bluuebunny/crossref_metadata_2025 huggingface dataset:
Classification of robust isolated vortices in

two-dimensional hydrodynamics
Authors: CHAVANIS P. H. , SOMMERIA J.
Published: July 2002

We determine solutions of the Euler equation

representing isolated vortices (monopoles,

dipoles) in an infinite domain, for arbitrary values of

energy, circulation, angular momentum and impulse. A linear

relationship between vorticity and stream function is

assumed inside the vortex (while the flow is irrotational

outside). The emergence of

these solutions in a turbulent flow is justified by the

statistical mechanics of continuous

vorticity fields. The additional restriction of mixing to a

‘maximum-entropy bubble’,

due to kinetic constraints, is assumed. The linear

relationship between vorticity and

stream function is obtained from the statistical theory in

the limit of strong mixing

(when constraints are weak). In this limit, maximizing

entropy becomes equivalent to

a kind of enstrophy minimization. New stability criteria

are investigated and imply

in particular that, in most cases, the vorticity must be

continuous (or slightly discontinuous) at the vortex boundary.

Then, the vortex radius is automatically determined

by the integral constraints and we can obtain a classification

of isolated vortices

such as monopoles and dipoles (rotating or translating) in

terms of a single control

parameter. This article generalizes the classification

obtained in a bounded domain

by Chavanis & Sommeria (1996).
The motion of fibres in turbulent flow
Authors: OLSON JAMES A. , KEREKES RICHARD J.
Published: July 2002

Equations of mean and fluctuating velocities in rotation and translation
have been
derived for rigid thin inertialess fibres moving in a turbulent fluid.
The derived
equations for mean motion are general to fluid velocities that vary nonlinearly
along
the length of the fibre. From the equations of fluctuating fibre velocity,
rotational and
translational dispersion coefficients were derived. The resulting dispersion
coefficients
were shown to decrease as the ratio of fibre length to Lagrangian integral
length scale
of the turbulence increased.
Transport of reactive tracers in rock fractures
Authors: CVETKOVIC V. , SELROOS J. O. , CHENG H.
Published: July 2002

Transport of tracers subject to mass transfer reactions in single
rock fractures is
investigated. A Lagrangian probabilistic model is developed where the mass
transfer
reactions are diffusion into the rock matrix and subsequent sorption in
the matrix, and
sorption on the fracture surface as well as on gauge (infill) material
in the fracture.
Sorption reactions are assumed to be linear, and in the general case kinetically

controlled. The two main simplifying assumptions are that diffusion in
the rock matrix
is one-dimensional, perpendicular to the fracture plane, and the tracer
is displaced
within the fracture plane by advection only. The key feature of the proposed
model is
that advective transport and diffusive mass transfer are related in a dynamic
manner
through the flow equation. We have identified two Lagrangian random variables
τ
and β as key parameters which control advection and diffusive mass
transfer, and
are determined by the flow field. The probabilistic solution of the transport
problem
is based on the statistics of (τ, β), which we evaluated analytically
using first-order
expansions, and numerically using Monte Carlo simulations. To study (τ,
β)-statistics,
we assumed the ‘cubic law’ to be applicable locally, whereby
the pressure field is
described with the Reynolds lubrication equation. We found a strong correlation

between τ and β which suggests a deterministic relationship
β∼τ3/2; the exponent
3/2 is an artifact of the ‘cubic law’. It is shown that
flow dynamics in fractures has
a strong influence on the variability of τ and β, but a comparatively
small impact
on the relationship between τ and β. The probability distribution
for the (decaying)
tracer mass recovery is dispersed in the parameter space due to fracture
aperture
variability.
Dynamics of corotating vortex pairs in
the wakes of flapped airfoils
Authors: CHEN A. L. , JACOB J. D. , SAVAŞ Ö.
Published: July 2002

The behaviour of a pair of corotating vortices in the wake of a
flapped airfoil is
experimentally studied in a water towing tank. Reynolds numbers based on
total
circulation of the vortices range from 1.0×104 to
6.4×104. Planar velocity vector
fields and their gradients are derived from PIV images using an adaptive
Lagrangian
parcel tracking algorithm. Isovorticity surfaces are extracted from time
series of
planar vorticity data. The behaviour of the vortices is tracked by using
various
moments of both the probability density distribution and the spatial distribution
of
their streamwise vorticity. All vortices show a Lamb–Oseen circulation
distribution
when they are clearly identifiable. Further, vortices from the apless wing
exhibit
Lamb–Oseen velocity and vorticity distributions with slow growth.
All corotating
vortex pairs are observed to merge at about 0.8 orbit periods. First-order
statistics of
the flow field remain invariant during the merger. The higher-order moments
of the
vorticity distribution show strong time dependence, which implies three-dimensionality

of the flow resulting from vortex stretching. The strengths of the individual
vortices
before merger are constant, and the total circulation before and after
merger remains
constant within the range of observations. The trajectory of the centre
of vorticity
remains unaffected by the merger process. The merger is preceded by a splitting
of
the weaker vortex into filaments which, depending on the relative strengths
of the
vortices, can occur in the radial direction, the axial direction, or a
combination of the
two. Mechanisms contributing to the merger dynamics are discussed.
A phenomenological model for the contact region of an evaporating meniscus on a
superheated slab
Authors: MORRIS S. J. S.
Published: July 2002

