bluuebunny/crossref_metadata_2025 huggingface dataset:
Verbal fluency in patients with schizophrenia and affective psychoses and their first-degree relatives
Authors: GILVARRY C. M. , RUSSELL A. , JONES P. , SHAM P. , HEMSLEY D. , MURRAY R. M.
Published: July 2002

Background. Schizophrenic patients are known to have neuropsychological deficits including impaired verbal fluency, but it is not clear whether this latter deficit is: (a) a consequence of overall intellectual deficit; (b) shared with affective psychotic patients; or (c) shared by the relatives of schizophrenic patients; and (d) shared by the relatives of affective psychotic patients.

Methods. We administered Thurstone's Verbal Fluency Test to 45 schizophrenic patients and 72 of their relatives, and 30 affective psychotic patients and 53 of their relatives. Subjects were asked to generate as many words as possible beginning with the letters ‘C’ and ‘S’ and the total was taken as the dependent variable. Subjects also completed the National Adult Reading Test (NART) to provide a measure of (pre-morbid) IQ.

Results. Schizophrenic patients generated significantly fewer words than affective psychotic patients, however adjusting for NART this became non-significant. Schizophrenic (but not affective psychotic) patients generated significantly fewer words than their relatives; again adjusting for NART this became non-significant. Patients who had been exposed to obstetric complications (OC+) and those who had not (OC−) had similarly poor verbal fluency scores. Relatives of OC+ schizophrenic patients had superior verbal fluency than relatives of OC− schizophrenic patients and this remained significant after adjustment for NART.

Conclusions. The results suggest that some families transmit impairment in verbal fluency as part of a pattern of lower overall IQ. However, in other families, relatives show largely normal neuropsychological function, and the poorer verbal performance of the schizophrenic member appears to have arisen secondary to his/her exposure to OCs.
Puberty and depression: the roles of age, pubertal

status and pubertal timing
Authors: ANGOLD A. , COSTELLO E. J. , WORTHMAN C. M.
Published: July 2002

Background. Previous work has indicated that the

2[ratio ]1 female[ratio ]male sex ratio in unipolar depressive

disorders does not emerge until some time between ages 10 and 15.

Methods. Data from four annual waves of data collection from

the Great Smoky Mountains Study

(GSMS) involving children aged nine to 16 were employed.

Results. Pubertal status better predicted the emergence of

the expected sex ratio than did age. Only

after the transition to mid-puberty (Tanner Stage III and above) were

girls more likely than boys

to be depressed. The timing of this transition had no effect on

depression rates. Before Tanner Stage

III, boys had higher rates of depression than girls, and the prevalence

of depression appeared to fall

in boys at an earlier pubertal stage than that at which it began to

rise in girls. In addition, recent

transition to Tanner Stage III or higher had a transient effect in

reducing the prevalence of depression in boys.

Conclusions. The period of emergence of increased risk for

depression in adolescent girls appears to

be a relatively sharply demarcated developmental transition occurring

in mid-puberty. Previously

reported effects of the timing of puberty (which have tended to

be transient) appeared less important

in increase of risk for depression than pubertal status.
Patient treatment insistence and medication craving
in long-term low-dosage benzodiazepine prescriptions
Authors: LINDEN M. , BÄR T. , GEISELMANN B.
Published: July 2002

Background. Long-term low-dosage dependence on benzodiazepines

is traditionally explained by
withdrawal symptoms. Previous research has not given much attention
to reports that suggest that
many patients oppose stopping benzodiazepines long before withdrawal symptoms
have developed.
This study investigates the scope of and factors associated with this pre-withdrawal
treatment
insistence.

Methods. Patients receiving long-term low-dosage benzodiazepines

in primary care were asked to
take a drug-holiday of at least 3 weeks. Sociodemographic, medication,

morbidity and attitudinal
variables were assessed in addition to the GPs' perceptions of their
patients.

Results. Two-thirds of the patients rejected the drug-holiday

proposal. Patients who refused a drug-holiday were less educated and
were using a higher percentage of long-acting benzodiazepines than
patients who accepted the drug-holiday proposal. Those who refused were
seen by their GPs as
being more complaining, harder to satisfy and less co-operative.

Conclusions. These results provide evidence for drug-seeking

or craving behaviour of patients who
receive low-dosage benzodiazepine prescriptions. A major problem in benzodiazepine
withdrawal
occurs before the withdrawal programme has even begun. These data show
that benzodiazepine
low-dosage dependence should be considered a real form of dependence.
The association of sexual and physical abuse with
somatization: characteristics of patients presenting
with irritable bowel syndrome and non-epileptic
attack disorder
Authors: REILLY J. , BAKER G. A. , RHODES J. , SALMON P.
Published: July 2002

Background. Physical symptoms are commonly presented for
treatment in the absence of physical
pathology. This study tests predictions arising from the theory that childhood
sexual abuse leads
to emotional distress, illness orientation and social dysfunction as adults
and that one or more of
these effects, in turn, leads to presentation of functional (i.e. unexplained)
symptoms.

