bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of human cytomegalovirus DNA replication in non-permissive Vero and 293 cells
Authors: Ellsmore Victoria , Reid G. Gordon , Stow Nigel D.
Published: February 2003

Human cytomegalovirus (HCMV) displays an exceptionally restricted host range in tissue culture with human fibroblasts being the principal fully permissive system. Nevertheless, immediate early (IE) proteins are expressed following infection of many non-permissive cell types of human, simian and murine origin, and viral origin-dependent DNA synthesis has been reconstituted by transfection of plasmids into Vero cells, a non-permissive line from African green monkey. We have examined the accumulation of HCMV strain AD169 DNA, and the replication of transfected HCMV origin-containing plasmids, in infected Vero and human embryonic kidney 293 cells, which were previously reported to express the major IE protein in a small proportion of infected cells but to be non-permissive for viral DNA synthesis. In Vero cells accumulation of origin-containing plasmid but not viral DNA occurred, whilst in 293 cells both DNAs accumulated. Immunofluorescence experiments indicated that following infection with 3 p.f.u. per cell, a small fraction of both cell types expressed the UL44 DNA replication protein. Neither cell line, however, supported the generation of infectious progeny virus. These results suggest that IE proteins expressed in Vero and 293 cells can induce the synthesis of early proteins capable of functioning in viral DNA replication, but there is a failure in later events on the pathway to infectious virus production. This provides further support for transfected Vero cells being a valid system in which to study HCMV DNA synthesis, and suggests that 293 cells may also prove useful in similar experiments.
Induction of apoptosis in an insect cell line, IPLB-Ld652Y, infected with nucleopolyhedroviruses
Authors: Ishikawa Hiroki , Ikeda Motoko , Yanagimoto Kenichi , Alves Cristiano A. Felipe , Katou Yasuhiro , Laviña-Caoili Barbara A. , Kobayashi Michihiro
Published: February 2003

Ld652Y cells derived from the gypsy moth, Lymantria dispar, were infected with seven different nucleopolyhedroviruses (NPVs) including those from Autographa californica, Bombyx mori (BmNPV), Hyphantria cunea (HycuNPV), Spodoptera exigua (SeMNPV), L. dispar, Orgyia pseudotsugata (OpMNPV) and Spodoptera litura (SpltMNPV). The results showed that Ld652Y cells infected with BmNPV, HycuNPV, SeMNPV, OpMNPV and SpltMNPV underwent apoptosis, displaying apoptotic bodies, characteristic DNA fragmentation and increased caspase-3-like protease activity; HycuNPV induced the most severe apoptosis. In HycuNPV-infected Ld652Y cells, a considerable amount of viral DNA was synthesized although there was no detectable yield of budded virions and polyhedrin. Northern blot and immunoblot analyses revealed that HycuNPV inhibitor of apoptosis 3 (IAP3), which has been shown to function in Sf9 cells, was expressed in HycuNPV-infected Ld652Y cells at a level higher than or comparable with that in HycuNPV-infected SpIm cells, which produced a high titre of progeny virions without any apoptotic response. These results imply that the relative ease of apoptosis induction in NPV-infected Ld652Y cells is largely dependent on inherent cellular properties rather than functions of the respective NPVs, and indicate that the defect in progeny virion production is not merely due to the virus-induced apoptosis in HycuNPV-infected Ld652Y cells.
Homology between the human cytomegalovirus RL11 gene family and human adenovirus E3 genes
Authors: Davison Andrew J. , Akter Parvis , Cunningham Charles , Dolan Aidan , Addison Clare , Dargan Derrick J. , Hassan-Walker Aycan F. , Emery Vincent C. , Griffiths Paul D. , Wilkinson Gavin W. G.
Published: February 2003

A significant proportion of the human cytomegalovirus (HCMV) genome comprises 12 multigene families that probably arose by gene duplication. One, the RL11 family, contains 12 members, most of which are predicted to encode membrane glycoproteins. Comparisons of sequences near the left end of the genome in several HCMV strains revealed two adjacent open reading frames that potentially encode related proteins: RL6, which is hypervariable, and RL5A, which has not been recognized previously. These genes potentially encode a domain that is the hallmark of proteins encoded by the RL11 family, and thus constitute two new members. A homologous domain is also present in a subset of human adenovirus E3 membrane glycoproteins. Evolution of genes specifying the shared domain in cytomegaloviruses and adenoviruses is characterized by extensive divergence, gene duplication and selective sequence loss. These features prompt speculation about the roles of these genes in the two virus families.
Delineation of sequences important for efficient packaging of feline immunodeficiency virus RNA
Authors: Browning Matthew T. , Mustafa Farah , Schmidt Russell D. , Lew Kathy A. , Rizvi Tahir A.
Published: February 2003

