bluuebunny/crossref_metadata_2025 huggingface dataset:
An application of Gumbel's bivariate exponential distribution in estimation of warranty cost of motor cycles
Authors: Pal Surajit , Murthy G.S.R.
Published: April 2003

In this article we present an application of Gumbel's bivariate exponential distribution model in the context of estimating warranty costs of motor cycles under a new warranty policy. The problem in question is as follows: Under the present two‐dimensional warranty policy, repair costs (termed as warranty costs) of a motorcycle during the age of first six months or within the usage of 8,000 kilometers are borne by the company. To enhance customer satisfaction, the company wanted to bear the repair costs up to an age of one year or a usage of 12,000 kilometers. The problem is to estimate the expected hike in warranty costs if the warranty policy were revised as mentioned above. Using the past data, the problem is solved by studying the underlying renewal process. Gumbel's bivariate exponential distribution function is found to be useful in approximating the renewal function. Some practical difficulties posed by the past data in the analysis are highlighted and tackled in an interesting way.
Customer‐relationship levels – from spurious to true relationships
Authors: Liljander Veronica , Roos Inger
Published: April 2003

Relationship marketing (RM) has been widely accepted as an important determinant of long‐term business success and is believed to be especially well suited for services because of the personal contact between customers and service providers. Past research has focused mainly on the advantages of RM for companies, while less attention has been paid to relationships from the customer’s point of view. We suggest that relationships may be described as ranging from spurious to true, depending on customer‐perceived relationship benefits, trust and commitment. A qualitative study of customer relationships was conducted in a car dealership, where profitability depends on customer commitment to both after‐sales services and the car brand. Customer relationships were found to be more spurious than true. The study revealed that behavioural commitment to after‐sales services was high, but that affective commitment was low to moderate. Customers were satisfied but did not perceive the services to be superior to the competitors’ service offerings. They trusted authorised repair in general and did not feel that after‐sales service would have more than a minor influence on their future car purchases.
Trust in industrial service relationships: behavioral consequences, antecedents and the moderating effect of the duration of the relationship
Authors: Gounaris Spiros P. , Venetis Karin
Published: April 2003

Building on previous studies which suggested that trust is a critical factor in facilitating exchange relationships, the authors investigate with empirically derived data the role of service quality and customer bonding as antecedents of trust in relatively newer vis‐à‐vis a relatively mature relationship between the provider of business‐to‐business services and the client. The findings presented here show that the time element is critical to the effect that both service quality and successful customer bonding bear in trust development. Furthermore, the results of the study suggest that not all dimensions of the quality of the service offered by the provider contribute equally in the provider’s trustworthiness. Similarly, specific customer bonding techniques foster the extent to which the client trusts the service provider while others do not have an impact on the trustworthiness of the provider.
Curing and caring in surgical services: a relationship approach
Authors: Orava Markus , Tuominen Pekka
Published: April 2003

The purpose of this study is to describe and analyse the quality of a professional surgical service process, and to reveal the main elements that constitute excellence in the experience of the surgical service of a private hospital. First, a theoretical framework for the surgical service process is created. Second, empirical research is conducted through a mail survey of surgical patients in a private hospital. A total of 240 questionnaires were delivered and the response rate was 83 per cent. Third, the underlying quality dimensions in the surgical service process are constructed using factor analysis. Finally, the main elements of excellence in a surgical service experience are revealed by utilising discriminant analysis. Empirical results indicate that, in private surgical services, the surgical procedure itself is the single most important element, but that it must be supplemented by quality dimensions in both output and process throughout the whole surgical service process.
ERP implementation: lessons from a case study
Authors: Al‐Mashari Majed , Al‐Mudimigh Abdullah
Published: April 2003

Many organizations have moved from stand‐alone business information systems applications to integrated enterprise‐wide systems, enterprise resource planning (ERP). The implementation of ERP packages has created an opportunity to re‐engineer business processes within and beyond the organizational scope. Most notably, SAP R/3 has been widely implemented to create value‐oriented business processes that enable a high level of integration, improve communication within internal and external business networks, and enhance the decision‐making process. Though many organizations have reported dramatic improvements from SAP R/3 implementation, others have experienced difficulties in getting the R/3 modules aligned with other business components and systems. This paper describes a case study of a failed implementation of SAP R/3 to re‐engineer the business processes of a major manufacturer. Lessons in terms of factors that led to failure and their future implications are discussed in the light of the contrasting experiences of several best practice companies.
E‐commerce and Arab intra‐trade
Authors: Pons Alexander , Aljifri Hassan , Fourati Khalid
Published: April 2003

This paper focuses on the disparity that exists between Arab and non‐Arab trading blocs and the potential that e‐commerce offers in narrowing this gap. The current Arab intra‐trade state of affairs is analyzed, targeting potential trade opportunities. These prospects are evaluated, along with the adoption of technology to render advantages to the Arab world. Many countries have and continue to benefit from the acceptance of e‐commerce; understanding its applicability and effectiveness beyond and within the Arab trading blocs is of vital importance to increase trade. Our analysis presents a perspective on regional trade and utilization of technology within the global community and broadening trade possibilities among Arab countries.
An evaluation of the characteristics of membrane materials suitable for the batch fabrication of dissolved oxygen sensors
Authors: Glasspool W.V. , Atkinson J.K.
Published: April 2003

