bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of diphenyl ether herbicides on porphyrin accumulation by cultured hepatocytes
Authors: Jacobs Judith M. , Sinclair Peter R. , Gorman Nadia , Jacobs Nicholas J. , Sinclair Jacqueline F. , Bement William J. , Walton Heidi
Published: October 2006

Several diphenyl ether herbicides, such as acifluorfen methyl, have been previously shown to cause large accumulations of the heme and chlorophyll precursor, protoporphyrin, in plants. Lightinduced herbicidal damage is mediated by the photoactive porphyrin. Here we investigate whether diphenyl ether herbicides can affect porphyrin synthesis in rat and chick hepatocytes. In rat hepatocyte cultures, protoporphyrin, as well as coproporphyrin, accumulated after treatment with acifluorfen or acifluorfen methyl. Combination of acifluorfen methyl with an esterase inhibitor to prevent the conversion of acifluorfen methyl to acifluorfen resulted in a greater accumulation of porphyrins than caused by acifluorfen methyl or acifluorfen alone. In vitro enzyme studies of hepatic mitochondria isolated from rat and chick embryos demonstrated that protopor‐phyrinogen oxidase, the penultimate enzyme of heme biosynthesis, was inhibited by low concentrations of acifluorfen, nitrofen, or acifluorfen methyl with the latter being the most potent inhibitor. These findings indicate that diphenyl ether treatment can cause protoporphyrin accumulation in rat hepatocyte cultures and suggest that this accumulation was associated with the inhibition of protoporphyrinogen oxidase. In cultured chick embryo hepatocytes, treatment with acifluorfen methyl plus an esterase inhibitor caused massive accumulation of uroporphyrin rather than protoporphyrin or coproporphyrin. Specific isozymes of cytochrome P450 were also induced in chick embryo hepatocytes. These effects were not observed in the absence of an esterase inhibitor. These results suggest that diphenyl ether herbicides can cause uroporphyrin accumulation similar to that induced by other cytochrome P450‐inducing chemicals such as polyhalogenated aromatic hydrocarbons in the chick hepatocyte system.
Stimulation of the active transport of serotonin into mouse platelets by the sulfhydryl oxidizing agent diamide
Authors: Bosin Talmage R. , Kasper Gregory C.
Published: October 2006

The purpose of this study was to determine the effects of diamide, a reversible sulfhydryl oxidizing agent, on the transport of serotonin (5‐HT) by mouse platelets. Diamide produced a concentration‐dependent (10–200 μM) stimulation of 5‐HT transport that was rapid and sustained over 0–10 minutes of incubation. When platelets were incubated with diamide (10–200 μM) in the presence of glucose, the content of reduced glutathione was significantly decreased only at a final concentration of 200 μM, while washed platelets incubated with diamide (10–200 μM), in the absence of glucose, had a significant concentration‐dependent decrease in their content of reduced glutathione. Fluoxetine, an inhibitor of the platelet 5‐HT transporter, blocked diamide‐induced stimulation of 5‐HT transport. The kinetics of 5‐HT transport showed that diamide caused a marked increase in the maximal rate of transport (Vmax control = 28.4 ± 1.4 vs. Vmax diamide = 60.9 ± 4.1 pM/108 platelets/4 min) but did not significantly alter the Km values. Ouabain, an inhibitor of platelet Na+‐K+ ATPase, blocked the stimulation by diamide in a concentration‐dependent manner. Dithiothreitol, a disulfide reducing agent, was able to partially reverse the stimulation of platelet 5‐HT transport caused by diamide. This study has shown that diamide can stimulate the active transport of 5‐HT by mouse platelets and suggests a possible role for free sulfhydryl groups in the regulation of this process.
Strand scission in DNA by Gossypol and Cu(II): Role of Cu(I) and oxygen‐free radicals
Authors: Zaidi Rana , Hadi S. M.
Published: October 2006

