bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of swept-wing vortices using
nonlinear parabolized stability equations
Authors: HAYNES TIM S. , REED HELEN L.
Published: July 2002

The nonlinear development of stationary crossflow vortices over a 45° swept NLF(2)-0415 airfoil is studied. Previous investigations indicate that the linear stability theory
(LST) is unable to accurately describe the unstable flow over crossflow-dominated
configurations. In recent years the development of nonlinear parabolized stability
equations (NPSE) has opened new pathways toward understanding unstable
boundary-layer flows. This is because the elegant inclusion of nonlinear and non-parallel effects in the NPSE allows accurate stability analyses to be performed without
the difficulties and overhead associated with direct numerical simulations (DNS).
NPSE results are presented here and compared with experimental results obtained at
the Arizona State University Unsteady Wind Tunnel. The comparison shows that the
saturation of crossflow disturbances is responsible for the discrepancy between LST
and experimental results for cases with strong favourable pressure gradient. However,
for cases with a weak favourable pressure gradient the stationary crossflow disturbances
are damped and nonlinearity is unimportant. The results presented here clearly
show that for the latter case curvature and non-parallel effects are responsible for the
previously observed discrepancies between LST and experiment. The comparison of
NPSE and experimental results shows excellent agreement for both configurations.

Through this work, a detailed quantitative comparison and validation of NPSE
with a careful experiment has now been provided for three-dimensional boundary
layers. Moreover, the results validate the experiments of Reibert et al. (1996), and
Radeztsky et al. (1993, 1994) suggesting that their databases can be used by future
researchers to verify theories and numerical schemes. The results show the inadequacy
of linear theories for modelling these flows for significant crossflow amplitude and
demonstrate the effects of weak curvature to be more significant than slight changes
in basic state, especially near neutral-stability locations.
Turbulent thermal convection in a cell with ordered rough boundaries
Authors: DU Y.-B. , TONG P.
Published: July 2002

A novel convection experiment is conducted in a cell with rough upper and lower
surfaces. The measured heat transport in the rough cell is found to be increased by
more than 76%. Flow visualization and near-wall temperature measurements reveal
new dynamics for the emission of thermal plumes. The experiment shows that the
interaction between the horizontal shear flow due to the large-scale circulation and
the ordered rough surface creates a secondary flow (eddies) in the groove region. The
secondary flow together with the large-scale circulation enhance the detachment of
the thermal boundary layer from the tip of the rough elements. These extra thermal
plumes are responsible for the enhanced heat transport in the rough cell. The discovery
of the enhanced heat transport has important applications in engineering for more
efficient heat transfer.
The Architect of the Cuban State: Fulgencio Batista and Populism in
Cuba, 1937–1940
Authors: WHITNEY ROBERT
Published: July 2002

This article examines how Fulgencio Batista y Zaldívar emerged as the
‘strong man’ of Cuba. Historians have pointed out that from 1934 to 1940
Batista's primary support came from the army and the police. We also know that,
like many other Latin American leaders at the time, Batista went through a
‘populist phase’. Populists acknowledged the reality that ‘the masses’ were a new
force in society and that ‘the people’ were at the centre of the nation and the state.
Populist discourse functioned to construct a ‘people’ out of fragmented and
scattered populations. Batista was very aware that in order to rule Cuba he had
to appeal to ‘the people’ and to the revolutionary sentiments of 1933. But we
need more information about exactly what Batista's political ideas were and how
he put them into practice. This article shows how Batista became, in his own
words, the ‘architect’ of the post-revolutionary state between 1937 and 1940.
Batista supervised Cuba's transition from a military dictatorship in 1934 to a
nominal constitutional democracy in 1940. The aim is to shed some light on how
this remarkable transition took place.
Gender and Democratic Politics: A Comparative Analysis of Consolidation in Argentina and Chile
Authors: WAYLEN GEORGINA
Published: July 2002

This article highlights a number of themes useful in the gendered
analysis of democratic consolidation in Latin America by means of a comparative
analysis of Argentina and Chile. It starts from the assumption that much of the
work on democratisation in Latin America – both orthodox and the literature
concentrating on women and transitions – produced up until now, has been too
voluntaristic in its approach. It argues that what is needed, particularly in the
study of democratic consolidation, is an analysis not only of the impact of women
and women's organisations on institutions and structures but also of how these
institutions and structures can shape and change gender relations and different
women's activities. Any gendered analysis of democratic consolidation must
begin by examining the terms of transition which, while they can be subject to
some renegotiation later, affect the nature of the subsequent system and the space
available to different actors. It is argued that a number of characteristics of the
post-transition system are significant: first the impact of more arbitrary populist
or presidential systems, second the importance of women's organising both inside
and outside the state and party systems and third the existence of an
institutionalised party system.
Prelude to an Intervention: Grenada 1983
Authors: WILLIAMS GARY
Published: July 2002

This article examines the demise of the Grenadian

People's Revolutionary Government (PRG) in the summer of 1983 and

the internal power struggle that destroyed the PRG in October that

year, culminating in the execution of Prime Minister Maurice Bishop. A

detailed analysis of events and interactions between Grenada, Barbados

and the United States in the week prior to the crisis period of

19–25 October is provided. I conclude that this pre-crisis

period established the foundations for, and direction of, subsequent

decision-making and explains why a military intervention solution was

chosen and subsequently occurred only five days after Bishop's

death.
A lavoura dos pobres: Tobacco Farming
and the Development of Commercial
Agriculture in Bahia, 1870–1930
Authors: BAUD MICHIEL , KOONINGS KEES
Published: July 2002

