bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distributed behavior arbitration network: Autonomous behavior control architecture for humanoids
Authors: Shimizu Masaharu , Furuta Takayuki , Tomiyama Ken 
Published: August 2002

AbstractA new concept of decentralized behavior control architecture for humanoids, termed the Distributed Behavior Arbitration Network, is proposed in this paper. First, policies for constructing the architecture are discussed and then the proposed architecture is designed according to these policies. In the proposed architecture, each competence of a humanoid is differentiated based on the behavior‐based framework and individual agents represent these differentiated competences. An agent consists of NetIBSI, which describes behavior patterns of the agent using state transition network, and the Conflict Resolution Strategy, which mediates with other agents. Autonomous distributed cooperation among agents becomes possible through these two components. The effect of the cooperation among multiple agents is to achieve various behavior patterns for humanoids. The proposed architecture was implemented in two types of humanoids constructed in our laboratory. It was able to realize fall avoidance behavior that required quick response and goal search behavior that required cooperation between two agents. The obtained results demonstrate that the proposed architecture is capable of generating complicated and intelligent behaviors for humanoids. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(6): 32–43, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1130
Adhesion, lubrication and wear on the atomic scale
Authors: Adams James B. , Hector Louis G. , Siegel Donald J. , Yu Hualiang , Zhong Jun 
Published: August 2002

AbstractThis paper reviews three important aspects of tribology (adhesion, lubrication and wear) on the atomic scale with a focus on our work on aluminum surfaces. Adhesion is critical to the success of many applications but there is no simple analytical model available to predict adhesion between different materials, so we discuss the use of electronic structure methods to investigate adhesion between Al and various ceramics to determine the factors that control adhesion. Lubricants used to control friction usually include ‘boundary additives’ to bind the lubricant more strongly to the surface, so that higher stresses can be employed and wear can be reduced. Little is known about how boundary additives bond to Al surfaces, so we used electronic structure methods to investigate that phenomenon. Regarding wear, we review the literature on molecular dynamics simulations to investigate nanoindentation and wear. We discuss our molecular dynamics simulations of nanoindentation and asperity–asperity shear and the effect of temperature, loading rate, interaction strength and geometry. Copyright © 2001 John Wiley & Sons, Ltd.
Selection models and pattern‐mixture models to analyse longitudinal quality of life data subject to drop‐out
Authors: Michiels Bart , Molenberghs Geert , Bijnens Luc , Vangeneugden Tony , Thijs Herbert 
Published: August 2002

AbstractLongitudinally observed quality of life data with large amounts of drop‐out are analysed. First we used the selection modelling framework, frequently used with incomplete studies. An alternative method consists of using pattern‐mixture models. These are also straightforward to implement, but result in a different set of parameters for the measurement and drop‐out mechanisms. Since selection models and pattern‐mixture models are based upon different factorizations of the joint distribution of measurement and drop‐out mechanisms, comparing both models concerning, for example, treatment effect, is a useful form of a sensitivity analysis. Copyright © 2002 John Wiley & Sons, Ltd.
Investigating causes of heterogeneity in systematic reviews
Authors: Glasziou P. P. , Sanders S. L. 
Published: August 2002

AbstractWhat causes heterogeneity in systematic reviews of controlled trials? First, it may be an artefact of the summary measures used, of study design features such as duration of follow‐up or the reliability of outcome measures. Second, it may be due to real variation in the treatment effect and hence provides the opportunity to identify factors that may modify the impact of treatment. These factors may include features of the population such as: severity of illness, age and gender; intervention factors such as dose, timing or duration of treatment; and comparator factors such as the control group treatment or the co‐interventions in both groups. The ideal way to study causes of true variation is within rather than between studies. In most situations however, we will have to make do with a study level investigation and hence need to be careful about adjusting for potential confounding by artefactual factors such as study design features. Such investigation of artefactual and true causes of heterogeneity form essential steps in moving from a combined effect estimate to application to particular populations and individuals. Copyright © 2002 John Wiley & Sons, Ltd.
Power and sample size requirements for two‐part models
Authors: Lachenbruch Peter A. 
Published: August 2002