Methods. Two groups of patients with physical symptoms in the
absence of organic disease
(non-epileptic attack disorder or irritable bowel syndrome) were contrasted
with organically diseased
groups with comparable symptoms (epilepsy and Crohn's disease, respectively).

Results. Despite their contrasting clinical presentation, irritable
bowel and non-epileptic attack
groups were similar in recalling more sexual and physical abuse, as both
children and adults, than
their comparison groups. They were also similar in being more emotionally
and socially disturbed
and illness-orientated, but these putative mediating variables could not
account for the relationship
of abuse with presentation of functional symptoms.

Conclusions. Adults presenting functional neurological and
abdominal symptoms are characterized
by history of abuse. The current focus on childhood sexual abuse should
be broadened to include
sexual, and particularly physical, abuse in adulthood as well as childhood.
The intervening
processes that link abuse to somatization remain to be identified but are
unlikely to include adult
emotional and social disturbance or general illness-orientation.
Emotional suppression: can it predict cancer outcome in women with suspicious screening
mammograms?
Authors: O'DONNELL M. C. , FISHER R. , IRVINE K. , RICKARD M. , McCONAGHY N.
Published: July 2002

Background. Previous studies have implicated emotional suppression, in particular suppression of anger, in the onset and progression of breast cancer. Many of these studies used non-standardized measures and failed to control for the effects of age and/or possible knowledge of diagnosis. The present study aimed to avoid these methodological errors in investigating the relationship of emotional suppression to a diagnosis of breast cancer in a large mammography screened population.

Method. Data were collected from 1151 women with suspicious mammograms recalled
to a breast screening programme. Prior to multidisciplinary assessment women were asked to complete the Courtauld Emotional Control Scale. Imaging assessment outcome data and biopsy results were collected.

Results. Fifteen per cent of this population subsequently were diagnosed with breast cancer. There were no significant associations between a cancer outcome and emotional suppression before or after the highly significant effect of age was taken into account.

Conclusions. These results suggest that suppression of emotion may not be relevant to the development of breast cancer. Its role in the progression of existing disease requires clarification.
Obstetric complications predict treatment response in
first-episode schizophrenia
Authors: ALVIR J. M. J. , WOERNER M. G. , GUNDUZ H. , DEGREEF G. , LIEBERMAN J. A.
Published: July 2002

Background. Understanding the role of obstetric complications (OCs) in schizophrenia could
potentially shed light on the heterogeneity in the aetiology and course of schizophrenia. Many
investigators have reported an association between OCs and schizophrenia, but few have examined
the association between OCs and treatment outcome. We investigated this question in a sample of
patients studied during their first episode of schizophrenia, schizoaffective or schizophreniform
disorder.

Method. OC histories were obtained for 59 patients participating in the Hillside First Episode Study.
Cox proportional hazards regression analysis was used to estimate the effect of OCs on treatment
response during the first episode of schizophrenia.

Results. Twelve of the 59 patients (20%) had positive histories of OCs. This group exhibited lower
rates of treatment response than those with negative OC histories (hazard ratio controlling for sex
= 0·28; 95% CI = 0·13, 0·62). The positive OC group also had significantly greater lateral ventricle
volume, baseline disorganization and number of live births. The effect of OC history on treatment
response held when these three variables were controlled for.

Conclusion. A history of obstetric complications predicted poor response to treatment in the first
episode of schizophrenia. This large effect was based on a small sample of 59 patients. Thus,
replication is called for.
Relatives' expressed emotion (EE) and PTSD
treatment outcome
Authors: TARRIER N. , SOMMERFIELD C. , PILGRIM H.
Published: July 2002

Background. Expressed emotion (EE) is a measure that has been used to assess the quality of the
relationship between patient and their key relative. It has been shown to be strongly predictive of
clinical outcome in a range of psychiatric and medical disorders. This study investigated the effect
of EE on treatment outcome in chronic post-traumatic stress disorder (PTSD).

Methods. A prospective design was adopted. The key relatives of 31 PTSD patients participating
in a treatment trial comparing imaginal exposure with cognitive therapy were interviewed and rated
on EE prior to treatment allocation. The effect of EE on post-treatment clinical outcomes was
assessed.

Results. Sixteen patients (52%) had high EE and 15 (48%) low EE relatives. Patients with high EE
relatives showed lesser change scores on the main outcome variable of the trial, the total CAPS
score, and on all the secondary outcome variables than those with low EE relatives. Using different
multiple regression models the EE scales of criticism and hostility predicted just under 20% of the
outcome variance. These two scales were highly correlated and criticism marginally predicted the
greatest variance (19·7%).

