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Low complexity Rake receivers in ultra-wideband channels

One of the major issues for the design of ultra-wideband (UWB) receivers is the need to recover the signal energy dispersed over many multipath components, while keeping the receiver complexity low. To this aim we consider two schemes for reduced-complexity UWB Rake receivers, both of which combine a subset of the available resolved multipath components. The first method, called partial Rake (PRak

Simulation of two-phase flow in a heat exchanger distributor application

In this work, compulations of the air/water flow in a distributor were completed with the FLUENT two-phase VOF model and compared to experiments. The parameters of interest concerned the ratio between the deflected mass flow rate of the water phase to the mass flow rate of the water phase at the inlet called the deflection ratio as well as the recreation of the flow pattern of the different two-ph

Plasticity in pigmentation induced by conflicting threats from predation and UV radiation

In a variable and unpredictable environment, phenotypic plasticity in morphology or behavior may considerably improve an organism's protection against environmental threats and thereby its fitness. Here I demonstrate that common freshwater organisms, copepods (Crustacea), show a plastic response by adjusting pigmentation level in relation to two environmental threats: ultraviolet radiation (UV) an

Reported treatment of hypercholesterolemia by family physicians in Sweden and Minnesota

Swedish guidelines on treatment of hyperlipidemia recommend higher cut-off levels for initiating treatment than do American guidelines, but are virtually identical for instituting and performing therapy. The aim of this study was to compare family physicians' reported practices in Sweden and Minnesota. We selected random samples of family physicians in southern Sweden and Minnesota for telephone i

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