bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of the flammability reduction mechanism of polystyrene‐layered silicate nanocomposite: layered silicate reinforced carbonaceous char
Authors: Gilman Jeffrey W. , Harris Richard H. , Shields John R. , Kashiwagi Takashi , Morgan Alexander B. 
Published: March 2006

AbstractPolymer‐layered silicate nanocomposites (PLSNs) have been shown to have significantly reduced flammability. Based upon numerous studies to date, the proposed mechanism by which flammability reduction occurs is through formation of a silicate‐reinforced char layer that protects the underlying polymer. To further understand this condensed phase phenomena, polystyrene (PS) PLSN was studied during various states of decomposition. The materials were exposed to non‐oxidizing pyrolysis conditions using the National Institute of Standards and Technology (NIST) gasification apparatus. Samples were exposed for a range of pyrolysis times. The resulting partially decomposed PS PLSNs were analyzed by wide angle X‐ray diffraction (XRD), and thermogravimetric analysis (TGA). Sampling was done at different depths in each sample. The results show that as the PLSN was heated, the PS in the layered silicate galleries decomposed and volatilized, resulting in a collapse of the layer spacing, which yielded a stable silicate‐carbon char layer. This layered silicate or clay appears to catalyze formation of carbonaceous char which yields a clay reinforced carbon char layer with a d‐spacing of 1.3 nm; this unique structure forms quickly under pyrolysis conditions, and is stable even after extended pyrolysis times. TGA data suggest that there are two types of carbonaceous materials formed in the carbon phase of the clay‐carbon char; a carbon that can be decomposed and volatilized by heating in nitrogen, and a second fraction of material which requires more aggressive conditions, that is, heating (>700°C) in the presence of air. Copyright © 2006 John Wiley & Sons, Ltd.
Treatment of Wilms tumor relapsing after initial treatment with vincristine and actinomycin D: A report from the National Wilms Tumor Study Group
Authors: Green Daniel M. , Cotton Cecilia A. , Malogolowkin Marcio , Breslow Norman E. , Perlman Elizabeth , Miser James , Ritchey Michael L. , Thomas Patrick R.M. , Grundy Paul E. , D'Angio Giulio J. , Beckwith J. Bruce , Shamberger Robert C. , Haase Gerald M. , Donaldson Milton , Weetman Robert , Coppes Max J. , Shearer Patricia , Coccia Peter , Kletzel Morris , Macklis Roger , Tomlinson Gail , Huff Vicki , Newbury Robert , Weeks Douglas 
Published: March 2006

AbstractPurposeNWTS‐5 was a multi‐institutional clinical trial for patients less than 16 years of age at diagnosis with specific renal neoplasms who were diagnosed between August 1, 1995 and May 31, 2002. A uniform approach to the treatment of patients with relapse was employed.Patients and MethodsSeventy‐two patients who relapsed after immediate nephrectomy (stages I and II), initial chemotherapy with vincristine (VCR) and actinomycin D and no radiation therapy were registered on stratum B of the NWTS‐5 relapse protocol. Four patients were not evaluable: one due to insufficient data and three due to major protocol violations. Among the 68 remaining patients, one who was 19 years of age at initial diagnosis of Wilms tumor, five with bilateral Wilms tumor at diagnosis, three who developed a contralateral relapse, and one with persistent disease were not included in this analysis. Relapse treatment included surgical excision, when feasible, radiation therapy and alternating courses of VCR, doxorubicin and cyclophosphamide and etoposide and cyclophosphamide.ResultsThe outcomes of 58 patients were analyzed. The lung was the only site of relapse for 31 patients. Event‐free survival 4 years after relapse was 71.1% and 4‐year overall survival was 81.8% for all patients and were 67.8 and 81.0% for those who relapsed only to their lungs. The most frequent toxicities were hematological.ConclusionsThese results demonstrate that a significant proportion of children with Wilms tumor who relapse after initial treatment with VCR and actinomycin D can be successfully re‐treated. Pediatr Blood Cancer 2007;48:493–499. © 2006 Wiley‐Liss, Inc.
Interpolymer complexes of hydroxypropylmethylcellulose with polycarboxylic acids in aqueous solutions
Authors: Mangazbaeva Rauash A , Mun Grigoriy A , Nurkeeva Zauresh S , Khutoryanskiy Vitaliy V 
Published: March 2006

