bluuebunny/crossref_metadata_2025 huggingface dataset:
AN INTRODUCTION TO ECONOMETRIC THEORY
Authors: Linton Oliver B.
Published: July 2002

This book is a modern introduction to measure theoretic
probability and statistical inference well targeted for
graduate students in econometrics at top institutions.
It would make an excellent textbook for first year graduate
students who intend to specialize in econometrics or who
have an advanced mathematical background, and it would
also be a useful part of any graduate econometrics course.
It is concise and intensely focused on the key conceptual
points, thus counteracting the tendency toward long-windedness
apparent in some recent econometric texts. Nevertheless,
it provides many valuable insights into difficult material.
In particular, the discussions of sigma fields and conditional
expectation given a sigma field are very helpful. The coverage
of multivariate concepts alongside univariate ones is particularly
useful to econometricians and something that is missing
from most comparable statistical texts. The author has
a mature attitude to proof, providing complete and illuminating
proofs of some results but making liberal use of simplifications
provided by special cases, for example in Theorems 4.1
and 4.5 and Section 5.2.2, to shorten and focus the arguments.
The proofs themselves are very clear and well presented.
Carefully chosen diagrams are given throughout the book
that nicely illustrate many of the key concepts. In addition,
each chapter contains a long list of problems of varying
complexity, which will be useful to instructors.
Resin-collecting bees (Apidae) on Clusia palmicida (Clusiaceae) in a riparian forest in Brazil
Authors: GONÇALVES-ALVIM SILMARY DE JESUS
Published: July 2002

Primary flower resources to bees, i.e. those that satisfy basic needs, such as
feeding and reproduction (Faegri & van der Pijl 1979), include pollen, nectar,
oil, resin and gums. Resins are used in nest construction as a waterproof and
structural material (Simpson & Neff 1981). It is also excellent antimicrobial
compound, and a sticky defence against ant attacks (Armbruster 1984, Dressler
1982, Lokvam & Braddock 1999, Michener 1990, Roubik 1989, Sakagami et
al. 1989). Plant species with flowers which produce terpenoid resins are rare
(Armbruster & Webster 1979). Clusia L. (Clusiaceae), Clusiella Planch. &
Triana (Clusiaceae), and Dalechampia L. (Euphorbiaceae) are the only known
plants that secrete resins from floral structures (Armbruster 1984,
Armbruster & Webster 1979, Bittrich & Amaral 1996). Although
resin-producing plants provide an essential resource for a large number of
bees in tropical communities, there are few studies about resin-collecting
bees on Clusia spp. Skutch (1971) was the first to report visits on
Clusia by stingless bees to collect floral resin. Other reports
include observations on C. odorata Seem. (Croat 1978, Ramirez &
Gomez 1978), C. alata Pl. & Tr. (Ramirez & Gomez 1978), and
C. nemorosa G. F. W. Meyer (Armbruster 1984, Bittrich & Amaral
1996, Lopes & Machado 1998, Mesquita & Fransciscon 1995). Recently, Bittrich
& Amaral (1996, 1997) have described the flower morphology and pollination biology
of other Clusia species from Central America and Venezuela.
Vagile but inbred: patterns of inbreeding and the genetic structure within populations of the monsoon rain forest tree Syzygium nervosum (Myrtaceae) in northern Australia
Authors: Shapcott Alison
Published: July 2002

Patterns of gene flow within 21 northern Australian populations of Syzygium nervosum a dominant, mass-flowering, monsoon rain forest canopy tree were investigated using 10 isozyme loci. S. nervosum was found to have relatively high genetic diversity within populations (He = 0.307, AP = 3.7, P = 65) but also to have significantly lower frequencies of heterozygotes than expected (Ho = 0.126) and high allelic fixation (F = 0.512). Heterozygosity and allelic fixation were not correlated with measures of genetic diversity within populations, nor were they correlated with rain forest patch size, plant size or population isolation. Within populations, trees, of the same genotype (at each loci tested) were significantly clumped at short distances (c. 20 m), whereas trees of unlike genotypes were negatively associated. S. nervosum trees however, were not clonal in origin and had unique multilocus genotypes. The results suggest that the high levels of homozygosity recorded are the result of restricted pollination, primarily among flowers within individual trees or among closely related neighbouring trees, rather than rectricted seed dispersal. High homozygosity, the large fruit crop produced by trees of this species and the lack of association between heterozygosity and plant size, indicate that, S. nervosum is self-compatible, its fecundity does not appear to be impaired by inbreeding depression.
Patterns of seedling survival in the tropical African tree Milicia excelsa
Authors: Nichols J. Doland , Agyeman Victor K. , Agurgo Francis Balfour , Wagner Michael R. , Cobbinah Joseph R.
Published: July 2002