The evaporating meniscus of a perfectly wetting fluid exhibits an apparent contact
angle Θ that is a function of superheat. Existing theory predicts Θ and the heat flow
from the contact region as part of the solution of a free-boundary problem. That
theory admits the possibility that much of the heat flow occurs
at the nanometre scale [lscr ]Θ
at which Θ is determined. Here, the heat flow at that scale is proved negligible in
typical applications. A phenomenological model of the contact region then holds since the
part of the wetting film thinner than [lscr ]Θ can be replaced by an apparent contact line.
Self-consistency arguments are used to derive conditions under which (i) the phase
interface can be taken as linear with assumed contact angle Θ; (ii) the heat flux to the
liquid side of the phase interface is given by Newton's law of cooling with predicted
heat transfer coefficient h; and (iii) the temperature satisfies Laplace's equation within
the phases. When these conditions are met, prediction of the heat flow is decoupled
from the physically non-trivial problem of predicting Θ. Next, this conduction theory
is used to find the heat flow from the contact region of a meniscus on a conductive
slab. The solution depends on Θ, the liquid–solid conductivity ratio
k = K[lscr ]/Ks and a
Biot number [Bscr ] = hd/K[lscr ] based on slab thickness
d. Asymptotic and numerical analysis
is used to find the temperature in the double limit
[Bscr ]−1 → 0 and k → 0. The solution
has an inner-and-outer structure, and properties of the inner region prove universal.
Formulae given here for the heat flow and contact line temperature on a slab thus
apply to more complex geometries. Further, the solution explains the main features
seen in published simulations of evaporation from conductive solids. Near the contact
line, the solid temperature varies rapidly on the scale d of the slab thickness, but
varies slowly with respect to the liquid temperature. The solid temperature thus proves
uniform at the scale on which Θ is determined. Lastly, the quantitative predictions of
the simplified model are verified against both new and published numerical solutions
of the existing theory. In typical applications, the new formulae give the heat flow and
contact line temperature with an error of about 10%. This error is due to the
approximations made to derive the simplified model, rather than to those made to solve it.
Trapped in decline? Reassessing agrarian change and economic diversification on the Uluguru Mountains, Tanzania
Authors: Ponte Stefano
Published: July 2002

Analysing the dynamics of agrarian change and economic diversification is
central for understanding the current transformation of African countries
under market reforms. This article examines the complex changes taking
place in the densely populated Uluguru Mountains of Tanzania, and places
the Uluguru case in the context of wider debates dealing with market liberalisation,
economic diversification, poverty, and inequality. It argues that
rural households are not ‘trapped in decline’ on the Uluguru Mountains, as
depicted in previous literature. Under the harsh realities of farming in this
area, households can improve their livelihoods in three ways – short of migrating
and in addition to relying on remittances. These are to expand land
cultivated in the surrounding plains, to experiment with alternative farming
systems, and to increase non-farm income. Uluguru households are doing all
of the above, with a certain degree of success. Economic diversification can
thus play an important role in improving rural livelihoods in Tanzania and
beyond, but this process is more likely to take place in locations with well-established
economic ties and relatively good access to major markets.
A note on the compression ratio in MHD
shocks
Authors: KABIN K.
Published: July 2002

Abstract. We present an analysis of the compression ratio in MHD shocks. Although
the equation describing the compression ratio has been in the literature
for decades, we believe that our results are interesting and complementary to the
earlier research. We concentrate on the behavior of the compression ratio in a bow
shock as a function of the angle between the shock normal and the plasma velocity.
For this problem, we find non-unique solutions in certain regimes, which we
investigate in detail. We also find regimes where the compression ratio in fast bow
shocks achieves a local maximum in more than one location. In the last section,
we consider the compression ratio in slow shocks and make some conclusions about
the shape of the shock in this flow regime.
Radiative collapse in an impurity-seeded
spinning gas-puff staged pinch
Authors: MIRZA ARSHAD M. , AHMAD ZAHOOR , KHATTAK N. A. D. , MURTAZA G.
Published: July 2002

The dynamics and thermonuclear fusion parameters of a spinning
gas-puff staged
pinch are investigated by considering a DT-fibre plasma seeded with a Kr
impurity.
The effects of anomalous heating, line radiations from Kr, α-heating
and radiative
collapse are studied for different spin velocities Ω0,

keeping the spin coupling
parameter f0 (=0.1) fixed. Numerical
results indicate that the choice of Ω0 is highly
critical. Large values of the spin velocities although provide stabilization
against
the R–T instability in the final stage of compression, but causes
an adverse reduction
in the values of the plasma parameters that are essential to achieve controlled

fusion. Our analysis suggests that a judicious choice of spin velocity
can provide
the desired temperature and density when we seed a DT-fibre plasma with
a small
fraction of Kr impurity to initiate radiative collapse.
Burmese
Authors: Watkins Justin W.
Published: July 2002

