bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing productive vocabulary measures from the
CDI and a systematic diary study
Authors: ROBINSON BYRON F. , MERVIS CAROLYN B.
Published: July 2002

Expressive vocabulary data gathered during a systematic diary study
of
one male child's early language development are compared to data that

would have resulted from longitudinal administration of the MacArthur
Communicative Development Inventories spoken vocabulary checklist
(CDI). Comparisons are made for (1) the number of words at monthly
intervals (9;10.15 to 2;0.15), (2) proportion of words by lexical class
(i.e.
noun, predicate, closed class, ‘other’), (3) growth curves.
The CDI
underestimates the number of words in the diary study, with the
underestimation increasing as vocabulary size increases. The proportion

of diary study words appearing on the CDI differed as a function of
lexical class. Finally, despite the differences in vocabulary size, logistic

curves proved to be the best fitting model to characterize vocabulary
development as measured by both the diary study and the CDI.
Implications for the longitudinal use of the CDI are discussed.
Understanding the modelling endeavour
Authors: PLUNKETT KIM , ELMAN JEFFREY L. , BATES ELIZABETH
Published: July 2002

We enjoyed reading Matthew Rispoli's review of Rethinking
innateness
(henceforth RI-Elman et al. 1996). First, we respond to what we
see as the
major issues that he raises. Finally, we respond to the commentaries
contributed by other authors in this issue.

Rispoli has two major concerns. First, he fears that RI will do the
field a
great disservice, increasing polarization and sowing discontent. To some

extent this is an ‘eye of the beholder’ criticism that is difficult
to counter: if
Rispoli feels more polarized upon reading this book, who are we to argue?
Uniqueness in two-dimensional rigidity percolation
Authors: HÄGGSTRÖM OLLE
Published: July 2002

For bond percolation on the two-dimensional triangular lattice with arbitrary
retention parameter p ∈ [0, 1], we show that the number of infinite rigid components
is a.s. at most 1. This proves a conjecture by Holroyd. Further results, concerning
simultaneous uniqueness, and continuity (in p) of the probability that a given edge
is in an infinite rigid component, are also obtained.
Cap-product structures on the Fintushel–Stern spectral sequence
Authors: LI WEIPING
Published: July 2002

We show that there is a well-defined cap-product structure on the Fintushel–Stern
spectral sequence and the induced cap-product structure on the ℤ8-graded instanton
Floer homology. The cap-product structure provides an essentially new property of
the instanton Floer homology, from a topological point of view, which multiplies a
finite-dimensional cohomlogy class by an infinite-dimensional homology class (Floer
cycles) to get another infinite-dimensional homology class.
Fractional integration, differentiation, and weighted Bergman spaces
Authors: BUCKLEY STEPHEN M. , KOSKELA PEKKA , VUKOTIĆ DRAGAN
Published: July 2002

We study the action of fractional differentiation and integration
on weighted
Bergman spaces and also the Taylor coeffficients of functions in certain
subclasses of
these spaces. We then derive several criteria for the multipliers between
such spaces,
complementing and extending various recent results. Univalent Bergman functions

are also considered.
Some remarks on universal functions and Taylor series
Authors: COSTAKIS G.
Published: July 2002

We derive properties of universal functions and Taylor series in domains of the
complex plane. For some of our results we use Baire's theorem. We also give a constructive
proof, avoiding Baire's theorem, of the existence of universal Taylor series
in any arbitrary simply connected domain.
Capability Prediction: An Effective
Way to Improve Navigational Performance
Authors: van Breda Leo
Published: July 2002

The potential benefit of predictive information for navigation support was investigated in a
simulator study. Twelve participants had to guide a medium-size vessel across a traffic
separation scheme. In the simulator, critical vessel traffic scenarios were created, where
participants were provided with: (i) baseline Automatic Radar Plotting Aid (ARPA)
information, and (ii) baseline ARPA information supplemented with capability prediction
information. This is information that shows the predicted manoeuvring margins of the
vessel, indicating the predicted boundaries of safe operation. Results of the experiment
indicate that capability prediction allows better anticipation by the navigator, significantly
improving ship navigation performance.
Institutional Aspects of a Global Navigation Satellite System
Authors: Brocklebank D. , Spiller J. , Tapsell T.
Published: July 2002

This, and the following three papers, where first presented at GNSS 99, the Second European
Symposium on Global Navigation Satellite Systems held in Genoa, Italy from 5th to 8th
October 1999.

Galileo is being developed as the European contribution to the next generation of navigation
satellites to replace GNSS1. Sponsored by the European Union, Galileo will be a civil,
internationally controlled and operated system that will secure the long-term availability of
satellite-based navigation services for multi-modal purposes throughout the European region
and beyond. Galileo will be designed to support a wide variety of applications. These include
professional navigation, position reference, safety, emergency, tracking, sport/leisure and
governmental. Such services may be open to all, for safety-of-life applications, or for
commercial users. In the case of safety and commercial applications in particular, it is
imperative that the appropriate institutional control and regulatory framework is in place for
purposes of safety and economic regulation. To ensure that the various parties understand
their obligations and liabilities, clear legal instruments must be put in place to support the
organisational framework. It is planned to attract private investment to fund elements of
system development and operation through Private/Public Partnership arrangements. At
present there is no institutional, regulatory or legal framework that will enable the early
impetus to Galileo development to be maintained. This presents a challenge that Europe
must address without delay. It has been the subject of several European Commission studies
in the past twelve months. In a complementary activity under contract to the European
Space Agency (ESA), a European industry consortium comprising Alcatel, Alenia, DASA
and Matra Marconi Space was tasked to complete the preliminary design of the space and
ground segments by the Autumn of 1999. One task of this study, led by Matra Marconi
Space, relates to a study of the impact of institutional, regulatory and legal issues on the
organisation and development of Galileo. This paper describes the studies undertaken into
these issues within the overall Galileo development programme.
Planning of Future Satellite
Navigation Systems
Authors: Spiller John , Tapsell Tony , Peckham Richard
Published: July 2002

