bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and photosynthesis of seedlings of four tree species from a dry tropical afromontane forest
Authors: FETENE MASRESHA , FELEKE YONAS
Published: July 2002

Growth, photosynthesis and carbon allocation pattern were studied in four dry afromontane forest tree
species (Olea europea subspecies cuspidata, Podocarpus falcatus, Hagenia abyssinica and Juniperus procera) under
varied light regimes in a greenhouse. The objective of the study was to assess the potential of the species for growth
under forest canopies and to identify their habitat preferences. The light regimes were created using shade cloth and
they corresponded with deep forest understoreys (2% of the light in the open gap); moderate shade (10%), slight shade
as is found in edges of forest gaps (20%) and 100% representing open gaps.

Seedling biomass was significantly influenced by light regimes for all species as were total leaf area and relative
growth rate. H. abyssinica had the highest growth rate but the lowest survival rate in shade. There was a consistent
trend for higher specific leaf area (SLA) and leaf area ratio (LAR) at lower growth light regimes in O. europea and P.
falcatus. O. europea and P. falcatus had similar allocation patterns whereby between 20-40% of the total biomass was
allocated to stem, 20-30% to roots and 50-60% to leaves. In H. abyssinica up to 80% was allocated to leaves and only
a small percentage to stem and to roots.

Within species there were significant differences in the light saturated rate of photosynthesis (Amax) per unit area
among the plants grown at the lowest light level and in the open. For plants grown in the open there were very little
among species differences in Amax per unit area. However, there were significant differences in the Amax of the
different species grown at the lowest light level. Chlorophyll fluorescence measurements indicated that open-grown P.
falcatus and O. europea experienced moderate photoinhibition. From the growth and photosynthesis results P. falcatus
and O. europea appeared to be non-pioneer, shade-tolerant species, while J. procera and to a larger extent H. abyssinica
showed pioneer, light-demanding characteristics. The results are discussed in terms of the occurrence of the species
in the mosaic climaxes of afromontane forests.
Learning in multi-agent systems
Authors: ALONSO EDUARDO , D'INVERNO MARK , KUDENKO DANIEL , LUCK MICHAEL , NOBLE JASON
Published: July 2002

In recent years, multi-agent systems (MASs) have received increasing attention in the artificial intelligence community. Research in multi-agent systems involves the investigation of autonomous, rational and flexible behaviour of entities such as software
programs or robots, and their interaction and coordination in such diverse areas as robotics (Kitano et al., 1997), information retrieval and management (Klusch, 1999), and simulation (Gilbert & Conte, 1995). When designing agent systems, it is impossible to foresee all the potential situations an agent may encounter and specify an agent behaviour optimally in advance. Agents therefore have to learn from, and adapt to, their environment, especially in a multi-agent setting.
Simplifying decision trees: A survey
Authors: BRESLOW LEONARD A. , AHA DAVID W.
Published: July 2002

Induced decision trees are an extensively-researched solution to classification tasks. For many practical tasks, the trees produced by tree-generation algorithms are not comprehensible to users due to their size and complexity. Although many tree induction
algorithms have been shown to produce simpler, more comprehensible trees (or data structures derived from trees) with good classification accuracy, tree simplification has usually been of secondary concern relative to accuracy, and no attempt has been made to survey the literature from the perspective of simplification. We present a framework
that organizes the approaches to tree simplification and summarize and critique the approaches within this framework. The purpose of this survey is to provide researchers and practitioners with a concise overview of tree-simplification approaches and insight into their relative capabilities. In our final discussion, we briefly describe some empirical findings and discuss the application of tree induction algorithms to case retrieval in case-based reasoning systems.
Knowledge representation for interactive multimedia systems
Authors: VOUROS G. A.
Published: July 2002

Intelligent multimedia systems (IMMS) assist users in choosing the information content, and to design the information presentation, that satisfies their needs and idiosyncrasies. Towards this target, IMMSs posses and utilize knowledge concerning the means and function (purpose) of a presentation. ‘Means’ denote communication techniques (information carriers and modalities), as well as information content and information characteristics. The ‘function of a pr
esentation’ denotes the communicative purpose of the presentation, methods for achieving that purpose, as well as a user's goals and tasks.
FORM-MEANING CONNECTIONS AND THE FRENCH CAUSATIVE
Authors: Allen Linda Quinn
Published: July 2002

This study examines the generalizability of VanPatten and Cadierno (1993b) by investigating
the relative effect of two types of explicit grammar instruction on learners' ability to
interpret and produce sentences containing the French causative. Nine classes of 179
fourth-semester French students were assigned to three groups: (a) processing instruction, (b)
traditional instruction, and (c) no instruction. The results indicate that processing instruction is as
effective as traditional instruction in enabling learners to interpret the French causative and that
traditional instruction is more effective in enabling learners to produce the French causative.
THE ACQUISITION OF THE IP SYSTEM IN CHILD L2 ENGLISH
Authors: Haznedar Belma
Published: July 2002