AbstractThe interactions between hydroxypropylmethylcellulose (HPMC) and poly(acrylic acid) (PAA) as well as poly(methacrylic acid) (PMAA) resulting in formation of hydrophobic interpolymer complexes (IPC) via hydrogen bonding have been studied in aqueous solutions in acidic medium. The formation of IPC of two different compositions (2:1 and 4:1) has been detected for complexes of PAA and HPMC. The critical pH values for complexation of HPMC with PAA and PMAA were determined by the turbidimetric method. It was found that PAA shows the lower complexation ability compared to PMAA due to the more hydrophobic nature of the latter polyacid. The temperature‐induced phase separation in HPMC–PAA solution mixtures depends greatly on the components ratio and PAA molecular weight. The complexation ability of hydroxypropylmethylcellulose with respect to poly(acrylic acid) was found to be similar to the complexation ability of methylcellulose, lower than that of hydroxypropylcellulose and higher than that of hydroxyethylcellulose. Copyright © 2006 Society of Chemical Industry
Synthesis of polypropylene graft copolymers from a hydroxyl‐groups‐containing polypropylene precursor via atom‐transfer radical polymerization
Authors: Zhang Liaoyun , Fan Guoqiang , Guo Cunyue , Dong Jin‐Yong , Hu Youliang , Huang Mingbao 
Published: March 2006

AbstractIsotactic polypropylene graft copolymers, isotactic[polypropylene‐graft‐poly(methyl methacrylate)] (i‐PP‐g‐PMMA) and isotactic[polypropylene‐graft‐polystyrene] (i‐PP‐g‐PS), were prepared by atom‐transfer radical polymerization (ATRP) using a 2‐bromopropionic ester macro‐initiator from functional polypropylene‐containing hydroxyl groups. This kind of functionalized propylene can be obtained by copolymerization of propylene and borane monomer using isospecific MgCl2‐supported TiCl4 as catalyst. Both the graft density and the molecular weights of i‐PP‐based graft copolymers were controlled by changing the hydroxyl group contents of functionalized polypropylene and the amount of monomer used in the grafting reaction. The effect of i‐PP‐g‐PS graft copolymer on PP‐PS blends and that of i‐PP‐g‐PMMA graft copolymer on PP‐PMMA blends were studied by scanning electron microscopy. Copyright © 2006 Society of Chemical Industry
Biodegradable aliphatic thermoplastic polyurethane based on poly(ε‐caprolactone) and L‐lysine diisocyanate
Authors: Hassan Mohammad K. , Mauritz Kenneth A. , Storey Robson F. , Wiggins Jeffrey S. 
Published: March 2006

AbstractA biodegradable aliphatic thermoplastic polyurethane based on L‐lysine diisocyanate and 1,4‐butanediol hard block segments, and 2000 g/mol poly(ε‐caprolactone) diol soft block segments was synthesized. The resulting polymer was a tough thermoplastic with ultimate tensile strength of 33 MPa and elongation of 1000%. The polymer displayed classic segmented thermoplastic elastomer morphology with distinct hard block and soft block phases. Thermal and dynamic mechanical analyses determined that the material has a useful service temperature range of around −40 °C to +40 °C, making it an excellent candidate for low‐temperature elastomer and film applications, and potentially as a material for use in temporary orthopedic implant devices. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2990–3000, 2006
Chiral soluble polymers and microspheres for enantioselective crystallization
Authors: Menahem Tali , Mastai Yitzhak 
Published: March 2006

