bluuebunny/crossref_metadata_2025 huggingface dataset:
Emerging antibiotic resistance in Salmonella Typhimurium in Norway
Authors: LEEGAARD T. M. , CAUGANT D. A. , FRØHOLM L. O. , HØIBY E. A. , LASSEN J.
Published: July 2002

The antimicrobial resistance of 809 Salmonella Typhimurium isolates collected from humans in
Norway between 1975 and 1998 was studied. The material was subdivided into domestic and
foreign isolates according to whether the patient had recently travelled abroad or not. In
imported isolates the largest increase in resistance was in 1996 when 35% of the isolates were
multi-resistant. The first multi-resistant isolate acquired in Norway appeared in 1994, but
already in 1998 23% of the isolates domestically acquired were multi-resistant, and a majority
were S. Typhimurium DT104. We found no ciprofloxacin resistance in domestically acquired
isolates. Amplified fragment length polymorphism analysis was performed on selected multi-resistant
isolates. The method discriminated well between different multi-resistant isolates, but
not between DT104 isolates. Resistant and multi-resistant S. Typhimurium were until 1998
essentially recovered from patients who had travelled abroad, but multi-resistant isolates,
mainly DT104, are now also being transmitted within the country.
The logic of causation and the risk of paralytic poliomyelitis
for an American child
Authors: RIDGWAY D.
Published: July 2002

Beginning in January 1997, American immunization policy allowed parents and physicians to
elect one of three approved infant vaccination strategies for preventing poliomyelitis. Although
the three strategies likely have different outcomes with respect to prevention of paralytic
poliomyelitis, the extreme rarity of the disease in the USA prevents any controlled comparison.
In this paper, a formal inferential logic, originally described by Donald Rubin, is applied to
the vaccination problem. Assumptions and indirect evidence are used to overcome the inability
to observe the same subjects under varying conditions to allow the inference of causality from
non-randomized observations. Using available epidemiologic information and explicit
assumptions, it is possible to project the risk of paralytic polio for infants immunized with oral
polio vaccine (1·3 cases per million vaccinees), inactivated polio vaccine (0·54 cases per million
vaccinees), or a sequential schedule (0·54–0·92 cases per million vaccinees).
On single interior spike solutions of the
Gierer–Meinhardt system:
uniqueness and spectrum estimates
Authors: WEI JUNCHENG
Published: July 2002

We study the interior spike solutions to a steady state problem of the shadow system of
the Gierer–Meinhardt system arising from biological pattern formation. We first show that
at a non-degenerate peak point the interior spike solution is locally unique, and then we
establish the spectrum estimates of the associated linearized operator. We also prove that the
corresponding solution to the shadow system is unstable. Furthermore, the metastability of
such solutions is analysed.
Red-black trees with types
Authors: KAHRS STEFAN
Published: July 2002

Chris Okasaki showed how to implement red-black trees in a functional programming
language. Ralf Hinze incorporated even the invariants of such data structures into their
types, using higher-order nested datatypes. We show how one can achieve something very
similar without the usual performance penalty of such types, by combining the features of
nested datatypes, phantom types and existential type variables.
A radical view of immunosenescence: Does chronic redox depletion interfere with immune cell signalling and function?
Authors: Rider David A. , Young Stephen P.
Published: July 2002

Many changes occur in the aging immune system, which culminate in its functional decline, but the underlying mechanisms have proved difficult to define. Wick and Grubeck-Loebenstein have recently classified the changes in function as either primary ‘those that occur in perfectly healthy older individuals’ as the result of ‘an age dependent intrinsic decline of immune responsiveness’ or secondary ‘those that are due to underlying disease or various environmental factors including diet, drug intake, physical activity, etc’. Both types of alteration are important when considering immune dysfunction in older people which seems to be centred on the loss of cell-mediated immunity, in particular the activity of CD4 helper T lymphocytes.
Have geriatricians lost their way in rehabilitation and long-term care?
Authors: MacMahon Doug
Published: July 2002

Geriatric medicine started in long-term care, when the pioneers in the emerging specialty examined the inhabitants of the Victorian workhouses to discover elderly, largely ignored, yet eminently treatable patients. They focused attention on the then taboo subjects of incontinence, dementia and immobility. They developed a paradigm which entailed a proper assessment and, where appropriate, rehabilitation. This empirical process was central to their evident success, and achieved a reduction in unnecessary institutionalization by restricting long-stay care to those who could not, after full assessment and treatment, be discharged. The concept of progressive patient care developed, to make best use of somewhat meagre facilities. Day hospitals spread nationally, and outreach teams developed. Respite care schemes provided support to the huge numbers of informal carers, by sharing the load with the hospital service.
An axiomatization of partial n-place operations
Authors: FORTI MARCO , HONSELL FURIO , LENISA MARINA
Published: July 2002

We propose a general theory of partial n-place operations
based solely on the primitive
notion of the application of a (possibly partial) operation to n objects.
This theory is strongly
selfdescriptive in that the fundamental manipulations of operations, that
is,
application,
composition, abstraction, union, intersection
and so on, are themselves internal operations. We
give several applications of this theory, including implementations of
partial
n-ary
λ-calculus, and other operation description languages. We investigate
the issue of
extensionality and give weakly extensional models of
the theory.
Premonoidal categories and notions of computation
Authors: POWER JOHN , ROBINSON EDMUND
Published: July 2002

