bluuebunny/crossref_metadata_2025 huggingface dataset:
Ischemic Preconditioning Suppresses Ventricular Tachyarrhythmias After Myocardial Revascularization
Authors: Wu Zhong-Kai , Iivainen Tiina , Pehkonen Erkki , Laurikka Jari , Tarkka Matti R.
Published: December 2002

Background—

Ventricular fibrillation (VF) and tachycardia (VT) are the common and potential life-threatening complications after CABG. Ischemic preconditioning (IP) has been proved effective in reducing ischemia reperfusion arrhythmia in animals and humans. Whether IP is effective in suppressing postoperative VF/VT in patients with CABG has not been studied.

Methods and Results—

Eighty-six patients with CABG with stable and unstable 3-vessel disease were equally randomly assigned into an IP and a control group. The patients who received IP received 2 periods of 2-minute ischemia followed by 3-minute reperfusion. Twenty-four-hour electrocardiographic data were collected. IP resulted in fewer cases of VF after declamping (48.8% versus 79.1% in IP and control,
P
=0.004) and a shorter VF period (2.28±0.44 versus 4.41±0.51 minutes,
P
=0.002). The episodes of VT were significantly reduced in patients in the IP group during early reperfusion and 24 hours after reperfusion (0.65±0.16 versus 3.71±0.46,
P
=0.000 and 0.07±0.04 versus 2.12±1.41,
P
=0.002, respectively). De novo sustained VT occurred in 3 control patients as against none in the IP group after surgery. As a result, IP significantly curtailed the mechanical ventilation period and reduced the need for inotropes.

Conclusions—

IP significantly reduced postoperative VF/VT in patients with CABG with 3-vessel disease. Suppression of VT during early reperfusion and 24 hours after reperfusion suggests early and delayed IP phenomena in patients undergoing CABG surgery.
Coronary Flow Velocity Pattern Immediately After Percutaneous Coronary Intervention as a Predictor of Complications and In-Hospital Survival After Acute Myocardial Infarction
Authors: Yamamuro Atsushi , Akasaka Takashi , Tamita Koichi , Yamabe Kenji , Katayama Minako , Takagi Tsutomu , Morioka Shigefumi
Published: December 2002

Background—

Recently, it was reported that the degree of microvascular injury and left ventricular functional recovery during the chronic period can be predicted after treatment of the infarct-related artery based on the coronary flow velocity (CFV) pattern assessed using a Doppler guidewire. The aim of this prospective study was to examine whether the CFV pattern may predict complications and in-hospital survival after acute myocardial infarction (AMI).

Methods and Results—

The study population consisted of 169 consecutive patients with a first anterior AMI successfully treated with percutaneous coronary intervention (PCI). We examined the CFV pattern immediately after PCI using a Doppler guidewire. In accordance with previous findings, we defined severe microvascular injury as a diastolic deceleration time ≤600 ms and the presence of systolic flow reversal. Patients were divided into two groups: those without severe microvascular injury (n=118; group 1) and those with severe microvascular injury (n=51; group 2). All of the patients who had cardiac rupture were in group 2. Congestive heart failure (CHF) was observed more frequently in group 2 than in group 1 (53% versus 8%,
P
<0.001). The in-hospital cardiac mortality rate was significantly higher in group 2 than in group 1 (18% versus 0%,
P
<0.001). Nine patients in group 2 died, 5 patients because of CHF and 4 patients because of cardiac rupture.

Conclusions—

These findings suggest that the CFV pattern is an accurate predictor of the presence or absence of complications and of in-hospital survival after AMI.
Percutaneous Transcatheter Implantation of an Aortic Valve Prosthesis for Calcific Aortic Stenosis
Authors: Cribier Alain , Eltchaninoff Helene , Bash Assaf , Borenstein Nicolas , Tron Christophe , Bauer Fabrice , Derumeaux Genevieve , Anselme Frederic , Laborde François , Leon Martin B.
Published: December 2002

Background—

The design of a percutaneous implantable prosthetic heart valve has become an important area for investigation. A percutaneously implanted heart valve (PHV) composed of 3 bovine pericardial leaflets mounted within a balloon-expandable stent was developed. After ex vivo testing and animal implantation studies, the first human implantation was performed in a 57-year-old man with calcific aortic stenosis, cardiogenic shock, subacute leg ischemia, and other associated noncardiac diseases. Valve replacement had been declined for this patient, and balloon valvuloplasty had been performed with nonsustained results.

