bluuebunny/crossref_metadata_2025 huggingface dataset:
Oseen Flow Past a Finite Flat Plate
Authors: Seebass Richard , Tamada Kô , Miyagi Tosio
Published: December 2004

New results for the viscous incompressible flow past a finite flat plate aligned with the flow are obtained under the Oseen approximation. Results for moderate and large values of the Reynolds number are obtained by means of the Wiener-Hopf technique. For small and moderate values of the Reynolds number, the results are obtained by extending the classical series from four terms to up to one hundred terms. These two schemes have a common region of validity, and thus the results may be interpreted as providing the flow for all Reynolds numbers. The classical result of Piercy and Winny for large Reynolds numbers is found to be in error in the neighborhood of the trailing edge.
Statistical Approach to Flow through Porous Media
Authors: Aranow R. H.
Published: December 2004

Some of the problems are discussed which arise in the application to flow in porous media of the Bearman-Kirkwood theory of transport in fluids. The outstanding feature of porous media is their lack of isotropy on the microscale. The Bearman-Kirkwood analysis is reconsidered for anisotropic systems. The effect of the anisotropic pair-correlation function on the momentum balance equation is considered. Modifications to the nonequilibrium perturbation of the pair-correlation function are considered which lead to tensorial transport coefficients. The averages for the statistically isotropic porous medium which lead to Darcy's law are developed. Some additional problems are considered such as appropriate macroaverages for thermodynamic quantities. The theory rests on an assumed form for the nonequilibrium distribution function. This form awaits theoretical justification.
Ground-State Density Matrices of Quantum Fluids
Authors: Garrod Claude
Published: December 2004

It is shown that important simplifications can be made in a variational calculation of the ground-state two-particle density matrix of an N-particle system if the system is translation-invariant.
Measurements of the Charged Particles of an Equilibrium Turbulent Plasma
Authors: Guthart H. , Weissman D. E. , Morita T.
Published: December 2004

A pair of diagnostic techniques for the measurement of the statistical properties of the ionized particles of an equilibrium turbulent plasma have been developed including an electrostatic probe and a high-resolution microwave probe. The turbulent plasma is formed by seeding a premixed ethylene-oxygen flame in a combustion chamber and then exhausting through an expansion nozzle into a low-pressure vessel. The power spectral density of the fluctuations of the electrons and ions is measured. The electron and ion fluctuations are observed to have the identical spectrum. The ion density correlations in space and space-time have been measured throughout the plasma volume. The distribution of the mean and rms values of the electron density throughout the volume is also presented. It is concluded that on the axis of the hot jet exhaust the turbulent eddy pattern is approximately isotropic and frozen.
Three-Dimensional Normal Modes of a Magnetized Vlasov Plasma
Authors: McCune J. E.
Published: December 2004

The three-dimensional velocity-space eigenmodes of the linearized Vlasov equation for an electronic plasma, imbedded in a uniform applied magnetic field, are derived in the electrostatic limit and are shown to be complete. In general, a continuum of modes exists (except for k · B0 = 0) and, if the plasma is unstable, an additional set of discrete modes appears. It is found that a particular functional of the undisturbed distribution function plays a role (for k · B0 ≠ 0) analogous to Case's η(v) in establishing the properties of the modes. For the case k · B0 = 0, which must be treated separately, two discrete sets of modes exist, only one of which contributes to the density and field fluctuations in the electrostatic approximation.
Observation of Collisionless Electron Heating by Ion Cyclotron Waves
Authors: Yoshikawa S. , Yamato H.
Published: December 2004

Electron heating is observed on application of the ion cyclotron wave in the C stellarator. The observed heating rate is an increasing function of the electron heating, suggesting that the heating is not due to the simple collisional process. The observed heating rate is consistent with the theoretical heating rate due to Landau damping of the wave by the resonant electrons. The generation of a dc electric current was observed when the wave was allowed to propagate in one direction, suggesting that the momentum of the wave is transmitted to electrons by Landau damping. The quasi-linear treatment of the current generation is compared with the observed current generation.
Confinement of a Cesium Plasma in a Mirror Field
Authors: D'Angelo N. , Goeler S. V.
Published: December 2004

Confinement of a thermally-ionized cesium plasma has been investigated in a magnetic mirror geometry. The mirror ratio R has been varied continuously between 1 and 5.7. The observed confinement of the plasma can be accounted for in terms of resistive diffusion and ion recombination at the end plates of the Q device. ``Bohm'' diffusion appears to be inoperative in the conditions of the experiment.
Effect of a Time-Varying Transverse Magnetic Field on the Equilibrium of a Toroidal Plasma
Authors: Kessler John O. , Sinclair Rolf M.
Published: December 2004

