977 resultados para 6-3-5 method


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To investigate the dynamics of guanosine 3′,5′-cyclic monophosphate (cGMP) in single living cells, we constructed genetically encoded, fluorescent cGMP indicators by bracketing cGMP-dependent protein kinase (cGPK), minus residues 1–77, between cyan and yellow mutants of green fluorescent protein. cGMP decreased fluorescence resonance energy transfer (FRET) and increased the ratio of cyan to yellow emissions by up to 1.5-fold with apparent dissociation constants of ≈2 μM and >100:1 selectivity for cGMP over cAMP. To eliminate constitutive kinase activity, Thr516 of cGPK was mutated to Ala. Emission ratio imaging of the indicators transfected into rat fetal lung fibroblast (RFL)-6 showed cGMP transients resulting from activation of soluble and particulate guanylyl cyclase, respectively, by nitric oxide (NO) and C-type natriuretic peptide (CNP). Whereas all naive cells tested responded to CNP, only 68% responded to NO. Both sets of signals showed large and variable (0.5–4 min) latencies. The phosphodiesterase (PDE) inhibitor 3-isobutyl-1-methylxanthine (IBMX) did not elevate cGMP on its own but consistently amplified responses to NO or CNP, suggesting that basal activity of guanylate cyclase is very low and emphasizing the importance of PDEs in cGMP recycling. A fraction of RFL cells showed slowly propagating tides of cGMP spreading across the cell in response to delocalized application of NO. Biolistically transfected Purkinje neurons showed cGMP responses to parallel fiber activity and NO donors, confirming that single-cell increases in cGMP occur under conditions appropriate to cause synaptic plasticity.

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3. Aus der "Dialektik der Aufklärung"; Kapitel: "Juliette oder Aufklärung und Moral". Typoskript mit dem Titel "Aufklärung und Rigorismus", mit handschriftlichen Korrekturen, 52 Blatt (2 Exemplare); 4. Aus der "Dialektik der Aufklärung"; Kapitel: "Kulturindustrie". Typoskript mit dem Titel "Das Schema der Massenkultur":; 4a) Typoskript mit handschriftlichen Korrekturen, 67 Blatt; 4b) Typoskript mit eigenen Korrekturen, 106 Blatt; 5. - 110. Gedruckte und ungedruckte Aufzeichnungen und Entwürfe zur "Dialektik der Aufklärung: Sammlungen A, B, C, D, die teilweise identisch sind; 5. - 42. Sammlung A: "Aphorismen"; 5. "Zum Problem der Bedürfnisse". Typoskript, 5 Blatt; 6. "Mensch und Tier". Typoskript mit eigenen Korrekturen, 12 Blatt; 7. "Propaganda". Typoskript, 2 Blatt; 8. "Straftheorie". Typoskript mit eigenen Korrekturen, 3 Blatt; 9. "Dichtung und Moral". Typoskript mit eigenen Korrekturen, 5 Blatt; 10. "Zur Genese der Dummheit". Typoskript, 3 Blatt; 11. "Interesse am Körper". Typoskript mit eigenen Korrekturen, 6 Blatt; 12. "Philosophie und Arbeitsteilung". Typoskript, 3 Blatt; 13. "Widersprüche". Typoskript, 4 Blatt; 14. "Geschichte der amerikanischen Arbeiterschaft". Typoskript, 1 Blatt; 15. "Feind". Typoskript, 2 Blatt; 16. "Gezeichnet". Typoskript mit eigenen Korrekturen, 2 Blatt; 17. "Erkenntnis und Sprache". Typoskript, 1 Blatt; 18. "Unmöglichkeit der Dichtung". Typoskript, 1 Blatt; 19. "Erbsünde und Kopula". Typoskript, 2 Blatt; 20. "Die Einseitigkeit der Negativität". Typoskript, 2 Blatt [= "Für Voltaire" in der "Dialektik der Aufklärung"]; 21. "Klassifikation". Typoskript mit eigenen Ergänzungen, 1 Blatt; 22. "Jüdischer Charakter". Typoskript mit eigenen Korrekturen, 1 Blatt; 23. "Lawine". Typoskript mit eigenen Korrekturen, 2 Blatt; 24. "Solidarität". Typoskript mit eigenen Korrekturen, 2 Blatt; 25. "Bewußtsein". Typoskript, 1 Blatt; 26. "Gegen Bescheidwissen". Typoskript, 1 Blatt; 27. "Der Gedanke". Typoskript, 1 Blatt; 28. "Quand-même". Typoskript, 2 Blatt; 29. "Leeres Erschrecken". Typoskript mit eigenen Korrekturen, 2 Blatt; 30. "Haupt- und Nebensatz". Typoskript, 3 Blatt; 31. "Verwandlung der Idee in Herrschaft". Typoskript mit eigenen Korrekturen, 5 Blatt; 32. "Isolierung durch Verkehr". Typoskript, 1 Blatt; 33. "Kampf und Gewaltlosigkeit". Typoskript, 6 Blatt; 34. "Zwei Welten". Typoskript, 2 Blatt; 35. "Zur Theorie der Gespenster". Typoskript, 1 Blatt; 36. "Notiz" [= "Umschlag der idealistischen Dialektik"]. Typoskript, 1 Blatt; 37. "Massengesellschaft". Typoskript, 1 Blatt; 38. "Tierpsychologie". Typoskript, 1 Blatt; 39. "Denkmale der Humanität". Typoskript mit eigenen Korrekturen, 1 Blatt; 40. "Physiognomik". Typoskript mit eigenen Korrekturen, 1 Blatt; 41. "Die Rackets und der Geist". Typoskript mit eigenen Korrekturen, 7 Blatt; 42. "Altmodisches Problem". Typoskript mit eigenen Korrekturen, 2 Blatt;

