878 resultados para RU(BPY)(3)(3 )-BASED CHEMILUMINESCENCE DETECTION


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The herbicide propanil has long been used in rice production in southern Brazil. Bacteria isolated from contaminated soils in Massaranduba, Santa Catarina, Brazil, were found to be able to grow in the presence of propanil, using this compound as a carbon source. Thirty strains were identified as Pseudomonas (86.7%), Serratia (10.0%), and Acinetobacter (3.3%), based on phylogenetic analysis of 16S rDNA. Little genetic diversity was found within species, more than 95% homology, suggesting that there is selective pressure to metabolize propanil in the microbial community. Two strains of Pseudomonas (AF7 and AF1) were selected in bioreactor containing chemotactic growth medium, with the highest degradation activity of propanil exhibited by strain AF7, followed by AF1 (60 and 40%, respectively). These strains when encapsulated in alginate exhibited a high survival rate and were able to colonize the rice root surfaces. Inoculation with Pseudomonas strains AF7 and AF1 significantly improved the plant height of rice. Most of the Pseudomonas strains produced indoleacetic acid, soluble mineral phosphate, and fixed nitrogen. These bacterial strains could potentially be used for the bioremediation of propanil-contaminated soils and the promotion of plant growth.

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This work presents two potential metallo-drugs, the ionic (C17H19FN3O3)(3)[RuCl6]center dot 3H(2)O (1) and the coordination [Ru(C17H17FN3O3)(3)]center dot 4H(2)O (2) compounds, obtained by the combination of ruthenium(III) and ciprofloxacin in different synthetic conditions. The ESI MS spectrum of 1 displayed a main peak at m/z = 994.6, assigned to the gaseous phase adduct (ciprofloxacin)(3)center dot H+, while 2 featured peaks at m/z 1093.3 and 547.1 ascribed to [Ru(C17H17FN3O3)(3)center dot H+-4H(2)O](+) and [Ru(C17H17FN3O3)(3)center dot 2H(+)-4H(2)O](2+). Thermal analysis corroborated the proposed water content for both complexes. Absorption spectra of the compounds in aqueous medium are dominated by ciprofloxacin transitions in the UV region but displayed weak bands in the visible region, assigned to ligand field transitions. The cyclic voltammograms of 2 exhibited a quasi-reversible process ascribed to the Ru(II)/(III) redox pair at -0.25V (vs. SHE) while 1 displayed this process at -0.11 V, showing that the central ruthenium ion is stabilized in the (III) oxidation state by the coordination to the hard oxygen atoms of ciprofloxacin. The solubility of 1 is pH dependent (as well as free ciprofloxacin) while 2 is fully water soluble and stable under physiological pH for at least 48 h. The compounds are also stable under incubation conditions (stomach pH and 37 degrees C) without significant pH lowering. An interaction study of 2 with ct-DNA showed a value of K-b = 2.47 (+/- 0.89) x 10(4) mol(-1) L for the intrinsic binding constant.

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Obiettivo del mio lavoro di tesi è stato quello di verificare la fattibilità di un nuovo processo per la produzione di acido adipico da cicloesene con due stadi di reazione. Il primo stadio di reazione prevede l’ossidazione del cicloesene con soluzione acquosa di acqua ossigenata a formare l’epossido, che idrata a 1,2-cicloesandiolo, mentre nel secondo stadio il glicole viene ossidato con ossigeno ad acido adipico. Il lavoro è stato focalizzato sullo studio del meccanismo di reazione per l’ossidazione del 1,2-cicloesandiolo ad acido adipico, utilizzando catalizzatori a base di Ru(OH)3/Al2O3, Ru(OH)3-Bi(OH)3/Al2O3, Cu/C e Cu/TiO2. Le prove condotte hanno dimostrato che i catalizzatori usati sono attivi nell’ossidazione di 1,2-cicloesandiolo, ma sono caratterizzati da scarsa selettività ad acido adipico. Dall’analisi dei risultati ottenuti si desume che la reazione richiede condizioni fortemente basiche per potere avvenire. In queste condizioni però si vengono a formare degli intermedi che reagiscono rapidamente con l’acqua e con l’ossigeno, dando luogo alla formazione di una serie di prodotti primari e secondari.

