bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pressure‐induced polymerization of tetraethylene glycol dimethacrylate
Authors: Kaminski Kamil , Paluch Marian , Wrzalik R. , Ziolo Jerzy , Bogoslovov Radoslav , Michael Roland C. 
Published: April 2008

AbstractThe polymerization and crosslinking of tetraethylene glycol dimethacrylate were induced by high pressure. The product was analyzed by both swelling experiments and broadband dielectric spectroscopy to determine the structure, with IR measurements used to follow the extent of reaction and its temperature dependence. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3795–3801, 2008
Dispersion copolymerization of 2‐ethylhexyl methacrylate and vinylbenzyl chloride and functional group conversions in a fluorinated solvent using microwave heating
Authors: Karnati Rangarani , Ford Warren T. 
Published: April 2008

AbstractConventional and microwave heating were compared for free radical dispersion polymerizations of crosslinked copolymers of 2‐ethylhexyl methacrylate, vinylbenzyl chloride (VBC), and fluoroalkyl methacryate monomers in the solvent nonafluorobutyl ethyl ether, and for the functional conversion of the VBC units of the copolymer particles with trimethylamine to quaternary ammonium chloride units. By conventional heating, all polymerizations produced foamy coagulated products consisting of primary spherical particles 1–2 μm in diameter. Microwave heating using poly(1H,1H‐dihydroperfluorooctyl acrylate) as a stabilizer gave faster polymerization and stable dispersions of discrete 1 μm particles. Microwave heating also gave faster reactions of the copolymers with trimethylamine to produce quaternary ammonium chloride functionalized colloidal particles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3813–3819, 2008
Synthesis of a new zirconium catalyst for ethylene polymerization
Authors: Fim Fabiana De C. , Machado Tiago , De Sá Denise Santos , Livotto Paolo R. , Da Rocha Zênis N. , Basso Nara R. De S. , Galland Griselda Barrera 
Published: April 2008

AbstractA novel complex dichlorobis(2‐ethyl‐3‐hydroxy‐4‐pyrone)zirconium(IV) (ZrCl2(ethylpyrone)2) was synthesized. Complexation of the pyrone ligand to the zirconium was confirmed by UV, 1H and 13C‐NMR, and electrochemical studies. NMR showed the presence of four isomers and density functional theory calculations indicated that the main isomer had a cis configuration. The catalyst was shown to be active in ethylene polymerization in the presence of the cocatalyst methylaluminoxane. The highest catalyst activity for the zirconium complex was achieved at Al/Zr = 2500, 70 °C and when a small concentration of catalyst was used (1 μmol). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3830–3841, 2008
Polyion complex micelles formed from glucose oxidase and comb‐type polyelectrolyte with poly(ethylene glycol) grafts
Authors: Kawamura Akifumi , Kojima Chie , Iijima Michihiro , Harada Atsushi , Kono Kenji 
Published: April 2008

AbstractThe comb‐type polyelectrolyte, poly(ethylene glycol)‐graft‐poly(allyl amine) (PEG‐g‐PAA), was synthesized to prepare polyion complex (PIC) micelles with Aspergillus Niger Glucose oxidase (GOD). Even after mixing GOD and PEG‐g‐PAAs with various PEG contents, the resulting mixtures remained transparent but the mixture of GOD and PAA homopolymer immediately precipitated. In the mixtures prepared with a stoichiometric mixing ratio, the formation of PIC micelles with a core‐shell structure was suggested from dynamic and static light scattering measurements. Glucose, the substrate for GOD, could easily diffuse into the PIC micelles, and the GOD molecules were active even in the core of the PIC micelles. GOD didn't lose its enzymatic activity through entrapment into the PIC micelles. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3842–3852, 2008
The effect of proton irradiation on the melting and isothermal crystallization of poly(ether‐ether‐ketone)
Authors: Al Lafi Abdul G. , Hay James N. , Parker David J. 
Published: April 2008

