bluuebunny/crossref_metadata_2025 huggingface dataset:
Maximum marking problems
Authors: BIRD RICHARD S.
Published: July 2002

Here are two puzzles for you to solve. First, consider the binary tree in figure 1.
Take a pencil (I am assuming that this is your personal copy of JFP!) and mark
some of the nodes in such a way that the sum of the values of marked nodes is
as large as possible. The catch is that you cannot mark all the nodes: if you mark
a node, then you are not allowed to mark its parent. Equivalently, no two marked
nodes can be contiguous in the tree.

The second puzzle is similar though both the datatype and constraint are different.
Consider the rose tree of figure 2 (a rose tree is a tree with arbitrary branching
structure). Mark some of the nodes so that all marked nodes are now contiguous in
the tree. For example, if you mark the root value 4 and the leaf value 1, then you
must also mark the values 5 and −3 along the path from 4 to 1. Again the idea is
to maximise the sum of the marked nodes. Of course, if all values were nonnegative,
the best solution would be to mark all nodes. But they aren't and the maximum
sum is obtained only by a judicious choice of marking. Answers to both puzzles are
given at the end of the paper.

The Maximum Marking Problem (MMP) is the problem of marking the entries
of some given data structure in such a way that a given constraint is satisfied and
the sum of the values associated with marked entries is as large as possible. By the
end of this pearl, you will be convinced that there is a linear-time solution for both
the puzzles described above.
NATURAL EXPERT: a commercial functional
programming environment
Authors: HUTCHISON NIGEL W. O. , NEUHAUS UTE , SCHMIDT-SCHAUSS MANFRED , HALL CORDY V.
Published: July 2002

NATURAL EXPERT is a product that allows users to
build knowledge-based systems. It uses a
lazy functional language, NATURAL EXPERT LANGUAGE, to
implement backward chaining and
provide a reliable knowledge processing environment in which development can
take place.
Customers from all over the world buy the system and have used it to handle a
variety of
problems, including applications such as airplane servicing and bank loan
assessment. Some
of these are used 10,000 times or more per month.
The dynamic compilation of lazy functional programs
Authors: WAKELING DAVID
Published: July 2002

Lazy functional languages seem to be unsuitable for programming
embedded computers
because their implementations require so much memory for program code and
graph. In
this paper we describe a new abstract machine for the implementation of
lazy functional
languages on embedded computers called the X-machine. The X-machine has
been designed
so that program code can be stored compactly as byte code, yet run quickly
using dynamic
compilation. Our first results are promising – programs typically
require only 33% of the
code space of an ordinary implementation, but run at 75% of the speed.
Future work needs
to concentrate on reducing the size of statically-allocated data and the
run-time system, and
on developing a more detailed understanding of throw-away compilation.
Functorial ML
Authors: JAY C. B. , BELLÈ G. , MOGGI E.
Published: July 2002

We present an extension of the Hindley–Milner type system that supports a generous class
of type constructors called functors, and provide a parametrically polymorphic algorithm for
their mapping, i.e. for applying a function to each datum appearing in a value of constructed
type. The algorithm comes from shape theory, which provides a uniform method for locating
data within a shape. The resulting system is Church–Rosser and strongly normalizing, and
supports type inference. Several different semantics are possible, which affects the choice of
constants in the language, and are used to illustrate the relationship to polytypic programming.
A theory of weak bisimulation for Core CML
Authors: FERREIRA WILLIAM , HENNESSY MATTHEW , JEFFREY ALAN
Published: July 2002

Concurrent ML (CML) is an extension of Standard ML of New Jersey
with concurrent
features similar to those of process algebra. In this paper, we build upon
John Reppy's
reduction semantics for CML by constructing a compositional operational
semantics for a
fragment of CML, based on higher-order process algebra. Using the operational
semantics we
generalise the notion of weak bisimulation equivalence to build a semantic
theory of CML.
We give some small examples of proofs about CML expressions, and show that
our semantics
corresponds to Reppy's up to weak first-order bisimulation.
Applications of Plotkin-terms:
partitions and morphisms for closed terms
Authors: STATMAN RICHARD , BARENDREGT HENK
Published: July 2002

This theoretical pearl is about the closed term model of pure untyped lambda-terms modulo
β-convertibility. A consequence of one of the results is that for arbitrary distinct combinators
(closed lambda terms) M, M′, N, N′ there is a combinator H such that

formula here

The general result, which comes from Statman (1998), is that uniformly r.e. partitions of the
combinators, such that each ‘block’ is closed under β-conversion, are of the form
{H−1{M}}M∈ΛΦ.
This is proved by making use of the idea behind the so-called Plotkin-terms, originally devised
to exhibit some global but non-uniform applicative behaviour. For expository reasons we
present the proof below. The following consequences are derived: a characterization of
morphisms and a counter-example to the perpendicular lines lemma for β-conversion.
Towards a computer-based learning environment: a pilot study in the use
of FirstClass
Authors: GILLESPIE JOHN
Published: July 2002

This article outlines the nature of the FirstClass computer conferencing program and
considers its effectiveness in helping to develop a computer-based learning environment in
modern languages at the University of Ulster. A wide range of different transactions is outlined
and surveys of staff and student reactions are assessed. Their positive responses demonstrate that
FirstClass is effective in establishing such an environment, enable us to draw encouraging lessons
from our experience and indicate exciting possibilities of immediate further development.
EUROCALL Annual Report 1999/2000
Authors: THOMPSON JUNE
Published: July 2002

