bluuebunny/crossref_metadata_2025 huggingface dataset:
Feeding of Centroscyllium fabricii and the influence of discards on its diet in Flemish Pass (north-west Atlantic)
Authors: Punzón Antonio , Herrera Miguel Angel
Published: July 2002

One hundred and fifty-one Centroscyllium fabricii stomachs containing food were analysed on board freezer vessels in north-west Atlantic in 1992. Three length groups were established to study variations in diet with length. The most important prey group was waste products from fish processing by the fleet and fish. Diet varied with length, smaller specimens feeding on crustaceans and molluscs, offal and fish forming the main prey in larger predators.
Intra-stadial tick-borne Thogoto virus (Orthomyxoviridae) transmission: accelerated arbovirus transmission triggered by host death
Authors: WANG H. , NUTTALL P. A.
Published: July 2002

Haematophagous insect vectors of arthropod-borne viruses (arboviruses) feed repeatedly. Consequently, they can transmit arboviruses to more than one host during the same developmental stage (intra-stadial transmission). By contrast, ixodid ticks generally feed only once at each parasitic stage (larva, nymph, and adult) and hence they have only one opportunity for tick-borne virus transmission per stadium (inter-stadial transmission). Under natural conditions, tick-infested hosts may die (from disease or other causes) before the ticks have completed their long period of engorgement. A laboratory model was used to investigate the consequences of premature host death on tick-borne virus transmission. We report intra-stadial transmission of Thogoto virus by the nymphal, male, and female ticks of Rhipicephalus appendiculatus. Tick-borne Thogoto virus infection caused viraemia and death of hamsters before the nymphal and adult ticks feeding on them had completed engorgement. The resulting partially fed ticks were allowed to continue engorgement on new, uninfected hosts (interrupted feeding). During feeding on the subsequent hosts, they transmitted the virus intra-stadially to susceptible hosts (hamsters), and to uninfected co-feeding ticks on non-susceptible hosts (guinea-pigs). Intra-stadial transmission, mediated by interrupted feeding, may help explain outbreaks of rapid and fatal tick-borne viral diseases, and the epidemiology as well as evolution of virulence, in a susceptible host population. Additionally, intra-stadial transmission provides an increased risk of tick-borne pathogen transmission to humans and domestic animals during slaughter and game hunting.
Backward masking task performance in stable, euthymic out-patients with bipolar disorder
Authors: MACQUEEN G. M. , YOUNG L. T. , GALWAY T. M. , JOFFE R. T.
Published: July 2002

Background. Several studies have suggested that visual backward masking (VBM) impairment is present in patients with bipolar disorder, but the clinical features, such as current symptoms, treatment status and past burden of illness that may contribute to the impairment have not been well described. This study examined well-characterized euthymic patients on two VBM tasks to ascertain the extent of VBM impairment in this group and the clinical correlates of this impairment.

Method. Twenty-eight euthymic patients with a DSM-IV diagnosis of bipolar disorder were matched by age, sex and IQ with 28 non-psychiatric control subjects. Both groups completed two VBM tasks; one required subjects to locate the target stimulus, one required identification of the target stimulus. Reaction times and error rates across a range of target-mask inter-stimulus intervals were assessed.

Results. Patients were significantly slower and had more errors on both VBM tasks. There was a significant relation between reaction times on the identification task and past burden of illness, particularly past number of depressions. There was no discernible impact of treatment status on reaction time or performance, including no difference in lithium-treated versus not treated subjects.

Conclusions. These results are consistent with previous reports of neuropsychological deficits in euthymic bipolar disorder patients. The potential benefit to employing tasks such as VBM is that it may provide a method for relating clinical variables such as illness burden with known neural pathways in order to elucidate better the pathophysiology leading to impaired cognitive performance in patients with bipolar disorder.
BRIEF COMMUNICATION.
Authors: BEEKMAN A. T. F. , DEEG D. J. H. , VAN LIMBEEK J. , BRAAM A. W. , DE VRIES M. Z. , VAN TILBURG W.
Published: July 2002

The Center for Epidemiologic Studies Depression scale (CES-D) has been widely used
in studies of late-life depression. Psychometric properties are generally favourable, but data on the
criterion validity of the CES-D in elderly community-based samples are lacking. In a sample of
older (55–85 years) inhabitants of the Netherlands, 487 subjects were selected to study criterion
validity of the CES-D. Using the 1-month prevalence of major depression derived from the
Diagnostic Interview Schedule (DIS) as criterion, the weighted sensitivity of the CES-D was 100%;
specificity 88%; and positive predictive value 13·2%. False positives were not more likely among
elderly with physical illness, cognitive decline or anxiety. We conclude that the criterion validity of
the CES-D for major depression was very satisfactory in this sample of older adults.
Mild mental retardation: psychosocial functioning in adulthood
Authors: MAUGHAN B. , COLLISHAW S. , PICKLES A.
Published: July 2002

Background. Evidence on the adult adaptation of individuals
with mild mental retardation (MMR)
is sparse, and knowledge of the factors associated with more and less successful
functioning in
MMR samples yet more limited.

