bluuebunny/crossref_metadata_2025 huggingface dataset:
Pathbreaking verbs in syntactic development and the
question of prototypical transitivity
Authors: NINIO ANAT
Published: July 2002

The first verbs to participate in VO and SVO combinations, and the
temporal parameters of the spread of these combinatory patterns over
different verbs were investigated. The longitudinal language observations of
16 children, one acquiring English, the others Hebrew, were
examined. The children were observed once a week for 3–12 months, the
observations starting when the children were still in the single-word
stage (1;1–2;1) and ending when they were well into multiword speech
(1;8–2;7). The results indicate that the more verbs children already
know to combine in a certain pattern, the faster they learn new ones.
Apparently children induce from individual word-combinations some
general principles that facilitate further learning. The ‘pathbreaking
verbs’ that begin the acquisition of a novel syntactic rule tend to be
generic verbs expressing the relevant combinatorial property in a
relatively pure fashion: the same verbs that children first combine with
direct objects, are typical grammaticalized markers of transitivity in
many languages. These verbs do not have HIGH TRANSITIVITY as defined
by Hopper & Thompson (1980). Rather, they express fundamental
‘object relations’ of incorporation into, and ejection from the personal.
Crosslinguistic evidence indicates that this may be the basic transitivity
construct in languages. The results raise the possibility that lexical-specific learning of positional patterns is sufficient to account for the
formation of syntactic abstractions.
Multi-symplectic structures and wave propagation
Authors: BRIDGES THOMAS J.
Published: July 2002

A Hamiltonian structure is presented, which generalizes classical
Hamiltonian structure,
by assigning a distinct symplectic operator for each unbounded space direction
and time, of a
Hamiltonian evolution equation on one or more space dimensions. This generalization,
called
multi-symplectic structures, is shown to be natural for dispersive wave
propagation problems.
Application of the abstract properties of the multi-symplectic structures
framework leads to
a new variational principle for space-time periodic states reminiscent
of the variational
principle for invariant tori, a geometric reformulation of the concepts
of action and action
flux, a rigorous proof of the instability criterion predicted by the Whitham
modulation
equations, a new symplectic decomposition of the Noether theory, generalization
of the concept
of reversibility to space-time and a proof of Lighthill's geometric
criterion for
instability of periodic waves travelling in one space dimension. The nonlinear
Schrödinger
equation and the water-wave problem are characterized as Hamiltonian systems
on a multi-symplectic
structure for example. Further ramifications of the generalized symplectic
structure of
theoretical and practical interest are also discussed.
A note on powers in simple groups
Authors: SAXL JAN , WILSON JOHN S.
Published: July 2002

In [7], the second author proved that there
is an integer k such that every element
of a finite non-abelian simple group S is a product of
k commutators in S. The
motivation for proving this result came from a model-theoretic question
about
simple groups. The proof depended on the classification of the finite simple
groups,
a theorem of Malle, Saxl and Weigel [5] which shows
that in many finite simple
classical groups S there is a real conjugacy class R
such that S=R3∪{1}, and an
ultraproduct argument. Here we shall use a similar combination of ideas
to prove the
following result.
Rational tangle distances on knots and links
Authors: DARCY ISABEL K. , SUMNERS DE WITT
Published: July 2002

In order to model biological reactions, distances between knots/links based on
tangle replacement are defined. Given a tangle R, an R-move is defined as the replacement
of the zero tangle in a link L with the tangle R. The R-distance between
the link L and the link M is defined to be the minimum number of R-moves required
to change L into M where the minimum is taken over all diagrams of the link L.
A formula is given to determine when one 4-plat knot/link can be obtained from
another 4-plat via one R-move when R is a rational tangle and not equal to the
1/n tangle. The formula can also be used to find all rational tangles R for which the
R-distance between two given 4-plats is 1 except in the case R = 1/n tangle. These
results are also generalized to the case when any rational tangle P is replaced with
any rational tangle R, P not necessarily the zero tangle.
Sports and Shows: Spectators in Contemporary Culture
Authors: Kennedy Dennis
Published: July 2002

The spectatorial relationship between sporting events and theatrical performance, based on recent sociological studies, reveals much about the nature of any audience position, and raises issues of class, economic status, and gender. Despite the heavy commodification and internationalization of professional sport, fans retain a remarkable sense of psychological investment in home teams, centred around notions of civic pride and communal ownership. They ardently follow the fortunes of their sides in a manner rarely associated with any other form of entertainment, a devotion that can lead to notable violence. Sporting events also constitute one of the few remaining examples of live television broadcasts. Television extends the implications of the sports spectator enormously, and is the foundation of the globalization of sports, but it also affects live audiences through the mediatization of some events.
The Maritime Safety System, its Main Components and Elements
Authors: Kopacz Z. , Morgaś W. , Urbański J.
Published: July 2002

