bluuebunny/crossref_metadata_2025 huggingface dataset:
Instabilities in a plane channel flow between compliant walls
Authors: DAVIES CHRISTOPHER , CARPENTER PETER W.
Published: July 2002

The stability of plane channel flow between compliant

walls is investigated for disturbances which have the same symmetry,

with respect to the channel centreline,

as the Tollmien–Schlichting mode of instability. The

interconnected behaviour of

flow-induced surface waves and Tollmien–Schlichting waves is examined
both by

direct numerical solution of the Orr–Sommerfeld equation and by means
of an

analytic shear layer theory. We show that when the compliant wall properties
are

selected so as to give a significant stability effect on Tollmien–Schlichting

waves, the onset of divergence instability can be severely disrupted.

In addition, travelling wave flutter can interact with the

Tollmien–Schlichting mode to generate a

powerful instability which replaces the flutter instability identified

in studies based

on a potential mean-flow model. The behaviour found when the mean-flow
shear

layer is fully accounted for may be traced to singularities in the wave
dispersion

relation. These singularities can be attributed to solutions which

represent Tollmien–Schlichting waves in rigid-walled

channels. Such singularities will also be found in

the dispersion relation for the case of Blasius flow. Thus, similar behaviour
can be

anticipated for Blasius flow, including the disruption of the onset

of divergence instability. As a consequence, it seems likely

that previous investigations for Blasius

flow will have yielded very conservative estimates for the optimal stabilization
that

can be achieved for Tollmien–Schlichting waves for the purposes

of laminar-flow control.
An operator expansion formalism for nonlinear surface waves over variable
depth
Authors: SMITH RALPH A.
Published: July 2002

The Hamiltonian formalism for surface waves associated with the
method of Watson
& West (1975) is extended to handle the case of spatially varying bottom
depth.
This description models moderately nonlinear waves over a wider range of
scales
than Boussinesq-type approximations. A pseudospectral simulation code has
been
developed using this formalism in two horizontal dimensions. Computations
using
the model compare well with measurements of waves over a bar, diffractive
focusing
by topography, and shoaling of solitary waves. Waveforms are computed accurately

until near the point of breaking.
Elementary stratified flows with instability at
large Richardson number
Authors: MAJDA ANDREW J. , SHEFTER MICHAEL G.
Published: July 2002

In contrast to the Miles–Howard theorem for inviscid steady
shear flow in stably
stratified fluids, explicit elementary time-periodic solutions of the Boussinesq
equations
are developed here which are unstable for arbitrarily large Richardson
numbers.
These elementary flows are parameterized through solutions of a nonlinear
pendulum
equation and involve spatially constant but temporally varying vorticity
and density
gradients which interact through advection and baroclinic vorticity production.
Exact
nonlinear solutions for arbitrary wave-like disturbances for these flows
are developed
here and Floquet theory combined with elementary numerical calculations
is utilized
to demonstrate instability at all large Richardson numbers. The dominant
inviscid
instability for these non-parallel flows is a purely two-dimensional parametric
instability
with twice the period of the elementary flow and persists for all Reynolds

numbers and the wide range of Prandtl numbers,
1[les ]Pr[les ]200, investigated here.
Similar elementary time-periodic solutions of the Boussinesq equations
in a constant
external strain field are developed here which reduce to uniform shear
flows in one
extreme limit and the time-periodic vortical flows in the other extreme
limit. These
flows are stable in a strict sense for large Richardson numbers; however
there is
transient large-amplitude non-normal behaviour which yields effective instability
for
a wide range of Richardson numbers. For example, suitable initial perturbations

can amplify by at least a factor of fifty with exponential growth for short
times for
[Rscr ]i=1, [mid ]σ[mid ][les ]0.5 and
[Rscr ]i=5, [mid ]σ[mid ][les ]0.1, with σ the amplitude

of the external strain.
The decay of cyclonic eddies by Rossby wave radiation
Authors: McDONALD N. ROBB
Published: July 2002

It is argued that because shallow water cyclones on a
β-plane drift westward at a speed
equal to an available Rossby wave phase speed, they must radiate energy
and cannot,
therefore, be steady. The form of the Rossby wave wake accompanying a quasi-steady

cyclone is calculated and the energy flux in the radiated waves determined.
Further,
an explicit expression for the radiation-induced northward drift of the
cyclone is
obtained. A general method for determining the effects of the radiation
on the radius
and amplitude of the vortex based on conservation of energy and potential
vorticity
is given. An example calculation for a cyclone with a ‘top-hat’

profile is presented,
demonstrating that the primary effect of the radiation is to decrease the
radius of the
vortex. The dimensional timescale associated with the decay of oceanic
vortices is of
the order of several months to a year.
Resonant scattering of edge waves by longshore
periodic topography: finite beach slope
Authors: CHEN YONGZE , GUZA R. T.
Published: July 2002