Method. Prospective data from the National Child Development
Study were used to examine social
circumstances and psychosocial functioning in adulthood in individuals
with MMR and in a non-retarded
comparison group.

Results. For many individuals with MMR, living circumstances
and social conditions in adulthood
were poor and potential stressors high. Self-reports of psychological distress
in adulthood were
markedly elevated, but relative rates of psychiatric service use fell between
childhood and
adulthood, as reflected in attributable risks. Childhood family and social
disadvantage accounted
for some 20–30% of variations between MMR and non-retarded samples
on a range of adult
outcomes. Early social adversity also played a significant role in contributing
to variations in
functioning within the MMR sample.

Conclusions. MMR appears to be associated with substantial
continuing impairment for many
individuals.
The Criminalisation of Buying Sex: the Politics of Prostitution in Sweden
Authors: GOULD ARTHUR
Published: July 2002

While there are feminists in other countries who would like to see the
buying of sex made illegal, Sweden is indeed unique for having done so.
Sweden's popular form of radical feminism has shown itself to be highly
effective in mobilising support and creating a broad consensus on an
issue which can be very divisive. This article outlines the Swedish debate
about prostitution, to find out why legislation was passed which is barely
on the agenda in other countries. While the strength and purpose of the
women's movement was a key factor, others also played a part. The
women's movement was itself rooted in a popular movement tradition
that is particularly effective in influencing government policy. The link
between drugs and prostitution provided both a rationale and a symbolic
discourse for intervention. Fears about foreign prostitutes and liberal
practices abroad played a part. Sweden's weak liberal tradition also made
the advocacy of the liberal argument difficult.
Without LTP the learning circuit is broken
Authors: Fanselow Michael S.
Published: July 2002

Since learning emerges from a circuit mediating behavior it is
unrealistic to require LTP to be a sufficient explanation of
it; however, LTP is a necessary component of some learning
circuits. The properties of that component bear a closer formal
relationship to the acquisition of associative strength than to the
modulation of attention.
Radical empiricism is not constructive
Authors: Feldman Jerome A.
Published: July 2002

The radical empiricist theory of the Quartz & Sejnowski target article would result in a brain that could not act. The attempt to bolster this position with computational arguments is misleading and often just wrong. Fortunately, other efforts are making progress in linking neural and cognitive development.
LTP and learning: Let's stay together
Authors: Hawkins Robert D.
Published: July 2002

The hypothesis that there is a 1:1 correspondence between LTP
and learning is simplistic, and the correlation approach to testing it
is therefore too limited. The alternative hypothesis that LTP plays a
role in arousal is consistent with activity-dependent neuromodulation,
but ignores the Hebbian properties of LTP. LTP may involve both types
of mechanisms, suggesting a possible synthesis of the two
hypotheses.
From neural constructivism to children's cognitive development: Bridging the gap
Authors: Mareschal Denis , Shultz Thomas R.
Published: July 2002

Missing from Quartz & Sejnowski's (Q&S's)
unique and valuable effort to relate cognitive development to neural
constructivism is an examination of the global emergent properties of
adding new neural circuits. Such emergent properties can be studied
with computational models. Modeling with generative connectionist
networks shows that synaptogenic mechanisms can account for
progressive increases in children's representational power.
Finding out about filling-in: A guide to perceptual completion for visual science and the philosophy of perception
Authors: Pessoa Luiz , Thompson Evan , Noë Alva
Published: July 2002

In visual science the term filling-in is used in
different ways, which often leads to confusion. This target article
presents a taxonomy of perceptual completion phenomena to organize
and clarify theoretical and empirical discussion. Examples of
boundary completion (illusory contours) and featural completion
(color, brightness, motion, texture, and depth) are examined, and
single-cell studies relevant to filling-in are reviewed and assessed.
Filling-in issues must be understood in relation to theoretical issues
about neural–perceptual isomorphism and linking propositions.
Six main conclusions are drawn: (1) visual filling-in comprises a
multitude of different perceptual completion phenomena; (2) certain
forms of visual completion seem to involve spatially propagating
neural activity (neural filling-in) and so, contrary to Dennett's
(1991; 1992) recent discussion of filling-in, cannot be described as
results of the brain's “ignoring an absence” or
“jumping to a conclusion”; (3) in certain cases perceptual
completion seems to have measurable effects that depend on neural
signals representing a presence rather than ignoring an absence;
(4) neural filling-in does not imply either “analytic
isomorphism” or “Cartesian materialism,” and
thus the notion of the bridge locus – a particular neural stage
that forms the immediate substrate of perceptual experience –
is problematic and should be abandoned; (5) to reject the
representational conception of vision in favor of an
“enactive” or “animate” conception
reduces the importance of filling-in as a theoretical category in
the explanation of vision; and (6) the evaluation of perceptual
content should not be determined by “subpersonal”
considerations about internal processing, but rather by considerations
about the task of vision at the level of the animal or person
interacting with the world.
Absurd environmentalism
Authors: Detterman Douglas K. , Gabriel Lynne T. , Ruthsatz Joanne M.
Published: July 2002