We introduce the notions of premonoidal category and premonoidal
functor, and show how
these can be used in the denotational semantics of programming languages.
We characterize
the semantic definitions of Eugenio Moggi's monads as notions of
computation, exhibit a
representation theorem for our premonoidal setting in terms of monads,
and give a
fibrational setting for the structure.
A general method for proving the normalization
theorem for first and second order typed λ-calculi
Authors: CAPRETTA VENANZIO , VALENTINI SILVIO
Published: July 2002

In this paper we describe a method for proving the normalization property for a large
variety of typed lambda calculi of first and second order, which is based on a proof of
equivalence of two deduction systems. We first illustrate the method on the elementary
example of simply typed lambda calculus, and then we show how to extend it to a more
expressive dependent type system. Finally we use it to prove the normalization theorem for
Girard's system F.
The Greening of Bioethics: Corporate Funding of Bioethics
Research
Authors: TURNER LEIGH
Published: July 2002

Bioethicists recognize the conflicts of interest
that can arise for clinicians and scientists. However,
few scholars exploring the moral dimensions of medicine
and the sciences publicly address potential conflicts of
interest concerning their own research. Increasingly, however,
bioethicists will be confronted with difficult choices
in which opportunities to obtain funding will sometimes
conflict with the pursuit of critical, rigorous scholarship
conducted without regard for corporate interests.
Mass Pre-Embryo Adoption
Authors: DEMARTIS FRANCESCO
Published: July 2002

On August 1, 1996, due to the expiration of the
five-year preservation limit provided by British law for
unclaimed and legally unusable frozen embryos, 3,300 embryos
were thawed and discarded. In Italy the news of this
impending event triggered many reactions among scholars
as well as the general population. In Massa, a little
town in Tuscany, a most unusual response arose.
Two hundred women banded together and asked to carry out
a prenatal adoption. Their purpose in making this request
was to avoid what they believed to be mass infanticide.
Many of the women were married and already had children.
They belonged to a local Catholic association. Nonetheless,
their reaction was their own response to numerous appeals
to respect life by the Catholic Church worldwide and by
Italian Catholic thinkers especially.
Dynamic changes of the microtubule system corresponding to the unequal and spiral cleavage modes in the embryo of the zebra mussel, Dreissena polymorpha (Mollusca, Bivalvia)
Authors: Luetjens Craig Marc , Dorresteijn Adriaan W.C.
Published: July 2002

Unequal cleavage requires a highly organised cytoskeleton. We investigated the localisation of both tubulins and microtubular arrays in Dreissena eggs during and after fertilisation using confocal laser scanning microscopy. Freshly spawned eggs are arrested in metaphase I. A maternal pool of γ-tubulin is found mainly in the centre of the asters of the meiotic spindle. The paternal pool of γ-tubulin, present in the fertilising sperm, could not be traced within the egg, but a microtubule-organising centre forms near the male pronucleus at anaphase II. Male and female pronuclei grow as they migrate in the wake of their aster and rendezvous. First cleavage is unequal and starts without pronuclear fusion. At metaphase the two equal-sized asters span the entire egg in a symmetrical arrangement. At late metaphase the spindle shifts along its longitudinal axis into an eccentric position and the peripheral aster takes on an umbrella-like appearance, whereas the central aster remains spherical. The cleavage furrow becomes determined in the circumferential overlap of the asters. The inequality at second cleavage, however, is due to the unequal size of the asters. The third cleavage spindle also has asymmetrical asters and spindle shift was only observed in the D-cell. The spiral character is a result of an asymmetrical organisation of the larger, vegetal aster. Our results show that the arrangement of the γ-tubulin clusters and of microtubules changes and develops during early development of Dreissena in a way that can explain the axis-generating asymmetries in cell pattern and the spiral sense of cleavage. The major cytological characters expected to direct pattern formation in this phase of development are: size, position, and symmetry or asymmetry of both spindle and asters.
The LiLFeS Abstract Machine and
its evaluation with the LinGO grammar
Authors: MIYAO YUSUKE , MAKINO TAKAKI , TORISAWA KENTARO , TSUJII JUN-ICHI
Published: July 2002

This article evaluates the efficiency of the LiLFeS abstract machine by performing parsing
tasks with the LinGO English resource grammar. The instruction set of the abstract machine
is optimized for efficient processing of definite clause programs and typed feature structures.
LiLFeS also supports various tools required for efficient parsing (e.g. efficient copying, a
built-in CFG parser) and the constructions of standard Prolog (e.g. cut, assertions, negation
as failure). Several parsers and large-scale grammars, including the LinGO grammar, have
been implemented in or ported to LiLFeS. Precise empirical results with the LinGO grammar
are provided to allow comparison with other systems. The experimental results demonstrate
the efficiency of the LiLFeS abstract machine.
A lexicalist approach towards the automatic determination for the syntactic functions of prepositional phrases
Authors: CHENGYU FANG ALEX
Published: July 2002

