bluuebunny/crossref_metadata_2025_split huggingface dataset:
Element‐based index reduction in electrical circuit simulation
Authors: Ebert Falk , Bächle Simone 
Published: January 2007

AbstractThe numerical simulation of very large scale integrated circuits is an important tool in the development of new industrial circuits. In the course of the last years, this topic has received increasing attention. Common modeling approaches for circuits lead to differential‐algebraic systems (DAEs). In circuit simulation, these DAEs are known to have index 2, given some topological properties of the network. This higher index leads to several undesirable effects in the numerical solution of the DAEs. Recent approaches try to lower the index of DAEs to improve the numerical behaviour. These methods usually involve costly algebraic transformations of the equations. Especially, for large scale circuit equations, these transformations become too costly to be efficient.We will present methods that change the topology of the network itself, while replacing certain elements in oder to obtain a network that leads to a DAE of index 1, while not altering the analytical solution of the DAE. This procedure can be performed prior to the actual numerical simulation. The decreasing of the index usually leads to significantly improved numerical behaviour. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlocal Boundary Conditions for Higher–Order Parabolic Equations
Authors: Ehrhardt Matthias , Zisowsky Andrea 
Published: January 2007

AbstractThis work deals with the efficient numerical solution of the two–dimensional one–way Helmholtz equation posed on an unbounded domain. In this case one has to introduce artificial boundary conditions to confine the computational domain. Here we construct with the Z –transformation so–called discrete transparent boundary conditions for higher–order parabolic equations schemes. These methods are Padé “Parabolic” approximations of the one–way Helmholtz equation and frequently used in integrated optics and (underwater) acoustics. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
General Inertia and Circle Criterion
Authors: Solmaz Selim , Mason Oliver , Shorten Robert 
Published: January 2007

AbstractIn this paper we extend the well known Kalman‐Yacubovic‐Popov (KYP) lemma to the case of matrices with general regular inertia. We show that the version of the lemma that was derived for the case of pairs of stable matrices whose rank difference is one, extends to the more general case of matrices with regular inertia and in companion form. We then use this result to derive an easily verifiable spectral condition for a pair of matrices with the same regular inertia to have a common Lyapunov solution (CLS), extending a recent result on CLS existence for pairs of Hurwitz matrices that can be considered as a time‐domain interpretation of the famous circle criterion. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Noncovalent‐wrapped sidewall functionalization of multiwalled carbon nanotubes with polyimide
Authors: Yang Zhi , Chen Xiaohua , Chen Chuansheng , Li Wenhua , Zhang Hua , Xu Longshan , Yi Bin 
Published: January 2007

AbstractMultiwalled carbon nanotubes (MWNTs) purified by sulfuric acid and nitric acid were functionalized with polyimide (PI) via an in situ polymerization in N,N‐diemethyformamide. The transmission electron microscopic and scan electron microscopic images showed that the functionalized MWNTs were wrapped by PI. The results of infrared, Raman, and UV–vis display that there was π‐π‐stacking interaction between imide and benzene ring in PI and the graphitic sidewalls of the MWNTs. The thermogravimetric analysis and differential scanning calorimetry results indicate that the thermal stability of the functionalized MWNTs with PI was improved. POLYM. COMPOS., 28:36–41, 2007. © 2007 Society of Plastics Engineers
Fatigue behavior of filament‐wound glass fiber reinforced epoxy composite tubes under tension/torsion biaxial loading
Authors: Qi Dongtao , Cheng Guangxu 
Published: January 2007

AbstractA study of filament‐wound glass fiber/epoxy composite tubes under biaxial fatigue loading is presented. The focus is placed on fatigue lives of tubular specimens under tension/torsion biaxial loading at low cycle up to 100,000 cycles. Filament‐wound glass‐fiber/epoxy tubular specimens with three different lay‐up configurations, namely [±35°]n, [±55°]n, and [±70°]n lay‐ups, are subjected to in‐phase proportional biaxial cyclic loading conditions. The effects of winding angle and biaxiality ratio on the multiaxial fatigue performance of composites are discussed. Specimens are also tested under two cyclic stress ratio: R = 0 and R = −1. The experimental results reveal that both tensile and compressive loading have an influence on the multiaxial fatigue strength, especially for [±35°]n specimens. A damage model proposed in the literature is applied to predict multiaxial fatigue life of filament‐wound composites and the predictions are compared with the experimental results. It is shown that the model is unsuitable for describing the multiaxial fatigue life under different cyclic stress ratios. POLYM. COMPOS. 28:116–123, 2007. © 2007 Society of Plastics Engineers
Thermally conductive silicone rubber reinforced with boron nitride particle
Authors: Zhou Wen‐Ying , Qi Shu‐Hua , Zhao Hong‐Zhen , Liu Nai‐Liang 
Published: January 2007