The spatial patterns of canopy tree and seedling life stages in the African Tropical Tree Milicia excelsa were examined to test the Janzen–Connell hypothesis (escape hypothesis). The Janzen–Connell hypothesis states that the mortality of seeds and seedlings is highest near the adult tree and declines with distance away from the adult tree of the same species. This hypothesis argues that this effect is partially responsible for maintaining the high tree species diversity of tropical forests. Solar radiation and fruit dispersal were investigated as possible explanations of observed patterns in seedling distribution. Milicia excelsa trees ≥30 cm DBH were found to be randomly dispersed and occurred at a density of ≤1 ha. Milicia excelsa seedlings were located in small clumps between parent trees and up to 150 m from parents at a mean density of 65 seedlings ha−1. Fruits were in abundance (>9000 on the ground) beneath female trees. Light levels at locations of natural seedlings ranged from 2–29% of full irradiance. Planted seedlings did not suffer greater mortality closer to adult conspecifics, and survived at light levels between 2–37% of full irradiance. Phytolyma spp., gall-forming psyllids which cause high mortality in Milicia seedlings in large openings and plantations, were not observed on any natural or planted seedlings, although galls were present in the crowns of dominant trees.
Images of the poor in an official survey of Osaka, 1923–1926
Authors: TAMAI KINGO
Published: July 2002

Before the Second World War, Osaka was called the Manchester of the
East, because its industries, such as cotton spinning and metal work,
played such an important role in the national economy. Osaka had also
been a primary commercial centre of the country since the seventeenth
century. It is, therefore, no exaggeration to say that Osaka was the centre
of Japanese capitalism, and it was during the Taisho era, 1912–1926, that
Osaka was most prosperous. In those days there was unceasing
immigration to Osaka, particularly into the urban area, in order to find
employment. The migrants came primarily from rural areas, plus an
increasing number from Korea. Under such circumstances, acute social
problems emerged, in particular slums, unemployment and poverty.

During the Taisho period, the Osaka authorities were not unaware of
the problem of poverty. First, the local authorities began to recognize the
necessity of a municipal social policy and so they reorganized the
administration in order to attack poverty. With this reorganization, a new
department was formed to deal with all aspects of the social welfare of the
inhabitants. Secondly, they actively carried out and published social
surveys of urban poverty. From the information thus obtained, a relief
system was established, consisting, for example, of social work and public
assistance. Thirdly, urban officials accepted the responsibility of coping
with urban poverty and actually made efforts to tackle it. They tried to
define the meaning of poverty and the attitude of the local authorities
towards poverty changed completely from that which had obtained in any
previous period. It was in this era that the actual living and working
conditions of the urban poor became apparent to the authorities and
practical measures were taken to ameliorate poverty. For these reasons,
Osaka provides us with an interesting case study.

The focus of this article is on the relationship between poverty and
family formation in Osaka, including not only the circumstances of the
urban poor but also the factors influencing the attitudes of the local
authorities, who recognized the importance of the relationship between
urban poverty and family formation, and the nature of the relief system
they organized. Before going into detail concerning Osaka's poverty
problems between 1912 and 1926, however, it is necessary to examine the
set of circumstances which, one might argue, were critical in prompting
Osaka to launch a social work programme.
The First Autonomous Agents Conference
Authors: JOHNSON W. LEWIS , HAYES-ROTH BARBARA
Published: July 2002

The First International Conference on Autonomous Agents brought together researchers concerned with implementing systems that perceive and act in dynamic, unpredictable environments, that coordinate interoperation among complementary component capabilities, and that perform significant jobs with a high degree of autonomy.
SOME CONJECTURED UNIFORMLY OPTIMAL RELIABLE NETWORKS
Authors: Ath Yontha , Sobel Milton
Published: July 2002

We consider all-terminal reliability, one of the
more popular models in the field of network reliability.
A graph with n nodes and e edges, where
the nodes are perfectly reliable and the edges survive
independently with equal probability p, is said
to be a uniformly optimally reliable graph if it has for
all values of p (0 ≤ p ≤ 1) an
equal or higher reliability among all graphs with the same
number of nodes and edges. Boesch et al. [4]
verified the existence of uniformly optimally reliable
graphs for e = n − 1, e =
n, e = n + 1, and e =
n + 2; he has also given a conjecture for e
= n + 3. Wang [8] proved this conjecture.
In this article, we present four new infinite families of
graphs that we conjecture to be uniformly optimal.
TRANSFERABILITY AND PRODUCTIVITY OF L1 RULES IN CATALAN-ENGLISH
INTERLANGUAGE
Authors: Cebrian Juli
Published: July 2002

This paper examines the interference of L1 neutralization rules in the acquisition of a marked
L2 phonological feature. More specifically, it presents results from a study of the acquisition of
the voicing contrast in English word-final obstruents by native speakers of Catalan. The voicing
contrast in final position in Catalan is neutralized by voicing or devoicing rules, depending on
the environment. The results of an experiment testing the production of target final obstruents in
different environments indicate a very high incidence of devoicing, which confirms the
prevalence of final devoicing in second language acquisition and points to the joint effect of
transfer and universal tendencies. In contrast with devoicing, the results reveal a more limited
effect of the L1 voicing rules. It is argued that this difference is due to an effect of word integrity
in the interlanguage that restricts the domain of application of the transferred rules.
GENDER AS SOCIAL PRACTICE
Authors: Ehrlich Susan
Published: July 2002