The resonant scattering of low-mode progressive edge waves by small-amplitude
longshore periodic depth perturbations superposed on a plane beach has recently
been investigated using the shallow water equations (Chen & Guza 1998). Coupled
evolution equations describing the variations of edge wave amplitudes over a finite-size patch of undulating bathymetry were developed. Here similar evolution equations
are derived using the full linear equations, removing the shallow water restriction of
small (2N + 1)θ, where N is the maximum mode
number considered and θ is the
unperturbed planar beach slope angle. The present results confirm the shallow water
solutions for vanishingly small (2N + 1)θ and allow simple corrections to the shallow
water results for small but finite (2N + 1)θ. Additionally, multi-wave scattering cases
occurring only when (2N + 1)θ = O(1) are identified, and detailed descriptions are
given for the case involving modes 0, 1, and 2 that occurs only on a steep beach with
θ = π/12.
Direct simulation of unsteady axisymmetric
core–annular flow with high viscosity ratio
Authors: LI JIE , RENARDY YURIKO
Published: July 2002

Axisymmetric pipeline transportation of oil and water is simulated numerically as
an initial value problem. The simulations succeed in predicting the spatially periodic
Stokes-like waves called bamboo waves, which have been documented in experiments
of Bai, Chen & Joseph (1992) for up-flow. The numerical scheme is validated against
linearized stability theory for perfect core–annular flow, and weakly nonlinear saturation
to travelling waves. Far from onset conditions, the fully nonlinear saturation
to steady bamboo waves is achieved. As the speed is increased, the bamboo waves
shorten, and peaks become more pointed. A new time-dependent bamboo wave is
discovered, in which the interfacial waveform is steady, but the accompanying velocity
and pressure fields are time-dependent. The appearance of vortices and the locations
of the extremal values of pressure are investigated for both up- and down-flows.
Particle pressure and marginal stability limits for
a homogeneous monodisperse gas-fluidized bed:
kinetic theory and numerical simulations
Authors: KOCH DONALD L. , SANGANI ASHOK S.
Published: July 2002

A linear stability analysis is performed for the homogeneous state of a monodisperse
gas-fluidized bed of spherical particles undergoing hydrodynamic interactions and
solid-body collisions at small particle Reynolds number and finite Stokes number.
A prerequisite for the stability analysis is the determination of the particle velocity
variance which controls the particle-phase pressure. In the absence of an imposed
shear, this velocity variance arises solely due to the hydrodynamic interactions among
the particles. Since the uniform state of these suspensions is unstable over a wide range
of values of particle volume fraction φ and Stokes number St, full dynamic simulations
cannot be used in general to characterize the properties of the homogeneous state.
Instead, we use an asymptotic analysis for large Stokes numbers together with
numerical simulations of the hydrodynamic interactions among particles with specified
velocities to determine the hydrodynamic sources and sinks of particle-phase energy.
In this limit, the velocity distribution to leading order is Maxwellian and therefore
standard kinetic theories for granular/hard-sphere molecular systems can be used to
predict the particle-phase pressure and rheology of the bed once the velocity variance
of the particles is determined. The analysis is then extended to moderately large Stokes
numbers for which the anisotropy of the velocity distribution is considerable by using
a kinetic theory which combines the theoretical analysis of Koch (1990) for dilute
suspensions (φ [Lt ] 1) with numerical simulation results for non-dilute suspensions
at large Stokes numbers. A linear stability analysis of the resulting equations of
motion provides the first a priori predictions of the marginal stability limits for
the homogeneous state of a gas-fluidized bed. Dynamical simulations following the
detailed motions of the particles in small periodic unit cells confirm the theoretical
predictions for the particle velocity variance. Simulations using larger unit cells
exhibit an inhomogeneous structure consistent with the predicted instability of the
homogeneous gas–solid suspension.
The Convent of Santa Clara, the Elite and Social Change in Eighteenth Century Querétaro
Authors: GUNNARSDÓTTIR ELLEN
Published: July 2002

This article focuses on the changes that occurred within Querétaro's
elite from the late Habsburg to the high Bourbon period in colonial Mexico from
the perspective of its relationship to the convent of Santa Clara. It explores how
creole elite families of landed background with firm roots in the early seventeenth
century, tied together through marriage, entrepreneurship and membership in
Santa Clara were slowly pushed out of the city's economic and administrative
circles by a new Bourbon elite which broke with the social strategies of the past
by not sheltering its daughters in the city's most opulent convent.
Phatic communication and Relevance Theory: a
reply to Žegarac & Clark
Authors: WARD GREGORY , HORN LAURENCE R.
Published: July 2002

Recent work in Relevance Theory (henceforth RT) illustrates the coming of
age of modern pragmatic scholarship in creating an environment in which a
particular theory of pragmatics can be taken for granted, without explanation
or justification, and an analysis of a phenomenon previously unaccounted for
within that theory can be advanced. One is reminded of much of the recent
syntactic work within GB/Principles & Parameters/Minimalist Theory: the
dominance of the Chomskyan approach – particularly in certain geographic
regions – allows researchers, for better or worse, to simply assume the
correctness of the theory in their work and proceed to illustrate how that
theory might (or must) be extended or modified to accommodate a new class
of data. In this volume, Žegarac & Clark (1999) provide the latest illustration
of a similar strategy in pragmatics: the correctness of RT is assumed and an
analysis of ‘phatic communication’ proposed within that framework. On the
one hand, this constitutes an advance for pragmatic theory, since until
recently there was no comprehensive all-inclusive framework within which
certain pragmatic generalizations could be stated. If nothing else, RT has
served to raise a number of important issues surrounding the semantics-pragmatics interface, helping to crystallize the debate and make explicit
many assumptions that had been either implicit or non-existent in other
frameworks. In particular, RT work on scalar implicature/explicature and
on echoic mention and metalinguistic negation (e.g. Carston 1988, 1995;
Récanati 1989) has represented major advances in our understanding of
these phenomena and their theoretical implications. Thus, whatever one may
think of RT, it is a theory that must be taken seriously by anyone working
in this area. On the other hand, we find that RT suffers from one of the
principal afflictions of the aforementioned work in the GB/P&P/Minimalism
mainstream: a remarkable failure to address, come to terms with, and
incorporate the extensive previous literature on the topic under current
consideration.
Representing Minimalism
Authors: POOLE GEOFFREY
Published: July 2002

Juan Uriagereka,Rhyme and reason. Cambridge, MA: MIT Press, 1998. Pp.
xliii+669.