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Das Wolf-Hirschhorn-Syndrom (WHS) ist ein komplexes und variables Fehlbildungs- Retardierungssyndrom, das durch Deletion in der distalen Chromosomenregion 4p16.3 hervorgerufen wird und dessen Ätiologie und Pathogenese bisher weitgehend unverstanden sind. Die Zielsetzung in der vorliegenden Arbeit bestand in der Identifizierung und vorläufigen Charakterisierung neuer Gene, die an der Entstehung des Syndroms beteiligt sein könnten. Die Wolf-Hirschhorn-Syndrom-kritische Region (WHSCR) konnte zu Beginn der vorliegenden Arbeit auf einen ca. 2 Mb großen Bereich zwischen den Markern D4S43 und D4S142 eingegrenzt werden. Für die Identifizierung neuer Gene wurden zunächst drei größere genomische Cosmid-/PAC-Contigs (I-III) im Bereich der Marker D4S114 bis D4S142 erstellt und mittels Exonamplifikation auf transkribierte Bereiche (Exons) untersucht. Es konnten insgesamt 67 putative 'Exons' isoliert werden, von denen einige bereits bekannten Genen (ZNF141, PDEB, MYL5, GAK, DAGK4 und FGFR3) entsprechen. Zwei dieser Gene konnten im Rahmen dieser Arbeit erstmals (DAGK4) bzw. genauer (GAK) in die distale Region 4p16.3 kartiert werden. Die restlichen Exons können aufgrund von Homologievergleichen und/oder EST-cDNA-Homologien vermutlich neuen Genen oder auch Pseudogenen (z. B. YWEE1hu) zugeordnet werden. Durch die im Verlaufe der vorliegenden Arbeit publizierte weitere Eingrenzung der WHSCR auf einen 165 Kb-großen Bereich proximal des FGFR3-Gens konzentrierten sich weitere Untersuchungen auf die detaillierte Analyse der WHSCR zwischen dem Marker D4S43 und FGFR3. Mit Hilfe von Exonamplifikation bzw. computergestützter Auswertung vorliegender Sequenzdaten aus diesem Bereich ('GRAIL', 'GENSCAN' und Homologievergleiche in den EST-Datenbanken des NCBI) konnten mehrere neue Gene identifiziert werden. In distaler-proximaler Reihenfolge handelt es sich dabei um die Gene LETM1, 51, 43, 45, 57 und POL4P. LETM1 kodiert für ein putatives Transmembran-Protein mit einem Leucin-Zipper- und zwei EF-Hand-Motiven und könnte aufgrund seiner möglichen Beteiligung an der Ca2+-Homeostase und/oder der Signal-transduktion zu Merkmalen des WHS (Krampfanfällen, mentale Retardierung und muskuläre Hypotonie) beitragen. Das Gen 51 entspricht einem in etwa zeitgleich durch Stec et al. (1998) und Chesi et al. (1998) als WHSC1 bzw. MMSET bezeichnetem Gen und wurde daher nicht weiter charakterisiert. Es wird genauso wie das Gen 43, das zeitgleich von Wright et al. (1999b) als WHSC2 beschrieben werden konnte und eine mögliche Rolle bei der Transkriptionselongation spielt, ubiquitär exprimiert. Das in der vorliegenden Arbeit identifizierte Gen 45 zeigt demgegenüber ein ausgesprochen spezifisches Expressionsmuster (in Nervenzellen des Gehirns sowie in Spermatiden). Dies stellt zusammen mit der strukturellen Ähnlichkeit des putativen Genprodukts zu Signalmolekülen einen interessanten Zusammenhang zu Merkmalen des WHS (beispielsweise Kryptorchismus, Uterusfehlbildungen oder auch neurologische Defekte) her. Demgegenüber handelt es sich bei dem Gen 57 möglicherweise um ein trunkiertes Pseudogen des eRFS-Gens auf Chromosom 6q24 (Wallrapp et al., 1998). Das POL4P-Gen schließlich stellt allein aufgrund seiner genomischen Lokalisation sowie seiner möglichen Funktion (als DNA-Polymerase-ähnliches Gen) kein gutes Kandidatengen für spezifische Merkmale des Syndroms dar und wurde daher nicht im Detail charakterisiert. Um die Beteiligung der Gene an der Ätiologie und Pathogenese des Syndroms zu verstehen, ist die Entwicklung eines Mausmodells (über das Einfügen gezielter Deletionen in das Mausgenom) geplant. Um dies zu ermöglichen, wurde in der vorliegenden Arbeit die Charakterisierung der orthologen Region bei der Maus vorgenommen. Zunächst wurden die orthologen Gene der Maus (Letm1, Whsc1, Gen 43 (Whsc2h), Gen 45 und Pol4p) identifiziert. Durch die Erstellung sowie die genaue Kartierung eines murinen genomischen P1/PAC-Klon-Contigs konnte gezeigt werden, daß die murinen Gene Fgfr3, Letm1, Whsc1, Gen 43 (Whsc2h), Gen 45 und Pol4p sowie einige weitere der überprüften EST-cDNA-Klone der Maus in einem durchgehenden Syntänieblock zwischen Mensch (POL4P bis FGFR3) und Maus (Mmu 5.20) enthalten sind, der in seiner genomischen Ausdehnung in etwa den Verhältnissen beim Menschen (zwischen POL4P und FGFR3) entspricht.

