bluuebunny/crossref_metadata_2025 huggingface dataset:
Grid‐based metaheuristics to improve a nuclear fusion device
Authors: Gómez‐Iglesias Antonio , Vega‐Rodríguez Miguel A. , Castejón Francisco , Morales‐Ramos Enrique , Cárdenas‐Montes Miguel , Reynolds José M.
Published: September 2009

Plasma physics research for fusion still presents open problems that need a large computing capacity to be solved. Different modelling tools can be used to carry out simulations that will lead to saving costs in the development of fusion devices. The use of evolutionary algorithms (EAs) to look for approximate configurations offers a great approach for optimization processes, and avoids the use of brute force algorithms. However, since these applications require a high computational cost to perform their operations, the use of the grid arises as an ideal environment to carry out these tests. The distributed paradigm of the grid, as well as the number of computational resources, represents an excellent alternative to execute these tools. In this work we join these three ideas and present promising results. Copyright © 2009 John Wiley & Sons, Ltd.
The variational Kalman filter and an efficient implementation using limited memory BFGS
Authors: Auvinen H. , Bardsley J. M. , Haario H. , Kauranne T.
Published: September 2009

In the field of state space estimation and data assimilation, the Kalman filter (KF) and the extended Kalman filter (EKF) are among the most reliable methods used. However, KF and EKF require the storage of, and operations with, matrices of size n×n, where n is the size of the state space. Furthermore, both methods include inversion operations for m×m matrices, where m is the size of the observation space. Thus, KF methods become impractical as the dimension of the system increases. In this paper, we introduce a variational Kalman filter (VKF) method to provide a low storage, and computationally efficient, approximation of the KF and EKF methods. Furthermore, we introduce a variational Kalman smoother (VKS) method to approximate the fixed‐lag Kalman smoother (FLKS) method. Instead of using the KF formulae, we solve the underlying maximum a posteriori optimization problem using the limited memory Broyden–Fletcher–Goldfarb–Shanno (LBFGS) method. Moreover, the LBFGS optimization method is used to obtain a low storage approximation of state estimate covariances and prediction error covariances. A detailed description of the VKF and VKS methods with LBFGS is given. The methodology is tested on linear and nonlinear test examples. The simulated results of the VKF method are presented and compared with KF and EKF, respectively. The convergence of BFGS/LBFGS methods is tested and demonstrated numerically. Copyright © 2009 John Wiley & Sons, Ltd.
The cost‐effectiveness of a law banning the use of cellular phones by drivers
Authors: Sperber Daniel , Shiell Alan , Fyie Ken
Published: September 2009

Objective: To assess the cost‐effectiveness of a law banning the use of cellular phones by drivers in the Canadian province of Alberta.

Method: Cost‐effectiveness analysis using a probabilistic decision‐analytic model and publicly available data. We adopted a societal perspective. Health gains were measured in terms of quality‐adjusted life‐years. Costs include those associated with awareness raising, enforcement and the welfare loss associated with the reduction in cellular phone use, less savings in health care and other costs associated with automobile accidents.

Results: A ban promotes health and releases resources worth more than the costs. There is an 80% chance that a ban will be ‘cost saving’, and a 94% chance that a ban will cost less than Can$50 000/QALY. The results are sensitive to the additional risk posed by cellular phone use while driving, and the rate and pattern with which drivers comply with a ban.

Conclusion: Under our base line assumptions a cellular phone ban is likely to be cost saving from a societal perspective. The results are sensitive to parameters for which there is very little information or for which the available information is contradictory. Copyright © 2009 John Wiley & Sons, Ltd.
China's Enterprise Bankruptcy Law (EBL 2006): cross‐border perspectives
Authors: Bu Qingxiu
Published: September 2009

With China's new Enterprise Bankruptcy Law (‘EBL 2006’) having come into effect on 1 June 2007, a critical issue arises as to the extent to which Article 5, as a cross‐border provision, will strengthen creditors' rights across jurisdictions. In this paper attention will be paid in particular to how the Chinese People's Court is likely to exercise its discretion to grant recognition to a foreign court ruling, and vice versa. The paper will start with a brief introduction to the circumstances under which Article 5 came into being. The evolution of China's cross‐border insolvency practices will be examined through an analysis of an inbound case of B&T (2002) as well as an outbound one of GITIC (2005). In spite of the fact that China has not adopted the UNCITRAL Model Law, essential factors deemed necessary to be considered by China's court and its counterparts in US and UK are to be highlighted throughout the paper. Although the effect of Article 5 remains to be seen, it will be critically analysed focusing on some controversial issues. Copyright © 2009 John Wiley & Sons, Ltd.
Institutional researchers as change agents
Authors: Swing Randy L.
Published: September 2009

The future challenge and opportunity for institutional researchers is serving as change agents. This chapter offers suggestions for how institutional researchers can become change agents and issues calls to action from institutional research professional associations, graduate programs, and managers and practitioners.
Institutional researchers' expanding roles: Policy, planning, program evaluation, assessment, and new research methodologies
Authors: Delaney Anne Marie
Published: September 2009

This chapter explores how institutional researchers can enhance their value by expanding roles in policy, planning, evaluation and assessment, and by assuming new roles in program design and knowledge generation.
Laying the foundation: Institutional research office organization, staffing, and career development
Authors: Leimer Christina , Terkla Dawn Geronimo
Published: September 2009

