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412 Uppsatser om Stem cell - Sida 4 av 28

Productivity of integrated harvesting of pulpwood and energy wood in first commercial thinnings

The aim of this study was to quantify the productivity and the costs of different harvesting systems (teams), containing harvesters equipped with accumulating harvester heads and forwarders, in first commercial thinnings were an integrated harvest of pulpwood and energy wood were performed. In the beginning the plan was to study and measure 20 sites before and after harvest. Due to storms during the summer of 2010, complete data could only be obtained from 8 of these 20 sites. Seven of these sites were privately owned and one was owned by UPM, all of the sites had been pre-commercially thinned. The mean stem density before harvest was 2578 stems per ha and the mean stem volume was 0.074 m3solid over bark.On average 1518 stems/ha was harvested.

Samband på individnivå mellan akuta klövskador och cellhalten i mjölk hos mjölkkor :

The purpose of the present study was to investigate the cow-level association between acute hoof lesions and the somatic milk cell count in dairy cattle. Cows from three loose-housed Swedish dairy herds were enrolled in the study if they had an acute hoof lesion treated by a veterinarian or professional hoof trimmer during the preceding year, according to farmer records. Studied lesions were sole ulcer, dermatitis, interdigital necrobacillosis and hoof abscess, in each case causing lameness. For each hoof-diseased cow, 0 to 3 healthy cows were included, matched with respect to herd, breed, parity and lactation stage. Cell counts were obtained from monthly test recordings from one month before to three months after the hoof-lesion diagnosis, and log-transformed.

Influence of prescribed burning and/or mechanical site preparation on stand stem density and growth of Scots pine stands above the Arctic Circle : results 9-19 years after stand establishment

Prescribed burning was commonly used for site preparation in Sweden to establish new forests until the 1960?s, when mechanical scarification was introduced. During recent decades the interest in prescribed burnings has increased again, mainly due to certifications of forestry stating that 5% of the regeneration areas should be burned on dry and mesic soils. The objective of the study was to evaluate actual influence of prescribed burning compared to other site preparation on stand stem density, growth parameters and tree damages for Scots pine (Pinus sylvestris L.) after direct seeding and planting. The study also attempts to simulate growth until first thinning.

Vederlagsgrundande mätning med skördare

This study was performed in collaboration with Moelven Skog AB, Örebro district. The purpose of the study was to review existing literature in order to describe the current status of harvester based measurement technology as the way to provide information for calculating payment to the forest owners. In addition to this, a short survey was conducted to find out how a switch to harvester based measurement would affect the administrative workload on timber purchasers working for the district. The literature study shows that the harvester measurement technology is ready to use if it is combined with well-established routines for control of the harvesters, methods for automatic quality indexing of the timber and ways of creating pricelists specially adapted for harvester measurement. Pricing each stem seems to be the most promising method. Stem pricing has several benefits.

Effektivisering och produktivitetsökning i produktionsflödet av Hammarhäftare på Isaberg Rapid AB

AbstractThe market?s demand to purchase more cost effective products is continuously increasing. The producers are forced to become more efficient and flexible with resources to produce high quality products at a low cost in order to maintain or increase market shares. With this in mind Isaberg Rapid AB is requesting a project to increase efficiency in the assembly cell of hammertackers. The company has found in Kaizen-events that there is a potential of efficiency improvements in the assembly group that has not been achieved.The objective with this paper is to identify the major factors that influence the efficiency in the assembly cell for hammertackers.

Utveckling av mobilapplikation

The company System Andersson is developing systems for controlling materials and production in industries. They want to add a new service, where parts of those systems are accessible through cell phones.In this paper we are investigating which technology are best suited for this kind of application. And then we describe how we are developing a prototype fort this application, based upon that technology. After investigating technologies such as Java ME, Microsoft Silverlight, and web applications we settled upon building the system as a web application, customized for a mobile environment.To build a web page which is readable by many different cell phones we use the markup-languages which are developed for cell phones. We put much effort in reading about the standards and recommendations for the mobile web, produced by the organizations W3C and OMA.

Augmented Reality i mobiltelefonen : En kunskapssammanställning med trafikinriktning

This master thesis is about Augmented Reality (AR), a phenomenon that has existed since the mid-fifties but only recently has become available for the general public. This report is a knowledge compilation about AR, focusing on AR in cell phones and the use of the technology in traffic related situations.AR is usually described as adding a digital layer of information onto the real world. There are different technologies to make virtual images; in cell phones sensor-based and camera-based technologies are the most common ones.In this report, the market of AR applications for cell phones has been investigated. Three use cases have also been investigated in order to get more knowledge about the designers' thoughts and visions.In order to analyze the technology and the applications in a broader and more scientific perspective, two theories has been used: Situation Awareness (SA) and the Service Dominant Logic (SDL). These theories seem useful when reflecting on the Swedish road administrations vision, and to investigate what the applications and the AR technology can contribute to the traffic domain.The conclusions of this thesis are that:- AR can be applied on most of the human senses, but augmenting by visualization is most common.- The market for cell phone applications is growing rapidly: AR applications are relatively new but on the rise.

