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81 Uppsatser om Extrusion deposition - Sida 5 av 6

Effect of liming and free Ca2+ on Cd uptake of carrots, Daucus carota

The level of cadmium (Cd) in Swedish arable land has increased during the last century and the average concentration of Cd in the plough layer is today 0.23 mg/kg. The increase is mainly due to anthropogenic activities such as phosphorus fertilizing, liming, import of feed, and atmospheric deposition from industrial emissions. Cadmium in the soil will be taken up by crops and is thereby transferred to humans via food. Carrot is one of the crops of concern, both because it may contain quite high Cd concentrations and due to the large consumption in Sweden. In the body, Cd is stored mainly in the liver and the kidneys and may cause several diseases already at low concentrations.

I vatten eller jord? : Nytolkning av depåfyndet från Eskelhem

In 1886 Hans Hildebrand received a Bronze Age hoard found in a field that belonged to Eskelhem´s rectory. A record was made where Hildebrand presented and documented the artifacts. The following year Oscar Montelius reviewed the artifacts, which he described as horse gears. He compared the horse gears with similar artifacts found in Europe that roughly had the same dating in order to trace the origin of the hoard.  Montelius conclusion was that the hoard was created on Gotland around 500 BC.

Amyloid beta inducerad klyvning av NG2 medierad via LRP-1 receptorn

Bakgrund: Deposition av fibrillär amyloid beta 1-42 (A?) i hjärnan är ett välkänt kännetecken för den neurodegenerativa sjukdomen Alzheimer?s (AD). Dessa ansamlingar påverkar pericyter, en celltyp involverad i blodkärlsfunktion och upprätthållande av blodhjärnbarriären (BBB). Pericyter uttrycker både receptorn low density lipoprotein receptor related protein 1 (LRP-1) till vilken A?1-42 binder, och proteoglykanet NG2.

Resultat av tjugofem års mätningar av Cs-137-halter i älg i Uppsala län

At the end of April 1986 reactor number 4 of the nuclear power plant at Chernobyl explod-ed and large amounts of radioactive particles were then released into the atmosphere due to both the explosion as well as the consecutive fire of the graphite core. A cloud of radioac-tivity was spread over the northern hemisphere, including Sweden, due to the prevailing wind directions. The radioactive particles were washed out from the cloud by rain and snowfall in some areas of Sweden and deposited on the ground. The deposited radionu-clides, primarily cesium and iodine isotopes, were later absorbed into the soil and taken up by the roots of the plants. Some of these radionuclides, like 137Cs, still persist in some of the terrestrial ecosystems at relatively high concentrations which lead to contamination of the meat of moose, roe deer and wild boar even today.The two municipalities Heby and Uppsala, in the eastern part of central Sweden, experi-enced a relatively large deposition of 137Cs which resulted in high levels of 137Cs in moose and other game.

Identifiering av områden med risk för fosforförluster genom ytavrinning : metodutveckling med GIS

The eutrophication of lakes and seas with the algal bloom and deficiency inoxygen that follow, has been given priority by the Swedish government as oneof 16 environmental objectives. The purpose of this project was to develop a toolbased on a simple model, limited amount of data and geographic informationsystem (GIS) to identify areas with risk for phosphorus losses due to surfacerunoff. This tool can act as a decision support to decide where appropriatemeasures should be applied with the aim of reducing phosphorus losses and bythat the eutrophication.The method that has been used is a combination of two models, one calculatingthe potential erosion while the other one identifies areas of erosion (net erosion)or deposition. This ability is of great importance because potential erosionshould be calculated on areas with net erosion. Areas with high potential erosionhave an increased risk for phosphorus losses due to surface runoff.The potential erosion was calculated based on factors which describe how topography(LS), land use (C), soil type (K) and precipitation (R) effect the erosion.All of them have been modified to a greater or lesser extent.

Intäktsredovisning - när i tiden och till vilket värde? : -En kvalitativ studie av fyra företags intäktredovisning.

Revenue is the largest post in the financial statements but is often least described. They are an important element when different companies are compared with each other. Revenue is often associated with assessment which Enron and Prosolvia is two examples of. Enron reported their incomes and assets while their costs and debts were not reported. Thus were a positive image maintained of the company when the financial position in reality were otherwise.

Nitrogen flow in Scania : substance flow analysis on a regional level

In this thesis, the flows of reactive nitrogen (Nr) in Scania were investigated and quantified. The thesis was also intended to form a basis for comparison between the urban nitrogen flow and other flows of nitrogen within Scania. The management of nitrogen in society has disturbed the natural nitrogen cycle. This is linked to a series of environmental problems such as eutrophication, acidification, global warming and smog. The method used was Substance Flow Analysis (SFA) for Nr. For calculation and flow charts Scania was divided into three subsystems; air, water and society.