Experiments are described in which a localized magnetic field BT(t) could be suddenly applied transverse to the main plane of the C stellarator. Under optimum conditions the plasma temperatures and decay times were similar to those obtained by conventional means. The field BT(t) was used to demonstrate that a sudden change in the plasma equilibrium conditions is directly correlated with sudden changes of the plasma impedance. An explanation of this phenomenon in terms of macroscopic drift motions of the plasma is suggested.
Observations on the Velocity of Moving Striations
Authors: Alexeff I. , Jones W. D.
Published: December 2004

At very low gas pressures the observed striation velocity is approximately equal to the ionic-sound-wave velocity of Tonks and Langmuir. At higher pressures it decreases with increasing pressure. As very low pressure is approached, the striations abruptly reverse their direction of propagation.
Molecular origins of rapid and continuous morphological evolution
Authors: Fondon John W. , Garner Harold R.
Published: December 2004

Mutations in cis-regulatory sequences have been implicated as being the predominant source of variation in morphological evolution. We offer a hypothesis that gene-associated tandem repeat expansions and contractions are a major source of phenotypic variation in evolution. Here, we describe a comparative genomic study of repetitive elements in developmental genes of 92 breeds of dogs. We find evidence for selection for divergence at coding repeat loci in the form of both elevated purity and extensive length polymorphism among different breeds. Variations in the number of repeats in the coding regions of the
Alx-4
(aristaless-like 4) and
Runx-2
(runt-related transcription factor 2) genes were quantitatively associated with significant differences in limb and skull morphology. We identified similar repeat length variation in the coding repeats of
Runx-2
,
Twist
, and
Dlx-2
in several other species. The high frequency and incremental effects of repeat length mutations provide molecular explanations for swift, yet topologically conservative morphological evolution.
Application of Gene Expression Profiling for Validating Models of Human Breast Cancer
Authors: Green Jeffrey E. , Desai Kartiki V. , Yumei Ye  , Kavanaugh Claudine , Calvo Alfonso , Huh Jung-Im
Published: December 2004

While classical histopathologic approaches are invaluable in classifying tumors and understanding aspects of cellular interactions, genomic approaches provide a means to molecularly dissect tumorigenesis. The relationship of gene expression to the development of neoplasia remains an area of intensive research. With the advent of large-scale genomic platforms, alterations in gene expression can be related to the morphological development of cancer. The feasibility of using large-scale genomic analysis platforms has dramatically changed the landscape of biological sciences, as cellular processes must be considered in the context of complex networks. Alterations in gene expression must now be understood in a systems approach in which the relationships between genes expression changes are studied by considering the interplay of multiple regulatory networks. Ultimately, such changes must be understood at the protein level. We have begun to apply this technology to determine changes in gene expression that differentiate various types of mammary cancers that arise in mouse models that have been initiated by different genetic alterations. Ultimately, a molecular catalogue of similarities and differences between rodent and human tumors can be created which will serve to validate or credential particular models for specific experimental purposes, such as preclinical testing. These approaches have led to new insights into molecular pathways involved in oncogenesis, new classifications of human breast cancer, and the identification of new genes that may be relevant to understanding and treating human cancer.
Making Mechanistic Connections between Cell Signaling Pathways and Pathological Endpoints
Authors: Davis Myrtle A.
Published: December 2004

Cell signaling is a term used to describe a complex interactive system of signals that act to regulate or mediate a cellular response. Therapies that target cell signaling pathways have the potential to effectively reverse molecular deregulation underlying disease. The inherent complexity of cell signaling presents a major challenge to designing such therapies however, because perturbation of pathways has the potential to produce dramatic adverse effects. Pathologists are in the primary position of detecting adverse responses in drug development and are essential members of teams whose goal is to determine the mechanisms underlying tissue responses. The pathologist therefore will be expected to integrate morphologic interpretation with data obtained from several laboratory-based methods and data derived from novel technologies. Approaches being used include several in silico tools that provide access to public databases and signal pathway visualization that can serve to focus on key mechanistic hypotheses. The main objective of this article is to discuss a basic mechanistic approach and methods that can be used to associate modulation of cell signaling pathways with pathologic endpoints. The approach suggested begins with diagnostic pathology and uses global gene expression analysis in conjunction with transcription factor profiling and confirmatory protein technologies, to elucidate pathways relevant to the biological mechanism. Another important objective is to highlight the use of in silico technologies to prioritize laboratory efforts and focus these efforts on key hypotheses.
The Intrathymic Pathogenesis of Myasthenia Gravis
Authors: Levinson Arnold I. , Song Decheng , Gaulton Glen , Zheng Yi
Published: December 2004

The thymus is considered to play an important role in the pathogenesis of Myasthenia gravis, an autoimmune disease characterized by antibody‐mediated skeletal muscle weakness. However, its role is yet to be defined. The studies described herein summarize our efforts to determine how intrathymic expression of the neuromuscular type of acetylcholine (ACh) receptors is involved in the immunopathogenesis of this autoimmune disease. We review the work characterizing the expression of neuromuscular ACh receptors in the thymus and advance a new hypothesis that examines the intrathymic expression of this autoantigen in disease pathogenesis.
The Undershoot Bias
Authors: Engelbrecht Sascha E. , Berthier Neil E. , O'Sullivan Laura P.
Published: December 2004