Gossypol, a polyphenolic binaphthyl dialdehyde found in cotton seeds, is a dietary mutagen and a potential male contraceptive. In the presence of Cu(II), gossypol caused breakage of supercoiled plasmid pBR322 DNA. The products were relaxed circles or a mixture of these and linear molecules. Other metal ions tested [Ni(II), Co(II), Mn(II), and Fe(II)] were ineffective or less effective in the DNA breakage reaction. In the case of gossypol‐Cu(II) mediated cleavage, (Cu(I) was shown to be an essential intermediate by using the Cud) sequestering reagent bathocuproine. By using job plots, it was established that in the absence of DNA, eight Cu(II) ions can be reduced by one gossypol molecule. The involvement of active oxygen species, such as singlet oxygen and H2O2, was established by the inhibition of DNA breakage by catalase and by sodium azide. It was further shown that gossypol is capable of directly producing H2O2.
Heterogeneity of antibodies to metallothionein isomers and development of a simple enzyme‐linked immunosorbent assay
Authors: Chan Hing Man , Pringle Gordon A. , Cherian M. George
Published: October 2006

A competitive enzyme‐linked immunosorbent assay (ELISA) for the measurement of metallothionein (MT) in tissues and body fluids has been developed. The ELISA employs the IgG fraction of a rabbit antiserum to rat liver Cd‐MT‐2 polymer, a biotinylated secondary antibody, and peroxidase conjugated avidin. With a 1:4000 dilution of the immunoglobulins, typical standard curves (logit‐log regression) provide a linear range of 0.1–100 ng for MT‐2 and 10–1000 ng for MT‐1. Fifty percent inhibition is accomplished with 15 ng and 250 ng for MT‐2 and MT‐1, respectively. Rat liver MT‐1 and MT‐2 containing different metals (Ag, Cu, and Zn) inhibited the antibodies as effectively as CdMT. However, the antibodies exhibited greater affinity for both Apo‐MT isoforms. Previously reported discrepancies between results obtained by metal binding assays (e.g., Ag‐hem binding) and radioimmunoassay for MT levels in tissues have been largely resolved. By addition of 1% Tween 20 to samples, the ELISA routinely estimated the total MT in samples of rat, mouse, and human liver and kidney at 88% of the value obtained by the silver‐hem binding assay. Specific antibodies to MT‐2 were purified from our anti‐serum by affinity purification using CH‐Sepharose 4B coupled with rat liver MT‐1. Estimation of MT in samples using purified MT‐2 antibodies provided slightly lower values (72%) for MT in tissues as compared to the Ag‐hem method. The predominant form of MT in tissues of control animals was found to be MT‐2. Therefore, the MT‐2 specific antibodies may be useful for the study of the functions of MT isoforms. Levels of total MT in tissues and biological fluids of rats injected with CdCl2 (0.3 mg Cd/kg) and Cd‐MT (0.3 mg Cd/kg) were estimated by ELISA. The results suggest urinary MT levels may be related to kidney damage.
Specific induction of hepatic cytochrome p4501a‐2 in C57BL/6 and DBA/2 mice treated with 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ)
Authors: Nerurkar Pratibha V. , Anderson Lucy M. , Snyderwine Elizabeth G. , Park Sang Shin , Thorgeirsson Snorri S. , Rice Jerry M.
Published: October 2006