This study examines the acquisition of the inflectional system by a Turkish child learner of
English. Results from longitudinal data collected over 18 months are reported, presenting
counterevidence for recent hypotheses on early L2 acquisition according to which missing
functional items reflect missing functional categories (e.g., Vainikka & Young-Scholten,
1994, 1996a, 1996b). Despite robust evidence for the early production of copula be,
auxiliary be, and overt subjects, the child L2 data analyzed in this paper do not show
any evidence for tense and agreement morphology in the early stages of L2 development. In other
words, although some functional elements related to IP are missing, the learner is able to perform
other morphological and syntactic operations involving the functional projection IP. These
findings lead us to question whether the lack of functional elements entails the lack of functional
categories.
ASYMMETRY OF NULL SUBJECTS AND NULL OBJECTS IN CHINESE
SPEAKERS' L2 ENGLISH
Authors: Yuan Boping
Published: July 2002

One of the differences between Chinese and English is that the former allows both null
subjects in finite sentences and null objects, but the latter allows neither. This cross-linguistic
variation is believed to be related to the underspecification of I and topic drop in Chinese but not
in English. This paper reports on an empirical study investigating the unlearning of null subjects
and null objects by 159 Chinese learners in their L2 acquisition of English. In L1 acquisition, it
has been found that English-speaking children display an asymmetry by frequently allowing null
subjects but rarely null objects. The results of this study indicate that there is an asymmetry in
Chinese learners' L2 English, which, however, is opposite to that found in English L1
acquisition: Chinese learners are able to reject the incorrect null subject in English, but unable to
detect the ungrammaticality of the null object. It is proposed that the unlearning of null subjects
by Chinese learners of English is triggered by the evidence in their input indicating the
specification of AGR(eement) and T(ense) in English, and that the difficulty in the unlearning of
null objects is related to the lack of informative evidence to unset the [+ topic-drop]
setting in Chinese learners' L2 English.
THE ACQUISITION OF ONSETS IN A MARKEDNESS RELATIONSHIP
Authors: Carlisle Robert S.
Published: July 2002

This article reports the findings of a longitudinal study in interlanguage phonology
examining the production of two structures in a markedness relationship, biliteral and triliteral
onsets, the latter being more marked than the former. This study specifically tests the
Interlanguage Structure Conformity Hypothesis (ISCH) by measuring the acquisition of the
onsets in the markedness relationship against a criterion measure of 80% correct production. The
subjects were 10 native Spanish speakers enrolled in intermediate courses in a community
college. Data were gathered twice over a period of 10 months. Results of the study fail to provide
any counterevidence to the ISCH.
INPUT, INTERACTION, AND SECOND LANGUAGE DEVELOPMENT
Authors: Mackey Alison
Published: July 2002

This study examines the relationship between different types of conversational interaction
and SLA. Long's (1996) updated version of the interactionist hypothesis claims that
implicit negative feedback, which can be obtained through negotiated interaction, facilitates
SLA. Similar claims for the benefits of negotiation have been made by Pica (1994) and Gass
(1997). Some support for the interaction hypothesis has been provided by studies that have
explored the effects of interaction on production (Gass & Varonis, 1994), on lexical
acquisition (Ellis, Tanaka, & Yamazaki, 1994), on the short-term outcomes of pushed
output (see Swain, 1995), and for specific interactional features such as recasts (Long, Inagaki,
& Ortega, 1998; Mackey & Philp, 1998). However, other studies have not found
effects for interaction on grammatical development (Loschky, 1994). The central question
addressed by the current study was: Can conversational interaction facilitate second language
development? The study employed a pretest-posttest design. Adult ESL learners (N =
34) of varying L1 backgrounds were divided into four experimental groups and one control
group. They took part in task-based interaction. Research questions focused on the
developmental outcomes of taking part in various types of interaction. Active participation in
interaction and the developmental level of the learner were considered. Results of this study
support claims concerning a link between interaction and grammatical development and
highlight the importance of active participation in the interaction.
Age-related changes in preschool children's systematic use of private speech in a natural setting
Authors: WINSLER ADAM , CARLTON MARTHA P. , BARRY MARYANN J.
Published: July 2002

This study set out to explore the contexts in which preschool children

use private speech, or self-talk, in the naturalistic setting of the

preschool classroom, and age-related changes in the contexts in which

preschoolers talk to themselves. A total of 2752 naturalistic observations

of fourteen three-year-old and fourteen four-year-old children were

conducted using a time-sampling procedure in two preschool classrooms

over the course of one semester. Results from logistic regression analyses

revealed that both age groups were (a) more likely to use private speech

during the self-selected activity classroom context as opposed to both

large group and outside free play classroom contexts, and (b) most likely

to talk to themselves when alone, next likely in the presence of peers, and

least likely when in the presence of a teacher. Although the probability

of private speech among three-year-old children did not vary as a

function of the child's immediate activity, four-year-old children's

private speech was more likely to occur during sustained and focused

goal-directed activity as opposed to rapidly-changing and non goal-directed activity. The findings suggest that private speech appears

systematically in young children and that, in several ways, four-year-old

children use private speech more selectively than three-year-olds.
Bilingual signed and spoken language acquisition from birth: implications for the mechanisms underlying early bilingual language acquisition
Authors: PETITTO LAURA ANN , KATERELOS MARINA , LEVY BRONNA G. , GAUNA KRISTINE , TÉTREAULT KARINE , FERRARO VITTORIA
Published: July 2002

