bluuebunny/crossref_metadata_2025 huggingface dataset:
Instability of a gravity-modulated fluid layer with surface tension variation
Authors: SKARDA J. RAYMOND LEE
Published: July 2002

Gravity modulation of an unbounded fluid layer with surface tension variations along
its free surface is investigated. The stability of such systems is often characterized in
terms of the wavenumber, α and the Marangoni number, Ma. In (α, Ma) parameter
space, modulation has a destabilizing effect on the unmodulated neutral stability curve
for large Prandtl number, Pr, and small modulation frequency, Ω, while a stabilizing
effect is observed for small Pr and large Ω. As Ω → ∞
the modulated neutral stability
curves approach the unmodulated neutral stability curve. At certain values of Pr
and Ω, multiple minima are observed and the neutral stability curves become highly
distorted. Closed regions of subharmonic instability are also observed. In (1/Ω, g1Ra)-space, where g1 is the relative modulation amplitude, and Ra is the Rayleigh number,
alternating regions of synchronous and subharmonic instability separated by thin
stable regions are observed. However, fundamental differences between the stability
boundaries occur when comparing the modulated Marangoni–Bénard and Rayleigh–Bénard problems. Modulation amplitudes at which instability tongues occur are
strongly influenced by Pr, while the fundamental instability region is weakly affected
by Pr. For large modulation frequency and small amplitude, empirical relations are
derived to determine modulation effects. A one-term Galerkin approximation was also
used to reduce the modulated Marangoni–Bénard problem to a Mathieu equation,
allowing qualitative stability behaviour to be deduced from existing tables or charts,
such as Strutt diagrams. In addition, this reduces the parameter dependence of the
problem from seven transport parameters to three Mathieu parameters, analogous to
parameter reductions of previous modulated Rayleigh–Bénard studies. Simple stability
criteria, valid for small parameter values (amplitude and damping coefficients), were
obtained from the one-term equations using classical method of averaging results.
Scaling exponents in weakly anisotropic turbulence from the Navier–Stokes equation
Authors: GROSSMANN SIEGFRIED , VON DER HEYDT ANNA , LOHSE DETLEF
Published: July 2002

The second-order velocity structure tensor of weakly anisotropic strong turbulence is
decomposed into its SO(3) invariant amplitudes dj(r).
Their scaling is derived within a scaling approximation of a variable-scale mean-field theory of the Navier–Stokes
equation. In the isotropic sector j = 0 Kolmogorov scaling
d0(r) ∝ r2/3 is recovered.
The scaling of the higher j amplitudes (j even) depends on the type of the external
forcing that maintains the turbulent flow. We consider two options: (i) for an analytic
forcing and for decreasing energy input into the sectors with increasing j, the scaling
of the higher sectors j > 0 can become as steep as
dj(r) ∝ rj+2/3;
(ii) for a non-analytic forcing we obtain
dj(r) ∝ r4/3
for all non-zero and even j.
Laboratory studies of equatorially trapped waves

using ferrofluid
Authors: OHLSEN DANIEL R. , RHINES PETER B.
Published: July 2002

We introduce a new technique to model spherical geophysical fluid

dynamics in the

terrestrial laboratory. The local vertical projection of planetary vorticity,

f, varies with

latitude on a rotating spherical planet and allows an important class of

waves in large-scale atmospheric and oceanic flows. These Rossby waves
have

been extensively

studied in the laboratory for middle and polar latitudes. At the equator

f changes sign

where gravity is perpendicular to the planetary rotation. This geometry
has made

laboratory studies of geophysical fluid dynamics near the equator very

limited. We use

ferrofluid and static magnetic fields to generate nearly spherical

geopotentials in a

rotating laboratory experiment. This system is the laboratory analogue
of

those large-scale atmospheric and oceanic flows whose horizontal motions

are governed by the

Laplace tidal equations. As the rotation rate in such a system increases,
waves are

trapped to latitudes near the equator and the dynamics can be formulated
on the

equatorial β-plane. This transition from planetary modes to equatorially
trapped

modes as the rotation rate increases is observed in the experiments. The

equatorial β-plane solutions of non-dispersive Kelvin waves propagating

eastward and non-dispersive Rossby waves propagating westward at low frequency

are observed in the

limit of rotation fast compared to gravity wave speed.
Thermocapillary convection in a cylindrical

liquid-metal floating zone with a strong

axial magnetic field and with a non-axisymmetric heat flux
Authors: MORTHLAND T. E. , WALKER J. S.
Published: July 2002

This paper treats the steady three-dimensional thermocapillary

convection in a

cylindrical liquid-metal zone between the isothermal ends of two

coaxial solid cylinders

and surrounded by an atmosphere. There is a uniform steady magnetic field
which is

parallel to the common centrelines of the liquid zone and solid cylinders,

and there is

a non-axisymmetric heat flux into the liquid's free surface.