Prepositional Phrases (PP) perform a variety of syntactic functions in a conventional sentence,
and cause severe problems to computer systems that automatically analyse the sentential syntax.
A major issue in this area has been the automatic determination of the syntactic functions
of PPs. Most work published so far makes use of the probabilistic approach, and attach PPs
to either the antecedent noun or verb phrase. Due to the natural limitation of the probabilistic
approach, it is important to evaluate the linguistic behaviour of prepositional phrases and
propose qualitative solutions to the problem. In this article, I first provide a detailed account
of statistics regarding the frequency of use for (i) types of prepositions, (ii) syntactic categories
as realisations of prepositional complements, and (iii) the syntactic functions of prepositional
phrases. Statistics reported here all derive from a representative corpus of contemporary
British English. I then describe a set of rules that has been implemented in order to label
PPs automatically for their syntactic functions. I finally report on the coverage of these rules
empirically observed in an experiment which involved a set of naturally occurring PPs as test
data.
TextNet – A text-based intelligent system
Authors: HARABAGIU SANDA M. , MOLDOVAN DAN I.
Published: July 2002

A large collection of texts may be reached through the Internet

and this provides a powerful
platform from which common-sense knowledge may be gathered. This paper
presents a system
that contains a core knowledge base structured around WordNet, a lexical
database, capable
of extracting contextual information from a given input text. Such context
information is
then used to retrieve other texts from the Internet that relate to that
context. When processed
by the system, these new texts bring more information that represents an
enhanced domain
context for the initial text. This is an incremental method for text processing
that acquires
domain knowledge from other texts. The paper describes the system architecture,
its core
knowledge base and inference engine, and the acquisition of new knowledge
from corpora.
Cognitive decline in patients with Cushing's syndrome
Authors: FORGET HÉLÈNE , LACROIX ANDRÉ , SOMMA MAURICE , COHEN HENRI
Published: July 2002

Because the corresponding author was out of the office on business,
corrections could not be made to Table 2 that appeared in JINS,
6:1, p. 24. In the table footnote, for F = 6.39, the
degree of freedom should have been added: df = 1,36.
Use of the Disability Rating Scale recovery curve as a predictor
of psychosocial outcome following closed-head injury
Authors: McCAULEY STEPHEN R. , HANNAY H. JULIA , SWANK PAUL R.
Published: July 2002

Rapid rate of recovery has been associated with better
outcome following closed-head injuries, but few studies
have compellingly demonstrated this. This study used growth
curve analyses of Disability Rating Scale (DRS) scores
at acute hospitalization discharge, 1, 3, and 6 months
post injury in a sample of 55 patients with a closed-head
injury. Six month post-injury outcome measures were taken
from significant other (SO) responses on the NYU Head Injury
Family Interview (NYU-HIFI) including severity and burden
ratings of affective/neurobehavioral disturbance, cognitive
deficits, and physical/dependency status. Rate of recovery
(linear and curvilinear recovery curve components) was
significantly related to the level of affective/neurobehavioral
severity, and the severity and burden of SO-perceived cognitive
deficits. Only the intercept of the DRS recovery curve
was associated with the SO-perceived severity and burden
of physical/dependency status. Growth curve modeling is
a meaningful and powerful tool in predicting head injury
outcome. (JINS, 2001, 7, 457–467.)
Quasi-option value and hard uncertainty
Authors: BASILI MARCELLO
Published: July 2002

The notion of intertemporal h-option value is introduced to extend to environmental decision-making problems of the concept of quasi-option value, defined by Arrow and Fisher and Henry, whenever an individual faces imprecise information, or hard uncertainty, represented by a non-additive measure over events. Under hard uncertainty and irreversibility, the decision-maker faces the intertemporal h-option value, that is an uncertainty premium of preservation, which represents the gain from being able to learn about the future consequences of irreversible actions. The intertemporal h-option value is a correction factor that has to be taken into account in evaluating the total economic value of feasible actions.
Applying economic instruments in developing countries: from theory to implementation
Authors: O'CONNOR DAVID
Published: July 2002

The paper describes a number of developing country applications of economic instruments (EIs), focusing on how policy makers—mostly in Asia and La
tin America—have addressed implementation problems. The informational and institutional demands of EIs can be as great as with regulations; in any event, the former are mostly used to complement not replace the latter. Consideration of political acc
eptability has conditioned both instrument design (e.g. grandfathering of tradable permits, non-compliance fees rather than simple pollution charges) and phasing of implementation (e.g. starting with local experimentation, setting low initial charge rates). With the advance of market-oriented economic reforms in the developing world, the policy and institutional environment should become more conducive to applying EIs; with greater political openness in many countries, the scope for involving the media, n
on-governmental organizations, and the public at large in environmental enforcement (e.g., through information disclosure programmes) should also increase.
Ian Fredericks in interview: ideas of an Australian spatial synthesis and mixed media innovator
Authors: Lyons Andrew D.
Published: July 2002

Ian Fredericks played a prominent role in the development of Australian electronic music and mixed media composition
from the mid 1970s until 2001. His work in establishing both the SEUSS electronic music studio at Sydney University
and the subsequent founding of the computer music and audio-visual composition and performance group watt with
Martin Wesley-Smith in 1976, paved the way for the generations of artists that have since explored this field. The
author presents lightly edited excerpts from the last interview with Ian Fredericks before his passing on 15 March
2001.
Exaggeration of Symptoms or Psychiatric Munchausen's Syndrome by Proxy?
Authors: McNicholas Fiona , Slonims Vicky , Cass Hilary
Published: July 2002