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ABSTRACTDie vorliegende Arbeit befasste sich mit der Reinigung,heterologen Expression, Charakterisierung, molekularenAnalyse, Mutation und Kristallisation des EnzymsVinorin-Synthase. Das Enzym spielt eine wichtige Rolle inder Ajmalin-Biosynthese, da es in einerAcetyl-CoA-abhängigen Reaktion die Umwandlung desSarpagan-Alkaloids 16-epi-Vellosimin zu Vinorin unterBildung des Ajmalan-Grundgerüstes katalysiert. Nach der Reinigung der Vinorin-Synthase ausHybrid-Zellkulturen von Rauvolfia serpentina/Rhazya strictamit den fünf chromatographischen TrennmethodenAnionenaustauschchromatographie an SOURCE 30Q, HydrophobeInteraktionen Chromatographie an SOURCE 15PHE,Chromatographie an MacroPrep Ceramic Hydroxyapatit,Anionenaustauschchromatographie an Mono Q undGrößenausschlußchromatographie an Superdex 75 konnte dieVinorin-Synthase aus 2 kg Zellkulturgewebe 991fachangereichert werden.Das nach der Reinigung angefertigte SDS-Gel ermöglichte eineklare Zuordnung der Protein-Bande als Vinorin-Synthase.Der Verdau der Enzymbande mit der Endoproteinase LysC unddie darauffolgende Sequenzierung der Spaltpeptide führte zuvier Peptidsequenzen. Der Datenbankvergleich (SwissProt)zeigte keinerlei Homologien zu Sequenzen bekannterPflanzenenzyme. Mit degenerierten Primern, abgeleitet voneinem der erhaltenen Peptidfragmente und einer konserviertenRegion bekannter Acetyltransferasen gelang es, ein erstescDNA-Fragment der Vinorin-Synthase zu amplifizieren. Mit derMethode der RACE-PCR wurde die Nukleoidsequenzvervollständigt, was zu einem cDNA-Vollängenklon mit einerGröße von 1263 bp führte, der für ein Protein mit 421Aminosäuren (46 kDa) codiert.Das Vinorin-Synthase-Gen wurde in den pQE2-Expressionsvektorligiert, der für einen N-terminalen 6-fachen His-tagcodiert. Anschließend wurde sie erstmals erfolgreich in E.coli im mg-Maßstab exprimiert und bis zur Homogenitätgereinigt. Durch die erfolgreiche Überexpression konnte dieVinorin-Synthase eingehend charakterisiert werden. DerKM-Wert für das Substrat Gardneral wurde mit 20 µM, bzw.41.2 µM bestimmt und Vmax betrug 1 pkat, bzw. 1.71 pkat.Nach erfolgreicher Abspaltung des His-tags wurden diekinetischen Parameter erneut bestimmt (KM- Wert 7.5 µM, bzw.27.52 µM, Vmax 0.7 pkat, bzw. 1.21 pkat). Das Co-Substratzeigt einen KM- Wert von 60.5 µM (Vmax 0.6 pkat). DieVinorin-Synthase besitzt ein Temperatur-Optimum von 35 °Cund ein pH-Optimum bei 7.8.Homologievergleiche mit anderen Enzymen zeigten, dass dieVinorin-Synthase zu einer noch kleinen Familie von bisher 10Acetyltransferasen gehört. Alle Enzyme der Familie haben einHxxxD und ein DFGWG-Motiv zu 100 % konserviert. Basierendauf diesen Homologievergleichen und Inhibitorstudien wurden11 in dieser Proteinfamilie konservierte Aminosäuren gegenAlanin ausgetauscht, um so die Aminosäuren einer in derLiteratur postulierten katalytischen Triade(Ser/Cys-His-Asp) zu identifizieren.Die Mutation aller vorhandenen konservierten Serine undCysteine resultierte in keiner Mutante, die zumvollständigen Aktivitätsverlust des Enzyms führte. Nur dieMutationen H160A und D164A resultierten in einemvollständigen Aktivitätsverlust des Enzyms. Dieses Ergebniswiderlegt die Theorie einer katalytischen Triade und zeigte,dass die Aminosäuren H160A und D164A exklusiv an derkatalytischen Reaktion beteiligt sind.Zur Überprüfung dieser Ergebnisse und zur vollständigenAufklärung des Reaktionsmechanismus wurde dieVinorin-Synthase kristallisiert. Die bis jetzt erhaltenenKristalle (Kristallgröße in µm x: 150, y: 200, z: 200)gehören der Raumgruppe P212121 (orthorhombisch primitiv) anund beugen bis 3.3 Å. Da es bis jetzt keine Kristallstruktureines zur Vinorin-Synthase homologen Proteins gibt, konntedie Struktur noch nicht vollständig aufgeklärt werden. ZurLösung des Phasenproblems wird mit der Methode der multiplenanomalen Dispersion (MAD) jetzt versucht, die ersteKristallstruktur in dieser Enzymfamilie aufzuklären.

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This research based on 3 indipendent studies, sought to explore the nature of the relationship between overweight/obesity, eating behaviors and psychological distress; the construct of Mindful eating trough the validation of the Italian adaptation of the Mindful Eating Questionnaire (MEQ); the role of mindfulnessand mindful eating as respectively potential mediator and moderator between overeating behavior (binge eating and emotional overeating) and negative outcomes (psychological distress, body dissatisfaction). All the samples were divided in normal weight, overweight and obese according to BMI categories. STUDY1: In a sample of 691 subjects (69.6% female, mean aged 39.26 years) was found that BMI was not associated with psychological distress, whereas binge eating increases the psychopathological level. BMI and male gender represent negative predictors of psychological distress, but certain types of overeating (i.e., NES/grazing, overeating during or out of meals, and guilt/restraint) result as positive predictors.. STUDY 2 : A sample of 1067 subjects (61.4% female, mean aged 34 years) was analized. The Italian MEQ resulted in a 26-item 4-factor model measuring Disinhibition, Awareness, Distraction, and Emotional response. Internal consistency and test-retest reliability were acceptable MEQ correlated positively with mindfulness (FMI) and it was associated with sociodemographic variables, BMI, meditation. type of exercise and diet. STUDY 3, based on a sample of 502 subjects (68.8% female, mean aged 39.42 years) showed that MEQ and FMI negatively correlated with BES, EOQ, SCL-90-R, and BIAQ. Obese people showed lower level of mindful eating and higher levels of binge eating, emotional overeating, and body dissatisfaction, compared to the other groups Mindfulness resulted to partially mediates the relationship between a) binge eating and psychological distress, b) emotional overeating and psychological distress, c) binge eating and mental well-being, d) emotional overeating and menal well-being. Mindful eating was a moderator only in the relationship between emotional overeating and body dissatisfaction.

