bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of renovascular hypertension on myocardial protein patterns: Analysis by computer‐assisted two‐dimensional gel electrophoresis
Authors: Pleißner Klaus‐Peter , Regitz‐Zagrosek Vera , Krüdewagen Bernd , Trenkner Jörg , Hocher Berthold , Fleck Eckart
Published: May 2005

Hypertensive heart disease caused by renovascular hypertension reflects the response of the heart to an increased afterload and neurohormonal stimulation. We hypothesized that in this condition the composition of the myocardial proteins of rats was altered. To identify yet unknown quantitative and qualitative differences in myocardial proteins in renovascular hypertensive heart disease, we analyzed protein patterns by computer‐assisted two‐dimensional polyacrylamide large gel electrophoresis. Renovascular hypertension was induced by placing a silver clip on the left renal artery in 9‐week‐old rat siblings. Sham‐operated animals served as controls. Systolic blood pressure (197 ± 19 mm Hg) and heart/body weight ratios (0.36 ± 0.04%) were significantly increased in the hypertensive animals. Twenty protein patterns from the left ventricle of five hypertensive and five control rats were compared. The molecular mass and isoelectric point (pI) of proteins spots ranging from 13 to 100 kDa and from 4.5 to 8.5, respectively, were determined using marker proteins. In total, 761 ± 88 protein spots were resolved in all twenty gels. For the quantitative data analysis a univariate (Mann‐Whitney test) as well as a multi‐variate statistical approach (correspondence analysis) were applied. Only one myocardial protein spot (molecular mass = 41.3 kDa; pI = 6.3) was decreased by more than twofold (p < 0.05) in renovascular hypertension. The vast majority of spots did not indicate a significant alteration of intensity. Left ventricular hypertrophy in early renovascular hypertension induces a form of myocardial hypertrophy that conserves the naturally occurring protein expression pattern.
Size separation of sodium dodecyl sulfate complexes of human plasma proteins by capillary electrophoresis employing linear polyacrylamide as a sieving polymer
Authors: Manabe Takashi , Oota Hideto , Mukai Jun
Published: May 2005

Electrophoretic conditions to separate sodium dodecyl sulfate (SDS) complexes of human plasma proteins according to their size differences, by capillary electrophoresis employing linear polyacrylamide as a sieving matrix (LPA‐CE), have been examined. Using the optimized separation conditions, SDS complexes of human plasma proteins not treated with reducing agents were separated into about 40 peaks and shoulders within 60 min. The molecular mass values of major peaks in a separation pattern were estimated from a plot of molecular mass and migration time for standard proteins and some of the major plasma proteins have been identified on the pattern. The electrophoretic conditions were successfully applied for the analysis of proteins in immunoglo‐bulin G (IgG) myeloma sera.
Application of capillary electrophoresis, liquid chromatography, electrospray‐mass spectrometry and matrix‐assisted laser desorption/ionization ‐ time of flight ‐ mass spectrometry to the characterization of recombinant human erythropoietin
Authors: Zhou Guo‐Hua , Luo Guo‐An , Huang Le‐Qun , Zhou Yong , Zhang Xiao‐Dano , Zhou Ke‐Yu
Published: May 2005

High performance capillary electrophoresis (HPCE), high performance liquid chromatography (HPLC), matrix‐assisted laser desorption/ionization ‐ time of flight ‐ mass spectrometry (MALDI‐TOF‐MS), on‐line CE‐electrospray ionization‐mass spectrometry (CE‐ESI‐MS) and on‐line LC‐ESI‐MS have been employed to characterize a heterogeneous glycoprotein, recombinant human erythropoietin (rHuEPO) expressed from Chinese hamster ovary (CHO) cells. The analysis was demonstrated through two specific levels of detail: the intact protein and tryptic digests of the protein. Six glycoforms of rHuEPO were separated by HPCE; seventeen tryptic fragments in a total of 21 nonglycosylated and glycosylated peptides were characterized; the O‐linked glycopeptides were analyzed directly by CE‐ESI‐MS and LC‐ESI‐MS. In particular, four glycans of O‐acetylation of sialic acid were identified in the O‐linked glycosylated fragments. The molecular weight of rHuEPO was accurately determined by MALDI‐TOF‐MS.
Multiplex polymerase chain reaction of Alu polymorphic insertions
Authors: Thomas Emmanuel , Herrera Rene J.
Published: May 2005

Alu sequences are present in humans in excess of 500 000 copies per haploid genome and represent the largest family of short interspersed repetitive elements (SINEs). These mobile genetic elements are ancestrally derived from the 7SL RNA gene and move throughout the genomes of primates by retroposition. Polymorphic Alu insertions have proven to be useful for population studies, paternity determinations and forensic applications. Additionally, a simple polymerase chain reaction (PCR)‐based assay has been established to examine these polymorphisms. In the present study, we have applied the technique of multiplex polymerase chain reaction to the Alu polymorphic system. Duplex and triplex PCR reactions were performed for the analysis of five different Alu polymorphic loci in different combinations. This study represents a starting point for further experimentation to improve and eventually optimize Alu multiplex PCR.
Triple helix‐forming oligonucleotides which make imperfect Watson‐Crick duplexes that compete with the creation of the triplex
Authors: Porumb Horea , Gousset Hervé , Taillandier Eliane
Published: May 2005

