bluuebunny/crossref_metadata_2025 huggingface dataset:
Student learning in higher instrumental education: who is responsible?
Authors: Jørgensen Harald
Published: July 2002

Who is responsible for the learning outcomes for a student in higher instrumental education? The issue of students having influence and responsibility over their instrumental learning is a complex question. Based on research, this article discusses three questions. First, the relationship between teachers and students in instrumental lessons; second, the role of the students as practitioners: how independent and responsible their practice behaviour is; third, an institution's role in students' learning. Both teachers and students work in an educational institution. The institutional responsibility for students' learning is the most neglected area of students' learning generally.
New on Paternalism and Public Policy
Authors: Leonard Thomas C. , Goldfarb Robert S. , Suranovic Steven M.
Published: July 2002

Bill New's (1999) thoughtful paper has performed the valuable service of clarifying the meaning and the policy implications of paternalism. His careful formulation delimits the domain of justified state paternalism. Having argued successfully, in our view, for a narrow ambit, New proceeds to identify situations that justify paternalism. This comment is written in the spirit of a friendly reformulation that refines and improves the specification of when paternalism is justified. Our argument is two-fold. First, we argue that New's formulation, properly understood, will not readily permit the paternalistic interventions he argues are justified. Second, we identify a class of potentially justified interventions that have paternalistic aspects, but which are neither strictly paternalistic nor market-failure remedies.
MEASURING COSTS IN COST-UTILITY ANALYSES
Authors: Stone Patricia W. , Chapman Richard H. , Sandberg Eileen A. , Liljas Bengt , Neumann Peter J.
Published: July 2002

Objectives: Although cost-utility analysis (CUA) has been
recommended by some experts as the preferred technique for economic
evaluation, there is controversy regarding what costs should be included and
how they should be measured. The purpose of this study was to: a) identify the
cost components that have been included in published CUAs; b) catalogue the
sources of valuation used; c) examine the methods employed for estimating
costs; and d) explore whether methods have changed over time.

Methods: We conducted a comprehensive search of the published
literature and systematically collected data on the cost estimation of CUAs.
We audited the cost estimates in 228 CUAs.

Results: In most studies (99%), analysts included some direct
healthcare costs. However, the inclusion of direct non-healthcare and time
costs (17%) was generally lacking, as was productivity costs (8%). Only 6% of
studies considered future costs in added life-years. In general, we found
little evidence of change in methods over time. The most frequently used
source for valuation of healthcare services was published estimates (73%). Few
studies obtained utilization data from RCTs (10%) or relied on other primary
data (23%). About two-thirds of studies conducted sensitivity analyses on cost
estimates.

Conclusions: We found wide variations in the estimation of costs
in published CUAs. The study underscores the need for more uniformity and
transparency in the field, and continued vigilance over cost estimates in CUAs
on the part of analysts, reviewers, and journal editors.
EXTRACORPOREAL SHOCK WAVE THERAPY IN ORTHOPEDICS
Authors: Wild Claudia , Khene Mahmoud , Wanke Stefan
Published: July 2002

Objective: Extracorporeal shock wave therapy (ESWT) as an emerging
technology in orthopedics has been assessed in Austria with the objective to
establish a scientific basis for pending and pressing health policy decisions.
Despite encouraging results within some indications and the promising prospect
of a noninvasive treatment for some orthopedic diseases, it seemed crucial to
assess this new field of application in the light of evidence-based standards,
without forgetting the reality of healthcare decisions. This article presents
the results of the abovementioned assessment in the context of the
policy-making process in Germany, Austria, and Switzerland.

Methods: The study is based on an overview of the already existing
reviews on the effectiveness of ESWT as carried out by different actors
(health insurances and orthopedists), and on an overview of additional
literature covering all relevant aspects (mode of action, recommendations,
economic estimates). Orthopedic societies, several institutions involved in
health technology assessment, and health insurance agencies were contacted in
search of further relevant literature, ongoing studies, and assessments.

Results: Until now, clear evidence has not been available on the
effectiveness of ESWT in four currently recommended indications (tendinosis
calcarea of the shoulder, epicondylopathia humeri radialis, calcaneal spur,
and pseudarthrosis), although a substantial body of literature has been
produced. Despite encouraging results in some indications, the lack of
coherent therapy schemes and the poor quality in the design of clinical
studies has been serious enough to hinder the drawing of reasonable
conclusions.

Conclusions: Due to the rapid diffusion of ESWT and the pressure
on reimbursement agencies to prove the ineffectiveness of ESWT, the policy
option of a pragmatic approach is recommended to controll the diffusion of an
uncertain health technology, alongside active research that would allow a more
comprehensive appraisal of this potentially interesting treatment strategy in
orthopedics.
LONG-TERM EFFECTS ON WOMEN OF ASSISTED REPRODUCTION
Authors: Shelley Julia , Venn Alison , Lumley Judith
Published: July 2002

