bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of severe drought associated with the 1997–1998 El Niño in a tropical forest in Sarawak
Authors: Nakagawa Michiko , Tanaka Kenta , Nakashizuka Tohru , Ohkubo Tatsuhiro , Kato Tsuyoshi , Maeda Teizou , Sato Kaori , Miguchi Hideo , Nagamasu Hidetoshi , Ogino Kazuhiko , Teo Stephen , Hamid Abang Abudul , Seng Lee Hua
Published: July 2002

The impact of the unusually severe drought associated with the 1997–1998 El Niño on tropical forest dynamics in Sarawak, Malaysia was examined. Mortality during the non-drought period (1993–1997) in a core plot (1.38 ha) was 0.89 % y−1, while that during the drought period (1997–1998) in the same plot and a peripheral plot was 6.37 and 4.35 % y−1, respectively. The basal area lost in the drought interval was 3.4 times that of the annual incremental basal area in 1993–1997. Drought mortality was higher for the smaller trees, though it was less size dependent than the non-drought mortality. Dipterocarpaceae, which is the dominant family in the study plot, had a mortality 12–30 times higher in the drought than the non-drought period. There were no significant differences in mortality among the topographic types. From the results of a log-linear model (multi-factored contingency table), the death of trees was correlated with size class, indicating a change in the size-class structure of the forest. Thus, both the species composition and structure are totally affected by such an episodic drought even in a per-humid tropical forest.
The development of cause-of-death registration in the Netherlands, 1865–1955
Authors: VAN POPPEL FRANS , VAN DIJK JITSE P.
Published: July 2002

As elsewhere in Europe in the middle of the nineteenth century, general dissatisfaction among Dutch doctors with their position in society and with overall levels of public health led to an active endeavour to raise their own status and to improve the level of public hygiene.
For the most part these sanitary reformers or hygienists were inspired by the ‘Bodentheorie’ (literally ‘soil theory’) of the Munich hygienist Max von Pettenkofer, which postulated a specific relationship between chemical and biological processes in soil and air and in the human body, and by the Belgian statistician Adolphe Quetelet, according to whom statistics were an important means to social progress. The hygienists stressed the need for objective measures of health, including empirical research, standardization
of data collection, and increased dissemination of data.

Although a national system of death registration had been functioning in the Netherlands for more than thirty years, there was no national registration of causes of death. Only local registration of causes existed and these were considered insufficient and inaccurate.
Introduction: The economic and social
aspects of the family life-cycle in
traditional and modern Japan
Authors: SAITO OSAMU
Published: July 2002

Since the publication of the seminal book of essays Household and family
in past time in 1972, much research on the history of the family has
concentrated on the situation in western and eastern Europe, and relied
almost exclusively on census-type documents. It is, for example,
established that whereas mean household size was small, the mean age at
first marriage fairly high and neo-localism (the formation of an
independent household on marriage) dominant in western Europe, almost
the opposite applied in eastern Europe. Yet these findings do not preclude
the possibility of discovering regions where in statistical terms the mean
household size was not large and the proportion of complex households
not particularly high, but where the neo-local mode of household
formation was not the norm. Such a region could have a preference for
joint families (two or more married sons co-residing with their father) with
a low-fertility demographic regime, or stem families (one co-residing
married son) with that of intermediate to low fertility.

Traditional Japan is an example of just such a stem-family society.
There the household, not the individual, was perceived as the basic social
and legal unit of society. This unit was called ie and its headship, authority
and property were expected to be handed down from the father to a
particular son, enabling the household to follow alternating stages of
‘simple’, ‘multiple’ and
‘extended’ forms over the developmental cycle,
more or less in accordance with the predictions of Lutz Berkner. As
articles in the section of Laslett and Wall's Household and family on Japan
have already shown, the mean household size in eighteenth- and
nineteenth-century Japan was not higher than that in England, but the
mean age at marriage was lower than in the English population.
Moreover, household formation and succession rules under the Japanese
ie system were not compatible with the simple family mode.
Logical and uncertainty models for information access: current trends
Authors: CRESTANI FABIO , LALMAS MOUNIA
Published: July 2002

The current trends of research in information access as emerged from the 1999 Workshop on Logical and Uncertainty Models for Information Systems (LUMIS'99) are briefly reviewed in this paper. We believe that some of these issues will be central to future research on theory and applications of logical and uncertainty models for information access.
SCHEDULING OF AN INPUT-QUEUED SWITCH TO ACHIEVE MAXIMAL THROUGHPUT
Authors: Altman Eitan , Liu Zhen , Righter Rhonda
Published: July 2002

Achieving high throughput in input-queued switches has been
found to be difficult, especially when traffic is nonuniform
in the sense that different inputs have very different
cell generation rates. We show that for general arrival
processes, 100% throughput can be achieved with a simple
algorithm that is very easy to implement.

