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412 Uppsatser om Stem cell - Sida 21 av 28
Produktivitet vid selektiv mekaniserad bioenergiröjning av eftersatta röjningsbestånd :
In Sweden, harvesting pre-commercial thinning (PCT) stems for energy purposes is a interesting way of financing the high cost of preparing dense stands for a profitable first conventional thinning. This concept can be labelled bioenergy thinning.
The aim of this study was to quantify the productivity of a Vimek 404R light harvester with an accumulating Naarva-Grip cutting head during the bioenergy thinning of a self-regenerated stand west of Sunnansjö in Dalarna. The stand was birch-dominated, contained 15 371 stems/ha, and measured on average 4,6 cm Dbh and 7 m tall. Even though the driver was well experienced with the machine, the stand in question was the first one that he ever thinned in this manner. Nevertheless, the driver strived to accumulate as many stems as possible during each crane cycle and chose to cut taller stems in half so as to make the handling and forwarding of the harvested stems easier.
Reducering av effektförbrukning i inbyggda system med Linux
Linux is a growing operating system in embedded systems. Today, Linux is not only in heavy servers but also in cell phones, PDAs, cameras and other devices running on battery power. While current technology is more energy efficient, more and more technologies are implemented into a single unit resulting in an overall increase of power consumption.Low power consumption is an increasingly important feature of a system today. Lower power consumption means lower costs, less environmental impact, and longer life for applications that runs on batteries.This work compiles methods to reduce power consumption of Linux systems. The work includes examining whether the available opportunities are platform-specific or of a more general nature.
En studie av elektronisk mobbning : Vilka kunskaper om och erfarenheter av elektronisk mobbning har flickor med språkstörning och autismspektra
The purpose of this study is to analyze the phenomenon of ?electronic bullying?, and furthermore to describe how this phenomenon is perceived by teenage girls with language disorders in combination with autism spectra. The conclusions and result from this study is derived from six in-depth interviews, thereof four being with girls with autism spectra diagnosis and all but one diagnosed with language disorder in addition (referred to as main respondents). The two reminding girls neither had language disorder nor autism spectra (referred to as comparing respondents). They were added to the study for the purpose of comparing their experiences and descriptions of those with language disorder and/or autism spectra diagnosis. For interpretation and analysis of study result, I have applied the method of phenomenology. The study?s main respondents had own experiences in the area of electronic bullying, albeit their level of knowledge of the subject were very limited and they had problems to interpret information given.
Yrkesroll i förändring? : En studie av ett antal statsanställda arkivariers upplevelser av införandet av en verksamhetsbaserad arkivredovisning
The aim of this thesis is to examine the archivist's professional role in public authorities and discuss if, and in what way, the profession is effected by the new swedish process oriented archival description system. The study focuses on swedish authorities and does not make any international comparisons with other institutions. Neither does it investigate archivists workingin the private sector, but centers on public institutions.The survey is performed in five swedish public authorities, using interviews and observations. Grounded theory is used as a method initially in the purpose of keeping an open mark towards the object of study. The initial results led on to questions about how well the archivists perceived that communication within the authorities served, and how this in turn prepossessed their work situation and the professional roles in which they found themselves.
Skogsskötsel för att minimera stormfällning över järnväg :
The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.
Structure and tree diversity of lowland limestone forest on Seram Island, Indonesia
There have previously been very few studies of forests on Seram Island in the Eastern Indonesian archipelago and none before on lowland limestone primary forests. The COLUPSIA project on collaborative land use planning has therefore chosen Seram as one of two project sites. The objective of the COLUPSIA project is to establish collaborative and equitable land use planning. In order to achieve its objective the COLUPSIA project aims to improve understanding of traditional resource management and how it interacts with governmental systems, as well as enhancing knowledge about tropical landscapes and ecosystem services.The aim of this study was to contribute to the COLUPSIA project through describing lowland limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life forms and environmental data.
Histonmodifieringar och alternativ splicing
Alternativ splicing av pre-mRNA ger upphov till proteindiversitet. Histonmodifieringar kopplas till den alternativa splicingens reglering genom adaptorsystem som overfor den epigenetiska informationen direkt till splicingfaktorerna. De cis- agerande RNA- elementen pa exoner och introner med tillhorande trans- reglerande splicingfaktorer paverkas darfor direkt av specifika histonmodifieringar. En sammankopplande integrerad modell over en rad DNA- baserade processer foreslas. Denna komplexa modell ger en bild av interaktioner och paverkan mellan dessa delar.
