bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphology and Conformation Analysis of Self‐Assembled Triblock Copolymer Melts
Authors: Abu‐Sharkh Basel , AlSunaidi Abdullah 
Published: July 2006

AbstractSummary: We used the dissipative particle dynamics method to simulate the self‐assembly of symmetric triblock copolymers of the type ABA. Depending on the volume fraction of the end blocks fA, several mesophases including lamellar, perforated lamellar, gyroid, hexagonal cylinders and bcc spherical micelles were obtained. The order‐disorder transition (ODT) at fA = 0.5 was found to be about χN = 19.8. The ODT for the cylindrical mesophase at symmetrical points on the phase diagram had different values, indicating asymmetry in the phase diagram. We were also able to estimate the bridge fraction in the different mesophases. They range from about 0.44 for the lamellar mesophase to about 0.75 for the spherical micelles. Our simulation results are in good agreement with previously reported theoretical calculations and experimental observations.The hexagonal cylinders generated with the A6B4A6 copolymer.magnified imageThe hexagonal cylinders generated with the A6B4A6 copolymer.
Selection of Catalyst for the Esterification Step of the PPT Polymerization Process
Authors: Mitra Kishalay , Majumdar Saptarshi 
Published: July 2006

AbstractSummary: TBOT is a proven catalyst for the esterification step of the PPT polymerization process. Previous studies have shown that the performance of TBOT is superior in terms of the enhanced degree of polymerization and shorter processing time. However, one interesting aspect which has not yet been investigated is whether with different process objectives, like by‐product minimization and controlled growth of desired functional groups, any other catalyst offers any increase in process performance. The present study gives a detailed process analysis through different sets of optimized operations, which consists basically of searching for other catalytic options for process improvements. A well validated kinetic model for the esterification step of the PPT polymerization process and the advanced Real‐Coded NSGA‐II optimization routine have been used in this study. It can be seen that with all the process considerations, such as maximization of the degree of polymerization, minimization of processing time and the enhanced controlled growth of desired functional groups and minimization of by‐products, the Zn‐based catalyst can replace the conventional Ti‐based catalyst. An Sn‐based catalyst was also found to be able to compete with these two catalysts in some cases.Optimized Pareto plot for a study on the 4 objectives case for various catalysts. The Zn‐based catalyst outperforms the others.magnified imageOptimized Pareto plot for a study on the 4 objectives case for various catalysts. The Zn‐based catalyst outperforms the others.
HPLC quantification of alkaloids from Haplophyllum extracts and comparison with their cytotoxic properties
Authors: Fiot Julien , Jansen Olivia , Akhmedjanova Valentina , Angenot Luc , Balansard Guy , Ollivier Evelyne 
Published: July 2006

AbstractAn efficient system for the analysis of total alkaloids extracted from the aerial parts from different species of genus Haplophyllum (Rutaceae) by HPLC on a reversed‐phase column is described. The HPLC method described was validated for its specificity, linearity and precision using external standards (haplopine, skimmianine and haplamine). The chromatographic conditions allowed the separation of alkaloids and the quantification of haplopine, skimmianine and haplamine in different samples of species of Haplophyllum collected in Uzbekistan. The alkaloidal contents of samples were compared with their in vitro cytotoxic properties against two cancer cell lines (HeLa and HCT‐116). The cytotoxicity of extracts was correlated with the concentration of haplopine, skimmianine or haplamine in aerial parts of species of Haplophyllum. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of the defence phosphoproteome of Arabidopsis thaliana using differential mass tagging
Authors: Jones Alexandra M. E. , Bennett Mark H. , Mansfield John W. , Grant Murray 
Published: July 2006