The position advocated in the target article should be called
“absurd environmentalism.” Literature showing that
general intelligence is related to musical ability is not cited. Also
ignored is the heritability of musical talent. Retrospective studies
supporting practice over talent are incapable of showing differences
in talent, because subjects are self-selected on talent. Reasons for
the popularity of absurd environmentalism are discussed.
Theory of mind in nonhuman primates: A question of language?
Authors: Gray Colin , Russell Phil
Published: July 2002

Two substantive comments are made. The first is
methodological, and concerns Heyes's proposals for a critical
test for theory of mind. The second is theoretical, and concerns the
appropriateness of asking questions about theory of mind in nonhuman
primates. Although Heyes warns against the apparent simplicity of the
theory of mind hypothesis, she underplays the linguistic
implications.
Testosterone and the second sex
Authors: Foss Jeffrey
Published: July 2002

Because the reciprocal theory of Mazur & Booth dominates
the static basal model, given the evidence they present, it is worth
considering the implications for women's equality, supposing it
true. Testosterone might well give males a competitive edge, and hence
higher status, creating an inequality that mere social legislation
would be ill-suited to address. Further research on the role of
testosterone is needed.
An articulatory perspective on the locus equation
Authors: Lindblom Björn
Published: July 2002

Using an articulatory model we show that locus equations make
special use of the phonetic space of possible locus patterns. There is
nothing articulatorily inevitable about their linearity or slope-
intercept characteristics. Nonetheless, articulatory factors do play
an important role in the origin of simulated locus equations, but they
cannot, by themselves, provide complete explanations for the observed
facts. As in other domains, there is interaction between perceptual
and motor factors.
A multi-modal, emergent view of the development of syllables in early phonology
Authors: Menn Lise
Published: July 2002

A narrow focus on the jaw (or on motor generators) does not
account for individual and language-specific differences in babbling
and early speech. Furthermore, data from Yoshinaga-Itano's
laboratory support earlier findings that show glottal rather than oral
stops in deaf infants' babbling: audition is crucial for
developing normal syllables.
Practice, practice, practice – Is that all it takes?
Authors: Starkes Janet , Helsen Werner
Published: July 2002

Support for Howe et al.'s conclusion that musical talent
is largely a myth is garnered from the sport literature. One issue
germane to the nurture argument is how and when motivation to
practice is formed.
Common ground on which to approach the origins of higher cognition
Authors: Byrne Richard W. , Russon Anne E.
Published: July 2002

Imitation research has been hindered by (1) overly molecular
analyses of behaviour that ignore hierarchical structure, and (2)
attempts to disqualify observational evidence. Program-level
imitation is one of a range of cognitive skills for scheduling
efficient novel behaviour, in particular, enabling an individual
to purloin the organization of another's behaviour for its
own. To do so, the individual must perceive the underlying
hierarchical schedule of the fluid action it observes and must
understand the local functions of subroutines within the overall
goal-directed process. Action-level imitation, copying strings of
actions linearly without any such understanding, is less valuable
for acquiring complex behaviour and may often have other, social
functions. At present, we lack a mechanistic understanding of the
abilities underlying program-level imitation that make it possible for
the underlying structure of complex actions to be dissected visually
and recreated in behaviour.
Old issues and new perspectives on testosterone research
Authors: Booth Alan , Mazur Allan
Published: July 2002

This Response focuses on the strength of the testosterone (T)
dominance relationship, the circumstances under which aggression
accompanies dominance, the viability of the basal model, mediators and
moderators of the T-dominance relationship, and the research that is
needed.
A model of saccade generation based on parallel processing and competitive inhibition
Authors: Findlay John M. , Walker Robin
Published: July 2002

During active vision, the eyes continually scan the visual
environment using saccadic scanning movements. This target article
presents an information processing model for the control of these
movements, with some close parallels to established physiological
processes in the oculomotor system. Two separate pathways are concerned
with the spatial and the temporal programming of the movement. In the
temporal pathway there is spatially distributed coding and the saccade
target is selected from a “salience map.” Both pathways
descend through a hierarchy of levels, the lower ones operating
automatically. Visual onsets have automatic access to the eye control
system via the lower levels. Various centres in each pathway are
interconnected via reciprocal inhibition. The model accounts for a
number of well-established phenomena in target-elicited saccades: the
gap effect, express saccades, the remote distractor effect, and the
global effect. High-level control of the pathways in tasks such as
visual search and reading is discussed; it operates through spatial
selection and search selection, which generally combine in an automated
way. The model is examined in relation to data from patients with
unilateral neglect.
What are the functional deficits produced by hippocampal and perirhinal cortex lesions?
Authors: Mayes A. R. , van Eijk R. , Gooding P. A. , Isaac C. L. , Holdstock J. S.
Published: July 2002