Because of the repetitive nature of the sequence, when titrating a G,A‐rich, triple helix‐forming oligonucleotide (TFO) with increasing concentrations of target duplex in order to obtain the dissociation constant of the complex, a duplex is sometimes first generated at intermediate concentrations of the target. This duplex is based on an imperfect Watson‐Crick pairing of the TFO to the pyrimidine‐rich strand of the target. An explanation is proposed for this duplex being obtained only in a certain domain of the titration range, before the triple helix becomes predominant.
Development and comparison of assays for measuring immunospecific antibody response in serum of chickens and rabbits immunized with human immunoglobulin G
Authors: Bollen Lise S. , Hau Jann
Published: May 2005

The antibody response development during polyclonal antibody production is a relevant parameter to monitor during the immunization period to be able to optimize the immunization protocol and to determine the optimal antibody harvest time. Although rabbits and other mammals are most often used for polyclonal antibody production, the chicken is a relevant alternative. There are both scientific reasons, economic reasons, and animal welfare reasons to consider when choosing the chicken instead of a mammal for this purpose, because antibodies in generous quantities can be harvested from the egg yolk. This study compared different assays for measuring antibody response in rabbit and chicken serum. An inhibition liquid phase absorption assay (ILPAA), a rocket immunoelectrophoresis (RIE) assay, and a line immunoelectrophoresis (LIE) assay were compared to ELISAs. The ELISA proved to be the most useful assay for routine use, as it was less time‐consuming and because the assay could easily be adapted to both serum antibody types. However, electrophoretic assays were the most useful as combined analytical and quantitative tools and must be considered essential when analyzing specificities of polyclonal antibody preparations.
Boundary element modeling of electrokinetically driven fluid flow in two‐dimensional microchannels
Authors: Hoyt Jeffrey J. , Wolfer Wilhelm G.
Published: May 2005

In recent years there has been considerable intrerest in fabricating electrophoretic separation systems on microchips. In this study the boundary element method is used to numerically model both the electrical charge density and the electrokinetically driven fluid flow velocity field in two‐dimensional micro‐channels containing an arbitrary configuration of circular flow obstacles. An estimate of both the average velocity and the resolution has been determined for various obstacle configurations, obstacle sizes, area fractions, surface line lengths per unit area and for different values of the thickness of the electrical double layer. Based on the results, an optimal microchannel design is suggested. In addition, the recently observed phenomenon of recirculated flow in an open region of an otherwise packed electrochromatography column has been confirmed with the numerical model.
Use of ethanolamine for sample stacking in capillary electrophoresis
Authors: Louwagie Mathilde , Rabilloud Thierry , Garin Jérǒme
Published: May 2005

Capillary zone electrophoresis (CZE) in the presence of ethanolamine was used in a micropreparative mode. Sample volumes up to 1 μL could be loaded onto a 100 μm diameter capillary without loss in resolution. Coupled to narrow‐bore reversed‐phase high‐performance liquid chromatography, ethanolamine‐CZE allowed the collection of sufficient amounts of pure peptidic material to perform amino acid sequence analysis.
High speed separation of DNA fragments by capillary electrophoresis in poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) triblock polymer
Authors: Liang Dehai , Chu Benjamin
Published: May 2005

The high speed separation of DNA fragments by using a triblock copolymer, 25% w/v F127 (PEO99PPO69PEO99 with PEO and PPO denoting polyethylene oxide and polypropylene oxide, respectively) which is easy to handle and does not need coating of the quartz capillary, has been investigated. Two ways to decrease the run time are presented: one is to shorten the effective capillary length and the other to increase the electric field strength. In a short capillary, the sieving ability of the separation medium versus the initial band width, and the band width spreading as a function of distance traveled dominate the resolution; at high electric field strength, Joule heating could deteriorate the separation. By taking both effects into account, the ΦX174/HaeIII digest could be separated within 100s by using an 8 mm effective length, 50 μm diameter capillary operating at 300 V/cm.
Preparative capillary zone electrophoresis in combination with off‐line graphite furnace atomic absorption for the analysis of DNA complexes formed by a new aminocoumarine platinum (II) compound
Authors: Deforce Dieter L. D. , De Leenheer Andreas , Van Den Eeckhout Elfriede G. , Kokotos George , Esmans Eddy L.
Published: May 2005