This paper reviews current research on language and gender and discusses the
implications of such work for gender-based research in second language acquisition. Recent
work in sociolinguistics, generally, and language and gender research, more specifically, has
rejected categorical and fixed notions of social identities in favor of more constructivist and
dynamic ones. Thus, in this paper I elaborate a conception of gender that has not generally
informed research in the field of second language acquisition, and point to more recent work in
the field that theorizes and investigates gender as a construct shaped by historical, cultural,
social, and interactional factors.
LANGUAGE AND HUMAN BEHAVIOR.Derek Bickerton. Seattle:
University of Washington Press, 1995. Pp. 180. $24.95 cloth, $14.95 paper.
Authors: McWhorter John
Published: July 2002

Many will question Bickerton's claim that only humans are capable of mental
engagement with anything but the immediate present. However, the heart of his
argument—that language did not evolve as a development from high intelligence but is
instead what allowed that intelligence to develop at all—is undeniably compelling. Under
this conception, the emergence of language, not just intelligence, was what allowed humans to
conquer the world. In support, Bickerton notes that the appearance of modern civilization was
preceded by eons by cultural stasis during which hominid brains were nevertheless increasing
vastly in size, which suggests that something besides mere brain power created modern man. He
also notes that if human-like intelligence allowed world domination, then at least some animals
should by now have developed it, even without language. Instead, only humans can profoundly
alter their surroundings, which suggests that language, the trait most unequivocally unique to
humans, is indeed the key to our hegemony. Bickerton even equates language and thought,
arguing that their foundation upon the same syntax leaves no motivation to separate them, and
considers both to evidence a layer of abstract representation unique to humans. In turn, he
proposes that this layer is able to “observe” the lower layer, thus creating
“consciousness.” The uniqueness of consciousness to humans is thus explained by
its roots in a layer of representation unique to humans.
Lexical and grammatical development: a behavioural genetic perspective
Authors: DALE PHILIP S. , DIONNE GINETTE , ELEY THALIA C. , PLOMIN ROBERT
Published: July 2002

The relation of lexical and grammatical knowledge is at the core of many
controversies in linguistics and psycholinguistics. Recent empirical
findings that the two are highly correlated in early language development
have further energized the theoretical debate. Behavioural genetics
provides an illuminating new tool to explore this question, by addressing
the question of whether the empirical correlation simply reflects the fact
that environments which facilitate one aspect of language growth also
facilitate the other, or whether the same underlying acquisition
mechanisms, influenced by the same genes, are responsible for the
correlation. We explored this issue in a study of 2898 pairs of two-year-old
twins born in England and Wales. Language development was
assessed by their parents using an adapted version of the MacArthur
Communicative Development Inventory which assesses vocabulary and
grammar. Moderate heritabilities were found for both. As in previous
studies, measures of vocabulary and sentence complexity were substantially
correlated (r = 0·66). Behaviour-genetic modelling of the
relation of vocabulary and grammar produced an estimated value of 0·61
for the genetic correlation, a measure of the overlap of the genetic effects
that contribute to the two aspects of language development. In contrast,
a measure of nonverbal cognitive development, the PARCA, was only
weakly correlated at both the phenotypic level and at the level of genetic
correlations with the language measures. Thus, although the distinction
between verbal and nonverbal skills has a genetic basis underlying the
phenotypic dissociation, there is little evidence either genetically or
phenotypically for a dissociation between vocabulary and grammar
within language.
The Contrast Theory of negative input
Authors: SAXTON MATTHEW
Published: July 2002

Beliefs about whether or not children receive corrective input
for

grammatical errors depend crucially on how one defines the concept of

correction. Arguably, previous conceptualizations do not provide a

viable basis for empirical research (Gold, 1967; Brown & Hanlon, 1970;

Hirsh-Pasek, Treiman & Schneiderman, 1984). Within the Contrast

Theory of negative input, an alternative definition of negative evidence

is offered, based on the idea that the unique discourse structure created

in the juxtaposition of child error and adult correct form can reveal to

the child the contrast, or conflict, between the two forms, and hence

provide a basis for rejecting the erroneous form. A within-subjects

experimental design was implemented for 36 children (mean age 5;0), in

order to compare the immediate effects of negative evidence with those

of positive input, on the acquisition of six novel irregular past tense

forms. Children reproduced the correct irregular model more often, and

persisted with fewer errors, following negative evidence rather than

positive input.
Preschoolers' communication during scripted interactions
Authors: SHORT-MEYERSON KATHERINE J. , ABBEDUTO LEONARD J.
Published: July 2002

The communicative interactions of 15 dyads of four- to five-year-olds
during pretend play involving routine, or scripted, events were investigated
as a function of the children's knowledge of the scripts. Measures
of the quantity and quality of interaction and the strategies that the
children used to establish mutual knowledge (i.e. assess and adapt to
their discourse partner's level of expertise), which is essential to good
communication, were examined. Each dyad participated in a MATCHED
condition (both members had extensive knowledge of the script) and a
MISMATCHED condition (one member had extensive script knowledge and
the other did not). Shared script knowledge facilitated communicative
interactions, as indicated by more topic maintenance and fewer requests
for clarification in the matched condition than in the mismatched
condition. The children attempted to establish mutual knowledge more
frequently in the mismatched condition than in the matched condition
and, moreover, mutual knowledge establishment was related to the
children's communicative effectiveness.
Relative clauses in French children's narrative texts
Authors: JISA HARRIET , KERN SOPHIE
Published: July 2002

