941 resultados para Karl II, Duke of Brunswick-Lüneburg-Wolfenbüttel, 1804-1873.
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An enhanced electrochemiluminescence (ECL) efficiency is obtained from the ruthenium complex tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)(3)(2+)) by introduction of an ionic liquid (IL) 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF(4)). Upon addition of 1% (v/v) BMImBF(4) to 0.1 mm Ru(bpy)(3)(2+) solution, a maximum increase in ECL intensity is obtained both at an indium tin oxide (ITO) electrode (15-fold) and at a glassy carbon (GC) electrode (5- to 64old). Furthermore, upon addition of 1% (v/v) BMImBF4 to 5 pm Ru(bpy)(3)(2+)/100 mm co-reactant systems at a GC electrode, IL adsorption occurs at the electrode surface, which results in a change of the polarity of the electrode surface. Such functionalization greatly improves the functions of both Ru(bpy)(3)(2+) and ionic liquids, as is demonstrated in the sensitive and selective concentration enrichment of the Ru(bpy)(3)(2+) co-reactants.
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Hydrotalcite-like compounds (HTLcs): CoMAlCO3-HTLcs (M=Cu2+, Ni2+, Mn2+, Cr3+, Fe3+), were synthesized by coprecipitation and characterized with XRD and IR. The catalysis of these HTLcs and their calcined products were studied in the p-cresol oxidation, and the effects of the temperature of HTLcs calcination, the ratio of Co/Cu, different promoters, reaction temperatures and reaction times on reaction activities were investigated. It has been found that calcined HTLcs have higher activity than uncalcined samples and mechanical mixed oxides in this reaction. The best yield was obtained from the CoCuAlCO3-HTLc (Co/Cu/Al=3:1:1) calcined at 450 degrees C. A tentative reaction mechanism was also proposed. (C) 1998 Elsevier Science B.V.
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River training walls have been built at scores of locations along the NSW coast and their impacts on shoreline change are still not fully understood. In this study, the Brunswick River entrance and adjacent beaches are selected for examination of the impact of the construction of major training walls. Thirteen sets of aerial photographs taken between 1947 and 1994 are used in a CIS approach to accurately determine tire shoreline Position, beach contours and sand volumes, and their changes in both time and space, and then to assess the contribution of both tire structures and natural hydrodynamic conditions to large scale (years-decades and kilometres) beach changes. The impact of the training walls can be divided into four stages: natural conditions prior to their construction (pre 1959), major downdrift erosion and updrift accretion during and. following the construction of the walls in 1959 similar to 1962 and 1966. diminishing impact of the walls between 1966 and 1987, and finally no apparent impact between 1987 similar to 1994. The impact extends horizontally about 8 km updrift and 17 km downdrift, and temporally up to 25 years..
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The tris[tetrachlorobenzenediolato]phosphate(v) anion (TRISPHAT) is known to be an efficient NMR chiral shift agent for various chiral cationic species. Here we compare the efficiency of TRISPHAT and of a chiral lanthanide shift reagent for the determination of the enantiomeric purity of the chiral building block [Ru(phen)[2]PY[2]][2][+] which possesses C[2] symmetry. We also discuss our results in terms of the geometry of interaction between the Ru(II) complex and the TRISPHAT anion.