EUROCALL continued to operate from the Language Institute at the
University of Hull. The former CTI Centre for Modern Languages became part of a
much larger Subject Centre for Languages, Linguistics and Area Studies, in turn part
of the Learning and Teaching Support Network (LTSN) funded by the UK Higher
Education funding bodies. The team at Hull is responsible for aspects of the
Centre’s activities relating to communication and information technologies
(C&IT), and consists of June Thompson, Fred Riley and Julie Venner who serves as
EUROCALL membership secretary. We were pleased to be joined in May 2000 by Janet
Bartle who is the Academic Co-ordinator, C&IT for the Subject Centre.
Ethical and legal issues in the care of demented people
Authors: Jones RG
Published: July 2002

This paper addresses the ethical and legal issues which arise in the UK in the care of demented people, updating and revising the 1993 review in this journal. In 1993 the ‘end of medical ethics’ had recently been suggested, an American fear that the doctor‘s responsibility and authority would be fatally eroded by administrators and cost controllers, concerned only with budgets. These concerns persist.
Measuring outcomes of long-term care for older people
Authors: Cotter AJE , Salvage AV , Meyer JE , Bridges J
Published: July 2002

There comes a time in the lives of a minority of older people when the extent of their disabilities makes it impossible for them to continue living in their own homes. When this happens, long-term institutional care may be the only option. Given that most residents in long-term care are over 75 years old and that the numbers in this age group will increase into the next century, we can expect an increase in the number of people requiring long-term care.
A filter model for mobile processes
Authors: DAMIANI FERRUCCIO , DEZANI-CIANCAGLINI MARIANGIOLA , GIANNINI PAOLA
Published: July 2002

This paper presents a filter model for π-calculus and shows
its full abstraction with respect
to a ‘may’ operational semantics. The model is introduced in
the form of a type assignment
system. Types are related by a preorder that mimics the operational behaviour
of terms. A
subject expansion theorem holds. Terms are interpreted as filters of types:
this interpretation
is compositional. The proof of full abstraction relies on a notion of realizability
of types and
on the construction of terms, which test when an arbitrary term has a fixed
type.
The call-by-value λ-calculus: a semantic investigation
Authors: PRAVATO ALBERTO , della ROCCA SIMONA RONCHI , ROVERSI LUCA
Published: July 2002

This paper is about a categorical approach for modelling the pure (i.e., without constants)
call-by-value λ-calculus, defined by Plotkin as a restriction of the call-by-name λ-calculus. In
particular, we give the properties that a category Cbv must enjoy to describe a model of
call-by-value λ-calculus. The category Cbv is general enough to catch models in Scott
Domains and Coherence Spaces.
1957: A Divided Europe. European Cinema at the Time of the Rome Treaty
Authors: Sorlin Pierre
Published: July 2002

The 1950s were the heyday of cinema in Europe. Rather than competing with Hollywood studios, European film companies preferred to stick to old, well established recipes. Germany recycled one of its cultural traditions, Heimat. Despite the poverty of their plots and the weakness of their protagonists, the Heimatfilme succeeded by celebrating an unspoilt, soothing wilderness. The Italian counterpart of Heimatfilme was melodrama. If family dramas remained much appreciated in the Peninsula, the filmmakers were clever enough to shift their characters from an ill-defined epoch to the contemporary world. So, while urban Germany was pining for its wild, empty mountains, rural Italy was contemplating its domestic comforts to come. With the Carry On series, Britain was loyal to comedies, which filled the main part of the programmes. The plots – which merely dealt with private affairs – were humorous, harmless, always deprived of authentic social background. The European cinemas of the 1950s were directed towards large, mostly ‘popular’ audiences of people who used to leave their houses and gather in town centres on Saturday evenings. These cinemas did not produce any masterpieces but they were the most characteristic, and the most appreciated, form of entertainment in the middle of the century. It was not art, but it was ‘popular’ culture.
The Instability of the Standard Justification for
Physician-Assisted Suicide
Authors: CAVANAUGH THOMAS A.
Published: July 2002

Proponents commonly justify the legalization of physician-assisted
suicide (PAS) in terms of a patient's wanting to die (autonomy)
and the patient's having a medically established good reason for
suicide. These are the common elements of the standard justification
offered for the legalization of PAS. In what follows, I argue that these
two conditions exist in significant tension with one another, operating
according to distinct dynamics that render the justification for PAS an
unstable “let it be so” basis for public policy. Moreover,
no natural connection keeps these two criteria united. Indeed—as
I argue—the two elements of the justification oppose and threaten
to exclude one another. Thus, the PAS justification is too labile a basis
for sound public policy.
Gene Patents Can Be Ethical
Authors: McGEE GLENN
Published: July 2002

When one examines the emerging debate about genetic
patenting, it becomes clear that those who oppose so-called
“gene patents” misunderstand genetics or apply
inappropriate moral and jurisprudential theory. In this
brief essay I examine some arguments against gene patents
of the “methods for detection” variety, and
conclude that patents on methods for detecting the presence
of a genetic correlation with disease-related (and other)
phenotypes can be appropriate, and that with several precautions
the U.S. Patent and Trademark Office should continue granting
patent protection to investigators who generate genetic
disease diagnostic innovations.
Commentary
Authors: Gatter Robert
Published: July 2002

