bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual Frequency DGPS Service for Combating Ionospheric Interference
Authors: Ørpen Ole , Zwaan Henk
Published: July 2002

The 11-year solar sunspot cycle is approaching a maximum in 2000. The sunspot activity
causes an increase in the solar flux, charged particles and electromagnetic rays emitted from
the Sun. This solar flux affects the ionosphere, thus influencing the transmission of radio
waves through the ionosphere. The GPS satellite navigation system is affected in that the
transit time of the signals varies, introducing position errors. Also GPS equipment may
experience degraded performance in tracking of the GPS satellites due to scintillations,
rapidly varying amplitude and phase of the GPS signal. The equatorial and high latitude
regions are most severely affected by this increased ionospheric activity. Experience has shown
that, in equatorial regions, errors of 10–20 m may be introduced in Differential GPS services,
even on distances down to a few hundred kilometres from the reference station. During the
peak of the solar cycle, for the next 3–4 years, this situation will rather be the rule than the
exception in the affected areas. Fugro has introduced an enhanced real-time DGPS service
utilising dual frequency GPS called Starfix-Plus in selected areas. This service removes
ionospheric delay errors by calculating the delay using dual frequency GPS receivers on the
reference stations and the mobiles. The resulting accuracy is down to a few metres, even
using reference stations up to 2000 km away. This increases the availability and redundancy
of usable reference stations in a region, increasing the probability that the required accuracy
is available, even if individual stations are not available due to scintillations or for other
reasons.
Inertial Measurement Technology in the Satellite Navigation Environment
Authors: Strachan Victor F.
Published: July 2002

Inertial measurement technology can make a valuable contribution to the development of
autonomous, sole-means Satellite Navigation Systems. The integration of inertial measurement
technology and GPS can enable a significant performance improvement to the various
configurations of GPS, WAAS and LAAS. This paper provides a conceptual discussion of
the safety and performance benefits that inertial measurement and integration technology
can bring to the satellite navigation environment.
Sun Compass and Wind Drift Compensation in Migrating Butterflies
Authors: Srygley Robert B. , Oliveira and Evandro G.
Published: July 2002

Migrating pierid butterflies use a sun compass in order to head in a preferred flight direction. When blown off-course by the wind, butterflies adjust their heading to compensate for cross-track wind drift. They are capable of drift compensation over water when and where landmarks are visible on the shore. They are also capable of a more inaccurate form of drift compensation over the sea when and where landmarks are not visible.
Urbanization in the Pacific: environmental change, vulnerability and human security
Authors: Cocklin Chris , Keen Meg
Published: July 2002

The world is in the midst of a substantial urban transition, but the impacts of this on the environment and human societies are not fully understood. Very little attention has been paid to urbanization processes in developing countries with smaller populations, despite the evident problems associated with urbanization. There are both biophysical and social vulnerabilities associated with urbanization in the South Pacific and these vulnerabilities affect human security. The biophysical vulnerabilities include the fragile environments of the island nations, limited land resources, shortages of basic resources, and the risks associated with global warming. The ability to respond to these problems is constrained by social vulnerabilities, notably weak economies, difficulties associated with land ownership, and institutional limitations. There is a need for institutional reform, improved planning, better urban resource management, and greater regional cooperation, if Pacific island nations are to respond effectively to rapid urbanization and global change.
Assessing trail conditions in protected areas: application of a problem-assessment method in Great Smoky Mountains National Park, USA
Authors: LEUNG YU-FAI , MARION JEFFREY L.
Published: July 2002

The degradation of trail resources associated with expanding recreation and tourism visitation is a growing management problem in protected areas worldwide. In order to make judicious trail and visitor management decisions, protected area managers need objective and timely information on trail resource conditions. This paper introduces a trail survey method that efficiently characterizes the location and lineal extent of common trail problems. The method was applied to a large sample of trails within Great Smoky Mountains National Park, a high-use protected area in the USA. The Trail Problem-Assessment Method (TPAM) employs a continuous search for multiple indicators of pre-defined tread problems, yielding census data documenting the location, occurrence and extent of each problem. The present application employed 23 different indicators in three categories to gather inventory, resource condition, and design and maintenance data of each surveyed trail. Seventy-two backcountry hiking trails (528 km), or 35% of the Park's total trail length, were surveyed. Soil erosion and wet soil were found to be the two most common impacts on a lineal extent basis. Trails with serious tread problems were well distributed throughout the Park, although trails with wet muddy treads tended to be concentrated in areas where horse use was high. The effectiveness of maintenance features installed to divert water from trail treads was also evaluated. Water bars were found to be more effective than drainage dips. The TPAM was able to provide Park managers with objective and quantitative information for use in trail planning, management and maintenance decisions, and is applicable to other protected areas elsewhere with different environmental and impact characteristics.
An epidemiologic study of herpes simplex virus type 1 and 2
infection in Japan based on type-specific serological assays
Authors: HASHIDO M. , LEE F. K. , NAHMIAS A. J. , TSUGAMI H. , ISOMURA S. , NAGATA Y. , SONODA S. , KAWANA T.
Published: July 2002