Burmese is the official language of Burma. (In English, ‘Burmese’ and ‘Burma’ are also known as ‘Myanmar’, and ‘Rangoon’ as ‘Yangon’.) It is the major language of the Burmic branch of Tibeto-Burman, and is spoken natively by upwards of 30 million people in the lower valleys of the Irrawaddy and Chindwin rivers, the central plain of Burma and the Irrawaddy Delta, and non-natively by up to another 10 million speakers of other languages in Burma.
Foraging behaviour of Carcinus maenas on Mytilus edulis: the importance of prey presentation
Authors: Burch Alexandra , Seed Raymond
Published: July 2002

The manner in which mussels, Mytilus edulis, are presented to Carcinus maenas significantly influences crab prey-selection, resulting in different foraging behaviour. Handling techniques, breaking and handling times, percentage flesh eaten and prey value curves were compared when mussels of the following size-classes, 5–10, 10–15, 15–20, 20–25, 25–30 mm shell length, were presented singly and when they were presented as part of a group to crabs of 30–55 mm carapace width. When prey were presented singly, crabs used four size-specific opening techniques; outright crushing and directed crushing were used on smaller prey whilst boring and edge-chipping were used on larger, more resistant mussels. However, when mussels were presented as part of a group, boring and edge-chipping were never observed since larger mussels were not consumed. Handling time increased exponentially with mussel size irrespective of how mussels were presented, but, when crabs fed on mussels presented as part of a group, handling times tended to be shorter than when they fed on similar-sized mussels presented singly. The median percentage of flesh left uneaten in discarded shells ranged between 9.58 and 25.25% and was significantly greater than the median percentage of flesh left in the shells of mussels presented singly, which ranged between 4.66 and 14.70%. All resultant prey value curves were convex in shape, but the predicted optimal prey size altered with modifications in prey presentation. Similarly, when crabs of 30–65 mm carapace width were presented with groups of mussels comprised of different proportions of different sizes of mussels, size-class vulnerability was not fixed but altered significantly with the relative proportions in which these were presented. Thus, when the relative number of mussels in the smaller size groups were increased so was their vulnerability, indicating that prey size preference is flexible and not fixed.
First record of Amphiura securigera (Echinodermata: Ophiuroidea) in the Tyrrhenian (Mediterranean) Sea
Authors: Rinelli P.
Published: July 2002

The first finding of the brittle star Amphiura securigera (Echinodermata: Ophiuroidea) in the Tyrrhenian Sea is reported. According to literature data, biotopic and edaphic features of the bottom indicate that this species preferentially lives in detritic mud-free biotopes characterized by good water circulation. Present data show that in the Mediterranean Sea A. securigera extends its bathymetric range as far as the circalittoral and upper bathyal floors.
Corruption and Redemption: The Legend of Valluvar and Tamil Literary History
Authors: Blackburn Stuart
Published: July 2002

This [the Valluvar legend] is one of the traditions which are so repugnant to inveterate popular prejudice that they appear too strange for fiction, and are probably founded on fact. (Robert Caldwell 1875:132).

If we now recognize that literary history is more than a history of literature, it is perhaps less widely accepted that the writing of literary history is an important subject for literary historiography. Yet literary histories are a rich source for understanding local conceptions of both history and literature. More accessible than archaeology, more tangible than ethnology, literary histories are culturally constructed narratives in which the past is reimagined in the light of contemporary concerns. Certainly in nineteenth-century India, the focus of this essay, literary history was seized upon as evidence to be advanced in the major debates of the time; cultural identities, language ideologies, civilization hierarchies and nationalism were all asserted and challenged through literary histories in colonial India. Asserted and challenged by Europeans, as well as Indians.
From Transience to Immanence: Consumption, Life-Cycle and Social Mobility in Kerala, South India
Authors: Osella Filippo , Osella Caroline
Published: July 2002

In this paper, we explore some ways through which the adoption of specific consumption practices enables members of a South-Indian ex-untouchable community, Izhavas within Kerala, to objectify and redefine their self-perceived and other-perceived social position, and to concretize and make sense of their attempts to achieve generalized upward mobility. Located within individual, familial and group mobility strategies and developmental cycles, consumption assumes a long-term dimension, oriented towards present and future. Consumption practices also take on a normative aspect: youthful orientations towards transience and ephemerality should be replaced by a mature demeanour directed towards duration and permanency, and achievement of householder status. ‘Householders’ negotiate their paths through a complex consumer culture where values of transience and durability articulate with a local/foreign continuum. The labouring poor, whose consumption is severely limited, remain unable, in the eyes of the majority, to attain mature householder status. While Dalit castes withdraw into virtuosity in arenas such as fashion, labouring Izhavas struggle unsuccessfully to maintain distinction and join the mainstream.
The Dramatic Function of the Running Slave Rhoda (Acts 12.13–16): A Piece of Greco-Roman Comedy
Authors: HARRILL J. ALBERT
Published: July 2002