AbstractThermally conductive silicone rubber used as elastomeric thermal pad is successfully developed with boron nitride powder as conductive filler. The effects of content and particle size of filler on the thermal conductivity and mechanical property of silicone rubber are investigated. The results indicate that the use of hybrid boron nitride with three different particle sizes at a preferable weight ratio gives silicone rubber better thermal conductivity compared with each boron nitride with single particle size at the same total filler content. Furthermore, scanning electron microscopy, differential scanning calorimeter, thermogravimetric, etc., are used to characterize the morphology, curing behavior, thermal stability, and coefficient of thermal expansion (CTE) of the silicone rubber composites. POLYM. COMPOS., 28:23–28, 2007. © 2007 Society of Plastics Engineers
Perspectives on main‐chain hydrogen bonded supramolecular polymers
Authors: Shimizu Linda S 
Published: January 2007

AbstractSupramolecular polymers are assembled from monomeric units held together by reversible non‐covalent interactions. These supramolecular materials display polymeric properties and may soon have important industrial applications. This mini review focuses on the advances in main‐chain supramolecular polymers whose assembly is guided primarily by hydrogen bonding interactions. The design constraints of these new systems discussed include assembly motifs, the strength and directionality of the non‐covalent interactions, association versus reversibility, and environmental effects on the degree of polymerization. Selected literature examples including Meijer's ureidopyrimidinone system are used to highlight the challenges and potential of these supramolecular polymeric materials. Copyright © 2007 Society of Chemical Industry
Peer victimization and prosocial experiences and emotional well‐being of middle school students
Authors: Martin Kellie M. , Huebner E. Scott 
Published: January 2007

AbstractThis study investigated the relationships among different forms of peer victimization and prosocial experiences and early adolescent emotional well‐being. A total of 571 students in grades 6–8 were administered the Positive and Negative Affect Scale–Children, Multidimensional Students' Life Satisfaction Scale, and the Children's Self Experience Questionnaire–Self Report. Females reported more prosocial experiences; males reported more overt and relational victimization. Differential predictors were observed for the emotional well‐being variables of life satisfaction, positive affect, and negative affect in a series of hierarchical multiple regression equations. Overt victimization experiences added significant variance to all three well‐being equations. Relational victimization experiences added significant variance to the negative affect equation. After accounting for overt and relational experiences, prosocial experiences added significant variance to the life satisfaction and positive affect equations. The experience of prosocial peer interactions thus appears to serve as a protective factor with respect to the relationship between victimization and life satisfaction and positive affect for early adolescents. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 199–208, 2007.
Fatal asthma in finnish children and adolescents 1976–1998: Validity of death certificates and a clinical description
Authors: Malmström Kristiina , Kaila Minna , Kajosaari Merja , Syvänen Pirkko , Juntunen‐Backman Kaisu 
Published: January 2007