This paper is based on the results of the ‘GNSS Support
Task’ study for the European
Commission, DGXIII. It summarises the results of the cost benefit analysis
in terms of
coverage, accuracy and safety requirements for different types of user
and describes the most
cost-effective GNSS 2 architecture. These analyses also assume that the
overall system is
layered into wide area, regional and local systems. The future planning
of satellite navigation
is essentially driven by the wide area requirements and ensuring that these
are global and
seamless. There is some flexibility in coverage and accuracy for a wide
area system in that
it can be augmented regionally or locally if required, but it must provide
the highest level of
safety required. The paper approaches the architecture for a future navigation
system from
this safety aspect. An analysis of the chosen architecture shows that the
required safety
performance can be met. An implementation plan is described which allows
a gradual
evolution from the first system to be realized for safety critical operations
to a fully civilian
owned and operated system.
Incommensurable preferences in contingent valuation: the case of Natura 2000 Network in Finland
Authors: REKOLA M. , POUTA E. , KUULUVAINEN J. , TAHVONEN O. , LI C.-Z.
Published: July 2002

In the literature of contingent valuation, a rights-based system of environmental ethics claiming that natural objects have absolute rights, has frequently been regarded as the main reason for incommensurability, i.e. for citizens’ inability to find a common measure according to which all values could be ranked. In a study of 2400 Finns aged between 18 and 70, we tested whether a respondent's commitment to guaranteeing private property rights could be a reason for incommensurability beyond the respondent's possible commitment to absolute nature rights. It was found that incommensurability, modelled with lexicographic preferences, was attributable more often to private property rights than to nature rights. However, Finnish respondents who had lexicographic preferences for nature rights based their choice more often on an ethical judgement, whereas lexicographic preferences for property rights could rather be explained with an ambivalent preference construction. Lexicographic preferences for nature rights increased the willingness to pay for conservation, while lexicographic preferences for property rights decreased it. The result, which was predicted by the theory, supported the validity of incommensurability measurement. The study therefore indicates that several reasons for incommensurable preferences may exist and that it is possible to measure these reasons in contingent valuation surveys in order to judge the validity of the welfare measures in environmental policy decision-making.
Ethics and environmental conservation
Authors: TROMPF GARRY W.
Published: July 2002

After addressing a conference on ‘Ethics and the Practising Scientist’ some four years back, I remember the conferees struggling to formulate a code of ethics for those engaged in the so-called ‘hard’ sciences. They could not arrive at a satisfactory formulation, and at one point the chairman, in utter exasperation, confessed that, he didn't care for details about principles or quibbles over which slant the statements took, for ‘frankly any code should do!’ During the decade before and after that 1993 meeting, attempts to enunciate moral principles for researchers and manifestos for responsibility in science have come and gone, and the notes of discord have not abated.
Reply: Protected areas and property rights in Thailand
Authors: VANDERGEEST PETER
Published: July 2002

Dearden et al . (1998) have suggested that my arguments for backing away from zealously pursuing the expansion of protected areas in Thailand (Vandergeest 1996) means giving benefits to local people with no consideration for the wider community or future generations. Let me begin my response by reminding readers of my central argument: that the driving force behind the rapid expansion of wildlife sanctuaries and national parks in Thailand was primarily the forest department's need to find new ways of controlling territory and legitimizing budget allocations, rather than nature protection per se. This bureaucratic need was the outcome of widespread occupation of reserve forests, due to both reservation of occupied areas and new migration into demarcated reserved forests, as well as the 1989 ban on legal logging in Thailand. In its rush to convert reserve forest to protected area status, the forest department demarcated as national parks and wildlife sanctuaries many areas occupied and used by local people, producing a situation in which most protected areas in Thailand are surrounded or partially occupied by an alienated local population who feel that their legitimate property rights have been appropriated. The rapid expansion of protected areas in Thailand is thus hardly something that the international conservation community should be celebrating. Nor will ongoing problems with local people be fundamentally resolved through development projects, buffer zones, and participatory conservation alone, although these kinds of projects often have important benefits. I suggested that a more appropriate direction would be to degazette and allocate to households land clearly claimed and occupied by rural households, which I estimate to be about 20% of protected areas. I also suggested that some land gazetted as protected area could be managed as common property, and that conservation could be much more aggressively pursued outside of protected areas.
Design synthesis knowledge and inductive machine learning
Authors: POTTER S. , DARLINGTON M.J. , CULLEY S.J. , CHAWDHRY P.K.
Published: July 2002