AbstractA series of chiral polymers based on poly(N‐acryl) amino acids was synthesized using a convergent synthetic approach. These chiral polymers have been used as chiral additives to induce enantioselective crystallization of racemic or conglomerate amino acids in solutions. These polymeric additives showed strong capabilities to enhance highly enantioselective resolution during the crystallization of amino acids. In addition, these polymers caused unusual modifications of amino acid crystal morphologies. Furthermore, spherical microparticles of those same chiral polymers were also shown active in similar chiral discriminations during amino acid crystallizations occurring on microparticle surfaces. Our study demonstrates the high potential of chiral polymers and microparticles to resolve amino acids throughout crystallization processes. High enantiomeric excesses in one targeted enantiomer of amino acids can also be maximized via time‐dependent kinetic control of crystallizations. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3009–3017, 2006
Comprehensive 2D NMR analysis: Acrylonitrile/ethyl methacrylate copolymers synthesized by ATRP at ambient temperature
Authors: Brar A. S. , Saini Tripta 
Published: March 2006

AbstractCopolymerization of acrylonitrile and ethyl methacrylate using atom transfer radical polymerization (ATRP) at ambient temperature was carried out under optimized reaction conditions using 2‐bromopropionitrile as initiator and CuBr/2,2′‐bipyridine as the catalyst system. The copolymer composition, obtained from 1H NMR spectra, were used to determine the monomer reactivity ratios (rA = 0.68 and rE = 1.75) involved in ATRP. Two‐dimensional NMR (heteronuclear single quantum correlation and total correlated spectroscopy) experiments were employed to resolve the highly overlapping and complex 1H and 13C{1H} NMR spectra of copolymers. The complete spectral assignments of the quaternary carbons viz. carbonyl and nitrile carbons were done with the help of heteronuclear multiple bond correlation spectra. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2955–2971, 2006
Grafting of polymers onto and/or from silica surface during the polymerization of vinyl monomers in the presence of γ‐ray‐irradiated silica
Authors: Tsuchida Akiko , Suda Makoto , Ohta Masatoshi , Yamauchi Takeshi , Tsubokawa Norio 
Published: March 2006

AbstractThe effects of radicals on silica surface, which were formed by γ‐ray irradiation, on the polymerization of vinyl monomers were investigated. It was found that the polymerization of styrene was remarkably retarded in the presence of γ‐ray‐irradiated silica above 60 °C, at which thermal polymerization of styrene is readily initiated. During the polymerization, a part of polystyrene formed was grafted onto the silica surface but percentage of grafting was very small. On the other hand, no retardation of the polymerization of styrene was observed in the presence of γ‐ray‐irradiated silica below 50 °C; the polymerization tends to accelerate and polystyrene was grafted onto the silica surface. Poly(vinyl acetate) and poly(methyl methacrylate) (MMA) were also grafted onto the surface during the polymerization in the presence of γ‐ray‐irradiated silica. The grafting of polymers onto the silica surface was confirmed by thermal decomposition GC‐MS. It was considered that at lower temperature, the grafting based on the propagation of polystyrene from surface radical (“grafting from” mechanism) preferentially proceeded. On the contrary, at higher temperature, the coupling reaction of propagating polymer radicals with surface radicals (“grafting onto” mechanism) proceeded to give relatively higher molecular weight polymer‐grafted silica. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2972–2979, 2006
Responses to inhaled bronchodilators in infancy are not linked with asthma in later childhood
Authors: Hyvärinen Mari K. , Kotaniemi‐Syrjänen Anne , Reijonen Tiina M. , Korhonen Kaj , Kiviniemi Vesa , Korppi Matti 
Published: March 2006

