bluuebunny/crossref_metadata_2025 huggingface dataset:
Emetic toxin formation of Bacillus cereus is restricted to a single evolutionary lineage of closely related strains
Authors: Ehling-Schulz Monika , Svensson Birgitta , Guinebretiere Marie-Helene , Lindbäck Toril , Andersson Maria , Schulz Anja , Fricker Martina , Christiansson Anders , Granum Per Einar , Märtlbauer Erwin , Nguyen-The Christophe , Salkinoja-Salonen Mirja , Scherer Siegfried
Published: January 2005

An in-depth polyphasic approach was applied to study the population structure of the human pathogen Bacillus cereus. To assess the intraspecific biodiversity of this species, which is the causative agent of gastrointestinal diseases, a total of 90 isolates from diverse geographical origin were studied by genetic [M13-PCR, random amplification of polymorphic DNA (RAPD), multilocus sequence typing (MLST)] and phenetic [Fourier transform Infrared (FTIR), protein profiling, biochemical assays] methods. The strain set included clinical strains, isolates from food remnants connected to outbreaks, as well as isolates from diverse food environments with a well documented strain history. The phenotypic and genotypic analysis of the compiled panel of strains illustrated a considerable diversity among B. cereus connected to diarrhoeal syndrome and other non-emetic food strains, but a very low diversity among emetic isolates. Using all typing methods, cluster analysis revealed a single, distinct cluster of emetic B. cereus strains. The isolates belonging to this cluster were neither able to degrade starch nor could they ferment salicin; they did not possess the genes encoding haemolysin BL (Hbl) and showed only weak or no haemolysis. In contrast, haemolytic-enterotoxin-producing B. cereus strains showed a high degree of heterogeneity and were scattered over different clusters when different typing methods were applied. These data provide evidence for a clonal population structure of cereulide-producing emetic B. cereus and indicate that emetic strains represent a highly clonal complex within a potentially panmictic or weakly clonal background population structure of the species. It may have originated only recently through acquisition of specific virulence factors such as the cereulide synthetase gene.
Molecular evolution of Vibrio pathogenicity island-2 (VPI-2): mosaic structure among Vibrio cholerae and Vibrio mimicus natural isolates
Authors: Jermyn William S. , Boyd E. Fidelma
Published: January 2005

Vibrio cholerae is a Gram-negative rod that inhabits the aquatic environment and is the aetiological agent of cholera, a disease that is endemic in much of Southern Asia. The 57·3 kb Vibrio pathogenicity island-2 (VPI-2) is confined predominantly to toxigenic V. cholerae O1 and O139 serogroup isolates and encodes 52 ORFs (VC1758 to VC1809), which include homologues of an integrase (VC1758), a restriction modification system, a sialic acid metabolism gene cluster (VC1773–VC1783), a neuraminidase (VC1784) and a gene cluster that shows homology to Mu phage. In this study, a 14·1 kb region of VPI-2 comprising ORFs VC1773 to VC1787 was identified by PCR and Southern blot analyses in all 17 Vibrio mimicus isolates examined. The VPI-2 region in V. mimicus was inserted adjacent to a serine tRNA similar to VPI-2 in V. cholerae. In 11 of the 17 V. mimicus isolates examined, an additional 5·3 kb region encoding VC1758 and VC1804 to VC1809 was present adjacent to VC1787. The evolutionary history of VPI-2 was reconstructed by comparative analysis of the nanH (VC1784) gene tree with the species gene tree, deduced from the housekeeping gene malate dehydrogenase (mdh), among V. cholerae and V. mimicus isolates. Both gene trees showed an overall congruence; on both gene trees V. cholerae O1 and O139 serogroup isolates clustered together, whereas non-O1/non-O139 serogroup isolates formed separate divergent branches with similar clustering of strains within the branches. One exception was noted: on the mdh gene tree, V. mimicus sequences formed a distinct divergent lineage from V. cholerae sequences; however, on the nanH gene tree, V. mimicus clustered with V. cholerae non-O1/non-O139 isolates, suggesting horizontal transfer of this region between these species.
Temperature adaptation in Dictyostelium: role of Δ5 fatty acid desaturase
Authors: Saito Tamao , Kato Atsushi , Ochiai Hiroshi , Morita Naoki
Published: January 2005