The long-term health sequelae for women from assisted reproductive
technology (ART) have not been studied extensively. There are a number of
reasons that women's health may be compromised after ART procedures,
including the consequences of the increased incidence of multiple births,
operative deliveries, and preterm infants, the possible adverse effects of the
drug regimens used for ovarian stimulation, and the instrumentation involved
in ART procedures. In this paper we review the existing literature in these
areas. It emphasizes the effects of the drugs used for ovarian stimulation,
and in particular the incidence of cancer among women who have undergone ART.
The review indicates that there is cause for concern about the long-term
effects on women from ART treatments. It highlights the lack of research
undertaken in almost all areas related to women's long-term health after
ART. In the area of ART and cancer, it draws attention to the lack of
conclusive evidence in relation to the posited association between fertility
treatments and cancer, resulting from the limited number of very large studies
and the need for longer follow-up periods. We make a number of recommendations
regarding further research that is needed to address the current shortcomings
in the published literature.
LINEARIZATION OF RANDOMLY WEIGHTED EMPIRICALS UNDER LONG
RANGE DEPENDENCE WITH APPLICATIONS TO NONLINEAR REGRESSION
QUANTILES
Authors: Mukherjee Kanchan
Published: July 2002

This paper discusses some asymptotic uniform linearity
results of randomly weighted empirical processes based
on long range dependent random variables. These results
are subsequently used to linearize nonlinear regression
quantiles in a nonlinear regression model with long range
dependent errors, where the design variables can be either
random or nonrandom. These, in turn, yield the limiting
behavior of the nonlinear regression quantiles. As a corollary,
we obtain the limiting behavior of the least absolute deviation
estimator and the trimmed mean estimator of the parameters
of the nonlinear regression model. Some of the limiting
properties are in striking contrast with the corresponding
properties of a nonlinear regression model under independent
and identically distributed error random variables. The
paper also discusses an extension of rank score statistic
in a nonlinear regression model.
A CONSISTENT TEST FOR CONDITIONAL HETEROSKEDASTICITY IN
TIME-SERIES REGRESSION MODELS
Authors: Hsiao Cheng , Li Qi
Published: July 2002

We show that the standard consistent test for testing
the null of conditional homoskedasticity (against conditional
heteroskedasticity) can be generalized to a time-series
regression model with weakly dependent data and with generated
regressors. The test statistic is shown to have an asymptotic
normal distribution under the null hypothesis of conditional
homoskedastic error. We also discuss extension of our test
to the case of testing the null of a parametrically specified
conditional variance. We advocate using a bootstrap method
to overcome the issue of slow convergence of this test
statistic to its limiting distribution.
Evaluation of different methods to estimate understorey light conditions in tropical forests
Authors: ENGELBRECHT BETTINA M. J. , HERZ HUBERT M.
Published: July 2002

The suitability of several methods for estimating light conditions in the understorey of tropical forests,
and of different sampling schedules was evaluated. Light conditions at 16 understorey sites in a Panamanian lowland
forest were continuously measured for 9 mo with quantum sensors and photodiodes. Light conditions at the sites were
also assessed indirectly with hemispherical fisheye photographs, plant canopy analysis, 38-mm photographs, 24-mm
photographs and a spherical densiometer. Estimates from all indirect methods, except the spherical densiometer, were
highly correlated with the direct measurements. Short-term direct light measurements for a day or a week also
correlated with long-term light conditions. The indirect measures differed by up to c. 70% from the direct measures relative
to single site measurements. Hence, the indirect methods are inadequate where single site light conditions have to be
assessed accurately. However, because light conditions encountered in the understorey varied up to 13-fold, the indirect
methods were found to be well suited to rank understorey light conditions among a large number of sites. The results
from frequent and infrequent sampling schedules differed only slightly, suggesting that taking indirect measures at the
beginning and the end of a study offers a reasonable compromise between accuracy and sampling effort.
Regeneration through sprout formation in Chlorocardium rodiei (Lauraceae) in Guyana
Authors: Rijks Meta H. , Malta Erik-Jan , Zagt Roderick J.
Published: July 2002

The contribution of sprouts to the long-term survival of Chlorocardium rodiei, following logging was investigated. Differently aged sprout populations on cut stumps were surveyed to determine the numbers of sprouts produced, probability of survival and growth rates. Fifty-five to 70% of the stumps produced sprouts. The proportion of stumps that sprouted was lower for the hollow stumps than for the intact ones and the number of sprouts produced per stump was reduced. No significant correlation was found between stump diameter and the number of sprouts. Some sprouts survived for at least 15 y (usually one per stump), and these had a significantly larger average diameter relative to the sprouts at younger sites. The number of sprouts and the diameter of the largest sprout showed a significant positive correlation, suggesting that the maintenance of the inherited stump root system is shared among the sprouts so that the costs per sprout are reduced. We conclude that sprouting on cut stumps may have the potential to contribute to the maintenance of C. rodiei in the canopy at logged sites.
Effects of dung beetles (Scarabaeidae) on seeds dispersed by howler monkeys (Alouatta seniculus) in the French Guianan rain forest
Authors: Feer François
Published: July 2002