The social and economic history of North-Eastern Brazil has largely
been written as the story of slave-holding plantations. In contrast, this article
focuses on the peasant agriculture of tobacco in the state of Bahia. It shows how
the small-scale cultivation of tobacco for the European (mainly German) export
market had already started well before the end of slavery. Tobacco cultivation
gradually expanded to become the most important export product in the first
decade of the twentieth century. Apart from its economic significance, the history
of Bahian tobacco agriculture throws an interesting light on the social and
political relations in the region. Land ownership among the tobacco farmers
expanded, but most of them remained locked into ties of dependency to
commercial intermediaries and large landowners. On the other hand, the latter's
dominant position did not lead to a strong position for tobacco interests in
the regional political arena. Finally, the tobacco producers originated in the black
(ex-)slave community. This article argues that this specific ethnic make-up played
an important role in the organisation of the tobacco sector and its relative neglect
by regional and national politicians.
Presupposition, negation and trivalence
Authors: SEUREN PIETER A. M.
Published: July 2002

Close inspection of presupposition(= P-)cancelling and other metalinguistic negation
data shows that natural language semantics must be (at least) trivalent, with the
values ‘true’, ‘minimally false’ (assertion failure)
and ‘radically false’ (presupposition
failure). It is argued that presupposition is a semantic phenomenon originating in a
distinction between two kinds of satisfaction conditions for predicates, the
PRECONDITIONS generating presuppositions, and the UPDATE CONDITIONS generating
classical entailments. The trivalence of language is a natural consequence of the
acceptance of occasion sentences in an incremental Discourse Semantics. The logical
properties of sentences are considered secondary and derived from their semantic
properties. These include, besides propositional content, a speech act quality,
specifying the personal commitment taken on by the speaker not only in respect of
the propositional content, but also with regard to the linguistic forms selected. It is
suggested that the classical truth-functional operators should be redefined as
instructions under speech act commitment. The negation operator is singled out: it is
redefined as an instruction to reject either an incrementable sentence, which may be
a comment about a form used or to be used (P-preserving negation), or an already
incremented sentence to be removed from the discourse along with some
presupposition (P-cancelling negation).
Temporal dependency and the syntax of subjects
Authors: THOMPSON ELLEN
Published: July 2002

This article explores the interface between the syntactic and semantic representation of natural language with respect to the interpretation of time. The main claim of the paper is that the semantic relationship of temporal dependency requires syntactic locality at LF. Based on this claim, I explore the syntax and semantics of gerundive relative clauses. I argue that since gerundive relatives are temporally dependent on the tense of the main clause, they need to be local with a temporal element of the main clause at LF. I show that gerundive relatives receive different temporal interpretations depending on their syntactic position at LF. This analysis sheds light on the behavior of gerundive relatives in constructions involving coordination, existential there, scope of quantificational and cardinality adverbials, extraposition, presuppositionality effects and binding-theoretic reconstruction effects.
Prosody and melody in vowel disorder
Authors: HARRIS JOHN , WATSON JOCELYNNE , BATES SALLY
Published: July 2002

The paper explores the syllabic and segmental dimensions of phonological vowel
disorder. The independence of the two dimensions is illustrated by the case study of
an English-speaking child presenting with an impairment which can be shown to have
a specifically syllabic basis. His production of adult long vowels displays three main
patterns of deviance – shortening, bisyllabification and the hardening of a target off-glide to a stop. Viewed phonemically, these patterns appear as unconnected
substitutions and distortions. Viewed syllabically, however, they can be traced to a
single underlying deficit, namely a failure to secure the complex nuclear structure
necessary for the coding of vowel length contrasts.
Cross-field plasma acceleration and potential
formation induced by electromagnetic waves
in a magnetized plasma
Authors: SUGAYA R.
Published: July 2002

A single-particle theory is developed to investigate particle acceleration
along and across a magnetic field and the generation of an electric field transverse to
the magnetic field induced by electromagnetic waves in a magnetized plasma. The
almost perpendicularly propagating waves accelerate particles via their Landau
and cyclotron damping, and the ratio of parallel and perpendicular drift velocities
vs∥/vd can be proved to be proportional to k∥/k⊥. Simultaneously, an intense cross-field
electric field E0 = B0×vd/c is generated via the dynamo effect owing to
perpendicular particle acceleration to satisfy the generalized Ohm’s law. This means
that this cross-field particle drift in a collisionless plasma is identical to E×B
drift. It is verified that the transport equations obtained are exactly equivalent to
those derived from the θ-dependent quasilinear velocity-space diffusion equation
obtained from the Vlasov–Maxwell equations.
Viscous drag and the differential rotation of the Earth's core
Authors: BOOK DAVID L. , VALDIVIA J. A.
Published: July 2002