The bulk batch fabrication process of thick film technology has been utilised in the design and production of miniature amperometric dissolved oxygen sensors based on potentiostatic and voltammetric operation. Three different polymers have been investigated as membrane materials – cellulose acetate, PTFE and PVC. PTFE has been deposited on the devices by aerosol spray and PVC and cellulose acetate by screen‐printing. These methods have been shown to be effective membrane fabrication techniques, and have significant implications in the field of chemical sensors as a whole. All the membrane covered devices investigated were found to exhibit sensitive and linear responses to dissolved oxygen. The effects of temperature and flow rate on sensor response have been investigated and the use of PVC and PTFE in place of cellulose acetate have been shown to reduce both effects. These membranes have also been shown to reduce the detrimental effects of fouling observed on the surfaces of cellulose acetate covered devices as they are powered in tap water.
The e‐flow audit: an evaluation of knowledge flow within and outside a high‐tech firm
Authors: Bontis Nick , Fearon Michael , Hishon Marissa
Published: April 2003

Use of computer mediated communication, specifically electronic mail (e‐mail), has grown exponentially in recent years reaching as high as 75 percent penetration per household in some countries. The penetration rate is even higher for corporate environments. E‐mail is the communication medium of choice for most businesses and can therefore be construed as a proxy for codified knowledge flow in organizations. This paper advances the knowledge management body of literature by empirically examining several phenomena. Specifically, a comparison is made between inter‐ and intra‐departmental knowledge flows in organizations. Furthermore, knowledge flows within functional departments as well as knowledge flows to and from the external environment are examined. Data were collected from 15,500 e‐mails logged over five random days in a high‐tech organization of 480 employees. These data were then mapped on to the organizational chart and compared with the perceptual responses of a survey administration. Quantitative results were then triangulated with qualitative data gathered during focus groups. The research results yielded two important findings: (1) individuals showed an interesting bias towards over‐estimating their perceived knowledge flow throughout the organization; and (2) the e‐flow audit is an insightful managerial tool which provides a snapshot for knowledge management evaluation.
Musings on integrated management systems
Authors: Karapetrovic Stanislav
Published: April 2003

Because of the avalanche of management system standards for business functions ranging from quality and environment to corporate social responsibility, integration of management systems that these standards describe has become a popular topic of research and practice. This paper provides a summary of the most important issues regarding integrated management systems (IMS), including the main problem, the reasons behind it, the differing routes toward a solution, and the meaning of the solution itself. The overwhelming need for a solution points in the direction of a methodology for the integration of internal management systems, not an integrated standard. This paper illustrates one such methodology, and applies it to provide a foundation for and guide the construction of an IMS. Finally, it is argued that the future of IMS rests with the extension of its minimalistic requirements towards a set of comprehensive criteria able to steer the delivery of excellence to all stakeholders.
Structure and structural dimensions for knowledge‐based organizations
Authors: Wang Catherine L. , Ahmed Pervaiz K.
Published: April 2003

Organizational forms have evolved over the decades. Organizational design reflects the systems view, which considers that structure consists of both hard and soft components, and is the superior composition of relationship between organizational elements. Structural dimensions are traditionally examined along three dimensions of formal relationship: hierarchical, functional, and the dimension of inclusion and centrality, underlining two prime types of structure: mechanistic and organic organizations. However, the knowledge economy makes new demands on organizational structuring based on processes. Informal structure better depicts actual organizational activities and reflects dynamic interaction that is critical to knowledge creation. This conceptual paper incorporates informal structure as an important dimension and further elaborates organizational structuring at a higher level: trust‐based relationship, externally‐oriented interactive relationship, and emotionally‐inclusive relationship; and their importance in the attainment of organizational success in the knowledge economy.
Adhesive Surface Proteins ofErysipelothrix rhusiopathiaeBind to Polystyrene, Fibronectin, and Type I and IV Collagens
Authors: Shimoji Yoshihiro , Ogawa Yohsuke , Osaki Makoto , Kabeya Hidenori , Maruyama Soichi , Mikami Takeshi , Sekizaki Tsutomu
Published: April 2003

Erysipelothrix rhusiopathiaeis a gram-positive bacterium that causes erysipelas in animals and erysipeloid in humans. We found two adhesive surface proteins ofE. rhusiopathiaeand determined the nucleotide sequences of the genes, which were colocalized and designatedrspAandrspB. The two genes were present in all of the serovars ofE. rhusiopathiaestrains examined. The deduced RspA and RspB proteins contain the C-terminal anchoring motif, LPXTG, which is preceded by repeats of consensus amino acid sequences. The consensus sequences are composed of 78 to 92 amino acids and repeat 16 and 3 times in RspA and RspB, respectively. Adhesive surface proteins of other gram-positive bacteria, includingListeria monocytogenesadhesin-like protein,Streptococcus pyogenesprotein F2 and F2-like protein,Streptococcus dysgalactiaeFnBB, andStaphylococcus aureusCna, share the same consensus repeats. Furthermore, the N-terminal regions of RspA and RspB showed characteristics of the collagen-binding domain that was described for Cna. RspA and RspB were expressed inEscherichia colias histidine-tagged fusion proteins and purified. The recombinant proteins showed a high degree of capacity to bind to polystyrene and inhibited the binding ofE. rhusiopathiaeonto the abiotic surface in a dose dependent manner. In a solid-phase binding assay, both of the recombinant proteins bound to fibronectin, type I and IV collagens, indicating broad spectrum of their binding ability. It was suggested that both RspA and RspB were exposed on the cell surface ofE. rhusiopathiae, as were the bacterial cells agglutinated by the anti-RspA immunoglobulin G (IgG) and anti-RspB IgG. RspA and RspB were present both in surface-antigen extracts and the culture supernatants ofE. rhusiopathiaeFujisawa-SmR (serovar 1a) and SE-9 (serovar 2). The recombinant RspA, but not RspB, elicited protection in mice against experimental challenge. These results suggest that RspA and RspB participate in initiation of biofilm formation through their binding abilities to abiotic and biotic surfaces.
Complete Genome Sequence of the Ammonia-Oxidizing Bacterium and Obligate Chemolithoautotroph
Nitrosomonas europaea
Authors: Chain Patrick , Lamerdin Jane , Larimer Frank , Regala Warren , Lao Victoria , Land Miriam , Hauser Loren , Hooper Alan , Klotz Martin , Norton Jeanette , Sayavedra-Soto Luis , Arciero Dave , Hommes Norman , Whittaker Mark , Arp Daniel
Published: April 2003