AbstractTwo‐part models assume the data has a probability mass at zero and a continuous response for values greater than 0. We construct tests based on the proportion of zeros and the difference among the positive values of a response giving rise to a two degree of freedom χ2 test. This note gives the non‐centrality parameter and finds the power for the test. The power is compared to the simulation results in a recent paper. We derive sample size calculations. We note that some modifications of this procedure may provide better tests if the non‐zero responses are discrete. Published in 2001 by John Wiley & Sons, Ltd.
Two goodness‐of‐fit tests for logistic regression models with continuous covariates
Authors: Pulkstenis Erik , Robinson Timothy J. 
Published: August 2002

AbstractAssessing goodness‐of‐fit in logistic regression models can be problematic, in that commonly used deviance or Pearson chi‐square statistics do not have approximate chi‐square distributions, under the null hypothesis of no lack of fit, when continuous covariates are modelled. We present two easy to implement test statistics similar to the deviance and Pearson chi‐square tests that are appropriate when continuous covariates are present. The methodology uses an approach similar to that incorporated by the Hosmer and Lemeshow goodness‐of‐fit test in that observations are classified into distinct groups according to fitted probabilities, allowing sufficient cell sizes for chi‐square testing. The major difference is that the proposed tests perform this grouping within the cross‐classification of all categorical covariates in the model and, in some situations, allow for a more powerful assessment of where model predicted and observed counts may differ. A variety of simulations are performed comparing the proposed tests to the Hosmer–Lemeshow test. Copyright © 2002 John Wiley & Sons, Ltd.
Residual‐based tree‐structured survival analysis
Authors: Keleş Sündüz , Segal Mark R. 
Published: August 2002

AbstractExtensions of various non‐parametric regression techniques (for example, additive models, trees, MARS) have been devised for right censored survival data. These approaches directly handle the difficulties posed by censoring. However, it is possible to bypass these difficulties by utilizing standard non‐parametric regression procedures applied with (say) martingale residuals as outcome. Analytic correspondences between the direct and residual‐based approaches have been established for additive models while more qualitative comparisons have been provided for MARS. Here we develop such correspondences for tree‐structured regression. In particular, we provide an analytic relationship between logrank and martingale residual sum‐of‐squares split functions that explains the widely observed similarity of the resultant trees. Further investigation is provided by simulation and an illustrative example using time to AIDS with data deriving from a Western Australian HIV cohort study. Copyright © 2002 John Wiley & Sons, Ltd.
Eleutherococcus senticosus reduces cardiovascular stress response in healthy subjects: a randomized, placebo‐controlled trial
Authors: Facchinetti F. , Neri I. , Tarabusi M. 
Published: August 2002

AbstractThe number of studies devoted to the scientific evaluation of phytotherapy is rapidly increasing since Western patients seem more oriented towards so‐called ‘alternative medicine’. Bearing such arguments in mind we decided to address attention to Eleutherococcus senticosus, a root of the Ginseng family known for thousands of years in China as a remedy for psychological distress. Forty‐five paid, healthy volunteers (20 males, 25 females) were recruited. Entry criteria were: good health, age 18–30 years, student and a Symptoms Rating Test score <10. At screening evaluation subjects were randomized to receive orally either placebo (Pl group) or Eleutherococcus senticosus (Es group) for 30 days, in a double‐blind design. Subjects were submitted to a stressful cognitive task, the Stroop Colour–Word test (Stroop CW), both before and after treatment. Stroop CW increased heart rate (HR) and systolic BP in every subject. In females there was a greater response than in males in terms of both systolic and diastolic BP. For both genders, the HR response to Stroop CW was reduced by Es treatment while no changes were found after Pl. In females, systolic BP was also reduced in Es group while it remained unchanged in Pl group. This study demonstrated that treatment with Eleutherococcus senticosus is able to reduce cardiovascular responses to stress in healthy young volunteers, while placebo was ineffective. Eleutherococcus senticosus is confirmed to be helpful for stress adaptation. Copyright © 2002 John Wiley & Sons, Ltd.
Health, performance and emotional intelligence: an exploratory study of retail managers
Authors: Slaski Mark , Cartwright Susan 
Published: August 2002

