Contaminated soils and sediments have been identified as significant secondary sources of organic contaminants.  Leaching tests may be useful tools to estimate the mobility of contaminants via the water phase and thereby the risk for groundwater and surface water contamination. The influence of soil composition (peat and clay content) on the leachability was investigated in batch leaching experiments for chemically diverse hydrophobic organic compounds (HOCs: PCP, PAHs, HCB, HCHs, PCBs, and TCDD/Fs). The above mentioned compounds were analyzed by both GC-LRMS (gas chromatography coupled with low resolution mass spectrometry (GC-HRMS) and GC-HRMS (gas chromatography coupled with high resolution mass spectrometry). Also the the leachability of eleven selected PCBs from naturally aged soil (Västervik, Sweden) was investigated in relation to the composition and concentration of dissolved organic matter at different pH (2 to 9), using a pH static test with initial acid/base addition. The the composition and of dissolved organic matter (DOM) at different pH values was explored by FTIR spectroscopy. The results were evaluated by orthogonal projections to latent structures (OPLS). Generally, for all model compounds studies, the Kd-values showed a variability of 2-3 orders of magnitude depending on the matrix composition. The Kd-values of moderately hydrophobic compounds, (e.g. HCHs, PCP and Phe), were correlated mainly with the organic matter content of soil. For more hydrophobic compounds (e.g.BaA, HCB and PCB 47), the leachability decreased as the proportions of  OM and clay contents increased. The Kd-values of 1,3,6,8-TCDD and 1,3,6,8-TCDF were  positively correlated with peat content but negatively correlated with clay content, while for PCB 153 and PCB 155 the correlations were reversed. The log Kd-values of all target PCBs decreased with increased pH values and the log Kd-values were highly correlated with the concentration of total organic carbon (TOC) in the leachates. The FTIR analysis of DOM showed that the least chlorinated and hydrophobic PCB congeners (i.e. PCB 28) might be associated with the hydrophilic fraction (i.e. carboxylic groups) of DOM. Our study demonstrated how complex interaction between the organic matter, clay components, pH and DOC influences the leachability of HOCs in a compound-specific manner.

No description available.

Calculations on stress, strain and deformation are typically made using finite element methods (FEM). An alternative to this is a rigid bodydynamics approach also called lumped element method (LEM). LEM implements deformation by replacing single rigid bodies with multiple subbodies, which are in turn connected with joints (also called constraints) that allow movement between the sub-bodies. If instead of FEM, a lumped element method is used to simulate deformable objects, sufficient accuracy can be obtained at a much lower cost, complexity-wise. A lumped element method-approach could for example achieve real-time simulationspeed. The purpose of this thesis is to expand upon previous work into LEM, analyzing how the rigid bodies and constraints should be configured to produce accurate results for a wider range of objects. Specifically, beams of varying cross section and curved beam axis, as well as other test cases. The simulated values are compared with the analytic predictions given by Euler-Bernoulli beam theory. These simulations are implemented using the AGX Dynamics physics engine from Algoryx Simulation AB. One intended application area of LEM is crane arms. This motivates the focus on analyzing how LEM behaves when simulating beams, as they represent the most basic version of crane arms. Simulation and testing of full crane objects was unfortunately not accomplished, partly due to a lack of convenient testing data. Further work is needed to confirm that LEM behaves well for these expanded cases as well. In addition to the analysis section above, the purpose is also to implement a pipeline for automatic conversion of a CAD-model to a lumped element version in AGX. Specifically, a CAD-model given in the 3D-modeling software SpaceClaim.

