956 resultados para Ellberbe, L. W.


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We present the discovery of a wide (67 AU) substellar companion to the nearby (21 pc) young solar-metallicity M1 dwarf CD-35 2722, a member of the approximate to 100 Myr AB Doradus association. Two epochs of astrometry from the NICI Planet-Finding Campaign confirm that CD-35 2722 B is physically associated with the primary star. Near-IR spectra indicate a spectral type of L4 +/- 1 with a moderately low surface gravity, making it one of the coolest young companions found to date. The absorption lines and near-IR continuum shape of CD-35 2722 B agree especially well the dusty field L4.5 dwarf 2MASS J22244381-0158521, while the near-IR colors and absolute magnitudes match those of the 5 Myr old L4 planetary-mass companion, 1RXS J160929.1-210524 b. Overall, CD-35 2722 B appears to be an intermediate-age benchmark for L dwarfs, with a less peaked H-band continuum than the youngest objects and near-IR absorption lines comparable to field objects. We fit Ames-Dusty model atmospheres to the near-IR spectra and find T(eff) = 1700-1900 K and log(g) = 4.5 +/- 0.5. The spectra also show that the radial velocities of components A and B agree to within +/- 10 km s(-1), further confirming their physical association. Using the age and bolometric luminosity of CD-35 2722 B, we derive a mass of 31 +/- 8 M(Jup) from the Lyon/Dusty evolutionary models. Altogether, young late-M to mid-L type companions appear to be overluminous for their near-IR spectral type compared with field objects, in contrast to the underluminosity of young late-L and early-T dwarfs.

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Methylglyoxal is an a-oxoaldehyde putatively produced in excess from triose phosphates, aminoacetone, and acetone in some disorders, particularly in diabetes. Here, we investigate the nucleophilic addition of ONOO(-), known as a potent oxidant and nucleophile, to methylglyoxal, yielding an acetyl radical intermediate and ultimately formate and acetate ions. The rate of ONOO(-) decay in the presence of methylglyoxal [k(2,app) = (1.0 +/- 0.1) x 10(3) M(-1) s(-1); k(2) approximate to 1.0 x 10(5) M(-1) s(-1)] at pH 7.2 and 25 degrees C was found to be faster than that reported with monocarbonyl substrates (k(2) < 10(3) M(-1) diacetyl (k(2) = 1.0 x 10(4) M(-1) s(-1)), or CO(2) (k(2) = 3-6 x 10(4) M(-1) s(-1)). The pH profile of the methylglyoxal peroxynitrite reaction describes an ascendant curve with an inflection around pH 7.2, which roughly coincides with the pK(a) values of both ONOOH and H(2)PO(4)(-) ion. Electron paramagnetic resonance spin trapping experiments with 2-methyl-2-nitrosopropane revealed concentration-dependent formation of an adduct that can be attributed to 2-methyl-2-nitrosopropane-CH(3)CO(center dot) (a(N) = 0.83 mT). Spin trapping with 3,5-dibromo-4-nitrosobenzene sulfonate gave a signal that could be assigned to a methyl radical adduct [a(N) = 1.41 mT; a(H) = 1.35 mT; a(H(m)) = 0.08 mT]. The 2-methyl-2-nitrosopropane-CH(3)CO(center dot) adduct could also be observed by replacement of ONOO(-) with H(2)O(2), although at much lower yields. Acetyl radicals could be also trapped by added L-lysine as indicated by the presence of W-acetyl-L-lysine in the spent reaction mixture. This raises the hypothesis that ONOO(-)/H(2)O(2) in the presence of methylglyoxal is endowed with the potential to acetylate proteins in post-translational processes.