Conclusions. The results highlight the importance of the quality of the patient's social environment
in influencing their response to cognitive and behavioural treatments.
NMR spectroscopy: a multifaceted approach to macromolecular structure
Authors: Ferentz Ann E. , Wagner Gerhard
Published: July 2002

1. Introduction 29

2. Landmarks in NMR of macromolecules 32

2.1 Protein structures and methods development 32

2.1.1 Sequential assignment method 32

2.1.2 Triple-resonance experiments 34

2.1.3 Structures of large proteins 36

2.2 Protein–nucleic acid complexes 37

2.3 RNA structures 38

2.4 Membrane-bound systems 39

3. NMR spectroscopy today 40

3.1 State-of-the-art structure determination 41

3.2 New methods 44

3.2.1 Residual dipolar couplings 44

3.2.2 Direct detection of hydrogen bonds 44

3.2.3 Spin labeling 45

3.2.4 Segmental labeling 46

3.3 Protein complexes 47

3.4 Mobility studies 50

3.5 Determination of time-dependent structures 52

3.6 Drug discovery 53

4. The future of NMR 54

4.1 The ease of structure determination 54

4.2 The ease of making recombinant protein 55

4.3 Post-translationally modified proteins 55

4.4 Approaches to large and/or membrane-bound proteins 56

4.5 NMR in structural genomics 56

4.6 Synergy of NMR and crystallography in protein structure determination 56

5. Conclusion 57

6. Acknowledgements 57

7. References 57

Since the publication of the first complete solution structure of a protein in 1985 (Williamson
et al. 1985), tremendous technological advances have brought nuclear magnetic resonance
spectroscopy to the forefront of structural biology. Innovations in magnet design, electronics,
pulse sequences, data analysis, and computational methods have combined to make NMR an
extremely powerful technique for studying biological macromolecules at atomic resolution
(Clore & Gronenborn, 1998). Most recently, new labeling and pulse techniques have been
developed that push the fundamental line-width limit for resolution in NMR spectroscopy,
making it possible to obtain high-field spectra with better resolution than ever before (Dötsch
& Wagner, 1998). These methods are facilitating the study of systems of ever-increasing
complexity and molecular weight.
Alternative task construals, computational escape hatches, and dual-system theories of reasoning
Authors: Ball Linden J. , Quayle Jeremy D.
Published: July 2002

Stanovich & West's dual-system represents a major development in an understanding of reasoning and rationality. Their notion of System 1 functioning as a computational escape hatch during the processing of complex tasks may deserve a more central role in explanations of reasoning performance. We describe examples of apparent escape-hatch processing from the reasoning and judgement literature.
REM sleep deprivation: The wrong paradigm leading to wrong conclusions
Authors: Born Jan , Gais Steffen
Published: July 2002

There are obvious flaws in REM sleep suppression paradigms that do not allow any conclusion to be drawn either pro or contra the REM sleep-memory hypothesis. However, less intrusive investigations of REM sleep suggest that this sleep stage or its adjunct neuroendocrine characteristics exert a facilitating influence on certain aspects of ongoing memory formation during sleep.

[Nielsen; Vertes & Eastman]
Attention is not unitary
Authors: Woodman Geoffrey F. , Vogel Edward K. , Luck Steven J.
Published: July 2002

A primary proposal of the Cowan target article is that capacity limits arise in working memory because only 4 chunks of information can be attended at one time. This implies a single, unitary attentional focus or resource; we instead propose that relatively independent attentional mech- anisms operate within different cognitive subsystems depending on the demands of the current stimuli and tasks.
In search of common foundations for cortical computation
Authors: Phillips William A. , Singer Wolf
Published: July 2002

It is worthwhile to search for forms of coding, processing,
and learning common to various cortical regions and cognitive
functions. Local cortical processors may coordinate their activity by
maximizing the transmission of information coherently related to the
context in which it occurs, thus forming synchronized population
codes. This coordination involves contextual field (CF) connections
that link processors within and between cortical regions. The effects
of CF connections are distinguished from those mediating receptive
field (RF) input; it is shown how CFs can guide both learning and
processing without becoming confused with the transmission of RF
information. Simulations explore the capabilities of networks built
from local processors with both RF and CF connections. Physiological
evidence for synchronization, CFs, and plasticity of the RF and CF
connections is described. Coordination via CFs is related to
perceptual grouping, the effects of context on contrast sensitivity,
amblyopia, implicit influences of color in achromotopsia, object and
word perception, and the discovery of distal environmental variables
and their interactions through self-organization. Cortical computation
could thus involve the flexible evaluation of relations between input
signals by locally specialized but adaptive processors whose activity
is dynamically associated and coordinated within and between regions
through specialized contextual connections.
Informal biology is a core domain, but its construction needs experience
Authors: Hatano Giyoo
Published: July 2002

Although humans are endowed with domain-specific constraints
for acquiring informal biology, its construction requires considerable
experience with living things and their cultural representations. Less
experienced adults may not know what constitutes generic species, and
young children may rely on personification rather than category-based
inference. Atran's postulate of the living-kind module that
promptly produces universal folk taxonomy does not seem
tenable.
All information processing entails computation, or, If R. A. Fisher had been a cognitive scientist . . .
Authors: Dietrich Eric , Markman Arthur B.
Published: July 2002

We argue that the dynamical and computational hypotheses
are compatible and in fact need each other: they are about different
aspects of cognition. However, only computationalism is about the
information-processing aspect. We then argue that any form of
information processing relying on matching and comparing, as
cognition does, must use discrete representations and computations
defined over them.
Dynamical models and van Gelder's dynamicism: Two different things
Authors: Eliasmith Chris
Published: July 2002