It is proposed that the differential rotation of the Earth's
inner core deduced by
Song and Richards is due to a combination of the deceleration of the Earth's
rotation and the viscous drag between the Earth's inner and outer
cores.
If this model is correct then the dynamic viscosity in the outer core of
the
Earth can be estimated to be μ≈104
poise. Besides providing a novel way of determining
the viscosity of the core, this simple model suggests some new tests and
shows
how astronomical effects can influence geological phenomena.
Wave mixing and instabilities in
cosmic-ray-modified shocks and flows
Authors: WEBB G. M. , ZAKHARIAN A. , ZANK G. P.
Published: July 2002

Wave mixing equations describing the interaction of short-wavelength sound waves
and entropy waves in two-fluid cosmic ray hydrodynamics in a non-uniform, large-scale, background flow in one Cartesian space dimension are investigated. The wave
interaction coefficients depend on large-scale gradients in the background flow, and
consist of two physically distinct components. The first component consists of wave-damping terms due to the diffusing cosmic rays, plus squeezing instability terms
associated with the large-scale cosmic ray pressure gradient. These effects were first
investigated by Drury and Dorfi in a study of the propagation of short-wavelength
WKB sound waves in cosmic-ray-modified flows and shocks. The second component
describes gas dynamical wave mixing effects due to gradients of the gas entropy S
and the gas dynamical Riemann invariants (R±)
of the background flow. A Green
function solution is used to illustrate the coupling of the backward and forward
sound waves for the case of a uniform background flow, in which the coupling
coefficients depend on the parameter α = a2c/2κ,
where ac is the cosmic-ray ‘sound
speed’ and κ is the hydrodynamical cosmic-ray diffusion coefficient. Analytical WKB approximation methods and numerical simulations are used to investigate the modifications of the cosmic ray squeezing instability by wave mixing in cosmic-ray-modified shocks and pressure balance structures. Astrophysical applications to instabilities in supernova remnant shocks are discussed.
Reduction of sheath electric field by
multidielectric slabs in a plasma
Authors: UHM HAN S.
Published: July 2002

The properties of plasma sheaths developed along plasma boundaries
are investigated analytically, assuming that dielectric slabs are present between
electrodes. A collisionless plasma is confined by two planar electrodes. Planar
dielectric slabs with finite thickness partition the plasma into many pieces. The
sheath electric field is inversely proportional to the sum of
2(1+l)+Δ/ελ, where
Δ and ε are the total thickness and the relative dielectric constant respectively
of the dielectric slabs, l is the number of slabs and λ is the Debye length of the
high-density plasma. In this context, the plasma sheaths may easily be
controlled by appropriate choices of dielectric materials and their size.
Feeding of the spider crab Maja squinado in rocky subtidal areas of the Ría de Arousa (north-west Spain)
Authors: Bernárdez C. , Freire J. , González-Gurriarán E.
Published: July 2002

The diet of the spider crab, Maja squinado, was studied in the rocky subtidal areas of the Ría de Arousa (Galicia, north-west Spain), by analysing the gut contents of crabs caught in the summer and winter of 1992. The highly diverse diet was made up primarily of macroalgae and benthic invertebrates that were either sessile or had little mobility. The most important prey were the seaweeds Laminariaceae (43% of the frequency of occurrence and 15% of the food dry weight), Corallina spp. (38% and 3%), molluscs [the chiton Acanthochitona crinitus (15% and 1%), the gastropods Bittium sp. (30% and 2%), Trochiidae and others and the bivalve Mytilus sp. (32% and 12%)], echinoderms [the holothurian Aslia lefevrei (32% and 18%) and the echinoid Paracentrotus lividus (16% and 7%)] and solitary ascidians (18% and 6%). The variability in diet composition was determined by the season (Laminariaceae, Corallina spp., P. lividus, Mytilus sp., gastropods and chitons appeared in greater frequency in winter, while the solitary ascidians and A. lefevrei were consumed to a greater extent in summer) in addition to sexual maturity (prey such as Bittium sp. or Trochiidae were more common in juveniles). Moreover, the changes in the food consumption rate were linked primarily to the moult stage. Feeding activity plummeted during the phases immediately preceding and following ecdysis (stages D0–D3–4 and A), and the diet was less diverse during these phases. No feeding differences were found that could be linked to sex. The composition of the diet of Maja squinado appears to be determined by the seasonal abundance of the different prey in subtidal rocky areas and by their availability (depending on their behavioural and anatomical characteristics, mainly mobility and the presence of hard external structures). Moreover, life history factors have little importance in the variability of the diet composition and only the moult cycle has a considerable effect on feeding rate.
THE CONVERSION OF THE IMAGINATION: SCRIPTURE AND ESCHATOLOGY IN 1 CORINTHIANS
Authors: HAYS RICHARD B.
Published: July 2002

This article argues two major theses: (1) Paul was trying to teach the Corinthian church to think eschatologically; (2) Paul was trying to teach the Corinthian church to reshape its identity in light of Israel's Scripture. These theses entail two important corollaries: (1) the Corinthians did not have an ‘overrealized eschatology’; (2) scholars who contend that Paul engaged in OT interpretation only when his hand was forced by Judaizing opponents cannot explain Paul's rich and varied use of Scripture in 1 Cor. These theses are explained and defended with reference to 1 Cor 10.1–22; 1.18–31 and 5.1–13.
Density dependence in the camelid Vicugna vicugna: the recovery of a protected population in Chile
Authors: Bonacic C. , Macdonald D. W. , Galaz J. , Sibly R. M.
Published: July 2002