A hippocampal patient is described who shows preserved item
recognition and simple recognition-based recollection but impaired
recall and associative recognition. These data and other evidence
suggest that contrary to Aggleton & Brown's target article,
Papez circuit damage impairs only complex item-item-context
recollection. A patient with perirhinal cortex damage and a delayed
global memory deficit, apparently inconsistent with A&B's
framework, is also described.
Implicit and explicit knowledge: One representational medium or many?
Authors: Hampton James A.
Published: July 2002

In Dienes & Perner's analysis, implicitly represented
knowledge differs from explicitly represented knowledge only in the
attribution of properties to specific events and to self-awareness of
the knower. This commentary questions whether implicit knowledge should
be thought of as being represented in the same conceptual vocabulary;
rather, it may involve a quite different form of representation.
Unifying cell assembly theory with observations of brain dynamics
Authors: Miller R.
Published: July 2002

Empirical evidence suggests that high frequency electrographic
activity is involved in active representation of meaningful entities
in the cortex. Theoretical work suggests that distributed cell
assemblies also represent meaningful entities. However, we are
still some way from understanding how these two are related. This
commentary also makes suggestions for further investigation of the
neural basis of language at the level of both words and sentence
planning.
Lateral interactions in the superior colliculus, not an extended fixation zone, can account for the remote distractor effect
Authors: Olivier E. , Dorris M. C. , Munoz D. P.
Published: July 2002

Recordings of neuronal activity in the monkey superior colliculus (SC) suggest that the two apparently independent effects of a visual distractor on both temporal (latency) and spatial (metrics) saccade parameters may be the result of lateral interactions between subpopulations of saccade-related neurons located at different sites on the motor map of the superior colliculus. One subpopulation is activated during the planing and initiation of a saccade; the other is activated by the appearance of a distractor. The inhibitory or facilitative nature of this interaction depends on the distance between the distractor and the target and is consistent with the complex pattern of intrinsic and commissural collicular connections.
One basic or two? A rhapsody in blue
Authors: Paramei Galina V.
Published: July 2002

The controversial status of goluboi as a basic color term is discussed. Fuzzy logic alone cannot reliably attribute basic status to goluboi. Recent linguistic studies support a single basic blue category. Psychophysical data on color-space distances and color naming are currently ambiguous in this regard.
Bilingualism and testing: A special case of bias. G. Valdes and R. Figueroa.
Norwood, NJ: Ablex, 1994. Pp. 255.
Authors: Stefanakis Evangeline Harris
Published: July 2002

Guadalupe Valdes and Richard Figueroa carefully and clearly craft an argument for why
bilingualism and testing constitute a special case of bias that continues to have serious
consequences for today's school-age minority population in the United States. This
argument could not be more timely, given the drive in the United States for standards and a
rising wave of state-mandated standardized testing programs for all students, including
bilinguals. Perhaps a summary of this book should be on the desk of every educational leader and
policymaker charged with the mandate of administering standardized tests to bilingual students
and comparing their scores with those of monolingual groups for the purpose of special
education and vocational placements.
Decreasing sequences of measurable partitions: product type, standard and prestandard
Authors: FELDMAN J. , SMORODINSKY M.
Published: July 2002

This is partly exposition, partly generalization and partly completion of some of Vershik's work towards classifying sequences of measurable partitions.
Méthode de martingales et flot géodésique sur une surface de courbure constante négative
Authors: CONZE J.-P. , LE BORGNE S.
Published: July 2002

Let ({\cal T}^1 S, m, (T^t){t \in \mathbb{R}}) be the geodesic flow on the unit tangent bundle of a surface S of negative constant curvature and finite volume. We show that every Hölder function on {\cal T}^1 S is, for the discrete time action of the geodesic flow, homologous to a martingale increment. From this representation follow the central limit theorem and its improvements, and a characterization of Hölder functions which are coboundaries in the class of measurable functions.

Soit ({\cal T}^1 S, m, (T^t)_{t \in \mathbb{R}}) le flot géodésique sur le fibré unitaire d'une surface S de courbure négative constante de volume fini. Nous montrons que toute fonction höldérienne sur {\cal T}^1 S est, pour l'action du flot géodésique à temps discret, homologue à un accroissement de martingale. Cette représentation permet d'obtenir le théorème de la limite centrale et ses extensions, et de caractériser les fonctions höldériennes qui sont des cobords dans la classe des fonctions mesurables.
Non-uniquely ergodic foliations of thin type
Authors: MARTIN REINER
Published: July 2002

We construct a minimal foliation of thin type which is
not uniquely ergodic. The notion of thin type relates to Rips'
classification of foliations on 2-complexes.
Stable and unstable manifold structures in the Hénon family
Authors: BARGE MARCY , DIAMOND BEVERLY
Published: July 2002