Nitrosomonas europaea
(ATCC 19718) is a gram-negative obligate chemolithoautotroph that can derive all its energy and reductant for growth from the oxidation of ammonia to nitrite.
Nitrosomonas europaea
participates in the biogeochemical N cycle in the process of nitrification. Its genome consists of a single circular chromosome of 2,812,094 bp. The GC skew analysis indicates that the genome is divided into two unequal replichores. Genes are distributed evenly around the genome, with ∼47% transcribed from one strand and ∼53% transcribed from the complementary strand. A total of 2,460 protein-encoding genes emerged from the modeling effort, averaging 1,011 bp in length, with intergenic regions averaging 117 bp. Genes necessary for the catabolism of ammonia, energy and reductant generation, biosynthesis, and CO
2
and NH
3
assimilation were identified. In contrast, genes for catabolism of organic compounds are limited. Genes encoding transporters for inorganic ions were plentiful, whereas genes encoding transporters for organic molecules were scant. Complex repetitive elements constitute ca. 5% of the genome. Among these are 85 predicted insertion sequence elements in eight different families. The strategy of
N. europaea
to accumulate Fe from the environment involves several classes of Fe receptors with more than 20 genes devoted to these receptors. However, genes for the synthesis of only one siderophore, citrate, were identified in the genome. This genome has provided new insights into the growth and metabolism of ammonia-oxidizing bacteria.
Escherichia coli phnN
, Encoding Ribose 1,5-Bisphosphokinase Activity (Phosphoribosyl Diphosphate Forming): Dual Role in Phosphonate Degradation and NAD Biosynthesis Pathways
Authors: Hove-Jensen Bjarne , Rosenkrantz Tina J. , Haldimann Andreas , Wanner Barry L.
Published: April 2003

An enzymatic pathway for synthesis of 5-phospho-
d
-ribosyl α-1-diphosphate (PRPP) without the participation of PRPP synthase was analyzed in
Escherichia coli
. This pathway was revealed by selection for suppression of the NAD requirement of strains with a deletion of the
prs
gene, the gene encoding PRPP synthase (B. Hove-Jensen, J. Bacteriol. 178:714-722, 1996). The new pathway requires three enzymes: phosphopentomutase, ribose 1-phosphokinase, and ribose 1,5-bisphosphokinase. The latter activity is encoded by
phnN
; the product of this gene is required for phosphonate degradation, but its enzymatic activity has not been determined previously. The reaction sequence is ribose 5-phosphate → ribose 1-phosphate → ribose 1,5-bisphosphate → PRPP. Alternatively, the synthesis of ribose 1-phosphate in the first step, catalyzed by phosphopentomutase, can proceed via phosphorolysis of a nucleoside, as follows: guanosine + P
i
→ guanine + ribose 1-phosphate. The ribose 1,5-bisphosphokinase-catalyzed phosphorylation of ribose 1,5-bisphosphate is a novel reaction and represents the first assignment of a specific chemical reaction to a polypeptide required for cleavage of a carbon-phosphorus (C—P) bond by a C-P lyase. The
phnN
gene was manipulated in vitro to encode a variant of ribose 1,5-bisphosphokinase with a tail consisting of six histidine residues at the carboxy-terminal end. PhnN was purified almost to homogeneity and characterized. The enzyme accepted ATP but not GTP as a phosphoryl donor, and it used ribose 1,5-bisphosphate but not ribose, ribose 1-phosphate, or ribose 5-phosphate as a phosphoryl acceptor. The identity of the reaction product as PRPP was confirmed by coupling the ribose 1,5-bisphosphokinase activity to the activity of xanthine phosphoribosyltransferase in the presence of xanthine, which resulted in the formation of 5′-XMP, and by cochromatography of the reaction product with authentic PRPP.
Glucose-Related Dissociation between
icaADBC
Transcription and Biofilm Expression by
Staphylococcus epidermidis
: Evidence for an Additional Factor Required for Polysaccharide Intercellular Adhesin Synthesis
Authors: Dobinsky Sabine , Kiel Kathrin , Rohde Holger , Bartscht Katrin , Knobloch Johannes K.-M. , Horstkotte Matthias A. , Mack Dietrich
Published: April 2003