Van Gelder has presented a position that he ties closely to a
broad class of models known as dynamical models. One can support many
of his broader claims about the importance of this class (as has been
argued by connectionists for quite some time), but there are a number
of unique characteristics of his brand of dynamicism. These
characteristics engender difficulties for his view.
Filling-in does require a mechanism, and some persistent doubts
Authors: Whittle Paul
Published: July 2002

(1) In the everyday situation of seeing a uniform patch on a
variegated background, filling-in does seem to require a mechanism.
(2) Our attempts to make matches to such a patch make us appreciate
anew the elusiveness of the phenomenon.
Staying alive: Evolution, culture, and women's intrasexual aggression
Authors: Campbell Anne
Published: July 2002

Females' tendency to place a high value on protecting
their own lives enhanced their reproductive success in the environment
of evolutionary adaptation because infant survival depended more upon
maternal than on paternal care and defence. The evolved mechanism
by which the costs of aggression (and other forms of risk taking) are
weighted more heavily for females may be a lower threshold for fear in
situations which pose a direct threat of bodily injury. Females'
concern with personal survival also has implications for sex
differences in dominance hierarchies because the risks associated
with hierarchy formation in nonbonded exogamous females are not
offset by increased reproductive success. Hence among females,
disputes do not carry implications for status with them as they do
among males, but are chiefly connected with the acquisition and
defence of scarce resources. Consequently, female competition is
more likely to take the form of indirect aggression or low-level
direct combat than among males. Under patriarchy, men have held
the power to propagate images and attributions which are favourable
to the continuance of their control. Women's aggression has
been viewed as a gender-incongruent aberration or dismissed as
evidence of irrationality. These cultural interpretations have
“enhanced” evolutionarily based sex differences by
a process of imposition which stigmatises the expression of aggression
by females and causes women to offer exculpatory (rather than
justificatory) accounts of their own aggression.
Perceptual symbol systems
Authors: Barsalou Lawrence W.
Published: July 2002

Prior to the twentieth century, theories of knowledge were
inherently perceptual. Since then, developments in logic, statistics,
and programming languages have inspired amodal theories that rest on
principles fundamentally different from those underlying perception.
In addition, perceptual approaches have become widely viewed as
untenable because they are assumed to implement recording systems, not
conceptual systems. A perceptual theory of knowledge is developed here
in the context of current cognitive science and neuroscience. During
perceptual experience, association areas in the brain capture bottom-up
patterns of activation in sensory-motor areas. Later, in a top-down
manner, association areas partially reactivate sensory-motor areas to
implement perceptual symbols. The storage and reactivation of perceptual
symbols operates at the level of perceptual components – not at
the level of holistic perceptual experiences. Through the use of
selective attention, schematic representations of perceptual components
are extracted from experience and stored in memory (e.g., individual
memories of green, purr, hot). As memories of the same
component become organized around a common frame, they implement
a simulator that produces limitless simulations of the component
(e.g., simulations of purr). Not only do such simulators develop for aspects of sensory experience, they also develop for aspects
of proprioception (e.g., lift,run) and introspection
(e.g., compare,memory,happy, hungry). Once
established, these simulators implement a basic conceptual system that
represents types, supports categorization, and produces categorical
inferences. These simulators further support productivity, propositions,
and abstract concepts, thereby implementing a fully functional
conceptual system. Productivity results from integrating simulators
combinatorially and recursively to produce complex simulations.
Propositions result from binding simulators to perceived individuals
to represent type-token relations. Abstract concepts are grounded in
complex simulations of combined physical and introspective events.
Thus, a perceptual theory of knowledge can implement a fully functional
conceptual system while avoiding problems associated with amodal symbol
systems. Implications for cognition, neuroscience, evolution,
development, and artificial intelligence are explored.
The neural substrates of recollection and familiarity
Authors: Yonelinas Andrew P. , Kroll Neal E. A. , Dobbins Ian G. , Lazzara Michele , Knight Robert T.
Published: July 2002

Aggleton & Brown argue that a hippocampal-anterior
thalamic system supports the “recollection” of
contextual information about previous events, and that a separate
perirhinal-medial dorsal thalamic system supports detection of
stimulus “familiarity.” Although there is a growing body
of human literature that is in agreement with these claims, when
recollection and familiarity have been examined in amnesics using the
process dissociation or the remember/know procedures, the results do
not seem to provide consistent support. We reexamine these studies
and describe the results of an additional experiment using a receiver
operating characteristic (ROC) technique. The results of the
reanalysis and the ROC experiment are consistent with Aggleton &
Brown's proposal. Patients with damage to both regions exhibit
severe deficits in recollection and smaller, but consistent, deficits
in familiarity.
Short-form versions of the MacArthur Communicative Development Inventories
Authors: FENSON LARRY , PETHICK STEVE , RENDA CONNIE , COX JEFFREY L. , DALE PHILIP S. , REZNICK J. STEVEN
Published: July 2002