Muskelstyrka och muskelmassa avtar med stigande ålder och är associerat med mortalitet, svaghet, osteoporos, fall och frakturer. Hos yngre individer har magnesiumtillskott signifikant ökat muskelstyrka. Det rekommenderade dagliga intaget (RDI) av magnesium enligt Nordiska näringsrekommendationer (NNR) är lägre än rekommendationen av U.S Food and Nutrition Board (FNB). Syftet med detta litteraturarbete var att studera publicerad litteratur inom ämnet magnesium och muskler med avsikt att undersöka ifall ett ökat magnesiumintag hos individer över medelåldern påverkar muskelstyrka och relativ muskelmassa samt undersöka vilka livsmedel som ur ett ekonomiskt perspektiv kan konsumeras för att bidra till att NNR´s RDI uppnås. Litteratursökning identifierade sex artiklar som var relevanta för frågeställningen ”Kan en högre dos magnesium öka muskelstyrka?”. Samma artiklar användes för ytterligare en frågeställning; ”Kan en högre dos magnesium förbättra relativ muskelmassa?”. Litteratursökning för den andra frågeställningen identifierade inte fler artiklar som var relevanta för frågeställningen. För den tredje frågeställningen ”Vilka livsmedel kan med fördel ur ett ekonomiskt perspektiv bidra till ett högre intag av magnesium?” användes information från Livsmedelsverkets livsmedelsdatabas och medelvärdet av tre livsmedelsbutikers jämförelsepriser. Sammanställningen av den forskning som finns visade att en kost som uppnår NNR´s dagsrekommendation främjar muskelstyrka men det gjorde inte ett högre intag av magnesium via kosttillskott. Ett ökat intag av både dietärt och supplementärt magnesium observerades främja relativ muskelmassa men det verkar som att dietärt magnesium har högre biotillgänglighet än magnesium i kosttillskott. De mest ekonomiska livsmedlen som kan konsumeras för att bidra till en högre dos magnesium i kosten var fullkornsprodukter som frukostflingor, pasta och hårt bröd. / Muscle strength and muscle mass declines with increasing age. This is associated with mortality, frailty, osteoporosis, falls and fractures. Magnesium supplementation has been shown to increase muscle strength significantly in young subjects. The recommended daily amount of magnesium according to Nordic nutrition recommendations (NNR) is lower than that of U.S. Food and Nutrition Board (FNB). The aim of this thesis work was to study published literature on the subject magnesium and muscle in order to investigate if an increased magnesium intake in subjects middle aged or older affects muscle strength and relative muscle mass and to evaluate which common foods contributes the most to achieve the RDI of NNR from an economic point of view. Searches identified six articles relevant to the issue “Could an increased dose of magnesium improve muscle strength?”. The same articles were used to answer a second issue; “Could an increased dose of magnesium improve relative muscle mass?”. Searches for the second issue did not yield more articles relevant to the issue. For the third issue; “Which foods has, from an economic point of view, an advantage in contributing to a higher magnesium intake?” information from the Swedish food agency´s food database was used and the mean cost from three different food chains comparison prizes. A compilation of data from the published scientific studies showed that a diet which fulfills the recommended daily amount of magnesium according to NNR promotes muscle strength in subjects middle aged or older; however, an increased amount of magnesium taken as a supplement did not show any significant increase in muscle strength. An increased intake of both dietary and supplementary magnesium promoted relative muscle mass, but the bioavailability of dietary magnesium seems to be higher than the bioavailability of supplements. The most economic groceries which contributes to a higher dose of magnesium in the diet was full grain products such as breakfast cereals, pasta and hard bread.

The tree amplitudes of string theory low-energy effective actions admit a diagrammatic expansion in terms of higher-than-cubic contact terms. These tree amplitudes can be used to build loop amplitudes using unitary cuts or the forward limit. In this thesis we study the possibility of constructing four-point cubic representations for the resulting one-loop contact terms that obey the Bern-Carrasco-Johansson (BCJ) color-kinematics relation. From the string theory effective action we study the contact terms carrying ζ2, ζ3, ζ4, and ζ5. For the even ζ2 and ζ4 cases we find that the cubic representations are incompatible with the BCJ relations, as expected from their disappearance in the closed-string effective action. We find a unique, local set of numerators at ζ3 that obey the BCJ relations. For ζ5 we find two choices of representations: one obeys BCJ but requires non-trivial contributions for the tadpole; the other contains no tadpoles but breaks one of the BCJ relations.