Divergent hypotheses exist concerning the types of knowledge underlying
early bilingualism, with some portraying a troubled course marred
by language delays and confusion, and others portraying one that is
largely unremarkable. We studied the extraordinary case of bilingual
acquisition across two modalities to examine these hypotheses. Three
children acquiring Langues des Signes Québécoise and French, and
three children acquiring French and English (ages at onset approximately
1;0, 2;6 and 3;6 per group) were videotaped regularly over one
year while we empirically manipulated novel and familiar speakers of
each child's two languages. The results revealed that both groups
achieved their early linguistic milestones in each of their languages at the
same time (and similarly to monolinguals), produced a substantial
number of semantically corresponding words in each of their two
languages from their very first words or signs (translation equivalents),
and demonstrated sensitivity to the interlocutor's language by altering
their language choices. Children did mix their languages to varying
degrees, and some persisted in using a language that was not the primary
language of the addressee, but the propensity to do both was directly
related to their parents' mixing rates, in combination with their own
developing language preference. The signing-speaking bilinguals did
exploit the modality possibilities, and they did simultaneously mix their
signs and speech, but in semantically principled and highly constrained
ways. It is concluded that the capacity to differentiate between two
languages is well in place prior to first words, and it is hypothesized that
this capacity may result from biological mechanisms that permit the
discovery of early phonological representations. Reasons why paradoxical
views of bilingual acquisition have persisted are also offered.
The acquisition of personal pronouns in French-speaking and

English-speaking children
Authors: GIROUARD PASCALE C. , RICARD MARCELLE , DÉCARIE THÉRÈSE GOUIN
Published: July 2002

This paper presents a longitudinal study on the acquisition of
first,

second, and third person pronouns in twelve French-speaking and

twelve English-speaking children. Comprehension and production data

were collected every two months, beginning when the subjects were

aged 1;6 and ending once pronouns were fully acquired. Three hypotheses

concerning the rules children develop in learning pronouns

were tested: (1) the person-role hypothesis (Charney, 1980), (2) the

speech-role hypothesis (Clark, 1978), and (3) the name hypothesis

(Clark, 1978). An analysis of children's pronominal confusion when
they

were addressed listeners as well as when they were non-addressed

listeners was performed. The results indicated that the mastery of

pronouns did not follow the developmental sequence predicted by the

speech-role hypothesis; they provided evidence for the person-role

hypothesis only when children were speakers, and partially supported

the name hypothesis. The data also suggested that pronominal confusion

is not a rare phenomenon among children tested in a non-addressee

context. Finally, effects of child gender and native language were

observed. Possible interpretations of the data are discussed.
Subject–verb agreement in Brazilian Portuguese: what low error
rates hide
Authors: RUBINO REJANE B. , PINE JULIAN M.
Published: July 2002

This study focuses on the acquisition of subject–verb agreement
in
Brazilian Portuguese. A quantitative analysis of the data produced by a

Brazilian child between the ages of 3;02.07 and 3;04.08 is presented.
The overall error rate is low. However, a further and more detailed
analysis reveals important contrasts both in the frequency of production

of different verb inflections (as regards the person/number variables

within the verb morphological system) and in the rate of subject–verb

agreement errors associated with them. Our findings not only suggest
that subject–verb agreement may be acquired piecemeal, but also that

the learning of particular verb inflections may itself be a gradual process.

Alternatives to the idea of rule-governed production – such as the

child's reproducing frozen subject–verb strings previously produced
by
adults and blending different frozen strings into novel combinations –

are discussed as processes which can shed some light on the pattern of

both erroneous and correct production shown by this child.
A comparison of the transition from first words to
grammar in English and Italian
Authors: CASELLI CRISTINA , CASADIO PAOLA , BATES ELIZABETH
Published: July 2002

Cross-linguistic similarities and differences in early lexical
and grammatical
development are reported for 1001 English-speaking children
and 386 Italian-speaking children between 1;6 and 2;6. Parents completed

the English or Italian versions of the MacArthur Communicative
Development Inventory: Words and Sentences, a parent report instrument

that provides information about vocabulary size, vocabulary
composition and grammatical complexity across this age range. The
onset and subsequent growth of nouns, predicates, function words and
social terms proved to be quite similar in both languages. No support
was found for the prediction that verbs would emerge earlier in Italian,

although Italians did produce a higher proportion of social terms, and

there were small but intriguing differences in the shape of the growth

curve for grammatical function words. A strikingly similar nonlinear
relationship between grammatical complexity and vocabulary size was
observed in both languages, and examination of the order in which
function words are acquired also yielded more similarities than differences.