We have used systematic deletion analysis of the 5′ untranslated region (UTR) of the feline immunodeficiency virus (FIV) genome, both in the presence and absence of various amounts of gag, to define the cis-acting sequences responsible for efficient RNA packaging. Our analyses revealed that the primary FIV packaging signal consists of two essential core elements located within the first 90–120 bp of the 5′UTR and the first 90 bp of the gag gene. Interestingly, the region between the major splice donor (SD) and gag, including ∼130–160 bp upstream of the SD, is dispensable for encapsidation. Finally, other determinants of packaging were found to be present in the viral LTR and/or within the 3′ end of the viral genome. Taken together, our results suggest that the primary packaging determinants of FIV are multipartite and discontinuous, composed of two elements within the 5′UTR and gag gene.
Analysis of the subcellular localization of hepatitis C virus E2 glycoprotein in live cells using EGFP fusion proteins
Authors: Kien François , Abraham Jean-Daniel , Schuster Catherine , Kieny Marie Paule
Published: February 2003

Hepatitis C virus (HCV) E1 and E2 glycoproteins assemble intracellularly to form a non-covalently linked heterodimer, which is retained in the endoplasmic reticulum (ER). To study the subcellular localization of E2 in live cells, the enhanced green fluorescent protein (EGFP) was fused to the N terminus of E2. Using fluorescence and confocal microscopy, we have confirmed that E2 is located in the ER, where budding of HCV virions is thought to occur. Immunoprecipitation experiments using a conformation-sensitive antibody and a GST pull-down assay showed that fusion of EGFP to E2 interferes neither with its heterodimeric assembly with E1, nor with proper folding of the ectodomain, nor with the capacity of E2 to interact with human CD81, indicating that the EGFP–E2 fusion protein is functional. As a tool to study binding of E2 to target cells, we also described the expression of an EGFP–E2 fusion protein at the cell surface.
Dysfunctionality of a tobacco mosaic virus movement protein mutant mimicking threonine 104 phosphorylation
Authors: Karger E. M. , Frolova O. Yu. , Fedorova N. V. , Baratova L. A. , Ovchinnikova T. V. , Susi P. , Makinen K. , Ronnstrand L. , Dorokhov Yu. L. , Atabekov J. G.
Published: February 2003

Replication of tobacco mosaic virus (TMV) is connected with endoplasmic reticulum (ER)-associated membranes at early stages of infection. This study reports that TMV movement protein (MP)-specific protein kinases (PKs) associated with the ER of tobacco were capable of phosphorylating Thr104 in TMV MP. The MP-specific PKs with apparent molecular masses of about 45–50 kDa and 38 kDa were revealed by gel PK assays. Two types of mutations were introduced in TMV MP gene of wild-type TMV U1 genome to substitute Thr104 by neutral Ala or by negatively charged Asp. Mutation of Thr104 to Ala did not affect the size of necrotic lesions induced by the mutant virus in Nicotiana tabacum Xanthi nc. plants. Conversely, mutation of Thr to Asp mimicking Thr104 phosphorylation strongly inhibited cell-to-cell movement. The possible role of Thr104 phosphorylation in TMV MP function is discussed.
SWI/SNF-dependent chromatin remodeling ofRNR3requires TAFIIs and the general transcription machinery
Authors: Sharma Vishva Mitra , Li Bing , Reese Joseph C.
Published: February 2003

Gene expression requires the recruitment of chromatin remodeling activities and general transcription factors (GTFs) to promoters. Whereas the role of activators in recruiting chromatin remodeling activities has been clearly demonstrated, the contributions of the transcription machinery have not been firmly established. Here we demonstrate that the remodeling of theRNR3promoter requires a number of GTFs, mediator and RNA polymerase II. We also show that remodeling is dependent upon the SWI/SNF complex, and that TFIID and RNA polymerase II are required for its recruitment to the promoter. In contrast, Gcn5p-dependent histone acetylation occurs independently of TFIID and RNA polymerase II function, and we provide evidence that acetylation increases the extent of nucleosome remodeling, but is not required for SWI/SNF recruitment. Thus, the general transcription machinery can contribute to nucleosome remodeling by mediating the association of SWI/SNF with promoters, thereby revealing a novel pathway for the recruitment of chromatin remodeling activities.
p190RhoGAP can act to inhibit PDGF-induced gliomas in mice: a putative tumor suppressor encoded on human Chromosome 19q13.3
Authors: Wolf Rebecca M. , Draghi Nicole , Liang Xiquan , Dai Chengkai , Uhrbom Lene , Eklöf Charlotta , Westermark Bengt , Holland Eric C. , Resh Marilyn D.
Published: February 2003

p190RhoGAP and Rho are key regulators of oligodendrocyte differentiation. The gene encoding p190RhoGAP is located at 19q13.3 of the human chromosome, a locus that is deleted in 50%–80% of oligodendrogliomas. Here we provide evidence that p190RhoGAP may suppress gliomagenesis by inducing a differentiated glial phenotype. Using a cell culture model of autocrine loop PDGF stimulation, we show that reduced Rho activity via p190RhoGAP overexpression or Rho kinase inhibition induced cellular process extension, a block in proliferation, and reduced expression of the neural precursor marker nestin. In vivo infection of mice with retrovirus expressing PDGF and the p190 GAP domain caused a decreased incidence of oligodendrogliomas compared with that observed with PDGF alone. Independent experiments revealed that the retroviral vector insertion site in 3 of 50 PDGF-induced gliomas was within thep190RhoGAPgene. This evidence strongly suggests that p190 regulates critical components of PDGF oncogenesis and can act as a tumor suppressor in PDGF-induced gliomas by down-regulating Rho activity.
Redox regulation of mammalian heat shock factor 1 is essential for Hsp gene activation and protection from stress
Authors: Ahn Sang-Gun , Thiele Dennis J.
Published: February 2003