Calf thymus DNA was incubated in vitro with a new aminocoumarin platinum(II) complex in order to study its interaction with DNA. The platinated DNA was hydrolyzed enzymatically to the 5′‐mononucleotide level using DNAase I and nuclease P1. Analysis of the DNA hydrolysate with capillary zone electrophoresis (CZE), using sample stacking, revealed the presence of unhydrolyzed oligonucleotides in the platinated DNA. A homemade system, using only some plastic pipet tips, was constructed to collect the oligonucleotide fraction during CZE analysis. The platinum content of this fraction was determined using graphite furnace atomic absorption with Zeeman background correction. This system proved to be a useful tool to detect platinated DNA species (with a quantifiable detection limit for the detection of platinum of 0.78 ng). Subsequent gel filtration experiments confirmed the presence of high molecular weight oligonucleotides that were platinated. This was proven by reversal of the platination using thiourea and subsequent enzymatic hydrolysis to 5′‐mononucleotides.
Particle electrophoresis of micrometric‐sized superparamagnetic particles designed for magnetic purification of cells
Authors: Sestier Claude , Sabolovic Domagoj
Published: May 2005

Measuring the electrophoretic mobility of superparamagnetic particles (0.5–4.5 μm mean size) was undertaken to probe the coupling of lectins and antibodies to their surface. Coupling was either noncovalent (antigen‐antibody and biotinstreptavidin linkage) or covalent (tosyl‐activated beads). The direct observation of the electrophoresis of single particles illuminated in dark field and processed by image analysis allowed the determination of their apparent electrophoretic mobility. Mobilities ranged from −0.5 μm s−1/CmV−1 to + 1 μm s−1/CmV−1 when measured at 20°C in 0.15 M NaCl and 30 mg/mL sorbitol, pH 7.4. The relative standard deviation was less than 0.1%. Surface immobilization of charged proteins onto the superparamagnetic beads shifted their electrophoretic mobility up to 200%; this was also quantitatively correlated with some specific properties (enzymatic activity, antigen‐binding activity, lectin‐binding activity). Although particle electrophoresis has mainly been reported for the study of surface adsorption phenomenon, it may be a versatile tool for controlling covalent modifications of particles designed for therapeutical targeting or chromatographic use and may also apply to a quantitative analysis of ligand‐binding interactions.
Determination of glucose by capillary electrophoresis/laser‐induced fluorescence in transdermally collected samples
Authors: Frerichs Valerie , Colón Luis A.
Published: May 2005

Capillary electrophoresis (CE) with laser‐induced fluorescence (LIF) detection has been used for the determination of glucose in samples collected by noninvasive means. The method uses an enzymatic reaction scheme that provides for the determination of small quantities of glucose with detection limits of 80 nM. This approach is used to evaluate passive transdermal diffusion as a noninvasive means to sample glucose in vivo. A simple sampling cell design is presented. Sample collection was performed on volunteer human subjects. Our experiments show that fluctuations in blood glucose concentration are reflected in the samples obtained by passive transdermal diffusion after glucose intake. The results indicate that glucose from the subcutaneous fluid can be accessed by passive diffusion.
Peptide capillary zone electrophoresis mass spectrometry of recombinant human erythropoietin: An evaluation of the analytical method
Authors: Boss Hollis J. , Watson Daniel B. , Rush Robert S.
Published: May 2005

An evaluation of capillary zone electrophoresis‐mass spectrometry (CZE‐MS) as an analytical methodology for the separation and characterization of complex glycopeptides and nonglycopeptide structures has been performed. The evaluation employed endoproteinase V8 digested recombinant human erythropoietin (rHuEPO) that was further fractionated by reverse phase chromatography. The peptides were subjected to sequence analysis and evaluated by capillary electrophoresis, with or without mass detection, for peptide purity. The peptide mass determined from the sequence was then compared to the mass obtained from CZE‐MS. Glycosylation sites and carbohydrate branch patterns were easily determined, site specific microheterogeneity (either O‐acetylation of N‐acetylneur‐aminic acids or lactosamine extensions of the carbohydrate chain length) was assessed directly, glycosylation site occupancy was evaluated qualitatively, and nonglycopeptides were resolved and analyzed on‐line with ease. Incomplete peptide digestion products were detected and identified by CZE‐MS. Protein sequence coverage by CZE‐MS was 98.2 percent complete from a single map. Offline evaluation of peptide purity by CZE greatly aided the interpretation of multiple sequence analysis and, in validating that, the CZE‐MS was detecting all peptides present. All off‐line CZE and on‐line CZE‐MS experiments employed a capillary that was dynamically coated with Polybrene in the presence of polyethylene glycol; separations were conducted in 0.67 M formic acid.
Characteristics of selective polymerase chain reaction (PCR) using two‐base anchored primers and improvement of its specificity
Authors: Okano Kazunori , Uematsu Chihiro , Matsunaga Hiroko , Kambara Hideki
Published: May 2005