The dispersal of seeds by howler monkeys (Alouatta seniculus) and the role of dung beetles in determining the fate of the dispersed seeds were studied at Nouragues Station, French Guiana, during three 2-mo periods (April–May, 1995–97). Howler monkeys were observed to disperse seeds of 47 plant species. Monkey dung attracted 57 species of dung beetles (Scarabaeidae), including tunnellers (maximum size 37 mm) and ball rollers (12.6 mm). The rate of seed burial was negatively correlated with seed size (10 plant species) and positively correlated with dung beetle size (six species of tunnellers). More than 80% of small seeds (< 5 mm) and 30% of large seeds (22 mm), were buried by the largest tunnellers. Dung beetles buried 13 to 23% of seeds ranging 8–13 mm in width. The maximum average depth of burial was 28 cm and varied according to the species of dung beetle. The rate of disappearance of large dung clumps varied during the day and was completed by nocturnal dung beetles. Seeds of Chrysophyllum lucentifolium (Sapotaceae) buried at 5 and 10 cm depths did not suffer predation, but showed low germination success compared to seeds left at the soil surface. Dung beetles affected the survival and distribution of a portion of the seeds dispersed by monkeys, and their relative importance in shaping seed fate depended on seed and beetle size.
ON INEQUALITIES AND SELECTION OF EXPERIMENTS FOR LENGTH
BIASED DISTRIBUTIONS
Authors: Oluyede Broderick O.
Published: July 2002

The length biased distribution occurs naturally
for some sampling plans in reliability, biometry, and survival
analysis. In this note, inequalities for length biased
distributions are proved for monotone hazard functions
and mean residual life functions. The problem of sampling
and selection of experiments from the length biased distribution
as opposed to the original distribution is addressed. Certain
modified cross-entropy measures are also investigated.
THREE DIMENSIONS OF VOCABULARY DEVELOPMENT
Authors: Henriksen Birgit
Published: July 2002

Progress toward establishing a model of lexical development to guide vocabulary acquisition
research requires more precise specification of the various dimensions of lexical competence, the
interrelationships among them, and how they interface with processes of word learning and use.
Three dimensions of lexical competence are proposed: (a) partial to precise knowledge, (b) depth
of knowledge, and (c) receptive to productive use ability. The relationship between the two
knowledge dimensions and the acquisition of word meaning is considered, with emphasis on the
complexity of the semantization1 process and on the need for redefining lexical
development as both item-learning and system-changing. The adequacy of the three-dimensional
description as a reflection of the process of vocabulary development is then discussed.
Consideration of the nature of the developmental interrelationships among the dimensions raises
two further questions: (a) Is depth of knowledge a prerequisite for developing precise
comprehension? and (b) Are precise knowledge and depth of knowledge prerequisites for a word
to become productive?
THE EFFECT OF EXPOSURE FREQUENCY ON INTERMEDIATE LANGUAGE
LEARNERS' INCIDENTAL VOCABULARY ACQUISITION AND RETENTION
THROUGH READING
Authors: Rott Susanne
Published: July 2002

Research has been investigating the role of reading, as one source of input, in language
learners' vocabulary development. The present study was designed to examine whether
intermediate learners incidentally (a) acquire and (b) retain unknown vocabulary as a result of
reading. The study further assessed (c) the effect of the text variable of exposure frequency.
Learners were exposed to unfamiliar words either two, four, or six times during reading.
Vocabulary acquisition and retention measured productive and receptive knowledge gain.
Results indicated that only two encounters with unfamiliar words during reading significantly
affected learners' vocabulary growth. Moreover, two or four exposure frequencies resulted
in fairly similar word gain, but six exposures produced significantly more vocabulary knowledge.
Retention measures showed mixed results: On productive vocabulary knowledge only half of the
subjects displayed a significant rate of retention. On receptive knowledge all but one
experimental group retained vocabulary over 4 weeks.
THE ELEMENTS OF FOREIGN LANGUAGE TEACHING.Walter
Grauberg. Clevedon, UK: Multilingual Matters, 1997. Pp. xiv + 263. $95.00 cloth, $34.95
paper.
Authors: Lovik Thomas
Published: July 2002

Grauberg has undertaken the ambitious task of presenting in a relatively short book the
linguistic and pedagogical aspects of teaching French and German as foreign languages. Despite
many serious omissions, including a framework for discussing language proficiency, his
classroom observations may prove useful for future French and German teachers.
Using metaphors as modifiers: children's production
of metaphoric compounds
Authors: GOTTFRIED GAIL M.
Published: July 2002

Although much research has investigated children's
use of metaphoric
language, methodological concerns raise questions about
the conclusions, and it remains unclear whether preschoolers
can produce metaphors. These studies employed a new methodology
to test children's
ability to produce metaphors incorporated into metaphoric
compounds. In two studies, 59 children aged 2;8–4;3,
63 children aged 4;4–6;1, and
34 adults participated in elicited production tasks. In Study
1, subjects in the COMPOUND condition corrected a
puppet's incorrect compound
labels for pictures that had metaphoric resemblances to other
objects (e.g. ‘leaf-bug’ for a bug shaped like
a stick). Subjects in the NON-METAPHORIC condition
heard incorrect compounds describing pictures
without obvious metaphoric resemblance (e.g. ‘leaf-bug’
for a round black beetle). Children in the REVERSAL
condition heard compounds with
nouns reversed (e.g. ‘bug-leaf’ for the stick-bug)
to discover whether
children distinguished between the literal and metaphoric
labels. Study 2 provided an additional test of children's
metaphoric–literal distinction.
Results showed that children as young as 3;0 produced intentional,
appropriate metaphors incorporated into compound nouns when the
stimuli and puppet's labels primed recognition of
metaphoric similarity
and compound production. Moreover, children showed evidence of a
distinction between literal and metaphoric labels. The data
show that preschool children have an early ability to use
metaphoric language but
that significant developmental change occurs between the ages
of 3;0 and 5;0 as well as beyond 5;0. Additionally, metaphoric
language in preschoolers is not limited to single-word renamings.
Case and agreement in English language development
Authors: RISPOLI MATTHEW
Published: July 2002