The activation of eukaryotic heat shock protein (Hsp) gene expression occurs in response to a wide variety of cellular stresses including heat shock, hydrogen peroxide, uncoupled oxidative phosphorylation, infection, and inflammation. Biochemical and genetic studies have clearly demonstrated critical roles for mammalian heat shock factor 1 (HSF1) in stress-inducible Hsp gene expression, resistance to stress-induced programmed cell death, extra-embryonic development, and other biological functions. Activation of mammalian Hsp gene expression involves the stress-inducible conversion of HSF1 from the inactive monomer to the DNA-binding competent homotrimer. Although Hsp activation is a central conserved process in biology, the precise mechanisms for stress sensing and signaling to activate HSF1, and the mechanisms by which many distinct stresses activate HSF1, are poorly understood. In this report we demonstrate that recombinant mammalian HSF1 directly senses both heat and hydrogen peroxide to assemble into a homotrimer in a reversible and redox-regulated manner. The sensing of both stresses requires two cysteine residues within the HSF1 DNA-binding domain that are engaged in redox-sensitive disulfide bonds. HSF1 derivatives in which either or both cysteines were mutated are defective in stress-inducible trimerization and DNA binding, stress-inducible nuclear translocation and Hsp genetrans-activation, and in the protection of mouse cells from stress-induced apoptosis. This redox-dependent activation of HSF1 by heat and hydrogen peroxide establishes a common mechanism in the stress activation of Hsp gene expression by mammalian HSF1.
Impact of p53 loss on reversal and recurrence of conditional Wnt-induced tumorigenesis
Authors: Gunther Edward J. , Moody Susan E. , Belka George K. , Hahn Kristina T. , Innocent Nathalie , Dugan Katherine D. , Cardiff Robert D. , Chodosh Lewis A.
Published: February 2003

Aberrant activation of Wnt signaling is oncogenic and has been implicated in a variety of human cancers. We have developed a doxycycline-inducibleWnt1transgenic mouse model to determine the dependence of established mammary adenocarcinomas on continued Wnt signaling. Using this model we show that targeted down-regulation of the Wnt pathway results in the rapid disappearance of essentially all Wnt-initiated invasive primary tumors as well as pulmonary metastases. Tumor regression does not require p53 and occurs even in highly aneuploid tumors. However, despite the dependence of primary mammary tumors and metastases on continued Wnt signaling and the dispensability of p53 for tumor regression, we find that a substantial fraction of tumors progress to a Wnt-independent state and that p53 suppresses this process. Specifically, loss of onep53allele dramatically facilitates the progression of mammary tumors to aWnt1-independent state both by impairing the regression of primary tumors following doxycycline withdrawal and by promoting the recurrence of fully regressed tumors in the absence of doxycycline. Thus, although p53 itself is dispensable for tumor regression, it nevertheless plays a critical role in the suppression of tumor recurrence. Our findings demonstrate that although even advanced stages of epithelial malignancy remain dependent upon continued Wnt signaling for maintenance and growth, loss of p53 facilitates tumor escape and the acquisition of oncogene independence.
Dynamic regulation of the Ras pathway via proteolysis of the NF1 tumor suppressor
Authors: Cichowski Karen , Santiago Sabrina , Jardim Melanie , Johnson Bryan W. , Jacks Tyler
Published: February 2003

Mutations in theNF1tumor suppressor underlie the familial tumor predisposition syndrome neurofibromatosis type I. Although its encoded protein, neurofibromin, functions as a Ras–GTPase activating protein (GAP), nothing is known about how it is normally regulated or its precise role in controlling Ras signaling pathways. We show here that neurofibromin is dynamically regulated by the ubiquitin-proteasome pathway. Degradation is rapidly triggered in response to a variety of growth factors and requires sequences adjacent to the catalytic GAP-related domain of neurofibromin. However, whereas degradation is rapid, neurofibromin levels are re-elevated shortly after growth factor treatment. Accordingly,Nf1-deficient mouse embryonic fibroblasts (MEFs) exhibit an enhanced activation of Ras, prolonged Ras and ERK activities, and proliferate in response to subthreshold levels of growth factors. Thus, the dynamic proteasomal regulation of neurofibromin represents an important mechanism of controlling both the amplitude and duration of Ras-mediated signaling. Furthermore, this previously unrecognized Ras regulatory mechanism may be exploited therapeutically.
The transcriptional activity of human Chromosome 22
Authors: Rinn John L. , Euskirchen Ghia , Bertone Paul , Martone Rebecca , Luscombe Nicholas M. , Hartman Stephen , Harrison Paul M. , Nelson F. Kenneth , Miller Perry , Gerstein Mark , Weissman Sherman , Snyder Michael
Published: February 2003

