No description available.

Sammanfattning Syftet med rapporten var att ta reda på hur förskolan anpassar lärandesituationer för barn i behov av Alternativ och Kompletterande Kommunikation (AKK) samt hur AKK används vid naturkunskapsundervisning. Metoderna för rapporten är observation och intervjuer. Jag sökte information via Internet, litteratur och rapporter. Huvudresultatet av rapporten visar att förskolan arbetar med tecken som stöd, objekt, gester, ord, bilder, sinnen och Karlstadmodellen. Undervisning sker i naturliga situationer och enskilt barn – pedagog. Pedagogers utbildning, fortbildning och handledning är mycket viktig för barnets språkutveckling. Slutsatser är att pedagoger skall vara pålästa och kunniga i barnets AKK för att tolka barnet och förmedla situationer som uppstår under en dag. Språktester hjälper barn att hitta lämplig AKK. Pedagogen skall vara och lära tillsammans med barnen i aktuella situationer samt låta barnen praktiskt prova och undersöka med sina sinnen, barnen bör även ha distans till oss vuxna ibland, en vrå att dra sig undan i. Nyckelord: AKK, förskolan, naturkunskap, undervisning

Syftet med detta arbete var att undersöka huruvida trevärt aluminium, Al3+, inverkar på nitratupptaget hos veteplantor (Triticum aestivum L.). Vidare avsågs att undersöka om koncentrationen av jonen ifråga är av betydelse. Hypotesen som testades var att trevärda aluminiumjoner verkar hämmande på nitratupptaget och att hämningsgraden stiger med ökad koncentration av aluminium. I försöket användes veteplantor som togs i bruk på sjunde dagen efter det att de planterats i vermikulit. Provlösningarna utgjordes av fyra stamlösningar som endast skilde sig åt med avseende på aluminiumjonskoncentrationen. I en av lösningarna fanns inget tillsatt aluminium och i de andra förekom aluminium i 3, 12 respektive 24 μM. Halten nitrat var densamma i alla lösningarna och uppgick till 645 M. Plantorna fick stå i provlösningarna med genomluftning under 16 timmar. Provlösningarna analyserades spektrofotometriskt. För att tömma apoplasten fick plantorna stå i destillerat vatten under 20 minuter. Sedan torkades plantorna i 5 timmar varefter de vägdes. Resultaten visade på signifikant skillnad mellan referens och 3 μM Al relativt 12 respektive 24 μM Al. Nitratupptaget var signifikant lägst i 24 μM Al och näst lägst i 12 μM Al. Ingen signifikant skillnad kunde påvisas mellan referens och 3 μM Al. Försöket indikerar att Al3+ har en hämmande verkan på nitratupptaget hos det veteslag som här har använts och att denna hämning tilltar med stigande koncentration av Al3+ i lösningen över de koncentrationer som brukats i denna studie. / The aim of the study was to investigate whether Al3+ affects the uptake of nitrate in wheat seedlings (Triticum aestivum L.). Furthermore the aim was to investigate if the concentration of the ion had any importance. The hypothesis at trial was that Al3+ has an inhibiting effect on the nitrate uptake and that the effect increases with elevated concentrations of aluminium. In the trial wheat seedlings were used on the seventh day after being planted in vermiculite. The test solutions were four stem solutions which only differed in the aluminium concentration. In one of the solutions there was no aluminium added. Further on aluminium were used at 3, 12, and 24 micro molars. The nitrate level was the same in all solutions and the amount was 645 μM. The plants were kept in the test solutions for 16 hours with aeration. The test solutions were analyzed spectrophotometricaly. The apoplast was empted by placing the plants in distilled water for 20 minutes. Afterwards the plants were dried for 5 hours and then weighed. The result showed significant difference between the reference and 3 μM Al in respect to 12 respectively 24 μM Al. The nitrate uptake was significantly lowest in 24 μM Al and second lowest in 12 μM Al. No significant difference could be shown between reference and 3 μM Al. The study indicates that Al3+ has an inhibiting effect on the nitrate uptake of the wheat type which been used here and that the inhibition increases with elevated concentrations of Al3+ in the solutions over the range of concentrations used in this study.

Abstract Surface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden. In this specific pond, plants such as reed, reed mace and broad-leafed pondweeds are the most common plants. Several studies show that plants have the ability to accumulate and store heavy metals. Reed, reed mace and broad-leafed pondweeds in the surface-water pond at Bergviks shopping centre all contains arsenic, lead, cadmium, chrome, cobalt, copper, nickel and zinc. The results in this study show a significant difference between these three plants in their heavy metals concentration. Broad-leafed pondweed had significantly higher concentrations of chrome, cobalt, copper, nickel, vanadium and zinc than reed and reed mace. Cadmium, copper and zinc also occurred in higher concentrations in broad-leafed pondweeds than in the sediment of the pond. Broad-leafed pondweed has the ability to accumulate heavy metals directly from the water while reed and reed mace only accumulate heavy metals with their roots. This could help explain the higher concentration in broad-leafed pondweed, in comparison to reed and reed mace. Due to the high metal concentration in the broad-leafed pondweed, it is appropriate to put this plant in surface-water ponds, in order to elute the water from heavy metals. Regular harvesting of the broad-leafed pondweed from the surface-water pond, together with regular cleaning of the sediment may reduce the occurrence of heavy metals in the recipient of Kattfjorden.

