936 resultados para Bell-Shaped Tuning
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Dedicatio: Henricus Reginaldus Baeck, John Julin nuor.
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The objective of this study was to monitor 11 organophosphorus pesticides in samples of papaya, bell pepper, and banana, commercialized in the metropolitan area of Vitória (ES, Brazil). The pesticides were determined by an optimized and validated method using high performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). All three samples exhibited a matrix effect for most of the pesticides, mainly with signal suppression, and therefore the calibration curves were produced in matrices. Linearity revealed coefficients of determination (r2) greater than 0.9895 for all pesticides and recovery results ranged from between 76% and 118% with standard deviation no greater than 16%. Precision showed relative standard deviation values lower than 19% and HorRat values lower than 0.7, considering all pesticides. Limits of quantification were less than 0.01 mg/kg for all pesticides. Regarding analysis of the samples (50 of each), none of the pesticides exceeded the maximum residue limit determined by Brazilian legislation.
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Kirjallisuusarvostelu
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This thesis presents an experimental study and numerical study, based on the discrete element method (DEM), of bell-less charging in the blast furnace. The numerical models are based on the microscopic interaction between the particles in the blast furnace charging process. The emphasis is put on model validation, investigating several phenomena in the charging process, and on finding factors that influence the results. The study considers and simulates size segregation in the hopper discharging process, particle flow and behavior on the chute, which is the key equipment in the charging system, using mono-size spherical particles, multi-size spheres and nonspherical particles. The behavior of the particles at the burden surface and pellet percolation into a coke layer is also studied. Small-scale experiments are used to validate the DEM models.
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The cytoskeleton is a key feature of both prokaryotic and eukaryotic cells. Itis comprised of three protein families, one of which is the intermediate filaments (IFs). Of these, the IFs are the largest and most diverse. The IFs are expressed throughout life, and are involved in the regulation of cell differentiation, homeostasis, ageing and pathogenesis. The IFs not only provide structural integrity to the cell, they are also involved in a range of cellular functions from organelle trafficking and cell migration to signalling transduction. The IFs are highly dynamic proteins, able to respond and adapt their network rapidly in response to intra- and extra- cellular cues. Consequently they interact with a whole host of cellular signalling proteins, regulating function, and activity, and cellular localisation. While the function of some of the better-known IFs such as the keratins is well studied, the understanding of the function of two IFs, nestin and vimentin, is poor. Nestin is well known as a marker of differentiation and is expressed in some cancers. In cancer, nestin is primarily described as is a promoter of cell motility, however, how it fulfils this role remains undefined. Vimentin too is expressed in cancer, and is known to promote cell motility and is used as a marker for epithelial to mesenchymal transition (EMT). It is only in the last decade that studies have addressed the role that vimentin plays in cell motility and EMT. This work provides novel insight into how the IFs, nestin and vimentin regulate cell motility and invasion. In particular we show that nestin regulates the cellular localisation and organisation of two key facilitators of cell migration, focal adhesion kinase and integrins. We identify nestin as a regulator of extracellular matrix degradation and integrin-mediated cell invasion. Two further studies address the specific regulation of vimentin by phosphorylation. A detailed characterisation study identified key phosphorylation sites on vimentin, which are critical for proper organisation of the vimentin network. Furthermore, we show that the bioactive sphingolipids are vimentin network regulators. Specifically, the sphingolipids induced RhoA kinasedependent (ROCK) phosphorylation at vimentin S71, which lead to filament reorganisation and inhibition of cell migration. Together these studies shed new light into the regulation of nestin and vimentin during cell motility.