A seroepidemiologic study of herpes simplex virus type 1 (HSV-1)
and 2 (HSV-2) was
performed on Japanese adults. Serum samples collected between 1985–9
from a total of 536
healthy adults, female prostitutes, males with sexually transmitted diseases
(STD), homosexual
men, and pregnant women were studied by immunodot assays using HSV type-specific

antigens, glycoproteins G (gG1 and gG2). HSV-1 infections correlated mostly
with age and
was widely prevalent among subjects <40 years. HSV-2 prevalence varied
greatly among
subgroups defined by sexual activity and was associated with risk behaviours
for prostitution,
infection with STD, and homosexual activity. HSV-2 seroprevalence was highest
among
prostitutes (80%), lowest among pregnant women (7 %), and intermediate
in STD patients
(23%) and homosexuals (24%). Because HSV-1 infection during childhood has
been
decreasing, primary genital HSV-2 infection, with its higher frequency
of clinical
manifestations, will become a greater burden to the public health in Japan.
Risk factors for the occurrence of sporadic Salmonella
enterica serotype enteritidis infections in children in France:

a national case-control study
Authors: DELAROCQUE-ASTAGNEAU E. , DESENCLOS J.-C. , BOUVET P. , GRIMONT P. A. D.
Published: July 2002

To determine risk factors associated with the occurrence of sporadic
cases of Salmonella
enteritidis infections among children in France, we conducted a matched
case-control study.
Cases were identified between 1 March and 30 September 1995. One hundred
and five pairs of
cases and controls matched for age and place of residence were interviewed.
In the 1–5 years
age group, illness was associated with the consumption of raw eggs or undercooked
egg-
containing foods (OR 2·4, 95% CI 1·2–4·8). Storing
eggs more than 2 weeks after purchase was
associated with Salmonella enteritidis infection (OR 3·8,
95% CI 1·4–10·2), particularly during
the summer period (OR 6·0, 95% CI 1·3–26·8).
Cases were more likely to report a case of
diarrhoea in the household 10·3 days before the onset of symptoms,
particularly in the age
group [les ]1 year (P=0·01). This study confirms the link
between eggs and the occurrence of
sporadic cases of Salmonella enteritidis among children, highlights
the potential role of
prolonged egg storage and underlines the role of person-to-person transmission
in infants.
Epidemiology of respiratory syncytial virus infection among
paediatric patients in Hong Kong: seasonality and disease impact
Authors: CHAN P. K. S. , SUNG R. Y. T. , FUNG K. S. C. , HUI M. , CHIK K. W. , ADEYEMI-DORO F. A. B. , CHENG A. F.
Published: July 2002

In a 5-year retrospective survey of respiratory syncytial virus (RSV) infections among
hospitalized children, 1340 cases were identified of which, 98·4% were children <5 years old
with a male:female ratio of 1·5:1. Most cases occurred from April to September showing a
significant positive correlation with temperature and relative humidity. Community-acquired
infections accounted for 92·5% of the cases with a mean hospital stay of 5 days. The estimated
annual incidence of RSV infection requiring hospitalization was 2·5/1000 children <5 years
old with a mortality of 0·15% among hospitalized cases. On average, 248 children were
admitted each year to the 1400-bed acute regional hospital accounting for an expenditure of
HK $1.94 (∼US $0.25) million for hospitalization costs which equates to an annual cost in
excess of HK $6.67 (∼US $0.86) million for the whole of Hong Kong. An RSV vaccine
should be a priority.
Drug resistance rates of Mycobacterium tuberculosis strains
in Austria between 1995 and 1998 and molecular typing of
multidrug-resistant isolates
Authors: STAUFFER F. , MAKRISTATHIS A. , KLEIN J. P. , BAROUSCH W. , The Austrian Drug Resistant Tuberculosis Study Group
Published: July 2002

In this study the drug resistance pattern of 3559 Mycobacterium tuberculosis strains isolated in
Austria between 1995 and 98 was evaluated. Of these strains, 165 (4·6%) were resistant to one
or more drugs, 113 (3·2%) to one of the tested drugs and 53 (1·5%) to two or more drugs.
Monodrug resistance was observed most often to isoniazid (56 strains), followed by
streptomycin (44 strains). Resistance to rifampicin or ethambutol alone was rarely seen (12
strains and 1 strain, respectively). Of the 53 strains resistant to 2 or more drugs, 25 were
resistant to isoniazid and streptomycin, while 17 were multidrug resistant. Molecular typing
revealed a large diversity among the multidrug-resistant strains.
Diversity and evolution of macrohabitat use, body size and morphology in a monophyletic group of Neotropical pitvipers (Bothrops)
Authors: Martins Marcio , Araujo Marcio S. , Sawaya Ricardo J. , Nunes Renato
Published: July 2002