This case is not about whether retransplant
candidates should receive organs over first-time candidates,
or whether risks of transplant failure from psychological
or social factors are relevant to allocating organs. Rather,
it concerns only this patient's qualifications to
wait for a kidney transplant. Should the patient's
prior transplants, noncompliance, and poor social network
exclude her even from the waiting list? Do attending physicians
inappropriately favor their patients over all others in
need of transplants just by listing them? The answers turn
on the difference between identifying a transplant need
and allocating an organ.
The Horns of the Dilemma Are Sharp
Authors: HOLZMAN IAN R.
Published: July 2002

I would like to present the details of an actual
case from my own experience over which I, along with the
family, have agonized. I think this case brings into focus
some of the unique issues in perinatal medicine where multiple
patients, some real and some potential, can enter into
a single decision. I hope that through this presentation
others may gain insight into the complexities of applied
ethics in perinatal medicine.
HLA class I molecules in implantation
Authors: Loke YW , King Ashley
Published: July 2002

Because half its genes are inherited from the father, the embryo during pregnancy has been frequently compared to an allograft transplanted into the maternal uterus. The question why the embryo is, therefore, not rejected by the mother's immune response in the same way as other allografts has still not been satisfactorily answered. Recent investigations indicate that this analogy may not be as close as it initially appears. One major difference is the expression of an unusual combination of HLA class I molecules by the placental trophoblast cells which invade into uterine decidua during implantation. Furthermore, the lymphoid population in the uterus potentially capable of interacting with these trophoblast HLA class I antigens also appears to be unique. These observations have led to the suggestion that implantation might utilise a novel immune system which is different to that seen in clinical transplantation immunology. Much research effort is now directed towards the elucidation of the mechanisms involved and the outcome of this interaction because this is likely to be how implantation is controlled.
Camelot – a database for climate model output
Authors: Gregory J M , Tett S F B , Hibling E L
Published: July 2002

Camelot is a database system designed for output from the climate model run by the Hadley Centre of the UK Meteorological Office. It contains metadata for climate model output held in a tape archive and on the workstation system used for analysis. The system is required because of the large and rapidly growing volume of archive data and the great variety of uses of the climate model. Camelot enables the user to find out about what has been archived and to retrieve data selectively to the workstations with specifications given in terms of metadata rather than files, without recopying data already held online. The PV‐WAVE analysis environment used on the workstation system also allows the user to access the data by reference to its metadata. Copyright © 2000 Royal Meteorological Society
Mesoscale analysis of a comma cloud observed during FASTEX
Authors: Williams K D
Published: July 2002

A cold‐air comma cloud crossed southern Britain early on 18 February 1997 bringing strong gusts and convective precipitation. Development of the comma cloud occurred in association with a positive upper tropospheric potential vorticity (PV) anomaly. A mesoscale analysis of the comma cloud was carried out using special three‐hourly soundings from UK radiosonde stations together with data from rainfall radar, satellite, NWP model output and a wind‐profiling radar. The analysis reveals that the comma cloud tail was of ana‐form whilst the polar cold front (behind which the comma cloud developed) was kata‐form. Further analysis indicates that the polar cold θw front and the comma cloud front were tending to become one entity at the surface and can thus be considered an example of a kata‐cold front undergoing a partial transition to more of an ana‐form locally in the region of an upper tropospheric positive PV anomaly. Copyright © 2000 Royal Meteorological Society
Characteristics of recent UK flood‐producing rainfalls in relation to the Flood Studies Report design event method
Authors: Faulkner D S
Published: July 2002

Weather radar images were used in an investigation of the rainfall events which gave rise to various damaging UK floods in the 1990s. Radar data of sufficient quality were available for seven events from an initial list of 26. The relative temporal and spatial rainfall profiles of each event are displayed and summarised, along with the antecedent catchment wetnesses. Catchment rainfall totals were obtained from daily raingauges. These characteristics are compared with their equivalents in a standard method of flood estimation, the design event method of the Flood Studies Report. The results highlight the complexity of rainfall fields. The wide variety of event characteristics includes some large deviations from their counterparts in the design event. Six of the catchments were modelled with the design event method in order to assess the significance of the deviations in terms of the estimated flood peaks. The rainfall depth and duration and the antecedent catchment wetness were found to have a significant influence within the design event method. The temporal profile was of lesser importance, for most of the events studied. Copyright © 1997 Royal Meteorological Society
The mushroom configuration in water vapour imagery and operational applications
Authors: Martín F , Elizaga F , Riosalido R
Published: July 2002

This paper deals with ‘mushroom‐shaped’ patterns that may be observed in water vapour (WV) imagery. Its associated conceptual model has been adapted from the ‘T’ configuration. For this model some remarkable properties of WV imagery have been used: the spatial and temporal continuity of atmospheric structures, the more detailed upper‐level circulation features and the possibility of observing and monitoring relationships between them. Using this model, and from the kinematic viewpoint, it is possible to infer some features such as deformation zones, rotation centres (vorticity centres) and relative maxima of wind in the upper‐middle‐level flows. Some examples are presented to show the usefulness of this conceptual model for the interpretation of WV imagery, the diagnosis of upper‐middle‐level flow and the evaluation of the numerical model. Copyright © 1999 Royal Meteorological Society
The global relocatable regional weather prediction model of the German Military Geophysical Office
Authors: Prenosil Thomas , Amtmann Richard , Derichs Heinz
Published: July 2002

