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Ion-exchange macroporous hydrophilic gel monolith with grafted polymer brushes

The grafting of functional polymers to the pore surface of macroporous monolithic polyacrylamide cryogels was found to be an efficient and convenient method for the preparation of macroporous polyacrylamide gels, so-called cryogels (pAAm cryogels), with both controlled extent of functional group incorporated and with tailored surface chemistries. Anion-exchange polymer chains of poly(2-(dimethylam

beta-Casein adsorption at the silicon oxide-aqueous solution interface: Calcium ion effects

Neutron reflectometry was used to investigate effects of calcium ions on the interfacial behavior of beta-casein at the silicon oxide-aqueous solution interface. The structural characteristics of the adsorbed layer were determined from reflectivity curves fitted to three- and two-layer optical models. The results showed that the presence of divalent calcium ions decreased the specific electrostati

E3B1, a human homologue of the mouse gene product Abi-1, sensitizes activation of Rap1 in response to epidermal growth factor

E3B1, a human homologue of the mouse gene product Abi-1, has been implicated in growth-factor-mediated regulation of the small GTPases p21(Ras) and Rac. E3b1 is a regulator of Rac because it can form a complex with Sos-1 and eps8, and such a Sos-1-e3B1-eps8 complex serves as a guanine nucleotide exchange factor for Rac. In the present study, we found that overexpression of e3B1 in NIH3T3/ EGFR cel

Steam inretreatment of dilute H2SO4-impregnated wheat straw and SSF with low yeast and enzyme loadings for bioethanol production

Conversion of lignocellulosic material to monomeric sugars and finally ethanol must be performed at low cost, i.e, with limited consumption of chemicals, yeast and enzymes while still reaching high yields, if it is to compete with other fuel conversion processes. The objective of this study was thus to investigate ethanol production from steam-pretreated wheat straw by simultaneous saccharificatio

Distribution of different fibre types in human skeletal muscles. Fibre type arrangement in m. vastus lateralis from three groups of healthy men between 15 and 83 years

The effects of age on the fibre type arrangement in the human muscle m. vastus lateralis were studied. There were 10, 6 and 8 healthy men in the three age-groups with means 24, 52 and 77 years, respectively. For each fascicle considered, the numbers of type 1 (ST) and type 2 (FT) fibres on the boundary and internally, and the numbers of enclosed fibres of either type, were counted. The randomness

Experimental and numerical investigation of crack closure measurements with electrical potential drop technique

Crack closure measurements during fatigue crack propagation using the electrical potential drop (PD) technique is evaluated using a combination of experiments and simulations. From finite element simulations it is shown that variations in the potential drop value over a fatigue cycle can be explained by crack closure and strain induced conductivity changes. It is also demonstrated that closure mea

Estimating the relative nutrient uptake from different soil depths in Quercus robur, Fagus sylvatica and Picea abies

The distribution of fine roots and external ectomycorrhizal mycelium of three species of trees was determined down to a soil depth of 55 cm to estimate the relative nutrient uptake capacity of the trees from different soil layers. In addition, a root bioassay was performed to estimate the nutrient uptake capacity of Rb+ and NH4+ by these fine roots under standardized conditions in the laboratory.

Inhibition of inducible TNF-alpha expression by oxaspirodion, a novel spiro-compound from the ascomycete Chaetomium subspirale

In a search for compounds inhibiting the inducible TNF-alpha promoter activity in T cells, a new spirocompound, designated oxaspirodion, was isolated from fermentations of the ascomycete Chaetomium subspirale. Oxaspirodion inhibited TNF-alpha promoterdriven luciferase reporter gene expression with an IC50 value of 2.5 mug/ml (10 muM) in TPA/ionomycinstimulated Jurkat T cells. Studies on the mode o

Effects of cardioplegic flushing, storage, and reperfusion on coronary circulation in the pig

BACKGROUND: The aim of the study was to investigate how flush-perfusion of the heart with cold cardioplegic solution, 2 or 12 hours of cold ischemic storage, and 24 hours of reperfusion affect coronary endothelial function and coronary vascular resistance. METHODS: Porcine coronary arterial endothelial and smooth muscle function was studied in organ baths. An adult porcine working heart model was

Excess mortality in incident cases of diabetes mellitus aged 15 to 34 years at diagnosis: a population-based study (DISS) in Sweden

Aims/hypothesis: The objective of the study was to analyse the mortality, survival and cause of death patterns in incident cases of diabetes in the 15-34-year age group that were reported to the nationwide prospective Diabetes Incidence Study in Sweden (DISS). Methods: During the study period 1983-1999, 6,771 incident cases were reported. Identification of deaths was made by linking the records to

Human short-term repopulating cells have enhanced telomerase reverse transcriptase expression.

Telomerase activity has been suggested to be critically involved in hematopoietic stem cell (HSC) self-renewal. However, it has been unclear whether human HSCs have telomerase activity and how telomerase activity is regulated within the HSC and progenitor pool. Here, we isolated living cord-blood (CB) CD34+ cells with up-regulated human telomerase reverse transcriptase (hTERT) expression by using

Occupational risks for uveal melanoma results from a case-control study in nine European countries

Objective Uveal melanoma is a rare disease with poor prognosis and largely unknown etiology. We studied potential occupational risk factors. Methods A population based case-control study was undertaken during 1995-1997 in nine European countries using population and colon cancer controls with personal interviews. Occupational exposure to sunlight and artificial UV radiation was assessed with a job

Sensitivity of HIV-1 primary isolates to human anti-CD40 antibody-mediated suppression is related to co-receptor use

The effect of CD40 ligation on infection by HIV-1 primary isolates with different R5 phenotypes was evaluated with a novel set of anti-CD40 monoclonal antibodies originating from a human phage display library. Five human monoclonal anti-CD40 antibodies of IgG1 subtype characterized by the ability to activate B cells via CD40 were tested for induction of the CC-chemokines RANTES and MIP-1alpha and

A unique recent origin of the allotetraploid species Arabidopsis suecica: Evidence from nuclear DNA markers

A coalescent-based method was used to investigate the origins of the allotetraploid Arabidopsis suecica, using 52 nuclear microsatellite loci typed in eight individuals of A. suecica and 14 individuals of its maternal parent Arabidopsis thaliana, and four short fragments of genomic DNA sequenced in a sample of four individuals of A. suecica and in both its parental species A. thaliana and Arabidop

A nodal method for absorption-diffusion problems

We construct a nodal method for a two-dimensional absorption-diffusion problem. The method gives rise to a seven point stencil for which the truncation error analysis shows an accuracy of at least O(Δ2), where Δ is a uniform mesh parameter. We devise a numerical method which constructs a matrix whose entries are amplified according to contributions from each of the nodes in a rectangular domain. N

Assessing the potential of wind power in Romania within Kyoto targets

The Kyoto target for Romania was to reduce its carbon dioxide emissions by 8 % from the 1989 levels. The 1989 emissions were around 260 million tones. In 2000 the net CO2 emission - some 125 million tones - were 54% of the net CO2 emission in the reference year -1989, leaving some 115 million tones as a reserve or as a tradable resource to other countries that can not met their Kyoto targets. Assu