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On the correlation between heterozygosity and fitness in natural populations

Three primary hypotheses currently prevail for correlations between heterozygosity at a set of molecular markers and fitness in natural populations. First, multilocus heterozygosity- fitness correlations might result from selection acting directly on the scored loci, such as at particular allozyme loci. Second, significant levels of linkage disequilibrium, as in recently bottlenecked-and-expanded

Male-biased gene flow across an avian hybrid zone: evidence from mitochondrial and microsatellite DNA

Mating pattern and gene flow were studied in the contact zone between two morphologically very similar Chiffchaff taxa (Phylloscopus collybita, P. brehmii) in SW France and northern Spain. Mating was assortative in brehmii, but not in collybita. Mixed matings were strongly asymmetric (excess of callybita male x brehmii female pairs), but did produce viable offspring in some cases. Sequence diverge

Recombinant horseradish peroxidase- and cytochrome c-based two-electrode system for detection of superoxide radicals

The reliable detection of a superoxide anion radical O-2(.-) - is complicated by its spontaneous dismutation reaction to H2O2 at acidic pHs. To simultaneously detect both O-2(.-) and H2O2 produced in the course of its spontaneous dismutation, an electrochemical two-electrode system based on cytochrome c (cyt c) and recombinant horseradish peroxidase (rHRP) was applied. Therewith, a limited applica

On preprocessing of protein sequences for neural network prediction of polyproline type II secondary structures

Polyproline type II stretches are somewhat rare on proteins. The backbone of this secondary structural element folds to a triangular form instead of the normal alpha -helix with 3.6 residues per turn. It is a very challenging task to try to detect them computationally from protein sequence. Here, we have studied the preprocessing phase in particular, which is important for any machine learning met

Recent developments in clinimetric instruments

Assessment of impairment and function is essential in order to monitor joint status and evaluate therapeutic interventions in patients with haemophilia. The improvements in the treatment of haemophilia have required the development of more sensitive tools to detect the more minor dysfunctions that may now be apparent. This paper outlines some of the recent developments in this field. The Haemophil

Ectopic expression of PAX5 promotes self renewal of bi-phenotypic myeloid progenitors co-expressing myeloid and B-cell lineage associated genes.

The transcription factor PAX5 is a critical regulator of B-cell commitment and development. Although normally not expressed in myeloid progenitors, PAX5 has recently been shown to be frequently expressed in myeloid malignancies and to suppress expression of myeloid differentiation genes, compatible with an effect on the differentiation or maintenance of myeloid progenitors. However, previous studi

The reaction of monoclonal antibodies with hordeins from five different Hordeum species.

Hordeins from H. vulgare, H. murinum, H. pusillum, H. bulbosum, and H. brevisubulatum were probed with five monoclonal antibodies raised against different hordein polypeptides from Hordeum vulgare cv. ‘Bomi’. The response pattern differed widely among species. One of the antibodies, CMpBChorl, was found to react with hordein from every tested species, and all of the antibodies reacted with at leas

The role of p-c-Jun in survival and outgrowth of developing sensory neurons

c-jun activation has been implicated not only in neuronal apoptosis, but also in survival and regeneration. This Janus facet of c-Jun activation could be related to neuronal cell type or to the developmental stage of the neuron. We investigated c-Jun activation in E18 sensory neurons. Cultures of rat dorsal root ganglia neurons were maintained with or without the addition of nerve growth factor or

Embedding point sets into plane graphs of small dilation

Let S be a set of points in the plane. What is the minimum possible dilation of all plane graphs that contain S? Even for a set S as simple as five points evenly placed on the circle, this question seems hard to answer; it is not even clear if there exists a lower bound >1. In this paper we provide the first upper and lower bounds for the embedding problem. 1. Each finite point set can be embedded

Screen-printed multienzyme arrays for use in amperometric batch and flow systems

Screen-printing technology for electrode fabrication enables construction of amperometric devices suitable for combination of several enzyme electrodes. To develop a biosensor array for characterisation of wastewaters, tyrosinase and horseradish peroxidase (HRP) or cholinesterase-modified electrodes were combined on the same array. The behaviour of the tyrosinase-modified electrode in the presence

Begging affects parental effort in the pied flycatcher, Ficedula hypoleuca

It has been suggested that nestlings use begging to increase their share of parental resources at the expense of current or future siblings. There is ample evidence that siblings compete over food with nestmates by begging, but only short-term effects of begging on parental provisioning rates have been shown. In this study, we use a new experimental design to demonstrate that pied flycatcher (Fice

The Protective Association of High Plasma Enterolactone with Breast Cancer Is Reasonably Robust in Women with Polymorphisms in the Estrogen Receptor alpha and beta Genes

It is plausible that polymorph isms in the estrogen receptor alpha and beta genes (ESR1 and ESR2) may modulate the association between enterolactone and breast cancer. Seven polymorph isms in ESR1 (rs827422, rs1709184, rs2347867, rs3020328, rs72207, rs2982896, and rs2234693) and 5 polymorphisms in ESR2 (rs915057, rs1269056, rs1256033, rs3020450, and rs3020443) were selected. The risk of breast can

Characterization of a continuous supermacroporous monolithic matrix for chromatographic separation of large bioparticles

A continuous supermacroporous monolithic chromatographic matrix has been characterized using a capillary model, experimental breakthrough curves, and pressure drop experiments. The model describes the convective flow and its dispersive mixing effects, mass transfer resistance, pore size distribution, and the adsorption behavior of the monolithic matrix. It is possible to determine an effective por

Expression of respiratory mucins in fatal status asthmaticus and mild asthma

Aims: The airways of patients with asthma are characterized by chronic inflammatory changes comprising mainly T-cells and eosinophils, and airway remodelling with goblet cell metaplasia and submucosal gland hyperplasia. Mucus hypersecretion is often a marked feature, particularly in status asthmaticus. The matrix of airway sputum consists of high molecular glycoproteins and mucins. In this study,