Membrane fluidity is critical for proper membrane function and is regulated in part by the proportion of unsaturated fatty acids present in membrane lipids. The proportion of these lipids in turn varies with temperature and may contribute to temperature adaptation in poikilothermic organisms. The fundamental question posed in this study was whether the unsaturation of fatty acids contributes to the ability to adapt to temperature stress inDictyostelium. First, fatty acid composition was analysed and it was observed that the relative proportions of dienoic acids changed with temperature. To investigate the role of dienoic fatty acids in temperature adaptation, null mutants were created in the two known Δ5 fatty acid desaturases (FadA and FadB) that are responsible for the production of dienoic fatty acids. ThefadBnull mutant showed no significant alteration in fatty acid composition or in phenotype. However, the disruption offadAresulted in a large drop in dienoic fatty acid content from 51·2 to 4·1 % and a possibly compensatory increase in monoenoic fatty acids (40·9–92·4 %). No difference was detected in temperature adaptation with that of wild-type cells during the growth phase. However, surprisingly, mutant cells developed more efficiently than the wild-type at elevated temperatures. These results show that the fatty acid composition ofDictyosteliumchanges with temperature and suggest that the regulation of dienoic fatty acid synthesis is involved in the development ofDictyosteliumat elevated temperatures, but not during the growth phase.
Structural and functional analysis of a 0.5-Mb chicken region orthologous to the imprinted mammalianAscl2/Mash2–Igf2–H19region
Authors: Yokomine Takaaki , Shirohzu Hisao , Purbowasito Wahyu , Toyoda Atsushi , Iwama Hisakazu , Ikeo Kazuho , Hori Tetsuya , Mizuno Shigeki , Tsudzuki Masaoki , Matsuda Yoh-ichi , Hattori Masahira , Sakaki Yoshiyuki , Sasaki Hiroyuki
Published: January 2005

Previous studies revealed thatIgf2andMpr/Igf2rare imprinted in eutherian mammals and marsupials but not in monotremes or birds.Igf2lies in a large imprinted cluster in eutherians, and its imprinting is regulated by long-range mechanisms. As a step to understand how the imprinted cluster evolved, we have determined a 490-kb chicken sequence containing the orthologs of mammalianAscl2/Mash2, Ins2andIgf2. We found that most of the genes in this region are conserved between chickens and mammals, maintaining the same transcriptional polarities and exon–intron structures. However,H19, an imprinted noncoding transcript, was absent from the chicken sequence. ChickenASCL2/CASH4andINS, the orthologs of the imprinted mammalian genes, showed biallelic expression, further supporting the notion that imprinting evolved after the divergence of mammals and birds. TheH19imprinting center and many of the local regulatory elements identified in mammals were not found in chickens. Also, a large segment of tandem repeats and retroelements identified between the two imprinted subdomains in mice was not found in chickens. Our findings show that the imprinted genes were clustered before the emergence of imprinting and that the elements associated with imprinting probably evolved after the divergence of mammals and birds.
Computational prediction of miRNAs in Arabidopsis thaliana
Authors: Adai Alex , Johnson Cameron , Mlotshwa Sizolwenkosi , Archer-Evans Sarah , Manocha Varun , Vance Vicki , Sundaresan Venkatesan
Published: January 2005

MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression in animals and plants. Comparative genomic computational methods have been developed to predict new miRNAs in worms, flies, and humans. Here, we present a novel single genome approach for the detection of miRNAs in Arabidopsis thaliana. This was initiated by producing a candidate miRNA-target data set using an algorithm called findMiRNA, which predicts potential miRNAs within candidate precursor sequences that have corresponding target sites within transcripts. From this data set, we used a characteristic divergence pattern of miRNA precursor families to select 13 potential new miRNAs for experimental verification, and found that corresponding small RNAs could be detected for at least eight of the candidate miRNAs. Expression of some of these miRNAs appears to be under developmental control. Our results are consistent with the idea that targets of miRNAs encompass a wide range of transcripts, including those for F-box factors, ubiquitin conjugases, Leucine-rich repeat proteins, and metabolic enzymes, and that regulation by miRNAs might be widespread in the genome. The entire set of annotated transcripts in the Arabidopsis genome has been run through findMiRNA to yield a data set that will enable identification of potential miRNAs directed against any target gene.
Comparison of the chicken and turkey genomes reveals a higher rate of nucleotide divergence on microchromosomes than macrochromosomes
Authors: Axelsson Erik , Webster Matthew T. , Smith Nick G.C. , Burt David W. , Ellegren Hans
Published: January 2005

A distinctive feature of the avian genome is the large heterogeneity in the size of chromosomes, which are usually classified into a small number of macrochromosomes and numerous microchromosomes. These chromosome classes show characteristic differences in a number of interrelated features that could potentially affect the rate of sequence evolution, such as GC content, gene density, and recombination rate. We studied the effects of these factors by analyzing patterns of nucleotide substitution in two sets of chicken-turkey sequence alignments. First, in a set of 67 orthologous introns, divergence was significantly higher in microchromosomes (chromosomes 11-38; 11.7% divergence) than in both macrochromosomes (chromosomes 1-5; 9.9% divergence; P = 0.016) and intermediate-sized chromosomes (chromosomes 6-10; 9.5% divergence; P = 0.026). At least part of this difference was due to the higher incidence of CpG sites on microchromosomes. Second, using 155 orthologous coding sequences we noted a similar pattern, in which synonymous substitution rates on microchromosomes (13.1%) were significantly higher than were rates on macrochromosomes (10.3%; P = 0.024). Broadly assuming neutrality of introns and synonymous sites, or constraints on such sequences do not differ between chromosomal classes, these observations imply that microchromosomal genes are exposed to more germ line mutations than those on other chromosomes. We also find that dN/dS ratios for genes located on microchromosomes (average, 0.094) are significantly lower than those of macrochromosomes (average, 0.185; P = 0.025), suggesting that the proteins of genes on microchromosomes are under greater evolutionary constraint.
Comparative genome sequencing ofDrosophila pseudoobscura: Chromosomal, gene, andcis-element evolution
Authors: Richards Stephen , Liu Yue , Bettencourt Brian R. , Hradecky Pavel , Letovsky Stan , Nielsen Rasmus , Thornton Kevin , Hubisz Melissa J. , Chen Rui , Meisel Richard P. , Couronne Olivier , Hua Sujun , Smith Mark A. , Zhang Peili , Liu Jing , Bussemaker Harmen J. , van Batenburg Marinus F. , Howells Sally L. , Scherer Steven E. , Sodergren Erica , Matthews Beverly B. , Crosby Madeline A. , Schroeder Andrew J. , Ortiz-Barrientos Daniel , Rives Catharine M. , Metzker Michael L. , Muzny Donna M. , Scott Graham , Steffen David , Wheeler David A. , Worley Kim C. , Havlak Paul , Durbin K. James , Egan Amy , Gill Rachel , Hume Jennifer , Morgan Margaret B. , Miner George , Hamilton Cerissa , Huang Yanmei , Waldron Lenée , Verduzco Daniel , Clerc-Blankenburg Kerstin P. , Dubchak Inna , Noor Mohamed A.F. , Anderson Wyatt , White Kevin P. , Clark Andrew G. , Schaeffer Stephen W. , Gelbart William , Weinstock George M. , Gibbs Richard A.
Published: January 2005