We consider a switch in which in each time slot, at most
one cell may be transmitted from each input, and at most
one cell may be received at each output. Cells that are
destined for output j arrive at input i
according to a stationary and ergodic process, and arrivals
are queued at the input. The problem is to decide which
inputs are to transmit to which outputs in each time slot
in order to maximize throughput. Necessary conditions for
stability are that the total arrival rate to each input
must be less than 1, and the total arrival rate destined
to each output must be less than 1. We propose a simple
scheduling algorithm and show that with this algorithm
the necessary conditions for stability are also sufficient.
COMPARISON OF QUEUES WITH DIFFERENT DISCRETE-TIME ARRIVAL PROCESSES
Authors: Hordijk Arie
Published: July 2002

Traveling times in a FIFO-stochastic event graph
are compared in increasing convex ordering for different
arrival processes. As a special case, a stochastic lower
bound is obtained for the sojourn time in a tandem network
of FIFO queues with a Markov arrival process. A counterexample
shows that the extended Ross conjecture is not true for
discrete-time arrival processes.
OPTIMALITY OF CONTROL LIMIT MAINTENANCE POLICIES UNDER NONSTATIONARY
DETERIORATION
Authors: Benyamini Zvi , Yechiali Uri
Published: July 2002

Control limit type policies are widely discussed in the
literature, particularly regarding the maintenance of deteriorating
systems. Previous studies deal mainly with stationary
deterioration processes, where costs and transition probabilities
depend only on the state of the system, regardless of its
cumulative age. In this paper, we consider a nonstationary
deterioration process, in which operation and maintenance
costs, as well as transition probabilities “deteriorate”
with both the system's state and its cumulative age.
We discuss conditions under which control limit policies
are optimal for such processes and compare them with those
used in the analysis of stationary models.

Two maintenance models are examined: in the first (as in
the majority of classic studies), the only maintenance
action allowed is the replacement of the system by a new
one. In this case, we show that the nonstationary results
are direct generalizations of their counterparts in stationary
models. We propose an efficient algorithm for finding the
optimal policy, utilizing its control limit form. In the
second model we also allow for repairs to better states
(without changing the age). In this case, the optimal policy
is shown to have the form of a 3-way control limit
rule. However, conditions analogous to those used
in the stationary problem do not suffice, so additional,
more restrictive ones are suggested and discussed.
AN INTRODUCTION TO CHILD LANGUAGE DEVELOPMENT. Susan
H. Foster-Cohen. London: Longman, 1999. Pp. xv + 232. £13.99 paper.
Authors: Lakshmanan Usha
Published: July 2002

This book is an excellent introduction to the field of child language development. It
demonstrates the need for both a theory of language development and reliable speech and
comprehension data in child language research. As Foster-Cohen states in the preface to the book,
the adoption of only a single approach, as opposed to a combination of different approaches, is
unlikely to lead to a productive understanding of child language acquisition. The book
successfully adopts the perspectives of both the empiricist and the rationalist traditions in its
treatment of key issues.
OPTIMALITY THEORY. René Kager. New York:
Cambridge University Press, 1999. Pp. xiii + 452. $64.95 cloth, $24.95 paper.
Authors: Dinnsen Daniel , McGarrity Laura W. , O'Connor Kathleen M.
Published: July 2002

This volume is an excellent introduction to the principles and workings of optimality theory, a
relatively new constraint-based framework. The focus is on phonology, which is where the theory
thus far has had its greatest impact. A basic understanding of phonology and earlier rule-based
derivational theories is assumed. At appropriate points, Kager distinguishes the different claims
made by optimality theory and derivational theories. The exercises and suggested readings at the
end of each chapter make the book highly suitable as a textbook. The conclusion of each chapter
also provides a good summary of the main points. In addition to conventional subject and
language indexes, a helpful index of constraints is included with page numbers for where the
constraint is defined and used.
LANGUAGE, EDUCATION AND SOCIETY IN A CHANGING WORLD.Tina Hickey and Jenny Williams (Eds.). Philadelphia: Multilingual
Matters, 1996. Pp. viii + 287. $59.00 cloth.
Authors: Jernudd Björn H.
Published: July 2002

This is a selection of papers from a conference hosted by the Irish Association for Applied
Linguistics at the Marino Institute of Education in Dublin in June 1994. In an introductory
paper, Rosamond Mitchell calls us to “defend and develop the professionalism of
language teachers” (p. 17), which Mary Ruane amplifies to counter pessimism among
language professionals arising from a feeling of a lack of control over “issues on a
wider agenda” (p. 27). On the same theme, John Edwards calls for sociopolitical
engagement with ethnic-minority-language situations (p. 34) and Helen Ó
Murchú calls for empowerment of the “lesser used language
communities” (p. 44) in a supportive response to Edwards' keynote address.
Discrete models for the category of Riemann surfaces
Authors: TILLMANN ULRIKE
Published: July 2002

We study algebraic models of the Segal category of Riemann surfaces
[11]. These are 2-categories based on the 1+1 dimensional
cobordism
category enriched by diffeomorphisms of surfaces (or isotopy classes of
such). In
particular, we show that one of these models is a symmetric strict monoidal
strict
2-category. The main technical tools are quotient constructions on 2-categories.
Dimension, measure and infinite Bernoulli convolutions
Authors: COOPER MICHAEL J. P.
Published: July 2002