Biofilm formation in
Staphylococcus epidermidis
depends, in the majority of the strains, on the activity of the
icaADBC
locus. The expression of the operon that encodes the synthetic enzymes of the intercellular polysaccharide adhesin (PIA) depends on a variety of exogenic environmental conditions and is, at least in part, regulated by the alternative sigma factor σ
B
. We investigated the transcriptional regulation of the
ica
operon and the respective phenotypes expressed under growth conditions differing in the content of glucose in the growth medium. In the presence of glucose,
S. epidermidis
exhibited a PIA- and biofilm-positive phenotype whereas
ica
transcription was down-regulated in the postexponential and stationary phases of growth. Surprisingly, maximum transcription of
ica
was detectable in the stationary phase of growth in the absence of glucose despite the expression of a PIA- and biofilm-negative phenotype. In vitro enzymatic assays and phenotypic characterization showed that the abundant amount of
ica
mRNA was functionally active because induction of stationary-phase cells with glucose led to immediate PIA synthesis. Induction of biofilm formation could be completely inhibited by chloramphenicol, which, given at a later stage of biofilm accumulation, also inhibited further development of preformed biofilm, indicating that continuous translation of an additional,
icaADBC
-independent factor is required for the expression of a biofilm-positive phenotype.
The
fdxA
Ferredoxin Gene Can Down-Regulate
frxA
Nitroreductase Gene Expression and Is Essential in Many Strains of
Helicobacter pylori
Authors: Mukhopadhyay Asish K. , Jeong Jin-Yong , Dailidiene Daiva , Hoffman Paul S. , Berg Douglas E.
Published: April 2003

Very few examples of metabolic regulation are known in the gastric pathogen
Helicobacter pylori
. An unanticipated case was suggested, however, upon finding two types of metronidazole (Mtz)-susceptible strains: type I, in which
frxA
(which encodes a nitroreductase that contributes to Mtz susceptibility) is quiescent, and type II, in which
frxA
is well expressed. Here we report that inactivation of the
fdxA
ferredoxin gene (
hp277
) in type I strains resulted in high-level
frxA
expression (in effect, making them type II). However,
fdxA
null derivatives were obtained from only 6 of 32 type I strains tested that were readily transformed with an
frxA
::
aphA
marker. This suggested that
fdxA
is often essential. This essentiality was overcome in 4 of 20 strains by inactivating
frxA
, which suggested both that
frxA
overexpression is potentially deleterious and also that
fdxA
has additional, often vital roles. With type II strains, in contrast,
fdxA
null derivatives were obtained in 20 of 23 cases tested. Thus,
fdxA
is dispensable in most strains that normally exhibit (and tolerate) strong
frxA
expression. We propose that restraint of
frxA
expression helps maintain balanced metabolic networks in most type I strains, that other homeostatic mechanisms predominate in type II strains, and that these complex results constitute a phenotypic manifestation of
H. pylori
's great genetic diversity.
Bone Morphogenetic Proteins, Their Antagonists, and the Skeleton
Authors: Canalis Ernesto , Economides Aris N. , Gazzerro Elisabetta
Published: April 2003

Skeletal homeostasis is determined by systemic hormones and local factors. Bone morphogenetic proteins (BMP) are unique because they induce the differentiation of mesenchymal cells toward cells of the osteoblastic lineage and also enhance the differentiated function of the osteoblast. However, the activity of BMPs needs to be tempered by intracellular and extracellular antagonists. BMPs bind to specific receptors and signal by phosphorylating the cytoplasmic proteins mothers against decapentaplegic (Smad) 1 and 5, which form heterodimers with Smad 4, and after nuclear translocation regulate transcription. BMP antagonists can be categorized as pseudoreceptors that compete with signaling receptors, inhibitory Smads that block signaling, intracellular binding proteins that bind Smad 1 and 5, and factors that induce ubiquitination and proteolysis of signaling Smads. In addition, a large number of extracellular proteins that bind BMPs and prevent their binding to signaling receptors have emerged. They are the components of the Spemann organizer, noggin, chordin, and follistatin, members of the Dan/Cerberus family, and twisted gastrulation. The antagonists tend to be specific for BMPs and are regulated by BMPs, indicating the existence and need of local feedback mechanisms to temper BMP cellular activities.
The Pentalfa project. 2: Profile of participants and economic aspects
Authors: Himpens B
Published: April 2003

A distance continuing medical education programme was established at the Katholieke Universiteit Leuven using multipoint videoconferencing via ISDN lines at 384 kbit/s. During each of the first three academic years of the project, two or three periods of eight or nine sessions each were organized (a total of 74 sessions). A questionnaire was given to all participants to determine the profile of the users and the efficiency of the project. Sixty-five per cent of the participants were male. The proportion of female participants was higher at the central location than at the peripheral sites. The mean age of the participants was 37.7 years (SEM 0.3). Male participants were older than female ones. At the central location, the mean age was lower than at the peripheral locations. Nearly 90% of the participants at the peripheral sites said that they saved time by attending a videoconference session. The average time saving per participant at the peripheral locations increased from 99 min in the first year to 145 min in the third year of the project. The time saving was closely related to the distance between the peripheral location and the central location. The global cost per participant at the peripheral locations was 43.7 Euros per hour of broadcasting and the indirect estimated cost-saving was 64 Euros per hour. More than 85% of the participants at the peripheral sites stated that they would no longer travel to Leuven (the central location) for these sessions if they were to be organized in a traditional, face-to-face manner, mostly because of the time required, particularly in road travel.
Picture archiving and fundus imaging in a glaucoma clinic
Authors: Lamminen Heikki
Published: April 2003

