15 resultados para 10 kV

em Helda - Digital Repository of University of Helsinki


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Various reasons, such as ethical issues in maintaining blood resources, growing costs, and strict requirements for safe blood, have increased the pressure for efficient use of resources in blood banking. The competence of blood establishments can be characterized by their ability to predict the volume of blood collection to be able to provide cellular blood components in a timely manner as dictated by hospital demand. The stochastically varying clinical need for platelets (PLTs) sets a specific challenge for balancing supply with requests. Labour has been proven a primary cost-driver and should be managed efficiently. International comparisons of blood banking could recognize inefficiencies and allow reallocation of resources. Seventeen blood centres from 10 countries in continental Europe, Great Britain, and Scandinavia participated in this study. The centres were national institutes (5), parts of the local Red Cross organisation (5), or integrated into university hospitals (7). This study focused on the departments of blood component preparation of the centres. The data were obtained retrospectively by computerized questionnaires completed via Internet for the years 2000-2002. The data were used in four original articles (numbered I through IV) that form the basis of this thesis. Non-parametric data envelopment analysis (DEA, II-IV) was applied to evaluate and compare the relative efficiency of blood component preparation. Several models were created using different input and output combinations. The focus of comparisons was on the technical efficiency (II-III) and the labour efficiency (I, IV). An empirical cost model was tested to evaluate the cost efficiency (IV). Purchasing power parities (PPP, IV) were used to adjust the costs of the working hours and to make the costs comparable among countries. The total annual number of whole blood (WB) collections varied from 8,880 to 290,352 in the centres (I). Significant variation was also observed in the annual volume of produced red blood cells (RBCs) and PLTs. The annual number of PLTs produced by any method varied from 2,788 to 104,622 units. In 2002, 73% of all PLTs were produced by the buffy coat (BC) method, 23% by aphaeresis and 4% by the platelet-rich plasma (PRP) method. The annual discard rate of PLTs varied from 3.9% to 31%. The mean discard rate (13%) remained in the same range throughout the study period and demonstrated similar levels and variation in 2003-2004 according to a specific follow-up question (14%, range 3.8%-24%). The annual PLT discard rates were, to some extent, associated with production volumes. The mean RBC discard rate was 4.5% (range 0.2%-7.7%). Technical efficiency showed marked variation (median 60%, range 41%-100%) among the centres (II). Compared to the efficient departments, the inefficient departments used excess labour resources (and probably) production equipment to produce RBCs and PLTs. Technical efficiency tended to be higher when the (theoretical) proportion of lost WB collections (total RBC+PLT loss) from all collections was low (III). The labour efficiency varied remarkably, from 25% to 100% (median 47%) when working hours were the only input (IV). Using the estimated total costs as the input (cost efficiency) revealed an even greater variation (13%-100%) and overall lower efficiency level compared to labour only as the input. In cost efficiency only, the savings potential (observed inefficiency) was more than 50% in 10 departments, whereas labour and cost savings potentials were both more than 50% in six departments. The association between department size and efficiency (scale efficiency) could not be verified statistically in the small sample. In conclusion, international evaluation of the technical efficiency in component preparation departments revealed remarkable variation. A suboptimal combination of manpower and production output levels was the major cause of inefficiency, and the efficiency did not directly relate to production volume. Evaluation of the reasons for discarding components may offer a novel approach to study efficiency. DEA was proven applicable in analyses including various factors as inputs and outputs. This study suggests that analytical models can be developed to serve as indicators of technical efficiency and promote improvements in the management of limited resources. The work also demonstrates the importance of integrating efficiency analysis into international comparisons of blood banking.

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The main obstacle for the application of high quality diamond-like carbon (DLC) coatings has been the lack of adhesion to the substrate as the coating thickness is increased. The aim of this study was to improve the filtered pulsed arc discharge (FPAD) method. With this method it is possible to achieve high DLC coating thicknesses necessary for practical applications. The energy of the carbon ions was measured with an optoelectronic time-of-flight method. An in situ cathode polishing system used for stabilizing the process yield and the carbon ion energies is presented. Simultaneously the quality of the coatings can be controlled. To optimise the quality of the deposition process a simple, fast and inexpensive method using silicon wafers as test substrates was developed. This method was used for evaluating the suitability of a simplified arc-discharge set-up for the deposition of the adhesion layer of DLC coatings. A whole new group of materials discovered by our research group, the diamond-like carbon polymer hybrid (DLC-p-h) coatings, is also presented. The parent polymers used in these novel coatings were polydimethylsiloxane (PDMS) and polytetrafluoroethylene (PTFE). The energy of the plasma ions was found to increase when the anode-cathode distance and the arc voltage were increased. A constant deposition rate for continuous coating runs was obtained with an in situ cathode polishing system. The novel DLC-p-h coatings were found to be water and oil repellent and harder than any polymers. The lowest sliding angle ever measured from a solid surface, 0.15 ± 0.03°, was measured on a DLC-PDMS-h coating. In the FPAD system carbon ions can be accelerated to high energies (≈ 1 keV) necessary for the optimal adhesion (the substrate is broken in the adhesion and quality test) of ultra thick (up to 200 µm) DLC coatings by increasing the anode-cathode distance and using high voltages (up to 4 kV). An excellent adhesion can also be obtained with the simplified arc-discharge device. To maintain high process yield (5µm/h over a surface area of 150 cm2) and to stabilize the carbon ion energies and the high quality (sp3 fraction up to 85%) of the resulting coating, an in situ cathode polishing system must be used. DLC-PDMS-h coating is the superior candidate coating material for anti-soiling applications where also hardness is required.

