bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aqueous dispersions of polyurethane polyacrylic acid multiblock copolymers through living radical polymerization
Authors: Saimani Sundar , Tharanikkarasu Kannan , Radhakrishnan Ganga 
Published: December 2002

AbstractPolyurethane macroiniferter (PUMI) including tetraphenylethane was synthesized and used to prepare polyurethane–polyacrylic acid multiblock copolymers. Film‐forming aqueous dispersions without any added external emulsifiers were prepared from polyurethane–polyacrylic acid multiblock copolymers. The effect of varying PUMI content, polymerization time, and percent ionization on the properties of multiblock copolymeric dispersions were studied in detail. Interfacial tension of the dispersions and critical surface tension measurements of the films formed thereof have shown that the polymers exhibit a hydrophilic character in the dispersed phase and a hydrophobic character in the solid phase. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1109–1115, 2003
Influence of solvent on size of poly(p‐oxybenzoyl) whiskers prepared from p‐acetoxybenzoic acid
Authors: Kimura Kunio , Sarker Ashim Kumer , Ohmori Hideki , Yamashita Yuhiko 
Published: December 2002

AbstractPoly(p‐oxybenzoyl) (POB) crystals are prepared by the polymerization of p‐acetoxybenzoic acid (p‐ABA) at 320°C in various solvents to clarify the influence of miscibility between oligomer and solvent on the morphology as well as the size of the crystal. Concerning the morphology, whiskers are formed in less miscible solvents such as liquid paraffin and Barrel process oil B27. On the other hand, bundle‐like aggregates of fibrillar crystals tend to be formed in the solvents having higher miscibility such as Therm S 900 and 800, which are aromatic heat exchange media. Further, the solvents having higher temperature at which p‐ABA is completely dissolved during polymerization (Ts) yield a larger number of the whiskers with smaller width. The higher supersaturation of oligomers in less miscible solvents causes the formation of a larger number of nuclei with smaller size. Bundle‐like aggregates are formed in the solvents whose Ts is lower than 140°C by the fibrillation of pillar‐like crystals during polymerization owing to the reorganization. This shows a clear relationship between the width and Ts, and between the number of the crystals and Ts. Hence, the size of the whisker such as the length and the width can be predicted by the calculation with Ts, which is very valuable for the preparation of POB whiskers for use as industrial materials. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1129–1136, 2003
Induced crystallization of EVA having various VA contents by compressed CO2
Authors: Shieh Yeong‐Tarng , Lin Yen‐Gu 
Published: December 2002

AbstractThe crystallization induced by compressed CO2 was investigated for rubbery ethylene‐vinyl acetate copolymer (EVA) containing various amounts of vinyl acetate (VA). The induction of crystallization was demonstrated by appearance of shoulder‐like differential scanning calorimetry (DSC) endotherms at temperatures lower than Tm of polyethylene segments of EVA after CO2 treatments. The intensity of the endothermic shoulders and the degree of crystallinity increased with increasing VA content, suggesting that the interaction of CO2‐carbonyl groups governed the induction of crystallization of EVA upon CO2 treatment. The interaction of CO2‐carbonyl group was found to decrease with increasing temperature as demonstrated by the decreased crystallization enhancement for 37°C as compared with that for 32°C. The enhancement of crystallization did not monotonically increase with increasing CO2 pressure, resulting from the interplay of thermodynamic and kinetic driving forces, both being associated with the CO2 pressure and thus the sorption concentration. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1144–1151, 2003
Methodology for a project examining cognitive categories for library information in young children
Authors: Cooper Linda Z. 
Published: December 2002