A crucial early stage in the engineering design process is
the conceptual design phase, during which an initial solution
design is generated. The quality of this initial design has
a great bearing on the quality and success of the produced
artefact. Typically, the knowledge required to perform this
task is only acquired through many years of experience, and
so is often at a premium. This has led to a number of attempts
to automate this phase using intelligent computer systems. However,
the knowledge of how to generate designs has proved difficult
to acquire directly from human experts, and as a result, is
often unsatisfactory in these systems. The application of inductive
machine learning techniques to the acquisition of this sort
of knowledge has been advocated as one approach to overcoming
the difficulties surrounding its capture. Rather than acquiring
the knowledge from human experts, the knowledge would be inferred
automatically from a set of examples of the design process.
This paper describes the authors' investigations into the
general viability of this approach in the context of one particular
conceptual design task, that of the design of fluid power circuits.
The analysis of a series of experiments highlights a number
of issues that would seem to arise regardless of the working
domain or particular machine learning algorithm used. These
issues, presented and discussed here, cast serious doubts upon
the practicality of such an approach to knowledge acquisition,
given the current state of the art.
Toward analysis tools for the engineering process
Authors: LEVITT RAYMOND E.
Published: July 2002

Rapid development and delivery of high-performance,
high-quality new products is the key to survival and success
for many firms in today's high technology, global
marketplace. However, shrinking time to market for complex,
high technology products can be extremely difficult and
costly. Even the most successful engineering managers have
experienced the escalating costs of overtime, coordination
and rework that are so common in fast-track, high technology,
product development efforts; and they know the quality problems
that can result when coordination breaks down in the face of
aggressive—often “impossible”—development
schedules.
Dimensions of machine learning in design
Authors: GRECU DAN L. , BROWN DAVID C.
Published: July 2002

Many of the design systems developed in recent
years incorporate some machine learning. The number of
such systems already available, and the multitude of design
learning opportunities that are slowly being revealed,
suggest that the time is ripe to attempt to put these developments
into a systematic framework. Consequently, in this paper
we present a set of dimensions for machine learning in
design research. We hope that it can be used as a guide
for comparing existing work, and that it may suggest new
directions for future exploration in this area.
Optimal design of flywheels using an injection island genetic
algorithm
Authors: EBY DAVID , AVERILL R.C. , PUNCH WILLIAM F. , GOODMAN ERIK D.
Published: July 2002

This paper presents an approach to optimal design
of elastic flywheels using an Injection Island Genetic
Algorithm (iiGA), summarizing a sequence of results reported
in earlier publications. An iiGA in combination with a
structural finite element code is used to search for shape
variations and material placement to optimize the Specific
Energy Density (SED, rotational energy per unit weight)
of elastic flywheels while controlling the failure angular
velocity. iiGAs seek solutions simultaneously at different
levels of refinement of the problem representation (and
correspondingly different definitions of the fitness function)
in separate subpopulations (islands). Solutions are sought
first at low levels of refinement with an axi-symmetric
plane stress finite element code for high-speed exploration
of the coarse design space. Next, individuals are injected
into populations with a higher level of resolution that
use an axi-symmetric three-dimensional finite element code
to “fine-tune” the structures. A greatly simplified
design space (containing two million possible solutions)
was enumerated for comparison with various approaches that
include: simple GAs, threshold accepting (TA), iiGAs and
hybrid iiGAs. For all approaches compared for this simplified
problem, all variations of the iiGA were found to be the
most efficient. This paper will summarize results obtained
studying a constrained optimization problem with a huge
design space approached with parallel GAs that had various
topological structures and several different types of iiGA,
to compare efficiency. For this problem, all variations
of the iiGA were found to be extremely efficient in terms
of computational time required to final solution of similar
fitness when compared to the parallel GAs.
Initially unrecognized distribution of a commercially cooked meat product contaminated over several months with Salmonella serotype Infantis
Authors: KOHL K. S. , FARLEY T. A.
Published: July 2002

An outbreak of salmonellosis occurred among 63 wedding participants. The outbreak was
investigated through cohort, laboratory, and environmental studies. Consumption of rice-dressing
made from a commercially cooked, meat-based, rice-dressing mix was strongly
associated with illness. Nineteen patient isolates, six company/grocery store isolates cultured
from the rice-dressing mix, and one environmental isolate from a pump in the production line
were of an identical outbreak strain of Salmonella Infantis characterized by pulsed-field gel
electrophoresis. In the production line, cooked rice-dressing mix tested negative for S. Infantis
before and positive after contact with the contaminated pump. The dressing-mix had an
estimated 200 colony-forming units of salmonella per gram of product, and > 180 000 pounds
were distributed in 9 states for [ges ] 2 months before contamination was recognized. Food
manufacturers should be required to use systematic, hazard analysis critical control point risk
management practices for all processed meat products, validated by periodic microbiologic
monitoring of the end product.
Epidemiology of varicella in Slovenia over a 20-year period (1979–98)
Authors: SOČAN M. , KRAIGHER A. , PAHOR L.
Published: July 2002