The MacArthur Communicative Development Inventories (CDIs) are a pair of widely used
parent-report instruments for assessing communicative skills in infants and toddlers. This report
describes short-form versions of the CDIs and their development, summarizes newly available
normative data and psychometric properties of the instruments, and discusses research and
clinical applications. The infant short form (Level I, for 8- to 18-month-olds) contains an
89-word checklist for vocabulary comprehension and production. The two parallel versions of
the toddler short form (Level II, Forms A and B, for 16- to 30-month-olds) each contain a
100-word vocabulary production checklist and a question about word combinations. The forms
may also be useful with developmentally delayed children beyond the specified age ranges.
Copies of the short forms and the normative tables appear in the appendices.
Some results of uniform distribution in the multidimensional torus
Authors: HOST BERNARD
Published: July 2002

This paper contains a generalization to the $d$-torus $\mathbb{T}^d$ of earlier results (B. Host. Nombres normaux, entropie, translations. Israel J. Math. 91 (1995), 419–428). Given a probability measure $\mu$ on and an endomorphism $T$ of $\mathbb{T}^d$, we explore the relations between three properties: the uniform distribution of the sequence $(T^n\mathbf{t})$ for $\mu$-almost all $\mathbf{t}$; the behaviour of $\mu$ relative to the translations by some rational subgroups of $\mathbb{T}^d$; and the entropy of $\mu$ for another endomorphism $S$ of $\mathbb{T}^d$.
Sur l'ergodicité rationnelle et les propriétés ergodiques du flot géodésique dans les variétés hyperboliques
Authors: ROBLIN THOMAS
Published: July 2002

Cet article est consacré à la théorie ergodique du flot géodésique sur le fibré unitaire tangent d'une variété hyperbolique relativement à la mesure de Sullivan associée à une mesure conforme de Patterson–Sullivan. Nous prouvons notamment que si le flot géodésique est ergodique alors il est rationnellement ergodique de type asymptotique donné par la série de Poincaré du groupe d'isométries discret associé. Pour ce faire, de nouveaux résultats sur les mesures de Patterson–Sullivan sont introduits. Nous obtenons en conséquence des résultats généraux d'équirépartition asymptotique concernant la série de Poincaré. Nous approfondissons sur d'autres points les propriétés ergodiques du flot géodésique. Ces résultats se généralisent directement pour un groupe agissant sur un espace CAT$(-1)$.
An exceptional set in the ergodic theory of rational maps of the Riemann
sphere
Authors: ABERCROMBIE A. G. , NAIR R.
Published: July 2002

A rational map $T$ of degree not less than two is known to
preserve a measure, called the conformal measure, equivalent to
the Hausdorff measure of the same dimension as its Julia set $J$ and
supported there, with respect to which it is ergodic and even
exact. As a consequence of Birkhoff's pointwise ergodic theorem
almost every $z$ in $J$ with respect to the conformal measure
has an orbit that is asymptotically distributed on $J$ with
respect to this measure. As a counterpoint to this, the following
result is established in this paper. Let $\Omega(z)=\Omega_{T}(z)$ denote the closure of the set
$\{T^{n}(z):n=1,2,\ldots\}$. For any expanding rational map $T$ of
degree at least two we set
\[
S(z_{0})=\{z\in J:z_{0}\not\in \Omega_{T}(z)\}.
\]
We show that for all $z_{0}$ the Hausdorff dimensions of $S(z)$
and $J$ are equal.
The Dynamics of Popular Reactions to Democratization in Korea
Authors: Shin Doh Chull , McDonough Peter
Published: July 2002

The central argument of this paper is that, rather than simply absorbing democratic values diffusely, Koreans have acquired their support for democratization incrementally through experience with the consequences of regime change. In order to account for this pattern, we develop an empirical model that distinguishes between democracy as an ideal (desirability) and democracy understood as a viable political system (suitability). We draw on a survey of the Korean public to demonstrate that changes in these dimensions follow distinct trajectories, according to the recollections of our respondents, during the course of democratization. While beliefs about democracy-in-principle appear to be fairly impervious to political events and socioeconomic conditions, attitudes toward democracy-in-practice reflect a learning curve as the transition unfolds. We estimate the relative impact of evaluations of the economy, of the quality of life, and of governmental performance and political experience on support for democracy in practice. On the whole, democratic commitment is ‘earned’ through increasingly favorable perceptions of improvements in the quality of life, in economic growth, and especially in the performance of successive democratic governments, as contrasted with the workings of the previous authoritarian regime.
When and why frail elderly people give up independent living: The Netherlands as an example
Authors: STEVERINK NARDI
Published: July 2002

As yet the determinants of the need for nursing homes and old age homes are not clearly understood. This may be due to the fact that care facilities providing different levels of care may yield different predictors of use. Moreover, the absence of theory and ignorance of the problems with ‘use‘ as the dependent variable, may be responsible for this. In this study these issues are addressed explicitly. The study focuses on the need for living in an old age home and a theoretical model predicts under what circumstances frail elderly people will express the need for living in such a home. Findings show that, as hypothesised, loss of comfort and affection are among the main predictors of a strong orientation towards living in an old age home. Resources to counter the loss of comfort and affection – a spouse, income, home adaptations, private help, informal and formal home care – were only partly effective in their hypothesised function of deterring orientation towards living in an old age home. Pressure from others to apply for an old age home had the strongest effect. The findings are discussed and some implications for policy are considered.
Design of parallel
robots in microrobotics
Authors: Pernette Eric , Henein Simon , Magnani Ivo , Clavel Reymond
Published: July 2002