A regional numerical weather prediction system, consisting of an analysis scheme, a forecast model and a variety of interpretation, visualization and military application tools, named ‘BLM’ has been routinely operating at the German Military Geophysical Office (GMGO) since 1984. At that time, the grid domain was confined to Central Europe and parts of the North Atlantic, where a polar stereographic map projection was appropriate. Owing to increasing user demands, the system had to be made relocatable to provide numerical forecasts at any location of the globe. The relocatable version, called ‘RBL’, is still formulated on a stereographic plane, which is now defined using a rotated geographical system with an artificial north pole right in the middle of the domain. This approach is well known. However, most of the current numerical weather prediction systems are defined on a horizontal latitude–longitude grid, so that the equator in rotated coordinates runs through the centre of the forecast area. The main advantages of the horizontal coordinate transformation used by the ‘RBL’ are numerical stability for a large and economical time step, which enables the model to be run on a computer with limited power, and an invariant map factor all over the globe, which eases the interpretation of the model results for different locations. Copyright © 1999 Royal Meteorological Society
THE SPECIFICITY OF COGNITIVE PERSONALITY DIMENSIONS IN CLUSTER C PERSONALITY DISORDERS
Authors: Nordahl Hans M. , Stiles Tore C.
Published: July 2002

The aim of the study was to examine whether there are specific cognitive personality traits that are related to specific cluster C personality disorders as suggested by Beck's cognitive model. The study included 135 psychiatric outpatients and 41 healthy controls. The subjects were diagnosed according to DSM-III-R axis I and axis II. The cognitive dimensions of sociotropy, autonomy and dysfunctional attitudes were assessed. The results indicated some cognitive specificity, especially when the effects of a lifetime depressive disorder were statistically controlled for. Dependent personality disorder was significantly associated with higher scores on all sociotropic subscales and dysfunctional attitudes. Avoidant personality disorder was significantly associated with the sociotropic subscales “concern about disapproval” and “pleasing others” as well as dysfunctional attitudes, while obsessive-compulsive personality disorder was associated with only higher scores on the sociotropic subscale “concern about disapproval”.
Verbal and design fluency in patients with frontal lobe lesions
Authors: BALDO JULIANA V. , SHIMAMURA ARTHUR P. , DELIS DEAN C. , KRAMER JOEL , KAPLAN EDITH
Published: July 2002

The ability to generate items belonging to categories in verbal
fluency tasks has been attributed to frontal cortex. Nonverbal
fluency (e.g., design fluency) has been assessed separately
and found to rely on the right hemisphere or right frontal cortex.
The current study assessed both verbal and nonverbal fluency
in a single group of patients with focal, frontal lobe lesions
and age- and education-matched control participants. In the
verbal fluency task, participants generated items belonging
to both letter cues (F, A, and S)
and category cues (animals and boys' names). In the design
fluency task, participants generated novel designs by connecting
dot arrays with 4 straight lines. A switching condition was
included in both verbal and design fluency tasks and required
participants to switch back and forth between different sets
(e.g., between naming fruits and furniture). As a group, patients
with frontal lobe lesions were impaired, compared to control
participants, on both verbal and design fluency tasks. Patients
with left frontal lesions performed worse than patients with
right frontal lesions on the verbal fluency task, but the 2
groups performed comparably on the design fluency task. Both
patients and control participants were impacted similarly by
the switching conditions. These results suggest that verbal
fluency is more dependent on left frontal cortex, while nonverbal
fluency tasks, such as design fluency, recruit both right and
left frontal processes. (JINS, 2001, 7,
586–596.)
Treatment of a case of phonological alexia with agraphia
using the Auditory Discrimination in Depth (ADD) Program
Authors: CONWAY TIM W. , HEILMAN PATRICIA , ROTHI LESLIE J.G. , ALEXANDER ANN W. , ADAIR JOHN , CROSSON BRUCE A. , HEILMAN KENNETH M.
Published: July 2002

Phonological alexia and agraphia are acquired disorders
characterized by an impaired ability to convert graphemes
to phonemes (alexia) or phonemes to graphemes (agraphia).
These disorders result in phonological errors typified
by adding, omitting, shifting, or repeating phonemes in
words during reading or graphemes when spelling. In developmental
dyslexia, similar phonological errors are believed to result
from deficient phonological awareness, an oral language
skill that manifests itself in the ability to notice, think
about, or manipulate the individual sounds in words. The
Auditory Discrimination in Depth (ADD) program has been
reported to train phonological awareness in developmental
dyslexia and dysgraphia. We used a multiple-probe design
to evaluate the ADD program's effectiveness with a
patient with a mild phonological alexia and mixed agraphia
following a left hemisphere infarction. Large gains in
phonological awareness, reading and spelling nonwords,
and reading and spelling real words were demonstrated.
A follow-up reassessment, 2 months posttreatment, found
the patient had maintained treatment gains in phonological
awareness and reading, and attained additional improvement
in real word reading. (JINS, 1998, 4,
608–620.)
The relationship between employment and neuropsychological
impairment in HIV infection
Authors: VAN GORP WILFRED G. , BAERWALD JEFFREY P. , FERRANDO STEPHEN J. , McELHINEY MARTIN C. , RABKIN JUDITH G.
Published: July 2002

