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Popular Abstract in Swedish Svängningar i antalet individer hos en organismgrupp har under lång tid intresserat forskningen. Men sådana fluktuationer i populationer har inte bara ett vetenskapligt intresse. En ökad förståelse för fenomen som dessa kan hjälpa oss att fatta bättre beslut rörande mänskliga aktiviteter såsom fiske, jakt, skogsbruk och jordbruk och förhoppningsvis leda oss mot ett mer We are interested in the effect of harvesting on population fluctuations and for that purpose we develop and analyze an age-structured model where recruitment is a stochastic process and the adult segment of the population is harvested. When a constant annual harvest is taken the coefficient of variation of the adult population increases for most parameter values due to the age truncation effect,

Popular Abstract in Swedish Den eosinofila granulocyten är en typ av vit blodkropp som ingår i kroppens immunförsvar. Vid allergirelaterade sjukdomar ses en ökad mängd av eosinofiler i blodbanan samt lokalt i den allergiskt inflammerade vävnaden. I vävnaden släpper eosinofilerna ut sina granulaproteiner som har celldödande, immunförsvarsreglerande och tillväxtfrämjande egenskaper. Hos patienter meIn allergic disorders, the eosinophilic granulocytes migrate to affected tissues and release granule proteins with cytotoxic, immunoregulatory, and remodeling-promoting properties. Given that degranulation is reflected by a loss in eosinophil granule density of living cells, or by cell membrane rupture and release of intact granules, these morphological changes may represent a biomarker of the all

Popular Abstract in Swedish Proteiner är biologiska molekyler som kan utvinnas ur olika bakterier, svampar, djur och människor. I sin naturliga miljö bidrar de bl. a. till att katalysera (snabba på) olika kemiska reaktioner (enzymer), att sköta transporten av olika molekyler, bidra till immunförsvaret och tillväxtkontroll (hormoner). Upptäckten att proteiners olika funktion kan uttnyttjas i många The effect of different additives on protein stability was studied, and the basis for stabilization was investigated at molecular level. The addition of sorbitol enhanced thermal stability of hen egg white lysozyme in aqueous solution. NMR spectroscopy revealed changes in the relaxation properties of Ala and Thr methyl groups in lysozyme, indicating compression of the enzyme as a consequence of pr

Popular Abstract in Swedish Stroke och hjärtstopp innebär ett minskat eller obefintligt blodflöde (ischemi) till hjärnans celler. Dessa celler är speciellt känliga för ischemi och om blodtflödet är lågt under en längre period leder det till obotliga hjärnskador. Varje år drabbas ungefär 50 000 personer i Sverige av hjärnischemi, vilket gör tillståndet till ett av de vanligaste orsakerna till handiCerebral ischemia is a major cause of mortality and morbidity in the western world. Even though much effort has been put into research and development of effective drugs against ischemic damage there is to date no effective pharmacological brain protective treatment. In order to study particular molecular mechanisms, isolated cellular events and the contribution of individual factors in ischemic d

This thesis deals with three topics concerning the synthesis of non-natural also known as unnatural amino acid derivatives. In the first, solvent-free reaction conditions for the Heck reaction were developed that were superior to previous conditions because the reaction time could be reduced and the work-up procedure simplified. Appropriately substituted, unnatural amino acid derivatives, synthesi

Popular Abstract in English Since the onset of the 20th century, human society has been using non-renewable resources, mainly oil, for the production of fuels and chemicals that are now an integral part of our everyday life. In the last few decades however, concerns regarding environmental effects, geopolitical issues and the eventual depletion of oil have led to us re-evaluating our dependency onConcerns regarding environmental issues such as greenhouse gas emissions and climate change have led to a shift within the research community and chemical and energy industry sectors for finding sustainable routes for producing fuels and chemicals from renewable resources, thereby minimizing our dependence on petroleum. The C3-chemical 3-hydroxypropionic acid has been identifed as a top candidate