We have developed a reliable method for eliminating base‐mispair amplification in selective polymerase chain reaction (PCR), which is utilized for amplifying unknown sequence fragments produced by restriction enzyme reaction. The proposed procedure applies amplified fragment length polymorphism (AFLP) with high fidelity. Selective PCR utilizes the known polymerase reaction characteristic that the complementary strand extension is strongly affected by matching a template with the 3′‐terminus of the primers. However, false positive amplification is frequently observed because the specificity of terminal bases for discrimination of fragments (usually, 1–3 anchor sequences) is not enough to separate each fragment. A protocol for the selective PCR separation of every fragment was therefore investigated. A single‐base mismatch was artificially introduced on the 4th base position from the 3′ end of the primers to improve the hybridization specificity of anchored 2‐bases at the 3′ termini of primers. PCR reaction was carried out at 66°C to prevent false positive amplification. The concentration of the primers having anchored‐base sequences of AA, AT, TA, and TT must be three times larger than that of other primers because the Tm values for these sequences are lower than the others. As all the fragments can be separated into groups with high fidelity, the improved selective PCR will be applied to gene finding and analyzing differences on genome sequences based on AFLP.
Minisatellite variant repeat (MVR) analysis of the HRAS1 minisatellite locus
Authors: Vega Ana , Barros Francisco , Bellas Susana , Carracedo Angel
Published: May 2005

Two alternative electrophoretic strategies were used to study the internal variation of the HRAS1 minisatellite after minisatellite variant repeat mapping (MVR‐PCR) was carried out. While the use of automated sequencers with fluorescent based technology is ideal for analyzing fragment size, and therefore, for analyzing the repeat number, the use of polyacrylamide gels and silver staining is more appropriate for the analysis of internal variation. Thirteen different fragments ranging from 27 to 80 repeats were found in a sample from 80 healthy Caucasian individuals. By using MVR mapping we were able to detect heterozygotes which appear as homozygotes when fragment length analysis was used. As a result of this, the 13 alleles, which we had detected, increased to 16 alleles when MVR sequences were analyzed. The extremely conservative arrays of repeats allow us to infer the theoretical origin of rare alleles from a major group of specific alleles. The HRAS1 minisatellite has been extensively studied due to its association with cancer. However, the methodology used up to now has limited the scope of previous research. Our approach permits the identification of alleles in a fast and reliable way using their MVR codes, thus allowing association studies with cancer.
Stability of continuous flow electrophoresis
Authors: Weber Gerhard , Boček Petr
Published: May 2005

The stability of continuous flow electrophoresis (CFE) was tested by performing uninterrupted continuous flow cationic isotachophoresis for 15 h, using a mixture of two synthetic isoelectric point (pI) markers as the model sample. This sample as well as the other operational electrolytes were continuously pumped into the CFE separation chamber via 10 individual inlets. The operational electrolyte system and the arrangement of the electrolyte streams were selected in accord with previously published results, providing a stable electrophoretic regime. The chamber had 96 individual outlets and here 96 individual fractions were collected in microwell plates in regular time intervals and scanned photometrically. The scanned photometric patterns proved that CFE is sufficiently stable for an overnight operation.
Finding a universal low viscosity polymer for DNA separation (II)
Authors: Heller Christoph
Published: May 2005

When investigating the use of different polymers for capillary electrophoresis we found that poly‐N,N‐dimethylacrylamide (pDMA) has a very low viscosity compared to other polymers of comparable molecular mass and resolving power. This makes it a potentially useful matrix for DNA separation in multi‐capillary electrophoresis, where short cycle times or low pressure for matrix replacement are preferred. We have characterized this matrix by systematic studies on concentration, chain length and field strength dependence. It is shown that pDMA performs well for the separation of oligonucleotides and double‐stranded DNA fragments. Together with the application of DNA sequencing, pDMA is a universal polymer for the separation of biological macromolecules.
A theory for the electrophoretic separation of DNA in polymer solutions
Authors: Sunada Wade M. , Blanch Harvey W.
Published: May 2005

We present a mathematical model of DNA capillary electrophoresis in polymer solutions based on nonentangling collisions between DNA and polymer molecules. Using videomicroscopy images of DNA migrating through polymer solutions, we propose a modified transient entanglement coupling mechanism for DNA separations that includes nonentangling DNA/polymer collisions. We show that a mathematical model based on individual nonentangling DNA/polymer collisions is able to predict the mobilities of DNA in solutions of low molecular mass polymer. We compare the model predictions to mobility data for separations of DNA in a range of concentrations for solutions of both hydroxypropylcellulose (Mw 100 000) and hydroxyethylcellulose (Mw 139 000). The model relies on one fitted parameter, the time constant for the interaction between the DNA and polymer molecules, which is based on the physical properties of DNA and polymers.
High‐frequency alternating‐crossed‐field gel electrophoresis with neutral or slightly charged interpenetrating networks to improve DNA separation
Authors: Boyd Brooks M. , Prausnitz John M. , Blanch Harvey W.
Published: May 2005