Appropriate staffing is critical to effective institutional research, yet most institutional research offices are chronically understaffed. How many and what types of staffing are needed for the ideal institutional research office, and how can it be achieved?
Tertiary butyl alcohol in drinking water induces phase I and II liver enzymes with consequent effects on thyroid hormone homeostasis in the B6C3F1 female mouse
Authors: Blanck O. , Fowles J. , Schorsch F. , Pallen C. , Espinasse‐Lormeau H. , Schulte‐Koerne E. , Totis M. , Banton M.
Published: September 2009

Tertiary butyl alcohol (TBA) was administered to groups of 15 female B6C3F1 mice in drinking water at concentrations of 0, 2.0 or 20 mg TBA ml−1, for 14 days, for assessment of gross and histological changes in the liver and thyroid, thyroid hormones (T3, T4, and TSH), total hepatic cytochrome P450 (Cyp) content, specific Cyp activities and quantitative PCR analysis of specific Cyp enzymes (Cyp1a1, Cyp2b9, Cyp2b10, Cyp3a11), sulfuryltransferases (ST1a1, ST2a2, and STn) and glucuronyltransferases (UGT1a1, UGT2b1, and UGT2b5). Phenobarbital (PB) was administered to a positive control group by oral gavage at a daily dose of 80 mg kg−1. TBA caused, on day 14, a reduction in circulating T3 (12–15% decrease) and a dose‐dependent reduction in T4 (13–22% decrease), with no evidence of thyroid pathology. Two of five livers examined in the 20 mg TBA ml−1dose group showed mild, diffuse centrilobular hypertrophy. On day 14, Cyp 7‐benzoxyresorufin‐O‐debenzylase activity was significantly induced 12‐fold by TBA at 20 mg ml−1, and 1.8‐fold at the 2.0 mg TBA ml−1concentration. Cyp 7‐pentoxyresorufin‐O‐dealkylase activity was slightly induced (2.1‐fold) by 20 mg TBA ml−1on day 14. Quantitative PCR analysis of gene transcripts showed a significant induction of Cyp2b10 and ST1a1 with both TBA concentrations, and a slight induction of Cyp2b9 at 20 mg TBA ml−1only. PB induced all phase I and phase II gene transcripts except for Cyp1a1 and Cyp2b9. These findings suggest that TBA, at and below doses used in chronic studies, is an inducer of phase I and phase II liver enzymes, with resulting decreases in circulating thyroid hormones in B6C3F1 mice. Copyright © 2009 John Wiley & Sons, Ltd.
Sequencing analysis of mutations induced by N‐ethyl‐N‐nitrosourea at different sampling times in mouse bone marrow
Authors: Wang Jianyong , Chen Tao
Published: September 2009

In our previous study (Wang et al., 2004, Toxicol. Sci. 82: 124–128), we observed that the cII gene mutant frequency (MF) in the bone marrow of Big Blue mice showed significant increase as early as day 1, reached the maximum at day 3 and then decreased to a plateau by day 15 after a single dose of carcinogen N‐ethyl‐N‐nitrosourea (ENU) treatment, which is different from the longer mutation manifestation time and the constancy of MFs after reaching their maximum in some other tissues. To determine the mechanism underlying the quick increase in MF and the peak formation in the mutant manifestation, we examined the mutation frequencies and spectra of the ENU‐induced mutants collected from different sampling times in this study. The cII mutants from days 1, 3 and 120 after ENU treatment were randomly selected from different animals. The mutation frequencies were 33, 217, 305 and 144 × 10−6 for control, days 1, 3, and 120, respectively. The mutation spectra at days 1 and 3 were significantly different from that at day 120. Considering that stem cells are responsible for the ultimate MF plateau (day 120) and transit cells are accountable for the earlier MF induction (days 1 or 3) in mouse bone marrow, we conclude that transit cells are much more sensitive to mutation induction than stem cells in mouse bone marrow, which resulted in the specific mutation manifestation induced by ENU. Published in 2009 by John Wiley & Sons, Ltd.
Sieve‐based device for MALDI sample preparation. II. Instrumental parameterization
Authors: Cristoni Simone , Molin Laura , Crotti Sara , Rossi Bernardi Luigi , Seraglia Roberta , Traldi Pietro
Published: September 2009

A simple device effective for matrix‐assisted laser desorption/ionization (MALDI) sample preparation, based on the spraying of matrix/sample solution through a stainless steel sieve (sieve‐based device, SBD), has been employed for the preparation of MALDI samples of peptides, polysaccharides and high molecular weight proteins. The instrumental parameters, mainly the sprayer voltage, solution and auxiliary gas flows, and distances between sprayer–sieve and sieve–MALDI sample holder have been optimized. The MALDI spectra obtained by laser irradiation of the microspots so obtained, exhibit resolution and sensitivity higher than those achieved by the commonly employed dried droplets (DD) method. Worth noting is the fact that, in contrast to what is observed in the DD method, identical spectra are obtained by irradiation of different areas of the MALDI sample, showing that by using the SBD the matrix/analyte ratio is constant over the entire surface. Copyright © 2009 John Wiley & Sons, Ltd.
Location, location, location: changes in the diversity of animal resources exploited by Tardiglacial humans in northern Spain
Authors: Turrero Pablo , García‐Vázquez Eva , Arbizu Miguel , Adán Gema E.
Published: September 2009

