970 resultados para 33-317_Site


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A study is made of the benthic foraminifers (size fraction > 63 µm) recovered from 59 upper Eocene through Quaternary sediment samples at DSDP Site 317 (Leg 33), located at a depth of 2598 m in the central part of the Manihiki Plateau (South Pacific). The sediments cored are disturbed in only two samples. The stratigraphic assignements used are based on previous studies of planktic foraminifers and other microfossils. In total, 216 taxa are identified. A cluster analysis based on the 77 species which comprised 5% or more of the entire foraminiferal assemblage in at least one sample suggests the presence of 3 major biostratigraphic zones corresponding approximately to the following ages, zone A: middle Miocene-Quaternary; zones B-C: early Miocene-Oligocene; and zone D: Eocene. The most important faunal turnover occurred between the Eocene and the Oligocene; a less pronounced break took place between the early and the middle Miocene, and an additional minor turnover between the Oligocene and the early Miocene. Eighteen taxa are long-ranging, being recorded from the middle Eocene through the Pliocene-Quaternary. It is concluded that, in general, benthic foraminifers of the bathyal zone are poor worldwide stratigraphic guide fossils; the following taxa are conditionally considered as the most suitable in the Eocene-Quaternary sequence: Aragonia aragonensis, Quadrimorphina profunda, Nuttallides truempyi, Abyssamina poagi, Buliminella grata, Bulimina jarvisi, B. macilenta, Turrilina alsatica, Cibicides notocenicus, C. wuellerstorfi, Pyrgo murrhina. However, most of these species are relatively rare.

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Radiolarian cherts in the Tethyan realm of Jurassic age were recently interpreted as resulting from high biosiliceous productivity along upwelling zones in subequatorial paleolatitudes the locations of which were confirmed by revised paleomagnetic estimates. However, the widespread occurrence of cherts in the Eocene suggests that cherts may not always be reliable proxies of latitude and upwelling zones. In a new survey of the global spatio-temporal distribution of Cenozoic cherts in Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) sediment cores, we found that cherts occur most frequently in the Paleocene and early Eocene, with a peak in occurrences at ~50 Ma that is coincident with the time of highest bottom water temperatures of the early Eocene climatic optimum (EECO) when the global ocean was presumably characterized by reduced upwelling efficiency and biosiliceous productivity. Cherts occur less commonly during the subsequent Eocene global cooling trend. Primary paleoclimatic factors rather than secondary diagenetic processes seem therefore to control chert formation. This timing of peak Eocene chert occurrence, which is supported by detailed stratigraphic correlations, contradicts currently accepted models that involve an initial loading of large amounts of dissolved silica from enhanced weathering and/or volcanism in a supposedly sluggish ocean of the EECO, followed during the subsequent middle Eocene global cooling by more vigorous oceanic circulation and consequent upwelling that made this silica reservoir available for enhanced biosilicification, with the formation of chert as a result of biosilica transformation during diagenesis. Instead, we suggest that basin-basin fractionation by deep-sea circulation could have raised the concentration of EECO dissolved silica especially in the North Atlantic, where an alternative mode of silica burial involving widespread direct precipitation and/or absorption of silica by clay minerals could have been operative in order to maintain balance between silica input and output during the upwelling-deficient conditions of the EECO. Cherts may therefore not always be proxies of biosiliceous productivity associated with latitudinally focused upwelling zones.

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A series of observational studies have been made to investigate the association of the ADAM33 gene polymorphisms with the risk of COPD, but their results were conflicting. Therefore, we performed an updated meta-analysis to quantitatively summarize the associations of ADAM33 gene polymorphisms with the risk of COPD. Thirteen case–control studies referring to nine SNPs were identified: V4 (rs2787094), T+1 (rs2280089), T2 (rs2280090), T1 (rs2280091), S2 (rs528557), S1 (rs3918396), Q−1 (rs612709), F+1 (rs511898) and ST+5 (rs597980). A dominant model (AA+Aa vs. aa), recessive model (AA vs. Aa+aa), additive model (AA vs. aa) and allelic model (A vs. a) were used to evaluate the association of ADAM33 polymorphism with the risk of COPD. The results indicated that significant associations were found for ADAM33 T1, T2, S1, Q−1, F+1 and ST+5 polymorphisms associated with the risk of COPD in different populations. However, no significant associations were found for V4, T+1 and S2 polymorphisms with the risk of COPD in all genetic models, even in the subgroup analysis by ethnicity. This meta-analysis provided evidence that the ADAM33 T1, T2, S1, Q−1, F+1 and ST+5 six locus polymorphisms association with the risk of COPD. Furthermore, T2, Q−1 and ST+5 indicated an association with the risk of COPD in the European populations, whereas T1, T2, S1, F+1 and Q−1 indicated an association with the risk of COPD in the Asian populations.

