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528 Uppsatser om Concentrations difficulty - Sida 6 av 36

Årstidsdynamik för kvicksilver i ett sövattensediment :

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Vuxna personers upplevelser av att leva med funktionsnedsättningen ADHD : - en självbiografistudie

Background·ADHD  is a syndrome characterized by attention deficits, difficulty of concentration, restlessness and lack of control. The number of persons diagnosed with ADBD have increased over the past few years. One reason for the increase is believed to be that the knowledge has increased in recent years and more persons can be diagnosed . As a nurse it is important to know about ADHD and how it affects the persons with it.Aim. The purpose of this autobiography study was to describe the experience of adult persons living with the disability ADHD.Method.

Fördjupad miljöriskbedömning av förorenade markekologiska system. : Integrering av kemisk, toxikologisk och ekologisk information.

AbstractThe research project Liberation, supported by the European Commission under the Environment and Sustainable Development Programme (Fifth RTD Framework Programme) aimed at developing a decision support system for ecological risk assessment of contaminated sites has proposed a tiered system including the triad method. This method integrates contaminant chemistry and bioavailability analyses with observed ecotoxicological effects in soil and groundwater. In this study the triad method was used to perform a risk characterization of a former surface treatment and metal industry, now used for the student union buildings of the Mälardalen University in Eskilstuna, Sweden. On the site, high concentrations of copper, zinc and nickel have been detected in the soil in a preliminary investigation of contaminant levels with XRF. For performing the risk assessment of the site according to the triad method, contaminant bioavailability, soil metal concentrations and soil toxicity were determined and an ecological assessment was carried out on four selected soil samples (one reference soil and three samples with low (B), medium (C) and high (D) contaminant levels). Contaminant bioavailability was measured through leaching (ISO TC 190/S7) and biouptake tests (DGT).

Utvärdering av GnRH-stimulering som en metod att avgöra om en honkatt med okänd historik är kastrerad :

This study has been made to evaluate if there is a significant difference between non-estral intact versus ovariohysterectomized queens in their production of estradiol after exogenous gonadotrophin-releasing hormone stimulation. The purpose is to find a tool, which can help to diagnose if a free-roaming queen is already ovariohysterectomized or not. There are also other situations where this tool could be useful, for example to diagnose the ovarian remnant syndrome. Previous studies in bitches have shown that GnRH-stimulation is an excellent tool to diagnose the presence of ovaries in the bitch. Eleven ovariohysterectomized and eleven intact queens have been included in this study where we have analyzed plasma estradiol and progesterone concentrations before and after a single intramuscular injection of the GnRH agonist buserelin (Receptal?).

Airtours : Slutet för begreppet kollektiv dominerande ställning?

Both the Commission and the Community Courts have on several occasions stated that a concentration that will cause the creation or strengthening of an oligopoly under certain circumstances might cause what?s referred to as a collective dominant position in the market. The concept of collective dominant position has gained a lot of criticism for being poorly defined and thereby create an uncertainty. The Commissions approach when applying the concept has also gained criticism for its lack of consistency. As a consequence of the Court of First Instances (CFI) decision in the case Airtours v.

Avsättningsmöjligheter för slaggrus från avfallsförbränning vid Åmotfors Energi

The incineration of waste is steadily increasing in Sweden and so is the production ofashes. The bottom ash has for many years been used as construction material inlandfills. Now many of the nation's landfills are closed and there is a great need to findanother beneficial use for the ash. Bottom ash is a gravel-like material and with itsmaterial properties it can replace natural gravel in parts of roads and surfaceconstructions. Today this use is only approved within landfill areas where leachate iscollected and checked.