AbstractMany doctors consider wheezing infants and young children who respond to β‐adrenergic agents to be asthmatics, or at least at risk for later asthma. The aim of this study was to compare responses to inhaled albuterol and racemic epinephrine in infancy between children with and without asthma later in childhood. In a crossover study setting, 100 acutely wheezing infants aged less than 24 months were randomized to receive inhalations of either racemic epinephrine and placebo, or albuterol and placebo. Clinical evaluation consisted of measurements of respiratory rate, heart rate, and oxygen saturation, and clinical assessment of the respiratory distress assessment instrument (RDAI) score, consisting of wheezing and chest indrawings. The asthma status of the children was evaluated at three clinical follow‐up visits, at 4.0, 7.2, and 12.3 (median) years of age. Responses to bronchodilating agents, when respiratory rates and RDAI scores were used as outcome measures, were not different in future asthmatics compared to nonasthmatics. However, oxygen saturation was significantly higher after albuterol inhalation in children who had asthma at all three visits (92.67% confidence interval (CI), 91.39–93.96) than in those without asthma at these visits (92.52% CI, 91.79–93.25), but lower, correspondingly, after racemic epinephrine (91.97% CI, 90.74–93.19 vs. 93.04% CI, 92.29–93.79) and placebo (91.38% CI, 90.49–92.28 vs. 93.12% CI, 92.60–93.65) inhalations (P = 0.04). In conclusion, we were not able to confirm that future asthmatics respond better than future nonasthmatics to bronchodilating agents during wheezing in infancy. More studies are needed to characterize the subset of infants who benefit from bronchodilating treatment in infancy. Pediatr Pulmonol. 2006; 41:420–427. © 2006 Wiley‐Liss, Inc.
Expired tidal volumes measured by hot‐wire anemometer during high‐frequency oscillation in preterm infants
Authors: Zimová‐Herknerová Magdalena , Plavka Richard 
Published: March 2006

AbstractWe sought to determine the normocapnic values of expiratory tidal volume measured by hot‐wire anemometer, and to evaluate how often expiratory tidal volume exceeds estimated anatomical dead space during high‐frequency oscillatory ventilation (HFOV) in preterm infants. We also sought to determine the relationship between expiratory tidal volume and other respiratory parameters. The neonatal respiration monitor SLE 2100 VPM, a hot‐wire anemometer, was used to measure expired tidal volume (VT,E) in patients ventilated by the Sensormedics 3100A during routine clinical use of HFOV. Two hundred and fourteen simultaneous measurements of PaCO2, VT,E, fraction of inspired oxygen (FiO2), continuous distending pressure (CDP), frequency, and amplitude were obtained from 28 patients. The median birth weight was 852 g (range, 435–3,450 g), and median gestational age was 27.2 weeks (range, 23.3–41.0 weeks). One hundred and eighteen (55%) normocapnic measurements, 42 (20%) hypocapnic measurements, and 54 (25%) hypercapnic measurements were recorded in which the median VT,E was 1.67 ml/kg (95% confidence interval (CI), 1.55–1.79), 1.94 ml/kg (95% CI, 1.74–2.14), and 1.54 ml/kg (95% CI, 1.42–1.66), respectively. The measured VT,E exceeded 2.0 ml/kg in 30 instances of normocapnic VT,E (14%) and 54 of all VT,E (25%), and 3 ml/kg only in 7 (3%) and 11 (5%) instances of normocapnic and all VT,E. There was a significant difference in median normocapnic VT,E obtained when FiO2 was between 0.21–0.35, compared to values obtained when FiO2 was 0.36–1.0 (1.61 ml/kg (95% CI, 1.52–1.70) vs. 2.06 ml/kg (95% CI, 1.93–2.19), P < 0.002). The calculated values of PaCO2 between 35–47, using the calculated regression equation for prediction of PaCO2 (mmHg), correctly predicted normocapnic values in 60% of measurements. Values >47 should predict hypercapnia in 81% of cases. In conclusion, expired tidal volume measurement by heated double‐wire anemometer sensor is feasible, provides useful real‐time information about tidal volume changes, and may improve the clinical management of HFOV. Pediatr Pulmonol. 2006; 41:428–433. © 2006 Wiley‐Liss, Inc.
Intrapulmonary application of a 5‐lipoxygenase inhibitor using surfactant as a carrier reduces lung edema in a piglet model of airway lavage
Authors: Ankermann Tobias , Reisner Anja , Wiemann Tina , Koehler Heike , Krams Matthias , Krause Martin F. 
Published: March 2006

