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Porous polymaleimide networks

Porous network structures were prepared by in situ polymerisation of a mixture of N-phenylmaleimide and 1, 1'-(methylenedi-4,1-plienylene)bismaleimide (95:5 w/w) in poly(vinylidene difluoride-co-hexafluoropropylene) (PVDH). The mixture of the maleimide monomers was found to form thermoreversible gels with PVDH. Thermodynamic analysis of the gelation process using calorimetry data indicated the for

Older pedestrians’ perceptions of the outdoor environment in a year-round perspective

This paper focuses on older peoples’ needs as pedestrians by examining their perceptions of the outdoor environment in both bare-ground and snow/ice conditions. Qualitative and quantitative methods are used, including focus group interviews, participant observations, and questionnaires. The results show that older people consider accessibility/usability issues as very important and that the import

Fracture mechanics analysis of microcracks in thermally cycled thermal barrier coatings

The effects from thermal shock loading on pre-existing microcracks within thermal barrier coatings (TBCs) have been investigated through a finite element based fracture mechanical analysis. The TBC system consists of a metallic bond coat and a ceramic top coat. The rough interface between the top and bond coats holds an alumina oxide layer. Stress concentrations at the interface due to the interfa

Carbon nanorings: A challenge to theoretical chemistry

High-level quantum-chemical methods show that the binding in the inclusion complex of hexamethylbenzene (HMB) in 6-cycloparaphenitacetylene (6-CPPA) cannot be explained only in terms of electrostatic interactions-caused by the polarization associated to curved a-conjugated systems-and the inclusion of dispersion forces is definitely needed. The theoretical description of van der Wools interactions

Linkage mapping reveals sex-dimorphic map distances in a passerine bird

Linkage maps are lacking for many highly influential model organisms in evolutionary research, including all passerine birds. Consequently, their full potential as research models is severely hampered. Here, we provide a partial linkage map and give novel estimates of sex-specific recombination rates in a passerine bird, the great reed warbler (Acrocephalus arundinaceus). Linkage analysis of genot

Cryptanalysis of Achterbahn

We present several attacks against the Achterbahn stream cipher, which was proposed to the eSTREAM competition. We can break the reduced and the full version with complexity of 2 55 and 2 61 steps. Extensions of our attacks are also described to break modified versions of the Achterbahn stream cipher, which were proposed following the publication of preliminary cryptanalysis results. These attacks

An X-ray absorption and photoemission study of the electronic structure of Ni porphyrins and Ni N-confused porphyrin

Investigations of chemical bonding and electronic structure features for polycrystalline (porphyrinato)nickel (II) (NiP, the simplest Ni porphyrin), (5,10,15,20-tetraphenylporphyrinato)nickel (II) (NiTPP) and (2-aza-21-carba-5,10,15,20-tetraphenylporphyrinato)nickel (II) (N-confused NiTPP, NiNCTPP) have been performed by means of high-resolution soft x-ray absorption and x-ray photoemission spectr

Stromal cell-derived inducing activity does not promote dopaminergic differentiation, but enhances differentiation and proliferation of neural stem cell-derived astrocytes.

Previous evidence has shown that stromal cell-derived inducing activity (SDIA), produced by the mouse PA6 stromal cell line, promotes dopaminergic differentiation of mouse, monkey and human embryonic stem cells in vitro. To examine whether PA6 stromal cells can enhance the yield of dopaminergic differentiation from neural progenitors, we generated neurospheres from embryonic day 11.5 (E11.5) (midb

Att sminka de döda

Mitt paper handlar om den amerikanska tv-serien Six Feet Under, och i fokus för min framställning står berättelsens behandling av föreställningar om döden som knuten till naturen och som något ”naturligt” – satt i relation till kultur och estetik. I Six Feet Under behandlas en rad ämnen centrala för det västerländska samhällets diskurser om natur, kultur, moral och existens. Serien fick ett stort

Bird or bat: comparing airframe design and flight performance.

Birds and bats have evolved powered flight independently, which makes a comparison of evolutionary 'design' solutions potentially interesting. In this paper we highlight similarities and differences with respect to flight characteristics, including morphology, flight kinematics, aerodynamics, energetics and flight performance. Birds' size range is 0.002-15 kg and bats' size range is 0.002-1.5 kg.

Smoking and lymphoma risk in the european prospective investigation into cancer and nutrition

Lymphomas are one of the few cancers that have been increasing in incidence over the past decades. So far, only a few established risk factors have been identified, including immunosuppression and viral infections. Recent evidence suggests etiologic heterogeneity of different lymphoma subtypes. Smoking may affect risk differently, depending on the lymphoma entity. The European Prospective Investig

Influence of humic substances on bacterial and viral dynamics in freshwaters

Bacterial and viral abundances were measured in 24 lakes with dissolved organic carbon (DOC) concentrations ranging from 3 to 19 mg of C liter(-1). In addition, a laboratory experiment was performed to test the effects of different sources of carbon (i.e., glucose and fulvic acids) and nutrients on the dynamics of viruses and bacteria. In the lake survey, no correlation was found between virus abu

Selective antiproliferative activity of hydroxynaphthyl-beta-D-xylosides

The antiproliferative activity of the 14 isomeric monoxylosylated dihydroxynaphthalenes has been tested in vitro toward normal HFL-1 and 3T3 A31 cells as well as transformed T24 and 3T3 SV40 cells. The antiproliferative effect toward HFL-1 cells was correlated with the polarity of the compounds. However, in the case of transformed T24 cells, some compounds showed a clearly different behavior resul

Behavioral interference and facilitation in the foraging cycle shape the functional response

Individual forager behaviors should affect per capita intake rates and thereby population and consumer-resource properties. We consider and incorporate conspecific facilitation and interference during the separate foraging-cycle stages in a functional response model that links individual behavioral interactions with consumer-resource processes. Our analyses suggest that failing to properly conside

Functional activity of the complement regulator encoded by Kaposi's sarcoma associated herpesvirus.

Kaposi's sarcoma-associated herpesvirus (KSHV) is closely associated with Kaposi's sarcoma and certain B-cell lymphomas. The fourth open reading frame of the KSHV genome encodes a protein (KSHV complement control protein (KCP, previously termed ORF4)) predicted to have complement-regulating activity. Here, we show that soluble KCP strongly enhanced the decay of classical C3-convertase but not the

Food webs in sub-Antarctic lakes: a stable isotope approach

In order to improve the understanding of food-web interactions in sub-Antarctic freshwater systems, we complemented earlier experimental studies with analyses of differences in stable isotopes (N-15 and C-13) among organisms in two lakes with contrasting productivity. The distribution of the stable isotopes showed that the small copepod Boeckella michaelseni feeds mainly on pelagic POM (particulat

Poly(beta-hydroxybutyrate) production by a moderate halophile, Halomonas boliviensis LC1

The moderate halophile Halomonas boliviensis, isolated from a Bolivian saline soil sample, was able to accumulate poly(P-hydroxybutyrate) (PHB) when grown under conditions of nutrient limitation and excess carbon source. The concentration of sodium chloride in the medium influenced the cell-growth, -size, and rate of PHB accumulation. Cultivation in shake flasks led to a PHB accumulation of about

The hyphal and yeast forms of Candida albicans bind the complement regulator C4b-binding

Candida albicans, an important pathogenic yeast, activates all three pathways of the complement system. To understand how this yeast evades the effects of the activated system, we have analyzed the binding of the classical pathway inhibitor C4b-binding protein (C4BP) by C. albicans. Purified native as well as recombinant C4BP bound dose dependently to the yeast and hyphal forms, as shown by multip