For an infinite Bernoulli convolution whose support is a symmetric
Cantor-type
set, R. Kershner and A. Wintner [14] proved
that the convolution is absolutely
continuous or singular depending on whether the Lebesgue measure of the
support
is positive or zero respectively. Their proof employs the same construction
which was
developed originally by F. Hausdorff [11]
in his celebrated paper, ‘Dimension und
äusseres Mass’, where he introduced the notion of a fractional
dimension. In this
article we exploit this observation and prove a result which extends the
theorem of
Kershner and Wintner by considering Hausdorff instead of Lebesgue measure
for
the same class of infinite Bernoulli convolutions.
A foliated disk whose boundary is Morton's irreducible 4-braid
Authors: WRIGHT GRETCHEN
Published: July 2002

From the viewpoint of Birman and Menasco, a particular type of singular foliation
on a surface with boundary induces an embedding of the surface in 3-space, such
that the boundary of the surface is braided relative to the z-axis; hence the foliation
determines a conjugacy class in the braid group. Birman and Hirsch describe an
explicit algorithm to find a braid word representing this conjugacy class, given the
foliation. A braid word β ∈ Bn is said to
be irreducible if it is not conjugate to
a braid of the form bσ±1n−1,
with b ∈ Bn−1. We exhibit a foliation of a
disk and show that the corresponding braid word is an irreducible
element of B4. We give an
explicit geometric description of the embedding induced by the foliation and describe
a particularly nice form of symmetry possessed by this example.
Commutator estimates, Besov spaces and scattering problems for the
acoustic wave propagation in perturbed stratified fluids
Authors: ZHANG BO
Published: July 2002

Mourre's commutator method is used together with Besov spaces, in this paper, to
settle the question of uniqueness of solutions to the scattering problem for the
acoustic wave propagation in perturbed stratified fluids in Rn
with n [ges ] 2: The uniqueness
of solutions is established by introducing a radiation condition in the framework of
Besov spaces, and is then used to prove resolvent estimates in the Besov space setting
for the acoustic propagator in perturbed stratified fluids. These estimates are ‘sharp’
in a sense made precise in the text and are important in establishing existence of
solutions to the scattering problem.
Sweetmeats as Space of Desire
Authors: Parr Bruce
Published: July 2002

Rock ’n’ Roll Circus promotes an expectation of performance that is energetic, challenging, irreverent, and sexual. Their 1998 production in Brisbane of Sweetmeats follows the company's earlier work, such as The Dark, which established its reputation in Australia for idiosyncratic physical theatre with an acute awareness of its erotic potential and appeal. A close analysis of the construction of (sexual) desires and erotic energies in Sweetmeats illustrates how the study of sexuality is also the study of what may appear to be non-sexual. Interactions are a key to an appreciation of this form of physical theatre, whether they are between body and body, human and apparatus, sexual and non-sexual, desires and anxieties, and straight and queer. Lines of demarcation are blurred and superfluous. This analysis of Sweetmeats in performance makes use of Peta Tait's investigation of sexed bodies in physical theatre, and Elizabeth Grosz's (re)conceptualization of lesbian desire and its generation through contact between surfaces. Grosz's approach is particularly applicable to a form of theatre which relies on the energy of physical contact between performers, and between performer and apparatus. The latter is exploited effectively in Sweetmeats such that a circulation of multifarious, strange desires (and anxieties) permeates the production, in some sense ‘queering’ it.
Synchronised Low-Frequency Augmentation of GPS (SYLFA)
Authors: Roland William F.
Published: July 2002

As new technologies contribute to the expanded functionality of

Loran-C, and as concerns
for limitations in GPS and its augmentations are raised,
specific aspects of Loran-C have been
developed and applied to ameliorate those limitations. Specifically,
GPS availability is a
concern, particularly in over-land applications. This paper
discusses recent developments using
very high-precision synchronisation of Loran-C transmissions, new data
compression and
Loran-C signal modulation techniques to augment GPS accuracy,

availability and integrity over a very wide area at very low cost.
On the Effect of Plotting Performance
by the Errors of Pointing
Targets in the ARPA System
Authors: Pedersen Egil , Arai Yasuo , Sato Naoto
Published: July 2002

The content of this paper was presented at the International Maritime
Association
of the Mediterranean, 8th International Congress on Marine Technology in
Istanbul,
November 1997.

The effect of different measurement points on an acquired
target is theoretically investigated
with respect to the ARPA plotting performance. The target is described
by simple
geometrical figures and the echo is simplified. The actual measurement
position is generally
not at the centre of the target. This may cause errors in the standard
plotting results. The
characteristics of these errors are discussed from a nautical viewpoint.
The Impact of Solar Winds on
Navigation Aids
Authors: Sandford W. H.
Published: July 2002

Recent developments in remote imaging equipment carried on satellites
have given the
scientific community a vast amount of new information about the Sun and
its atmosphere.
Media coverage of the remarkable discoveries accompanied by impressive
images of the
Sun's atmosphere, and linkage to the loss of a television satellite
over the United States, have
focused public attention on the existence and effects of the Solar Wind.
This paper sets out
to illustrate the impact of the Solar Wind on radio aids to navigation,
and to look at the
possible effects on present and proposed systems.
A critique of environmental carrying capacity as a means of managing the effects of tourism development
Authors: LINDBERG KREG , MCCOOL STEPHEN F.
Published: July 2002

