924 resultados para COROT-EXO-4B


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Exchanges between the North Atlantic and the Arctic Ocean result in the most dramatic water mass conversions in the World Ocean: warm and saline Atlantic waters, flowing through the Nordic Seas into the Arctic Ocean, are modified by cooling, freezing and melting to become shallow fresh waters, ice and saline deep waters. The outflow from the Nordic Seas to the south provides the initial driving of the global thermohaline circulation cell. Knowledge of these fluxes and understanding of the modification processes is a major prerequisite for the quantification of the rate of overturning within the large circulation cells of the Arctic and the Atlantic Oceans, and is also a basic requirement for understanding the role of these ocean areas in climate variability on interannual to decadal time scales. The Fram Strait represents the only deep connection between the Arctic Ocean and the Nordic Seas. Just as the freshwater transport from the Arctic Ocean is of major influence on convection in the Nordic Seas and further south, the transport of warm and saline Atlantic water affects the water mass characteristics in the Arctic Ocean which has consequences for the internal circulation and possibly influences also ice and atmosphere. The West Spitsbergen Current carrying Atlantic Water northward. The East Greenland Current, carrying water from the Arctic Ocean southwards has a concentrated core above the continental slope. It is our aim to measure the oceanic fluxes through Fram Strait and to determine their variability in seasonal to decadal time scales. 53 CTD profiles were taken at 51 stations. Two CTD systems from Sea-Bird Electronics Inc SBE911+ were used. Mainly SN 561 with duplicate T and C sensors (temperature sensors SBE3, SN 2685 and 2678, conductivity sensors SBE4, SN 2325 and 2618 and pressure sensor Digiquartz 410K-105 SN 75659) was in service. For the control of the temperature sensors a SBE35 RT digital reversing thermometer, SN 27 was applied. The CTD was connected to a SBE32 Carousel Water Sampler, SN 273 (24 12-liter bottles). For 3 CTD-Stations (726-3, 727-1, 728-1) the Sea-Bird 911+ probe SN 485 was used with temperature sensor SBE3 SN 2460, conductivity sensor SBE4 SN 2054, pressure sensor Digiquartz 410K SN 68997 and the SBE32 Carousel Water Sampler SN 202. Additionally Benthos Altimeters Model 2110-2, SN 189 and SN 208 and Wetlabs C-Star Transmissiometers SN 403 and SN 267 were mounted on the carousels. During the cruise a total number of 184 water samples were analysed with a Guildline Autosal 8400B salinometer, and IAPSO standard seawater batch number P141, K=0.99993. 20 salinity samples were brought back to AWI for onshore analysis. The CTD sensors were calibrated before and after the cruise by Sea-Bird Electronics.

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Chromatin immunoprecipitation (ChIP) provides a means of enriching DNA associated with transcription factors, histone modifications, and indeed any other proteins for which suitably characterized antibodies are available. Over the years, sequence detection has progressed from quantitative real-time PCR and Southern blotting to microarrays (ChIP-chip) and now high-throughput sequencing (ChIP-seq). This progression has vastly increased the sequence coverage and data volumes generated. This in turn has enabled informaticians to predict the identity of multi-protein complexes on DNA based on the overrepresentation of sequence motifs in DNA enriched by ChIP with a single antibody against a single protein. In the course of the development of high-throughput sequencing, little has changed in the ChIP methodology until recently. In the last three years, a number of modifications have been made to the ChIP protocol with the goal of enhancing the sensitivity of the method and further reducing the levels of nonspecific background sequences in ChIPped samples. In this chapter, we provide a brief commentary on these methodological changes and describe a detailed ChIP-exo method able to generate narrower peaks and greater peak coverage from ChIPped material.

