1. |
- Olande, Oduor
(författare)
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Students' narratives from graphical artefacts : Exploring the use of mathematics tools and forms of expression in students' graphicacy
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The research concerns presented in this dissertation addresses aspects of students’ interaction with commonly occurring graphical artefacts in teaching and learning environments. In particular, focus is on how the students make sense of these artefacts in relation to subject specific tools and forms of expression.The dissertation comprises of four studies guided by a semiotics cultural- historical perspective to cognition. The first study which is largely quantitative, analyses the percentage scores from students’ responses to selected items from OECD PISA surveys for items containing graphical elements. The second and the third studies in keeping with a more sociocultural perspective to learning as point of departure, examine the students’ collaborative interaction around tasks containing graphical elements. The fourth study explores the nature of students’ solutions from the Swedish national test in mathematics based on a tools and forms of expression sensitive empirically derived construct of Identification contra Critical-analytical approach to graphicacy.The main outcomes of these studies can be summarised as follows: first there is justification for re-examining the predominant characterisation of students’ interaction with graphical artefacts. Secondly, while it is not uncommon for students to take a more visual-perceptive and intuitive approach to graphicacy, results from task items interactions indicate that a Critical-analytical approach seems to be more reliable and capable of yielding desirable outcomes. The outcomes of these studies call for vigilance on the type of tasks used in relation to graphicacy and how these can be used to foster students’ Critical-analytical disposition.
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2. |
- Olsson, Helén, 1961-
(författare)
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Att minska risken för våld och att främja återhämtning i den rättspsykiatriska vården : Patienters och personalens erfarenheter av vägen mot återhämtning
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Detta avhandlingsarbete är utfört inom en rättspsykiatrisk vårdkontext och återspeglar patienters[1] och personals[2] erfarenheter och upplevelser av vändpunkter i samband med minskad risk för våld och återhämtning. Med utgångspunkt från ett holistiskt och salutogent hälsovetenskapligt perspektiv har avhandlingen ett tvärvetenskapligt förhållningssätt. Teoretiska ämnesdiscipliner såsom psykiatrisk omvårdnad, kriminologi och sociologi har influerat arbetet.Avhandlingens övergripande syfte var att utifrån de salutogena aspekterna i det rättspsykiatriska omvårdnadsarbetet undersöka vad som är relaterat till vändpunkter i samband med minskad risk för våld och vad som bidrar till återhämtning. Avhandlingen baseras på fyra olika studier. Syftet med den inledande kvantitativa delstudien (I) var att identifiera och jämföra rättspsykiatriska patienter som sänkt sin bedömda risk för våld med 30 % eller mer enligt riskbedömningsinstrument HCR-20. Resultatet visade att den bedömda risken för våld minskade över tid. En demografisk analys genomfördes för att studera skillnader mellan de patienter som sänkt sin bedömda risk för våld och de som inte sänkt sin risk. Det framgick att rättspsykiatriska patienter som bedömts med hjälp av riskbedömningsinstrumentet HCR-20, minskade den bedömda risken för våld, både på kort och på lång sikt. Den rättspsykiatriska vården fungerade bäst när det gällde att förbättra de kliniska riskfaktorerna (C-skalan).Riskhanteringen (R-skalan) gällande eventuell utskrivning och framtida friförmåner visade inte samma goda progress. Demografiska karaktäristika såsom ålder, alkohol och drogmissbruk och psykiatriska diagnoser var inte relaterade till minskad risk för våld, dock var kvinnliga patienter och patienter utan psykopatidiagnos mer benägna att sänka sin risk för våld. Ett urval av de patienter som minskade sin risk för våld med 30 % eller mer utgjorde basen för delstudie II och III.I delstudie II intervjuades tretton rättspsykiatriska patienter om upplevelser och erfarenheter kring vad som bidrar till minskad respektive ökad risk för våld inne på en rättspsykiatrisk avdelning. Data analyserades med hjälp av en tolkande beskrivning (Interpretive Description). Studien visade att orsakerna till ökad respektive minskad risk för våld var processrelaterad, där interaktioner mellan personal och patienter bidrog till en utveckling som antingen präglades av välbefinnande eller disharmoni. Delstudie II utgjorde en viktig kunskapskälla som präglade ansatsen i delstudie III och IV. Detta med hänvisning till att flertalet patienter i delstudie II lämnade intressanta beskrivningar av vändpunkter i samband med minskad risk för våld och återhämtning.Sålunda intervjuades i delstudie III, tio rättspsykiatriska patienter om deras upplevelser av förändringsprocesser i samband med vändpunkter och återhämtning. Dataanalysen skedde med hjälp av en kvalitativ innehållsanalys. Processen beskrevs utifrån tre faser där man i högriskfasen upplevde kaotiska och överväldigande känslor. Vändpunkten upplevdes som ett känsligt skede som präglades av att tvingas hitta en ny, konstruktiv väg i livet. Återhämtningsfasen präglades av ett accepterande och en mognad. Stöd och erkännande från omgivningen ansåg främja dessa processer.Delstudie IV bestod av intervjuer med tretton personal. Syftet var att belysa upplevelser och erfarenheter kring rättspsykiatriska patienters vändpunkter och återhämtning. Kvalitativ innehållsanalys användes för att analysera data. Beskrivningar kring hur en vändpunkt kunde bevaras och främjas baserades på vikten av att vara uppmärksam, lyhörd och att inte skynda på processen. En vändpunkt upplevdes genom att patienten uppvisade synbara positiva förändringar. Sammansättningen på personalen och patienterna ansågs påverka atmosfären på avdelningen, och bidrog till huruvida processen mot vändpunkter och återhämtning underlättades eller försvårades.Avhandlingen visar hur ett ständigt växelspel mellan patienter och mellan personal bidrog till huruvida vårdatmosfären upplevdes såsom hälsofrämjande eller ej. Vidare framgår att processer kring vändpunkter i samband med minskad risk för våld och återhämtning präglades av känslor av sårbarhet och utsatthet. Processen beskrevs som ett känsligt förlopp som behövde understödjas av förtroendefulla relationer med andra, samt möjligheter att få vistas i en trygg miljö.[1] Den vetenskapliga litteraturen använder sig av begrepp såsom client, consumer, service user eller forensic patient för att beteckna människor som är inskrivna inom den rättspsykiatriska vården. Inom det psykiatriska svenska fältet kan begreppen brukare, vårdtagare eller patient förekomma. I denna avhandling kommer begreppet patient och vårdtagare omväxlande att användas för att beteckna de människor som är föremål för den rättspsykiatriska vården. De patienter som deltagit i avhandlingens två delstudier kommer omväxlande att benämnas såsom deltagare eller patienter, för att åstadkomma en varierande och läsvänlig text.[2] I denna avhandling anser begreppet personal den personalkategori som arbetar med omvårdnad inom en rättspsykiatrisk kontext. Det är främst sjuksköterskor och skötare som inkluderas i begreppet omvårdnadspersonal inom den vetenskapliga litteraturen. Sjuksköterskor benämns såsom registered mental health nurses eller registered nurses. Övrig omvårdnadspersonal tituleras till exempel som nurse manager eller assistant nurses. När begreppen personal, vårdare eller omvårdnadspersonal används i denna avhandling avses då den personalkategori som arbetar närmast patienten med omvårdnad och ingen åtskillnad kommer att göras mellan de båda yrkesgrupperna. Personalen som deltar i delstudie IV har omväxlande kallats för personal eller vårdare.
