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Evolution of human immunodeficiency virus type 2 coreceptor usage, autologous neutralization, envelope sequence and glycosylation

To investigate why human immunodeficiency virus type 2 (HIV-2) is less virulent than HIV-1, the evolution of coreceptor usage, autologous neutralization, envelope sequence and glycosylation was studied in sequentially obtained virus isolates and sera from four HIV-2-infected individuals. Neutralization of primary HIV-2 isolates was tested by a cell line-based assay and IgG purified from patients'

Internal ecosystem feedbacks enhance nitrogen-fixing cyanobacteria blooms and complicate management in the Baltic Sea

Eutrophication of the Baltic Sea has potentially increased the frequency and magnitude of cyanobacteria blooms. Eutrophication leads to increased sedimentation of organic material, increasing the Extent of anoxic bottoms and subsequently increasing the internal phosphorus loading. In addition, the hypoxic water volume displays a negative relationship with the total dissolved inorganic nitrogen poo

New lower bound techniques for dynamic partial sums and related problems

We study the complexity of the dynamic partial sum problem in the cell-probe model. We give the model access to nondeterministic queries and prove that the problem remains hard. We give the model access to the right answer +/-1 as an oracle and prove that the problem remains hard. This suggests which kind of information is hard to maintain. From these results, we derive a number of lower bounds fo

Nuclear microprobe analysis of the selective boron uptake obtained with BPA in brain tumour tissue

The tumour selective ability of the boron compound boronophenylalanine (BPA), today used in Boron Neutron Capture Therapy in Sweden, has been investigated with the Lund Nuclear Microprobe. The tumour to tissue ratio of the boron concentration, as well as the location of boron within the cells, is critical for the efficiency of the therapy. It is desirable that the boron is accumulated as close as

Both food habit change in the past and obesity status may influence the association between dietary factors and postmenopausal breast cancer

Objective: Valid dietary data are essential when trying to identify whether or not one or more dietary exposures are responsible for disease. We examined diet composition in women who reported dietary change in the past compared with non-changers, and how the associations between dietary factors and postmenopausal breast cancer are influenced by dietary change, obesity status and misreporting of e

Immunomodulating activity of quinolones: review.

Fluorinated quinolones exert their bactericidal activity by inhibiting bacterial type II topoisomerases. At therapeutic concentrations, quinolones superinduce interleukin-2 (IL-2) and interferon-gamma production by mitogen-activated human peripheral blood T lymphocytes. At the molecular level, a stronger activation of the nuclear factor AP-1 ('activator protein-1') is observed in cells incubated w

Hyperfine structure and isotope shift of highly excited barium-I states

High-resolution laser-spectroscopy measurements of hyperfine structure and isotope shifts were performed for the 6snd 1 D 2 sequence of Ba-I in the regionn=12–24. Stepwise laser excitations of a collimated atomic beam were used. A strong influence on the hyperfine structure is observed at the perturbation atn=14, caused by interaction with the 5d7d configuration. Whereas the isotope shift for the

Coordinated system protection scheme against voltage collapse using heuristic search and predictive control

A coordinated system protection scheme (SPS) against voltage collapse based on model predictive control and tree search is presented. It optimally coordinates dissimilar and discrete controls such as generator, tap changer, and load shedding controls in presence of soft and hard constraints on controls as well as voltages and currents in the network. The response with the coordinated SPS is compar

Hormone replacement therapy: aspects of bleeding problems and compliance

Mitigation of vasomotor symptoms and urogenital problems, along with reductions in osteoporosis and cardiovascular disease, provides the rationale for using hormone replacement therapy (HRT), and the duration of use. However, user surveys have indicated poor compliance with HRT, and that means user time may be less than 12 months, a period unlikely to influence metabolic disorders. The main reason

Brood sex ratio adjustment in collared flycatchers (Ficedula albicollis): results differ between populations

Recently, a number of studies have found adaptive brood sex ratio (BSR) manipulation in birds. The reason for such manipulations is thought to be the different reproductive value of male and female nestlings. Several studies have found that parental quality and food supply can affect BSR, however results are sometimes inconsistent between species and populations. We investigated BSR patterns in a

Direct measurements of convective fluid velocities in superporous agarose beads

Superporous agarose beads contain two sets of pores, diffusion pores and so-called superpores or flow pores, in which the chromatographic flow can transport substances to the interior of each individual bead [Gustavsson and Larsson, J. Chromatogr. A 734 (1996) 231]. The existence of pore flow may be proven indirectly by the chromatographic performance of beads but it has never been directly demons

The Ups and Downs of the Holocene: Exploring Relationships between Global CO2 and Climate Variability in the North Atlantic Region

Popular Abstract in Swedish Jordens klimat har ändrats många gånger genom dess historia. Under de senaste 2,6 miljoner åren har de kontinentala landmassorna varit geografiskt fördelade på så sätt att relativt små skillnader i Jordens omloppsbana kring solen, s.k. orbitala förändringar, har givit upphov till övergångar mellan långvariga, kalla perioder (istider) och kortvariga, varma perioder (mellThis thesis aimed to examine the relationship between climate and atmospheric CO2 concentrations through rapid climate changes during the Holocene. Climate was reconstructed using high-resolution, radiocarbon dated, lake sediment geochemical proxies (magnetic susceptibility, loss-on-ignition, total carbon/nitrogen/sulphur determinations and biogenic silica), vegetational reconstruction (pollen ana

PHENIX detector overview

The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has prod

A randomized multicenter study to compare two treatment regimens of topical methyl aminolevulinate (Metvix (R))-PDT in actinic keratosis of the face and scalp

Photodynamic therapy (PDT) with topical methyl aminolevulinate ( MAL) administered in two treatment sessions separated by 1 week is an effective treatment for actinic keratoses. This open prospective study compared the efficacy and safety of MAL-PDT given as a single treatment with two treatments of MAL-PDT 1 week apart. Two hundred and eleven patients with 413 thin to moderately thick actinic ker

BRCA1 and BRCA2 mutation status and cancer family history of Danish women affected with multifocal or bilateral breast cancer at a young age

Introduction - A small fraction of breast cancer is the result of germline mutations in the BRCA1 and BRCA2 cancer susceptibility genes. Mutation carriers frequently have a positive family history of breast and ovarian cancer, are often diagnosed at a young age, and may have a higher incidence of double or multiple primary breast tumours than breast cancer patients in general. Objectives - To esti