During the past few years, there has been an increasing demand in the
field of precision engineering for fine motion in multi-degrees of freedom
systems. These applications motivated the development of a new robotics field
called microrobotics. In this paper, we review both the design guidelines for
microrobots and the advantages of using parallel robots in very high precision
applications. Parallel micromanipulators using elastic joints as well as
structures manufactured in single solid and metallic bellows are
introduced.
Global stabilization for constrained robot motions with constraint uncertainties
Authors: Wang Danwei , Soh Y. C. , Ho Y. K. , Müller Peter C.
Published: July 2002

In this paper, the global stability problem for constrained robot motions in the presence of constraint uncertainties is investigated. We focus on the uncertainties in the constraint functions and their effects on the global stability. PD type controllers are used and conditions for global stability are developed using Lyapunov's direct approach. In the presence of the constraint uncertainties under investigation, the desired position and constraint force can be guaranteed with global asymptotic convergence. The developed conditions for feedback gain selections clearly show the effects of the constraint uncertainties. For the case when the velocity measurements are not available, conditions for
global stability regulation are also established and the robot controller uses only the measurements of the position angles. Finally, we consider the case where the robot joints are flexible and global stability conditions are given.
Presenting music live, audio-visually or aurally – does it affect listeners' experiences differently?
Authors: Finnäs Leif
Published: July 2002

This article reviews research regarding the question whether presenting music live, audio-visually or only aurally makes any difference for listeners' experiences. Most factors that characterise live performance could be supposed to enhance listeners' cognitive, affective and evaluative experiences. However, it is often hard to predict the exact influence of the visual stimuli that relate to audio-visual, and mostly also to live musical presentation. Many studies show that live music has positive effects on listeners' experience. However, there is little systematic research that compares live music with other modes of presentation. Studies comparing the effects of audio-visual and aural presentation have yielded rather mixed results. There is an obvious need for well-controlled studies on the effects of live music and on audio-visual music presentation based mainly on musico-psychological rather than visual-artistic principles. The research needs to take account of the variables that are crucial for understanding the effects of different modes of presentation.
A TOOL TO IMPROVE QUALITY OF REPORTING PUBLISHED ECONOMIC ANALYSES
Authors: Gerard Karen , Seymour Janelle , Smoker Irenie
Published: July 2002

Objectives: To test the feasibility of obtaining a baseline level
of quality of reporting for cost-utility analysis (CUA) studies using the
British Medical Journal economic submissions checklist, test
interrater reliability of this tool, and discuss its longer term implications.

Methods: CUA studies in peer-reviewed English language journals in
1996, assessed using the British Medical Journal checklist, a quality
index, and interrater reliability correlations.

Results: Forty-three CUA studies were assessed, with 23 checklist
items acceptable and 10 items inadequate. Lowest quality scores were reported
in specialist medical journals. Proportional agreement between assessors was
over 80%.

Conclusions: The British Medical Journal checklist is a
feasible tool to collect baseline information on the quality of reporting in
journals other than the British Medical Journal. Editors of
specialist medical journals are in greatest need of economic guidance. If
handled carefully, they might consider adopting the British Medical
Journal checklist.
PREOPERATIVE EVALUATION IN ELECTIVE SURGERY
Authors: Asua José , López-Argumedo Marta
Published: July 2002

Objectives: To collect and summarize information published by

INAHTA agencies on the indications, habitual attitudes and practices,

and economic and legal implications of preoperative evaluation in

elective surgeries.

Method: The authors appraised the information

contained in six papers published between 1989 and 1999 in Sweden,

France, Basque Country, the Netherlands, United Kingdom, and

Catalonia. The section on indications in preoperative evaluation

does not present global conclusions. The sections addressing

habitual attitudes and practices among physicians and those

addressing economic and legal considerations cover only the

similarities among the reports and the main ideas relating to these

issues.

Results: The conclusions found in the reports about indications

in preoperative evaluation are similar or differ slightly, e.g., as

regards age limits in patients for whom the tests are recommended.

However, more important differences are shown in other areas,

especially in reports where consensus methods were used. In some

instances, the opinions, attitudes, and customary practices of

professionals during the preoperative stage do not concur with the

recommendations extracted from the assessment reports and the

customary practice of doctors. In relation to economic

considerations, a substantial quantity of resources could be

liberated if the recommended general clinical practices were

followed. From the point of view of civil law, the evidence-based

recommendations could be considered as a

kind of coded lex artis.
MODELING COST OF TREATMENT WITH NEW TOPICAL TREATMENTS FOR GLAUCOMA
Authors: Kobelt Gisela , Jönsson Linus
Published: July 2002