Varicella is one of the most common childhood diseases. The course of the disease is usually mild and uncomplicated. In Slovenia, varicella is a notifiable communicable disease which must be reported. Data collected from 1979–98 were analysed. Over the 20-year period the number of varicella cases reported ranged from a low of 11 086 (in 1994) to a maximum of 21 141 (in 1987). During the last 10 years, the highest incidence of varicella was reported in children aged from 12 months to 2 years. In adults over 20, incidence has slightly but steadily increased over the 20 year period. Overall, the number of males with varicella exceeded that of females. The proportion of females was higher only in the 20–30-year age group, probably as a consequence of more frequent and closer contact with infected children by mothers. The highest number of reported cases was during winter and early spring.
The natural history of tuberculosis: the implications of

age-dependent risks of disease and the role of reinfection
Authors: VYNNYCKY E. , FINE P. E. M.
Published: July 2002

Many aspects of the natural history of tuberculosis are poorly

understood. Though it is

recognized that clinical tuberculosis may follow shortly after initial

infection (‘primary’

disease), or many years thereafter through either endogenous reactivation
or

after reinfection,

the relative importance of these mechanisms is often disputed. The issue

is complicated by the

fact that the risks of developing disease are age-dependent, and reflect

infection risks which may change over time.

This paper estimates the age-dependent risks of developing tuberculosis

using an age-structured deterministic model of the dynamics of tuberculous

infection and disease in England

and Wales since 1900. The work extends the classical studies of Sutherland

and colleagues. The

best estimates of the risks of developing ‘primary’ disease

(within 5 years of initial infection)

were approximately 4%, 9% and 14% for individuals infected at ages

0–10, 15 years and over

20 years respectively, and a previous infection appeared to impart little

protection against (further) reinfection, but 16–41% protection against
disease

subsequent to reinfection for

adolescents and adults. We also provide evidence that reinfection made
an important

contribution to tuberculous morbidity in the past, as (i) exclusion

of exogenous disease from

the model considerably worsened the fit to observed notification

rates, and (ii) the dramatic

decline in the risk of tuberculous infection from 1950 in England and

Wales accelerated the

decline in morbidity among all individuals, even among the

older age groups with a high

prevalence of tuberculous infection. We conclude that the risk of infection

is the single most

important factor affecting the magnitude of the tuberculous morbidity in

a population, as it

determines both the age pattern of initial infection (and hence the risk

of developing disease) and the risk of reinfection.
Salmonella infections in Norway: descriptive epidemiology
and a case-control study
Authors: KAPPERUD G. , LASSEN J. , HASSELTVEDT V.
Published: July 2002

The epidemiological progression of human salmonellosis in Norway
is parallel to trends noted
elsewhere in Europe. During the past two decades, the number of reported
cases has increased
steadily, with a special sharp rise in the early 1980s due to the emergence
of Salmonella
enteritidis, followed by a levelling off in recent years. However,
in contrast to the situation in
most other European countries, about 90% of the cases from whom a travel
history is
available, have acquired their infection abroad. The incidence of indigenous
salmonella
infections as well as the prevalence of the microorganism in the domestic
food chain, are both
comparatively low. In 1993–4, a national case-control study of sporadic
indigenous salmonella
infections was conducted to identify preventable risk factors and guide
preventive efforts.
Ninety-four case patients and 226 matched population controls were enrolled.
The study failed
to demonstrate any statistically significant association between salmonellosis
and consumption
of domestically produced red meat, poultry or eggs. The only factor which
remained
independently associated with an increased risk in conditional logistic
regression analysis, was
consumption of poultry purchased abroad during holiday visits to neighbouring
countries. A
separate analysis of Salmonella typhimurium infections incriminated
food from catering
establishments and foreign travel among household members, in addition
to imported poultry.
Previous respiratory tract infections and antibiotic
consumption in children with long- and short-term carriage of
penicillin-resistant Streptococcus pneumoniae
Authors: GUNNARSSON O. , EKDAHL K.
Published: July 2002

Previous respiratory tract infections (RTI) and antibiotics consumption
as possible risk factors
for extended duration of PRP carriage were investigated in 24 children
(cases) with previous
carriage of penicillin-resistant pneumococci (PRP) for a duration exceeding
120 days (median
168 days) and a control group of 53 children with a duration of PRP carriage
less than 90
days (median 21 days). The cases had experienced 0·99 episodes of
acute otitis media (AOM)
per life-year compared to 0·79 episodes in the controls (P=0·32).
For antibiotic-treated RTI
other than AOM, the corresponding numbers were 0·49 and 0·29
episodes per life-year,
respectively (P=0·01). No differences in antibiotic consumption
in the 3 months preceding the
carriage, nor during the carriage period were noted. Other factors than
impaired host defence
to respiratory tract pathogens or antibiotics consumption seem to be more
important in
determining the duration of PRP carriage.
Ribotypes of clinical Vibrio cholerae non-O1 non-O139
strains in relation to O-serotypes
Authors: DALSGAARD A. , FORSLUND A. , MORTENSEN H. F. , SHIMADA T.
Published: July 2002

