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Complexation, phase separation, and redissolution in polyelectrolyte-macroion solutions

The complexation, phase separation, and redissolution of polyelectrolyte-macroion solutions have been studied by means of Monte Carlo simulations. A simple model system with focus on the electrostatic interactions has been used to examine the properties of the macroion solutions at different amounts of oppositely charged polyelectrolytes. As oppositely charged polyelectrolytes are added, the stabl

Fuel cell membrane materials by chemical grafting of aromatic main-chain polymers

An extensive world-wide pursuit for new efficient fuel cell membranes materials is currently motivating research on proton-conducting ionomers based on durable aromatic main-chain polymers. In this context, most ionomers. have been prepared either by direct sulfonation of polymers, using for example. fuming. sulfuric-acid, or by direct polymerizations using different sulfonated monomers, Far less

Hokupa'a anisoplanatism and Mauna Kea turbulence characterization

A data set of adaptive optics images has been analyzed in order to study the effects of angular anisoplanatism and to characterize Mauna Kea nighttime turbulence. The data set consists of a selection of Galactic center images obtained with the adaptive optics instrument Hokupa'a and the near-infrared camera QUIRC on the Gemini-North 8 m telescope. Using the Strehl ratio and the FWHM as tracers for

Low temperature anaerobic digestion of mixtures of llama, cow and sheep manure for improved methane production

Biogas production in anaerobic digestion in farm-scale units is typically performed under mesophilic conditions when used for producing domestic fuel and stabilizing animal waste for the use of digested manure as a fertilizer. Previous studies on the digestion of llama and cow manure have shown the feasibility of producing biogas under altiplano conditions (low pressure and low temperature) and of

Bacillus bogoriensis sp nov., a novel alkallphilic, halotolerant bacterium isolated from a Kenyan soda lake

Strain LBB3(T) isolated from Bogoria soda lake in Kenya is an alkaliphilic, Gram-positive, strictly aerobic, non-motile, spore-forming bacterium. It was identified as a member of the genus Bacillus on the basis of phenotypic and phylogenetic analyses. The organism grows optimally at 37 degrees C and pH 10. The G+C content of the genomic DNA is 37.5 mol%. 16S rRNA gene sequence analysis showed 95 a

Integrated bioprocess for the production and isolation of urokinase from animal cell culture using supermacroporous cryogel matrices

An integrated cell cultivation and protein product separation process was developed using a new type of supermacroporous polyacrylamide gel, called cryogel (pAAm-cryogel) support matrix. Human fibrosarcoma HT1080 and human colon cancer HCT116 cell lines were used to secrete urokinase (an enzyme of immense therapeutic utility) into the culture medium. The secreted protein was isolated from the circ

Can An "Estimation Factor" Help Explain Cross-Sectional Returns?

We show in a theoretical model that the expected excess return on any asset depends on its covariance not only with the market portfolio, but also with changes in the representative agent's estimate. We test our model by using GMM and compare it to the CAPM. The results suggest that adding an "estimation factor" to the CAPM helps in explaining cross-sectional returns and that, unconditionally, thi

Leafing phenology and timing of egg laying in great tits Parus major and blue tits P-caeruleus

To evaluate the importance of tree leafing for the start of laying and clutch size of birds, we compared the breeding phenology of great tits Parus major and blue tits P. caeruleus between one coastal and two inland sites in the same geographical region. Because of the cooling influence of the sea, trees at the coastal site were known to initiate budburst about a week later than at the inland site

Diffusion-weighted imaging of brain metastases: their potential to be misinterpreted as focal ischaemic lesions.

Small focal ischaemic brain lesions are said to be easy to identify in the acute stage and to differentiate from older lesions using diffusion-weighted imaging (DWI). Brain metastases are common and the aim of this study was to evaluate the risk of misinterpretation as ischaemic lesions in a standard MRI protocol for clinical stroke. Of 26 patients investigated with MRI for possible metastases, 12

Vertical wrap-gated nanowire transistors

We present a process for fabricating a field-effect transistor based on vertically standing InAs nanowires and demonstrate initial device characteristics. The wires are grown by chemical beam epitaxy at lithographically defined locations. Wrap gates are formed around the base of the wires through a number of deposition and etch steps. The fabrication is based on standard III - V processing and inc

Assessment of the impacts of climate change and weather extremes on boreal forests in northern Europe, focusing on Norway spruce

The boreal and boreo-nemoral forests in Europe, which occur in northern and northeastern Europe, are dominated by 2 coniferous species, Norway spruce Picea abies (L.) Karst. being economically the most important one. Forestry is of major economic importance in this region. Forestry planning and climate change scenarios are based on similar (long-term) timescales, i.e. between 70 and 120 yr. Within

Curli, fibrous surface proteins of Escherichia coli, interact with major histocompatibility complex class I molecules

Curli are thin, coiled fibers expressed on the surface of Escherichia coli that bind several matrix and plasma proteins such as fibronectin, laminin, plasminogen, tissue plasminogen activator, and H-kininogen. In this work, we examined the interactions between curli-expressing E. coli and human major histocompatibility complex class I (MHC-I) and class II (MHC-II) molecules. Curliated E. coli was

Neck muscle vibration alters visually-perceived roll after unilateral vestibular loss

Unilateral sternocleidomastoid muscle vibration was applied to 21 normal and six unilateral vestibular deafferented (uVD) human subjects at head erect and during 30 degrees left and right whole body roll-tilt. In normal subjects, neck vibration had no effect upon the settings of a visual bar to subjective visual horizontal (SVH) in any roll-tilt condition. In uVD subjects settings to SVH were sign

Spin-polarized electron tunneling across a Si delta-doped GaMnAs/n-GaAs interface

We study the spin-polarized tunneling of electrons from the valence band of GaMnAs into the conduction band of n-type GaAs with Si delta-doping at the interface. The injection of spin-polarized electrons is detected as circular polarized emission from a GaInAs/GaAs quantum well light emitting diode, corresponding to magneto-optical Kerr effect loops. The angular momentum selection rules are simpli