We have sequenced the genome of a secondDrosophilaspecies,Drosophila pseudoobscura, and compared this to the genome sequence ofDrosophila melanogaster, a primary model organism. Throughout evolution the vast majority ofDrosophilagenes have remained on the same chromosome arm, but within each arm gene order has been extensively reshuffled, leading to a minimum of 921 syntenic blocks shared between the species. A repetitive sequence is found in theD. pseudoobscuragenome at many junctions between adjacent syntenic blocks. Analysis of this novel repetitive element family suggests that recombination between offset elements may have given rise to many paracentric inversions, thereby contributing to the shuffling of gene order in theD. pseudoobscuralineage. Based on sequence similarity and synteny, 10,516 putative orthologs have been identified as a core gene set conserved over 25–55 million years (Myr) since thepseudoobscura/melanogasterdivergence. Genes expressed in the testes had higher amino acid sequence divergence than the genome-wide average, consistent with the rapid evolution of sex-specific proteins.Cis-regulatory sequences are more conserved than random and nearby sequences between the species—but the difference is slight, suggesting that the evolution ofcis-regulatory elements is flexible. Overall, a pattern of repeat-mediated chromosomal rearrangement, and high coadaptation of both male genes andcis-regulatory sequences emerges as important themes of genome divergence between these species ofDrosophila.
Comparison of splice sites in mammals and chicken
Authors: Abril Josep F. , Castelo Robert , Guigó Roderic
Published: January 2005

We have carried out an initial analysis of the dynamics of the recent evolution of the splice-sites sequences on a large collection of human, rodent (mouse and rat), and chicken introns. Our results indicate that the sequences of splice sites are largely homogeneous within tetrapoda. We have also found that orthologous splice signals between human and rodents and within rodents are more conserved than unrelated splice sites, but the additional conservation can be explained mostly by background intron conservation. In contrast, additional conservation over background is detectable in orthologous mammalian and chicken splice sites. Our results also indicate that the U2 and U12 intron classes seem to have evolved independently since the split of mammals and birds; we have not been able to find a convincing case of interconversion between these two classes in our collections of orthologous introns. Similarly, we have not found a single case of switching between AT-AC and GT-AG subtypes within U12 introns, suggesting that this event has been a rare occurrence in recent evolutionary times. Switching between GT-AG and the noncanonical GC-AG U2 subtypes, on the contrary, does not appear to be unusual; in particular, T to C mutations appear to be relatively well tolerated in GT-AG introns with very strong donor sites.
Expression of the β chemokines CCL3, CCL4, CCL5 and their receptors in idiopathic inflammatory myopathies
Authors: Civatte M. , Bartoli C. , Schleinitz N. , Chetaille B. , Pellissier J. F. , Figarella‐Branger D.
Published: January 2005

The idiopathic inflammatory myopathies (IIM) are a group of autoimmune diseases characterized by chronic lymphocytic and macrophagic infiltration in muscle. Because the mechanism for recruitment of these cells probably involves chemokines, we focused on the study of the expression pattern of some β chemokines and receptors because it may provide a basis for selective immunotherapy. The expression of CCL3 (MIP‐1α), CCL4 (MIP‐1β), CCL5 (RANTES) and their main receptors (CCR1 and CCR5) was studied by semi‐quantitative reverse transcriptase polymerase chain reaction (RT‐PCR) and immunohistochemistry in a series of 16 IIM and five controls (four normal muscles and one tonsil). Except for CCL5, strong expression was observed by RT‐PCR with all molecules in all IIM subtypes in comparison to control muscle. Immunohistochemistry revealed diffuse CCL4 expression in all vessels in dermatomyositis. In both polymyositis and sporadic inclusion body myositis (s‐IBM) it was restricted to vessels in the vicinity of inflammatory exudates. CCL5 expression was low, restricted to a few inflammatory cells in all IIM; CCR1 expression was mainly restricted to macrophages and s‐IBM endothelial cells, whereas CCR5 was localized in inflammatory cells invading non‐necrotic muscle fibres. Expressions of both receptors were also recorded in few muscle fibres. In conclusion, the upregulation of β chemokines and receptors in IIM and their differential expression by various cells may contribute to chronic inflammation and to the peculiar distribution of inflammatory exudates in these diseases.
Fatal familial insomnia with an unusual prion protein deposition pattern: an autopsy report with an experimental transmission study
Authors: Sasaki K. , Doh‐ura K. , Wakisaka Y. , Tomoda H. , Iwaki T.
Published: January 2005