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Exogenous melatonin is widely used for sleep disorders and has potential value in neuroprotection, cardioprotection and as an antioxidant. Here, a novel method is described for the determination of melatonin and six metabolites in mouse urine by use of LC-MS/MS and GC-MS. LC-MS/MS is used for the measurement of melatonin, N1-acetyl-5-methoxykynuramine (AMK), N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) and 6-hydroxymelatonin (6-HMEL), while GC/MS is used for the determination of N-[2-(5-methoxy-2-oxo-2,3-dihydro-1H-indol-3-yl)-ethyl]-acetamide (2-OMEL) and cyclic 3-hydroxymelatonin (3-HMEL) with detection limits on column of 0.02-0.5 pmol, depending on the metabolite. Following oral administration of melatonin to mice, a 0-24 hr urine collection revealed the presence of melatonin (0.2% dose), 6-HMEL (37.1%) and NAS (3.1%) comprising >90% of the total metabolites; AMK and AFMK were also detected at 0.01% each; 2-OMEL was found at 2.2% of the dose, which is >100 times more than the AMK/AFMK pathway, and comprises >5% of the melatonin-related material detected in mouse urine. 3-HMEL was largely found as a sulfate conjugate. These studies establish sensitive assays for determination of six melatonin metabolites in mouse urine and confirm the potential for antioxidant activity of melatonin through the identification in vivo of AMK and AFMK, ring-opened metabolites with a high capacity for scavenging reactive oxygen species.

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The patterning of photoactive purple membrane (PM) films onto electronic substrates to create a biologically based light detection device was investigated. This research is part of a larger collaborative effort to develop a miniaturized toxin detection platform. This platform will utilize PM films containing the photoactive protein bacteriorhodopsin to convert light energy to electrical energy. Following an effort to pattern PM films using focused ion beam machining, the photolithography based bacteriorhodopsin patterning technique (PBBPT) was developed. This technique utilizes conventional photolithography techniques to pattern oriented PM films onto flat substrates. After the basic patterning process was developed, studies were conducted that confirmed the photoelectric functionality of the PM films after patterning. Several process variables were studied and optimized in order to increase the pattern quality of the PM films. Optical microscopy, scanning electron microscopy, and interferometric microscopy were used to evaluate the PM films produced by the patterning technique. Patterned PM films with lateral dimensions of 15 μm have been demonstrated using this technique. Unlike other patterning techniques, the PBBPT uses standard photolithographic processes that make its integration with conventional semiconductor fabrication feasible. The final effort of this research involved integrating PM films patterned using the PBBPT with PMOS transistors. An indirect integration of PM films with PMOS transistors was successfully demonstrated. This indirect integration used the voltage produced by a patterned PM film under light exposure to modulate the gate of a PMOS transistor, activating the transistor. Following this success, a study investigating how this PM based light detection system responded to variations in light intensity supplied to the PM film. This work provides a successful proof of concept for a portion of the toxin detection platform currently under development.

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OBJECTIVE: The purpose of this study was to evaluate, in relation to intraoperative estimated blood loss (EBL), the effectiveness of preoperative transcatheter arterial embolization of hypervascular osseous metastatic lesions before orthopedic resection and stabilization. MATERIALS AND METHODS: Between June 1987 and November 2007, 22 patients underwent transcatheter arterial embolization of tumors of the long bone, hip, or vertebrae before resection and stabilization. Osseous metastatic lesions from renal cell carcinoma, malignant melanoma, leiomyosarcoma, and prostate cancer were embolized. All patients were treated with a coaxial catheter technique with polyvinyl alcohol (PVA) particles alone or a combination of PVA particles and coils. After embolization, each tumor was angiographically graded according to devascularization (grades 1-3) based on tumor blush after contrast injection into the main tumor-feeding arteries. RESULTS: In patients with complete devascularization (grade 1), mean EBL was calculated to be 1,119 mL, whereas in patients with partial embolization (grades 2 and 3) EBL was 1,788 mL and 2,500 mL. With respect to intraoperative EBL, no significant difference between devascularization grades was found (p > 0.05). Moderate correlation (r = 0.51, p = 0.019) was observed between intraoperative EBL and tumor size before embolization. Only low correlation (r = 0.44, p = 0.046) was found between intraoperative EBL and operating time. Major complications included transient palsy of the sciatic nerve and gluteal abscess in one patient. CONCLUSION: The results of this study support the concept that there is no statistically significant difference among amounts of intraoperative EBL with varying degrees of embolization.