Toward improving DNA separations, this work reports the effects of high‐frequency square‐wave AC fields superimposed perpendicular to the direct current (DC) separation field on DNA migration in both polyacrylamide‐based interpenetrating networks (IPNs) and in agarose networks. Compared to standard polyacrylamide gels, IPNs allow the separation of larger DNA (9000 bp vs. 5000 bp at 5 V/cm). In novel polyacrylamide‐based IPNs, an alternating current (AC) field of 5 Hz increased the maximum DNA size separable. This effect was extended to larger DNA sizes with increasing electric‐field strength up to and apparently beyond the power supply‐limited maximum electric‐field strength of 48 V/cm. The orthogonal AC field also increased mobility. These two results combine to yield a reduction in separation time of up to a factor of 20 in novel polyacrylamide‐based IPNs. When negatively charged acrylic‐acid groups were incorporated into the IPNs, the use of the AC field changed the DNA‐network interaction, which altered the size dependence of DNA mobility. In agarose gels, an AC field of 50 Hz increased the size range separable; however, there was no increase in DNA mobility. There was no change in size dependence of mobility in an AC field when the number of charged groups in the agarose network was increased. Based on results in the literature, possible mechanisms were examined for the effects of the AC field on DNA separation.
Two‐dimensional electrophoretic analysis of membranous protein from human thyroid tissues and cancer cell lines
Authors: Lin Jen‐Der , Chan Err‐Cheng , Weng Hsiao‐Fen , Sheu Cherng‐An
Published: May 2005

Thyroid neoplasm is the most commonly encountered neoplastic disorder in endocrine clinics. Thyroid scan, ultrasonography, and fine needle aspiration cytology (FNAC) are used as diagnostic tools to differentiate a malignant nodule from a benign lesion. There are certain limitations and pitfalls in FNAC, especially in the diagnosing of follicular tumors. The lack of characteristic findings or a specific tumor marker are the most common problems in the preoperative diagnosis of thyroid follicular carcinoma. Although serum thyroglobulin level has been used as a tumor marker for post‐operative, well‐differentiated thyroid cancer, the assay cannot be used for preoperative diagnosis of thyroid carcinoma. In this study, various thyroid tissues and cancer cell lines including CGTH W‐1, CGTH W‐3, RO 82 W‐1, SW 579 cell lines were used for the investigation of tumor markers. Specific spots were identified in the area near the 60 kDa molecular mass protein and isoelectric point (pI) 5.9 of the CGTH W‐1 cell line. These spots could not be found in the papillary or anaplastic thyroid cancer cell lines. Another spot with a molecular weight of about 9.8 kDa with a low pI of 4.8 was present in the CGTH W‐1 and RO 82 W‐1 cell lines. This spot appeared to be a tumor marker of follicular cancer cells. This spot could not be found in the papillary and anaplastic cancer cell lines and other benign thyroid tissues. Specific proteins that were identified in this study may be useful as tumor markers for follicular thyroid carcinoma.
Studies of the smoke emission from burning poly‐(vinylchloride) plasticized with diisooctylphthalate
Authors: Delfosse L. , Špilda I. , Pavlik J.
Published: May 2005

Smoke evolved from burning poly‐(vinychloride) plasticized with diisooctylphthalate has been studied using a light absorption method. It has been shown that the quantity of smoke produced depends upon the oxygen concentration of the oxidizing gas as well as on the concentration of diisooctylphthalate present in the polymer. The results of this work have been analysed using an empirical equation proposed by the authors, which correlates the maximum smoke density (σmax) with oxygen concentration. This equation may be written

where No2 is the molar concentration of oxygen in the oxidizing gas, and LOI refers to the limiting or critical concentration of oxygen at which at the polymer will just burn, as defined by the ASTM test 2863. The effect of various additives, particularly organic iodine compounds, as smoke suppressants has also been investigated.
Moving wire technique studies of ablation, ignition and extinction of polymer flames
Authors: Fristrom R. M. , Grunfelder C.
Published: May 2005

A new experimental method for studying the ablation, ignition and extinction of polymers exposed to flames and other ignition sources is presented. The technique is called the ‘Moving Wire Technique’. The polymer sample is carried on a wire support which is moved uniformity through the ignition source which is a flame in the example given. In the laboratory coordinate system, points along the path of the wire correspond to increasing residence time. The polymer combustion thus becomes a steady‐state phenomena which can be studied at leisure with the improvements in precision associated with long time steady‐state measurements. In addition to steady‐state combustion, ignition and extinction transitions are observed whose onsets are sharp and can be accurately characterized in this system. In a favorable case, a reproducibility of a few parts per thousand is attained in determining critical ignition exposure times and extinction velocities. Results from initial studies of commercial Teflon® and poly‐(vinylchloride) are presented. Measurements include critical ignition times and extinction velocities a function of free oxygen concentration. For poly‐(vinylchloride), measurements are given of gas phase composition, mass loss of the polymer, and surface temperature of the polymer as a function of exposure time. A discussion is given of the relation of the results to other experiments and potential uses of the technique.
A comparison of flashover times in small‐scale fires using test data
Authors: Bullen M. L.
Published: May 2005

Reaction to fire standard tests on materials used as linings are not sufficient in themselves to predict the behaviour of growing fires. However, flashover times with cellulosic linings have been correlated qualitatively with the British test, but generally there is wide divergence in the test results from different countries. This report paper discusses some aspects of this problem.
Sensory irritation evoked by the thermal decomposition products of plasticized poly(vinyl chloride)
Authors: Barrow Craig S. , Alari Yves , Stock Maryanne F.
Published: May 2005