AbstractContemporary theories place emotions and self‐regulation at the centre of a dynamic process of stress. Emotional Intelligence (EQ) is the ability to perceive, understand and reflectively manage one's own emotions and those of others. This study, which was situated within the management population (n = 224) of a large retail organization, investigates the relationship between a measure of EQ, subjective stress, distress, general health, morale, quality of working life and management performance. Significant correlations in the expected direction were found, indicating that managers who scored higher in EQ suffered less subjective stress, experienced better health and well‐being, and demonstrated better management performance. Copyright © 2002 John Wiley & Sons, Ltd.
The quest for competence in systemic research and practice
Authors: Ulrich Werner 
Published: August 2002

AbstractHow can we develop competence in research and professional practice? This essay tries to answer the question from the perspective of critical systems thinking, that is, through an approach that aims to promote reflective research and practice. The paper originated in discussions on the nature of research, with research students and professionals from different fields—among these the domains of business and public management, operational research and management science, social planning and evaluation research, public health, poverty research, social work and social policy, environmental research, city and regional planning, adult education and civic studies. With its publication the author hopes to encourage a wide readership of research students, researchers and professionals in these and other fields of practice who wish to clarify their personal notion of competence. The essay addresses them in a direct and personal way. Copyright © 2001 John Wiley & Sons, Ltd.
Antiapoptotic and cytotoxic properties of delta opioid peptide [D‐Ala2,D‐Leu5]enkephalin in PC12 cells
Authors: Hayashi Teruo , Tsao Li‐I , Su Tsung‐Ping 
Published: August 2002

AbstractThe delta opioid peptide [D‐Ala2,D‐Leu5]enkephalin (DADLE) has been shown to promote organ survival and to protect against methamphetamine‐induced neurodegeneration. However, the cellular mechanisms of these actions of DADLE are not totally clear. We examined the action of DADLE in serum‐deprived pheochromocytoma cells (PC12) and found that DADLE protected against cell death in those cells. However, the dose–response curves of the protective effects of DADLE are U‐shaped as judged by three biochemical or morphological assays: the LDH release, the DNA laddering, and the apoptotic nuclei. It was found that femtomolar to picomolar concentrations of DADLE are antiapoptotic, whereas micormolar concentrations of DADLE are cytotoxic in PC12 cells. The protective effect of DADLE could be attenuated by a selective delta2 opioid antagonist and the cytotoxic action of DADLE was reduced by a selective mu opioid receptor antagonist. The treatment of cells with PD98059, a selective inhibitor of ERK kinase (MEK), or the transfection of cells with a dominant interfering form of MEK (MEK‐KA97) blocked both the protective effect of DADLE and the ERK phosphorylation induced by DADLE. Cytotoxic concentrations of DADLE, on the other hand, caused an increase of Fas‐ligand (FasL) in PC12 cells that was attenuated by a selective mu antagonist. Our results suggest, therefore, that endogenous opioid peptides may, at low concentrations, promote cell survival via the MEK‐ERK pathway perhaps through delta2 opioid receptors, whereas they may kill cells at high concentrations via the activation of FasL through an as‐yet unknown mechanism involving mu opioid receptors. Synapse 43:86–94, 2002. © 2001 Wiley‐Liss, Inc.
Evidence for activation of histamine H3 autoreceptors during handling stress in the prefrontal cortex of the rat
Authors: Westerink Ben H.C. , Cremers Thomas I.F.H. , De Vries Jan B. , Liefers Hans , Tran Nan , De Boer Peter 
Published: August 2002

