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Popular Abstract in Swedish Att mäta och beskriva självantändning vid förblandad kompressionsantändning (HCCI) HCCI-förbränning går ut på att luft och bränsle blandas, och komprimeras i en kolvmotor tills blandningen självantänder. På grund av den snabba förbränningen med det här konceptet förloras mindre värmeenergi, och verkningsgraden blir därför högre än för vanliga bensin- och dieselmotorer. HCCI is an advanced combustion concept, using premixed fuel and air with a diluted charge. This is thermodynamically favorable, leading to high efficiency and therefore lower CO2 emissions. The well-premixed and diluted fuel charge gives lower cylinder temperatures than conventional diesel compression ignition and spark ignited gasoline combustion, resulting in low engine out emissions of both nit

In the past, neutron imaging investigations have been mostly performed in "integrating mode", which averages over the full applied neutron energy spectrum. This article describes four different methods and devices of obtaining energy selectivity in the thermal to cold energy range, which allow a new approach in neutron imaging. Two principles have been used and tested: (a) selection of neutrons by

Inconel 718 is a high strength, heat resistant superalloy that is used extensively for components in hot sections of gas turbine engines. This paper presents an experimental study on the thermal stability of broached Inconel 718 in terms of microstructure and nano-hardness. The broaching process used in this study is similar to that used in gas turbine industries for machining fir-tree root fixing

To describe contraceptive use and attitudes towards contraceptive use in Sweden which has the highest abortion rate in Western Europe. Secondary objectives were to investigate knowledge of contraceptive methods and outcomes of unplanned and unwanted pregnancies.

Objective : To measure the extent to which health-related quality of life (HRQoL) in people living with HIV is associated with duration of antiretroviral therapy (ART) after controlling for sociodemographic, clinical, and other therapy-related factors. Design : Cross-sectional analysis. Methods : A gender-stratified random sample of 421 participants aged 18-64 years was selected from the patients

Background: Malaria kills almost 1 million people every year, but the mechanisms behind protective immunity against the disease are still largely unknown. Methodology/Principal Findings: In this study, surface plasmon resonance technology was used to evaluate the affinity (measured as kd) of naturally acquired antibodies to the Plasmodium falciparum antigens MSP2 and AMA1. Antibodies in serum samp

30% of the DNA in E. coli bacteria is covered by proteins. Such a high degree of crowding affects the dynamics of generic biological processes (e.g. gene regulation, DNA repair, protein diffusion etc) in ways that are not yet fully understood. In this paper, we theoretically address the diffusion constant of a tracer particle in a one-dimensional system surrounded by impenetrable crowder particles

Water monomers and dimers have been studied at low temperatures in matrices of solid p-H(2), o-D(2), n-H(2), and n-D(2) using infrared spectroscopy. Our data demonstrate interaction mechanisms between host matrix and guest molecules that are different from the ones observed in atomic noble gas matrices. Notably both guest/host rotational-rotational interaction and matrix induced modifications of t

The fibrillation kinetics of the amyloid beta peptide is analyzed in presence of cationic polystyrene nanoparticles of different size. The results highlight the importance of the ratio between the peptide and particle concentration. Depending on the specific ratio, the kinetic effects vary from acceleration of the fibrillation process by reducing the lag phase at low particle surface area in solut

The map is not simply a representation of existing space, or a mirror of the earth’s surface. It is rather a multi-faceted instrument expressing that the power to represent is the power to order, and that the rationality of geometrical space could influence people’s lived spaces through its role as a planning tool. These issues are discussed with three examples from Swedish modernity; the producti

Coordination of apical constriction in epithelial sheets is a fundamental process during embryogenesis. Here, we show that DRhoGEF2 is a key regulator of apical pulsation and constriction of amnioserosal cells during Drosophila dorsal closure. Amnioserosal cells mutant for DRhoGEF2 exhibit a consistent decrease in amnioserosa pulsations whereas overexpression of DRhoGEF2 in this tissue leads to an

Objective: To determine whether preterm birth is associated with epilepsy in a national cohort of adults aged 25-37 years. Methods: We conducted a national cohort study of 630,090 infants born in Sweden from 1973 through 1979, including 27,953 born preterm (< 37 weeks), followed from 2005 to 2009 for 1) hospitalization for epilepsy and 2) outpatient and inpatient prescription of antiepileptic drug

Overwash is the flow of water and sediment over the crest of a beach system when the runup level of waves or the water level, often enhanced by storm surge, exceeds the local beach or dune crest height. The impacts of overwash on coastal barriers or low lying mainland coasts are striking. Overwash may cause deposition of sand on and landward of the beach crest, large fan shaped deposits on back ba

A new method to accurately estimate the interaction energy between a large molecule and a smaller ligand is presented. The method approximates the electrostatic and induction contributions classically by multipole and polarizability expansions, but uses explicit quantum-mechanical fragment calculations for the remaining (nonclassical) contributions, mainly dispersion and exchange repulsion. Thu

Fluence-response curves were obtained at nine wavelengths in the interval 280--360 nmformRNAtranscripts of four molecular markers induced by ultraviolet-B (UV-B) radiation in Arabidopsis thaliana (L.) Heynh.: CHS (encoding chalcone synthase), PDX1.3 (encoding an enzyme involved in formation of pyridoxine), MEB5.2 (encoding a protein with unknown function but which is strongly upregulated by UV-B),

Aims. The detection and measurement of gravitational-waves from coalescing neutron-star binary systems is an important science goal for ground-based gravitational-wave detectors. In addition to emitting gravitational-waves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to th

Block copolymers dissolved in selective solvent often self-assemble. We review the use of NMR to Study this process and to characterize the aggregates formed. We stress the need to consider the polydispersity of the polymers and the fact that the increase in NMR relaxation rates observed upon aggregation can be assigned to contributions from the block copolymer micelle tumbling. (C) 2008 Elsevier