However, a comparison of the longest sentences reported for a
subset of children demonstrates large cross-linguistic differences in the

amount of morphology that has been acquired in children matched for
vocabulary size. Discussion revolves around the interplay between
language-specific variations in the input to young children, and universal

cognitive and social constraints on language development.
Cohesion and anaphora in children's narratives:
a comparison of English, French, German, and
Mandarin Chinese
Authors: HICKMANN MAYA , HENDRIKS HENRIËTTE
Published: July 2002

The aim of this study is to determine universal vs. language-specific
aspects of children's ability to organize cohesive anaphoric relations in
discourse. Analyses examine narratives produced on the basis of two
picture sequences by subjects of four ages (preschoolers, seven-year-olds, ten-year-olds, adults) in four languages: English (n = 80), German
(n = 40), French (n = 40), and Mandarin Chinese (n = 40). Particular
attention is placed on the impact of syntactic, semantic, and pragmatic
factors in determining the uses of referring expressions and of word
order in the maintenance of reference to the animate characters.
Although subjecthood and agency determine NP position within the
clause, role relations in discourse coreference account for NP form in all
languages, notwithstanding some variations across languages, ages, and
referents (e.g. density of coreference, null elements vs. overt pronouns,
clause structures). It is concluded that the development of anaphora is
determined by universal pragmatic principles and by language-specific
properties characterizing how languages map discourse-internal and
sentence-internal functions onto the same forms.
Characteristic varieties of arrangements
Authors: COHEN DANIEL C. , SUCIU ALEXANDER I.
Published: July 2002

The kth Fitting ideal of the Alexander invariant
B of an arrangement [Ascr ] of n complex hyperplanes defines a
characteristic subvariety, Vk([Ascr ]), of the algebraic torus
([Copf ]*)n. In the combinatorially determined case
where B decomposes as a direct sum
of local Alexander invariants, we obtain a complete description of
Vk([Ascr ]). For any
arrangement [Ascr ], we show that the tangent cone at the identity of this variety coincides
with [Rscr ]1k(A), one of the cohomology
support loci of the Orlik–Solomon algebra.
Using work of Arapura [1], we conclude that all irreducible
components of Vk([Ascr ]) which pass through the identity
element of ([Copf ]*)n are combinatorially determined,
and that [Rscr ]1k(A) is the union of a subspace
arrangement in [Copf ]n, thereby resolving a
conjecture of Falk [11]. We use these results to study the
reflection arrangements associated to monomial groups.
‘Homescapes’ and Identity Reformations in Australian Multicultural Drama
Authors: Tompkins Joanne
Published: July 2002

A consideration of identity formation in contemporary Australian multicultural theatre is offered through a re-assessment of the unsettled (and unsettling) constructions of Australia as ‘home’ in the work of three playwrights. William Yang's Sadness disrupts a localized perception of home, space, and cultural communities to amalgamate two disparate communities (the queer/homosexual community in Sydney and the Asian-Australian, or ‘Austasian’ community) into a reconfigured Australian identity. Janis Balodis's The Ghosts Trilogy uses many actors who play across the unsettled lines of history, amid numerous voices, homes, and homelands that indicate the enormity of what ‘Australia’ comes to signify. Noëlle Janaczewska's The History of Water constructs a way of locating the self by means of a metaphoric home as each character establishes herself on a psychic plane rather than choosing the strictly physical locations to which she has access. In their interrogations of home and homeland, these plays challenge assumptions regarding identity, disrupt notions of the ultimate ownership of land/culture by anyone, and problematize the idea of settlement as it is currently articulated in Australia.
Effects of rainfall and grazing on vegetation yield and cover of two arid rangelands in Kuwait
Authors: ZAMAN SAMEEHA
Published: July 2002

Increasing human pressure has presumably led to a decrease in the cover and herbage yield of Kuwaiti desert vegetation, but, to date, there has been little detailed study on such human impacts. A study of Rhanterium epapposum (local name arfaj) and Haloxylon salicornicum (local name remeth) steppe was therefore effected to determine the seasonal variation in above-ground phytomass and percentage cover, and to investigate differences between protected and adjacent grazed areas.

An average seasonal precipitation of 90 mm supported a mean of 223 kg ha-1 in arfaj steppe in 1979–1989, whereas an average mean seasonal precipitation of 73 mm during 1983–1989 maintained a mean phytomass of 102 kg ha-1 in the remeth steppe. Annual forbs and perennial shrubs were the greatest producers of dry matter per kg of phytomass in the arfaj and remeth steppes, respectively. The seasonal production of dry matter was related directly to the seasonal precipitation in the arfaj steppe, whereas the remeth steppe did not show an obvious relationship to the precipitation. The plant cover was 83% and 70% less, and herbage production was 76% and 91% less in grazed areas than in protected areas in the arfaj and remeth steppes, respectively.
Local attitudes toward community-based conservation policy and programmes in Nepal: a case study in the Makalu-Barun Conservation Area
Authors: MEHTA JAI N. , KELLERT STEPHEN R.
Published: July 2002

Community-based conservation (CBC) has been projected as the most practical approach to stem biodiversity loss in developing countries. Since CBC is 'people-centred' and experience with it is relatively new, it is important to know the views of local communities regarding implemented policies and programmes. This paper examines the attitudes of local communities toward policy and programmes implemented by a project under the CBC approach in the Makalu-Barun National Park and Conservation Area of Nepal, based on a 1996 survey of 400 people living in it.