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3. |
- Nydahl, Erik, 1983-
(författare)
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I fyrkens tid : Politisk kultur i två ångermanländska landskommuner
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Abstract Nydahl, Erik; I fyrkens tid. Politisk kultur i två ångermanländska landskommuner 1860-1930 [Voting by income: The political culture of two Swedish municipalities, 1860–1930] Department of Humanities, Mid Sweden University, SE-871 88 Härnösand, Sweden ISBN: 978-91-86694-05-0, ISSN 1652-893X, Doctoral thesis nr: 100 (2010). Swedish text with a summary in English This dissertation analyses the development of political culture in two Swedish municipalities between the 1860s and the 1930s – a period during which Swedish society underwent major changes. The purpose is to examine the direct and indirect consequences of an evolving industrial society's economic, social and political structures on political culture at local levels. The following factors are the base of the study. At the start of the 1860s, a long-standing Swedish tradition of local self-government was reinforced through a major reform, the Local Government Ordinance of 1862 (1862 års kommunalförfattningar). From this point, each parish formed its own municipality. The new municipalities were given the right to levy taxes and made responsible for welfare and schools, thereby becoming a prominent arena for the exercise of power at local levels. The municipal reform of 1862 was carried out at a time when Swedish society was transitioning as the industrialisation process accelerated during the latter part of the 1800s. Gradually, the old structure of an agricultural society was cast aside in favour of a new, modern industrial society. Naturally, also the municipalities changed – directly and indirectly. For some municipalities, adjustments were significant; for others, less so. Part of this process was the reformation of voting rights from plutocratic to public and equal. Another part was the reorganisation of municipal government from direct government via municipal meetings to representative government via municipal councils. Two main issues are formulated and answered in the dissertation. The one addresses who or which had the power over local politics and how the situation changed over time. The second addresses in what way municipal representation changed form with the modernisation of the municipalities. The empirical survey comprises a comparative case study between two municipalities in the northern part of Sweden. The one municipality, Ytterlännäs, was early the site for large-scale sawmill industry. The second municipality, Stigsjö, retained its agricultural structure throughout the entire period in question. The comparison makes it possible to analyse the impending industrial society from two different poles. In the 1800s, local politics was considered to be a completely different sort than politics at a national level. The difference was that local politics, referred to as “the municipal”, was seen as non-political and unaffiliated with those conflicts addressed at national levels, referred to as “the political”. The dissertation demonstrates two different models of how modern municipal politics evolved from the municipal meetings of the 1800s. While the starting point was the same in both municipalities, the paths diverged in the early 1870s. In the agricultural municipality of Stigsjö, it was “business as usual”. In the industrial municipality of Ytterlännäs, however, confrontation arose between enterprises and farmers and eventually, a labour movement emerged demanding the right of participation. The dissertation shows that the distinction between “municipal” and “political” was obliterated in the beginning of the 1900s, paving the way for a new concept – municipal politics. This process occurred in a very palpable way in Ytterlännäs but eventually, Stigsjö was forced to conform. The new municipal politics was, so to speak, the final station in both municipalities. In conjunction with party politicisation of local politics, the criteria and seats for the municipal representatives changed. When party affiliation became an important criterion, professional affiliation became less relevant. Party bloc seats replaced the independent seats, and representatives were eventually paid remuneration. Keywords: Political culture, politics, voting right, municipal politics, industrial society, industrialisation, elected representatives, representation, temperance movement, labour movement, popular movements, political parties, modernisation
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4. |
- Afewerki, Samson, 1985-
(författare)
-
Development of catalytic enantioselective C-C bond-forming and cascade transformations by merging homogeneous or heterogeneous transition metal catalysis with asymmetric aminocatalysis
- 2014
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chiral molecules play a central role in our daily life and in nature, for instance the different enantiomers or diastereomers of a chiral molecule may show completely different biological activity. For this reason, it is a vital goal for synthetic chemists to design selective and efficient methodologies that allow the synthesis of the desired enantiomer. In this context, it is highly important that the concept of green chemistry is considered while designing new approaches that eventually will provide more environmental and sustainable chemical synthesis.The aim of this thesis is to develop the concept of combining transition metal catalysis and aminocatalysis in one process (dual catalysis). This strategy would give access to powerful tools to promote reactions that were not successful with either transition metal catalyst or the organocatalyst alone. The protocols presented in this thesis based on organocatalytic transformations via enamine or iminium intermediates or both, in combination with transition metal catalysis, describes new enantioselective organocatalytic procedures that afford valuable compounds with high chemo- and enantioselectivity from inexpensive commercial available starting materials. In paper I, we present a successful example of dual catalysis: the combination of transition metal activation of an electrophile and aminocatalyst activation of a nucleophile via enamine intermediate. In paper II, the opposite scenario is presented, here the transition metal activates the nucleophile and the aminocatalyst activates the electrophile via an iminium intermediate. In paper III,we present a domino Michael/carbocyclisation reaction that is catalysed by a chiral amine (via iminium/enamine activation) in combination with a transition metal catalysts activation of an electrophile. In paper IV, the concept of dual catalysis was further extended and applied for the highly enantioselective synthesis of valuable structural scaffolds, namely poly-substituted spirocyclic oxindoles. Finally, in paper V the concept of dual catalysis was expanded, by investigating more challenging and environmentally benign processes, such as the successful combination of a heterogeneous palladium and amine catalysts for the highly enantioselective synthesis of functionalised cyclopentenes, containing an all carbonquaternary stereocenter, dihydrofurans and dihydropyrrolidines.
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5. |
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6. |
- Ainegren, Mats
(författare)
-
Roller skis' rolling resistance and grip characteristics : influences on physiological and performance measures in cross-country skiers
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to investigate roller ski characteristics; classical and freestyle roller skis’ rolling resistance coefficients (μR) and classical style roller skis’ static friction coefficients (μS), and to study the influence of different μR and μS on cross-country skiers’ performance and both physiological and biomechanical indices. The aim was also to study differences in skiing economy and efficiency between recreational skiers, female and male junior and senior elite cross-country skiers.The experiments showed that during a time period of 30 minutes of rolling on a treadmill (warm-up), μR decreased significantly (p<0.05) to about 60-65 % and 70-75 % of its initial value for freestyle and classical roller skis respectively. Also, there was a significant influence of normal force on μR, while different velocities and inclinations of the treadmill only resulted in small changes in μR.The study of the influence on physiological variables of a ~50 % change in μR showed that during submaximal steady rate exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non-significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a change in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non-significant or small.The study of classical style roller skis μS showed values that were five to eight times more than the values of μS reported from on-snow skiing with grip-waxed cross-country skis.The subsequent physiological and biomechanical experiments with different μS showed a significantly lower skiing economy (~14 % higher v̇O2), higher heart rate, lower propulsive forces coming from the legs and shorter time to exhaustion (~30 %) when using a different type of roller ski with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a (similar) higher μS.The part of the thesis which focused on skiing economy and efficiency as a function of skill, age and gender, showed that the elite cross-country skiers had better skiing economy and higher gross efficiency (5-18 %) compared with the recreational skiers, and the senior elite had better economy and higher efficiency (4-5 %) than their junior counterparts, while no differences could be found between the genders.