In their paper on environmental carrying capacity, Brown et al. (1997) describe some of the negative
impacts of tourism development and propose the carrying capacity framework for addressing
these impacts. Though we agree that these impacts should be addressed, we feel that the carrying
capacity approach is inadequate for the task in most situations. An examination of the steps that
are necessary for establishing a carrying capacity illustrates why this is the case (further discussion
is provided in Lindberg et al. 1997).
Transboundary biosphere reserves: a new framework for cooperation
Authors: FALL JULIET J.
Published: July 2002

Despite the increasing call for cooperation amongst the states parties to the 1992 Convention on Biological Diversity (UNTS 3069; see especially its Articles 5, 17, 18 and 20), the management of protected areas adjacent to political borders is rarely thought of as a common necessity for neighbouring countries. Setting up a zone dedicated to conservation is already a formidable challenge in the face of strongly competing interests for land. Bringing this about with two or more sovereign states sometimes seems a ‘gratuitous layer of complexity that spells almost certain failure’ (Westing 1998b). Nevertheless, transboundary protected areas are becoming increasingly common (IUCN, unpublished 1998). In fact, no less than 136 such protected area complexes involving over 406 individual protected areas and 112 different international boundaries (Zbicz & Green 1997) have been identified around the world. If proposed areas are also included, this figure can be pushed up to 200 complexes (Brunner 1998).
The future of computers and the teaching of engineering
design
Authors: SPILLERS WILLIAM R.
Published: July 2002

I would like to begin with a list of some of the
things that are happening today in the arena of engineering
design and how it is to be taught.
A binary classifier with applications to poorly defined
engineering problems
Authors: FLOOD IAN , KARTAM NABIL
Published: July 2002

The paper proposes and evaluates a binary network
architecture and complementary training algorithm designed
for pattern classification, with applications in a variety
of engineering problems. The advantages of the system are
that it can always converge on zero error for a set of
unambiguous training patterns (if required), converges
rapidly, and circumvents the issue of how many hidden neurons
to incorporate in a network. The main benefit of the proposed
system over Hamming networks, its main counterpart, is
that it can group patterns into different classes along
any boundary. The system is shown to outperform 1) the
Hamming network for a character recognition problem where
the images are subject to both position change and noise;
and 2) a radial-Gaussian network in a truck-type classification
problem. A variant of the system, where hidden neuron thresholds
are set to zero, is shown to further improve performance
if a comprehensive set of noise-free input patterns are
available for training.
Cholera in a developing megacity; Karachi, Pakistan
Authors: SHEIKH A. , KHAN A. , MALIK T. , FISHER-HOCH S. P.
Published: July 2002

Despite rapid urbanization and increasing affluence in Karachi,
cases

of cholera are frequent.

We analysed computerized isolation data from the AKUH Clinical Microbiology

Laboratory, Karachi, from 1990–6 to examine microbiological, temporal
and

demographic trends in Vibrio

cholerae infections. During this period 888 strains of V.

cholerae (566 V. cholerae serogroup

O1, and 204 V. cholerae serogroup O139) were isolated from

specimens from 886 patients;

214/464 were adult inpatients, and 250/464 paediatric

inpatients, the remaining 422

outpatients. Isolations peaked between June and August. Overlapping

epidemics occurred in

1993 and 1994 of serogroup O1 (May to August), and serogroup O139

(August to October).

All ages and social and economic strata were affected. Forty-four percent
of

all isolates were

from children under the age of 5 years. The mean age of all patients with

serogroup O1 infections was 19·6 years (±0·9) compared
with

36·7 (±1·7) for serogroup O139 infections

(P<0·0001, t test). More than a quarter (27%)

of all serogroup O1 isolates were from babies

under 2 years of age. One patient had a serogroup O1 infection followed
by

a serogroup O139 infection 1 year later. Another patient was infected with

serogroup O1 strains 5 years apart.

Emergence of resistant strains was observed, but by 1996 serogroup O139
had

disappeared. An

aquatic organism, cholera nevertheless continues to take its toll in this

city of 11 million situated in a desert.
The use of pulsed-field gel electrophoresis to examine the
epidemiology of Bordetella bronchiseptica isolated from cats and
other species
Authors: BINNS S. H. , SPEAKMAN A. J. , DAWSON S. , BENNETT M. , GASKELL R. M. , HART C. A.
Published: July 2002

A collection (164) of isolates of Bordetella bronchiseptica

made predominantly from cats (132)
but also from dogs (15), pigs (12) and other species was examined by pulsed
field gel
electrophoresis following macrorestriction digestion with XbaI.
Each
isolate was analysed twice
and the patterns were entirely reproducible. The isolates fell into 17

different strains (>3 bands different) and within strains there were

numerous subtypes. Feline isolates fell into 12 of
the 17 strains. In general, cats housed together had similar or identical

strains and subtypes of
B. bronchiseptica. There was no difference in the PFGE patterns

of isolates made from carrier
cats and those from cats with respiratory disease. Isolates from pigs and
dogs were in general
similar to the feline isolates and there was no great evidence for
species specificity. The PFGE
pattern of feline and canine isolates were more related to whether the
animals were housed
together rather than whether they came from dogs or cats.
Transmission of calicivirus by a foodhandler in the
pre-symptomatic phase of illness
Authors: GAULIN C. , FRIGON M. , POIRIER D. , FOURNIER C.
Published: July 2002

