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Isolation and characterization of two verrucarins from Myrothecium roridum

In the course of a screening for compounds inhibiting the growth of two human breast cancer cells lines, two highly cytotoxic compounds were isolated from fermentations of Myrothecium roridum. The elucidation of their structures revealed that they are macrocyclic trichothecenes of the verrucarin type, 16-hydroxyverrucarin A (1), reported here as a natural product for the first time, and verrucarin

Cost effectiveness of raloxifene in the treatment of osteoporosis in Sweden - An economic evaluation based on the MORE study

Background: The Multiple Outcomes of Raloxifene Evaluation (MORE) study showed that treatment with raloxifene reduces the risk of vertebral fracture and breast cancer in postmenopausal women with osteoporosis. Objective: Based on the MORE study the aim of the present study was to assess the cost effectiveness of raloxifene (compared with no treatment) for the treatment of osteoporosis in postmenop

Polarized light cues underlie compass calibration in migratory songbirds

Migratory songbirds use the geomagnetic field, stars, the Sun, and polarized light patterns to determine their migratory direction. To prevent navigational errors, it is necessary to calibrate all of these compass systems to a common reference. We show that migratory Savannah sparrows use polarized light cues from the region of sky near the horizon to recalibrate the magnetic compass at both sunri

Biologisk denitrifikation av dricksvatten - Biological denitrification of drinking water

A pilot-plant study, made to clarify whether biological denitrification is a possible and suitable method for nitrate reduction of drinking water in Sweden is presented. The concentration of nitrate-nitrogen in un-treated water was 10–15 mg/l. The reactor was a 1.2 m aluminium tube with a inner diameter of 0.19 m. 0.75 m was filled with Filtralite®, expanded clay, through which the nitrate-contami

Single-crystalline Ge grown epitaxially on oxidized and reduced Ge/Si(100) islands

In this paper, the Ge overgrowth of oxidized and reduced Ge/Si islands is studied. The islands were grown in a hotwall ultrahigh vacuum chemical vapour deposition reactor. The oxidation was performed in air at room temperature and the reduction in a hydrogen atmosphere at 600degreesC. After reduction, Ge was deposited at the same temperature. The results of the overgrowth show that the reduced nat

Breast cancer incidence in relation to smoking cessation

High plasma levels of oestrogens are associated with increased breast cancer risk. If smoking, as has been suggested, have both a tumour initiating mutagenic effect and a protective anti-oestrogenic effect, one would assume that smokers who give up smoking have the highest incidence of breast cancer. This was evaluated in the follow-up of a cohort of 10,902 women of whom 4,359 were premenopausal.

Trends of HIV-1 and HIV-2 prevalence among pregnant women in Guinea-Bissau, West Africa: possible effect of the civil war 1998-1999.

Objectives: Sentinel surveys in Bissau, the capital of Guinea-Bissau, have shown low prevalence of HIV-1 but high HIV-2 prevalence before 1998. Guinea-Bissau experienced a civil war in 1998-1999. To examine specifically the trends of HIV prevalence from antenatal surveys in Bissau, Guinea-Bissau in 1987-2004, and whether the civil war in 1998-1999 could have an effect on HIV prevalence levels afte

Effects of ambient UV-radiation on the behaviour of mayfly larvae of the genus Deleatidium from trout bearing and fishless streams in New Zealand

New Zealand ground levels of UV-radiation have always been comparatively high, however, little attention has been paid to the effects of UV-radiation on biotic interactions in New Zealand freshwater systems. In two outdoor short term microcosm experiments we tested the effects of UV-radiation on the behaviour of grazing mayfly Deleatidium (Ephemeroptera) larvae. The relationship between pigmentati

Chronic non-A, non-B, non-C hepatitis: is hepatitis G/GBV-C involved?

BACKGROUND: Hepatitis G virus/GBV-C is a recently discovered virus, and its relevance in chronic hepatitis is still debated. METHODS: We have previously described 127 long-term-studied and well-characterized patients with chronic non-A, non-B hepatitis (NANBH). Ninety-one (71.7%) were positive for hepatitis C virus antibodies (anti-HCV) in a first-generation anti-HCV enzyme-linked immunosorbent as

Temperature effect on single chain MEH-PPV spectra

We report single molecule photoluminescence spectra of poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) in PMMA-matrix at 293 and 20 K with 90 s acquisition time. All spectra at 293 K are very similar, contrary to literature results with acquisition times < 5 s. We propose that fluctuations of conformations with distinct emission properties cause broadening of the spectra and

Inelastic leptoproduction of J/psi mesons at HERA

The leptoproduction of J/psi mesons is studied in inelastic reactions for four momentorri transfers 2 < Q(2) < 100GeV(2). The data were taken with the H1 detector at the electron proton collider HERA and correspond to an integrated luminosity of 77 pb(-1). Single differential and double differential cross sections are measured with increased precision compared with previous analyses. New leading o

The influence of ventilation systems on water depth penetration of emergent macrophytes

1. Roots of emergent macrophytes depend on oxygen transported from aerial parts by diffusion and, in some species, by pressurised ventilation. The aim of this study was to determine if species with pressurised ventilation grow in deeper water in situ than species lacking this ability. 2. Species with pressurised ventilation grew significantly deeper than species lacking pressurised ventilation, an

Polarization measurements in neutral pion photoproduction

We present measurements of the recoil proton polarization for the H-1((γ) over right arrow,(p) over right arrow)pi(0) reaction for theta(c.m.)(pi) = 60degrees-135degrees and for photon energies up to 4.1 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. Various theoretical models are compared with the results. No evidence for hadron helicit

On the existence of harmonic morphisms from certain symmetric spaces

In this paper we give a positive answer to the open existence problem for complex-valued harmonic morphisms from the non-compact irreducible Riemannian symmetric spaces SLn (R)/SO(n), SU*(2n)/Sp(n) and their compact duals SU(n)/SO(n) and SU(2n)/Sp(n). Furthermore we prove the existence of globally defined, complex-valued harmonic morphisms from any Riemannian symmetric space of type IV.

The hoverflies (Diptera, Syrphidae) on a small farm at Linnaeus´ birthplace in the parish of Stenbrohult, Sweden

We made a detailed study of the hoverflies on a small farm in the parish of Stenbrohult, southern Sweden in 2004-2007. The study area is totally about 17 ha, consisting of 9 ha of semi-natural grasslands with both dry and wet parts (recently mainly grazed by cattle and a few horses in late summer-autumn), a few hectares of old deciduous forest dominated by Fagus, Quercus, Betula, Populus tremula,

Footwear for cold work: a field study at a harbour

A series of field studies at cold workplaces were initiated. This paper deals with a study at a harbour and the main attention is paid to the thermal responses of the feet and footwear performance. The study was carried out in February. Eight male workers were the subjects. They were selected among volunteers who carried out four different jobs in pairs. The warm winter boots were provided by the