I den här uppsatsen undersöker jag hur biologilärare på högstadiet försöker få elever nyfikna. Nyfikenhet är ett viktigt ämne att studera eftersom nyfikenhet är det som leder personer till att utforska världen och är det som har lett till den vetenskap vi har idag. Den här studien kan användas av lärare för att lära sig om hur andra lärare försöker inspirera till nyfikenhet. Den öppnar även upp för fler tankar kring nyfikenhet som skulle kunna utforskas mer. För att få reda på hur lärare försöker få elever nyfikna intervjuade jag fem lärare och använde mig av intervjuerna för att titta på mönster som kunde hittas. Några av de saker som kom fram var att flera av lärarna tyckte att det var bra att använda sig av praktiska inslag som laborationer för att få elever nyfikna, att elever främst verkar uttrycka sin nyfikenhet genom att ställa frågor alternativt att de uttrycker det på fler sätt men lärare märker inte det. Framförallt kom det fram att trygghet och bra relationer är viktiga för att eleverna ska våga visa sin nyfikenhet och att lärare ska själva visa sitt intresse för att få elever mer nyfikna.

No description available.

A greater consumption of pharmaceutical drugs entails an increased concentration of active benzodiazepines in aquatic ecosystems. Consequently, aquatic organisms are experiencing altered behavior that may affect dominance hierarchies since social status (among other variables) is associated with behavioral traits. The aim of this study was to determine whether dominance hierarchies of brown trout (Salmo trutta) were affected by exposure to a benzodiazepine (oxazepam). Hypothetically, aggression (in dominants) and anxiety (in subordinates) will reduce following exposure. The fish should consequently display a significant disparity between treatment groups regarding the frequency of dominance change (i.e., who is dominant versus subordinate). This research included behavioral coding of 150 juvenile brown trout (Salmo trutta) divided into 50 size-matched social groups of 3 individuals. Each group was exposed to one of three oxazepam concentrations (30 µg/L, 1.5 µg/L and 0 µg/L). The results indicate no relationship between an altered aggression and oxazepam exposure. In addition, the level of aggression reduced over time (regardless of social status and concentration) and the initial subordinates remained significantly less aggressive than the initial dominants. The frequency of dominance change did not differ significantly between different treatment groups. Body size did not affect social status. The results in low treatment groups may be due to a low bioconcentration since previous research exhibited similar results. However, the lack of results in high treatment groups could be due to something else. In conclusion, the dominance hierarchy was not disrupted by oxazepam exposure because aggression was unaffected.

<p>QC 20150603</p>

Denna studie behandlar energibegreppet i geografiämnet. Energibegreppet är komplext, inte minst för att det behandlas i olika kontexter med olika betydelser. Som lärare i naturvetenskapsämnena vill man förstå elevernas lärande om naturvetenskapliga begrepp, även om lärandet ligger utanför de egna ämnena. Syftet med studien är därför att kvalitativt undersöka hur energibegreppet behandlas i geografiämnet för att få en djupare förståelse för hur naturvetenskapsundervisningen och geografiundervisningen kan komplettera varandra. Sex samhällskunskapslärare i årkurserna 4–6 intervjuades om deras användning av energibegreppet. Deras uttalanden tematiserades och jämfördes med de fyra nyckelidéer om energibegreppet som Duit lyfter fram som centrala ur ett naturvetenskapligt perspektiv. Tre nyckelidéer kunde identifieras i lärarnas beskrivningar av hur de behandlar energibegreppet i geografiämnet. Tre teman kunde också urskiljas i datan. Studien pekar på att energibegreppet behandlas i geografiämnet med viss förankring till energiomvandling och energiöverföring. Vilket gör det möjligt att arbeta med ämnesövergripande undervisning gällande energibegreppet. / This study deals with the energy concept in the school subject of geography. The energy concept is complex, not least because it is treated in different contexts with different meanings. As a science teacher, you want to understand the students' learning about science concepts, also such learning that is outside their subject. The aim of the qualitative study is therefore to investigate how the energy concept is treated in the subject of geography in order to gain a deeper understanding of how science teaching and geography teaching can complement each other. Six social science teachers in middle school were interviewed about their use of the energy concept. Their statements were thematized and compared with the four key ideas about the energy concept that Duit highlights as central from a scientific perspective. Three key ideas could be identified in the teachers' descriptions of how they treat the energy concept in the subject of geography. Three themes could also be distinguished in the data. The study indicates that the energy concept is treated in the subject of geography with some base in energy transformation and energy transfer. That makes it possible to work interdisciplinary regarding the energy concept.