bluuebunny/crossref_metadata_2025_split huggingface dataset:
Employment status among adult survivors in the Childhood Cancer Survivor Study
Authors: Pang Jenny W.Y. , Friedman Debra L. , Whitton John A. , Stovall Marilyn , Mertens Ann C. , Robison Leslie L. , Weiss Noel S. 
Published: June 2007

AbstractBackgroundWith increased cure, childhood cancer survivors are reaching adulthood and seeking employment. Host, disease and treatment risk factors may contribute to inability to attain or maintain employment.ProcedureThe prevalence and risk factors for unemployment were evaluated using self‐reported employment history in 10,399 childhood cancer survivors and 3,083 siblings ≥ age 18 in the Childhood Cancer Survivor Study (CCSS).ResultsAmong survivors, 5.6% reported unemployment, compared with 1.2% of siblings (odds ratio [OR] 3.7; 95% confidence interval [CI] 2.6, 5.1). Increased risks were observed within all cancer diagnoses. In multivariate analysis, diagnosis of central nervous system (CNS) tumor (OR 1.5; 95% CI 1.1, 2.1), bone cancer (OR 1.5; 95% CI 1.0, 2.1), treatment with ≥30 Gy cranial radiotherapy (OR 4.0; 95% CI 2.9, 5.5), female gender (OR 1.4; 95% CI 1.2, 1.7) and age < 4 years at diagnosis (OR 1.4; 95% CI 1.1, 1.8) increased risk. Diagnosis of CNS or bone tumor or cranial radiotherapy ≥30 Gy remained significant after adjusting for treatment, medical late effects, age and gender. Risk of unemployment decreased with attained age (OR(year) 0.89; 95% CI 0.87, 0.91).ConclusionsCompared to siblings, adult childhood cancer survivors are at increased risk for unemployment with highest risk defined by diagnosis, treatment and demographic factors. Pediatr Blood Cancer 2008;50:104–110. © 2007 Wiley‐Liss, Inc.
Antidepressant use and off‐label prescribing in children and adolescents in Dutch general practice (2001–2005)
Authors: Volkers Anita C. , Heerdink Eibert R. , van Dijk Liset 
Published: June 2007

AbstractPurposeTo study the use of antidepressants in children and adolescents in Dutch general practice in 2001 and 2005 and to determine off‐label prescribing.MethodsData were obtained from the Netherlands Information Network of General Practice (LINH) that comprised 97 practices in 2001 and 73 practices in 2005. General practitioners (GPs) recorded prescriptions with their indication in the medical records of the patients during one calendar year. We selected boys and girls aged 0–17 years (n = 83 442 in 2001; n = 62 969 in 2005) and identified those who got prescribed antidepressants (N06A). Prevalence of use, indications and percentage of off‐label prescriptions were compared between 2001 and 2005.ResultsThe prevalence of selective serotonin reuptake inhibitor (SSRI) use decreased from 1.2 to 1.1 per 1000 children and adolescents between 2001 and 2005. The use of tricyclic antidepressants (TCAs) and other antidepressants also decreased (0.8 to 0.7 and 0.3 to 0.2, respectively). TCAs were often prescribed for nocturnal enuresis, but in patients aged 12–17 years hyperactivity was the leading indication in both years. GPs continued to prescribe SSRIs for depression (about half of the prescriptions) after the safety warnings, while venlafaxine prescribed for depression decreased in favour of anxiety. Off‐label prescribing of SSRIs increased from 16.7% to 34.4% and that of venlafaxine from 22.2% to 58.3%. All SSRI and venlafaxine prescriptions were unlicensed for age.ConclusionsThe decreased use of SSRIs and venlafaxine suggests an impact of the safety warnings. A point of concern is the enlarged off‐label prescribing and insight in the underlying reasons and its appropriateness is needed. Copyright © 2007 John Wiley & Sons, Ltd.
Coronary heart disease outcomes in patients receiving antidiabetic agents
Authors: McAfee Andrew T. , Koro Carol , Landon Joan , Ziyadeh Najat , Walker Alexander M. 
Published: June 2007