A decrease in respiratory rate in mice during exposure to irritating airborne chemicals has been utilized as a response parameter to characterize the degree of upper respiratory tract irritation (sensory irritation) to the thermal decomposition products of plasticized poly(vinyl chloride). The plasticized poly(vinyl chloride) was placed in a low mass vertical furnace and thermally decomposed in an air atmosphere at a programmed heating rate of 20°C min−1. The thermogravimetric study of the plasticized poly(vinyl chloride) demonstrated that two distinct weight loss fractions occurred during the decomposition process. Groups of four male swiss‐webster mice were exposed to the thermal decomposition products of the first weight loss fraction in the range 0.03–0.77 mg l−1 and to the second weight loss fraction in the range 0.03–0.38 mg l−1. Dose‐response curves were plotted by utilizing the maximum percent decrease in respiratory rate during each exposure as the response parameter. Comparison of these curves to a dose‐response curve for hydrogen chloride showed that both the first and second weight loss fraction of plasticized poly(vinyl chloride) were more potent than hydrogen chloride in terms of sensory irritation. From these dose‐response relationships qualitative and quantitative predictions of human responses to the thermal decomposition products of plasticized.
Effect of the nature of fuel on the characteristics of fully developed compartment fires
Authors: Harmathy T. Z.
Published: May 2005

The coupling between the constituent reactions of a burning process, namely pyrolysis, combustion of volatiles, and (possibly) oxidation of char, is on the whole quite different for fires occurring in the open and for those that develop in an enclosure. Consequently, knowledge of the characteristics of free burning fires is of only limited value in studies related to compartment fire. Since the singe‐rout communication between the fire compartment and its environment, always assumed in classical fire studies, is not at all common in real world fires, great sophistication in the mathematical modeling of classical fires is rarely warranted. An examination of pool‐like fires and pile fires of noncharring fuels has shown that the severity of such fires in the fire compartment, as characterized by the so‐called ‘fire severity product’, decreases slightly with an increase in ventilation. The principal danger presented by these fires, however, is not so much to the fire compartment itself as to the surrounding spaces.

An interesting feature of fires involving charring fuels, cellulosies in particular, is that the rate of consumption of fuel, the so‐called ‘rate of burning’, is practically independent of all process variables except ventilation. The severity of fires of cellulosics is, as a rule, much higher than that of fires of noncharring fuels. It exhibits a maximum at relatively low ventilations. From the point of view of spread of fire to the surrounding spaces, cellulosics are generally less dangerous than noncharring plastics. Fires involving cellulosics mixed with smaller amounts of noncharring plastics can be characterized as basically cellulosics fires, with a superimposed initial period of very high spread liability.
Ceiling heat transfer during fire plume and fire impingement
Authors: You H. Z. , Faeth G. M.
Published: May 2005

The impingement of turbulent fires and fire plumes on a horizontal ceiling was considered. Free flame heights, impinging flame lengths along the ceiling and ceiling heat fluxes were measured for both unconfined and confined ceilings. The study was limited to the initial stage of ceiling heating by fire under conditions where convection dominates the flow. Fire sources were simulated by burning liquid methanol, ethanol, 1‐propanol or n‐pentane from the top surface of a cylindrical wick. Test variables include fire heat release rate of 50–7890 W, ceiling diameters of 610 and 660 mm, ceiling heights of 58–940 mm, wick diameters of 10–107 mm and curtain wall lengths (for confined ceilings) as large as the ceiling height. Simplified models were employed to suggest expressions for data correlation. Flame lengths increased up to 40% when the ceiling was confined. Ceiling heat fluxes were relatively independent of position in the stagnation region (radius along ceiling <20% of the ceiling height). Heat fluxes in the stagnation region for plumes were 25–40% of those measured for impinging jets at comparable conditions. In the ceiling jet region, at larger distances from the point of impingement, the heat flux decreased with increasing radius, in agreement with other studies. Confinement tended to increase ceiling heat fluxes in both regions. Ceiling heat fluxes for impinging flames and plumes were approximately the same, for flame lengths along the ceiling up to 25% of the ceiling height; however, stagnation point heat fluxes decreased for longer flame lengths.
Developing flame retarded plastics: New guidance wanted
Authors: Fischer K.
Published: May 2005

The development of plastics with improved flame retardant properties is going through a phase of stagnation. Fire test concepts are following a new direction and the serial tests currently used do not adequately tie up with the development objective of reducing fire risks. In the short term no improvement in this situation is expected.
Smoke problems in buildings on fire: A TNO research project
Authors: Van Dijk H. A. L. , Twilt L. , Zorgman H.
Published: May 2005

The activities within the framework of TNO's research project on smoke problems in buildings on fire are reviewed. Two aspects will be dealt with extensively: smoke production and smoke movement. Furthermore, possible application of its finding will be discussed. The article reflects the state of the art at the end of 1978. In the meantime, the research programme has been concluded.
Measuring the leakage of door assemblies during standard fire exposures
Authors: Cooper Leonard Y.
Published: May 2005