We recently performed a post‐mortem examination on a Japanese patient who had a prion protein gene mutation responsible for fatal familial insomnia (FFI). The patient initially developed cerebellar ataxia, but finally demonstrated insomnia, hyperkinetic delirium, autonomic signs and myoclonus in the late stage of the illness. Histological examination revealed marked neuronal loss in the thalamus and inferior olivary nucleus; however, prion protein (PrP) deposition was not proved in these lesions by immunohistochemistry. Instead, PrP deposition and spongiform change were both conspicuous within the cerebral cortex, whereas particular PrP deposition was also observed within the cerebellar cortex. The abnormal protease‐resistant PrP (PrPres) molecules in the cerebral cortex of this case revealed PrPres type 2 pattern and were compatible with those of FFI cases, but the transmission study demonstrated that a pathogen in this case was different from that in a case with classical FFI. By inoculation with homogenate made from the cerebral cortex, the disease was transmitted to mice, and neuropathological features that were distinguishable from those previously reported were noted. These findings indicate the possibility that a discrete pathogen was involved in the disease in this case. We suggest that not only the genotype of the PrP gene and some other as yet unknown genetic factors, but also the variation in pathogen strains might be responsible for the varying clinical and pathological features of this disease.
Histomorphometry of tumour cell nuclei in astrocytomas using shape analysis, densitometry and topometric analysis
Authors: Nafe R. , Schlote W. , Schneider B.
Published: January 2005

Although tumour cell nuclei are important histological structures for grading of astrocytomas according to the WHO‐classification of brain tumours, there is no reported morphometric study of astrocytomas which describes quantitatively the four main morphologic criteria of tumour cell nuclei: size, shape, texture (densitometric characteristics) and spatial relationships between the nuclei (topometric analysis). Using a set of morphometric parameters describing these criteria as well as the Ki67‐proliferation index, 74 astrocytomas from 74 patients were studied by means of a digital image analysis system. The objective of the study was to test, if these morphometric parameters were sufficient for statistical discrimination between pilocytic astrocytomas WHO‐grade I, astrocytomas grade II and anaplastic astrocytomas grade III. Our results showed a correct reclassification of 97.3% (72/74) of  the  cases  with  respect  to  the  tumour  grade  by  means of cross‐validated discriminant analysis. Morphometric parameters characterizing nuclear shape (shape factors, Fourier‐amplitudes) showed the most prominent differences between the three groups of cases, followed by topometric parameters (number of neighbours per nucleus, distances between the nuclei). Less pronounced differences between the tumour grades were found for parameters characterizing nuclear size, nuclear texture and the Ki67‐proliferation index. In conclusion, the present morphometric procedure provided good discrimination between the tumour grades, supporting the view that histomorphometry of tumour cell nuclei could be a valuable tool for grading of astrocytomas.
Accumulation of NEDD8 in neuronal and glial inclusions of neurodegenerative disorders
Authors: Mori F. , Nishie M. , Piao Y.‐S. , Kito K. , Kamitani T. , Takahashi H. , Wakabayashi K.
Published: January 2005

NEDD8 (neural precursor cell expressed, developmentally down‐regulated 8) is a ubiquitin‐like protein that controls vital biological events through its conjugation to members of the cullin family, which are components of certain ubiquitin E3  ligases.  Recent  studies  have  shown  that  NEDD8 is incorporated into Lewy bodies (LBs) in Parkinson's disease, Mallory bodies in alcoholic liver disease and Rosenthal fibres in astrocytoma. In order to examine whether NEDD8 plays a role in the formation of ubiquitinated inclusions, we performed immunohistochemical staining of brain tissue from patients with various neurodegenerative disorders, using an affinity‐purified polyclonal antibody raised against NEDD8 that did not cross‐react with ubiquitin. In LB disease, NEDD8 immunoreactivity was present in almost all of the LBs and Lewy neurites. Moreover, NEDD8 immunoreactivity was found in a variety of ubiquitinated inclusions, including neuronal and oligodendroglial inclusions in multiple system atrophy, neurofibrillary tangles in Alzheimer's disease, ubiquitinated inclusions in motor neurone disease, and intranuclear inclusions in triplet repeat diseases. These findings suggest that NEDD8 is involved in the formation of various ubiquitinated inclusions via the ubiquitin‐proteasome system.
The case for a central nervous system (CNS) origin for the Schwann cells that remyelinate CNS axons following concurrent loss of oligodendrocytes and astrocytes
Authors: Blakemore W. F.
Published: January 2005