AbstractBackgroundThere is conflicting evidence on the reduction of cardiovascular risk in diabetic patients treated with oral antidiabetic agents.ObjectivesTo compare the risk of myocardial infarction (MI) and coronary revascularization (CR) in type 2 diabetic patients treated with rosiglitazone, metformin, or sulfonylurea.MethodsUsing data from a large US insurer, we created propensity‐matched cohorts. We identified hospitalizations for MI or CR. We calculated incidence rates and 95% confidence intervals for the outcomes and estimated risks from Cox proportional hazards models.ResultsWe identified 26,931 initiators of monotherapy, 4,086 initiators of dual‐therapy, and 2,346 initiators of combination with insulin therapy. There was no difference between the risk of the composite outcome with rosiglitazone monotherapy compared to metformin monotherapy (HR 1.07, 95% CI: 0.85, 1.34), and similarly with rosiglitazone monotherapy compared to sulfonylurea monotherapy (HR 0.82, 95% CI: 0.67, 1.02). There was no difference in the risk of outcome with rosiglitazone in combination with insulin therapy compared to other oral antidiabetic agents in combination with insulin (HR 0.88, 95% CI: 0.59, 1.32). Overall, there was little difference in the risk of the composite outcome or of the individual outcomes of MI and CR comparing rosiglitazone therapies to non‐rosiglitazone therapies (HR for composite outcome 0.93, 95% CI: 0.80, 1.10).ConclusionsThe results from the monotherapy and the dual‐therapy comparisons, though not individually significant, are consistent in suggesting that the risk of cardiovascular outcome events in patients using rosiglitazone may lie between the risks associated with sulfonylureas (higher incidence) and metformin (lower incidence). Copyright © 2007 John Wiley & Sons, Ltd.
Polymerization of carboxylic ester functionalized norbornenes catalyzed by (η3‐allyl)palladium complexes bearing N‐heterocyclic carbene ligands
Authors: Jung Il Gu , Seo Junhyeok , Chung Young Keun , Shin Dong Mok , Chun Sung‐Ho , Son Seung Uk 
Published: June 2007

AbstractAn in situ generated cationic allylpalladium complex bearing N‐heterocyclic carbene (NHC) ligands, derived from the reaction of [(η3‐C3H5)Pd(NHC)Cl] with AgX (X = BF4 or SbF6), is an active catalyst for the addition polymerization of norbornene and norbornene derivatives [5‐norbornene‐2‐carboxylic acid methyl ester (b) and 5‐norbornene‐2‐carboxylic acid n‐butyl ester (c)] with an ester group containing a large portion of endo‐isomers. The catalytic activities, polymer yields, molecular weights, and molecular weight distributions of polynorbornenes were investigated under various reaction conditions: the catalytic activity was highly dependent on the counteranion, the reaction solvent, and the reaction temperature. For b, as the portion of an endo‐isomer increased, the activity of 13(SbF) was much higher than those of 14 and 15, and for c (exo/endo = 95:5), the maximum turn over number (TON) was observed with 15(SbF). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3042–3052, 2007
Linear viscoelastic behavior of chitosan films as influenced by changes in the biopolymer structure
Authors: da Silva J. A. Lopes , Santos Carla A. N. S. 
Published: June 2007

AbstractFilms were prepared via solvent casting from different deacetylated and depolymerized chitosans obtained from β‐chitin. The linear viscoelastic behavior of the chitosan films was studied with uniaxial tensile stress–relaxation tests. All stress–relaxation profiles exhibited an asymptotically decaying trend, with a residual value different from zero, thus pointing out a solid‐like, viscoelastic behavior. The decay of the tensile modulus with time was phenomenologically described by a generalized Maxwell model consisting of three exponential functions and an equilibrium elastic modulus. Films prepared from chitosans with higher molecular weights showed higher residual elastic moduli and longer relaxation times. Within the range of the degrees of acetylation analyzed (0–27%), chitosans with the lowest and highest degrees of acetylation exhibited more pronounced solid‐like character. This behavior is explained on the basis of a complex balance between steric effects, types of intermolecular interactions, and aggregation of the chitosan samples. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1907–1915, 2007
The effect of nanoparticle shape on polymer‐nanocomposite rheology and tensile strength
Authors: Knauert Scott T. , Douglas Jack F. , Starr Francis W. 
Published: June 2007

