929 resultados para Ageing


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The properties of the paper surface play a crucial role in ensuring suitable quality and runnability in various converting and finishing operations, such as printing. Plasma surface modification makes it possible to modify the surface chemistry of paper without altering the bulk material properties. This also makes it possible to investigate the role of the surface chemistry alone on printability without influencing the porous structure of the pigment-coated paper. Since the porous structure of a pigment coating controls both ink setting and optical properties, surface chemical changes created by a plasma modification have a potential to decouple these two effects and to permit a better optimization of them both. The aim of this work was to understand the effects of plasma surface modification on paper properties, and how it influences printability in the sheet-fed offset process. The objective was to broaden the fundamental understanding of the role of surface chemistry on offset printing. The effects of changing the hydrophilicity/ hydrophobicity and the surface chemical composition by plasma activation and plasma coatings on the properties of coated paper and on ink-paper interactions as well as on sheet-fed offset print quality were investigated. In addition, the durability of the plasma surface modification was studied. Nowadays, a typical sheet-fed offset press also contains units for surface finishing, for example UVvarnishing. The role of the surface chemistry on the UV-varnish absorption into highly permeable and porous pigment-coated paper was also investigated. With plasma activation it was possible to increase the surface energy and hydrophilicity of paper. Both polar and dispersion interactions were found to increase, although the change was greater in the polar interactions due to induced oxygen molecular groups. The results indicated that plasma activation takes place particularly in high molecular weight components such as the dispersion chemicals used to stabilize the pigment and latex particles. Surface composition, such as pigment and binder type, was found to influence the response to the plasma activation. The general trend was that pilot-scale treatment modified the surface chemistry without altering the physical coating structure, whereas excessive laboratory-scale treatment increased the surface roughness and reduced the surface strength, which led to micro-picking in printing. It was shown that pilot-scale plasma activation in combination with appropriate ink oils makes it possible to adjust the ink-setting rate. The ink-setting rate decreased with linseed-oil-based inks, probably due to increased acid-base interactions between the polar groups in the oil and the plasma-treated paper surface. With mineral-oil-based inks, the ink setting accelerated due to plasma activation. Hydrophobic plasma coatings were able to reduce or even prevent the absorption of dampening water into pigmentcoated paper, even when the dampening water was applied under the influence of nip pressure. A uniform hydrophobic plasma coating with sufficient chemical affinity with ink gave an improved print quality in terms of higher print density and lower print mottle. It was also shown that a fluorocarbon plasma coating reduced the free wetting of the UV-varnish into the highly permeable and porous pigment coating. However, when the UV-varnish was applied under the influence of nip pressure, which leads to forced wetting, the role of the surface chemical composition seems to be much less. A decay in surface energy and wettability occurred during the first weeks of storage after plasma activation, after which it leveled off. However, the oxygen/carbon elemental ratio did not decrease as a function of time, indicating that ageing could be caused by a re-orientation of polar groups or by a contamination of the surface. The plasma coatings appeared to be more stable when the hydrophobicity was higher, probably due to fewer interactions with oxygen and water vapor in the air.