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The methylotrophic yeast Pichia pastoris is widely used for the production of recombinant glycoproteins. With the aim to generate biologically active 15N-labeled glycohormones for conformational studies focused on the unravelling of the NMR structures in solution, the P. pastoris strains GS115 and X-33 were explored for the expression of human chorionic gonadotropin (phCG) and human follicle-stimulating hormone (phFSH). In agreement with recent investigations on the N-glycosylation of phCG, produced in P. pastoris GS115, using ammonia/glycerol-methanol as nitrogen/carbon sources, the N-glycosylation pattern of phCG, synthesized using NH4Cl/glucose–glycerol–methanol, comprised neutral and charged, phosphorylated high-mannose-type N-glycans (Man8–15GlcNAc2). However, the changed culturing protocol led to much higher amounts of glycoprotein material, which is of importance for an economical realistic approach of the aimed NMR research. In the context of these studies, attention was also paid to the site specific N-glycosylation in phCG produced in P. pastoris GS115. In contrast to the rather simple N-glycosylation pattern of phCG expressed in the GS115 strain, phCG and phFSH expressed in the X-33 strain revealed, besides neutral high-mannose-type N-glycans, also high concentrations of neutral hypermannose-type N-glycans (Manup-to-30GlcNAc2). The latter finding made the X-33 strain not very suitable for generating 15N-labeled material. Therefore, 15N-phCG was expressed in the GS115 strain using the new optimized protocol. The 15N-enrichment was evaluated by 15N-HSQC NMR spectroscopy and GLC-EI/MS. Circular dichroism studies indicated that 15N-phCG/GS115 had the same folding as urinary hCG. Furthermore, 15N-phCG/GS115 was found to be similar to the unlabeled protein in every respect as judged by radioimmunoassay, radioreceptor assays, and in vitro bioassays.

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The aryloxy(alkoxy)cyclotriphosphazenes N3P3(OR)6�m(OC6H4Me-p)n(R = Me, n= 1�3; R = Et or CH2Ph, n= 3) rearrange on heating to give trioxocyclotriphosphazanes; the di- and mono-methoxy derivatives, N3P3(OMe)6�n(OC6H4Me-p)n(n= 4 or 5), yield dioxophosphaz-1-enes and an oxophosphazadiene respectively. The 1H, 13C and 31P NMR data for the starting materials and the products are presented. No evidence has been found for partially rearranged products. The geometrical disposition of the aryloxy groups in the starting material is retained in the rearranged products. Some aspects of the mechanism of the thermal rearrangement are discussed.

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Ukrainan presidentiksi nousi ns. oranssin vallankumouksen nosteessa Viktor Justsenko. Hänen presidenttikaudellaan (2005-2010) vuosien 1932-33 nälänhätä (holodomor) nousi keskeiseksi sekä sisä-, että ulkopolitiikan teemaksi. Holodomor, joka viittaa nälällä aiheutettuun tuhoon, pyrittiin tuomaan osaksi ukrainalaista kollektiivista muistia. Justsenkon aloitteesta säädettiin laki, jonka mukaan holodomor oli ukrainalaisten kansanmurha. Vuosina 1932-33 ympäri Neuvostoliittoa vallitsi nälänhätä. Ukrainalainen maaseutu kärsi pahoin nälänhädän seurauksista, sillä eri arvioiden mukaan 3,5-10 miljoonaa ukrainalaista menehtyi joko suoranaisesti tai välillisesti nälänhädän seurauksena. Ukrainan itsenäistyttyä nälänhätä, jota oli diasporassa alettu kutsua holodomoriksi (nälkätuho), nousi kansallisen historian keskeiseksi teemaksi. Ukrainalainen historioitsija Georgi Kasjanov on nimittänyt tätä uutta vaihetta historian kansallistamiseksi. Tässä työssä pohditaan sitä, miksi holodomor nostettiin keskeiseen asemaan presidentti Viktor Justsenkon valtakaudella. Keskeinen vastakkainasettelun lähtökohta on ollut itsenäisen Ukrainan ja Neuvostoliiton seuraajavaltion Venäjän suhtautuminen nälänhätään 1932-33. Ukrainalaisissa näkökulmissa on painottunut stalinistisen järjestelmän kritiikki, mikä toisaalta on saatettu tulkita myös koko kommunistisen aikakauden tuomitsemiseksi. Venäjällä taas nälänhätä on tulkittu useimmiten yleisneuvostoliittolaiseksi tragediaksi, joka ei kohdistunut erityisesti mitään tiettyä kansallisuutta vastaan. Tutkimuksen keskeinen lähtökohta on tarkastella ukrainalaisten ja venäläisten tulkintojen eroja ja sitä, millä tavoin holodomorilla on tehty politiikkaa. Tutkimusaineistona on käytetty ukrainalaisten osalta presidentti Justsenkon puheita, lakialoitteita ja muita julkilausumia, sekä eräiden yhteiskunnallisten toimijoiden ja historioitsijoiden kannanottoja. Venäläisen osapuolen tulkintoja on pyritty luomaan muutamien tutkimusten ja yhteiskunnallisten toimijoiden, sekä poliitikkojen lausumien pohjalta. Suurin osa aineistosta on kerätty venäjänkielisistä verkkolehdistä. Presidentti Justsenkolle vuosien 1932-1933 historiasta muodostui ase, jolla hän kävi omaa poliittista taisteluaan lännen puolesta itää vastaan. Välit Venäjään olivat viileät koko hänen presidenttikautensa ajan. Lähimmäksi presidentin kantaa holodomor-kysymyksessä tulivat diasporaukrainalaiset. Venäjällä kritisoitiin ankarasti Justsenkon tanssia haudoilla eli hänen tapaansa käyttää nälänhädän uhreja oman politiikkansa välineenä. Venäläiset korostivat nälänhädän tragediaa kaikkien Neuvostoliiton kansojen tragediana. Holodomor oli osa kansallisen historian uudelleenkirjoitusta ja kansakunnan rakentamisen prosessia. Justsenkon päämääränä oli lähentää Ukrainaa länteen, jolloin ukrainalaisen kansakunnan uhriasema antoi oikeutuksen sanoutua irti neuvostoajasta. Tietyssä mielessä holodomor-projekti oli venäläisvastainen, sillä se implisiittisesti tuki käsitystä venäläisistä rikollisina, kansanmurhan toimeenpanijoina.

