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Klimatet har varit relativt stabilt under den nuvarande interglaciala epoken (Holocen) som inleddes för ungefär 11 700 år sedan. Genom klimatrekonstruktioner från olika geologiska arkiv såsom iskärnor, sjösediment och torvmossar har det ändå påvisats att snabba förändringar i klimatet har inträffat under denna epok. En sådan tidsperiod inträffade för omkring 2800 år sedan och den är intressant ur Geological archives have shown periods of abrupt climate change in the relatively stable Holocene epoch (last ca. 11 700 years). One of these periods was around 2800 cal BP. Several records, mainly from Europe, reveal a shift towards wetter, cooler and windier conditions. There are, however, indications for a global extent of the climate change. The climate change coincides with a distinct increas

Dactylorhiza majalis subsp. sphagnicola is an allotetraploid marsh orchid derived from parents closely similar to present-day D. incarnata and the western European form of D. maculata subsp. maculata, suggesting that it has a postglacial origin. It extends from northwestern continental Europe into areas formerly covered by the Weichselian ice sheet in mid-Scandinavia. Here, we studied the variatio

Popular Abstract in Swedish Polycykliska aromatiska kolväten (PAH) är en grupp organiska ämnen som kan vara giftiga men även starkt cancerframkallande. De bildas vid förbränning av organiskt material vid låg syretillförsel och återfinns i olika produkter som tjära och fossila bränslen. De källor som tillför störst mängd till miljön idag är bostadsuppvärmning med ved, kol och olja (i Sverige ca 2/3Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants of great environmental concern, due to their toxicity, carcinogenicity and long persistence in the environment. To determine the potential risk associated with PAHs released from contaminated soil or waste materials, knowledge is required on the leachable concentrations of PAHs and the amounts available for release. The obj

Pollen analyses and AMS C-14 measurements were performed on lacustrine sediments and peat deposits from the former crater lake Steregoiu in a mid-altitude area in the Gutaiului Mountains in NW Romania in order to provide a detailed reconstruction of the vegetational development of the area during the Late-Glacial and Holocene. The bottom sediments are siliciclastic and were deposited probably duri

Popular Abstract in Swedish Den här avhandlingen är ett bidrag till utvecklingen av en metodik som gör det möjligt att med hjälp av fossila pollen d.v.s. pollen som lagrats i mossar och sjöar, rekonstruera historiska och förhistoriska landskap så precist som möjligt vad gäller utbredning av skog, olika typer av öppen mark samt vegetationens sammansättning. Den tolknings metodik som för närvarande Fossil pollen records retrieved from peat and lake sediments have great potential for quantifying past plant cover. This thesis is a contribution to the development of a palynological interpretation tool for reconstructing past cultural landscapes in terms of plant abundance and distribution. The aims of this thesis are (1) to explore pollen-vegetation relationships in the ancient, traditional cul

Popular Abstract in Swedish Bakgrund: Patientflödet genom en akutmottagning regleras framförallt av tre typer av faktorer. Dessa rör i tur och ordning inflödet-, genomflödet- och utflödet av patienter. Faktorer som reglerar inflödet rör efterfrågan på sjukvård (t.ex. samhällsdemografi och tillgång på primärvård), medan faktorer som reglerar genomflödet till största delen rör akutmottagningens inteBackground: Emergency Department (ED) overcrowding occurs when the need for ED services outstrips available resources. Causes have been divided into input, throughput, and output factors, of which the last appear to be the most influential. Unavailability of inpatient beds (so-called “access block,” or “hospital crowding”) impairs ED output and is associated with increased waiting times in the ED

Intracerebral neural transplantation offers a new strategy to combat Parkinson’s and Huntington’s diseases. However, a host immune response against a histoincompatible neural graft in the brain may jeopardize transplant survival. We transplanted dissociated mesencephalic tissue prepared from Sprague-Dawley (SD) (syngeneic), Lewis (allogeneic) rats or mice (xenogeneic), into 6-hydroxydopamine (6-OH

Protein S deficiency is an autosomal dominant trait affecting around 10% of families thrombophilic families. The high affinity interaction of approximately 60% of protein S with C4b -binding protein (C4BP) has raised a complicated situation for the diagnosis of deficiency states. Because only free protein S functions as cofactor in the protein C anticoagulant, it is important to measure free prote

Since publication of the 1998 UNEP Assessment, there has been continued rapid expansion of the literature on UV-B radiation. Many measurements have demonstrated the inverse relationship between column ozone amount and UV radiation, and in a few cases long-term increases due to ozone decreases have been identified. The quantity, quality and availability of ground-based UV measurements relevant to a