Importance of epigenetics in animal breeding : genomic imprinting

ABSTRACTThe aim of this study was to give an overview of the evidence for genomic imprinting in livestock and other mammals as well as outline the potential use of gene imprinting in livestock breeding. Epigenetics is the mitotical and meiotical partial hereditary variation in genomic activity without any alterations of the DNA sequence. An example of epigenetic regulation is genomic imprinting where one allele?s expression differs depending on which parent it was inherited from. These parent-of-origin effects are currently overlooked in livestock production.

Bärbara datorer, en möjlig källa för nickel- och koboltexponering av hud? : Direktvisande tester för nickel och kobolt på bärbara datorer och frisättningsförsök på en bärbar dator

Background: Since1994, the EU NickelDirective is limiting the release of nickel from objects that are in prolongedcontact with skin. Despite this, nickel is still the most common cause of contactallergy in industrialized countries. This could implicate that other productswith short contact to the skin, which are not restricted by EU´s legislation inREACH (Registration, Evaluation, Authorisation and Restriction of Chemicalsubstances), could be a source of nickel or cobalt exposure. There is no limitfor cobalt release within REACH. To determine if there is cobalt or nickelpresent on the surface of a material and if metal can be released in contactwith the skin, there are quantitative and qualitative methods, such as the DMG(dimethylglyoxime)-test, the cobalt spot-test and a method for releasedetermination according to EN1811.Objectives: Laptops are not included in the REACH legislation.

Förändring av radiocesiumtillståndet i jordbruksgrödor i Gävleborgs, Västmanlands och Uppsala län efter Tjernobylolyckan samt en fallstudie med stallbalansberäkningar på en mjölkgård :

Several radioactive nuclides were deposited in Sweden after the Chernobyl accident in 1986. The greatest attention was given to 137Cs because of its relative long physical half life of about 30 years. 137Cs will be present in nature for more than 100 years before it has vanished completely. When radiocaesium decays to a stable end product ionizing radiation is emitted, which can cause cancer in humans that has been exposed to a high radiation dose. Radiocaesium behaves like potassium and is easily taken up into biological systems.

Är Lerbodaälven verkligen en problemälv? : undersökning av fosforhalter

Lerbodaälven is a river in the municipality of Kil which, due to high phosphorus content is not meeting the requirements for good ecological status according to the Water Framework Directive. The purpose of this report is to investigate the causes for the high content of phosphorus that has been measured in Lerbodaälven between 1995-2010. Four questions will be answered in this report. 1. Does the sewage treatment work affect the phosphorus level in Lerbodaälven? The result from the time series analysis shows that the sewage treatment works have a small impact on the phosphorus level in Lerbodaälven.

Utvärdering av lufthalts- och nedfallsmätningar gjorda vid Korsnäsverken : Samband mellan miljöförbättrande arbete i pappers- och massaindustrin och föroreningar i närområdet

En nedgång har setts i Sverige och Europa när det gäller luftföroreningar de senast årtiondena. Nedgången beror bland annat på minskade emissioner från industrier, övergång från uppvärmning med olje- och kolpannor till fjärrvärme och förbättrad bränslekvalitet. Denna studie utvärderar lufthalts- och nedfallsmätningar gjorda i närheten av pappers- och massaindustrin Korsnäs i Gävle. Mätserierna startar vid sent 1970-tal och går fram till årsskiftet 2009/2010. Nedfall av stoft, sulfat, natrium, kalcium och lufthalter av svaveldioxid samt sot studerades.

Källfördelningsanalys på delavrinningsnivå i Östergötland

Övergödning är ett av de största miljöproblemen i Östergötlands län. Övergödningsproblemet bottnar i en ökad tillförsel av kväve och fosfor från mänskliga aktiviteter till sjöar och vattendrag, vilket ger många negativa konsekvenser för bland annat den biologiska mångfalden. Syftet med detta examensarbete var att utföra en källfördelningsanalys för tre områden som inom olika övervakningsprogram uppvisat mycket höga eller extremt höga näringshalter. De tre avrinningsområden som behandlas är Svinstadsjön, Skenaån och Lillån (se karta i bilaga 3). En källfördelninganalys är en förteckning över, och analys av, vilka källor som bidrar till ett visst problem och med hur mycket varje källa bidrar till problemet.

Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites

The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value. Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.

Kvalitet i brödvete :

The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.

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