The basic concepts safety at sea and the maritime safety system have remained almost
unchanged for a comparatively long time. However, the components and elements of these
concepts are now subject to many changes created by the ‘information age’. This paper
presents thoughts on today's concept of the maritime safety system, its main components and
their elements. Although the thoughts and ideas presented are those of the authors, they take
account of the legal instruments in force and recent developments in technology, especially
developments in radio-communications. The paper provides an overall review of the
institutions, regulations and procedures concerned with safety at sea.
GNSS & WGS 84 for Marine
Navigation in UK Waters
Authors: Ashkenazi Vidal , Moore Terry , Dumville Mark , Chen Wu , McPherson David , Millen Keith , Greenland Adam , Ward Nick , Savill Mike , Ruttle Stuart
Published: July 2002

The following paper reports on the progress of a large collaborative project in the UK to
investigate novel strategies for the implementation of GNSS within all phases of marine
navigation. The project is funded by the UK Government (Engineering and Physical
Sciences Research Council) under the leadership of the IESSG at the University of
Nottingham. The project receives the support from a prestigious team of collaborators which
include the UK Ministry of Defence Hydrographic Office, Trinity House Lighthouse Service,
Northern Lighthouse Board, Commissioners for Irish Lights and the Port of London
Authority. This consortium is of strategic importance, as their operations encompass the
provision of aids to navigation for all phases of marine transport within the UK and
elsewhere.
Testing the Quality of Information
on Tracked Vessels in a VTS Centre
with GNSS
Authors: Wawruch Ryszard , Cydejko Jarosław , Dziewicki Marek
Published: July 2002

This paper describes selective tests performed in the areas of Gdansk and Gdynia VTS
Centres. The main goal of the tests was to determine the accuracy of position, speed and
course estimations measured by shore-based radar VTS tracking systems by using
measurements of the same parameters available on board a tracked vessel equipped with
GPS and GLONASS receivers. Six DGPS/GPS/GLONASS receivers were installed on
board a survey vessel, and all of them recorded the vessel's route simultaneously with two
different VTS radars – one at Gdansk and one at Gdynia (20 km apart). All DGPS receivers
tracked the same reference station. Presented results show that the radar information can be
used by VTS operators to provide navigation assistance within certain limits, but these limits
must be understood. A more detailed description of the experiment was presented during the
IALA Conference in Hamburg in June 1998.
Forced migration, environmental change and woodfuel issues in the Senegal River Valley
Authors: BLACK RICHARD , SESSAY MOHAMED F.
Published: July 2002

There is increasing international concern about the environmental impacts of refugees on host areas, with governments calling for compensation for environmental damage, particularly concerning the loss of woodland resources as a result of demand for wood for fuel. In addition to an obvious increase in the population of host areas, concern about refugees' woodfuel-use centres on the notion that they are 'exceptional resource degraders'. Since they view their stay as temporary, it is argued, they therefore do not have any incentive to use resources in a way that is sustainable in the long term. This study examined refugee migration to the middle valley of the Senegal River, and compared woodfuel use by refugee and local populations. Drawing on a household survey and direct measurement of woodfuel use, little or no evidence is found to support the expectation that refugees use more wood for fuel than local people, or that they are more destructive in their collection or use of wood. This is important since it suggests that policy measures developed to reduce what is perceived as excess demand by refugees, notably through the introduction of fuel-efficient stoves, are unlikely to be successful. Reforestation schemes have been relatively unsuccessful in addressing supply or demand for wood.
Topological representation and reasoning in space
Authors: EL-GERESY BAHER A. , ABDELMOTY ALIA I.
Published: July 2002

In this article, an approach is presented for the
representation and reasoning over qualitative spatial relations.
A set-theoretic approach is used for representing the topology
of objects and underlying space by retaining connectivity
relationships between objects and space components in a
structure, denoted, adjacency matrix. Spatial relations
are represented by the intersection of components, and
spatial reasoning is achieved by the application of general
rules for the propagation of the intersection constraints
between those components. The representation approach is
general and can be adapted for different space resolutions
and granularities of relations. The reasoning mechanism
is simple and the spatial compositions are achieved in
a finite definite number of steps, controlled by the complexity
needed in the representation of objects and the granularity
of the spatial relations required. The application of the
method is presented over geometric structures that takes
into account qualitative surface height information. It
is also shown how directional relationships can be used
in a hybrid approach for richer composition scenarios.
The main advantage of this work is that it offers a unified
platform for handling different relations in the qualitative
space, which is a step toward developing general spatial
reasoning engines for large spatial databases.
Proof planning for maintainable configuration systems
Authors: LOWE HELEN , PECHOUCEK MICHAL , BUNDY ALAN
Published: July 2002

Configuration is a complex task generally involving
varying measures of constraint satisfaction, optimization,
and the management of soft constraints. Although many successful
systems have been developed, these are often difficult
to maintain and to generalize in rapidly changing domains.
In this paper, we consider building intelligent knowledge-based
systems with maintainability well to the fore in our requirements
for such systems. We introduce two case studies: the initial
proof of concept, which was in the domain of computer configuration,
and a further field-tested study, the configuration of
compressors. Central to our approach is the use of the
proof planning technique, and the clean separation of different
kinds of knowledge: factual, heuristic, and strategic.
Modelling rubella in Europe
Authors: EDMUNDS W. J. , VAN DE HEIJDEN O. G. , EEROLA M. , GAY N. J.
Published: July 2002

