ABSTRACT Tobacco Rattle Virus (TRV) is a soilborne plant virus. It is an important pathogen in potatoes where it causes spraing disease. This disease can lead to significant economical loss for the farmer, so it is imperative to get the proper diagnose before planting. TRV is spread naturally by free-living nematodes (Trichodorus and Paratrichodorus). Transference of TRV to a plant occurs when the virus-carrying nematodes feed on plant roots. The relationship between virus, nematodes and plants is complicated, and has to these days not been fully characterized. The diagnostic methods available today do not work sufficiently.

The cattle production in the world has been questioned in Sweden due to its negative impacts on the environment. The use of imported soya bean meal as a protein feed for Swedish cattle results in the cutting of rainforest and an extensive use of pesticides in the countries were the soya beans are produced. As a consequence, the environmental impacts caused by cattle production increases. A production of protein feeds in Sweden would decrease the transportations and the cutting of rainforest. For organic beef producers the possibility to produce home-grown protein feeds is important since organic protein feeds can be difficult to obtain in another way.

Anlagda våtmarker i avrinningsområden från jordbruksmarker mottar ofta vatten med höga halter av partikelbunden fosfor. Den viktigaste processen för avskiljning av inkommande partikelbunden fosfor är sedimentation. Resuspension är en process som motverkar netto-sedimentationen av partiklar och kan således minska våtmarkers förmåga att hålla kvar fosfor. Syftet med den här studien var att undersöka om A. aquaticus påverkar resuspensionen av partiklar, och om större tätheter av A.

Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.

Fosfor (P) är ofta det begränsande ämnet i akvatiska system och kan i höga mängder bidra till övergödning i sjöar och hav. För att minska tillförseln av partikelbunden fosfor som läcker från jordbruksmark kan våtmarker anläggas i avrinningsområdet. För en effektiv avskiljning är det viktigt att partiklar sedimenterar i våtmarken och stannar i sedimentet. Studier har visat att vissa karpfiskar och märlkräftor genom bioturbation kan orsaka resuspension av partiklar, samt att effekten ökar med ökad täthet. Syftet med denna studie var att undersöka om även makroevertebraten Asellus aquaticus (sötvattensgråsugga) kan orsaka resuspension av partiklar.

The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated.

Manure evaluation has been suggested as a cheap, fast and easy method which can give information about the digestibility of the ration, the function of the rumen, where in the gastrointestinal tract the feed is digested and the health of the cow. An experiment was conducted to study how manure evaluation could be used as a management tool in Swedish Dairy farming. Manure was collected from cows on Kungsängen Research Station and from 9 other farms. The manure samples were analysed for dry matter, ash, starch, pH-value and particle size (wet sieved). Also, the consistency of the manure was determined on a 5-point scale and the colour and smell were noticed. Penn State Forage Particle Separator was used for determining the particle size of the roughage.

The main purpose of the project was to identify potential environmentally harmful substances which can be leached from rubber asphalt. A method for analysing asphalt was developed and three rubber asphalt materials were analysed after being cryogrinded. One of the materials was also tested in a road machine made for testing of asphalt paving. The particles created in the machine were analysed in the same manner as the cryogrinded asphalt materials.The asphalt materials were leached by water during 24 hours. The leachates were extracted with dichloromethane, dried with sodium sulphate and concentrated to a small volume.

Flertalet studier har påvisat ett samband mellan koncentrationen av partiklar ? 10µm i luftföroreningar och cardiovaskulär- och pulmonell morbiditet och mortalitet. Vid resektion, koagulering/bränning med diatermipenna under operationer alstras rök. Denna rök innehåller bland annat mutagena och carcinogena partiklar i inhalerbar storlek (partiklar ? 10µm).Ett första syfte med denna studie var att kvantifiera den mängd ultra-fina partiklar (UFP) och partiklar ? 10µm som operationspersonal exponeras för i operationsrummet, vid användande av diatermi med mobilt rökutsug.

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

On ocean beds around the world sinking particles of residual biomass from animals and vegetation have, over time, accumulated into thick layers of sediment. For researchers these layers of sediment contain valuable information about the earth?s past climate, information that can be used to predict future climate change and to estimate natural vs. human causes of today?s global warming.The Institute of Geosciences at Stockholm University studies sediment cores that have been acquired with an apparatus called piston corer.

That air pollutants of different kind has impact on our climate can hardly haveavoided anyone during the past years environment explosion in the media. But howis it actually with the reverse, i. e. the climate's impact on air pollutants? The aimwith our degree thesis is to try to find out if different weather factors, statisticallyseen, promotes atmospheric pollutants and particles in the air and vice versa.We got access to data on air pollutants and weather factors that was registeredduring year 2007 at Femmanhusets air pollutant and weather station in Gothenburg.In order to do a statistical investigation of these data, and to be able to analyze if itoccurs relations of various kind, we used the statistics program SPSS.

ABSTRACTIntroduction: Postoperative wound infection is the third most common nosocomial infection in Sweden. The ever-growing problem of antibiotic resistance provides surgical departments a big challenge when it comes to preventing the spread of infection. Operating theatre nurses have a vital role in the prevention of infection. In addition, correct ventilation in the operating theatre is of great importance. The caregiver is responsible for quality assurance of ventilation in the operating theatre, but the work can be delegated to other staff within the department.

In studies of serum, in the early 1930s, from patients with pneumonia, a factor was found. It could agglutinate certain pneumococcal species. This factor, which later became known as C-reactive protein (CRP), increased sharply during the early and middle stages of the disease. CRP was identified as an acute phase protein and found especially in bacterial infections. CRP is synthesized in the liver by stimulation of interleukin 6 (IL-6), which is produced by the monocytes, and consists of five non-covalently bound subunits.The aim of this study was to compare two different analytical instruments (Vitros 5.1 FS Ortho-Clinical Diagnostics and QuikRead CRP Orion Diagnostica) for CRP analysis.

Headwater streams are affected by anthropogenic impacts at multiple scales. One aspect of human impact is sediment transport associated to the abundance of stream structures as large woody debris and the composition of the riparian zone from forest to agricultural landscapes. Riparian buffer zones and stream structures like dead wood are considered as generally important structures for protection against an increasing amount of sediment particles in the water. Hence, in this study these structures were quantified in thirty different stream segments on land and in the water. To measure the transport of sediment Whitlock-Vibert boxes were used in three different types of landscapes; forest, transition and fields. The boxes were left in the stream segments for three months, the taken up and dried and weighed. The results showed that the transition-land in Frösvidalsån had the highest sediment transport. The second highest transport of sediment was in Blackstaån at the fields.