Prey diversity of Homo sapiens in north Iberia exhibited shifts associated with climate warming after the Last Glacial Maximum, as deduced from animal remains obtained from Upper Palaeolithic caves in Asturias (northern Spain). Significant association of prey diversity and river proximity was found during adverse climate conditions, indicating opportunistic predation. A high increase of prey diversity was found when small animals (including fish) were taken into account in archaeological records, highlighting the importance of this type of prey in Palaeolithic diets. Copyright © 2009 John Wiley & Sons, Ltd.
Early Pleistocene evolution of the Japan Sea Intermediate Water
Authors: Kitamura Akihisa
Published: September 2009

The Early Pleistocene fossil record of the Japan Sea reveals that the planktonic foraminifer Globorotalia inflata succeeded in expanding its range from the East China Sea to the Japan Sea during interglacial stages of the Early Pleistocene; however, the species is only found in surface sediment samples from the southwestern‐most part of the sea. Based on the ecology of G. inflata and the water mass structure of the Japan Sea, it appears that its geographical distribution is mainly controlled by the low temperature of the intermediate water, which is caused by the cool‐water mass of Japan Sea Proper Water. The temporal and spatial patterns of G. inflata occurrence indicate that the intermediate water at 200 m depth during interglacial stages between 1.46 and 1.3 Ma was warmest during the Quaternary. This warm intermediate water probably resulted from the influence of the low‐salinity nature of the Tsushima Current due to the large inflow of East China Sea Coastal Water. After 1.3 Ma, the intermediate water at 200 m depth became cooler in a step‐wise manner. This cooling can be explained by an intensification of thermohaline circulation in the Japan Sea associated with strengthening of the East Asian winter monsoon and an increase in salinity due to enlargement of the southern strait. Copyright © 2009 John Wiley & Sons, Ltd.
Ionic liquid‐based ultrasound‐assisted extraction of fangchinoline and tetrandrine from Stephaniae tetrandrae
Authors: Zhang Lijin , Geng Yanling , Duan Wenjuan , Wang Daijie , Fu Maorun , Wang Xiao
Published: September 2009

An ionic liquid‐based ultrasound‐assisted extraction method has been developed for the effective extraction of fangchinoline and tetrandrine from Stephaniae tetrandrae. The effects of some ultrasound‐assisted extraction parameters including the concentration of [BMIM][BF4], pH, ultrasonic power and time were investigated to optimize the ultrasound‐assisted extraction conditions. Compared to the regular ultrasound‐assisted extraction and traditional refluent extraction, the proposed [BMIM][BF4]‐based ultrasound‐assisted extraction offered shorter extraction times (from 6 h to 40 min) and remarkable higher efficiencies (approximately 30% improved), which supported the suitability of the proposed approach. In addition, the proposed approach was confirmed by the good correlation coefficient (R2), recovery and reproducibility (RSD, n = 5), which were in the range of 0.9992–0.9995, 85.5–101.1%, and 1.87–4.33%, respectively.
The Ussing type chamber model to study the intestinal transport and modulation of specific tight‐junction genes using a colonic cell line
Authors: Bergmann Hannah , Rogoll Dorothee , Scheppach Wolfgang , Melcher Ralph , Richling Elke
Published: September 2009

Polyphenols in apples, such as various hydroxycinnamic acids and flavonoids, have positive health effects that strongly depend on their bioavailability. In order to show that the Ussing‐type chamber is a useful model to study metabolism, transport, and tightness of cell monolayers in one experimental setup, monolayers of the T84 colon carcinoma cell line mounted in Ussing‐type chambers were incubated in the presence of physiological concentrations of various hydroxycinnamic acids (including ferulic, isoferulic, cinnamic, and hydrocinnamic acids) and flavonoids for 4 h. Concentrations of each tested polyphenol in the apical chamber, basolateral chamber, and those associated with the cells were then determined using HPLC with DAD (HPLC‐DAD). The transport studies showed that the amounts of the tested polyphenols that passed from the apical to the basolateral side of the T84 monolayers depended on their polarity. Metabolites, such as glucuronides and sulfates of ferulic acid, were also detected at measurable levels by HPLC‐ESI‐MS/MS in the model system, but only when they were supplied at supra‐physiological concentrations (>100 μM). In addition, the transepithelial resistance (TER) of T84 monolayers was measured before and after the addition of polyphenols, with and without short‐term exposure to apical sodium caprate (C10), a tight junction (TJ) modulator. Exposure to C10 induced a decrease in TER that was reversible by incubation with polyphenols. However, no increase in paracellular permeability of tested polyphenols was observed after apical C10 exposure, so C10 did not promote fluxes of hydroxycinnamic acids across the monolayers. Further, real‐time PCR analysis of the T84 colon cell line showed that ferulic and isoferulic acids induced significant increases in expression of the TJ components zonula occludens‐1 (ZO‐1) and claudin‐4 transcription, but reductions in occludin expression. In contrast, caffeic andp‐coumaric acids had no significant effects on the transcription of either ZO‐1 or occludin. Our results provide confirmation that T84 cells could be used as model system to simulate the intestinal mucosa, and that polyphenols are able to increase the TER of C10‐treated and ‐untreated T84 monolayers.
The complex links between dietary phytochemicals and human health deciphered by metabolomics
Authors: Manach Claudine , Hubert Jane , Llorach Rafael , Scalbert Augustin
Published: September 2009