Prompt and accurate diagnosis of Munchausen's syndrome by proxy is
essential in order to minimise the risk of iatrogenic and parentally-induced
harm to the child. However, inaccurate diagnosis of MSBP may have
devastating consequences for the child, family and professionals involved.
‘Psychiatric’ Munchausen's syndrome by proxy, which involves the
presentation of signs and symptoms suggestive of a psychiatric disorder in
the child, is even more difficult to diagnose and requires an unbiased and
full assessment by the appropriate multidisciplinary team.
A New Government – A New Democracy? The Red–Green Coalition in Germany
Authors: Kaase Max
Published: July 2002

With the 1989 eclipse of communist ideology and power in Central and Eastern Europe, the political order of democracy has, on the one hand, proved to be the superior way of organizing a society where in politics the pluralist interests of the people can be articulated and represented freely without fear of repression through competitive elections and otherwise, and where particularly through the operation of market mechanisms citizens are furnished with reasonably satisfactory economic circumstances to conduct their everyday lives. On the other hand, quite different from what many contemporary observers had anticipated, liberal democracy has been subjected to closer and closer critical internal scrutiny, and with this also alternate conceptions of how to organize a democratic polity are now more than before a matter of debate and controversy.
hMSH3 and hMSH6 interact with PCNA and colocalize with it to replication foci
Authors: Kleczkowska Hanna E. , Marra Giancarlo , Lettieri Teresa , Jiricny Josef
Published: July 2002

Proliferating cell nuclear antigen (PCNA) has been implicated in eukaryotic postreplicative mismatch correction, but the nature of its interaction with the repair machinery remained enigmatic. We now show that PCNA binds to the human mismatch binding factors hMutSα and hMutSβ via their hMSH6 and hMSH3 subunits, respectively. The N-terminal domains of both proteins contain the highly conserved PCNA-binding motif Qxx[LI]xx[FF]. A variant of hMutSα, lacking this motif because of deletion of 77 N-terminal residues of the hMSH6 subunit, no longer was able to interact with PCNA in vitro and failed to restore mismatch repair in hMSH6-deficient cells. Colocalization of PCNA and hMSH6 or hMSH3 to replication foci implies an intimate link between replication and mismatch correction. We postulate that PCNA plays a role in repair initiation by guiding the mismatch repair proteins to free termini in the newly replicated DNA strands.
Unipolar membrane association of Dishevelled mediates Frizzled planar cell polarity signaling
Authors: Axelrod Jeffrey D.
Published: July 2002

Drosophila epithelia acquire a planar cell polarity (PCP) orthogonal to their apical-basal axes. Frizzled (Fz) is the receptor for the PCP signal, and Dishevelled (Dsh) transduces the signal. Here, I demonstrate that unipolar relocalization of Dsh to the membrane is required to mediate PCP, but not Wingless (Wg) signaling. Dsh membrane localization reflects the activation of Fz/PCP signaling, revealing that the initially symmetric signal evolves to one that displays unipolar asymmetry, specifying the cells' ultimate polarity. This transition from symmetric to asymmetric Dsh localization requires Dsh function, and reflects an amplification process that generates a steep intracellular activity gradient necessary to determine PCP.
The hairless gene mutated in congenital hair loss disorders encodes a novel nuclear receptor corepressor
Authors: Potter Gregory B. , Beaudoin Gerard M.J. , DeRenzo Cynthia L. , Zarach Joanna M. , Chen Steve H. , Thompson Catherine C.
Published: July 2002

The mammalian hairless (hr) gene plays a critical role in the maintenance of hair growth. Although the hr gene has been identified, the biochemical function of its encoded protein (Hr) has remained obscure. Here, we show that Hr functions as a transcriptional corepressor for thyroid hormone receptors (TRs). We find that two independent regions of Hr mediate TR binding and that interaction requires a cluster of hydrophobic residues similar to the binding motifs proposed for nuclear receptor corepressors (N-CoR and SMRT). Similarly, we show that Hr binds to the same region of TR as known corepressors. We show that Hr interacts with histone deacetylases (HDACs) and is localized to matrix-associated deacetylase (MAD) bodies, indicating that the mechanism of Hr-mediated repression is likely through associated HDAC activity. Thus, Hr is a component of the corepressor machinery, and despite its lack of sequence identity with previously described corepressors, its mode of action is remarkably conserved. On the basis of its thyroid hormone-inducible and tissue- and developmental-specific expression, Hr likely defines a new class of nuclear receptor corepressors that serve a more specialized role than ubiquitous corepressors. The discovery that Hr is a corepressor provides a molecular basis for specific hair loss syndromes in both humans and mice.
HEAT Repeats Associated with Condensins, Cohesins, and Other Complexes Involved in Chromosome-Related Functions
Authors: Neuwald Andrew F. , Hirano Tatsuya
Published: July 2002