In this wide-ranging and ambitious volume, Juan Uriagereka sets as his goal
both a conceptual and a technical explication of Chomsky's Minimalist
Program as well as the siting of it within the broader context of scientific
inquiry into the nature of human beings and the natural world.
Reintroducing an old rhetorical device into modern scientific discourse, the
book is framed as a series of dialogues over six days between a Chomskyan
linguist and a sceptical interlocutor called ‘The Other’, a ‘hard’
scientist whose knowledge encompasses not only contemporary physics and biology,
but also mathematics and philosophy.

The temptation to frame a review using the same rhetorical device is
considerable. It is not much of an exaggeration to say that Uriagereka has
attempted to create a book about everything for anyone, and has attempted
to do so in a way that is unusual, clever and interesting. That he is largely
successful in this enterprise is truly remarkable. On the other hand, there is
also the lingering feeling that it is fractionally too clever, and fractionally too
ambitious, with the result that what could have easily been a classic of
modern scientific writing does not quite fulfill its potential.
Determinants of export-oriented industrial output in Ghana: the case of formal wood processing in an era of economic recovery
Authors: Owusu J. Henry
Published: July 2002

Like many other Sub-Saharan African countries, Ghana implemented an
orthodox Structural Adjustment Programme (SAP), to resuscitate its ailing
economy, in the early 1980s. Subsequently, there has been a dramatic expansion in
the production and export of processed wood. Based on an empirical study of Ghana's
formal wood processing industry, this paper discusses
the various determinants that have combined to boost the export-oriented
output in the industry, particularly in the first decade of the programme,
and assesses the extent to which the SAP-based policy actions account for
the change. The study concludes that adjustment played a major role in the
change, and suggests that even though SAP supporters and critics disagree
on the nature, dynamics and effects of the programme, government measures
under the programme are an indicator of what real commitment on the part
of African governments can do to engender production expansion in comparable African manufacturing industries.
Instability of higher-harmonic electrostatic dust cyclotron waves
Authors: SORASIO G. , ROSENBERG M.
Published: July 2002

Conditions for exciting higher-harmonic electrostatic dust cyclotron waves
in a collisional dusty plasma are investigated. Linear kinetic theory is used, and the
effects of neutral–charged particle collisions are taken into account. In a plasma
with negatively charged dust, electrostatic dust cyclotron waves can be driven unstable
by ions drifting along the magnetic field. It is found that, under certain
conditions, the critical ion drift for the excitation of higher-harmonic electrostatic
dust cyclotron waves (i.e., ω ∼ mΩd,
where m [ges ] 2 and Ωd is the dust cyclotron
frequency) can be comparable to the critical drift for the excitation of the fundamental
cyclotron harmonic (i.e., ω ∼ Ωd). Stability conditions are investigated for
ranges of parameters that may be relevant to laboratory dusty plasmas.
Covariant formulation of photon acceleration
Authors: MENDONÇA J. T. , HIZANIDIS K. , FRANTZESKAKIS D. J. , e SILVA L. OLIVEIRA , VOMVORIDIS J. L.
Published: July 2002

We present a covariant theory of photon acceleration in time-varying

plasmas. This is a ray-tracing model for frequency upshift of waves interacting
with

relativistic plasma perturbations, such as ionization fronts and plasma

wakefields. This theory explores the formal analogy between a photon in
a

plasma and a relativistic particle with a finite rest mass. The covariant

ray-tracing theory is applied to the case of photon acceleration by a modulated

wakefield. Threshold criteria for transition to chaos are derived.
Fully kinetic simulation of coupled plasma
and neutral particles in scrape-off layer
plasmas of fusion devices
Authors: BATISHCHEV O. V. , SHOUCRI M. M. , BATISHCHEVA A. A. , SHKAROFSKY I. P.
Published: July 2002

Fluid descriptions of plasmas, which are usually applied to a collisional plasma, can
only be justified for very small Coulomb Knudsen numbers. However, the scrape-off
layer (SOL) plasmas of experimental magnetic confinement fusion devices tend to
have operational regimes characterized by a Coulomb Knudsen number around 0.1.
In interesting detached regimes of an SOL plasma in a tokamak, when the plasma
detaches from the limiters or divertors, this number may increase along with the
local plasma gradients. Plasma gradients are also known to increase (and thus
drive non-local effects) in inertial confinement fusion. Neutrals, which are being
produced owing to plasma recombination at the plasma–divertor interface, may
be in a mixed collisional regime as well. Thus simultaneous kinetic treatments of
plasma and neutral particles with self-consistent evaluation of boundary conditions
at the material walls are required. We present a physical model and a numerical
scheme, and discuss results of purely kinetic simulations of plasmas and neutrals
for actual conditions in the Alcator C-Mod and Tokamak-de-Varennes experimental
tokamaks. Results for both steady-state and transient regimes of SOL plasma flow
are presented. Our approach, unlike particle-in-cell and Monte Carlo methods, is
free from statistical noise.
Parametric excitation of electromagnetic waves in a magnetized plasma
Authors: YUKHIMUK A. K. , YUKHIMUK V. A. , SIRENKO O. K. , VOITENKO Yu. M.
Published: July 2002