The emergence of Vibrio cholerae O139 in 1992 and reports
of an increasing number of other
non-O1 serogroups being associated with diarrhoea, stimulated us to characterize
V. cholerae
non-O1 non-O139 strains received at the National Institute of Infectious
Diseases, Japan for
serotyping. Ribotyping with the restriction enzyme BglI of 103
epidemiological unrelated
mainly clinical strains representing 10 O-serotypes yielded 67 different
typing patterns.
Ribotype similarity within each serotype was compared by
using the Dice coefficient (Sd) and
different levels of homogeneity were observed (serotypes O5, O41 and O17,
Sd between 82 and
90%; serotypes O13 and O141 Sd of 72; and O2, O6, O7,
O11, O24 Sd of 62–66%). By
cluster analysis, the strains were divided into several clusters of low
similarity suggesting
a high level of genetic diversity. A low degree of similarity between serotypes
and ribotypes
was found as strains within a specific serotypes often did not cluster
but clustered with
strains from other serotypes. However, epidemiological unrelated O5 strains
showed identical
or closely related ribotypes suggesting that these strains have undergone
few genetic changes
and may correspond to a clonal line. Surprisingly, 10 of 16 O141 strains
studied contained
a cholera toxin (CT) gene, including 7 strains recovered from stool and
water samples
in the United States. This is to our knowledge the first report of CT-positive
clinical O141
strains. The closely related ribotypes shown by eight CT-positive strains
is disturbing and
suggest that these strains may be of a clonal origin and have
the potential to cause cholera-like
disease. Despite the low degree of correlation found between ribotypes
and serotypes, both
methods appears to be valuable techniques in studying the epidemiology
of emerging serotypes
of V. cholerae.
Is group C meningococcal disease increasing in Europe? A
report of surveillance of meningococcal infection in Europe
1993–6
Authors: CONNOLLY M. , NOAH N.
Published: July 2002

A surveillance system to assess the impact and changing epidemiology
of invasive
meningococcal disease in Europe was set up in 1987. Since about 1991, contributors
from
national reference laboratories, national communicable disease surveillance
centres and
institutes of public health in 35 European countries provided information
on all reported cases
of meningococcal disease in their country. We describe some trends observed
over the period
1993–6. The main findings were: the overall incidence of meningococcal
disease was 1·1 per
100000 population but there was some evidence of a slow increase over time
and with northern
European countries tending to have a higher incidence (Kendall correlation
0·5772, P<0·001),
an increasing predominance of serogroup C, and a shift in the age distribution
towards
teenagers and away from younger children (χ2 test
for trend 44·56, P<0·0001), although
about half of the cases were under 5 years of age. The overall case fatality
rate was 8·3% and
the most common serosubtypes were B[ratio ]15[ratio ]P1.7,16 and C[ratio ]2a[ratio ]P1.2,5.
Rotavirus infection in Hong Kong: epidemiology and
estimates of disease burden
Authors: CHAN P. K. S. , TAM J. S. , NELSON E. A. S. , FUNG K. S. C. , ADEYEMI-DORO F. A. B. , FOK T. F. , CHENG A. F.
Published: July 2002

Rotavirus gastroenteritis should soon be a vaccine-preventable
disease.
In a 10-year survey of
rotavirus gastroenteritis conducted at the Prince of Wales Hospital (PWH),
2281 cases were
detected of which 2213 (97%) occurred in children <5 years old. A consistent
epidemic
occurred each winter during the months of December and January. Of all
laboratory-confirmed
cases, 78% were community-acquired with a mean hospital stay of 4·7
days. The estimated
incidence of rotavirus-attributed hospitalization was 2/1000 children

<5 years old. Over the 10
years, rotavirus was responsible for one death, and contributory to three
other deaths. On
average each year, 195 children <5 years old were hospitalized for a
total of 917 days in
PWH, accounting for an estimated expenditure of HK$2·8 (∼US$0·4)
million on
hospitalization costs. The annual financial burden for rotavirus
gastroenteritis for the whole of
Hong Kong could be in excess of HK$9·6 (∼US$1·2) million.
Determinants of antibodies to Cryptosporidium infection
among gay and bisexual men with HIV infection
Authors: CAPUTO C. , FORBES A. , FROST F. , SINCLAIR M. I. , KUNDE T. R. , HOY J. F. , FAIRLEY C. K.
Published: July 2002

A cross-sectional serosurvey for markers of prior Cryptosporidium infection was conducted
among homosexual or bisexual males infected with human immunodeficiency virus (HIV); of
262 individuals approached, 236 (90%) agreed to participate. Serological response to two
Cryptosporidium antigens was measured using a Western blot assay. The intensity or detection
of serological responses to two Cryptosporidium antigens was not associated with CD4 cell
counts or tap water consumption. A number of sexual practices were related to increased
serological response for only the 27-kDa marker, including having had sex within the past 2
years, having anal sex and having had a larger number of sex partners during the past 2 years.
Attending a spa or sauna was related to serological response to both the 27-kDa and 17-kDa
markers. Based on these results, activities related to sexual activity appear to be a significant
risk factors for prior Cryptosporidium infection.
The epidemiology of head lice and scabies in the UK
Authors: DOWNS A. M. R. , HARVEY I. , KENNEDY C. T. C.
Published: July 2002