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A marked increase in canine leptospirosis was observed in Switzerland over 10 years with a peak incidence of 28.1 diagnosed cases/100,000 dogs/year in the most affected canton. With 95% affected dogs living at altitudes <800 m, the disease presented a seasonal pattern associated with temperature (r2 0.73) and rainfall (r2 0.39), >90% cases being diagnosed between May and October. The increasing yearly incidence however was only weakly correlated with climatic data including number of summer (r2 0.25) or rainy days (r2 0.38). Serovars Australis and Bratislava showed the highest seropositivity rates with 70.5% and 69.1%, respectively. Main clinical manifestations included renal (99.6%), pulmonary (76.7%), hepatic (26.0%), and hemorrhagic syndromes (18.2%), leading to a high mortality rate (43.3%). Similar to the human disease, liver involvement had the strongest association with negative outcome (OR 16.3). Based on these data, canine leptospirosis presents similar features and severity as the human infection for which it therefore can be considered a model. Its re-emergence in a temperate country with very high incidence rates in canines should thus be viewed as a warning and emphasize the need for increased awareness in other species.

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AIMS Children conceived by assisted reproductive technology (ART) display vascular dysfunction. Its underlying mechanism, potential reversibility and long-term consequences for cardiovascular risk are unknown. In mice, ART induces arterial hypertension and shortens the life span. These problems are related to decreased vascular endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) synthesis. The aim of this study was to determine whether ART-induced vascular dysfunction in humans is related to a similar mechanism and potentially reversible. To this end we tested whether antioxidants improve endothelial function by scavenging free radicals and increasing NO bioavailability. METHODS AND RESULTS In this prospective double-blind placebo controlled study in 21 ART and 21 control children we assessed the effects of a four-week oral supplementation with antioxidant vitamins C (1 g) and E (400 IU) or placebo (allocation ratio 2:1) on flow-mediated vasodilation (FMD) of the brachial artery and pulmonary artery pressure (echocardiography) during high-altitude exposure (3454 m), a manoeuver known to facilitate the detection of pulmonary vascular dysfunction and to decrease NO bioavailability by stimulating oxidative stress. Antioxidant supplementation significantly increased plasma NO measured by ozone-based chemiluminescence (from 21.7 ± 7.9 to 26.9 ± 7.6 µM, p = 0.04) and FMD (from 7.0 ± 2.1 to 8.7 ± 2.0%, p = 0.004) and attenuated altitude-induced pulmonary hypertension (from 33 ± 8 to 28 ± 6 mm Hg, p = 0.028) in ART children, whereas it had no detectable effect in control children. CONCLUSIONS Antioxidant administration to ART children improved NO bioavailability and vascular responsiveness in the systemic and pulmonary circulation. Collectively, these findings indicate that in young individuals ART-induced vascular dysfunction is subject to redox regulation and reversible.

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High-resolution records of opal, carbonate, and terrigenous fluxes have been obtained from a high-sedimentation rate core (MD84-527: 43°50'S; 51°19'E; 3269 m) by normalization to 230Th. This method estimates paleofluxes to the seafloor on a point-by-point basis and distinguishes changes in sediment accumulation due to variations in vertical rain rates from those due to changes in syndepositional sediment redistribution by bottom currents. We also measured sediment delta15N to evaluate the changes in nitrate utilization in the overlying surface waters associated with paleoflux variations. Our results show that opal accumulation rates on the seafloor during the Holocene and stage 3, based on 14C dating, were respectively tenfold and fivefold higher than the vertical rain rates, At this particular location, changes in opal accumulation on the seafloor appear to be mainly controlled by sediment redistribution by bottom currents rather than variations in opal fluxes from the overlying water column. Correction for syndepositional sediment redistribution and the improved time resolution that can be achieved by normalization to 230Th disclose important variations in opal rain rates. We found relatively high but variable opal paleoflux during stage 3, with two maxima centered at 36 and 30 kyr B.P., low opal paleoflux during stage 2 and deglaciation and a pronounced maximum during the early Holocene, We interpret this record as reflecting variations in opal production rates associated with climate-induced latitudinal migration of the southern ocean frontal system. Sediments deposited during periods of high opal paleoflux also have high authigenic U concentrations, suggesting more reducing conditions in the sediment, and high Pa-231/Th-230 ratios, suggesting increased scavenging from the water column. Sediment delta15N is circa 1.5 per mil higher during isotopic stage 2 and deglaciation. The low opal rain rates recorded during that period appear to have been associated with increased nitrate depletion. This suggests that opal paleofluxes do not simply reflect latitudinal migration of the frontal system but also changes in the structure of the upper water column. Increased stratification during isotopic stage 2 and deglaciation could have been produced by a meltwater lid, leading to lower nitrate supply rates to surface waters.

