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81 Uppsatser om Organochlorine compounds - Sida 4 av 6

Återföring av växtnäringsämnen från avloppsvatten till åkermark : en bedömning av intresset för nya näringsrika produkter

Sewage sludge contains plant nutrients and has earlier been utilised as fertilizer to cropland. Unfortunately not only plant nutrients but also heavy metals, pathogens and organic contaminants tend to accumulate in sludge. The suitability to use sewage sludge in agriculture has therefore been subject to several discussions over the years. The Swedish food industry does no longer accept sludge as fertiliser for Swedish producers. In 1999 the Swedish parliament accepted several objectives for environmental protection. In order to prevent environmental pollution and further exploitation of the earth crust, one of these objectives confirm that phosphorous from sewage shall be recirculated to arable land.

Kan D-vitamintillskott minska depressiva symtom?

Background: Sweden is a country where vitamin D deficiency seems to be common, partly because of its geographical position, which reduces the availability of UVB radiation, but also that people avoid sunlight due to increased skin cancer risk. Research shows that vitamin D plays an important role in the prevention of many diseases such as cancer as well as autoimmune and neuropsychiatric diseases.Vitamin D is a fat soluble pre-hormone and a collective name for closely related compounds which act as hormones after undergoing a transformation in the body.Humans can utilize vitamin D through diet and produce it in the body by exposing the skin to the sun. Previous observational studies and epidemiological studies have established a hypothesis that there seems to be an association between vitamin D supplementation and reduction of depressive symptoms.Objective: The aim of this study was to investigate if vitamin D supplements may decrease depressive symptoms.Methods: This work is organized as a literature review and article search is made in the database PubMed in January 2012. Keywords used were ?vitamin D and depression? and inclusion criteria were: randomized clinical trials, be conducted on humans, written in English.

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Är den starkt växande vildsvinspopulationen ett hot mot tjäderns reden?

This case study is based on a previous documented method of manufacturing artificial nest containing pre-colored hen eggs. This method is going to be used to find, if the wild boar population, which is growing in number, is a threat to the capercaillie population.  In comparison to the wild boar population, the capercaillie population is diminishing in different parts of Sweden.  In order to find out if they are affect by each other, the case study was carried out during the months of April to May 2009. 100 artificial nests were placed out on various locations on the Södertuna estate just in the outskirts of Gnesta. The unique aspect of this study is that a fenced environment to keep out wild animals is used to conduct this study, which has been previously known to be free from wild boar, but the area outside has sittings of wild boar. So to fully understand how this affects the capercaillie population, 50 of the nests were placed outside the fence area, while the other 50 nests were placed inside the fenced area. The sites were visited on two separate occasions, and were noted of the changes inside and outside the fenced compounds.

Fermentation of lignocellulosic material by the alternative industrial ethanol yeast Dekkera bruxellensis

Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, aspen sawdust was used as lignocellulosic material.

Smaksatt vodka : En sensorisk analys av konsumenters preferenser

InledningÅr 1879, grundade Lars Olsson Smith Absolut rent brännvin, dåtidens Absolut Vodka. År 1979,hundra år senare passerade företaget en ny fas genom globalisering under varumärket AbsolutVodka. Sedan introduktionen av det nya varumärket har försäljningen stigit från 0,1 miljoner litertill 96,6 miljoner liter per år, över hela värden. Under senare delen av 1980-talet introduceradeföretaget smaksatta vodkasorter för att främja barbranschens cocktails.Syfte och frågeställningUppsatsens syfte är att kartlägga hur konsumenter upplever intensiteten på fem utvaldasmakegenskaper i smaksatt vodka, satt i relation till hur de egentligen önskar att intensiteten skullevara.Uppfyller Absolut Vodkas smaksatta vodkor konsumenternas preferenser?Metod och materialUndersökningen grundar sig i en sensorisk analys för att besvara uppsatsens syfte ochfrågeställning.

Patologiska förändringar och säsongsmässiga variationer i testiklar från svenska brunbjörnar (Ursus arctos) :

Functioning reproductive organs are essential for the survival of a species. The reproductive system is very sensitive to exposure of chemical substances of anthropogenic origin. Humans release great amounts of chemical substances to the environment by our means of life and these substances have been proved to have a negative effect on the reproductive ability of different vertebral classes. In the polar bear (Ursus maritimus) a declined reproductive ability as an effect of decreased testosterone levels and decreased testicular size has been connected to the presence of high levels of organohalogenic compounds like PCBs. Although the Swedish brown bear (Ursus arctos) is not as carnivorous as its close relative the polar bear it is still exposed to environmental.

Energy efficient storage of biomass at Vattenfall heat and power plants

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

Perioperativ omvårdnad vid kejsarsnitt hos tik ? förbättra utfall för tik och valpar

Dystocia, or difficult birth, is a commonly seen complication to natural birth in veterinary hospitals. Although other methods of resolving dystocia exist, 60 % of dystocias will need to undergo caesarean section. To perform a caesarean section, the bitch will have to undergo anesthesia. The purpose of this literary study was to provide a deeper understanding regarding how the physiologic changes that occur during pregnancy influence anesthetic management in the bitch and puppies. Which anesthetic drugs and drug combinations indicated was also investigated as well as how a veterinary nurse can optimize care of the mother throughout the procedure and how resuscitation of the puppies should be carried out for best possible outcome.