The Neotropical pitviper genus Bothrops comprises about 40 species, which occur in all main ecosystems of cis‐Andean South America. We explored the relationships of body size and form (tail length and stoutness) with macrohabitat use in 20 forms of Bothrops. Semi‐arboreal habits appeared only in forest forms. Semi‐arboreals are significantly more slender and have longer tails than terrestrials; body size is not significantly different between terrestrials and semi‐arboreals. Within Bothrops, independent contrasts for macrohabitat use were significantly correlated with contrasts of tail size (positively) and stoutness (negatively); thus, the more arboreal the species, the longer its tail and the more slender its body. Contrasts of adult body size seems to remain constant over the lower range of macrohabitat use, but to decrease in species of Bothrops which are more arboreal. Reconstructions of character states indicate that: (1) the ancestor of Bothrops was a small, stout, terrestrial species; (2) semi‐arboreal habits appeared one to three times in the genus; (3) a decrease in stoutness and an increase in tail length occurred along with an increase in arboreality in some clades. Although macrohabitat use seems to be important in determining body form in Bothrops, our results also indicate that tail size, stoutness and body size may also be affected by selective agents other than macrohabitat use. The selective agents responsible for the shifts in macrohabitat use in Bothrops are still uncertain, although they may have included prey availability and/or predation pressure. The plasticity of macrohabitat use, morphology and body size described in this study may have been key features that facilitated the highly successful ecological diversification of Bothrops in South America.
Interactions between the red squirrel (Sciurus vulgaris), great tit (Parus major) and jackdaw (Corvus monedula) whilst using nest boxes
Authors: Shuttleworth C. M.
Published: July 2002

This paper reports upon the use of nest boxes in coniferous woodland by the red squirrel Sciurus vulgaris, great tit Parus major and the jackdaw Corvus monedula over a 6‐year period from 1994 to 1999. Initially 30 nest boxes were erected with eight additional boxes being put up in 1995. In the period 1994 to 1997, red squirrels were found to use nest boxes regularly as nesting and breeding sites (7.8 ± 1.0 se litters found annually). Box use was greatest in the summer and autumn months (70% of boxes being used at least once) and declined through the winter (50%) into the spring (45%). The presence of great tit clutches and broods in the spring did not prevent red squirrels from occupying boxes. Only 28% (n= 12) of all the recorded great tit clutches produced fledgling young in 1994 to 1997 and red squirrels were found to have consumed some of the chicks and eggs. The establishment of a jackdaw colony within the woodland led to 86% of the nest boxes being used by the birds in the spring of 1999. Red squirrel occupation of boxes in the spring declined to 7% and only three litters were recorded that year. The study showed that the jackdaw has the capacity to dominate nest boxes during the spring months despite the high density of red squirrels within the reserve.
Postnatal growth in body length and mass of polar bears (Ursus maritimus) at Svalbard
Authors: Derocher A. E. , Wiig Ø.
Published: July 2002

The von Bertalanffy curve was used to examine growth patterns in both body length and mass of female and male polar bears Ursus maritimus live‐captured near Svalbard, Norway. A longer growth period in males resulted in pronounced sexual dimorphism in both body length and mass. Males were 1.16 times longer and 2.10 times heavier than females. The asymptotic body length of female and male polar bears from Svalbard was smaller than that for polar bears in four of six previously studied populations. Asymptotic body mass of females from Svalbard was lower than other previously studied populations, while males were generally lighter. The reasons for the lighter bears in Svalbard are unclear, but we believe they were not related to sampling error, ecosystem productivity, or genetic differences. The high pollution load of polar bears in Svalbard may have affected body size but this potential factor could not be assessed. The generally smaller size of polar bears in Svalbard was consistent with density‐dependent growth effects but again, information on population density relative to carrying capacity was insufficient to assess this hypothesis.
Negative reactivity and attachment: Down syndrome's contribution to the
attachment–temperament debate
Authors: GANIBAN JODY , BARNETT DOUGLAS , CICCHETTI DANTE
Published: July 2002

This longitudinal study investigated the relation between negative reactivity and attachment
in children with Down syndrome (DS). Specifically, we examined whether extremely low
negative reactivity is associated with the enactment and organization of attachment behaviors. To
address this issue 30 infants with DS (13 female, 17 male) were observed in Ainsworth's
Strange Situation at 19 and 27 months. The intensity and duration of distress reactions were
coded in 15-s intervals throughout each Strange Situation episode. Children's distress
intensity during separations from caregivers was used to place children into Low versus
Moderate/High Negative Reactivity groups. In addition, ratings of infants' social
interactive behaviors (contact maintenance, proximity seeking, distance interaction, resistance,
and avoidance) were made for each episode and used to assess the quality of infants'
attachment relationships. The data indicated that there are high rates of Type A and D insecure
attachments within the DS population at each age studied. However, low negative reactivity was
not consistently related to the activation of the attachment behavioral system, or associated with
insecure attachment relationships. Alternative explanations for the high rate of insecure
attachments are discussed.
International adoption of institutionally reared children: Research and policy
Authors: GUNNAR MEGAN R. , BRUCE JACQUELINE , GROTEVANT HAROLD D.
Published: July 2002

This article summarizes the research on the developmental outcomes of postinstitutionalized

children and discusses the implications for social policy. Postinstitutionalized children often reach

their adoptive families with varying degrees of physical growth retardation, cognitive delays, and

socioemotional problems. Many children demonstrate remarkable recovery following adoption.