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The purpose of this work was to elucidate the ontogeny of interleukin-10 (IL-10) secretion from newborn mononuclear cells (MCs), and to examine its relation to the secretion of interferon-g (IFN-g) and immunoglobulins (Igs). The initial hypothesis was that the decreased immunoglobulin (Ig) synthesis of newborn babies was the result of immature cytokine synthesis regulation, which would lead to excessive IL-10 production, leading in turn to suppressed IFN-g secretion. Altogether 57 full-term newborns and 34 adult volunteers were enrolled. Additionally, surface marker compositions of 29 premature babies were included. Enzyme-linked immunoassays were used to determine the amount of secreted IL-10, IFN-g, and Igs, and the surface marker composition of MC were analyzed with a FACScan flow cytometer. The three most important findings were: 1. Cord blood MC, including CD5+ B cells, are able to secrete IL-10. However, when compared with adults, the secretion of IL-10 was decreased. This indicates that reasons other than excessive IL-10 secretion are responsible of reduced IFN-g secretion in newborns. 2. As illustrated by the IL-10 and IFN-g secretion pattern, newborn cytokine profile was skewed towards the Th2 type. However, approximately 25% of newborns had an adult like cytokine profile with both good IL10 and IFN-g secretion, demonstrating that fullterm newborns are not an immunologically homogenous group at the time of birth. 3. There were significant differences in the surface marker composition of MCs between individual neonates. While gestational age correlated with the proportion of some MC types, it is evident that there are many other maternal and fetal factors that influence the maturity and nature of lymphocyte subpopulations in individual neonates. In conclusion, the reduced ability of neonates to secrete Ig and IFN-g is not a consequence of high IL-10 secretion. However, individual newborns differ significantly in their ability to secrete cytokines as well as Igs.

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Sahateollisuuden tuotantokapasiteetti on vähentynyt viime vuosina paljon. Syvä lama on leikannut vientiä ja myös rakentaminen on hiljentynyt. Tämä on pakottanut sopeuttamistoimiin samaan tapaan kuin massa- ja paperiteollisuuden kohdalla. Mikäli tällekin vuodelle suunnitellut toimet toteutuvat, yhteensä yksitoista sahaa ja seitsemän jalostetehdasta on suljettu. Kapasiteetin leikkaukset koskevat yhteensä kahtatoista maakuntaa ja viittätoista seutukuntaa. Puolet leikkauksista kohdistuu pieniin seutukuntiin, joka lisää aluetalouden sopeutumishaastetta. Tutkimuksessa on selvitetty sahojen ja jalostetehtaiden sulkemisten aluetaloudellisia vaikutuksia seutukuntien taloudelliseen kasvuun ja työllisyyteen. Sahateollisuuden menetyksiä verrattiin maakuntatasolla massa- ja paperiteollisuuden vastaaviin. Lisäksi tarkasteltiin alan kolmea tulevaisuuden kuvaa Suomen tasolla. Laskelmat suoritettiin alueellisella yleisen tasapainon RegFinDyn-simulointimallilla. Tarkasteluperiodi oli sulkemisten osalta vuodet 2004–2013 ja vuodet 2010–2014 tulevaisuuden kuvien kohdalla. Sulkemisten vaikutus seutukuntien taloudelliseen kasvuun näyttäisi jäävän suhteellisen pieneksi. Aluetalous sopeutuisi uuteen tilanteeseen muiden alojen kompensoidessa osan menetyksistä. Talouskasvun menetykset ovat yhteensä 173,8 miljoonaa euroa, jos Varkauden sahaa ei suljeta ja 184,7 miljoonaa, jos sulkeminen tapahtuu. Tilanne näyttäisi samalta työllisyyden suhteen. Työllisyyden menetykset ovat vastaavasti yhteensä 2 693 henkilötyövuotta tai 3 031. Menetysten osuus maakuntien yhteenlasketusta BKT:sta ja työllisyydestä on 0,3 %. Tämä on vähemmän kuin massa- ja paperiteollisuudessa. Ongelmalliseksi tilanteen tekee se, että molemmat alat ovat menettäneet talouskasvua ja työllisyyttä viidessä maakunnassa. ETLA:n sahateollisuuden ja rakentamisen tuotantoennusteiden samoin kuin PTT:n hintaennusteiden mukaan tulevaisuus näyttäisi valoisammalta. Laman pohjan saavuttamisen jälkeen sekä tuotanto että kv-hinnat alkaisivat vahvistua tästä vuodesta lähtien. Tulevaisuuden kuvat muodostettiin näiden suhdanne-ennusteiden pohjalta. Mikäli myönteinen kehitys toteutuisi, Suomen BKT voisi kasvaa yhteensä 300–900 miljoonalla eurolla vuoden 2014 loppuun mennessä. Työllisyys voisi vahvistua 1 000–5 000 henkilötyövuodella. Sahateollisuuden sopeuttaminen tulee jatkumaan, mikäli lama ei kohta hellitä. Alan kehitystä seurataan yleisellä tasolla, mutta myös sopeuttamisen aluetaloudellisten vaikutusten arviointia olisi syytä jatkaa.

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Kelan opintoetuustilasto 2009/10 -julkaisu sisältää keskeiset tiedot Kelan maksamista opintotuista ja koulumatkatuista sekä Kelan myöntämästä aikuiskoulutustukeen liittyvästä opintolainan valtiontakauksesta. Julkaisu tarjoaa tilastoja näiden etuuksien saajista ja maksetuista euromääristä. Opintotuesta esitetään myös opintolainoja, korkeakouluopiskelijoiden ateriatukea ja opintolainavähennystä koskevia tietoja.

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Julkaistu Silva Fennica Vol. 10(4) -numeron liitteenä.

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Tiivistelmien kieli suomi.