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Environmental fluctuations have been proposed to enhance the coexistence of competing phenotypes. Evaluations are here presented on the effects of prey density and short-term temporal clumping of prey availability on the relative foraging success of unequal interferers in social forager groups of juvenile brown trout Salmo trutta feeding on drifting invertebrate prey (frozen chironomids). Groups o

Some recent sexual selection models predict that female choice in species without paternal care may function to discriminate among males in order to pass ''good genes'' to offspring. Data quantifying the relationship between female mate choice and reproductive success are scarce. In a Swedish population of pheasants females prefer to mate with long-spurred males. Male viability also correlates wit

Research in avian blood parasites has seen a remarkable increase since the introduction of polymerase chain reaction-based methods for parasite identification. New data are revealing complex multihost-multiparasite systems which are difficult to understand without good knowledge of the host range and geographical distribution of the parasite lineages. However, such information is currently difficu

Nine palynological intervals, A-I in ascending order, are recognised in the Carboniferous succession of the well 7120/2-1 on the Loppa High in the western Barents Sea. Within the Billefjorden Group intervals A-E are correlated with the early Visean to Serpukhovian Pu to TK Miospore Zones of western Europe. The known sedimentation break between the Billefjorden and Gipsdalen groups occurred in the

Three xylose isomerase enzymes (XI) [Eur. J. Biochem. 269 (2002) 157], encoded by mutated xylA genes from Thermus thermophilus, were produced at two different levels in Saccharomyces cerevisiae; xylA genes were chromosomally integrated and expressed from multicopy plasmids, respectively. An extra copy of the endogenous xylulokinase gene (XKS1) was chromosomally integrated and the aldose reductase

This paper explores the options that can be used by aid organizations working in human settlement development to more effectively address disaster risk management. Qualitative research was carried out in El Salvador at both the household and institutional levels - to analyze the needs, capacities and perspectives of slum dwellers and aid organizations. A clearer understanding of the gaps between w

The synthesis and characterisation of supramolecular model systems mimicking the light reactions on the donor side of Photosystem II (PSII) in green plants have been reviewed. In these systems, manganese complexes and tyrosine are electron donors, modelling the manganese cluster and tyrosineZ in PSII. The donors have been covalently linked to a photosensitizer, a ruthenium(ii) tris-bipyridyl compl

Objectives: The aim of this study was to analyze the effect of longstanding nicotine exposure on bone healing and osseointegration of titanium implants. Materials and Methods: 20 female rabbits received either nicotine (n = 10) or saline (n = 10) administered subcutaneously via mini-osmotic pumps for 32 weeks. The pump delivered 6 mu g/kg/min of nicotine for the animals in the test group. Blood sa

We investigate the existence of solutions to first-order ordinary differential equations that asymptotically approach a prescribed function. Conditions for existence are given that relate the equation to a similar equation for the prescribed function. (c) 2006 Elsevier Ltd. All rights reserved.

Abstract The circular distribution of the willow warbler Phylloscopus trochilus around the Baltic Sea shares many features with the classic examples of ring species; however, the system is much younger. It has previously been shown that a secondary contact zone is located in central Scandinavia, where there are narrow clines for several morphological traits coincident with a migratory divide. Here

The most precise method of investigating possible space-time variations of the fine-structure constant, alpha equivalent to (1/hc)(e(2)/4 pi epsilon(0)), using high-redshift quasar absorption lines is the many-multiplet (MM) method. For reliable results this method requires very accurate relative laboratory wavelengths for a number of UV resonance transitions from several different ionic species.

Functional recovery following intrastriatal transplantation of fetal dopaminergic neurons in animal models of Parkinson's disease is, at least in part, dependent on the number of surviving dopaminergic neurons and the degree of graft-derived dopaminergic reinnervation of the host striatum. In the present study, we analyzed whether continuous exposure of glial cell line-derived neurotrophic factor

Global gene expression profiling of highly purified 5q-deleted CD34(+)CD38(-)Thy1(+) cells in 5q(-) myelodysplastic syndromes (MDSs) supported that they might originate from and outcompete normal CD34(+)CD38(-)Thy1(+) hematopoietic stem cells. Few but distinct differences in gene expression distinguished MDS and normal stem cells. Expression of BMI1, encoding a critical regulator of self-renewal,