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Purpose: The aims of this study were to compare angle of deviation, fusional vergence measurements and fusion reserve ratio between esophoria and exophoria. Methods: A cross-sectional study was performed in children with best-corrected visual acuity of 0.0 LogMAR in either eye, compensated heterophoria within 10 prism dioptres (PD), full ocular rotations, presence of fusional vergence and stereopsis (60 seconds of arc or better). Fusional amplitudes were compared between angle of deviation (2, 4, 6, 8 and 10 PD) in esophoria and exophoria. The fusion reserve ratio was calculated (to assess the effect of the underlying angle of deviation) as fusional convergence divided by prism alternating cover test measurements. Results: Two-hundred and eleven children (7.65±1.16 years) were recruited to this study. Exophoria was most common for near (n=181; 85.8%) and distance (n=20; 9.5%). Esophoria was present in 22 children for near (10.4%) and in 1 child for distance (0.5%). No significant differences were found between fusional amplitudes and angle of deviation for near (p>0.05). Children with exophoria of 10PD had a slight, but not, significant (p=0.264) increase in fusional convergence from 2PD (19.95±5.09) to 10PD (26.67±5.77). In esophoric children the variation of fusional convergence was smaller from 2P (25.00±0.00) to 10PD (22.50±3.54) and non significant (p=0.185). The fusion reserve ratio was significantly smaller in children with higher deviations (i.e. 10PD) for both esophoria (p=0.003) and exophoria (p>0.001). The fusion reserve ratio ranged between 12.50 (2PD) and 2.25±0.35 (10PD) for esophoria and between 9.98±2.55 (2PD) and 2.67±0.58 (10PD) for exophoria. Conclusions: Angle of deviation is not an efficient measure to predict fusional amplitudes. The fusion reserve ratio appears to be a better measurement to assess the effect of the underlying angle of deviation on fusional convergence. More studies are necessary to understand better the relationship between fusion amplitudes and angle of deviation.

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The New Zealand creative sector was responsible for almost 121,000 jobs at the time of the 2006 Census (6.3% of total employment). These are divided between • 35,751 creative specialists – persons employed doing creative work in creative industries • 42,300 support workers - persons providing management and support services in creative industries • 42,792 embedded creative workers – persons engaged in creative work in other types of enterprise The most striking feature of this breakdown is the fact that the largest group of creative workers are employed outside the creative industries, i.e. in other types of businesses. Even within the creative industries, there are fewer people directly engaged in creative work than in providing management and support. Creative sector employees earned incomes of approximately $52,000 per annum at the time of the 2006 Census. This is relatively uniform across all three types of creative worker, and is significantly above the average for all employed persons (of approximately $40,700). Creative employment and incomes were growing strongly over both five year periods between the 1996, 2001 and 2006 Censuses. However, when we compare creative and general trends, we see two distinct phases in the development of the creative sector: • rapid structural growth over the five years to 2001 (especially led by developments in ICT), with creative employment and incomes increasing rapidly at a time when they were growing modestly across the whole economy; • subsequent consolidation, with growth driven by more by national economic expansion than structural change, and creative employment and incomes moving in parallel with strong economy-wide growth. Other important trends revealed by the data are that • the strongest growth during the decade was in embedded creative workers, especially over the first five years. The weakest growth was in creative specialists, with support workers in creative industries in the middle rank, • by far the strongest growth in creative industries’ employment was in Software & digital content, which trebled in size over the decade Comparing New Zealand with the United Kingdom and Australia, the two southern hemisphere nations have significantly lower proportions of total employment in the creative sector (both in creative industries and embedded employment). New Zealand’s and Australia’s creative shares in 2001 were similar (5.4% each), but in the following five years, our share has expanded (to 5.7%) whereas Australia’s fell slightly (to 5.2%) – in both cases, through changes in creative industries’ employment. The creative industries generated $10.5 billion in total gross output in the March 2006 year. Resulting from this was value added totalling $5.1b, representing 3.3% of New Zealand’s total GDP. Overall, value added in the creative industries represents 49% of industry gross output, which is higher than the average across the whole economy, 45%. This is a reflection of the relatively high labour intensity and high earnings of the creative industries. Industries which have an above-average ratio of value added to gross output are usually labour-intensive, especially when wages and salaries are above average. This is true for Software & Digital Content and Architecture, Design & Visual Arts, with ratios of 60.4% and 55.2% respectively. However there is significant variation in this ratio between different parts of the creative industries, with some parts (e.g. Software & Digital Content and Architecture, Design & Visual Arts) generating even higher value added relative to output, and others (e.g. TV & Radio, Publishing and Music & Performing Arts) less, because of high capital intensity and import content. When we take into account the impact of the creative industries’ demand for goods and services from its suppliers and consumption spending from incomes earned, we estimate that there is an addition to economic activity of: • $30.9 billion in gross output, $41.4b in total • $15.1b in value added, $20.3b in total • 158,100 people employed, 234,600 in total The total economic impact of the creative industries is approximately four times their direct output and value added, and three times their direct employment. Their effect on output and value added is roughly in line with the average over all industries, although the effect on employment is significantly lower. This is because of the relatively high labour intensity (and high earnings) of the creative industries, which generate below-average demand from suppliers, but normal levels of demand though expenditure from incomes. Drawing on these numbers and conclusions, we suggest some (slightly speculative) directions for future research. The goal is to better understand the contribution the creative sector makes to productivity growth; in particular, the distinctive contributions from creative firms and embedded creative workers. The ideas for future research can be organised into the several categories: • Understanding the categories of the creative sector– who is doing the business? In other words, examine via more fine grained research (at a firm level perhaps) just what is the creative contribution from the different aspects of the creative sector industries. It may be possible to categorise these in terms of more or less striking innovations. • Investigate the relationship between the characteristics and the performance of the various creative industries/ sectors; • Look more closely at innovation at an industry level e.g. using an index of relative growth of exports, and see if this can be related to intensity of use of creative inputs; • Undertake case studies of the creative sector; • Undertake case studies of the embedded contribution to growth in the firms and industries that employ them, by examining taking several high performing noncreative industries (in the same way as proposed for the creative sector). • Look at the aggregates – drawing on the broad picture of the extent of the numbers of creative workers embedded within the different industries, consider the extent to which these might explain aspects of the industries’ varied performance in terms of exports, growth and so on. • This might be able to extended to examine issues like the type of creative workers that are most effective when embedded, or test the hypothesis that each industry has its own particular requirements for embedded creative workers that overwhelms any generic contributions from say design, or IT.