The food mutagen/carcinogen amino‐3‐methylimidazo[4,5‐f]quinoline (IQ) is activated by cytochrome p4501a‐2 via N‐hydrox‐ylation; various P450s may contribute to detoxification via ring hydroxylation. Alterations in P450 levels by IQ treatment might therefore influence its toxicity. To examine the role of Ah locus genotype on the biochemical effects of IQ, C57BL/6 (AhbAhb; p450Ia‐½ inducible) and DBA/2 (AhdAhd, noninducible) mice of both sexes were given IQ at varying doses, with different vehicles and routes of administration. Livers taken after 24 hours were assessed for total cytochrome p450 and activities of ethoxyresorufin‐O‐deethylase (EROD, a p4501a‐l activity, inducible in Ahb mice), meth‐oxyresorufin‐O‐demethylase (MROD, a p4501a‐2 activity), and benzyloxyresorufin‐O‐dealkylase (BzROD, an activity of p4502b). There was little effect on total cytochrome p450, but all three enzyme activities were often induced, a maximum of 2.5‐fold, in both sexes and in DBA/2 as well as C57BL/6 mice. However, Western immunoblot analysis with monoclonal antibodies demonstrated an increase only in p4501a‐2 protein. p4501a‐l remained undetectable. A monoclonal antibody to p4502‐b recognized one protein band in liver mi‐crosomes from males and two bands in female mice of both strains. Amounts of these proteins were not altered by IQ treatment. Thus, IQ specifically, if moderately, induces its activating enzyme, p4501a‐2, in a process that was not clearly related to Ah responsiveness.
Characterization of the acyl‐CoA: Amino acid N‐acyltransferases from primate liver mitochondria
Authors: Kelley Michael , Vessey Donald A.
Published: October 2006

The acyl‐CoA:amino acid N‐acyl‐transferases were partially purified from human liver mitochondria. The aralkyl transferase (ArAlk) had glycine conjugating activity toward the following compounds: benzoyl‐CoA > butyryl‐CoA, salicylyl‐CoA > heptanoyl‐CoA, indoleacetyl‐CoA. Its kinetic properties and responses to salt were very similar to those of bovine ArAlk. Further, its molecular weight was found to be similar to that of the bovine enzyme, in contrast to reports from other laboratories. Thus, it was concluded that the human and bovine ArAlk are not significantly different.

The human arylacetyl transferase (AAc) had glutamine conjugating activity toward phenylacetyl‐CoA, but only 3–5% as much activity toward indoleacetyl‐CoA or 1‐naphtylacetyl‐CoA, respectively. While this was similar to the bovine AAc, the two forms differed in several respects. First, the human liver AAc was insensitive to salts. Second, glycination of phenylacetyl‐CoA by human AAc could only be detected at a high concentration of glycine (50 mM), and the rates were <2% of the rate of glutamination. In contrast, glycine conjugation predominates with bovine AAc. Kinetic analysis of the glutamination of phenylacetyl‐CoA by human AAc revealed a KD for phenylacetyl‐CoA of 14 μM and a Km for glutamine of 120 mM. These values indicate that the human AAc is not more efficient at glutamination than the AAc from bovine liver. An AAc was purified from rhesus monkey liver and found to have similar kinetic constants to the human form. This indicates that nonprimate enzymes do not have a defect in glutamine conjugation. Rather, it is the primate forms that are defective in that they have lost glycine conjugation, not increased the efficiency of glutamine conjugation.
Choline derivatives and sodium fluoride protect acetylcholinesterase against irreversible inhibition and aging by DFP and paraoxon
Authors: Dehlawi Mohamed S. , Eldefrawi Amira T. , Eldefrawi Mohyee E. , Anis Nabil A. , Valdes James J.
Published: October 2006

A light addressable potentiometric sensor was used to measure acetylcholinesterase (AChE) activity in order to evaluate the protective effects of quaternary compounds and NaF against enzyme phosphorylation and aging by two organophosphates. The use of the immobilized AChE made possible the quick removal of reagents (i.e., organophosphate, 2‐pralidoxime, and protectant), thereby permitting accurate determination of AChE activity before and after phosphorylation and aging. Paraoxon was 15‐fold more potent in inhibiting AChE than DFP, while the percent aging following phosphorylation by diiso‐propylfluorophosphate (DFP) was much higher. Sodium fluoride (NaF), the most effective protectant against phosphorylation and aging, and the quaternary ammonium compounds reduced significantly AChE inhibition by DFP and paraoxon, to similar degrees. Even though the percent AChE activity that was lost to aging was reduced by these agents, aging as a percent of phosphorylated AChE was not reduced. Thus, their major effect was in reducing the percent AChE phosphorylation, which consequently resulted in reduction of total aged AChE. The finding that quaternary ammonium compounds protect against phosphorylation is consonant with the proposed presence of the active site of AChE in an aromatic gorge.
The modulating effects of tumor necrosis factor alpha antibody on ricin‐induced oxidative stress in mice
Authors: Muldoon D. F. , Bagchi D. , Hassoun E. A. , Stohs S. J.
Published: October 2006