AbstractDespite recent advances in proteomic technologies, quantitative analysis of the proteome remains a challenging task. Phosphorylation of proteins is central to signal transduction pathways and plays an important role in plant defence against pathogens, although the immediate targets of kinases remain elusive. Determining changes in the phosphoproteome during the defence response is a major goal in molecular plant pathology. In this first description of the novel mass tagging strategy (iTRAQ™ Applied Biosystems) applied to plant pathogen interactions, we describe early changes to the phosphoproteome of Arabidopsis thaliana during the defence response to Pseudomonas syringae pv. tomato DC3000. We identified five proteins which showed reproducible differences between a control and three different bacterial challenges, thus identifying proteins potentially phosphorylated as part of a plant basal defence response. Four of the five proteins a dehydrin, a putative p23 co‐chaperone, heat shock protein 81 and a plastid‐associated protein (PAP)/fibrillin, are known to be phosphorylated or have potential phosphorylation sites. One further protein, the large subunit of Rubisco, showed a significant difference between tissue undergoing the hypersensitive response and a basal defence response. We document the reproducibility, utility and problems associated with this approach.
Electrosyntheses of high‐quality freestanding poly(fluorene‐co‐3‐methylthiophene) films with tunable fluorescence properties
Authors: Wei Zhenhong , Xu Jingkun , Pu Shouzhi , Du Yukou 
Published: July 2006

AbstractThe copolymerization of 3‐methylthiophene (MeT) and fluorene (FE) was successfully achieved in boron trifluoride diethyl etherate by the direct anodic oxidation of the monomer mixtures on a platinum electrode. The optimal feed ratio together with the best suitable potential for their copolymerization was determined. The as‐formed copolymer films, which were copolymerized with a feed ratio of FE/MeT = 2:1 at a constant potential of 1.3 V (vs a saturated calomel electrode), had the advantages of both poly(3‐methylthiophene) and polyfluorene, such as good electrochemical behavior, high conductivity, excellent thermal stability, and high film quality. The structure of the copolymer was investigated with ultraviolet–visible, infrared spectroscopy, and thermal analysis. Fluorescence spectroscopy studies revealed that the dedoped copolymer film in the solid state was a good blue‐light emitter with a strong emission at 435 nm and a shoulder at 459 nm. The emitting properties of the copolymer could be tuned by parameters during the electrochemical polymerization, such as the applied potential and monomer feed ratio. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4904–4915, 2006
Amphiphilic diblock star polymer catalysts via atom transfer radical polymerization
Authors: Dichtel William R. , Baek Kyung‐Youl , Fréchet Jean M. J. , Rietveld Ivo B. , Vinogradov Sergei A. 
Published: July 2006

AbstractDiblock star polymers were synthesized via atom transfer radical polymerization from a palladium porphyrin macroinitiator. The arms of the star polymers had an amphiphilic design, with the central Pd‐porphyrin surrounded by a relatively hydrophobic block of poly(butyl acrylate) and terminated by a hydrophilic block of poly(oligoethyleneglycol monomethylether monomethacrylate). The size of both the interior and exterior blocks of the polymer arms were tuned over a wide range of molecular weights with the exterior block used to solubilize the stars in polar media. The star polymers showed enhanced reactivity in the oxidation of 2‐furaldehyde relative to a small molecule porphyrin, suggesting that the polymer backbone aids with catalytic turnover. Oxygen diffusion studies indicate that the polymer backbone shields the porphyrin excited state from oxygen quenching. Shielding is independent of molecular weight and polymer composition, but it is not pronounced enough to retard the rate of singlet oxygen generation under preparative photooxidation conditions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4939–4951, 2006
Association of pulmonary artery agenesis and hypoplasia of the lung
Authors: Vitiello Renato , Pisanti Chiara , Pisanti Antonello , Silberbach Michael 
Published: July 2006

AbstractPulmonary artery agenesis and hypoplasia of the homolateral lung occasionally occurs as an isolated lesion, but more often has associated congenital cardiac anomalies. We present a case where pulmonary artery agenesis was the sole lesion in an asymptomatic child. Pulmonary artery agenesis should be suspected in asymptomatic patients if a plain chest X‐ray shows asymmetric lung fields, lung hypoplasia, or hyperinflation of the contralateral lung. Echocardiography is the best tool to establish the diagnosis. In our opinion, invasive procedures, such as cardiac catheterization, may be postponed if there is no echocardiographic evidence of pulmonary hypertension. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Effects of antenatal corticosteroid treatment on pulmonary ventilation and circulation in neonatal lambs with hypoplastic lungs
Authors: Suzuki Keiji , Hooper Stuart B. , Wallace Megan J. , Probyn Megan E. , Harding Richard 
Published: July 2006

