bluuebunny/crossref_metadata_2025 huggingface dataset:
Developmental approaches to substance use and abuse
Authors: CICCHETTI DANTE , LUTHAR SUNIYA S.
Published: July 2002

In 1996 the Institute of Medicine (IOM, 1996) issued a report on pathways to addiction.
Although focused on the use of illegal drugs, the recommendations of the committee are equally
applicable to more socially condoned, but still addictive, substances such as alcohol. The IOM
(1996) report articulated the types of research that would be needed to expand the understanding
of the etiology of drug use disorders, including the following: (a) multidisciplinary research to
investigate the combined effects of biological, psychosocial, and contextual factors as they relate
to the development of drug use, abuse, and dependence; (b) studies of sufficient duration to
enable follow-up of participants in determining the role of risk and protective factors related to
the transition from drug use to abuse to dependence; (c) research investigating the role of family
factors in the etiology of drug use and abuse; (d) examination of psychopathology as a precursor
to drug use and abuse in adolescents and adults; (e) studies of risk and protective factors related
to drug use and abuse, especially during discrete developmental stages; and (f) investigation of
childhood risk and protective factors that are associated with drug abuse and dependence. In
reflecting on these comprehensive goals, striking similarities emerge with respect to these
research foci and the field of developmental psychopathology (Cicchetti & Cohen, 1995;
Cicchetti & Toth, 1991). Specifically, the principles that guide inquiries conceptualized
within a developmental psychopathology framework can be applied toward the conduct of
studies designed to address the agenda generated by the IOM (1996) report on substance
abuse.
Marschner's villains, monomania, and the fantasy of deviance
Authors: MEYER STEPHEN
Published: July 2002

Marschner's villains occupy an important place in the history of operatic style, forming a bridge between characters such as Dourlinski or Pizarro and Wotan or the Dutchman. His villains may also be understood against the background of early nineteenth-century pathology, and particularly the syndrome of ‘monomania’. Marschner's music, which partially ‘heroicizes’ the villains in keeping with the contemporary rise of the sympathetic villain, parallels efforts to redefine the nature of madness. Marschner's operas could thus simultaneously construct and undermine the hegemony of bourgeois values, and become a vehicle through which composers, performers, and audiences could explore the contradiction between social/sexual order and the fantasy of deviance.
Coarsening in an integro-differential model of phase transitions
Authors: DUNCAN DUGALD B. , GRINFELD MICHAEL , STOLERIU IULIAN
Published: July 2002

Coarsening of solutions of the integro-differential equation

formula here

where Ω ⊂ ℝn, J(·) [ges ] 0, ε > 0 and
f(u) = u3 − u (or similar bistable nonlinear term), is
examined, and compared with results for the Allen–Cahn partial differential equation. Both
equations are used as models of solid phase transitions. In particular, it is shown that when
ε is small enough, solutions of this integro-differential equation do not coarsen, in contrast
to those of the Allen–Cahn equation. The special case J(·) ≡ 1 is explored in detail, giving
insight into the behaviour in the more general case J(·) [ges ] 0. Also, a numerical approximation
method is outlined and used on tests in both one- and two-space dimensions to verify and
illustrate the main result.
Analysis of the free boundary for the pricing of an American call option
Authors: šEVČOVIČ DANIEL
Published: July 2002

The purpose of this paper is to analyse the free boundary problem for the Black–Scholes
equation for pricing the American call option on stocks paying a continuous dividend. Using
the Fourier integral transformation method, we derive and analyse a nonlinear singular
integral equation determining the shape of the free boundary. Numerical experiments based
on this integral equation are also presented.
Boundary layers and domain decomposition for
radiative heat transfer and diffusion equations:
applications to glass manufacturing process
Authors: KLAR A. , SIEDOW N.
Published: July 2002

In this paper domain decomposition methods for
radiative transfer problems including
conductive heat transfer are treated. The paper focuses on semi-transparent
materials, like
glass, and the associated conditions at the interface between the materials.
Using asymptotic
analysis we derive conditions for the coupling of the radiative
transfer equations and a diffusion
approximation. Several test casts are treated and a problem appearing in
glass manufacturing
processes is computed. The results clearly show the advantages of a domain
decomposition
approach. Accuracy equivalent to the solution of the global radiative transfer
solution is
achieved, whereas computation time is strongly reduced.
Infiltration in porous media with dynamic capillary pressure: travelling waves
Authors: CUESTA C. , van DUIJN C. J. , HULSHOF J.
Published: July 2002

We consider a model for non-static groundwater flow where the saturation-pressure relation
is extended by a dynamic term. This approach, together with a convective term due to gravity,
results in a pseudo-parabolic Burgers type equation. We give a rigorous study of global
travelling-wave solutions, with emphasis on the role played by the dynamic term and the
appearance of fronts.
T-cell immunosenescence and its clinical relevance in man
Authors: Remarque Ed , Pawelec Graham
Published: July 2002

Scientific progress in human immunosenescence research is pointing increasingly towards the clinical importance of age-associated changes in immunity, although many areas remain controversial. For infectious disease, there is accumulating good empirical evidence, discussed in this review, that immunosenescence compromises protection in elderly people. This implies that an age-associated decreasing immunity results in increased incidence of those diseases that the immune system is designed to protect against, i.e. infectious diseases. This unsurprising conclusion suggests that preventing these infections using interventions designed to prevent or reverse immunosenescence could extend the period of life enjoyed in good health.
Sens, choix et subjonctif
Authors: Mailhac Jean-Pierre
Published: July 2002