Learning in stochastic environments is increasingly viewed as an important psychological ability. To extend these results from a perceptual to a motor domain, we tested whether participants could learn to solve a stochastic minimal-time task using exploratory learning. The task involved moving a cursor on a computer screen to a target. We systematically varied the degree of random error in movement in three different conditions; each condition had a distinct time-optimal solution. We found that participants approximated the optimal solutions with practice. The results show that adults are sensitive to the stochastic structure of a task and naturally adjust the magnitude of an undershoot bias to the particular movement error of a task.
Attentional Enhancement Opposite a Peripheral Flash Revealed Using Change Blindness
Authors: Tse P.U. , Sheinberg D.L. , Logothetis N.K.
Published: December 2004

We describe a new method for mapping spatial attention that reveals a pooling of attention in the hemifield opposite a peripheral flash. Our method exploits the fact that a brief full-field blank can interfere with the detection of changes in a scene that occur during the blank. Attending to the location of a change, however, can overcome this change blindness, so that changes are detected. The likelihood of detecting a new element in a scene therefore provides a measure of the occurrence of attention at that element's location. Using this measure, we mapped how attention changes in response to a task-irrelevant peripheral cue. Under conditions of visual fixation, change detection was above chance across the entire visual area tested. In addition, a “hot spot” of attention (corresponding to near-perfect change detection) elongated along the cue-fixation axis, such that performance improved not only at the cued location but also in the opposite hemifield.
Writing is more than ‘exciting’: equipping primary children to become reflective writers
Authors: Corden Roy
Published: December 2004

This article describes work undertaken as part of a partnership programme initiated to encourage collaborative research between teachers and university tutors. In the Teaching Reading and Writing Links project (TRAWL) primary school teachers, working as research partners, explored ways of developing children as reflective writers. The research group wanted to know whether, through examining how texts are crafted by expert writers during literacy sessions, children might be encouraged to pay more attention to compositional rather than secretarial aspects of narrative writing during writing workshops. The overall writing achievement of 338 children was monitored over one school year and narrative writing from 60 case study children was evaluated at the beginning and end of the research period. In this article the impact on achievement is illustrated, some examples of writing are analysed and evidence of development in children's metacognition and confidence as writers is discussed.
Book Reviews
Authors: Mucklow Fiona
Published: December 2004

Books reviewed:

Laurence Boisson de Chazournes and Philippe Sands (eds), Reflections on International Law, the International Court of Justice and Nuclear Weapons

Christopher C. Joyner, Governing the Frozen Commons – The Antarctic Regime and Environmental Protection

Ian H. Rowlands (ed), Climate Change Cooperation in Southern Africa

Theodore Panayotou, Instruments for Change, Motivating and Financing Sustainable Development

Jonathan Krueger, International Trade and the Basel Convention
Licensing of New Technology Versus Direct Foreign Investment: A General Equilibrium Analysis
Authors: Miyagiwa Kaz , Young Leslie
Published: December 2004

In a general equilibrium model with sector‐specific capital, a country which licenses new technology and imports capital itself would have lower national income than if it permitted direct investment by foreigners with rights to the technology. However, the reverse can be true if capital is mobile between sectors. Thus, licensing is a poor policy in the short run but can be a good policy in the long run.
Boundary mechanisms and symbolic resources: towards a process‐oriented approach to national identity*
Authors: Zimmer Oliver
Published: December 2004

This article argues that the classical distinction between civic and ethnic forms of national identity has proved too schematic to come to terms with the dynamic nature of social and political processes. This has caused difficulties particularly for those historians and social scientists studying particular national movements rather than concentrating on a handful of thinkers and intellectuals or taking a broadly comparative approach. As an alternative to the classical model, I propose to distinguish between, on the one hand, the mechanisms which social actors use as they reconstruct the boundaries of national identity at a particular point in time; and, on the other, the symbolic resources upon which they draw when they reconstruct these boundaries.
Repetition and semantic priming of nonwords: Implications for theories of N400 and word recognition
Authors: Deacon Diana , Dynowska Anna , Ritter Walter , Grose‐Fifer Jillian
Published: December 2004

ERPs were elicited by two types of orthographically legal, pronounceable nonwords. One nonword set was derived from and resembled real words, whereas the other set did not. Nonwords derived from related root words elicited N400 semantic priming effects similar to those obtained for words, indicating semantic activation of the root words. N400 repetition priming effects from nonderived nonwords were similar to those obtained for words. The elicitation of N400 by only derived nonwords would have suggested it was generated by the activation of word meanings, per se. However, both types of nonwords produced an N400, and an N400 priming effect. Because nonderived nonwords are not associated with meaning, the N400 cannot be generated by semantic activation per se. Rather, the N400 appears to be generated by orthographic/phonological analysis and is attenuated by the top‐down feed of semantic information to the orthographic/phonological level.
Stimulus context determines P3a and P3b
Authors: Katayama Jun'ichi , Polich John
Published: December 2004