Overall, respondents did not have a particularly favourable perception of the community development programmes implemented. Strong support existed for ecotourism development in the Conservation Area. Respondents overwhelmingly endorsed community forestry. Wildlife protection remained a low priority amongst a significant majority of respondents. Some demographic and socio-economic factors exerted important influences on the attitudes of respondents. This study suggests that the project should continue addressing local development needs, encourage women's participation in community forestry, work toward dispute settlement of community forest-user groups, and allow hunting of pest wild animals, if it wants to win the support of local communities for long-term biodiversity conservation goals.
The vegetation of granite rock outcrops in Rio de Janeiro, Brazil, and the need for its protection
Authors: MEIRELLES SERGIO TADEU , PIVELLO VÂNIA REGINA , JOLY CARLOS ALFREDO
Published: July 2002

Rock outcrop communities usually receive very little attention from scientists and environmentalists. We examined the vegetation occurring in eight gneiss-granite rock outcrops at Rio de Janeiro State (Brazilian Atlantic coast) which exists in natural associations on soil islands. A total of 86 vascular plant species, belonging to 30 families, was found on 347 soil islands. Bromeliaceae, Asteraceae and Velloziaceae species were the most frequent plants, many of them endemic to these habitats. Ordination and cluster analyses using species frequency on each site made evident some major distinctions related to local influences, most probably the proximity to the sea. Each outcrop presented high values of the Shannon-Wiener index of species diversity. Species richness was very dependent on the total area, and high beta diversity was observed amongst sites. Similarities with the South American and African rock-outcrop communities were found. Despite their uniqueness as habitats, their possession of several endemic species and the fragility of the ecosystem involved, Brazilian rock outcrops are not protected by specific environmental legislation and we propose urgent actions for their protection.
Predictions of the emergence of vaccine-resistant hepatitis B
in The Gambia using a mathematical model
Authors: WILSON J. N. , NOKES D. J. , CARMAN W. F.
Published: July 2002

Vaccine escape variants of hepatitis B virus (HBV) have been identified world-wide. A
mathematical model of HBV transmission is used to investigate the potential pattern of
emergence of such variants. Attention is focused on The Gambia as a country with high
quality epidemiological data, universal infant immunization and in which escape mutants after
childhood infections have been observed. We predict that a variant cannot become dominant
for at least 20 years from the start of vaccination, even when using a vaccine which affords no
cross protection. The dominant factor responsible for this long time scale is the low rate of
infectious contacts between infected and susceptible individuals (we estimate the basic
reproduction number of hepatitis B in The Gambia to be 1·7). A variant strain that achieves
high prevalence will also take many years to control, and it is questionable whether emergence
will be identifiable by sero-surveillance until of high prevalence. The sensitivity of the model
predictions to epidemiological and demographic factors is explored.
The prevalence and genetic diversity of hepatitis C infection in antenatal clinic attenders in two regions of England
Authors: BALOGUN M. A. , RAMSAY M. E. , PARRY J. V. , DONOVAN L. , ANDREWS N. J. , NEWHAM J. A. , CLIFFE S. , HARRIS K. A. , TEO C.-G.
Published: July 2002

The prevalence and genetic diversity of hepatitis C infection in women attending antenatal
clinics in two regions of England was investigated to inform future surveillance and control
measures. Women booking into antenatal care are routinely offered a test for immunity to
rubella. Serum residues from these tests were unlinked, anonymized and archived as part of the
Unlinked Anonymous Prevalence Monitoring Programme (UAPMP). The serum specimens
were tested for anti-HCV using a cost-effective pooling strategy. After taking into account
differential sampling from the UAPMP serum archive, the adjusted overall prevalence of anti-HCV
was 0·43% (95% CI: 0·32–0·53) in London and 0·21% (95% CI: 0·14–0·28) in the
Northern and Yorkshire region. Restriction fragment length polymorphism of amplified HCV
RNA identified type 3a as the most common HCV genotype in these antenatal women. The
prevalence of anti-HCV in antenatal women in the UK is low and consistent with that
expected from injecting drug use.
The magnitude of variation in temperature within a year has an effect on the seasonal variations of chickenpox incidence in Japan
Authors: KOKAZE A. , YOSHIDA M. , SEKINE Y. , ISHIKAWA M. , KUROKOCHI T. , UCHIDA Y. , MATSUNAGA N. , TAKASHIMA Y.
Published: July 2002

