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The Changing Nature of the Protein Folding Transition State: Implications for the Shape of the Free-energy Profile for Folding

According to landscape theory proteins do not fold by localised pathways, but find their native conformation by a progressive organisation of an ensemble of partly folded structures down a folding funnel. Here, we use kinetics and protein engineering to investigate the shape of the free-energy profile for two-state folding, which is the macroscopic view of the funnel process for small and rapidly

Dynamic FDG-PET is useful for detection of cholangiocarcinoma in patients with PSC listed for liver transplantation

Five to 15% of patients with primary sclerosing cholangitis (PSC) develop cholangiocarcinoma (CC) with a median survival of 5 to 7 months, an outcome not significantly improved by liver transplantation. However, if CC is found incidentally during the procedure or in the explanted liver, 5-year survival rates of 35% are reported. A noninvasive method to detect CC small enough to allow for intended

Laser-induced fluorescence used in localizing atherosclerotic lesions

We have investigated laser-induced fluorescence frompost mortem human arteries in order to find spectroscopic properties allowing discrimination between normal and atherosclerotic vessel wall. A pulsed nitrogen laser emitting light at a wavelength of 337.1 nm was used as an excitation source. The fluorescence spectrum from 370 to 700 nm was captured and analysed by an optical multichannel analyser

Vertical dislocation of the C1 and C2 vertebrae in rheumatoid arthritis

In a retrospective analysis of 450 patients with rheumatoid arthritis the cervical films were reviewed to detect vertical dislocation of the C1 and C2 vertebrae. A frequency of 10 per cent was found among all patients and of 24 per cent among those with cervical arthritis. The authors' method of measuring vertical dislocation at conventional radiography turned out to be superior to the method of M

On the Treatment of Flow in Traffic Safety Analysis, - a non-parametric approach applied on vulnerable road users

Popular Abstract in Swedish ”Behandlingen av trafikflöde vid trafiksäkerhetsanalyser - ett icke-parametriskt angreppssätt applicerat på oskyddade trafikanter” Det finns en lång tradition av att beakta trafikflöden inom trafiksäkerhetsområdet. Inverkan av flödet har dock ofta betraktats som så självklart att det använts utan eftertanke. I denna avhandling kan jag däremot visa att relationen mellaThe treatment of flow in the area of traffic safety has a long tradition. The influence flow has on the number of accidents is, however, often considered so obvious that it tends to be trivial. In this thesis I can show that the relation between flow and accidents holds interesting information. In order to compare countermeasures, or conduct other types of traffic safety comparisons where the flo

Experimental excursions on adaptive landscapes: Density-dependent selection on egg size

Theories of density-dependent natural selection suggest that intraspecific competition will favor juveniles of high competitive ability. Empirical evidence has been provided from laboratory selection experiments, but field studies are lacking due to the logistical difficulties of experimentally manipulating population densities in natural settings. Here, we present data from a decade long experime

Space-time-frequency (STF) coding for MIMO-OFDM systems

We consider the capacity of multiple-input-multiple-output (MIMO) systems that use OFDM as the modulation format. We point out a basic equivalence between antennas and OFDM-tones. This similarity immediately allows us to essentially reuse all space-time codes designed for flat-fading channels in MIMO-OFDM systems operating in frequency-selective channels. An optimum code would thus code across all

Sextus Empiricus against Aelius Aristides. The Conflict between Philosophy and Rhetoric in the Second Century A.D.

The subject of this study is the re-intensified dispute between rhetoric and philosophy in the times of the Second Sophistic. The focus of our investigation has been on two authors of this period who have left behind treatises the explicit purpose of which is to attack or defend rhetoric: Sextus Empiricus who is sharply criticising rhetoric and Aelius Aristides who is defending it. Our purpose has

Effect of Footwear Insulation on Thermal Responses in the Cold

The influence of footwear insulation on foot skin temperature in the cold at low activity was investigated. Simultaneously, the thermal and pain sensations, and the influence of steel toe cap were studied. Eight subjects were exposed for 85 minutes to three environmental temperatures (+3; -12 and -25 °C) wearing 5 different boots. Insulation of footwear was determined with a thermal foot model. Th

Boosting for High Load HCCI

Homogeneous Charge Compression Ignition (HCCI) holds great promises for good fuel economy and low emissions of NOdx and soot. The concept of HCCI is premixed combustion of a highly diluted mixture. The dilution limits the combustion temperature and thus prevents extensive NOdx production. Load is controlled by altering the quality of the charge, rather than the quantity. No throttling together wit

Decreasing rate of fatty involution at screening mammography

RATIONALE AND OBJECTIVES: This study was performed to document the perceived decrease in fatty involution at screening mammography during the past decade and evaluate the influence of hormone replacement therapy (HRT). MATERIALS AND METHODS: In December 1996, the mammograms of 261 consecutive screening patients with a comparison study obtained 5 years earlier were evaluated, and their breasts were

Multi-component carbon isotope evidence of early Holocene environmental change and carbon-flow pathways from a hard-water lake in northern Sweden

A 9000-year carbonate-rich sediment sequence from a small hard-water lake in northernmost Sweden was studied by means of multi-component stable carbon isotope analysis. Radiocarbon dating of different sediment fractions provides chronologic control and reveals a rather constant hard-water effect through time, suggesting lake has remained hydrologically open throughout the Holocene. Successive depl

Mechanism of metabolite transfer in coupled two-enzyme reactions involving aldolase

Transient-state kinetic experiments and analyses have been performed to examine the validity of hitherto unchallenged evidence proposed to be indicative of a channelled transfer of triose phosphates from aldolase to glyceraldehyde-3-phosphate dehydrogenase and glycerol-3-phosphate dehydrogenase. The results lend no support to such proposals, but show that the kinetic behaviour of the examined aldo