Popular Abstract in Swedish Vid många industriella processer bildas olika typer av biprodukter, som kan vara mer eller mindre giftiga. En ovarsam hantering av de giftiga ämnena, eller en olycka, kan lätt leda till att den omgivande miljön blir förorenad. Förr, när man var mindre medveten om riskerna med de här ämnena hamnade de ofta i marken kring anläggningarna. Det har resulterat i många förorenBioremediation of soils is considered a low-cost alternative to other remediation techniques. Its ability to remove a number of different pollutants has been demonstrated, relying mainly on the activities of indigenous soil bacteria. The polycyclic aromatic hydrocarbons (PAHs) are considered major environmental pollutants in soil, some of them being toxic and others carcinogenic. Since high-molecu

Abstract in Undetermined To improve our knowledge of climate change and its impacts on ecosystem services, and to inform local people and governments that need assistance with the development of mitigation and adaptation strategies, climate impacts need to be understood urgently at the smaller scale. On one hand, the microclimate/topoclimate is known to be strongly decoupled from the general macro

Popular Abstract in Swedish Proteiner är uppbyggda av aminosyror som är hopkopplade med varandra och bildar långa kedjor som kan bestå av hundra- eller tusentals aminosyror. Det finns en mängd olika proteiner och de har många olika funktioner. I studierna som beskrivs här, har proteiner som finns på ytan av vissa bakterier studerats. De långa proteinkedjorna i dessa bakteriella ytproteiner är oftPeptostreptococcus magnus and group C/G streptococci are Gram-positive cocci that are part of the normal flora and reside in more or less the same locations in the host. Protein G of group C/G streptococci was originally described as binding IgGFc of several species and later shown to also bind human serum albumin and albumins from various animal species. From albumin-binding strains of P. magnus

The P-type plasma membrane H⁺-ATPases form a group of proteins only found in plants and fungi. The pumping of protons across the plasma membrane, energized by ATP hydrolysis, creates an electrochemical gradient that is essential for solute transport and internal pH regulation. The H⁺-ATPase genes are present as multigene families in the genomes of higher plants and all cell t

Semiconductor nanowires are studied by using transmission electron microscopy (TEM) based methods in this work. In the first section, the growth mechanism of gallium arsenide nanowires grown by chemical beam epitaxy is investigated. The nanowires are epitaxially grown from a gallium arsenide substrate by using gold seed particles as catalysts. The growth of gold particle catalysed nanowires is oft

The use of Penman-Monteith (PM) equation in thermal remote sensing based surface energy balance modeling is not prevalent due to the unavailability of any direct method to integrate thermal data into the PM equation and due to the lack of physical models expressing the surface (or stomatal) and boundary layer conductances (g(S) and g(B)) as a function of surface temperature. Here we demonstrate a

Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European effo

Populärvetenskaplig sammanfattning: Då man för ner en elektrisk ström i marken kommer vissa material i marken laddas upp p.g.a. att positiva och negativa joner samlar ihop sig på ytor och i trånga porkanaler. Detta kallas för polarisering och kan användas för att bestämma t.ex. vad för typ av geologiska material som finns under markytan eller vart föroreningar i marken tar vägen. Fenomenet som uppIt has been shown that surveys of Induced polarization (IP) often contain data of low quality, because it is highly sensitive against different noise sources. When measuring induced polarization, where the method uses multicore cables and continuous electrode sounding (CVES, Continuous Vertical Electrical Sounding), noise phenomena such as capacitive coupling effects have to be considered. It is p

Stratigrafiska analyser har utförts på en kustklint vid Ålabodarna i västra Skåne, vilken exponerar en skärning genom en liten dödisbassäng. Syftet med undersökningen var bl a att studera vegetationsutvecklingen i ett område som, i förhållande till övriga Skandinavien, tidigt blev isfritt. Fördelen med att arbeta med sediment i en öppen skärning i stället för i en borrkärna är att sedimentens latePopular abstract: A study of sediments from a small ancient lake basin in the cliffs at Ålabodarna, western Skåne, Sweden has revealed important information about the arrival and expansion of vegetation in the area. Western Skåne is a very important area for studies of this type, as the ice streams from the final episode of glaciation during the Late Weichselian retreated from this area early rela

Air sampling and biological sampling have been performed to examine the exposure to nicotine in the Nicorette patch and Nicorette gum production at Pfizer Health AB in Helsingborg, Sweden. For this purpose stationary and personal sampling equipment have been used. At the Nicorette patch production, XAD-2 tubes were used to sample nicotine vapor and at the Nicorette gum production Teflon filters we

G protein-coupled receptor 30 (GPR30) is a G protein-coupled receptor (GPCR) that is attracting considerable attention in breast cancer and cardiometabolic regulation. Following reports that GPR30 is required for some rapid estrogen responses, e.g. increased cAMP production and ERK1/2 activity, in estrogen receptor (ER)-negative cells, GPR30 was renamed G protein-coupled estrogen receptor 1 (GPER1