A DNA microarray representing nearly all of the unique sequences of human Chromosome 22 was constructed and used to measure global-transcriptional activity in placental poly(A)+RNA. We found that many of the known, related and predicted genes are expressed. More importantly, our study reveals twice as many transcribed bases as have been reported previously. Many of the newly discovered expressed fragments were verified by RNA blot analysis and a novel technique called differential hybridization mapping (DHM). Interestingly, a significant fraction of these novel fragments are expressed antisense to previously annotated introns. The coding potential of these novel expressed regions is supported by their sequence conservation in the mouse genome. This study has greatly increased our understanding of the biological information encoded on a human chromosome. To facilitate the dissemination of these results to the scientific community, we have developed a comprehensive Web resource to present the findings of this study and other features of human Chromosome 22 athttp://array.mbb.yale.edu/chr22.
Protein ISGylation modulates the JAK-STAT signaling pathway
Authors: Malakhova Oxana A. , Yan Ming , Malakhov Michael P. , Yuan Youzhong , Ritchie Kenneth J. , Kim Keun Il , Peterson Luke F. , Shuai Ke , Zhang Dong-Er
Published: February 2003

ISG15 is one of the most strongly induced genes upon viral infection, type I interferon (IFN) stimulation, and lipopolysaccharide (LPS) stimulation. Here we report that mice lacking UBP43, a protease that removes ISG15 from ISGylated proteins, are hypersensitive to type I IFN. Most importantly, in UBP43-deficient cells, IFN-β induces a prolonged Stat1 tyrosine phosphorylation, DNA binding, and IFN-mediated gene activation. Furthermore, restoration of ISG15 conjugation in protein ISGylation-defective K562 cells increases IFN-stimulated promoter activity. These findings identify UBP43 as a novel negative regulator of IFN signaling and suggest the involvement of protein ISGylation in the regulation of the JAK-STAT pathway.
Structure and function of the PWI motif: a novel nucleic acid-binding domain that facilitates pre-mRNA processing
Authors: Szymczyna Blair R. , Bowman John , McCracken Susan , Pineda-Lucena Antonio , Lu Ying , Cox Brian , Lambermon Mark , Graveley Brenton R. , Arrowsmith Cheryl H. , Blencowe Benjamin J.
Published: February 2003

The PWI motif is a highly conserved domain of unknown function in the SRm160 splicing and 3′-end cleavage-stimulatory factor, as well as in several other known or putative pre-mRNA processing components. We show here that the PWI motif is a new type of RNA/DNA-binding domain that has an equal preference for single- and double-stranded nucleic acids. Deletion of the motif prevents SRm160 from binding RNA and stimulating 3′-end cleavage, and its substitution with a heterologous RNA-binding domain restores these functions. The NMR solution structure of the SRm160-PWI motif reveals a novel, four-helix bundle and represents the first example of an α-helical fold that can bind single-stranded (ss)RNA. Structure-guided mutagenesis indicates that the same surface is involved in RNA and DNA binding and requires the cooperative action of a highly conserved, adjacent basic region. Thus, the PWI motif is a novel type of nucleic acid-binding domain that likely has multiple important functions in pre-mRNA processing, including SRm160-dependent stimulation of 3′-end formation.
Identification of genes that protect theC. elegansgenome against mutations by genome-wide RNAi
Authors: Pothof Joris , van Haaften Gijs , Thijssen Karen , Kamath Ravi S. , Fraser Andrew G. , Ahringer Julie , Plasterk Ronald H.A. , Tijsterman Marcel
Published: February 2003

An RNA interference (RNAi)-based genome-wide screen was performed to detect genes that contribute to genome stability in somatic cells ofCaenorhabditis elegans. We identified 61 such genes; these also affect spontaneous mutagenesis in the germ line. Their sequence suggests a role in DNA repair and/or replication, in chromatin remodeling, or in cell cycle control; there are also many novel genes that are highly conserved from yeast to human. Because known mutator genes are causally involved in many hereditary and sporadic human cancers, it is likely that some of these new mutators are equally relevant in cancer etiology.
siRNAs can function as miRNAs
Authors: Doench John G. , Petersen Christian P. , Sharp Phillip A.
Published: February 2003

With the discovery of RNA interference (RNAi) and related phenomena, new regulatory roles attributed to RNA continue to emerge. Here we show, in mammalian tissue culture, that a short interfering RNA (siRNA) can repress expression of a target mRNA with partially complementary binding sites in its 3′ UTR, much like the demonstrated function of endogenously encoded microRNAs (miRNAs). The mechanism for this repression is cooperative, distinct from the catalytic mechanism of mRNA cleavage by siRNAs. The use of siRNAs to study translational repression holds promise for dissecting the sequence and structural determinants and general mechanism of gene repression by miRNAs.
Leisure counselling in stress management
Authors: Juniper Dean
Published: February 2003

Leisure counselling is a fresh and, as yet, relatively underdeveloped, therapeutic approach to a range of emotional stressors, with work‐stress prominent amongst them. Having identified a triad of approach strategies: distraction, anticipation and confrontation, this study seeks to root them theoretically and practically within cognitive‐behavioural, psychodynamic, role‐adaptive and humanistic research findings.
Web‐based technology in support of construction supply chain networks
Authors: Mohamed Sherif
Published: February 2003