Metsä-Serla, Norske Skog och Södra Cell : ägarstrukturer i förädlingsföretag till skogsägarföreningar
Inom skogsnäringen sker idag en omfattande strukturomvandling. Från att ha varit en fragmenterad bransch med många små aktörer går nu företagen samman i internationella koncerner. Bland kooperativa företag sker även en utveckling mot alternativa former av kooperativa företag. Dessa bildas för att bättre möta omvärldens krav. Bland annat ägar-strukturen är under förändring genom att externa ägare bjuds in i olika utsträckning.
Bestämning av utfallet av translokationen t(11;18)(q21;q21) hos patienter med MALT-lymfom genom FISH analys
Lymphoma is a group of malignant tumour diseases developing in the secondary lymphatic system. These diseases can develop in all organs as lymphocytes are ubiquitously in the body. In connection to mucus membranes we find mucosa-associated lymphoid tissue, MALT, in which lymphoma can spontaneously but slowly develop, mostly at chronic inflammation or at autoimmune diseases. Today these diseases are incureable with the exception of some cases caused by Helicobacter pylori-infection. Antibiotic treatment of these cases can induce remissions.MALT-lymphomas have characteristic histological and molecular properties.
Produktion av single cell protein från restströmmar från 2:a generationens bioetanolproduktion
Rapporten ingår i ett FoU- projekt för Högskolan Dalarna, där målet är att ta fram en konstruktion utan ångspärr som ska klara dagens mått på lufttäthet och fuktkrav.Syftet med denna rapport är att utreda hur fukt påverkar en byggnad medmassivträstomme och olika isoleringsmaterial utan ångspärr. Mineralull och träfiberisolering jämförs mot varandra för att se hur dessa påverkarfuktbelastningen i en väggkonstruktion. Testobjektet är lokaliserat i Dalarna, inget fukttillskott har funnits inomhus i byggnaden.För att genomföra detta arbete har tre stycken olika metoder används. Ensimulering, verkliga uppmätta värden och en provtagning. Fuktsimuleringen genomfördes med hjälp av programmet WUFI, uppmätta värden i form av relativ fuktighet och temperatur har samlats in kontinuerligt under två års tid från väggkonstruktionen via mätsensorer.
Från digitalt till analogt : En kvalitativ studie av överföringsprocesserna från MIDI till notskrift i symfonisk musik
This study examines how to translate digitally composed symphonic music to note script and how it gets readable and playable. With the help of professional musicians from the Norrköping Symphony Orchestra, teachers from Kulturskolan in Norrköping as well as other musicians, I have learned how I can improve each individual stem in my composition. I also learned how to write for a real musician. My score have been analyzed by composers and a conductor which have given me a more in depth insight into composing symphonic music.The theory section describes important MIDI aspects, score preparation and note editing techniques. Thereafter is a section about the symphony orchestra and its instruments? history and how the situation is today.
Lodgepole pine - stability after thinning
SCA has today almost 300 000 hectares of their forest land planted with lodgepole pine(Pinus contorta var. latifolia). Due to initial extensive planting in the 1970ies the area oflodgepole pine forests in the thinning age has grown rapidly from the end of the 1990ies.During the years 1996-2005 first commercial thinning of lodgepole pine at SCA took place.The goal of the hereby presented study was to investigate the growth and stability in thosefirstly-thinned lodgepole pine stands a few years after thinning. Furthermore, the objectivewas to investigate the relationship between stand stability and different stand parameters.Additionally, lodgepole pine stem quality was estimated.The study is mainly based on the data collected during an inventory project carried out atSCA in 2008. Altogether 91 lodgepole pine stands in northern Sweden were measured afterthe first thinning.
Matrismodellen vs Two-part regressionsmodeller - effekter på Region Skånes resursfördelning
An important task for Region Skåne is to allocate resources to the health care districts. From 1999 to 2002 Region Skåne used needs-based resource allocation as a model for allocating resources. In a needs-based resource allocation individuals with the same socioeconomic and demographic characteristics are assumed to have the same level of need and are therefore allocated the same amount of resources. During the period of needs-based resource allocation a matrix model was used as a method. In the matrix model individuals were divided into cells after each combination of the socioeconomic and demographic variables.
Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering
Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.
Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring
The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.