Methods and Results—

With the use of an antegrade transseptal approach, the PHV was successfully implanted within the diseased native aortic valve, with accurate and stable PHV positioning, no impairment of the coronary artery blood flow or of the mitral valve function, and a mild paravalvular aortic regurgitation. Immediately and at 48 hours after implantation, valve function was excellent, resulting in marked hemodynamic improvement. Over a follow-up period of 4 months, the valvular function remained satisfactory as assessed by sequential transesophageal echocardiography, and there was no recurrence of heart failure. However, severe noncardiac complications occurred, including a progressive worsening of the leg ischemia, leading to leg amputation with lack of healing, infection, and death 17 weeks after PHV implantation.

Conclusions—

Nonsurgical implantation of a prosthetic heart valve can be successfully achieved with immediate and midterm hemodynamic and clinical improvement. After further device modifications, additional durability tests, and confirmatory clinical implantations, PHV might become an important therapeutic alternative for the treatment of selected patients with nonsurgical aortic stenosis.
Solution properties of gas‐phase‐polymerized sodium acrylate microparticles. II. Sizing and thickening efficiencies
Authors: Sanderson R. D. , Sadiku E. R.
Published: December 2002

The application testing of sodium polyacrylate prepared by spray polymerization as a textile sizer was carried out. Six monomer samples of sodium acrylate, with concentrations ranging from 30 to 45%, were prepared, polymerized, and used on textile yarns to test the sizing and thickening efficiencies of the polymer. Of the six textile yarns treated with the size, only samples 5 and 6, which had the lowest monomer concentration of 30%, had an adequate sizing efficiency comparable to that of the commercial sodium polyacrylate. A Duplan breaking figure of 3 × blank (unsized) yarn (312 in this instance) or more is satisfactory for successful weaving on an industrial high‐speed loom. The two satisfactory samples had Duplan figures of 1067 and 1151, whereas the remaining four samples tested had Duplan values ranging from 393 to 769. The commercially available sodium polyacrylate size had a Duplan figure of 1146. For good sizing efficiency, therefore, a low monomer concentration of 30% or more in the preparation of sodium polyacrylate seemed desirable. Although the Duplan values for the two samples prepared with a monomer concentration of 45% (samples 1 and 2) were similar (419 and 398, respectively), the Duplan values of the samples prepared with a monomer concentration of 40% (samples 3 and 4) varied markedly (769 and 393, respectively). Samples 5 and 6, prepared with a lower monomer concentration (30%), exhibited similar Duplan values (1067 and 1151, respectively), which made them commercially acceptable as sizing agents. The thickening efficiency of the gas‐phase‐polymerized sodium polyacrylate was satisfactory when the polymer concentration was less than 0.2%. Above this concentration, the gas‐phase‐polymerized sodium polyacrylate had a low viscosity in comparison with that of the commercially available thickener. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1044–1050, 2003
Fiber–matrix interactions in aramid‐short‐fiber‐reinforced thermoplastic polyurethane composites
Authors: Vajrasthira Chanthipa , Amornsakchai Taweechai , Bualek‐Limcharoen Sauvarop
Published: December 2002

The mechanical and dynamic mechanical properties of thermoplastic polyurethane (TPU) elastomers reinforced with two types of aramid short fibers, m‐aramid (Teijin‐Conex) and copoly(p‐aramid) (Technora), were investigated in this study with respect to the fiber loading. In general, both types of composites exhibited very similar stress–strain behaviors, except that Technora–TPU was stronger than Conex–TPU. This was primarily due to the intrinsic strength of the reinforcing fibers. Both types of fibers reinforced TPU effectively without any surface treatment. This could be attributed to good fiber–matrix interactions, which were revealed by the broadening of the tan δ peak in dynamic mechanical analysis. Furthermore, the morphologies of cryogenically fractured surfaces of the composites and extracted fibers, investigated with scanning electron microscopy, revealed possible polar–polar interactions between the aramid fibers and TPU matrices. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1059–1067, 2003
Rheological properties of silicon polymer networks: The influence of the crosslink density
Authors: Robert C. , Crespy A. , Bastide S. , Lopez‐Cuesta J.‐M. , Kerboeuf S. , Artigue C. , Grard E.
Published: December 2002