For parameter values $a$ where the quadratic map $f_a(x) = 1-ax^2$ has an attracting periodic point, and small values of $b$, the Hénon map $H_{a,b}(x, y) = (1 + y - ax^2, bx)$ has a periodic attractor and an attracting set that is homeomorphic with the inverse limit of $f_a|_{[1-a, 1]}$. This attracting set consists of the collection of unstable manifolds of a hyperbolic invariant set together with the attracting periodic orbit. In the case in which $f_a$ is also not renormalizable with smaller period and $b < 0$, we give a symbolic description of the collection of stable manifolds of this hyperbolic set and show that this collection is homeomorphic with the collection of unstable manifolds precisely when the attracting periodic orbit is accessible from the complement of the attracting set, a condition that can be characterized in terms of the kneading sequence of the quadratic map. As an application, we answer a question raised by Hubbard and Oberste-Vorth by proving that the basin boundaries corresponding to three distinct period five sinks in the Hénon family are non-homeomorphic.
Smooth unimodal maps in the 1990s
Authors: GRACZYK JACEK , ŚWIA¸TEK GRZEGORZ
Published: July 2002

The purpose of this paper is to survey the key ideas which have played a role in the development of the theory of smooth unimodal maps in the 1990s so as to provide a starting point for more detailed study. Most papers underlying this survey are distinguished by great technical complexity; we have therefore attempted to extract their essence and present it in a way accessible to a non-specialist. For further study we compiled a long list of original references. Another goal of this paper is to present the multi-directional process in which ideas flowed and developed, placed in a historical order.
Local biology: bodies of difference in ageing studies
Authors: KONTOS PIA C.
Published: July 2002

In this article I critically examine the biology/culture dualism in the context
of old age. Regarding the contextualisation of the interrelationship between
biology and culture, previous studies have not adequately explored the
interaction between the physiological process of ageing, the physical and
social surroundings of the body and the body's intentionality. I suggest ways
in which anthropological and feminist advances in deconstructions and
reconstructions of the body can be deployed in the study of old age. In
particular I draw upon Margaret Lock's concept of ‘local biology’. This offers
an opportunity for the development of gerontological theory that focuses upon
the interactions between the ageing body, its experience and its locality.
Tracking chemical plumes in constrained environments
Authors: Russell R. Andrew
Published: July 2002

This paper describes an on-going project to develop robotic systems for locating chemical sources in constrained environments. There is increasing interest in

applying chemical sensing to mobile robots. Locating the source of a chemical plume is seen as an important use for a chemical sensing robot. Current research tends to concentrate on

source location in open and relatively obstacle free environments. Many of the applications for this technology will be areas where airflow is constrained and deflected by obstacles such as inside buildings, mines and subway tunnels. It is this kind of situation that this project aims to address.
SYMORO+: A system for the
symbolic modelling of robots
Authors: Khalil Wisama , Creusot Denis
Published: July 2002

This paper presents the software package SYMORO+ for the automatic
symbolic modelling of robots. This package permits to generate the direct
geometric model, the inverse geometric model, the direct kinematic model, the
inverse kinematic model, the dynamic model, and the inertial parameters
identification models.

The structure of the robots can be serial, tree
structure or containing closed loops. The package runs on Sun stations and PC
computers, it has been developed under MATHEMATICA and C
language. In this paper we give an overview of the algorithms used in the
different models; the computational cost of the dynamic models of the PUMA
robot are given.
Evaluation of parametric and nonparametric nonlinear adaptive controllers
Authors: Burdet E. , Codourey A.
Published: July 2002

In this paper, nine adaptive control
algorithms are compared. The best two of them are tested
experimentally. It is shown that the Adaptive FeedForward Controller AFFC)
is well suited for learning the parameters of the dynamic
equation, even in the presence of friction and noise. The
resulting control performance is better than with measured parameters for
any trajectory in the workspace. When the task consists of
repeating the same trajectory, an adaptive look-up-table MEMory, introduced and
analyzed in this paper, is simpler to implement and results
in even better control performance.
Redundancy coordination of multiple robotic devices for welding through genetic

algorithm
Authors: Wu L. , Cui K. , Chen S. B.
Published: July 2002

In this paper

we consider the problem of coordinating multiple motion devices for

welding. We focus on the problem of coordinating a three-axis

positioning table and a six-axis manipulator. The problem is complex

as there are nine axes involved and a number of

permutations are possible which achieve the same movements of the

weld torch. The system is redundant and the robot has

singular configurations. As a result, manual programming of the robot

system is rather difficult to complete.

Our approach to the coordination

problem is based on a subdivision of tasks. The welding

table is coordinated to align the weld point surface to

be anti-parallel to the gravity direction. The six-axis robot is

constrained to move the weld torch along the weld trajectory.

Robot coordination is achieved by placing the positioning table in

a good maneuverability position, i.e. far from its singular configurations

and far from the motion limits of the six-axis arm

and the motion limits of the track. While considering multiple

criteria, including the welding orientation, a Genetic Algorithm was employed

to globally optimize six relevant redundant degrees of the multiple

robotic system for welding. The joint angles of the arm

were generated by inverse kinematics. Our method of redundancy coordination

is superior to pseudo-inverse techniques, for it is more global

and accurate.
HEALTH TECHNOLOGY ASSESSMENT IN GREECE
Authors: Liaropoulos Lycurgus , Kaitelidou Daphne
Published: July 2002

In 1983 a health reform aimed to assure universal coverage and equity in the distribution of services in Greece.