After a Christmas party in a restaurant, 48 (68%) of the 82 guests contracted calicivirus
gastroenteritis. The epidemiological investigation showed that salad was strongly associated
with the disease episode (RR=2·43, P=0·0005). Similar symptoms occurred among other
customers who had had a meal at the same restaurant on the same evening. A foodhandler
who had only prepared salad and appetizers became sick about 30 min after the end of his
shift. He had been free of symptoms while preparing food. Few outbreak investigations have
shown calicivirus transmission by foodhandlers some hours before becoming symptomatic.
Copulation by the barnacle Tetraclita japonica under natural conditions
Authors: Murata A. , Imafuku M. , Abe N.
Published: July 2002

Moulting and copulation by the barnacle Tetraclita japonica attached to an intertidal concrete pier were observed continuously with a video camera housed in a plastic case in summer 1996 and 1997. In a total of 779 individual‐day observations, 10 individuals became sexually receptive as functional females and 14 moulted. Copulation occurred not only immediately after, but also before moulting. Duration of receptivity varied from 2 min to nearly 12 h, during which functional females accepted between two to 582 penis insertions by between one to 11 surrounding males. Each insertion time was short, ranging from 0.6 to 42 s, with a median of 2.4 s. Sex role changes were observed between two animals located close to each other, the shortest interval for which was 3.3 h. No significant size differences were detected between functional males and females. A temporal pattern of copulation, with a high frequency of penis insertions of short durations, is discussed in relation to natural habitat conditions.
Two new species of Geoplanidae (Platyhelminthes, Tricladida, Terricola) of south Brazil
Authors: Leal‐Zanchet Ana Maria , Carbayo Fernando
Published: July 2002

Two new species of terrestrial planarians in the family Geoplanidae, Geoplana franciscana and Notogynaphallia guaiana, from the State of Rio Grande do Sul, Brazil, are described. Both species have a multilayered lining in the female atrium. The study of specimens of N. goetschi, aimed at comparing it to N. guaiana, reveals the need for a re‐description and review of N. goetschi.
Could the indirect competition hypothesis explain inter‐sexual site segregation in red deer (Cervus elaphus L.)?
Authors: Conradt L. , Gordon I. J. , Clutton‐Brock T. H. , Thomson D. , Guinness F. E.
Published: July 2002

Inter‐sexual segregation between habitats or between sites within a habitat is very widespread in sexually dimorphic ungulates. As an explanation, it has been suggested that males, because of their larger forage requirements, are driven from preferred, high quality forage habitats into marginal habitats of lower forage quality but higher forage biomass by female competition (‘indirect competition hypothesis’). However, this hypothesis has hardly been tested. In the present study, we tested the indirect competition hypothesis for site segregation of red deer on the Isle of Rum, Scotland, within two vegetation communities: short Agrostis/Festuca grassland and Calluna heath. We predicted that: (1) males should choose sites within each vegetation community that are of higher forage biomass but lower forage quality, than sites selected by females; (2) the degree of inter‐sexual site segregation should be highest within the vegetation community in which indirect competition was most intense. We found that the sexes were significantly segregated between sites within both vegetation communities, but males did not use sites of lower forage quality or of higher forage biomass than did females. Moreover, degree of site segregation was not significantly higher in the vegetation community in which competition was more intense (i.e. short Agrostis/Festuca grassland). We conclude that the indirect competition hypothesis cannot explain site segregation in red deer on the Isle of Rum.
Swimming speed and foraging strategies of New Zealand sea lions (Phocarctos hookeri)
Authors: Crocker D. E. , Gales N. J. , Costa D. P.
Published: July 2002

Lactating New Zealand sea lions (Phocarctos hookeri) have recently been reported to be the longest and deepest‐diving otariid. An unusually large proportion of dives exceeded a theoretical aerobic dive limit, predicted from estimated oxygen stores and measurements of diving metabolic rate. We investigated swimming speed, a key variable in both the management of oxygen stores and foraging strategies, and its relation to diving behaviour in New Zealand sea lions. Diving behaviour was nearly continuous with short inter‐dive intervals. Mean diving swimming speeds ranged from 1.6 to 2.4 m/s. Mean surface swimming speeds ranged from 0.9 to 1.8 m/s and were significantly lower than diving speeds in all subjects. New Zealand sea lions spend significant but variable amounts of time resting at the surface. Diving and swimming speed patterns were consistent with foraging on the benthos. Time in the foraging zone was maintained in deeper dives by increasing dive duration. This increased duration cannot be accounted for by a decreased metabolic rate resulting from slower swimming speeds, as speeds increased with the maximum depth of dives. Patterns of swimming speed and acceleration suggest the use of a gliding phase during descent. For most females, the extended duration of deeper dives did not impact on surface times, suggesting the use of aerobic metabolism. Females exhibited significantly slower swim speeds during the bottom segments of foraging dives than during descent or ascent. These findings suggest that swimming behaviour should be considered a critical component when modelling energetic costs for diving animals.
Professor A. J. E. Cave 1900–2001
Authors: Walls Eldred
Published: July 2002

Few have served the Zoological Society of London longer or more faithfully than Alexander Cave who died on 17 May at the great age of 100.