A large variety of phytochemicals commonly consumed with the human diet, influence health and may contribute to the prevention of diseases. However, it is still difficult to make nutritional recommendations for these bioactive compounds. Current studies of phytochemicals are generally focused on specific compounds and their effects on a limited number of markers. New approaches are needed to take into account both the diversity of phytochemicals found in the diet and the complexity of their biological effects. Recent progress in high‐throughput analytical technologies and in bioinformatics now allows the simultaneous analysis of the hundreds or more metabolites constituting the metabolome in urine or plasma. These analyses give complex metabolic fingerprints characteristic of a given phenotype. The exploitation of the wealth of information it contains, in randomized controlled trials and cohort studies, should lead to the discovery of new markers of intake for phytochemicals and new markers of effects. In this paper, we briefly review the current methods used to evaluate intake of phytochemicals and their effects on health. We then describe the applications of metabolomics in this field. Recent metabolomics studies illustrate the potential of such a global approach to explore the complex relationships linking phytochemical intake and metabolism and health.
Influence of boundary conditions, specimen geometry and material heterogeneity on model calibration from triaxial tests
Authors: Medina‐Cetina Zenon , Rechenmacher Amy
Published: September 2009

The recent capability of measuring full‐field deformations using advanced imaging techniques provides the opportunity to improve the predictive ability of computational soil mechanics. This paper investigates the effects of imperfect initial specimen geometry, platen‐soil and apparatus compliance, and material heterogeneity on the constitutive model calibration process from triaxial tests with nonlubricated platens. The technique of 3D‐Digital Image Correlation (3D‐DIC) was used to measure, from digital images, full‐field displacements over sand specimen surfaces throughout triaxial compression tests, as well as actual specimen initial shape, and deformations associated with platen and apparatus compliance and bedding settlement. The difference between predicted and observed 3D specimen surface deformations served to quantify an objective function in the optimization algorithm. Four different three‐dimensional finite element models (FEMs), each allowing varying degrees of material variability in the solution of the inverse problem, were used to study the effect of material heterogeneity. Results of the parametric study revealed that properly representing the actual initial specimen geometry significantly improves the optimization efficiency, and that accounting for boundary compliance can be critical for the accurate recovery of the full‐field experimental displacements. Allowing for nonsymmetric material variability had the most significant impact on predicted behavior. A relatively high coefficient of variation in model parameters was found among a statistical ensemble of tests, underscoring the importance of conducting multiple tests for proper material characterization. Copyright © 2009 John Wiley & Sons, Ltd.
Seladin‐1 and testicular germ cell tumours: new insights into cisplatin responsiveness
Authors: Nuti Francesca , Luciani Paola , Marinari Eliana , Erdei Edit , Bak Mihaly , Deledda Cristiana , Rosati Fabiana , Mazzinghi Benedetta , Danza Giovanna , Stoop Hans , Looijenga Leendert HJ , Peri Alessandro , Serio Mario , Krausz Csilla
Published: September 2009

The molecular basis for the exquisite sensitivity of testicular germ cell tumours of adolescents and adults (TGCTs), ie seminomas and non‐seminomatous germ cell tumours, to chemo/radiotherapy has not been fully clarified so far. It has been suggested that it may be dependent on factors involved in the regulation of apoptosis. Seladin‐1 is a multi‐functional protein involved in various biological processes, including apoptosis. The aim of our study was to assess the expression of seladin‐1 in different histological types of TGCTs, known to have varying treatment sensitivity, in order to establish whether this protein may influence cisplatin responsiveness in vitro. Seladin‐1 expression levels, both at the mRNA and at the protein level, were higher in the adjacent normal parenchyma than in the pathological counterparts. In tumoural tissues, the level of expression differed among TGCT histological types. The highest tumour‐expression level was found in teratoma, whereas the lowest was detected in seminoma, corresponding to the different chemo/and radiosensitivities of these tumour types. In common with other cancers, in TGCT‐derived cell lines seladin‐1 showed anti‐apoptotic properties through inhibition of caspase‐3 activation. We confirmed our results using a non‐seminomatous cell line model (NT2) before and after differentiation with retinoic acid. Significantly higher seladin‐1 expression was observed in the differentiated derivatives (teratoma) and an inverse relationship was found between seladin‐1 expression and the amount of cleaved caspase‐3. Seladin‐1 silencing or overexpression in this cell line supports involvement of seladin‐1 in cisplatin responsiveness. Seladin‐1 silencing was associated with greater cisplatin responsiveness demonstrated by decreased cell viability and increased expression of apoptotic markers. In contrast, overexpression of seladin‐1 was associated with a higher survival rate and a clear anti‐apoptotic effect. In conclusion, we have demonstrated for the first time an important role for seladin‐1 in the biology of TGCTs and provided new insights into cisplatin responsiveness of these tumours. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The Li–Fraumeni syndrome (LFS): a model for the initiation of p53 signatures in the distal Fallopian tube
Authors: Xian Wa , Miron Alexander , Roh Michael , Semmel Dana R , Yassin Yosuf , Garber Judy , Oliva Esther , Goodman Annekathryn , Mehra Karishma , Berkowitz Ross S , Crum Christopher P , Quade Bradley J
Published: September 2009