In certain experimental and naturally occurring pathological situations in the central nervous system (CNS), demyelinated axons are remyelinated by Schwann cells. It has always been assumed that these Schwann cells are derived from Schwann cells associated with peripheral nerves. However, it has become apparent that CNS precursors can give rise to Schwann cells in vitro and following transplantation into astrocyte‐free areas of demyelination in vivo. This paper compares the behaviour of remyelinating Schwann cells following transplantation of peripheral nerve derived Schwann cells over, and into, astrocyte‐depleted areas of demyelination to that which follows transplantation of CNS cells and that seen in normally remyelinating ethidium bromide induced demyelinating lesions. It concludes that while the examination of normally remyelinating lesions can not resolve the origin of the remyelinating Schwann cells, the results from transplantation studies provide strong evidence that the Schwann cells that remyelinate CNS axons are most likely generated from CNS precursors. In addition these studies also indicate that the precursors that give rise to these Schwann cells are the same cells that give rise to remyelinating oligodendrocytes.
Networking and innovation: a systematic review of the evidence
Authors: Pittaway Luke , Robertson Maxine , Munir Kamal , Denyer David , Neely Andy
Published: January 2005

Recent work on competitiveness has emphasized the importance of business networking for innovativeness. Until recently, insights into the dynamics of this relationship have been fragmented. This paper presents a systematic review of research linking the networking behaviour of firms with their innovative capacity. We find that the principal benefits of networking as identified in the literature include: risk sharing; obtaining access to new markets and technologies; speeding products to market; pooling complementary skills; safeguarding property rights when complete or contingent contracts are not possible; and acting as a key vehicle for obtaining access to external knowledge. The evidence also illustrates that those firms which do not co‐operate and which do not formally or informally exchange knowledge limit their knowledge base long term and ultimately reduce their ability to enter into exchange relationships. At an institutional level, national systems of innovation play an important role in the diffusion of innovations in terms of the way in which they shape networking activity. The paper provides evidence suggesting that network relationships with suppliers, customers and intermediaries such as professional and trade associations are important factors affecting innovation performance and productivity. Where networks fail, it is due to inter‐firm conflict, displacement, lack of scale, external disruption and lack of infrastructure. The review identifies several gaps in the literature that need to be filled. For instance, there is a need for further exploration of the relationship between networking and different forms of innovation, such as process and organisational innovation. Similarly, we need better understanding of network dynamics and network configurations, as well as the role of third parties such as professional and trade associations. Our study highlights the need for interdisciplinary research in these areas.
Adoption of promising practices: a systematic review of the evidence
Authors: Leseure Michel J. , Bauer Joachim , Birdi Kamal , Neely Andy , Denyer David
Published: January 2005

This paper presents the results of a systematic literature review about the adoption of promising practices by organizations. The objective of the study was to gather empirical evidence to explain why the UK rate of promising practices adoption is poor compared with that of its competitors. The paper illustrates how a vastly dispersed collection of empirical data results can be integrated through a rigorous review process. The conclusion is that, although there is evidence to suggest that an adoption gap exists, the root causes of this gap cannot at present be diagnosed from the available evidence. Directions for future research are discussed.
Team Autonomy, Performance, and Member Job Strain: Uncovering the Teamwork KSA Link
Authors: Leach Desmond J. , Wall Toby D. , Rogelberg Steven G. , Jackson Paul R.
Published: January 2005

En raison du développement des équipes de travail dans les organisations, on souhaite obtenir des informations sur la meilleure façon de structurer les groupes pour les rendre efficients. Cette étude porte sur la relation de l’expérience de l’autonomie et du travail en équipe, des capacités et des compétences (KSAs) avec la performance du groupe et l’effort émanant de ses membres. Deux modèles ont été mis à l’épreuve à partir d’une recherche théorique et empirique continue. Des données provenant d’un échantillon de 41 équipes de production (174 participants) apportèrent des éléments en faveur du modèle de médiation selon lequel l’autonomie est associée à la perfomance et à l’effort par l’intermédiaire des KSAs. Le modèle alternatif de modération qui suppose que l’autonomie et les KSAs interagissent pour déboucher sur la performance et l’effort ne fut pas corroboré.

Given the increasing use of work teams in organizations, interest exists in identifying the best ways to design teams so that they lead to positive outcomes. This study examined how team autonomy and teamwork knowledge, skills, and abilities (KSAs) relate to team performance and member job strain. Based on extant empirical and theoretical work, two models were tested. findings from a sample of 41 production teams (174 team members) showed support for the mediation model—that autonomy is associated with performance and strain through teamwork KSAs. The alternative moderation model, suggesting that autonomy and teamwork KSAs interact in predicting performance and strain, was not supported.
Linking Situational Constraints to Customer Satisfaction in a Service Environment
Authors: Martínez‐Tur Vicente , Peiró José M. , Ramos José
Published: January 2005

Cet article examine les rapports entre la satisfaction de la clientèle et les contraintes relevant des situations techniques et sociales. A cette fin, une enquête de terrain fut réalisée auprès d’un échantillon de 57 managers et 835 clients d’organisations de service. On a recensé les contraintes sociales et techniques vécues par les managers. La satisfaction des clients a également été mesurée avec plusieurs aspects des services. En général, l’absence de situation contraignante dans les organisations de service était en relation positive avec la satisfaction de la clientèle. Les résultats montrent aussi que la seule contribution des contraintes techniques à la satisfaction des clients était supérieure à celle des contraintes sociales. Nous signalons des implications managériales et des orientations pour les futures recherches portant sur les relations entre les contraintes et la satisfaction des clients.