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7. |
- Alam, Mohammad Anzar
(författare)
-
Online optical method for real-time surface measurement using line-of-light triangulation
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Real time paper surface-web measurement is one of the challenging research fields. The traditional laboratory method has many limitations and is unable to measure the entire tambour during the manufacturing process. It has been necessary to develop an online technique that could measure the surface topography in real time. An optical technique was developed, based on laser triangulation, and is applied to develop a new prototype device, which characterizes high speed paper-web surfaces over a wide scale of spatial wavelengths spectrum and computes the surface roughness in real time. The used multi channel pulsed laser diode, source of illumination onto the paper-web, is of benefit due to its low coherence length and is capable to deliver a powerful burst of light beam over a 1 µs duration, which delivers energy of 100 µJ per pulse. The short exposure time avoids blurriness in the acquired images which could possible due to the high speed and vibrations on the paper-web.The laser beam is shaped into a narrow line-of-light using cylindrical lenses and is projected onto a paper-web surface, which covers a physical length of about 210 mm. The created line-of-light cross section full width at half maximum, FWHM Gaussian distribution, is 2-3 pixels on the image. The line-of-light is projected onto the paper-web perpendicular to the plane of the surface. The low angled, low specular, reduced coherence length, scattered reflected laser line is captured by the 3 CCD sensors, which are synchronized with the laser source. The low specular light ensures to avoid saturation of the imaging sensors if the surface is very smooth, and obliquely captures the z-directional fine feature of the surface.The scattered phenomenon of the reflected light is responsible for the surface irregularity measurements. The basic image processing algorithm is applied in order to remove noise and cropped the images widthwise so that only pixels above a preset threshold gray level can be processed, which enables efficient real time measurement. The image is transformed into a 1D array using the center of gravity, COG. The accuracy and precision of the COG depends on the line-of-light FWHM, which, in turn, is responsible for the accuracy, noise and the resolution of the developed technique. The image subpixel resolution achieved is 0.01 times a pixel and uuncertainty in the raw data is 0.43 µm while it is 0.05 µm in the rms roughness.The signal processing steps combining the B-Spline filter and the filter in the spatial frequency domain were employed in order to separate roughness, waviness, and form and position error in the raw profile. The prototype is designed to measure online surface roughness and to characterize surface in a spatial wavelength spectrum from 0.09 to 30 mm, which is extendable to any required spatial range in order to cover a wide scale surface feature such as micro roughness, macro roughness and waviness. It is proven that exploitation of a simple laser triangulation technique could lead to an improvement in the overall quality and efficiency in the paper and paperboard industries and it can also be of potential interest for the other surface characterization problems.
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8. |
- Andersson, Ewa, 1980-
(författare)
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Oberoendets praktik
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The Independent PracticeDuring the last hundred years, the music industry has evolved with the record labels playing a central role. However, many argue that this situation is about to change as record sales have decreased during the last ten years. This imminent change in the music industry will not only affect the multinational record labels, but also the independent record labels. As record sales have decreased during the last ten years, the number of members in the Swedish Independent Music Producers Association (SOM) has increased and the association now includes 300 independent record labels which are responsible for around 30 percent of the music being produced in Sweden. However, they can be considered a dominated group within the music industry, since they only have around 10 percent of the total market shares when it comes to selling figures. Considering the changes in record sales, the domination of the major record labels and the somewhat fascinating growth of independent actors during turbulent times, this thesis will study how the Swedish independent actors relate to the practices and ideals relevant in the daily work of running an independent record label. The practices studied in this thesis are the practice of work, the practice of recognition and the practice of content production.The purpose of this thesis is to analyse how independence is constructed among the members of SOM. The thesis is based on material collected in a web survey as well as seven interviews with representatives of indie labels. The web survey was distributed to all members of SOM, and the interviewed informants were selected by snowball sampling, using a locator to find informants. The survey material was analysed with cluster and variance analysis, while the interview material was analysed using content analysis – searching for themes connected to the practices. All material is understood through the theoretical frame of the field theory.The main results of the study are that there are different ways of relating to practices among the Swedish independent actors, and that these ways of relating are closely connected to their position within the field. There are common ways of relating to practices such as always promoting DIY, the importance of music and the need to resist the dominance of the major labels. However, the independent actors are not consistent in how these commonalities work in practice. For example, DIY is not applied if it is not economically necessary, and the need to resist the major labels is only apparent when the independent actor has a weaker position within the field. The more established an independent actor is within the field, the lesser resistant he is against the dominating structures of the music industry. As a result of a weakening resistance against the major labels, the independent actors turn to struggle each other.
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9. |
- Andresen, Edith
(författare)
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Dressed for success : designing and managing regional strategic networks
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Inter-organizational network initiatives such as regional strategic networks (RSNs) are often used by firms and public agencies to support regional development and competitiveness. RSNs are designed networks managed by a hub and financed by public or private means. RSN management is complex as members are autonomous and initially often loosely connected. The effects of RSNs on regional development are disputed as engineered relationship development may interfere with ongoing business relationships. Despite this, vast public funds are being invested in collaborative initiatives. Identifying factors affecting RSN performance will provide a better basis for evaluating and managing such initiatives.Based on concepts such as actors, resources, and activities findings are reported from longitudinal case-studies built on interviews with 68 members and hubs in four RSNs. Data were also collected through participant observation, conversations, archival data and emails. Findings indicate that factors such as evaluation criteria, member composition, relationships, location, goals, the hub, physical and human resources, knowledge sharing and development, resources, policies and norms, social activities, and communication exert an impact on entrepreneurship and cooperation.The first paper focuses on factors such as actor composition, actor goals, number of actors, and activities facilitating relationship development and commitment. The second paper identifies a framework of seven tasks to be performed by the hub. The effects on development of preferences and atmosphere are dealt with in the third paper. Effects of cooperation between public/private sector and universities are addressed in the fourth paper, and entrepreneurial processes in network contexts are analyzed in the fifth one.The important management role of the hub is emphasized as is carefully considered member composition. Relationships and commitment are found to be crucial. These factors are not covered by national and regional performance criteria. They merit a place of their own.
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10. |
- Arvidson, Catarina, 1959-
(författare)
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Genuspedagogers berättelser om makt och kontroll
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis 14 gender pedagogues’ stories about power and control are described and analysed. Here the term gender pedagogue refers to educators who have participated in further training in gender and gender equality studies. The training programme was the result of an initiative taken by the former Social Democratic government. The intention of the government was that those who participated in the training programme would then work as resource persons in the work for gender equality in preschools and schools (Frånberg, 2010; Regeringen, 2001a, 2001b; Wahlgren, 2009). The purpose of this study is to describe and analyse the gender pedagogues’ access to power and control in work for change. The theoretical framework chosen for the study consists of Basil Bernsteins concepts classification and framing (Bernstein, 1977, 2000) and Hildur Ve’s (1999a, 1999b) use of the concepts technical limited rationality and care work rationality. The empirical evidence is based on observations in a seminar series on gender issues and semi-structured interviews. The results of the interviews are presented as stories which have been created in the interplay between the gender pedagogues and the interviewer. One conclusion that can be drawn from the stories is that power relations and gender patterns on many different levels influenced the possibilities of the gender pedagogues for power and control. Power and control in the relation between technical limited rationality and care work rationality is expressed in different ways. It is seen in the possibilities and descriptions of resistance and difficulties. Resistance and difficulties depended, according to the gender pedagogues, on the differences between their own view of knowledge and that of others. If gender and gender equality was not considered to be an important area of knowledge, possibilities for power and control decreased.