The magnetic field is

sufficiently strong that inertial effects and convective heat

transfer are negligible, and

that viscous effects are confined to thin boundary layers adjacent

to the free surface and

to the liquid–solid interfaces. With an axisymmetric

heat flux, the axisymmetric

thermocapillary convection is confined to the thin layer adjacent

to the free surface, but

with a non-axisymmetric heat flux, there is an azimuthal flow

inside the free-surface

layer from the hot spot to the cold spot with the circulation

completed by flow across

the inviscid central core region. This problem is related to the magnetic
damping of

thermocapillary convection for the floating-zone growth of semiconductor
crystals in

Space.
Two-dimensional shock tube flow for dense gases
Authors: BROWN B. P. , ARGROW B. M.
Published: July 2002

Non-stationary oblique shock wave reflections for fluids in the

dense gas regime

are examined for selected cases. A time-accurate predictor-corrector TVD
scheme

with reflective boundary conditions for solving the Euler equations simulates
the

evolution of a wave field for an inviscid van der Waals gas near the thermodynamic

critical point. The simulated cases involve shock tube flows with compressive
wedges

and circular arcs. Non-classical phenomena, such as disintegrating shocks,
expansion

shocks, composite waves, etc., demonstrate significant differences from
perfect gas

flow fields over similar geometries. Detailed displays of wave field structures
and

thermodynamic states for the dense gas flow fields are presented and analysed.
Mixed convection due to a finite horizontal flat

plate embedded in a porous medium
Authors: VYNNYCKY M. , POP I.
Published: July 2002

Simultaneous steady forced and free convective flow past a heated
or

cooled body in a semi-infinite porous medium subject to the Darcy–Boussinesq

approximation is

treated analytically and numerically. A correction term is derived in terms
of the

Rayleigh (Ra) and Péclet (Pe) numbers for the

velocity and temperature fields far

from the body; this is subsequently implemented in a numerical treatment,
using

finite-difference techniques in elliptical coordinates, for

1[les ]Pe[les ]100 and [mid ]Ra[mid ][les ]103.

Flow separation is observed for both heating and cooling, perhaps surprisingly
so

for the former case since the flow near the plate is being accelerated
by comparison

with the forced convection case. A simple analogy with inviscid flow theory
serves

to illustrate the manner in which separation eddies are formed for both
heating and

cooling cases.
Numerical simulation of dynamic contact-line problems
Authors: BAZHLEKOV IVAN B. , SHOPOV PETER J.
Published: July 2002

The presence of a three-phase region, where three immiscible phases

are in mutual

contact, causes additional difficulties in the investigation of many fluid
mechanical

problems. To surmount these difficulties some assumptions or specific hydrodynamic

models have been used in the contact region (inner region). In the present
paper an

approach to the numerical solution of dynamic contact-line problems in
the outer

region is described. The influence of the inner region upon

the outer one is taken into

account by means of a solution of the integral mass and momentum conservation

equations there. Both liquid–fluid–liquid and

liquid–fluid–solid dynamic contact lines

are considered. To support the consistency of this approach tests

and comparisons with

a number of experimental results are performed by means of finite-element
numerical

simulations.
On the stability of vertical double-diffusive

interfaces. Part 3. Cylindrical interface
Authors: ELTAYEB I. A. , LOPER D. E.
Published: July 2002

This is the final part of a three-part study of the

stability of vertically oriented double-diffusive interfaces having

an imposed vertical stable temperature gradient. In this

study, flow is forced within a fluid of infinite extent by a prescribed
excess of

compositionally buoyant material within a circular cylindrical

interface. Compositional

diffusivity is ignored while thermal diffusivity and viscosity are

finite. The instability of

the interface is determined by quantifying the exponential growth rate
of a harmonic

deflection of infinitesimal amplitude. Attention is focused

on the zonal wavenumber of the fastest growing mode.

The interface is found to be unstable for some wavenumber for all values
of the

Prandtl number and interface radius. The zonal wavenumber of the fastest
growing

mode increases roughly linearly with interface radius, except

for small values of the

Prandtl number (<0.065). For small and moderate values of the

radius, the preferred

mode is either axisymmetric or has zonal wavenumber of 1, representing
a helical

instability. The growth rate of the fastest-growing mode is

largest for interfaces having radii of from 2 to 3 salt-finger lengths.
Rheology of dilute suspensions of Brownian
dipolar axisymmetric particles
Authors: ALMOG Y. , FRANKEL I.
Published: July 2002

We study the respective effects of shear rate and of external field
intensity and
direction on the contribution to the bulk stress of Brownian dipolar axisymmetric

particles suspended in a steady macroscopically homogeneous shear flow
of an
incompressible Newtonian fluid. Towards this end we obtain the steady orientational

distribution and make use of existing general dynamic theories of dilute
suspensions.
The calculation focuses on the limit of weak rotary diffusion. Thus, unlike
previous
analyses, the present contribution is not restricted to weak shear effects.

Explicit results are presented for the bulk stress when the external
field acts in the
plane of the simple shear flow. In cases when the deterministic rotary
motion possesses
a single sufficiently stable node a simple unified description of the respective
effects
of both the intensity and azimuthal direction of the external field is
provided by the
boundary-layer approximation. This approximation enables a qualitative
explanation
of existing numerical results as well as furnishing quantitatively accurate
analytical
results at relatively moderate values of the rotary Peclét number
and the Langevin
parameter (∼10). Furthermore, at still larger values of these parameters
use of the
present asymptotic approximation is clearly preferable since the numerical
schemes
rapidly deteriorate when steep orientational gradients appear.

Singularities of the bulk stress are rationalized in terms of the corresponding

deterministic rotary motion. This is particularly interesting because some
of these singular
phenomena (e.g. those associated with an ‘intermediate regime’

of the field intensity
and direction, for which more than one stable attractor exists in the deterministic

problem) have no counterparts in suspensions of dipolar spheres or torque-free

axisymmetric particles.