AbstractAmorphous poly(ether‐ether‐ketone) (PEEK) progressively crosslinks on irradiation with 11.0 MeV protons, and this has a marked effect on the extent of crystallinity that subsequently develops and on the kinetics of the high temperature isothermal crystallization. The extent of crystallinity with time was analyzed using the Avrami equation, and the temperature dependence of the rate constants was analyzed in terms of nucleation theory. While irradiation inhibits the overall rates of crystallization by the reduction in the mobility of the chain segments as observed by the progressive increase in the glass transition temperature, it also alters the fold surface free energy. The observed melting points were consistent with depression of the equilibrium melting point by the crosslinks produced by irradiation. These two effects alone are sufficient to account for the inhibition of crystallization on irradiation of PEEK by protons. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1094–1103, 2008
SFCscore: Scoring functions for affinity prediction of protein–ligand complexes
Authors: Sotriffer Christoph A. , Sanschagrin Paul , Matter Hans , Klebe Gerhard 
Published: April 2008

AbstractEmpirical scoring functions to calculate binding affinities of protein–ligand complexes have been calibrated based on experimental structure and affinity data collected from public and industrial sources. Public data were taken from the AffinDB database, whereas access to industrial data was gained through the Scoring Function Consortium (SFC), a collaborative effort with various pharmaceutical companies and the Cambridge Crystallographic Data Center. More than 850 complexes were obtained by the data collection procedure and subsequently used to setup different training sets for the parameterization of new scoring functions. Over 60 different descriptors were evaluated for all complexes, including terms accounting for interactions with and among aromatic ring systems as well as many surface‐dependent terms. After exploratory correlation and regression analyses, stepwise variable selection procedures and systematic searches, the most suitable descriptors were chosen as variables to calibrate regression functions by means of multiple linear regression or partial least squares analysis. Eight different functions are presented herein. Cross‐validated r2 (Q2) values of up to 0.72 and standard errors (sPRESS) generally below 1.15 pKi units suggest highly predictive functions. Extensive unbiased validation was carried out by testing the functions on large data sets from the PDBbind database as used by Wang et al. (J Chem Inf Comput Sci 2004;44:2114–2125) in a comparative analysis of other scoring functions. Superior performance of the SFCscore functions is observed in many cases, but the results also illustrate the need for further improvements. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Structures of a potent phenylalkyl bisphosphonate inhibitor bound to farnesyl and geranylgeranyl diphosphate synthases
Authors: Cao Rong , Chen Cammy K.‐M. , Guo Rey‐Ting , Wang Andrew H.‐J. , Oldfield Eric 
Published: April 2008

AbstractWe report the X‐ray crystallographic structures of the bisphosphonateN‐[methyl(4‐phenylbutyl)]‐3‐aminopropyl‐1‐hydroxy‐1,1‐bisphosphonate (BPH‐210), a potent analog of pamidronate (Aredia), bound to farnesyl diphosphate synthase (FPPS) fromTrypanosoma bruceias well as to geranylgeranyl diphosphate synthase fromSaccharomyces cerevisiae. BPH‐210 binds to FPPS, together with 3 Mg2+, with its long, hydrophobic phenylbutyl side‐chain being located in the same binding pocket that is occupied by allylic diphosphates and other bisphosphonates. Binding is overwhelmingly entropy driven, as determined by isothermal titration calorimetry. The structure is of interest since it explains the lack of potency of longer chain analogs against FPPS, since these would be expected to have a steric clash with an aromatic ring at the distal end of the binding site. Unlike shorter chain FPPS inhibitors, such as pamidronate, BPH‐210 is also found to be a potent inhibitor of human geranylgeranyl diphosphate synthase. In this case, the bisphosphonate binds only to the GGPP product inhibitory site, with only 1 (chain A) or 0 (chain B) Mg2+, and ΔSis much smaller and ΔHis ∼6 k cal more negative than in the case of FPPS binding. Overall, these results are of general interest since they show that some bisphosphonates can bind to more than onetrans‐prenyl synthase enzyme which, in some cases, can be expected to enhance their overall activityin vitroandin vivo. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Selection of global Metarhizium isolates for the control of the rice pest Nilaparvata lugens (Homoptera: Delphacidae)
Authors: Jin Shao‐Feng , Feng Ming‐Guang , Chen Jue‐Qi 
Published: April 2008