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11. |
- Bader, Sebastian
(författare)
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On the lifetime and usability of environmental monitoring wireless sensor networks
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wireless sensor networks have been demonstrated, at an early stage in their development, to be a useful measurement technology for environmental monitoring applications. Based on their independence from existing infrastructures, wireless sensor networks can be deployed in virtually any location and provide sensor samples in a spatial and temporal resolution, which otherwise would only be achievable at high cost or involve significant work by humans.The feasibility of the usage of wireless sensor networks in real-world applications, however, is only maintained if certain technological challenges are overcome. Amongst these challenges, are the limited lifetime of the distributed sensor nodes, and user interfaces, which allow for the technology to be utilized in an efficient manner. Contributions to the solution of these challenges have been the objective of this thesis.After an analysis of the contributions wireless sensor networks can provideto the application domain of environmental monitoring, and the introductionto the restrictions, which are posed by a limited operational lifetime and lowsystem usability, these issues are addressed at the system level of sensor nodedevices.The lifetime of sensor nodes, which is closely linked to the lifetime of thecomplete wireless sensor network, is addressed with regards to the energyefficiency of nodes, as well as the utilization of solar energy harvesting inorder to increase the available energy resources. With respect to energyefficiency, an analysis has been performed of the contributions to the energyconsumption of environmental monitoring sensor nodes, which leads to thedesire to minimize the nodes' duty cycles and quiescent currents. A sensornode design is presented, which features energy efficiency as a key attribute by utilizingmodern semiconductor architectures. Moreover, an argument for the usage of synchronization-based, contention-free communication is madein order to reduce active communication periods and, thus, the duty cycleof a sensor node. A synchronization method with its focus on low protocoloverhead is introduced as a basis for such communication forms. After an initial feasibility study in relation to using battery-less solar energyharvesting architectures in locations with limited solar irradiation, multiplearchitectural implementations are analyzed in a comparative manner.Among these comparisons is an analysis of short-termenergy storage devices in the form of double-layer capacitors and thin-film batteries, which provide prolonged component lifetimes than those for conventional secondary batteries, but which can only buffer for short periods of time due to their limited energy capacity. In order to be able to dimension such energy harvesting systems with respect to the individual application constraints at hand, state of charge simulations are proposed. Amethod for such simulations is presented and demonstrated for the implementation of an energy harvester model on a component basis. While the modeling in this manner is time consuming, the model can predict the state of charge of the energy buffer in the architecture with a high level of accuracy. Finally, a method for the systematic evaluation of solar energy harvesting architectures is presented. The presented method can be summarized as a solar energy harvesting testbed, which utilizes configurable energy harvesting circuits in order to create a deploy-once-test-many type of system. The output results of this testbed can significantly improvethe efficiency of architecture comparisons and system modeling.Contributions to the improvement of the usability of wireless sensor nodesare made on two separate levels, namely, developer usability and end userusability. A method for the programming of sensor nodes based on hierarchical finite state machines is presented, which improves the usability of software development by creating familiarity for technically experiencedusers. Moreover, the utilization of finite state machine principles allowsfor the software to be developed in a systematic andmodular manner. Asimplemented applications typically require to be verified, which, in the environmental monitoring domain, usually results in outdoor deployments,usability considerations for sensor nodes are presented, which can simplifythis process. Special attention has been paid in order for these improvements to be achieved with low overheads. While software development is a familiar concept for most system developers, this is not the case for the end users of these systems, who are typically domain experts. In order to allow for wireless sensor nodes to be operatedby domain experts, a method for the configuration of sensor nodes has been proposed.The method uses a combination of graphical specification of the node behavior and a configurable sensor node. Theevaluation of this method, which has been based on a proof-of-concept implementation, demonstrated that the performance can remain high, while end users, without technical experience, are enabled to configure sensor nodes without prior training.In summary, the contributions, presented in this thesis, address systemlifetime and usability with regards to the sensor node level. The results haveled to the implementation of an energy efficient sensor node, which allows for the operation frombattery-less solar energy harvesting sources. Furthermore, support tools for the implementation of these nodes, both on the hardware and software level, have been proposed.
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12. |
- Bjärtå, Anna, 1974-
(författare)
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FEAR - A process influenced by concurrent processing demands
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Fear is a central aspect in mammalian evolution, prompting escape from and avoidance of threat and dangers. Therefore, it is reasonable to believe that we have a well developed system to detect dangers and quickly respond to them. It has been shown that threatening information has an advantage in information processing; it seems to promote a rapid capture of selective attention and puts demand on processing resources. It has been suggested that the elicitation of fear occurs automatically, and that it is independent of and impenetrable to cognition.The idea with the present research is that fear processing is dependent on all concurrent internal or external processing demands. One visual search study (Study II) and two secondary task studies (Study I & III) have been conducted to investigate if external or internal distraction can interfere with fear processing. In order to provoke fear responses, spider or snake fearful individuals have been exposed to pictures of their feared stimulus. The aim of Study II was to investigate if the selective attention to fear stimuli could be influenced by contextual factors, such as the nature of the distracting stimuli in a visual search. Study I and III aimed to investigate manipulation of resources allocated to fear stimuli. In Study I, task demand was used as the manipulation, and in Study III an internal cognitive directive was used. The results from these studies indicate that fear is susceptible to manipulation by both external and internal means. By changing circumstances in the surrounding or in the individuals’ internal states, responses to threatening stimuli can be altered. This means that processing of threatening stimuli is influenced by other concurrent processing demands, suggesting that a fear response is not occurring as an isolated and impenetrable process. In an evolutionary perspective, a fear system that is easily triggered but has access to cognitive evaluation at all times ought to be far more flexible, thus creating a better chance for survival than a modular and impenetrable fear system.