HEAT repeats correspond to tandemly arranged curlicue-like structures that appear to serve as flexible scaffolding on which other components can assemble. Using sensitive sequence analysis techniques we detected HEAT repeats in various chromosome-associated proteins, including four families of proteins associated with condensins and cohesins, which are nuclear complexes that contain structural maintenance of chromosome (SMC) proteins. Among the proteins detected were the XCAP-D2 and XCAP-G subunits of the Xenopus laevis 13S condensin complex, the Aspergillus BimD and Sordaria macrospora Spo76p proteins, the budding yeast Scc2p protein, and the related Drosophila transcriptional activator Nipped-B. Clathrin adaptor and COP-I coatomer subunits, which function in vesicle coat assembly and were previously noted to share weak sequence similarity to condensin subunits, also contain HEAT repeats. HEAT repeats were also found in the TBP-associated TIP120 protein, a global enhancer of transcription, and in the budding yeast Mot1p protein, which is a member of the SWI2/SNF2 family. SWI2/SNF2 proteins, some of which are helicases, perform diverse roles in transcription control, DNA repair, and chromosome segregation and form chromatin-remodeling complexes. HEAT repeats also were found in dis1-TOG family and cofactor D family microtubule-associated proteins, which, owing to their roles in microtubule dynamics, perform functions related to mitotic progression and chromosome segregation. Hence, our analysis predicts structural features of these proteins and suggests that HEAT repeats may play important roles in chromosome dynamics.
The Family of Caenorhabditis elegans Tyrosine Kinase Receptors: Similarities and Differences with Mammalian Receptors
Authors: Popovici Cornel , Roubin Régine , Coulier François , Pontarotti Pierre , Birnbaum Daniel
Published: July 2002

Transmembrane receptors with tyrosine kinase activity (RTK) constitute a superfamily of proteins present in all metazoans that is associated with the control and regulation of cellular processes. They have been the focus of numerous studies and are a good subject for comparative analyses of multigene families in different species aimed at understanding metazoan evolution. The sequence of the genome of the nematode worm Caenorhabditis elegans is available. This offers a good opportunity to study the superfamily of nematode RTKs in its entirety and to compare it with its mammalian counterpart. We show that the C. elegans RTKs constitute various groups with different phylogenetic relationships with mammalian RTKs. A group of four RTKs show structural similarity with the three mammalian receptors for the vascular endothelial growth factors. Another group comprises RTKs with a short extracellular region, a feature not known in mammals; the genes encoding these RTKs are clustered on chromosome II with other gene families, including genes encoding chitinase-like proteins. Most of theC. elegans RTKs have no direct orthologous relationship with any mammalian RTK, providing an illustration of the importance of the separate evolution of the different phyla.

[The sequences in this paper have been submitted to GenBank under the following accession numbers: AF188748, AF188749, AF188750, and AF188751.]
Tissue Localization of a Submergence-Induced 1-Aminocyclopropane-1-Carboxylic Acid Synthase in Rice
Authors: Zhou Zhongyi , de Almeida Engler Janice , Rouan Dominique , Michiels Frank , Van Montagu Marc , Van Der Straeten Dominique
Published: July 2002

At least two 1-aminocyclopropane-1-carboxylic acid synthase genes (ACS) are implicated in the submergence response of rice (Oryza sativa). Previously, theOS-ACS5 gene has been shown to be induced during short- as well as long-term complete submergence of seedlings and to be controlled by a balance of gibberellin and abscisic acid in both lowland and deepwater rice. This study demonstrates thatOS-ACS5 mRNA is localized in specific tissues and cells both during normal development and in response to complete submergence. The temporal and spatial regulation of OS-ACS5expression is presented by in situ hybridization and histochemical analysis of β-glucuronidase (GUS) activity in transgenic rice carrying an OS-ACS5-gus fusion. Whole-mount in situ hybridization revealed that in air-grown rice seedlings,OS-ACS5 was expressed at a low level in the shoot apex, meristems, leaf, and adventitious root primordia, and in vascular tissues of nonelongated stems and leaf sheaths. In response to complete submergence, the expression in vascular bundles of young stems and leaf sheaths was strongly induced. The results of histochemical GUS assays were consistent with those found by whole-mount in situ hybridization. Our findings suggest that OS-ACS5 plays a role in vegetative growth of rice under normal conditions and is also recruited for enhanced growth upon complete submergence. The possible implication of OS-ACS5 in root-shoot communication during submergence stress and its putative role in aerenchyma formation upon low-oxygen stress are discussed.
Regulation of the Cell Expansion Gene RHD3 during Arabidopsis Development
Authors: Wang Haiyang , Lee Myeong Min , Schiefelbein John W.
Published: July 2002

The RHD3 (ROOT HAIR DEFECTIVE3) gene encodes a putative GTP-binding protein required for appropriate cell enlargement in Arabidopsis. To obtain insight into the mechanisms of RHD3 regulation, we conducted a molecular genetic dissection of RHD3 gene expression and function. Gene fusion and complementation studies show that the RHD3 gene is highly expressed throughout Arabidopsis development and is controlled by two major regulatory regions. One regulatory region is located between −1,500 and −600 bp upstream of the RHD3 gene and is required for vascular tissue expression. The other region is intragenically located and includes the 558-bp first intron, which is responsible for high-level expression of RHD3 throughout the plant. The presence and location of this intron is essential for gene function because constructs lacking this intron or constructs with the intron in an abnormal position are unable to functionally complement therhd3 mutations. We also analyzed the role of otherRHD genes and the plant hormones auxin and ethylene inRHD3 regulation, and we determined that these act downstream or independently from the RHD3 pathway. This study shows that multiple levels of regulation are employed to ensure the appropriate expression of RHD3 throughout Arabidopsis development.
Adaptation of H+-Pumping and Plasma Membrane H+ ATPase Activity in Proteoid Roots of White Lupin under Phosphate Deficiency
Authors: Yan Feng , Zhu Yiyong , Müller Caroline , Zörb Christian , Schubert Sven
Published: July 2002