Supply chain networks are generally associated with inter‐organisational communications, leading to reduction of time delays in services and information flows. Recognising the importance of communication, this paper deals with the management of information across a network of organisations that are involved in the design and construction process. The paper presents an overview of problems associated with the process of managing construction project information and explores the key role Web‐based technology systems can play in making this process more effective. The paper also reports on the utilisation of such a system on a number of construction projects. It discusses the efficiency gained in the traditional process of architectural drawings transmittal, and reports on a questionnaire survey targeting system users to gain some insight into their perception of its usefulness, performance and role in improving communications amongst the entire project team.
Case study method for new product development in engineer‐to‐order organizations
Authors: Rahman Abdul Rahim Abd , Shariff Nabi Baksh Mohd
Published: February 2003

The case study method has been widely used as a research instrument for data collection to build theory. Reports on the use of case study method for new product development (NPD) in an engineer‐to‐order (ETO) organization. Discusses previous work on NPD in the literature in order to determine the knowledge gap that exists. Discovers that NPD work in an ETO organization is lacking despite its importance. Proposes a case study method as a tool to bridge this gap. Explains and justifies the reasons for choosing the case study method. Also describes case study design with the case study protocol. Then discusses the execution of the case study, method of analysis and the limitations of case study research. The findings will assist researchers who are interested in pursuing future research work in this area.
A study of logistics infomediary in air cargo tracking
Authors: Li Sheng‐Tun , Shue Li‐Yen
Published: February 2003

In e‐commerce, the infomediary is rapidly becoming an important business model on the Web. A low cost Web‐based infomediary for the air cargo industry can help integrate Air Cargo service providers and their customers, and thus improve the productivity of the logistics chain. Customers can access flight information of cargo carriers through the infomediary in a much more simplified way, thus management can better plan the subsequent operations. Proposes a three‐tier paradigm for developing an air cargo logistics infomediary. This paradigm integrates emerging technologies of the next‐generation Web‐based systems to address the three issues for the development. A prototype system was developed to demonstrate its capability in accepting requests from general browsers, retrieving data from different platforms, and presenting data in a consistent and personalized format.
Quality of service middleware
Authors: Adis Warren
Published: February 2003

Quality of service (QoS) middleware is a core technology that will drive the next paradigm in distributed computing. It underlies how computer researchers are addressing the technical demands caused by the exponential growth of Internet activity, the demand for intensive computing in terms of multimedia and distributed applications, and the unpredictability of constantly changing Internet traffic patterns. CORBA represents a class of middleware that has incorporated many QoS features.
Business rules as the basis of an organization’s information systems
Authors: Steinke Gerhard , Nickolette Colleen
Published: February 2003

Business rules are statements that aim to influence or guide behavior and information in the organization. They are the business policies, the business practices, and business definitions that should be well known and treated as a valuable asset to the organization. They are in essence how the actual business is run. Yet so often these business rules are implicit, assumed in the development of information systems in an organization. They have been buried in code, lived in the business experts’ heads and sporadically been documented in system manuals. In this paper we examine the value of business rules, compare the thinking of business rule experts and provide guidelines on how to derive and store an organization’s business rules.
How consumers choose a financial institution: decision‐making criteria and heuristics
Authors: Lee Jinkook , Marlowe Julia
Published: February 2003

Using both qualitative and quantitative approaches, how consumers choose a financial institution for their checking accounts is investigated in this study. It was found that, although most consumers value convenience as one of the most important decision‐making criteria, their definitions of convenience vary across consumers. How different consumers use different decision‐making criteria and heuristics is reported, and the implications for financial service marketers are drawn from the findings.
Characteristics of marketing organisation in the New Zealand financial services sector
Authors: Ashill Nicholas J. , Davies Kevin M. , Thompson Ian W.
Published: February 2003

During the past 15 years, a body of research has explored the implementation of the marketing concept in terms of the integration of marketing functions under the control of a Chief Marketing Executive (CME), and the position of the CME within the organisation. Relatively little attention has been focused on the organisation of the marketing function within professional services industries. We report a cross‐sectional study examining the characteristics of the marketing function and responsibilities of the CME in a major New Zealand professional services sector, financial services. Our findings suggest a high level of formal organisation structure for marketing within the New Zealand financial services industry. However, while the CME continues to be central to the organisation of the marketing function, there remains considerable variation in the corporate positioning of the marketing function and responsibilities of the CME within this professional services industry.
E‐banking and the SME/bank relationship in Northern Ireland
Authors: Ibbotson Patrick , Moran Lucia
Published: February 2003

Internal and external forces continue to impact on the financial service sector, making it ever more difficult for traditional banks both to retain their existing small to medium‐sized enterprises (SME) client base, and to acquire new business clients. The traditionally poor relationship between banks and their small corporate clients has been well documented throughout the years; however, the increased use of electronic banking channels by SME banking customers threatens to change the very nature of that relationship. This paper examines the current nature of the relationship between SMEs and their banks in Northern Ireland and investigates the level of usage of and satisfaction with electronic banking channels in this region. Empirical findings from a research study that included one focus group with members of the Federation of Small Business (FSB) (Northern Ireland members only), interviews with local managers from three traditional banking providers, and a survey of 250 SMEs (Northern Ireland members of FSB) are presented.
Application and development of electronic books in an e‐Gutenberg age
Authors: Chen Ya‐ning
Published: February 2003