P300 differences for target (.10), nontarget (.10), and standard tones (.80) were assessed using a three‐stimulus oddball paradigm in which participants responded only to the target (n= 12). Target/standard (easy or difficult) and nontarget/standard (large or small) pitch differences were manipulated orthogonally. In all conditions, target tones elicited a parietal P300, which was affected only by the target/standard discrimination ease. Nontarget in the easy/large and difficult/small conditions elicited a parietal but smaller P300 than the target but in the easy/small condition elicited similar ERPs to the standard. However, nontarget stimuli in the difficult/large condition elicited an anterior maximum and earlier P300 (P3a) component. The findings suggest that target P300s are not influenced by the nontarget stimulus configuration, whereas the nontarget P300 outcomes are determined directly by the stimulus context. The theoretical implications are discussed.
Cortical control of human classical conditioning: Autonomic and positron emission tomography data
Authors: Hugdahl Kenneth
Published: December 2004

A recent positron emission tomography (PET) study on brain mechanisms in classical, or Pavlovian, conditioning is reviewed. The PET data were compared with skin conductance data recorded off‐line. The participants were five men who participated in three different experimental phases. In the first (habituation) phase, a tone was repeated 24 times at random intervals. In the second (acquisition) phase, the tone was paired with a brief shock to the wrist. In the third (extinction) phase, the tone was presented alone again. Statistical parametric mapping analysis of the PET data showed significantly increased activation of the right hemisphere in the orbitofrontal cortex, dorsolateral prefrontal cortex, inferior and superior frontal cortices, and inferior and middle temporal cortices. In the left hemisphere, only Area 19 and the superior frontal cortex showed significant activation. The findings are discussed within a theoretical framework that argues for different brain mechanisms in acquisition and extinction in classical conditioning.
The effects of stimulus intensity and age on visual‐evoked potentials (VEPs) in normal children
Authors: Carrillo‐de‐la‐Peña M. , Holguín S. Rodríguez , Corral M. , Cadaveira F.
Published: December 2004

In this study, we explored the effects of flash intensity and age on visual‐evoked potentials (VEPs) in a sample of 85 children aged 8–15 years. Results of previous studies are discrepant regarding the extent to which children show an evoked potential augmenting tendency at vertex, which has been reported to be a characteristic of an immature inhibitory control system. In the present study, VEPs to light flashes of four different intensities were recorded at Cz. The results confirmed that P1N1 and N1P2 at Cz were positively related to increases in stimulus intensity, whereas N1 was not related reliably to intensity. This difference between peak–peak and baseline–peak amplitude findings at Cz relative to evoked potential augmenting and reducing may help to explain discrepant results among earlier studies. Developmental changes were found for our sample of children that were independent of stimulus intensity: N1 amplitude increased significantly with age, whereas N1 latency showed a small (nonsignificant) age‐related decrease.
Editorial
Authors: Miller Gregory A.
Published: December 2004

In 1960, the newly founded Society for Psychophysiological Research captured the already considerable breadth of the just‐forming field of psychophysiology. The Society began publishing Psychophysiology in 1964 with the mandate to address that breadth. As the field has grown rather enormously in the past 40 years, the journal has expanded accordingly. Whole new (and still overlapping) fields such as behavioral medicine have taken root, and new technologies such as hemodynamic brain imaging continue to enrich the psychophysiologist's toolbox. Beyond important domains of clinical, developmental, and human‐factors application and exciting methodological developments, psychophysiology has made great progress on basic substantive questions such as the relationship of fundamental reflexes to emotional behavior and the role of regional brain specialization in perceptual and cognitive function. In so doing, the field has necessarily faced up to conceptual challenges such as what is involved in manipulating emotion in the laboratory and in verifying the manipulation.
For Distinguished Contributions to Psychophysiology: Steven A. Hillyard
Authors: Näätänen Risto
Published: December 2004

At the Thirty‐Ninth Annual Meeting of the Society for Psychophysiological Research (SPR), the award for Distinguished Contributions to Psychophysiology was presented to Steven A. Hillyard. The following is the citation given by Risto Näätänen on behalf of the Society's Awards Committee on October 9, 1999.
Preparation of response force and movement direction: Onset effects on the lateralized readiness potential
Authors: Müller‐Gethmann Hiltraut , Rinkenauer Gerhard , Stahl Jutta , Ulrich Rolf
Published: December 2004