AbstractLeukotriene‐generated effects on microvascular integrity and polymorphonuclear leukocytes (PMNL) play a key role in the inflammatory process of the alveolar‐capillary unit in neonatal acute respiratory distress syndrome. We asked if intrapulmonary application of MK886, a 5‐lipoxygenase inhibitor, and the use of a porcine surfactant preparation (Curosurf™) as a carrier substance would improve lung function in a neonatal piglet model of airway lavage. Anesthetized, mechanically ventilated newborn piglets (n = 19) underwent repeated airway lavage to induce acute lung injury. Piglets then received either surfactant alone (S, n = 6), or MK886 admixed with surfactant (S + MK, n = 7), or an air‐bolus injection as control (C, n = 6). Measurements of gas exchange, lung function, extravascular lung water (EVLW), cell counts, and leukotriene B4 (LTB4) concentrations in bronchoalveolar lavage fluid (BAL) were performed during 6 hr of mechanical ventilation. Arterial oxygen partial pressure (PaO2) (S, 13.8 ± 4.2 kPa, vs. S + MK, 20 ± 6.6; P < 0.05), functional residual capacity (S, 15.1 ± 6.8 ml/kg, vs. S + MK, 18.8 ± 3.7 ml/kg; P < 0.05), and EVLW (S, 29 ± 14 ml/kg, vs. S + MK 24 ± 4 ml/kg; P < 0.05) were significantly improved in the MK886 group. This clinical effect was linked with a decrease in LTB4 concentration in BAL (S, 3.5 (1.9–5.4) pg/ml, vs. S + MK, 1.6 (0.7–4.7) pg/ml; P < 0.05) and an increase in IL‐8 (S, 2,103 (852–4,243) pg/ml, vs. S + MK, 3,815 (940–26,187) pg/ml; P < 0.05). PMNL counts in BAL were reduced (S, 570 ± 42 cells/ml, vs. 275 ± 35 cells/ml; P < 0.05). In conclusion, intrapulmonary application of the 5‐lipoxygenase inhibitor MK886 with surfactant as a carrier improves lung function by decreasing EVLW as the main response to LTB4 reduction. Pediatr Pulmonol. 2006; 41:452–462. © 2006 Wiley‐Liss, Inc.
Exhaled carbon monoxide levels in school‐age children with episodic asthma
Authors: Ohara Yoichiro , Ohrui Takashi , Morikawa Toshio , He Mei , Yasuda Hiroyasu , Yamaya Mutsuo , Sasaki Hidetada 
Published: March 2006

AbstractCarbon monoxide (CO) can be detected in exhaled air and is increased in adult and childhood persistent asthmatic patients. However, little is known about the exhaled CO concentration in episodic childhood asthma. This study aimed to clarify whether measurement of exhaled CO is useful in monitoring disease activity in children with episodic asthma. We measured exhaled CO concentration by modified Micro‐Smokerlyzer in 217 elementary school children (132 boys; mean age, 10 ± 1 (SE) years; range, 9–12 years), in whom 29 had infrequent episodic asthma without current exacerbations. We also measured exhaled CO concentrations in 22 children with episodic asthma (13 boys; mean age, 10 ± 3 years; range, 8–12 years), who had acute mild asthmatic attacks during examination. In these patients with mild asthmatic attacks, exhaled CO was measured both before and after combination therapy with salbutamol and sodium cromoglycate (SCG) by powered nebulizer. Among 217 schoolchildren, exhaled CO levels in infrequent episodic asthmatic children (1.1 ± 0.1 parts per million (ppm), n = 29) were not significantly different from those in healthy schoolchildren (1.0 ± 0.1 ppm, n = 188, P > 0.68). The exhaled CO concentrations during asthma attacks in children with episodic asthma were significantly higher (5.1 ± 0.4 ppm, n = 22) compared with those in healthy children (P < 0.001) or those in asymptomatic asthmatic children (P < 0.001). The elevated exhaled CO levels were significantly decreased after inhalation therapy of a combination of salbutamol and SCG (3.2 ±  0.5 ppm, n = 22, P < 0.02). In conclusion, exhaled CO levels were significantly elevated during acute asthma exacerbations, and partially recovered after treatment with β2‐agonist and SCG in children with mild episodic asthma. These findings indicate that measurement of exhaled CO might provide another noninvasive measurement of asthma exacerbations that would be suitable for use in children with acute mild episodic asthma. Pediatr Pulmonol. 2006; 41:470–474. © 2006 Wiley‐Liss, Inc.
Haemophilus influenzae type b vaccination and reported atopic disorders in 8–12‐year‐old children
Authors: Bernsen Roos M.D. , Koes Bart W. , de Jongste Johan C. , van der Wouden Johannes C. 
Published: March 2006