Si l'on examine les études linguistiques et chapitres de grammaires consacrés au subjonctif français, ou des ouvrages généraux qui se réfèrent à ce mode, on découvre fréquemment un même principe qui conditionne l'analyse: une forme linguistique n'a de sens que s'il existe un ‘choix’. Le subjonctif n'aurait donc aucune signification là où il est obligatoire. Nous nous proposons ici, après un bref survol d'auteurs qui s'en inspirent, de soumettre ce principe à la critique, afin de démontrer qu'il recouvre de multiples confusions conceptuelles et entraîne des conséquences inacceptables pour l'explication du subjonctif, la morphosyntaxe et, plus généralement, la démarche du linguiste ainsi que les propriétés universelles postulées pour le langage.
St Ethelbert, King and Martyr: his cult and office in the West of England
Authors: CALDWELL JOHN
Published: July 2002

The music for the Office of St Ethelbert, king and martyr, survives uniquely in the thirteenth-century Hereford Noted Breviary. While some of the chants are contrafacta, others appear to be unique to this office and even in some cases to be influenced by the content of their texts, which are based on the vita of the sainted king by Gerald of Wales. The form in which the office was performed depended on its position in relation to the Easter Cycle (the feast fell on 20 May), and this in turn raises issues for the editing of such offices in modern times.
Response to “Abortion and Assent” by Rosamond
Rhodes (CQ Vol 8, No 4) and “Abortion, Disability, Assent,
and Consent” by Matti Häyry (CQ Vol 10, No 1)
Authors: Vehmas Simo
Published: July 2002

It is now a widely shared opinion in the Western countries
that a child's disability would probably place an unexpected
burden on her parents, a burden that the parents have not committed
themselves to dealing with. A child with a physical or mental
disability is not, so to speak, a part of the package the parents
ordered. This line of reasoning has recently been supported
by Rosamond Rhodes in her article “Abortion and
Assent.”
Every Death Is Different
Authors: FROM A PHYSICIAN AT A MAJOR MEDICAL CENTER
Published: July 2002

Now I know why so many stories have been written
with the theme: “everything changed in one moment.”
More than 1,000 days have come and gone, and I still remember
one Sunday morning and still follow and feel the effects
of one decision.
Neonatal Viability in the 1990s: Held Hostage by Technology
Authors: MURASKAS JONATHAN , MARSHALL PATRICIA A. , TOMICH PAUL , MYERS THOMAS F. , GIANOPOULOS JOHN G. , THOMASMA DAVID C.
Published: July 2002

The emergence of new obstetrical and neonatal technologies,
as well as more aggressive clinical management, has significantly
improved the survival of extremely low birth weight (ELBW)
infants. This development has heightened concerns about
the limits of viability. ELBW infants, weighing less than
1,000 grams and no larger than the palm of one's hand,
are often described as “miracles” of late twentieth
century technology. Improved survivability of ELBW infants
has provided opportunities for long-term follow-up. Information
on their physical and emotional development contributes
to developing standards of practice regarding their care.
Response to “Germ Line Therapy to Cure Mitochondrial
Disease: Protocol and Ethics of In Vitro Ovum Nuclear Transplantation”
by Donald S. Rubenstein, David C. Thomasma, Eric A. Schon,
and Michael J. Zinaman (CQ Vol 4, No 3)
Authors: Szebik Imre
Published: July 2002

Technical, ethical, and social questions of germ-line
gene interventions have been widely discussed in the literature.
The majority of these discussions focus on planned interventions
executed on the nuclear DNA (nDNA). However, human cells also
contain another set of genes that is the mitochondrial DNA (mtDNA).
As the characteristics of the mtDNA grossly differ from those of
nDNA, so do the social, ethical, psychological, and safety
considerations of possible interventions on this part of the
genetic substance.
The Expected Norm of Random Matrices
Authors: SEGINER YOAV
Published: July 2002

We compare the Euclidean operator norm of a random matrix with the Euclidean norm of
its rows and columns. In the first part of this paper, we show that if A is a random matrix
with i.i.d. zero mean entries, then
E∥A∥h [les ] Kh
(E maxi
∥ai[bull ]
∥h + E maxj
∥aj[bull ]
∥h), where K is
a constant which does not depend on the dimensions or distribution of
A (h, however, does
depend on the dimensions). In the second part we drop the assumption that the entries
of A are i.i.d. We therefore consider the Euclidean operator
norm of a random matrix, A,
obtained from a (non-random) matrix by randomizing the signs of the matrix's entries.
We show that in this case, the best inequality possible (up to a multiplicative constant) is
E∥A∥h [les ] (c log1/4 min
{m, n})h
(E maxi
∥ai[bull ]
∥h + E maxj
∥aj[bull ]
∥h) (m, n the dimensions of the
matrix and c a constant independent of m, n).
Some Spectral Characterizations of Strongly Distance-Regular Graphs
Authors: FIOL M. A.
Published: July 2002