Rhoda, the slave maid (παιδισκη) in Acts 12.13–16, has been seen as a classic example of a touch of realism that lends authenticity to Luke's narrative: the vivid and precise detail of her flighty joy presents such a candid snapshot of her individuality and eccentric Christian faith that it could only come from a historical source, perhaps the eyewitness reminiscence of Rhoda herself. While less willing than earlier commentators to accept the description in its final form as factual, more recent scholars still perpetuate the goal of discerning the historical core behind the account and continue to read it as a piece of realistic drama. Many, to be sure, have detected in the scene the presence of other elements, such as comedy and extraordinary suspense, but this idea is downplayed or subordinated as further evidence of realism; a few discount the idea as a modern reading. Nonetheless, a consensus emerges: Rhoda's dramatic function in the narrative is to heighten realism. Some scholars then discover a further theological theme of liberation: Rhoda's genuine, assertive behaviour to speak her mind ‘breaks down’ the oppressive hierarchy between master and slave – revealing Luke's so-called subversion of slavery as a social institution – and the subsequent vindication of Rhoda's speech as trustworthy authenticates and uplifts the Christian witness of women (cf. Gal 3.28).
The Jerusalem Decrees (Acts 15.20, 29 and 21.25) and the Incident at Antioch (Gal 2.11–14)
Authors: TAYLOR JUSTIN
Published: July 2002

The ‘Jerusalem decrees’ of Acts 15.20, 29 and 21.25 can be interpreted both as ‘Noachide commandments’, implicitly keeping the separation between Jews and Gentiles, and as analogous to the decrees for resident aliens in Lev 17–18 and elsewhere, implicitly allowing Gentiles to associate with Jews under certain conditions. What is at stake is the status to be assigned to Gentiles by the community of Jewish believers in Jesus. These interpretations correspond to the attitudes towards Gentile believers at Antioch manifested, according to Gal 2.11–14, respectively by James and by Cephas.
Stimulated transport of hypoxanthine in Crithidia luciliae:
relationship to purine stress
Authors: DAY R. E. , GERO A. M.
Published: July 2002

Hypoxanthine transport in the insect trypanosome, Crithidia
luciliae, was activated in purine depleted conditions. The existence
of 2 hypoxanthine transport mechanisms was established. The first, a non-saturable
diffusion system, present in purine replete conditions, exhibited properties
that were different from the second transport system which was evident
only during purine depleted conditions (purine stress). The rate of transport
under purine stress was elevated approximately 8-fold over that in replete
conditions. This transporter was saturable with a Km
of 3·9 μM for hypoxanthine. The transporter substrate specificity
included other purine bases, e.g. adenine and guanine, and the purine nucleoside,
adenosine. These inhibited hypoxanthine transport competitively with Ki
values of 2 μM, 3 μM and 42 μM respectively.
Coincident with the increase of hypoxanthine transport under purine stress,
the transport of adenosine increased 4-fold and the activity of the 3′-nucleotidase
ectoenzyme also increased significantly. Under purine stress the concurrent
increase of hypoxanthine and adenosine transport and the increase in 3′-nucleotidase
activity could be repressed with either the supplementation of excess purines
or by cycloheximide. This study of purine salvage mechanisms in Crithidia
luciliae illustrates the successful adaptation of the parasite to
nutritional insufficiency.
The mast cell and eosinophil response of young lambs to a

primary infection with Nematodirus battus
Authors: WINTER M. D. , WRIGHT C. , LEE D. L.
Published: July 2002

Helminthologically naive 8-week-old lambs were administered

50000 infective-stage larvae of the trichostrongyle nematode

Nematodirus battus. Initial mean adult worm burdens were significantly

reduced (P < 0·01) at day 21 post-infection

(p.i.). Peripheral blood eosinophil counts showed a significant increase

(P < 0·001) by day 25 p.i. when compared with

uninfected control animals. Sections of small intestine taken at

post-mortem from the area of adult worm establishment

over the course of infection showed a significant increase in mucosal

eosinophil and mast cell numbers during the period

of adult worm rejection, when compared with uninfected control animals.

These results show that young lambs develop

significant increases in the numbers of cells associated with an

inflammatory reaction in the intestine during the

development of a partially protective immune response to this parasitic
nematode.
Comparison of chromosome and isoenzyme polymorphism
in geographical populations of Leishmania (Viannia) peruviana
Authors: DUJARDIN J. C. , BAÑULS A. L. , DUJARDIN J. P. , AREVALO J. , TIBAYRENC M. , LE RAY D.
Published: July 2002

Five chromosomes and 17 isoenzyme loci were analysed in 4 allopatric
populations of Leishmania (Viannia) peruviana,
and
molecular distances calculated with 2 estimators, Chromosomal Size Difference
Index and Jaccard Distance. Chromosome
and isoenzyme data were in overall concordance: 13/30 isolates clustered
similarly on the dendrograms constructed from
the different estimators, and a significant correlation (P<0·001)
was observed between the molecular distances calculated
from the two sets of characters. This indicates an evolutionary association
between chromosomal size polymorphism and
isoenzymes. Chromosomes have a faster molecular clock than isoenzymes;
twice as many genotypes were identified by
chromosome analysis and significant size differences (for a total of up
to 500 kb for 5 chromosomes together) were observed
within a given zymodeme. Chromosomes most likely represent better indicators
of genetic drift than isoenzymes, as
suggested by the higher correlation between both estimators of chromosomal
size-polymorphism and eco-geography.
Some chromosomes might present an adaptive response to environmental variation.
Density-dependent effects on Anguillicola crassus
(Nematoda) within its European eel definitive host
Authors: ASHWORTH S. T. , KENNEDY C. R.
Published: July 2002