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Online fraud occurs when an individual or a business responds in some manner to an unsolicited invitation received via the internet and suffers financial or other detrimental effects as a result. In 2010–11, the Australian Bureau of Statistics (2012) found that over 1.2 million Australians (6.7% of the population aged 15 years and over) had been a victim of personal fraud, losing approximately $1.4b in the preceding 12 months. More than half of these victims (55.7%) were contacted via the internet or email (online victimisation). In addition to monetary losses, victims of online fraud suffer serious psychological, emotional, social and even physical problems as a consequence of their victimisation. This paper explores the challenges of responding to online fraud victimisation in Australia and describes some of the specific support services that have recently emerged to support victims of this crime.

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Human cytochrome P450 (P450) enzymes are involved in the oxidation of natural products found in foods, beverages, and tobacco products and their catalytic activities can also be modulated by components of the materials. The microsomal activation of aflatoxin B1 to the exo-3,9-epoxide is stimulated by flavone and 7,8-benzoflavone, and attenuated by the flavonoid naringenin, a major component of grapefruit. P4502E1 has been demonstrated to play a potentially major role in the activation of a number of very low-molecular weight cancer suspects, including ethyl carbamate (urethan), which is present in alcoholic beverages and particularly stone brandies. The enzyme (P4502E1) is also known to be inducible by ethanol. Tobacco contains a large number of potential carcinogens. In human liver microsomes a significant role for P4501A2 can be demonstrated in the activation of cigarette smoke condensate. Some of the genotoxicity may be due to arylamines. P4501A2 is also inhibited by components of crude cigarette smoke condensate. The tobacco-specific nitrosamines are activated by a number of P450 enzymes. Of those known to be present in human liver, P4501A2, 2A6, and 2E1 can activate these nitrosamines to genotoxic products.

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Aflatoxin B1, a potently carcinogenic fungal metabolite, is converted to the biologically active form by chemical oxidation using dimethyldioxirane and enzymatically by cytochrome P450 mixed-function oxidases. Both processes give rise to mixtures of the exo- and endo-8,9-epoxides. Methanolysis studies reveal exclusive trans opening of both epoxides under neutral conditions in CH3OH and CH3OH/H2O mixtures; an SN2 mechanism is postulated. Under acidic conditions, the exo isomer gives mixtures of trans and cis solvolysis products, suggesting that the reaction is, at least in part, SN1; the endo isomer gives only the trans product. The exo isomer reacts with DNA by attack of the nitrogen atom at the 7 position of guanine on C8 of the epoxide to give the trans adduct; the endo epoxide fails to form an adduct at this or any other site in DNA. The exo isomer is strongly mutagenic in a base-pair reversion assay employing Salmonella typhimurium; the endo isomer is essentially nonmutagenic. Aflatoxin B1 and its derivatives intercalate in DNA. These results are consistent with a mechanism in which intercalation of the exo epoxide optimally orients the epoxide for an SN2 reaction with guanine but intercalation of the endo isomer places the epoxide in an orientation which precludes reaction. Thus, while the exo epoxide is a potent mutagen, the endo epoxide fails to react with DNA.

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Treatment of bromoketals 2, derived from allyl alcohols 1, with tributyltin chloride, sodium cyanoborohydride and AIBN furnishes the tetrahydrofurannulated products 3 via a 5-exo-trig radical cyclisation reaction followed by reductive cleavage of ketal 4.