The relationship between neurocognitive impairment
and employment in a cohort of 130 predominantly symptomatic
individuals with HIV–1 infection was examined. Participants
were classified as employed (full or part-time for pay)
or unemployed (N = 64) and administered a neuropsychological
test battery. When covarying for CD4 count, age, and physical
limitations, the results revealed that unemployed men performed
below that of employed participants on tasks of memory,
set shifting–cognitive flexibility, and psychomotor
speed. The results are discussed within the context of
similar findings in other illnesses. (JINS, 1999,
5, 534–539.)
Tanzania's soil wealth
Authors: BREKKE KJELL ARNE , IVERSEN VEGARD , AUNE JENS B.
Published: July 2002

This paper adopts soil scientific models of soil productivity and degradation in Tanzania into an intertemporal optimisation framework. The farmers choose labour input, capital investment and fertiliser input to maximise soil wealth, i.e., the present value of soil rent. First we focus exclusively on soil mining, considering the nutrient stocks as determinants of land productivity. Next, we focus on soil erosion, and include rooting depth as determinant of land productivity. We compute the soil wealth under the assumption that the opportunity cost of labour is equal to current wages, or alternatively equal to zero. Our estimates suggest that the potential gains from change in agricultural management are considerable. Moreover, the shadow price on root depth and hence the returns to land conservation investments are highly sensitive to our labour market assumptions. We also find that the value of the eroded soil amounts to 12–17 per cent of the value of Hicksian income, and the savings required to maintain consumption amounts to 13–29 per cent of the contribution to GDP.
Induced New Mutation of D1 Serine-268 in Soybean Photosynthetic Cell Cultures Produced Atrazine Resistance, Increased Stability of S2QB - and S3QB - States, and Increased Sensitivity to Light Stress
Authors: Alfonso M. , Pueyo J. J. , Gaddour K. , Etienne A. L. , Kirilovsky D. , Picorel R.
Published: July 2002

We have isolated several herbicide-resistant cell lines from photosynthetic cell suspensions of soybean (Glycine max) that possessed different levels of herbicide resistance, photosystem II activity, and chlorophyll a/b ratio. We have further studied the STR7 mutant, which showed the highest level of resistance to atrazine as well as a cross-resistance to 3-(3,4-dichlorophenyl)-1,1-dimethylurea (50- and 3-fold, respectively, compared with the wild type). Sequencing of the psbA gene (coding for the D1 polypeptide of photosystem II) from this mutant revealed a single change, serine-268 to proline, in the D1 protein. To our knowledge, this substitution has not previously been described in any photosynthetic organism. In addition to affecting atrazine resistance, this single amino acid change caused a decrease in the electron transfer rate between the secondary acceptors QA and QB and a stabilization of the S2QB- and S3QB- states. The mutant also showed a larger antenna size, an increase in non-QB-reducing centers, and a higher sensitivity to light stress. The unusual stability of the S2QB- and S3QB- states indicates that STR7 belongs to a new class of QB-site mutants.
NO3- and ClO3- Fluxes in the chl1-5 Mutant of Arabidopsis thaliana (Does the CHL1-5 Gene Encode a Low-Affinity NO3- Transporter?)
Authors: Touraine B. , Glass ADM.
Published: July 2002

The CHL1 gene is considered to encode a low-affinity transport system (LATS) for NO3- in Arabidopsis thaliana (Y.-F. Tsay, J.I. Schroeder, K.A. Feldmann, N.M. Crawford [1993] Cell 72: 705–713). However, the anticipated reduced NO3- uptake by the LATS associated with loss of CHL1 gene activity in chl1-5 deletion mutants was evident only when plants were grown on NH4NO3. When KNO3 was the sole N source, NO3- accumulation and short-term tracer influx (using 13NO3- and 15NO3-) in leaves and roots of wild-type and mutant plants were essentially identical. Nevertheless, root uptake of 36ClO3- by the LATS and ClO3- accumulation in roots and shoots of mutant plants were significantly lower than in wild-type plants when grown on KNO3. One explanation for these results is that a second LATS is able to compensate for the chl1-5 deficiency in KNO3-grown plants. Growth on NH4NO3 may down-regulate the second LATS enough that the anticipated difference in NO3- uptake becomes apparent.
Higher Activity of an Aldehyde Oxidase in the Auxin-Overproducing superroot1 Mutant ofArabidopsis thaliana1
Authors: Seo Mitsunori , Akaba Shuichi , Oritani Takayuki , Delarue Marianne , Bellini Catherine , Caboche Michel , Koshiba Tomokazu
Published: July 2002