The prevention of congenital rubella syndrome (CRS), as a complication of rubella infection
during pregnancy, is the main aim of rubella vaccination programmes. However, as vaccination
of infants leads to an increase in the average age at which those who were not immunized
become infected, certain rubella vaccination programmes can lead to an increase in the
incidence of CRS. In this paper we use a mathematical model of the transmission dynamics of
rubella virus to investigate the likely impact of different vaccination policies in Europe. The
model was able to capture pre-and post-vaccination patterns of infection and prevalence of
serological markers under a wide variety of scenarios, suggesting that the model structure and
parameter estimates were appropriate. Analytical and numerical results suggest that endemic
circulation of rubella is unlikely in Finland, the United Kingdom, The Netherlands, and
perhaps Denmark, provided vaccine coverage is uniform across geographical and social groups.
In Italy and Germany vaccine coverage in infancy has not been sufficient to interrupt rubella
transmission, and continued epidemics of CRS seem probable. It seems unlikely that the
immunization programmes in these countries are doing more harm than good, but this may be
partly as a result of selective immunization of schoolgirls. Indeed, in both these countries,
selective vaccination of schoolgirls with inadequate vaccination histories is likely to be an
important mechanism by which CRS incidence is suppressed (unlike the other countries, which
have had sufficiently high infant coverage rates to withdraw this option). Reducing inequalities
in the uptake of rubella vaccine may bring greater health benefits than increasing the mean
level of coverage.
A longitudinal study of Escherichia coli O157 in fourteen

cattle herds
Authors: HANCOCK D. D. , BESSER T. E. , RICE D. H. , HERRIOTT D. E. , TARR P. I.
Published: July 2002

Escherichia coli O157 shedding in 14 cattle herds was
determined by

faecal culture at intervals

of approximately 1 month for up to 13 months. The overall prevalence was

1·0% (113/10832

faecal samples) and 9 of the 14 herds were detected as positive. Herds
positive

2 years

previously (n=5) had a higher prevalence of positive cattle

(median=1·9%) than herds which

had been negative on a previous sampling (n=8, median=0·2%).

Weaned heifers had a

higher prevalence (1·8%) than did unweaned calves (0·9%)
or adults

(0·4%). For all herds the

highest prevalence occurred in the summer months, which resulted in most
of

the positive faecal samples being collected on a minority of sampling

visits.
The prevalence of Serpulina pilosicoli in humans and domestic

animals in the Eastern Highlands of Papua New Guinea
Authors: TROTT D. J. , COMBS B. G. , MIKOSZA A. S. J. , OXBERRY S. L. , ROBERTSON I. D. , PASSEY M. , TAIME J. , SEHUKO R. , ALPERS M. P. , HAMPSON D. J.
Published: July 2002

In a survey of five villages in the Eastern Highlands of Papua

New Guinea, Serpulina pilosicoli

was isolated from rectal swabs from 113 of 496 individuals (22·8%).

Colonization rates ranged

from 22·6–30·1% in four of the villages but was only

8·6% in the other village. In comparison

colonization was demonstrated in only 5 of 54 indigenous people

(9·3%) and none of 76 non-indigenous people living in an urban environment

in the same region. Colonization did not

relate to reported occurrence of diarrhoea, age, sex, or length of time

resident in a village. A

second set of 94 faecal specimens was collected from 1 village 6 weeks
after

the first set. S.

pilosicoli was isolated from 27 of 29 individuals (93·1%) who

were positive on the first

sampling and from 7 of 65 individuals (10·8%) who previously were

negative. In this case,

isolates were significantly more common in watery stools than in normal

stools. The annual

incidence of infection in the village was calculated as 93·6%, with

an average duration of

infection of 117 days. S. pilosicoli could not be isolated

from any village pig (n=126) despite

its confirmed presence in 17 of 50 commercial pigs (34·0%) sampled
at a

local piggery. Four of

76 village dogs (5·3%) and 1 of 2 village ducks were colonized with

S. pilosicoli, suggesting the

possibility of cross transmission between humans and animals.
Pseudomonas aeruginosa as a cause of infectious diarrhoea
Authors: ADLARD P. A. , KIROV S. M. , SANDERSON K. , COX G. E.
Published: July 2002

Pseudomonas aeruginosa is not generally considered
a cause of infectious diarrhoea. However, it
was the predominant organism isolated from the faeces of 23 unrelated,
hospital outpatients
investigated in the course of a year for persistent (>1 week duration)

diarrhoea. To investigate
the possible aetiological role of P. aeruginosa, these
patient histories were reviewed and a selection of their faecal isolates

were investigated in vitro (n[ges ]10) and
in vivo (n=2) for
virulence. The patients had a mean age of 60 years, were receiving
antibiotics and/or had an
underlying illness. Extensive microbiological investigations identified
no other potential or
recognized enteropathogen in the faeces of 20 of these patients. More than
40% of the isolates
tested were able to adhere to HEp-2 cells and exhibited twitching motility
(type IV pili),
properties indicative of their ability to colonize the human intestine.
Cytotoxic activity was
demonstrated in bacterium-free cell supernatants of over 80% of isolates;
supernatants of four
isolates tested in infant mice were weakly enterotoxigenic. Two isolates
intragastrically
inoculated into clindamycin pre-treated rats established persistent infections
and induced signs
and symptoms of enteritis. Overall these findings suggest that P. aeruginosa
can cause
diarrhoea particularly in immunodeficient individuals.
Experimental infection of ostriches with Crimean–Congo
haemorrhagic fever virus
Authors: SWANEPOEL R. , LEMAN P. A. , BURT F. J. , JARDINE J. , VERWOERD D. J. , CAPUA I. , BRÜCKNER G. K. , BURGER W. P.
Published: July 2002