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The purpose of the study was to describe the experiences of received support of aging employees and their work related self-image in changing working environments. Firstly, theaim was to discover how the support from organisations and leaders was verified. Secondly, the aim was to get answers how employees experienced themselves as workers and as learners in the current work context. Thirdly, the aim was to compare different knowledge information stages and company cultures and how they have influenced the experiences of professional competence development among aging employees. In addition the education- and career backgrounds were investigated to gain more understanding of their role in experiencing support and relation to the occupational self-image. The theoretical frame of reference of this researchis multidisciplinary. The theoretical part focuses on the meaning of work for human being from a sociological, late-modern perspective. On the other hand it examines the ageing process from a physiological and also from a perspective of age discrimination and life control. The occupational selfimage and the strength of motivation has an effect on learning in working life which is crucial and firmpart individual trajectories. According to the theoretical review company culture, leadership and especially the managers' role as a creator of a learning atmosphere are increasingly critical for aging adults' learning when the role of informal work-based learning is increasing. The empirical data was collected with aquestionnaire and interviews, which were carried out in May to October 2001. The data consists of 263 respondents of which further eight persons were interviewed. All respondents were over the age of 45 and represented all levels of their organisations in an IT-technology firm and a chemical industry plant. The central findings in this research show that the aging adults have experienced that theemployers do care about the development of their occupational skills. On the other hand there are fewer concrete activities to reveal this support. There is anobvious disproportion between the expressed aims and the realisation of the activities. Signs of age discrimination are few. The style of management has becomemore supporting for self directed activities which are seen to support adults learning. Higher education and individual activity to seek possibilities to learnwere encouraging the development of occupational skills. Age itself was not a crucial aspect when comparing the experiences among younger (45-54 years) and older (55-64 years) groups. Job satisfaction and professional self esteem seemed tobe considerably strong. The individual characteristics were more important elements in developing occupational skills than the age. The degree of anxiety at work was low. In addition among the older group the strong feeling of coherence and the occupational self image were significant for supporting the professional competence. The motivation to learn was also stable. Among the seniors there was some slight evidence of declining motivation. In the IT-firm the support was experienced stronger for aging employees than in the chemical industry plant. Thosewho had experienced support in the chemical industry plant had higher educational background than the others. In IT-firm they also experienced more support from the manager than in the chemical industry plant. The results show that it is more likely that the differences are caused mostly by the stage of information intensity and the character of company culture which is determined by the activities. IT-business demands constantly accommodation to changes and the chemical industry plant which is representing more traditional business field, where the atmosphere of learning is determined by the traditions of company culture, the changes are carried out slowly.

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Dental oxide ceramics have been inspired by their biocompability and mechanical properties which have made durable all-ceramic structures possible. Clinical longevity of the prosthetic structures is dependent on effective bonding with luting cements. As the initial shear bond strength values can be comparable with several materials and procedures, long-term durability is affected by ageing. Aims of the current study were: to measure the shear bond strength of resin composite-to-ceramics and to evaluate the longevity of the bond; to analyze factors affecting the bond, with special emphasis on: the form of silicatization of the ceramic surface; form of silanization; type of resin primer and the effect of the type of the resin composite luting cement; the effect of ageing in water was studied regarding its effect to the endurance of the bond. Ceramic substrates were alumina and yttrium stabilized zirconia. Ceramic conditioning methods included tribochemical silicatization and use of two silane couplings agents. A commercial silane primer was used as a control silane. Various combinations of conditioning methods, primers and resin cements were tested. Bond strengths were measured by shear bond strength method. The longevity of the bond was generally studied by thermocycling the materials in water. Additionally, in one of the studies thermal cycling was compared with long-term water storaging. Results were analysed statistically with ANOVA and Weibull analysis. Tribochemical treatment utilizing air pressure of 150 kPa resulted shear bond strengths of 11.2 MPa to 18.4 MPa and air pressure of 450 kPa 18.2 MPa to 30.5 MPa, respectively. Thermocycling of 8000 cycles or four years water storaging both decreased shear bond strength values to a range of 3.8 MPa to 7.2 MPa whereas initial situation varied from 16.8. Mpa to 23.0 MPa. The silane used in studies had no statistical significance. The use of primers without 10-MDP resulted spontaneous debonding during thermocycling or shear bond strengths below 5 MPa. As conclusion, the results showed superior long-term bonding with primers containing 10-MDP. Silicatization with silanizing showed improved initial shear bond strength values which considerably decreased with ageing in water. Thermal cycling and water storing for up to four years played the major role in reduction of bond strength, which could be due to thermal fatigue of the bonding interface and hydrolytic degradation of the silane coupled interface.

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Tässä työssä käydään lyhyesti läpi sähkökaapeleiden haurastumisilmiöt säteilyn ja lämmön osalta, näiden yhteisvaikutus kaapelimateriaaleihin sekä yleisimpien ydinvoimalaitoksilla käytettävien kaapeleiden ominaisuuksia. Työssä esitellään myös kaapeleiden kelpoistukseen käytettäviä menetelmiä sekä maailmalla tehtyjä tutkimuksia.