AbstractNanoparticles can influence the properties of polymer materials by a variety of mechanisms. With fullerene, carbon nanotube, and clay or graphene sheet nanocomposites in mind, we investigate how particle shape influences the melt shear viscosity η and the tensile strength τ, which we determine via molecular dynamics simulations. Our simulations of compact (icosahedral), tube or rod‐like, and sheet‐like model nanoparticles, all at a volume fraction ϕ ≈ 0.05, indicate an order of magnitude increase in the viscosity η relative to the pure melt. This finding evidently can not be explained by continuum hydrodynamics and we provide evidence that the η increase in our model nanocomposites has its origin in chain bridging between the nanoparticles. We find that this increase is the largest for the rod‐like nanoparticles and least for the sheet‐like nanoparticles. Curiously, the enhancements of η and τ exhibit opposite trends with increasing chain length N and with particle shape anisotropy. Evidently, the concept of bridging chains alone cannot account for the increase in τ and we suggest that the deformability or flexibility of the sheet nanoparticles contributes to nanocomposite strength and toughness by reducing the relative value of the Poisson ratio of the composite. The molecular dynamics simulations in the present work focus on the reference case where the modification of the melt structure associated with glass‐formation and entanglement interactions should not be an issue. Since many applications require good particle dispersion, we also focus on the case where the polymer‐particle interactions favor nanoparticle dispersion. Our simulations point to a substantial contribution of nanoparticle shape to both mechanical and processing properties of polymer nanocomposites. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1882–1897, 2007
Phase equilibria of polymer dispersed liquid crystal systems in the presence of an external electrical field
Authors: Chen Tao , Zhang Liangshun , Li Tao , Lin Jiaping , Lin Shaoliang 
Published: June 2007

AbstractThe effect of an external electrical field on phase behaviors is reported for polymer dispersed liquid crystal films of 4′‐pentyl‐4‐biphenylcarbonitrile/poly(methyl methacrylate) binary mixtures with various polymer molecular weights. The experimental results show that increasing the molecular weight of the polymer or the electrical field intensity can give rise to an increase in the phase‐transition temperature and a widening of the binary phase region. The lattice theory, regarding a binary system consisting of a rigid nematic liquid crystal and a random polymer, has been extended to the case in which an external electrical field is present. A comparison of the theoretical predictions with the experimental results has been carried out, and satisfactory agreement has been found. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1898–1906, 2007
Molecular modeling of cellulose in amorphous state. III. An innovative elastomeric crosslink system
Authors: Chen Wei , Wang Tao , Lickfield Gary C. 
Published: June 2007

AbstractThe flexibility of molecular structures of rubber materials was evaluated using molecular modeling techniques to develop new crosslink agents which improve deformation recovery of cellulose without significant loss of the mechanical strength. Among the studied structures Poly(propylene oxide) (PPO) pentamer appears to be the most flexible and coiled one. Our calculation results showed that, cellulose crosslinked with PPO pentamers had similar deformation recovery to that crosslinked with DMDHEU. No conformation transitions were observed in these crosslinks when cellulose models were extended to 15% strain, which is consistent with the previous result that conformation transitions in crosslinks should be avoided upon extension to achieve a good recovery on crosslinked cellulose. In addition, PPO crosslinks did not significantly affect the breaking strain of cellulose based upon the cavity volume calculations, and they helped to remove the stress concentration among cellulose chains as suggested by the results of hydrogen bonding analysis. Thus, breaking strength of cellulose might not be significantly affected by PPO crosslinks as well. The preliminary experimental results confirmed above observations. Therefore, PPO pentamer appears to be a promising elastomeric backbone structure of crosslinking agents. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1821–1833, 2007
New classification of supersecondary structures of sandwich‐like proteins uncovers strict patterns of strand assemblage
Authors: Chiang Yih‐Shien , Gelfand Tatiana I. , Kister Alexander E. , Gelfand Israel M. 
Published: June 2007

AbstractTo describe the supersecondary structure (SSS) of β sandwich‐like proteins (SPs), we introduce a structural unit called the “strandon.” A strandon is defined as a set of sequentially consecutive strands connected by hydrogen bonds in 3D structures. Representing β‐proteins as the assembly of strandons exposes the underlying similarities in their SSS and enables us to construct a novel classification scheme of SPs. Classification of all known SPs is based on shared supersecondary structural features and is presented in the SSS database (http://binfs.umdnj.edu/sssdb/). Analysis of the SSS reveals two common specific patterns. The first pattern defines the arrangement of strandons and was found in 95% of all examined SPs. The second pattern establishes the ordering of strands in the protein domain and was observed in 82% of the analyzed SPs. Knowledge of these two patterns that uncover the spatial arrangement of strands will likely prove useful in protein structure prediction. Proteins 2007. © 2007 Wiley‐Liss, Inc.
A tetrapeptide fragment‐based design method results in highly stable artificial proteins
Authors: Dallüge Roman , Oschmann Jan , Birkenmeier Olaf , Lücke Christian , Lilie Hauke , Rudolph Rainer , Lange Christian 
Published: June 2007