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Gasoline oxygenates (MTBE, methyl tert-butyl ether; DIPE, di-isopropyl ether; ETBE, ethyl tert-butyl ether; TAME, tert-amyl ether) are added to gasoline to boost octane and enhance combustion. The combination of large scale use, high water solubility and only minor biodegradability has now resulted in a significant gasoline oxygenate contamination occurring in surface, ground, and drinking water systems. Combination of hydroxyl radical formation and the pyrolytic environment generated by ultrasonic irradiation (665 kHz) leads to the rapid degradation of MTBE and other gasoline oxygenates in aqueous media. ^ The presence of oxygen promotes the degradation processes by rapid reaction with carbon centered radicals indicating radical processes involving O 2 are significant pathways. A number of the oxidation products were identified. The formation of products (alcohols, ketones, aldehydes, esters, peroxides, etc) could be rationalized by mechanisms which involve hydrogen abstraction by OH radical and/or pyrolysis to form carboncentered radicals which react with oxygen and follow standard oxidation chain processes. ^ The reactions of N-substituted R-triazolinediones (RTAD; R = CH 3 or phenyl) have attracted considerable interest because they exhibit a number of unusual mechanistic characteristics that are analogous to the reactions of singlet oxygen (1O2) and offer an easy way to provide C-N bond(s) formation. The reactions of triazolinedione with olefins have been widely studied and aziridinium imides are generally accepted to be the reactive intermediates. ^ We observed the rapid formation of an unusual intermediate upon mixing tetracyclopropylethylene with 4-methyl-1,2,4-triazoline-3,5-dione in CDCl 3. Detailed characterization by NMR (proton, 13C, 2-D NMRs) indicates the intermediate is 5,5,6,6-tetracyclopropyl-3-methyl-5,6-dihydro-oxazolo[3,2- b][1,2,4]-triazolium-2-olate. Such products are extremely rare and have not been studied. Upon warming the intermediate is converted to 2 + 2 diazetidine (major) and ene product (minor). ^ To further explore the kinetics and dynamics of the reaction activation energies were obtained using Arrhenius plots. Activation energies for the formation of the intermediate from reactants, and 2+2 adduct from the intermediate were determined as 7.48 kcal moll and 19.8 kcal mol−1 with their pre-exponential values of 2.24 × 105 dm 3 mol−1 sec−1 and 2.75 × 108 sec−1, respectively, meaning net slow reactions because of low pre-exponential values caused by steric hindrance. ^

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The work on CERP monitoring item 3.1.3.5 (Marl prairie/slough gradients) is being conducted by Florida International University (Dr Michael Ross, Project Leader), with Everglades National Park (Dr. Craig Smith) providing administrative support and technical consultation. As of January 2006 the funds transferred by ACOE to ENP, and subsequently to FIU, have been entirely expended or encumbered in salaries or wages. The project work for 2005 started rather late in the fiscal year, but ultimately accomplished the Year 1 goals of securing a permit to conduct the research in Everglades National Park, finalizing a detailed scope of work, and sampling marsh sites which are most easily accessed during the wet season. 46 plots were sampled in detail, and a preliminary vegetation classification distinguished three groups among these sites (Sawgrass marsh, sawgrass and other, and slough) which may be arranged roughly along a hydrologic gradient from least to most persistently inundated . We also made coarser observations of vegetation type at 5-m intervals along 2 transects totaling ~ 5 km. When these data were compared with similar observations made in 1998-99, it appeared that vegetation in the western portion of Northeast Shark Slough (immediately east of the L-67 extension) had shifted toward a more hydric type during the last 6 years, while vegetation further east was unchanged in this respect. Because this classification and trend analysis is based on a small fraction of the data set that will be available after the first cycle of sampling (3 years from now), the results should not be interpreted too expansively. However, they do demonstrate the potential for gaining a more comprehensive view of marsh vegetation structure and dynamics in the Everglades, and will provide a sound basis for adaptive management.