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The general goal of the present work was to study whether spatial perceptual asymmetry initially observed in linguistic dichotic listening studies is related to the linguistic nature of the stimuli and/or is modality-specific, as well as to investigate whether the spatial perceptual/attentional asymmetry changes as a function of age and sensory deficit via praxis. Several dichotic listening studies with linguistic stimuli have shown that the inherent perceptual right ear advantage (REA), which presumably results from the left lateralized linguistic functions (bottom-up processes), can be modified with executive functions (top-down control). Executive functions mature slowly during childhood, are well developed in adulthood, and decline as a function of ageing. In Study I, the purpose was to investigate with a cross-sectional experiment from a lifespan perspective the age-related changes in top-down control of REA for linguistic stimuli in dichotic listening with a forced-attention paradigm (DL). In Study II, the aim was to determine whether the REA is linguistic-stimulus-specific or not, and whether the lifespan changes in perceptual asymmetry observed in dichotic listening would exist also in auditory spatial attention tasks that put load on attentional control. In Study III, using visual spatial attention tasks, mimicking the auditory tasks applied in Study II, it was investigated whether or not the stimulus-non-specific rightward spatial bias found in auditory modality is a multimodal phenomenon. Finally, as it has been suggested that the absence of visual input in blind participants leads to improved auditory spatial perceptual and cognitive skills, the aim in Study IV was to determine, whether blindness modifies the ear advantage in DL. Altogether 180-190 right-handed participants between 5 and 79 years of age were studied in Studies I to III, and in Study IV the performance of 14 blind individuals was compared with that of 129 normally sighted individuals. The results showed that only rightward spatial bias was observed in tasks with intensive attentional load, independent of the type of stimuli (linguistic vs. non-linguistic) or the modality (auditory vs. visual). This multimodal rightward spatial bias probably results from a complex interaction of asymmetrical perceptual, attentional, and/or motor mechanisms. Most importantly, the strength of the rightward spatial bias changed as a function of age and augmented praxis due to sensory deficit. The efficiency of the performance in spatial attention tasks and the ability to overcome the rightward spatial bias increased during childhood, was at its best in young adulthood, and decreased as a function of ageing. Between the ages of 5 and 11 years probably at first develops movement and impulse control, followed by the gradual development of abilities to inhibit distractions and disengage attention. The errors especially in bilateral stimulus conditions suggest that a mild phenomenon resembling extinction can be observed throughout the lifespan, but especially the ability to distribute attention to multiple targets simultaneously decreases in the course of ageing. Blindness enhances the processing of auditory bilateral linguistic stimuli, the ability to overcome a stimulus-driven laterality effect related to speech sound perception, and the ability to direct attention to an appropriate spatial location. It was concluded that the ability to voluntarily suppress and inhibit the multimodal rightward spatial bias changes as a function of age and praxis due to sensory deficit and probably reflects the developmental level of executive functions.