Ophthalmological image archiving and distribution can be automated using a picture archiving and communication system (PACS). A fundus PACS has been in clinical use since February 2000 at the ophthalmology clinic of Tampere University Hospital. It consists of a digital fundus camera, an imaging workstation, from which new patients can be added to the archive, 10 viewing stations and an image archive server. In glaucoma imaging, the fundus images taken from a patient are transferred from the imaging workstation to the image archive server and are then immediately available from the physician's viewing workstation; the transfer time of an average image, of 350 kbit, is 0.0035 s, even though the archive is located 5 km away. After 18 months of operation there were over 16,000 images archived; these took 5.3 GByte of a total storage capacity of 41.9 GByte. The network and archive server achieved 99% reliability in use. Digital imaging makes it possible to shift ophthalmology clinics towards more patient-oriented treatment procedures.
Intensive telehealth management of five at-risk adolescents with diabetes
Authors: Gelfand Kenneth , Geffken Gary , Halsey-Lyda Martha , Muir Andrew , Malasanos Toree
Published: April 2003

Five adolescents with diabetes participated in an intensive outpatient treatment programme designed to improve adherence to their regimen and improve metabolic control. Families reported blood sugar levels, injections and food intake daily by telephone. After four weeks they were offered a video-phone. Nine subjects were recruited but four of them dropped out. Of the remaining five, one subject used a video-phone and one subject reported blood sugar results by email. Most of the children improved their metabolic control and all five subjects showed reduced HbA1c levels during the three months of the study. The use of telehealth facilitated the treatment of adolescents with poor glycaemic control.
Implicating trust in the innovation process†
Authors: Clegg Chris , Unsworth Kerrie , Epitropaki Olga , Parker Giselle
Published: April 2003

In this paper, we describe the development of two new measures of innovation trust, ‘trust that heard’ and ‘trust that benefit’. We report the findings from their use in a survey of design engineers in two large aerospace companies. We test a range of hypotheses covering different plausible roles for trust and confirm a ‘main effects’ model, whereby the variables predict the number of ideas suggested and the number of ideas implemented. In addition, we replicate earlier findings by Axtel et al. (2000), namely that personal and job variables predict idea suggestion, whereas organizational variables predict implementation.
Newcomer adjustment: The relationship between organizational socialization tactics, information acquisition and attitudes
Authors: Cooper‐Thomas Helena , Anderson Neil
Published: April 2003

A longitudinal study was designed to investigate relationships between socialization tactics, information acquisition, and attitudinal outcomes associated with successful organizational socialization. The research was conducted over three measurements with British Army recruits during their first 8 weeks of training. The key finding is the confirmation that information acquisition mediates the relationship between organizational socialization tactics and key socialization outcomes in terms of newcomer attitudes. These results strengthen the conception of organizational socialization as primarily a learning process. In addition, these results importantly show the rapidity with which newcomers can adjust during organizational socialization.
Effects of attitude dissimilarity and time on social integration: A longitudinal panel study
Authors: Van der Vegt Gerben S.
Published: April 2003

A longitudinal panel study in 25 work groups of elementary school teachers examined the effect of attitudinal dissimilarity and time on social integration across a 9‐month period. In line with the prediction based on both the similarity‐attraction approach and social identity theory, cross‐lagged regression and LISREL analyses showed that attitudinal dissimilarity decreased social integration rather than the other way around. In addition, results showed that this effect was not stronger for group members who had spent a longer period of time with the other group members. Finally, mediated regression analyses revealed that attitude dissimilarity did not mediate the effect of time on social integration.
The effects of organizational and individual factors on occupational accidents
Authors: Oliver Amparo , Cheyne Alistair , Tomás Jose M. , Cox Sue
Published: April 2003

This study examined the relationships between individual psychological, work environment and organizational variables and occupational accidents using structural equation modelling with latent variables. A series of nested explicative models of the relationships between these variables was derived. Data were collected from a wide range of industrial sectors in the Valencia region of Spain using structured interviews. In total, 525 valid questionnaires were completed and these formed the basis for the subsequent analyses. Analysis showed that the model in the series that proposed relationships between all the latent variables provided the best representation of the data. This supported the broad hypothesis that each of the variables has an effect on accidents and also showed that the individual level variables, including safe behaviour and general heath, mediate the indirect effects from the organizational variables. The final model showed that individual safe behaviour is strongly predicted within the model, although it is mainly related to organizational involvement in safety and not directly to perceptions of the physical work environment. An important role is played in the final model by participants' evaluations of organizational involvement in safety and this is consistent with earlier work highlighting the importance of management commitment to, and action on, safety issues. Finally, the model supported the proposal that stress processes mediate the effects of both organizational and environmental variables.
A critical re‐examination and analysis of cognitive ability tests using the Thorndike model of fairness
Authors: Chung‐Yan Greg A. , Cronshaw Steven F.
Published: April 2003