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Samverkan mellan företag, stat, kommuner, landsting o.s.v. och högskolor representerar tillsammans den plattform vilken ofta benämns som Triple Helix. Denna typ av samverkan utgår från antagandet att de inblandade aktörerna kan få bel&#246;ningar som överstiger de bidrag som de själva sätter in. En sådan samverkan antas också ge företag och den region de befinner sig i konkurrensfördelar och möjligheter att växa och utvecklas. Syftet med Wdalaprojektet, som startade våren 2005 och som skulle avslutas i och med utgången av 2006, var att bygga upp en sådan varaktig samverkan. Den frågan som är i fokus är hur framgångsrikt W-dalaprojektet varit i dessa avseenden? Den här studien försöker:a) beskriva hur projektet initierats och implementeratsb) värdera i vilken utsträckning projektets mål har uppnåtts samtc) identifiera och värdera funktionaliteten hos den samverkansmodellsom använtsErfarenheterna från projektet kan sammanfattas i sex punkter för vad som kan antas vara väsentligt för en l&#229;ngsiktig samverkan att fungera.1. Det behövs fora för kontinuerliga möten och en formaliserad organisation2. ”Kontaktpunkter” för att koordinera samarbetet spelar en viktig roll3. Högskolans ”leveransförmåga” måste förbättras4. ”Kulturkrockar” och en bristande ömsesidig tilltro5. Förmågan att definiera behov av samverkan behöver förbättras6. L&#229;ngsiktig hållbar ekonomi

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Projektet W-dala Plus - metodutveckling i samverkan mellan näringsliv och högskola är en fortsättning på det s.k. W-dalaprojektet (W-Dala – vinnande partnerskap mellan näringsliv och högskola) som startade våren 2005 och som, något försenat, avslutades under våren 2007. Syftet med det inledande projektet var att bygga upp en varaktig och innovativ samverkan mellan regionens näringsliv, den offentliga sektorns organisationer ochden högre utbildningen, för att skapa en ”triple helix-anda”. Sådan samverkan kan ske både formaliserat och genom att informella nätverk byggs upp. Denna samverkan avsågs att ”kunna bli självbärande genom att företagarna själva betalar för sitt behov av fortbildning och uppdragsforskning” (Projektplanen, W-Dala). Syftet var också att det arbete som inleddes skulle kunna öka företagens konkurrenskraft och därmed bidratill regional tillväxt.Syftet med studien är att belysa, tolka och analysera hur W-Dalaprojektet vidareutvecklats genom att projektet W-Dala Plus - metodutveckling i samverkan mellan näringsliv och högskola genomförts samt vilka erfarenheter som är möjliga att dra från detta. Resultatet kan i sin tur ge indikationer mot vilka områden fortsatta insatser kan vara l&#228;mpliga att riktas.

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The bodies of only two of 60,000 Australians who died in the Great War have been repatriated. The first - Sir W. l Bridges - is known; the other is unknown: the body of an unknown Australian soldier was returned in 1993 and entombed in the Australian War Memorial. The return of each offers insight into the ways in which the experience of death in the Great War was changing modes of grief and commemoration. While Bridges' return allowed public expression of private grief under new and terrible circumstances, an evolving culture of commemoration in the Great War made the public celebration of the one, known, man largely incompatible with the private grief of thousands.

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Bioactive brassinosteroids have been localized in developing and mature pollen of anhydrously fixed rye-grass (Lolium perenne) by immunocytochemistry using polyclonal antibodies to castasterone generated in rabbits. Tricellular pollen fixed by freeze-substitution was also labelled in the starch granules. Study of the developmental sequence of the pollen through the microsporocyte, microspore, bicellular and tricellular stages showed that the brassinosteroids were increasingly sequestered in starch granules as the amyloplasts matured, supporting the view that these are storage organelles for these potent plant growth promoters. In bicellular pollen, heavy labelling was seen in the zone within 0.5 μm of the starch granule, where stromal tissue remains. Thus, the stroma may be the site of synthesis of these compounds. During aqueous fixation, the brassinosteroids leached from the starch granules of tricellular pollen, indicating that they would be quickly available after imbibition to influence the physiology of germinating pollen. The results from high-performance liquid chromatography of dansylaminophenylboronates from partially purified extracts of freshly dehisced tricellular pollen of rye-grass showed 25-methylcastasterone may be a minor component, together with two unknown peaks. No specific binding of brassinolide to any soluble proteins extracted from tricellular rye-grass pollen was observed using the antibodies in gel electrophoresis or enzyme-linked immunosorbent assays.