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One hundred and sixteen women with measurable metastatic breast cancer participated in a randomised phase II study of single agent liposomal pegylated doxorubicin (Caelyx) given either as a 60 mg/m2 every 6 weeks (ARM A) or 50 mg/m2 every 4 weeks (ARM B) schedule. Patients were over 65 years of age or, if younger, had refused or been unsuitable for standard anthracyclines. The aims of the study were to evaluate toxicity and dose delivery with the two schedules and obtain further information on the response rate of liposomal pegylated doxorubicin as a single agent in anthracycline nai ve advanced breast cancer. Twenty-six patients had received prior adjuvant chemotherapy (including an anthracycline in 10). Sixteen had received non-anthracycline-based first-line chemotherapy for advanced disease. One hundred and eleven patients were evaluable for toxicity and 106 for response. The delivered dose intensity (DI) was 9.8 mg/m2 (95% CI, 7.2-10.4) with 37 (69%) achieving a DI of >90% on ARM A and 11.9 mg/m2 (95% CI, 7.5-12.8) with 37 (65%) achieving a DI of >90% on ARM B. The adverse event profiles of the two schedules were distinctly different. Mucositis was more common with the every 6 weeks regimen (35% CTC grade 3/4 in ARM A, 14% in ARM B) but palmar plantar erythrodysesthesia (PPE) was more frequent with the every 4 weeks regimen (2% CTC grade 3/4 in ARM A, 16% in ARM B). Confirmed objective partial responses by RECIST criteria were seen with both schedules; 15/51 (29%) on ARM A and 17/56 (31%) on ARM B. Liposomal pegylated doxorubicin showed significant activity in advanced breast cancer with a generally favourable side-effect profile. The high frequency of stomatitis seen with 6 weekly treatment makes this the less preferred of the two schedules tested.
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Stimulation of a mutant angiotensin type 1A receptor (DRY/AAY) with angiotensin II (Ang II) or of a wild-type receptor with an Ang II analog ([sarcosine1,Ile4,Ile8]Ang II) fails to activate classical heterotrimeric G protein signaling but does lead to recruitment of beta-arrestin 2-GFP and activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) (maximum stimulation approximately 50% of wild type). This G protein-independent activation of mitogen-activated protein kinase is abolished by depletion of cellular beta-arrestin 2 but is unaffected by the PKC inhibitor Ro-31-8425. In parallel, stimulation of the wild-type angiotensin type 1A receptor with Ang II robustly stimulates ERK1/2 activation with approximately 60% of the response blocked by the PKC inhibitor (G protein dependent) and the rest of the response blocked by depletion of cellular beta-arrestin 2 by small interfering RNA (beta-arrestin dependent). These findings imply the existence of independent G protein- and beta-arrestin 2-mediated pathways leading to ERK1/2 activation and the existence of distinct "active" conformations of a seven-membrane-spanning receptor coupled to each.
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In celebration of the 250th anniversary of the birth of Charles Carroll of Carrollton, Archaeology in Annapolis was invited to excavate the Carroll House and garden on 107 Duke of Gloucester Street in Annapolis, Maryland. The site, named the St. Mary's Site (18AP45) for the Catholic church on the property, is currently owned by the Redemptorists, a Roman Catholic congregation of priests and brothers who have occupied the site since 1852. Prior to the Redemptorists' tenure, the site was owned by the Carroll family from 1701-1852 and is perhaps best known as the home of Charles Carroll of Carrollton (1737-1832), signer of the Declaration of Independence. Excavations at the site were conducted during four consecutive summer seasons from 1987-1990. The investigation focused on three research questions. The first line of inquiry were questions surrounding the dating, architectural configuration, and artifact deposits of the "frame house," a structure adjoining the west wall of the brick Carroll House via a "passage" and later a three story addition. The frame house was partially demolished in the mid-nineteenth century but the construction was thought to pre-date the brick portion of the house. The second research question was spurred by documentary research which indicated that the property might have been the location of Proctor's Tavern, a late 17th-century tavern which served as the meeting place of the Maryland Provincial Assembly. Archaeological testing hoped to determine its location and, if found, investigate Annapolis' early Euro-American occupation. The third research question focused on the landscape of the site as it was shaped by its occupants over the past three hundred years. The research questions included investigating the stratigraphy, geometry, and architectural and planting features of Charles Carroll of Carrollton's terraced garden built during the 1770s, and investigating the changes to the landscape made by the Redemptorists in the nineteenth and twentieth centuries. While no structural evidence associated with Proctor’s Tavern was uncovered during limited excavations along Spa Creek, the historic shore of Spa Creek was identified, buried beneath deep fill deposits laid down during construction of the Carroll Garden. Features and deposits associated with this period likely remain intact in a waterlogged environment along the southeastern sea wall at the St. Mary’s Site. Evidence of extensive earth moving by Carroll is present in the garden and was identified during excavation and coring. This strongly suggests that the garden landscape visible at the St. Mary’s Site is the intact Carroll Garden, which survives beneath contemporary and late nineteenth century strata. The extant surviving garden should be considered highly sensitive to ground-disturbing activities, and is also highly significant considering demonstrable associations with the Carroll family. Other garden-related features were also discovered, including planting holes, and a brick pavilion or parapet located along Spa Creek to the south of the site. The Duke of Gloucester Street wall was shown to be associated with the Carroll occupation of the site. Finally, intensive archaeological research was directed at the vicinity of a frame house constructed and occupied by the Carrolls to the east of the existing brick house, which was replaced by the Redemptorists in the nineteenth century with a greenhouse. These superimposed buildings were documented in detail and remain highly significant features at the St. Mary’s Site.