Finally, the present results obtained for the orientational distribution
are also
applicable to the study of other aspects of the macroscale description
of suspensions of
dipolar axisymmetric particles. In this context we mention the extension
of continuum
modelling of suspensions of swimming micro-organisms so as to enable the
analysis
of fully developed bioconvection.
Quasi-steady vortical structures in vertically vibrating soap films
Authors: VEGA JOSÉ M. , HIGUERA F. J. , WEIDMAN P. D.
Published: July 2002

An analysis of the quasi-steady streaming of the liquid in a vertically
vibrated
horizontal soap film is reported. The air around the soap film is seen
to play a variety
of roles: it transmits normal and tangential oscillatory stresses to the
film, damps
out Marangoni waves, and forces non-oscillatory deflection of the film
and tangential
motion of the liquid. Non-oscillatory volume forcing originating inside
the liquid is
also analysed. This forcing dominates the quasi-steady streaming when the
excitation
frequency is close to the eigenfrequency of a Marangoni mode of the soap
film,
while both volume forcing in the liquid and surface forcing of the gas
on the liquid
are important when no Marangoni mode resonates. Different manners by which
the
combined forcings can induce quasi-steady streaming motion are discussed
and some
numerical simulations of the quasi-steady liquid flow are presented.
Direct numerical simulation of turbulent flows

with cloud-like off-source heating
Authors: BASU A. J. , NARASIMHA R.
Published: July 2002

Direct numerical solutions of the incompressible Navier–Stokes equations have been

obtained under the Boussinesq approximation for the temporal evolution of a turbulent

jet-like flow subjected to off-source volumetric heating, of the kind that occurs in

a cloud due to latent heat release on condensation of water vapour. The results show

good qualitative agreement with available experimental data on spatially growing jets.

Thus, heating accelerates the flow and arrests jet growth; and turbulence velocities

increase with heating but not as rapidly as mean velocities, so normalized intensities

drop. It is shown that the baroclinic torque resulting from the heating enhances the

vorticity dramatically in all three directions, with a preferential amplification at the

higher wavenumbers that results in a rich fine structure at later times in the evolution

of the jet. Streamwise vortex pairs, rendered stronger by mean flow acceleration, appear

to be responsible for large expulsive motions at certain transverse cross-sections

in the ambient fluid near the heated flow; together with the disruption of the toroidal

component of the coherent vorticity achieved by heating, this results in an entraining

velocity field that is qualitatively different from that around unheated turbulent jets.

This mechanism may provide a plausible explanation for the experimentally observed

drop in entrainment with off-source heating.
Stationary vortices in three-dimensional
quasi-geostrophic shear flow
Authors: BURTON G. R. , NYCANDER J.
Published: July 2002

An existence theorem for localized stationary vortex solutions in an external shear
flow is proved. The flow is three-dimensional and quasi-geostrophic in an unbounded
domain. The external flow is unidirectional, with linear horizontal and vertical shear.
The flow conserves an infinite family of Casimir integrals. Flows that have the
same value of all Casimir integrals are called isovortical flows, and the potential vorticity (PV) fields of isovortical flows are stratified rearrangements of one another. The theorem guarantees the existence of a maximum-energy flow in any family of isovortical flows that satisfies the following conditions: the PV-anomaly must have compact support, it must have the same sign everywhere, and this sign must be the same as the sign of the external horizontal shear over the vertical interval to which the support of the PV-anomaly is confined. This flow represents a stationary and localized vortex, and the maximum-energy property implies that the vortex is stable. The PV-anomaly decreases monotonically outward from the vortex centre in each horizontal plane, but apart from this the profile is arbitrary.
The Principle of Phonology-Free Syntax:

four apparent counterexamples in French
Authors: MILLER PHILIP H. , PULLUM GEOFFREY K. , ZWICKY ARNOLD M.
Published: July 2002

The Principle of Phonology-Free Syntax (PPFS) is a

proposed universal principle of

grammar that prohibits reference to phonological information in syntactic
rules or

constraints. Although many linguists have noted phenomena that appear to
them to

be in conflict with it, the appearances are misleading in all cases we
have examined.

This paper scrutinizes four instructive cases in French that

appear to falsify the PPFS.

Section 1 deals with the alleged relevance of syllable count to the description
of

attributive adjective placement; section 2 addresses the validity

of a rule mentioning consonantality in stating the agreement rule for adverbial

tout; section 3 turns to the

issue of preposition choice (e.g. en vs. au)

with geographical proper names; and

section 4 takes a look at a purported case of phonological

reference in stating the rule

for ellipsis of a clitic pronoun and an auxiliary in a

coordinate structure. In each case

we bring independent evidence to bear on the problem in order to show that
the

analyses employing phonology-sensitive syntactic statements are in error
and the

prediction of the PPFS is confirmed.
Temperature relaxation in a parametrically unstable inhomogeneous plasma
Authors: PANCHENKO V. G.
Published: July 2002

On the basis of kinetic fluctuation theory, the relaxation process
between the electron and ion temperatures in a magnetized inhomogeneous
plasma is considered when an external pump wave parametrically decays into
lower-hybrid and electron drift waves. In the region above the instability
threshold, the inverse relaxation time is calculated, and its dependence on the
density gradient and the pump-wave intensity and frequency is obtained. It is
shown that the presence of the parametric instability leads to a decrease of the
relaxation time.
Inhibition of turbulent cascade by sweep
Authors: CHEN SHIYI , KRAICHNAN ROBERT H.
Published: July 2002