The parametric interaction of an upper-hybrid pump wave with kinetic
Alfvén and electromagnetic waves that propagate in parallel and perpendicular
directions to the ambient magnetic field is investigated on the basis of two-fluid
magnetohydrodynamics. A nonlinear dispersion relation describing three-wave interaction
and instability growth rates are found. The theoretical results are used
for the interpretation of satellite observations in the magnetospheric plasma. It
is shown that as a result of the decay of an upper-hybrid wave, electromagnetic
waves propagating in both parallel and perpendicular directions to the ambient
magnetic field are generated. The instability growth rate is much higher in the
case of left-polarized electromagnetic wave generation than in the case of ordinary
electromagnetic wave generation. The nonlinear parametric processes studied here
could also take place during powerful bursts on the Sun, and in the magnetosphere
of Jupiter.
Quasistatic evolution of a dissipative plasma
column in vacuum: errata and addenda
Authors: LO SURDO C.
Published: July 2002

We provide a revised, and substantially enriched, version of an old
study of ours, dealing with the theory of the slow evolution of a strictly
dissipative, cylindrical plasma column in vacuum [J. Plasma Phys.43, 217–237
(1990)]. After correcting a technical mistake made in our previous formulation
of the model of the physical system under consideration, we develop a fully
amended version of the associated theory, paying special attention to the
problem's well-posedness. A number of comments, generalizations and further
details have also been added.
Critical transitions in early life histories of short-finned squid, Illex illecebrosus as reconstructed from gladius growth
Authors: Perez José Angel A. , O'Dor Ronald K.
Published: July 2002

Early life growth of the short-finned squid, Illex illecebrosus (Mollusca: Cephalopoda), was reconstructed from periodic increments deposited on the gladius structure of squid collected in the Gulf Stream/Slope Water front and the Scotian Shelf. The general effects of environmental changes and lifestyle transitions in the variation of size-specific gladius growth was investigated. The offshore growth was exponential and at least six size-specific growth phases were distinguished. Paralarval growth ended at approximately 10 mm gladius length (GL). An important change in growth at 30–40 mm GL was associated with the shift from the macroplanktonic to micronektonic habitats and the transition from the Gulf Stream to Slope Water. The approximation to the Scotian Shelf/Slope Water Front was suggested as related to a growth transition at 68 mm GL. A change to linear growth occurred after the nektonic lifestyle was attained on shelf waters (90 mm GL).
Avoidance of dried biofilms on slate and algal surfaces by certain spirorbid and bryozoan larvae
Authors: Hamer John P. , Walker Graham
Published: July 2002

The effect of aerial drying of biofilmed surfaces to simulate a tidal emersion upon the settlement preferences of spirorbid and bryozoan larvae was investigated using choice experiments with still water conditions carried out in the laboratory. Aerial drying of biofilmed slates and pieces of Fucus serratus for 1 h at 20°C negated their usual settlement-inducing properties to larvae of Spirorbis spirorbis, S. tridentatus and Flustrellidra hispida. Such larval settlement preference may contribute to observed variations in the natural distribution of these species in the intertidal.
Behavioural effects of biofouling in a marine copepod
Authors: McAllen R. , Scott G.W.
Published: July 2002

The impact of biofouling by the filamentous bacteria Leucothrix mucor upon the body density and swimming behaviour of the harpacticoid copepod Tigriopus brevicornis was investigated. Biofouled individuals had a greater body density than non-fouled individuals. Biofouled and non-fouled animals swam similar distances and for similar periods of time during trials, but biofouled animals engaged in fewer, but longer bouts of swimming per trial and as a result experienced a lower swimming rate. These observations imply that biofouling has significant implications for the behavioural ecology of T. brevicornis.
Demystifying the ‘Ideal Progressive’: Resistance through Mimicked Modernity in Princely Baroda, 1900-1913
Authors: BHAGAVAN MANU
Published: July 2002

Current scholarship is replete with the praises of princely Baroda, the ‘ideal and progressive’ state which emerged and
prospered under the enlightened rule of Maharaja Sayaji Rao Gaekwad III in the early twentieth century. For example,
V. B. Kulkarni notes in his Princely India and Lapse of British Paramountcy that ‘It is . . . enough to end this
heart-warming story of wise princely governments by recalling the achievements of Sayajirao of Baroda . . . [in part]
because he gave an enlightened government to a chronically-misgoverned state . . .’.
China and the Issue of Postwar Indochina in the Second World War
Authors: Liu Xiaoyuan
Published: July 2002