Since Gutenberg invented printing in the fifteenth century, the book has become one of the most important information carriers for knowledge distribution, academic research, cultural heritage, and preservation. With advancements in technology both of electronic publishing and universal distribution and access on the Internet, the electronic book is supposed to become another revolution for information dissemination. This paper examines electronic books by giving a review of their historical development, definition and scope, characteristics and constraints, typology, related issues for library services, and user preferences. Consequently, this paper finds that electronic books only bring several evolutionary changes to the current operations of publishing and distribution in comparison with traditional books. The electronic book is just as much a consequence of the application of innovative information technologies as Gutenberg’s were for paper books. A revolutionary change is still required for the electronic book to become ubiquitous.
Managing text digitisation
Authors: Chapman Stephen
Published: February 2003

Good project plans include technical specifications, plans of work, budgets and schedules that are consistent with project goals. Text digitisation presents many variables and many choices, so there is no one‐size‐fits‐all solution to recommend. This article presents a simple‐to‐use questionnaire as a tool for project managers to translate their vision of text digitisation into a series of functional requirements optimised for their collections and users. These requirements can then be used to develop specifications, draft workflows, and select appropriate staff, services and equipment.
Using a Web OPAC to deliver digital collections
Authors: Mathias Eileen C.
Published: February 2003

The Ewell Sale Stewart Library of the Academy of Natural Sciences has just completed a major digital imaging project. This article describes the project, options that were considered for Web delivery of images and text, and reasons for choosing Innovative Interfaces, Inc.’s image management function. The article includes a description of the data entry process as well as a review of the Millennium Media management product, which will be available through Innovative later this year. Evolving image metadata standards are also discussed.
Recent history and development of environmental information systems and databases in Germany
Authors: Page Bernd , Voigt Kristina
Published: February 2003

The topic of environmental protection has always been of great concern in Germany, the establishment of environmental data sources started in the 1970s. The development of environmental information system technology in Germany is outlined and two examples are given: the Environmental Planning and Information System (UMPLIS) and the Integrated Public Environmental Information System (UIS) Baden‐Wuerttemberg. Relevant German environmental data sources are discussed, such as Environmental Literature Database (ULIDAT), Environmental Research Projects Database (UFORDAT), and Environmental Law Databases (URDB), as well as the chemical databases which comprise environmental information – the BEILSTEIN database and the Landolt‐Boernstein database. The Information System for Environmental Chemicals with its four metadatabases – Metadatabase of Literature on Environmental Chemicals (DALI), Metadatabase of Online Databases for Environmental Chemicals (DADB), Metadatabase of CD‐ROMs for Environmental Chemicals (DACD), and the Metadatabase of Internet Resources (DAIN).
Experimentally Tractable, Pseudo-elastic Constitutive Law for Biomembranes: I. Theory
Authors: Criscione John C. , Sacks Michael S. , Hunter William C.
Published: February 2003

Although visco-elastic in general, the stress-strain relation of biomembranes is one-to-one or pseudo-elastic when being loaded after preconditioning. This pseudo-elastic relation is hypoelastic (i.e., it is not hyperelastic), yet much of the stress response can be characterized by a scalar function Ω that represents the work done (per unit reference volume) on the specimen during loading. (Since a pseudo-strain-energy function W is optimized to fit the test data and not the work done, Ω is not equal to W in general.) The remaining part tR of the stress response does no work during loading. With biaxial testing, Ω can be definitively determined from data. Moreover, for tests with the stretch directions coaxial to the axes of anisotropy, tR can be accurately characterized by a scalar function ω that depends on the strain. This paper is part 1 of 2 with “I. Theory” and “II. Application.”
A New Automated Method for the Quantification of Mitral Regurgitant Volume and Dynamic Regurgitant Orifice Area based on a Normalized Centerline Velocity Distribution using Color M-mode and Continuous Wave Doppler Imaging
Authors: Deserranno Dimitri , Greenberg Neil L. , Thomas James D. , Garcia Mario J.
Published: February 2003

Previous echocardiographic techniques for quantifying valvular regurgitation (PISA) are limited by factors including uncertainties in orifice location and hemispheric convergence assumption. Using computational fluid dynamics simulations, we developed a new model for the estimation of orifice diameter and regurgitant volume without the aforementioned assumptions of the PISA technique. Using experimental data obtained from the in vitro flow model we successfully validated our new model. The model output (y) and reference (x) values were in close agreement (y=0.95x+0.38,r=0.96,error=1.68±7.54% for the orifice diameter and y=1.18x−4.72,r=0.93,error=6.48±16.81% for the regurgitant volume).
Adjustment of Muscle Mechanics Model Parameters to Simulate Dynamic Contractions in Older Adults
Authors: Thelen Darryl G.
Published: February 2003