No description available.

In this thesis, I used the filamentous ascomycete genus Neurospora as a model to test theoretical predictions on the evolutionary consequences of different reproductive strategies and reproductive gene evolution. The genus Neurospora contains taxa representing a diversity of reproductive strategies, and here I constructed a phylogeny by which I was able to show that several independent transitions in reproductive mode have occurred in the evolutionary history of the genus. This feature makes Neurospora a suitable model for the evolution of reproductive modes. Molecular evolutionary analysis of housekeeping genes revealed an accelerated protein evolution in the highly inbreeding homothallic taxa, in accordance with theory predictions of lower efficiency of selection in asexual and highly inbreeding taxa. Furthermore, self-sterile (heterothallic) taxa capable of asexual propagation was found to be associated with a three-fold higher neutral substitution rate, indicative of a higher mutation accumulation due to elevated number of cell divisions per unit time in these taxa. Further, I have shown a general pattern of rapid evolution of genes involved in reproduction in Neurospora, thus extending the pattern of general high divergence of reproductive genes previously well known in animals, to fungi. Two rapidly evolving reproductive genes: the pheromone receptor genes pre-1 and pre-2 involved in mate recognition were studied in detail. For the gene pre-1 the rapid divergence was found to be driven by positive selection in both heterothallic and homothallic taxa. The rapid divergence of the pheromone receptor gene pre-2 cannot be explained by positive selection and for this gene a subtle differences in evolutionary constraints between heterothallic and homothallic taxa were found. The general similarity in evolutionary constraints of pre-genes in taxa of both mating-systems indicates that these genes serve other functions beside mate recognition.

Direct effects of the insecticide deltamethrin on zooplankton and benthic invertebrates werestudied during an attempt to eradicate signal crayfish. In accordance with earlier studies theresults of this investigation showed that deltamethrin is highly toxic for arthropods, whileRotifera, Oligochaeta and Mollusca have a higher tolerance. This study concludes thatRotifera in treated ponds coped with the actual concentration of deltamethrin used during theeradication attempt but that they probably got a different abundance and changed compositiondue to a new situation in competition and predation. Crustacean zooplankton totallydisappeared, but approximately a month after the treatment they began to recolonise. All thetaxonomical groups of arthropods drastically decreased in abundance, with total eliminationof the most sensitive groups. The concentration of deltamethrin was not higher than that somespecies of Hydracarina and Chironomidae survived.

The effects of prey size on prey choice in different cohorts of juvenile turbot (Psetta maxima)were studied in three nursery areas at Gotland. Prey length measurements showed that gobies(Gobiidae) increased in average length during the season, while mysids (Mysidae) did not.Experiments on predation capacity of different size classes of turbot on different size classesof prey showed that juvenile turbot easily can eat gobies that are up to two thirds of their ownbody length, while the body size of turbot does not have any effect on the predation capacityon mysids. Stomach content of 217 turbots, less or equal 35 mm, was analysed to see if therewas any change in diet during the season, but there was no significant change in diet. Theoverall conclusion was that early settlers most likely have an advantage due to greater accessof alternative prey.

No description available.

<p>Syftet med examensarbetet är att göra en läromedelsanalys för att undersöka om läroböcker för Biologi A, BI1201 för gymnasieskolan, uppfyller kursmålen. De böcker som används är Biologi Kurs A Anders Henriksson (2000), Biologi A med Naturkunskap A Janne Karlsson m.fl (2000), Liv i utveckling Lars Ljunggren m.fl (1999) och Biologi A Peinerud m.fl (2000). För Biologi Kurs A användes även lärarhandledning.</p><p>Resultatet visar att det är endast en av läroböckerna, Peinerud m.fl, som uppfyller alla kursmål som finns uppsatta. Även Henrikssons bok uppfyller kursmålen när den kompletteras av lärarhandledningen. En av böckerna, Ljunggren m.fl uppnår endast två av åtta kursmål. Trots att författarna ska utgå ifrån de kursmål som är uppsatta för kursen när de skriver läroboken, så är det ändå inte samtliga läroböcker som uppfyller kursmålen. Används läroboken som primär kunskapskälla finns det därför risk att alla kursmål inte uppfylls. Läroböckerna måste därför kompletteras med andra läromedel, till exempel tv eller internet.</p>