated with island size, the presence of wild hosts, and the number of imported cattle, but neither with isolation nor with cattle density. MTC strain diversity was positively related with cattle bTB prevalence, presence of wild hosts and the number of imported cattle, but not with island size, isolation, and cattle density. The three most common spoligotype patterns coincided between Sicily and mainland Italy. However in Sicily, these common patterns showed a clearer dominance than on the Italian mainland, and seven of 19 patterns (37%) found in Sicily had not been reported from continental Italy. Strain patterns were not spatially clustered in Sicily. We were able to infer several aspects of MTC epidemiology and control in islands and thus in fragmented host and pathogen populations. Our results point out the relevance of the intensity of the cattle commercial networks in the epidemiology of MTC, and suggest that eradication will prove more difficult with increasing size of the island and its environmental complexity, mainly in terms of the diversity of suitable domestic and wild MTC hosts.
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This is the first of three books about the history of Geoffrey Lynfield's family. It is about four Lilienfeld brothers--Geoffrey Lynfield's grandfather and his brothers. They were born in the Jewish enclave of Marburg and ended up in South Africa when and where the first diamonds were discovered. The manuscript also includes photographs and documents.
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The bulk of the collection consists of correspondence to Hendricks & Brothers, 1833[?]-1851. Also included are business cards from various Hendricks-Tobias family enterprises, correspondence to Harmon Hendricks, and correspondence to several members of the Tobias family. The collection is arranged in four series. See finding aid for more information.
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Strategic reviews of the Irish Food and Beverage Industry have consistently emphasised the need for food and beverage firms to improve their innovation and marketing capabilities, in order to maintain competitiveness in both domestic and overseas markets. In particular, the functional food and beverages market has been singled out as an extremely important emerging market, which Irish firms could benefit from through an increased technological and market orientation. Although health and wellness have been the most significant drivers of new product development (NPD) in recent years, failure rates for new functional foods and beverages have been reportedly high. In that context, researchers in the US, UK, Denmark and Ireland have reported a marked divergence between NPD practices within food and beverage firms and normative advice for successful product development. The high reported failure rates for new functional foods and beverages suggest a failure to manage customer knowledge effectively, as well as a lack of knowledge management between functional disciplines involved in the NPD process. This research explored the concept of managing customer knowledge at the early stages of the NPD process, and applied it to the development of a range of functional beverages, through the use of advanced concept optimisation research techniques, which provided for a more market-oriented approach to new food product development. A sequential exploratory research design strategy using mixed research methods was chosen for this study. First, the qualitative element of this research investigated customers’ choice motives for orange juice and soft drinks, and explored their attitudes and perceptions towards a range of new functional beverage concepts through a combination of 15 in-depth interviews and 3 focus groups. Second, the quantitative element of this research consisted of 3 conjoint-based questionnaires administered to 400 different customers in each study in order to model their purchase preferences for chilled nutrient-enriched and probiotic orange juices, and stimulant soft drinks. The in-depth interviews identified the key product design attributes that influenced customers’ choice motives for orange juice. The focus group discussions revealed that groups of customers were negative towards the addition of certain functional ingredients to natural foods and beverages. K-means cluster analysis was used to quantitatively identify segments of customers with similar preferences for chilled nutrient-enriched and probiotic orange juices, and stimulant soft drinks. Overall, advanced concept optimisation research methods facilitate the integration of the customer at the early stages of the NPD process, which promotes a multi-disciplinary approach to new food product design. This research illustrated how advanced concept optimisation research methods could contribute towards effective and efficient knowledge management in the new food product development process.