A candidate early precursor to pelvic serous cancer, the ‘p53 signature’, is commonly found in the benign mucosa of the distal Fallopian tube and harbours p53 mutations and evidence of DNA damage. We examined tubes from women with pre‐existing (germ‐line) mutations in p53 [Li–Fraumeni syndrome (LFS)] for evidence of this precursor. Fallopian tubes from two cases of LFS were immunostained for p53, Ki‐67 (proliferation) and H2AX (DNA damage response) and analysed for p53 mutations by laser capture microdissection (LCM) and p53 genomic sequencing (exons 2–11). A common single nucleotide repeat (snp) in exon 3 (rs1042522) and deletion sequencing chromatograms in exon 4 were examined in combination to estimate LOH in both LFS tubes and advanced serous carcinomas from the general population. LFS tubal epithelium contained abundant (10–20 per section) p53 signatures with evidence of DNA damage and low proliferative activity. Six of 11 LFS microdissected p53 signatures (55%) and 15 of 21 serous carcinomas (71%) revealed LOH at the p53 locus, relative to background epithelium. The LFS model confirms prior observations that the distal Fallopian tube is particularly prone to focal epithelial p53 gene inactivation—p53 mutation and LOH—in the absence of malignancy or increased epithelial proliferation. The fact that the LFS is not associated with ovarian cancers is consistent with the concept that loss of p53 function must be accompanied by at least one more genotoxic event (including BRCA1/2 functional inactivation) to produce the malignant phenotype. This is in keeping with a general model of carcinogenesis, in which different and often independent risk factors operate at multiple points in the serous carcinogenic spectrum. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Impact of VEGF‐dependent tumour micro‐environment on EDB fibronectin expression by subcutaneous human tumour xenografts in nude mice
Authors: Coltrini Daniela , Ronca Roberto , Belleri Mirella , Zardi Luciano , Indraccolo Stefano , Scarlato Valentina , Giavazzi Raffaella , Presta Marco
Published: September 2009

Fibronectin (FN) is an extracellular matrix cell‐adhesive glycoprotein. The alternative spliced isoform EDB‐FN (extra domain B containing FN) is highly expressed in tumour blood vessels and stroma and represents a candidate for tumour targeting. To investigate the impact of different angiogenic micro‐environments on EDB‐FN expression, we used a tumour model in which human endometrial adenocarcinoma Tet‐FGF2 cells overexpressing fibroblast growth factor‐2 (FGF2) driven by the tetracycline‐responsive promoter were further transfected with a VEGF antisense cDNA, generating AS‐VEGF/Tet‐FGF2 cells. In this model, the expression of FGF2 plus VEGF results in fast‐growing, highly vascularized Tet‐FGF2 tumours. Down‐regulation of FGF2 production by tetracycline administration and/or of VEGF production by AS‐VEGF transduction inhibited tumour growth and vascularization, with profound changes in tumour micro‐environment. Quantitative RT‐PCR analysis using human EDB‐FN primers shows that subcutaneous grafting in immunodeficient mice is per se sufficient to cause a dramatic up‐regulation of EDB‐FN expression by these cells, as well as by human oesophageal cancer KYSE 30 cells and renal carcinoma Caki‐1 cells. However, in vivo down‐regulation of VEGF expression, as occurs in AS‐VEGF/Tet‐FGF2 tumours, and to a lesser extent of FGF2 expression, as occurs in tetracycline‐treated Tet‐FGF2 tumour‐bearing animals, causes significant inhibition of EDB‐FN production in tumour grafts, as shown by immunohistochemistry and quantitative RT‐PCR analysis. Accordingly, treatment of Tet‐FGF2 tumour‐bearing animals with the neutralizing anti‐murine VEGF receptor‐2 antibody DC101, or of Caki‐1 tumour‐bearing animals with the anti‐VEGF antibody bevacizumab, inhibited EDB‐FN expression in tumour grafts. EDB‐FN down‐regulation was paralleled by a decrease in vascularity, thus confirming EDB‐FN as a marker of tumour angiogenesis. These data demonstrate that the angiogenic micro‐environment, and in particular the VEGF/VEGFR‐2 system, plays a key role in modulating EDB‐FN expression by tumour cells in vivo. This may have implications for the design of therapeutic strategies targeting EDB‐FN in combination with anti‐angiogenic and/or cytotoxic drugs. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Rheological behavior of polydispersed bubble suspensions in shear flows
Authors: Joh Sung Wu , Lee Seung Hwan , Youn Jae Ryoun
Published: September 2009

Effects of the capillary number and size distribution of bubbles on rheological properties of bubble suspensions with different volume fractions were investigated through both experimental and theoretical analyses. Polydispersed bubble suspensions were prepared by using a bubble making device and characterized in steady and dynamic oscillatory shear flows to examine the effect of the bubble size distribution. To predict the rheological properties of the polydispersed bubble suspension, a constitutive equation was modified by applying superposition schemes, i.e., a probability density function was introduced to reflect the size distribution of bubbles. Dilute bubble suspensions showed shear thinning and linear viscoelastic behavior. At small capillary numbers, relative viscosity increased with increasing bubble volume fraction, whereas it decreased as bubble volume fraction increased at relatively large capillary numbers. It was found that rheological properties had been affected significantly by polydispersity of bubble suspensions and theoretical results were in good agreement with the experimental results. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Better characterization of raw natural rubber by decreasing the rotor speed of Mooney viscometer: Role of macromolecular structure
Authors: Kim Chandy , Morel Marie‐Hélène , Beuve Jérôme Sainte , Guilbert Stéphane , Bonfils Frédéric
Published: September 2009