This study examines the relationship between third person singular
(3Psg) subject pronoun case and agreement, focusing on the hypothesis
that these two grammatical subsystems develop together. This hypothesis
is broken down into two separate, empirically testable hypotheses:
(a) that correct subject case pronoun production and the
production of agreement are correlated, and (b) that at the sentence
level, correct case is dependent on the presence of agreement. Twenty-nine children between the ages of 2;6 and 4;0 were each audiotaped for
approximately two hours playing and interacting with their primary
caregivers. Transcribed production data showed that 3Psg masculine
subject pronoun case was correlated with agreement marking, whereas
3Psg feminine subject pronoun case was not. This result suggests the
influence of a retrieval factor, termed the DOUBLE-CELL EFFECT, on the her
for she pronoun case error. At the utterance level, pronoun case was
independent of the presence of agreement. Overall, the study indicates
that the relationship between case and agreement may be discernible as
a general correlation, yet indiscernible at the level of sentence production.
Archimedean actions on median pretrees
Authors: BOWDITCH BRIAN H. , CRISP JOHN
Published: July 2002

In this paper we consider group actions on generalized treelike structures (termed
‘pretrees’) defined simply in terms of betweenness relations. Using a result of Levitt,
we show that if a countable group admits an archimedean action on a median pretree,
then it admits an action by isometries on an ℝ-tree. Thus the theory of isometric
actions on ℝ-trees may be extended to a more general setting where it merges naturally
with the theory of right-orderable groups. This approach has application also
to the study of convergence group actions on continua.
Real-World Issues and Applications
for Real-Time Geographic
Information Systems (RT-GIS)
Authors: Beaubouef Theresa , Breckenridge John
Published: July 2002

Many issues related to incorporating real-time spatial information within Geographic
Information Systems (GIS) need to be investigated. It can be established that the concept of
real-time in relation to the input, analysis, display, and output of complex spatial
information depends directly on specific user applications. This dependency has been evident
throughout the Naval Research Laboratory's development of a real-time GIS for
hydrographic surveys. This paper contrasts the issues and requirements observed for this
application with those of vector moving-map displays for high-speed aeronautical
applications. It also attempts to quantify the influence of various factors and impacts
affecting real-time response to specialised applications like vector moving-map displays.
Spatial and temporal characterization of land-use in the Buffalo National River Watershed
Authors: SCOTT H.D. , UDOUJ T.H.
Published: July 2002

Today there is much concern about the potential contamination, overuse and development of scenic rivers in more or less pristine environments. The objective of this work was to quantify the spatial and temporal changes in land-use occurring in a watershed draining a nationally protected river. The Buffalo National River of Arkansas was chosen to serve as an example of how Geographic Information System (GIS) technology can rapidly assess the environmental changes that have occurred within a watershed. GIS was used to develop a spatial database of the watershed and to describe differences in land-use data from five sample years during 1965–92. Over this time span, approximately 40 000 ha of forest were lost and converted primarily to pasture. The average rate of loss of forest was 1480 ha/yr. During this same period, the average rate of gain of pasture was 1381 ha/yr. Buffer analyses showed that pasture increased at a higher percentage rate in the buffer zones surrounding the Buffalo River than in the tributaries of the Buffalo River, and a large proportion of the increase was on higher slopes. Land-use changes were dynamic with a greater area converted to pasture than area of pasture converted to forest in the watershed. The cleared forest lands were mostly near older pastures and along streams. The reforested lands tended to occur in the more isolated areas. The Buffalo River Watershed has undergone changes in land-use that may have had impact on the water quality of the region.
Generative Systems in Design
Authors: Emdanat Samir , Stiny George , Vakaló Emmanuel-George
Published: July 2002

Generative research in design investigates compact
representations that facilitate the rapid exploration of
large design spaces. It includes among other things: rule-based
systems, feature structures, and genetic algorithms. Generative
systems are being applied to a variety of design problems
from various disciplines including engineering, product
design, and architecture. The objective is to further our
understanding of the design operations and manipulations
to create systems that better support the designers'
activity.
Serological and virological evidence of non-sexual transmission of human herpesvirus type 8 (HHV8)
Authors: VITALE F. , VIVIANO E. , PERNA A. M. , BONURA F. , MAZZOLA G. , AJELLO F. , ROMANO N.
Published: July 2002