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13. |
- Björklund, Glenn, 1972-
(författare)
-
Metabolic and Cardiovascular Responses During Variable Intensity Exercise
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Previous research investigating endurance sports from a physiological perspectivehas mainly used constant or graded exercise protocols, although the nature ofsports like cross-country skiing and road cycling leads to continuous variations inworkload. Current knowledge is thus limited as regards physiological responses tovariations in exercise intensity. Therefore, the overall objective of the present thesiswas to investigate cardiovascular and metabolic responses to fluctuations inexercise intensity during exercise. The thesis is based on four studies (Studies I-IV);the first two studies use a variable intensity protocol with cardiorespiratory andblood measurements during cycling (Study I) and diagonal skiing (Study II). InStudy III one-legged exercise was used to investigate muscle blood flow duringvariable intensity exercise using PET scanning, and Study IV was performed toinvestigate the transition from high to low exercise intensity in diagonal skiing,with both physiological and biomechanical measurements. The current thesisdemonstrates that the reduction in blood lactate concentration after high-intensityworkloads is an important performance characteristic of prolonged variableintensity exercise while cycling and diagonal skiing (Studies I-II). Furthermore,during diagonal skiing, superior blood lactate recovery was associated with a highaerobic power (VO2max) (Study II). Respiratory variables such as VE/VO2, VE/VCO2and RER recovered independently of VO2max and did not reflect the blood lactate oracid base levels during variable intensity exercise during either cycling or diagonalskiing (Studies I-II). There was an upward drift in HR over time, but not inpulmonary VO2, with variable intensity exercise during both prolonged cyclingand diagonal skiing. As a result, the linear HR-VO2 relationship that wasestablished with a graded protocol was not present during variable intensityexercise (Studies I-II). In Study III, blood flow heterogeneity during one-leggedexercise increased when the exercise intensity decreased, but remained unchangedbetween the high intensity workloads. Furthermore, there was an excessiveincrease in muscular VO2 in the consecutive high-intensity workloads, mainlyexplained by increased O2 extraction, as O2 delivery and blood flow remainedunchanged. In diagonal skiing (Study IV) the arms had a lower O2 extraction thanthe legs, which could partly be explained by their longer contact phase along withmuch higher muscle activation. Furthermore, in Study IV, the O2 extraction in botharms and legs was at the upper limit during the high intensity workload with nofurther margin for increase. This could explain why no excessive increase inpulmonary VO2 occurred during diagonal skiing (Study II), as increased O2extraction is suggested to be the main reason for this excessive increase in VO2(Study III).
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14. |
- Björkman Randström, Kerstin
(författare)
-
Hemmet som arena för äldres rehabilitering
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Avhandlingens övergripande syfte var att studera multidisciplinära teams, äldre personers och familjemedlemmars erfarenheter av hemrehabilitering. Avhandlingen baseras på fyra studier (I-IV). Alla studierna har en kvalitativa beskrivande design. Datamaterialet utgjordes av fokusgruppsintervjuer med personal arbetande i team i kommunal hälso- och sjukvård (I), intervjuer med äldre personer, över 65 år, som vårdats på sjukhuset och därefter fortsatt rehabilitering i hemmet (II,III,IV), samt familjemedlemmar involverade i de äldres rehabilitering (II).Studie I visade på betydelsen av att möta äldres individuella behov och att arbeta utifrån ett rehabiliterande förhållningssätt i avsikt att ge en hjälp som inte innebär att ta över handlingar från den äldre. Väsentligt var att i teamet reflektera över hur man agerar utifrån den egna professionen för att kunna utveckla ett rehabiliterande förhållningssätt i det dagliga arbetet. I resultatet framkom att teamen uppfattade hemrehabilitering som positiv för de äldre, men mindre lämpligt om de äldre var svårt sjuka och de kände sig otrygga i sitt hem. Respekt för de äldres integritet i deras hem och att göra de närstående delaktiga i rehabiliteringen betonades. Resultatet visade på att för att kunna utveckla samarbetet i teamet finns behov av att diskutera varje professions ansvarsområde och klargöra gränser mellan varandras ansvarområden. Behovet av att tillföra psykosocial kompetens i teamet framhölls för att möta de äldres behov. I studie II framkom att de äldre upplevde rehabiliteringen vara en balansgång i att känna av vad kroppen orkar med för dagen och vad som är realistiskt att uppnå för att känna välbefinnande. Tryggheten i att ha någon i familjen nära sig i hemmet var oumbärligt för att våga utföra träning och vardagliga aktiviteter. Resultatet visar på de äldres upplevelse av otillfredsställelse med att vara beroende av andra. Familjemedlemmar var engagerade i de äldres rehabilitering genom att finnas till hands, hjälpa till och vara stödjande, vilket var en självklar handling men också utmanande i att kunna hjälpa på rätt sätt. Bristande information om hjälpmedels funktion och användning skapade frustration. Resultatet visar att både de äldre och deras familjemedlemmar ser hemmiljön bidra till att underlätta rehabilitering. Det som försvårar är när gränsen för det egna hemmet inskränkts i och med att och personal ofta gick "in och ut" i det egna hemmet.Studie III visar på ett flertal faktorer i de äldres vardag och i det omgivande samhället som inverkat underlättande eller hindrande på aktiviteter och delaktighet vid hemrehabilitering. Resultatet beskrivs utifrån Klassifikation av funktionstillstånd, funktionshinder och hälsa (ICF) i 19 kategorier i domänen omgivningsfaktorer. Som underlättande faktorer framträder bl.a. tillgång till hjälpmedel, en fysisk miljö tillgänglig för aktiviteter samt att få stöd från närstående, vänner och personal i hälso- och sjukvård och omsorg. I resultatet framkom betydelsen av ett empatiskt förhållningssätt när personal möter den äldre personen i dennes hem. Resultatet indikerar att hemrehabilitering inte till fullo tillgodoser äldres behov av rehabilitering. I studie IV framkommer personliga faktorer som inre styrka, motivation, engagemang och tålamod för att nå positiva resultat i en rehabilitering som sträcker sig över flera år. Rehabilitering beskrivs i fysiska och psykiska faser som övergick i att hantera en fysisk funktionsnedsättning med svårigheter att gå i dagligt liv. Resultatet visar på betydelsen av adekvat information, vikten av socialt stöd och tillgänglighet till hälso- och sjukvårdspersonal under rehabiliteringsprocessen.Avhandlingen bidrar till en ökad kunskap om hur multidisciplinära team, äldre personer och familjemedlemmar upplever rehabilitering i hemmiljö. Nyttan med avhandlingen kan medföra att hemrehabilitering som vårdform kan bli föremål för diskussioner om hur det utformas och organiseras för att på bästa sätt stödja de äldre och närstående med utgångspunkt från de äldres och närståendes erfarenheter och upplevelser. Detta kan ses gagna deltagarna på individnivå men även för utveckling inom yrkesprofessionen. Avhandlingen har även visat på möjligheten att implementera ICF i rehabiliterande omvårdnad.
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15. |
- Blusi, Madeleine, 1968-
(författare)
-
E-health and information- and communication technology (ICT) as support systems for older family caregivers in rural areas
- 2014
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall objective of the thesis was to investigate how older family caregivers in rural areas experienced participation in an e-health based caregiver support system. Participants were 95 caregivers allocated to intervention group (n=63) and control group (n=32). The thesis had a mixed method design and is based on four original articles (I-IV). Data was collected through web-camera interviews (I-III), telephone interviews (II,IV) and questionnaires (II,IV) after 1.5 years of using e-health support. Quantitative data was analyzed using comparative statistics, multiple linear regression and logistic regression. Qualitative data was analyzed with content analysis. Article I showed that the caregivers, despite lacking experience from using computers, were able to adopt the new technology, with help from support nurses and family. Caregivers felt e-health helped them to regain social inclusion. Article II had a comparative design, comparing e-health support with conventional caregiver support. Caregivers using e-health were more satisfied with their support and found it to be available, flexible and helping them enhance caregiver competence. Control group caregivers were less satisfied with support and experienced unmet needs. Article III showed that e-health can reduce caregivers’ feelings of isolation. Two themes were created, Expanding the concept of place and Developing networks. Article IV revealed that caregivers used e-health frequently, experienced benefits from using it and had become more independent. Support nurses were disappointed about the decrease in contact with caregivers, and also acknowledged a need for developing the professional nursing role while working with e-health. Conclusions drawn from the findings were that participants experienced benefits from e-health support and it helped them become more independent. Swedish municipalities are obliged to provide caregiver support, the findings from the study are valid to conclude that e-health support are as good as, or even more effective, than conventional support for older family caregivers in rural areas.