China's foreign relations during the Second World War underwent a radical metamorphosis. The Chinese government under Chiang Kai-shek (Jiang Jieshi) earned new international respect by mounting a tenacious resistance against the Japanese enemy. By allying itself with powerful countries in the West for the first time in modern history, China emerged from its involuntary diplomatic isolation. The new Grand Alliance facilitated China's diplomatic initiatives seeking to eradicate the legal stigma of its semi-colonial status through the abrogation of the unequal treaties. In the process China also leaped to the rank of the ‘Big Four’. At a time when the Western colonialism was receding, the Japanese Empire was collapsing and national independence movements were on the rise in many Asian countries, China seemed positioned to achieve a new prominent leadership role in Asian and world affairs.
Une étude de Rm 2.12–16
Authors: MAERTENS P.
Published: July 2002

Après avoir souligné l’impartialité divine (Rm 2.11), Paul fait appel à ce qui semble être une maxime juive (v. 12) et qui traduit sûrement une position judaïsante: les païens subiront une destruction, contrairement aux Juifs qui passeront en jugement avant d’hériter le monde à venir. Mais en soulignant l’importance de la pratique (v. 13), l’apôtre réussit à réexaminer le cas de païens qui observent des préceptes de la loi (vv. 14–15). Comme pour les Juifs, le résultat de leur style de vie sera manifesté lors du jugement (v. 15). L’apôtre conclut en soulignant l’orthodoxie de sa position (v. 16).
DER ‘RAUB’ DER GOTTGLEICHHEIT: EIN RELIGIONSGESCHICHTLICHER VORSCHLAG ZU PHIL 2.6(–11)
Authors: VOLLENWEIDER SAMUEL
Published: July 2002

Phil 2.6b should not be understood in the manner of an idiom but in a clearly negative way
(‘booty’). The central key to Phil 2.6b is offered by biblical, Jewish and Hellenistic
traditions about a usurpation of equality with God by kings and rulers (cf. Isa 14.12–15;
hubris of god-like kings like Alexander, who ‘robbed’ their position). The
self-humiliating Christ (who did not claim equality with God) is conceived as an antitype to the
self-elevating rulers of the world; his Lordship is not based on usurpation. Phil 2.6–11 is
keenly aware of the Jewish notion of the One and Only God (cf. John 5.18); the mantle of
God's Oneness also embraces Christ as the Lord.
Dietary protein and zinc restrictions independently modify
a Heligmosomoides polygyrus (Nematoda) infection in mice
Authors: BOULAY M. , SCOTT M. E. , CONLY S. L. , STEVENSON M. M. , KOSKI K. G.
Published: July 2002

The effects of dietary protein and zinc restrictions on
Heligmosomoides polygyrus were compared following primary and

challenge infection in female BALB/c mice fed either control (24%),

marginal (7%) or low (3%) protein combined with
either high or low zinc (60 or 3 mg Zn/kg diet). Dietary protein
restriction (3%) resulted in significantly lower body
weight gain. As well, blood urea nitrogen (BUN) significantly decreased

with decreasing dietary protein level. However,
neither plasma albumin concentration nor relative thymus or spleen
weights were reduced. Marginal zinc deficiency was
confirmed by significantly lower tibia and liver zinc concentration, but

food intake, body weight gain, relative thymus and
spleen weights, and alkaline phosphatase activity were not altered. On

day 29 post-primary infection, worm burdens were
significantly higher in mice fed either marginal or low protein and in

mice fed a low zinc diet, while parasite egg output
was significantly higher in mice fed both low protein and low zinc diets.

Immune status was compromised in mice fed low
protein (significantly lower serum IgG1 and lower eosinophilia), and in

mice fed low zinc diet (significantly lower
eosinophilia). Early in the infection, IgE titres were elevated in mice

fed low protein or low zinc, but IgE titres declined
to levels lower than the control diet groups after 14–21 days.
On day 29 post-challenge infection, worm burdens and
parasite egg output were significantly higher in mice fed low protein,

whereas the other groups had expelled almost all
parasites. Dietary restriction had no effect on serum IgE. Significantly

reduced serum IgG1 titres and eosinophilia in mice
fed 3% protein supported the view that low dietary protein but not
low zinc increased host susceptibility to H. polygyrus
by compromising host immune function following reinfection in immunized
mice.
A Note on J. L. Austin and the Drama
Authors: Magee Bryan
Published: July 2002

A play's text is nearly all talk, and in the performance of a play the physical activity is sparse and exceedingly limited. Used of a play, the term ‘action’ does not mean what it normally means. Its true meaning is illuminated by reference to J. L. Austin and his doctrine of speech-acts. Dramatic action is, for the most part, speech-action. And a skilful manipulation of speech-acts enables the gifted dramatist not only to tell a story but to communicate what is going on below the surface.
Full-spectrum fluorescent lighting: a review of its effects on physiology and health
Authors: L. McCOLL SHELLEY , A. VEITCH JENNIFER
Published: July 2002

Background. Full-spectrum fluorescent lighting (FSFL) has been credited with causing dramatic beneficial effects on a wide variety of behaviours, mental health outcomes and physical health effects, as compared to other fluorescent lamp types. These effects are hypothesized to occur because of similarity between FSFL emissions and daylight, which is said to have evolutionary superiority over other light sources.

Method. This review, covering the period 1941–1999, critically considers the evidence for direct effects of FSFL through skin absorption as well as indirect effects on hormonal and neural processes.