As a Fellow, his record is outstanding: Member of Council, Vice President, Silver Medallist of the Society, Honorary Research Associate; and withal, an unending stream of original papers on various aspects of comparative anatomy. Unending? Well, almost, for he was still being published in his 95th year. Nor should be forgotten the great volume of work that he did in refereeing papers for the Journal of Zoology– an onerous and time‐consuming task that he dealt with meticulously.
Carapace dentition patterns, morphometrics and allozyme differentiation amongst two toothed freshwater crab species (Potamonautes warreni and P. unispinus) (Decapoda: Brachyura: Potamonautidae) from river systems in South Africa
Authors: Daniels Savel R. , Stewart Barbara A. , Ridgway Tyrone M. , Florence Wayne
Published: July 2002

The taxonomic relationship between two toothed South African river crabs, Potamonautes warreni and P. unispinus, is unclear. The problem stems from the widespread variation in carapace dentition patterns amongst P. warreni individuals over its biogeographic range, where single toothed individuals may appear similar in carapace morphology to P. unispinus. Ten populations of P. warreni and 18 populations of P. unispinus were collected and the morphometric and genetic differentiation between the two taxa quantified. Patterns of morphometric and genetic variation were examined using multivariate statistics and protein gel electrophoresis, respectively. Principal component analyses of carapace characters showed that the two species are morphologically indistinguishable. However, discriminate functions analyses and additional statistical results corroborate the morphological distinction between the two taxa. Allozyme electrophoresis of 17 protein coding loci, indicated a close genetic similarity between the two species (I = 0.92). A fixed allelic difference at one locus (LT‐2) and extensive genetic variability at another locus (PGM‐1) indicate that two gene pools are present and that the two taxa are genetically isolated. Intraspecific genetic I values for both species were >0.97 and indicated no apparent genetic structuring on a micro or macro‐geographic scale. The variation in carapace dentition among P. warreni populations possesses no genetic basis and may possibly be the product of ecogenesis. The value of dentition patterns in the systematics of river crabs is discussed. Dentition patterns among river crab species appear to be conserved and reliable as species specific diagnostic markers, but should ideally be used in combination with other morphological data sets and genetic evidence.
Form and function of the selenodont molar in southern African ruminants in relation to their feeding habits
Authors: Archer Debbie , Sanson Gordon
Published: July 2002

The general aim of the present study was to test whether there are differences in the occlusal design of the ruminant selenodont molar, and by examining correlations between tooth form and diet, improve our understanding of the function of the selenodont molar within the Bovidae. Twenty‐six species of bovid ruminants were grouped into the three feeding types established by Hofmann (1968) – i.e. browsers, grazers and intermediate feeders. The characteristics of the shape, number, width and length of the enamel ridges were found to correlate with the hypothesized function of the molar occlusal surface. These follow the principles applied to non‐bovid species where adaptation of the occlusal surface has been investigated in some detail. Thirteen characteristics of the occlusal surface were scored. ANOSIM results reject the null hypothesis that there are no differences in the selenodont molar occlusal surface. SIMPER results showed that all the characteristics scored contributed to the differences between groups, and crown height was not explaining the major dissimilarity between feeding groups. Differences in enamel ridge characteristics between feeding types suggest that food is being processed in essentially different ways by the browsers and grazers. Intermediate feeding species cluster within the other feeding types, depending on what the major component of the diet is. The grouping produced by the MDS, based on dental characters, closely agrees with Hofmann's classification based on gut structure.
Melt fracture revisited
Authors: GREENBERG J. M.
Published: July 2002

In a previous paper the author and Demay advanced a model to explain the melt fracture
instability observed when molten linear polymer melts are extruded in a capillary rheometer
operating under the controlled condition that the inlet flow rate was held constant. The model
postulated that the melts were a slightly compressible viscous fluid and allowed for slipping
of the melt at the wall. The novel feature of that model was the use of an empirical switch law
which governed the amount of wall slip. The model successfully accounted for the oscillatory
behavior of the exit flow rate, typically referred to as the melt fracture instability, but did not
simultaneously yield the fine scale spatial oscillations in the melt typically referred to as shark
skin. In this note, a new model is advanced which simultaneously explains the melt fracture
instability and shark skin phenomena. The model postulates that the polymer is a slightly
compressible linearly viscous fluid but assumes no-slip boundary conditions at the capillary
wall. In simple shear the shear stress τ and strain rate d are assumed to be related by
d = Fτ, where F ranges between
F2 and F1 > F2.
A strain-rate dependent yield function is introduced and this function governs whether F evolves
towards F2 or F1. This model accounts for the
empirical observation that at high shears polymers align and slide more easily than at low
shears, and explains both the melt fracture and shark skin phenomena.
Adhesion of lipid tubules in an assembly
Authors: ROSSO RICCARDO , VIRGA EPIFIANO G.
Published: July 2002