The results of applying the tentative, high temperature, International Standards Organization test methods DP 5925 Part 3, which was developed to measure smoke leakage of door assemblies during the course of a standard fire endurance test, are reported. A critical analysis reveals that the basic objective of the test method is limited in its utility in that fire scenarios in high‐rise buildings may not be adequately simulated. Independent of this limitation, the analysis then identifies certain theoretical problems with the test method and its procedures. These lead to a conclusion that the test method is not generally reliable. An alternative test concept which appears to remove this limitation and all of its problems is described, and its development is advocated.
The thermal behaviour of lignins modified by chlorophosphazenes
Authors: Struszczyk Henryk
Published: May 2005

The thermal behaviour in air of lignins modified by chlorophosphazenes as well as that of the raw materials of lignins has been investigated using thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA). The thermogravimetry and derivative thermogravimetry studies of lignins modified by chlorophosphazenes have shown their thermal resistance to be relatively higher than that of the intital raw materials of lignins in concrete kraft lignin and sodium ligninosulfonate. The differential thermal studies have demonstrated that the thermal degradation of products investigated takes place via exothermic processes. The lignins modified by chlorophosphazenes have been shown to be thermal and flame‐resistant materials.
Normalized heat load: A key parameter in fire safety design
Authors: Harmathy T. Z. , Mehaffey J. R.
Published: May 2005

It is demonstrated that he normalized heat load is a suitable parameter for ranking various enclosure fires on a ‘potential for destruction’ scale. This parameter is convertible to the familiar fire resistance.
Correlations between four radiant panel tests used to classify the fire behaviour of floor coverings in the EC
Authors: Téphany H. , Martin J.
Published: May 2005

Tests related to reaction to fire of materials are different from one country to another in the EC, as are test‐based classifications. There is no valid equivalence between the classifications of materials. We examine another approach, which is to propose acceptance of materials for a specific application on the basis of the results recorded in tests performed in another country through correlation between data recorded in tests. This new approach is applied here to four tests using radiant panels for floor covering classifications in Belgium, France. West Germany and Italy. This report is based on the results recorded on fifteen materials in the four tests. The conclusion is that the researched correlation is good.
Rates of heat and smoke release of wood in an ohio state university calorimeter
Authors: Tran Hao C.
Published: May 2005

Particleboard, Douglas fir plywood and red oak were tested for heat and smoke release rates under different heat flux levels, piloted and unpiloted conditions, and vertical and horizontal orientations in an Ohio State University calorimeter. The chamber was instrumented to obtain heat release data by both the standard thermal and oxygen consumption methods simultaneously. Heat and smoke release data obtained by both methods are reported. The heat release rates by the thermal method are consistently lower than those by the oxygen consumption method. Variability in results is consistently lower using the oxygen consumption method. The heats of combustion calculated by oxygen consumption are close to those calculated from measurements with the oxygen bomb. The heat release rates measured on particleboard using the standard thermal method are in agreement with measurements on the same material in other Ohio State University calorimeters.
Correlation of flashpoint with molecular connectivity
Authors: Patil G. S.
Published: May 2005

A correlation has been obtained for the estimation of the closed‐cup flashpoint of hydrocarbons from their molecular connectivity indices. Estimated flashpoints are within a deviation of about 7.7% of reported values. A brief description of the calculation of the molecular connectivity index is given.
Feasibility study to demonstrate the potential of smoke hoods in simulated aircraft fire atmospheres: Development of the fire model
Authors: Paul K. T.
Published: May 2005

The subject of this paper is the development of a fire model producing smoke similar to that which could be anticipated from a burning passenger aircraft in the period before flashover. The simulated aircraft fire smoke was used to test filter and oxygen‐donating smoke hoods as part of the Accident Investigation Branch research programme initiated after the Boeing 737 fire at Manchester in 1985. A relatively simple approach was adopted in which materials used in passenger aircrafts cabins were burned in an enclosed room. The smoke hood exposure tests were then carried out in the same room. The fire model permitted the smoke hoods to be tested for 5‐min periods with an atmosphere approximating to that required and for longer periods with atmospheres with reduced concentrations of the more polar gases. Analytical procedures enabled both challenge atmospheres and filter penetration to be assessed. The evaluation of smoke hoods by Rapra Technology and British Coal demonstrated that filter smoke hoods were capable of providing protection (providing there was sufficient oxygen to sustain life), that carbon dioxide did not cause debilitation and that the heat produced by the oxidation of carbon monoxide was dissipated. Oxygen‐donating systems were also capable of providing protection for the duration of their oxygen supply but it was necessary to prevent the build‐up of carbon dioxide. Other important factors, such as the effectiveness of smoke hood to head seals and the effect of hood donning on aircraft evacuation times, have not been examined in this paper.
Material characteristics in the analysis of heated steel beams
Authors: Skowroński Wojciech
Published: May 2005