A graph Γ with diameter d is strongly distance-regular if Γ is distance-regular and its
distance-d graph Γd is strongly regular. Some known examples of such graphs are the
connected strongly regular graphs, with distance-d graph Γd = Γ
(the complement of Γ), and the antipodal distance-regular graphs. Here we study some spectral conditions for a
(regular or distance-regular) graph to be strongly distance-regular. In particular, for the
case d = 3 the following characterization is proved. A regular (connected) graph Γ, with
distinct eigenvalues λ0 > λ1 > λ2 > λ3,
is strongly distance-regular if and only if λ2 = −1, and Γ3 is
k-regular with degree k satisfying an expression which depends only on the order
and the different eigenvalues of Γ.
Explicit Limits of Total Variation Distance in Approximations of

Random Logarithmic Assemblies by Related Poisson Processes
Authors: STARK DUDLEY
Published: July 2002

Assemblies are labelled combinatorial objects that can be

decomposed into components. Examples of assemblies include set

partitions, permutations and random mappings. In addition, a

distribution from population genetics called the Ewens sampling

formula may be treated as an assembly. Each assembly has a size

n, and the sum of the sizes of the components sums to

n. When the uniform distribution is put on all assemblies of

size n, the process of component counts is equal in

distribution to a process of independent Poisson variables

Zi conditioned on the event that a

weighted sum of the independent variables is equal to n.

Logarithmic assemblies are assemblies characterized by some

θ > 0 for which

i[ ]Zi → θ.

Permutations and random mappings are logarithmic assemblies; set

partitions are not a logarithmic assembly. Suppose b =

b(n) is a sequence of positive integers for which

b/n → β ε

(0, 1]. For logarithmic assemblies, the total variation

distance db(n) between the laws

of the first b coordinates of the component counting process

and of the first b coordinates of the independent processes

converges to a constant H(β). An explicit

formula for H(β) is given for β

ε (0, 1] in terms of a limit process which depends only
on

the parameter θ. Also, it is shown that

db(n) → 0 if and only if

b/n → 0, generalizing results of Arratia,

Barbour and Tavaré for the Ewens sampling formula. Local limit

theorems for weighted sums of the Zi are

used to prove these results.
Dependent Sets of Constant Weight Binary Vectors
Authors: CALKIN NEIL J.
Published: July 2002

We determine lower bounds for the number of random binary vectors,

chosen uniformly

from vectors of weight k, needed to obtain a dependent set.
On Random Intersection Graphs: The Subgraph Problem
Authors: KAROŃSKI MICHAŁ , SCHEINERMAN EDWARD R. , SINGER-COHEN KAREN B.
Published: July 2002

A new model of random graphs – random intersection graphs
– is introduced. In this model,
vertices are assigned random subsets of a given set. Two vertices are adjacent provided
their assigned sets intersect. We explore the evolution of random intersection graphs by
studying thresholds for the appearance and disappearance of small induced subgraphs. An
application to gate matrix circuit design is presented.
The incidence of slum clearance in England and Wales, 1955–85
Authors: Yelling Jim
Published: July 2002

The article begins by showing the differential impact of slum clearance on regions, conurbations and major cities through the three decades of the slum clearance campaign which began in 1955. It discusses the main methods of clearance procedure, the nature of compensation and the relation of clearance to ‘unfit’ housing. House condition surveys revealed an increasing mismatch between patterns of unfit housing and those of slum clearance and this began, it is argued, in the 1960s. Factors such as the development of property markets, and the rise of owner occupation, had differential economic and political effects which in turn reacted on the incidence of clearance.
‘Till our liberties be secure’: popular sovereignty and public space in Bristol, 1780–1850
Authors: Poole Steve
Published: July 2002

Struggles over the symbolic ownership of Bristol's open spaces were often influenced by association with conflicts between mercantile elites and ‘the people’ over the definition and nature of civic identity. Shifting political and cultural readings of Brandon Hill and Queen Square are here identified and contrasted, offering a fresh interpretation of controversies over ‘improvement’ and gentrification via the fluid appropriation of these sites for the representation of radicalism, citizenship, liberty, respectability or commercialism.
Quantitative relationship betweenMeteosatWV data and positive potential vorticity anomalies: a case study over the Mediterranean
Authors: Georgiev Christo G
Published: July 2002

The correlation between Meteosat water vapour (WV) data and positive anomalies of potential vorticity (PV) is investigated using a case study involving cyclogenesis in the Alpine region and a northwest African depression. Correlation analyses are performed at different isobaric surfaces in the middle and upper troposphere for two latitudinal belts (25–35°– ‘southern’, and 35–52.5°N – ‘northern’). A significant correlation is obtained at 500 hPa (correlation coefficient range: 0.58–0.64). Linear regression models are fitted to the samples from the northern and southern belts. On the basis of these results, the use of WV data as a tool for detection of errors in model‐derived PV fields is discussed. It is concluded that, though some of the discrepancies between PV fields and WV images could be due to errors in the model analysis or prognosis, some mismatches are possibly due to the variable sensitivity of the WV channel because of the changes in pressure over the commonly used PV fields. It is suggested that the comparison of WV data with the field of positive PV anomalies at 500 hPa might be another approach to help solve the problem of verifying and validating numerical output. Copyright © 1999 Royal Meteorological Society
THE THERAPY RELATIONSHIP IN COGNITIVE THERAPY: A REVIEW
Authors: Waddington Louise
Published: July 2002