Unfortunately, some of the children continue to display significant problems that require

professional intervention. It appears that the children's recovery may be influenced by their

early experiences with their birth family and in institutional care, and there is suggestive evidence

that postadoption experiences also play a role. These findings indicate that preadoption and

postadoption services may support the outcome of postinstitutionalized children.
Diverse patterns of neuroendocrine activity in maltreated children
Authors: CICCHETTI DANTE , ROGOSCH FRED A.
Published: July 2002

Cortisol regulation was investigated in a sample of school-aged maltreated (n =
175) and demographically comparable low-income nonmaltreated (n = 209) children in
the context of a day camp research program. Overall group differences between maltreated and
nonmaltreated children were not found for average morning or average afternoon cortisol levels.
However, significant variations were found that were based on the subtypes of maltreatment that
the children had experienced. Maltreated children who had been both physically and sexually
abused (as well as neglected or emotionally maltreated) exhibited substantial elevations in
morning cortisol levels; children who had high (>1 SD) cortisol levels in both the
morning and afternoon were also overrepresented in the multiple abuse group. Developmental
timing of maltreatment did not account for these group differences, whereas the severity of sexual
abuse was implicated. In contrast to the multiple abuse group, a subgroup of physically abused
children showed evidence of a trend toward lower morning cortisol relative to nonmaltreated
children with a significantly smaller decrease in cortisol levels from morning to afternoon. The
findings are discussed in terms of the diversity of atypical cortisol regulation patterns that are
exhibited among maltreated children.
A positive view of self: Risk or protection for aggressive children?
Authors: HUGHES JAN N. , CAVELL TIMOTHY A. , GROSSMAN PAMELA B.
Published: July 2002

Children's ratings of competence and relationship quality were
used to examine the association between idealized or inflated
self-perceptions and level of aggression. Participants were 62
aggressive and 53 nonaggressive second and third graders. Ratings of
competence were based on the Pictorial Scale of Perceived Competence
and Social Acceptance for Young Children; ratings of relationship
quality were drawn from the Social Support Appraisals Scale and the
Network of Relationships Inventory. External ratings of competence and
relationship quality were obtained from mothers, teachers, and
peers. Compared to children who were nonaggressive, aggressive
children were more likely to rate personal competence and relationship
quality in a perfect or idealized manner and to show less
differentiation in their ratings of competence and relationship
quality. Aggressive children's self-rated competence and
relationship quality were also inflated relative to the ratings made
by others, whereas the self-ratings of nonaggressive children tended
to be underestimates of their functioning. The tendency for aggressive
children to idealize and to inflate ratings of competence and
relationship quality was associated with higher levels of
aggression. For aggressive children, a highly positive self-view is
construed—not as a protective factor or measurement error
— but as a defensive posture that places the child at added risk
and that impedes the progress of psychosocial interventions.
Psychopathology, mother–child interaction, and infant development:
Substance-abusing mothers and their offspring
Authors: BECKWITH LEILA , HOWARD JUDY , ESPINOSA MICHAEL , TYLER RACHELLE
Published: July 2002

The course of severe depressive symptoms from pregnancy to 6 months postpartum, as well
as the occurrence of severe paranoid symptoms prenatally, were examined by the Millon Clinical
Multiaxial Inventory I and the Beck Depression Inventory, in 78 women who were heavy,
chronic cocaine users and who retained custody of their children after birth. Six months
postpartum, the quality of caregiving was observed and assessed in the home, and the children
were assessed on the Bayley MDI Index in the laboratory. Mothers who were depressed and
paranoid prenatally, regardless of whether the depression continued to 6 months postpartum,
were less sensitive in caregiving than women without severe symptoms of paranoia or depression
during pregnancy or those who reported only depression that lifted by 6 months postpartum.
Mothers who were depressed prenatally and continued to be depressed by 6 months postpartum,
regardless of the presence or absence of paranoia, had infants who earned lower Bayley MDI
scores than the offspring of women without severe psychological symptoms or women whose
depression had lifted. Severe depressive symptoms during pregnancy, if they did not continue to
6 months postpartum, did not appear to adversely influence either caregiving or infant
functioning.
ADORNMENT AND IDENTITY
Authors: Aizpurúa Ilean Isel Isaza , McAnany Patricia A.
Published: July 2002

Excavations in Formative and Early Classic contexts
at the Maya site of K'axob have produced a sample
of 2,568 worked-shell ornaments crafted from both marine
and freshwater species. Predominantly shell beads, the
sample also includes unique pendants, figurines, and tinklers.
A high frequency of unfinished beads in Middle Formative
and early Late Formative midden contexts provides strong
evidence of localized shell working and trading connections
with the Caribbean. Personal adornment crafted from shell
is an important item in many burials, including those of
children. The most lavish disposal of shell, however, occurs
in one of the earliest Middle Formative interments at K'axob.
An adult male—who may have been a “founder”
of K'axob—was buried with 2,019 shell beads.
Through time, fewer individuals were buried with worked
shell as the intricacy of shell working became more elaborate
and possibly iconic of roles of authority. Interpretation
of archaeological patterns indicates that shell beads can
provide significant insight into the construction of social
identities.
The expressive power of higher-order types or, life without CONS
Authors: JONES NEIL D.
Published: July 2002