AbstractComputational protein design has progressed rapidly over the last years. A number of design methods have been proposed and tested. In this paper, we report the successful application of a fragment‐based method for protein design. The method uses statistical information on tetrapeptide backbone conformations. The previously published artificial fold of TOP 7 (Kuhlman et al., Science, 2003; 302:1364–1368) was chosen as template. A series of polypeptide sequences were created that were predicted to fold into this target structure. Two of the designed proteins, M5 and M7, were expressed and characterized by fluorescence spectroscopy, circular dichroism and NMR. They showed the hallmarks of well‐ordered tertiary structure as well as cooperative folding/unfolding transitions. Furthermore, the two novel proteins were found to be highly stable against temperature and denaturant‐induced unfolding. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Using layer of protection analysis to define safety integrity level requirements
Authors: Freeman Raymond 
Published: June 2007

AbstractThe recent publication of ANSI/ISA standard S84.01 – 2004 defines the life safety cycle for the design and installation of safety instrumented functions (SIFs) using safety instrumented systems (SISs). However, the determination of the required safety integrity level (SIL) is an activity that the process designers need to complete prior to detailed design. This article outlines an approach for the determination of the required SIL using the layer of protection analysis (LOPA) method. An example is presented along with a suggested format for documenting the LOPA, SIL, and SIF requirements in a manner that can be transferred to the detailed design team for implementation. © 2007 American Institute of Chemical Engineers Process Saf Prog, 2007
Transport of a tripeptide, Gly‐Pro‐Hyp, across the porcine intestinal brush‐border membrane
Authors: Aito‐Inoue Misako , Lackeyram Dale , Fan Ming Z. , Sato Kenji , Mine Yoshinori 
Published: June 2007

AbstractThe transcellular transport of oligopeptides across intestinal epithelial cells has attracted considerable interest in investigations into how biologically active peptides express diverse physiological functions in the body. It has been postulated that the tripeptide, Gly‐Pro‐Hyp, which is frequently found in collagen sequences, exhibits bioactivity. However, the mechanism of uptake of dietary di‐ and tripeptides by intestinal epithelial cells is not well understood. In this study, we used porcine brush‐border membrane (BBM) vesicles to assess Gly‐Pro‐Hyp uptake, because these vesicles can structurally and functionally mimicin vivoconditions of human intestinal apical membranes. The present study demonstrated the time‐dependent degradation of this tripeptide into the free‐form Gly and a dipeptide, Pro‐Hyp, on the apical side of the BBM vesicles. In parallel with the hydrolysis of the tripeptide, the dipeptide Pro‐Hyp was identified in the BBM intravesicular space environment. We found that the transcellular transport of Pro‐Hyp across the BBM was inhibited by the addition of a competitive substrate (Gly‐Pro) for peptide transporter (PEPT1) and was pH‐dependent. These results indicate that Gly‐Pro‐Hyp can be partially hydrolyzed by the brush‐border membrane‐bound aminopeptidase N to remove Gly, and that the resulting Pro‐Hyp is, in part, transported into the small intestinal epithelial cells via the H+‐coupled PEPT1. Gly‐Pro‐Hyp cannot cross the epithelial apical membrane in an intact form, and Pro‐Hyp is highly resistant to hydrolysis by intestinal mucosal apical proteases. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Enumeration of carbohydrate hydroxyl groups by silylation and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Adeuya Anthony , Price Neil P. J. 
Published: June 2007

AbstractA method for enumerating hydroxyl groups in analytes is described and applied to various carbohydrates. The analytes were derivatized in solution by using trimethylsilylimidazole (TMSI) and the products were analyzed without chromatography by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS). The mass spectra revealed consecutive product ion peaks that are separated by 72 m/z units. This 72 m/z unit separation is a result of displacement of a hydroxyl hydrogen atom by a trimethylsilyl group. The number of the observed ions was used to confirm the number of hydroxyl groups in each analyte. This method was utilized in the analysis of single and multi‐component analytes. Published in 2007 by John Wiley & Sons, Ltd.
Nonminimum‐phase output tracking in causal systems using higher‐order sliding modes
Authors: Baev S. , Shtessel Y. , Shkolnikov I. 
Published: June 2007