En studie av hållbara alternativ till odlingstorv : - vid jordförbättring inom trädgård

Pharmaceuticals are environmental pollutants that are a major threat to aquatic ecosystems and very little is known about their ecological consequences. In this study growth, survival and behaviour (sociability, activity and boldness) of perch fry (Perca fluviatilis) were examined in order to study the possible effects of exposure to a benzodiazepine anxiolytic drug, Oxazepam, during embryonic development. The study tested following hypotheses: (1) perch growth is affected positively by exposure during embryonic development; (2) early perch survival is affected positively by exposure during embryonic development; and (3) boldness and activity increases while sociability decreases in perch fry exposed during embryonic development. Embryos of naturally spawned perch were exposed to water with two different concentrations of Oxazepam. The embryos were exposed during different parts (24-hour periods) of the embryonic development, because embryos may be more vulnerable at certain times during embryonic development and/or because the exposure at different times can produce different effects.

Quantitative thermal perception thresholds, comparison between methods

Skin temperature is detected through signals in unmyelinated C-fibers and thin myelinated A?-fibers in the peripheral and central nervous system. Disorders in thin nerve fibres are important and not rare but difficult to diagnose by the most common neurophysiological methods. In this pilot study different methods for quantitative sensory testing, QST, were compared to give some ideas about which method could be the most efficient to use in order to point out injuries of the sensory system in clinical practice. The comparison was made between Békésy (separate warmand cold thresholds) and Marstock test (combined warm and cold thresholds).

Avsättningsmöjligheter för slaggrus från avfallsförbränning vid Åmotfors Energi

The incineration of waste is steadily increasing in Sweden and so is the production of ashes. The bottom ash has for many years been used as construction material in landfills. Now many of the nation's landfills are closed and there is a great need to find another beneficial use for the ash. Bottom ash is a gravel-like material and with its material properties it can replace natural gravel in parts of roads and surface constructions. Today this use is only approved within landfill areas where leachate is collected and checked.

Interorganisatorisk styrning av leverantörsrelationer inom lågprismodebranschen: -En fallstudie av lågprismodeföretaget BikBok

This thesis concerns the control of outsourced interorganizational buyer-supplier relationships in the low-price fashion industry. A qualitative case study has been performed on two supplier relationships of a low-price fashion company. By identifying specificities of the industry and relating them to control problems and their implications on control solutions, the thesis has established a relation between industry specific characteristics and the way companies in the industry control their supplier relationships. The analysis is based on a theoretical framework created by Dekker (2004). Amongst other factors, the difficulty to define, quantify and measure the design variables of a fashion good, the high heterogeneity between individual products and the difficulty to predict the trend based demand, create high coordination requirements as well as appropriation concerns solved through extensive formal control.

Silver och vismut i plaster och färger : Källor till förhöjda halter i slam?

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

Beror KRAV-grisars ledanmärkningar på miljöfaktorer?

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

Stem injection of different nitrogen forms into young Norway spruce

This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).

Massbalansmodellering av fosfor i ett åländskt kustområde : en utredning om lokaliseringen av Lotsbroverkets utloppsledning

This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland?s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an ?inner water area?.The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics.

Läkemedlet Oxazepam påverkar abborryngel : Exponering under embryonalutvecklingen ger effekter på tillväxt, överlevnad och beteende

Pharmaceuticals are environmental pollutants that are a major threat to aquatic ecosystems and very little is known about their ecological consequences. In this study growth, survival and behaviour (sociability, activity and boldness) of perch fry (Perca fluviatilis) were examined in order to study the possible effects of exposure to a benzodiazepine anxiolytic drug, Oxazepam, during embryonic development. The study tested following hypotheses: (1) perch growth is affected positively by exposure during embryonic development; (2) early perch survival is affected positively by exposure during embryonic development; and (3) boldness and activity increases while sociability decreases in perch fry exposed during embryonic development. Embryos of naturally spawned perch were exposed to water with two different concentrations of Oxazepam. The embryos were exposed during different parts (24-hour periods) of the embryonic development, because embryos may be more vulnerable at certain times during embryonic development and/or because the exposure at different times can produce different effects.

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