AbstractSeveral studies show that asthma mortality in children and adolescents increased until the mid‐1990s, after which it has slightly decreased worldwide. The objective of this study was to describe the mortality rates of childhood asthma in Finland, and to analyze patient characteristics to identify predisposing factors for fatal asthma exacerbation among children and adolescents during 1976–1998 (2004). All death certificates where asthma or related respiratory tract disease was coded as the underlying cause of death were reviewed for those under 20 years of age. Health care records and autopsy reports were evaluated to validate the cause of death and to identify any predisposing factors. In all, there had been 28 asthma deaths. The validity of the death certificates proved to be good as only 7% were misclassified. Death occurred either in the very young children or adolescents: the median age in the group of <12 years (n = 15) was 3.3 years while the median age in the group of >12 years (n = 13) was 18.1 years. The fatal exacerbations occurred mostly during summer and early autumn. Clinical triggers, recorded for 14/22 patients with available patient records, included respiratory infection, (12) use of ibuprofen despite known allergy (1), and exercise after visiting a horse stable (1). The severity of the disease was discernible in 21 patients: severe in 15, moderate in 5, and mild in 1 patient. Inhaled corticosteroids were not used as maintenance or periodic therapy in 12/22 patients, of whom 4 had died during the 1990s. In conclusion, asthma mortality in Finnish children and adolescents was rare and its incidence remained stable. The validity of the death certificate diagnoses proved to be good. Poor asthma management and non or undertreatment with inhaled corticosteroids were risk factors for fatal asthma. Pediatr Pulmonol. 2007; 42:210–215. © 2007 Wiley‐Liss, Inc.
Can direct field‐evaporation of doubly charged ions and post‐ionisation from the singly charged state co‐exist?
Authors: Ganetsos Th. , Mair A. W. R. , Mair G. L. R. , Bischoff L. , Akhmadaliev Ch. , Aidinis C. J. 
Published: January 2007

AbstractA tin liquid metal ion source (LMIS) containing ∼14% Pb has been studied. From a careful examination of the mass spectra of the source, it is concluded that post‐ionisation (PI) is the most probable mechanism for the formation of Pb2+ ions. In the case of tin, however, both Sn+ and Sn2+ appear to form by direct field‐evaporation. This view is supported by energy deficit measurements on the Sn+ and Sn2+ beams. Our results for Pb2+/Pb+ agree with those of Komuro with a pure Pb source. The reason for this is understandable and is related to the similarity between the evaporation fields of Sn and Pb. For the sake of completeness, we also present measurements of the energy spread of the Sn2+ and Sn+ beams. Copyright © 2007 John Wiley & Sons, Ltd.
The current stability of field emission cathodes of carbon nanotubes under ion bombardment
Authors: Bormashov Vitaly S. , Baturin Andrey S. , Nikolskiy Konstantin N. , Tchesov Roman G. , Sheshin Evgeniy P. 
Published: January 2007

AbstractThe degradation mechanism of field emission cathodes based on carbon nanotubes was investigated in the presented work. Emission current instability came from the adsorption/desorption processes on the cathode surface. During the long‐time tests, periodical variation of the electron work‐function (caused by switching on and off of the cathode) was detected. A model is proposed to explain the experimentally observed variations of electron work‐function. Copyright © 2007 John Wiley & Sons, Ltd.
Field emission from metal/polymer construction
Authors: Ionov A. N. , Popov E. O. , Svetlichnyi V. M. , Nikolaeva M. N. , Pashkevich A. A. 
Published: January 2007

AbstractWe investigated a large number of polymer materials. The parameters affecting their emission properties (namely, film thickness, temperature of polymer preparation, metal substrates and so on) were studied. We observed that the emission distributed over the full polymer surface with current densities up to several hundreds of µA/cm2. Some polymer samples showed high current emission properties up to 50 µA in d.c. and more than 1.5 mA in sinusoidal regimes. Copyright © 2007 John Wiley & Sons, Ltd.
Early stages of phase separation using three‐dimensional atom probe and atomistic modelling
Authors: Slabanja Mattias , Angenete Johan , Stiller Krystyna , Carling Karin M. , Wahnström Göran , Andrén Hans‐Olof 
Published: January 2007

AbstractThe early stages of clustering in Al‐14.8 Mg alloy have been studied using atomistic modelling and 3DAP analysis. Atomistic modelling was based on first‐principles quantum mechanical calculations and Monte Carlo (MC) based techniques. A good agreement between the experimental results and simulated data was obtained showing the appropriateness of the theoretical approach used. It has been shown that after 720 h at 35 °C (308 K) clustering of Mg was clearly detectable in the experimental alloy. The simulated data after 200 MC steps corresponded well to the experimental results obtained after ageing for 720 h. Copyright © 2007 John Wiley & Sons, Ltd.
Performance of a local electrode atom probe
Authors: Miller M. K. , Russell K. F. 
Published: January 2007