We study a unilateral equilibrium problem for the
energy functional of a lipid tubule subject
to an external field. These tubules, which constitute many biological systems,
may form
assemblies when they are brought in contact, and so made to adhere to one
another along
at interstices. The contact energy is taken to be proportional to the area
of contact through
a constant, which is called the adhesion potential.
This competes against the external field
in determining the stability of patterns with flat interstices. Though the
equilibrium problem
is highly nonlinear, we determine explicitly the stability diagram for
the adhesion between
tubules. We conclude that the higher the field, the lower the adhesion
potential needed to
make at interstices energetically favourable, though its critical value
depends also on the
surface tension of the interface between the tubules and the isotropic
fluid around them.
The distortion of a bubble in a corner flow
Authors: OZUGURLU E. , VANDEN-BROECK J.-M.
Published: July 2002

The distortion of a two-dimensional bubble (or drop) in a corner flow of an inviscid
incompressible fluid is considered. Numerical solutions are obtained by series truncation. The
results confirm and extend previous calculations.
Automatic useless-code elimination for HOT functional programs
Authors: DAMIANI FERRUCCIO , GIANNINI PAOLA
Published: July 2002

In this paper we present two type inference systems for detecting useless-code in higher-order
typed functional programs. Type inference can be performed in an efficient and complete
way, by reducing it to the solution of a system of constraints. We also give a useless-code
elimination algorithm which is based on a combined use of these type inference systems. The
main application of the technique is the optimization of programs extracted from proofs in
logical frameworks, but it could be used as well in the elimination of useless-code determined
by program transformations.
Set constraints for destructive array update optimization
Authors: WAND MITCHELL , CLINGER WILLIAM D.
Published: July 2002

Destructive array update optimization is critical for writing scientific codes in functional
languages. We present set constraints for an interprocedural update optimization that runs
in polynomial time. This is a multi-pass optimization, involving interprocedural flow analyses
for aliasing and liveness. We characterize and prove the soundness of these analyses using
small-step operational semantics. We also prove that any sound liveness analysis induces a
correct program transformation.
EQUALS – a fast parallel implementation of a lazy
language
Authors: KASER OWEN , RAMAKRISHNAN C. R. , RAMAKRISHNAN I. V. , SEKAR R. C.
Published: July 2002

This paper describes EQUALS, a fast parallel implementation of
a lazy functional language
on a commercially available shared-memory parallel machine, the Sequent Symmetry.
In contrast to previous implementations, we propagate normal form demand at
compile time as
well as run time, and detect parallelism automatically using strictness analysis.
The EQUALS
implementation indicates the effectiveness of NF-demand propagation in
identifying significant parallelism and in achieving good sequential as well
as parallel performance. Another
important difference between EQUALS and previous implementations is
the use of reference
counting for memory management, instead of mark-and-sweep or copying garbage
collection. Implementation results show that reference counting leads to very good
scalability and low
memory requirements, and offers sequential performance comparable to generational
garbage collectors. We compare the performance of EQUALS with that of other
parallel implementations (the 〈v, G〉-machine and
GAML) as well as with the performance of SML/NJ, a
sequential implementation of a strict language.
A syntactic method for finding least fixed points of

higher-order functions over finite domains
Authors: CHUANG TYNG-RUEY , GOLDBERG BENJAMIN
Published: July 2002

This paper describes a method for finding the least fixed

points of higher-order functions over

finite domains using symbolic manipulation. Fixed point finding is an

essential component

in the calculation of abstract semantics of functional programs, providing

the foundation for

program analyses based on abstract interpretation. Previous methods for

fixed point finding

have primarily used semantic approaches, which often must traverse

large portions of the

semantic domain even for simple programs. This paper provides the

theoretical framework

for a syntax-based analysis that is potentially very fast. The proposed

syntactic method is

based on an augmented simply typed lambda calculus where the symbolic representation

of each function produced in the fixed point iteration is transformed

to a syntactic normal

form. Normal forms resulting from successive iterations are then

compared syntactically to

determine their ordering in the semantic domain, and to decide whether

a fixed point has

been reached. We show the method to be sound, complete and compositional.

Examples are presented to show how this method can be used to perform strictness

analysis for higher-order

functions over non-flat domains. Our method is compositional in the

sense that the strictness

property of an expression can be easily calculated from those of its

sub-expressions. This is

contrary to most strictness analysers, where the strictness property

of an expression has to be

computed anew whenever one of its subexpressions changes. We also

compare our approach with recent developments in strictness analysis.
Implementing theorem provers in a purely functional style
Authors: HANNA KEITH
Published: July 2002