Aldehyde oxidase (AO; EC 1.2.3.1) activity was measured in seedlings of wild type or an auxin-overproducing mutant, superroot1(sur1), of Arabidopsis thaliana. Activity staining for AO after native polyacrylamide gel electrophoresis separation of seedling extracts revealed that there were three major bands with AO activity (AO1–3) in wild-type and mutant seedlings. One of them (AO1) had a higher substrate preference for indole-3-aldehyde. This AO activity was significantly higher in sur1 mutant seedlings than in the wild type. The difference in activity was most apparent 7 d after germination, the same time required for the appearance of the remarkable sur1 phenotype, which includes epinastic cotyledons, elongated hypocotyls, and enhanced root development. Higher activity was observed in the root and hypocotyl region of the mutant seedlings. We also assayed the indole-3-acetaldehyde oxidase activity in extracts by high-performance liquid chromatography detection of indole-3-acetic acid (IAA). The activity was about 5 times higher in the extract of thesur1 seedlings, indicating that AO1 also has a substrate preference for abscisic aldehyde. Treatment of the wild-type seedlings with picloram or IAA caused no significant increase in AO1 activity. This result suggested that the higher activity of AO1 insur1 mutant seedlings was not induced by IAA accumulation and, thus, strongly supports the possible role of AO1 in IAA biosynthesis in Arabidopsis seedlings.
Expression Pattern of the Carrot EP3Endochitinase Genes in Suspension Cultures and in Developing Seeds1
Authors: van Hengel Arjon J. , Guzzo Flavia , van Kammen Ab , de Vries Sacco C.
Published: July 2002

Carrot (Daucus carota) extracellular protein 3 (EP3) class IV endochitinases were previously identified based on their ability to rescue somatic embryos of the temperature-sensitive cell line ts11. Whole-mount in situ hybridization revealed that a subset of the morphologically distinguishable cell types in embryogenic and nonembryogenic suspension cultures, including ts11, express EP3 genes. No expression was found in somatic embryos. In carrot plants EP3 genes are expressed in the inner integumentary cells of young fruits and in a specific subset of cells located in the middle of the endosperm of mature seeds. No expression was found in zygotic embryos. These results support the hypothesis that the EP3 endochitinase has a “nursing” function during zygotic embryogenesis and that this function can be mimicked by suspension cells during somatic embryogenesis.
Characterization ofLeMir, a Root-Knot Nematode-Induced Gene in Tomato with an Encoded Product Secreted from the Root1
Authors: Brenner Eric D. , Lambert Kris N. , Kaloshian Isgouhi , Williamson Valerie M.
Published: July 2002

A tomato gene that is induced early after infection of tomato (Lycopersicon esculentum Mill.) with root-knot nematodes (Meloidogyne javanica) encodes a protein with 54% amino acid identity to miraculin, a flavorless protein that causes sour substances to be perceived as sweet. This gene was therefore namedLeMir (L.esculentummiraculin). Sequence similarity places the encoded protein in the soybean trypsin-inhibitor family (Kunitz). LeMir mRNA is found in root, hypocotyl, and flower tissues, with the highest expression in the root. Rapid induction of expression upon nematode infection is localized to root tips. In situ hybridization shows that LeMir is expressed constitutively in the root-cap and root-tip epidermis. TheLeMir protein product (LeMir) was produced in the yeastPichia pastoris for generation of antibodies. Western-blot analysis showed that LeMir expression is up-regulated by nematode infection and by wounding. LeMir is also expressed in tomato callus tissue. Immunoprint analysis revealed that LeMir is expressed throughout the seedling root, but that levels are highest at the root/shoot junction. Analysis of seedling root exudates revealed that LeMir is secreted from the root into the surrounding environment, suggesting that it may interact with soil-borne microorganisms.
Identification of a Ca2+/H+ Antiport in the Plant Chloroplast Thylakoid Membrane1
Authors: Ettinger William F. , Clear Anne M. , Fanning Katheryn J. , Peck Mary Lou
Published: July 2002

To assess the availability of Ca2+ in the lumen of the thylakoid membrane that is required to support the assembly of the oxygen-evolving complex of photosystem II, we have investigated the mechanism of45Ca2+ transport into the lumen of pea (Pisum sativum) thylakoid membranes using silicone-oil centrifugation. Trans-thylakoid Ca2+ transport is dependent on light or, in the dark, on exogenously added ATP. Both light and ATP hydrolysis are coupled to Ca2+ transport through the formation of a transthylakoid pH gradient. The H+-transporting ionophores nigericin/K+ and carbonyl cyanide 3-chlorophenylhydrazone inhibit the transport of Ca2+. Thylakoid membranes are capable of accumulating up to 30 nmol Ca2+ mg−1 chlorophyll from external concentrations of 15 μm over the course of a 15-min reaction. These results are consistent with the presence of an active Ca2+/H+ antiport in the thylakoid membrane. Ca2+ transport across the thylakoid membrane has significant implications for chloroplast and plant Ca2+homeostasis. We propose a model of chloroplast Ca2+regulation whereby the activity of the Ca2+/H+antiporter facilitates the light-dependent uptake of Ca2+by chloroplasts and reduces stromal Ca2+ levels.
Isolation and Characterization of cDNAs Expressed in the Early Stages of Flavonol-Induced Pollen Germination in Petunia
Authors: Guyon Virginie N. , Astwood James D. , Garner Ethan C. , Dunker A. Keith , Taylor Loverine P.
Published: July 2002