Two experiments assessed the preparatory effects of advance information about response force and movement direction on the lateralized readiness potential (LRP). In a choice reaction time (RT) task, an imperative stimulus required an isometric flexion or an extension of the left or right index finger. Prior information about response force or about movement direction reduced RT and shortened the interval from the onset of the imperative stimulus up to the onset of the LRP. Advance information, however, about direction but not about force decreased the interval from LRP onset to the onset of the overt response. The identical pattern of results was obtained in a second experiment, in which each participant performed both precue conditions. The findings of both experiments support the notion that response force is specified before movement direction. These results are consistent with the view accordingly different mechanisms are involved in the specification of muscle force and movement direction.
Enhancing the laboratory‐to‐life generalizability of cardiovascular reactivity using multiple occasions of measurement
Authors: Kamarck Thomas W. , Debski Thomas T. , Manuck Stephen B.
Published: December 2004

Studies examining the association between laboratory measures of stress‐related cardiovascular (CV) reactivity and responses to psychological challenges in the natural environment have yielded mixed results. Frequently, single laboratory tasks have been used to predict responses to natural stressors on a single occasion of measurement. Because aggregation broadens the range of stimuli sampled and reduces measurement error, laboratory‐to‐life generalizability should be more easily detected when multiple predictor and criterion observations are used. Sixty students in a public speaking course were administered multitask assessments of CV reactivity during two laboratory sessions and during two in‐class public speech assignments. CV responses to the classroom speeches were greater among those who showed larger responses in the laboratory, and these associations became stronger as measures were aggregated across multiple samples of behavior. These results support the generalizability of CV reactivity as a measure of individual difference, and they help to shed light on previous inconsistent findings in this area.
Selective inhibition is indexed by heart rate slowing
Authors: van der Veen Frederik M. , van der Molen Maurits W. , Jennings J. Richard
Published: December 2004

This study examined the hypothesis that global and selective inhibition are mediated by distinct mechanisms: respectively, a peripheral mechanism, indexed by heart rate slowing, and a central mechanism, indexed by cortical but not autonomic measures. Three varieties of a Go‐NoGo task were presented in which the Go signal required an index finger response rapidly followed by a middle finger response. The NoGo signal required the inhibition of (a) both responses (global inhibition), (b) the middle finger response (simple selective inhibition), or (c) the index finger response of one hand and the middle finger response of the other hand (complex selective inhibition). As anticipated, global inhibition was indexed by heart rate slowing. Most importantly, heart rate slowing was also elicited by selective inhibition and was more pronounced for complex than simple selective inhibition. These findings suggest that global and selective inhibition are mediated by one rather than two mechanisms and that heart rate is sensitive to the demands placed on this inhibition mechanism.
Developmental change in auditory selective attention as reflected by phasic heart rate changes
Authors: van der Molen Maurits W. , Somsen Riek J.M. , Jennings J. Richard
Published: December 2004

Heart rate was recorded from five different groups of children (ages 7, 10, 12, 14, and 20 years) while they were performing an auditory selective attention task. The participants were instructed to count rare tone pips embedded in a series of standard tone pips presented at one (attended) ear while ignoring rare and standard stimuli presented at the other (unattended) ear. A pattern of anticipatory heart rate deceleration followed by acceleration was associated with rare tone pips at the attended ear but not with rare tone pips that should be ignored. The absence of differential sensitivity of heart rate responses to rare tone pips presented at the unattended ear was observed for all age groups. These findings were interpreted to suggest that the ability to ignore irrelevant target stimuli has reached mature levels during middle childhood. The depth of anticipatory deceleration increased until age 14, suggesting that the ability to maintain attentional set continues to develop beyond childhood.
Right N170 modulation in a face discrimination task: An account for categorical perception of familiar faces
Authors: Campanella S. , Hanoteau C. , Dépy D. , Rossion B. , Bruyer R. , Crommelinck M. , Guérit J.M.
Published: December 2004

Behavioral studies have shown that two different morphed faces belonging to the same identity are harder to discriminate than two faces stemming from two different identities. The temporal course of this categorical perception effect has been explored through event‐related potentials. Three kinds of pairs were presented in a matching task: (1) two different morphed faces representing the same identity (within), (2) two other faces representing two different identities (between), and (3) two identical morphed faces (same). Following the second face onset in the pair, the amplitude of the right occipitotemporal negativity (N170) was reduced for within and same pairs as compared with between pairs, suggesting an identity priming effect. We also observed a modulation of the P3b wave, as the amplitude of the responses for within pairs was higher than for between and same pairs, suggesting a higher complexity of the task for within pairs. These results indicate that categorical perception of human faces has a perceptual origin in the right occipitotemporal hemisphere.
The relationship between prepulse detection and prepulse inhibition of the acoustic startle reflex
Authors: Postma Peggy , Kumari Veena , Hines Melissa , Gray Jeffrey A.
Published: December 2004