The vicuña Vicugna vicugna is a wild South American camelid. Following over-exploitation, which brought the species to the brink of extinction in Chile in the 1960s, the population was protected. Since 1975 the population has been censused annually, generating one of the most extensive long-term census databases for any South American mammal. In this paper we use these data, and measures of environmental parameters, to describe the population growth trend of the species and to estimate carrying capacity. Our results indicate that the vicuña has been protected successfully in northern Chile. The census data reveal that, following protection, the population displayed logistic growth between 1975 and 1992. Population growth rate declined linearly with population size, which indicates a degree of density dependence. Density independent factors, such as rainfall, may also have been important. The principal density dependent effect observed was that birth rate declined in those family groups with the most breeding females. The carrying capacity of the study area was estimated from the census data and from models based on precipitation and local primary productivity. Using the census data, an estimation of carrying capacity as the asymptote of the fitted logistic curve suggested that the vicuña population should reach approximately 26,000 vicuñas, whereas estimation when the population growth rate was equated to zero gave a carrying capacity of c. 22,000. Coe's method based on local precipitation predicted 31,000 vicuña, whereas Lavenroth's method based on local primary productivity predicted 26,000 vicuña. In reality, the census data showed that the population peaked at 22,463 vicuñas in 1990. The results are discussed in relation to the need for better census techniques and the implications of density dependent effects for the management of the vicuña in Chile.
Down-regulation of murine susceptibility to cerebral
malaria by inoculation with third-stage larvae of the
filarial nematode Brugia pahangi
Authors: YAN Y. , INUO G. , AKAO N. , TSUKIDATE S. , FUJITA K.
Published: July 2002

In areas where malaria is endemic, helminthic infections, caused
by
intestinal or filarial parasites, commonly coexist with
malaria in the same individual. This study investigates the course of
Plasmodium berghei malaria infection in CBA/J mice
inoculated with irradiated attenuated 3rd-stage larvae (L3) of Brugia
pahangi. Peripheral eosinophil counts, serum IgE
levels and cytokine production revealed that the filarial antigen induced
T-helper type 2 (Th2) cell predominance in these
mice, which protected them against the development of cerebral malaria.
These
mice significantly prolonged their survival,
compared with the control mice after P. berghei infection. All
of the
mice not inoculated with irradiated L3 died within
12 days with acute neurological manifestations unrelated to the level of
parasitaemia after infection of P. berghei.
Conversely, most of the inoculated mice lived more than 3 weeks following
infection with P. berghei, dying in the fourth
week of severe anaemia and overwhelming parasitaemia. This suggests that
Th2-dominant responses lead to the downregulation of susceptibility to
murine
cerebral malaria.
Cytoskeletal architecture and components involved in the

attachment of Trypanosoma congolense epimastigotes
Authors: BEATTIE P. , GULL K.
Published: July 2002

Scanning and transmission electron microscopy of Trypanosoma

congolense epimastigotes attached to a plastic substratum

shows them to elaborate a complex flagellum filament system and plaque
with

a highly organized structure. Non-ionic

detergent extraction of these cells shows that the resulting cytoskeletons

remain attached to the plaque. The subpellicular

corset of microtubules can be removed by salt or Ca+2

treatment leaving the axoneme, paraflagellar rod, associated filaments

and the plaque. Neither of these treatments therefore removed the

plaque-associated material from the substratum.

Analysis of these fractions by SDS–polyacrylamide gel electrophoresis

reveals an abundant 70 kDa protein that is highly

enriched in the salt extracted ‘minimal plaque’ structures
and

appears likely to be a major constituent of this structure.

These studies reveal that the complex filament and microtubule systems
of

the cytoskeleton involved the attachment of

trypanosomes to substrata and have established a method of biochemical

fractionation of the structures and components involved.
Immunological enhancement of breast cancer
Authors: STEWART T. H. M. , HEPPNER G. H.
Published: July 2002

Breast cancer is a complex disease. Its aetiology is multifactorial,

its period of development can span decades, and its
clinical course is highly variable. Evaluation of the role of the immune

response in either the development or control of
breast cancer is also complex. Nevertheless, there is substantial information

that in this disease, the immune response is
not a host defence reaction and may even serve to facilitate cancer development.

This evidence comes from a variety of
sources including clinical–pathological investigations in women that

show a correlation between the intensity of lymphocytic infiltration into

the tumour mass with poor prognosis, studies in breast cancer patients

that demonstrate a similar
correlation between delayed hypersensitivity reactivity or in vitro

assays of immune reactivity to tumour cell membranes
or non-specific antigens and poor prognosis, and analyses of cancer
incidence in chronically immunosuppressed, kidney
transplant recipients who develop an unexpectedly low incidence of breast

cancer. The overall conclusions from these
human studies are corroborated by observations in mouse mammary tumour

models that also demonstrate immune
enhancement of breast cell proliferation in vitro and of breast

cancer development in vivo. Potential mechanisms for these
effects include production, by inflammatory cell infiltrates, of direct

or indirect modulators of breast cell growth, e.g.
cytokines, peptide or steroid hormones, enzymes involved in steroid
metabolism, as well as of antibodies to growth factors
or their receptors. These immune facilitatory mechanisms must be overcome

if immune-based therapies are to be applied successfully in breast cancer.
Differences and similarities between Trichinella spiralis
and T. pseudospiralis in morphology of stichocyte granules,
peptide maps of excretory and secretory (E–S) products
and messenger RNA of stichosomal glycoproteins
Authors: WU Z. , NAGANO I. , TAKAHASHI Y.
Published: July 2002