Beam fire tests are expensive and complicated. They may be replaced by calculations of the heated beam deflection by means of the method presented in this paper. The following material characteristics in the analysis of the deflection of beams during fire may be taken as fundamental: the steel creep characteristic at elevated temperatures, the modulus of elasticity and the coefficient of thermal expansion. According to the yield hinge theory, the yield stress is the criterion of failure of steel beams in fire. On the other hand, in the analysis of the deflection of the heated steel beams the influence of the yield stress is very small. The influence of the respective material characteristics on the heated steel beam's destruction is shown in this paper.
A laboratory‐scale gallery fire test on rubber conveyor belts with fabric skeletons
Authors: Nakagawa Yuichi , Komai Takeshi , Kohno Makoto
Published: May 2005

The authors have conducted a laboratory‐scale gallery fire test on nine different rubber conveyor belts with fabric skeletons. The interior of the gallery used in this test was 2.5 m long, 0.35 m wide and 0.35 m high. The fire test on each sample was conducted in the upward airflow of the inclined gallery as well as in the horizontal one, and both 60 mm and 90 mm wide specimens, whose length was about 1.5 m, were provided for each test. The test results were compared with those from some other small‐scale flammability tests; i.e. the small‐scale flame, the oxygen index and the hot plate ignition tests. In addition, some problems in the laboratory‐scale gallery fire test were also discussed. As a result, it has been found empirically that determination of both the time to ignition and the flame‐propagation speed could be significant in case the flame propagated over the whole length of the belt specimen in the gallery, so that the fire resistance of the belt samples could be classified in detail.
A study of the synergistic action of antimony oxide in fire‐retardant polyethylene
Authors: Yang Y. P. , Brewer D. G. , Venart J. E. S.
Published: May 2005

The fire‐retardant effectiveness of mixtures of hexabromocyclododecane (HBCD) and artimony oxide (Sb2O3) in polyethylene (PE) was examined utilizing differential thermal analysis (DTA), gas chromatography/mass spectroscopy (GC/MS) and limited oxygen index (LOI) techniques. It was determined that the normal practice of mixing Sb2O3 with HBCD induced a synergistic chemical reaction at 250°C whose main product, SbBr3, was responsible for enhanced fire retardancy. The mixing of SbBr3 directly into the PE produces a superior fire‐retardant polyethylene.
A study of the fire behaviour of polypropylene letter trays
Authors: McArthur N. A. , Jolliffe C. B.
Published: May 2005

A study of the fire behaviour of polypropylene plastics trays being considered for letter handling has been carried out. Various ignition sources and configurations of trays (both empty and filled with letters) were examined. In particular, stacks of trays contained in large steel‐mesh unit load devices (ULDs), protected by automatic sprinklers, were ignited and the progress of the fires, release of heat and smoke, and sprinkler activation recorded. It was found that, when examined singly or in stacks in scenarios which might be encountered in sorting areas and post offices, the trays made from fire‐retardant plastics were more difficult to ignite and took longer to become involved in fire than those made from standard grade plastics. The benefits of this slower build‐up fire with the retarded plastics formulation were reduced to some extent by the greater amounts of smoke released by the burning of the retarded plastics. For stacks of ULDs filled with trays, typical of a scenario in a mail exchange, the fire‐retardant plastics gave significant benefits in terms of life safety and fire damage to the trays and mail.
Some properties of hardened cement paste and reinforcing bars upon cooling from elevated temperatures
Authors: Dias W. P. S.
Published: May 2005

The post‐cooling properties of reinforced concrete constituents are of great relevance in the assessment of a structure for re‐use after fire. The expansive rehydration of dissociated calcium hydroxide on post‐cooling exposure to air can cause a total loss in strength if cement paste specimens are heated to and maintained at 400°C or above. The use of cement replacement agents can mitigate this effect. The strength and ductility of hot‐rolled mild steel and cold twisted steel on gradual cooling or quenching from various temperatures can be correlated with microstructural phenomena. There is a significant increase in strength and loss of ductility when both types of steel are quenched from temperatures above 723°C. Some practical implications of these properties are described, using examples of fire‐damaged structures.
PC‐Based product‐selection systems to enhance fire safety in construction
Authors: Zicherman Joseph B. , Frey David , Licht Richard , Jensen Kristen , Schommer Tony
Published: May 2005

Growing use of PCs in offices has been accompanied by increasing dependence on these systems to accomplish construction/specification and CAD‐based design tasks. The combination of product performance and characteristic data with PC‐based data storage and retrieval techniques is a newly developed example of this. Storage techniques utilized range from floppy disks on single systems through those loaded to hard disks or ROM systems, such as compact disks containing hundreds of megabytes of information. The combination of artificial intelligence techniques to aid the specifier are particularly useful where complex code‐mandated fire performance requirements exist. Using through penetration fire‐stopping technology as an example illustrates how such technology can assist architects, designers and specifiers. Computer workstations—both PCs and Macs—are increasingly finding their way into the design and specification work implicit in constructing buildings. Because of the growing complexity of requirements for fire performance of these structures, use of computer‐based systems to aid in choosing the right components to maintain fire safety levels makes good sense. Coupling artificial intelligence approaches—i.e. quasi‐expert systems—to selection of such products with viewing of drawings can reduce design professionals' work loads and provide increased advantages for designers, specifiers, enforcement officials and product manufacturers and marketers.