The effects of large-scale sweeping velocity on the turbulent
cascade to small
scales are examined for two problems: the advection of a passive scalar
by a
multivariate-Gaussian velocity field and incompressible Alfvén-wave
turbulence.
In both cases, the sweeping produces anisotropy and reduces the
strength of cascade. If the direction of the sweep velocity varies with
time, a
balance is reached between this anisotropy and isotropizing effects associated
with the change of direction.
On the evolution of a nonlinear Alfvén pulse
Authors: VERWICHTE E. , NAKARIAKOV V. M. , LONGBOTTOM A. W.
Published: July 2002

The temporal evolution of weakly nonlinear, plane, linearly polarized
Alfvén pulses in a cold homogeneous plasma is investigated. A static initial
pulse-like disturbance in transverse velocity produces two Alfvén pulses that
travel in opposite directions along the magnetic field. The ponderomotive force
of the two pulses produces a static shock in longitudinal velocity at the starting
position. The travelling pulses form a shock front that is governed by the scalar
Cohen–Kulsrud equation. We find good agreement between the analytical
solutions we derive and the results from a fully nonlinear numerical MHD code.
The subtidal macrobenthos in the mesohaline part of the Schelde Estuary (Belgium): influenced by man?
Authors: Ysebaert Tom , Neve Liesbeth De , Meire Patrick
Published: July 2002

The macrobenthos of the subtidal, mesohaline zone of the Schelde Estuary (Belgium) was sampled in October 1996 and 1997 at 54 and 73 sampling locations respectively. Sediments ranged from silty to very coarse, with the dominant sediment type being silt (33% of all locations). Of the 35 macrobenthic species observed, only seven species occurred in more than 20% of the samples. The polychaete Heteromastus filiformis and Oligochaeta were most common. Multivariate techniques revealed three distinct communities, linked mainly with sedimentological factors: (1) a species-poor (nine species) community with a dominance of the amphipod Bathyporeia pilosa, a low mean abundance and biomass (86 ind m−2, 0.0189 g ash-free dry weight (AFDW) m−2), and a mean median grain size of 215±19 μm (fine sand); (2) a species-rich (22) community, with the small polychaete Polydora ligerica as indicator species, a relatively high mean abundance and biomass (2298 ind m−2, 1.395 g AFDW m−2, oysters excluded), a mean median grain size of 133±41 μm, and also the occurrence of sediments with hard substrates being characteristic for this community; (3) a community with an intermediate species richness (12), abundance and biomass (248 ind m−2, 0.249 g AFDW m−2), with H. filiformis and Oligochaeta as indicator species, and a median grain size of 76±9 μm. In the study area several typical brackish water species were observed (e.g. Polydora ligerica, Corophium lacustre, Gammarus salinus).

Mean total abundance and biomass were very low, and the benthic communities appeared to be under stress, with a dominance of mainly small, subsurface deposit and surface deposit feeding opportunistic species. This is probably a combined effect of both natural physical and human-induced disturbance. Only sediments with hard substrates (e.g. rocks) seems to favour species richness, providing a shelter against physical disturbance.
Hitch-hiking on scallops: grazing avoidance by macrophytes
Authors: Ozolinsh Andris V. , Kupriyanova Elena K.
Published: July 2002

Epibenthic macroalgae were observed to grow more abundantly on the upper surface of the Japanese scallops Patinopecten yessoensis (Bivalvia: Pectinidae) than on other available substrate. A field experiment to examine the hypothesis that colonization of live scallops protects macrophytes from grazing by sea urchins Strongylocentrotus nudus and S. intermedius was performed. Algal growth in the areas with urchins was compared with that in the enclosures without urchins. Each enclosure contained two live scallops, two empty shells, and one rock similar to scallops in size and shape. Twenty live scallops, 16 empty shells and ten rocks were marked and left outside the enclosures. After three months there was no difference in macrophyte mean percentage cover on live scallops inside and outside the enclosures. Percentage cover of macrophytes on dead scallop shells and rocks was significantly lower outside the protective enclosures as compared to unprotected areas. The results support the hypothesis that scallops serve as mobile refugia for macroalgae from urchin grazing.
Inactivity of glycyl-glycyl-arginine and two putative (QSAR) peptide analogues of barnacle waterborne settlement pheromone
Authors: Clare Anthony S. , Yamazaki Mizue
Published: July 2002

The effect of two putative tripeptide analogues (isoleucine-isoleucine-arginine [IIR] and valine-leucine-arginine [VLR]) and a reported analogue, glycyl-glycyl-arginine (GGR), of the waterborne cue to settlement of Balanus amphitrite amphitrite Darwin cypris larvae has been investigated. Settlement in the presence of these tripeptides was not significantly different from that in filtered seawater. Because crude waterborne cue and settlement-inducing protein complex both significantly evoked settlement, the cyprids used in this study were competent to respond. The overall results, therefore, demonstrate that IIR, VLR and GGR are not analogues of barnacle waterborne settlement pheromone.
Shade-seeking behaviour under polarized light by the brittlestar Ophioderma Brevispinum (Echinodermata: Ophiuroidea)
Authors: Johnsen Sönke , Kier William M.
Published: July 2002