Following the occurrence of an outbreak of Crimean–Congo
haemorrhagic fever (CCHF)
among workers at an ostrich abattoir in South Africa in 1996, 9 susceptible
young ostriches
were infected subcutaneously with the virus in order to study the nature
of the infection which
they undergo. The ostriches developed viraemia which was
demonstrable on days 1–4 following
infection, with a maximum intensity of 4·0 log10 mouse
intracerebral
LD50/ml being recorded
on day 2 in 1 of the birds. Virus was detectable in visceral organs such
as spleen, liver and
kidney up to day 5 post-inoculation, 1 day after it could no longer be
found in blood. No
infective virus was detected in samples of muscle, but viral
nucleic acid was detected by reverse
transcription-polymerase chain reaction in muscle from a bird sacrificed
on day 3 following
infection. It was concluded that the occurrence of infection in ostriches
at abattoirs could be
prevented by keeping the birds free of ticks for 14 days before slaughter.
Reduction of campylobacter infections in broiler flocks by
application of hygiene measures
Authors: VAN DE GIESSEN A. W. , TILBURG J. J. H. C. , RITMEESTER W. S. , VAN DER PLAS J.
Published: July 2002

Transmission routes of Campylobacter spp. in broilers

and possibilities for prevention of
infections were studied on two Dutch broiler farms. The occurrence
of Campylobacter spp. was
studied in successive broiler flocks, in the environment of the farms and
in some of the parent
flocks involved. Isolates of Campylobacter spp. were typed by
using randomly amplified
polymorphic DNA (RAPD) analysis. The results indicate that broiler flocks
become infected
from environmental sources. The typing results suggest that on one farm
transmission of
Campylobacter spp. occurred from cattle to broilers via the farmer's

footwear. After several
campylobacter positive broiler cycles hygiene measures, including thorough
cleaning and
disinfection procedures, change of footwear at the entrance of each broiler
house, control of
vermin and other hygienic precautions, were introduced on both farms in
order to prevent
transmission of Campylobacter spp. from the farm environment to
the broilers. The results
indicate that the application of hygiene measures significantly reduced
campylobacter infections
of broiler flocks on both farms.
Bordetella pertussis surveillance in England and Wales: 1995–7
Authors: VAN BUYNDER P. G. , OWEN D. , VURDIEN J. E. , ANDREWS N. J. , MATTHEWS R. C. , MILLER E.
Published: July 2002

Available data sources on disease due to Bordetella pertussis, including notifications, hospital
admissions, deaths, and an enhanced laboratory-based surveillance system commenced in
January 1994, were reviewed for the period 1995–7. Pertussis notifications continued their
approximately 3-year cycle although at historically reduced levels. A slight seasonal increase in
late summer/early autumn existed over and above a relatively constant background rate. Over
time, the proportion of pertussis cases in younger, unvaccinated children, and to a lesser
extent, adolescents and young adults, is increasing. There is a continuing significant and under-
reported mortality associated with pertussis in the very young age group. Disease due to
serotype 1,2 is on the increase despite persistent high vaccination levels and this serotype
causes more severe disease. The provision of preventative antibiotics prior to disease onset
reduced the severity of the disease but its use remains uncommon in England and Wales. While
overall levels of pertussis notifications have declined in recent times, vaccination efficacy wanes
with increasing age, and pertussis remains a significant cause of mortality and severe morbidity
in the very young. This could be reduced by timely booster vaccination and increased
recognition of mild disease in older cases followed by early antibiotic therapy for the very
young household contacts.
Field evidence that roe deer (Capreolus capreolus) are a
natural host for Ehrlichia phagocytophila
Authors: ALBERDI M. P. , WALKER A. R. , URQUHART K. A.
Published: July 2002

Samples of blood, spleen and legs from 112 culled roe deer (Capreolus capreolus) were collected
from nine sites widespread in the United Kingdom. The prevalence of infection with Ehrlichia
phagocytophila was determined by serology and polymerase chain reaction. Means of 58% of
102 plasma or serum samples were seroreactive by IFA, 38% of 84 blood samples and 29% of
82 spleen samples were positive by PCR. Ticks on legs of 71 roe deer were Ixodes ricinus
larvae, nymphs and adults and 83% of legs were infested. Numbers of ticks corresponded
positively to the percentage of samples positive for E. phagocytophila by serology and PCR for
different sampling sites. Ixodes ricinus nymphs collected from the vegetation at one site with
infected deer were analysed for infection with E. phagocytophila by examination of Feulgen
stained salivary glands. Of 135 nymphs 5% were infected. These results confirm that roe deer
are commonly parasitized by both E. phagocytophila and its vector tick in such a way that it is
likely to be an important natural mammalian reservoir of E. phagocytophila.
Use of ELISAs in field studies of rabbit haemorrhagic disease (RHD) in Australia
Authors: COOKE B. D. , ROBINSON A. J. , MERCHANT J. C. , NARDIN A. , CAPUCCI L.
Published: July 2002