Anecdotal evidence suggests that the prevalence of both scabies and head lice is increasing and
also that both conditions are becoming refractory to pesticide treatment. Using information
obtained from the Office of National Statistics, Royal College of General Practitioners Weekly
Returns Service, Department of Health, local surveys of school children from Bristol and drug
sales of insecticides, we have confirmed that there has been a rise in the prevalence of both
conditions. We have shown that scabies is significantly more prevalent in urbanized areas
(P<0·00001), north of the country (P<0·000001),
in children and women (P<0·000001) and
commoner in the winter compared to the summer. Scabies was also shown to have a cyclical
rise in incidence roughly every 20 years. Head lice were shown to be significantly more
prevalent in children and mothers (P<0·000001)
though both conditions were seen in all age
groups. Head lice were also less common during the summer. Host behaviour patterns,
asymptomatic carriage, drug resistance and tourism from countries or districts with a higher
incidence may be important factors in the currently high prevalence of both scabies and head
lice.
Antimeningococcal herd immunity in the Czech Republic –
influence of an emerging clone, Neisseria meningitidis ET-15/37
Authors: KRIZ P. , KRIZ B. , SVANDOVA E. , MUSILEK M.
Published: July 2002

For many years, invasive meningococcal disease in the Czech Republic occurred sporadically
and was caused mainly by meningococci of serogroup B. In 1993, when a new clone (ET-15/37) emerged, the only phenotype found was C:2a:P1.2,5. In 1995, an antigenic variation of
the ET-15/37 clone, B:2a:P1.2,5, occurred. The results of immunological surveys conducted in
1989 and 1996 were compared. A significantly higher proportion of 1996 sera than those
collected in 1989 showed bactericidal antibodies against N. meningitidis B:2a:P1.2,5 (19·7 vs.
5·1%) and N. meningitidis C:2a:P1.2,5 (15·9 vs. 7·4%), consistent with increased herd
immunity due to the spread of the new clone in the Czech Republic. There were differences in
the age distribution of the positive sera.
A secondary school outbreak of mumps following the
childhood immunization programme in England and Wales
Authors: WEHNER H. , MORRIS R. , LOGAN M. , HUNT D. , JIN L. , STUART J. , CARTWRIGHT K.
Published: July 2002

Since the introduction of routine measles, mumps and rubella immunization for children in
England and Wales in 1988, the incidence of mumps has declined steadily. We describe an
outbreak of mumps in 1996 attacking 34 of a cohort of 98 schoolchildren born in 1982 and
1983. This is the largest outbreak in the UK since the introduction of the vaccine into the
childhood immunization schedule. Salivary IgM assay was used as a simple, minimally invasive
test to confirm the diagnosis. The occurrence of the outbreak demonstrates that British
children who were just too old to receive mumps immunization in 1988 continue to be at risk
of this disease as a result of diminished natural exposure. Further cases and outbreaks in this
cohort are to be expected. Cohorts born before 1982 appear to be at less risk, presumably
because of naturally acquired infection before the introduction of immunization.
Incidence and prognosis of tuberculosis in patients with
cirrhosis of the liver. A Danish nationwide population based study
Authors: THULSTRUP A. M. , MØLLE I. , SVENDSEN N. , SØRENSEN H. T.
Published: July 2002

We examined the incidence rate and prognosis of tuberculosis in a cohort of patients with liver
cirrhosis in Denmark. In a study cohort of 22675 patients with liver cirrhosis, we identified 151
cases of tuberculosis from 1977 to 1993. The incidence rate was 168·6 per 100000 person-years
of risk, and the highest incidence rate was among men above 65 years of age, with an
incidence rate of 246·0 per 100000 person-years of risk. The 30-day case-fatality rate was
27·3% and the 1-year case fatality rate was 47·7%. The results demonstrate that patients with
liver cirrhosis are at increased risk of tuberculosis. Additionally, it is suggested that liver
cirrhosis is an independent risk factor for tuberculosis, and that patients with liver cirrhosis
who acquire tuberculosis have a poor prognosis.
Soluble guanylate cyclase and nitric oxide synthase in synaptosomal
fractions of bovine retina
Authors: MARGULIS ALEXANDER , POZDNYAKOV NIKOLAY , DANG LOAN , SITARAMAYYA ARI
Published: July 2002

Cyclic GMP has been shown in recent years to directly
activate ion channels in bipolar and ganglion cells, and
to indirectly regulate coupling between horizontal cells,
and between bipolar and amacrine cells. In all of these
cases, the effects of cyclic GMP are mimicked by nitric
oxide. An increase in calcium concentration stimulates
the production of nitric oxide by neuronal and endothelial
forms of nitric oxide synthase, which in turn activates
soluble guanylate cyclases, enhancing the synthesis of
cyclic GMP. Though some effects of nitric oxide do not
involve cyclic GMP, the nitric oxide-cyclic GMP cascade
is well recognized as a signaling mechanism in brain and
other tissues. The widespread occurrence of nitric oxide/cyclic
GMP-regulated ion channel activity in retinal neurons raises
the possibility that nitric-oxide-sensitive soluble guanylate
cyclases play an important role in cell–cell communication,
and possibly, synaptic transmission. Immunohistochemical
studies have indicated the presence of soluble guanylate
cyclase in retinal synaptic layers, but such studies are
not suitable for determination of the density or quantitative
subcellular distribution of the enzyme. Microanalytical
methods involving microdissection of frozen retina also
showed the presence of cyclase activity in retinal plexiform
layers but these methods did not permit distinction between
nitric oxide-sensitive and insensitive cyclases. In this
study, we fractionated retinal homogenate into the cytosolic
and synaptosomal fractions and investigated the specific
activity and distribution of soluble guanylate cyclase
and nitric oxide synthase. The results show that both enzymes
are present in the synaptosomal fractions derived from
inner and outer plexiform layers. The synaptosomal fraction
derived from inner retina was highly enriched in cyclase
activity. Nitric oxide synthase activity was also higher
in the inner than outer retinal synaptosomal fraction.
The results suggest that the nitric oxide-cyclic GMP system
is operational in both synaptic layers of retina and that
it may play a more significant role in the inner retina.
Phylogenetic significance of the morphology of the cuticular scales of the lynx spiders (Araneae: Oxyopidae)
Authors: Townsend Victor R. , Felgenhauer Bruce E.
Published: July 2002