Conclusions. Overall, the evidence does not show dramatic effects of fluorescent lamp type on behaviour or health, neither does it support the evolutionary hypothesis.
Life events and psychosocial factors in elderly suicides – a case–control study
Authors: RUBENOWITZ E. , WAERN M. , WILHELMSON K. , ALLEBECK P.
Published: July 2002

Background. Stressful life events, such as family conflicts, separation, bereavement, somatic illness and financial problems are common antecedents of suicide. Studies on suicide among younger persons dominate the literature, despite the fact that a large proportion of suicides occur among elderly persons.

Methods. The occurrence of stressful life events was investigated among elderly suicide cases and population controls. The study was conducted in the southwestern part of Sweden and included 85 persons (46 males and 39 females) 65 years and above who had committed suicide from January 1994 to May 1996. Population controls (84 males and 69 females) were randomly selected. Interviews were carried out with the controls and with informants for the suicide cases. Questions on sociodemographic background, mental and somatic health status, and life events (0–6, 7–12 and 13–24 months preceding suicide/interview) were included in the interviews.

Results. Somatic illness, family discord and financial trouble were significant risk factors during all three time periods. Other risk factors were mental disorder, lower education, feelings of loneliness and previous suicide in the family. Factors associated with a decreased risk included active participation in organizations and having a hobby. Variables that remained in the multivariate logistic regression model were mental disorder (men, odds ratio (OR) = 62·4, 95% CI 17·9–217·5; women, OR = 55·9, 95% CI 14·1–222·3) and family discord (men, OR = 10·0, 95% CI 1·7–59·8; women, OR = 9·2, 95% CI 1·9–44·8).

Conclusions. Mental disorder and family discord were the two major risk factors for suicide among elderly men and women.
Measuring core bereavement phenomena
Authors: BURNETT P. , MIDDLETON W. , RAPHAEL B. , MARTINEK N.
Published: July 2002

As part of a longitudinal study of bereavement phenomena in three groups, bereaved
spouses, bereaved adult children and bereaved parents, scale development was carried out using a
pool of bereavement phenomenology questions administered prospectively. The items were derived
from the literature, in particular studies dealing with the measurement of grief/bereavement, as well
as from clinical experience. Factor analysis of theoretically grouped items produced seven subscales,
three of which tapped frequently experienced phenomena in the bereaved. These three subscales
formed the basis of a single measure, labelled the Core Bereavement Items (CBI), which
demonstrated high reliability and sound face and discriminant validity. Preliminary analysis
suggested that the CBI will prove to be a reliable and valid instrument with respect to the measure
of core bereavement phenomena in commonly bereaved groups in Western society.
Assessment of a new self-rating scale for post-traumatic
stress disorder
Authors: DAVIDSON J. R. T. , BOOK S. W. , COLKET J. T. , TUPLER L. A. , ROTH S. , DAVID D. , HERTZBERG M. , MELLMAN T. , BECKHAM J. C. , SMITH R. D. , DAVISON R. M. , KATZ R. , FELDMAN M. E.
Published: July 2002

Background. In post-traumatic stress disorder (PTSD) there is a need for self-rating scales that
are sensitive to treatment effects and have been tested in a broad range of trauma survivors.
Separate measures of frequency and severity may also provide an advantage.

Methods. Three hundred and fifty-three men and women completed the Davidson Trauma Scale
(DTS), a 17-item scale measuring each DSM-IV symptom of PTSD on 5-point frequency and
severity scales. These subjects comprised war veterans, survivors of rape or hurricane and a
mixed trauma group participating in a clinical trial. Other scales were included as validity
checks as follows: Global ratings, SCL-90-R, Eysenck Scale, Impact of Event Scale and
Structured Clinical Interview for DSM-III-R.

Results. The scale demonstrated good test–retest reliability (r = 0·86), internal consistency
(r = 0·99). One main factor emerged for severity and a smaller one for intrusion. In PTSD diagnosed
subjects, and the factor structure more closely resembled the traditional grouping of symptoms.
Concurrent validity was obtained against the SCID, with a diagnostic accuracy of 83% at a DTS
score of 40. Good convergent and divergent validity was obtained. The DTS showed predictive
validity against response to treatment, as well as being sensitive to treatment effects.

Conclusions. The DTS showed good reliability and validity, and offers promised as a scale which
is particularly suited to assessing symptom severity, treatment outcome and in screening for the
likely diagnosis of PTSD.
Recollections of parental behaviour, adult
attachment and mental health: mediating and
moderating effects
Authors: GITTLEMAN M. G. , KLEIN M. H. , SMIDER N. A. , ESSEX M. J.
Published: July 2002

Background. Attachment theory posits links between early
experiences with parents, adult
relationships and adult mental health, but does not specify whether these
are independent,
mediating, or moderating effects.

Methods. Associations of parent's behaviour on the Parental
Bonding Instrument, adult attachment
styles and three dimensions of mental health were investigated in a large
sample of women and men.

Results. Men and women with secure styles recalled higher levels
of care from both parents than
those with fearful styles. Maternal and paternal control were more consistent
predictors of increased
distress for men than for women. Fearful and preoccupied adult styles were
associated with higher
levels of distress in both men and women. While adult styles had few mediating
effects on the
association of parental behaviour and mental health, interactions between
the fearful style and
parental variables suggested that this form of insecurity sometimes accentuated
the impact of high
parental care or low paternal control on mental health in both men and
women; among women,
however, the secure style seemed to buffer somewhat the negative effect
of high parental control.