Anestesi vid kastration av spädgris :

An overwhelming majority of all male piglets are castrated without anaesthesia when they are very young. In Sweden this means that approximately one and a half million piglets are castrated every year. The reason the piglets are castrated is the strong and unpleasant smell and taste, the ?boar taint? that the meat from intact boars sometimes exhibits. Boar taint is chiefly cause by androstenone and skatole, two compounds that are mostly produced by sexually mature boars and are accumulated in the subcutaneous fat.

Olfactory responses of the parasitic wasp, Trybliographa rapae (Hymenoptera: Figitidae)

Delia flies (Diptera: Anthomyiidae) are economically important pests in several horticultural crops. The control is commonly relying on chemical insecticides, though there are possibilities with biological control from the natural enemies in the field. An important natural enemy is the parasitic wasp, Trybliographa rapae Westwood (Hymenoptera: Figitidae) that lays eggs in the Delia fly larvae. The parasitoid larva and the host larva have a parallel development until the host dies within its puparium and an adult parasitoid emerges. The aim of this thesis was to understand the attraction to host- and food-associated plant volatiles of T. rapae, in order to enhance the effectiveness of the parasitic wasp as a biological control agent.

Kvalitetssäkring av hushållsnära avloppsfraktioner : vad kräver livsmedelsbranschen?

On-site sewage systems are common on the countryside of Sweden with approximately one million on-site systems installed. Due to insufficient function, these contribute significantly to the total discharge of phosphorus to rivers and lakes, causing eutrophication. In order to reduce eutrophication and to fulfil one of the environmental quality objectives, the decision was taken by the Swedish Government in 2005 that 60 % of phosphorous in sewage sludge is to be recycled to arable land before 2015. To make recycling a reality, new solutions have to be found. Federation of Swedish Farmers (LRF) takes an active interest in this issue and has initiated this study. One problem is that the food industry is sceptical towards recirculation due to the risks that products from sewage systems may contain pathogens, heavy metals and unwanted chemical compounds, e.g.

Antibiotic resistance associated with bacteria in irrigation water : a case study of irrigation ponds in Southern Sweden

The focus of this project was to characterize the occurrence of ESBL-­?producing bacteria in two irrigation water ponds in Southern Sweden. Samples were taken from two ponds nearby each other, from which analyses were made based on levels of community and individual isolates. Community samples were used for attempts for characterization of resistance patterns in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade. in irrigation water using the Omnilog PM-­?plate system. The growth of community microbiota in the presence of the following antibiotic substances was assessed; amikacin, gentamicin, kanamycin, penicillin G, ampicillin, piperacillin, trimethoprim, potassium tellurite and ciprofloxacin. Isolates were pure cultured using semi-­?selective media: LB, Rainbow Agar, mEnterococcus, 0.1 TSA and VRBD. A total of 177 isolates were isolated randomly. Each isolate was identified using the Omnilog GENIII-­?system of biochemical characterization. Further, the isolates were tested on Brilliance ESBL-­?agar for their ability to grow. Out of the total number of isolates, 30 were selected, preferably Enterobacteriaceae or Pseudomonas spp., based on their high similarity to library strain during the identification in the Omnilog-­?system. These were further characterized using Etest-­?sticks. Three selected strains were picked for further analyses using exogenous isolation for attempts to simulate horizontal gene transfer, and Omnilog PM-­?panels containing various antibiotics of interest. Selections of samples were chosen for molecular tests targeting plasmid-­?borne resistance genes CTX-­?M1, CTX-­?M2 and SHV. The method for assessing community-­?resistance patterns showed ambiguous data that was difficult to interpret; further optimization is recommended. For all tested PM-­?plates, generally greatest differences between substances were found among wells with the strongest concentration of antibiotic substance. A total of 175 isolates displayed ability to grow on ESBL-­?agar. Etests confirmed ability of isolates to resist many ?-­?lactam antibiotics and many were clinically resistant to certain substances. No plasmids were transferred during exogenous isolation. During molecular tests, a few matches were found for the CTX-­?M1 gene. Isolates analyzed with Omnilog PM-­?plates showed resistance to most compounds tested. The isolates showed greatest resistance toward penicillin G, ampicillin, amikacin, kanamycin and trimethoprim. In the study, it was established that resistance among bacteria was frequently occurring in the irrigation water, and ?-­?lactamase producing bacteria was very common. Extended studies are needed to assess the frequency-­? and occurrence of horizontal gene transfer (HGF) in this environment. Although some potential corresponding data is found, it is at this point not possible to determine whether the resistances are due to antibiotics used in veterinary medicine, human medicine or one additional reason is travel and trade..

Rostfärgat slam i dränagesystem vid vattenkraftsanläggningar : orsaker och åtgärder

From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked. The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.

Tungmetaller i lakvatten : avskiljning med mineraliska filtermaterial

Four different kinds of filter-materials with reactive surfaces have been studied concerning their capacity to absorb heavy metals in leachate from a municipal waste deposit. The heavy metals studied were: lead, cadmium, copper, mercury, chromium, nickel and zinc. The leachate contains high levels of dissolved organic carbon (DOC) and has a high pH-value along with a high buffer capacity. These characteristics of the leachate make it difficult to remove pollutants and require efficient filters. The filters that were examined in the report are blast-furnace slag with CaO, sand covered with iron oxides, olivine and nepheline.

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