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Poly(phenylene oxide) functionalized with quaternary ammonium groups via flexible alkyl spacers for high-performance anion exchange membranes

We have attached quaternary ammonium (QA) groups to poly(phenylene oxide) via flexible and stable heptyl side chains by using a straightforward synthetic route involving bromoalkylation and quaternization. Membranes based on these polymers showed efficient phase separation, significantly enhanced hydroxide ion conductivity and far superior alkaline stability in relation to corresponding polymers w

Preparation and Characterization of EVA/Clay Nanocomposites with Improved Barrier Performance

Poly (ethylene-co-vinyl acetate) (EVA)/clay nanocomposites containing two different organoclays with different clay loadings were prepared. The transport of gases (oxygen and nitrogen) through the composite membranes was investigated and the results were compared. These studies revealed that the incorporation of nanoclays in the polymer increased the efficiency of the membranes toward barrier prop

S100A9 expressed in ER(-)PgR(-) breast cancers induces inflammatory cytokines and is associated with an impaired overall survival.

Breast cancer is the most common cancer form among women today. Depending on hormone receptor status, breast cancers are divided into different subtypes with vastly varying prognosis. S100A9 is a calcium-binding protein that is associated with inflammation and expressed not only in myeloid cells but also in some tumours. The role for S100A9 in the malignant cells is not well characterised; however

Green Materialities: Marketing and the socio-material construction of green products

Green products are becoming part of contemporary consumer cultures and part of everyday life. But how are green products constructed? What kind of green products are constructed? And what happens as these green products are constructed? The aim of this paper is to contribute a socio-cultural and critical understanding of green marketing by exploring and illustrating how marketing practices work t

Polyethyleneimine-protein interactions and implications on protein stability

Protein stability assessment of seven model proteins in the presence of low molecular weight polyethyleneimine (PEI, MW 2000 Da) was performed. Thermodynamic stability, monitored by circular dichroism (CD) spectroscopy, showed that the polymer did not have a major effect on the melting temperature (T-m) of the basic proteins - muscle lactate dehydrogenase (LDH), ribonuclease A, lysozyme and cutina

Prognostic importance of atrial fibrillation in asymptomatic aortic stenosis: The Simvastatin and Ezetimibe in Aortic Stenosis study

Background: The frequency and prognostic importance of atrial fibrillation (AF) in asymptomatic mild-to-moderate aortic stenosis (AS) has not been well described. Methods: Clinical examination, electrocardiography and echocardiography were obtained in asymptomatic patients with mild-to-moderate AS and preserved left ventricular (LV) systolic function, randomized to simvastatin/ezetimibe combinatio

Social influence on route choice in a virtual reality tunnel fire

Introduction Evacuation from tunnel fire emergencies requires quick decision-making and swift action from the tunnel occupants. Social influence (SI) has been identified as an important factor in evacuation. Methods Two experimental groups were immersed into a virtual road tunnel fire. In the SI group participants saw a virtual agent moving on the shortest route to the nearest emergency exit. In

Genetic differentiation and admixture between sibling allopolyploids in the Dactylorhiza majalis complex.

Allopolyploidization often happens recurrently, but the evolutionary significance of its iterative nature is not yet fully understood. Of particular interest are the gene flow dynamics and the mechanisms that allow young sibling polyploids to remain distinct while sharing the same ploidy, heritage and overlapping distribution areas. By using eight highly variable nuclear microsatellites, newly rep

Analytical solutions to two- and three-dimensional periodic flows for numerical model testing

Analytical solutions to 2D depth-averaged (external mode) and fully 3D (internal mode) periodic flows for numerical model testing are presented in this paper. These solutions take into account the effects of the bottom friction, the horizontal turbulent viscosity, and the vertical turbulent viscosity for the case of 3D flow. The key linkage for the modes is the relationship between the bottom fric

Synthesis, characterization, and reactivity studies of heterodinuclear complexes modeling active sites in purple Acid phospatases.