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The (231Pa/230Th)xs,0 records obtained from two cores from the western (MD97-2138; 1°25'S, 146°24'E, 1900 m) and eastern (ODP Leg 138 Site 849, 0°11.59'N, 110°31.18'W, 3851 m) equatorial Pacific display similar variability over the last 85000 years, i.e. from isotopic stages 1 to 5a, with systematically higher values during the Holocene, isotopic stage 3 and isotopic stage 5a, and lower values, approaching the production rate ratio of the two isotopes (0.093), during the colder periods corresponding to isotopic stages 2 and 4. We have also measured the 230Th-normalized biogenic preserved and terrigenous fluxes, as well as major and trace elements concentrations, in both cores. The (231Pa/230Th)xs,0 results combined with the changes in preserved carbonate and opal fluxes at the eastern site indicate lower productivity in the eastern equatorial Pacific during glacial periods. The (231Pa/230Th)xs,0 variations in the western equatorial Pacific (WEP) also seem to be controlled by productivity (carbonate and/or opal). The generally high (231Pa/230Th)xs,0 ratios (>0.093) of the profile could be due to opal and/or MnO2 in the sinking particles. The profiles of (231Pa/230Th)xs,0 and 230Th-normalized fluxes indicate a decrease in exported carbonate, and possibly opal, during isotopic stages 2 and 4 in MD97-2138. Using 230Th-normalized flux, we also show that sediments from the two cores were strongly affected by sediment redistribution by bottom currents suggesting a control of mass accumulation rates by sediment focusing variability.

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Marine biological productivity has been invoked as a possible climate driver during the early Paleogene through its potential influence on atmospheric carbon dioxide concentrations. However, the relationship of export productivity (the flux of organic carbon (C) from the surface ocean to the deep ocean) to organic C burial flux (the flux of organic C from the deep ocean that is buried in marine sediments) is not well understood. We examine the various components involved with atmosphere-to-ocean C transfer by reconstructing early Paleogene carbonate and silica production (using carbonate and silica mass accumulation rates (MARs)); export productivity (using biogenic barium (bio-Ba) MARs); organic C burial flux (using reactive phosphorus (P) MARs); redox conditions (using uranium and manganese contents); and the fraction of organic C buried relative to export productivity (using reactive P to bio-Ba ratios). Our investigations concentrate on Paleocene/Eocene sections of Sites 689/690 from Maud Rise and Site 738 from Kerguelen Plateau. In both regions, export productivity, organic C burial flux, and the fraction of organic C buried relative to export productivity decreased from the Paleocene/early Eocene to the middle Eocene. A shift is indicated from an early Paleogene two-gyre circulation in which nutrients were not efficiently recycled to the surface via upwelling in these regions, to a circulation more like the present day with efficient recycling of nutrients to the surface ocean. Export productivity was enhanced for Kerguelen Plateau relative to Maud Rise throughout the early Paleogene, possibly due to internal waves generated by the plateau regardless of gyre circulation.