To evaluate whether or not human herpesvirus 8 (HHV8) can be transmitted through a non-sexual route a serological survey was carried out in a group of 51 catholic nuns. The
seroprevalence rate and the geometrical mean antibody titre to anti-latent HHV8 antigen were
similar in nuns and in a group of 60 women, matched by age, in the general population (27 vs.
24%; 1028 vs. 1575, respectively). Moreover, by using nested polymerase chain reaction (PCR),
HHV8 DNA sequences were detected in 7 of 16 (43·8%) saliva and peripheral blood
mononuclear cells (PBMC) from patients with classical Kaposi's sarcoma (KS) and in 3 out of
7 (42%) AIDS-KS patients. None of 5 HIV positive persons who did not have KS tested
positive for HHV8 DNA. HHV8 DNA sequences were also detected in 2 of 12 (17%) saliva
and 1 PBMC sample out of 12 healthy HHV8 positive individuals (age range: 30–80 years old).
This paper suggests that non-sexual transmission of HHV8 is operating in our geographical
setting and saliva may be a potential source of HHV8 spreading in the general population.
The relationship between therapeutic injections and high

prevalence of hepatitis C infection in Hafizabad, Pakistan
Authors: LUBY S. P. , QAMRUDDIN K. , SHAH A. A. , OMAIR A. , PAHSA O. , KHAN A. J. , McCORMICK J.B. , HOODBHOUY F. , FISHER-HOCH S.
Published: July 2002

To determine the prevalence and routes of transmission of hepatitis
C

virus (HCV) infection in

Hafizabad, Pakistan, we collected sera in 1993 from a geographically based

random sample of

residents, and in 1994 identified 15 HCV-infected individuals (cases) and

67 age and sex matched uninfected individuals (controls). Initially we
approached

504 households, and

collected serum from a randomly selected household member in 309 (64%).

Twenty persons (6·5%) had anti-HCV antibody; 31% percent had hepatitis
B core

antibodies, and 4·3% had

hepatitis B surface antigen. In the case-control study, persons who

received more therapeutic

injections (categorized as averaging 1, 2–4, 5–9 or >10

injections per year in the previous 10

years) were more likely to be infected with HCV (odds ratio 0,

1·5, 2·5 and 6·9 respectively,

P=0·008) compared to persons averaging 0 injections per

year. Efforts to limit therapeutic

injections to only those that are medically indicated and that use

sterile equipment are essential in order to prevent transmission of HCV.
Coagulase gene polymorphism of Staphylococcus aureus
isolates from dairy cattle in different geographical areas
Authors: SU C. , HERBELIN C. , FRIEZE N. , SKARDOVA O. , SORDILLO L. M.
Published: July 2002

The objectives of this study were to investigate the coagulase gene polymorphism of
Staphylococcus aureus isolates obtained from bovine mastitic milk and to determine the
resistance of predominant and rare coagulase genotypes to bovine blood neutrophil bactericidal
activities. A total of 453 isolates were collected from four countries: the Czech Republic,
France, Korea and the United States. The isolates were subtyped into 40 types by restriction
fragment length polymorphism (RFLP) of the coagulase gene. Twenty-three strains from
predominant and rare genotypes were evaluated for their ability to resist neutrophil bactericidal
activities. There were significant (P<0·01) differences in the average percent neutrophil killing
of the predominant (16·7%) and rare (39·7%) genotypes when bacteria were opsonized with
antiserum. The results indicate that the profiles of coagulase genotype differ among geographic
locations, and only a few genotypes prevail in each location. In addition, the predominant
genotypes were more resistant to neutrophil bactericidal activities than rare genotypes.
Risk factors for indigenous campylobacter infection: a Swedish case-control study
Authors: STUDAHL A. , ANDERSSON Y.
Published: July 2002

A case-control study was conducted in western Sweden (Älvsborg County). The aim of the
study was to identify any special food items or behaviours associated with an increased risk of
contracting campylobacter infection. A total of 101 cases and 198 controls were matched for
age, sex and district of residence. The following risk factors or risk behaviours were associated
with campylobacter infection: drinking unpasteurized milk (OR 3·56, 95% CI 1·46–8·94), eating
chicken (OR 2·29, 95% CI 1·29–4·23), or eating pork with bones (chops OR 2·02, 95% CI
1·17–3·64; loin of pork OR 1·83, 95% CI 1·07–3·12),
barbecuing (OR 1·98, 95% CI 1·10–4·34),
and living or working on a farm (farm OR 3·06, 95% CI 1·58–6·62, hen/chicken-breeder OR
3·32, 95% CI 1·56–6·78), daily contact with chickens or hens
(OR 11·83, 95% CI 3·41–62·03).
Effect of moonlight on the foraging behaviour of a megachiropteran bat Cynopterus sphinx
Authors: Elangovan V. , Marimuthu G.
Published: July 2002

We studied the influence of moonlight upon the foraging activity pattern of the fruit bat Cynopterus sphinx. We observed the bats when foraging on the fruits of Calophyllum inophyllum and on the leaves of Mimusops elengi and Cassia fistula for 31, 27 and 28 days, respectively at the botanical garden in the Madurai Kamaraj University campus. The number of feeding bouts was recorded every hour between 18:00 and 05:00. A feeding bout involves a bat landing on the tree and collecting a part (or whole) of the fruit or a leaf. The total number of feeding bouts was negatively correlated with per cent moonlight each night. The number of feeding bouts decreased during the waxing phases of the moon. During the period of new moon the mean number of feeding bouts was significantly higher compared to the periods of other phases. During the first quarter and the last quarter phases, feeding occurred more during the dark part of the night, especially when the bats foraged upon M. elengi and C. fistula. While cloud cover enhanced the foraging activity, lightning and thunder suppressed it. Our study indicates that moonlight influences the foraging activity of C. sphinx.
On the geographic distribution of Loxodes rex (Protozoa, Ciliophora) and other alleged endemic species of ciliates
Authors: Esteban Genoveva F. , Finlay Bland J. , Charubhun Nuntaporn , Charubhun Bawpit
Published: July 2002