Petunia (Petunia hybrida) pollen requires flavonols (Fl) to germinate. Adding kaempferol to Fl-deficient pollen causes rapid and synchronous germination and tube outgrowth. We exploited this system to identify genes responsive to Fls and to examine the changes in gene expression that occur during the first 0.5 h of pollen germination. We used a subtracted library and differential screening to identify 22 petunia germinating pollen clones. All but two were expressed exclusively in pollen and half of the clones were rare or low abundance cDNAs. RNA gel-blot analysis showed that the steady-state transcript levels of all the clones were increased in response to kaempferol. The sequences showing the greatest response to kaempferol encode proteins that have regulatory or signaling functions and include S/D4, a leucine-rich repeat protein, S/D1, a LIM-domain protein, and D14, a putative Zn finger protein with a heme-binding site. Eight of the clones were novel including S/D10, a cDNA only expressed very late in pollen development and highly up-regulated during the first 0.5 h of germination. The translation product of the S/D3 cDNA shares some features with a neuropeptide that regulates guidance and growth in the tips of extending axons. This study confirmed that the bulk of pollen mRNA accumulates well before germination, but that specific sequences are transcribed during the earliest moments of Fl-induced pollen germination.
Stearoyl-Acyl Carrier Protein and Unusual Acyl-Acyl Carrier Protein Desaturase Activities Are Differentially Influenced by Ferredoxin
Authors: Schultz David J. , Suh Mi Chung , Ohlrogge John B.
Published: July 2002

Acyl-acyl carrier protein (ACP) desaturases function to position a single double bond into an acyl-ACP substrate and are best represented by the ubiquitous Δ9 18:0-ACP desaturase. Several variant acyl-ACP desaturases have also been identified from species that produce unusual monoenoic fatty acids. All known acyl-ACP desaturase enzymes use ferredoxin as the electron-donating cofactor, and in almost all previous studies the photosynthetic form of ferredoxin rather than the non-photosynthetic form has been used to assess activity. We have examined the influence of different forms of ferredoxin on acyl-ACP desaturases. Using combinations of in vitro acyl-ACP desaturase assays and [14C]malonyl-coenzyme A labeling studies, we have determined that heterotrophic ferredoxin isoforms support up to 20-fold higher unusual acyl-ACP desaturase activity in coriander (Coriandrum sativum), Thunbergia alata, and garden geranium (Pelargonium ×hortorum) when compared with photosynthetic ferredoxin isoforms. Heterotrophic ferredoxin also increases activity of the ubiquitous Δ9 18:0-ACP desaturase 1.5- to 3.0-fold in both seed and leaf extracts. These results suggest that ferredoxin isoforms may specifically interact with acyl-ACP desaturases to achieve optimal enzyme activity and that heterotrophic isoforms of ferredoxin may be the in vivo electron donor for this reaction.
Molecular and Biochemical Characterization of Postharvest Senescence in Broccoli
Authors: Page Tania , Griffiths Gareth , Buchanan-Wollaston Vicky
Published: July 2002

Postharvest senescence in broccoli (Brassica oleracea L. var Italica) florets results in phenotypic changes similar to those seen in developmental leaf senescence. To compare these two processes in more detail, we investigated molecular and biochemical changes in broccoli florets stored at two different temperatures after harvest. We found that storage at cooler temperatures delayed the symptoms of senescence at both the biochemical and gene expression levels. Changes in key biochemical components (lipids, protein, and chlorophyll) and in gene expression patterns occurred in the harvested tissue well before any visible signs of senescence were detected. Using previously identified senescence-enhanced genes and also newly isolated, differentially expressed genes, we found that the majority of these showed a similar enhancement of expression in postharvest broccoli as in developmental leaf senescence. At the biochemical level, a rapid loss of membrane fatty acids was detected after harvest, when stored at room temperature. However, there was no corresponding increase in levels of lipid peroxidation products. This, together with an increased expression of protective antioxidant genes, indicated that, in the initial stages of postharvest senescence, an orderly dismantling of the cellular constituents occurs, using the available lipid as an energy source. Postharvest changes in broccoli florets, therefore, show many similarities to the processes of developmental leaf senescence.
Abscisic Acid-Induced Actin Reorganization in Guard Cells of Dayflower Is Mediated by Cytosolic Calcium Levels and by Protein Kinase and Protein Phosphatase Activities
Authors: Hwang Jae-Ung , Lee Youngsook
Published: July 2002

In guard cells of open stomata under daylight, long actin filaments are arranged at the cortex, radiating out from the stomatal pore. Abscisic acid (ABA), a signal for stomatal closure, induces rapid depolymerization of cortical actin filaments and the slower formation of a new type of actin that is randomly oriented throughout the cell. This change in actin organization has been suggested to be important in signaling pathways involved in stomatal closing movement, since actin antagonists interfere with normal stomatal closing responses to ABA. Here we present evidence that the actin changes induced by ABA in guard cells of dayflower (Commelina communis) are mediated by cytosolic calcium levels and by protein phosphatase and protein kinase activities. Treatment of guard cells with CaCl2 induced changes in actin organization similar to those induced by ABA. Removal of extracellular calcium with EGTA inhibited ABA-induced actin changes. These results suggest that Ca2+ acts as a signal mediator in actin reorganization during guard cell response to ABA. A protein kinase inhibitor, staurosporine, inhibited actin reorganization in guard cells treated with ABA or CaCl2, and also increased the population of cells with long radial cortical actin filaments in untreated control cells. A protein phosphatase inhibitor, calyculin A, induced fragmentation of actin filaments in ABA- or CaCl2-treated cells and in control cells, and inhibited the formation of randomly oriented long actin filaments induced by ABA or CaCl2. These results suggest that protein kinase(s) and phosphatase(s) participate in actin remodeling in guard cells during ABA-induced stomatal closure.
Sailing with Belbin
Authors: Watkins Bobby , Gibson‐Sweet Monica
Published: July 2002