AbstractBACKGROUND: This study was initiated to search for fungal candidates for microbial control of brown planthopper (BPH) Nilaparvata lugens Stål, to which little attention has been paid in the past two decades.RESULTS: Thirty‐five isolates of Metarhizium anisopliae (Metschnikoff) Sorokin and M. flavoviride Gams & Rozsypal from different host insects worldwide were bioassayed for their lethal effects against third‐instar BPH nymphs at 25 °C and a 14:10 h light:dark photoperiod at ca 1000 conidia mm−2. On day 9 post‐treatment, mortality attributable to mycosis ranged from 6.5 to 64.2% and differed significantly among the tested isolates with no apparent relationship to their host origin. Only two BPH‐derived M. anisopliae isolates from the Philippines (ARSEF456) and Indonesia (ARSEF576) killed > 50% of the nymphs. Both isolates were further bioassayed for time–concentration–mortality responses of the nymphs to the sprays of 19–29, 118–164 and 978–1088 conidia mm−2 in repeated bioassays. The resultant data fitted a time–concentration–mortality model very well. Their LC50 values were estimated as 731 and 1124 conidia mm−2 on day 7 and fell to 284 and 306 conidia mm−2, respectively, on day 10.CONCLUSION: The two M. anisopliae isolates are potential biocontrol agents of BPH for further research. This is the first report of the lethal effects of global Metarhizium isolates on the rice pest. Copyright © 2008 Society of Chemical Industry
Atrial fibrillation: current approaches to drug therapy
Authors: Taggar Jaspal , Lip Gregory 
Published: April 2008

AbstractEffective treatment of atrial fibrillation is now a realistic goal as a result of recent advances in drug therapy. Our Drug review considers the properties of the drugs now available to achieve rhythm and rate control and prevent thromboembolism, followed by sources of further information and the Datafile. Copyright © 2008 Wiley Interface Ltd
Over‐the‐counter EHC: no substitute for family planning skills
Authors: Watkins Jean 
Published: April 2008

AbstractSince 2000, the ‘morningafter pill’ can be sold over the counter by trained pharmacists as part of a Government initiative to curb abortion and teenage pregnancy rates. Dr Jean Watkins argues that this is no substitute for consultation with a family planning specialist. Copyright © 2008 Wiley Interface Ltd
Preface: phys. stat. sol. (b) 245/5
Authors: Hettler Matthias H. , Lennartz Christian , Pflaum Jens 
Published: April 2008

AbstractOrganic materials exhibit fascinating transport phenomena at various length scales. For instance, macroscopic organic single crystals have an electron and hole mobility comparable with that of amorphous silicon, indicating that these novel materials are possible substitutes in technical applications. Despite many experimental and theoretical efforts, there remains still a lack of knowledge regarding basic transport parameters. For example the charge transport mechanism is highly dependent on the interplay between packing, the effective bandwidth and the nature of electron–phonon coupling and may vary from band‐like behavior to thermally activated hopping.On the other hand, charge transport across single molecules bridged between metallic leads shows complex conductance characteristics depending on the contact to the leads, molecule composition, and conformation. From both an experimental and theoretical point of view, these samples define benchmark systems for the analysis of principle contributions to the charge carrier transport.In‐between these limiting cases, organic thin films have established an emerging field of devices such as light emitting diodes, thin film transistors or photovoltaic cells. Due to controlled preparation of layered molecular structures with defined properties, some of these devices have already successfully entered the market and supply further motivation to study the underlying transport processes. Here the understanding of the impact of disorder on charge transport parameters is of crucial importance.All the above mentioned aspects have prompted us to organize an international summer school on ‘Charge Transport in Organic Materials’ which was held in September 2007 at the Physikzentrum Bad Honnef. The challenge of this school – with 19 invited key speakers and more than 140 students the biggest school ever organized in Bad Honnef – was to provide a bridge between the communities working on the transport phenomena of the various molecular systems.The following 15 articles emanate from this event and address many of the various aspects of transport in single crystals, films, and individual molecules, backed‐up by the corresponding theoretical approaches. The equal numbers of contributions indicate the exceptional balance between experiment and theory. All contributions are written by experts in the field and provide an up‐to‐date and in depth overview on the respective subjects.April 2008
Assessing the impact of ICH E9
Authors: Brown David , Day Simon , Hemmings Rob , Wright David 
Published: April 2008