Impulsmätning medelst gradvis deflektion av alla sprayer från högtrycks common rail spridare

A method for measuring the total impulse from a multi hole diesel injector, introduced inprevious thesis work, ?Development of a method and a device for measuring the momentumrate of fuel sprays?, by Mikael Lindström, has been further developed and tested. The conceptis to simultaneously deflect all sprays from a multi hole diesel injector by using a bell shapeddeflector. The fuel sprays are deflected straight down from their initial umbrella angle, andthe resulting deflection force is measured in a thin strained section of the load cell. The strainis given by three strain gauges, with quarter-bridge circuitry for each gauge.

Prion infection of ovine cell culture with a natural Swedish scrapie isolate from 1986

Scrapie is an infectious neurologic disease in sheep caused by prions, corresponding to transmissible spongiform encephalopathies (TSEs) in other species. The prion is presumably constituted of PrPSc, the misfolded form of the normal endogenous prion protein, PrPC, which is found in practically all cells in the body. PrPSc can induce a conformational change in PrPC and misfold it as an imprint of itself; this is how prions amplify and spread. The process of conformational change is poorly understood and there might exist intermediate forms between PrPC and PrPSc. Bioassay using mice has traditionally been the golden standard in prion studies but is limited by cost and time.

Förstudie för automatisering av gjutgodsrensning

This thesis work has been performed at the Division of Assembly Technology at Linköping University for a period of ten weeks. The work is part of the project ProFlexA, which is a research project in collaboration between Linköping University, Lund University, and industrial partners such as Combi Wear Parts and Smålands Stålgjuteri AB.The casting process creates random incurred burrs and defects, which must be removed during a cleaning process to make sure that the cast can be sold. Automation has long been sought for the cleaning of castings due to, among other things, poor working conditions for staff, but this has proved difficult to implement with today's technology. Automation has for some time been available for more capital strong companies with large annual volumes, but for smaller companies with small-and medium-sized volumes, automation has not been an option.The goal of ProFlexA is to develop an automated cleaning cell aimed at small-and medium-sized volumes.The goal of the thesis is to do a pre study at ProFlexA?s partners on cleaning of castings, and develop concepts for automated cleaning of castings.By recording the process and cycle times, the cleaning of castings has been documented as it works today, and on this basis, information and statistics has been compiled.

Forage production and summer use by ungulates on game fields and surrounding areas

Ungulates are causing conflicts between stakeholders due to browsing damage on forests and agricultural crops. At the same time there is a big demand of keeping high ungulate densities for sports hunting and recreational purposes. Movement patterns of ungulates are strongly correlated with forage availability. Therefore, measures affecting forage quantity and distribution might be a tool to reduce the economical losses in forestry without decreasing the ungulate densities and thereby decrease the conflict between different interest groups.This study investigated the potential biomass production and utilisation of marrow-stem kale (Brassica oleracea var. medullosa), at game fields in Misterhult, Sweden, as well as browsing effects on adjacent forests.

Etiska aspekter av preimplantatorisk genetisk diagnostik och genterapi

The research in the field of biotechnology is rapidly developing all over the world. Modern biotechnology offers unique opportunities, simultaneously as it gives rise to a number of ethical issues. Preimplantation genetic diagnosis (PGD), PGD/HLA (Human Leucocyte Antigen) and germline gene therapy (GLGT) are controversial techniques. PGD gives a possibility to identify a genetic disease prior to the embryo?s implantation in the uterus.

Skogsbränsledrivare i klen förstagallring med contorta

The aim for the study was to examine a harwarder´s (combined harvester-forwarder) productivity when harvesting forest fuel in first thinning stands that contains Lodgepole pine and calculate the economy of the harvesting work and estimate the quality of the thinning . The field study area where located near Arvån, about 15 kilometres south ?east from the city of Lycksele. The field studies were taken place in three different stands. All tree stands had the same tree age, but the tree species combination and the density varied.

Interactions between some plant-parasitic nematodes and Rhizoctonia solani in potato fields

The pathogenic fungus Rhizoctonia solani causes major economic losses for potato producers in Sweden. The producers, as well as advisors, have reported possible increases in severity of R. solani when free-living plant parasitic nematodes are present and active. There are several examples in the literature of interactions between pathogens where one, or both species, support or increase the damage made by the other organism. These complexes are important to investigate and to be able to forecast, since even low incidences of fungi or nematodes may result in an interaction of significance.

Stokastiska processer f?r modellering av cellpopulationer: Simulerad cell?ldrande och f?ryngring p? populationsniv?

I den h?r rapporten till?mpas tv? f?rgreningsprocesser, en diskret tid Galton-Watson och en kontinuerlig tid Markov f?rgreningsprocess, i syfte att studera hur en population av ?ldrande celler utvecklas beroende p? populationens celldelningsf?rm?ga och delningshastighet, d?r ?ldrandet ?r direkt kopplat till ackumulering av defekta proteiner. Vi kollar ?ven p? effekten hos cellens ?ldrande baserat p? hur k?nsliga de ?r f?r defekta proteiner. Populationens delningsf?rm?ga har en avg?rande effekt p? hur v?l populationen v?xer och bibeh?ller ett l?gre antal defekta proteiner hos cellerna, med dessa f?ruts?ttningar ses ytterligare effekt baserat p? delnigshastigheten hos cellerna.

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