Cognitive therapy has traditionally assumed that the therapy relationship provides a necessary context for intervention but is insufficient alone to produce therapeutic change. This assumption is reviewed in the light of up-to-date evidence from research studies of cognitive therapy and recommendations are made for further research. Mechanisms by which the therapy relationship may influence outcome and factors influencing the quality of the relationship are briefly discussed and the need for further research highlighted. Implications for the practice of cognitive therapy are suggested.
Rehabilitation of executive functioning: An experimental–clinical
validation of Goal Management Training
Authors: LEVINE BRIAN , ROBERTSON IAN H. , CLARE LINDA , CARTER GINA , HONG JULIA , WILSON BARBARA A. , DUNCAN JOHN , STUSS DONALD T.
Published: July 2002

Two studies assessed the effects of a training
procedure (Goal Management Training, GMT), derived from
Duncan's theory of goal neglect, on disorganized behavior
following TBI. In Study 1, patients with traumatic brain
injury (TBI) were randomly assigned to brief trials of
GMT or motor skills training. GMT, but not motor skills
training, was associated with significant gains on everyday
paper-and-pencil tasks designed to mimic tasks that are
problematic for patients with goal neglect. In Study 2,
GMT was applied in a postencephalitic patient seeking to
improve her meal-preparation abilities. Both naturalistic
observation and self-report measures revealed improved
meal preparation performance following GMT. These studies
provide both experimental and clinical support for the
efficacy of GMT toward the treatment of executive functioning
deficits that compromise independence in patients with
brain damage. (JINS, 2000, 6, 299–312.)
The influence of viewing eye on pseudoneglect magnitude
Authors: McCOURT MARK E. , GARLINGHOUSE MATT , BUTLER JASON
Published: July 2002

Various factors influence the degree of leftward
error (pseudoneglect) that typifies the performance of
normal individuals in line bisection tasks. This experiment
reveals that the eye through which stimuli are viewed also
exerts a modulating influence on spatial attention, as
indexed by significant alterations in the magnitude of
pseudoneglect. Using a forced-choice tachistoscopic line
bisection protocol, 24 participants (12 male; 12 female)
bisected horizontally oriented lines (22.6° w ×
0.39° h) presented to central vision in 3 conditions:
left uniocular viewing (L), right uniocular viewing (R),
and binocular viewing (B). Perceived line midpoint, a measure
of bisection accuracy, deviated significantly leftward
of veridical ( p < .05) in all viewing conditions,
confirming a tonic asymmetry of visuospatial attention
in normal young observers. In addition, a significant influence
of viewing condition was found (p < .05) where
pseudoneglect was greatest in the L condition, followed
by the B and R conditions, respectively. Analysis of the
slopes of the psychometric functions revealed significantly
greater bisection precision in the binocular versus uniocular
viewing conditions (p < .05). The results are
interpreted to suggest that phasic effects on spatial attention
can be produced by uniocular viewing via asymmetric retinotectal
projections. The results are consistent with activation–orientation
theories of attentional asymmetry. (JINS, 2001,
7, 391–395.)
A Broadening of Neuropsychological Practice
Authors: Larøi Frank
Published: July 2002

Far too few books exist on the subject of neuropsychological
rehabilitation beyond the cognitive rehabilitative
approach. However, certain signs seem to suggest that this
situation is about to change, such as the publication of
this book.
Premorbid brain size is a determinant of functional reserve
in abstinent crack-cocaine and crack-cocaine–alcohol-dependent
adults
Authors: SCLAFANI VICTORIA DI , CLARK H. WESTLEY , TOLOU-SHAMS MARINA , BLOOMER COURTNAY W. , SALAS GILBERT A. , NORMAN DAVID , FEIN GEORGE
Published: July 2002

Studies of Alzheimer's disease patients show
that individuals with larger premorbid brains have a later
onset of disease, or a lessened severity of cognitive impairment,
or both. This may be due to a “functional reserve”
associated with the greater number of neurons and synapses
available in larger brains. We used magnetic resonance
imaging and the MicroCog Assessment of Cognitive Functioning
to examine the association between intracranial volume
(premorbid brain size) and neuropsychological function
in abstinent crack-cocaine and crack-cocaine–alcohol
dependent individuals. There were no significant differences
between the crack-only and the crack–alcohol dependent
participants in neuropsychological performance or in intracranial
volume. The abstinent cocaine-dependent individuals (both
crack-only and crack–alcohol) were significantly
impaired in many neuropsychological domains. Intracranial
volume accounted for a significant proportion of the variance
in neuropsychological performance. This result is consistent
with the finding in the Alzheimer's literature that
larger brains can maintain function to a greater degree,
or for a longer period of time, in the face of cerebral
disease or insult. Functional reserve may be a heretofore
little recognized protective mechanism of the brain that
has consequences for the severity of expression of cerebral
disease or insult throughout life. (JINS, 1998,
4, 559–565.)
Timing and force control during a sequential tapping task
in children with and without motor coordination problems
Authors: PIEK JAN P. , SKINNER ROSEMARY A.
Published: July 2002