There is no consensus on the question of whether or not free‐living protist species have biogeographies, with the strongest disagreement coming from advocates of the hypothesis that the extraordinary abundance of protists drives their ubiquitous dispersal. If the probability of a species being ubiquitous is a function of its absolute global abundance, then the species that are least likely to be ubiquitous are those with relatively small global populations, i.e. the largest species. Among the free‐living ciliated protozoa, a prime candidate for such an organism must be the large (∼1200 μm long), unmistakable, fragile, non‐encysting karyorelictid Loxodes rex. This ciliate was known only from fresh waters in tropical Africa and it was long considered to be a rare example of an endemic ciliate. Here it is reported that Loxodes rex is thriving in a pond in Thailand. The status of other alleged endemic ciliate species is discussed.
Female genitalia in Pityohyphantes phrygianus, a spider with a skewed sex ratio
Authors: Uhl Gabriele , Gunnarsson Bengt
Published: July 2002

The functioning of female genitalia in many arthropods, especially the site and mode of sperm storage, may have a strong impact on the pattern of sperm usage, leading to differential male fertilization success and even varying offspring sex ratios. The female genital morphology of the linyphiid spider Pityohyphantes phrygianus was investigated, as this species was shown to possess an intriguing mechanism of sex ratio determination, possibly related to genital morphology. By means of SEM and serial semi‐thin sectioning, two distinctly different spermathecae plus an additional sperm sac, equipped with several valves, were found on each side of the genital apparatus. Sperm is stored under different conditions, as one of the spermathecae exhibits large gland cells of different types that discharge their products into the spermatheca through long secretory ducts, whereas the other spermatheca is surrounded by a simpler type of gland cell. Furthermore, there are folds instead of closed ducts leading to the spermathecae, and from the spermathecae to the oviduct. The latter fertilization‐fold runs inside the copulatory chamber and enters the oviduct from the outside. The mechanisms for sex ratio bias in spiders are discussed. The occurrence of two types of spermatheca of which one is twisted, provides good evidence for the involvement of female genital morphology in sex ratio control of P. phrygianus offspring. Data are compiled on species for which information is available on sex ratio and female genital morphology. We put forward a hypothesis that in species with a skewed sex ratio, there is interaction between female genital morphology and behaviour, i.e. change of body position before, during or immediately after sperm transfer.
Body size and paternal investment in the genus Onthophagus (Coleoptera, Scarabaeoidea)
Authors: Palestrini Claudia , Rolando Antonio
Published: July 2002

During reproduction, dung beetles of the genus Onthophagus typically bury portions of dung removed from the dung pad. Even though females are capable of successfully constructing and provisioning nests when unaccompanied by males, extensive levels of co‐operation between sexes have been reported. In some species, males show a clear dimorphism in body plan and only large horned males are known to assist females. In O. taurus this form of paternal investment is facultative and depends on social context (namely the presence of other males). We studied relationships between body size and paternal investment in five Onthophagus species (i.e. O. coenobita, O. fracticornis, O. illyricus, O. taurus and O. vacca). Two types of tests were established. In test A, a large and a small male were placed with a single, medium‐size female; in test B, a large and a small female were placed with a single large male. In controls one male was placed with one female. Individuals were maintained for 10 days. Then the enclosures were opened to assess the position of each beetle. When two mates were found in close vicinity or in the same tunnel provisioning dung, a co‐operative behaviour was assumed. In competitive tests, small males and small females never co‐operated with their potential mates whilst large and medium‐size individuals often co‐operated with mates inside the same tunnels. No differences in frequencies of co‐operation were found between large and medium‐size females. Small females and small males scarcely co‐operated with large or medium‐size mates in controls. These results suggest that large individuals outcompete the small ones. They also suggest that paternal investment depends on body size of both mates. Large males of all species assist medium‐size and large females, whereas small males do not. However, large males do not invest much parental effort on small females that, in fact, are poorly assisted. We assume that large individuals of both sexes are reproductively superior to small ones. The propensity of both small females and small males to excavate was lower than that of larger individuals; accordingly, digging capacity could be a proximate factor explaining facultative paternal investment in these species.
Asymmetrical gaits of juvenile Crocodylus johnstoni, galloping Australian crocodiles
Authors: Renous S. , Gasc J.‐P. , Bels V. L. , Wicker R.
Published: July 2002