The objective of our work was to characterize natural rubber (NR) samples with different macromolecular structures by measuring Mooney viscosities (VR) at variable rotor speeds ≤2 rpm, called variable speed Mooney viscosity (MVS). Model samples of technically specified rubbers of constant Mooney viscosity (TSR5CV) were prepared with chosen specific clones. The structures of the samples were characterized by size‐exclusion chromatography coupled with an online multi‐angle light‐scattering detector (SEC‐MALS). Rheological properties of the samples were also characterized by a dynamic moving die rheometer. Measuring monoclonal model samples by MVS showed three types of VR flow curves. The VR at high rotor speed (2 rpm) was correlated with number‐average molar mass (Mn), whereas VR at low rotor speed (0.05 rpm) was correlated with weight‐average molar mass (Mw). Measuring MVS revealed the rheological behaviors of samples and enabled discrimination between samples with different macromolecular structures and should thus help in predicting processability. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Multi‐jet ejection and fluctuation in electrospinning of polyvinyl alcohol with various nozzle diameters
Authors: Kong Chang Suk , Lee Seung Goo , Lee Sung Hoon , Lee Kyung Hwa , Jo Na Gyeong , Kim Han Seong
Published: September 2009

This article has been retracted due to dual submission and publication.
A study on the optical properties of three‐armed polystyrene and poly(styrene‐b‐isobutyl methacrylate)
Authors: Kurt Adnan , Demirelli Kadir
Published: September 2009

Atom transfer radical polymerization (ATRP) of three‐armed polystyrene[PS] and poly(styrene‐b‐isobutyl methacrylate)[PS‐b‐PiBμMA] were accomplished using an initiator with tri‐active C‐Br end group function and cuprous (I) bromide/2,2′‐bipyridyne catalytic system. The characterization obtained by FT‐IR, 1H‐NMR, and GPC techniques. The average molecular weight and polydispersity of PS and PS‐b‐PiBμMA were determined as 19,800, 29,300 and as 1.37 and 1.15, respectively, which indicates that the constant concentration of growing chains are present throughout the polymerization. The refractive index and extinction coefficient of the samples were determined in the visible range as a function of wavelength. The refractive index dispersion curves of the thin films were fitted by the Cauchy‐Sellmeier model. The width of localized states (Eu) values changed inversely with optical band gaps (Eg) of the films. While the calculated Eu values of films for initiator, PS and PS‐b‐PiBμMA were determined as 2.72, 2.98, and 2.94 eV, the Eg values were determined as 3.43; 3.11, and 3.16 eV, respectively. The dispersion parameters of thin films were determined. These parameters changed in the investigated wavelength ranges. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Impression creep of PMR‐15 resin at elevated temperatures
Authors: Chen Rong , Lu Y.C. , Yang Fuqian , Tandon G.P. , Schoeppner G.A.
Published: September 2009

The polyimides formed from the polymerization of monomeric‐reactants (PMR) approach have been increasingly used as matrix materials in fiber‐reinforced composites on aerospace and space structures for high temperature applications. The performance of PMR‐based structures depends on the mechanical durability of PMR resins at elevated temperatures, including creep and stress relaxation. In this work, the creep behavior of PMR‐15 resin was studied using the impression technique in the temperature range of 563–613 K and the punching stress range of 76–381 MPa. It was found that there existed a steady state creep for the creep tests performed at temperatures of 563 K and higher, from which a constant impression velocity was calculated. The steady state impression velocity increased with temperature and punching stress with the stress exponent in the range of 1.5–2.2. The average of the apparent activation energy of the PMR‐15 was calculated as 122.7 ± 6.1 kJ/mol. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Cavitation in unfilled and nano‐CACO3 filled HDPE subjected to tensile test: Revelation, localization, and quantification
Authors: Addiego Frédéric , Di Martino Jean , Ruch David , Dahoun Abdesselam , Godard Olivier , Lipnik Pascale , Biebuyck Jean‐Jacques
Published: September 2009

This paper is focused on the quantitative characterization of cavitation developing in unfilled and nano‐CaCO3 filled high density polyethylene (HDPE) subjected to tensile test. In particular, a methodology to reveal the voids, take into account their localization, and evaluate their characteristics (density and shape), is presented. For this, post‐mortem investigations coupling a cryosectioning method and a pressure‐controlled scanning electron microscope (PC‐SEM) were conducted. In the two materials, whatever the active cavitation mechanism (crazing in neat HDPE or debonding in CaCO3/HDPE system), it was shown that the cavity density and the cavity height/width ratio (shape factor) increase with the deformation state. These two parameters are also influenced by the macroscopic stress triaxiality generated by the necking process. Indeed, when the intensity of the triaxiality is high, the cavity density and the cavity shape factor significantly increase from the skin to the core of the specimen. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Melt viscoelastic properties of peroxide cured polypropylene‐ethylene octene copolymer thermoplastic vulcanizates
Authors: Babu R. Rajesh , Singha Nikhil K. , Naskar Kinsuk
Published: September 2009