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Complexes [Ru2O(O2CR)(2)(1-MeIm)(6)](ClO4)(2) (la-c), [Ru2O(O2CR)(2)(ImH)(6)](ClO4)(2) (2a,b), and [Ru2O(O2CR)(2)(4-MeImH)(6)](ClO4)(2) (3a,b) with a (mu-oxo)bis(mu-carboxylato)diruthenium(III) core have been prepared by reacting Ru2Cl(O2CR)(4) with the corresponding imidazole base, viz. 1-methylimidazole (1-MeIm), imidazole (ImH), and 4-methylimidazole (4-MeImH) in methanol, followed by treatment with NaClO4 in water (R: Me, a; C6H4-p-OMe, b; C6H4-p-Me, c). Diruthenium(III,IV) complexes [Ru2O(O2CR)(2)(1-MeIm)(6)](ClO4)(3) (R: Me, 4a; C6H4-p-OMe, 4b; C6H4-p-Me, 4c) have been prepared by one-electron oxidation of 1 in MeCN with K2S2O8 in water. Complexes la, 2a . 3H(2)O, and 4a . 1.5H(2)O have been structurally characterized. Crystal data for the complexes are as follows: la, orthorhombic, P2(1)2(1)2(1), a = 7.659(3) Angstrom, b = 22.366(3) Angstrom, c = 23.688(2) Angstrom, V = 4058(2) Angstrom(3), Z = 4, R = 0.0475, and R-w = 0.0467 for 2669 reflections with F-o > 2 sigma(F-o); 2a . 3H(2)O, triclinic, , a = 13.735(3) Angstrom, b = 14.428(4) Angstrom, c = 20.515(8) Angstrom, alpha = 87.13(3)degrees, beta = 87.61(3)degrees, gamma = 63.92(2)degrees, V = 3646(2) Angstrom(3), Z = 4, R = 0.0485 and R-w = 0.0583 for 10 594 reflections with F-o > 6 sigma(F-o); 4a . 1.5H(2)O triclinic, , a = 11.969(3) Angstrom, b = 12.090(6) Angstrom, c = 17.421(3) Angstrom, alpha = 108.93(2)degrees, beta = 84.42(2)degrees, gamma = 105.97(2)degrees, V = 2292(1) Angstrom(3), Z = 2, R = 0.0567, and R-w = 0.0705 for 6775 reflections with F-o > 6 sigma(F-o). The complexes have a diruthenium unit held by an oxo and two carboxylate ligands, and the imidazole ligands occupy the terminal sites of the core. The Ru-Ru distance and the Ru-O-oxo-Ru angle in la and 2a . 3H(2)O are 3.266(1), 3.272(1) Angstrom and 122.4(4), 120.5(2)degrees, while in 4a . 1.5H(2)O these values are 3.327(1) Angstrom and 133.6(2)degrees. The diruthenium(III) complexes 1-3 are blue in color and they exhibit an intense visible band in the range 560-575 nm. The absorption is charge transfer in nature involving the Ru(III)-d pi and O-oxo-p pi orbitals. The diruthenium(III,IV) complexes are red in color and show an intense band near 500 nm. The diruthenium(III) core readily gets oxidized with K2S2O8 forming quantitatively the diruthenium(III,IV) complex. The visible spectral record of the conversion shows an isosbestic point at 545 nm for 1 and at 535 nm for 2 and 3. Protonation of the oxide bridge by HClO4 in methanol yields the [Ru-2(mu-OH)(mu-O2CR)(2)](3+) core. The hydroxo species shows a visible band al 550 nm. The pK(a) value for la is 2.45. The protonated species are unstable. The 1-MeIm species converts to the diruthenium(III,IV) core, while the imidazole complex converts to [Ru(ImH)(6)](3+) and some uncharacterized products. Complex [Ru(ImH)(6)](ClO4)(3) has been structurally characterized. The diruthenium(III) complexes are essentially diamagnetic and show characteristic H-1 NMR spectra indicating the presence of the dimeric structure in solution. The diruthenium(III,IV) complexes are paramagnetic and display rhombic EPR spectral features. Complexes 1-3 are redox active. Complex 1 shows the one-electron reversible Ru-2(III)/(RuRuIV)-Ru-III, one-electron quasireversible (RuRuIV)-Ru-III/Ru-2(IV), and two-electron quasireversible Ru-2(III)/Ru-2(II) couples near 0.4, 1.5, and -1.0 V vs SCE In MeCN-0.1 M TBAP, respectively, in the cyclic and differential pulse voltammetric studies. Complexes 2 and 3 exhibit only reversible Ru-2(III)/(RuRuIV)-Ru-III and the quasireversible (RuRuIV)-Ru-III/Ru-2(IV) couples near 0.4 and 1.6 V vs SCE, respectively, The observation of a quasireversible one-step two-electron transfer reduction process in 1 is significant considering its relevance to the rapid and reversible Fe-2(III)/Fe-2(II) redox process known for the tribridged diiron core in the oxy and deoxy forms of hemerythrin.