The literature investigating the bias of cognitive ability tests (CATs) is often conflated with the controversy surrounding which method for determining test bias is superior. The general acceptance of the Cleary (1968) model of test bias in industrial/organizational psychology has served to deter evaluations of tests against other models of test bias because acceptance of the Cleary model as ‘superior’ implies the limited relevance of investigations of tests against other models of bias. Although these other models are not considered to be models of predictive bias in the psychometric sense, they nonetheless have significant implications for workplace diversity. Most notably, the existing literature lacks the precision and depth necessary to extrapolate the actual false‐rejection rate in selection decisions that burden visible minority groups when CATs are used. The current study identifies these gaps in the literature in addition to evaluating CATs against the Thorndike (1971) model of test bias. Results indicate that a one standard deviation (SD) difference in Black‐White CAT scores is associated with a Black‐White difference in job performance of approximately 1/3 SD. The Black‐White difference in job performance is reduced to approximately 1/10 SD when objective, rather than subjective, job performance criteria are used. We therefore conclude that CATs are biased against Blacks when evaluated using the Thorndike model. The implications for use of CATs in personnel selection are discussed.
Social comparison in virtual work environments: An examination of contemporary referent selection
Authors: Conner Deondra S.
Published: April 2003

The current trend with organizations is to streamline operations, cut cost, and operate with fewer employees (i.e., to do more with less). This trend has encouraged events such as downsizing and mergers as well as fostered the development of virtual work environments and new organizational forms like virtual organizations. Consequently, this change in organizational forms and the context of work has the potential to cause other associated consequences. One possible consequence is a change in the availability and type of referent others available. Likewise, a better understanding of worker referent choice remains a common issue of debate among researchers of comparison theories. This paper examines how referent selection relative to worker social comparison is (and will be) affected by the changing nature of organizations and the context of work.
Successful treatment of a patient with hairy cell leukemia and pentostatin‐induced autoimmune thrombocytopenia with rituximab
Authors: Hensel Manfred , Ho Anthony D.
Published: April 2003

The treatment of choice for hairy cell leukemia (HCL) are the purine analogs pentostatin and cladribine. They induced complete remissions in up to 85% of patients. Purine analogs are known to induce autoimmune phenomena, but there are no reports of autoimmune thrombocytopenia after treatment with pentostatin. This case report describes the very rare association of pentostatin‐treated hairy cell leukemia and autoimmune thrombocytopenia. Encouraged by first reports of promising activity of the anti‐CD20 monoclonal antibody rituximab in patients with autoimmune disorders, we decided to treat our patient with rituximab in the conventional dose of 375 mg/m2 i.v. weekly for 4 cycles. One week after the first administration, the peripheral blood count has recovered with a normal platelet count. 22 weeks after completion of therapy, the patient is still in complete hematologic remission without further medication. In conclusion, rituximab seems to be a new, promising drug in the treatment of refractory autoimmune thrombocytopenia even in patients with underlying lymphoproliferative disorders. Am. J. Hematol. 73:37–40, 2003. © 2003 Wiley‐Liss, Inc.
Alleviation of systemic manifestations of multicentric Castleman's disease by thalidomide
Authors: Lee Fa‐Chyi , Merchant Shakil H.
Published: April 2003

Multicentric Castleman's disease (MCD) is a rare lymphoproliferative disorder of unknown etiology. Although HHV‐8 (human herpesvirus type 8) has been suggested as a possible etiologic agent in a subpopulation of cases, appropriate treatment of the HHV‐8 infection has not produced regression of the disease. Additionally, other treatment modalities, including steroids and various regimens of chemotherapy, do not consistently provide good control of the disease. Clinical signs and symptoms of the disease are primarily mediated by cytokines, especially interleukin‐6 (IL‐6). We report a case of multicentric Castleman's disease that responded dramatically to single agent thalidomide. A powerful cytokine disruptor, thalidomide may have good therapeutic efficacy in treating MCD and related cytokine‐mediated disorders. Am. J. Hematol. 73:48–53, 2003. © 2003 Wiley‐Liss, Inc.
Idiopathic autoimmune thrombocytopenia: Evidence for redistribution of platelet antibodies into the circulation after immunoadsorption treatment
Authors: Leitner G.C. , Stiegler G. , Horvath M. , Hoecker P. , Sagaster P. , Panzer S.
Published: April 2003

Platelet antibodies are detectable in only about 50% of patients with chronic autoimmune thrombocytopenia (AITP). We determined platelet antibodies against GPIa/IIa, GPIb/IX, GPIIb/IIIa, and GPV and reticulated platelets in three female patients with AITP, before and after immunoadsorption treatment. None of the three patients' sera contained platelet antibodies prior to treatment. Thereafter, anti‐GPIIb/IIIa, anti‐GPIb/IX (n = 3), and anti‐GPV (n = 1) were detectable in the patients' sera. These antibody specificities were also found in the eluates from the immunoadsorption columns. Only one patient had elevated levels of reticulated platelets. Immunoadsorption treatment did not induce a sustained increase of platelet counts in any patient. Immunoadsorption treatment in AITP can induce redistribution of antibodies into the circulation. Am. J. Hematol. 73:44–47, 2003. © 2003 Wiley‐Liss, Inc.
Effects of human mast cell tryptase and eosinophil granule proteins on the kinetics of blood clotting
Authors: Samoszuk Michael , Corwin Mark , Hazen Stanley L.
Published: April 2003