White lupin (Lupinus albus) is able to adapt to phosphorus deficiency by producing proteoid roots that release a huge amount of organic acids, resulting in mobilization of sparingly soluble soil phosphate in rhizosphere. The mechanisms responsible for the release of organic acids by proteoid root cells, especially the trans-membrane transport processes, have not been elucidated. Because of high cytosolic pH, the release of undissociated organic acids is not probable. In the present study, we focused on H+ export by plasma membrane H+ ATPase in active proteoid roots. In vivo, rhizosphere acidification of active proteoid roots was vanadate sensitive. Plasma membranes were isolated from proteoid roots and lateral roots from P-deficient and -sufficient plants. In vitro, in comparison with two types of lateral roots and proteoid roots of P-sufficient plants, the following increase of the various parameters was induced in active proteoid roots of P-deficient plants: (a) hydrolytic ATPase activity, (b) V  max andK  m, (c) H+ ATPase enzyme concentration of plasma membrane, (d) H+-pumping activity, (e) pH gradient across the membrane of plasmalemma vesicles, and (f) passive H+ permeability of plasma membrane. In addition, lower vanadate sensitivity and more acidic pH optimum were determined for plasma membrane ATPase of active proteoid roots. Our data support the hypothesis that in active proteoid root cells, H+ and organic anions are exported separately, and that modification of plasma membrane H+ ATPase is essential for enhanced rhizosphere acidification by active proteoid roots.
Gene Structure and Differential Regulation of the Rhizobium-Induced Peroxidase Gene rip1
Authors: Peng H. M. , Dreyer D. A. , VandenBosch K. A. , Cook D.
Published: July 2002

Primary expression of the Rhizobium meliloti-induced peroxidase gene rip1 occurs prior to nodule morphogenesis, specifically at the site of impending rhizobial infection (D. Cook, D. Dreyer, D. Bonnet, M. Howell, E. Nony, K. VandenBosch [1995] Plant Cell 7:43–55). We examined the distribution and structure of rip1 transcript throughout nodule development. We determined that expression of rip1 in root tips is correlated with the competence of this zone for symbiotic association, whereas after rhizobial infection rip1 transcript is specifically associated with the zone of nodule development, including nascent nodule primordia. rip1 transcripts are characterized by multiple polyadenylation sites distributed within 200 to 400 bp of the translation stop site, and a single major transcription initiation site in close proximity to the rip1 open reading frame. Thus, rip1 expression is likely to be mediated through effects on a single transcription unit. Immediately 5[prime] of the rip1 transcription unit DNA sequence analysis identified a 377-bp DNA element containing extensive repeat structure that is widely distributed in the Medicago truncatula genome.
The Role of Iron-Deficiency Stress Responses in Stimulating Heavy-Metal Transport in Plants1
Authors: Cohen Clara K. , Fox Tama C. , Garvin David F. , Kochian Leon V.
Published: July 2002

Plant accumulation of Fe and other metals can be enhanced under Fe deficiency. We investigated the influence of Fe status on heavy-metal and divalent-cation uptake in roots of pea (Pisum sativum L. cv Sparkle) seedlings using Cd2+ uptake as a model system. Radiotracer techniques were used to quantify unidirectional 109Cd influx into roots of Fe-deficient and Fe-sufficient pea seedlings. The concentration-dependent kinetics for 109Cd influx were graphically complex and nonsaturating but could be resolved into a linear component and a saturable component exhibiting Michaelis-Menten kinetics. We demonstrated that the linear component was apoplastically bound Cd2+ remaining in the root cell wall after desorption, whereas the saturable component was transporter-mediated Cd2+ influx across the root-cell plasma membrane. The Cd2+ transport system in roots of both Fe-deficient and Fe-sufficient seedlings exhibited similar Michaelis constant values, 1.5 and 0.6 μm, respectively, for saturable Cd2+ influx, whereas the maximum initial velocity for Cd2+ uptake in Fe-deficient seedlings was nearly 7-fold higher than that in Fe-grown seedlings. Investigations into the mechanistic basis for this response demonstrated that Fe-deficiency-induced stimulation of the plasma membrane H+-ATPase did not play a role in the enhanced Cd2+ uptake. Expression studies with the Fe2+transporter cloned from Arabidopsis, IRT1, indicated that Fe deficiency induced the expression of this transporter, which might facilitate the transport of heavy-metal divalent cations such as Cd2+ and Zn2+, in addition to Fe2+.
Shifts of Intracellular pH Distribution as a Part of the Signal Mechanism Leading to the Elicitation of Benzophenanthridine Alkaloids
Authors: Roos Werner , Evers Sven , Hieke Margit , Tschöpe Markus , Schumann Brigitte
Published: July 2002