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16. |
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17. |
- Brouder, Patrick
(författare)
-
Tourism Development in Peripheral Areas : Processes of Local Innovation and Change in Northern Sweden
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Tourism has reached almost all regions of the world and has had a notable growth in the peripheral regions of Europe. Attempts at tourism development in rural and peripheral areas have resulted in widely varying outcomes and have often been undertaken as a last resort by communities. Despite mixed results, tourism persists as a tool for regional development. There has not been so much research on the evolving nature of tourism entrepreneurship in regions where tourism is relatively new as a commercial/entrepreneurial activity, e.g., the rural and peripheral north of Europe. This thesis presents Northern Sweden as a regional case study but it is reasonable to assume that the research results are transferable to similar regions with a similar range of nature-based tourism in small communities. The results show that tourism stakeholders co-evolve over time even though formal networks are loose and project-based (Article 1). Tourism firm survival improves for entrepreneurs with previous related experience but there is not necessarily an outsider advantage and new tourism firms contribute to job creation despite high rates of attrition (Article II). Protected areas with unique attributes (e.g., Laponia) can attract distant entrepreneurs but must manage these stakeholders more proactively (Article III). Climate change is a long-term challenge with firms not needing to adapt yet but facing differing exposures dependent on location and firm mobility (Article IV). Finally, evolutionary economic geography helps to better understand the processes of change in tourism in rural and peripheral areas (Article V).
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18. |
- Bång, Joakim
(författare)
-
Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). Both pheromones and allelochemicals can be used as environmentally friendly pest management. Many semiochemicals, i.e. behaviour modifying chemicals, consist of pure or well-defined mixtures of stereoisomers, where some of the other stereoisomers can be repellent. It is therefore important to be able to separate them to produce a synthetic pheromone in a mixture that is attractive.Pine sawflies are a family of insects that in some cases can be severe defoliators of conifer trees. Diprion pini, Diprion similis and Neodiprion sertifer are severe pests for these trees and have got the most attention in pine sawfly pheromone studies. The pheromone precursors are stored in the female body as long-chain secondary alcohols, which, when released, are esterified to acetates or propionates. The alcohols are chiral, and normally one of the stereoisomer is the main pheromone component, sometimes possible together with other stereoisomers as essential minor components.Bicyclus is a genus of African butterflies, and especially Bicyclus anynana has become a popular model for the study of life history evolution, morphology, mating choice and genetics. The wing pattern of Bicyclus differs depending on the season, with large eyespots during the rain-season and small or absent spots during the dry season. Euglossa is one of the genera among the orchid bees in the Neotropics that does not produce its own pheromone. Instead, the males collect fragrances from orchids and other sources and store them in a pocket in their hind legs. Both Bicyclus and Euglossa use semiochemicals similar to pine sawflies, and thus can be analysed by the same methods.Pheromones and other semiochemicals in insects are often present in low amounts in a complex matrix, and purification of the sample before chemical analysis is often required. A common method is gradient elution on a solid phase silica column. Separation of stereoisomers can be achieved either by using a column with a chiral stationary phase (CSP) or with pre-column derivatisation using a column with an achiral stationary phase (ASP) or a combination of both, with mass detection as the dominant detection method. The purpose of this work has been to improve the purification method, find suitable methods to separate the stereoisomers of secondary alcohols, and to apply this on extracts of insects.By selecting the right fractions to collect during gradient elution the purification method was optimised. To reduce plasticizer contamination from ordinary columns, solid phase columns of Teflon or glass were used. For pre-column derivatisation of different chiral alcohols various acid chlorides were tested. For the pine sawfly pheromone precursors enantiopure (2S)-2-acetoxypropionyl chloride was the best choice. To separate some of the stereoisomers achiral 2-naphthoyl chloride was used. For derivatisation of 6,10,14-trimethylpentadecan-2-ol (R)-trans-chrysanthemoyl chloride was the best choice. The derivatised alcohols were separated on different columns, both chiral and non-chiral. Varian FactorFour VF-23ms was chosen as a general-purpose column, the Agilent HP-88 column was the best column with an ASP of those tested, and the Chiraldex B-PA column (CSP) was the only one that could separate all eight stereoisomers of derivatised 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol.To determine the stereoisomeric purity of standard solutions used in field experiments and extracts of different species of insects the optimised methods were applied. For extracts from B. anynana, Euglossa and Neodiprion lecontei this work describe the first determination of the stereochemistry of some of their semiochemicals.For the determination of the stereochemistry of chiral semiochemicals the methods for purification and separation presented herein have shown to be of great value. The results will hopefully contribute to a better understanding of the communication among insects, and ultimately to a more environmentally friendly pest control.
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19. |
- Bäckström, Britt
(författare)
-
En tillvaro av utanförskap : En longitudinell studie om att vara i medelåldern och närstående till en person som insjuknat i stroke
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Ett övergripande syfte med avhandling var att belysa den levda erfarenheten av att vara i medelåldern och närstående till en person som insjuknat i stroke för första gången och studera de närståendes erfarenheter av förändringen över tid under det första året efter utskrivning till hemmet, samt att belysa innebörden av medelålders makars levda erfarenhet av relationen till en partner som insjuknat i stroke; under det första året. Avhandlingen omfattar 4 delstudier (I-IV) som sammantaget utgör en longitudinell studie. Tio närstående (40 - 64 år) till personer insjuknade i stroke (förstagångs insjuknande) med förväntat hjälpbehov överstigande 6 månader, inkluderades konsekutivt i studien och följdes under ett år efter utskrivning till hemmet. Narrativa intervjuer utfördes en månad (I, n=10), sex månader (II, n=9) och ett år (III, n=9) efter utskrivning till hemmet. Bland de närstående i delstudie I-III fanns fyra kvinnliga makar (gifta; n=2, sambo; n=2) som utgjorde deltagarna i delstudie IV. För att analysera data användes en fenomenologisk hermeneutisk tolkningsmetod (I, IV) och kvalitativ innehållsanalys (II, III). Avhandlingen visar på att vara i medelåldern och närstående till en person som insjuknat i stroke, efter utskrivningen till hemmet, innebär att gå igenom en förändringsprocess i olika steg. Upplevelsen var att en månad efter utskrivningen kämpa för att inte tappa fotfästet i en otrygg livssituation, där de upplevde ett främlingskap inför situationen, sig själv och personen som insjuknat i stroke. Ändå svarade de närstående oreflekterat an ett krav på ansvar och omsorg (I, IV). Efter sex månader visade de närstående på en kamp för att integrera förändringarna orsakade av stroke till det dagliga livet, förlika sig med förlusterna och att hitta balans och en ny normalitet (II). Makarna förde en kamp för att återfå känslan av samhörighet med sin partner och hitta tillbaka till sin egen identitet som maka, vilket bara var möjligt i frånvaro av en vårdarroll (II, IV). Efter ett år tvingades de närstående att erkänna, lära sig hantera och förlika sig med förändringarna orsakade av strokeinsjuknandet (III). Makarna fick lämna en ‛bild‛ av hur deras partner en gång varit. En trygg relation i samvaro och jämlikhet med en känsla av ‛vi‛ förändrades och blev främmande och ojämlik och ersattes med en känsla av ‛jag‛ och ‛du‛. För att härda ut måste makarna omvärdera relationen till sin partner och målen i livet. Även om partnern fortfarande var i livet visade makarna en sorg och ett lidande beroende på förlusten av den relation de en gång haft till personen som insjuknat i stroke (IV). Avhandlingen visar även att de närstående inte upplevde sig varit sedda och bekräftade av den professionella vårdpersonalen i sin egen situation som närstående. Vårdens fokus upplevdes hela tiden enbart vara den sjuke och främst de fysiska förändringarna hos personen med stroke. De närståendes upplevelse var av oförståelse för innebörden av de kognitiva och emotionella förändringarna hos den sjuke (I, II, III). De närstående gav så småningom också upp sin strävan att bli bekräftade vilket innebar att bära på ett lidande som inte blev synliggjort (III). En annan del av förändringsprocessen var att de närstående gick ifrån självförnekelse med fokus på den som insjuknat och nuet (I), till en medvetenhet om att ta egna behov i beaktande (II) och att även fokusera på eget välbefinnande för att orka i en framtid (III). Avhandlingen visar att de medelålders närstående går igenom en transitionsprocess, där upplevelser av förluster, förändringar, lidande och sorg finns relaterat till; dåtid, nutid och framtid. De närståendes upplevelse av oförståelse och brist på känsla av bekräftelse i deras livssituation under året efter utskrivningen till hemmet, kan leda till en känsla av ensamhet och övergivenhet både inom de närstående själva, men också i förhållande till andra och världen utanför.