Compare first-order functional programs with higher-order programs allowing functions as
function parameters. Can the the first program class solve fewer problems than the second?
The answer is no: both classes are Turing complete, meaning that they can compute all
partial recursive functions. In particular, higher-order values may be first-order simulated
by use of the list constructor ‘cons’ to build function closures. This paper uses complexity
theory to prove some expressivity results about small programming languages that are less
than Turing complete. Complexity classes of decision problems are used to characterize the
expressive power of functional programming language features. An example: second-order
programs are more powerful than first-order, since a function f of type [Bool]-〉Bool is
computable by a cons-free first-order functional program if and only if f is in PTIME, whereas
f is computable by a cons-free second-order program if and only if f is in EXPTIME. Exact
characterizations are given for those problems of type [Bool]-〉Bool solvable by programs
with several combinations of operations on data: presence or absence of constructors; the
order of data values: 0, 1, or higher; and program control structures: general recursion, tail
recursion, primitive recursion.
Three algorithms on Braun trees
Authors: OKASAKI CHRIS
Published: July 2002

Among the many flavours of balanced binary trees, Braun

trees (Braun and Rem,

1983) are perhaps the most circumscribed. For any given

node of a Braun tree,

the left subtree is either exactly the same size as the

right subtree, or one element

larger. Braun trees always have minimum height, and the

shape of each Braun

tree is completely determined by its size. In return for

this rigor, algorithms that

manipulate Braun trees are often exceptionally simple and

elegant, and need not

maintain any explicit balance information.

Braun trees have been used to implement both flexible

arrays (Braun and Rem,

1983; Hoogerwoord, 1992; Paulson, 1996) and priority

queues (Paulson, 1996; Bird,

1996). Most operations involving a single element

(e.g. adding, removing, inspecting

or updating an element) take O(log n) time,

since the trees are balanced. We consider

three algorithmically interesting operations that

manipulate entire trees. First, we

give an O(log2n) algorithm

for calculating the size of a tree. Second, we show how

to create a tree containing n copies of some element

x in O(log n) time. Finally, we

describe an order-preserving algorithm for converting

a list to a tree in O(n) time.

This last operation is not nearly as straightforward

as it sounds!
Predictors of hospital admission and mortality in patients with chronic obstructive pulmonary disease
Authors: Yohannes AM , Connolly MJ
Published: July 2002

Hospital readmission rates for COPD patients are high, with two-week readmission rates of 22% being recorded in one study of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). In a separate study, patients admitted with PaCO2> 50 mm Hg had a readmission rate of 40% at six months. There are no agreed clinical evidence factors that determine readmission. A few studies have reported that readmission is associated with an individual’s inability to cope with the disease, and that anxiety and socioeconomic status are important variables. Others argue that readmission relates to severity of lung function abnormality, changes in atmospheric pollution, and impaired quality of life (QoL).
Rehabilitation in elderly people with visual impairment
Authors: Jack CIA , McGalliard JN
Published: July 2002

In England there are over 100 000 elderly people registered blind and a further 80 000 registered partially sighted. Visual impairment is common in the elderly population, with approximately 10% of people of 65 years of age and over having poor vision. The prevalence of visual problems appears to be much greater among older people in institutionalized care. A study of 100 elderly people living in residential homes in London revealed that 51% had cataract and 34% had significant refractive errors. A further study of patients attending a geriatric day centre found that about one-third had unrecognized visual loss.
Parametric polymorphism and operational equivalence
Authors: PITTS ANDREW M.
Published: July 2002

Studies of the mathematical properties of impredicative polymorphic types have for the
most part focused on the polymorphic lambda calculus of Girard–Reynolds, which is a
calculus of total polymorphic functions. This paper considers polymorphic types from a
functional programming perspective, where the partialness arising from the presence of
fixpoint recursion complicates the nature of potentially infinite (‘lazy’) data types. An
approach to Reynolds' notion of relational parametricity is developed that works directly on
the syntax of a programming language, using a novel closure operator to relate operational
behaviour to parametricity properties of types. Working with an extension of Plotkin's PCF
with ∀-types, lazy lists and existential types, we show by example how the resulting logical
relation can be used to prove properties of polymorphic types up to operational equivalence.
Varieties generated by languages with poset operations
Authors: BLOOM STEPHEN L. , ÉSIK ZOLTÁN
Published: July 2002

A V-labelled poset P can induce an operation
on
the languages on any fixed alphabet, as
well as an operation on labelled posets (as noticed by Pratt and Gischer
(Pratt 1986; Gischer 1988)). For any collection X of
V-labelled posets and any alphabet Σ we obtain an
X-algebra ΣX of languages on Σ.
We
consider the variety Lang(X) generated by these
algebras when X is a collection of nonempty ‘traceable
posets’. The current paper contains
several observations about this variety. First, we use one of the
basic results in Bloom and
Ésik (1996) to show that a concrete description of the
A-generated free algebra in Lang(X)
is the X-subalgebra generated by the singletons (labelled
a∈A) in the X-algebra of all
A-labelled posets. Equipped with an appropriate ordering, these
same
algebras are the free ordered algebras in the variety
Lang(X)[les ] of ordered language X-algebras.
Further, if one enriches the language algebras by adding either a binary
or
infinitary union operation, the
free algebras in the resulting variety are described by certain
‘closed’ subsets of the original
free algebras. Second, we show that for ‘reasonable sets’ X,
the variety Lang(X) has the
property that for each n[ges ]2, the n-generated free
algebra is a subalgebra of the 1-generated
free algebra. Third, knowing the free algebras enables us to show that
these varieties are
generated by the finite languages on a two-letter alphabet.
Final coalgebras as greatest fixed points in ZF set theory
Authors: PAULSON LAWRENCE C.
Published: July 2002