AbstractThis article presents an overview of some of the methodology used in a project that examined children's understanding of library information and how those perspectives change in the first 5 years of formal schooling. Because our understanding of information is reflected in the manner in which we classify, or typify, that information in order to view the library collection from a child's perspective children were invited to shelve (i.e., classify) terms representative of library books and then to label those categories. The resulting shelf categories help us to see library information from a child's perspective. Data collection using group dialog, visual imagery, narrative, cooperative learning techniques, and hands‐on manipulatives is described for one session of a project in which children used induction to form concepts related to knowledge organization in a hypothetical library. Analysis for this session included use of hierarchical clustering and multidimensional scaling to examine and compare children's constructions for qualitative differences on several grade levels. Following the description of data collection methods and analysis, a discussion focuses on the reasons for using these particular methods of data collection with a child population.
“I spent 1 ½ hours sifting through one large box. …”: Diaries as information behavior of the archives user: Lessons learned
Authors: Toms Elaine G. , Duff Wendy 
Published: December 2002

AbstractThis article describes how diaries were implemented in a study of the use of archives and archival finding aids by history graduate students. The issues concerning diary use as a data collection technique are discussed as well as the different types of diaries.
Following experts at work in their own information spaces: Using observational methods to develop tools for the digital library
Authors: Gorman Paul , Lavelle Mary , Delcambre Lois , Maier David 
Published: December 2002

AbstractDigital libraries allow information access to be integrated into work processes rather than separated from them, but also have the potential to overwhelm users with excessive or irrelevant information, impairing their performance rather than improving it. With the opportunity to create new models of what a library is and how it can be used comes the challenge of improving our understanding of its patrons, their work, and the circumstances under which they perform it. In this article we offer an overview of our experiences using observational methods to learn about one class of users, expert clinicians treating patients in hospital settings. We describe the evolution of our understanding of the users and their informational tasks, and how this evolving understanding is guiding our efforts to create digital library technology. The multidisciplinary composition of our team has enriched our observations and improved the validity of our analysis and interpretations. The multiple observation methods we have employed, including “think‐aloud” scenarios in the laboratory, participant observation in the field, key informant interviews, and focus group sessions, have enabled us to enrich the data set, gain greater insight, and verify findings with informants. The relatively tight cycle of observation, analysis, development, and repeat observation has enabled us to iteratively and more rapidly refine our “user model” and “task model,” improving, we hope, the usefulness of the technologies we are developing.
Use of mutually inductive coupling in probe design
Authors: Hoult D.I. , Tomanek B. 
Published: December 2002

AbstractAn analysis is presented of mutually inductive coupling in probe design. It is assumed that near field couplings predominate and that lumped constants may therefore be employed. Using three published designs as examples, analytic techniques are presented for assessing B1 field strength, losses, and signal‐to‐noise ratio in increasingly complex situations. The perturbing effect of the B1 field from a matching coil is examined and it is shown that if the coil is too close to the sample there can be an asymmetry introduced in the rotating frame B1 field. It is then shown that such asymmetries are potentially a general feature of inductively coupled, loaded coils. The importance of suppressing unwanted resonances is highlighted if tuning and matching are to be orthogonal, a potential advantage of mutually inductive matching. Finally, a lumped‐constant simulation is briefly described for those situations where an analytic approach becomes too cumbersome. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 262–285, 2002
Optimal vibration control of continuous structures by FEM: Part I—the optimality equations
Authors: Szyszkowski W. , Grewal I. S. 
Published: December 2002

AbstractThe governing equations of the problem of optimal vibration control of continuous linear structures are derived in the form of a set of fourth‐order ordinary differential equations in the time domain. The equations decouple in the modal space and become suitable for handling by the FEM technique with the time domain subdivided into ‘finite time’ elements of class C1. It is demonstrated that the standard beam element with cubic Hermitian interpolation functions, routinely used in a static analysis of beams, can conveniently be substituted for the required ‘finite time’ element. Copyright © 2002 John Wiley & Sons, Ltd.
Wilson non‐conforming element in numerical manifold method
Authors: Cheng Y. M. , Zhang Y. H. , Chen W. S. 
Published: December 2002