This paper aims to test the links of social and technical situational constraints to customer satisfaction with services. To this end, a field survey study was conducted using a sample of 57 managers and 835 customers of service organisations. We studied social and technical constraints perceived by managers. Customer satisfaction with several service attributes was also measured. In general, a lack of situational constraints in service organisations was positively associated with customer satisfaction. The results also showed that the unique contribution of technical constraints to customer satisfaction was greater than that of social constraints. We point out managerial implications and future directions for research on constraints–customer satisfaction relationships.
Workaholism in the Netherlands: Measurement and Implications for Job Strain and Work–Nonwork Conflict
Authors: Taris Toon W. , Schaufeli Wilmar B. , Verhoeven Lotus C.
Published: January 2005

Cette recherche traite de la mesure et des conséquences du travail comme conduite addictive aux Pays‐Bas. La première étude décrit le développement et la validation d’une version hollandaise de la Work Addiction Risk Scale (WART) de Robinson (1999). Une analyse factorielle portant sur les réponses de 356 sujets a montré que la structure factorielle de la WART hollandaise était analogue à celle de la version américaine. La deuxième étude (N= 232) avait pour objectif de décider si la sous‐échelle ≪tendances compulsives≫ (CT) de la WART pouvait être utilisée comme mesure abrégrée du travail addictif. Le recouvrement entre l’échelle complète de 25 items et la sous‐échelle CT était large et la répartition des corrélations avec les autres concepts très proche. La troisième étude (N= 199) mit à l’épreuve un modèle des effets du travail addictif (CT) sur l’épusiement et le conflit travail—hors‐travail, montrant que le travail addictif affectait ces deux variables dépendantes à la fois directement et indirectement (par l’intermédiaire des exigences perçues du travail). On conclut 1) que la version hollandaise de la WART est très proche de la version américaine d’origin; 2) que la WART et la sous‐échelle CT sont toutes deux des mesures valides du travail addictif; 3) que le travail addictif est un concept virtuellement majeur pour l’étude du travail et du stress.

This research deals with the measurement and consequences of workaholism in the Netherlands. Study 1 describes the development and validation of a Dutch version of Robinson's (1999) Work Addiction Risk Scale (WART). Confirmatory factor analysis (total N= 356) revealed that the factorial structure of the Dutch WART was similar to that of the US original. Study 2 (N= 232) examined whether the Compulsive Tendencies (CT) subscale of the WART could be used as a short measure of workaholism. The overlap between the full 25‐item WART and the CT subscale was high, whereas the patterns of correlations with other concepts were very similar. Study 3 (N= 199) tested a process model for the effects of workaholism (i.e., CT) on exhaustion and work–nonwork conflict, showing that workaholism affected these two outcome variables both directly and indirectly (via perceived job demands). It is concluded that: (i) the Dutch version of the WART is very similar to the US original; (ii) the WART and the CT subscale are both valid measures of workaholism; and (iii) workaholism is a potentially important concept in the study of work and stress.
An Integrated Model for the Study of Teacher Motivation
Authors: Neves de Jesus Saul , Lens Willy
Published: January 2005

Des recherches récentes ont montré que les enseignants souffraient plus que d’autres groupes professionnels d’un manque de motivation au travail. Une compréhension globale de la motivation des enseignants exige un modèle adéquat. L’objectif principal de cette recherche était de proposer et de mettre à l’épreuve un modèle de la motivation des enseignants qui intégre des concepts de plusieurs théories cognitivo‐motivationelles. Le modèle intégré s’appuie sur la schéma expectation‐valence et celui de l’incapacité acquise, mais surmonte quelques‐unes de leurs imperfections. L’échantillon était composé de 272 enseignants des écoles élémentaires et secondaires du Portugal. Ils ont répondu à une série d’inventaires destinés à mesurer leurs expectations de contrôle, de succès et d’efficacité, leurs attributions, leur motivation intrinsèque, la valence de leurs buts perçus et comment tout ceci interagit pout agir sur l’engagement professionnel (la variable exogène du modèle). Les analyses des coefficients de pistes et de la variance des variables endogènes valident le modèle intégré proposé ici et suggèrent des stratégies de formation pour accroître la motivation des enseignants.