AbstractOn‐line microdialysis of histamine in 10‐min samples of the prefrontal cortex of the conscious rat is described. The HPLC‐fluorescent assay for histamine in dialysates has been significantly simplified by using only one postcolumn reagent line instead of the three reagent lines described in earlier methods. The method is selective, sensitive (detection limit: 2–3 fmol on column), and linear over a large concentration range. Basal values of histamine decreased to about 50% of basal levels during infusion of tetrodotoxin (5 × 10‐6 M). Handling rats for 15 min increased histamine in dialysates to about 300% of basal levels. When tetrodotoxin (10‐6 M) was applied during handling the increase in histamine release was strongly (about 80%) suppressed. The handling‐induced increase in histamine was used as a paradigm to investigate the functional activity of histamine H3 autoreceptors during mild stress or arousal. An H3 receptor specific agonist (α‐methylhistamine; 10‐5 M) and antagonist (thioperamide; 10‐5 M) were infused into the frontal cortex via the microdialysis probe. The effect of handling on histamine release was potentiated during infusion of thioperamide and fully suppressed during infusion of α‐methylhistamine. These results clearly illustrate the efficacy of the H3 autoreceptor in modulating stimulated histamine release during natural stimulatory conditions. Synapse 43:238–243, 2002. © 2002 Wiley‐Liss, Inc.
In vivo binding properties of [carbonyl‐11C]WAY‐100635: Effect of endogenous serotonin
Authors: Maeda Jun , Suhara Tetsuya , Ogawa Masanao , Okauchi Takashi , Kawabe Kouichi , Zhang Ming‐Rong , Semba Jun'Ichi , Suzuki Kazutoshi 
Published: August 2002

Abstract[Carbonyl‐11C]WAY‐100635 has been reported to be a useful ligand for the investigation of 5‐HT1A receptor imaging in vivo. However, the cellular distribution and the influence of endogenous serotonin (5‐HT) on in vivo binding have not been fully examined. In this study, we investigated the effect of 5,7‐dihydroxytryptamine‐produced destruction of 5‐HT neurons, reserpine‐induced 5‐HT depletion, and fenfluramine‐induced 5‐HT increase on [carbonyl‐11C]WAY‐100635 binding in vivo. There was no significant change in the uptake of [carbonyl‐11C]WAY‐100635 in the slice of 5‐HT denervated rat brain except in the raphe nucleus, where 5‐HT cell bodies exist. There was no obvious effect of enhanced 5‐HT release by fenfluramine or decreased release by reserpine on [carbonyl‐11C]WAY‐100635 binding in the dissected brain region. No significant effect was observed in the time course of [carbonyl‐11C]WAY‐100635 in the hippocampus and frontal cortex measured by PET. These results indicated that the in vivo binding of [carbonyl‐11C]WAY‐100635 in the hippocampus and cerebral cortex mainly reflects postsynaptic 5‐HT1A receptor binding, and that this binding is not sensitive to endogenous 5‐HT. Synapse 40:122–129, 2001. © 2001 Wiley‐Liss, Inc.
Differential behavioral responses to cocaine are associated with dynamics of mesolimbic dopamine proteins in Lewis and Fischer 344 rats
Authors: Haile Colin N. , Hiroi Noboru , Nestler Eric J. , Kosten Therese A. 
Published: August 2002

AbstractDifferential behavioral and biochemical responses to drugs of abuse may reflect genetic makeup as suggested by studies of inbred Lewis (LEW) and Fischer 344 (F344) rats. We investigated locomotor activity, stereotypy signs, and levels of specific proteins in the nucleus accumbens (NAc) and ventral tegmental area (VTA) in these strains at baseline and following chronic administration of cocaine (30 mg/kg/day for 14 days). Using Western blot analysis, we replicated our previous findings of baseline strain differences and found lower levels of ΔFosB immunoreactivity in NAc of F344 vs. LEW rats. F344 rats showed greater baseline locomotor activity, sniffing, and grooming compared to LEW rats. Chronic cocaine increased ΔFosB levels in NAc in both strains, whereas adaptations in other proteins were induced in F344 rats only. These included reduced levels of tyrosine hydroxylase (TH) in NAc and increased TH and glial fibrillary acidic protein (GFAP) immunoreactivity in VTA. Chronic cocaine led to greater increases in overall stereotypy in F344 vs. LEW rats and decreased exploratory behaviors in LEW rats. Opposing effects by strain were seen in locomotor activity. Whereas F344 rats showed higher initial activity levels that decreased with cocaine exposure (tolerance), LEW rats showed increased activity over days (sensitization) with no strain differences seen at 14 days. Further, conditioned locomotor activation to vehicle injections was greater in F344 vs. LEW rats. These results suggest that behavioral responsiveness to chronic cocaine exposure may reflect dynamics of mesolimbic dopamine protein levels and demonstrate the role of genetic background in responsiveness to cocaine. Synapse 41:179–190, 2001. © 2001 Wiley‐Liss, Inc.
Morphine acutely and persistently attenuates nonvesicular GABA release in rat nucleus accumbens
Authors: Schoffelmeer Anton N.M. , Wardeh George , Vanderschuren Louk J.M.J. 
Published: August 2002