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20. |
- Carlerby, Heidi, 1967-
(författare)
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Health and Social Determinants Among Boys and Girls in Sweden : Focusing on Parental Background
- 2012
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The majority of Swedish boys and girls have good psychosomatic health. Despite that the risk of mental health problems such as nervousness, feeling low and sleeping difficulties has increased steadily in recent decades. Moreover, previous surveys on health and well-being indicate that boys and girls of foreign extraction in Sweden are at increased risk of ill health compared to boys and girls of Swedish background. The main aim of this thesis was to analyse health and social determinants among boys and girls of foreign extraction in Sweden. The factors explored in papers I–IV include parental background, family affluence and gender and their associations with subjective health complaints, psychosomatic problems or health risk behaviours. Other included risk factors for ill health were involvement in bullying, low participation and discrimination at school. This thesis takes an intersectional perspective, with ambitions to be able to emphasize the interplay between different power relations (i.e. gender, social class and parental background). Two sets of cross-sectional data were used. Three papers were based on the Swedish part of the World Health Organization’s Health Behaviour in School-Aged Children. The sample consisted of 11,972 children (boys n = 6054; girls n = 5918) in grades five, seven and nine from the measurement years 1997/98, 2001/02 and 2005/06. The response rate varied between 85 and 90%. About one fifth of the included children were of foreign extraction. For the fourth paper regional data from Northern Sweden were used. Boys (n = 729) and girls (n = 798) in grades six to nine answered a questionnaire in 2011 and the response rate was 80%. About 14% of the included children were of foreign extraction. Statistical methods used were chi-square test, correlation analyses, logistic regression analyses, cluster analyses and test of mediating factor. The results showed that girls of foreign background were at increased risk of subjective health complaints (SHC) and boys of mixed background were at increased risk of psychosomatic problems (PSP). Increased risk of allocation to the cluster profile of multiple risk behaviour was shown in boys and girls of mixed background, in girls of foreign background and in girls of low family affluence. Increased risk of allocation to the cluster profile of inadequate tooth brushing was shown in boys and girls of foreign background and in girls of low family affluence. General risk factors for increased risk of ill health for boys and girls in Sweden were: any form of bullying involvement, low family affluence, low participation and discrimination at school, of which the latter also was a mediating factor for ill health. Living with a single parent was a risk factor for ill health among girls. The results can function as a basis for developing health promotion programmes at schools that focus on social consequences of foreign extraction, family affluence, participation as well as health risk behaviours and gender.
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21. |
- Carlsson, Fredrik, 1974-
(författare)
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Wood Fungi and Forest Fire
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Forest fires have been the major stand-replacing/modifying disturbance in boreal forests. To adapt to fire disturbance, different strategies have evolved. This thesis focuses on wood fungi, and the effect of forest fire on this organism group. In many ways it is a study on adaptation to forest fire, in concurrence with adaptation to dry open habitats. In Paper I we study increased heat resistance in mycelia from species prevalent in fire prone environments. Fungi were cultivated on fresh wood and exposed to different temperatures. Species prevalent in fire affected habitats had a much higher survival rate over all combinations of time and temperature compared to species associated with other environments. Based on this results the competitiveness was tested after temperature stress (paper II), three fire associated species, were tested against three non fire associated species. All fire associated species had a clear advantage after heat treatment, conquering a larger volume of wood than its competitor. In paper III we studied the effect of heat shock on decomposition rate, 18 species was tested. Species were cultivated and monitored for CO2 accumulation for 8 weeks and then heat shocked. All species including non fire associated species seemed to up-regulate decomposition after heat shock, this response was more pronounced in fire associated species. To look at the possible effect of forest fire on population structure (Paper IV), we developed 29 SNP/INDELs for Phlebiopsis. gigantea. We amplified the marker containing fragments in 132 individuals of P. gigantea in 6 populations, 3 which were found in areas affected by forest fire and 3 in unaffected areas. We found no genetic structure in accordance to forest fire. However we detected geographic structure, which stands in contrast to earlier studies. This might be due to the method, using SNP´s and number of individuals in the study. Finally we collected cross-sections of decayed logs to evaluate the number of fungal species domains that are likely to be hit when drilling a saw-dust sample in a log. We used these estimates to simulate how many species that will be found by a certain number of samples. We found that in 99% of the
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22. |
- Carlsund, Åsa, 1969-
(författare)
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Children`s Mental Health -with focus on family arrangements
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main aim of this thesis was to study children’s mental health with focus on family arrangements. The thesis was based on four studies (I-IV). Study number I, III and IV were quantitative studies with cross sectional design, using the Swedish version of Health behaviour in School- aged children (HBSC), including children aged 11, 13 and 15 years. The data was analysed with multiple linear regression analysis (I) and multivariate logistic regression analysis (III, IV). Study II was of qualitative descriptive design, based on 28 interviews with parents living in shared physical custody with their children. The qualitative study was analysed with inductive latent content analysis.Study I showed that lower levels of SHC and higher levels of SWB were associated with higher degrees of social capital in the family, school and neighbourhood. Social capital in family, school and neighbourhood had a cumulative influence on children’s SHC and SWB. In study II the participating parents described their own as well as the perceptions of their children and former partners. Parents’ perceptions changed from the beginning of shared physical custody, through the current situation, ending with perception of the future. The fifteen year old boys and girls (III) living in shared physical custody were more at risk of being a smoker or having been drunk compared with children living in two parent families. The results of sex <15 years and conduct problems showed that the risks didn’t differ significantly between these two groups. Study IV showed that children living in shared physical custody with their parents were more likely than children in two parent families to report multiple SHC, and low SWB. The variable of communication did not moderate the SHC and SWB of the children in any of these two groups.This thesis contribute with new and deeper understanding of the relatively new phenomenon: shared physical custody, and its associations to children’s mental health. The parent’s perceptions were an important complement to the children’s self reported health. In order to influence the decreasing mental health among children and adolescents, their opinions contributes to further understanding. Narratives from children, parents and practitioners are required in order to further study the association between children’s health outcomes and different family arrangements. Additional studies are needed to clarify how children’s mental health and different family arrangements are related to school, community economy, and society.