Hypereosinophilic syndromes are often associated with thrombosis through unclear mechanisms, and mastocytosis has been associated with a variety of bleeding disorders. The present studies were aimed at defining the roles and interactions of eosinophil and mast cell constituents on the kinetics of blood clotting as measured by thromboelastograms. Eosinophil granule proteins and purified eosinophil peroxidase markedly reduced the anticoagulant properties of the mast cell tryptase/heparin complex. Moreover, eosinophil peroxidase by itself functioned as a powerful procoagulant and also inhibited the anticoagulant actions of heparin in a chromogenic assay for antithrombin III/factor Xa activity. The anticoagulant activity of the tryptase/heparin complex was attributable exclusively to the associated heparin and not to the intrinsic enzymatic activity of tryptase. Eosinophil granule proteins also strongly inhibited the enzymatic activity of tryptase in the presence of hydrogen peroxide, thus implicating a critical role for eosinophil peroxidase. We conclude that eosinophil granule proteins and eosinophil peroxidase both function as powerful procoagulants and also inhibit the anticoagulant and enzymatic activities of mast cell tryptase. The present results thus provide a mechanistic rationale for the well‐established link between certain eosinophilic inflammatory disorders and hypercoagulant states. They also suggest that eosinophils may play an important role in neutralizing the anticoagulant activity of mast cell tryptase/heparin in various diseases. Am. J. Hematol. 73:18–25, 2003. © 2003 Wiley‐Liss, Inc.
Gaschromatographische trennung und bestimmung von oligostyrolen
Authors: Braun Von Dietrich , Meier Werner
Published: April 2003

Kationisch erhaltene Gemische aus Styrol und Oligostyrolen mit Polymerisations‐graden von 2 bis 5 lassen sich durch temperaturprogrammierte Gaschromatographie trennen. Mit dem gleichen Verfahren kann auch der Gehalt an Styrol und Oligostyrolen in radikalisch hergestellten technischen Polystyrolen ermittelt werden. Hierbei ergibt sich, daß bei der Bestimmung von Styrol in Polystyrol nach DIN 53719 auch ungesättigte Oligomere erfaßt werden. Die Summe des gaschromato‐graphisch bestimmten Monomer‐ und Oligomergehaltes stimmt mit dem nach DIN 53718 erhaltenen methanollöslichen Anteil überein.
Zur phasentrennung von polymergemischen in lösung
Authors: Fuchs Von O.
Published: April 2003

Gemische aus zwei verschiedenen Polymeren in einem gemeinsamen Lösungsmittel sind in den weitaus meisten Fällen miteinander unverträglich. Diese Unverträglichkeit äußert sich in einer starken Trübung beim Ansetzen der Mischung; beim Stehenlassen bilden sich zwei Schichten. Wird die trübe Mischung mit dem gleichen Lösungsmittel verdünnt, so verschwindet bei einer bestimmten Gesamtkonzentration ckr die Trübung, da die Polymeren bei ckr und darunter miteinander verträglich sind. Im Prinzip treten bei Polymermischungen im festen Zustand, den sogenannten Blends, die gleichen Entmischungsvorgänge infolge Unverträglichkeit auf; allerdings ist hier ein Zusammenfließen zusammengehöriger Mikrophasen wegen deren hoher Viskosität nicht möglich.

Über die Zusammensetzung der oberhalb ckr entstehenden zwei Phasen ist bisher wenig bekannt geworden. Wir untersuchten daher, wie sich zwei verschiedene Polymere hinsichtlich Menge und Molekulargewicht auf beide Phasen im gelösten Zustand verteilen. Variiert wurden bei diesen Versuchen das Mischungsverhältnis beider Polymerer, das Molekulargewicht, die Gesamtkonzentration und die Natur des Lösungsmittels. Die Versuche wurden unter Verwendung von Polystyrol und Polyvinylacetat ausgeführt, da sich beide Polymere, die ja in beiden Schichten enthalten sein können, leicht wieder voneinander trennen lassen; diese Trennung wurde für beide Schichten ausgeführt.

Es wurde so gefunden: Jede Schicht enthält beide Polymere. Bei der Phasentrennung findet eine Fraktionierung nach dem Molekulargewicht für beide Polymere statt. Die Verteilung der Polymeren auf die zwei Schichten nach Menge, Molekulargewicht und Konzentration der Polymeren wird außer von der Ausgangskonzentration, dem Molekulargewicht und dem Mengenverhältnis der Polymeren auch von dem unterschiedlichen Solvatationszustand der Makromoleküle in den einzelnen Lösungsmitteln bestimmt. Bei Verwendung von Mischlösungsmitteln findet zusätzlich eine teilweise Trennung auch der Lösungsmittel auf beide Schichten statt.
A kinetic study on the reaction of dicumyl peroxide with some low‐olefin rubbers
Authors: Imoto Minoru , Takemoto Kiichi , Kono Masatsugu
Published: April 2003

The viscosity lowering of toluene solutions of isobutylene‐isoprene rubber, polyisobutylene, and ethylene‐propylene rubber in the reaction with dicumyl peroxide was investigated. By using the kinetic equations for the reaction of rubber with peroxide which had been derived previously by KIRIYAMA et al. the results of the experiments are discussed.
Principles of gel chromatography and possibilities for its development
Authors: Heitz W. , Kern W.
Published: April 2003

Gel chromatography can be considered as a network‐limited partition. This leads to the conclusion that it is impossible to find a generalizing relationship between the molecular weight and the elution volume using parameters depending only on the solute.