Several new topical agents have been introduced recently and it can be
expected that the treatment of glaucoma will change, depending on how
effectively these agents control intraocular pressure (IOP). IOP is considered
the major risk factor in the development of glaucomatous damage. In order to
estimate the impact of these new agents on the cost of treating glaucoma, a
simulation model was created to estimate the cost of treating patients with a
recent diagnosis of primary open-angle glaucoma or ocular hypertension in
different countries. The Markov model is based on retrospective chart reviews
in different countries and calculates only cost, not outcome. Results are
presented for France and the United Kingdom, where current treatment appeared
to be comparable. Average one-year costs per patient with current treatment
were FF2,389 (US $389) and £380 (US $627), respectively. Costs with the
new treatments were lower than with current therapy.
The DiSC ASSAY
Authors: Mason James M. , Drummond Michael F. , Bosanquet Andrew G. , Sheldon Trevor A.
Published: July 2002

The differential staining cytotoxicity (DiSC) assay involves in vitro drug
panel testing against patient tumor cells to identify optimal therapy. This
observational study investigated whether DiSC assay guided treatment could
improve outcome in patients with chronic lymphocytic leukemia. A cohort of 178
patients were categorized either as sensitive to drugs in vitro and receiving
a sensitive drug in vivo, sensitive in vitro but not treated with a sensitive
drug, or having disease resistant to all drugs tested in vitro. Response and
survival for these patient categories were compared using multivariate
regression techniques. Patients receiving a sensitive drug, compared with
those who though having sensitivity did not, had a higher remission rate (odds
ratio, 6.5; 95% CI, 2.91–14.53) and reduced death rate (hazard ratio,
0.29; 95% CI, 0.16–0.53). Having adjusted for all known confounding
factors, the results suggest that in vitro drug sensitivity is an important
independent prognostic variable to include in future trials, and that the DiSC
assay may be a cost-effective use of health resources: the estimated
incremental cost-effectiveness was £1,470 per life-year gained. A
randomized controlled trial is required to confirm the benefit and estimate
reliably the potential impact of assay-guided choice of therapy.
Spatial heterogeneity of element and litter turnover in a Bornean rain forest
Authors: Burghouts T. B. A. , Straalen N. M. Van , Bruijnzeel L. A.
Published: July 2002

ABSTRACT. The spatial heterogeneity of element fluxes was quantified by measuring litterfall, throughfall and litter decomposition for 1 y in 30 randomly located sampling areas in a lowland dipterocarp rain forest. The idea tested was that turnover of elements is more variable than turnover of dry matter in a forest with extremely high tree species diversity. In spite of the low fertility of the soil (an ultisol), total litter production (leaves, trash, and wood <2 cm in diameter) was high (1105 g m−2 y−1) with inputs to the forest floor of carbon, nitrogen, phosphorus, calcium, magnesium, potassium, manganese and iron of 550, 15.3, 0.47, 6.26, 2.49, 4.75, 0.95 and 0.14 g m−2 y−1 respectively. Throughfall was 81% of the annual rainfall and transferred 22.2, 1.37, 0.14, 1.07, 0.67, 0.39, 7.92, <0.06, and <0.06 g m−2 y−1 of organic carbon, nitrogen (all forms), phosphorus, sulphur, calcium, magnesium, potassium, manganese and iron, respectively. Average turnover rates of nutrients in litter were highest for potassium and decreased in the sequence calcium, magnesium, carbon, nitrogen and phosphorus. Concentrations of phosphorus, nitrogen and potassium in litterfall, litter mass and topsoil were closely correlated with each other. Concentrations of calcium and manganese were positively correlated with each other and with elevation. Variations in leaf chemistry and total litterfall caused the spatial heterogeneity of element input to the forest floor to have a coefficient of variation of 30 — 70%, depending on the element. Due to the strong positive correlation between element fluxes and pools, the spatial variability of turnover rates (CV c. 20%) was lower than that of element input. Turnover rates for K varied by a factor of 4, and for Ca by a factor of 2.8 when the different sites were compared. The results strongly suggest that the most important factor determining spatial heterogeneity of organic matter and element dynamics on the forest floor is the site-specific amount of leaf fall, rather than spatially variable decomposition rates.
Dispersal of Miconia argentea seeds by the leaf-cutting ant Atta colombica
Authors: Dalling J. W. , Wirth Rainer
Published: July 2002

While leaf-cutter ants are thought to collect mainly vegetative plant material, they have also been observed collecting seeds or fruit parts on the forest floor (Alvarez-Buylla & Martínez-Ramos 1990, Kaspari 1996). For example, leaf-cutter ants have been observed carrying considerable numbers of Brosimum alicastrum Sw. and Cecropia spp. seeds into their nests (Wirth 1996) and Leal & Oliveira (1998; pers. comm.) found them foraging on the fruits and seeds of 19 different species of Brazilian cerrado vegetation, including six Miconia species. Under some circumstances, seed removal and relocation by leaf cutter ants might even be sufficient to affect local recruitment patterns of trees. For example, in Costa Rica, Atta cephalotes can remove all fallen fig fruit from beneath a Ficus hondurensis crown in a single night (Roberts & Heithaus 1986), while in Venezuela, seedling recruitment of the savanna tree Tapirira velutinifolia was positively associated with the seed harvesting and seed cleaning activities of the ant Atta laevigata (Farji Brenner & Silva 1996).
Light or presence of host trees: which is more important for the strangler fig?
Authors: Athreya Vidya R.
Published: July 2002