In spiders, cuticular scales are flattened, hollow setae that occur in a variety of shapes and colours. Using transmission electron microscopy and scanning electron microscopy, we examine and provide descriptions of the external and internal anatomy of prosomal and opisthosomal scales of 70 species of lynx spiders (Araneae, Oxyopidae), representing the genera Hamataliwa, Hostus, Oxyopes, Peucetia, Schaenicoscelis, Tapinillus, and Tapponia. The cuticular scales of these taxa exhibit regional (with respect to location on the body), sexual, inter‐ and intrageneric variation in external and internal morphology. In the genera, Peucetia, Schaenicoscelis, and Tapinillus, cuticular scales are plumose and only occur on the prosoma. Species of the genera Hamataliwa and Tapponia, have lanceolate scales that occur on the prosoma, legs, and opisthosoma. Hostus has spatulate scales in these areas. In the genus Oxyopes, most species have lanceolate scales on the prosoma and spatulate scales on the legs and opisthosoma. Examinations of the genitalia of 82 species of lynx spiders, revealed a strong correlation between genitalic morphology and scale shape and distribution.
Ontogenetic changes in bone compactness in male and female Nile monitors (Varanus niloticus)
Authors: de Buffrénil Vivian , Francillon‐Vieillot Hélène
Published: July 2002

The compactness of bone tissue was measured in the shaft of the femur, tibia and fibula in 390 male and female Nile monitors Varanus niloticus from three distinct regions of Sahelian Africa. In males, bone compactness increases during ontogeny in the three bones. Conversely, in females, it tends to decrease in the femur and, to a lesser extent, the tibia, but not in the fibula. In addition to this long‐term trend, gravid females have lower femoral compactness than mature non‐gravid ones. Moreover, important differences are noticeable between local samples, indicating that the variation in bone compactness during ontogeny is a flexible or even a facultative process. Histological observations reveal the existence of an extensive remodelling by resorption and reconstruction on the walls of the marrow cavity in the femur and tibia, and the complete absence of Haversian substitution. It is concluded from these data that: (1) during ovogenesis, female Nile monitors recycle skeletal calcium through cortical resorption in certain bones, if the calcium supply from food is not enough; (2) this remodelling process is not balanced, which creates a long‐term tendency towards a deficit in reconstructive bone, and a consecutive decrease in the compactness of the skeletal elements involved. The comparative and functional aspects of these results are discussed.
Movements and location at sea of South American sea lions (Otaria flavescens)
Authors: Campagna Claudio , Werner Rodolpho , Karesh William , Marín María Rosa , Koontz Fred , Cook Robert , Koontz Charles
Published: July 2002

This study examined the foraging locations of lactating female and pre‐breeding adult male South American sea lions Otaria flavescens in the Patagonian continental shelf, south‐west Atlantic ocean. Research on females included the diving pattern, and was conducted during the 1994–98 breeding seasons in five northern and central Patagonian rookeries. Twenty females were satellite‐tracked using the Argos system and yielded 1558 locations at sea. Satellite transmitters were also deployed on two adult males tracked for a total of 94 days (n= 364 locations) before the onset of the 1999 breeding season. Foraging trips for both sexes were confined to the temperate waters of the Patagonian continental shelf although males travelled greater distances than females, and arrived close (c. 80 km) to the edge of the shelf. Females from the same rookery dispersed widely and locations at sea often overlapped. Individual differences were apparent between coastal and pelagic animals. Trips lasted a mean of 3.4 days (sd= 1.3, n= 115 trips). Mean travel distance per trip was 206 km (sd= 117 km, maximum 864 km, n= 115 trips). Females reached further distances by travelling faster rather than by extending the duration of trips. Consistent with the shallow continental shelf, 65% of 75 087 dives recorded for nine animals were in the range of 2–30 m. Males alternated periods on the coast with trips to sea lasting a mean of 5.7 days (sd= 3.0, n= 8 trips). Mean travel distance exceeded 591 km (1 sd= 301 km, n= 8 trips). Results are consistent with sex differences reported from diet studies. Locations overlap with the summer operation of shelf fisheries targeting species that are also part of the sea lion diet.
Patterns of species richness and narrow endemism of terrestrial bird species in the Afrotropical region
Authors: de Klerk Helen M. , Crowe Tim M. , Fjeldså Jon , Burgess Neil D.
Published: July 2002