Density-dependent effects on adult and larval stages of the introduced
nematode parasite Anguillicola crassus in the
European eel definitive host were examined in the laboratory in naturally
infected fish, and in field samples. The effect
of adult nematode subpopulations on larval development over time and the
effect of increasing adult intensity on the
gravid female subpopulations were investigated. At high adult subpopulations
the movement of larvae from the swimbladder
wall into the swimbladder lumen appears to be inhibited, and A. crassus
larvae to be arrested in development in
a density-dependent manner. The number of gravid females per host reaches
a constant level, and so the proportion of
gravid female nematodes per adult subpopulation decreases relative to further
increasing total adult nematode numbers.
Both these mechanisms have the potential to regulate infrapopulations of
A. crassus within the eel definitive host and thus
the parasite suprapopulation.
The structure of the monogenean community on the gills
of Pimelodus maculatus in Río de la Plata (Argentina)
Authors: GUTIÉRREZ P. A. , MARTORELLI S. R.
Published: July 2002

The Monogenea fauna was studied from the gills of the catfish Pimelodus maculatus. Fish were caught from Río de la Plata,
in Buenos Aires harbour (Argentina). Five species of Monogenea were found. The structure of the monogenean community
was analysed at the component and infracommunity level. The nature of the monogenean community, its possible
interactivity, seasonal variation and predictability are also discussed.
Studies on phospholipid turnover argue against sloughing
of tegumental membranes in adult Schistosoma mansoni
Authors: BROUWERS J. F. H. M. , SKELLY P. J. , VAN GOLDE L. M. G. , TIELENS A. G. M.
Published: July 2002

The tegumental membrane complex of Schistosoma mansoni is the site of interaction between the parasite and the host.
The tegument is involved in uptake of many nutrients, but also plays a crucial role in the evasion of the actions of the host
immune system. Essential for the success of this evasion is maintaining the integrity of the tegumental membranes. The
rate of turnover of phospholipids was investigated by pulse-labelling worms cultured in vitro, followed by additional
incubation in the presence of unlabelled substrates. Tegumental membranes were isolated, characterized using antibodies
against specific tegumental proteins, and analysed. It was demonstrated that the most prominent fatty acid found in
tegumental phospholipids, palmitate, incorporated rapidly into the phospholipid fraction during a 30 min pulse labelling.
In a subsequent 20 h chase with unlabelled substrates, the incorporated radioactivity was lost again from the tegumental
membrane complex. This high turnover of palmitate was found to be limited to phosphatidylcholine (PC) only. The
turnover was due to deacylation/reacylation, and not to the sloughing of membranes as is the case in schistosomula. It
is speculated that this rapid turnover of PC in the tegument of adult schistosomes plays a new and important role in the
immune evasion by the parasite.
Interaction of Plasmodium gallinaceum ookinetes and
oocysts with extracellular matrix proteins
Authors: ADINI A. , WARBURG A.
Published: July 2002

Plasmodium ookinetes are elongate, motile and invasive while inside the mosquito gut but promptly metamorphose into
spherical immobile oocysts upon coming in contact with the basement membrane surrounding the midgut. There they
begin a prolonged growth period characterized by massive DNA synthesis for the production of sporozoites. Living
Plasmodium gallinaceum ookinetes attached avidly to the murine extracellular matrix proteins, laminin and collagen type
IV. In ELISA-type assays, the main ookinete surface protein, Pgs28 was implicated as a mediator of parasite attachment
to these basement membrane constituents. Laminin and collagen IV adhered to ookinete and oocyst lysates spotted onto
nitrocellulose membranes. Receptor–ligand blot assays demonstrated that Pgs28 and an oocyst-specific antigen recognized
by the mAb 10D6 interact with murine collagen IV and laminin. 10D6 antigen was also recognized by monospecific
antiserum against the human epidermal growth factor receptor. Mosquito-derived laminin was incorporated into oocyst
capsules of P. gallinaceum growing in Aedes aegypti. We hypothesize that contact with the mosquito basement membrane
triggers the transformation of ookinetes into oocysts. Coalescence of basement membrane proteins onto the capsules masks
developing oocysts from the mosquito's immune system and facilitates their prolonged extracellular development in the
mosquito body cavity.
Apoptosis in human Jurkat T cells after culture with live
Taenia crassiceps cysticerci in vitro
Authors: O'CONNELL K. M. , ROGAN M. T.
Published: July 2002

This study examines the effects of Taenia crassiceps cysticerci on the viability of a human T lymphocyte cell line (Jurkat).
Both budding and non-budding T. crassiceps metacestodes were cultured over 24 and 48 h in the presence of Jurkat cells.
Cell viability decreased with increasing numbers of cysticerci, particularly budding cysticerci. Single cell gel electrophoresis
(comet) analysis, which grades DNA damage, showed a significant increase in apoptosis at 24 and 48 h. The
morphology of treated cells was determined using acridine orange with the classical morphology of apoptotic bodies seen
to increase with increasing cysticerci numbers over time. These results indicate that parasite-induced apoptosis occurs
during murine cysticercosis. Such a mechanism may be important in survival of other metacestode infections of medical
or veterinary importance.
Richness and diversity of intestinal metazoan communities
in brown trout Salmo trutta compared to those of eels
Anguilla anguilla in their European heartlands
Authors: KENNEDY C. R. , HARTVIGSEN R. A.
Published: July 2002