To model the heterodinuclear active sites in plant purple acid phosphatases, a mononuclear synthon, [Fe(III)(H(2)IPCPMP)(Cl(2))][PF(6)] (1), has been generated in situ from the ligand 2-(N-isopropyl-N-((2-pyridyl)methyl)aminomethyl)-6-(N-(carboxylmethyl)-N-((2-pyridyl)methyl)amino methyl)-4-methylphenol (IPCPMP) and used to synthesize heterodinuclear complexes of the formulas [Fe(III)M(II)(IPCPMP)

Uniformity and diversity: A minimalist perspective

This essay discusses language uniformity and diversity in the light of recent development of the minimalist program (Hauser et al. 2002, Chomsky 2008, Berwick and Chomsky 2011, and much related work). It pursues two leading ideas. First, Universal Grammar (UG) is maximally minimal: hence early internal language (I-language) is largely uniform across individuals, language variation being mainly or

Fundamental nonlinearities of the reactor-settler interaction in the activated sludge process

The activated sludge process can be modelled by ordinary and partial differential equations for the biological reactors and secondary settlers, respectively. Because of the complexity of such a system, simulation models are most often used to investigate them. However, simulation models cannot give general rules on how to control a complex nonlinear process. For a reduced-order model with only two

Bioclimatic envelope model of climate change impacts on blanket peatland distribution in Great Britain

Blanket peatlands are rain-fed mires that cover the landscape almost regardless of topography. The geographical extent of this type of peatland is highly sensitive to climate. We applied a global process-based bioclimatic envelope model, PeatStash, to predict the distribution of British blanket peatlands. The model captures the present areal extent (Kappa = 0.77) and is highly sensitive to both te

Surface Properties of Nanocrystalline PbS Films Deposited at the Water-Oil Interface: A Study of Atmospheric Aging

Nanocrystalline thin films of PbS are obtained in a straightforward reaction by precipitation at the interface between toluene (containing a Pb precursor) and water (containing Na2S). Lead thiobiuret [Pb(SON(CN(i)Pr-2)(2))(2)] and lead diethyldithiocarbamate [Pb(S2CNEt2)(2)] precursors are used. The films are characterized by X-ray diffraction and electron microscopy, revealing typical particle si

Energy and Mass Exchange and the Productivity of Main Siberian Ecosystems (from Eddy Covariance Measurements). 2. Carbon Exchange and Productivity

Direct measurements of CO2 fluxes by the eddy covariance method have demonstrated that the examined middle-taiga pine forest, raised bog, true steppe, and southern tundra along the Yenisei meridian (similar to 90 degrees E) are carbon sinks of different capacities according to annual output. The tundra acts as a carbon sink starting from June; forest and bog, from May; and steppe, from the end of

pH Tolerance in Freshwater Bacterioplankton: Trait-Variation of the Community measured by Leucine Incorporation.

pH is an important factor determining bacterial community composition in soil and water. We have directly determined the community tolerance (trait variation) to pH in communities from 22 lakes and streams ranging in pH from 4 to 9 using a growth based method not relying on distinguishing between individual populations. pH in the water samples was altered to up to 16 pH values, covering in situ pH

Steam pretreatment and fermentation of the straw material "Paja Brava" using simultaneous saccharification and co-fermentation.

Pretreatment, enzymatic hydrolysis and simultaneous saccharification and fermentation (SSF) of the South American straw material Paja Brava were investigated. Suitable process conditions for an SO(2)-catalyzed steam pretreatment of the material were determined and assessed by enzymatic digestibility of obtained fiber slurries for 72h at a water insoluble solids (WIS) content of 2%. The best pretre

Higher Education Commons : a framework for comparison of midlevel units in higher education organisations

Socio-culturally formed collegial contexts in the midlevel of higher education organizations have attracted increased attention from higher education researchers. It is assumed that development, change and stability are dependent on norms, habits and traditions in these contexts. This text introduces a framework useful for identifying and investigating these collegial contexts. The framework is ap