Conclusion. Although the amount of variance explained by either
parental behaviour or adult styles
was modest, patterns of moderating effects of adult styles on associations
between parental
behaviour and mental health suggested that both continuity and discontinuity
principles can be
applied to understanding these links.
The impact of widowhood on depression:
findings from a prospective survey
Authors: CARNELLEY K. B. , WORTMAN C. B. , KESSLER R. C.
Published: July 2002

Background. We investigated the impact of widowhood on depression and how resources and
contextual factors that define the meaning of loss modified this effect.

Method. In a prospective, nationally representative sample of women in the US aged 54 or older we
compared 64 women who were widowed in the 3 years between data collection waves with 431
women who were stably married over the time interval.

Results. Those who became widowed reported more depression than controls for 2 years following
the loss. However, this effect was confined to respondents whose husbands were not ill at baseline.
Widowed women whose husbands were ill at baseline already had elevated depression in the
baseline interview and did not become significantly more depressed after the death. Consistent with
this result, women who were not depressed pre-bereavement were most vulnerable to depression
following the loss of an ill spouse during the first year of widowhood.

Conclusions. Results suggest that spouses' illness may forewarn wives of their impending loss and
these women may begin to grieve before his death. Those forewarned women who are not depressed
pre-bereavement may experience the most post-bereavement depression. Findings are discussed in
light of previous, more methodologically limited studies.
The activity of the quadriplegic God
Authors: PAILIN DAVID A.
Published: July 2002

Since theistic faith involves the notion of God as personally agential
and since it faces difficulties in establishing its credibility in view both of problems
in warrantably ascribing natural, historical and personal states to divine activity
and of the counterevidence of evil, this paper takes up the story of a quadriplegic
patient and certain remarks by Whitehead and Hartshorne to explore the viability
of a concept of divine activity that is non-coercive but significant. In order to develop
this concept of God's agency and to warrant its credibility, the essential kenoticism
of the divine is also discussed.
Measuring facial expressions by computer image analysis
Authors: Bartlett Marian Stewart , Hager Joseph C. , Ekman Paul , Sejnowski Terrence J.
Published: July 2002

Facial expressions provide an important behavioral measure for the study of emotion, cognitive processes, and social interaction. The Facial Action Coding System (Ekman & Friesen, 1978) is an objective method for quantifying facial movement in terms of component actions. We applied computer image analysis to the problem of automatically detecting facial actions in sequences of images. Three approaches were compared: holistic spatial analysis, explicit measurement of features such as wrinkles, and estimation of motion flow fields. The three methods were combined in a hybrid system that classified six upper facial actions with 91% accuracy. The hybrid system outperformed human nonexperts on this task and performed as well as highly trained experts. An automated system would make facial expression measurement more widely accessible as a research tool in behavioral science and investigations of the neural substrates of emotion.
From neural constructivism to cognitive constructivism: The steps to be taken
Authors: Demetriou Andreas
Published: July 2002

Quartz & Sejnowski's (Q&S's) model for constructive learning agrees with the basic assumptions of mainstream cognitive developmental theories. However, it does not detail the neural equivalents of (1) the process of cognitive change per se, (2) the construction and functioning of thought modules, and (3) the involvement of “mindreading” and “mindsteering” in constructive learning. Specifying these equivalents is necessary if cognitive developmental neuroscience and mainstream cognitive development are to be directly connected.
Studies of synaptic elimination identify an intersection of neurocomputational and neurodevelopmental perspectives
Authors: Hoffman Ralph E.
Published: July 2002

In order to reach a better understanding of brain function, conceptual synergies linking empirical neurobiological studies and neurocomputational studies should be pursued. I describe an example of a potential synergy based on studies of neural network pruning. Simulations demonstrate that selective elimination of connections enhances the computational capacity of networks capable of temporal processing. These findings may shed light on the functional significance of postnatal neuro-developmental pruning of cortical connections that occurs in mammals.
Continued vitality of the Freudian theory of dreaming
Authors: Shevrin Howard , Eiser Alan S.
Published: July 2002

A minority position is presented in which evidence will be cited from the Hobson, Solms, Revonsuo, and Nielsen target articles and from other sources, supporting major tenets of Freud's theory of dreaming. Support is described for Freud's view of dreams as meaningful, linked to basic motivations, differing qualitatively in mentation, and wish-fulfilling.