In the present study a sequential tapping task
was used to compare the planning and execution of finger
tapping sequences in children with motor coordination problems
(clumsy children) and control children. Fifteen children
with significant movement problems were compared to 15
control children matched on age, sex, and Verbal IQ. The
clumsy children took significantly longer to initiate the
movement sequence (i.e., reaction time). During the execution
of the sequence, the clumsy children left their finger
on the tap plate for significantly longer for each tap
than the control children. No significant differences were
found between the groups for the time taken between the
taps, or mean average force. Past research has indicated
that the source of timing problems in clumsy children may
lie in a central timing mechanism possibly the cerebellum,
whereas the evidence from the present study indicates an
impairment of the peripheral processes may be a more important
contributor to timing deficits in clumsy children. (JINS,
1999, 5, 320–329.)
Global–local processing in schizophrenia: Hemispheric
asymmetry and symptom-specific interference
Authors: FERMAN TANIS J. , PRIMEAU MARGARET , DELIS DEAN , JAMPALA CHOWDARY V.
Published: July 2002

The hypothesis of atypical functional hemispheric
asymmetry in schizophrenia is tested using the directed
global–local paradigm, a lateralizing measure of
visual perception. Results indicate low error rates (<
2%) for schizophrenia and normal control groups, but longer
response times for the schizophrenia group. In the normal
group, detection speed of global and local forms did not
differ. In contrast, the schizophrenia group responded
significantly faster to local relative to global forms,
which supports the asymmetry hypotheses of left hemisphere
overactivity–right hemisphere underactivity in schizophrenia.
The normal group exhibited a global interference effect
(slowed response latency to the local target in the presence
of a dissimilar global distractor). When the schizophrenia
group was examined according to symptom type and severity,
high positive symptom severity was associated with local
interference (slowed response latency to the global target
in the presence of dissimilar local distractors). Negative
symptoms were not associated with interference from the
competing local or global forms. Patients with a combination
of high positive and low negative symptoms showed significantly
greater local interference than patients with high negative
and low positive symptoms. Interconnected temporal and
frontal systems are postulated to contribute to this pattern
of perceptual processing efficiency and distractibility
in schizophrenia. (JINS, 1999, 5, 442–451.)
Integrating forest resources into the system of national accounts in Maharashtra, India
Authors: HARIPRIYA G.S.
Published: July 2002

The objective of the study is to construct forest resource accounts for the state of Maharashtra in India and incorporate the value of depletion and degradation of forest resources into the system of national accounts (SNA). The net state domestic product (NSDP) is adjusted for the depletion of the forest resources to obtain Environmentally adjusted net state domestic product (ESDP). The results show that the value added by forests is 3.56 per cent of NSDP and the value of depletion is 19.8 per cent of the estimated value added. The ESDP of Maharashtra is found to be 99.3 per cent of the estimated NSDP. The study has demonstrated that, although the existing database needs further improvement, forest resource accounting is feasible for the state of Maharashtra in India and can serve as an indicator of economy's performance.
Cost-utility analysis of schistosomiasis intervention strategies in Kenya
Authors: KIRIGIA JOSES M.
Published: July 2002

When decisions to intervene in different schistosomiasis severity states are taken in isolation, inefficiencies are unavoidable due to failure to take account of the synergy between community and facility level options. To date no studies have been conducted of the sequential nature of decision-making processes in schistosomiasis. The main aim of this study is to develop a methodology that could be used to compute the costs and health benefits of alternative strategies for ameliorating the burden of illness from schistosomiasis, with a view to determine that strategy which would produce the greatest excess of benefits over cost. In other words, the goal is to develop a conceptual framework that could be used to map out the most efficient path of options for intervention across a spectrum of schistosomiasis states - asymptomatic, mild, moderate, severe, and very severe.

A cost-utility decision analysis (CUDA) model was developed and applied to the population living within the schistosomiasis endemic region of Kenya covered by the Mwea Irrigation Scheme. Both primary and secondary level options were included in the analysis.

The main findings are as follows. Strategies involving treatment at the community level were generally superior to non-treatment community strategies. The selective population praziquantel chemotherapy (SPCPS) was found to be the optimal strategy. Mollusciciding strategies are the most cost-effective among the non-treatment strategies. The results of the sensitivity analyses were, however, mixed. The inconclusive nature of the results indicates that firm policy conclusions cannot be made on the basis of current epidemiological information, and more research is urgently required to establish both the validity and reliability of the health-related quality of life (HRQoL), and the Delphi technique (DT) measurements used in the study.
Why do farmers expand their land into forests? Theories and evidence from Tanzania
Authors: ANGELSEN ARILD , SHITINDI ERIC F. KATEMANSIMBA , AARRESTAD JOSTEIN
Published: July 2002

This paper examines the causes of agricultural land expansion and deforestation in Tanzania. In the theoretical section, two different—and partly contradicting—sets of hypotheses are outlined. These are based on a subsistence approach, emphasising the food or income requirements of farm households, and a market approach, focussing on the relative profitability of agriculture. The statistical analysis shows that increased agricultural output prices, in particular for annual crops, is a major factor behind agricultural expansion. An increase of 1 per cent in output prices leads to about 1 per cent increase in agricultural area. Other factors such as input prices, technology and economic growth are tested and discussed, but the conclusions are less robust. The controversial role of population growth in explaining deforestation is addressed. Generally the results lend support to the market rather than the subsistence approach. JEL classification code: Q12, Q23, C23
Preposition stranding with wh-relatives: a historical survey
Authors: Bergh Gunnar , Seppänen Aimo
Published: July 2002