AbstractOur aim was to determine whether antenatal corticosteroids improve perinatal adaptation of the pulmonary circulation in lambs with lung hypoplasia (LH). LH was induced in 12 ovine fetuses between 105 and 140 days gestation (term ∼147 days); in 6 of these the ewe was given a single dose of betamethasone (11.4 mg im) 24 hr before delivery (LH + B). All lambs, including a control group (n = 6), were delivered at ∼140 days and ventilated for 2 hr during which arterial pressures, pulmonary blood flow (PBF), and ventilating pressure and flow were recorded. During ventilation, respiratory system compliance was lower in both LH + B and LH groups than in controls. Pulmonary vascular resistance (PVR) was lower in LH + B lambs than in LH lambs and similar to controls; PBF was reduced in LH lambs but was restored to control levels by betamethasone. The mean density of small arteries of LH + B lambs was similar to that of LH lambs (P = 0.06) and lower than in controls; the thickness of the media of small pulmonary arteries from LH + B lambs was similar to that in LH lambs and thicker than in controls. VEGF mRNA levels were not different between groups. PDGF mRNA levels in LH + B lambs were higher than in LH lambs; a similar trend (P = 0.06) was seen for PECAM‐1. SP‐C mRNA levels were greater in both LH and LH + B lambs than in controls. Effects of betamethasone were greater on indices of pulmonary circulation than ventilation. We conclude that a single dose of maternal betamethasone 24 hr prior to birth has significant favorable effects on the postnatal adaptation of the pulmonary circulation in lambs with LH. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Exhaled nitric oxide in the management of childhood asthma: A prospective 6‐months study
Authors: Fritsch Maria , Uxa Sabine , Horak Friedrich , Putschoegl Bettina , Dehlink Eleonora , Szepfalusi Zsolt , Frischer Thomas 
Published: July 2006

AbstractFractional exhaled nitric oxide (FeNO) is elevated in asthma and reflects eosinophilic airway inflammation. The aim of this prospective, randomized, single‐blind study was to examine whether the inclusion of repeated FeNO measurements into asthma monitoring leads to an improvement in asthma outcome. Forty‐seven children with mild to moderate asthma were allocated to a FeNO group (n = 22) and to a control group (n = 25). In the FeNO group therapy was based on symptoms, β‐agonist use, lung function, and FeNO whereas in the control group therapy was based on symptoms, β‐agonist use and lung function only. Patients performed five visits in 6 weeks intervals. Frequency of respiratory symptoms, β‐agonist use, FEV1% predicted and the frequency of exacerbations were similar between groups. Patients in the FeNO group received higher doses of inhaled corticosteroids (ICS) (control group: median (interquartile range): 241 µg (26–607 µg); FeNo group: 316 µg (200–500 µg) and had significantly higher MEF50% predicted (control group: median (interquartile range): 68.5% (55.8–83.1%); FeNO group: 83.2% (62.9%–98.3%). At a cut‐off point of 22.9 ppb FeNO the best predictive value for exacerbations with a sensitivity of 80% and specificity of 60% was found. Significant relationships were observed between FeNO and dose of ICS (β = −8.77; P < 0.002), β‐agonist use 2 weeks prior to a visit (β = 0.11; P < 0.05), asthma symptoms (β = 0.02; P < 0.0001), and bronchial hyperresponsiveness (β = 0.04; P = 0.02). In conclusion, FeNO was related to important markers of asthma control. A therapy regimen aimed at lowering FeNO in children with asthma improved parameters of small airway function, but was not able to improve clinical markers of asthma control. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Prevalence and clinical characteristics of human metapneumovirus infections in hospitalized infants in Spain
Authors: García‐García M.L. , Calvo C. , Pérez‐Breña P. , De Cea J.M. , Acosta B. , Casas I. 
Published: July 2006