The dynamic viscoelastic properties of uncrosslinked and dynamically crosslinked blends of polypropylene (PP) and ethylene octene copolymer (EOC) were investigated in the melt state to study the mechanism of reinforcement, influence of particle size, and kinetics of modulus recovery. Dynamic vulcanization was performed by coagent assisted peroxide crosslinking system. Addition of peroxide in PP/EOC blend involves two major competing reactions: crosslinking in EOC and degradation of PP by β chain‐scission. In this article, morphological and melt rheological properties of the TPVs were studied with special reference to the effect of mixing protocol. Three different mixing techniques were investigated. They are: (i) conventional or preblending method—melt mixing of PP and EOC followed by dynamic vulcanization (ii) phase mixing method—curative master batch of EOC added on the molten PP (iii) split addition of PP—preblending method followed by addition of half part of PP (dilution procedure). The type of mixing protocol has a significant influence on the rheological behavior. Rheological properties have been evaluated at the processing temperature (180°C) in a Rubber Process Analyzer (RPA 2000). A variety of rheological observations such as Payne effect, modulus recovery and shear rate sensitivity were studied by carrying out frequency and strain amplitude sweeps. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Interactive functional poly(vinylidene fluoride) membranes with modulated lysozyme affinity: a promising class of new interfaces for contactor crystallizers
Authors: Gugliuzza Annarosa , Aceto Marianna C , Drioli Enrico
Published: September 2009

BACKGROUND: One of the challenges of current researches in biotechnological fields is the achievement of regular and increasingly smaller protein crystals for genomics and biocatalyst applications. The membrane contactor‐based methodology appears to be a time‐effective and economically competitive technology for accomplishing this target.

RESULTS: A new class of interactive polymeric interfaces enabling the nucleation of very small protein crystals in a short time through controlling attractive interactions is discussed. Specifically, the role of attractive interfacial forces between a model lysozyme solution and modified poly(vinylidene fluoride) membranes is examined. The insertion of amphiphilic motifs in the fluorinated membranes allows quicker agglomeration of protein crystals at the membrane surface reducing significantly the induction time for protein nucleation. The chemical nature of the modifier permits the modulation of the membrane affinity to the lysozyme, involving polar and non‐polar attractive interactions and preserving intrinsic structural features, transport properties and the hydrophobic character of the interfaces, according to the basics of membrane crystallization technology. The formation of critical nuclei is observed after 3 h and micro‐sized crystals are formed in less than 24 h.

CONCLUSION: The experimental evidence suggests these membranes as a promising class of interactive interfaces that may rapidly bring advances in genomics research. Copyright © 2009 Society of Chemical Industry
Proteomic analysis of sera of asymptomatic, early‐stage patients with Wilson's disease
Authors: Park Jung‐Young , Mun Joo Hee , Lee Beom Hee , Heo Sun Hee , Kim Gu‐Hwan , Yoo Han‐Wook
Published: September 2009

Wilson's disease (WD) is characterized by excessive accumulation of intracellular copper in liver and extrahepatic tissues, leading to significant oxidative stress and tissue damage. To date, several diagnostic biomarkers for WD such as serum ceruloplasmin, serum or urine copper levels and copper content in liver have been identified. However, these biomarkers may not be convincing for the diagnosis in some WD patients. To identify additional novel diagnostic biomarkers, we compared the serum protein profiles of asymptomatic childhood WD patients (n=20), without neurologic manifestation or liver cirrhosis, with normal controls (n=13). Fourteen spots, five up‐regulated and nine down‐regulated (>2‐fold), were differentially expressed in WD patients in comparison to normal control on 2‐DE. Among them, three spots were down‐regulated in both male and female WD. MS/MS analysis revealed that the three spots were complement component C3, complement factor B and alpha‐2 macroglobulin. By comparative proteome analysis, complement component C3, complement factor B and alpha‐2 macroglobulin, which are related to oxidative stress and inflammation, turned out to be good candidates for novel diagnostic biomarkers for early stages of WD.
How to maximize the capacity of general quantum noisy channels
Authors: Gordon G. , Kurizki G.
Published: September 2009

A general quantum noisy channel is analyzed, wherein the transmitted qubits may experience symmetry‐breaking decoherence, along with memory effects. We examine generalized Bell‐basis and find that the optimal basis is not the fully entangled one, but a combination of factorized and partially‐entangled states in the presence of memory, asymmetry and the state‐bias of the noise. Capacity‐maximization is shown to be achievable by combining temporal shaping of the transmitted qubits and optimal basis selection.
Solid‐state NMR and simulation studies of equinatoxin II N‐terminus interaction with lipid bilayers
Authors: Lam Yuen Han , Hung Andrew , Norton Raymond S. , Separovic Frances , Watts Anthony
Published: September 2009

The interaction with model membranes of a peptide, EqtII1–32, corresponding to the N‐terminal region of the pore‐forming toxin equinatoxin II (EqtII) has been studied using solid‐state NMR and molecular dynamics (MD) simulations. The distances between specifically labeled nuclei in [19F‐para]Phe16‐[1‐13C]Leu19 and [19F‐para]Phe16‐[15N]Leu23 analogs of EqtII1–32 measured by REDOR in lyophilized peptide were in agreement with published crystal and solution structures. However, in both DMPC and mixed DMPC:SM membrane environments, significant changes in the distances between the labeled amino acid pairs were observed, suggesting changes in helical content around the experimentally studied region, 16–23, in the presence of bilayers. 19F‐31P REDOR experiments indicated that the aromatic ring of Phe16 is in contact with lipid headgroups in both membrane environments. For the DMPC:SM mixed bilayers, a closer interaction between Phe16 side chains and lipid headgroups was observed, but an increase in distances was observed for both labeled amino acid pairs compared with those measured for EqtII1–32 in pure DMPC bilayers. The observed differences between DMPC and DMPC:SM bilayers may be due to the greater affinity of EqtII for the latter. MD simulations of EqtII1–32 in water, on a pure DMPC bilayer, and on a mixed DMPC:SM bilayer indicate significant peptide secondary structural differences in the different environments, with the DMPC‐bound peptide adopting helical formations at residues 16–24, whereas the DMPC:SM‐bound peptide exhibits a longer helical stretch, which may contribute to its enhanced activity against PC:SM compared with pure PC bilayers. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Binding of nitrogen‐containing bisphosphonates (N‐BPs) to the Trypanosoma cruzi farnesyl diphosphate synthase homodimer
Authors: Huang Chuan‐Hsiang , Gabelli Sandra B. , Oldfield Eric , Amzel L. Mario
Published: September 2009