AbstractThe performance of a local electrode atom probe with a crossed delay line detector has been characterized. The local electrode atom probe with its short flight path and high speed (up to 250 kHz) pulse generator has made dramatic, orders of magnitude improvements in the data acquisition rate and the size of the analyzed volume compared to previous types of three‐dimensional atom probes. Sustained detection rates of up to 17% ions per field evaporation pulse have been achieved with data collection rates of up to 2 million atoms per minute. Preferential evaporation is substantially reduced due to the smaller proportion of time spent at the standing voltage enabling lower pulse fractions to be routinely used. A procedure for aligning the specimen with the aperture in the local electrode is described. Published in 2007 by John Wiley & Sons, Ltd.
Pain‐related self‐efficacy beliefs in a Brazilian chronic pain patient sample: a psychometric analysis
Authors: Sardá Jamir , Nicholas Michael K. , Pimenta Cibele A. M. , Asghari Ali 
Published: January 2007

AbstractWhile some people become severely or moderately disabled by chronic pain (pain that persists >3 months), others seem to adjust reasonably well to it. Higher levels of disability are often associated with higher levels of distress, and this relationship can be bidirectional resulting in a vicious cycle. There is evidence suggesting that self‐efficacy is one of the most important contributors to disability and emotional adjustment to chronic pain. Defining pain self‐efficacy beliefs as confidence in ability to function despite pain, the Pain Self‐Efficacy Questionnaire (PSEQ) has been widely used to examine the role of self‐efficacy in chronic pain patient populations. However, to date it has not been validated in Brazil. This study examined the reliability and validity of the PSEQ in a Brazilian chronic pain population. Data were collected from a convenience sample of 348 chronic pain patients. Reliability of the PSEQ has been found to be adequate (split‐half correlation was 0.76 and internal consistency was 0.90). Factor analysis indicated the existence of only one factor. Discriminant and concurrent validity were also adequate. Altogether these results indicate that the PSEQ has good psychometric properties when used in this sample. These findings are also consistent with those previously published in the literature. Copyright © 2007 John Wiley & Sons, Ltd.
Docking onto chromatin via the Saccharomyces cerevisiae Rad9 Tudor domain
Authors: Grenon Muriel , Costelloe Thomas , Jimeno Sonia , O'Shaughnessy Aisling , FitzGerald Jennifer , Zgheib Omar , Degerth Linda , Lowndes Noel F. 
Published: January 2007

AbstractAn integrated cellular response to DNA damage is essential for the maintenance of genome integrity. Recently, post‐translational modifications to histone proteins have been implicated in DNA damage responses involving the Rad9 family of checkpoint proteins. In budding yeast, methylation of histone H3 on lysine 79 (H3‐K79me) has been shown to be required for efficient checkpoint signalling and Rad9 localization on chromatin. Here, we have used a rad9 Tudor mutant allele and cells mutated for Dot1, the H3‐K79 methylase, to analyse the epistatic relationship between RAD9 and DOT1 genes regarding the DNA damage resistance and checkpoint activation pathways. Our results show that RAD9 is epistatic to DOT1 and suggest that it acts downstream of the Dot1 methylase in the damage resistance and checkpoint response. We have also found that the Tudor domain of Rad9 is necessary for in vitro binding to H3‐K79me as well as Rad9 focal accumulation in response to DNA damage in vivo. In summary, our study demonstrates that the interaction between Rad9, via its Tudor domain, and methylated H3‐K79 is required at two different steps of the DNA damage response, an early step corresponding to checkpoint activation, and a late step corresponding to DNA repair. The study further shows that the function of this interaction is cell cycle‐regulated; the role in checkpoint activation is restricted to the G1 phase and its role in DNA repair is restricted to G2. Copyright © 2007 John Wiley & Sons, Ltd.
Electrochemical properties of double wall carbon nanotube electrodes
Authors: Pumera Martin 
Published: January 2007

Abstract
Electrochemical properties of double wall carbon nanotubes (DWNT) were assessed and compared to their single wall (SWNT) counterparts. The double and single wall carbon nanotube materials were characterized by Raman spectroscopy, scanning and transmission electron microscopy and electrochemistry. The electrochemical behavior of DWNT film electrodes was characterized by using cyclic voltammetry of ferricyanide and NADH. It is shown that while both DWNT and SWNT were significantly functionalized with oxygen containing groups, double wall carbon nanotube film electrodes show a fast electron transfer and substantial decrease of overpotential of NADH when compared to the same way treated single wall carbon nanotubes.
Influence of soaking, fermentation and phytase supplementation on nutrient digestibility in pigs offered a grower diet based on wheat and barley
Authors: Lyberg K. , Lundh T. , Pedersen C. , Lindberg J. E. 
Published: January 2007