AbstractNumerical manifold method (NMM) by Shi tries to unify the solution of problems in both continuous and discontinuous domains. Presently, NMM is commonly adopted on finite triangular and quadrilateral covers and the shape functions used in classical finite element analysis are also commonly adopted in manifold analysis. In this paper, the Wilson non‐conforming element is used in quadrilateral covers. The corresponding matrices of equilibrium equations are derived and a cantilever slab is considered. The results from the use of non‐conforming element in NMM are in good agreement with theoretical solution as compared with the classical Q4 isoparametric element. Copyright © 2002 John Wiley & Sons, Ltd.
A new perturbed multivariable finite element method with potential for DSAW computation in plates and layered solids
Authors: Zhang Wu , Shi Luye , Chen Yong , Guo Dingkang 
Published: December 2002

AbstractBased on extended Hamilton functional this paper constructs a new efficient yet accurate modified or perturbed multivariable electromechanical finite element method (FEM) with shift parameter and added potential for piezoelectric surface acoustic waves (PSAW) and disturbed surface acoustic waves (DSAW) with electrodes surface mounted, and investigates the numerical and comparative performances of p‐type multi‐variable plane strain, plate and generalized plane strain FEM. The shifted element methods are theoretically estimated a priori and numerically evaluated a posteriori. Incompatible modes are included and considered for generalized plate element methods. With the generality and validity discussed one new perturbed multivariable piezoelectric generalized plane strain FEM called PQ9 with potential is numerically found to be accurate and around 40% more efficient than traditional ones in multiplications and divisions, and will open possibilities of large‐scale multi‐periodic PSAW analysis, and save a huge amount of computer time and storage without losing assurance of accuracies. Although the shifted element matrices can indirectly lead to a small amount of spurious piezo‐hardening for free vibrations and bulk acoustic waves, numerical examples about ST‐cut crystal plate and plane element results show attractive merit and agreement with available analytical and test approaches for PSAW and DSAW studies. Copyright © 2002 John Wiley & Sons, Ltd.
Fetal cyclic motor activity in diabetic pregnancies: Sensitivity to maternal blood glucose
Authors: Robertson Steven S. , Dierker LeRoy J. 
Published: December 2002

AbstractSpontaneous fetal movement in the last third of human gestation is dominated by irregular oscillations on a scale of minutes (cyclic motility, CM). The core properties of these oscillations are stable during the third trimester of gestation in normal fetuses, but disrupted by poorly controlled maternal diabetes. Here we investigated whether fetal CM is linked to short‐term instabilities in maternal glucose metabolism. The fetuses of 40 mothers with type I (n = 28) or gestational (n = 12) diabetes were studied one to six times between 27 and 40 postmenstrual weeks of gestation. Fetal movement and maternal blood glucose concentration were measured during two separate periods of fetal activity in each session. Fetal CM was quantified with spectral analysis. Early in the third trimester, changes in the rate of oscillation in fetal CM between the two periods of activity were inversely related to changes in maternal blood glucose levels. Fetal CM was unrelated to concurrent maternal blood glucose levels at any point in the third trimester. The pattern of results suggests that disruption of the temporal organization of spontaneous fetal motor activity in pregnancies complicated by maternal diabetes represents an acute response to fluctuations in the metabolic environment rather than an alteration of CM development. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 9–16, 2003.
Radial maze proficiency of adult Wistar rats given prenatal complex magnetic field treatments
Authors: McKay B. E. , St‐Pierre L. S. , Persinger M. A. 
Published: December 2002

AbstractExposure to sinusoidal (power‐frequency) magnetic fields during prenatal development is implicated in adulthood behavioral impairments. However, the effects of prenatal exposure to weak‐intensity, nonsinusoidal complex magnetic fields (CMFs), an increasingly common feature of the modern environment, have not been rigorously examined. In the present study, male and female Wistar‐strain rats were exposed continually during prenatal development to one of three extremely low‐frequency CMFs or a sham condition. As adults, rats were trained in an acquisition/reversal radial maze task. All rats exposed to the prenatal CMFs increased their commission of reference memory errors, but differences in working memory and motivation to complete the maze task were specific to the type of prenatal CMF. These results provide the first evidence that prenatal exposures to specific shapes of CMFs impair complex learning behaviors into adulthood. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 1–8, 2003.
Maternal behavior changes after immune challenge of neonates with developmental effects on adult social behavior
Authors: Hood Kathryn E. , Dreschel Nancy A. , Granger Douglas A. 
Published: December 2002