Bisphosphonates (BPs) are a class of compounds that have been used extensively in the treatment of osteoporosis and malignancy‐related hypercalcemia. Some of these compounds act through inhibition of farnesyl diphosphate synthase (FPPS), a key enzyme in the synthesis of isoprenoids. Recently, nitrogen‐containing bisphosphonates (N‐BPs) used in bone resorption therapy have been shown to be active against Trypanosoma cruzi, the parasite that causes American trypanosomiasis (Chagas disease), suggesting that they may be used as anti‐trypanosomal agents. The crystal structures of TcFPPS in complex with substrate (isopentenyl diphosphate, IPP) and five N‐BP inhibitors show that the C‐1 hydroxyl and the nitrogen‐containing groups of the inhibitors alter the binding of IPP and the conformation of two TcFPPS residues, Tyr94 and Gln167. Isothermal titration calorimetry experiments suggest that binding of the first N‐BPs to the homodimeric TcFPPS changes the binding properties of the second site. This mechanism of binding of N‐BPs to TcFPPS is different to that reported for the binding of the same compounds to human FPPS. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Photoluminescence dynamics of AlGaN quantum wells with built‐in electric fields and localized states
Authors: Mickevičius J. , Kuokštis E. , Liuolia V. , Tamulaitis G. , Shur M. S. , Yang J. , Gaska R.
Published: September 2009

We report on photoluminescence (PL) studies of AlGaN/AlGaN multiple quantum well (MQW) structures with well widths spanning from 1.65 to 5.0 nm under various excitations and temperatures. The samples were fabricated by migration‐enhanced metal‐organic chemical vapor deposition technique (MEMOCVD®). Screening of the built‐in electric field by photogenerated carriers reduced quantum‐confined Stark effect (QCSE). This is confirmed by solving the Poisson and Schrodinger equations for AlGaN‐based quantum wells (QWs) under study. Analysis of the PL internal quantum efficiency under different excitations in MQWs with different widths shows strong influence of the carrier localization on the radiative properties of MQWs.
Study of the influence of the Cd:Se precursor ratio during the synthesis of CdSe nanocrystals on the performance of CdSe/P3HT hybrid solar cells
Authors: Zutz Folker , Lokteva Irina , Radychev Nikolay , Kolny‐Olesiak Joanna , Riedel Ingo , Borchert Holger , Parisi Jürgen
Published: September 2009

The influence of the Cd‐to‐Se precursor ratio during the synthesis of CdSe nanoparticles (nc‐CdSe) on the efficiency of solar cells made from semiconducting polymer/nanocrystal‐blends (hybrid solar cells) was investigated. In these hybrid solar cells regioregular poly‐(3‐hexylthiophene 2,5 diyl) (P3HT) was used as the electron donor material while the acceptor was established by CdSe nanocrystals prepared via colloidal synthesis. Furthermore, the influence of the nc‐CdSe‐to‐P3HT ratio in the semiconductor blend on the solar cell efficiency was investigated. CdSe:P3HT ratios of 8:1 to 10:1 were found to give the best results concerning the overall device performance as derived from current–voltage characterization. These findings were correlated with structural investigations of the active layer by means of atomic force microscopy (tapping mode AFM). Furthermore, the external quantum efficiency (EQE) of the hybrid solar cells was determined and also used to estimate the short circuit current density Jsc under standardized solar irradiation. The Jsc values from the EQE measurements were compared to the values obtained from the IV curves. Differences in these values could be explained by an intensity‐dependent influence of trap states.
Electron‐induced dissociation of doubly protonated betaine clusters: controlling fragmentation chemistry through electron energy
Authors: Feketeová Linda , O'Hair Richard A. J.
Published: September 2009

The [M21+2H]2+ cluster of the zwitterion betaine, M = (CH3)3NCH2CO2, formed via electrospray ionisation (ESI), has been allowed to interact with electrons with energies ranging from >0 to 50 eV in a Fourier transform ion cyclotron resonance (FT‐ICR) mass spectrometer. The types of gas‐phase electron‐induced dissociation (EID) reactions observed are dependent on the energy of the electrons. In the low‐energy region up to 10 eV, electrons are mainly captured, forming the charge‐reduced species, {[M21+2H]+.}*, in an excited state, which stabilises via the ejection of an H atom and one or more neutral betaines. In the higher energy region, above 12 eV, a Coulomb explosion of the multiply charged clusters is observed in highly asymmetric fission with singly charged fragments carrying away more than 70% of the parent mass. Neutral betaine evaporation is also observed in this energy region. In addition, a series of singly charged fragments appears which arise from CX bond cleavage reactions, including decarboxylation and CH3 group transfer. These latter reactions may arise from access of electronic excited states of the precursor ions. Copyright © 2009 John Wiley & Sons, Ltd.