ELISA techniques developed for the veterinary diagnosis of Rabbit Haemorrhagic Disease
(RHD) in domestic rabbits were used for studying the epidemiology of RHD in Australian
wild rabbits. The combination of ELISA techniques that distinguished IgA, IgG and IgM
antibody responses and a longitudinal data set, mainly based on capture-mark-recapture of
rabbits, provided a reliable basis for interpreting serology and set the criteria used to classify
rabbits' immunological status. Importantly, young with maternal antibodies, immune rabbits
and rabbits apparently re-exposed to RHD were readily separated. Three outbreaks of RHD
occurred in 1996–7. The timing of RHD outbreaks was mainly driven by recruitment of young
rabbits that generally contracted RHD after they lost their maternally derived immunity.
Young that lost maternal antibodies in summer were not immediately infected, apparently
because transmission of RHDV slows at that time, but contracted RHD in the autumn when
conditions were again suitable for disease spread.
Vertebral osteology and swimming style in living and fossil whales (Order: Cetacea)
Authors: Buchholtz Emily A.
Published: July 2002

Morphological modification of the cetacean vertebral column for axial locomotion was one of many changes that occurred during and after the invasion of aquatic habitats by the ancestors of living whales. These modifications resulted in a column that can be divided into neck, chest, torso, and fluke structural and functional units. Variations in these units allow subdivision of living whales into three morphological groups that reflect differences in regional flexibility of the column and of locomotor style. Both odontocete and mysticete cetaceans exhibit trends toward reduction of relative centrum length in the neck and torso, restricting the flexibility of the column with increasing adaptation to aquatic lifestyles. Mysticetes and physeterid odontocetes retain the archaeocete pattern of constant vertebral shape along the torso, which acts as an undulatory unit. The location of secondary sites of reduced centrum length in non‐physeterid odontocetes subdivides them into subgroups, one with reduced posterior, and the other with reduced anterior, torso flexibility. The relationships between particular osteological patterns and swimming styles in living taxa are used to support predictions of swimming style in fossil species after adoption of a fluke in the late Eocene.
Effects of change in environmental temperature and natural shifts in carbon dioxide and oxygen concentrations on the lungs of captive naked mole‐rats (Heterocephalus glaber): a morphological and morphometric study
Authors: Maina J. N. , Gebreegziabher Y. , Woodley R. , Buffenstein R.
Published: July 2002

The lungs of the naked mole‐rat Heterocephalus glaber were morphologically (qualitatively) and morphometrically (quantitatively) investigated in adult captive in‐burrow body‐temperature‐maintained (CBTMA) and captive cold‐exposed animals (CCEA). The observations were compared with those of field (burrow‐dwelling) animals (FA) examined in an earlier study. The lungs of the captive animals were morphologically (qualitatively) similar to those of the field mole‐rats. Conspicuous paedomorphic features, i.e. a preponderant double pulmonary capillary arrangement, incomplete differentiation of alveolar pneumocytes, and extension of a cuboidal epithelium to the immediate vicinity of the alveoli, were observed. The prevalent pulmonary underdevelopment was attributed to the relatively low metabolic rate of the poikilothermic naked mole‐rat, a species that has evolved in a thermally stable environment. Measurable differences and similarities were found between the lungs of the captive naked mole‐rats themselves (i.e. the CBTMA and the CCEA) and between the captive and the field ones. Genetic factors may help explain the conserved pulmonary structural features while environmental (gaseous) change from a hypoxic–hypercapneic (an oxygen deficient–high carbon dioxide concentration) to a normoxic–normocapnic atmosphere and the thermal shift respectively may have enforced pulmonary transformations between the CBTMA and the FA and between the CCEA and the CBTMA. Paradoxically, the CCEA had a significantly lower mass‐specific total morphometric pulmonary diffusing capacity of 0.024 compared with that of 0.102 mlO2.s−1.mbar−1.kg−1 in the CBTMA. The observed morphometric differences indicate that the lung of the naked mole‐rat, though morphologically unchanged, is intrinsically tractable to environmental shifts in its habitat. Studies on captive naked mole‐rats should not be indiscriminately taken to be representative of the species.
Morphology and flight manoeuvrability in New World leaf‐nosed bats (Chiroptera: Phyllostomidae)
Authors: Stockwell Elizabeth F.
Published: July 2002