AbstractTo examine whether maternal responsiveness during interactions with endotoxin‐treated pups contributes to long‐term effects on social development, neonatal mice were fostered on postnatal day 1 to dams from three selectively bred lines that differ in social behaviors. On day 5, neonates were administered saline or 0.5 mg/kg endotoxin (lipopolysaccharide, i.p.). Observations of undisturbed dams and litters on days 2, 4, 6, and 8 showed modest line differences in maternal behaviors. At the peak intensity of the transient illness induced by endotoxin (3 hr postinjection on day 5), dams increased licking and decreased time off‐nest for endotoxin, but not saline‐treated pups. As adults, fostered‐reared males were observed in brief social interactions. Males exposed to endotoxin early in life showed changes in adult social behaviors that depended on foster dam line as well as individual differences in maternal responsiveness. Maternal responsiveness to stressed neonates can ameliorate the social–developmental effects of early illness. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 17–34, 2003.
Neonatal social isolation alters both maternal and pup behaviors in rats
Authors: Zimmerberg Betty , Rosenthal Abigail J. , Stark Aleksandra C. 
Published: December 2002

AbstractThe development of emotional behavior is dependent on the early experiences of the infant and the quality of maternal care. In these experiments, the effects of social isolation during the preweaning period on both pup behavior and maternal responsivity were examined. In the first study, the number of ultrasonic vocalizations (USVs) emitted after brief maternal separation was measured in neonatal rats with differing histories of social isolation. The social isolation procedure consisted of 5 days of daily separation from the dam and littermates for either 3 or 6 hr. At both ages tested, socially isolated pups vocalized significantly less than control pups. In the second study, the effects of prior isolation either daily for 5 previous days (Chronic Isolation) or for 4 hr prior to testing (Acute Isolation) were examined in a T‐maze choice test. Pup vocalizations in the presence of the dam and dams' maternal behavior were assessed. When the dam was confined to the start box or during the maternal free access period, both Chronic and Acute Isolates vocalized less than pups that had never left the home nest. Dams spent more time with and licked and groomed more frequently and for a longer time both Chronic and Acute Isolates compared to pups that had always been with dams in the home nest. These results suggest that early isolation experience can alter subsequent responses to separation stress in neonatal rats and that maternal behavior is sensitive to the prior experiences of offspring. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 52–63, 2003.
Long‐term effects of infant rearing condition on the acquisition of dominance rank in juvenile and adult rhesus macaques (Macaca mulatta)
Authors: Bastian Meredith L. , Sponberg Anne C. , Sponberg Anne C. , Suomi Stephen J. , Higley J. Dee 
Published: December 2002

AbstractWe examined the effects of early rearing experience on the development of dominance status in 53 juvenile (age 3) and then in 38 adult (ages 5–8) rhesus macaques. Based on previous research investigating the behavioral outcomes of nursery‐rearing, we predicted that mother‐reared (MR) monkeys would outrank peer‐only reared (PR) monkeys, which would in turn outrank surrogate/peer‐reared (SPR) subjects. Juvenile MR and PR subjects did not differ in ranks, but monkeys from both rearing backgrounds outranked SPR cage‐mates at age 3. Independent of rearing condition, high‐ranking juveniles gained the most weight between ages 1–3, suggesting that low status may be associated with decreases in early weight gain. Adult MR subjects outranked both PR and SPR subjects, with PR animals occupying intermediate ranks. These results indicate that impoverished early experiences, such as adult absence and limited social interaction, are useful predictors of future social success in rhesus macaques. Published 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 44–51, 2003.
The neonatal rat as a developmental animal model of attention deficit hyperactivity disorder: Effects of frontal lesions on activity and learning
Authors: Mietus Bernadette A. , Johanson Ingrid B. , Terry Leslie M. 
Published: December 2002