The reform implied state responsibility for the financing and delivery of services and a reduction of the

private sector. The model was a Bismarckian scheme for social insurance. However, healthcare delivery

remains fragmented and uncoordinated and the private sector is getting stronger. The dominant payment

system is fee-for-service for the private sector and administered prices and salaries for public hospitals

and social insurance funds. The many insurers have their own eligibility requirements, validation

procedures, etc. Coverage of services by social security funds, probably among the most comprehensive

in Europe, is determined more on historical and political grounds than on efficiency or cost-effectiveness.

The system is plagued by problems, including geographical inequalities, overcentralization, bureaucratic

management, poor incentives in the public sector, open-ended financing, inefficient use of hospital beds,

and lack of cost-effectiveness. There are no specific legal provisions for the control of health technology.

Technologies are introduced without standards or formal consideration of needs. There are no current

efforts to control health technology in Greece. However, health technology assessment (HTA) has gained

increasing visibility. In 1997 a law provided for a new government agency responsible for quality

control, economic evaluation of health services, and HTA. The hope is that the new law may introduce

evaluation and assessment elements into health policy formulation and assure that cost effectiveness,

quality, and appropriate use of health technology will receive more attention.
ASYMPTOTIC DISTRIBUTIONS FOR UNIT ROOT TEST STATISTICS IN
NEARLY INTEGRATED SEASONAL AUTOREGRESSIVE MODELS
Authors: Nabeya Seiji
Published: July 2002

Seasonal autoregressive models with an intercept or
linear trend are discussed. The main focus of this paper
is on the models in which the intercept or trend parameters
do not depend on the season. One of the most important
results from this study is the asymptotic distribution
for the ordinary least squares estimator of the autoregressive
parameter obtained under nearly integrated condition, and
another is the approximation to the limiting distribution
of the t-statistic under the null for testing
the unit root hypothesis.
CHI-SQUARE-TYPE DISTRIBUTIONS FOR HEAVY-TAILED VARIATES
Authors: Mittnik Stefan , Rachev Svetlozar T. , Kim Jeong-Ryeol
Published: July 2002

The distribution of sums of squared random variables
with heavy-tailed distributions is investigated. Considering
random variables in the domain of attraction of a stable
Paretian law we derive the limiting distribution as the
degrees of freedom approach infinity. The finite-degrees-of-freedom
behavior for stable Paretian variates is simulated. Response
surface techniques are employed to compactly summarize
the simulation results for a relevant range of significance
levels.
Avian predation upon lizards and frogs in a neotropical forest understorey
Authors: POULIN BRIGITTE , LEFEBVRE GAËTAN , IBÁÑEZ ROBERTO , JARAMILLO CÉSAR , HERNÁNDEZ CARLOS , STANLEY RAND A.
Published: July 2002

Although tropical forest birds are known to prey upon small lizards and
frogs, no study has documented the attributes of vertebrate-eating birds or
whether birds prey opportunistically on the different elements of the
herpetofauna within tropical communities. This study is based on a 14-mo
investigation on avian diet, supplemented with a 3-y census of frogs and a
1-y census of lizards in a humid forest of central Panama. From 91 bird
species, 1086 regurgitates were collected, in which were found 75 lizards
and 53 frogs. Over 50% of the common, primarily insectivorous bird species
preyed upon lizards or frogs, with a mean frequency of 0.26
prey/sample. These birds (22 species, nine families) foraged on various
substrates from different strata of the forest, fed on invertebrates
averaging from 3.3 to 17.2 mm in length, weighed from 11 to 195 g, and had
bill lengths that varied from 12.2 to 49.8 mm. Based on a logistic
regression analysis, intensity of foraging at army-ant swarms was the
variable that best explained the likelihood that a bird species preyed upon
lizards, leading to a classification that was 91% correct. In contrast, bill
length and body length classified correctly 88% of the frog-eating birds,
which showed a fairly constant 1:7 bill length/body length ratio (as opposed
to a mean but highly variable 1:10 ratio in other species). A multiple
regression analysis showed that seasonal variation in intensity of lizard
predation was positively related to arthropod abundance except during the
breeding season when lizard intake decreased, presumably because nesting
birds did not follow ant swarms. Intensity of frog predation correlated with
frog abundance over time, the latter being inversely related to arthropod
availability. Ninety-seven per cent of all lizards and frogs identified in
the diet samples (n = 105) were from two genera, Anolis and
Eleutherodactylus, respectively. Prey size distribution in the regurgitates
suggested an optimal prey size of 33.5 mm snout-vent length (SVL) for
lizards and 14.5 mm SVL for frogs. Birds preyed opportunistically on the
different Anolis species, but almost exclusively upon juvenile
individuals. Abundances of the different Eleutherodactylus species
correlated with their predation rates, but these frogs represented only 10%
of all the frogs observed during the censuses. The two most common local
anurans, Colostethus flotator and Bufo typhonius, were not taken by any bird
species.
LIMITS FOR CUMULATIVE INPUT PROCESSES TO QUEUES
Authors: Whitt Ward
Published: July 2002