The preparation of gels with different chemical structure is discussed and possible methods for the alteration of pore size are described. Investigations of the influence of the physical and chemical structure on separation and separation efficiency have shown that the elution volume depends to some extent on the chemical nature, but the separation efficiency is mainly a function of the physical structure.
Untersuchung über die agglomeration von polymerisatlatices
Authors: Keppler Von H.‐G. , Wesslau H. , Stabenow J.
Published: April 2003

Polymerisatdispersionen sind selbst dann, wenn sie mit demselben Emulgator hergestellt worden sind, nicht immer miteinander verträglich. Enthält das Polymerisat der einen Dispersion hydrophile Gruppen, etwa durch Mitverwendung kleiner Mengen wasserlöslicher Monomerer bei der Emulsionspolymerisation (Typ „A”︁), und enthält das andere keine derartigen Gruppen (Typ „S”︁), so koaguliert eine Mischung der beiden Dispersionen oft schon wenige Sekunden nach ihrer Herstellung. Ein Zusatz von wenigen Prozent des Typs „A”︁ vermag indessen eine Agglomeration der Teilchen einer Dispersion „S”︁ herbeizuführen. Mischt man beispielsweise eine Polybutylacrylatdispersion, deren Teilchen im Durchschnitt einen Durchmesser D̄w von 800 Å haben, mit 1 Gewichtsprozent der Dispersion eines Copolymerisates aus 95% Äthylacrylat und 5% Acrylsäure und stellt den pH‐Wert auf 8–9 ein, so resultiert ein Latex mit folgenden Kenndaten: D̄n = 6300 Å; D̄w = 7300 Å. Das Wachstum der Teilchen setzt sich fort bei weiterer Zugabe einer beliebigen Dispersion des Typs „S”︁.

An Hand von Verteilungsfunktionen der Teilchendurchmesser und mit Hilfe von Latices, die mit polymerisierbaren Farbstoffen indiziert waren, sowie unter Verwendung von elektronenmikroskopischen Aufnahmen mit spezieller Präpariertechnik wurden Vorstellungen über den Agglomerationsmechanismus entwickelt. Danach sind die Latexteilchen durch ihre Emulgatorhülle nur bedingt gegen Assoziat‐(Koagulat‐)bildung geschützt. Treffen Latexteilchen des Typs „S”︁ nur auf ihresgleichen, so bildet die durch den Emulgator aufgebaute elektrische Doppel‐schicht ausreichenden Schutz gegen Koagulation. Treffen Teilchen des Typs „S”︁ auf solche vom Typ „A”︁, so erfolgt irreversible Assoziation. Jedeszufälligaufdie Ober‐fläche von Teilchen „A”︁ auftreffende Teilchen „S”︁ wird festgehalten und verschmilzt mit anderen Teilchen „S”︁ zum Sekundärteilchen, auf dessen Oberfläche das hydrophile Teilchen „A”︁ „schwimmt”︁. Es bleibt dort praktisch unbegrenztwirksam und nimmt jederzeit neu hinzugefügte Teilchen des Typs „S”︁ auf.
Zur oligomerenbildung bei der thermischen polymerisation von styrol
Authors: Stein Von D. J. , Mosthaf H.
Published: April 2003

Die mit der thermischen Polymerisation von Styrol einhergehende Oligomerisierung führt zu vier Dimeren und sechs Trimeren. Mit zunehmender Temperatur wird das Verhältnis von Oligomerisierung zu Polymerisation zugunsten der Oligomerisierung verschoben. Auch die Mengenanteile der Oligomeren untereinander sind von der Temperatur abhängig.
Elektrochemisch initiierte polymerisation von acrylnitril
Authors: Beck Von F. , Leitner H.
Published: April 2003

Durch eine elektrolytisch gestartete Reaktion von reinem Acrylnitril in Gegenwart von 0,1 bis 1% Wasser und in Anwesenheit geringer Mengen eines quartären Ammoniumsalzes wurde ein oligomeres, acetonlösliches, gelbgefärbtes Produkt erhalten, dessen Molgewicht zwischen 1000 und 3000 liegt. Die hohe Stromausbeute ‐ sie erreichte 100g/Ah, d. h. es wurden pro Elektronentransfer bis zu 2 Polymermoleküle gebildet ‐, das niedere Molgewicht, die Unabhängigkeit des Molgewichts von der Stromdichte, die Unempfindlichkeit gegen Sauerstoff sowie Co‐polymerisationsversuche mit Styrol lassen darauf schließen, daß das Oligomere an der Kathode durch einen anionischen Mechanismus entstehen muß. Der Einfluß der Art des Leitsalzes, der Kathode, der Stromdichte, der Wasserkonzentration, der Konvektion und der Temperatu auf die Oligomerenbildung wurden untersucht. Ein Strukturvorschlag wird zur Diskussion gestellt.
Die anwendung von redoxharzen in der anorganischen chemie
Authors: Manecke Von Georg , Kossmehl Gerhard , Hartwich Günther , Gawlik Regina
Published: April 2003

Ein das Anthrachinon‐Anthrahydrochinon‐System enthaltendes Redoxharz wurde zur Abscheidung von Ag, Cu, Te und Se aus wäßriger Lösung eingesetzt. Ag, Cu und Te wurden in 1 n HNO3 und Se in KCN‐Lösung gelöst. Mit diesem Harz wurden auch Ionenumladungen (UO2+2 → V4+ und VO−2 → V3+) vorgenommen. Mit einem Kondensationsharz aus Hydrochinon, Phenol und Formaldehyd konnten in einem kontinuierlichen Verfahren bis zu 1,3 n H2O2‐Lösungen hergestellt werden.