AbstractThe ICH harmonized tripartite guideline ‘Statistical Principles for Clinical Trials’, more commonly referred to as ICH E9, was adopted by the regulatory bodies of the European Union, Japan and the USA in 1998. This document united related guidance documents on statistical methodology from each of the three ICH regions, and meant that for the first time clear consistent guidance on statistical principles was available to those conducting and reviewing clinical trials. At the 10th anniversary of the guideline's adoption, this paper discusses the influence of ICH E9 by presenting a perspective on how approaches to some aspects of clinical trial design, conduct and analysis have changed in that time in the context of regulatory submissions in the European Union. Copyright © 2008 John Wiley & Sons, Ltd.
Detection of nanoscale η‐MgZn2 phase dissolution from an Al‐Zn‐Mg‐Cu alloy by electrochemical microtransients
Authors: Wloka Joachim , Virtanen Sannakaisa 
Published: April 2008

AbstractIn this article we demonstrate how the dissolution of nanosize intermetallic particles present in Al alloys can be detected using microelectrochemical techniques. The local electrochemical properties of a high‐strength Al‐Zn‐Mg‐Cu alloy, which contains nanoscale η‐MgZn2 phases, were investigated with a microcapillary cell. At the open‐circuit potential (OCP) with the sample surface in the range of 1000 µm2, potential fluctuations (microtransients) can be observed. Under polarization of such small areas, current transients are detected in the passive range of the alloy. An estimation of the size of dissolution events from the charge passed during the current transient leads to the conclusion that the current transients could stem from the dissolution of η‐phase particles, with diameters in the order of 100 nm. This size scale corresponds well with the size of the grain‐boundary MgZn2. Transmission electron microscopy (TEM) and high‐resolution SEM images provide further insights for possible mechanisms leading either to potential or to current microtransients. Copyright © 2008 John Wiley & Sons, Ltd.
The developmental toxicity of 1‐methyl‐3‐octylimidazolium bromide on Daphnia magna
Authors: Luo Yan‐Rui , Li Xiao‐Yu , Chen Xiao‐Xiao , Zhang Bang‐Jun , Sun Zhen‐Jun , Wang Jian‐Ji 
Published: April 2008

AbstractThe developmental toxicity of 1‐methyl‐3‐octylimidazolium bromide ([C8mim]Br) on Daphnia magna was investigated. The 24 and 48 h LC50 values for [C8mim]Br in D. magna were 1.99 and 0.95 mg/L, respectively. A series of multigenerational toxicity tests were then used to explore [C8mim]Br effects in D. magna. [C8mim]Br significantly inhibited the body lengths of the F0 and F1 1st generations. After 21 days of exposure, [C8mim]Br lowered the reproductive ability of the F0 and F1 1st generations. In F1 3rd generation, 21 days of [C8mim]Br exposure prolonged the time to bear the first egg and the time to the first brood compared with the control, but the number of first‐brood offspring and the number of broods produced by these animals were reduced. After the recovery period all the reproductive parameters returned to normal in F1 1st generation except for the number of broods. The dead neonates increased with prolonged exposure and increasing concentrations, and the dead neonates of the F1 3rd generation went far beyond that of the F1 1st and F0 generations. The intrinsic rate of natural increase (r) values of the three D. magna generations significantly decreased after exposure to higher concentrations of [C8mim]Br compared with control groups. Collectively, these results suggest that [C8mim]Br exerts a toxic effect on the development of D. magna. This study also highlights the importance of systematically evaluating the potential effects of aquatic ecosystems of ionic liquids that may be released into bodies of water. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008.
Toxicological profiling of chemical and environmental samples using panels of test organisms and optical oxygen respirometry
Authors: Zitova Alice , O'Mahony Fiach C. , Cross Maud , Davenport John , Papkovsky Dmitri B. 
Published: April 2008