Prepulse inhibition (PPI) of the startle reflex is defined as the attenuation of the startle response to a startling stimulus (pulse), when such a stimulus is briefly preceded by a stimulus of subthreshold intensity (prepulse). PPI is thought to be neither learned nor due to conscious response inhibition, as it occurs at stimulus onset asynchronies (SOAs) too short to enable the activation of a volitional response. The present study explored the latter of these assertions by investigating (a) the degree to which human subjects are able to detect prepulses at SOAs of 30, 60 and 120 ms, and (b) whether such detection is related to inhibition. Startle eyeblink reflex and detection were measured in 39 participants subjected to an acoustic startle paradigm. Results revealed a significant trend in prepulse detection according to SOA, with highest detection rates at the 120‐ms SOA (75%). However, trials on which detection occurred did not differ from trials without detection on measures of startle inhibition. This suggests that PPI is independent of awareness of the prepulse.
Adrenocortical stress responses and altered working memory performance
Authors: Al'Absi Mustafa , Hugdahl Kenneth , Lovallo William R.
Published: December 2004

This study examined stress cortisol responses and cognitive performance. We initially measured cortisol responses of 40 right‐handed healthy male volunteers to counterbalanced mental arithmetic and public speaking stressors. We then examined the relationship between cortisol reactivity and dichotic listening and mental arithmetic performance. High cortisol responders made more errors and completed fewer mental arithmetic items than low reactors. On dichotic listening, high responders tended toward better performance in all conditions and to both ears. High responders showed better performance to the right ear in the forced right than in the nonforced condition, whereas no difference between these conditions was found in low responders. High cortisol responders may have an increased focus on sensory stimuli and a decreased allocation of resources to working memory tasks.
Value of event‐related P300 subcomponents in the clinical diagnosis of mild cognitive impairment and Alzheimer's Disease
Authors: Frodl Thomas , Hampel Harald , Juckel Georg , Bürger Katharina , Padberg Frank , Engel Rolf R. , Möller Hans‐jürgen , Hegerl Ulrich
Published: December 2004

Accurate and early diagnosis of Alzheimer's Disease (AD) with reliable and noninvasive methods is of great importance for clinical practice as effective and specific antidementive therapies become available. The aim of the study was to evaluate the clinical relevance of event‐related P300 in the early diagnosis of AD. Thirty patients with AD, 26 patients with mild cognitive impairment (MCI) from our Memory Clinic and 26 age‐matched healthy controls (HC) were studied with event‐related P300 potentials. Amplitudes of temporo‐basal dipoles (TB‐P300) were significantly diminished in AD compared to HC and MCI. Furthermore, latencies of temporo‐superior dipoles (TS‐P300) were significantly prolonged in AD compared with HC. Sensitivity was 90.0% for the differentiation of patients with AD from HC (specificity 79.1%) using reduced TB‐P300 amplitudes and prolonged TS‐P300 latencies. Similar results were found using Pz amplitudes as well as Fz latencies. Our data suggest that TB‐P300 amplitudes and TS‐P300 latencies may be an accurate clinically available, nonexpensive, noninvasive, and reliable marker for AD.
Contribution of tonic vagal modulation of heart rate, central respiratory drive, respiratory depth, and respiratory frequency to respiratory sinus arrhythmia during mental stress and physical exercise
Authors: Houtveen Jan H. , Rietveld Simon , de Geus Eco J.C.
Published: December 2004

This study tested various sources of changes in respiratory sinus arrhythmia (RSA). Twenty‐two healthy participants participated in three experimental conditions (mental stress, relaxation, and mild physical exercise) that each consisted of three breathing parts (normal breathing, breathing compressed room air, and breathing compressed 5% CO2‐enriched air). Independent contributions to changes in RSA were found for changes in tonic vagal modulation of heart rate, central respiratory drive (i.e., PaCO2), respiratory depth, and respiratory frequency. The relative contributions to changes in RSA differed for mental stress and physical exercise. It is concluded that uncorrected RSA will suffice to index within‐subject changes in tonic vagal modulation of heart rate in most situations. However, if the central respiratory drive is expected to change, RSA should ideally be corrected for changes in PaCO2, respiratory depth, and respiratory frequency.
Exaggeration of blood pressure‐related hypoalgesia and reduction of blood pressure with low frequency transcutaneous electrical nerve stimulation
Authors: Campbell Tavis S. , Ditto Blaine
Published: December 2004

Reduced pain perception has been observed in hypertensive individuals and normotensive individuals at risk for high blood pressure and may involve increased endogenous opioid release or receptor sensitivity. The present study examined the issue by administering two subjectively similar but physiologically different forms of the pain‐reducing procedure transcutaneous electrical nerve stimulation (TENS). Men varying in resting blood pressure and parental history of hypertension participated in three testing sessions during which was presented (a) high‐frequency (100 Hz) TENS; (b) low‐frequency (2 Hz) TENS, the type believed to elicit endogenous opioid activity; or (c) no‐TENS stimulation. Measurements of blood pressure (BP) and other physiological variables were obtained during this period. Afterwards, two pain stimuli were presented: a series of electric shocks and 5 min of arm ischemia. There was a significant negative association between pain and resting systolic blood pressure (SBP), and pain and parental history of hypertension in the no‐TENS and high‐frequency TENS conditions that was significantly strengthened by administration of low‐frequency TENS. As well, low‐frequency TENS produced a modest but significant acute reduction in SBP, especially among those with higher resting levels. These results provide further evidence that opioid mechanisms are involved in blood pressure‐related hypoalgesia and blood pressure regulation.
Deficits in automatically detecting changes in conjunction of auditory features in patients with schizophrenia
Authors: Alain Claude , Bernstein Lori J. , Cortese Filomeno , Yu He , Zipursky Robert B.
Published: December 2004