AbstractWithdrawal from repeated exposure to morphine causes a long‐lasting increase in the reactivity of nucleus accumbens nerve terminals towards excitation. The resulting increase in action potential‐induced exocytotic release of neurotransmitters, associated with behavioral sensitization, is thought to contribute to its addictive properties. We recently showed that activation of N‐methyl‐D‐aspartate (NMDA) as well as dopamine (DA) D1 receptors in rat striatum causes tetrodotoxin‐insensitive transporter‐dependent GABA release. Since sustained changes in extracellular GABA levels may play a role in drug‐induced neuronal hyperresponsiveness, we examined the acute and long‐lasting effect of morphine on this nonvesicular GABA release in rat nucleus accumbens slices. The present study shows that morphine, through activation of μ‐opioid receptors, reduces nonvesicular NMDA‐induced [3H]GABA release in superfused nucleus accumbens slices. Moreover, prior repeated morphine treatment of rats (10 mg/kg, sc, 14 days) caused a reduction in NMDA‐stimulated [3H]GABA release in vitro until at least 3 weeks after morphine withdrawal. This persistent neuroadaptive effect was not observed studying dopamine D1 receptor‐mediated [3H]GABA release in nucleus accumbens slices. Moreover, this phenomenon appeared to be absent in slices of the caudate putamen. Interestingly, even a single exposure of rats to morphine (>2 mg/kg) caused a long‐lasting inhibition of NMDA‐induced release of GABA in nucleus accumbens slices. These data suggest that a reduction in nonvesicular GABA release within the nucleus accumbens, by enhancing the excitability of input and output neurons of this brain region, may contribute to the acute and persistently enhanced exocytotic release of neurotransmitters from nucleus accumbens neurons in morphine‐exposed rats. Synapse 42:87–94, 2001. © 2001 Wiley‐Liss, Inc.
Theoretical framework for the continuous early validation (CEaVa) method
Authors: Larsen Robert F. , Buede Dennis M. 
Published: August 2002

AbstractSystems being developed today make extensive and complex use of advanced technology. Many, if not most, of these systems are being produced but are not used or useful on delivery because the wrong problem was solved. A major cause for this shortfall in system development is due to changes in the operational environment of the intended system while the development process is ongoing. Significant sections of the literature discuss the need to get stakeholders involved earlier in the development process to correct this problem. However, no one has developed a detailed framework that accomplishes this intent. This paper defines a method involving a four‐step sequence that validates the entire system design process early and continuously to ensure that the right problem is being solved. The method is called Continuous Early Validation (CEaVa). It is a method that increases the likelihood of producing the correct system. The method develops visibility of potential disconnects among stakeholders' needs, original written requirements, organizational policy, and derived requirements. The CEaVa method validates the external and internal consistency of the problem statement. Additionally, CEaVa facilitates consensus on trade offs and priorities, resolving the potential disconnects with decision analytical reasoning for trade‐off analysis. The CEaVa method improves the development process and ultimately the system itself by increasing the likelihood of building the right system within budget and schedule. © 2002 Wiley Periodicals, Inc. Syst Eng 5: 223–241, 2002