AbstractAsymptotic output tracking in a class of causal nonminimum‐phase uncertain nonlinear systems is addressedviahigher‐order sliding modes (HOSMs). Local asymptotic stability of the output‐tracking error dynamics is provided. An output reference profile and an external disturbance forcing the internal dynamics are defined by an unknown linear exosystem. Its characteristic polynomial (which is used in the output‐tracking control algorithm) is identified online by using a HOSM parameter observer. A numerical example illustrates efficiency of the developed HOSM control algorithm. Copyright © 2007 John Wiley & Sons, Ltd.
Residual vibration suppression using Hankel iterative learning control
Authors: van de Wijdeven Jeroen , Bosgra Okko 
Published: June 2007

AbstractIn this paper, we present a new approach for suppression of residual vibrations in point‐to‐point motions based on lifted iterative learning control (ILC). The approach is to add a signal to the command input during the point‐to‐point motion in order to compensate for residual vibrations. A special form of ILC with separate actuation and observation time windows is shown to converge to the required signal. Subsequently, we present ILC control strategies for residual vibration suppression in which convergence and performance specifications can be designed separately. Additionally, the designed controllers have the capability to constrain the amplitude of the command signal. The presented strategies are demonstrated on a flexible system and shown to be successful in the suppression of residual vibration while minimizing the maximum amplitude of the command signal. Copyright © 2007 John Wiley & Sons, Ltd.
A new algorithm for high‐order sliding mode control
Authors: Plestan F. , Glumineau A. , Laghrouche S. 
Published: June 2007

AbstractA new robust high‐order sliding mode controller for a class of uncertain minimum‐phase single‐input–single‐output (SISO) nonlinear systems is designed. The high‐order sliding mode problem is formulated in input–output term and is viewed in uncertain linear context by considering uncertain nonlinear functions as bounded non‐structured parametric uncertainties. A sliding manifold is designed in order to ensure finite‐time convergence of sliding variable and its high‐order time derivatives. The control law allows the establishment of an rth‐order sliding mode. This result is extended to multi‐input–multi‐output (MIMO) systems. Copyright © 2007 John Wiley & Sons, Ltd.
On the Convergence of Fourier's Method for Nonlinear Wave‐Envelope Equations
Authors: Gajewski Herbert , Zacharias Klaus 
Published: June 2007

AbstractWe consider the initial value problem for a system of nonlinear wave‐envelope equations (Zakharov's system) of one‐dimensional plasma physics in the case of spatially periodic boundary conditions. A regularity property of the solution is shown which allows to prove the convergence of the Fourier approximation method.
Der Satz von Budan ‐ Fourier für allgemeine polynomiale Monosplines
Authors: Stieglitz Michael 
Published: June 2007

AbstractIst E = (eϱ) eine Inzidenzmatrix aus 0 und 1 und X eine feste Menge von Knoten χϱ, so gehört zu (E, X) die Menge der allgemeinen polynomialen Monosplines M vom Grad n, M(x):= \documentclass{article}\pagestyle{empty}\begin{document}$ M\left({x} \right)\,: = \frac{{x^n}}{{n!}} + \sum\limits_{v = 0}^{n - 1} {a_v x^v} + \sum\limits_{e_{\rho v} = 1} {a_{\rho v} \left({x - \xi _\rho} \right)_ + ^{n - 1 - v}} $\end{document}. Es wird zunächst eine obere Schranke für die Nullstellen von M im Intervall (0, 1) angegeben. Anwendungen betreffen dann solche Monosplines M, die aus Quadraturformeln entstehen, welche für Polynome vom Höchstgrad n—1 exakt sind. In diesem Fall muß eine zu E gehörige Matrix Ẽ der Pólya‐Bedingung genügen, und M hat im Intervall (0, 1) keine Nullstellen.
Anisotropic Hardening of Initially Orthotropic Materials
Authors: Dafalias Yannis F. 
Published: June 2007

AbstractA hardening model for an orthotropic material is proposed. The corresponding anisotropic parameters are the components of a fourth order tensor function of the plastic strain, entering a quadratic equation for the yield surface. Assuming polynomial dependence on the plastic strain, the most general form of a polynomial fourth order orthotropic tensor function of a second order symmetric tensor is constructed. This is obtained by imposing on the anisotropic parameters form‐invariance conditions under the orthogonal group of coordinate transformations associated with orthotropic symmetries. This yields the appropriate form of polynomial dependence of these parameters on the corresponding integrity basis. An interesting conclusion is that in addition to the initial orthotropic parameters, new anisotropic parameters appear with plastic strain. Kinematic hardening is also considered. The form‐invariance of the rate constitutive equations is discussed.