Recent studies show that teachers suffer more than other professional groups from the occupational lack of motivation. A global understanding of teacher motivation requires an adequate framework for its study. The main goal of the current research was to propose and test a model of teacher motivation that integrates constructs from several cognitive‐motivational theories. This integrative model starts from the perspectives of Expectancy‐Value and Learned Helplessness but overcomes some of the limitations of each. The participants were 272 elementary and secondary teachers in Portugal. They responded to a series of inventories designed to measure their expectancies of control, success and efficacy, attributions, intrinsic motivation and perceived goal value levels, and how these interact to influence professional engagement (the model's exogenous variable). Analyses of path coefficients and the variance of endogenous variables support the proposed integrated model and suggest strategies for teacher education that may increase teacher motivation.
The Game Academics Play: Editors versus Authors
Authors: Faria João Ricardo
Published: January 2005

This article studies a game between authors and editors. Editors play as leaders while authors are the followers. Authors maximize the number of publications seeking to increase the impact of their work in the literature, captured by citations. Editors maximize the quality of papers they publish in order to increase the reputation of their journals. The main results are: (i) rules aimed at increasing scholars productivity, such as requirements to obtain tenure, increase author's citations and journal's quality; (ii) editors willingness to build journal's reputation hurt journal's quality and increase author's publications; (iii) journal's reputation increases citations and journal's quality.
Testing Multiple Non‐Nested Factor Demand Systems
Authors: Manera Matteo , McAleer Michael
Published: January 2005

This article explains how to obtain straightforward extensions of the most popular univariate non‐nested statistics, and of the RESET‐test, to a multivariate context and examines how to use these tests to compare alternative factor demand systems. The empirical application involves the classical Berndt–Khaled KLEM data set. A statistically adequate specification is determined for each competing factor demand system. The empirical results are interpreted for each system, the models are compared on the basis of multivariate paired and joint non‐nested procedures and practical indications about what to expect if these tests are applied to alternative factor demand specifications are provided.
Managing Complex Vehicle System Simulation Models for Automotive System Development
Authors: Jennings Mark , Rangan Ravi
Published: January 2005

A Model Management System (MMS) for vehicle dynamic system modeling is described, including lessons learned from a pilot implementation at Ford Motor Company. For complex vehicle systems, early phases of product development (requirements analysis and high-level conceptual design) drive innovation, cost, quality, and timing. These phases have received little attention relative to product lifecycle management. Selected system model architectures are reviewed with elements of model configuration and application to hybrid electric vehicle development. The examples establish MMS requirements, leading to a reference information model promoting collaboration, reuse, and process autonomy.
Design and Implementation of a Distributed Information System for Collaborative Product Development
Authors: Wu Teresa , Xie Nan , Blackhurst Jennifer
Published: January 2005

Collaborative Product Development (CPD) is an engineering process that involves decision-making through iterative communication and coordination among product designers throughout the lifecycle of the product. The high level of collaboration and communication of a CPD environment requires a robust Distributed Information System. In this paper, we review existing research related to CPD and propose an information framework termed VE4PD based on the integration of web services and agent technologies to manage the CPD process. An implementation system is developed to validate the application.
STEP, XML, and UML: Complementary Technologies1
Authors: Peak Russell S. , Lubell Joshua , Srinivasan Vijay , Waterbury Stephen C.
Published: January 2005

One important aspect of product lifecycle management (PLM) is the computer-sensible representation of product information. Over the past 15 years or so, several languages and technologies have emerged that vary in their emphasis and applicability for such usage. ISO 10303, informally known as the Standard for the Exchange of Product Model Data (STEP), contains the high-quality product information models needed for electronic business solutions. By using STEP, the aerospace, automotive, and shipbuilding industries are saving $150M/yr primarily in areas related to geometric modeling. However, traditional STEP-based model information is represented using languages that are unfamiliar to most application developers, thus impeding widespread usage in other areas. This paper discusses efforts underway to make STEP information models available via mechanisms familiar to more business application developers, specifically XML and the Unified Modeling Language™ (UML®). We also present a vision and roadmap for STEP integration with XML, UML, and other technologies to enable enhanced PLM interoperability. Our conclusion is that STEP, XML, and UML are complementary technologies, where STEP provides significant standardized content models, while XML and UML provide enhanced implementation methods. Together, they are a powerful force to enable pervasive digital representation and sharing of diverse technical information.
Information Integration Framework For Product Life-Cycle Management of Diverse Data
Authors: Morris Huong , Lee Simon , Shan Eric , Zeng Sai
Published: January 2005

Automobile, aerospace, and other industrial manufacturers have evolved over the years to use a multitude of computer-aided design (CAD) and product data management (PDM) systems and have long depended on single-vendor solutions to support their enterprise-wide engineering activities. Increased product complexity, distributed authoring environments, and the need for tighter team integration with partners and suppliers have created challenges and new opportunities for information technology (IT) vendors to be able to integrate systems from multiple independent software vendors (ISVs) to form a coherent Enterprise PDM system. This paper will describe, in detail, a case study and solution of an IBM Research project called Hedwig. Hedwig investigates creating robust solutions for Product Life-Cycle Management (PLM). We focus on several research issues, including information federation, data mapping, synchronization, and web services connections. We describe a working system that allows access to several heterogeneous PDM systems that are used in the automotive and aerospace industries.
An Intelligent Mediator-Based Framework for Enterprise Application Integration
Authors: Madhusudan Therani
Published: January 2005