The effect of polarized light on the shade-seeking behaviour of the ophiuroid Ophioderma brevispinum was investigated at the Keys Marine Laboratory, Long Key, Florida, USA. Animals were collected and placed in a partially shaded arena. When the arena was illuminated with unpolarized light, the number of animals settling under the shaded portion of the arena was not significantly different from random (N=30, P>0.3). When the arena was illuminated with linearly polarized light, the number of animals settling in the shaded portion of the arena was approximately double what would be expected in a random distribution (N=30, P<0.001). The results are further evidence that O. brevispinum is sensitive to polarized light and are consistent with the hypothesis that polarized light may be used by the animals as an indicator of harmful levels of solar ultraviolet radiation.
LE PÉCHÉ CONTRE L'ESPRIT ANNONCÉ EN LC 12.10, COMMIS EN AC 4.16–18: UNE ILLUSTRATION DE L'UNITÉ DE LUC ET ACTES
Authors: MAINVILLE ODETTE
Published: July 2002

Le rapport de continuité observé dans les développements de thématiques qui se prolongent du troisième évangile au livre des Actes des Apôtres sont des manifestations de l’unité du double ouvrage lucanien. À partir du lien établi entre les contenus de Lc 12.10–12 et d’Ac 4.16–18, cet article démontre: (1) que le rejet par le Sanhédrin du miracle opéré par Pierre et Jean, en Actes, est l’accomplissement de l’annonce du péché contre l’Esprit par Jésus, en Luc; (2) que ce rapport d’accomplissement est un lieu de vérification de l’unité théologique de Luc/Actes.
Monoclonal antibodies multireactive with parasite antigens
produced by hybridomas generated from naive mice
Authors: KONISHI E.
Published: July 2002

Hybridoma clones producing IgM naturally occurring (natural) antibodies
were generated from naive Balb/c mice and
characterized for reactivity against parasite antigens.
Ascites of mice injected with these hybridomas reacted with
Toxoplasma gondii soluble antigen at levels approximately
1000–10000 times higher than serum pooled from mice used
for generating hybridomas as determined by a conventional enzyme-linked
immunosorbent assay. Western blot analysis
indicated that these monoclonal antibodies reacted with multiple antigen
molecules of T. gondii with patterns similar to
that of pooled mouse sera. These antibodies also reacted with
multiple antigens of Plasmodium yoelii, Entamoeba histolytica,
Ascaris lumbricoides, Toxocara canis, Trichuris
vulpis, Fasciola hepatica, Schistosoma mansoni,
and Dipylidium caninum.
When one monoclonal antibody was absorbed with these parasite antigens,
its reactivity with T. gondii antigen molecules
was consistently reduced, independent of parasite species. These natural
antibodies failed to kill T. gondii tachyzoites in
vitro or to protect mice from lethal challenge with T. gondii.
These results indicate that natural antibodies detected in sera
of naive mice are secreted from certain B cell populations and that these
antibodies are multireactive with parasite antigens
and have low affinity.
Status of protozoan genome analysis: trypanosomatids
Authors: BLACKWELL J. M. , MELVILLE S. E.
Published: July 2002

The three trypanosomatid genome projects have employed common strategies which include: analysis of pulsed-field gel
electrophoretic chromosomal karyotypes; physical mapping using big DNA (cosmid, pacmid P1, bacterial artificial
chromosome, yeast artificial chromosome) libraries; partial cDNA sequence analysis to develop sets of expressed sequence
tags (ESTs) for gene discovery and use as markers in physical mapping; genomic sequencing; dissemination of information
through development of web-sites and ACeDB-based fully integrated databases; and establishment of functional genomics
programmes to maximize useful application of genome data. Highlights of the projects to date have been the demonstration
that, despite extensive chromosomal size polymorphisms for diploid homologues within Africa trypanosomes, T. cruzi or
Leishmania, the physical linkage groups for markers on each chromosome are retained across all isolates/species studied
within each group. For African trypanosomes, detailed analysis of chromosome 1 has demonstrated that repetitive
sequences and the two retroposon-like elements RIME and INGI are localized to a defined region at one end of the
chromosome, with the bulk of the central region of the chromosome containing genes coding for expressed proteins.
Comparative mapping shows that, although subtelomeric changes account for a large proportion of the polymorphism in
chromosome size in African trypanosomes, there are significant expansions and contractions in regions across the entire
chromosome. The highlight of the genomic sequencing projects has been the demonstration of just 2 putative transcriptional
units of chromosome 1 of Leishmania major, extending on opposite strands from a point in the central region
of the chromosome. A similar observation made on 93·4 kb of contiguous sequence for T. cruzi chromosome 3 suggests
the presence of promoter and regulatory elements at the junctions of large polycistronic transcriptional units. All data
obtained from the genome projects are made available through the public domain, which has prompted changing
philosophies in how we approach analysis of the biology of these organisms, and strategies that we can employ now in the
search for new therapies and vaccines.
Patterns of Onchocerca volvulus recombinant antigen
recognition in a bovine model of onchocerciasis
Authors: GRAHAM S. P. , WU Y. , HENKLE-DUEHRSEN K. , LUSTIGMAN S. , UNNASCH T. R. , BRAUN G. , WILLIAMS S. A. , McCARTHY J. , TREES A. J. , BIANCO A. E.
Published: July 2002