This study was focused on the influence of the microstructural properties of a silicon polymer network on its rheological properties. Two commercial silicon oils were mixed in different ratios to form, by hydrosilylation, networks with different crosslink densities. The chemical compositions of the oils were determined by NMR, whereas their molecular weights and viscosities were studied with gel permeation chromatography and viscosimetry, respectively. The different networks were characterized through their crosslink densities. Afterward, the rheological properties were studied. The formulation notably influenced some characteristic values of the rheological behavior: the α‐transition temperature and the onset temperature of the caoutchoutic plateau shifted toward higher temperatures as the crosslink density increased, the storage modulus at the onset temperature of the caoutchoutic plateau increased with the crosslink density, and the amplitude of the peak associated with the α‐transition temperature decreased. These behaviors were explained as follows: as the crosslink density increased, a drastic decrease in the amount of free chains in the network occurred, and both phenomena induced a large decrease in the chain mobility, which might explain the aforementioned behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1152–1160, 2003
Gas‐phase ethylene polymerization using zirconocene supported on mesoporous molecular sieves
Authors: Kumkaew P. , Wanke S. E. , Praserthdam P. , Danumah C. , Kaliaguine S.
Published: December 2002

Mesoporous molecular sieves, with pore diameters of 2.6–25 nm, were impregnated with methylaluminoxane and bis(butylcyclopentadienyl)zirconium dichloride and tested as catalysts for the gas‐phase homopolymerization of ethylene at ethylene pressures of 200 psi and temperatures of 50–100°C and for 1‐hexene/ethylene copolymerization at 70°C. The activities and activity profiles, at constant Zr and Al contents, depended on the pore size of the supports and the polymerization temperature. Maximum activities for both the homopolymerizations and copolymerizations were observed for catalysts made with supports having pore diameters of 2.6 and 5.8 nm. Homopolymerization activities were highest at temperatures of 70–80°C; average homopolymerization and copolymerization activities up to 9000 kg of polyethylene/(mol of Zr h) were obtained. The weight‐average molecular weights (Mw's) were not a function of the support pore size but decreased with increasing reaction temperatures, from about 260,000 at 50°C to about 165,000 at 100°C. The polydispersities were essentially constant at 2.5 ± 0.2 for the homopolymers. Mw's for the 1‐hexene/ethylene copolymers had an average value of 117,000 with an average polydispersity of 2.8. The amount of triisobutyl aluminum added to the reactor significantly affected the activity and activity profiles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1161–1177, 2003
Dispersion polymerization of acrylamide with quaternary ammonium cationic comonomer in aqueous solution
Authors: Song B. K. , Cho M. S. , Yoon K. J. , Lee D. C.
Published: December 2002

Copolymer particles consisting of acrylamide (AM) and acryloyloxyethyl dimethylbenzyl ammonium chloride (AODBAC) were prepared by dispersion polymerization in an aqueous solution of ammonium sulfate and in the presence of poly(acryloyloxyethyl trimethyl ammonium chloride) (PAOTAC) as the stabilizer. The average particle size ranged from 4 to 7 μm, andMwandMnwere 2–6 ×106g/mol and 1–3 × 106g/mol, respectively. The effects of the AM/AODBAC ratio, monomer, initiator, salt, and stabilizer concentration on the particle size and molecular weight were studied. Increase of the AODBAC/AM ratio resulted in a decrease in the molecular weight and an increase in particle size. With the increase of the AODABA/AM ratio, the dispersion became less stable during long storage. Due to the presence of the salt, ionization of the quaternary ammonium groups in the dispersed particles is considered significantly suppressed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1101–1108, 2003
Aqueous dispersions of polyurethane polyacrylic acid multiblock copolymers through living radical polymerization
Authors: Saimani Sundar , Tharanikkarasu Kannan , Radhakrishnan Ganga
Published: December 2002

Polyurethane 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

Poly(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

The 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

This 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

This 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

Digital 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

An 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

The 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

Numerical 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

Based 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

Spontaneous 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

Exposure 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

To 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

The 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

We 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

We 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

In 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

Sound 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

Interface 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.
The hp mortar domain decomposition method for problems in fluid mechanics
Authors: Chilton Lawrence K. , Seshaiyer Padmanabhan
Published: December 2002