Seven juvenile individuals of the Australian species Crocodylus johnstoni from the Frankfurt Zoological Park were filmed on high‐speed video, at 250 fields s−1, whilst freely moving at various speeds in a long corridor. The sequences of locomotion were analysed to determine the various space and time parameters to characterize limb kinematics. We found that the animals use diverse patterns of asymmetrical gait, revealing great flexibility in limb co‐ordination. In all these gaits, the forelimb strikes the ground first, in the couple made by diagonally opposite fore‐ and hindlimbs. Among these gaits, rotary gallop offers probably a high level of manoeuvrability, whereas transverse gallop resulted in a higher level of stability. Speed increase is achieved by half‐bound and bound, the latter being the only gait used at velocities > 2 m s−1. Speed was increased mainly by increasing the stride length of the fore‐ and hindlimbs by simultaneously increasing both its components, the step and swing lengths. However, in bound, the step length of each forelimb increased more than the swing length, resulting in a stronger thrust action, whereas swing length increased more than step length for the hindlimb, causing the centre of mass to accelerate forwards during its ballistic phase. The asymmetrical gaits of crocodiles such as Crocodylus johnstoni are probably not functionally equivalent to the transitional asymmetrical gaits exhibited by lizards when building up into a bipedal run. These gaits are also not entirely equivalent to mammalian gaits, despite the use of vertical movements of the vertebral axis in these crocodiles, favouring an erect dynamic posture.
Internal and external forces in language change
Authors: Yang Charles D.
Published: July 2002

If every productive form of linguistic expression can be
described by some idealized human grammar, an individuals's
variable linguistic behavior (Weinreich, Labov, & Herzog,
1968) can be modeled as a statistical distribution of multiple
idealized grammars. The distribution of grammars is determined
by the interaction between the biological constraints on human
grammar and the properties of linguistic data in the environment
during the course of language acquisition. Such interaction can
be formalized precisely and quantitatively in a mathematical model
of language learning. Consequently, we model language change as
the change in grammar distribution over time, which can be related
to the statistical properties of historical linguistic data. As an
empirical test, we apply the proposed model to explain the loss of
the verb-second phenomenon in Old French and Old English based on
corpus studies of historical texts.
Prediction of externalizing behavior problems from early to middle childhood: The role of
parental socialization and emotion expression
Authors: DENHAM SUSANNE A. , WORKMAN ELIZABETH , COLE PAMELA M. , WEISSBROD CAROL , KENDZIORA KIMBERLY T. , ZAHN–WAXLER CAROLYN
Published: July 2002

Parental emotions and behaviors that contribute to continuity and change in preschool
children's externalizing problems were examined. Mothers and fathers were observed
interacting with their children, and child-rearing styles were reported. Teachers, mothers, and
children reported children's antisocial, oppositional behavior. Externalizing problems
showed strong continuity 2 and 4 years later. Proactive parenting (i.e., supportive presence, clear
instruction, and limit setting) predicted fewer behavior problems over time, after controlling for
initial problems; the converse was true for parental anger. In contrast, the hypothesized
ameliorative contribution of parents' positive emotion was not found. Parental
contributions were most influential for children whose initial problems were in the clinical range.
In particular, parental anger predicted continuation of problems over time. Paternal, as well as
maternal, influences were identified. Examination of parental emotions and inclusion of fathers is
important to research and intervention with young antisocial children.
The dynamics of drops and attached interfaces for the constrained Allen–Cahn equation
Authors: STAFFORD D. , WARD M. J. , WETTON B.
Published: July 2002

The motion of interfaces for a mass-conserving Allen–Cahn equation that are attached to the
boundary of a two-dimensional domain is studied. In the limit of thin interfaces, the interface
motion for this problem is known to be governed by an area-preserving mean curvature
flow. A numerical front-tracking method, that allows for a numerical solution of this type of
curvature flow, is used to compute the motion of interfaces that are attached orthogonally
to the boundary. Results obtained from these computations are favourably compared with
a previously-derived asymptotic result for the motion of attached interfaces that enclose a
small area. The area-preserving mean curvature flow predicts that a semi-circular interface is
stationary when it is attached to a flat segment of the boundary. For this case, the interface
motion is shown to be metastable and an explicit characterization of the metastability is
given.
On a family of differential equations for boundary layer approximations in porous media
Authors: BELHACHMI ZAKARIA , BRIGHI BERNARD , TAOUS KHALID
Published: July 2002

Free convection along a vertical flat plate embedded in a porous medium is considered,
within the framework of boundary layer approximations. In some cases, similarity solutions
can be obtained by solving a boundary value problem involving an autonomous third-order
nonlinear equation, depending on a parameter related to the temperature on the wall. The
paper deals with existence and uniqueness questions to this problem, for every value of the
parameter.
Stress-driven diffusion in a drying liquid paint layer
Authors: VAN DE FLIERT B. W. , VAN DER HOUT R.
Published: July 2002

A model is presented for the diffusion-driven drying
of a polymeric solution such as liquid
paint. Included is a stress build-up and relaxation in the polymer network
of the viscoelastic
material, which influences the diffusion process. The behaviour of the
(one-dimensional) model
is analysed by means of the maximum principle and illustrated with numerical
calculations.
On the global bifurcation diagram for the
one-dimensional Ginzburg–Landau model of superconductivity
Authors: DANCER E. N. , HASTINGS S. P.
Published: July 2002