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La historia de la arquitectura se ha medido - en parte - por la evolución de las modas, épocas y estilos de la arquitectura religiosa. En la aparición de las nuevas capillas interreligiosas universitarias de los años '50 de Norteamérica, la capilla del M.I.T., bautizada tras su inauguración como “Kresge Chapel” en honor al apellido de su benefactor, fue el máximo exponente como prototipo en esta época marcada por la aparición nuevas conciencias de posguerra. (II Guerra Mundial). La tesis centra su investigación en esta capilla, cómo nació en respuesta a la necesidad de compatibilizar la enseñanza reglada científico tecnológica con una formación religiosa y humanista, para el programa impuesto como ampliación del campus universitario del MIT en el barrio universitario de Cambridge, Boston, Massachussets, en torno a dos edificios principales a proyectar: capilla y auditorio. Desde el trabajo de investigación se aporta la información documental necesaria para saber cómo evolucionó desde sus primeros bocetos hasta su construcción. Su nacimiento como necesidad en la sociedad universitaria no fue nada espontáneo, quedando a medias entre la influencia escandinavo - alemana y la tradición americano-luterana de anteriores iglesias neoclásicas herederas del “Plan Akron”. La formación académica y profesional dirigida por su padre, Eliel Saarinen, suman junto a los viajes del arquitecto, una herencia “genética” para con este prototipo ajeno al emergente “estilo internacional” y ayudan a comprender la dimensión compleja de lo que es capaz de representar la capilla. La capilla es refugio emocional de la luz y es un punto de inflexión notable en la recuperación del tipo centrado renovado y evolucionado, que junto con el doble recurso lumínico - efectista, de la vertical para el altar y horizontal inferior, distribuido desde el perímetro ondulado en el interior, el ejemplo es muestra la promoción de una cierta sensibilidad para con las nuevas formas de la "religión" emergentes en la Norteamérica de los años 50. Desde el sincretismo como mecanismo y principal “modus operandi” proyectual, FE versus RAZÓN, aparecen como dualismo permanente en todas las fases del proyecto, desde un proceso de búsqueda de la armonía de ambos y para cada uno de ellos. Con el estudio del modelo prototípico del MIT, buscamos el "patrón" empleado por el arquitecto en su proyección de "nueva iglesia" adaptado a la diversidad cultural y religiosa y de las nuevas y diferentes sensibilidades humanistas para el proyecto. ----------------------------------------------------- SUMMARY--------------------------------------------------- The history of architecture is measured - in part - by the evolution of fashion, periods and styles of religious architecture. In the emergence of the new interfaith university chapel of the 1950s in North America, the chapel of MIT, named after its inauguration as "Kresge Chapel" in honor of its benefactor, was the best example of a prototype, in this time so marked by the emergence of new postwar consciousnesses. The thesis focuses its research on this chapel; how it came about in response to the need to reconcile formal scientific and technological education with religious and humanist training for the program imposed as an extension of the campus of MIT in the university district of Cambridge, Boston Massachusetts, around two main projected buildings : Chapel and auditorium. From research work has been obtained the documentary information necessary to know how it evolved from the first sketches to its construction. Its creation as a necessity of the university society was not at all spontaneous, being halfway between the Scandinavian influence - German and the American Lutheran tradition of neoclassical churches, the heirs to the "Akron Plan". The academic and professional training directed by his father, Eliel Saarinen, together with the travels of the architect, a "genetic" heritage with this external prototype for the emerging "international style", and help to understand the complex dimension of what the chapel is capable of representing. The chapel is an emotional refuge of light and is a remarkable turning point in the recovery of such focused renewed and evolved, along with the double lumen resource - gimmicky, vertical to the altar and lower horizontal, distributed from the undulating perimeter inside, the example is shown to promote a certain sensitivity to the new forms of "religion" but vague religious profile emerging in the America of the 50s. From the syncretism as a mechanism and main "modus operandi" of the project, FAITH versus REASON appears as permanent dualism in all phases of the project from a process of finding the harmony of both and for each of them. With the study of the prototypical model of MIT, we seek the "pattern" used by the architect in his projection of "new church" adapted to the cultural and religious diversity and new and different humanist sensitivities for the project. El desarrollo vierte la luz suficiente para entender los patrones de lo arquitectónico en la capilla, que hacen de ella, la comunión armónica y perfecta de los nombrados opuestos en el campus universitario del MIT. En el camino, además, la investigación arroja luz y orden sobre las fases del proyecto a través de la contribución, recogida, clasificación y orden de los datos, fechas y documentos gráficos, a día de hoy dispersos y confusamente publicados, debido a la no existencia de un estudio profundo y completo como el que pretende ser este trabajo, por ser una obra fundamental en la historia de la arquitectura moderna. El patrón final demostrará el artificio sincrético de cada una de las partes - cada uno en sí misma y cosidas todas - formando el "Ima Summis" de la capilla; resultado de la acción proyectual deducida de su serie genética descifrada. De esta forma, lo sincrético, aparece como el principal atributo del hecho construido, pasando de lo místico a lo científico, de lo intuitivo a lo razonado y siempre con el vehículo de su arquitectura para la interpretación de lo inefable al interior. En cuanto a la estructura de la tesis, se inicia el desarrollo a partir de una introducción en la que se declaran las intenciones y se describe el contexto de lo investigado en torno a la hipótesis principal anunciada en el subtítulo de la tesis. Frente a consideraciones previas de la capilla y de la propia investigación, se expone y explica la hipótesis principal, junto a otros objetivos secundarios. Para finalizar la introducción, se describe el método seguido como estrategia y se justifica la estructura de redacción del documento para la compresión de este trabajo hacia sus conclusiones. Es en el primer capítulo, el C1, donde se inicia el cuerpo central mediante la exposición historiográfica de la situación y contexto previo a la capilla como antecedentes. En un segundo capítulo, el C2, se aborda el estudio del desarrollo del proyecto y de la obra y construcción de la capilla, base documental necesaria. Para ello se inicia con la descripción del lugar, del encargo y del programa, para pasar a mostrar con detalle las distintas propuestas de cada una de las fases del proyecto. En definitiva, qué se proyecto, cómo evolucionó el proyecto y en qué fases transcurrió, para entre otras cuestiones, entender el cambio de estilo desde una fase influenciada por la capilla de Mies construida en el ITT de Chicago, (denominadas en este trabajo por esta influencia como modelos “miesianos”) y la fase reencuentro con el modus de hacer iniciado por su padre Eliel, a través de un modelo a medias de