The generation of muscle-actuated simulations that accurately represent the movement of old adults requires a model that accounts for changes in muscle properties that occur with aging. An objective of this study was to adjust the parameters of Hill-type musculo-tendon models to reflect nominal age-related changes in muscle mechanics that have been reported in the literature. A second objective was to determine whether using the parametric adjustments resulted in simulated dynamic ankle torque behavior similar to that seen in healthy old adults. The primary parameter adjustment involved decreasing maximum isometric muscle forces to account for the loss of muscle mass and specific strength with age. A review of the literature suggested the need for other modest adjustments that account for prolonged muscular deactivation, a reduction in maximum contraction velocity, greater passive muscle stiffness and increased normalized force capacity during lengthening contractions. With age-related changes incorporated, a musculo-tendon model was used to simulate isometric and isokinetic contractions of ankle plantarflexor and dorsiflexor muscles. The model predicted that ankle plantarflexion power output during 120 deg/s shortening contractions would be over 40% lower in old adults compared to healthy young adults. These power losses with age exceed the 30% loss in isometric strength assumed in the model but are comparable to 39–44% reductions in ankle power outputs measured in healthy old adults of approximately 70 years of age. Thus, accounting for age-related changes in muscle properties, other than decreased maximum isometric force, may be particularly important when simulating movements that require substantial power development.
Experimental Verification of the Roles of Intrinsic Matrix Viscoelasticity and Tension-Compression Nonlinearity in the Biphasic Response of Cartilage
Authors: Huang Chun-Yuh , Soltz Michael A. , Kopacz Monika , Mow Van C. , Ateshian Gerard A.
Published: February 2003

A biphasic-CLE-QLV model proposed in our recent study [2001, J. Biomech. Eng., 123, pp. 410–417] extended the biphasic theory of Mow et al. [1980, J. Biomech. Eng., 102, pp. 73–84] to include both tension-compression nonlinearity and intrinsic viscoelasticity of the cartilage solid matrix by incorporating it with the conewise linear elasticity (CLE) model [1995, J. Elasticity, 37, pp. 1–38] and the quasi-linear viscoelasticity (QLV) model [Biomechanics: Its foundations and objectives, Prentice Hall, Englewood Cliffs, 1972]. This model demonstrates that a simultaneous prediction of compression and tension experiments of articular cartilage, under stress-relaxation and dynamic loading, can be achieved when properly taking into account both flow-dependent and flow-independent viscoelastic effects, as well as tension-compression nonlinearity. The objective of this study is to directly test this biphasic-CLE-QLV model against experimental data from unconfined compression stress-relaxation tests at slow and fast strain rates as well as dynamic loading. Twelve full-thickness cartilage cylindrical plugs were harvested from six bovine glenohumeral joints and multiple confined and unconfined compression stress-relaxation tests were performed on each specimen. The material properties of specimens were determined by curve-fitting the experimental results from the confined and unconfined compression stress relaxation tests. The findings of this study demonstrate that the biphasic-CLE-QLV model is able to describe the strain-rate-dependent mechanical behaviors of articular cartilage in unconfined compression as attested by good agreements between experimental and theoretical curvefits (r2=0.966±0.032 for testing at slow strain rate; r2=0.998±0.002 for testing at fast strain rate) and predictions of the dynamic response r2=0.91±0.06. This experimental study also provides supporting evidence for the hypothesis that both tension-compression nonlinearity and intrinsic viscoelasticity of the solid matrix of cartilage are necessary for modeling the transient and equilibrium responses of this tissue in tension and compression. Furthermore, the biphasic-CLE-QLV model can produce better predictions of the dynamic modulus of cartilage in unconfined dynamic compression than the biphasic-CLE and biphasic poroviscoelastic models, indicating that intrinsic viscoelasticity and tension-compression nonlinearity of articular cartilage may play important roles in the load-support mechanism of cartilage under physiologic loading.
The Micromechanical Environment of Intervertebral Disc Cells Determined by a Finite Deformation, Anisotropic, and Biphasic Finite Element Model
Authors: Baer Anthony E. , Laursen Tod A. , Guilak Farshid , Setton Lori A.
Published: February 2003

Cellular response to mechanical loading varies between the anatomic zones of the intervertebral disc. This difference may be related to differences in the structure and mechanics of both cells and extracellular matrix, which are expected to cause differences in the physical stimuli (such as pressure, stress, and strain) in the cellular micromechanical environment. In this study, a finite element model was developed that was capable of describing the cell micromechanical environment in the intervertebral disc. The model was capable of describing a number of important mechanical phenomena: flow-dependent viscoelasticity using the biphasic theory for soft tissues; finite deformation effects using a hyperelastic constitutive law for the solid phase; and material anisotropy by including a fiber-reinforced continuum law in the hyperelastic strain energy function. To construct accurate finite element meshes, the in situ geometry of IVD cells were measured experimentally using laser scanning confocal microscopy and three-dimensional reconstruction techniques. The model predicted that the cellular micromechanical environment varies dramatically between the anatomic zones, with larger cellular strains predicted in the anisotropic anulus fibrosus and transition zone compared to the isotropic nucleus pulposus. These results suggest that deformation related stimuli may dominate for anulus fibrosus and transition zone cells, while hydrostatic pressurization may dominate in the nucleus pulposus. Furthermore, the model predicted that micromechanical environment is strongly influenced by cell geometry, suggesting that the geometry of IVD cells in situ may be an adaptation to reduce cellular strains during tissue loading.
A 3D Biomechanical Model of the Hand for Power Grip
Authors: Sancho-Bru Joaquı´n L. , Pe´rez-Gonza´lez A. , Vergara M. , Giurintano D. J.
Published: February 2003