The hypothesis that intestinal helminth communities in freshwater brown trout are dissimilar in composition and structure
to those in the European eel was tested by an analysis of component communities from 72 localities and of infracommunities
from 34 localities in the British Isles and Norway. Derived indices were then compared with published data from eels.
Composition of helminth communities differed considerably between the two hosts as a group of 4 species occurred
commonly in trout and so gave greater predictability to the community composition. These 4 species were trout specialists
and in 97% of the localities a trout specialist dominated the community rather than a generalist acanthocephalan as is
typical for eels. By contrast all measures of community structure and indices of richness and diversity indicated that
helminth communities in trout were isolationist in character, species poor and exhibited low diversity at both component
and infracommunity levels. All values of indices for trout helminth communities were strikingly similar to those obtained
from eels. Evidence of interspecific interactions within the trout helminth communities and a limit of 4 to infracommunity
species richness further enhanced the similarities and suggested a common determinant of community structure. The
hypothesis was thus supported in respect of species composition but refuted in respect of community structure.
Characterization, cloning and immunogenicity of antigens released by transforming cercariae of Schistosoma mansoni
Authors: HARROP R. , JENNINGS N. , MOUNTFORD A. P. , COULSON P. S. , WILSON R. A.
Published: July 2002

A schistosome infection is initiated when the parasite penetrates the skin of a susceptible host. Relatively large quantities
of protein are released by transforming cercariae compared to later larval stages. This represents the first parasite material
to which the host's immune system is exposed, yet little is known about the proteins which are released during the first
few hours post-transformation. We have shown that antiserum raised against such molecules was capable of imparting
protection against a schistosome challenge infection upon passive transfer to naïve mice. By screening a cercarial cDNA
library with this serum, 38 positive clones were identified. Sequence analysis showed these to represent 8 different
molecules which included Schistosoma mansoni 21·7 kDa antigen, calcium-binding-protein and the vaccine candidate
glutathione S-transferase (Sm28GST). In addition, 5 clones were isolated, 1 of which had significant homology to many
cytochrome C proteins, another with leukocyte elastase inhibitors and 3 which represented novel molecules. Four clones
were expressed in a prokaryotic high-level expression vector, sera produced against each purified recombinant protein and
used subsequently to probe Western blots and parasite sections. The leukocyte elastase inhibitor homologue and 2
unknowns induced significant proliferation by lymph node cells recovered from mice vaccinated with irradiated cercariae.
More strikingly, the 2 novel proteins stimulated very high levels of interferon γ (IFNγ) secretion both by lymph node cells
and those recovered by broncho-alveolar lavage from the lungs of vaccinated mice. Such results will be discussed in the
context of vaccine development.
Neuroticism and polymorphisms in the serotonin transporter gene
Authors: DEARY I. J. , BATTERSBY S. , WHITEMAN M. C. , CONNOR J. M. , FOWKES F. G. R. , HARMAR A.
Published: July 2002

Background. There is evidence for an association between two different polymorphisms of the
human serotonin transporter gene (5-HTT) and the personality trait of neuroticism and affective
disorder.

Methods. We studied the association between neuroticism and polymorphisms in the 5HTT-linked
promoter region and in a variable number tandem repeat region (VNTR) of the 5-HTT gene in 204
people aged over 60 derived from a random sample of men and women in the general population.
Approximately half of the subjects were in the top 20% of neuroticism scorers and half in the
bottom 20%.

Results. There were no significant differences in allelic or genotypic frequencies between the high
and low neuroticism scorers. There was highly significant linkage disequilibrium between the two
5-HTT gene polymorphisms, and haplotype analysis showed no association between neuroticism
level and haplotype.

Conclusions. Reports of an association between two 5-HTT gene polymorphisms and the
personality trait of neuroticism are not supported by these results.
Bilingual intonation patterns: Evidence of language change
from Turkish-German bilingual children
Authors: Queen Robin M.
Published: July 2002

This article discusses Turkish-German bilingual
children's intonation patterns as they relate to processes
of contact-induced language change. Bilingual speakers
use two distinct rises in both Turkish and German. One
rise (L*HH%) resembles a characteristic German rise, while
the other (L%H%) resembles a characteristic Turkish rise.
The rises pattern pragmatically in ways that are non-normative
for both Turkish and German. Although this pattern is not
clearly attributable to language interference (either borrowing
or shift-induced language change), it is certainly the result
of language contact. Fusion is proposed to account for the
two-way influence between the two languages.
Evaluating dialect in discourse: Teachers' and teenagers'
responses to young English speakers in Wales
Authors: GARRETT PETER , COUPLAND NIKOLAS , WILLIAMS ANGIE
Published: July 2002