A special final coalgebra theorem, in the style of Aczel (1988), is proved within standard
Zermelo–Fraenkel set theory. Aczel's Anti-Foundation Axiom is replaced by a variant
definition of function that admits non-well-founded constructions. Variant ordered pairs and
tuples, of possibly infinite length, are special cases of variant functions. Analogues of Aczel's
solution and substitution lemmas are proved in the style of Rutten and Turi (1993). The
approach is less general than Aczel's, but the treatment of non-well-founded objects is
simple and concrete. The final coalgebra of a functor is its greatest fixedpoint.

Compared with previous work (Paulson, 1995a), iterated substitutions and solutions are
considered, as well as final coalgebras defined with respect to parameters. The disjoint sum
construction is replaced by a smoother treatment of urelements that simplifies many of the
derivations.

The theory facilitates machine implementation of recursive definitions by letting both
inductive and coinductive definitions be represented as fixed points. It has already been
applied to the theorem prover Isabelle (Paulson, 1994).
The music of prose offices in honour of English saints
Authors: HILEY DAVID
Published: July 2002

Some basic stylistic features of ten prose offices for English saints are
considered. The oldest is that for St Cuthbert (probably c. 930). Others are
for Dunstan of Canterbury, Edmund of East Anglia, Ethelwold of Winchester,
Kyneburga, Kyneswytha and Tybba of Peterborough, Mildred of Thanet, Oswald
of Northumbria, Oswald of Worcester, Swithun of Winchester, and Wulfstan of
Worcester. All were probably composed earlier than the office for Thomas of
Canterbury (soon after 1170), which with its rhymed, accentual verse text
marks a new type of office. Important musical features of these offices
include the deployment of chants in modal order, tonality that relies on a
framework of finalis and fifth (also the upper octave and lower fourth),
cadences approached from the note below, the use of responsory verse tones,
and formulaic melodies.
Cultural Engagement in Clinical Ethics: A Model for Ethics
Consultation
Authors: CARTER MICHELE A. , KLUGMAN CRAIG M.
Published: July 2002

In the rapidly evolving healthcare environment, perhaps
no role is in greater flux and redefinition than that of
the clinical bioethicist. The discussion of ethics
consultation in the bioethics literature has moved from
an ambiguous concern regarding its proper place in the
clinical milieu to the more provocative question of which
methods and theories should best characterize the intellectual
and practical work it claims to do. The American Society for
Bioethics and Humanities addressed these concerns in its
1998 report, Core Competencies for Health Care Ethics
Consultation. The report tries to answer the question
as to what disciplinary training, background experience, and
levels of knowledge in ethics the clinical ethics consultant
should have, and what specific skills and character traits the
clinical ethics consultant should cultivate. In addition to
acquiring knowledge of common bioethical issues, theoretical
concepts in ethical theory and moral reasoning, and health-related
law and policy, the report also recommends that ethics consultants
demonstrate knowledge of the health beliefs and perspectives
of patients and healthcare providers. In our opinion, this
recommendation underscores a crucial aspect of the practice of
ethics consultation in the increasingly multicultural settings
of healthcare institutions. Clearly, the dynamic of American life
and culture is permeated with diversity and variety as new groups
suffuse their own beliefs and faith perspectives into the health
sector. New immigrant groups force society to question traditional
healthcare practices and to accommodate changing medical needs.
Bioethics and Human Rights: A Historical Perspective
Authors: BAKER ROBERT
Published: July 2002

Bioethics and human rights were conceived in the
aftermath of the Holocaust, when moral outrage reenergized
the outmoded concepts of “medical ethics” and
“natural rights,” renaming them “bioethics,”
and “human rights” to give them new purpose.
Originally, the principles of bioethics were a means for
protecting human rights, but through a historical accident,
bioethical principles came to be considered as fundamental.
In this paper I reflect on the parallel development and
accidental divorce of bioethics and human rights to urge
their reconciliation.
Commentary
Authors: Davis John K.
Published: July 2002

Judith Thomson argues that a fetus may have a right
to life yet lack the right to use its mother's body
to stay alive. According to Kenneth Einar Himma, Thomson's
argument applies only to cases where the parties meet two
conditions. First, they must “have a history of physical
independence” and, second, they must be “autonomous
moral agents, capable of incurring obligations.”
Himma devises a case involving conjoined twins to show
why the mother–fetus case does not meet these conditions.
The effects of cell size and ploidy on cell allocation in mouse chimaeric blastocysts
Authors: Tang Pin-Chi , Ritchie William A. , Wilmut Ian , West John D.
Published: July 2002