AbstractWe examined a developmental animal model of Attention Deficit Hyperactivity Disorder (ADHD) by evaluating the effects of suppressed frontal cortical functioning on habituation in neonatal rats. Frontal cortical activity was suppressed with brain transections in neonatal rats 3, 6, 9, or 12 days of age. Pups were tested in a habituation‐to‐odor paradigm and behaviors (general activity, headwaving, probing, and rolling) were recorded. Frontal cortical suppression via brain transection resulted in significantly higher activity levels in 3‐day‐old rats, particularly with regard to rolling, suggesting that the frontal cortex is involved in the regulation of this age‐dependent behavior. Frontal transections also increased probing during the odor habituation test in 12‐day‐old pups. Results are consistent with the neuropsychological research regarding frontal cortical functioning and inhibition in children with ADHD, and suggest that neonatal rats with frontal lesions may provide a useful developmental animal model for studying ADHD. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 79–90, 2003.
On some Aitken‐like acceleration of the Schwarz method
Authors: Garbey M. , Tromeur‐Dervout D. 
Published: December 2002

AbstractIn this paper we present a family of domain decomposition based on Aitken‐like acceleration of the Schwarz method seen as an iterative procedure with a linear rate of convergence. We first present the so‐called Aitken–Schwarz procedure for linear differential operators. The solver can be a direct solver when applied to the Helmholtz problem with five‐point finite difference scheme on regular grids. We then introduce the Steffensen–Schwarz variant which is an iterative domain decomposition solver that can be applied to linear and nonlinear problems. We show that these solvers have reasonable numerical efficiency compared to classical fast solvers for the Poisson problem or multigrids for more general linear and nonlinear elliptic problems. However, the salient feature of our method is that our algorithm has high tolerance to slow network in the context of distributed parallel computing and is attractive, generally speaking, to use with computer architecture for which performance is limited by the memory bandwidth rather than the flop performance of the CPU. This is nowadays the case for most parallel. computer using the RISC processor architecture. We will illustrate this highly desirable property of our algorithm with large‐scale computing experiments. Copyright © 2002 John Wiley & Sons, Ltd.
A coarse grid extraction of sound signals for computational aeroacoustics
Authors: Djambazov G. S. , Lai C.‐H. , Pericleous K. A. , Wang Z.‐K. 
Published: December 2002

AbstractSound waves are propagating pressure fluctuations, which are typically several orders of magnitude smaller than the pressure variations in the flow field that account for flow acceleration. On the other hand, these fluctuations travel at the speed of sound in the medium, not as a transported fluid quantity. Due to the above two properties, the Reynolds averaged Navier1pt–1ptStokes equations do not resolve the acoustic fluctuations. This paper discusses a defect correction method for this type of multi‐scale problems in aeroacoustics. Numerical examples in one dimensional and two dimensional are used to illustrate the concept. Copyright © 2002 John Wiley & Sons, Ltd.
Optimized interface conditions for domain decomposition methods in fluid dynamics
Authors: Dolean Victorita , Lanteri Stéphane , Nataf Frédéric 
Published: December 2002

AbstractInterface conditions (IC) between subdomains have an important impact on the convergence rate of domain decomposition algorithms. We first recall the Schwarz method which is based on the use of Dirichlet conditions on the boundaries of the subdomains and overlapping subdomains. We explain how it is possible to replace them by more efficient ICs with normal and tangential derivatives so that overlapping is not necessary. It is possible to optimize the coefficients of the IC in order to achieve the best convergence rate. Results are given for the convection—diffusion equation. Then we consider the compressible Euler equations which form a system of equations. We present a new analysis of the use of interface conditions based on the flux splitting. We compute the convergence rate in the Fourier space. We find a dependence of their effectiveness on the Mach number M. For M=⅓, the convergence rate tends to zero as the wavenumber of the error goes to infinity. We stress the differences with the scalar equations. We present numerical results in agreement with the theoretical results. Copyright © 2002 John Wiley & Sons, Ltd.