Previous studies in our laboratory have shown that the protein toxin ricin induces an oxidative stress in mice, resulting in increased urinary excretion of malondialdehyde (MDA), formaldehyde (FA), and acetone (ACON). Other toxicants have been shown to induce oxidative stress by macrophage activation with subsequent release of reactive oxygen species and tumor necrosis factor alpha (TNF‐α). Therefore, the ability of TNF‐α antibody to modulate ricin‐induced urinary carbonyl excretion as well as hepatic lipid peroxidation, glutathione depletion, and DNA single‐strand breaks was assessed. Ricin‐induced urinary MDA, FA, and ACON were reduced significantly in mice receiving antibody (15,000 U/kg) 2 hours before treatment with ricin (5 μ/kg). At 48 hours following ricin treatment, MDA, FA, and ACON concentrations in the urine of TNF antibody‐treated mice decreased 25.7, 53.2, and 64.5%, respectively, relative to ricin‐treated mice receiving no antibody. In addition, anti‐TNF‐α (1500 U/kg) significantly decreased hepatic lipid peroxidation and DNA single‐strand breaks, induced by 5 μg ricin/kg, by 49.3 and 44.2%, respectively. The results suggest that macrophage activation and subsequent release of TNF‐α are involved in ricin toxicity.
Gender differences in hepatic expression of flavin‐containing monooxygenase isoforms (FMO1, FMO3, and FMO5) in Mice
Authors: Falls J. Greg , Blake Bonnie L. , Cao Yan , Levi Patricia E. , Hodgson Ernest
Published: October 2006

Hepatic flavin‐containing monooxygenase (FMO) activity of microsomes from adult CD‐1, Swiss‐Webster, C57BL/6, and DBA/2 mice was found to be significantly higher in females than in males. Based on protein and mRNA levels in CD‐1 mice, FMO forms responsible for the gender difference in FMO activity were FMO1 and FMO3. FMO1 expression was two to three times higher in female mice compared with males; FMO3, however, which was expressed at levels equivalent to FMO1 in female mice, was not detected in males. The expression of FMO5 was approximately equal in both sexes. FMO2 and FMO4 transcripts were not evident in hepatic mRNA from mice. Protein and mRNA levels appear to be coregulated with regard to gender‐selective or gender‐specific expression of FMO1 or FMO3, respectively. FMO5, which demonstrates no gender‐selective expression in mice, may be regulated by different mechanisms. Examination of protein levels among Swiss‐Webster, C57BL/6, and DBA/2 strains revealed a gender‐dependent expression of FMO isozymes identical to the CD‐1 strain.
Some aspects of the role of cytochrome P‐450 isozymes in the n‐oxidative transformation of secondary and tertiary amine compounds
Authors: Hlavica Peter , Lehnerer Michael
Published: October 2006