We consider the incompressible Stokes equations in primal velocity–pressure variables and present the mortar finite element formulation for this problem. The local approximation within each subdomain is designed using divergence stable hp‐mixed finite elements. The velocity is computed in a mortared space while the pressure is not subjected to any constraints across the interfaces. Our computational results show that the mortar finite element method for the Stokes problem satisfies similar rates of convergence as the conforming finite element method, in the presence of various h, p and hp discretizations (including the case of exponential hp convergence over geometric meshes). We also present the numerical results for the Lagrange multiplier when the method is implemented as a mixed method. Copyright © 2002 John Wiley & Sons, Ltd.
Parallel implementation of an optimal two level additive Schwarz preconditioner for the 3‐D finite element solution of elliptic partial differential equations
Authors: Nadeem S. A. , Jimack P. K.
Published: December 2002

This paper presents a description of the extension and parallel implementation of a new two level additive Schwarz (AS) preconditioner for the solution of 3‐D elliptic partial differential equations (PDEs). This preconditioner, introduced in Bank et al. (SIAM J. Sci. Comput. 2002; 23: 1818), is based upon the use of a novel form of overlap between the subdomains which makes use of a hierarchy of meshes: with just a single layer of overlapping elements at each level of the hierarchy. The generalization considered here is based upon the restricted AS approach reported in (SIAM J. Sci. Comput. 1999; 21: 792) and the parallel implementation is an extension of work in two dimensions (Concurrency Comput. Practice Experience 2001; 13: 327). Copyright © 2002 John Wiley & Sons, Ltd.
Differential response of primary and metastatic melanomas to neutrophils attracted by IL‐8
Authors: Schaider Helmut , Oka Masahiro , Bogenrieder Thomas , Nesbit Mark , Satyamoorthy Kapaettu , Berking Carola , Matsushima Kouji , Herlyn Meenhard
Published: December 2002

IL‐8 is a strong chemoattractant for neutrophils, and it is constitutively produced by many tumors, including human melanomas. To determine the biologic importance of IL‐8 for melanoma cells from primary and metastatic lesions, we transduced selected cell lines constitutively producing low levels of IL‐8 with IL‐8 cDNA using a replication‐deficient adenoviral vector. Nontumorigenic SBcl2 primary melanoma cells formed tumors when transduced with increasing plaque‐forming units of IL‐8 per cell. However, at high IL‐8 transduction levels (100 ng/ml/105 cells in 48 hr), tumor growth was impaired due to massive neutrophil infiltration. A similar biphasic response was observed in WM115 primary melanomas, which are tumorigenic but not metastatic. Depletion of neutrophils with an antibody that blocks the accumulation of granulocytes at the site of inflammation enabled transduced primary melanomas secreting high levels of IL‐8 to survive and grow. In contrast, highly tumorigenic and metastatic 451Lu cells showed marked increases in tumor growth and number of metastatic foci in the lungs depending on the expression levels of IL‐8. Cytotoxicity assays with isolated neutrophils confirmed the preferential killing of primary over metastatic melanoma cells. SBcl2 cells stimulated by IL‐8 to form tumors in immunodeficient mice were induced to produce VEGF, suggesting that the angiogenic response is enhanced due to increased growth factor production. Our results demonstrate that nontumorigenic primary melanomas depend on IL‐8 stimulation in vivo for growth and that tumor growth depends on the level of neutrophil infiltration. Metastatic melanomas proliferate in vivo independently of infiltrating neutrophils. © 2002 Wiley‐Liss, Inc.
The effect of melatonin treatment regimen on mammary adenocarcinoma development in HER‐2/neu transgenic mice
Authors: Anisimov Vladimir N. , Alimova Irina N. , Baturin Dmitri A. , Popovich Irina G. , Zabezhinski Mark A. , Manton Kenneth G. , Semenchenko Anna V. , Yashin Anatoly I.
Published: December 2002

The effect of various regimens of treatment with melatonin on the development of mammary tumors in HER2/neu transgenic mice was investigated. Female HER‐2/neu mice starting from the age of 2 months were kept under standard light/dark regimen and as given melatonin with tap water (20 mg/l) during the night time 5 times monthly (interrupted treatments) or constantly to natural death. Intact mice served as controls. Treatment with melatonin slowed down age‐related disturbances in estrous function most in the group exposed to interrupted treatment with the hormone. Constant treatment with melatonin decreased incidence and size of mammary adenocarcinomas, and incidence of lung metastases, compared to controls. The number of mice bearing 4 and more tumors was reduced in the group with constant melatonin treatment. Interrupted treatment with melatonin promote mammary carcinogenesis in HER‐2/neu transgenic mice. The data demonstrate the regimen‐dependent inhibitory effect of melatonin on the development of spontaneous mammary tumors in HER‐2/neu mice but not on overall survival with implication about the likely cause of the effect. Polycystic kidney disease is common in this transgenic line. Adverse effect of melatonin on the life span in our study may be unique to the transgenic model used and may not be relevant to the suppressive effect of melatonin in delay of mammary cancer. © 2002 Wiley‐Liss, Inc.
β2‐microglobulin induces caspase‐dependent apoptosis in the CCRF‐HSB‐2 human leukemia cell line independently of the caspase‐3, ‐8 and ‐9 pathways but through increased reactive oxygen species
Authors: Gordon John , Wu Ching‐Huang , Rastegar Mojgan , Safa Ahmad R.
Published: December 2002