Observes that a group of seven undergraduate consultancy project team members, studying in the final year of a business degree, greatly benefited from utilizing Meredith Belbin’s team role theory. Notes that Belbin’s approach was particularly useful in identifying strengths and weaknesses; enabling tasks to be allocated based on competence. Also that a method for retrospective analysis of the team’s performance was developed using Belbin’s framework. In some cases the perception of self differed significantly from the observed actions and behaviours. Points out that each team member completed Belbin’s psychometric test at the outset of the project and that these results were then tested through peer assessment at the end of the project, using a hypothetico‐deductive method. Uses an analogous framework to illustrate the level of cohesion and team role balance necessary for the team to perform effectively. Concludes that the learning potential of students can be maximized by enabling them to experience and reflect on the realities of team working for themselves.
Organizational commitment and job satisfaction as predictors of attitudes toward organizational change in a non‐western setting
Authors: Yousef Darwish A.
Published: July 2002

This study investigates the role of various dimensions of organizational commitment and job satisfaction in predicting various attitudes toward organizational change in a non‐western work setting. The study uses a sample of 474 employees in 30 organizations in the United Arab Emirates. Path analysis results reveal that employees’ affective and behavioral tendency attitudes toward organizational change increase with the increase in affective commitment, and that continuance commitment (low perceived alternatives) directly and negatively influences cognitive attitudes toward change. Results further show that affective commitment mediates the influences of satisfaction with working conditions, pay, supervision and security on both affective and behavioral tendency attitudes toward change. Continuance commitment (low perceived alternatives) mediates the influences of satisfaction with pay on cognitive attitudes toward change. Satisfaction with various facets of the job directly and positively influences different dimensions of organizational commitment. Implications, limitations and lines of future research are discussed.
Rover 75 sets new standards in body‐in‐white assembly
Authors: Rooks Brian
Published: July 2002

Highlights the investment made by Rover for the launch of its new executive car, the Rover 75. Discusses the reasoning behind the building of a completely new factory on the existing Oxford site that has double the output capacity of the one it replaces. It also has a much better quality potential, is very flexible and is designed for minimal environmental impact. Particular attention is given in the article to the new body‐in‐white facility, which sets new standards in robot automation and in the layout. These enable the plant to provide high productivity with a high degree of flexibility while meeting world‐class expectations equal to those of Rover’s owners, BMW.
The conservation of historic buildings in Britain and The Netherlands: a comparative study
Authors: Dann Nigel , Steel Mark
Published: July 2002

Britain and The Netherlands both have a large stock of historic buildings dating from pre‐Roman to modern. Both provide some degree of state funding and each has a series of national bodies that concern themselves with historic building preservation both by the allocation of grants and the awarding of special “listing” status. In both cases the creation of societies to protect historic buildings dates to the second half of the nineteenth century. Despite these similarities, there are substantive differences in the current approach to the preservation of historic buildings. In terms of government intervention The Netherlands employs a far more localised approach than is found in Britain. Tax deduction and government subsidies provide a substantial incentive to building maintenance in contrast to the British laissez faire approach. The private sector in The Netherlands also contrasts substantively with that of Britain. Most conservation work is undertaken by a relatively small number of large firms who belong to a close‐knit federation, in contrast to the British approach of a large number of small firms operating in a free market.
Finite strip method: 30 years A bibliography (1968‐1998)
Authors: Friedrich Richard
Published: July 2002

This bibliography contains references to papers, conference proceedings, theses and books dealing with finite strip, finite prism and finite layer analysis of structures, materially and/or geometrically linear or non‐linear.
Fixed grid finite elements in elasticity problems
Authors: García‐Ruíz M.J. , Steven G.P.
Published: July 2002

A fixed grid representation of the finite element domain is used to solve elasticity problems. An integration between CAD and FEM systems is made by using this fixed grid representation. Some considerations about FG approximation and stiffness matrix generation are presented. The element stiffness matrix for an element in the mesh is obtained as a factor of a standard element stiffness matrix. A least squares local approximation of stress field is used to calculate the stress at boundary elements. A problem with an analytical solution is used to measure the displacement and stress error. Several meshes and several geometrical configurations of the problem are used to test the reliability of the fixed grid finite element method.
A future for business simulations?
Authors: Fripp John
Published: July 2002

Business simulations have played an important part in management development activities for many years, but the world of business is changing fast and managers’ responsibilities are changing too. If simulations are to remain relevant they must keep abreast of these changes, and preferably anticipate them. Argues that while impressive “technical” developments have occurred in the design and use of business simulations over the last few years, other, rather different changes, have to take place or simulations will risk becoming increasingly irrelevant.