Some new global results are given about solutions to the boundary value problem for the
Euler–Lagrange equations for the Ginzburg–Landau model of a one-dimensional superconductor.
The main advance is a proof that in some parameter range there is a branch of
asymmetric solutions connecting the branch of symmetric solutions to the normal state. Also,
simplified proofs are presented for some local bifurcation results of Bolley and Helffer. These
proofs require no detailed asymptotics for solution of the linear equations. Finally, an error
in Odeh's work on this problem is discussed.
Distributed communication in ML
Authors: HAYDEN MARK
Published: July 2002

We present our experience in implementing a group communication toolkit in Objective
Caml, a dialect of the ML family of programming languages. We compare the toolkit both
quantitatively and qualitatively to a predecessor toolkit which was implemented in C. Our
experience shows that using the high-level abstraction features of ML gives substantial
advantages. Some of these features, such as automatic memory management and message
marshalling, allowed us to concentrate on those pieces of the implementation which required
careful attention in order to achieve good performance. We conclude with a set of suggested
changes to ML implementations.
Parallel functional programming on recursively
defined data via data-parallel recursion
Authors: NISHIMURA SUSUMU , OHORI ATSUSHI
Published: July 2002

This article proposes a new language mechanism for data-parallel processing of dynamically
allocated recursively defined data. Different from the conventional array-based data-
parallelism, it allows parallel processing of general recursively defined data such as lists or
trees in a functional way. This is achieved by representing a recursively defined datum as
a system of equations, and defining new language constructs for parallel transformation
of a system of equations. By integrating them with a higher-order functional language, we
obtain a functional programming language suitable for describing data-parallel algorithms
on recursively defined data in a declarative way. The language has an ML style polymorphic
type system and a type sound operational semantics that uniformly integrates the parallel
evaluation mechanism with the semantics of a typed functional language. We also show
the intended parallel execution model behind the formal semantics, assuming an idealized
distributed memory multicomputer.
Measuring and modelling patients flows through rehabilitation and continuing care
Authors: Millard PH , O’Connor M , McClean SI
Published: July 2002

Rehabilitation stands between acute care and long-term care. As such, it is difficult to define and harder still to measure. Put simply, it is a process, an attitude of mind, a philosophy; something that patients need but acute hospitals would rather do without. This paper discusses the problems of measuring and forecasting rehabilitative activity before explaining how behavioural models of flow demonstrate the interaction between acute, rehabilitative and long-stay care. Managers, directors of social service departments, and clinicians need scientifically valid methods that enable them to measure performance and to optimize decision-making. Inherent flaws in the current methods used to measure hospital activity must be overcome if rehabilitation is to occupy its rightful place in health care management.
MOUNT BLOOMFIELD, PALAWAN, PHILIPPINES: FORESTS ON GREYWACKE AND SERPENTINIZED PERIDOTITE
Authors: PROCTOR J. , BAKER A. J. M. , VAN BALGOOY M. M. J. , BRUIJNZEEL L. A. , JONES S. H. , MADULID D. A.
Published: July 2002

The forest across a sharp boundary between greywacke and serpentinized peridotite is described from a site with seasonal rainfall on Palawan, Philippines. The forest on greywacke was of much larger stature (trees up to 26m) than that on the serpentinized peridotite (trees up to 18m). The tree (>10cm dbh) species richness was the same on both substrata with 38 species in one 0.16ha plot on each side of the boundary. There were many more individuals in the greywacke plot (149) than on the serpentinized peridotite (114). Floristically the plots were very different, with only one tree species, an unidentified Madhuca, occurring on both sides of the boundary. The soil over the greywacke was notably more acid, had lower Mg/Ca quotients, and much lower nickel concentrations than the soil over serpentinized peridotite.
VARIATION IN TREE COMMUNITY COMPOSITION AND STRUCTURE WITH CHANGES IN SOIL PROPERTIES WITHIN A FRAGMENT OF SEMIDECIDUOUS FOREST IN SOUTH-EASTERN BRAZIL
Authors: OLIVEIRA-FILHO A. T. , CURI N. , VILELA E. A. , CARVALHO D. A.
Published: July 2002

The purpose of the present study was to investigate whether variations in tree community structure and soil properties were interrelated in a fragment of semideciduous forest in Martinho Campos, south-eastern Brazil. The forest was sampled by ten plots, each of which was made up of four contiguous 15×15m quadrats (total 0.9ha). Plots were randomly distributed in the fragment with the help of grid-line coordinates. Soil samples were collected from each quadrat for chemical and textural analyses, and the soil of each quadrat was classified in conformity with the US Soil Taxonomy System. All trees with diameter at the base of the stem ≥5cm were identified and measured (circumference and height). Three soil groups were recognized: Ustifluvent, Ustropept, and Dystropept. A principal component analysis independently discriminated the soil groups in terms of their chemical and textural properties, indicating the consistency of the soil classification. Significant differences among the soil groups were also found for most soil properties. Tree community physiognomy was significantly different in Ustropept soil habitat, where trees showed more pronounced slenderness. A detrended correspondence analysis indicated that tree community structure also responded to the three soil habitats. A canonical correspondence analysis, together with Spearman's rank correlations, demonstrated that species' abundance distributions were significantly correlated with the soil properties. Differences in soil nutrient content (particularly Ca2+ and K+) and in ground water regime are apparently the leading factors determining tree species distributions within the fragment.