In the course of their history, English wh-relatives are known to have undergone a syntactic change in their prepositional usage: having originally occurred only with pied-piped prepositions, they came to admit preposition stranding as an alternative pattern. The present article presents an overview of this process, showing a modest beginning of stranding in Late Middle English, an increase in Early Modern English, and then a clear decrease in the written language of today, against a more liberal use in spoken English, standard as well as nonstandard. The drop in the incidence of stranding is thus not an expression of a genuine grammatical change but due to notions of correctness derived from the grammar of Latin and affecting written usage. The general trend of the development outlined is mirrored by relative that, with which the pied piping attested in Middle English completely disappeared from the language.
Jespersen's formalism: problems and extensions
Authors: Di Giorgi Sigfrido
Published: July 2002

This article aims to give a new, rigorous, and exhaustive presentation of Jespersen's formalism published in Analytic Syntax (1937). The formalism is described by means of the Backus metalinguistic formulas (Backus, 1959), which were universally adopted for the description of the syntax of computer programming languages. A modernized version of Jespersen's algorithm is proposed and illustrated with a number of significant examples.
Thing is constructions: the thing is, is what's the right analysis?
Authors: Massam Diane
Published: July 2002

This paper examines an English construction which is very common in speech, but rare in writing. This construction is referred to as the thing is construction, as in: The thing is, is we've got to be strong. First, similarities between this construction and specificational pseudocleft constructions are noted, and it is proposed that the constructions are related. Then, five differences between the two construction types are discussed. An analysis is presented which accounts for the similarities and differences. Central to the analysis is the fact that thing is constructions contain ‘theta-role by recognition’ (Stowell, 1981), or appositive nouns (claim, problem, feeling, etc.), which allows the initial Wh-word to become optional. The paper also considers reduced thing is constructions such as: Our kids are great on vacations, but when they come back, is, they need to play, claiming that these, in a continuum along with clefts and thing is constructions, demonstrate the extreme case of a tendency for be to be used as a focus marker in spoken English.
The use of photographic rates to estimate densities of tigers and other cryptic mammals
Authors: Carbone C. , Christie S. , Conforti K. , Coulson T. , Franklin N. , Ginsberg J. R. , Griffiths M. , Holden J. , Kawanishi K. , Kinnaird M. , Laidlaw R. , Lynam A. , Macdonald D. W. , Martyr D. , McDougal C. , Nath L. , O'Brien T. , Seidensticker J. , Smith D. J. L. , Sunquist M. , Tilson R. , Wan Shahruddin W. N.
Published: July 2002

The monitoring and management of species depends on reliable population estimates, and this can be both difficult and very costly for cryptic large vertebrates that live in forested habitats. Recently developed camera trapping techniques have already been shown to be an effective means of making mark‐recapture estimates of individually identifiable animals (e.g. tigers). Camera traps also provide a new method for surveying animal abundance. Through computer simulations, and an analysis of the rates of camera trap capture from 19 studies of tigers across the species' range, we show that the number of camera days/tiger photograph correlates with independent estimates of tiger density. This statistic does not rely on individual identity and is particularly useful for estimating the population density of species that are not individually identifiable. Finally, we used the comparison between observed trapping rates and the computer simulations to estimate the minimum effort required to determine that tigers, or other species, do not exist in an area, a measure that is critical for conservation planning.
The transcription factor Sox10 is a key regulator of peripheral glial development
Authors: Britsch Stefan , Goerich Derk E. , Riethmacher Dieter , Peirano Reto I. , Rossner Moritz , Nave Klaus-Armin , Birchmeier Carmen , Wegner Michael
Published: July 2002

The molecular mechanisms that determine glial cell fate in the vertebrate nervous system have not been elucidated. Peripheral glial cells differentiate from pluripotent neural crest cells. We show here that the transcription factor Sox10 is a key regulator in differentiation of peripheral glial cells. In mice that carry a spontaneous or a targeted mutation ofSox10, neuronal cells form in dorsal root ganglia, but Schwann cells or satellite cells are not generated. At later developmental stages, this lack of peripheral glial cells results in a severe degeneration of sensory and motor neurons. Moreover, we show that Sox10 controls expression ofErbB3in neural crest cells.ErbB3encodes a Neuregulin receptor, and down-regulation ofErbB3accounts for many changes in development of neural crest cells observed inSox10mutant mice. Sox10 also has functions not mediated by ErbB3, for instance in the melanocyte lineage. Phenotypes observed in heterozygous mice that carry a targetedSox10null allele reproduce those observed in heterozygousSox10Dommice. Haploinsufficiency ofSox10can thus cause pigmentation and megacolon defects, which are also observed inSox10Dom/+ mice and in patients with Waardenburg-Hirschsprung disease caused by heterozygousSOX10mutations.
Closely related proteins MBD2 and MBD3 play distinctive but interacting roles in mouse development
Authors: Hendrich Brian , Guy Jacqueline , Ramsahoye Bernard , Wilson Valerie A. , Bird Adrian
Published: July 2002