The ultrastructure of muscle larvae of Trichinella
pseudospiralis was studied by electron microscopy. The overall
structure of muscle larvae of T. pseudospiralis resembled
that of T. spiralis except for the stichocyte granules.
T. pseudospiralis had
at least 3 kinds of stichocyte granules distinguishable from each
other by their shape, size and inclusions. The granules
had some resemblance to α granules or β granules of
T. spiralis, but no resemblance to γ granules. In favour
of these morphological differences and similarities among
T. spiralis and T. pseudospiralis, excretory and
secretory (E–S) products
(originating from stichocyte granules) of the 2 species differed to
some degree. In an analysis by 2-dimensional
electrophoresis, some peptide spots migrating at 45 kDa were shared
by the 2 species but the other spots were unique to
each of the 2 species. Messenger RNA encoding the 43 kDa glycoprotein
of stichocyte granules was detected in the muscle
larvae of both species but mRNA encoding the 53 kDa glycoprotein
was detected only in muscle larvae of T. spiralis.
Characterization of trypanosome infections by polymerase
chain reaction (PCR) amplification in wild tsetse flies in Cameroon
Authors: MORLAIS I. , GREBAUT P. , BODO J. M. , DJOHA S. , CUNY G.
Published: July 2002

The polymerase chain reaction (PCR) method was used to characterize

trypanosome infections in tsetse flies from 3
sleeping sickness foci in Cameroon. The predominant tsetse species found
was
Glossina palpalis palpalis. An average
infection rate of 12·1% was revealed by microscopical examination
of
888 non-teneral tsetse flies. PCR amplification
analyses for trypanosome identification were carried out on 467 flies,

with primer sets specific for Trypanosoma (Trypanozoon)

brucei s.l., T. (Duttonella) vivax,

T. (Nannomonas) simiae and forest type
T. (Nannomonas) congolense. Of 467 flies
93 were positive by microscopical analysis while PCR succeeded in identifying

89 positive flies. Of the PCR-positive flies
34 (38·2%) were negative by microscopical examination. PCR
amplification, when compared to the parasitological
technique, gave a higher estimate of infection rate of trypanosomes in

natural tsetse populations. The PCR technique did,
however, fail to identify 40·9% (38/93) of the
parasitologically positive flies. The reasons for this failure are discussed.

The overall prevalence of mixed infections, assessed by PCR, was 37·1%;

the majority (72·7%) involved T. brucei and
forest type T. congolense.
The opercular bond in the egg-shell of the monogenean
Entobdella soleae, a platyhelminth skin parasite of the
common sole (Solea solea)
Authors: KEARN G. C. , EVANS-GOWING R. , TAPPENDEN T.
Published: July 2002

The monogenean (platyhelminth) skin parasite Entobdella soleae
from the common sole (Solea solea) lays tetrahedral eggs.
One of the 4 corners of the tetrahedron is a detachable operculum which
is bonded to the rest of the egg-shell by cement.
Most of this cement layer, beginning at the inner surface of the shell
and running through almost to the outer surface (a
distance of about 2 μm), is more or less uniform in thickness (30–38
nm), or tapers slightly. About 345 nm from the outer
surface the cement layer narrows abruptly to about 10 nm. The cement is
exposed on the inner surface of the shell, but
in most eggs a layer of shell about 10 nm thick covers the narrow outer
region of the cement layer. When experimentally
perforated eggs were incubated with trypsin, the wide inner layer of cement
was digested, but the narrow outer region
initially remained intact. These observations are discussed in relation
to the following (1) survival of the eggs during
embryonic development, (2) hatching, (3) the ‘hinge’ often
connecting the operculum to the empty egg-shell, (4) the
rapid hatching that occurs in some other monogeneans.
The immune response and the evaluation of acquired
immunity against gastrointestinal nematodes in cattle:
a review
Authors: CLAEREBOUT E. , VERCRUYSSE J.
Published: July 2002

The present review discusses the immune responses to gastrointestinal nematodes in cattle and the different immunological
and parasitological parameters used to assess acquired immunity. Measuring acquired immunity to gastrointestinal
nematodes in cattle (e.g. for the evaluation of candidate parasite vaccines) is hampered by the limited understanding of
bovine immune responses against gastrointestinal parasites. In this paper the available data on protective immunity against
gastrointestinal nematodes, and especially Ostertagia ostertagi, in cattle are compared with the current knowledge of
protective immune responses against gastrointestinal nematodes in rodent models and small ruminants. In contrast to the
immune response in mice, which is controlled by T helper 2 (Th2) lymphocytes and results in mast cell- or goblet cell-
mediated expulsion of adult worms, bovine immune responses to O. ostertagi do not show a clear Th2 cytokine profile,
nor do they result in rapid expulsion of the parasite. The first manifestation of immunity to O. ostertagi in calves is a
reduction of worm fecundity, possibly regulated by the local IgA response. Worm numbers are only reduced after a
prolonged period of host–parasite contact, and there are indications that O. ostertagi actively suppresses the host's immune
response. Until the mechanisms of protective immunity against O. ostertagi are revealed, the use of immunological
parameters to estimate acquired immunity in cattle is based on their correlation with parasitological parameters and on
extrapolation from rodent and small ruminant models. Assessing the resistance of calves against a challenge infection by
means of parasitological parameters is probably still the most accurate way to measure acquired immunity against
gastrointestinal nematodes.
Chronic Plasmodium falciparum infections in an area of low
intensity malaria transmission in the Sudan
Authors: HAMAD A. A. , EL HASSAN I. M. , EL KHALIFA A. A. , AHMED G. I. , ABDELRAHIM S. A. , THEANDER T. G. , ARNOT D. E.
Published: July 2002

