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Setting the Holocene clock using varved lake sediments in Sweden

Popular Abstract in Swedish Under kvartärtiden (den geologiska period som omfattar de senaste ca 2,6 miljoner åren) har klimatet på Jorden varierat dramatiskt. Långa perioder (ca 100 000 år) av istid med stora inlandsisar som täckte Skandinavien, Ryssland, Sibirien, Grönland och Nordamerika har periodiskt avbrutits av kortare perioder (ca 10 000 år) av varmare klimat, så kallade interglacialer. HoThe aim of this thesis was to study annually laminated (varved) Holocene lake sediment in Sweden, their formation and their potential as chronological and palaeoecological archives. Five lakes with continuous Holocene varved lake sediment sequences in northern (Västerbotten) and west central Sweden (Värmland) were investigated. Three of these sequences were discovered during this study, which iden

Evolution of parasitism in nematode-trapping fungi

We are studying the evolution of parasitism in a group of soil-living ascomycetes that can grow as saprophytes as well as parasites by forming special morphological structures called traps. Analyses of 18S ribosomal DNA sequences have shown that these fungi form a monophyletic and isolated clade among the ascomycetes. The phylogenetic patterns within this clade are concordant with the morphology o

Modelling of coastal evolution on yearly to decadal time scales

There is still no universal model for analysing and predicting coastal evolution and its governing processes on yearly to decadal time scales. Instead, depending on the nature of the problem and project objectives, there is a wide range of models available, each focusing on the problem complex from a specific standpoint. The present paper gives an overview of available numerical model types. A dif

On the typification and application of Hieracium diaphanum Fr., with remarks on the diagnostic characters of allied species from southern Sweden

A lectotype for Hieracium diaphanum Fr. (1819) is designated and it is compared with similar species from southern Sweden, i.e. H. pseudodiaphanum (Dahlst.) Johanss., H. jonsbergense T. Tyler, H. hemidiaphanum (Dahlst.) Brenner, H. dalicum Johanss. and H. subglaucovirens Zahn ex Johanss. & Sam. It is concluded that the name H. diaphanum (s. stricto) does belong to a very rare species hitherto

Svenskhetens historia

Recension av Patrik Hall, Den svenskaste historien. Nationalism i Sverige under sex sekel.

Finite Element Procedures in Modelling the Dynamic Properties of Rubber

Popular Abstract in Swedish Gummi är inte enbart olinjärt elastiskt, det är också beroende av töjningshastighet och töjningsamplitud. Kombinationen av de olinjära elastiska egenskaperna och amplitudberoendet behandlas av de modeller som föreslås i avhandlingen. Modellerna är utformade så att de snabbt ska kunna implementeras i industrin.Rubber is not only a non-linear elastic material, it is also dependent on strain rate, temperature and strain amplitude. The non-linear elastic property and the strain amplitude dependence give a non-linear dynamic behavior that is covered by the models suggested in this thesis. The focus is on a finite element procedure for modelling these dynamic properties of rubber in a way that is easy to ado

The dysmetabolic syndrome

The first unifying definition for the metabolic syndrome was proposed by WHO in 1998. In accordance to this, patients with type 2 diabetes mellitus or impaired glucose tolerance have the syndrome if they fulfil two of the criteria: hypertension, dyslipidaemia, obesity/abdominal obesity and microalbuminuria. Persons with normal glucose tolerance (NGT) should also be insulin resistant. About 40% of

Growth interaction between different tumor populations in human endometrial adenocarcinoma growing in nude mice

In these studies of tumor cell growth interaction we have used two tumors differing from each other in sensitivity to estradiol, transplanted to opposite sites of the same nude mice. In the first experiment we found that the growth of an estradiol-sensitive tumor may be delayed by the presence of an estradiol-resistant tumor in the same animal. Although the growth pattern was changed, proliferativ

Calculation of the minimum amount of blow-through steam for condensate drainage in paper drying cylinders

A model is presented for calculating the minimum amount of blow-through steam for condensate drainage in paper drying cylinders. Two criteria for cylinder flooding are given. First, the condensate must be lifted from the inner cylinder wall by the decrease in pressure in the siphon inlet. Secondly, the drag force on the drops in the siphon tube must be higher than the centrifugal force acting in t

A general model for calculating pressure drop in siphons and siphon riser tubes. Part 1: Principles and theoretical model

A general model for pressure drop calculations in siphons and riser tubes has been developed. The model takes into account different physical flow phenomena such as inlet pressure drop and pressure drop in the tube. For each phenomenon, we applied theory and established correlations to calculate the separate accelerational, frictional, gravitational, and centrifugal pressure drops. Model results a

On the experimental validation of a non-linear shaft damping model

This paper presents an experimental validation of a proposed non-linear damping model for shaft torsional vibration studies, compared to the linear viscous damping model. Nine different shaft configurations were used. The deflection of each shaft exhibiting free vibration was measured for a period of one minute and the signal component at the natural frequency of torsion was found. The experiments

Intracellular and interstitial expression of Helicobacter pylori virulence genes in gastric precancerous intestinal metaplasia and adenocarcinoma

Gastric intestinal metaplasia (IM) and gastric cancer are associated with Helicobacter pylori, but the bacterium often is undetectable in these lesions. To unravel this apparent paradox, IM, H. pylori presence, and the expression of H. pylori virulence genes were quantified concurrently using histologic testing, in situ hybridization, and immunohistochemistry. H. pylori was detected inside metapla

LD-isoenzym i uterusaspirat potentiell markör för endometriecancer. Utredning av postmenopausal blödning kan bli enklare och billigare

n diagnosing endometrial carcinoma in women with postmenopausal bleeding analysis of lactate dehydrogenase, LD, isoenzymes in uterine aspirates appeared to have 100 per cent sensitivity and negative predictive value combined with high specificity and positive predictive value. Determination of the LD-profile is suggested as a marker for endometrial carcinoma in women with postmenopausal bleeding.

Changing aneurysmal morphology after endovascular grafting: relation to leakage or persistent perfusion

PURPOSE: To relate changing abdominal aortic aneurysm (AAA) morphology after endovascular grafting to the presence of leakage, collateral perfusion, and other factors. METHODS: Thirty-five patients who underwent successful AAA endovascular grafting were evaluated. Self-expanding Z-stents and Dacron grafts were applied in bifurcated and aortomonoiliac systems. Postoperative diameter changes were ca

Effects of pre-treatment technologies on quantity and quality of source-sorted municipal organic waste for biogas recovery

Source-sorted municipal organic waste collected from different dwelling types in five Danish cities and pre-treated at three different plants was sampled and characterized several times during one year to investigate the origin of any differences in composition of the pre-treated waste introduced by city, pre-treatment technology, dwelling type or annual season. The investigated pre-treatment tech