AbstractHuman metapneumovirus (hMPV), a condition recently described in the Netherlands, causes lower respiratory infections, particularly in young children and among the elderly. The objective of this study was to describe the characteristics of hMPV infections in hospitalized infants <2 years of age and to compare them to those of infections caused by respiratory syncytial virus (RSV). A prospective study was conducted on the clinical characteristics of infants admitted to hospital for respiratory infection through 5 years. Simultaneous detection of influenza A, B, and C viruses, RSV, and adenoviruses was performed in clinical samples by multiple reverse transcription nested‐PCR assay. The presence of hMPV was tested in all samples using two separate RT‐PCR tests. Some respiratory virus was detected in 70.5% of the 1,322 children included in the study. hMPV was found in 101 of the positive nasopharyngeal aspirates (10.8%), and was the most common virus after RSV and rhinovirus. Peak incidence was found in March. Over 80% of children were <12 months. The more common diagnoses were bronchiolitis (49.5%) and recurrent wheezing (45.5%). Fifty‐four percent of cases required oxygen therapy and, one percent, assisted ventilation. Thirty percent were co‐infections, with clinical characteristics indistinguishable from single infections. Seventy‐one hMPV single infections were compared to 88 RSV single infections. hMPV infections were significantly more frequent than RSV in infants older than 6 months (P = 0.04). Recurrent wheezing was diagnosed more frequently in hMPV patients (P = 0.001). All other variables tested were similar, in both groups. hMPV was the third most frequent virus after RSV and rhinovirus in infants <2 years of age, hospitalized for respiratory infection, and was associated with bronchiolitis and recurrent wheezing. hMPV predominantly occurred in spring. Co‐infections were frequent and clinically similar to single infections and RSV infections. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Synchronized nasal intermittent positive pressure ventilation (SNIPPV) decreases work of breathing (WOB) in premature infants with respiratory distress syndrome (RDS) compared to nasal continuous positive airway pressure (NCPAP)
Authors: Aghai Zubair H. , Saslow Judy G. , Nakhla Tarek , Milcarek Barry , Hart James , Lawrysh‐Plunkett Robyn , Stahl Gary , Habib Robert H. , Pyon Kee H. 
Published: July 2006

AbstractSynchronized nasal intermittent positive pressure ventilation (SNIPPV) is non‐invasive respiratory support that delivers ventilator breaths via the nasal prongs. We hypothesized that SNIPPV is more effective than nasal continuous positive airway pressure (NCPAP) in premature neonates due to decreased work of breathing (WOB). Fifteen infants (BW: 1,367 ± 325 g, GA: 29.5 ± 2.4 weeks) were studied on (a) NCPAP at 5 cmH2O (NCPAP5) and (b) three increasing SNIPPV settings achieved by NCPAP5 with additional delivered peak inspiratory pressures (PIP) of 10, 12, and 14 cmH2O. Tidal volumes and transpulmonary pressures were estimated via calibrated respiratory inductance plethysmography (RIP) and esophageal pressures, respectively. Inspiratory (WOBinsp), resistive (RWOB), and elastic (WOBE) components of WOB were calculated using standard methods. Compared to NCPAP5, (a) WOBinsp and RWOB were significantly lower with SNIPPV12, and were similarly lower with SNIPPV14 and (b) WOBE was significantly lower only with SNIPPV14. WOB components did not differ significantly for the three SNIPPV settings. Tidal volume, respiratory rate (RR), minute ventilation, compliance, and phase angle were similar for all four measurements. In conclusion, compared to NCPAP, the addition of ventilator‐delivered PIP during SNIPPV decreases WOB in premature infants. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Construction and Optimality of a Special Class of Balanced Designs
Authors: Barone Stefano , Lombardo Alberto 
Published: July 2006

AbstractThe use of balanced designs is generally advisable in experimental practice. In technological experiments, balanced designs optimize the exploitation of experimental resources, whereas in marketing research experiments they avoid erroneous conclusions caused by the misinterpretation of interviewed customers. In general, the balancing property assures the minimum variance of first‐order effect estimates. In this work the authors consider situations in which all factors are categorical and minimum run size is required. In a symmetrical case, it is often possible to find an economical balanced design by means of algebraic methods. Conversely, in an asymmetrical case algebraic methods lead to expensive designs, and therefore it is necessary to adopt heuristic methods. The existing methods implemented in widespread statistical packages do not guarantee the balancing property as they are designed to pursue other optimality criteria. To deal with this problem, the authors recently proposed a new method to generate balanced asymmetrical designs aimed at estimating first‐ and second‐order effects. To reduce the run size as much as possible, the orthogonality cannot be guaranteed. However, the method enables designs that approach the orthogonality as much as possible (near orthogonality). A collection of designs with two‐ and three‐level factors and run size lower than 100 was prepared. In this work an empirical study was conducted to understand how much is lost in terms of other optimality criteria when pursuing balancing. In order to show the potential applications of these designs, an illustrative example is provided. Copyright © 2006 John Wiley & Sons, Ltd.
Planning and Optimization of a Numerical Control Machine in a Multiple Response Case
Authors: Berni Rossella , Gonnelli Claudia 
Published: July 2006