This study investigates the use of relative clauses in French children's

narrative monologues. Narrative texts were collected from French-speaking monolinguals in four age groups (five, seven, ten years and
adults). Twenty subjects from each group were asked to tell a story
based on a picture book consisting of twenty-four images without text
(Frog, Where are you?). Relative constructions were coded following
the
categories defined by Dasinger & Toupin (1994) into two main functional

classes: general discourse and narrative functions. The results
show that the use of relative clauses in general discourse functions
precedes their use in more specific narrative functions. An analysis of

textual connectivity (Berman & Slobin, 1994) in one episode reveals
that
children and adults differ in their choice of preferred structures. The

results also show that children use fewer transitive predicates in relative

clauses than do adults. Transitive verbs are essential for advancing the

narrative plot (Hopper & Thompson, 1980). While subject relative
clauses are acquired early and used frequently, the development of their

multifunctional use in diverse narrative functions extends well beyond

childhood.
The acquisition of mood selection in
Spanish relative clauses
Authors: PÉREZ-LEROUX ANA TERESA
Published: July 2002

Although children acquire Spanish subjunctive morphology early
in the
process of language acquisition, they only master mood selection in a
staged process that lasts for several years. This paper examines the
possibility that the acquisition of subjunctive mood selection in particular

syntactic contexts is constrained by cognitive development in the
area of representational theory of mind. Acquisition of the epistemic
aspects of the semantics of subjunctive are shown to be associated with

the understanding of false beliefs, a landmark development in children's

cognition. Twenty-two Spanish speaking children between the ages of
3;5 and 6;11 participated in an elicited production study designed to
test whether children's ability to produce subjunctive relative clauses

was related to their ability to pass a false belief task. Results indicate
a
strong correlation between children's ability to use the subjunctive

mood in relative clauses and their capacity for understanding false
beliefs.
Chinese children's understanding of false beliefs: the
role of language
Authors: LEE KANG , OLSON DAVID R. , TORRANCE NANCY
Published: July 2002

The present study investigated the universality of the early development

of young children's understanding and representation of false beliefs,

and specifically, the effect of language on Chinese-speaking children's

performance in false belief tasks under three between-subjects conditions.

The three conditions differed only in the belief verb that was
used in probe questions regarding one's own or another person's
beliefs,
namely the Chinese verbs, xiang, yiwei, and
dang. While the three words
are all appropriate to false beliefs, they have different connotations

regarding the likelihood of a belief being false, with xiang being
more
neutral than either yiwei or dang.
Experiment i involved thirty-five
Chinese-speaking adults who responded to false belief tasks to be used

in Experiment 2 in order both to establish an adult comparison and to
obtain empirical evidence regarding how Chinese-speaking adults use
the three belief verbs to describe different false belief situations. In

Experiment 2, 188 three-, four-, and five-year-old Chinese-speaking
children participated in three false belief tasks. They were asked to
report about an individual's false belief when either
xiang, yiwei, or dang
was used in the probe question. Results revealed a rapid developmental

pattern in Chinese-speaking children's understanding of false belief,

which is similar to that found with Western children. In addition,
children performed significantly better when yiwei and dang, which
connote that the belief referred to may be false, were used in belief
questions than when xiang, the more neutral verb, was used. This

finding suggests an important role of language in assessing children's

understanding of belief and false belief.
Grammatical and caregiver cues in early sentence
comprehension
Authors: SHADY MICHELE , GERKEN LOUANN
Published: July 2002

In order to begin to learn a language, young children must be able
to
locate and distinguish linguistic units in the speech they hear. A number

of cues in the speech stream may aid them in this task. Some cues, such

as frequently occurring grammatical morphemes and prosodic changes
at linguistic boundaries are inherent in the language. Other cues, such
as
short utterance length and placement of key words in utterance-final
position, are not integral to the grammar of the language but are
characteristically provided by caregivers. Although previous studies
suggest that even infants are sensitive to many of these cues, it is not

clear that young listeners actually use them in assigning structure to

sentences. The experiments reported here asked whether 60 children
aged 2;0 to 2;2 used grammatical and caregiver cues in sentence
comprehension and how different types of cues interacted. Two findings

are of note: children used all of the cues tested, and the presence of
one
type of cue did not diminish use of another.
Absolutely continuous spectrum of Dirac systems with potentials
infinite at infinity
Authors: SCHMIDT KARL MICHAEL
Published: July 2002

It is shown that the spectrum of a one-dimensional Dirac operator
with a potential q tending to infinity at infinity, and such that
the positive variation of 1/q is
bounded, covers the whole real line and is purely absolutely
continuous. An example
is given to show that in general, pure absolute continuity is lost
if the condition on
the positive variation is dropped. The appendix contains a direct proof
for the special case of subordinacy theory used.
The Pervasiveness of the Commonplace: The Historian and Amateur Theatre
Authors: Cochrane Claire
Published: July 2002

