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Combustion products generated by hetero-organic fuels on four different fire test scales

The scaling of results from combustion experiments with four organic substances containing heteroatoms, carried out on four different scales, is discussed. The scales ranged from the micro-scale, using about 2 x 10(-3) kg of the substances, to large scale using about 50 kg of the substances. The content of O-2, CO, CO2, NOx, HCl, HCN and SO2 in the combustion gases were determined with special att

Interaction of metals and thiols in cell damage and glutathione distribution: potentiation of mercury toxicity by dithiothreitol

In the present study, we have investigated the effects of extracellular redox status and metal/thiol interactions on glutathione distribution in HeLa cell cultures. No effects were seen on glutathione distribution after the addition of different thiols, whereas the pro-oxidant copper ions affected glutathione distribution in several ways. The addition of dithiothreitol (DTT) but not the other thio

Phenotypic modulation of cultured bladder smooth muscle cells and the expression of inducible nitric oxide synthase.

Phenotypic modulation of smooth muscle is associated with various pathological conditions, including bladder dysfunction. Cytoskeletal dynamics modulate the cell phenotype and were recently shown to be involved in regulation of inducible nitric oxide synthase ( iNOS). We tested the hypothesis that the cell differentiation status affects iNOS expression, and that iNOS is preferentially expressed in

Luminescence control in the marine bacterium Vibrio fischeri: An analysis of the dynamics of lux regulation

A mathematical model has been developed based on the fundamental properties of the control system formed by the lux genes and their products in Vibrio fischeri. The model Clearly demonstrates how the components of this system work together to create two, stable metabolic states corresponding to the expression of the luminescent and non-luminescent phenotypes. It is demonstrated how the cell can "s

Monte Carlo simulation of defect-free cross-linked polyelectrolyte gels

Model systems of cross-linked polyelectrolyte gels were investigated by means of Monte Carlo simulations. The model contained a charged defect-free th ee-dimensional network of a diamond-like topology and explicit counterions. Pressure vs volume relations and chain extensions were determined and compared to those of the corresponding polyelectrolyte solution. The structure of the gel was character

Binding of SDS to Ethyl(hydroxyethyl)cellulose. Effect of Hydrophobic Modification of the Polymer

The binding of SDS to cellulose polymers in the semidilute concentration regime has been studied by means of NMR, ion-selective electrode, and a time-resolved fluorescence technique. Two polymers have been used, differing only in a low degree of hydrophobic modification of one of them. NMR self-diffusion and activity measurements show that the binding of SDS to the nonmodified polymer has a fairly

The methylmercury cycle in Little Rock Lake during experimental acidification and recovery

The cycle of waterborne methylmercury (meHg) in Little Rock Lake is characterized by a period of accumulation during summertime (when the lake is warm and open to the atmosphere) and a period of decline during winter (when the lake is scaled by ice). We followed this cycle for 16 yr. during which time the lake was acidified with H,SO., and then allowed to recover naturally as part of a long-term f

Interrelationship Between Lule City Lakes

The influence of the Bay of Bothnia sea level on the water stages in a series of interconnected lakes near the city of Lulea in Sweden is studied. Future conditions as a consequence of land elevation and channel improvements are simulated using a mathematical model. It is found that due to landlift the lake system will be divided into two lake systems. The upper lakes will turn to true lakes exper

Jitterbug: A Tool for Analysis of Real-Time Control Performance

The paper presents Jitterbug, a Matlab-basedtoolbox for real-time control performance analysis. The controlsystem is described using a number of connected continuous-time anddiscrete-time linear systems. The control performance is measured bya continuous-time quadratic cost function. A stochastic executionmodel is used to describe when the different discrete-time systemsare updated during the cont

p38-MAPK Signals Survival by Phosphorylation of Caspase-8 and Caspase-3 in Human Neutrophils.

Neutrophil apoptosis occurs both in the bloodstream and in the tissue and is considered essential for the resolution of an inflammatory process. Here, we show that p38–mitogen-activated protein kinase (MAPK) associates to caspase-8 and caspase-3 during neutrophil apoptosis and that p38-MAPK activity, previously shown to be a survival signal in these primary cells, correlates with the levels of cas

Structure study of Bi2.5Na0.5Ta2O9 and B2.5Nam-1.5NbmO3m+3 (m=2-4) by neutron powder diffraction and electron microscopy

The crystal structures of Bi2.5Na0.5Ta2O9 and Bi2.5Nam-1.5NbmO3m+3 (m = 3,4) have been investigated.ysis of their neutron powder diffraction by the Rietveld anal patterns (lambda = 1.470 Angstrom). These compounds belong to the Aurivillius phase family and are built up by (Bi2O2)(2+) fluorite layers and (A(m-1)BnO(3m+1))(2-) (m = 2-4) pseudo-perovskite slabs. Bi2.5Na0.5Ta2O9 (m = 2) and Bi2.5Na2.5

Synthesis of boronate-contaming copolymers of N,N-dimethylacrylamide, their interaction with poly(vinyl alcohol) and rheological behaviour of the gels

Cross-linking of polyvinylalcohol (PVA) by boronate-containing copolymer of N,N-dimethylacrylamide (DMAA, 1) was studied and compared to cross-linking of PVA by borate buffers in weakly alkaline solutions. The copolymer of M-w = 19,000 g mor(-1) containing 9 mol% N-acryloyl-m-aminophenylboronic acid (NAAPBA, 2) was prepared by free radical polymerization of the monomers, exhibiting copolymerizatio

Loss of C/EBP alpha cell cycle control increases myeloid progenitor proliferation and transforms the neutrophil granulocyte lineage

CCAAT/enhancer binding protein (C/EBP)alpha is a myeloid-specific transcription factor that couples lineage commitment to terminal differentiation and cell cycle arrest, and is found mutated in 9% of patients who have acute myeloid leukemia (AML). We previously showed that mutations which dissociate the ability of C/EBP alpha to block cell cycle progression through E2F inhibition from its function

The shortened disabilities of the arm, shoulder and hand questionnaire (QuickDASH): validity and reliability based on responses within the full-length DASH

BACKGROUND: The 30-item disabilities of the arm, shoulder and hand (DASH) questionnaire is increasingly used in clinical research involving upper extremity musculoskeletal disorders. From the original DASH a shorter version, the 11-item QuickDASH, has been developed. Little is known about the discriminant ability of score changes for the QuickDASH compared to the DASH. The aim of this study was to