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The growing population on earth along with diminishing fossil deposits and the climate change debate calls out for a better utilization of renewable, bio-based materials. In a biorefinery perspective, the renewable biomass is converted into many different products such as fuels, chemicals, and materials, quite similar to the petroleum refinery industry. Since forests cover about one third of the land surface on earth, ligno-cellulosic biomass is the most abundant renewable resource available. The natural first step in a biorefinery is separation and isolation of the different compounds the biomass is comprised of. The major components in wood are cellulose, hemicellulose, and lignin, all of which can be made into various end-products. Today, focus normally lies on utilizing only one component, e.g., the cellulose in the Kraft pulping process. It would be highly desirable to utilize all the different compounds, both from an economical and environmental point of view. The separation process should therefore be optimized. Hemicelluloses can partly be extracted with hot-water prior to pulping. Depending in the severity of the extraction, the hemicelluloses are degraded to various degrees. In order to be able to choose from a variety of different end-products, the hemicelluloses should be as intact as possible after the extraction. The main focus of this work has been on preserving the hemicellulose molar mass throughout the extraction at a high yield by actively controlling the extraction pH at the high temperatures used. Since it has not been possible to measure pH during an extraction due to the high temperatures, the extraction pH has remained a “black box”. Therefore, a high-temperature in-line pH measuring system was developed, validated, and tested for hot-water wood extractions. One crucial step in the measurements is calibration, therefore extensive efforts was put on developing a reliable calibration procedure. Initial extractions with wood showed that the actual extraction pH was ~0.35 pH units higher than previously believed. The measuring system was also equipped with a controller connected to a pump. With this addition it was possible to control the extraction to any desired pH set point. When the pH dropped below the set point, the controller started pumping in alkali and by that the desired set point was maintained very accurately. Analyses of the extracted hemicelluloses showed that less hemicelluloses were extracted at higher pH but with a higher molar-mass. Monomer formation could, at a certain pH level, be completely inhibited. Increasing the temperature, but maintaining a specific pH set point, would speed up the extraction without degrading the molar-mass of the hemicelluloses and thereby intensifying the extraction. The diffusion of the dissolved hemicelluloses from the wood particle is a major part of the extraction process. Therefore, a particle size study ranging from 0.5 mm wood particles to industrial size wood chips was conducted to investigate the internal mass transfer of the hemicelluloses. Unsurprisingly, it showed that hemicelluloses were extracted faster from smaller wood particles than larger although it did not seem to have a substantial effect on the average molar mass of the extracted hemicelluloses. However, smaller particle sizes require more energy to manufacture and thus increases the economic cost. Since bark comprises 10 – 15 % of a tree, it is important to also consider it in a biorefinery concept. Spruce inner and outer bark was hot-water extracted separately to investigate the possibility to isolate the bark hemicelluloses. It was showed that the bark hemicelluloses comprised mostly of pectic material and differed considerably from the wood hemicelluloses. The bark hemicelluloses, or pectins, could be extracted at lower temperatures than the wood hemicelluloses. A chemical characterization, done separately on inner and outer bark, showed that inner bark contained over 10 % stilbene glucosides that could be extracted already at 100 °C with aqueous acetone.
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We investigated the GABA-induced inactivation of V2 neurons and terminals on the receptive field properties of this area in an anesthetized and paralyzedCebus apella monkey. Extracellular single-unit activity was recorded using tungsten microelectrodes in a monkey before and after pressure-injection of a 0.25 or 0.5 M GABA solution. The visual stimulus consisted of a bar moving in 8 possible directions. In total, 24 V2 neurons were studied before and after blocker injections in 4 experimental sessions following GABA injection into area V2. A group of 10 neurons were studied over a short period. An additional 6 neurons were investigated over a long period after the GABA injection. A third group of 8 neurons were studied over a very long period. Overall, these 24 neurons displayed an early (1-20 min) significant general decrease in excitability with concomitant changes in orientation or direction selectivity. GABA inactivation in area V2 produced robust inhibition in 80% and a significant change in directional selectivity in 60% of the neurons examined. These GABA projections are capable of modulating not only levels of spontaneous and driven activity of V2 neurons but also receptive field properties such as direction selectivity.