Amateur theatre constitutes a largely unexplored narrative within the dominant histories of British theatre that traditionally foreground professional practice. A consequence of advanced capitalism has been an increasing emphasis on professionalism in all sectors of society that constructs the amateur as incompetent and expects guaranteed rewards for professional expertise. Statistically, however, amateur theatre has represented a major experience of performance for a significant proportion of the population especially those of the small nations that have been subsumed within the British nation-state. Much of today's state-funded theatre that ostracizes the amateur, has its roots in early twentieth-century amateur/professional collaborations and grassroots activity in the inter-war years. An examination of the ideological basis of aesthetic value judgements which are, in fact, socially constructed judgements of taste, raises issues about both the cultural value of performance and the responsibility of the historian to the experience of the past.
AIS Adding New Quality to VTS Systems
Authors: Harre Ingo
Published: July 2002

This paper was presented at ETT99/SATNAV99 Conference, held by DGON/NIN in
Potsdam, Germany on 9th November 1999.

In the foreseeable future, Automatic Identification Systems (AIS) will be installed aboard all
sea-going ships larger than 300 g.r.t. These new devices broadcast data at regular and short
intervals, by means of which the ship can be identified and tracked. Further data can be
transmitted to provide additional information on the ship's motion, navigational status,
intended voyage and cargo. The transmissions can be received by every interested party
having an appropriate receiver both at sea and ashore. With these capabilities, AIS adds a
new information quality to maritime traffic, which is relevant not only for ship/ship but also
for VTS/ship interaction. This paper describes the genesis of the new systems and their
operational and technical aspects. It continues with a discussion of their standard and
extended applications and their – so far – unexploited potential. Where relevant, the results
of R&D work and practical tests are mentioned.
Navigation and Electro-Optic Sensor
Integration Technology for Fusion of
Imagery and Digital Mapping Products
Authors: Brown Alison , Olson Paul
Published: July 2002

Several military and commercial platforms are currently installing GPS and inertial
navigation sensors concurrently with the introduction of high-quality visual capabilities and
digital mapping/imagery databases. This enables autonomous geo-registration of sensor
imagery using GPS/inertial position and attitude data, and also permits data from digital
mapping products to be overlaid automatically on the sensor imagery. This paper describes
the system architecture for a Navigation/Electro-Optic Sensor Integration Technology
(NEOSIT) software application. The design is highly modular and based on commercial off-the-shelf (COTS) tools to facilitate integration with sensors, navigation and digital data
sources already installed on different host platforms.
Forest products and household economy: a case study from Mudumalai Wildlife Sanctuary, Southern India
Authors: HEGDE R. , ENTERS T.
Published: July 2002

Traditional communities living at forest margins use forest resources in various ways. Understanding the resource-use patterns of such communities provides a basis for seeking the participation of such communities in forest conservation. The present study undertaken in the Mudumalai Wildlife Sanctuary and the adjoining Sigur Plateau in the state of Tamil Nadu, India, addressed the importance of forests in the household economy of indigenous communities. Its main objective was to quantify the forest dependence of local people, and assess to what extent restrictive biodiversity conservation strategies would affect their livelihoods. These questions help in understanding the stake of the people in forest conservation strategies. Economic activities of the households were investigated in eight selected villages, four of which (proximal villages) had access to reserve forest areas where collection of forest products was allowed and were also located close to markets that provided opportunities to sell forest products. The remaining four villages (distal villages) were close to the Wildlife Sanctuary where the collection of forest products was not allowed and there was no access to organized markets. A total of 132 households were surveyed. The households both in proximal and distal villages were classified into three distinct income groups namely ‘low’, ‘medium’ and ‘high’, based on their gross annual income. Use of forest resources in Mudumalai was found to be influenced by multiple factors. In terms of livelihood of the traditional communities, livestock rearing and collection of non-wood forest products (NWFPs) were very important, the latter both for cash income and subsistence use. Peripheral communities used the forest resources in a varied fashion, with NWFPs contributing differently to different income groups. Where there was no restriction on forest use, higher income groups used the resources more heavily than lower income groups, and hence would suffer most from any restriction on forest use. People's reliance on forests evidently declined with increased level both of education and of opportunities in non-forestry vocations. Forests were still very important to the household economy of the local people both in terms of food security and cash income.
The dynamics of avicultural markets
Authors: Robinson Jennifer M.
Published: July 2002