Indirect evidence of the participation of cytochrome P‐450 (P‐450) in the microsomal N‐oxygenation of secondary and tertiary nitrogen functions is presented by studies employing diagnostic modifiers of the hemoprotein system as well as antibodies directed toward the diverse P‐450 isoforms and NADPH‐cytochrome P‐450 reductase. Experiments with recombinant hemoproteins or P‐450 isozymes directly purified from the tissues of various animal species support the results obtained by the inhibitor assays. Although the intermediacy of aminium radicals is thought to be restrictive to P‐450‐catalyzed N‐oxygenation of secondary and tertiary amine groups bearing accessible hydrogens on the α‐carbon, numerous exceptions to this rule are documented. It is proposed that aminium radicals partition between oxygen rebound and α‐hydrogen abstraction to yield a finite level of N‐oxygenated product in all P‐450‐mediated amine oxidations, the partition ratio depending on the amine structure and particular P‐450 isozyme operative. In some instances, N‐oxygenation appears to proceed by peroxidatic mechanisms. The relative contribution of P‐450 to the N‐oxygenation of secondary and tertiary amines in crude preparations or live animals, where competition with the flavin‐containing monooxygenase (FMO) occurs, seems to be a function of the relative amounts and catalytic capacities of the two enzyme systems. Both parameters are species and tissue dependent. Accordingly, the extent to which P‐450 contributes to total N‐oxidative turnover of the amine substrates varies from minor to major. © 1996 John Wiley & Sons, Inc.
The laterophysic connection and swim bladder of butterflyfishes in the genus Chaetodon (Perciformes: Chaetodontidae)
Authors: Webb Jacqueline F. , Smith W. Leo , Ketten Darlene R.
Published: October 2006

The laterophysic connection (LC) is an association between bilaterally paired, anterior swim bladder extensions (horns) and medial openings in the supracleithral lateral line canals that diagnoses butterflyfishes in the genus Chaetodon. It has been hypothesized that the LC makes the lateral line system sensitive to sound pressure stimuli that are transmitted by the swim bladder horns and converted to fluid flow into the lateral line system via a laterophysic tympanum. The purpose of this study was to define variation in the morphology of the LC, swim bladder and swim bladder horns among 41 Chaetodon species from all 11 Chaetodon subgenera and a species from each of four non‐Chaetodon genera using gross dissection, histological analysis as well as 2D or 3D CT (computed tomographic) imaging of live, anesthetized fishes. Our results demonstrate that the lateral line system appears rather unspecialized with well‐ossified narrow canals in all species examined. Two LC types (direct and indirect), defined by whether or not the paired anterior swim bladder horns are in direct contact with a medial opening in the supracleithral lateral line canal, are found among species examined. Two variants on a direct LC and four variants of an indirect LC are defined by combinations of soft tissue anatomy (horn length [long/short] and width [wide/narrow], number of swim bladder chambers [one/two], and presence/absence of mucoid connective tissue in the medial opening in the supracleithrum). The combination of features defining each LC variant is predicted to have functional consequences for the bioacoustics of the system. These findings are consistent with the recent discovery that Chaetodon produce sounds during social interactions. The data presented here provide the comparative morphological context for the functional analysis of this novel swim bladder‐lateral line connection. J. Morphol., 2006. © 2006 Wiley‐Liss, Inc.
Nanobiomaterial applications in orthopedics
Authors: Christenson Elizabeth M. , Anseth Kristi S. , van den Beucken Jeroen J.J.P. , Chan Casey K. , Ercan Batur , Jansen John A. , Laurencin Cato T. , Li Wan‐Ju , Murugan Ramalingam , Nair Lakshmi S. , Ramakrishna Seeram , Tuan Rocky S. , Webster Thomas J. , Mikos Antonios G.
Published: October 2006

Advancements in nanobiotechnology are revolutionizing our capability to understand biological intricacies and resolve biological and medical problems by developing subtle biomimetic techniques. Nanocomposites and nanostructured materials are believed to play a pivotal role in orthopedic research since bone itself is a typical example of a nanocomposite. This article reviews current strategies using nanobiomaterials to improve current orthopedic materials and examines their applications in bone tissue engineering. Preliminary investigations support the potential of nanobiomaterials in orthopedic applications; however, significant advancements are necessary to achieve clinical use. Overall, current trends in nanobiotechnology foreshadow a bright future through the use of nanobiomaterials in the orthopedic domain. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:11–22, 2007
Communication regimes: A conceptual framework for examining IT and social change in organizations
Authors: Meyer Eric T.
Published: October 2006