The antibody responses of 8 cattle experimentally infected with Onchocerca ochengi to 18 recombinant O. volvulus antigens
were measured by ELISA. In addition to establishing antigenic cross-reactivity between the species, the dynamics of
antigen-specific responses were examined to assess how the recognition of the antigens compared to the known stage-specificity of expression. Six cattle responded to all of the antigens and 2 animals responded to all but 1. The dynamics
of the recognition of 4 antigens (B20, MOv-2, MOv-14 and OvNHR2 02E1) were characterized by rapid seroconversion
following infection. Antibody levels to 2 antigens (Ov7 and OvALT-1) increased gradually over the course of infection.
Antibody levels to 4 antigens (OvTPX-2, OvL3Chitinase, Ov103 and Ov9m) reached maximum levels coincident with
the onset of patency. The levels to 3 antigens (OvProalf C50, OvAldolase, Ov39) varied little over the course of infection.
Responses to antigens with functional similarities (OvSOD1, OvSOD2 and OvSOD3 or OvGST1 and OvGST2) showed
comparable temporal profiles. This study demonstrates the high degree of immunological cross-reactivity between the
antigens of O. volvulus and O. ochengi. The immunogenicity of antigens varied over the course of infection in an antigen-specific manner, which not always reflected developmentally regulated expression of the corresponding gene, possibly
owing to cross-reactive epitopes on distinct parasite products.
Detection of Onchocerca volvulus infection in Simulium
ochraceum sensu lato: comparison of a PCR assay and fly
dissection in a Mexican hypoendemic community
Authors: RODRÍGUEZ-PÉREZ M. A. , DANIS-LOZANO R. , RODRÍGUEZ M. H. , UNNASCH T. R. , BRADLEY J. E.
Published: July 2002

Detection of Onchocerca volvulus larvae in vector populations is of prime importance in the assessment of the effectiveness
of onchocerciasis control programmes. Traditionally, detection of larvae is attained by the dissection of flies, but this time-consuming method cannot easily discriminate between species of Onchocerca. The genome of all Onchocerca species has
a unique 150 bp repeat, which can be amplified by PCR, and O. volvulus-specific DNA probes can detect these products
by Southern blot (SB). This study optimizes a PCR/SB assay, and compares it with fly dissection to estimate the prevalence
(p) and intensity of infection (m) in the local vector population of a Mexican community that has become hypoendemic
as a result of 7 years of treatment with ivermectin and nodulectomy. The PCR detected 1 infected fly in a pool of 99
uninfected flies, but the optimal pool size was 50 flies. At the community level, 1 out of 10550 flies was positive
(p=0·0095%, 95% confidence intervals CI=0·00024–07·05280%; m=0·00027 larvae/parous fly, CI=−0·00026–0·00081)
by PCR, and 4 out of 10772 flies (p=0·0371%, CI=0·01012–0.09505%; m=0·00107 larvae/parous fly, 95%
CI=0·00002–0·00212) by dissection (observed m=0·0005). Both methods produce statistically similar estimates of the
prevalence and intensity, indicating that pool screening is a viable alternative for entomological surveillance in areas where
the intensity of transmission is becoming extremely low as a result of control interventions.
Exposure, infection and immune responses to Schistosoma
haematobium in young children
Authors: WOOLHOUSE M. E. J. , MUTAPI F. , NDHLOVU P. D. , CHANDIWANA S. K. , HAGAN P.
Published: July 2002

Behavioural, parasitological and immunological data were obtained from 48 children up to 6 years old, resident in a
Schistosoma haematobium endemic area in Zimbabwe. The children averaged more than 1 contact with infective water
bodies every 3 days and all showed immunological evidence of exposure (an anti-cercarial and/or anti-egg antibody
response). IgM was the dominant isotype and appeared in the youngest children, followed by IgA, IgE and IgG3.
However, only 38 children showed evidence of infection (an anti-egg response or eggs in urine) and only 14 were excreting
eggs. The best estimates from these data are that less than 1 in 100 contacts result in infection and less than 1 in 1000 result
in egg output. This suggests that there may be substantial attrition of invading cercaria even in naïve individuals.
Amazonian onchocerciasis: parasitological profiles by host-age, sex, and endemicity in southern Venezuela
Authors: VIVAS-MARTÍNEZ S. , BASÁÑEZ M.-G. , BOTTO C. , ROJAS S. , GARCÍA M. , PACHECO M. , CURTIS C. F.
Published: July 2002

This paper describes, for the human onchocerciasis focus of southern Venezuela, the age profiles of Onchocerca volvulus
microfilarial (mf) and nodule prevalence, mf intensity, and mf aggregation for the whole examined population (836
Yanomami people) living in 20 villages, and for these communities classified according to endemicity levels (hypoendemic:
[les ] 20%; mesoendemic: 21–59%; hyperendemic: [ges ] 60% infected). Mf prevalence and intensity increased with age,
particularly in the hyperendemic areas, and there were no marked differences between the sexes. The prevalence of nodules
followed the same age pattern. Fifty percent mf prevalence was reached in the 15–19 year age-class when the population
was taken as a whole; nearly in the 10 to 14-year-olds for the hyperendemic level, in those aged 20–29 years in mesoendemic
areas, and not reached at all in hypoendemic villages. The degree of mf aggregation was measured by the k value of the
negative binomial distribution and by the variance to mean ratio (VMR). The relationship between the standard deviation
(S.D.) of mf counts and the mean mf density was also explored. These 3 indices (k, VMR, and S.D.) showed a tendency
to increase with both mean mf load and host age. Since infection intensity and host age were themselves positively related,
it was not possible to draw definite conclusions about age-specific changes of parasite aggregation. There was not a
significant decrease of mf intensity after an earlier peak neither was there a shift towards younger ages of the maximum
no. of mf/mg reached as the endemicity level increased. These results are discussed in relation to detection of density
dependence in the human host, selection of an indicator age-group for rapid epidemiological assessment (REA) methods,
and strategies of ivermectin distribution in the Amazonian focus. It is recommended that, for the Amazonian onchocerciasis
focus, the indicator group for REA consists of all those aged 15 years and over.
Adverse health effects related to mercury exposure from dental amalgam fillings: toxicological or psychological causes?
Authors: BAILER J. , RIST F. , RUDOLF A. , STAEHLE H. J. , EICKHOLZ P. , TRIEBIG G. , BADER M. , PFEIFER U.
Published: July 2002