Chronic Plasmodium falciparum malaria infections in a Sudanese village, in an area of seasonal and unstable malaria
transmission, were monitored and genetically characterized to study the influence of persistent infection on the immunology
and epidemiology of low endemicity malaria. During the October–December malaria season of 1996, 51 individuals
out of a population of 420 had confirmed and treated P. falciparum malaria in the village of Daraweesh in eastern Sudan.
In a cross-sectional survey carried out in December 1996, an additional 6 individuals were found to harbour a microscopically
negative but polymerase chain reaction (PCR)-positive P. falciparum infection. On 1 January 1997, a cohort
of 43 individuals aged from 9 to 53, recruited from this group of recently malaria-infected individuals agreed to donate
fortnightly blood samples for the next 9 months, the first 6 of which constitute the long Sudanese dry season when
transmission falls to undetectable levels. Each blood sample was tested for the presence of persistent malaria infection by
microscopy and PCR. Parasite-positive samples were genotyped using PCR assays that detect allelic polymorphism at the
MSP-1, MSP-2 and GLURP marker gene loci. Of 43 individuals 16 were found to maintain chronic P. falciparum
infections which were continuously genetically characterized.
Transmission of Orientia tsutsugamushi, the aetiological
agent for scrub typhus, to co-feeding mites
Authors: FRANCES S. P. , WATCHARAPICHAT P. , PHULSUKSOMBATI D. , TANSKUL P.
Published: July 2002

Experiments were conducted to investigate the potential for transmission of Orientia tsutsugamushi, the aetiological agent
for scrub typhus, when naturally infected mite larvae were co-feeding with uninfected larvae. Larvae from colonies of
Leptotrombidium deliense and L. imphalum infected with O. tsutsugamushi were used. Transmission of O. tsutsugamushi to
previously uninfected L. deliense and Blankaartia acuscutellaris co-fed with infected L. deliense was shown to occur. The
overall minimum rate of acquisition was 1·6% (4/258) for L. deliense and 2·5% (3/119) for B. acuscutellaris. When
individual infected L. deliense were co-fed with B. acuscutellaris acquisition of O. tsutsugamushi was not detected. However,
when 4 and 8 infected larvae were co-fed with B. acuscutellaris acquisition of O. tsutsugamushi was detected. Transmission
of O. tsutsugamushi was not observed when uninfected L. deliense were co-fed with infected L. imphalum. This novel
transmission route may explain the occurrence of rickettsiae in genera other than Leptotrombidium spp, which are
considered to be the main vectors of O. tsutsugamushi.
BRIEF COMMUNICATION.
Authors: SELZER ROB , CARLIN JOHN B.
Published: July 2002

Unless positive responses are verified at a
second stage of data collection, a
questionnaire-based survey has limited ability to assess change in caseness
in a longitudinal study
of a condition of low prevalence, assuming imperfect validity of the survey
instrument.
Predictors of mental health service costs for

representative cases of psychosis in south London
Authors: McCRONE P. , THORNICROFT G. , PARKMAN S. , NATHANIEL-JAMES D. , OJURONGBE W.
Published: July 2002

Background. Increasingly, evaluations of mental health

services include an economic component,

although often only summary statistics such as the mean or median

are reported. Measures of

variation are often limited to the standard error or standard deviation,

though costs are rarely

normally distributed and vary substantially between patients. The

aim of this study is to identify

factors that can explain variations in the cost of mental health

services for epidemiologically representative cases of psychosis.

Methods. Cases with ICD-10 diagnoses of functional

psychosis were drawn from a sample that

included all identified cases of psychosis in two geographically

defined sectors in Camberwell, south

London. Mental health service use was measured and costed. A

predictive model was developed

using multiple regression analyses, in which patient characteristics

and previous service use

indicators were used as predictor variables. Services were measured

using the Client Service Receipt Interview.

Results. Among the 147 cases included, the amount of cost

variation explained by the model was

31·5%. The most significant predictive factor was social

functioning, which was highly negatively associated with cost.