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One way we keep track of our movements is by monitoring corollary discharges or internal copies of movement commands. This study tested a hypothesis that the pathway from superior colliculus (SC) to mediodorsal thalamus (MD) to frontal eye field (FEF) carries a corollary discharge about saccades made into the contralateral visual field. We inactivated the MD relay node with muscimol in monkeys and measured corollary discharge deficits using a double-step task: two sequential saccades were made to the locations of briefly flashed targets. To make second saccades correctly, monkeys had to internally monitor their first saccades; therefore deficits in the corollary discharge representation of first saccades should disrupt second saccades. We found, first, that monkeys seemed to misjudge the amplitudes of their first saccades; this was revealed by systematic shifts in second saccade end points. Thus corollary discharge accuracy was impaired. Second, monkeys were less able to detect trial-by-trial variations in their first saccades; this was revealed by reduced compensatory changes in second saccade angles. Thus corollary discharge precision also was impaired. Both deficits occurred only when first saccades went into the contralateral visual field. Single-saccade generation was unaffected. Additional deficits occurred in reaction time and overall performance, but these were bilateral. We conclude that the SC-MD-FEF pathway conveys a corollary discharge used for coordinating sequential saccades and possibly for stabilizing vision across saccades. This pathway is the first elucidated in what may be a multilevel chain of corollary discharge circuits extending from the extraocular motoneurons up into cerebral cortex.
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This paper was selected by the editors of the Journal of Chemical Physics as one of the few of the many notable JCP articles published in 2009 that present ground-breaking research
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The growth behavior of intermetallic layer with or without adding 0.3 wt% Ni into the Sn-0.7Cu solder was studied during the wetting reaction on Cu-substrate and thereafter in solid-state aging condition. The Cu-solder reaction couple was prepared at 255, 275 and 295 °C for 10 s. The samples reacted at 255 °C were then isothermally aged for 2-14 days at 150 °C. The reaction species formed for the Sn-0.7Cu/Cu and Sn-0.7Cu-0.3Ni/Cu soldering systems were Cu6Sn5 and (CuNi)6Sn5, respectively. The thickness of the intermetallic compounds formed at the solder/Cu interfaces and also in the bulk of both solders increased with the increase of reaction temperature. It was found that Ni-containing Sn-0.7Cu solder exhibited lower growth of intermetallic layer during wetting and in the early stage of aging and eventually exceeded the intermetallic layer thickness of Sn-0.7Cu/Cu soldering system after 6 days of aging. As the aging time proceeds, a non-uniform intermetallic layer growth tendency was observed for the case of Sn-0.7Cu-0.3Ni solder. The growth behavior of intermetallic layer during aging for both solders followed the diffusion-controlled mechanism. The intermetallic layer growth rate constants for Sn-0.7Cu and Sn-0.7Cu-0.3Ni solders were calculated as 1.41 × 10-17 and 1.89 × 10-17 m2/s, respectively which indicated that adding 0.3 wt% Ni with Sn-0.7Cu solder contributed to the higher growth of intermetallic layer during aging. © 2006 Elsevier B.V. All rights reserved.