Background. Possible adverse health effects due to mercury released by amalgam fillings have been
discussed in several studies of patients who attribute various symptoms to the effects of amalgam
fillings. No systematic relation of specific symptoms to increased mercury levels could be established
in any of these studies. Thus, a psychosomatic aetiology of the complaints should be considered and
psychological factors contributing to their aetiology should be identified.

Methods. A screening questionnaire was used to identify subjects who were convinced that their
health had already been affected seriously by their amalgam fillings (N = 40). These amalgam
sensitive subjects were compared to amalgam non-sensitive subjects (N = 43). All participants were
subjected to dental, general health, toxicological and psychological examinations.

Results. The two groups did not differ with respect to the number of amalgam fillings, amalgam
surfaces or mercury levels assessed in blood, urine or saliva. However, amalgam sensitive subjects
had significantly higher symptom scores both in a screening instrument for medically unexplained
somatic symptoms (SOMS) and in the SCL-90-R Somatization scale. Additionally, more subjects
from this group (50% versus 4·7%) had severe somatization syndromes. With respect to
psychological risk factors, amalgam sensitive subjects had a self-concept of being weak and unable
to tolerate stress, more cognitions of environmental threat, and increased habitual anxiety. These
psychological factors were significantly correlated with the number and intensity of the reported
somatic symptoms.

Conclusions. While our results do not support an organic explanation of the reported symptoms,
they are well in accord with the notion of a psychological aetiology of the reported symptoms and
complaints. The findings suggest that self-diagnosed ‘amalgam illness’ is a label for a general
tendency toward somatization.
Kierkegaard on truth as subjectivity: Christianity,

ethics and asceticism
Authors: HAMILTON CHRISTOPHER
Published: July 2002

This paper is an exploration and interpretation of

Kierkegaard's account

of Christian belief. I argue that Kierkegaard believed that

the Christian metaphysical tradition was exhausted and hence

that there could be no defence of belief in

God in purely rational terms. I defend this interpretation

against objections, going

on to argue that Kierkegaard thought it possible to defend

a post-metaphysical

conception of religious belief. I argue that Kierkegaard

thought that such a defence

was available if we understand correctly what it is to speak

with ethico-religious

authority. I argue that, when interpreted in the way I outline,

Kierkegaard's notion

of ethico-religious authority shows his conception of religious

belief to have great

plausibility. However, Kierkegaard goes on to argue that an

individual's true

relationship with God is constituted through the cultivation

of guilt and the sense

of himself as a sinner, and I give reasons for rejecting

this claim, arguing that such

cultivation is a form of asceticism.
The problem of evil and moral indifference
Authors: MAWSON TIM
Published: July 2002

In this paper, I argue that if the libertarian free will defence were seen
to fail because determinism were seen to be true, then another solution to the
problem of evil would present itself. I start by arguing that one cannot, by consideration
of agents' choices between morally indifferent options, reach any conclusion as
to these agents' moral qualities. If certain forms of consequentialism were
false, determinism true, and if there were a God who chose to create this universe,
then His choice would have been between such options. Consideration of the general
nature of the universe God putatively chose to create would not then license any
conclusion as His moral qualities.
Islamic and Christian
heterodox water cosmogonies from the Ottoman period—paralleles
and contrasts
Authors: STOYANOV YURI
Published: July 2002

This article
explores some important parallels and differences between certain
Eastern Christian and Islamic heterodox (Alevi/Kizilbash,
Yezidi and Ahl-e Haqq) cosmogonies, which shared and developed
old cosmogonic themes such as the ‘primal ocean’
and the ‘earth-diver’-demiurge, and co-existed during
the Ottoman period. The investigation reveals that some of the
Eastern Christian versions of these cosmogonies have retained
their archaic forms, but in most of them the earth-diver is
identified with the Devil, a movement towards cosmogonic and
religious dualism that could have been effected by both heretical
and popular Christian diabology. Conversely, despite the existing
traits of dualist and earth-diver cosmogonies in Northern and
Central Asian non-Islamic Turkic and related religious traditions,
a comparative analysis as demonstrated in this article shows
that the Alevi/Kizilbash, Ahl-e Haqq and Yezidi cosmogonies
did not absorb or develop these dualist features but rather
tried to neutralize them by reinterpreting them in a largely
monotheistic framework.
The Impact of Modernisation and Social Policy on Family
Care for Older People in Japan
Authors: KONO MAKOTO
Published: July 2002