Conclusions. Current mental health service use can be

predicted to a reasonable extent by previous

service use and patient characteristics, especially the degree of

social disability. Identification of such

factors can aid the effective allocation of scarce resources. In

particular, subgroups of patients who

use most resources can be identified and targeted by mental health services.
Lower serum activity of prolyl endopeptidase in
fibromyalgia is related to severity of depressive
symptoms and pressure hyperalgesia
Authors: MAES M. , LIBBRECHT I. , VAN HUNSEL F. , LIN A.-H. , BONACCORSO S. , GOOSSENS F. , De MEESTER I. , De CLERCK L. , BIONDI M. , SCHARPE S. , JANCA A.
Published: July 2002

Background. The aims of the present study were
to examine serum activities of peptidases, i.e.
prolyl endopeptidase (PEP) and dipeptidyl peptidase IV (DPP IV), in patients
with fibromyalgia
and to examine the effects of subchronic treatment with sertraline on these
variables.

Method. Serum PEP and DPP IV activity were measured in 28 normal
volunteers and 21
fibromyalgia patients, classified according to the American College of
Rheumatology criteria.
Tenderness at tender points was evaluated by means of dolorimetry. Fibromyalgia
patients had
repeated measurements of serum PEP and DPP IV both before and after repeated
administration
of sertraline or placebo for 12 weeks.

Results. Patients with fibromyalgia had significantly
lower serum PEP activity than normal
volunteers. There were significantly negative correlations
between serum PEP activity and severity
of pressure hyperalgesia and the non-somatic, cognitive symptoms of the
Hamilton Depression
Rating Scale. Fibromyalgia patients with severe pressure
hyperalgesia had significantly lower PEP
activity than normal controls and fibromyalgia patients with
less severe hyperalgesia. Fibromyalgia
patients with severe non-somatic depressive symptoms had significantly
lower serum PEP activity
than normal volunteers. There were no significant changes in serum DPP
IV activity in
fibromyalgia. There were no significant effects of repeated
administration of sertraline on serum
PEP and DPP IV activity in patients with fibromyalgia.

Conclusions. The results show that fibromyalgia, and aberrant

pain perception and depressive
symptoms in fibromyalgia are related to lower serum PEP activity. It is
hypothesized that lower
serum PEP activity may play a role in the biophysiology of fibromyalgia
through diminished
inactivation of algesic and depression-related peptides.
Homeless youth in London: I. Childhood
antecedents and psychiatric disorder
Authors: CRAIG T. K. J. , HODSON S.
Published: July 2002

Background. There has been an increase in the numbers
of homeless young people in Britain. Little
is known of the health and social welfare needs of this population.

Method. This case–control study compares a random sample
of homeless people aged under 22
years recruited from consecutive attenders at two of London's largest
facilities for homeless young
people with a contemporaneous sample of domiciled young people recruited
through general
practice registration lists. The homeless and domiciled groups were compared
on measures of
childhood care, education and psychiatric disorder.

Results. One hundred and sixty-one homeless people (88% of those
approached) and 107 domiciled
subjects (60% of those approached) were interviewed. Sixty-nine per cent
of homeless and a third
of the domiciled subjects reported a childhood lacking in affection, with
indifferent and often violent
carers. Psychiatric disorder was identified in 62% of homeless respondents
and a quarter of the
domiciled population. A fifth of homeless and 5 domiciled respondents had
attempted suicide in the
previous year. Multivariate analysis suggest that childhood adversity,
low educational attainment
and the prior presence of psychiatric disorder all independently increase
the likelihood of
homelessness in a youthful population.

Conclusions. The evidence presented in this paper supports
the hypotheses that characterize the
young homeless population as experiencing higher rates of childhood adversity
and psychiatric
disorder than their domiciled contemporaries. A tentative model is suggested
whereby childhood
experiences, educational attainment and the prior presence of psychiatric
disorder all independently
increase the likelihood of homelessness in a youthful population.
Panic disorder following torture by suffocation is associated with

predominantly respiratory symptoms
Authors: BOUWER COLIN , STEIN DAN
Published: July 2002

Background. We previously reported that in panic disorder
a history of near-suffocation is
associated with predominantly respiratory panic attacks. It might be hypothesized
that the
near-suffocation experienced in certain kinds of torture is also associated
with the development of
predominantly respiratory panic attacks.

Methods. A sample of patients who had experienced torture (N=14)
was drawn from an Anxiety
Disorders Clinic in South Africa. Subjects were questioned about symptoms
of panic disorder, post-traumatic stress disorder and depression.

Results. Patients with a history of torture by suffocation
were more likely than other patients to
complain of predominantly respiratory symptoms during panic attacks. These
patients also
demonstrated higher levels of depressive symptoms.

Conclusions. While various interpretations of the data can
be made, it is possible that torture by
suffocation is associated with a specific symptomatic profile. Were such
an association to be
replicated, this would perhaps support the suffocation alarm hypothesis
of panic disorder and
provide evidence that specific environmental factors play a role in the
development of this alarm.
The association between the high interpersonal sensitivity type of
personality and a lifetime history of depression in a sample of
employed Japanese adults
Authors: SAKADO K. , SATO T. , UEHARA T. , SAKADO M. , KUWABARA H. , SOMEYA T.
Published: July 2002

Background. Although the ‘high interpersonal sensitivity’ type of personality has repeatedly been
shown to be related to depression by case–control studies, no studies have confirmed whether this
association also exists in a non-clinical sample.

Methods. Scores on the Interpersonal Sensitivity Measure (IPSM) were compared between
employed Japanese adults with and without a lifetime diagnosis of major depressive disorder. The
diagnosis was provided by the Inventory to Diagnose Depression, Lifetime version. A multiple
logistic regression analysis estimated the odds ratios for having a lifetime diagnosis of depression.

