5 resultados para Gates.

em Helda - Digital Repository of University of Helsinki


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My thesis concerns the plans drawn up by architect Bertel Liljequist (1885 1954) for an industrial corporation and a city in Finland during the interwar years. These were two quite different clients: the Kymi Company operating in Kuusankoski and the City of Helsinki. My study includes the micro-examination of the wider social issues involved. That the industrial community and factories in Kuusankoski be constructed correctly in a way supporting corporate strategy was of primary importance for the company s operations. Through the planning process for Helsinki s abattoirs, I show how a city dealt with the twin problems of hygiene and increasing demand for food resulting from a growth in population. I clarify how society and its economic, political and class structures affected the practice of architecture and its expression in the built environment. I analyse how the different backgrounds and starting points of the clients affected the construction projects under study and architect Bertel Liljequist s work. In studying Liljequist as an industrial designer, I have considered it vital to ascertain the client s intentions and objectives within the framework of the prevailing social situation. I examine the meanings the client wished the architecture to express and also to communicate to those working in the factory and the area as well as to the workers living on company land. The social outlook of the owners and management of Kymi Company implicitly affected the appearance of the factory. A brick fairface for the factories was a safe and natural material at the beginning of the 1920s when taking into consideration the events of the 1918 Civil War. To have built a White factory in the style of a defence building would have been provocative. Outside the factory gates, however, the company supported White architecture. The company used the factory buildings to manifest its power and the dwellings to bind the workers and make them loyal to the company. Architecture was thus one way in which the company manifested its position as the higher and undisputed authority. The role of the City of Helsinki within the planning process was for its officials to provide expert opinions but also to arrange study trips for the architect and the abattoir s general manager. The city also decided on the standard of the design. The city s responsibility for the health of its inhabitants and the requirements of modern meat production can be seen in the minimal architecture and clear functionality of the plant. The architecture left no doubt about the trustworthiness of the modern city. Translation: Michael Wynne-Ellis

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This thesis reports on investigations into the influence of heat treatment on the manufacturing of oat flakes. Sources of variation in the oat flake quality are reviewed, including the whole chain from the farm to the consumer. The most important quality parameters of oat flakes are the absence of lipid hydrolysing enzymes, specific weight, thickness, breakage (fines), water absorption. Flavour, colour and pasting properties are also important, but were not included in the experimental part of this study. Of particular interest was the role of heat processing. The first possible heat treatment may occur already during grain drying, which in Finland generally happens at the farm. At the mill, oats are often kilned to stabilise the product by inactivating lipid hydrolysing enzymes. Almost invariably steaming is used during flaking, to soften the groats and reduce flake breakage. This thesis presents the use of a material science approach to investigating a complex system, typical of food processes. A combination of fundamental and empirical rheological measurements was used together with a laboratory scale process to simulate industrial processing. The results were verified by means of industrial trials. Industrially produced flakes at three thickness levels (nominally 0.75, 0.85 and 0.90 mm) were produced from kilned and unkilned oat groats, and the flake strength was measured at different moisture contents. Kilning was not found to significantly affect the force required to puncture a flake with a 2mm cylindrical probe, which was taken as a measure of flake strength. To further investigate how heat processing contributes to flake quality, dynamic mechanical analysis was used to characterise the effect of heat on the mechanical properties of oats. A marked stiffening of the groat, of up to about 50% increase in storage modulus, was observed during first heating at around 36 to 57°C. This was also observed in tablets prepared from ground groats and extracted oat starch. This stiffening was thus attributed to increased adhesion between starch granules. Groats were steamed in a laboratory steamer and were tempered in an oven at 80 110°C for 30 90 min. The maximum force required to compress the steamed groats to 50% strain increased from 50.7 N to 57.5 N as the tempering temperature was increased from 80 to 110°C. Tempering conditions also affected water absorption. A significantly higher moisture content was observed for kilned (18.9%) compared to unkilned (17.1%) groats, but otherwise had no effect on groat height, maximum force or final force after a 5 s relaxation time. Flakes were produced from the tempered groats using a laboratory flaking machine, using a roll gap of 0.4 mm. Apart from specific weight, flake properties were not influenced by kilning. Tempering conditions however had significant effects on the specific weight, thickness and water absorption of the flakes, as well as on the amount of fine material (<2 mm) produced during flaking. Flake strength correlated significantly with groat strength and flake thickness. Trial flaking at a commercial mill confirmed that groat temperature after tempering influenced water absorption. Variation in flake strength was observed , but at the groat temperatures required to inactivate lipase, it was rather small. Cold flaking of groats resulted in soft, floury flakes. The results presented in this thesis suggest that heating increased the adhesion between starch granules. This resulted in an increase in the stiffness and brittleness of the groat. Brittle fracture, rather than plastic flow, during flaking could result in flaws and cracks in the flake. These would be expected to increase water absorption. This was indeed observed as tempering temperature increased. Industrial trials, conducted with different groat temperatures, confirmed the main findings of the laboratory experiments. The approach used in the present study allowed the systematic study of the effect of interacting process parameters on product quality. There have been few scientific studies of oat processing, and these results can be used to understand the complex effects of process variables on flake quality. They also offer an insight into what happens as the oat groat is deformed into a flake.