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Food processes must ensure safety and high-quality products for a growing demand consumer creating the need for better knowledge of its unit operations. The Computational Fluid Dynamics (CFD) has been widely used for better understanding the food thermal processes, and it is one of the safest and most frequently used methods for food preservation. However, there is no single study in the literature describing thermal process of liquid foods in a brick shaped package. The present study evaluated such process and the influence of its orientation on the process lethality. It demonstrated the potential of using CFD to evaluate thermal processes of liquid foods and the importance of rheological characterization and convection in thermal processing of liquid foods. It also showed that packaging orientation does not result in different sterilization values during thermal process of the evaluated fluids in the brick shaped package.
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The objective in this study was to verify the efficiency of different procedures for evaluating the physiological potential of bell pepper seed and identify its relationship with germination at different temperatures and with seedling emergence. Five seed lots each of the Reinger and Sentinel hybrids were used. Seed physiological potential was evaluated by germination, saturated salt accelerated aging (48 h/41 °C), seedling emergence (percentage and speed), and tetrazolium tests (preconditioning at 45 °C/3 h and seed staining at 45 °C/2 h). Germination (percentage and speed) on a thermogradient table at 15 °C, 18 °C, 21 °C, 25 °C and 30 °C was also evaluated the saturated salt accelerated aging and tetrazolium tests are suitable for access the physiological potential of bell pepper seeds. It was also confirmed that vigorous seed lots perform better when exposed to different temperatures during germination.
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Tellerianus
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This study examines adolescent student responses to a women's literature unit taught within a grade 12 Writer's Craft course. Current research (Gilligan, 1989, Pipher, 1994 & Slack, 1999) suggests that there is a great under-representation of female authors in the high school literature curriculum. The use of women's literature may draw attention to important literary figures who are historically overlooked within the curriculum. It gives voice to a marginalized group and presents students with alternative subjects and heroes. It encourages students to develop a critical perspective and reevaluate assumptions about institutions, ideologies, language and culture. It also allows me, as a teacher, to reflect on my own teaching practices and explore alternate feminist pedagogical principles and teaching styles encouraging multiplicity of voices, deconstruction of power relations, and alternative assessment tools within the classroom. As an educator, it is important for me to teach curriculum that is relevant and meaningful to students and help them become critical, self-reflective thinkers. It is also important for me to assist students in their exploration of self and encourage them to expand their awareness of historical, social and global issues. Sylvia Plath's (1963) The belljar is used as the primary text taught within this unit. In this novel, the bell jar is a central image that signifies entrapment and isolation. "To the person in the bell jar, blank and stopped as a dead body, the world itself is the bad dream"(p.l 54). As a metaphor, the bell jar resonates with young readers in a variety of ways.
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The Clemente Course in the Humanities is an anti-poverty intervention for adults who self-identity as "poor" and humanities instructors. The course was created in 1995 by journalist Earl Shorris, who based the curriculum on a Socratic method of pedagogy and the "great books" canon of Robert Hutchins. It began as a community-based initiative in urban US settings, but since 1997 Mayan, Yup'ik and Cherokee iterations have been created, as well as on-campus bridge courses for non-traditional students to explore college-level education in Canada and the USA. The course potentially conflicts with critical pedagogy because the critical theories of Paulo Freire and contemporary cultural studies reject traditional notions of both the canon and teaching. However, a comparison between Shorris' and bell hooks' theories of oppression reveals significant similarities between his "surround of force" and her "capitalist imperialist white supremacist patriarchy," with implications for liberal studies and critical pedagogy.