Results. The scores on the IPSM were higher in the subjects with a lifetime history of depression
than those without a lifetime history of depression. On the five subscales of the IPSM, the subjects
with a lifetime history of depression showed higher scores on ‘interpersonal awareness’, ‘need for
approval’, and ‘separation anxiety’ than those without a lifetime history of depression. The
multiple logistic regression analysis showed that the subjects with the high interpersonal sensitivity
type of personality had an increased risk for experiencing lifetime depression.

Conclusions. The results suggest that high interpersonal sensitivity is a risk factor for depression
even in a non-clinical sample from non-Western culture.
The Mental Adjustment to Cancer (MAC) Scale:
replication and refinement in 632 breast cancer
patients
Authors: OSBORNE R. H. , ELSWORTH G. R. , KISSANE D. W. , BURKE S. A. , HOPPER J. L.
Published: July 2002

Background. Assessment of adjustment of patients in cancer treatment trials is becoming more
common and increasingly regarded as a useful outcome measure. The widely used Mental
Adjustment to Cancer (MAC) Scale was designed to measure Fighting Spirit (FS), Anxious
Preoccupation (AP), Helpless–hopelessness (HH) and Fatalism.

Methods. Questionnaire responses from 632 breast cancer patients were randomly divided into two
groups, one for exploratory analyses and possible scale refinement, and the other for validation
purposes.

Results. Estimates of reliability (Cronbach's α) were satisfactory for two scales, FS (α = 0·85) and
HH (α = 0·81), but lower for AP (α = 0·65) and Fatalism (α = 0·64). Exploratory factor analysis
suggested that the MAC Scale might be measuring six independent constructs including two related
to Fighting Spirit (Positive Orientation to the Illness, Minimizing the Illness), two related to
Fatalism (Fatalism-revised, Loss of Control), a construct we have named Angst, and an unchanged
HH construct. Scales developed to measure these constructs were satisfactorily replicated in
confirmatory analyses but some reliabilities were lower than desirable. The general structure of the
MAC Scale remained little changed despite the division of two scales and the suggested removal of
six items. The refined scales correlated with the Hospital Anxiety and Depression scale and the
Medical Coping Modes Questionnaire, indicating good concurrent validity.

Conclusions. While reasonable reliability of the original scales persists through analyses of the
MAC Scale, the original factor structure could not be reproduced. Six refined constructs with strong
construct validity were identified within the overall domain of mental adjustment to cancer.
Linguistic processing in high-functioning adults with autism or Asperger's syndrome. Is global coherence impaired?
Authors: JOLLIFFE THERESE , BARON-COHEN SIMON
Published: July 2002

Background. Linguistic processing was explored in normally intelligent adults with either autism or Asperger's syndrome, to test if global coherence was impaired. Global coherence is the ability to establish causal connections and interrelate local chunks into higher-order chunks so that most linguistic elements are linked together thematically. Since individuals with autism are hypothesized to have weak central coherence then one would predict that the clinical groups would have difficulty integrating information globally so as to derive full meaning.

Methods. Two experiments were designed to test global coherence. Experiment 1 investigated whether individuals on the autism spectrum condition could arrange sentences coherently. Experiment 2 investigated whether they were less able to use context to make a global inference.

Results. The clinical groups were less able to arrange sentences coherently and use context to make a global inference.

Conclusions. The results suggest that individuals on the autism spectrum have impaired global coherence. Arranging sentences and making global inferences correlated highly, suggesting that central coherence may be a unitary force in these different tasks. Of the two clinical groups, the autism group had the greater deficit. The effect that such a deficit would have on one's daily life is discussed, along with possible explanations for the clinical groups' greater difficulty, and suggestions for future research.
The relationship of childhood sexual abuse and depression with somatic symptoms and medical utilization
Authors: NEWMAN M. G. , CLAYTON L. , ZUELLIG A. , CASHMAN L. , ARNOW B. , DEA R. , TAYLOR C. B.
Published: July 2002

Background. Previous research suggests that childhood sexual abuse is associated with high rates of retrospectively reported medical utilization and medical problems as an adult. The goal of this study was to determine if abused females have higher rates of medical utilization using self-report and objective measures, compared with non-abused females. A further goal was to determine whether findings of prior research would be replicated when childhood physical abuse level was controlled. This study also examined the moderating impact of depressed mood on current health measures in this population.

Methods. Six hundred and eight women recruited from a health maintenance organization completed self-report measures of health symptoms for the previous month and doctor visits for the previous year. Objective doctor records over a 2 year period were examined for a subset of 136 of these women.

Results. Results showed significantly more self-reported health symptoms and more self-reported doctor visits in abused participants compared with those who reported no childhood history of sexual abuse. Objective doctor visits demonstrated the same pattern with abused participants exhibiting more visits related to out-patient surgery and out-patient internal medicine. In addition, persons who were both sexually abused and depressed tended to visit the emergency room more frequently and to have more in-patient internal medicine and ophthalmology visits than sexually abused participants who reported low depressed mood and non-abused controls.

Conclusions. These results replicate prior studies and suggest that current depression may moderate the relationship between sexual abuse and medical problems in adulthood.