una herencia escandinavo - alemana y la tradición luterano - americana, (denominada en este trabajo como herencia o modelos “saariniana/os”). The development sheds enough light to understand the architectural patterns of the chapel, making it the perfect and harmonic communion named opposites on the campus of MIT. Along the way, furthermore, the research sheds light and order on the phases of the project through the contribution, collection, sorting and order of data, dates and graphic documents, today scattered and confusingly published, due to inexistence of a deep and comprehensive study like this work is meant to be, in the context of such a seminal work in the history of modern architecture. The final pattern will demonstrate the syncretic artifice of each of the parts - each in itself and all together - forming the "Ima Summis" of the chapel; the result of the project action deducted from its deciphered genetic series. Being the SYNCRETIC, the main attribute of the built matter, passing from the mystical to the scientific, from the intuitive to the reasoned and always with the vehicle of architecture as the representation of the ineffable. As for the structure of the thesis, the development starts from an introduction in which the intentions are declared and the context of that which is investigated is described, in terms of the main hypothesis announced in the subtitle of the thesis. Faced with previous considerations of the chapel and the research itself, the principal hypothesis is expressed and explained, along with other secondary objectives. To conclude the introduction, the method followed is described as a strategy and the structuring of the document is justified for the compression of this work towards its conclusions. It is in the first chapter of the thesis, the C1, where the main body of the work is initiated through the historiographical account of the situation and context prior to the chapel as antecedents. A second chapter, C2, addresses the study of the development of the project and of the work and construction of the chapel, based on the necessary documentary evidence. To this end, the analysis begins with the description of the place, the commission and the program, moving on to analyze in detail the various proposals of each phase. What is projected, how it evolved and through what phases passed the project to, among other questions, understand the change in style between the phase of influence of Mies through the projected chapel in the ITT of Chicago chapel (called in this work as "miesian" influences or models) and the reunion with the modus of making initiated by his father Eliel, through a model equally at once of Scandinavian-German heritage and of the American-Lutheran tradition, (referred to in this work as "saarinian" inheritance or models). Para el tercer capítulo, el C3, se llevan a estudio y análisis, los elementos más destacables en los que se prueban las particularidades llamadas “genéticas” en cada uno de las partes principales detectadas en la capilla. Desde ellas se rastrean las influencias - a veces sinergias - que ayudan a justificar y conformar una clasificación genética en torno a cuatro patrones principales, de los que poder discernir al final del capítulo, el “patrón matriz” de la propia capilla en base a la concurrencia de los órdenes arquitectónicos que los conforman. Una vez obtenida la información y orden necesario, se puede afrontar el punto álgido de esta tesis con el cuarto capítulo, el C4, en el que se justifica la capacidad sincrética de la capilla como respuesta a la hipótesis principal señalada en el subtítulo. Para ello se inicia el capítulo con el enfoque y contexto del término “sincretismo” y “sincrético”, aportando la justificación de sus usos para con esta investigación, antes de explicar que la capilla es sincrética por la suma de dos claves fundamentales. La clave primera, correspondiente a la capacidad interconfesional y aconfesional de la capilla, y su capacidad de trascender al interior desde ambas situaciones además de ser reconocible por el religioso y a la vez por el científico. Y la clave segunda, que corresponde a la suma de las distintas partes sincréticas, cada una en si mismas, capaz de sumar todas juntas, este edificio sincrético de los nombrados opuestos. Una vez discernido las claves de lo sincrético en la capilla y a pesar de su doble carácter SACRO Y PROFANO, una comparativa posiciona a la capilla como único entre los ejemplos interconfesionales construidos en los ´50, sin haberse repetido de igual manera y mismo resultado en el tiempo, ni en ninguna otra universidad o centro tecnológico. Así la exposición de este trabajo finaliza con el último capítulo, el C5, en el que desde esa comparativa, una serie de cuestiones unen y distancian a la del MIT y dan acierto a la apuesta inicial, concluyendo que la hipótesis y el patrón de la misma, es el patrón de lo sincrético que modela el ”modus operandi ” del arquitecto. Tras el desarrollo, la investigación cierra filas en torno a cuatro conclusiones para los cuatro capítulos principales; C2, C3, C4, C5. La capilla del MIT como modelo prototípico no se repite en el tiempo, ni en ninguna otra universidad y se posiciona como el mejor prototipo – hito de una nueva arquitectura religiosa universitaria. In the third chapter, C3, we study and analyze the most notable elements in which are found those particularities referred to as "genetic" in each of the principal parts, (see above C3.1.1... - C3.1.8), where these influences - sometimes synergies - are traced, helping to justify and form a classification based on four of those principals (see above C3.2), from which, at the end of this chapter may be discerned a matrix pattern, that of the chapel itself (see above. C3.3.), based on concurrent architectural orders. Once the necessary information and order is obtained, we come to the decisive point in the fourth chapter, C4, where the syncretic capacity of the chapel in response to the main hypothesis indicated in the subtitle of the thesis is justified. For this, the chapter beings with the focus and context of the terms "syncretism" and "syncretic", providing justification for their use for this research, going on to assert that the chapel is syncretic from the sum of two fundamental aspects: the first corresponds to the interfaith and non-denominational capacities of the chapel, its ability to transcend both situations and be recognizable by both the religious and the scientific. The second corresponds to the sum of the different syncretic parts, each in themselves, capable of making together a syncretic building with the opposite. Once discerned the keys to the syncretic and epic in the chapel and despite its dual character both SACRED and PROFANE, a comparatison positions the chapel as being unique among interfaith examples built in the 1950s, without being repeated in the same way and with the same result over time or in any other university or centre of technology. So, the exhibition of this work ends with the last chapter, C5, in which from that comparison a number of issues come together and to distance themselves from MIT and bear out the initial proposition, concluding that the hypothesis and its pattern, the pattern of the syncretic which models the "modus operandi" of the architect to contain the ineffable. The research closes ranks around four conclusions for the four main chapters; C2, C3, C4, and C5 The chapel of MIT as a prototypical model is not repeated in time, or any other university and is positioned as the best prototype - a landmark of a new universitary religious architecture.