Trade restrictions stemming from the Convention on International Trade in Endangered Species (CITES) have created a situation in which rare and attractive bird species command high prices on international pet markets. Most of these species are of tropical or subtropical origin, and many are amenable to captive breeding. Hence, the possibility of exporting birds under CITES provisions for the export of captive-raised animals is under debate in many countries around the world. If export bans are replaced by systems of export permits, the economics of avicultural markets will govern the magnitude, timing, and nature of the impacts of the bird trade. Avicultural economics, however, is little studied, and the long-term economic viabilities of exotic pet markets are poorly understood. In order to elucidate these, a dynamic model of an avicultural market was constructed, based on descriptive information. Model simulations showed that the high prices commanded by sought-after bird species tended to bring about oversupply and rapid price decline. Short-lived, fecund species produced a rapid, sharp pulse of oversupply; longer-lived species produced more persistent but less acute conditions of oversupply. The present high prices for protected bird species may be regarded as a potential source of windfall profits, or as a factor that might be manipulated to discourage the poaching and smuggling of wild birds. If export-oriented aviculture is considered as a component of strategies for diversification of agriculture and promotion of sustainable development, it is important that decision-makers factor in the likelihood of significant declines in bird prices and that they consider the risk of accidental species introductions that is inherent in holding large exotic-bird populations.
An assessment of social impacts of national parks on communities in Quebec, Canada
Authors: FORTIN MARIE-JOSE , GAGNON CHRISTIANE
Published: July 2002

Numerous national parks have been established worldwide to protect nature, but this has not been without social consequences for neighbouring communities. Since the social and economic vitality of adjacent communities is being recognized more and more as indispensable for the success of conservation objectives, the quality of park-community relations has become a critical issue. A four-year investigation into the social impacts engendered by two national parks situated in the Saguenay region of Quebec (Canada) was conducted, according to a social impact assessment method. Several impacts and changes were identified on resource management, on the local economy, on the tourist industry, on involvement and participation of local actors and on the social organization of the neighbouring communities. The significance of these impacts varied according to the community and the actors involved. The results of the present research point to the determining role of the government in general, and of the park management in particular, in the process of local community development. In this regard, recommendations are addressed to local communities to improve their partnership with national parks.
SEED-Config: A case-based reasoning system for conceptual
building design
Authors: RIVARD HUGUES , FENVES STEVEN J.
Published: July 2002

A case-based design functionality is a natural and
intuitive addition to a design tool that can augment
human capabilities and help designers remember and retrieve
appropriate cases. SEED-Config, a design environment for
conceptual building design, was developed to incorporate
a case-based reasoning functionality to provide designers
with initial potential solutions. The case representation
in SEED-Config is the BENT information model, which records
design knowledge, supports the hierarchical decomposition
of design cases, offers multiple views, and encapsulates
the outcome of the design in addition to the problem specification
and the design solution. The case library was implemented
in an object-oriented database management system to accumulate
cases automatically and to provide efficient query facilities.
The case retrieval aspect of SEED-Config offers three different
methods to find the most useful cases stored in the case
library: task-based, lineage-based, and customized. Case
retrieval responds to the exploratory nature of the design
process and supports versatile case retrieval by providing
multiple paths to each case. The case adaptation aspect,
which adjusts the selected case to the new problem to provide
a complete solution, uses an adaptation method called derivational
replay. The case-based design capabilities are completely
integrated within the design environment from which the
cases originate.
An artificial neural network for resource leveling problems
Authors: KARTAM NABIL , TONGTHONG TANIT
Published: July 2002

A new methodology for solving resource leveling
problems is introduced using Artificial Neural Networks
(ANN). This paper describes a new efficient and robust
approach which is unique to those utilized by traditional
heuristic and optimization resource leveling techniques.
The Resource Leveling Artificial Neural Network (RLANN)
exploits advantages of both Hopfield networks and competition-based
artificial neural networks. The universal scheme of the
RLANN is applicable to construction project networks produced
with Critical Path Method (CPM), in forms of either arrow
or precedence diagrams. The scheme is comprised of two
layers, an input and a competition layer, of artificial
node matrices fully connected by links. Solving mechanisms
inside the RLANN are based on an equation of motion and
a competition strategy that control the level of daily
resource usage. While the equation of motion governs activities
to be shifted within schedule constraints, the competition
process finds the best positions for the activities to
achieve optimum results. The approach is simple and can
be implemented on either a personal computer or a parallel
processing device. The solutions produced are comparable
to, or better than, those generated by other heuristic
or optimization techniques. This paper describes the development
of the RLANN, its solving mechanisms, and its uses in construction
resource leveling problems. The comparison of the result
of the RLANN to those of other traditional techniques is
also included. The conclusions highlight the applicability
of this model to other civil engineering problems.
Comparative utility of restriction fragment length polymorphism analysis and gene sequencing to the molecular epidemiological investigation of a viral outbreak
Authors: GOLDBERG T. L. , WEIGEL R. M. , HAHN E. C. , SCHERBA G.
Published: July 2002

Restriction fragment length polymorphism (RFLP) analysis and partial-genome DNA sequencing are commonly used to infer genetic relationships among pathogens. This study compares the application of both techniques to the analysis of 16 pseudorabies virus isolates collected during a 1989 outbreak. Genetic distances derived from RFLP and DNA sequence data were not significantly correlated with geographic distances between farms from which isolates were collected. RFLP-based genetic distance was, however, strongly correlated with temporal distance between isolates (days separating time of isolation). Sequence-based genetic distance was significantly correlated with temporal distance only when synonymous changes (nucleotide changes not leading to amino acid changes) were considered separately. Conversely, non-synonymous changes were correlated with the host species of origin of the viral isolate. These results indicate that selectively-neutral genetic changes most accurately reflect historical relationships, but that non-neutral changes most accurately reflect the biological environment of the viral isolate (e.g. host immune system).
Sexually transmitted diseases among foreigners in Italy
Authors: SULIGOI B. , GIULIANI M. , THE MIGRATION MEDICINE STUDY GROUP
Published: July 2002

A sentinel surveillance system for the control of sexually transmitted

diseases (STD) among

foreigners was developed in Italy in 1991. From January 1991 to June 1995,

4030 foreigners

with a new STD episode were reported. More than one-third of them were

North-Africans.

