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Determination of isocyanates, aminoisocyanates and amines in air formed during the thermal degradation of polyurethane

An air sampling method for the determination of isocyanates. aminoisocyanates and amines formed during the thermal degradation Of polyurethane (PUR) is presented. The method is based on the collection of air samples using impinger flasks containing di-n-butylamine (DBA) in toluene with a glass fibre filter in series. Isocyanates are derivatized with DBA to urea derivatives, and amines are derivati

A combination of micro-porous membrane liquid–gas extraction and solid-phase trapping for ultra trace determination of benzene in urine

A method was developed for the determination of benzene in urine. The sample was pumped through the donor channel of a membrane extraction unit with a micro-porous membrane, separating the donor channel from an identical acceptor channel purged with nitrogen. The analyte reached the acceptor channel by diffusion through the membrane and was then swept by the carrier to a solid sorbent tube, where

Stenting of the biliary tract in children.

We report on the technique and results of percutaneous transhepatic biliary drainage (PTBD) in children with obstructive jaundice. Three patients aged 8 - 15 years were treated, two of them for a benign and one for a malignant stricture. Endoscopic treatment was not possible and all the PTBD procedures were done under general anaesthesia. One of the children was treated with external-internal drai

Tonogenetic mechanisms in Northern Mon-Khmer

In this paper, tonogenesis in the four languages Northern Kammu, Blang, Hu and U is analyzed. For comparison, register development in Lamet is treated as well. All these languages belong to the Palaungic and Kammuic branches of the Mon-Khmer division of the Austroasiatic language family and are fairly closely related, but they have developed tone or register systems independently of each other. Th

Species-specific song convergence in a moving hybrid zone between two passerines

Moving hybrid zones are receiving increasing attention. However, so far little is known about the proximate mechanisms underlying these movements. Signalling behaviour, by individuals engaged in interspecific sexual and aggressive interactions, may play a crucial role. In this study, we investigated song variation within a moving hybrid zone between two warblers, Hippolais polyglotta and H. icteri

Sorting for storage in myeloid cells of nonmyeloid proteins and chimeras with the propeptide of myeloperoxidase precursor.

During formation of polymorphonuclear neutrophils, proteins are synthesized for storage in granules. Whereas sorting of proteins into distinct subtypes of cytoplasmic granules may reflect the coordinated expression of the proteins contained in them, still the mechanism(s) for the retrieval of proteins from the constitutive secretion is unknown. To investigate the mechanisms of retrieval, nonmyeloi

Progress in the understanding of the protein C anticoagulant pathway.

A natural anticoagulant pathway denoted the protein C system provides specific and efficient control of blood coagulation. Protein C is the key component of the system and circulates in the blood as a zymogen to an anticoagulant serine protease.Activation of protein C is achieved on the surface of endothelial cells by thrombin bound to the membrane protein thrombomodulin. The endothelial protein C

Clinical and cytogenetic features of pediatric dic(9;20)(p13.2;q11.2)-positive B-Cell precursor acute lymphoblastic leukemias: A nordic series of 24 cases and review of the literature

Although dic(9;20)(p13.2;q11.2) is a characteristic abnormality in childhood B-cell precursor acute lymphoblastic leukemias (BCP ALL), little is known about its clinical impact or the type and frequency of additional aberrations it may occur together with. We here review the clinical and cytogenetic features of a Nordic pediatric series of 24 patients with dic(9;20)-positive BCP ALL diagnosed 1996

Alpha cell function in health and disease: influence of glucagon-like peptide-1

Although there is abundant evidence that hyperglucagonaemia plays a key role in the development of hyperglycaemia in type 2 diabetes, efforts to understand and correct this abnormality have been overshadowed by the emphasis on insulin secretion and action. However, recognition that the incretin hormone glucagon-like peptide-1 (GLP-1) exerts opposing effects on glucagon and insulin secretion has re

Novel flavonoids of Thelypteris torresiana

In our continuing research on cytotoxic components from the Formosan pteridophyte Thelypteris torresiana (GAUD.) ALSTONONE, two new compounds, a novel flavonoid, flavotorresin (1), and a flavonoid diglycoside, multi-florin C (2), along with five known compounds, were isolated. The structural elucidation was established on the basis of spectroscopic data analysis. The possible biosynthetic pathway

Numerical and experimental evaluation of springback in a front side member

In this study, a part of an automotive side front section (front side member inner) was studied and a comparison both regarding material behaviour and of accuracy of the FE simulations was made. Mild steel, Rephos steel and TRIP700 were compared both experimentally and numerically. The results showed that TRIP steel has a significantly larger springback than the other materials. Furthermore, the F

Exact and asymptotic dispersion relations for homogenization of stratified media with two phases

Using exact dispersion relations for electromagnetic wave propagation in layered, periodic media, consisting of two phases, we derive explicit asymptotic solutions for small wavenumbers. These solutions are compared to the numerical solutions of the exact dispersion relations, and applications to homogenization problems are discussed. The results can be used as test cases for homogenization techni

Leadership and implementation of evidence-based practices

Purpose – This paper seeks to investigate the role of leadership styles in the implementation of evidence-based treatment methods (EBP) for drug abuse and criminal behaviour. Design/methodology/approach – The paper employs a triangulation approach through mail questionnaires to 112 treatment personnel (49 per cent response rate), interviews with 65 employees and managers, observations and feedbac

Aqueous phase behavior and dispersed nanoparticles of diglycerol monooleate/glycerol dioleate mixtures

The first part of this study concerns the aqueous phase behavior of mixtures of diglycerol monooleate (DGMO) and glycerol dioleate (GDO) examined by X-ray diffraction (XRD). The ternary phase diagram displays a multitude of liquid crystalline phases (polymorphism). With increasing GDO content the following phase sequence was observed: lamellar (L-alpha); two reversed bicontinuous cubic phases (Q(2

Effect of high water-holding capacity on the formation of heterocyclic amines in fried beefburgers.

Mutagenic/carcinogenic heterocyclic amines (HAs) are formed in the crust during the cooking of meat. The influence of cooking loss, time, and temperature on the formation of HAs was investigated in fried beefburgers. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) were

Reducing NOx in diesel exhausts by SCR technique: Experiments and simulations

Results of experiments are compared to simulations of the performance of V2O5/gamma-alumina SCR catalyst used to remove nitrogen oxides from diesel exhausts. The kinetic model is based on Eley-Rideal kinetics. Temperature programmed desorption (TPD) of the ammonia is used to evaluate adsorption/desorption parameters. Stationary experiments on a 3.6-dm(3) engine with a 4.8-dm(3) honeycomb catalyst

Expression of the Aspergillus aculeatus Endo- beta-1,4-mannanase Encoding Gene ( man1 ) in Saccharomyces cerevisiae and Characterization of the Recombinant Enzyme

The endo-beta-1,4-mannanase encoding gene man1 of Aspergillus aculeatus MRC11624 was amplified from mRNA by polymerase chain reaction using sequence-specific primers designed from the published sequence of man1 from A. aculeatus KSM510. The amplified fragment was cloned and expressed in Saccharomyces cerevisiae under the gene regulation of the alcohol dehydrogenase ( ADH2PT ) and phosphoglycerate