In a previous study of mouse tetraploid[harr ]diploid chimaeric blastocysts, tetraploid cells were found to be more abundant in the trophectoderm than the inner cell mass (ICM) and more abundant in the mural trophectoderm than the polar trophectoderm. This non-random allocation of tetraploid cells to different regions of the chimaeric blastocyst may contribute to the restricted tissue distribution seen in postimplantation stage tetraploid[harr ]diploid chimaeras. However, the tetraploid and diploid embryos that were aggregated together differed in several respects: the tetraploid embryos had fewer cells and these cells were bigger and differed in ploidy. Each of these factors might underlie a non-random allocation of tetraploid cells to the chimaeric blastocyst. A combination of micromanipulation and electrofusion was used to produce two series of chimaeras that distinguished between the effects of cell size and ploidy on the allocation of cells to different tissues in chimaeric blastocysts. When aggregated cells differed in cell size but not ploidy, the derivatives of the larger cell contributed significantly more to the mural trophectoderm and polar trophectoderm than the ICM. When aggregated cells differed in ploidy but not cell size, the tetraploid cells contributed significantly more to the mural trophectoderm than the ICM. In both experiments the contributions to the polar trophectoderm tended to be intermediate between those of the mural trophectoderm and ICM. These experiments show that both the larger size and increased ploidy of tetraploid cells could have contributed to the non-random cell distribution that was observed in a previous study of tetraploid[harr ]diploid chimaeric blastocysts.
Impaired development of zygotes with uneven pronuclear size
Authors: Sadowy Sasha , Tomkin Giles , Munné Santiago , Ferrara-Congedo Toni , Cohen Jacques
Published: July 2002

The correlation between human zygote morphology and chromosomal anomalies after cleavage has not been well characterised. Commonly observed morphological qualities at the zygote stage have provided little insight into further development, and therefore selection for cryopreservation or transfer appears to be less specific than that at later stages of preimplantation development. The purpose of this work was to evaluate the relationship between aberrant pronuclear morphology and chromosomal anomalies after cleavage. Monospermic zygotes exhibiting two pronuclei where diameters differed by at least 4 μm were found to arrest at a significantly higher rate than zygotes with pronuclear diameters differing by less than 4 µm. In addition, a higher incidence of day 2 multinucleation was observed. Embryos deriving from zygotes with dysmorphic pronuclei that were not replaced or cryopreserved by day 3 of development were separated and fixed for fluorescence in situ hybridisation analysis of chromosomes X, Y, 13, 18 and 21. A significantly higher incidence of mosaicism was found in this group compared with others that had developed from zygotes with normal pronuclear morphology. Although the mechanism leading to this form of divergent pronuclear morphology is unclear, results suggest a correlation with oocyte cyto-plasmic immaturity.
BLACK ARTS, RUINED CATHEDRALS, AND THE GRAVE IN ENGRAVING: RUSKIN AND THE FATAL EXCESS OF ART
Authors: Siegel Jonah
Published: July 2002

TO SPEAK ABOUT JOHN RUSKIN’S anxious figures for engraved reproduction is to speak about his troubled relationship to a modernity in which excess and impermanence present complex and interrelated challenges. The ruined cathedral in my title occurs in lectures Ruskin delivered in 1857, and published the same year as The Political Economy of Art. Invited to speak at Manchester on the occasion of the Art-Treasures Exhibition, at the height of his fame as a critic, Ruskin responded to the moment with two lectures challenging much that the exhibition stood for. He offered the following apocalyptic description of the situation of art away from the self-congratulating festival. It is worth considering this passage — at once about art and about the responsibility for its blighting — in relation to the immense temporary structure built to house the Art-Treasures Exhibition (Figure 9):
The use of potential vorticity and water vapour imagery to validate numerical models
Authors: Mansfield D A
Published: July 2002

A comparison between potential vorticity (PV) fields and water vapour imagery shows a close relationship in the region of the polar front. Examples are given showing the nature of this relationship and how a mis‐match between the PV and the imagery can be used to detect errors in model analyses and forecasts. The nature of the relationship varies according to the synoptic situation and some of the possible pitfalls encountered by not applying additional checks using model humidity or ‘pseudo imagery’ fields are illustrated. Copyright © 1997 Royal Meteorological Society
The TREC question answering track
Authors: VOORHEES ELLEN M.
Published: July 2002

The Text REtrieval Conference (TREC) question answering track is an effort to bring the
benefits of large-scale evaluation to bear on a question answering (QA) task. The track has
run twice so far, first in TREC-8 and again in TREC-9. In each case, the goal was to retrieve
small snippets of text that contain the actual answer to a question rather than the document
lists traditionally returned by text retrieval systems. The best performing systems were able to
answer about 70% of the questions in TREC-8 and about 65% of the questions in TREC-9.
While the 65% score is a slightly worse result than the TREC-8 scores in absolute terms, it
represents a very significant improvement in question answering systems. The TREC-9 task
was considerably harder than the TREC-8 task because TREC-9 used actual users’ questions
while TREC-8 used questions constructed for the track. Future tracks will continue to
challenge the QA community with more difficult, and more realistic, question answering tasks.
An automated system that assists in the generation of document

indexes
Authors: HODGES JULIA , YIE SHIYUN , REIGHART RAY , BOGGESS LOIS
Published: July 2002

In this article, we describe AIMS (Assisted Indexing at

Mississippi State), a system intended to aid human document analysts

in the assignment of indexes to physical chemistry journal articles.