In Japan the ideology of familism has reproduced patriarchal family values.
It successfully retained family centred welfare provision and gender
inequality in informal care work, and ensured formal care services were
residual. However, the advancement of modernisation has weakened the
effectiveness of the informal care sector, and the demand for care has
increased steadily along with the ageing of the population. Moreover,
informal care based on the self-sacrifice of family carers tends to be less
popular. This tendency is especially evident in the opinions of the younger
generation and females. Furthermore, structural shifts in their working
circumstances, particularly of females, makes the continuation of the
patriarchal approach to informal care more difficult. In the field of the
care of older people, as part of the strategy for restructuring the Japanese
welfare system, the emphasis is now more on market activities, which is
in accord with the assumptions underlying ‘the residual welfare model of
social policy’ (Titmuss, 1974).
Emergence of a Welfare State – Social Insurance in Sweden in the 1910s
Authors: EDEBALK PER GUNNAR
Published: July 2002

Two important dimensions of the Swedish social insurance system are
those of universality (encompassing the entire population) and of
compensation for loss of income. The decisions basic to the Swedish social
insurance system and thus to the Swedish Welfare State were made
during the 1910s. A universal pension insurance system was decided
upon in 1913. This was the world's first universal public insurance
system. Pensions were provided both in cases of disability and of a person
reaching the age of 67. Important factors explaining this decision were
that Sweden had the oldest population in the Western world and thus
high expenditures for poor relief, and that as the reporting and taxation
of individual incomes had just been introduced it became possible to
finance a universal pension system by means of compulsory contributions
by the individual (a special earmarked tax).

The establishment of a pension insurance system provided the basis for
a system of insurance for work-related injuries, in 1916. It included the
entire workforce and was the most modern of its kind. The presence of a
pension insurance system and insurance for work-related injuries
pointed to the need for a sickness insurance system. This was designed to
deal with simple cases of injury as well as with more serious cases of
illness or injury that could lead to disability. A proposal was presented in
1919. A serious deflationary crisis after the First World War and high
levels of unemployment during the period between the two world wars
made it impossible to introduce a sickness insurance system.
Modeling lexical effects on phonetic categorization and semantic effects on word recognition
Authors: Gaskell M. Gareth
Published: July 2002

I respond to Norris et al.'s criticism of Gaskell and Marslen- Wilson (1997). When the latter's network is tested in circumstances comparable to the Merge simulations in the target article, it produces the desired pattern of results. In another area of potential feedback in spoken word processing, aspects of lexical content influence word recognition and our network provides a simple explanation of why such effects emerge. It is unclear how such effects would be accommodated by Merge.
Multiple personalities and views of neural organization
Authors: Kötter Rolf
Published: July 2002

Neural organization has many facets; multiple descriptive levels and multiple analytical strategies coexist. Although most neuroscientists agree that a multidisciplinary, multistrategic approach is necessary to understand neural organization, diverse individual approaches make it difficult to find the optimal mixture and priority list.
The role of mathematics in heuristic performance
Authors: Kainen Paul C.
Published: July 2002

A mathematical approach to heuristics is proposed, in contrast to Gigerenzer et al.'s assertion that laws of logic and probability are of little importance. Examples are given of effective heuristics in abstract settings. Other short-comings of the text are discussed, including omissions in psychophysics and cognitive science. However, the authors' ecological view is endorsed.
Stipulating versus discovering representations
Authors: Plaut David C. , McClelland James L.
Published: July 2002

Page's proposal to stipulate representations in which individual units correspond to meaningful entities is too unconstrained to support effective theorizing. An approach combining general computational principles with domain-specific assumptions, in which learning is used to discover representations that are effective in solving tasks, provides more insight into why cognitive and neural systems are organized the way they are.
Nightmares: Friend or foe?
Authors: Levin Ross
Published: July 2002

Revonsuo's evolution-based theory places the nightmare as a prototype dream, which fully realizes its biological function. However, individuals who experience both repetitive (PTSD) nightmares and/or lifelong nontraumatic nightmares demonstrate impaired psychological functioning and attenuated information-processing. The importance of reconciling these discrepancies are addressed and ideas for providing stronger empirical tests of the model are presented.

[Revonsuo]
Sexual attractiveness: Sex differences and overlap in criteria
Authors: Townsend John Marshall
Published: July 2002

Women with high sociosexual orientation inventory (SOI) scores may trade signs of willingness to invest for signs of ability to invest, instead of, or in addition to, genetic benefits. The target person's status traits affect women's judgments of sexual/physical attractiveness more than men's. An objective measure of a physical trait such as FA is therefore crucial in untangling the factors affecting women's judgments of attractiveness.
Reducing problem complexity by analogical transfer
Authors: Dominey Peter F.
Published: July 2002

Analogical transfer in sequence learning is presented as an
example of how the type-2 problem of learning an unbounded number
of isomorphic sequences is reduced to the type-1 problem of learning
a small finite set of sequences. The commentary illustrates how the
difficult problem of appropriate analogical filter creation and
selection is addressed while avoiding the trap of strong nativism, and
it provides theoretical and experimental evidence for the existence of
dissociable mechanisms for type-1 learning and type-2
recoding.
LTP and memory: Déjà vu
Authors: Rudy Jerry W. , Keith Julian R.
Published: July 2002

Shors & Matzel's conclusion that LTP is not related
to learning is similar to one we reached several years ago. We discuss
some methodological advances that have relevance to the issue and
applaud the authors for challenging existing dogma.