MBD2 and MBD3 are closely related proteins with consensus methyl-CpG binding domains. MBD2 is a transcriptional repressor that specifically binds to methylated DNA and is a component of the MeCP1 protein complex. In contrast, MBD3 fails to bind methylated DNA in murine cells, and is a component of the Mi-2/NuRD corepressor complex. We show by gene targeting that the two proteins are not functionally redundant in mice, as Mbd3(−/−) mice die during early embryogenesis, whereas Mbd2(−/−) mice are viable and fertile. Maternal behavior of Mbd2(−/−) mice is however defective and, at the molecular level, Mbd2(−/−) mice lack a component of MeCP1.Mbd2-mutant cells fail to fully silence transcription from exogenous methylated templates, but inappropriate activation of endogenous imprinted genes or retroviral sequences was not detected. Despite their differences, Mbd3 and Mbd2 interact genetically suggesting a functional relationship. Genetic and biochemical data together favor the view that MBD3 is a key component of the Mi-2/NuRD corepressor complex, whereas MBD2 may be one of several factors that can recruit this complex to DNA.
The Arabidopsis HOS1 gene negatively regulates cold signal transduction and encodes a RING finger protein that displays cold-regulated nucleo–cytoplasmic partitioning
Authors: Lee Hojoung , Xiong Liming , Gong Zhizhong , Ishitani Manabu , Stevenson Becky , Zhu Jian-Kang
Published: July 2002

Low temperature is one of the most important environmental stimuli that control gene transcription programs and development in plants. InArabidopsis thaliana, the HOS1 locus is a key negative regulator of low temperature-responsive gene transcription. The recessive hos1 mutation causes enhanced induction of theCBF transcription factors by low temperature as well as of their downstream cold-responsive genes. The hos1 mutant plants flower early, and this correlates with a low level of Flowering Locus C gene expression. The HOS1 gene was isolated through positional cloning. HOS1 encodes a novel protein with a RING finger motif near the amino terminus. HOS1 is ubiquitously expressed in all plant tissues. HOS1–GFP translational fusion studies reveal that HOS1 protein resides in the cytoplasm at normal growth temperatures. However, in response to low temperature treatments, HOS1 accumulates in the nucleus. Ectopic expression of HOS1 in wild-type plants causes cosuppression of HOS1 expression and mimics the hos1 mutant phenotypes.
p53 regulates cell survival by inhibiting PIK3CA in squamous cell carcinomas
Authors: Singh Bhuvanesh , Reddy Pabbathi G. , Goberdhan Andy , Walsh Christine , Dao Su , Ngai Ivan , Chou Ting Chao , O-charoenrat Pornchai , Levine Arnold J. , Rao Pulivarthi H. , Stoffel Archontoula
Published: July 2002

Interactions between the p53 and PI3K/AKTpathways play a significant role in the determination of cell death/survival. In benign cells these pathways are interrelated through the transcriptional regulation of PTEN by p53, which is required for p53-mediated apoptosis. PTEN exerts its effects by decreasing the phosphorylated AKT fraction, thereby diminishing prosurvival activities. However, the link between these pathways in cancer is not known. In this study, PIK3CA, encoding the p110α catalytic subunit of PI3K, is identified as an oncogene involved in upper aerodigestive tract (UADT) carcinomas. Simultaneous abnormalities in both pathways are rare in primary tumors, suggesting that amplification of PIK3CA and mutation ofp53 are mutually exclusive events and either event is able to promote a malignant phenotype. Moreover, the negative effect ofp53 induction on cell survival involves the transcriptional inhibition of PIK3CA that is independent of PTENactivity, as PTEN is not expressed in the primary tumors. Conversely, constitutive activation of PIK3CA results in resistance to p53-related apoptosis in PTEN deficient cells. Thus, p53 regulates cell survival by inhibiting thePI3K/AKT prosurvival signal independent of PTENin epithelial tumors. This inhibition is required for p53-mediated apoptosis in malignant cells.
Requirement of fibroblast growth factor 10 in development of white adipose tissue
Authors: Sakaue Hiroshi , Konishi Morichika , Ogawa Wataru , Asaki Toshiyuki , Mori Toshiyuki , Yamasaki Masahiro , Takata Masafumi , Ueno Hikaru , Kato Shigeaki , Kasuga Masato , Itoh Nobuyuki
Published: July 2002

Fibroblast growth factors (FGFs) are important intercellular signaling molecules in developmental processes. Here, we show that FGF10 is secreted by cultured preadipocytes and that prevention of FGF10 signaling inhibits the expression of C/EBPβ and the subsequent differentiation of these cells. An active form of C/EBPβ rescued differentiation of the cells in which FGF10 signaling was blocked. Development of white adipose tissue and the expression of C/EBPβ in this tissue of FGF10 knockout mice were markedly reduced, and the ability of embryonic fibroblasts derived from FGF10 knockout mice to differentiate into adipocytes was impaired. Therefore, FGF10 plays an important role in adipogenesis, at least partly by contributing to the expression of C/EBPβ through an autocrine/paracrine mechanism.
Thermophilic Bacteria Strictly Obey Szybalski's Transcription Direction Rule and Politely Purine-Load RNAs with Both Adenine and Guanine
Authors: Lao Perry J. , Forsdyke Donald R.
Published: July 2002