[Hobson et al.; Nielsen; Revonsuo; Solms]
Bridging the gap: Dynamics as a unified view of cognition
Authors: Harter Derek , Graesser Arthur C. , Franklin Stan
Published: July 2002

Top-down dynamical models of cognitive processes, such as the one presented by Thelen et al., are important pieces in understanding the development of cognitive abilities in humans and biological organisms. Unlike standard symbolic computational approaches to cognition, such dynamical models offer the hope that they can be connected with more bottom-up, neurologically inspired dynamical models to provide a complete view of cognition at all levels. We raise some questions about the details of their simulation and about potential limitations of top-down dynamical models.
Problematic aspects of embodied memory
Authors: Benjamin Aaron S. , Bjork Robert A.
Published: July 2002

Glenberg's theory is rich and provocative, in our view,
but we find fault with the premise that all memory representations
are embodied. We cite instances in which that premise mispredicts
empirical results or underestimates human capabilities, and we suggest
that the motivation for the embodiment idea – to avoid the
symbol-grounding problem – should not, ultimately, constrain
psychological theorizing.
Action patterns, conceptualization, and artificial intelligence
Authors: Franklin Stan
Published: July 2002

This commentary connects some of Glenberg's ideas
to similar ideas from artificial intelligence. Second, it briefly
discusses hidden assumptions relating to meaning, representations,
and projectable properties. Finally, questions about mechanisms,
mental imagery, and conceptualization in animals are posed.
Is memory caught in the mesh?
Authors: MacLeod Colin M.
Published: July 2002

Can memory be cast as a system that meshes events to actions?
This commentary considers the concepts of mesh versus association,
arguing that thus far the distinction is inadequate. However, the goal
of shifting to an action-based view of memory has merit, most notably
in emphasizing memory as a skill and in focusing on processes as
opposed to structures.
Embodiment, enaction, and developing spatial knowledge: Beyond deficit egocentrism?
Authors: Rutkowska Julie C.
Published: July 2002

Traditional cognitivism treats a situated agent's point
of view in terms of deficit egocentrism. Can Ballard et al.'s
framework remedy this characterization? And will its fusion of
computational and enactivist explanations change assumptions about
what cognition is? “Yes” is suggested by considering human
infants' developing spatial knowledge, but further questions are
raised by analysis of their robot counterparts.
Learning and synaptic plasticity
Authors: Robinson G. B.
Published: July 2002

Controversy surrounds several experiments that have addressed
whether selective synaptic strengthening occurs during learning. To
date, the evidence suggests that widespread alterations in synaptic
strength, through either kindling or electroconvulsive shock, can
disrupt this hypothetical process. The lack of evidence for selective
modification of learning through LTP stimulation, however, provides
difficulties for both the prevailing hypothesis and the hypothesis
advanced by Shors & Matzel. Subsequent experiments may
indicate a role for LTP in both learning and arousal.
What exactly is central to the role of central neuroplasticity in persistent pain?
Authors: Coderre Terence J. , Katz Joel
Published: July 2002

The commentaries on our target article have raised important
issues about central neuroplasticity and its role in persistent pain
states. Some suggest that central neuroplasticity plays nothing
more than a minor role in persistent pain, while others argue that
persistent pain depends critically on peripheral inputs for its
maintenance. Some stress that persistent pain relies to a large
extent on changes in the brain and on centrifugal inputs from brain
to spinal cord, whereas others argue that it depends on alterations
in inhibitory as well as excitatory systems. We attempt to address
each of the commentators' points, while defending our position
that central neuroplasticity is critical to pathological persistent
pain states.
Processing capacity defined by relational complexity: Implications for comparative, developmental, and cognitive psychology
Authors: Halford Graeme S. , Wilson William H. , Phillips Steven
Published: July 2002

Working memory limits are best defined in terms of the
complexity of the relations that can be processed in parallel.
Complexity is defined as the number of related dimensions or sources
of variation. A unary relation has one argument and one source of
variation; its argument can be instantiated in only one way at a time.
A binary relation has two arguments, two sources of variation, and
two instantiations, and so on. Dimensionality is related to the number
of chunks, because both attributes on dimensions and chunks are
independent units of information of arbitrary size. Studies of working
memory limits suggest that there is a soft limit corresponding to the
parallel processing of one quaternary relation. More complex concepts
are processed by “segmentation” or “conceptual
chunking.” In segmentation, tasks are broken into components
that do not exceed processing capacity and can be processed serially.
In conceptual chunking, representations are “collapsed”
to reduce their dimensionality and hence their processing load, but at
the cost of making some relational information inaccessible. Neural
net models of relational representations show that relations with
more arguments have a higher computational cost that coincides with
experimental findings on higher processing loads in humans. Relational
complexity is related to processing load in reasoning and sentence
comprehension and can distinguish between the capacities of higher
species. The complexity of relations processed by children increases
with age. Implications for neural net models and theories of cognition
and cognitive development are discussed.
Null hypothesis tests and theory corroboration: Defending NHSTP out of context
Authors: Dar Reuven
Published: July 2002

Chow's defense of NHSTP ignores the fact that in
psychology it is used to test substantive hypotheses in
theory-corroborating research. In this role, NHSTP is not only
inadequate, but damaging to the progress of psychology as
a science. NHSTP does not fulfill the Popperian requirement that
theories be tested severely. It also encourages nonspecific
predictions and feeble theoretical formulations.
“With friends like this . . .”: Three flaws in Chow's defense of significance testing
Authors: Harris Richard J.
Published: July 2002

Chow's book should be read only by those who already have
a firm enough grasp of the logic of significance testing to separate
the few valid, insightful points from the many incorrect statements
and misrepresentations.
Might we adopt the learning-related account instead of the talent account?
Authors: Hatano Giyoo
Published: July 2002

Although Howe et al.'s survey shows little evidence
for the talent account, it is premature to conclude that individual
differences in achievement can be attributed largely to training and
early experience. Moreover, such an empiricist account has problematic
social implications, especially in cultures in which effort is
emphasized. The aptitude account is thus proposed as a third
alternative.