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23. |
- Cheng, Peng
(författare)
-
Applications of embedded sensors in loader crane positioning and rotor RPM measurement
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis, two novel applications involving embedded sensors arestudied, one dealing with loader crane positioning and the other involving rotorRevolutions Per Minute (RPM) measurement. The thesis presents a generalintroduction to the embedded sensor, its architecture and its use in mechanicalindustry, and provides the reader with an overview of conventional sensortechnologies within the fields of angle sensors and angular speed sensors, coveringtheir working principles, features, advantages and disadvantages and typicalapplications. The particular problems associated with the use of conventionalsensors in both loader crane positioning and rotor RPM measurement aredescribed and these problems provided the motivation for the designs of theembedded sensor systems developed in this thesis.In the case of the loader crane positioning, the origins of the project and thespecial requirements of the application are described in detail. In addition, apreliminary study is conducted in relation to the idea of a contactless joint angularsensor using MEMS inertial sensors in which four different methods, namely, theCommon-Mode-Rejection with Gyro Integration (CMRGI), Common-Mode-Rejection (CMR), Common-Mode-Rejection with Gyro Differentiation (CMRGD)and Distributed Common-Mode-Rejection (DCMR), are conceived, modeled andtested on a custom-designed prototype experimental setup. The results gatheredfrom these four methods are compared and analyzed in order to identify thedifferences in their performances. The methods, which proved to be suitable, arethen further tested using the prototype sensor setup on a loader crane and theperformance results are analyzed in order to make a decision in relation to the twomost suitable methods for the application of the loader crane positioning. Theresults suggested that the two most suitable were the CMRGD and the DCMR. Thepractical design issues relating to this sensor system are highlighted andsuggestions are made in the study. Additionally, possible future work for thisproject is also covered.In the first case for the rotor RPM measurement, the thesis presents themodeling and simulation of the stator-free RPM sensor idea using the Monte Carlomethod, which demonstrated the special features and performance of this sensor.The design aspects of the prototype sensor are described in detail and theprototype is tested on an experimental setup. The conclusions for the stator-freeRPM sensor are then made from the analysis of the experimental results and futurework in relation to this sensor is also proposed.In the second case of the rotor RPM measurement, the thesis presentsanother idea involving the laser mouse RPM sensor and the main focus of thestudy is on the performance characterization of the laser mouse sensor and theverification of the RPM sensor idea. Experiments are conducted using the test setup and results are gathered and analyzed and conclusions are drawn.Possibilities in relation to future work for this laser mouse RPM sensor are alsoprovided.The summary and the conclusion form the final chapter of the thesis andseveral important aspects of the designs relating to both the loader cranepositioning project and the rotor RPM measurement project are discussed.
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24. |
- Cronskär, Marie
(författare)
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On customization of orthopedic implants - from design and additive manufacturing to implementation
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This doctoral thesis is devoted to studying the possibilities of using additive manufacturing (AM) and design based on computed tomography (CT), for the production of patient-specific implants within orthopedic surgery, initially in a broad perspective and, in the second part of the thesis focusing on customized clavicle osteosynthesis plates. The main AM method used in the studies is the Electron Beam Melting (EBM) technology. Using AM, the parts are built up directly from 3D computer models, by melting or in other ways joining thin layers of material, layer by layer, to build up the part. Over the last 20 years, this fundamentally new way of manufacturing and the rapid development of software for digital 3D reconstruction of anatomical models from medical imaging, have opened up entirely new opportunities for the design and manufacturing of patient-specific implants. Based on the information in a computed tomography (CT) scan, both digital and physical models of the anatomy can be created and of implants that are customized based on the anatomical models. The main method used is a number of case studies performed, focusing on different parts of the production chain, from CT-scan to final implant, and with several aims: learning about the details of the different steps in the procedure, finding suitable applications, developing the method and trying it out. The first study was on customized hip stems, focusing on the EBM method and its special preconditions and possibilities. It was followed by a study of bone plates, designed to follow the patient-specific bone contour, in this case a tibia fracture including the whole production chain. Further, four cases of patient-specific plates for clavicle fracture fixation were performed in order to develop and evaluate the method. The plates fit towards the patient’s bone were tested in cooperation with an orthopedic surgeon at Östersund hospital. In parallel with the case studies, a method for finite element (FE) analysis of fixation plates placed on a clavicle bone was developed and used for the comparative strength analysis of different plates and plating methods. The loading on the clavicle bone in the FE model was defined on a muscle and ligament level using multibody musculoskeletal simulation for more realistic loading than in earlier similar studies. The initial studies (papers I and II) showed that the EBM method has great potential, both for the application of customized hip stems and bone plates; in certain conditions EBM manufacturing can contribute to significant cost reductions compared to conventional manufacturing methods due to material savings and savings in file preparation time. However, further work was needed in both of the application areas before implementation. The studies on the fracture fixation using patient-specific clavicle plates indicated that the method can facilitate the work for the surgeon both in the planning and in the operating room, with the potential of a smoother plate with a better fit and screw positioning tailored to the specific fracture (paper VI). However, a large clinical trial is required to investigate the clinical benefit of using patient-specific plates. The FE simulations showed similar stress distributions and displacements in the patient-specific plates and the commercial plates (papers III to VI). To summarize: the results of this thesis contribute to the area of digital design and AM in patient-specific implants with broad basis of knowledge regarding the technologies used and areas in which further work is needed for the implementation of the technology on a larger scale. Further, a method has been developed and initially evaluated for implementation in the area of clavicle fracture fixation, including an approach for comparing the strength of different clavicle plates.
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25. |
- Daghighi, Abtin, 1981-
(författare)
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Regularity and uniqueness-related properties of solutions with respect to locally integrable structures
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- We prove that a smooth generic embedded CR submanifold of C^n obeys the maximum principle for continuous CR functions if and only if it is weakly 1-concave. The proof of the maximum principle in the original manuscript has later been generalized to embedded weakly q-concave CR submanifolds of certain complex manifolds. We give a generalization of a known result regarding automatic smoothness of solutions to the homogeneous problem for the tangential CR vector fields given local holomorphic extension. This generalization ensures that a given locally integrable structure is hypocomplex at the origin if and only if it does not allow solutions near the origin which cannot be represented by a smooth function near the origin. We give a sufficient condition under which it holds true that if a smooth CR function f on a smooth generic embedded CR submanifold, M, of C^n, vanishes to infinite order along a C^infty-smooth curve gamma in M, then f vanishes on an M-neighborhood of gamma. We prove a local maximum principle for certain locally integrable structures.
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