When transcription is to the right of the promoter, the “top,” mRNA-synonymous strand of DNA tends to be purine-rich. When transcription is to the left of the promoter, the top, mRNA-template strand tends to be pyrimidine-rich. This transcription-direction rule suggests that there has been an evolutionary selection pressure for the purine-loading of RNAs. The politeness hypothesis states that purine-loading prevents distracting RNA–RNA interactions and excessive formation of double-stranded RNA, which might trigger various intracellular alarms. Because RNA–RNA interactions have a distinct entropy-driven component, the pressure for the evolution of purine-loading might be greater in organisms living at high temperatures. In support of this, we find that Chargaff differences (a measure of purine-loading) are greater in thermophiles than in nonthermophiles and extend to both purine bases. In thermophiles the pressure to purine-load affects codon choice, indicating that some features of their amino acid composition (e.g., high levels of glutamic acid) might reflect purine-loading pressure (i.e., constraints on mRNA) rather than direct constraints on protein structure and function.
Genome Annotation Assessment in Drosophila melanogaster
Authors: Reese Martin G. , Hartzell George , Harris Nomi L. , Ohler Uwe , Abril Josep F. , Lewis Suzanna E.
Published: July 2002

Computational methods for automated genome annotation are critical to our community's ability to make full use of the large volume of genomic sequence being generated and released. To explore the accuracy of these automated feature prediction tools in the genomes of higher organisms, we evaluated their performance on a large, well-characterized sequence contig from the Adh region ofDrosophila melanogaster. This experiment, known as the Genome Annotation Assessment Project (GASP), was launched in May 1999. Twelve groups, applying state-of-the-art tools, contributed predictions for features including gene structure, protein homologies, promoter sites, and repeat elements. We evaluated these predictions using two standards, one based on previously unreleased high-quality full-length cDNA sequences and a second based on the set of annotations generated as part of an in-depth study of the region by a group ofDrosophila experts. Although these standard sets only approximate the unknown distribution of features in this region, we believe that when taken in context the results of an evaluation based on them are meaningful. The results were presented as a tutorial at the conference on Intelligent Systems in Molecular Biology (ISMB-99) in August 1999. Over 95% of the coding nucleotides in the region were correctly identified by the majority of the gene finders, and the correct intron/exon structures were predicted for >40% of the genes. Homology-based annotation techniques recognized and associated functions with almost half of the genes in the region; the remainder were only identified by the ab initio techniques. This experiment also presents the first assessment of promoter prediction techniques for a significant number of genes in a large contiguous region. We discovered that the promoter predictors' high false-positive rates make their predictions difficult to use. Integrating gene finding and cDNA/EST alignments with promoter predictions decreases the number of false-positive classifications but discovers less than one-third of the promoters in the region. We believe that by establishing standards for evaluating genomic annotations and by assessing the performance of existing automated genome annotation tools, this experiment establishes a baseline that contributes to the value of ongoing large-scale annotation projects and should guide further research in genome informatics.
The Complete Mitochondrial DNA Sequence of Scenedesmus obliquus Reflects an Intermediate Stage in the Evolution of the Green Algal Mitochondrial Genome
Authors: Nedelcu Aurora M. , Lee Robert W. , Lemieux Claude , Gray Michael W. , Burger Gertraud
Published: July 2002

Two distinct mitochondrial genome types have been described among the green algal lineages investigated to date: a reduced–derived,Chlamydomonas-like type and an ancestral,Prototheca-like type. To determine if this unexpected dichotomy is real or is due to insufficient or biased sampling and to define trends in the evolution of the green algal mitochondrial genome, we sequenced and analyzed the mitochondrial DNA (mtDNA) ofScenedesmus obliquus. This genome is 42,919 bp in size and encodes 42 conserved genes (i.e., large and small subunit rRNA genes, 27 tRNA and 13 respiratory protein-coding genes), four additional free-standing open reading frames with no known homologs, and an intronic reading frame with endonuclease/maturase similarity. No 5S rRNA or ribosomal protein-coding genes have been identified inScenedesmus mtDNA. The standard protein-coding genes feature a deviant genetic code characterized by the use of UAG (normally a stop codon) to specify leucine, and the unprecedented use of UCA (normally a serine codon) as a signal for termination of translation. The mitochondrial genome of Scenedesmus combines features of both green algal mitochondrial genome types: the presence of a more complex set of protein-coding and tRNA genes is shared with the ancestral type, whereas the lack of 5S rRNA and ribosomal protein-coding genes as well as the presence of fragmented and scrambled rRNA genes are shared with the reduced–derived type of mitochondrial genome organization. Furthermore, the gene content and the fragmentation pattern of the rRNA genes suggest that this genome represents an intermediate stage in the evolutionary process of mitochondrial genome streamlining in green algae.

[The sequence data described in this paper have been submitted to the GenBank data library under accession no. AF204057.]
Human and Mouse Gene Structure: Comparative Analysis and Application to Exon Prediction
Authors: Batzoglou Serafim , Pachter Lior , Mesirov Jill P. , Berger Bonnie , Lander Eric S.
Published: July 2002

We describe a novel analytical approach to gene recognition based on cross-species comparison. We first undertook a comparison of orthologous genomic loci from human and mouse, studying the extent of similarity in the number, size and sequence of exons and introns. We then developed an approach for recognizing genes within such orthologous regions by first aligning the regions using an iterative global alignment system and then identifying genes based on conservation of exonic features at aligned positions in both species. The alignment and gene recognition are performed by new programs calledGLASS and ROSETTA, respectively.ROSETTA performed well at exact identification of coding exons in 117 orthologous pairs tested.