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Lewis Tyrell married Jane Gains on August 31, 1849 in Culpeper Court House, Virginia. Jane Gains was a spinster. Lewis Tyrell died September 25, 1908 at his late residence, Vine St. and Welland Ave., St. Catharines, Ont. at the age of 81 years, 5 months. Jane Tyrell died March 1, 1886, age 64 years. Their son? William C. Tyrell died January 15, 1898, by accident in Albany, NY, age 33 years, 3 months. John William Taylor married Susan Jones were married in St. Catharines, Ont. on August 10, 1851 by William Wilkinson, a Baptist minister. On August 9, 1894 Charles Henry Bell (1871-1916), son of Stephen (1835?-1876) and Susan Bell, married Mary E. Tyrell (b. 1869?) daughter of Lewis and Alice Tyrell, in St. Catharines Ontario. By 1895 the Bell’s were living in Erie, Pennsylvania where children Delbert Otto (b. 1895) and Edna Beatrice (b. 1897) were born. By 1897 the family was back in St. Catharines where children Lewis Tyrell (b. 1899), Gertrude Cora (b. 1901), Bessie Jane (b. 1902), Charles Henry (b. 1906), Richard Nelson (b. 1911) and William Willoughby (b. 1912) were born. Charles Henry Bell operated a coal and ice business on Geneva Street. In the 1901 Census for St. Catharines, the Bell family includes the lodger Charles Henry Hall. Charles Henry Hall was born ca. 1824 in Maryland, he died in St. Catharines on November 11, 1916 at the age of 92. On October 24, 1889 Charles Hall married Susan Bell (1829-1898). The 1911 Census of Canada records Charles Henry Hall residing in the same household as Charles Henry and Mary Bell. The relationship to the householder is step-father. It is likely that after Stephen Bell’s death in 1876, his widow, Susan Bell married Hall. In 1939, Richard Nelson Bell, son of Charles Henry and Mary Tyrell Bell, married Iris Sloman. Iris (b. 22 May 1912 in Biddulph Township, Middlesex, Ontario) was the daughter of Albert (son of Joseph b. 1870 and Elizabeth Sloman, b. 1872) and Josie (Josephine Ellen) Butler Sloman of London, Ont. Josie (b. 1891) was the daughter of Everett Richard and Elizabeth McCarthy (or McCarty) Butler, of Lucan Village, Middlesex North. According to the 1911 Census of Canada, Albert, a Methodist, was a porter on the railroad. His wife, Josephine, was a Roman Catholic. Residing with Albert and Josie were Sanford and Sadie Butler and Sidney Sloman, likely siblings of Albert and Josephine. The Butler family is descended from Peter Butler, a former slave, who had settled in the Wilberforce Colony in the 1830s. Rick Bell b. 1949 in Niagara Falls, Ont. is the son of Richard Nelson Bell. In 1979, after working seven years as an orderly at the St. Catharines General Hospital while also attending night school at Niagara College, Rick Bell was hired by the Thorold Fire Dept. He became the first Black professional firefighter in Niagara. He is a founding member of the St. Catharines Junior Symphony; attended the Banff School of Fine Arts in 1966 and also performed with the Lincoln & Welland Regimental Band and several other popular local groups. Upon the discovery of this rich archive in his mothers’ attic he became passionate about sharing his Black ancestry and the contributions of fugitive slaves to the heritage Niagara with local school children. He currently resides in London, Ont.
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A St. Catharines Public Schools Honor Pupils certificate presented to Bessie Bell, dated December 8, 1910 and signed by G. E. Lounsbury, Teacher. This certificate was in the possession of the Richard Bell Family of St. Catharines, Ontario.The certificate reads: "Bessie Bell is this day entitled to receive this public expression of approbation for Industry, Good Conduct and Regular Attendance, for the week ending December 8th 1910. Parents are particularly requested to enquire for a card of this kind at the close of each week."
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A single page from the Deaths section of the Bell Family Bible listing the names and dates of death for various members of the family.The handwritten entries appear to read as follows: "John William Taylor, died April 30th Anne Domini 1862; aged 52 years. Jess J Bell died April 11th 1872 O Mary Franices Bell died August 20th 1872. Mrs. Susan Hall. Died May, 24th, 1898 Born January 1st 1829 age. 69 William B Bell died March 19th 1897 Richard Jones died June 6th 1912 Mastam Jone died Charles H. Hall died November 11th 1916."