Amphibian larvae often face two major sources of mortality: pond desiccation and predation. Tadpoles of seven anuran species with different preferences for type of breeding habitat, on a hydroperiod scale, were tested for responses to the presence of predators by raising them experimentally in the presence and absence of a separately caged invertebrate predator that was fed on conspecific tadpoles

From an extract of the stem bark of Xymalos monospora, a bis-benzylisoquinoline alkaloid (1), three benzylisoquinoline alkaloids (mollinedine, 1-(p-methoxybenzyl)-6,7-methylenedioxyisoquino-line, doryafranine), and an aporphine alkaloid (N-methyllaurotetanine) were isolated. These compounds were tested for growth inhibitory activity against bloodstream forms of three strains of African trypanosome

Along with rapidly developing nanotechnology, new types of analytical instruments and techniques are needed. Here we report an alternative procedure for electrical measurements on semiconductor nanowhiskers, allowing precise selection and visual control at close to atomic resolution. We use a combination of two powerful microscope techniques, scanning tunneling microscopy (STM) and simultaneous vi

Objective. To investigate work disability rates over 15 years in an early rheumatoid arthritis (RA) cohort and to evaluate predictive factors during the course of the study. Methods. All patients with early RA of working age (n = 148) were followed and treated at a team care unit. Mean disease duration at inclusion was 1 year. Work characteristics and disease-related variables were recorded annual

Anesthetized, paralyzed and mechanically ventilated pigs were exposed to extreme hypercapnia (PaCO2 approximately 20 kPa) at FiO2 0.4 for 480 min, with (n = 6) or without (n = 6) continuous infusion of isotonic buffers (bicarbonate and trometamol). Arterial pH was higher in buffered animals than controls, 7.21 +/- 0.01 vs 7.01 +/- 0.01 (mean +/- s.e.mean, P < 0.01). Serum osmolality and PaCO2 did

The Sorvik granite occurs as rounded massifs in the Revsund granite in central Sweden. The rock is medium-grained with rounded quartz crystals ('drop quartz') and occasional, sometimes albiterimmed megacrysts of K-feldspar. It is a faintly peraluminous 1-type granite with some A-type affinities showing a limited chemical variation. The SiO2 content normally varies between 68 and 77 weight%. The ro

1. Recent changes in European agricultural policy have led to measures to reverse the loss of species-rich grasslands through the creation of new areas on ex-arable land. Ex-arable soils are often characterized by high inorganic nitrogen (N) levels, which lead to the rapid establishment of annual and fast-growing perennial species during the initial phase of habitat creation. The addition of carbo

The toxicity of different phenols to the soil bacterial community was studied in the laboratory using the leucine incorporation technique. The effects of environmental factors such as pH, temperature and binding strength to soil particles were also assessed in order to deduce confounding effects due to the chemical and physical conditions in the soil from which the bacterial community was extracte

BACKGROUND: Diagnosis with prostate cancer has been reported to increase the risk of subsequent tumours. However, specific data on individuals with a parental history are not available so far. METHODS: On the basis of the nationwide Swedish Family-Cancer Database including 18,207 primary invasive prostate cancers, standardised incidence ratios (SIRs) were used to estimate the relative risks of sub

Stereoselectivity has been known to play a role in drug action for 100 years or more. Nevertheless, chiral drugs have been developed and used as racemates, neglecting the fact that they comprise mixtures of two or more compounds which may have quite different pharmacological properties. A very limited access to pure enantiomers in the past has been responsible for this unsatisfactory state of affa

The folding kinetics of bovine acyl-CoA binding protein was studied by N-15 relaxation dispersion measurements under equilibrium conditions. Relaxation dispersion profiles were measured at several concentrations of guanidine hydrochloride (GuHCl). The unfolding rate constant (k(u)) was determined under conditions favoring folding, for which the folding rate constant (k(f)) dominates the relaxation

Using Bloch waves to represent the full solution of Maxwell's equations in periodic media, we study the limit where the material's period becomes much smaller than the wavelength. It is seen that for steady state fields, only a few of the Bloch waves contribute to the full solution. Effective material parameters can be explicitly represented in terms of dyadic products of the mean values of the no

The thermophilic bacterium Rhodothermus marinus produces a modular xylanase (Xyn10A) consisting of two N-terminal carbohydrate-binding modules (CBMs), followed by a domain of unknown function, and a catalytic module flanked by a fifth domain. Both Xyn10A CBMs bind calcium ions, and this study explores the effect of these ions on the stability of the full-length enzyme. Xyn10A and truncated forms t