This thesis examines broad-scale patterns in the food web structure of lake ecosystems. The unifying framework for this analysis is the concept of trophic position, which represents the energy-weighted trophic path length leading to a consumer or population. Trophic position was estimated for over 550 populations of fish (16 species) using quantitative dietary data. A method to estimate trophic position of aquatic consumers using stable isotope ratios was developed; this involved correcting for within and among-lake variation in delta15N of primary consumers (organisms used to represent the base of the food web). We report an overall correspondence between dietary and isotopic estimates of trophic position; for each species, trophic position generally ranged the equivalent of one trophic level unit among-populations. The concept of discrete trophic levels provided only a qualitative description of energy flow pathways in aquatic food webs. Among-population variation was much greater than within-population variation in trophic position of lake trout. Long-standing hypotheses about the determinants of food chain length were examined; food chain length was most closely correlated with species richness and lake area. / The trophic position approach was used to examine two separate environmental problems relevant to lakes: the bioaccumulation of persistent contaminants in food chains and the impacts of invasive species. Trophic position was the major determinant of PCB levels in lake trout; these relationships were used to characterize biomagnification factors (BMFs) for this and a number of other contaminants. Furthermore, the introduction of smelt into lakes was linked to increased levels of PCB and Hg contamination in lake trout. Stable isotopes were used to quantify the impacts of smallmouth bass and rock bass invasions on food webs leading to lake trout. Lake trout from invaded lakes exhibited reduced consumption on littoral prey fish; a food web shift that is likely to have detrimental impacts on native lake trout populations.

When the introduction starts for the child and their parents it holds many emotions. There are many emotions involved in the first meeting between preschool and home for both the children and their parents. So my purpose with this study is to focus on two introduction models educators at my selected preschool works by. The purpose of my study is to focus on the two introduction models that are used by educators at my selected preschool. I ´m going to view this two models by examining how the educators prepare before the introduction starts and look at their point of view. In my study I m also going to look at how the parents thought before the introduction, fast started and during it. My empirical material consists of four interviews with educators and two interviews with parents. The final result showed a number of important factors that both educators and parents consider of great importance to an introduction. Educators pointed out that a good collaboration and relationship with the child’s and parents was of great importance. But one mutually point that was shared by all the educators and parents was the importance of safety during the introduction.

Studier från Amerika och Storbritannien visar att introduktionsprocesser fokuserar för mycket påprocesser, policys och värderingar och mindre på de nyanställdas upplevelser när det gäller stress,stöd till att knyta kontakter med medarbetare och otydliga arbetsbeskrivningar (Andersson, N. R,Cunningham-Snell, N. A. & Haigh, J., 1996 & Klubnik, J. P., 1987).En kvalitativ undersökning har utförts på AniCura Falu Djursjukhus. Undersökningen har genomförtsmed hjälp av intervjuer och mailkonversationer. Syftet med undersökningen är att utforska omde tidigare studierna överensstämmer med upplevelser som nyanställdas på AniCura Falu Djursjukhushar kring arbetsintroduktionen och dess påverkan angående stress, möjligheter till stöd och arbetsbeskrivningar.Nio respondenter med olika ansvarsområden deltog. Resultatet från undersökningenbekräftade att empirin överensstämde med studierna. Exempelvis fick de nyanställda självaansvara för att lära känna sina medarbetare. Undersökningen visade också att organisationen intehade någon strategi för att hantera nyanställdas stress. Det förekom heller ingen återkopplingen påintroduktionen.Undersökningsresultaten kommer i detta arbete diskuteras, analyseras och ställas mot en relevantteoretisk referensram med avseende på de aktuella ämnena för undersökningen. Slutprodukten är ettförbättringsförslag som kan ligga till grund för framtida introduktionsprocesser och vidare forskning. / Studies from America and Britain shows that the introduction processes focus too much on processes,policies and values and less on the new employees experiences when it comes to stress, supportfor establishing contacts with employees and unclear job descriptions (Klubnik 1987 & Andersson,N. R Cunningham-Snell, NA & Haigh, J., 1996).A qualitative case study has been conducted on AniCura Falu Animal Hospital. The study has beenperformed with the help of interviews and e-mail conversations. The purpose of the study is to explorewhether the earlier studies are consistent with the experiences of new employees on AniCuraFalu Animal hospital has about labor induction and its impact regarding stress, opportunities forsupport and work descriptions. Nine respondents with different responsibilities participated. Theresults of the case study confirmed that the empirical data were consistent with the studies. For example,did the new employees themselves responsible for getting to know its people and that theorganization had no strategy to cope with stress. Furthermore there was no feedback regarding theintroduction.The results will in this work be discussed and analyzed, and set against a relevant theoreticalframework around current topics of this study. The final product lands in an improvement proposalthat can form the basis for future introduction processes and future research.

Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 80-90). Also available via the World Wide Web.

Thesis (M.Sc. Biological Sciences)--University of Waikato, 2007. / Title from PDF cover (viewed April 7, 2008) Includes bibliographical references (p. 91-101)

Diss. Alnarp : Sveriges lantbruksuniversitet, 2005.

Thesis (Ph.D.)--University of Adelaide, School of Agriculture and Wine, Discipline of Plant and Pest Science, 2004? / "August 2003." Includes bibliographical references (leaves 294-333).

Thesis (Ph.D.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 124-146.

Thesis (M. Sc.)--University of Stellenbosch, 2008. / Includes bibliographical references. Also available via the Internet.

Thesis (Ph.D.)--University of Washington, 1994. / Vita. Includes bibliographical references.