The two major components of AIMS are a natural language processing

(NLP) component and an index generation (IG) component. We provide an

overview of what each of these components does and how it works. We

also present the results of a recent evaluation of our system in terms

of recall and precision. The recall rate is the proportion of the

‘correct’ indexes (i.e. those produced by human document

analysts) generated by AIMS. The precision rate is the proportion of

the generated indexes that is correct. Finally, we describe some of

the future work planned for this project.
CONGRUENCY BETWEEN DEPRESSOGENIC SCHEMAS AND LIFE EVENTS FOR THE PREDICTION OF DEPRESSIVE RELAPSE IN REMITTED OLDER PATIENTS
Authors: Voyer Marléne , Cappeliez Philippe
Published: July 2002

Activation of a depressogenic schema by a negative life event is said to be more likely when the life event corresponds to the same domain of vulnerability (congruency hypothesis). Specifically, this refers to a negative interpersonal event for the sociotropy/dependency schema, and an obstacle or a failure in achieving a goal for the autonomy/accomplishment or self-criticism schema. This study examines the congruency hypothesis for the prediction of relapse. Older patients were followed for 6 months after remission from major depression. Life events were rated as interpersonal or autonomous in nature. Their subjective impact on social relations and on autonomous functioning was also assessed. Congruency between dependency schema and interpersonal events, but only when the subjective impact of event was taken into consideration, predicted relapse. Non-congruency between an autonomous schema and an event rated as impacting the social domain also predicted relapse. However, in both analyses of dependency and autonomy schemas, impact of event on social relations on its own predicted relapse. These findings support the cognitive vulnerability theory of depressive relapse, underlining the importance of considering how the person views the influence of life events and the determining impact of stressful life events on social relations.
Improvement or simply practice? The effects of twenty repeated
assessments on people with and without brain injury
Authors: WILSON BARBARA A. , WATSON PETER C. , BADDELEY ALAN D. , EMSLIE HAZEL , EVANS JONATHAN J.
Published: July 2002

Measuring recovery of function may mean testing
the same individual many times, a procedure that is inevitably
open to improvement due to learning on the specific tests
rather than recovery per se. This is particularly
likely to be an issue with measures of memory performance.
We therefore studied the performance of normal and brain-injured
people across 20 successive test sessions on measures of
orientation, simple reaction time, forward and backward
digit span, visual and verbal recognition, word list learning
and forgetting, and on three semantic memory measures,
namely, letter and category fluency and speed of semantic
processing. Differences in overall performances between
the two groups occurred for all tests other than orientation,
digit span forward, and simple reaction time, although
the tests differed in their degree of sensitivity. The
tests varied in the presence or absence of practice effects
and in the extent to which these differed between the two
groups. Data are presented that should allow investigators
to select measures that are likely to optimize sensitivity
while minimizing possible confounding due to practice effects.
(JINS, 2000, 6, 469–479.)
Bidirectional child–family influences on outcomes of
traumatic brain injury in children
Authors: TAYLOR H. GERRY , YEATES KEITH OWEN , WADE SHARI L. , DROTAR DENNIS , STANCIN TERRY , BURANT CHRISTOPHER
Published: July 2002

Child behavior problems, injury-related family burden, and
parent psychological distress were assessed longitudinally over
the first year post injury in 40 children with severe traumatic
brain injury (TBI), 52 with moderate TBI, and 55 with orthopedic
injuries not involving brain insult. Parents rated children's
preinjury behavior soon after injury. Postinjury child behavior
and family outcomes were assessed at 6- and 12-month follow-ups.
Findings from path analysis revealed both direct and indirect
effects of TBI on child behavior and family outcomes, as well
as cross-lagged child-family associations. Higher parent distress
at 6 months predicted more child behavior problems at 12 months,
controlling for earlier behavior problems; and more behavior
problems at 6 months predicted poorer family outcomes at 12
months, controlling for earlier family outcomes. Support for
bidirectional influences is tentative given that limited sample
size precluded use of structural equation modeling. The findings
nevertheless provide impetus for considering the influences
of person-environment interactions on outcomes of TBI.
(JINS, 2001, 7, 755–767.)
Farm-level benefits to investments for mitigating land degradation: empirical evidence from Ethiopia
Authors: Shiferaw Bekele , Holden Stein T.
Published: July 2002

Resource conservation programs have often been launched without careful evaluation of farmers' intertemporal tradeoffs in undertaking conservation investments. Such investments often have long pay back periods and reduce short-term household incomes. The critical question is whether long-term benefits would be sufficient to compensate farmers' immediate costs. Lack of empirical data on crop responses to soil erosion has hindered policy-relevant research. This study uses empirical data from the Ethiopian highlands to estimate the damage from soil erosion and evaluate the profitability of proposed conservation investments. A farm-level model is developed to study economic incentives to implement proposed conservation methods. Results show that incentives to invest in conservation practices are very low except for low cost methods like grass strips. The yield penalty due to area loss and high investment costs contribute to this. Policies focusing on minimizing the area loss effect and subsidizing the initial investment costs are shown to improve farmers' incentives to conserve the soil. A preferred policy option in the short-term is supporting low cost technologies that provide short-term benefits to poor farmers.