Exogenous β2‐microglobulin (β2m) induces significant apoptosis in the CCRF‐HSB‐2 human lymphoblastic leukemia cell line as detected by DNA fragmentation, DAPI staining and annexin V binding assay. β2m treatment induced the release of cytochrome c and apoptosis‐inducing factor (AIF) from the mitochondria, but no change in mitochondrial membrane potential (ΔΨm) was observed during apoptosis, suggesting that cytochrome c may be released through a mechanism independent of mitochondrial permeability transition (MPT) pore formation. Moreover, the β2m‐induced release of cytochrome c and AIF from the mitochondria in CCRF‐HSB‐2 cells was caspase‐independent, since Z‐VAD‐fmk, a general inhibitor of caspases, did not block the release of these factors. However, Z‐VAD‐fmk treatment significantly blocked β2m‐induced apoptosis, while Western blot analysis revealed that caspases‐1, ‐2, ‐3, ‐6, ‐7, ‐8 and ‐9 are not activated during β2m‐induced apoptosis in these cells. These results collectively indicate that a post‐mitochondrial caspase‐dependent mechanism is involved in β2m‐induced apoptosis. Moreover, β2m significantly enhanced the production of reactive oxygen species (ROS) during 12–48 hr treatment, and β2m‐induced apoptosis was almost totally inhibited in cells pre‐treated with the antioxidant N‐acetylcysteine (NAC), providing evidence that β2m‐induced apoptosis in CCRF‐HSB‐2 cells is ROS‐dependent. Therefore, these results reveal that β2m‐induced apoptosis in CCRF‐HSB‐2 cells may occur through an unknown caspase‐dependent and ROS‐dependent mechanism(s) that is associated with cytochrome c and AIF release from mitochondria, but is independent of the caspase ‐3, ‐8 and ‐9 pathways. © 2002 Wiley‐Liss, Inc.
Prospective and randomised public‐health trial on neural network‐assisted screening for cervical cancer in Finland: Results of the first year
Authors: Nieminen Pekka , Hakama Matti , Viikki Merja , Tarkkanen Jussi , Anttila Ahti
Published: December 2002

Our objective was to evaluate the feasibility and relative validity of interactive neural network assisted screening (Papnet) in primary mass screening for cervical cancer as a public health policy (routine screening). A randomized, ongoing trial involved 152,969 invitees and 108,686 attendees in the organized mass screening in Finland in 1999. Drawing invitations from the population registry, women were randomized 2:1 at an individual level to have their smear analyzed either conventionally or with Papnet. The distribution of smears to different cytological categories, detection rates of dysplasias, in situ carcinomas and cancers were estimated with smears analyzed either conventionally (72,461) or by Papnet (36,225). A total of 108,686 smears were screened and 449 were histologically confirmed as dysplasias and carcinomas. The detection rates for histologically verified carcinoma in situ/severe dysplasia, moderate and mild dysplasias were 0.14%, 0.14% and 0.13% with conventional and 0.14%, 0.14% and 0.11% with Papnet, respectively. The detection rate of invasive cancer was 0.06‰ (n = 4) with conventional method and 0.08‰ (n = 3) with Papnet. None of the differences were statistically significant (p > 0.05). Papnet was able to identify 92.5% of healthy women (normal cytology), and the specificity of conventional smear was 92.9%. The positive predictive value (Pap Classes III–V) of Papnet was slightly but not significantly better (55% vs. 51%). Papnet screening was feasible as a part of routine screening and performed equally well compared to conventional one methods used in Finland. Organized mass screening was practiced very successfully in the last 38 years. We are going to continue the trial to study the potential trends in cervical cancer incidence in both study arms. © 2002 Wiley‐Liss, Inc.