This paper discusses the principles of implementing an LCF-style proof assistant using a purely
functional metalanguage. Two approaches are described; in both, signatures are treated as
ordinary values, rather than as mutable components within an abstract datatype. The first
approach treats the object logic as a partial algebra and represents it as a partial datatype, that
is, a datatype in which the domains of the constructors are restricted by predicate functions.
This results in a compact, executable specification of the logic. The second approach uses
an abstract type to allow an efficient representation of the logic, whilst keeping the same
interface. A case study describes how these principles were put into practice in implementing
a fairly complex dependently-sorted logic.
Server side web scripting in Haskell
Authors: MEIJER ERIK
Published: July 2002

The Common Gateway Interface (CGI) for generating dynamic documents on web servers
imposes much accidental complexity on the programmer. The Haskell/CGI library documented
in this paper hides all this unpleasantness by using the common sense ‘design pattern’
of separating model and presentation. Low-level query string requests are represented by
association lists, and primitive HTTP responses are easily constructed using a set of HTML
generating combinators. The CGI programmer only needs to write a worker function that
maps an abstract request into an abstract response. A (higher-order) wrapper function then
transmutes the worker into a real low-level CGI script that deals with the exact format of
concrete requests and responses as required by the CGI standard.
A visualisation of polymorphic type checking
Authors: JUNG YANG , MICHAELSON GREG
Published: July 2002

The understanding of polymorphic typechecking and type errors is poorly supported by
contemporary functional language implementations. Here, a novel visualisation of functions
and their types is presented based on the generation of function specific icons with graphical
type representations which change dynamically as functions are applied. This visualisation
has been implemented for a Standard ML subset within a graphical environment in which
function combinations are constrained by type matching.
Malnutrition of the elderly patient in hospital: risk factors, detection and
management
Authors: Teo Yee Kiat , Wynne HA
Published: July 2002

Dietary, biochemical and anthropometric data indicate good nutritional status,
in general, in community-dwelling, healthy elderly people, at least in the USA. In
a sample of 209 men over 65 years of age without acute disease-related nutritional
risk factors, mean intake of nutrients generally met or exceeded the recommended
dietary values, with the exception of calories, although 7% of subjects consumed
inadequate amounts of thiamine, vitamin A, vitamin C and calcium. Few subjects were
extremely underweight or obese, although body fat, as assessed by skinfold thickness,
fell over the two years of evaluation. The prevalence of malnutrition in patients
with chronic disease living in the community in the UK is estimated to be around
8%, however. In this study of more than 11 000 men and women aged 18 years
or over, consultation rates in general practice and prescription rates were lowest
amongst patients with a body-mass index between 20 and 25. Hospital outpatient referral
rates were not related to nutritional status, but both hospital admission rates and
mortality were greatest in people with a body-mass index(BMI) (kg/m2) below 20, and
declined as BMI increased.
Organization of old age psychiatry services
Authors: Banerjee Sube
Published: July 2002

In the last review on this topic for this journal the focus was mainly upon service principles and an overview of variation in provision around the world. While there have been important developments and challenges within old age psychiatry in the last five years, these fundamental principles remain valid. This paper will therefore not simply present an updated version of the last but will instead concentrate on specific issues which seem to be of particular salience in the consideration of the organization and delivery of old age psychiatry services.
Tourism and recreation at seabird breeding sites in Patagonia, Argentina: current concerns and future prospects
Authors: Yorio Pablo , Frere Esteban , Gandini Patricia , Schiavini Adrián
Published: July 2002

Seabird colonies often constitute valuable tourist attractions. Different species differ in their sensitivity to human

disturbance and, although birds may habituate to visitors, inappropriate intrusions at poorly managed sites may result in

adverse effects on breeding individuals. The rapid growth of wildlife-based tourism and recreation in coastal Patagonia,

Argentina, presents opportunities for significant economic benefits but also raises concerns about the potential effects

on seabird colonies. Sixteen seabird species breed along the Patagonian coast, with Magellanic Penguin Spheniscus

magellanicus being one of the main tourist attractions. At least 27 sites where seabirds breed are currently visited by

people either through organized tourism or for recreational purposes, 19 of which are included in coastal protected

areas. The number of visitors per year varies from 50 to more than 100,000, depending on the site. Negative effects

on seabird reproduction in Patagonia are through direct destruction of nests or their contents and desertion of offspring,

particularly at locations where seabirds nest in association with or near to colonies of avian predators. Tourism and

recreation activities are growing in extent and intensity at most coastal sectors in Patagonia. Current trends in coastal

recreation activities may result in negative effects on breeding seabirds unless management guidelines are developed

and enforced. Information shows that tourism in coastal Patagonia is compatible with seabird conservation if appropriately managed. Given the rapid increase in the interest in visiting seabird colonies in Patagonia, several management

tools such as sanctuaries, the limitation of visitor numbers and both temporal and spatial zoning, need to be implemented in the short term.
[top ][top ]-closed relations and admissibility
Authors: ABADI MARTÍN
Published: July 2002

While developing a method for reasoning about programs, Pitts defined the [top ][top ]-closed
relations as an alternative to the standard admissible relations. This paper reformulates and
studies Pitts's operational concept of [top ][top ]-closure in a semantic framework. It investigates
the non-trivial connection between [top ][top ]-closure and admissibility, showing that [top ][top ]-closure is
strictly stronger than admissibility and that every [top ][top ]-closed relation corresponds to an
admissible preorder.