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Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) and Ce(0.67)Fe(0.33)O(2-delta) have been synthesized by a new low temperature sonochemical method using diethylenetriamine as a complexing agent. Due to the substitution of Fe and Pt ions in CeO(2), lattice oxygen is activated in Ce(0.67)Fe(0.33)O(2-delta) and Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta). Hydrogen uptake studies show strong reduction peaks at 125 C in Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) against a hydrogen uptake peak at 420 degrees C in Ce(0.67)Fe(0.33)O(2-delta). Fe substituted ceria, Ce(0.67)Fe(0.33)O(2-delta) itself acts as a catalyst for CO oxidation and water gas shift (WGS) reactions at moderate temperatures. The rate of CO conversion in WGS with Pt free Ce(0.65)Fe(0.33)O(2-delta) is 2.8 mu mol g(-1) s(-1) at 450 C and with Pt substituted Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta) is 4.05 mu mol g(-1) s(-1) at 275 degrees C. Due to the synergistic interaction of the Pt ion with Ce and Fe ions in Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta), the catalyst showed much higher activity for CO oxidation and WGS reactions compared to Ce(0.67)Fe(0.33)O(2-delta). A reverse WGS reaction does not occur over Ce(0.65)Fe(0.33)Pt(0.02)O(2-delta). The catalyst also does not deactivate even when operated for a long time. Nearly 100% conversion of CO to CO(2) with 100% H(2) selectivity is observed in WGS reactions even up to 550 degrees C. (C) 2011 Elsevier B.V. All rights reserved.

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A comparative morphological study of different ZnO nanostructures was carried out with different varying process parameters for energy harvesting. Molarity, temperature, growth duration and seed layer were such fundamental controlling parameters. The study brings out an outstanding piezoelectric coefficient (d(33)) of 44.33 pm/V for vertically aligned ZnO nanorod structures, considered as the highest reported d(33) value for any kind of ZnO nanostructures. XRD analysis confirms wurtzite nature of this nanorod structure with 0001] as preferential growth direction. Semiconducting characteristic of nanorods was determined with temperature induced I/V characterization.

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Contenido: Elementos para una definición del Derecho Internacional Privado / Raúl Alberto Ramayo – Elementos para determinar la jurisdicción ius privatista internacional / Raúl Alberto Ramayo – Mediación : elabore y decida su propia solución / Zulema Wilde – Contratos informáticos en la Argentina / Pablo Andrés Palazzi – El honor y la censura : ¿una contradicción? / Flavio F. Agatiello Piñero – La filosofía del derecho de Hegel y el catolicismo / Ignacio Andereggen – El arte político de los cristianos para la construcción de la ciudad del hombre / Franco Biffi – Servio Tulio, rey censor / Alfredo Grieco y Bavio – Una cuestión filosófica en el quinto centenario : ¿fue legítimo el imperio hispánico en América? / Héctor H. Hernández

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Analisa questões sobre a judicialização dos conflitos e o ativismo judicial, bem como aspectos referentes à Proposta de Emenda Constitucional (PEC 33/2011) que visa alterar dispositivos do texto magno a fim de aumentar ou criar o controle do Legislativo sobre algumas das decisões do Supremo Tribunal Federal.

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Report/South Africa- Recasting the Net, What’s New, Webby?- European Parliament resolution recognizes women in fisheries,America/Canada- Stuck at the back of the boat, Milestones- Magna Carta of Women adopted in Philippines, Profile- Chitra Suriyakumar: Living in Hope, Report/India- Women, the Eyes of the World, Q&A- Interview with Clarisse Canha from Associação para a Igualdade e Direitos das Mulheres —Association for Equality and Rights for Women (UMAR-Azores), Yemaya Mama- ... sums it up !! Yemaya Recommends- Fisherwomen, Fishermen’s Wives.