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The effect of dominance on food hoarding: A game theoretical model

Many food hoarding animals live in small groups structured by rank. The presence of conspecifics in the hoarding area increases the risk of losing stored supplies. The possibility of stealing from others depends on a forager's rank in the group. Highly ranked individuals can steal from subordinates and also protect their own caches. Since storing incurs both costs and benefits, the optimal hoardin

Oxygen uptake rate measurements for evaluation of ozonation of municipal wastewater

Ozonation has become more frequently used as oxidant to reduce chemical oxygen demand (COD) and toxic substances in wastewater originating from different industrial processes. An ozonation pilot plant followed by two parallel biological filters are used to investigate the possibility to reduce the high concentration of refractory COD in the effluent from a municipal wastewater treatment plant, par

PKC and MAPK signalling pathways regulate vascular endothelin receptor expression

Up-regulation of vascular endothelin type A (ET(A)) and type B (ET(B)) receptors are implicated in the pathogenesis of cardiovascular disease. Culture of arteries has been shown to induce similar receptor alterations and has therefore been suggested as a suitable method for in detail delineation of the regulation of endothelin receptors. We hypothesize that protein kinase C (PKC) and mitogen-activ

Vision in the deep sea

The deep sea is the largest habitat on earth. Its three great faunal environments - the twilight mesopelagic zone, the dark bathypelagic zone and the vast flat expanses of the benthic habitat- are home to a rich fauna of vertebrates and invertebrates. In the mesopelagic zone (150-1000 in), the down-welling daylight creates an extended scene that becomes increasingly dimmer and bluer with depth. Th

Polybrominated diphenyl ether exposure to electronics recycling workers - a follow up study

Workers at an electronics recycling plant have previously been shown to have elevated serum levels of polybrominated diphenyl ethers (PBDEs) compared to referents without occupational PBDE exposure. Subsequent structural changes and industrial hygiene measures at the plant were applied to improve the work environment. The present study aims to assess the impact of these work environment changes on

Bridge splitting of trans-[PtCl2(C2H4)](2) by ethene using a simple combined NMR-UV/vis cell: Crystal and molecular structure of cis-[PtCl2(C2H4)(2)]

Bridge splitting of trans- [PtCl2(C2H4)](2) by C2H4 in chloroform yields trans-[PtCl2(C2H4)(2)] which slowly isomerises to cis[PtCl2(C2H4)(2)] (crystal structure reported); the bridge-splitting equilibrium constant was determined as 6.8 +/- 0.6 mol(-1) dm(3) by the use of a combined NMR tube/spectrophotometric cell, enabling NMR and UV/vis measurements on the same closed system. (C) 2006 Elsevier

Diversification of unicellular eukaryotes: cryptomonad colonizations of marine and fresh waters inferred from revised 18S rRNA phylogeny

The cryptomonads is a well-defined lineage of unicellular eukaryotes, composed of several marine and freshwater groups. However, the evolutionary relationships among these groups are unclear due to conflicting inferences between morphological and molecular phylogenies. Here, we have inferred the evolutionary relationships among marine and freshwater species in order to better understand the import

X-ray absorption and resonant Auger spectroscopy of O(2) in the vicinity of the O 1s-->sigma(*) resonance: Experiment and theory.

We report on an experimental and theoretical investigation of x-ray absorption and resonant Auger electron spectra of gas phase O(2) recorded in the vicinity of the O 1s-->sigma(*) excitation region. Our investigation shows that core excitation takes place in a region with multiple crossings of potential energy curves of the excited states. We find a complete breakdown of the diabatic picture for

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Abstract in German Die Bestimmung des prostataspezifischen Antigens (PSA) ist in der Frühdiagnostik des Prostatakarzinoms nach wie vor von zentraler Bedeutung. Ein ungelöstes Problem ist jedoch die geringe Spezifität dieses organ- aber nicht karzinomspezifischen Serummarkers, die bei einer hohen Anzahl von Patienten zu weiterer, dann invasiver Diagnostik führt, ohne dass ein Prostatakarzinom gefunDetection of prostate-specific antigen remains the mainstay in the early detection of prostate cancer. A problem yet unsolved is the lack of specificity of this organ- but not cancer-specific marker, which generates subsequent, invasive procedures in a high number of patients without detecting prostate cancer. While the separate detection of free PSA and the ratio of free to total PSA has signific

Long-Ranged Attractive Forces Induced by Adsorbed Dendrimers: Direct Force Measurements and Computer Simulations

Interaction forces between charged interfaces in the presence of oppositely charged dendrimers are studied by experiment and simulation. The experiments involve direct force measurements with all atomic force microscope (AFM) between two negatively charged colloidal particles in the presence of adsorbed, positively charged globular dendrimers. The simulations are carried out by treating the macroi

Welding process impact on residual stress and distortion

Residual stress and distortion continue to be important issues in shipbuilding and are still subject to large amounts of research. This paper demonstrates how the type of welding process influences the amount of distortion. Many shipyards currently use submerged arc welding (SAW) as their welding process of choice. In this manuscript, the authors compare welds made by SAW with DC gas metal arc wel

Fast correlation attacks through reconstruction of linear polynomials

The task of a fast correlation attack is to efficiently restore the initial content of a linear feedback shift register in a stream cipher using a detected correlation with the output sequence. We show that by modeling this problem as the problem of learning a binary linear multivariate polynomial, algorithms for polynomial reconstruction with queries can be modified through some general technique

The first neoceratopsian dinosaur remains from Europe

Shallow marine, nearshore strata of earliest Campanian (Gonioteuthis granulataquadrata belemnite Zone) and latest Early Campanian (informal Belemnellocamax mammillatus belemnite zone) age in the Kristianstad Basin, southern Sweden, have yielded isolated leptoceratopsid teeth and vertebrae, representing the first record of horned dinosaurs from Europe. The new leptoceratopsid occurrence may support

A mass spectrometry-based strategy for the direct detection and quantification of some mycotoxins produced by Stachybotrys and Aspergillus in indoor environments.

Dampness in buildings has been linked to adverse health effects, but the specific causative agents are unknown. Mycotoxins are secondary metabolites produced by molds and toxic to higher vertebrates. In this study, mass spectrometry was used to demonstrate the presence of mycotoxins predominantly produced by Aspergillus spp. and Stachybotrys spp. in buildings with either ongoing dampness or a hist

A 2048 complex point FFT processor using a novel data scaling approach

In this paper, a novel data scaling method for pipelined FFT processors is proposed. By using data scaling, the FFT processor can operate on a wide range of input signals without performance loss. Compared to existing block scaling methods, like implementations of Convergent Block Floating Point (CBFP), the memory requirements can be reduced while preserving the SNR. The FFT processor has been syn