Strangler fig density varied considerably in the evergreen forest of Karian Shola National Park, southern India, with 11 individuals ha−1 in an open trail area and 5.6 individuals ha−1 within the primary forest area. The index of light level was assessed by estimating the percentage of upper canopy cover along the longitudinal centre of ten, 500-m × 20-m plots in each of the two areas of the evergreen forest. However, the increase in strangler fig density was not correlated to light levels but was significantly correlated to the numbers of their main host species in the two areas. In Karian Shola National Park, strangler figs occurred predominantly on a few host species with 20 and 50% of strangler figs growing on Vitex altissima, Diospyros bourdilloni and Eugenia/Syzygium spp. in the primary forest and trail areas respectively. Both young and established strangler figs were recorded mainly on larger individuals of their host trees indicating that older host trees are likely to be more suitable for the germination and establishment of strangler figs. The reason for the above could be the higher incidence of humus-filled and decaying regions in the older host trees which would provide an assured supply of nutrients for the establishing strangler fig.
Growth responses of seedlings of two neotropical pioneer species to simulated forest gap environments
Authors: Dalling J. W. , Lovelock C. E. , Hubbell S. P.
Published: July 2002

Traditional shade house experiments that expose plants to relatively uniform irradiance and light quality are inadequate to characterize the morphological, allocational and physiological plasticity that seedlings show to different gap environments. Here the design of a pot experiment is described that simulates the daily time course of irradiance and light quality in idealized gaps of six different sizes. Differences in response to gap size are illustrated using data from two pioneer species, Ochroma pyramidale, which recruits exclusively in large gaps and clearings, and Luehea seemannii, which colonizes small branchfall gaps as well as large gaps. Ochroma outperformed Luehea in relative growth rate in all except the smallest simulated gap size. Ochroma's superior performance in the larger gaps could be attributed to a larger proportional investment in leaf biomass (i.e. a higher leaf area ratio, LAR), and higher photosynthetic rates both on a leaf area and leaf mass basis. In the smallest simulated gaps LAR was not significantly different between the species, but Ochroma maintained a higher net assimilation rate. These results fail to support the suggestion that gap partitioning among pioneer species arises directly from morphological and biochemical specialization to particular gap light environments. Instead, it is suggested that partitioning may result from a trade-off between seedling growth and mortality determined by species allocational patterns and mediated by interactions with herbivores and pathogens.
Combining linear programming and satisfiability solving for resource planning
Authors: WOLFMAN STEVEN A. , WELD DANIEL S.
Published: July 2002

Compilation to Boolean satisfiability has become a powerful paradigm for solving artificial intelligence problems. However, domains that require metric reasoning cannot be compiled efficiently to satisfiability even if they would otherwise benefit from compilation. We address this problem by combining techniques from the artificial intelligence and operations research communities. In particular, we introduce the LCNF (Linear Conjunctive Normal Form) representation that combines propositional logic with metric constraints. We present LPSAT (Linear Programming plus SATisfiability), an engine that solves LCNF problems by interleaving calls to an incremental Simplex algorithm with systematic satisfaction methods. We explore several techniques for enhancing LPSAT's efficiency and expressive power by adjusting the interaction between the satisfiability and linear programming components of LPSAT. Next, we describe a compiler that converts metric
resource planning problems into LCNF for processing by LPSAT. Finally, the experimental section of the paper explores several optimisations to LPSAT, including learning from constraint failure and randomised cutoffs.
Formalisms for multi-agent systems
Authors: D'INVERNO MARK , FISHER MICHAEL , LOMUSCIO ALESSIO , LUCK MICHAEL , DE RIJKE MAARTEN , RYAN MARK , WOOLDRIDGE MICHAEL
Published: July 2002

As computer scientists, our goals are motivated by the desire to improve computer systems in some way: making them easier to design and implement, more robust and less prone to error, easier to use, faster, cheaper, and so on. In the field of multi-agent systems, our goal is to build systems capable of flexible autonomous decision making, with societies of such systems cooperating with one-another. There is a lot of formal theory in the area but it is often not obvious what such theories should represent and what role the theory is intended to play. Theories of agents are often abstract and obtuse and not related to concrete computational models.
A Report on Expert Assistants at the Autonomous Agents Conference
Authors: RAO ANAND S.
Published: July 2002

This report summarises the papers presented in the expert assistants area at the First International Conference on Autonomous Agents. It describes the relationship between the expert assistants area and the other areas of the conference, and identifies the major research themes within this area.
What Chance Software Agents?
Authors: CRABTREE BARRY
Published: July 2002

Software agents have come a long way in the last ten or so years. This paper looks at the practical challenges many software agent developers face including: interfacing to legacy systems; developing distributed systems; agent competence; and trust and privacy issues. Because it covers such a broad area, it will focus on how the problems and issues have changed over the years, and highlight some of the perennial problems.