The most frequent STDs were non-specific urethritis and genital warts among

men, and non-specific vaginitis and latent syphilis among women. The overall

HIV prevalence was 5%, with

large differences in rates in people from different continents. Very high

HIV-positivity rates

were observed among homosexuals and homosexual IDUs from Central–South

America, with

39·1% and 77·8% seropositive individuals respectively.

These data stress the need for increased knowledge of both the spread

of and risk factors for

STDs among immigrants. Particular attention should be paid to counselling

procedures focused

on the prevention of risk behaviours for acquiring STDs and HIV infection.
Middle ear effusion: rate and risk factors in Australian
children attending day care
Authors: SKULL S. A. , MORRIS P. S. , YONOVITZ A. , ATTEWELL R. G. , KRAUSE V. , LEACH A. J. , ANAND A. , SCOTT J. , REID S. , ROBERTS L. A.
Published: July 2002

There have been no previous longitudinal studies of otitis media conducted in non-Aboriginal
Australian children. This paper describes the rate and risk factors for middle ear effusion
(MEE) in children attending day care in Darwin, Australia. A prospective cohort study of 252
children under 4 years was conducted in 9 day care centres over 12 fortnights between 24
March and 15 September 1997. Tympanometry was conducted fortnightly and multivariate
analysis used to determine risk factors predicting MEE. The outcome of interest was the rate
of type B tympanograms per child detected in either ear at fortnightly examinations. After
adjusting for clustering by child, MEE was detected on average 4·4 times in 12 fortnights (37%
of all examinations conducted). Risk factors associated with presence of effusion were younger
age, a family history of ear infection, previous grommets (tympanostomy tubes), ethnicity and
the day care centre attended. A history of wheeze appeared protective. These effects were
modest (RR 0·57–1·70). Middle ear effusion is very common in children attending day care in
Darwin. This has clinical importance, since MEE during early childhood may affect optimal
hearing, learning and speech development. There is little scope for modification for many of
the risk factors for MEE predicted by this model. Further study of the day care environment is
warranted.
Nasopharyngeal colonization of infants in southern India with
Streptococcus pneumoniae
Authors: JEBARAJ R. , CHERIAN T. , RAGHUPATHY P. , BRAHMADATHAN K. N. , LALITHA M. K. , THOMAS K. , STEINHOFF M. C.
Published: July 2002

To investigate the dynamics of nasopharyngeal colonization with Streptococcus pneumoniae,
and to determine the prevalent serogroups/types (SGT) and their antimicrobial susceptibility,
we studied 100 infants attending our well-baby clinic. Nasopharyngeal swab specimens were
obtained at 6, 10, 14, 18 and 22 weeks and at 9 and 18 months of age and submitted for
culture, serotyping and antimicrobial susceptibility testing of S. pneumoniae. Colonization with
pneumococcus was seen on at least one occasion in 81 infants. The median age of acquisition
was 11 weeks and the median duration of carriage was 1·3 months. The common SGTs
identified were 6, 19, 14 and 15. SGT 1, which was a common invasive isolate in children in
our hospital during this period, was not isolated from these children. Sequential colonization
by 2, 3 or 4 SGTs was observed in 18, 5 and 2 children, respectively. Resistance to penicillin,
chloramphenicol, cotrimoxazole and erythromycin was observed in 0, 13 (6%) 11 (5%) and
5 (3%) isolates, respectively. There was a significant difference in susceptibility to
cotrimoxazole between colonizing and invasive isolates (5% vs. 40%, P<0·0001).
Sero-epidemiology of rubella in the urban population of Addis Ababa, Ethiopia
Authors: CUTTS F. T. , ABEBE A. , MESSELE T. , DEJENE A. , ENQUSELASSIE F. , NIGATU W. , NOKES D. J.
Published: July 2002

We conducted a community-based cluster sample survey of rubella sero-epidemiology in Addis
Ababa, Ethiopia in 1994. Among 4666 individuals for whom complete data were available,
rubella antibody prevalence was 91% (95% confidence interval: 90, 92). On multivariable
analysis, seroprevalence was lower among individuals who were resident in Addis Ababa for
1 year or less. Approx. 50% seroprevalence was attained by age 4 years, and the estimated
average age at infection was 5·2 years. The highest age-specific force of infection was estimated
to occur in 5- to 9-year-olds. The early age at infection corresponded with a low estimated
incidence of congenital rubella syndrome (CRS) of 0·3 per 1000 live births, equivalent to nine
cases of CRS in 1994. The predicted critical level of immunity for elimination of rubella via
vaccination was 85–91%, requiring 89–96% coverage with a vaccine of 95% effectiveness.
Unless very high coverage of rubella vaccine could be guaranteed, the introduction of
childhood vaccination could increase the incidence of CRS in Addis Ababa.
Is cytomegalovirus infection a co-factor in HIV-1 disease progression?
Authors: ROBAIN M. , BOUFASSA F. , HUBERT J. B. , DUSSAIX E. , SADEG K. , MEYER L.
Published: July 2002