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Foot health is a part of overall health in every age group and its importance increases during ageing. Health care professionals are in a vital position for preventing foot health problems, and identifying and caring them in older people. Despite the rather high number of studies conducted in the field of foot health in older people, reliable and valid nurse-administered foot health assessment instruments seem to be lacking. By identifying foot health in older people, it is possible to develop nursing interventions to enhance safe, independent living at home. The purpose of this three-phase study was to develop an instrument to assess the level of foot health in older people and evaluate foot care practices from the perspective of older people themselves and nurses in home care. The ultimate goal is to prevent foot health problems by increasing the attention paid to older people’s feet and recognizing those foot health problems which need further care; thus not focus on different foot health problems. The study was conducted in different phases and contexts. In phase 1, a descriptive design with a literature review from the Medline (R) and CINAHL databases to explore foot health in older people and nurses’ role in foot health care and pre-post design intervention study in nursing home with nursing staff (n=16) and older residents (n=43) were conducted. In phase 2, a descriptive and explorative study design was employed to develop an instrument for assessing foot health in older people (N=651, n=309, response rate 47%) and explore the psychometrics of the instrument. The data were collected from sheltered housing and home care settings. Finally, in phase 3, descriptive and explorative as well as cross-sectional correlational survey designs were used to assess foot health and evaluate the foot self-care activities of older people (N=651, n=309, response rate 47%) and to describe foot care knowledge and caring activities of nurses (N=651, n=322, response rate 50%) in home care in Finland. To achieve this, the Foot Health Assessment Instrument (FHAI) developed in phase 2 was used; at the same time, this large sample also was used for the psychometric evaluation of the FHAI. The data analysis methods used in this study were content analysis, descriptive and inferential statistics including factor and multivariate analysis. Many long-term diseases can manifest in feet. Therefore, the FHAI, developed in this study consisted of items relating to skin and nail health, foot structure and foot pain. The FHAI demonstrated acceptable preliminary psychometric properties. A great deal of different foot health problems in older people were found of which edema, dry skin, thickened and discoloured toenails and hallux valgus were the most prevalent foot health problems. Moreover, many older people had difficulties in performing foot self-care. Nurses’ knowledge of foot care was insufficient and revealed a need for more information and continuing education in matters relating to foot care in older people. Instead, nurses’ foot care activities were mainly adequate, though the findings indicate the need for updating foot care activities to correspond with the evidence found in the field of foot care. Practical implications are presented for nursing practice, education and administration. In future, research should focus on developing interventions for older people and nurses to promote foot health in older people and to prevent foot health problems, as well as for further development of the FHAI.

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Väestön ikääntyminen pakottaa yhteiskunnan ja julkisen terveydenhuollon muutoksiin. Jotta ikääntyvien ihmisten kotona asuminen voidaan mahdollistaa, palvelujärjestelmän pitää mukautua muuttuvaan tilanteeseen. Tämän diplomityön tarkoituksena on tunnistaa asiakaslähtöisiä lähellä asiakasta tarjottavia palvelukokonaisuuksia. Tutkimuksen teoreettinen viitekehys muodostuu asiakasarvon luomisesta ja palvelutarjoamista. Tarkasteluryhmänä on Etelä-Karjalan alueen 60–90-vuotiaat ja käytetty aineisto on kerätty vastaajilta postitse lähetetyllä kyselyllä. Tutkimus on eksploratiivinen ja tulosten tulkinnassa on hyödynnetty määrällisen tutkimuksen ja verkostoanalyysin menetelmiä. Työn keskeisimmät tulokset ovat tunnistetut asiakassegmentit ja heidän tarpeidensa pohjalta muodostetut palvelupaketit. Tulokset indikoivat asiakkaiden tarpeita ja tuloksia on analysoitu myös tuottajan näkökulmasta. Empiiristen tulosten lisäksi teoriaviitekehystä on kehitetty eteenpäin, jotta palvelukeskeiset teoriat voidaan ymmärtää yritysten näkökulman lisäksi asiakkaan näkökulmasta.

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The Finnish electricity distribution sector, rural areas in particular, is facing major challenges because of the economic regulation, tightening supply security requirements and the ageing network asset. Therefore, the target in the distribution network planning and asset management is to develop and renovate the networks to meet these challenges in compliance with the regulations in an economically feasible way. Concerning supply security, the new Finnish Electricity Market Act limits the maximum duration of electricity supply interruptions to six hours in urban areas and 36 hours in rural areas. This has a significant impact on distribution network planning, especially in rural areas where the distribution networks typically require extensive modifications and renovations to meet the supply security requirements. This doctoral thesis introduces a methodology to analyse electricity distribution system development. The methodology is based on and combines elements of reliability analysis, asset management and economic regulation. The analysis results can be applied, for instance, to evaluate the development of distribution reliability and to consider actions to meet the tightening regulatory requirements. Thus, the methodology produces information for strategic decision-making so that DSOs can respond to challenges arising in the electricity distribution sector. The key contributions of the thesis are a network renovation concept for rural areas, an analysis to assess supply security, and an evaluation of the effects of economic regulation on the strategic network planning. In addition, the thesis demonstrates how the reliability aspect affects the placement of automation devices and how the reserve power can be arranged in a rural area network.