AbstractThis paper focuses on a specific case of experimental planning and optimization in a multiresponse case. Particularly, our attention is dedicated to a numerical control machine and our final goal is to improve this machine's measurement accuracy for a general dental implant. This work substantially aims at addressing two issues: the optimization methods in the presence of more response variables and the related problem of weighting according to the actual importance of these variables. About simultaneous optimization, we suggest an improvement by a new function which takes care of location and dispersion effects. Copyright © 2006 John Wiley & Sons, Ltd.
A weighted logistic regression model for estimation of recurrence of adenomas
Authors: Hsu Chiu‐Hsieh , Green Sylvan B. , He Yulei 
Published: July 2006

AbstractIn a colorectal polyp prevention trial, some participants might have their follow‐up colonoscopy conducted before the scheduled time (i.e. at the end of the trial). This results in variable follow‐up lengths for participants and the data of recurrence status at the end of the trial can be considered as current status data. In this paper, we use a weighted logistic regression model to estimate recurrence rate of adenoma data at the end of the trial. The weights are used to adjust for variable follow‐up. We show that logistic regression tends to underestimate recurrence rate. In a simulation study, we show that Kaplan–Meier estimator derived from the right endpoint of the current status data tends to overestimate recurrence rate in contrast to logistic regression and the weighted logistic regression method can produce reasonable estimates of recurrence rate even under a high non‐compliance rate compared to conventional logistic regression and Kaplan–Meier estimator. The method described here is illustrated with an example from a colon cancer study. Copyright © 2006 John Wiley & Sons, Ltd.
Review of the Pathophysiology and Management of Postoperative Ileus
Authors: Mattei Peter , Rombeau John L. 
Published: July 2006

AbstractInvestigations in the pathophysiology and treatment of postoperative ileus continue to evolve. Bowel rest is no longer a mandatory component of postoperative recovery. Tolerance of enteral nutrition and normalization of the abdominal examination are more accurate indications of the resolution of postoperative ileus than passage of flatus or first bowel movement. A multimodal "fast track" recovery approach incorporated into a clinical pathway provides a more rapid return of intestinal function and shortened hospital stay in patients undergoing major, uncomplicated gastrointestinal surgery.
New Type of Jejunal Interposition Method after Gastrectomy
Authors: Zherlov Georgy , Koshel Andrey , Orlova Yuliya , Zykov Dmitry , Sokolov Sergey , Rudaya Nataliya , Karpovitch Alexander 
Published: July 2006

AbstractBackground:Total and subtotal gastrectomies are methods of choice in surgical treatment of gastric cancer. These ablative operations eliminate the gastric reservoir and severely alter digestive physiology.Methods:We have created a unique method of reconstruction of “the jejunal pouch” following gastrectomy using the first loop of the jejunum together with the formation of antireflux anastomosis.Results:An analysis of the results of the application of a new way of reconstruction of the digestive path was carried out. Seventy‐five patients with gastric cancer received the new type of reconstruction. Among them, there were 52 men and 23 women aged 36–72 years. In the new interposition method group, in the first year after the surgical operation, the patients returned to 89.8% of their original body weight and in the second year to 89.7%; and in the Roux‐en‐Y group the patients returned to 64.4% and 59.2% of their body weight respectively. Further body weight fluctuations in patients after the new operative technique were determined by diet and aging and were not connected with digestive disorders. In the group receiving the new operative technique, the dumping syndrome was recorded in 4 (5.3%) patients and in the Roux‐en‐Y operation this syndrome occurred in 22 (27.5%) patients more than 1 year following the operations. There were no cases of reflux disease in the group undergoing the new operative technique. The average evacuation time of the “jejunal pouch” was 84 ± 9.8 min after the new operation and 57.5 ± 10.1 minutes after the Roux‐en‐Y operation.Conclusions:The comparative analysis of the results of the new operation (75 patients) with 80 patients (who were operated on using the traditional method) after the Roux‐en‐Y operation showed the significant advantages of the new method due to a diminished occurrence of troublesome gastrointestinal symptoms. We consider that the reconstruction of the gastrointestinal tract after total gastrectomy should give the maximal comfort for the rest of the patient’s life.