We establish functional central limit theorems
(FCLTs) for a cumulative input process to a fluid queue
from the superposition of independent on–off sources,
where the on periods and off periods may have heavy-tailed
probability distributions. Variants of these FCLTs hold
for cumulative busy-time and idle-time processes associated
with standard queueing models. The heavy-tailed on-period
and off-period distributions can cause the limit process
to have discontinuous sample paths (e.g., to be a non-Brownian
stable process or more general Lévy process) even
though the converging processes have continuous sample
paths. Consequently, we exploit the Skorohod M1
topology on the function space D of right-continuous
functions with left limits. The limits here combined with the
previously established continuity of the reflection map in the
M1 topology imply both heavy-traffic
and non-heavy-traffic FCLTs for buffer-content processes
in stochastic fluid networks.
LIMIT THEOREMS FOR POLLING MODELS WITH INCREASING SETUPS
Authors: Olsen Tava Lennon
Published: July 2002

Multiclass single-server systems with significant
setup times (polling models) are common in industry. This
article considers asymptotics for polling models with increasing
setup times. Two types of polling model are considered,
namely (a) polling models with polling tables, exhaustive
service, and deterministic setups, and (b) cyclic exhaustive
service polling models with general setups under heavy
traffic. It is shown that as the mean setup time increases
to infinity, the scaled intervisit time for each queue
(time between service of that queue) converges in probability
to a constant. This, in turn, is shown to imply that scaled
steady-state waiting time converges in distribution to
either a uniform distribution or a simple discrete random
variable multiplied by a uniform random variable as setups
tend to infinity. These results lead to considerable insight
into the behavior of systems with setups, and conclusions
are drawn with respect to previous studies.
MORE ON USING FORCED IDLE TIME TO IMPROVE PERFORMANCE IN
POLLING MODELS
Authors: Peköz Erol A.
Published: July 2002

A recent interesting paper (Cooper, Niu, and Srinivasan
[2]) shows how for some cyclic production systems
reducing setup times can surprisingly increase work in
process. There the authors show how in these situations
the introduction of forced idle time can be used to optimize
system performance. Here we show that introducing forced
idle time at different points during the production cycle
can further improve performance in these situations and
also in situations where the suggestions from [2]
yield no improvement.
TRANSITIVITY ALTERNATIONS IN L2 ACQUISITION Toward a Modular View of
Transfer
Authors: Montrul Silvina
Published: July 2002

This experimental study on English, Spanish, and Turkish as second languages investigates
the interaction of universal principles and L1 knowledge in interlanguage grammars by focusing
on verbs that participate in the causative/inchoative alternation (such as break in
English). These verbs have the same lexico-semantic composition, but differ crosslinguistically
as to how they encode the alternation morphologically. Results of a picture judgment task show
that, as in L1 acquisition, L2 learners of Turkish, Spanish, and English with different L1s rely on
a universal mechanism when learning transitivity alternations. L1 influence plays a prominent
role in the morphological realization of the alternation. These findings suggest that UG and L1
knowledge may not affect all linguistic domains in the same way at a given stage of
development. It is proposed that transfer is subject to modularity in interlanguage grammars.
TOP-DOWN VERSUS BOTTOM-UP ANALYSES OF INTERLANGUAGE
DATA
Authors: Young Richard , Yandell Brian
Published: July 2002

We are grateful to Hidetoshi Saito for his careful and reasoned critique of the
VARBRUL procedure in his article, “Dependence and Interaction in Frequency Data
Analysis in SLA Research” (this issue). Saito reanalyzes Young's (1988, 1991)
study of -s plural variation in the English interlanguage of native speakers of Chinese.
He raises two criticisms of the statistical analyses in the original work: (a) data from all
participants were lumped together, resulting in an analysis that ignores possible variation across
participants; and (b) interaction between independent variables was not investigated, whereas
Saito finds that an interaction term contributes to a statistical model that fits the data better than
the original analysis.
Representational change in young children's
understanding of familiar verb meaning
Authors: FORBES JAMES N. , POULIN-DUBOIS DIANE
Published: July 2002

The ability to generalize verbs to new examples of previously labelled
events demonstrates an implicit understanding that verbs are representative
symbols of categories of events. The present study examined
when and how very young children generalize familiar verbs to novel
events by using the preferential looking paradigm. Overall, 24 children
aged 1;8 and 25 children aged 2;2 demonstrated their understanding of
the verbs kick and pick-up by looking significantly longer at the target
events on control trials. Additionally, children aged 1;8 with the largest
expressive vocabulary generalized the same verbs to actions with
different agents, but not to actions differing in outcome or manner of
action. In contrast, children aged 2;2 consistently extended familiar
action verbs to other actions differing in agent or manner, regardless of
the size of their expressive vocabulary. These findings were not due to
the saliency of any of the actions used and are interpreted in terms
of representational change consistent with the acquisition of lexical
learning principles.
Autonomous linguistic systems in the language
of young children
Authors: LEVY YONATA
Published: July 2002

This paper considers cross-linguistic findings
concerning the early
development of formal, arbitrary, grammatical systems in normal
hearing and deaf children and in children with congenital
brain abnormalities. The paper reviews evidence showing
an early acquisition of
grammatical forms. Such learning is typically dissociated from the
development of the relevant semantics. Form–function
correspondences were not required for the development of
morphological paradigms and
for certain aspects of formal syntax. This finding held
across all the populations studied.