Cultured cells ofEschscholtzia californica (Californian poppy) respond to a yeast elicitor preparation or Penicillium cyclopiumspores with the production of benzophenanthridine alkaloids, which are potent phytoalexins. Confocal pH mapping with the probe carboxy-seminaphthorhodafluor-1-acetoxymethylester revealed characteristic shifts of the pH distribution in challenged cells: within a few minutes after elicitor contact a transient acidification of cytoplasmic and nuclear areas occurred in parallel with an increase of the vacuolar pH. The change of proton concentration in the vacuole and in the extravacuolar area showed a nearly constant relation, indicating an efflux of vacuolar protons into the cytosol. A 10-min treatment with 2 mm butyric or pivalic acid caused a transient acidification of the cytoplasm comparable to that observed after elicitor contact and also induced alkaloid biosynthesis. Experimental depletion of the vacuolar proton pool reversibly prevented both the elicitor-triggered pH shifts and the induction of alkaloid biosynthesis. pH shifts and induction of alkaloid biosynthesis showed a similar dependence on the elicitor concentration. Net efflux of K+, alkalinization of the outer medium, and browning of the cells were evoked only at higher elicitor concentrations. We suggest that transient acidification of the cytoplasm via efflux of vacuolar protons is both a necessary and sufficient step in the signal path toward biosynthesis of benzophenanthridine alkaloids in Californian poppy cells.
Aluminum-Induced 1→3-β-d-Glucan Inhibits Cell-to-Cell Trafficking of Molecules through Plasmodesmata. A New Mechanism of Aluminum Toxicity in Plants
Authors: Sivaguru Mayandi , Fujiwara Toru , Šamaj Josef , Baluška František , Yang Zhenming , Osawa Hiroki , Maeda Takanori , Mori Tomoko , Volkmann Dieter , Matsumoto Hideaki
Published: July 2002

Symplastic intercellular transport in plants is achieved by plasmodesmata (PD). These cytoplasmic channels are well known to interconnect plant cells to facilitate intercellular movement of water, nutrients, and signaling molecules including hormones. However, it is not known whether Al may affect this cell-to-cell transport process, which is a critical feature for roots as organs of nutrient/water uptake. We have microinjected the dye lucifer yellow carbohydrazide into peripheral root cells of an Al-sensitive wheat (Triticum aestivum cv Scout 66) either before or after Al treatment and followed the cell-to-cell dye-coupling through PD. Here we show that the Al-induced root growth inhibition is closely associated with the Al-induced blockage of cell-to-cell dye coupling. Immunofluorescence combined with immuno-electron microscopic techniques using monoclonal antibodies against 1→3-β-d-glucan (callose) revealed circumstantial evidence that Al-induced callose deposition at PD may responsible for this blockage of symplastic transport. Use of 2-deoxy-d-glucose, a callose synthesis inhibitor, allowed us to demonstrate that a reduction in callose particles correlated well with the improved dye-coupling and reduced root growth inhibition. While assessing the tissue specificity of this Al effect, comparable responses were obtained from the dye-coupling pattern in tobacco (Nicotiana tabacum) mesophyll cells. Analyses of the Al-induced expression of PD-associated proteins, such as calreticulin and unconventional myosin VIII, showed enhanced fluorescence and co-localizations with callose deposits. These results suggest that Al-signal mediated localized alterations to calcium homeostasis may drive callose formation and PD closure. Our data demonstrate that extracellular Al-induced callose deposition at PD could effectively block symplastic transport and communication in higher plants.
Direct Evidence of Active and Rapid Nuclear Degradation Triggered by Vacuole Rupture during Programmed Cell Death in Zinnia
Authors: Obara Keisuke , Kuriyama Hideo , Fukuda Hiroo
Published: July 2002

Differentiation into a tracheary element (TE) is a typical example of programmed cell death (PCD) in the developmental processes of vascular plants. In the PCD process the TE degrades its cellular contents and becomes a hollow corpse that serves as a water conduct. Using a zinnia (Zinnia elegans) cell culture we obtained serial observations of single living cells undergoing TE PCD by confocal laser scanning microscopy. Vital staining was performed and the relative fluorescence intensity was measured, revealing that the tonoplast of the swollen vacuole in TEs loses selective permeability of fluorescein just before its physical rupture. After the vacuole ruptured the nucleus was degraded rapidly within 10 to 20 min. No prominent chromatin condensation or nuclear fragmentation occurred in this process. Nucleoids in chloroplasts were also degraded in a similar time course to that of the nucleus. Degradations did not occur in non-TEs forced to rupture the vacuole by probenecid treatment. These results demonstrate that TE differentiation involves a unique type of PCD in which active and rapid nuclear degradation is triggered by vacuole rupture.
The application of virtual prototyping in the development of complex aerospace products
Authors: Bennett G.R.
Published: July 2002

Highlights that the application of virtual prototyping to the development of complex aerospace products has brought about a revolution in the way that such products are introduced into production. Deals with implications of the introduction of virtual prototyping to a highly competitive high‐technology global industry. Points out that the benefits of this engineering innovation are not limited to the aerospace sector, however, and the lessons learned can be equally applied in other design and manufacturing activities. Describes the development and application of a comprehensive virtual prototyping initiative applied to the mechanical design and manufacture domain at British Aerospace Defence Dynamics, and the extent to which it has affected working practice. Introduces aspects of the existing research collaboration programme, and identifies potential areas for future research.
A comparative analysis of wine reviews
Authors: Chaney Isabella M.
Published: July 2002