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In cardiac myocytes (heart muscle cells), coupling of electric signal known as the action potential to contraction of the heart depends crucially on calcium-induced calcium release (CICR) in a microdomain known as the dyad. During CICR, the peak number of free calcium ions (Ca) present in the dyad is small, typically estimated to be within range 1-100. Since the free Ca ions mediate CICR, noise in Ca signaling due to the small number of free calcium ions influences Excitation-Contraction (EC) coupling gain. Noise in Ca signaling is only one noise type influencing cardiac myocytes, e.g., ion channels playing a central role in action potential propagation are stochastic machines, each of which gates more or less randomly, which produces gating noise present in membrane currents. How various noise sources influence macroscopic properties of a myocyte, how noise is attenuated and taken advantage of are largely open questions. In this thesis, the impact of noise on CICR, EC coupling and, more generally, macroscopic properties of a cardiac myocyte is investigated at multiple levels of detail using mathematical models. Complementarily to the investigation of the impact of noise on CICR, computationally-efficient yet spatially-detailed models of CICR are developed. The results of this thesis show that (1) gating noise due to the high-activity mode of L-type calcium channels playing a major role in CICR may induce early after-depolarizations associated with polymorphic tachycardia, which is a frequent precursor to sudden cardiac death in heart failure patients; (2) an increased level of voltage noise typically increases action potential duration and it skews distribution of action potential durations toward long durations in cardiac myocytes; and that (3) while a small number of Ca ions mediate CICR, Excitation-Contraction coupling is robust against this noise source, partly due to the shape of ryanodine receptor protein structures present in the cardiac dyad.

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Closure and negotiation constructing professional position in working life The aim of the thesis is to analyse how professional positions are constructed in working life. A professional position refers to a formal professional membership, but also to a position at a work site. Formal jurisdiction provides resources for supporting a position, but the relations, practices and processes at the work site strongly shape it as well. Professional membership includes two gates: obtaining a professional diploma and access to a professional post. The concept of a professional position is based on two sub-concepts: legitimation and authority. Legitimation is society-level jurisdiction over professioning. Legitimation can be claimed in legislation, in the public space and the media, and at the work site. Authority requires constructing professional work territories and practicing authority in work-related decision making processes. The thesis is based on five articles which deal with the following topics: gendered professional careers; organising professional work; the impact of the social and cultural backgrounds when striving for professional positions; and models of research work. The articles represent two types of sociological research: the structural approach with quantitative methodology and the approach of micro-social analysis with qualitative methodology. The first approach was suitable for analyzing professional career formation and its social and ethnic conditions. The second approach has been applied in the articles dealing with the organization of professional work and models of research work. I have combined and analysed the results of these studies under the theoretical frame of the professional position in working life. Legislation is the most powerful form of legitimation. Professional membership is strongly regulated in disciplines where a degree requirement is defined by law. In addition, closures related to social conditions still affect professional positions, but their character is loose and changing. The closures related to social conditions are based on many mutually overlapping principles: social, cultural and ethnic backgrounds and gender. Despite the closures, professional experts have to negotiate their positions, particularly when the situation in the work sites and society changes. Professional authority is reinforced at the organizational level by legislation; when the institutional status of a public sector professional organization is defined by law, it reinforces the professional position of the employees. In the business line of new media, the employees need to negotiate with the management, other professional groups and clients when striving for reinforce their professional position.

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Puu-Käpylä (“Wooden Käpylä”), a neighbourhood of Helsinki, is the earliest example of the Garden City Movement in Finland. The suburb of valuable wooden architecture was built between 1920 and 1925, with the aim to provide a healthy housing area for working-class families with many children. The houses were erected by a co-operative (Käpylän kansanasunnot, “People?s Dwellings”) and they are protected by the city plan since 1960?s. However, the historical value of the sheltered courtyards has not been investigated. The aim of this study was to survey the garden flora of Puu-Käpylä and to evaluate the authenticity of the courtyard gardens. The survey covered the area of one residential quarter (1.2 ha) with twelve 2-storey semi-detached timber houses arranged around a common yard, which was originally appointed for the tenants? vegetable gardens. The houses are still rented, and each flat is allowed a small lot of the courtyard for cultivation. A complete list was made of all perennial, ornamental plant taxa present in the quarter. Spring bulbs were missed due to the timing of the survey. Generally, the plants were recorded on species level, with the exception of common lilacs, shrub roses, irises and peonies that were thoroughly studied for cultivar identification. It was assumed that plants initially grown in the courtyard could be distinguished by studying Finnish garden magazines, books and nursery catalogues published in the 1920?s and by comparing the present vegetation to surviving documents from the quarter. The total number of ornamental plant taxa identified was 172, of which 17 were trees, 47 shrubs, 7 climbers and 101 herbaceous perennials. The results indicated that a major part of the shrubs, climbers and perennials presumably originated from the 1970?s or later, whereas ca. 70 % of the tree specimens were deemed as original. The survey disclosed a heritage variety of common lilac, resembling cultivar „Prince Notger?, a specific peony taxon, Paeonia humilis Retz., cultivated in Nordic countries since long ago, and a few historic iris varieties. Well-preserved design elements included front gardens on one side of the quarter, a maple alley on another side as well as trees at the garden gates. Old garden books and magazines did not shed much light on the Finnish garden flora commonly used in the period when Puu-Käpylä was built. However, they gave a valuable picture of contemporary planting design. Nursery catalogues offered insight into the assortment of ornamental plants traded in the 1920?s. Conclusions on the authenticity of the current flora were mainly drawn on the basis of old photographs and a vegetation survey map drawn in the 1970?s. This study revealed a need for standardization of syrvey methods applied when investigating garden floras. Uniform survey techniques would make the results comparable and enable a future compilation of data from e.g. historic gardens.