Disturbances in processing simple acoustic changes in a stream of stimuli have been widely reported in patients with schizophrenia, but little is know about auditory feature conjunction in these individuals. This study was designed to examine the extent to which patients with schizophrenia automatically process changes in conjunction of auditory features by using event‐related brain potentials. Seventeen patients and 17 age‐matched controls were presented with frequent low pitch tones at 45° to the left of center and frequent high pitch tones at 45° to the right of center while performing a continuous visual serial‐choice reaction time task. The sequence of auditory stimuli included rare conjunction‐deviants comprised of a different combination of features (e.g., low pitch tone at 45° right) and double‐deviant tones that differed from the standard tones in both pitch and location (i.e., middle pitch at 0° azimuth). Conjunction‐deviant stimuli elicited an MMN wave that was maximum at frontocentral sites. Compared with controls, the MMN to conjunction‐deviant was reduced in patients and was more centrally distributed. Double‐deviant sounds generated a biphasic MMN followed by a P3a wave at central sites. Both MMN and P3a were reduced in patients compared with controls. These results show that patients with schizophrenia have difficulty in automatically detecting changes in a combination of auditory features as well as orienting to what “normally” would be considered salient by healthy individuals.
The impact of reinforcement density on response differentiation in configural discrimination problems
Authors: Lachnit Harald , Lober Klaus , Reinhard Günter , Giurfa Martin
Published: December 2004

Two human Pavlovian conditioning experiments investigated the impact of reinforcement density (the number of reinforced trials divided by the total number of trials) on discrimination learning. Experiment 1 used a negative patterning problem (A+, B+, AB−) and Experiment 2 used a positive patterning problem (A−, B−, AB+). In both experiments, reinforcement density varied across four levels. Response differentiation between reinforced and nonreinforced stimuli was linearly related to the decrease in reinforcement density. Responses to nonreinforced stimuli did not differ between the four groups in either experiment. In contrast to this, responses to reinforced stimuli were considerably more pronounced in conditions with lower reinforcement density. For negative patterning, this replicates and extends similar observations from other species. For positive patterning, this is a finding that has not yet been reported in other experiments. The results are in agreement with the comparator hypothesis (Miller & Matzel, 1988) and with Wagner's (1981) “standard operating procedures” (SOP) model.
Effects of musical expertise on the early right anterior negativity: An event‐related brain potential study
Authors: Koelsch Stefan , Schmidt Björn‐helmer , Kansok Julia
Published: December 2004

Event‐related brain potentials in response to harmonically inappropriate chords were compared for musical experts and novices. Similar to previous studies, these chords elicited an early right anterior negativity (ERAN). The amplitude of the ERAN was clearly larger for musical experts than for novices, presumably because experts had more specific musical expectancies than novices. Chords with a physically deviant timbre elicited a mismatch negativity that did not differentiate the groups, indicating that the larger ERAN in experts was not due to a general enhanced auditory sensitivity. The ERAN reflects fast and automatic neural mechanisms that process complex musical (music‐syntactic) irregularities, and the present results indicate that these mechanisms can be modulated by expertise.
Vagal tone as an indicator of treatment response in major depression
Authors: Chambers Andrea S. , Allen John J.B.
Published: December 2004

Increased vagal tone has been associated with treatment success using pharmacological agents and cognitive‐behavioral treatment in major depression, but not using electroconvulsive therapy. The present study investigated whether increases in vagal tone would be associated with favorable treatment response with nonpharmacological treatment. At baseline and following treatment, 16 subjects were administered the Hamilton Rating Scale for Depression (HRSD) followed by electrocardiographic recording. Those with little change in vagal tone from before to after treatment showed minimal reduction in HRSD score (−4.8); those with larger vagal tone change showed a large decrease in HRSD score (−14.8). Changes in vagal tone are thus related to favorable treatment response in depression, and do not represent anticholinergic pharmacological effects. Future work manipulating vagal tone might prove informative in teasing apart the causal role of vagal tone and depression.
Suspicious minds: The motive to acquire relationship‐threatening information
Authors: Ickes William , Dugosh Jeremy W. , Simpson Jeffry A. , Wilson Carol L.
Published: December 2004

In four studies, we obtained evidence for the reliability and validity of a 21‐item scale designed to measure a new theoretical construct: individual differences in the motivation to acquire relationship‐threatening information (hereafter, MARTI). Study 1 provided evidence for the MARTI scale's reliability and discriminant validity, revealing that it was reliable and not significantly correlated with measures of the Big Five personality traits, adult attachment styles, or more general social orientations. Studies 2 and 3 provided evidence for the scale's convergent and discriminant validity, showing that dating partners with higher MARTI scores (i.e., those who were more motivated to acquire relationship‐threatening information) scored lower in relational trust and reported engaging in more “suspicion behaviors.” Study 4 provided behavioral evidence for the scale's predictive validity, revealing that (a) dating partners with higher MARTI scores were more likely to break up within 5 months, and (b) the breakup rate was most pronounced for dating partners who scored higher on the scale and who also reported being less close. We discuss how this new construct and measure can be used to study important relationship dynamics.