The relationship between wing morphology and ability to manoeuvre through an obstacle course was examined in five species of bats in the Neotropical family Phyllostomidae. These species represent a range of morphologies and feeding adaptations: Tonatia silvicola, a surface‐gleaning insectivore; Artibeus jamaicensis and A. literatus, canopy frugivores; and Carollia perspicillata and C. castanea, understory frugivores. Bats of known morphology were presented with three different obstacle arrangements chosen in random order. In order to control for wing span, spacing between obstacles was scaled to the wing span of the individual (1×, 0.75×, 0.5× the wing span of the bat). Performance was measured as the number of times a bat hit an obstacle hard enough to deflect it. Morphological variables were analysed using principal components analysis and were summarized by the first two principal components (PC): PC 1, ‘size’, with which size‐related variables were strongly, positively correlated; PC 2, ‘camber’, on which variables associated with maximum depth of wing camber weighted most heavily. Obstacle course performance was significantly correlated with both size and camber at all obstacle spacings: larger bats hit more obstacles, even though obstacle spacing was scaled to wing span, and bats with better ability to camber wings hit fewer obstacles. These results show that bat species that forage in more cluttered habitats are more likely to be small in size and/or have wings able to produce the high camber necessary to maintain lift at low flight speeds.
The demography of an African elephant (Loxodonta africana) population in Amboseli, Kenya
Authors: Moss Cynthia J.
Published: July 2002

This paper presents basic demographic parameters of African elephants (Loxodonta africana) living in and around Amboseli National Park, Kenya. The study was conducted from 1972 to the present and results are based on the histories of 1778 individually known elephants. From 1972 to 1978, the Amboseli elephant population declined and then increased steadily from 1979 to the present. Births occurred throughout the year but over 80% occurred between November and May. Birth rate varied from year to year with a pattern of peaks and troughs at 4‐ to 5‐year intervals. The birth sex ratio did not differ significantly from 1:1. Mean age at first birth was 14.1 years, determined from a sample of 546 known‐age females. Mean birth interval (n= 732) was 4.5 years for 255 females. Fecundity and calf survival varied by age of the females. Mortality fluctuated from year to year. Sex‐specific mortality rates were consistently higher for males than females at all ages.
Cranial morphology of the anguilliform clariid Channallabes apus (Günther, 1873) (Teleostei: Siluriformes): are adaptations related to powerful biting?
Authors: Devaere Stijn , Adriaens Dominique , Verraes Walter , Teugels Guy T.
Published: July 2002

Within the clariids (air‐breathing catfish), a complete range of fusiform to anguilliform species can be observed. This study deals with the cranial morphology of Channallabes apus, an extreme anguilliform (eel‐like) species, compared to the anguilliform Gymnallabes typus and the more fusiform Clarias gariepinus. The overall morphology of the head of Channallabes apus shows a hypertrophied adductor mandibulae complex, with the corresponding substantial narrowing of the neurocranium, seen in the frontals, the sphenotics, the pterotics and the posttemporo‐supracleithra, as well as the reduction and displacement of the eyes and some canal bones, such as the infraorbitals and the suprapreopercles. The presence of a hypertrophied muscle complex possibly indicates that a more powerful bite may occur. This implies that adaptations can be expected in several parts of the skull. On the lower jaw of C. apus a higher coronoid process is found, and on the suspensorium, two sets of three processes are present on the hyomandibular bone, indicating a stronger connection to the neurocranium. Several of the observed features, such as the elongation of the body, the reduction of the eyes, the increase in vertebrae number, limblessness and the increasing rigidity of the skull, may also be related to a process of miniaturization.
Female dispersal and relatedness structure in common wombats (Vombatus ursinus)
Authors: Banks Sam C. , Skerratt Lee F. , Taylor Andrea C.
Published: July 2002

Dispersal patterns were investigated in the common wombat Vombatus ursinus using microsatellite genetic data collected from three study sites. Two of these were within large, high‐density populations in Victoria, south‐eastern Australia, while the third was a small, isolated population in South Australia. Genetic assignment tests revealed that in the continuous populations, females were more likely to be immigrants into the sampling areas than were males, who were more likely to have been born locally. No such difference between the sexes was detected for the isolated population. At all three sites, pairwise relatedness estimates for males were negatively correlated with geographic distance, suggesting related males were clustered. This pattern was not observed among females, other than in the isolated population, where pairs of females showed a weak decline of relatedness with increasing geographic distance over a large spatial scale. Taken together, these data provide strong evidence that dispersal is predominantly by females. Furthermore, the observed spatial structure of relatedness suggests female breeding dispersal, a rare finding among mammalian species. Genetic variation within the isolated population was significantly reduced compared to the sites in Victoria. Our data are not sufficient to distinguish between two possible causes for this: (1) long‐term small size and isolation of populations at the edge of the species' range where resources may be more patchily distributed; (2) a genetic bottleneck effect of recent isolation resulting from agricultural development.
Striving to do well what comes naturally: Social support, developmental psychopathology,

and social policy
Authors: THOMPSON ROSS A. , ONTAI LENNA
Published: July 2002

Social support can have significant stress-preventive and stress-buffering benefits for troubled

individuals in everyday circumstances. Consequently, it is not surprising that many therapeutic and

preventive programs enlist social support to address problems of child and family

psychopathology, especially in the context of “two-generation interventions” that

seek to improve child well-being by strengthening parental functioning and parent–child

relationships. Home visitation programs are the best known of these two-generation strategies and

have become the focus of state-level and national efforts to support families and prevent harm to

children. The conclusions of basic research studies on social support converge significantly with

the findings of evaluation studies of the impact of home visitation programs to yield important

new insights into the conditions in which formal social support is likely to be beneficial, or

ineffective, in improving child and family well-being. Both basic and applied research literatures

emphasize the importance of linking formal social support to informal social networks in extended

families, neighborhoods, and communities, and attending to the complex reactions of the

recipients of support and the needs of support providers. These studies are reviewed and

evaluated to highlight the connections between social support, developmental psychopathology,

and social policy.
Drug abuse and developmental psychopathology
Authors: GLANTZ MEYER D. , LESHNER ALAN I.
Published: July 2002