A three-dimensional scalable biomechanical model of the four fingers of the hand to evaluate power grip is proposed. The model has been validated by means of reproducing an experiment in which the subjects exerted the maximal voluntary grasping force over cylinders of different diameters. The model is used to simulate the cylinder grip for two hand sizes and for five different handle diameters. The reduction of the muscle forces using different handle diameters has been studied. The model can be applied to the design and evaluation of handles for power grip and to the study of power grasp for normal and abnormal hands.
Micromechanically Based Poroelastic Modeling of Fluid Flow in Haversian Bone
Authors: Swan C. C. , Lakes R. S. , Brand R. A. , Stewart K. J.
Published: February 2003

To explore the hypothesis that load-induced fluid flow in bone is a mechano-transduction mechanism in bone adaptation, unit cell micro-mechanical techniques are used to relate the microstructure of Haversian cortical bone to its effective poroelastic properties. Computational poroelastic models are then applied to compute in vitro Haversian fluid flows in a prismatic specimen of cortical bone during harmonic bending excitations over the frequency range of 100 to 106Hz. At each frequency considered, the steady state harmonic response of the poroelastic bone specimen is computed using complex frequency-domain finite element analysis. At the higher frequencies considered, the breakdown of Poisueille flow in Haversian canals is modeled by introduction of a complex fluid viscosity. Peak bone fluid pressures are found to increase linearly with loading frequency in proportion to peak bone stress up to frequencies of approximately 10 kHz. Haversian fluid shear stresses are found to increase linearly with excitation frequency and loading magnitude up until the breakdown of Poisueille flow. Tan δ values associated with the energy dissipated by load-induced fluid flow are also compared with values measured experimentally in a concurrent broadband spectral analysis of bone. The computational models indicate that fluid shear stresses and fluid pressures in the Haversian system could, under physiologically realistic loading, easily reach the level of a few Pascals, which have been shown in other works to elicit cell responses in vitro.
Experimentally Tractable, Pseudo-elastic Constitutive Law for Biomembranes: II. Application
Authors: Criscione John C. , Sacks Michael S. , Hunter William C.
Published: February 2003

This is the second paper of a 2 part series. In the first, a theoretical framework is developed that provides 3 enhancements for the constitutive theory of biomembranes. 1) Covariance amongst response terms is minimized, 2) the pseudo-strain-energy potential is redefined so as to be measurable, and 3) the stress response is decomposed into 2 parts—a hyperelastic part plus a hypoelastic-stress-residual. This paper illustrates the experimental advantages of this novel constitutive theory via analysis of biaxial test data obtained from chemically treated bovine pericardium.
The Extent and Distribution of Cell Death and Matrix Damage in Impacted Chondral Explants Varies with the Presence of Underlying Bone
Authors: Krueger J. A. , Thisse P. , Ewers B. J. , Dvoracek-Driksna D. , Orth M. W. , Haut R. C.
Published: February 2003

Excessive mechanical loading can lead to matrix damage and chondrocyte death in articular cartilage. Previous studies on chondral and osteochondral explants have not clearly distinguished to what extent the degree and the distribution of cell death are dependent on the presence of an underlying layer of bone. The current study hypothesized that the presence of underlying bone would decrease the amount of matrix damage and cell death. Chondral and osteochondral explants were loaded to 30 MPa at a high rate of loading (∼600 MPa/s) or at a low rate of loading (30 MPa/s). After 24 hours in culture, matrix damage was assessed by the total length and average depth of surface fissures. The explants were also sectioned and stained for cell viability in the various layers of the cartilage. More matrix damage was documented in chondral than osteochondral explants for each rate of loading experiment. The total amount of cell death was also less in osteochondral explants than chondral explants. The presence of underlying bone significantly reduced the extent of cell death in all zones in low rate of loading tests. The percentage of cell death was also reduced in the intermediate zone and deep zones of the explant by the presence of the underlying bone for a high rate of loading. This study indicated that the presence of underlying bone significantly limited the degree of matrix damage and cell death, and also affected the distribution of dead cells through the explant thickness. These data may have relevance to the applicability of experimental data from chondral explants to the in situ condition.
Tendon to Bone Healing: Differences in Biomechanical, Structural, and Compositional Properties Due to a Range of Activity Levels
Authors: Thomopoulos S. , Williams G. R. , Soslowsky L. J.
Published: February 2003

Little knowledge exists about the healing process of the tendon to bone insertion, and hence little can be done to improve tissue healing. The goal of this study is to describe the healing of the supraspinatus tendon to its bony insertion under a variety of loading conditions. Tendons were surgically detached and repaired in rats. Rat shoulders were then immobilized, allowed cage activity, or exercised. Shoulders that were immobilized demonstrated superior structural (significantly higher collagen orientation), compositional (expression of extracellular matrix genes similar to the uninjured insertion), and quasilinear viscoelastic properties (A=0.30±0.10 MPa vs. 0.16±0.08 MPa, B=17.4±2.9 vs. 15.1±0.9, and τ2=344±161s vs. 233±40 s) compared to those that were exercised, contrary to expectations. With this knowledge of the healing response, treatment modalities for rotator cuff tears can be developed.