206 resultados para Stockbridge, Mr. (Francis Brown), 1826-1894.


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Alan Earp, president of Brock at the time, presents Welch with a swim cap and Speedo of his own. (1981?)

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The allometric scaling relationship observed between metabolic rate (MR) and species body mass can be partially explained by differences in cellular MR (Porter & Brand, 1995). Here, I studied cultured cell lines derived from ten mammalian species to determine whether cells propagated in an identical environment exhibited MR scaling. Oxidative and anaerobic metabolic parameters did not scale significantly with donor body mass in cultured cells, indicating the absence of an intrinsic MR setpoint. The rate of oxygen delivery has been proposed to limit cellular metabolic rates in larger organisms (West et al., 2002). As such cells were cultured under a variety of physiologically relevant oxygen tensions to investigate the effect of oxygen on cellular metabolic rates. Exposure to higher medium oxygen tensions resulted in increased metabolic rates in all cells. Higher MRs have the potential to produce more reactive oxygen species (ROS) which could cause genomic instability and thus reduced lifespan. Longer-lived species are more resistant to oxidative stress (Kapahi et al, 1999), which may be due to greater antioxidant and/or DNA repair capacities. This hypothesis was addressed by culturing primary dermal fibroblasts from eight mammalian species ranging in maximum lifespan from 5 to 120 years. Only the antioxidant manganese superoxide dismutases (MnSOD) positively scaled with species lifespan (p<0.01). Oxidative damage to DNA is primarily repaired by the base excision repair (BER) pathway. BER enzyme activities showed either no correlation or as in the case of polymerase p correlated, negatively with donor species (p<0.01 ). Typically, mammalian cells are cultured in a 20% O2 (atmospheric) environment, which is several-fold higher than cells experience in vivo. Therefore, the secondary aim of this study was to determine the effect of culturing mammalian cells at a more physiological oxygen tension (3%) on BER, and antioxidant, enzyme activities. Consistently, standard culture conditions induce higher antioxidant and DNA ba.se excision repair activities than are present under a more physiological oxygen concentration. Therefore, standard culture conditions are inappropriate for studies of oxidative stress-induced activities and species differences in fibroblast DNA BER repair capacities may represent differences in ability to respond to oxidative stress. An interesting outcome firom this study was that some inherent cellular properties are maintained in culture (i.e. stress responses) while others are not (i.e. MR).

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The endocrine pancreas of the rock bass (Ambloplites rupestris) was examined by light and electron microscopy. Two cell types with staining properties similar to mammalian A and B cells, and a third, non-staining cell type were found in the spherical pancreatic islets that were surrounded by a connective tissue capsule and embedded in two small masses of exocrine tissue. From an analysis of the ultrastructure of the A and B cells, a secretory cycle for each of these cell types was proposed. The secretory cycle of the A cell consisted of three well defined stages: (1) A cell production stage: during which A granule formation occurred in the sacs of the Golgi apparatus and the cell was characterized by the presence of numerous secretory granules, some elements of lamellar endoplasmic reticulum, and a homogeneously granular nucleus. The cytoplasm contained few distended cisternae, variable numbers of free ribosomes, microtubules and small vesicles. (2) A cell release stage: during which the release of A granules occurred and the cell usually contained several large distended cisternae and variable numbers of secretory granules. Granule release mechanisms included exocytosis, by which individual granules were released into the extracellular space after their membranes fused with the plasmalemma, and emiocytosis, by which one or more granules were released into a large cisterna whose membrane fused with the plasmalemma and formed a pore through which the cisternal contents passed out of the cell. (3) A cell reorganization stage: during which the changeover from the release stage to the production stage occurred and the reorganization of organelles and membrane structures took place. The cell contained few secretory granules and numerous small endoplasmic reticular cisternae. The cytoplasm exhibited less electron density than either of the other two stages. The A granule after formation underwent a series of morphological changes which were described in four numerically identified phases. The secretory cycle of the B cell consisred of two stages: (1) B cell production stage: during which the B granule formation occurred in the sacs of the Go1gi apparatus. The cell was characterized by an irregular outline, the presence of numerous secretory granules, and an irregularly shaped nucleus which contained variable amounts of clumped chromatin. The cytoplasm contained moderate amounts of lamellar endoplasmic reticulum studded with ribosomes, several small vesicles, and an active Go1gi apparatus. (2) B cell release stage: during which the release of B granules occurred. The cell contained a rounded nucleus with dispersed chromatin, several distended endoplasmic reticular cisternae and a variable number of secretory granules. Granule release occu~ by emiocytosis and exocytosis similar to that found for the A cell.

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Description based on: 16th ed. (1901).

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Caption title.

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The collection consists of 37 plans, surveys or maps of the City of Niagara Falls beginning in 1846 until 1928. Some of the plans were created for the Falls Company, a group of land speculators that included Buchanan, Murray, Street, Allen, Robinson and others. Other plans relate to the building of the suspension bridge and the railway. Some plans and drawing may refer to estate documents in RG 167 Niagara South estate and legal documents collection. Item 22 has been scanned for preservation purposes.

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John Smith (1894-1977), son of Daniel Smith and Annie Douglas was a native of Scotland, immigrating to Canada in 1913. He first worked as a coach builder, then as a carpenter, finally developing his own contracting business. During WWI he served overseas with the 10th Battery, RCA as a sergeant. In 1924 Smith married Jean Wood, and together they had a daughter Irene (Hugh Langley). Smith first entered politics in 1940 serving as an alderman for the next 11 years. In 1954 he was elected mayor of the city of St. Catharines, and was twice returned to office by acclamation, serving until 1957 when he successfully ran as the Progressive Conservative candidate representing Lincoln County in the federal election. He won the election by a 10 000 vote majority. He served his constituents in Ottawa until he was defeated in the 1962 election. After leaving politics Mr. Smith was active in his community. He spearheaded the establishment of the St. Catharines Museum, and then was appointed its first director in 1966, serving in that capacity until 1972. He was an active member of the board of governors of the St. Catharines General Hospital and a life member and former president of the Lincoln County Humane Society. In 1971 he was voted Citizen of the Year for the city of St. Catharines. John Smith died on February 8, 1977 and was buried at Victoria Lawn Cemetery. Source: The St. Catharines Standard, February 9, 1977, page 1

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