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The two molecules in the asymmetric unit of adenosine-5'-carboxylic acid, C10H11N5O5, exist as zwitterions with N1 protonated and the carboxyl groups ionized. Both molecules are in an anti conformation with glycosyl torsion angles of -161.4(3) and -155.5(3)degrees. The ribose moieties adopt a C3-endo-C2-exo twist conformation. The pseudo-rotation parameters are P = 0.01(1) and 6.58(1)degrees, and tau(m) = 36.2(2) and 34.6(2)degrees, for molecules A and B, respectively. The carboxyl groups of A and B are not in the standard g(+), g(-) or t conformations. Both Watson-Crick sites, N1 and N6, of the adenine bases are involved in a pair of hydrogen bonds with the dissociated carboxyl groups, forming a cyclic tetramer. The adenine base of molecule A stacks on the ribose O4' atom of a symmetry-related B molecule at a distance of 2.88 Angstrom; the adenine base of B stacks in an analogous way at a distance of 2.91 Angstrom.

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The recent availability of international forums devoted expressly to discussing subfields of education such as curriculum studies has brought to visibility preexisting flashpoints that are not easily defused by strict adherence to definition of key terms. The difficulty of translating the term curriculum into “non”-Indo-European root languages, as well as among them, is a case in point and not just an issue of vocabulary. The difficulty of translation indexes a cleavage that is beyond-conceptual and exo-technical. Efforts to locate analogs or equivalents might suggest on the one hand, an ethnocentric preoccupation to extend the reach of a provincial concept (i.e., curriculum), while the effort to avoid or move to the side of such a preoccupation for translation might suggest structures of subjectivity that refuse co-option into foreign frames of reference. Both of these possibilities are, however, constitutive of and pointing to productive interstices from which to reengage and rephrase the weight given to subjectivity and language, to global/local divisions, and to the politics of traveling discourses in educational research.

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Diels-Alder reaction of the dienone 12, obtained by C-alkylation of sodium 2,6-dimethylphenoxide, with acrylonitrile and phenyl vinyl sulfones generate the enynes 14 and 17. Tributyltin radical addition to the terminal acetylene in 14 and 17 lead to the vinylstannanes 15 and 18 via 5-exo trig cyclisation of the resulting vinyl radical, which on oxidative cleavage furnishes the isotwistane-diones 16 and 19. Reductive desulfonylation of the diketosulfone 19 furnishes the dione 11, constituting a formal total synthesis of 2-pupukeanone 5 and 2-isocyanopupukeanone 3.

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The mode of action of xylanase and beta-glucosidase purified from the culture filtrate of Humicola lanuginosa (Griffon and Maublanc) Bunce on the xylan extracted from sugarcane bagasse and on two commercially available larchwood and oat spelt xylans, on xylooligomers and on arabinoxylooligomers was studied. While larchwood and oat spelt xylans were hydrolyzed to the same extent in 24 h, sugarcane bagasse xylan was hydrolyzed to a lesser extent in the same period. It was found that the rate of hydrolysis of xylooligomers by xylanase increased with increase in chain length, while beta-glucosidase acted rather slowly on all the oligomers tested. Xylanase exhibited predominant ''endo'' action on xylooligomers attacking the xylan chain at random while beta-glucosidase had ''exo'' action, releasing one xylose residue at a time. On arabinoxylooligomers, however, xylanase exhibited ''exo'' action. Thus, it appears that the presence of the arabinose substituent has, in some way, rendered the terminal xylose-xylose linkage more susceptible to xylanase action. It was also observed that even after extensive hydrolysis with both the enzymes, substantial amounts of the parent arabinoxylooligomer remained unhydrolyzed together with the accumulation of arabinoxylobiose. It can therefore be concluded that the presence of the arabinose substituent in the xylan chain results in linkages that offer resistance to both xylanase and beta-glucosidase action.