Drug abuse research and theory has become much more sophisticated over the last 2 decades,

and some of the advancements parallel concepts that are part of the developmental

psychopathology approach. The application of the developmental psychopathology perspective to

recent drug abuse research findings can provide a greater understanding of that information and

point to important areas of future research. Among the drug abuse research areas discussed here

and viewed from this perspective are antecedent and co-occurring psychopathological conditions

and other problem behaviors; the diversity of the nature of, paths to, and processes and outcomes

related to drug abuse; the role of intermediary influences; the interaction of individual and

environmental predisposing and protective factors; the role of families and other social institutions

in intervention; and developmental stage characteristics. Directions for future research are also

discussed.
Parent participation in community activities and the persistence of criminality
Authors: MAHONEY JOSEPH L. , MAGNUSSON DAVID
Published: July 2002

This study assessed whether the lack of parental participation in community activities during
late childhood is significantly related to the persistence of criminal activity from adolescence to
adulthood. A prospective, longitudinal investigation of a representative cohort of 548 boys from a
middle-sized Swedish community was employed. A pattern-oriented analysis identified five
configurations of boys who showed different profiles of social and academic competence at the
age of 13 years. The configurations were compared with respect to persistent criminality among
the boys for parents who did, and who did not, show stable participation in a community activity
when their sons were in late childhood. Fathers engaged in a community activity had sons with
significantly lower rates of persistent criminality. This result was most marked for youth with low
school achievement, and multiple problem profiles of social and academic disadvantage. The
findings held after controlling for family socioeconomic status. Mother's participation in
community activities was statistically dependent on father participation but was not related to
persistent offending among multiple problem boys. Results are discussed in terms of the different
impact associated with mother and father community activity participation on persistent offending,
and the holistic perspective to development guiding this research.
Early organization of the nonlinear right brain and development of a predisposition to

psychiatric disorders
Authors: SCHORE ALLAN N.
Published: July 2002

The concepts of self-organization, state changes, and energy flow are central to dynamic

systems theory. In this work I suggest that to apply these general principles to the study of normal

and abnormal development, these constructs must be specifically defined in reference to current

knowledge of brain development. Toward that end, I present an overview of the properties of

self-organizing developmental systems, and then propose a model of attachment dynamics as

synchronized energy exchanges that cocreate nonlinear changes of state, discuss the roles of

bioamines and energy-generating brain mitochondria in state regulation, and describe the

energy-dependent imprinting of synaptic connectivity and neural circuitry in the infant brain. In

this application of nonlinear concepts to developmental models of both resistance against and

vulnerability to mental disorders, particular emphasis is placed upon the experience-dependent

maturation of a system in the orbital prefrontal cortex that regulates psychobiological state and

organismic energy balance. This frontolimbic system is expanded in the nonlinear right

hemisphere that generates stress-regulating coping strategies, and it serves as the hierarchical

apex of the limbic and autonomic nervous systems. Early forming microstructural alterations and

energetic limitations of this regulatory system are suggested to be associated with a

predisposition to psychiatric disorders.
Mothering, fathering,
and infant negativity as antecedents of boys' externalizing problems and inhibition at age 3
years: Differential susceptibility to rearing experience?
Authors: BELSKY JAY , HSIEH KUANG-HUA , CRNIC KEITH
Published: July 2002

To examine the effects of infant negative
emotionality and of mothering and fathering during the toddler years on 3-year-old boys'
externalizing problems and inhibition, as well as explore the proposition that children vary in
their susceptibility to rearing influence, 125 first-born, Caucasian boys from maritally intact
families were studied. Results revealed that when infant negativity is measured with objective,
replicable, and discriminantly valid procedures, no relation obtains between it and externalizing
problems (nor inhibition). Moreover, as hypothesized on the basis of prior work, parenting was a
stronger predictor of externalizing problems and inhibition in the case of children who were
highly negative as infants. Mothering proved a stronger predictor of externalizing problems and
fathering of inhibition, with more negative mothering in the 2nd and 3rd year forecasting higher
CBCL-externalizing scores and less negative fathering in the 2nd and 3rd year and more positive
fathering in the 2nd year forecasting more inhibition at age 3. Implications of these findings for
studies of parental influence are considered.
Neuroendocrine activity and memory-related impairments in
posttraumatic stress disorder
Authors: GOLIER JULIA , YEHUDA RACHEL
Published: July 2002