AbstractThe effects of 1-h soaking, fermentation and phytase supplementation of a pig diet based on wheat and barley on ileal and total tract apparent digestibility in growing pigs fitted with a post valve T-caecum (PVTC)-cannula were studied. Eight animals in a two-period change-over design were used, subjecting four animals to each treatment (dry, soaked, microbial phytase supplemented or fermented diet). Acid insoluble ash was used as an indigestible marker for calculating apparent digestibility coefficients. Fermentation improved (P<0·05) the ileal apparent digestibility coefficients of organic matter (OM), nitrogen and amino acids, while there was no effect of 1-h soaking and phytase supplementation. The total tract apparent digestibility coefficient of OM was also improved by fermentation. The ileal apparent digestibility coefficient of phosphorus (P) was higher for fermentation (P<0·05) than for dry food and 1-h soaking. The total tract apparent digestibility coefficient of P was higher (P<0·05) for treated food (soaked, fermented and supplemented with microbial phytase) compared with dry food. Fermentation improved (P<0·05) the ileal apparent digestibility coefficient of calcium compared with dry and soaked food, and had no effect on the total tract apparent digestibility coefficient of calcium. Food inositol phosphates were affected by treatment (P<0·05), with a reduction of P bound to inositol hexaphosphate (IP6) of 10% in the 1-h soaked food and of 80% in the fermented food. Degradation of IP6in the gastro-intestinal tract of the animals was lower in the fermented food than in the other treatments. The content of neutral-detergent fibre in the food was reduced (P<0·05) in the soaked and fermented food by 4% and 14%, respectively, compared with the dry food. In conclusion, fermentation of food can improve digestibility of OM, degrade IP6and increase ileal digestibility of phosphorus, nitrogen and amino acids.
Dose effect of live yeasts on rumen microbial communities and fermentations during butyric latent acidosis in sheep: new type of interaction
Authors: Brossard L. , Chaucheyras-Durand F. , Michalet-Doreau B. , Martin C. 
Published: January 2007

AbstractSix ruminal cannulated Texel sheep were used to assess the dose response and the effect of live yeasts (Levucell® SC, Saccharomyces cerevisiae CNCM I-1077) on the prevention of induced ruminal latent acidosis. The sheep received, in a replicated 3×3 Latin-square design, an acidotic diet (wheat +lucerne hay, 60:40 (dry matter (DM) basis); starch: 410 g/kg DM) without yeast (control group; L0 treatment), supplemented with 0·2 g/day yeast (4×109colony-forming units (c.f.u.) per day corresponding to producer recommendations; L1 treatment) or with 2 g/day yeast (4×1010c.f.u. per day; L10 treatment). The following measurements were carried out: food intake, ruminal pH, ruminal volatile fatty acids (VFA), lactate and ammonia (NH3) concentrations, protozoal and lactate-utilizing bacterial counts, relative proportions of two main bacteria implicated in lactate metabolism (a lactate-producing species, Streptococcus bovis, and a lactate-utilizing species, Megasphaera elsdenii) using specific 16S-rRNA-targeting oligonucleotide probes, activities of lactate dehydrogenase (LDH) and of polysaccharidases involved in plant cell wall (xylanase, carboxymethylcellulase) and starch (amylase) degradation. The acidotic diet (L0) induced a butyric (12 mol per 100 mol total VFA) rather than lactic (<4 mmol/l) ruminal latent acidosis. Ruminal pH, fermentative patterns, lactate-metabolizing bacteria (concentration, LDH activity) and polysaccharidase activities were similar between treatments (P>0·1). Yeast supplementation tended to increase ruminal protozoal population (P<0·1) and intake of animals (P<0·1). The recommended yeast concentration (L1) was sufficient to ensure these effects. The yeast's action may differ according to the nature and function of the micro-organisms involved and the type of fermentative pattern favoured (protozoa/butyrate v. lactate-metabolizing bacteria/lactate and propionate) during ruminal acidosis in sheep.