The influence of cytomegalovirus (CMV) infection as a co-factor in HIV-1 disease progression
has mainly been studied in haemophiliacs and remains controversial. Based on the files of 1683
HIV-1-infected patients in the Seropositive Cohort (SEROCO) and Haemophiliacs Cohort
(HEMOCO) cohorts, we studied the role of CMV infection in progression to CD4+ cell counts
of less than 200 μl, AIDS onset and death, in various HIV exposure groups. Adjusted relative
risk (aRR) of progression to AIDS and to death was respectively 1·30 (P = 0·05) and 1·58
(P = 0·007). In the sexual exposure group the influence of CMV infection on the risk of
progression to AIDS was of borderline significance (aRR = 1·50; P = 0·07) and was more
marked on the risk of death (aRR = 2·00; P = 0·03). No such influence of CMV infection was
observed in the transfusion and intravenous drug use exposure groups. When we studied the
influence of CMV infection according to the stage of HIV disease, the main effect was on
progression from AIDS to death, probably because CMV disease is a late event. Sexual CMV
transmission and frequent re-exposure to CMV may explain why CMV infection emerged as an
important co-factor for HIV progression only in the sexual exposure group.
More on the Third Dialect of English: Linguistic constraints
on the use of three phonological variables in Pittsburgh
Authors: McElhinny Bonnie
Published: July 2002

Traditional dialect boundaries in the United States
have received renewed attention (Labov, 1991, 1994). Labov
outlined three dialects of English (the Northern Cities
Chain Shift, the Southern Chain Shift, and the Third Dialect),
the boundaries of which are defined by chain shifts in
the vowel system and roughly correspond to traditional
dialectal boundaries defined through the bundling of lexical
items (Kurath, 1949) and phonological isoglosses (Kurath
& McDavid, 1961). Other research has suggested that
the Third Dialect may be the most heterogeneous of these
dialects, with speakers in different areas displaying widely
disparate behaviors (see, e.g., Clarke, Elms, & Youssef,
1995; Di Paolo, 1988; Di Paolo & Faber, 1990; Labov,
1996; Moonwomon, 1987). The present article contributes
towards a richer picture of the Third Dialect by offering
the first systematic variationist analysis of speech in
Pittsburgh, with a particular focus on three phonological
processes: vocalization of /l/, laxing of /i/ before /l/,
and laxing of /u/ before /l/. I argue that Veatch's
(1991) model of English syllable structure provides a unified
account of these seemingly unrelated phonological changes
in Pittsburgh; the implications of this argument for further
research on Pittsburgh speech are also noted.
Adrenocortical activity in at-risk and normally developing adolescents: Individual differences
in salivary cortisol basal levels, diurnal variation, and responses to social challenges
Authors: KLIMES–DOUGAN BONNIE , HASTINGS PAUL D. , GRANGER DOUGLAS A. , USHER BARBARA A. , ZAHN–WAXLER CAROLYN
Published: July 2002

The purpose of this study was to examine adrenocortical activity (basal, diurnal variation, and
responses to social stressors) in adolescents at risk for psychopathology. Salivary cortisol levels
were examined in normally developing and at-risk youth with internalizing and externalizing
symptoms ranging from subclinical to clinical levels. Adolescents showed expected patterns of
diurnal variation, with high early morning cortisol levels and a pattern of decline throughout the
day. Females showed higher midday and late afternoon levels than males, and these patterns
interacted with risk status. Internalizing problems sometimes were associated with gradual rather
than steep declines in basal cortisol production. Both immediate and delayed cortisol reactivity to
a social performance stressor were associated with internalizing symptoms. There was no
evidence of relations between externalizing problems and underarousal of the
hypothalamic–pituitary–adrenal (HPA) system. These and other results suggest that
gender is an important moderating factor linking psychopathology, development, and context with
HPA axis functioning in adolescence.
EEG activation in 1-month-old infants of depressed mothers
Authors: JONES NANCY AARON , FIELD TIFFANY , FOX NATHAN A. , LUNDY BRENDA , DAVALOS MARISABEL
Published: July 2002

Previous research has documented differences in the pattern of EEG activation between

3-month-old infants of depressed mothers and infants of nondepressed mothers. In the present

study, EEG was recorded in even younger 1-month-old infants of depressed and nondepressed

mothers. The infants of depressed mothers exhibited greater relative right frontal EEG

asymmetry (due to reduced left frontal activation), and this pattern at 1 month was significantly

related to 3-month EEG asymmetry. Right frontal EEG asymmetry was also related to more

frequent negative facial expressions (sad and pre-cry faces) during the Brazelton exam. Finally,

the infants of depressed mothers showed more indeterminate sleep, were less active, and cried

less than infants of nondepressed mothers.