School students (15–16 years) in six regions
of Wales were recorded telling stories in their local English
dialects. Some of these narratives were used as samples
representing the main English dialect regions in Wales.
Comparable groups of students (n = 169) and a group of
teachers (n = 47) rated the audio-recorded speakers on
a number of scales of affiliation, status, and Welshness.
Statistical analysis of their ratings, employing cluster
analysis and multidimensional scaling, made it possible
to detect some of the competing or additive effects of
dialect and narrative features. Judgments of “Welshness”
of the speaker/narratives were grounded in the regional
dialect properties; but other judgments, such as the likability
of the speakers, tended to draw on features of both dialect
and narrative. In addition, comparison of students and
teachers revealed differences in their evaluations of particular
dialect communities and the characteristics of the narratives.
The findings illustrate the importance of approaching the
analysis of dialect variation within the broader context
of speech and discourse performance.
Three fallacies
Authors: Adler Jonathan E.
Published: July 2002

Three fallacies in the rationality debate obscure the possibility for reconciling the opposed camps. I focus on how these fallacies arise in the view that subjects interpret their task differently from the experimenters (owing to the influence of conversational expectations). The themes are: first, critical assessment must start from subjects' understanding; second, a modal fallacy; and third, fallacies of distribution.
Is less knowledge better than more?
Authors: Goldman Alvin I.
Published: July 2002

When a distinction is drawn between “total” knowledge and “problem-specific” knowledge, it is seen that successful users of the recognition heuristic have more problem-specific knowledge than people unable to exploit this heuristic. So it is not ignorance that makes them smart, but knowledge.
The horse race to language understanding: FLMP was first out of the gate, and has yet to be overtaken
Authors: Massaro Dominic W.
Published: July 2002

Our long-standing hypothesis has been that feedforward information flow is sufficient for speech perception, reading, and sentence (syntactic and semantic) processing more generally. We are encouraged by the target article's argument for the same hypothesis, but caution that more precise quantitative predictions will be necessary to advance the field.
Is rationality really “bounded” by information processing constraints?
Authors: Klaczynski Paul A.
Published: July 2002

Extremist views on normative rationality fail to address differences in responding owing to intellectual ability or epistemic self-regulation. Individual difference research thus raises serious questions concerning the scientific utility of universal rationality and universal irrationality theories. However, recent data indicate that computational capacity theories do not account adequately for within-subject variability in normative responding, memory-reasoning independence, and instances of ability-normative reasoning independence.
Recognition of continuous speech requires top-down processing
Authors: Stevens Kenneth N.
Published: July 2002

The proposition that feedback is never necessary in speech recognition is examined for utterances consisting of sequences of words. In running speech the features near word boundaries are often modified according to language-dependent rules. Application of these rules during word recognition requires top-down processing. Because isolated words are not usually modified by rules, their recognition could be achieved by bottom-up processing only.
Cooperative versus adversarial communication; contextual embedding versus disengagement
Authors: Stenning Keith , Monaghan Padraic
Published: July 2002

Subjects exhibiting logical competence choices, for example, in Wason's selection task, are exhibiting an important skill. We take issue with the idea that this skill is individualistic and must be selected for at some different level than System 1 skills. Our case redraws System 1/2 boundaries, and reconsiders the relationship of competence model to skill.
The dynamics of embodiment: A field theory of infant perseverative reaching
Authors: Thelen Esther , Schöner Gregor , Scheier Christian , Smith Linda B.
Published: July 2002

The overall goal of this target article is to demonstrate a mechanism for an embodied cognition. The particular vehicle is a much-studied, but still widely debated phenomenon seen in 7–12 month-old-infants. In Piaget's classic “A-not-B error,” infants who have successfully uncovered a toy at location “A” continue to reach to that location even after they watch the toy hidden in a nearby location “B.” Here, we question the traditional explanations of the error as an indicator of infants' concepts of objects or other static mental structures. Instead, we demonstrate that the A-not-B error and its previously puzzling contextual variations can be understood by the coupled dynamics of the ordinary processes of goal-directed actions: looking, planning, reaching, and remembering. We offer a formal dynamic theory and model based on cognitive embodiment that both simulates the known A-not-B effects and offers novel predictions that match new experimental results. The demonstration supports an embodied view by casting the mental events involved in perception, planning, deciding, and remembering in the same analogic dynamic language as that used to describe bodily movement, so that they may be continuously meshed. We maintain that this mesh is a pre-eminently cognitive act of “knowing” not only in infancy but also in everyday activities throughout the life span.
Trading spaces: Computation, representation, and the limits of uninformed learning
Authors: Clark Andy , Thornton Chris
Published: July 2002