Geographical patterns and peaks of species richness and narrow endemism (defined by range‐restrictedness and range‐size rarity) are described for terrestrial Afrotropical birds and subsets thereof based on residency, endemism, and taxonomy. Species richness for residents and Afrotropical endemics (species globally restricted to sub‐Saharan Africa) peaks along the mountains and adjacent lowlands of eastern and southern Africa. Isolated mountains in central and western Africa and the lowlands of the north‐eastern Congo Basin (Ituri) are highlighted to a lesser degree. Peaks of narrow endemism occur in these areas as well as in the Ethiopian Highlands (particularly for non‐passerines), Somalia (particularly for passerines), and the Angolan Escarpment. Within residents, patterns of species richness vary greatly between Afrotropical endemics (which concentrate in forests on mountains and adjacent lowlands, and the southern Brachystegia woodlands) and non‐endemic residents (which concentrate in Sudanian woodlands and the Ethiopian Highlands). Patterns of species richness of residents (species that breed in the Afrotropics) and non‐breeding migrants (non‐breeding visitors to the Afrotropics) also show notable differences. The latter concentrate in areas close to the Palaearctic, which forms their distributional range centres. Patterns of species richness and narrow endemism for Afrotropical endemics show broad‐scale coincidence within mountains or mountain–lowland complexes, particularly the Cameroon–Bamenda Highland system, East African rift system and Eastern Arc mountains. However, fine‐scale coincidence of peaks of species richness and narrow endemism within these complexes is low. Narrow endemism peaks occur in areas of topographical complexity, which may have conferred localized climatic stability over short‐, medium‐, and long‐term climatic cycles (sensu Fjeldså, 1994; Fjeldsået al., 1997), allowing these areas to act as ‘species pumps’. Species accumulate in areas of high productivity. Lack of fine‐scale coincidence of narrow endemism and species richness peaks have implications for conservation prioritization exercises.
The emergence of creole subject–verb agreement and
the licensing of null subjects
Authors: Meyerhoff Miriam
Published: July 2002

A corpus of conversational Bislama (a Melanesian
creole spoken in Vanuatu, related to Tok Pisin and Solomon
Islands Pijin) suggests that during the 20th century the
creole has developed a set of regular inflectional morphemes
on the verb that agree in person and number with the subject
of the finite clause. It is shown that, where the agreement
paradigm is referentially richest, the language is also
beginning to grammaticize a tendency towards phonetically
null subjects (pro-drop). Three possible analyses of the
Bislama verb phrase are evaluated; consistent support for
only one is found in the spoken Bislama corpus. The resulting
paradigm of subject–verb agreement (i, oli,
and Ø) is analyzed in terms of the historical development
of Bislama. It is argued that the synchronic agreement
marking reflects properties derived from (i) the lexifier
(English), (ii) the substrate languages, and (iii) universal
grammar. No one component fully accounts for the patterns
of agreement marking observed. Instead, a synthesis of
all three is required, as previously observed by, for example,
G. Sankoff (1984) and Mufwene (1996). Substrate languages
provide a model for subject agreement prefixing on the
verb; the person features associated with the lexifier
‘he’ continue to be reflected in the distribution
of Bislama i; and phonetically null subjects are
emerging as the norm where the agreement paradigm best
serves to identify the subject referent. This is consonant
with generative accounts of null subject systems. Parallels
with other languages (e.g., Italian, Franco-Provençal,
Hebrew, Finnish) are examined.
Developmental changes in cortisol secretion in normal and at-risk youth
Authors: WALKER ELAINE F. , WALDER DEBORAH J. , REYNOLDS FELICIA
Published: July 2002

Adolescence is associated with an increase in the rate of certain psychiatric symptoms, and it
is typically the developmental period when prodromal features of the major psychiatric disorders
emerge. This is especially true of schizophrenia, with the majority of patients showing a marked
postpubertal rise in schizotypal signs that predates the onset of clinical symptoms in early
adulthood. Cross-sectional studies of youth have revealed a positive correlation between age and
saliva cortisol level, suggesting a normative maturational increase in activity of the
hypothalamic–pituitary–adrenal (HPA) axis. It has been hypothesized that this
increase may trigger the expression of symptoms in vulnerable individuals. The present
longitudinal study measured cortisol secretion and its relation with symptom development in
samples of youth with schizotypal personality disorder (SPD), other personality disorders, or no
Axis II disorder. The findings indicate moderate stability in cortisol levels across a 2-year period,
with a longitudinal increase in cortisol levels over time. Cortisol levels at the first and second
assessments were correlated with the severity of SPD symptoms at follow-up. The results are
consistent with the notion that the HPA axis undergoes a postpubertal maturational process that
moderates the expression of psychiatric symptoms.
Trauma, memory, and suggestibility in children
Authors: EISEN MITCHELL L. , GOODMAN GAIL S.
Published: July 2002

In this review we examine
factors hypothesized to affect children's memory for traumatic events. Theoretical ideas on
the processing and remembering of trauma are presented and critiqued. We review research on
how psychopathology may generally influence and dissociation and posttraumatic stress disorder
may specifically influence children's memory and suggestibility. The special case of child
maltreatment is addressed as it relates to interviewing children about traumatic life experiences.
Throughout we draw on current developmental, cognitive, social, and clinical theory and
research. The review covers a controversial and exciting area of psychological inquiry.