Enterprise Application Integration (EAI) is a major problem confronting manufacturing organizations that have deployed large-scale enterprise information systems and aim to coordinate inter- and intraorganizational product development, supply-chain, and customer management activities. Successful EAI is a key enabling step toward implementation of viable Product Life-cycle Management (PLM) strategies. Extant EAI technologies, such as distributed object and messaging technologies for communication and ontology-based database schema integration, are tedious to develop and maintain in an organization. Though workflow management systems have enabled process coordination of both manual and system-oriented tasks in organizations, coping with the lack of adaptability and inter-operability in workflow systems is a manual and resource intensive effort. Recent advances in (i) standardized, modular, and distributed software delivery frameworks, such as web services; (ii) standard semantic markup languages for developing domain ontologies; and (iii) intelligent process coordination frameworks promise the development of flexible, responsive, integrated, and organic process management architectures. In this paper, we present an intelligent mediator-based architecture for enabling EAI. Intraorganizational information sources and services are made available via a web-services framework. An Integrated Service Planning and Execution (ISP&E) framework interleaves service composition and execution at the mediator to fulfill service requests. Processes that interleave information gathering and transactional tasks are generated using domain-independent Hierarchical Task Network (HTN) AI planning and a domain-specific ontology and then executed in a scalable and reliable manner. Benefits and limitations of mediator-based frameworks for EAI and topics for further research are discussed based on a prototype development experience.
Selective COX-2 Inhibitors and Renal Injury in Salt-Sensitive Hypertension
Authors: Hermann Matthias , Shaw Sidney , Kiss Eva , Camici Giovanni , Bühler Nico , Chenevard Remy , Lüscher Thomas F. , Gröne Hermann J. , Ruschitzka Frank
Published: January 2005

In view of the ongoing controversy of cardiorenal safety of selective COX-2 inhibitors (coxibs), the present study was designed to examine the effects of 2 different coxibs, celecoxib and rofecoxib, compared with a traditional NSAID, diclofenac, and placebo on renal morphology and function in salt-sensitive hypertension. Salt-sensitive (DS) and salt-resistant (DR) Dahl rats were fed with NaCl-enriched diet (4% NaCl) for 8 weeks. Diclofenac (DS-diclofenac), rofecoxib (DS-rofecoxib), celecoxib (DS-celecoxib), or placebo was added to chow from weeks 6 to 8. Immunostaining for monocytes/macrophages (ED1) and cytotoxic T lymphocytes (CD8) was performed. In addition, renal morphology and proteinuria were assessed. Renal cortex mRNA was isolated for determination of COX-2, eNOS, and CRP mRNA by real-time reverse-transcriptase polymerase chain reaction. Untreated hypertensive animals showed glomerular injury including collapsing glomerulopathy, mesangial sclerosis, mesangiolysis, extracapillary proliferation, protein drops, and an especially high grade of glomerulosclerosis (
P
<0.05 versus DR-placebo) and CD8-positive and ED1-positive cells (
P
<0.01 versus DR-placebo), which was improved by celecoxib but not by diclofenac and rofecoxib. C-reactive protein mRNA in renal cortex was increased in DS-placebo animals (
P
<0.05 versus DR-placebo) and normalized by celecoxib (
P
<0.05 versus DS-placebo), whereas eNOS mRNA was decreased in the DS-rofecoxib group (
P
<0.05 versus DR-placebo, DS-celecoxib, and DS-diclofenac). Proteinuria was observed in hypertensive animals (
P
<0.0001 versus DR-placebo), increased by rofecoxib (
P
<0.05 versus DS-placebo), and normalized by celecoxib (
P
=0.0015 versus DS-placebo). This head-to-head comparison of selective and nonselective COX inhibitors demonstrates differential effects of coxibs on renal morphology and function in salt-dependent hypertension.
Angiotensin II and the Endothelium
Authors: Watanabe Tetsu , Barker Thomas A. , Berk Bradford C.
Published: January 2005

The initial view of the renin-angiotensin system focused on the role of angiotensin II as a hormone involved in blood pressure control, based on its role in renal salt and water regulation, as well as central nervous system (thirst) and vascular smooth muscle tone. Subsequent data showed a role for angiotensin II in long-term effects on cardiovascular structure, including cardiac hypertrophy and vascular remodeling. Importantly, recent human studies with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers have demonstrated exciting clinical benefits including decreases in incidence of stroke, diabetes, and end-stage renal disease that suggest important new mechanisms of action. In this review, we focus on new roles for the renin-angiotensin system in the endothelium based on the concepts of diverse signals and effects mediated by multiple angiotensin I- and angiotensin II-derived peptides, multiple angiotensin metabolizing enzymes, multiple receptors, and vascular bed-specific intracellular signals.
The Parrot Effect
Authors: van Baaren Rick B.
Published: January 2005

A study of tipping behavior in the Netherlands found that mimicry improved tips. When waitresses repeated customers' orders verbatim, they received larger tips than when they merely acknowledged or paraphrased the orders. Since restaurants in the Netherlands add service charges to patrons' checks, the size of any tip that customers leave can be taken as a reasonably firm indication of the extent to which customers were pleased with the service. The servers in the study made sure that customers knew the order had been received regardless of whether they repeated back the order, in one instance by writing the order in the customers’ presence. Mimicry still brought larger tips than did either an oral paraphrase or written acknowledgment. The findings lend credence to the concept that people feel more comfortable with those who behave as they do and showthat people do not generally take conscious notice that they are being mimicked.