Some regularities enjoy only an attenuated existence in a
body of training data. These are regularities whose statistical
visibility depends on some systematic recoding of the data. The
space of possible recodings is, however, infinitely large – it
is the space of applicable Turing machines. As a result, mappings that
pivot on such attenuated regularities cannot, in general, be found by
brute-force search. The class of problems that present such mappings
we call the class of “type-2 problems.” Type-1 problems,
by contrast, present tractable problems of search insofar as the
relevant regularities can be found by sampling the input data as
originally coded. Type-2 problems, we suggest, present neither
rare nor pathological cases. They are rife in biologically realistic
settings and in domains ranging from simple animat (simulated animal
or autonomous robot) behaviors to language acquisition. Not only are
such problems rife – they are standardly solved! This presents
a puzzle. How, given the statistical intractability of these type-2
cases, does nature turn the trick? One answer, which we do not pursue,
is to suppose that evolution gifts us with exactly the right set of
recoding biases so as to reduce specific type-2 problems to
(tractable) type-1 mappings. Such a heavy-duty nativism is no doubt
sometimes plausible. But we believe there are other, more general
mechanisms also at work. Such mechanisms provide general (not
task-specific) strategies for managing problems of type-2 complexity.
Several such mechanisms are investigated. At the heart of each is a
fundamental ploy – namely, the maximal exploitation of states
of representation already achieved by prior, simpler (type-1)
learning so as to reduce the amount of subsequent computational
search. Such exploitation both characterizes and helps make unitary
sense of a diverse range of mechanisms. These include simple
incremental learning (Elman 1993), modular connectionism (Jacobs et
al. 1991), and the developmental hypothesis of “representational
redescription” (Karmiloff-Smith 1979; 1992). In addition, the
most distinctive features of human cognition – language and
culture – may themselves be viewed as adaptations enabling this
representation/computation trade-off to be pursued on an even grander
scale.
Varieties of self-deception
Authors: Bornstein Robert F.
Published: July 2002

Mele's analysis of self-deception is persuasive but it
might also be useful to consider the varieties of self-deception that
occur in real-world settings. Instances of self-deception can be
classified along three dimensions: implicit versus explicit, motivated
versus process-based, and public versus private. All three types of
self-deception have implications for the scientific research
enterprise.
The many faces of self-deception
Authors: Krebs Dennis , Ward J'Anne , Racine Tim
Published: July 2002

Those who invoke the word self-deception to represent one
phenomenon often argue that those who use it to represent another
are misusing the construct. Better to recognize that self-deception
is a fuzzy concept that may be used to represent a variety of mental
processes and states, and to direct our energy toward distinguishing
empirically among its forms and functions.
The uses of self-deception
Authors: Rachlin Howard , Frankel Marvin
Published: July 2002

The essence of a mental event such as self-deception lies
in its function – its place in the life of an animal. But the
function of self-deception corresponds to that of interpersonal
deception. Therefore self-deception, contrary to Mele's thesis,
is essentially isomorphic with interpersonal deception.
The expectancies that govern the P300 amplitude are mostly automatic and unconscious
Authors: Sommer W. , Leuthold H. , Matt J.
Published: July 2002

We argue that probability effects on P300 amplitude are the
product of an automatic frequency detector not subject to voluntary
control and relatively inaccessible to consciousness. “Expectancies”
related to P300 therefore appear to be passive, perceptual ones.
If probability-based expectancies do become conscious, they are
inversely related to P300, supporting the view of Donchin &
Coles (1988).
Achievement: The importance of industriousness
Authors: Eisenberger Robert
Published: July 2002

The emphasis on innate talent as the basis for outstanding
achievement underestimates the importance of hard work. Learned
industriousness helps supply the sustained effort required for
superior achievement. The goal of having a productive, well-educated
citizenry can be furthered by rewarding students for high effort and
attending carefully to their individual educational needs.
More me? Substance concepts and self concepts
Authors: Slater Carol
Published: July 2002

User intentions invoked to account for the distinctive way in
which public-language natural-kind terms gather their extensions
are inapplicable in the case of Millikan's substance concepts.
I suggest that theoretical justification is preferable and available
and raise exploratory questions about the applicability of the notion
of substance concepts to the genesis of self concepts.
An evolutionary model for the learning of language
Authors: Sieratzki Jechil S. , Woll Bencie
Published: July 2002

This commentary deals with the relation between human
language and nonverbal signals used by nonhuman primates. It suggests
that human language could have developed through the interaction of
procedural learning with a preexisting system for socio-affective
communication. The introduction of “content” into existing
“frames” requires a neurobiologically plausible learning
mechanism.
Where and When does the What system play a role in eye movement control?
Authors: Doré-Mazars K.
Published: July 2002

This commentary focuses on Findlay & Walker's model and more specifically, on its underestimation of the role of cognitive processes in eye movement control during complex activities such as text scanning. In particular, the issue of the complexity of the subject's task/behavior is discussed to stress the importance of the link between selection for perceptual processing on the one hand, and the selection of a target for a saccade, on the other. Future models will have to account for the fact that the goal of any saccade is to bring the eyes to a relevant object and that the selection of this saccade target is closely related to object recognition.
The power of cross-linguistic analysis: A key tool for developing explanatory models of human language
Authors: Santelmann Lynn
Published: July 2002

Clahsen's compelling evidence for the dual-mechanism model of the lexicon derives in part from the use of cross-linguistic data in psycholinguistic research. This approach reflects a growing (and positive) trend toward incorporating data from several languages when analyzing and modeling human language behavior. This perspective should be expanded to include data from typologically distinct languages to develop more explanatory models of language.
Perceptual symbols in language comprehension: Can an empirical case be made?
Authors: Zwaan Rolf A. , Stanfield Robert A. , Madden Carol J.
Published: July 2002

Perceptual symbol systems form a theoretically plausible
alternative to amodal symbol systems. At this point it is unclear
whether there is any truly diagnostic empirical evidence to decide
between these systems. We outline some possible avenues of research
in the domain of language comprehension that might yield such evidence.
Language comprehension will be an important arena for tests of the two
types of symbol systems.