AbstractA simple and versatile methodology for high throughput toxicological assessment of chemical and environmental samples is presented. It uses panels of test organisms ranging from prokaryotic (E. coli, V. fischeri) and eukaryotic (Jurkat) cells to invertebrate (Artemia salina) and vertebrate (Danio rerio) organisms, to analyze alterations in their oxygen consumption by optical oxygen respirometry. All the assays are carried out in a convenient microtiter plate format using commercial reagents (phosphorescent oxygen probe, microplates) and detection on a standard fluorescent plate reader. Simple experimental set‐up and mix‐and‐measure procedure allow parallel assessment of up to 96 samples (or assay points) in 2 h, easy generation of dose‐ and time‐dependent responses, and EC50 values. The methodology was demonstrated with several different classes of chemicals including heavy metal ions, PAHs, pesticides, their mixtures, and also validated with complex environmental samples such as wastewater from a wastewater treatment plant. It has been shown to provide high sensitivity, sample throughput and information content, flexibility and general robustness. It allows ranking and profiling of samples, compares favorably with alternative methods such as MicroTox and mortality tests with animal models, and is well suited for large‐scale monitoring programs such as CWA and WFD. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.
Efficient representation of the attacker’s knowledge in cryptographic protocols analysis
Authors: Bertolotti Ivan Cibrario , Durante Luca , Sisto Riccardo , Valenzano Adriano 
Published: April 2008

Abstract
This paper addresses the problem of representing the intruder’s knowledge in the formal verification of cryptographic protocols, whose main challenges are to represent the intruder’s knowledge efficiently and without artificial limitations on the structure and size of messages. The new knowledge representation strategy proposed in this paper achieves both goals and leads to practical implementation because it is incrementally computable and is easily amenable to work with various term representation languages. In addition, it handles associative and commutative term composition operators, thus going beyond the free term algebra framework. An extensive computational complexity analysis of the proposed representation strategy is included in the paper.
Predictive Value of Sonographic Features in Preoperative Evaluation of Malignant Thyroid Nodules in a Multinodular Goiter
Authors: Salmaslıoğlu Artür , Erbil Yeşim , Dural Cem , İşsever Halim , Kapran Yersu , Özarmağan Selçuk , Tezelman Serdar 
Published: April 2008

AbstractBackgroundThe primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography.MethodsThis prospective study included 550 consecutive patients with, thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology.ResultsMicrocalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively).ConclusionAlthough we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.
Anal Sphincter Asymmetry in Anal Incontinence After Restorative Proctectomy for Rectal Cancer
Authors: Kang Sung‐Bum , Kim Nayoung , Lee Kyoung‐Ho , Kim Young‐Hoon , Kim Jee Hyun , Kim Jae‐Sung 
Published: April 2008

AbstractPurposeThe morphology and physiology of the anorectum can be altered after restorative proctectomy, which may result in anal incontinence. Thus far, there have been few reports regarding the specific characteristics and management of anal incontinence after rectal cancer surgery. We attempted to determine the characteristics of anorectum in anal incontinence after restorative proctectomy.MethodsWe compared the clinical and physiologic factors between consecutive 138 patients with continence and 48 with iatrogenic anal incontinence at 1 year after rectal cancer resection. This study excluded patients at less than 1 year after operation or ileostomy takedown.ResultsThe two groups were comparable with regard to age, sex ratio, radiotherapy, and complication rate. The percentages of asymmetry of the resting and squeeze sphincter were significantly higher in the anal incontinence group (37.2 ± 9.3% vs 32.5 ± 6.7%, P = 0.01; 32.4 ± 7.8% vs 28.3 ± 6.3%, P = 0.011). High‐pressure zone length, mean resting vector volume, and rectal compliance were not less in the anal incontinence group than in the continence group. In multivariate analysis of manometric variables, the percentages of asymmetry of the resting and squeeze were independent factors associated with anal incontinence (P < 0.05). The mean thickness of the anal cushion and internal anal sphincter did not significantly differ between the anal incontinence and continence groups.ConclusionSphincter asymmetry is one of the hallmark characteristics of iatrogenic anal incontinence patients after proctectomy, which suggests that anal canal symmetry may be a beneficial factor with regard to anal continence.