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Tässä pro gradu –tutkielmassa tarkasteltiin ikääntyneiden vanhusten hoitotyötä tekevien työssäjaksamista ja työssä jatkamissuunnitelmia voimavarakeskeisestä näkökulmasta käsin. Kiinnostuksen kohteena olivat myös työyhteisön suhtautuminen ikääntyvään työvoimaan ja keinot, joilla ikääntyneiden työssä jatkamista ja jaksamista tuetaan organisaatiossa. Tutkimusta varten haastateltiin kymmentä yli 55-vuotiasta vanhusten hoitotyötä tekevää henkilöä. Johtopäätösten mukaan työn voimavaroista merkittävimmiksi työssäjaksamisen ja työssä jatkamisen kannalta nousivat hyvät suhteet työtovereihin, toimiva työyhteisö ja asiakkaat. Työn ulkopuolisesta elämästä voimia saatiin mielekkäistä vapaa-ajan puuhista ja läheisistä. Persoonallisuuden voimavaroista keskeiseksi nousi optimistisuus. Eläkkeellä työskentelyaikomusten taustalla olivat usein kokemus työstä nauttimisesta ja hyvä terveys. Toisaalta hyvästä terveydestä haluttiin nauttia myös eläkkeellä.

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Kirjallisuusarvostelu

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The thesis is concerned with the online shopping behavior of older adults, who in this study are at least 60 years old. At the moment, the population is ageing and consumers are buying more and more via the Internet. The objective of the thesis is to understand the large group of older adults in Finland as online customers.The study explores older consumers’ adoption of online shopping with a qualitative research, and it is situated in the research tradition of hermeneutic phenomenology. Phenomenology focuses on the life-world of people. The empirical data was collected by three focus groups with 13 participants altogether. The focus group conversations brought forth that there is not tremendous difference in the motives of older consumers to shop online compared to other age groups. The study strengthened the previous conception of a change toward more ageless market. However, online stores should be designed to accommodate some special needs of older consumers as they occasionally struggle with the logic of websites. Finnish older consumers have adopted online shopping because of perceived convenience and because of tolerable perceived risk during first online shopping experience. Positive experiences strengthen positive attitude toward electronic channel.

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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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Kirjallisuusarvostelu

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Tämän tutkimuksen tarkoituksena on tutkia sitä, miten eri-ikäiset työnteki-jät tulisi huomioida innovatiivisen työskentelyn johtamisessa. Tutkimuk-sessa määritellään, mitä on innovatiivinen työskentely ja miten sitä johde-taan. Innovatiivisella työskentelyllä tarkoitetaan yksilötason toimintaa, jos-sa keskeistä on uusien ideoiden luominen ja tuominen käytäntöön liike-toimintaa hyödyttävällä tavalla. Tutkimuksessa kuvaillaan myös eri-ikäisten ihmisten johtamista ja sen keinoja. Ikäjohtamisen tutkimuksessa on tunnistettu neljä sukupolvea: Z-, Y-, ja X-sukupolvet sekä suuret ikä-luokat. Erot sukupolvien välillä sekä vanhenemisen on tunnistettu ai-heuttavan erilaisuutta työntekijöiden keskuuteen. Tutkimuksessa hyödynnettiin kvalitatiivista tutkimusmetodia ja toteutettiin neljä ryhmähaastattelua, yksi kullekin sukupolvelle. Ryhmähaastatteluis-sa tunnistettiin työyhteisöstä, esimiestyöstä ja ylimmän johdon toiminnas-ta tekijöitä, joilla on vaikutusta eri-ikäisten motivoitumiseen ja innovatiivi-seen työskentelyyn. Tutkimuksessa ei voitu havaita merkittäviä eroja eri-ikäisten innovatiivisen työskentelyn johtamisessa. Iästä riippumatta työn merkityksellisyyden kokeminen on yksilölle tärkeää. Eri-ikäisten innovatii-visen työskentelyn johtamisessa keskeistä on positiivinen johtajuus, jossa hyödynnetään aikaisemmassa innovatiivisen työskentelyn tutkimuksessa esitettyjä johtamisen mekanismeja.