This article focuses on the efforts of wine journalists to disseminate information. A content analysis is undertaken of articles in specialist wine magazines and weekend newspapers. This analysis is in the form of a comparative study based on the wine information for the three southern hemisphere countries of Australia, South Africa and New Zealand. When amount of column space devoted to each is assessed, it is evident that New Zealand, the smallest wine producing country of the three, is more positively favoured receiving a disproportionate amount of attention. However, an analysis of the information disseminated questions the value of the reviews.
Academic leaders: made or born?
Authors: Rowley Jennifer
Published: July 2002

Leadership is essential in all organizations and educational institutions are no exception, but the concept of academic leadership is unique in higher education and, arguably, is concerned with leadership that extends beyond the organization into the wider world that higher education institutions seek to serve. Traditional concepts of academic leadership are closely associated with individual excellence. Explores the importance of the contingency model of leadership, which suggests that leadership style might change to accommodate changing and differing environments. The way in which teams function in higher education could be closely matched with the concept of the self‐directed team. The concept of the learning organization as an organization which knows how to transform itself to meet changing circumstances defines specific roles for leaders.
Theory, training and technology: part I
Authors: Wood David
Published: July 2002

The range of potential applications of IT to education and training
is so vast that it can hardly be envisaged. Theories of learning and
instruction should be able to provide a framework to enable us to search
this space of possibilities and to assess some of the potential uses of
the technology. Part I outlines these theories and considers their
principal implications for the role of educational technology to support
instruction and learning. In part II, examples of systems which have
been inspired by these theories will be examined.
“Winners” training and its troubles
Authors: Stein Mark
Published: July 2002

The concept of “winners” has become a popular motif in the design of training programmes, especially in the area of customer service. This paper examines the case of one such training programme at “CapitalAirport”, with the purpose of understanding how the “winners” idea was experienced by employees, and exploring the implications that follow from this. The paper applies psychoanalytic concepts in the analysis of the findings, proposing that important functions of management may be analogically compared to the mother‐infant relationship. The findings suggest that the “winners” idea was experienced by employees as a denial of the truth and as involving the imposition of a distorted and dishonest image on to their work. The idea was also felt to provoke considerable envy and jealousy among the workforce. This experience was associated with unfortunate consequences for learning and development.
Climbing, walking and intervention robots
Authors: Armada Manuel , Gonzalez de Santos Pablo
Published: July 2002

Explains how the Automatic Control Department of the Instituto de Automatica Industrial (CSIC) in Madrid, Spain has been developing robots for over 15 years. This activity began in the 1980s with the realization of industrial robots and then the department focused its attention on the area of robots for hostile/hazardous environments. Describes several achievements in this field including a complex tele‐operated system for steam generator inspection and maintenance in nuclear power plants; a tele‐manipulator for servicing a new concept of urban infrastructures; a self‐propelling climbing robot with magnetic feet; and a four‐legged walking robot for hazardous environments.
Teamwork in health care
Authors: Ingram Hadyn , Desombre Terry
Published: July 2002

It is becoming more difficult to provide health care that meets the needs of patients within tight budget constraints. This article suggests that one way forward is to channel the energies of people more constructively to work as teams. Some definitions are shown for teams and teamwork, and four benefits suggested of effective teamwork: learning and development, resource management, task performance and communications. In each of these four areas, examples are given from the international world of health care of how teamwork can be achieved. Finally, it is concluded that teamwork can be difficult, but that it is worth pursuing.
Comparison of quasi minimal residual and bi‐conjugate gradient iterative methods to solve complex symmetric systems arising from time‐harmonic magnetic simulations
Authors: De Gersem H. , Lahaye D. , Vandewalle S. , Hameyer K.
Published: July 2002

Finite element discretizations of low‐frequency, time‐harmonic magnetic problems lead to sparse, complex symmetric systems of linear equations. The question arises which Krylov subspace methods are appropriate to solve such systems. The quasi minimal residual method combines a constant amount of work and storage per iteration step with a smooth convergence history. These advantages are obtained by building a quasi minimal residual approach on top of a Lanczos process to construct the search space. Solving the complex systems by transforming them to equivalent real ones of double dimension has to be avoided as such real systems have spectra that are less favourable for the convergence of Krylov‐based methods. Numerical experiments are performed on electromagnetic engineering problems to compare the quasi minimal residual method to the bi‐conjugate gradient method and the generalized minimal residual method.
A new collision detection algorithm for garment animation
Authors: Stylios G. , Wan T.R.
Published: July 2002

This paper presents a new technique for collision detection between fabric and fabric or fabric and body, applied on our physical‐based fabric drape model. The technique can produce a realistic 3D virtual fashion show based on fabric mechanical properties and has the ability to handle the collision of clothing with an animated synthetic human. The collision technique appeared efficient and reliable when dealing with complex cases of fabric deformation. A full implementation of the drape model, collision detection with an animated human model is also described and discussed.