AbstractBecause Haemophilus influenzae type b (Hib) vaccination was added recently to most vaccination programs, no conclusive data on the relationship with atopic disorders are yet available. We sought to assess the risk of atopic disorders at ages 8–12 years associated with Hib vaccination in the first year of life, in addition to diphtheria‐tetanus‐pertussis‐inactivated poliomyelitis vaccination (DTP‐IPV) and other childhood vaccinations. Parents of 1,201 children attending Orthodox Reformed (Protestant) primary schools in The Netherlands returned questionnaires reporting data on vaccination status, atopic symptoms and physician‐diagnosed lifetime atopic disorders (asthma, hay fever, eczema, and food allergy), and possible confounders. This study was conducted within the framework of a larger study on the relationship between the DTP‐IPV and reported atopic disorders. The adjusted odds ratio of any atopic disorder (Hib‐vaccinated/unvaccinated) was 1.09 (95% confidence interval (CI), 0.79–1.50). For asthma, hay fever, eczema, and food allergy, the results were, respectively, 0.89 (95% CI, 0.55–1.43), 0.94 (95% CI, 0.47–1.90), 1.09 (95% CI, 0.75–1.58), and 0.68 (95% CI, 0.38–1.19). In conclusion, in the Dutch population, there is no indication for a higher risk of reported physician‐diagnosed atopic disorders at primary schools age after Hib vaccination in the first year of life, in addition to other vaccinations. Pediatr Pulmonol. 2006; 41:463–469. © 2006 Wiley‐Liss, Inc.
Differences in prevalence of asthma, rhinitis, and eczema between parental and self‐completed questionnaires in adolescents
Authors: Mallol Javier , Castro‐Rodríguez José A. 
Published: March 2006

AbstractThis study was undertaken to compare, for the first time in a developing country, the prevalence of asthma, rhinitis, and eczema in children aged 13–14 years when questionnaires from the International Study of Asthma and Allergies in Childhood (ISAAC) were independently completed by children and parents. A random sample of 3,178 children completed the ISAAC questionnaire at school, while in another sample of 3,387 children, the questionnaire was completed by their parents at home. The prevalence of asthma, rhinitis, and eczema symptoms was significantly higher when questionnaires were completed by adolescents themselves rather than by the parents, particularly for those symptoms that could be better perceived by children or that were more severe, e.g., wheezing with exercise, severe episodes of wheezing, nocturnal cough, and awaking with wheezing in the last 12 months. The diagnosis of hay fever and eczema was also reported more frequently by adolescents compared to their parents. The prevalence of asthma ever and wheezing in the last 12 months was not significantly different between the two samples. In a randomly selected subset of 550 pairs where adolescents and parents came from the same family, asthma ever had the highest agreement (kappa = 0.72, 95% CI: 0.64–0.80), but agreement was poor for rhinitis and eczema ever. In conclusion, the prevalence of asthma, rhinitis, and eczema symptoms varied according to whether the information was reported by independent samples of adolescent or parents. However, the prevalence of wheezing in the last 12 months and asthma ever was quite similar between adolescents and parents, suggesting that these questions are crucial for assessing asthma in epidemiological studies. Pediatr Pulmonol. 2006; 41:482–487. © 2006 Wiley‐Liss, Inc.