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A new denuder-filter sampling technique has been used to investigate the gas/particle partitioning behaviour of the carbonyl products from the photooxidation of isoprene and 1,3,5-trimethylbenzene. A series of experiments was performed in two atmospheric simulation chambers at atmospheric pressure and ambient temperature in the presence of NOx and at a relative humidity of approximately 50%. The denuder and filter were both coated with the derivatizing agent O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine (PFBHA) to enable the efficient collection of gas- and particle-phase carbonyls respectively. The tubes and filters were extracted and carbonyls identified as their oxime derivatives by GC-MS. The carbonyl products identified in the experiments accounted for around 5% and 10% of the mass of secondary organic aerosol formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene respectively. Experimental gas/particle partitioning coefficients were determined for a wide range of carbonyl products formed from the photooxidation of isoprene and 1,3,5-trimethylbenzene and compared with the theoretical values based on standard absorptive partitioning theory. Photooxidation products with a single carbonyl moiety were not observed in the particle phase, but dicarbonyls, and in particular, glyoxal and methylglyoxal, exhibited gas/particle partitioning coefficients several orders of magnitude higher than expected theoretically. These findings support the importance of heterogeneous and particle-phase chemical reactions for SOA formation and growth during the atmospheric degradation of anthropogenic and biogenic hydrocarbons.

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Salty and warm Indian Ocean waters enter the South Atlantic via the Agulhas leakage, south of Africa. Model simulations and proxy evidence of Agulhas leakage strengthening during glacial terminations led to the hypothesis that it was an important modulator of the Atlantic Ocean circulation. Yet, the fate of the leakage salinity and temperature anomalies remains undocumented beyond the southern tip of Africa. Downstream of the leakage, new paleoceanographic evidence from the central Walvis Ridge (southeast Atlantic) shows that salinity increased at the thermocline, and less so at the surface, during glacial termination II. Thermocline salinity change coincided with higher frequency of Agulhas rings passage at the core location and with salinity maxima in the Agulhas leakage area, suggesting that leakage waters were incorporated in the Atlantic circulation through the thermocline. Hydrographic changes at the Walvis Ridge and in the leakage area display a distinct two-step structure, with a reversal at ca. 134 ka. This matched a wet interlude within the East Asia weak monsoon interval of termination II, and a short-lived North Atlantic warming. Such concurrence points to a Bølling-Allerød-like recovery of the Atlantic circulation amidst termination II, with a northward shift of the Intertropical Convergence Zone and Southern Hemisphere westerlies, and attendant curtailment of the interocean connection south of Africa.

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Background - Image blurring in Full Field Digital Mammography (FFDM) is reported to be a problem within many UK breast screening units resulting in significant proportion of technical repeats/recalls. Our study investigates monitors of differing pixel resolution, and whether there is a difference in blurring detection between a 2.3 MP technical review monitor and a 5MP standard reporting monitor. Methods - Simulation software was created to induce different magnitudes of blur on 20 artifact free FFDM screening images. 120 blurred and non-blurred images were randomized and displayed on the 2.3 and 5MP monitors; they were reviewed by 28 trained observers. Monitors were calibrated to the DICOM Grayscale Standard Display Function. T-test was used to determine whether significant differences exist in blurring detection between the monitors. Results - The blurring detection rate on the 2.3MP monitor for 0.2, 0.4, 0.6, 0.8 and 1 mm blur was 46, 59, 66, 77and 78% respectively; and on the 5MP monitor 44, 70, 83 , 96 and 98%. All the non-motion images were identified correctly. A statistical difference (p <0.01) in the blurring detection rate between the two monitors was demonstrated. Conclusions - Given the results of this study and knowing that monitors as low as 1 MP are used in clinical practice, we speculate that technical recall/repeat rates because of blurring could be reduced if higher resolution monitors are used for technical review at the time of imaging. Further work is needed to determine monitor minimum specification for visual blurring detection.