We can’t go on together

With suspicious minds.

‐ Lines from the 1969 Elvis Presley hit
Social capital, social currency, and portable assets: The impact of residential mobility on exchanges of social support
Authors: Magdol Lynn , Bessel Diane R.
Published: December 2004

We examined the impact of physical distance on mobilized social capital resources. Social capital theory assumes that physical proximity and residential stability are prerequisites to social capital assets. We tested these assumptions using a two‐wave panel sample from the National Survey of Families and Households consisting of respondents who experienced residential moves between waves. We found local duration since the last move to be beneficial for involvement in social exchanges. Mobility distance was related to deficits for some exchanges but not for others. Rather than a simple dichotomy between material resources that require proximity and nonmaterial resources that do not, we found that emotional and financial support are not affected by mobility distance but that tangible favors and companionship are affected negatively. Although kin exchanges are negatively affected by distant and recent mobility, nonkin exchanges are more extensive for respondents whose kin ties are more distant, suggesting a process of substitutability whereby nonkin may replace kin in the network. Our findings confirm the assumption of social capital theory about distance. They also point to the importance of adding the dimension of distance to exchange theory. Our study demonstrates that place has not lost all relevance in our highly technological postmodern society.
We were the Trojans: British national identities in 1633
Authors: Hopkins Lisa
Published: December 2004

In 1633, several significant works of literature were published for the first time. These included Spenser's A View of the Present State of Ireland, Jasper Fisher's Fvimus Troes, George Wither's Iwenilia, Charles Aleyn's The Battailes of Crescey and Poictiers, while John Ford's Perkins Warbeck, though not published until 1634, was probably first performed in 1633. In the same year, Charles I rode north to his Scottish coronation, calling forth the celebratory poem Scotland's Welcome by William Lithgow, and Ben Jonson also wrote The King's Entertainment at Welbeck to entertain the king when he broke his journey at the earl of Newcastle's great house, Welbeck Abbey in Nottinghamshire. The year also saw the appointment of Strafford as Lord Deputy in Ireland, Thomas Stafford's Pacata Hibernica, and Geoffrey Keating's History of Ireland, and the centenary of Henry VIII's first declaration of England as an empire in 1533. This essay argues that these events and publications are linked by their concern with questions of what it meant to be English, Scottish, Irish, or Anglo‐Irish, with the occasion of Charles I's Scottish coronation, coupled with his growing political unpopularity, provoking a collective soul‐searching on the subject of national identities.
Lorenzo de' Medici's new men and their mores: the changing lifestyle of Quattrocento Florence
Authors: Brown Alison
Published: December 2004

As an approach to the contentious problem of how to define the nature of Florentine society – feudal or mercantile, old or new – this paper investigates the outlook and lifestyle of Lorenzo de' Medici's secretary‐notaries, a new and highly vocal group of functionaries in the later fifteenth century. It examines first their social behaviour, especially their clothes and consumerism, then their political role and ambitions, and finally their morality, arguing that these men sought to rise in society by adopting ‘new ways’ and attitudes, not those of the old elite. In doing so, they articulated the outlook and values that came to typify new thinking about politics and society in the early modern period.
A Response to Jeremy Waldron's Law and Disagreement
Authors: North Richard
Published: December 2004

This article offers a critical response to arguments developed by Jeremy Waldron on the subject of democracy and constitutional rights. In particular it responds to three claims made by Waldron: first, he claims contemporary Western societies are characterised by deep and intractable disagreement; second, collectively binding decisions should be reached by democratic means alone; and third constitutional devices, such as bills of rights, should be rejected because they act as constraints on democracy. I argue that Waldron is unable to argue for the primacy of democracy from the baseline of intractable disagreement that he posit. He implicitly relies upon a position of moral consensus to confirm the priority of democracy over alternative decision-making procedures. Further, the moral stance that Waldron takes towards democracy is based upon a Kantian theory of justice which is shared by liberal-constitutional theorists, such as Rawls and Dworkin, who advocate bills of rights. Finally, Waldron does not provide the arguments necessary to justify the rejection of bills of rights. Good reasons exist for tempering democratic procedures with constitutional devices. However, this conclusion is qualified. It depends upon counterfactual claims that can be resolved only by taking into account the specific institutional and cultural practices of particular political systems.