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Intumescent foams - A novel flame retardant system for flexible polyurethane foams

A combination of intumescent components was evaluated as a novel flame retardant system in a flexible polyurethane foam, and the incorporation of these components gave rise to a significant enhancement of the flame retardant properties of the foam. The heat release rate was lowered at an early stage as well as throughout the fire, the total heat production was decreased and the time to ignition wa

Modeling of Temperature Profiles in a Concrete Slab under Climatic Exposure

Effects of surrounding climate give temperature variations in both time and space for concrete structures. The associated thermal strains may give rise to stresses and cracking due to external or internal restraint. This will affect the performance of the structure. It is therefore important to analyze the temperature variations and the extreme situations that can occur. To predict the dynamic the

Bone-resorptive effects of endotoxin-contaminated high-density polyethylene particles spontaneously eliminated in vivo.

Wear particles commonly used for experiments may carry adherent endotoxin on their surfaces, which may be responsible for the observed effects. In this study, we attached titanium plates to the tibiae of 20 rats. After osseointegration, endotoxin-contaminated or uncontaminated high-density-polyethylene (HDPE) particles were applied. Contaminated specimens showed a dramatic resorption of bone after

Validation and clinical application of time-frequency analysis of atrial fibrillation electrocardiograms

Introduction: Fibrillatory rates can reliably be obtained from surface ECGs during atrial fibrillation (AF) and correspond with right atrial (RA) and coronary sinus (CS) rates, while both the relation with pulmonary venous (PV) rates and determinants of fibrillatory waveform are unknown. Class III antiarrhythmic drugs prolong atrial refractoriness and decrease its dispersion, effects that may be r

IR and EXAFS spectroscopic studies of glyphosate protonation and copper(II) complexes of glyphosate in aqueous solution

The varying degrees of protonation of N-(phosphonomethyl)glycine (PMG, glyphosate) were investigated with infrared JR) spectroscopy and ab initio frequency calculations. The zwitterionic nature of PMG in solution was confirmed, and intramolecular hydrogen bonding was identified. Successive protonation of the PMG molecule follows the order amine, phosphonate, carboxylate. Intramolecular hydrogen bo

Cyclin A1 expression and associations with disease characteristics in childhood acute lymphoblastic leukemia.

A critical cell cycle regulatory protein, cyclin A1, has been implicated in the development of acute myeloid leukemia (AML). Here, we have examined the expression and clinical significance of cyclin A1 in childhood acute lymphoblastic leukemia (ALL). Cyclin A1 was highly expressed in lymphoblastic leukemic cell lines and in 22 of 30 ALL patients (73%). Cyclin A1 expression correlated with patient

Micro processes of learning: exploring the interplay between conceptions, meanings and expressions

The article describes qualitative variation in micro processes of learning, focusing the dynamic interplay between conceptions, expressions and meanings of expressions in students' learning in higher education. The intentional-expressive approach employed is an alternative approach to the function of language use in learning processes. In the empirical investigation, a dialogue model was used that

Effects of liming on ectomycorrhizal fungi infecting Pinus sylvestris L. 2. Growth-rates in pure culture at different ph values compared to growth-rates in symbiosis with the host plant

Growth rates of ectomycorrhizal fungi were measured in pure culture at pH 3-8 on MMN-agar and sterilized peat, with and without nutrients added. Mycorrhizas were synthesized with Pinus sylvestris L. seedlings and the growth rate of the external mycelium was measured in peat at pH 3.8 and 7.3. The fungi were three isolates of Piloderma croceum Erikss. & Hjorts., two isolates of an unidentified

Radiation of extant marsupials after the K/T boundary: Evidence from complete mitochondrial genomes

The complete mitochondrial (mt) genomes of five marsupial species have been sequenced. The species represent all three South American orders (Didelphimorphia, Paucituberculata, and Microbiotheria). Phylogenetic analysis of this data set indicates that Didelphimorphia is a basal marsupial lineage followed by Paucituberculata. The South American microbiotherid Dromiciops gliroides (monito del monte)

Resistivity imaging in steep and weathered terrains

In areas where tectonics and weathering have hydrogeological significance, electrical methods can assist in mapping the subsurface. In this work, resistivity imaging was used to map fractures, faults and quartz veins emplaced in strongly weathered volcanic rocks. The aim was to map geological units related to the formation of groundwater systems in the Rio Artiguas basin, Nicaragua. Eight 2D resis

Preparation and properties of plasticized poly(lactic acid) films

Poly(lactic acid), PLA, was blended with monomeric and oligomeric plasticizers in order to enhance its flexibility and thereby overcome its inherent problem of brittleness. Differential scanning calorimetry, dynamic mechanical analysis, transmission electron microscopy, and tensile testing were used to investigate the properties of the blends. Monomeric plasticizers, such as tributyl citrate, TbC,

Expression and gene copy number analysis of ERBB2 oncogene in prostate cancer

An anti-ERBB2 antibody, trastuzumab, has been shown to be highly efficient in the treatment of metastatic breast cancers overexpressing the ERBB2 gene. It has been suggested that overexpression and even amplification of ERBB2 may play a role in the development of prostate cancer. Here, we have analyzed gene copy number and expression of the ERBB2 gene in both androgen-dependent primary and metasta

Increased CpG methylation of the estrogen receptor gene in BRCA1-linked estrogen receptor-negative breast cancers

A distinctive feature of BRCA1-linked breast cancers is that they typically do not express estrogen receptor-alpha (ERalpha). Previous investigation suggests that methylation of CpGs within the ERa promoter mediates repression of gene expression in some ERalpha-negative breast cancers. To determine if methylation of CpGs within the ERalpha promoter is associated with BRCA1-linked breast cancers, w

Added surfactant can change the phase behavior of aqueous polymer-particle mixtures

The phase behavior of aqueous mixtures of the "clouding" polymer ethyl(hydroxyethyl)cellulose (EHEC) mixed with colloidal particles and surfactants has been studied. These types of mixtures are important in many technical formulations. Two types of particles, polystyrene latex and silica, and two types of EHEC, nonmodified EHEC (N-EHEC) and hydrophobically modified EHEC (HM-EHEC), were studied. Th

Effect of vaginal delivery on endosonographic anal sphincter morphology

Objective To describe the effect of vaginal delivery with no clinically recognized sphincter tear on endosonographic anal sphincter morphology and sphincter pressure and to relate endosonographic results to anal sphincter pressure and anal incontinence score. Study design Thirty-two nullipara underwent anal endosonography and anal manometry in the third trimester of pregnancy, 2 weeks and 6 mon

Factors Controlling Phase Separation in Water-Salt Solutions of DNA and Polycations.

Factors affecting phase separation in water-salt solutions of polyelectrolyte complexes (PECs), formed by DNA and integral or pendant polycations with a quaternary amino group in every monomer unit, have been studied. When no salt was added, quantitative DNA precipitation occurred at a stoichiometric charge ratio, = [+]/[-] 1. In DNA mixtures with poly(N,N'-dimethyldiallylammonium chloride) (PDMDA

A novel diode laser system for photodynamic therapy

In this paper a novel diode laser system for photodynamic therapy is demonstrated. The system is based on linear spatial filtering and optical phase conjugate feedback from a photorefractive BaTiO3 crystal. The spatial coherence properties of the diode laser are significantly improved. The system provides an almost diffraction limited output which is efficiently coupled into a 50 mum core diameter