It is hypothesized that the autonomous nature of these formal
paradigms accounts for their priority in learning
cross-linguistically.
Developments in early lexical comprehension: a
comparison of parental report and controlled testing
Authors: HARRIS MARGARET , CHASIN JOAN
Published: July 2002

Six children were studied from the age of 0;6 to 1;6 in order to chart
their developing comprehension vocabularies from the first to the 100th
word. Observational data were used in the first instance to identify
newly comprehended words and then controlled testing was carried out
for each word to confirm and expand the observational data. Comprehension
of words was divided into four categories – object names,
context-bound object words, action words and personal names. The
relative frequency of the different categories of word was found to
change with the size of the comprehension vocabulary as personal names
decreased in importance and both object names and action words became
increasingly more common. There was considerable variation among
the six children especially in the proportion of object names and action
words that they understood but vocabulary composition became highly
stable between 60 and 100 words.
Engineering a large sustainable world fishery
Authors: JONES IAN S. F. , YOUNG HELEN E.
Published: July 2002

Mankind is faced with three interconnected problems, those of rising population, the provision of adequate food and the increasing level of waste carbon dioxide in the atmosphere. The ocean plays an important role at present by annually providing c. 90 Mt of high protein food and absorbing about 1000 Mt of carbon dioxide (CO2) from the atmosphere. By the year 2100 it is predicted by the United Nations (1992) that the world population will have more than doubled its 1990 level of 5.2 thousand million people and will approach 11.5 thousand million. Most of this population increase will occur in the developing countries.
Integrating product models with engineering analysis applications:
Two case studies
Authors: ARNOLD J. ANDREW , KUNZ JOHN C.
Published: July 2002

Current methods to develop standard Architecture,
Engineering, Construction (AEC) product models focus on
the definition of product model semantics without concurrent
and formal consideration of the engineering analyses that
such models must support, or formal consideration of the
requirements for sharing information between applications.
We present two case studies that demonstrate a service
to extract data from product models and provide inputs
to component analysis applications. The service was validated
in a proof-of-concept application called the Internet Broker
for Engineering Services (IBES) that extracts information
for component analysis from product models that are external
to the application and accessed across the Internet. IBES
was tested for two research cases. The product model for
the first case, control valve selection is based on STEP
Application Protocol 227. The product model for the second
case, control valve diagnosis, specifies additional semantics
that support the operations and maintenance (O&M) phase
of the facility life cycle. The cases offer evidence that
large standard data models can support routine analyses
for control valves. However, the amount of shared information
between the case applications is small and is largely dependent
upon the concurrence of component behaviors that are necessary
to model analysis. The IBES reference model and reasoning
to support information extraction was consistent for both
cases. This consistency suggests that it is possible to
define a general set of computational methods that integrate
project information models with external component analysis
applications across the product life cycle. We argue that
enabling a web-based link between product models and applications
requires a set of capabilities, including bi-directional
communication between separated data and analysis nodes,
query generation, data translation, and validation of data
extracted from semistandard models. We discuss the tentative
implication that minimal shared information calls into
question the assumption that large core product models
will work effectively in practice.
Usefulness of genetic typing methods to trace epidemiologically Salmonella serotype Ohio
Authors: SOTO S. M. , MARTÍNEZ N. , GUERRA B. , GONZÁLEZ-HEVIA M. A. , MENDOZA M. C.
Published: July 2002

Different genetic typing procedures were applied in an epidemiological study of Salmonella
serotype Ohio. Isolates that generated identical DNA fingerprints (HincII ribotypes, ERIC and
RAPD profiles) were clustered into the same lineage, and the addition of data from plasmid,
integron and resistance profiles was used to differentiate types. Results led to the determination
of the endemic and the emergent epidemic types at specific times, and to ascertain the clinical
and epidemiological impact of each type. In the series analysed (47 clinical isolates and 3 non-clinical
isolates) 11 lineages and 32 types were found. Two lineages were considered prevalent
and endemic, and during an epidemiological alert (Spain, 1998) a re-emergence and spread of
organisms mainly from the most frequent lineage had occurred. The combination of H-ribotype
with ERIC profile, as primary markers, and resistance profile with plasmid profile, as
secondary markers, was shown to be the most useful tool to trace epidemiologically Ohio.