We investigated the epidemic pattern of chickenpox incidence among 47 prefectures in Japan. There were two peaks in chickenpox incidence in all prefectures. The first peaks appear at almost the same time in a year, while the second peaks occur at different times with relatively different types of size and shape. The feature of the second peak might characterize the epidemic pattern of chickenpox. We first introduced the second peak index, that is, the ratio of the difference between the incidence at the point of the second peak and the minimum incidence between the first and second peaks to the difference between the incidence at the point of the second peak and the minimum incidence in the year. There was a close correlation between the second peak index and the magnitude of variation in temperature within a year corresponding to the difference between the maximum and the minimum of the monthly mean of the highest daily temperature. This is the first article focusing on the close relationship between the second peak of epidemic pattern of chickenpox incidence and the variation of temperature within a year.
A longitudinal study of an endemic disease in its wildlife reservoir: cowpox and wild rodents
Authors: HAZEL S. M. , BENNETT M. , CHANTREY J. , BOWN K. , CAVANAGH R. , JONES T. R. , BAXBY D. , BEGON M.
Published: July 2002

Cowpox is an orthopoxvirus infection endemic in European wild rodents, but with a wide host
range including human beings. In this longitudinal study we examined cowpox in two wild
rodent species, bank voles Clethrionomys glareolus and wood mice Apodemus sylvaticus, to
investigate the dynamics of a virus in its wild reservoir host. Trapping was carried out at
4-weekly intervals over 3 years and each animal caught was uniquely identified, blood sampled
and tested for antibodies to cowpox. Antibody prevalence was higher in bank voles than in
wood mice and seroconversion varied seasonally, with peaks in autumn. Infection was most
common in males of both species but no clear association with age was demonstrated. This
study provides a model for studying other zoonotic infections that derive from wild mammals
since other approaches, such as one-off samples, will fail to detect the variation in infection
and thus, risk to human health, demonstrated here.
Host adapted serotypes of Salmonella enterica
Authors: UZZAU S. , BROWN D. J. , WALLIS T. , RUBINO S. , LEORI G. , BERNARD S. , CASADESÚS J. , PLATT D. J. , OLSEN J. E.
Published: July 2002

Salmonella constitutes a genus of zoonotic bacteria of
worldwide economic and health importance. The
current view of salmonella taxonomy assigns the
members of this genus to two species: S. enterica and
S. bongori. S. enterica itself is divided into six
subspecies, enterica, salamae, arizonae, diarizonae,
indica, and houtenae, also known as subspecies I, II,
IIIa, IIIb, IV, and VI, respectively [1]. Members of
Salmonella enterica subspecies enterica are mainly
associated with warm-blooded vertebrates and are
usually transmitted by ingestion of food or water
contaminated by infected faeces. The pathogenicity of
most of the distinct serotypes remains undefined, and
even within the most common serotypes, many
questions remain to be answered regarding the
interactions between the organism and the infected
host.

Salmonellosis manifests itself in three major forms:
enteritis, septicaemia, and abortion, each of which
may be present singly or in combination, depending
on both the serotype and the host involved. Although
currently over 2300 serovars of Salmonella are
recognized, only about 50 serotypes are isolated in
any significant numbers as human or animal
pathogens [2, 3] and they all belong to subspecies
enterica. Of these, most cause acute gastroenteritis
characterized by a short incubation period and a
severe systemic disease in man or animals, characterized by septicaemia, fever and/or abortion, and
such serotypes are often associated with one or few
host species [4–6].

It is the intention of this review to present a
summary of current knowledge of these host-adapted
serotypes of S. enterica. The taxonomic relationships
between the serotypes will be discussed together with
a comparison of the pathology and pathogenesis of
the disease that they cause in their natural host(s).
Since much of our knowledge on salmonellosis is
based on the results of work on Typhimurium, this
serotype will often be used as the baseline in
discussion. It is hoped that an appreciation of the
differences that exist in the way these serotypes
interact with the host will lead to a greater understanding of the complex host–parasite relationship
that characterizes salmonella infections.
HCV prevalence in pregnant women in the UK
Authors: ADES A. E. , PARKER S. , WALKER J. , CUBITT W. D. , JONES R.
Published: July 2002

The objective of the study was to assess the prevalence and epidemiology of hepatitis C virus
(HCV) infection in pregnant women in the North Thames region, and in the UK in general.
Demographic data were linked to neonatal samples prior to anonymization and testing by anti-HCV
EIA, and with RIBA 3 confirmation. Risk factors for maternal infection were explored.
Area-specific seroprevalence rates were multiplied into population sizes to estimate HCV
prevalence in pregnant women in the UK. A total of 241/126009 samples were confirmed anti-HCV
positive, and a further 40 were indeterminate, representing a seroprevalence of
0·19–0·22%; 51% of maternal HCV infections were in UK-born women (71% of the
population), and 22% in women from continental Europe (5% of the population). Among
European-born women, HCV prevalence was associated with birth in continental Europe,
partner not being notified at birth registration, partner born in a different region to the
mother, and inner city residence. Four of the 241 anti-HCV positive samples (1·7%) were also
anti-HIV-1 positive. It was estimated that each year an estimated 1150 out of 730000
pregnancies in the UK would involve a woman infected with HCV (uncertainty range
660–1850), a prevalence of 0·16% (0·09–0·25%). On the basis of reported rates of mother-to-child
transmission of HCV, this would represent approximately 70 paediatric HCV infections
per year.
The diet and landclass affinities of the Irish hare Lepus timidus hibernicus
Authors: Dingerkus S. K. , Montgomery W. I.
Published: July 2002