This article
reviews memory-related impairments in trauma survivors with posttraumatic stress disorder and
their possible association to neuroendocrine alterations seen in this disorder. The neuroendocrine
profile in PTSD first described in chronically ill combat veterans is characterized by lower basal
cortisol levels, higher glucocorticoid receptor number, enhanced sensitivity to exogenous
steroids, and increased variation in basal cortisol levels over the diurnal cycle. The
generalizability and time course of these neuroendocrine alterations are explored in longitudinal
studies and studies in other traumatized populations. These studies suggest that at least some
aspects of this neuroendocrine profile can also be seen in other populations, including women,
children, and victims of childhood trauma. Additionally, the alterations may be present early in
the course of illness, perhaps even in the immediate aftermath of trauma, and may continue to be
manifest in elderly trauma survivors. The mechanisms by which these neuroendocrine alterations
may influence the formation and processing of traumatic memories are discussed.
A prospective cohort study of neurodevelopmental processes in the
genesis and epigenesis of schizophrenia
Authors: CANNON TYRONE D. , ROSSO ISABELLE M. , BEARDEN CARRIE E. , SANCHEZ LAURA E. , HADLEY TREVOR
Published: July 2002

A number of lines of evidence converge in implicating neurodevelopmental processes in the
etiology and epigenesis of schizophrenia. In this study we used a prospective, longitudinal design
to examine whether adverse obstetric experiences predict schizophrenia and whether there is a
deviant functional–developmental trajectory during the first 7 years of life among
individuals who manifest schizophrenia as adults. The 9,236 members of the Philadelphia cohort
of the National Collaborative Perinatal Project were screened for mental health service utilization
in adulthood, and chart reviews were performed to establish diagnoses according to DSM-IV
criteria. The risk for schizophrenia increased linearly with the number of hypoxia-associated
obstetric complications but was unrelated to maternal infection during pregnancy or fetal growth
retardation. Preschizophrenic cases (and their unaffected siblings who were also cohort
members) manifested cognitive impairment, abnormal involuntary movements and coordination
deficits, and poor social adjustment during childhood. There was no evidence of intraindividual
decline in any domain, but preschizophrenic cases did show deviance on an increasing number of
functional indicators with age. Together, these findings suggest that both genetic and obstetric
factors participate in creating a neural diathesis to schizophrenia, the phenotypic expressions of
which are age dependent, probably reflecting the maturational status of a number of
interconnected brain systems.
Cognitive and behavioral precursors of schizophrenia
Authors: CORNBLATT BARBARA , OBUCHOWSKI MICHAEL , ROBERTS SIMONE , POLLACK SIMCHA , ERLENMEYER–KIMLING L.
Published: July 2002

Attentional deficits are well-established characteristics of patients with schizophrenia and
their at-risk offspring, suggesting a biological connection between attention and schizophrenia.
The goal of this study is to clarify the developmental role of attention in the illness. Data has
been collected from 87 subjects at high and low risk for schizophrenia who have participated in
the New York High-Risk Project from 1977 to the present. Individuals are considered to be at
high risk if either or both of their parents has schizophrenia. Analyses of attention and global
behaviors, measured at intervals from about 12 to 26 years of age, indicate (a) attentional deficits
can be reliably detected in high-risk children who will develop future schizophrenia-spectrum
disorders (the prespectrum [PSP] group); (b) these deficits are stable, enduring over time, and
appear to reflect a compromised attentional capacity; (c) attention is not affected by the onset of
illness in the PSP group; (d) for all subjects, attention and global behaviors follow independent
developmental pathways; and (e) behavioral difficulties, but not attention deficits, appear to be
highly sensitive to environmental factors, especially rearing by a mentally ill parent. It is
concluded that in PSP individuals impaired attention probably results from prenatal
developmental abnormalities (possibly on the cellular level) and is likely to be a marker of a
biological vulnerability to schizophrenia. In addition, attentional deficits, as opposed to early
behavioral difficulties, are concluded to be a useful first step in screening for youngsters in need
of early intervention.
Developmental neuropsychopathology of attention deficit and impulsiveness
Authors: TAYLOR ERIC
Published: July 2002

Recent research on the disorders of attention and activity has indicated inherited variants of
genes controlling aspects of neurotransmission, abnormalities of structure and function in regions
of frontal lobes and basal ganglia, failures to suppress inappropriate responses, and a cascade of
failures in various kinds of cognitive performance and organization of behavior. This review
integrates the neurodevelopmental findings with findings from developmental psychopathology.
It outlines several developmental tracks by which constitutional factors interact with the
psychological environment. In one set of tracks, altered brain states lead to cognitive alteration.
An understimulating environment is evoked by (and may be genetically associated with) an
inattentive and cognitively impulsive style during early childhood. In another track, impulsive
and inattentive behavior shows direct continuity through childhood into late adolescence. In yet
another track, impulsiveness evokes (and may be genetically associated with) critical expressed
emotion from parents and inefficient coping strategies, which in turn contribute to the
development of antisocial conduct. This formulation emphasizes the need for several types of
research: the mapping of biological findings onto different components of disorder, the
combination of genetically informative designs with direct measurement of relevant aspects of
the environment, and the use of longitudinal studies to examine predictive and mediating factors
separately for different aspects of outcome.