The diet of the Irish hare Lepus timidus hibernicus was investigated in Northern Ireland. Faecal pellets were collected at regular intervals from three contrasting study sites and from a number of randomly selected sites from known land classes. Microhistological techniques were employed to analyse the pellets. Grass species occurred in high percentage frequencies in all samples of faecal pellets and a wide variety of plant species were represented (up to 26 species in one study site). In a stratified, random survey of the presence of hares, areas of lowland intensive agriculture had fewer positive records than expected. It is contended that L. t. hibernicus may not be able to sustain viable populations in areas of intensive agriculture, which are almost exclusively composed of ryegrass Lolium spp.
The behavioural ecology of the island fox (Urocyon littoralis)
Authors: Roemer Gary W. , Smith Deborah A. , Garcelon David K. , Wayne Robert K.
Published: July 2002

Insular populations typically occur at higher densities, have higher survivorship, reduced fecundity, decreased dispersal, and reduced aggression compared to their mainland counterparts. Insularity may also affect mating system and genetic population structure. However, these factors have not been examined simultaneously in any island vertebrate. Here we report on the ecological, behavioural and genetic characteristics of a small carnivore, the island fox Urocyon littoralis, from Fraser Point, Santa Cruz Island, California. Dispersal distances in island foxes are very low (mean 1.39 km, sd 1.26, range 0.16–3.58 km, n=8). Home‐range size is one of the smallest (mean annual home range=0.55 km2, sd 0.2, n= 14) and density is nearly the highest recorded for any canid species (2.4–15.9 foxes/km2). Similar to other fox species, island foxes are distributed as mated pairs that maintain discrete territories. Overlap among mated pairs was always high (mean 0.85, sd 0.05), while overlap among neighbours (mean 0.11, sd 0.13), regardless of sex, was low. Despite this high degree of territoriality, island foxes are not strictly monogamous. Four of 16 offspring whose parents were identified by paternity analysis were a result of extra‐pair fertilizations. Mated pairs were unrelated, however, suggesting inbreeding avoidance. Substantial population differentiation was found between the Fraser Point subpopulation and one only 13 km away (Fst= 0.11). We suggest that the primary effect of finite island area is to limit dispersal, which then influences the demography, behaviour and genetic structure of island fox populations.
Emotion management skills in sexually maltreated and nonmaltreated girls: A
developmental psychopathology perspective
Authors: SHIPMAN KIMBERLY , ZEMAN JANICE , PENZA SUSAN , CHAMPION KELLY
Published: July 2002

Research has demonstrated that children who experience familial sexual maltreatment are at
risk for developing psychological difficulties characterized by emotional and behavioral
dysregulation. Surprisingly, however, little attention has been directed toward identifying
processes in emotional development that differ in maltreated and nonmaltreated children. From a
developmental psychopathology perspective, the present study examined emotion management
skills (i.e., emotional understanding, emotion regulation) in 21 sexually maltreated girls and their
nonmaltreated peers to determine how the experience of sexual maltreatment may interfere with
normative emotional development. Findings indicated that sexually maltreated girls, in
comparison to their nonmaltreated peers, demonstrate lower emotional understanding and
decreased ability to regulate their emotions in accordance with cultural expectations. Further,
maltreated girls expected less emotional support and more relational conflict from parents in
response to sadness displays and from parents and peers in response to anger displays. These
findings will be discussed from the functionalist approach to emotional development,
emphasizing the importance of social context (e.g., maltreating, nonmaltreating) in the
development of children's emotion management skills.
Stigma and mental disorder: Conceptions of illness, public attitudes, personal disclosure, and

social policy
Authors: HINSHAW STEPHEN P. , CICCHETTI DANTE
Published: July 2002

The end of the last millennium witnessed an unprecedented degree of public awareness

regarding mental disorder as well as motivation for policy change. Like Sartorius, we contend that

the continued stigmatization of mental illness may well be the central issue facing the field, as

nearly all attendant issues (e.g., standards of care, funding for basic and applied research efforts)

emanate from professional, societal, and personal attitudes towards persons with aberrant

behavior. We discuss empirical and narrative evidence for stigmatization as well as historical

trends regarding conceptualizations of mental illness, including the field's increasing focus

on genetic and neurobiological causes and determinants of mental disorder. We next define stigma

explicitly, noting both the multiple levels (community, societal, familial, individual) through which

stigma operates to dehumanize and delegitimize individuals with mental disorders and the impact

of stigma across development. Key developmental psychopathology principles are salient in this

regard. We express concern over the recent oversimplification of mental illness as “brain

disorder,” supporting instead transactional models which account for the dynamic interplay

of genes, neurobiology, environment, and self across development and which are consistent with

both compassion and societal responsibility. Finally, we consider educational and policy-related

initiatives regarding the destigmatization of mental disorder. We conclude that attitudes and

policy regarding mental disorder reflect, in microcosmic form, two crucial issues for the next

century and millennium: (a) tolerance for diversity (vs. pressure for conformity) and (b)

intentional direction of our species' evolution, given fast-breaking genetic advances.
Low cortisol and a flattening of expected daytime rhythm: Potential indices of risk in human
development
Authors: GUNNAR MEGAN R. , VAZQUEZ DELIA M.
Published: July 2002

Since the work of Hans Selye, stress has been associated with increased activity of the
limbic–hypothalamic– pituitary–adrenocortical (LHPA) axis. Recently, a
number of studies in adults have shown that this neuroendocrine axis may be hyporesponsive in a
number of stress-related states. Termed hypocortisolism, the paradoxical suppression of the
LHPA axis under conditions of trauma and prolonged stress presently challenges basic concepts in
stress research. Adverse conditions that produce elevated cortisol levels early in life are
hypothesized to contribute to the development of hypocortisolism in adulthood. However, as
reviewed in this paper, hypocortisolism also may be a common phenomenon early in human
childhood. Although preliminary at this point, the ubiquity of these findings is striking. We argue
that developmental studies are needed that help explicate the origins of low cortisol and to
determine whether the development of hypocortisolism is, in fact, preceded by periods of frequent
or chronic activation of the LHPA axis. We also argue that developmental researchers who
incorporate measures of salivary cortisol into their studies of at-risk populations need to be aware
of the hypocortisolism phenomenon. Lower than expected cortisol values should not necessarily
be relegated to the file drawer because they contradict the central dogma that stress must be
associated with elevations in cortisol. Lastly, we note that evidence of low cortisol under adverse
early life conditions in humans adds to the importance of understanding the implications of
hypocortisolism for health and development.
The relationship between joint attention and pretend play in autism
Authors: CHARMAN TONY
Published: July 2002

There is considerable evidence that the development of joint
attention and pretend play skills are impaired in children with
autism. Some accounts of autistic psychopathology give a crucial role
to early impairments in joint attention and suggest that these lead to
impoverished development of the representational abilities that
underlie the later emerging impairments in pretend play and theory of
mind. Other accounts of impairments in joint attention and pretend
play see them merely as symptoms of a more basic underlying cognitive
deficit, in attention or executive function. This review examines the
evidence for the possible relationships that may exist between joint
attention and pretend play and the later development of a theory of
mind. It also suggests directions for future work to clarify the
relationship between the two skills and to identify the nature of the
underlying primary deficit in autism.
Interparental conflict and relations with parents as predictors of young adult functioning
Authors: NEIGHBORS BRYAN D. , FOREHAND REX , BAU JINN-JONP
Published: July 2002

Interparental conflict is a known risk factor for child adjustment
problems; yet few studies have examined its long-term effects. This
study tests the following hypotheses: Interparental conflict has both
longitudinal and concurrent influences on the functioning of young
adult children, and the relationship between young adults and their
parents mediates these influences. We assessed a community sample
(N = 243) of families when the target child was in early to
middle adolescence. We then reassessed them 6 years later during young
adulthood. The links of interparental conflict measured at the two
time points to young adults' general psychopathology and
antisocial behavior were examined using multiple regression
analyses. The quality of the relationship between young adults and
each parent was added to each equation as a potential mediating
variable. Results showed that concurrent, but not earlier,
interparental conflict predicted males' antisocial behavior. No
support was found for the mediational model, but support was found for
an alternate model positing direct effects for interparental conflict
and the parent-young adult relationship on young adult
functioning. For females and males, problematic relationships with
mothers and fathers predicted greater general psychopathology, while
problems in paternal relationships predicted higher levels of
antisocial behavior only for females.
Representations of self and other in the narratives of neglected, physically abused, and

sexually abused preschoolers
Authors: TOTH SHEREE L. , CICCHETTI DANTE , MACFIE JENNY , EMDE ROBERT N.
Published: July 2002

The MacArthur Story Stem Battery was used to examine maternal and self-representations in

neglected, physically abused, sexually abused, and nonmaltreated comparison preschool children.

The narratives of maltreated children contained more negative maternal representations and more

negative self-representations than did the narratives of nonmaltreated children. Maltreated

children also were more controlling with and less responsive to the examiner. In examining the

differential impact of maltreatment subtype differences on maternal and self-representations,

physically abused children evidenced the most negative maternal representations; they also had

more negative self-representations than nonmaltreated children. Sexually abused children

manifested more positive self-representations than neglected children. Despite these differences

in the nature of maternal and self-representations, physically and sexually abused children both

were more controlling and less responsive to the examiner. The investigation adds to the corpus

of knowledge regarding disturbances in the self-system functioning of maltreated children and

provides support for relations between representational models of self and other and the

self-organizing function that these models exert on children's lives.