This paper defines and extends Kling's concept of a communication regimes by identifying the concept's origins and offering a definition that will allow further research using this framework. The terminology used here originates in political science; in translating these concepts for information science, however, much of the original meaning can be maintained and fruitfully applied. The paper outlines the definition and illustrates it using examples from photojournalism as a communication regime undergoing change. A communication regime is: 1) a loosely coupled social network in which the communication and the work system are highly coupled; 2) a system with a set of implicit or explicit principles, norms, rules, and decision‐making procedures around which actors' expectations converge; 3) a system in which the types of communication are tightly coupled to the production system in which they are embedded; 4) a system with institutions which help to support and to regulate the regime; and 5) a system within which there are conflicts over control, over who enforces standards, over who bears the costs of change and who reaps the benefits of change. This example suggests other areas where a communication regime framework may help understand the relationship between IT and social change.
Cross‐cultural issues in user learning and the design of digital interfaces
Authors: Bilal Dania , Bachir Imad , Caidi Nadia , Komlodi Anita , Dalbello Marija , Mehra Bharat
Published: October 2006

Hall (1976) believes that culture is a selective screen through which we see the world and that the basic differences in the way members from different cultures perceive reality are responsible for the mis‐communications of the most fundamental kind. Hofstede (1997) notes that cultural orientations are deeply embedded in cultures over hundreds and thousands of years and modern media have not dislodged these cultural orientations. Indeed, cultural norms, assumptions, values, and orientations remain crucial for understanding people from various cultures. This understanding extends to designing a variety of information retrieval systems for international access and use, including Web‐based digital libraries. Since the Web is international in nature, Web design should embed ‘cultural attractors” (e.g., colors, metaphors, language cues, navigation controls, and other visual elements) that should create the’ look and feel” to match the cultural expectations of the users of a local culture (Smith, et al., 2004). The speakers will address the various roles culture plays in the design and use of system interfaces, in general, and of digital libraries in particular. They will present analyses from their current research findings on culture and its impact on information seeking, interface design, and digital library development. They will discuss methods of bridging the gap between various cultures through both providing effective user‐centered system design and educating information professionals.
Metadata characteristics as predictors for editor selectivity in a current awareness service
Authors: Krichel Thomas , Bakkalbasi Nisa
Published: October 2006

RePEc is a large digital library for the economics community. “NEP: New Economics Papers” is a current awareness service for recent additions to RePEc. The service is run by volunteer editors. They filter new additions to RePEc into subject‐specific reports. The intended purpose of this current awareness service is to filter papers by subject matter without any judgment of their academic quality. We use binary logistic regression analysis to estimate the probability of a paper being included in any of the subject reports as a function of a range of observable variables. Our analysis suggests that, contrary to their own claims, editors use quality criteria. These include the reputation of the series as well as the reputation of the authors. Our findings suggest that a current awareness service can be used as a first step of a peer‐review process.
Motivations and uses: An evaluation of users' use of a chat reference service
Authors: Luo Lili , Pomerantz Jeffrey
Published: October 2006

This poster presents an evaluation of NCknows, a state‐wide chat reference service in North Carolina, to explore users' motivation for using this service and how they use the information provided to them in real life situations, which reflects the value of the service to them. Users were interviewed by email or telephone two weeks after their chat sessions with NCknows. The findings suggest that most users were motivated by tasks or projects with which they were involved or by some aspect of their personal life. Over sixty percent of users reported they used the information provided to them to fulfill the information needs that motivated them to use the service. Non‐use or partial use cases were also categorized for a better understanding of how the service aided users.
Automatic subject heading assignment for online government publications using a semi‐supervised machine learning approach
Authors: Hu Xiao , Jackson Larry S. , Deng Sai , Zhang Jing
Published: October 2006

As the dramatic expansion of online publications continues, state libraries urgently need effective tools to organize and archive the huge number of government documents published online. Automatic text categorization techniques can be applied to classify documents approximately, given a sufficient number of labeled training examples. However, obtaining training labels is very expensive, requiring a lot of manual labor. We present a real world online government information preservation project (PEP) in the State of Illinois, and a semi‐supervised machine learning approach, an Expectation‐Maximization (EM) algorithm‐based text classifier, which is applied to automatically assign subject headings to documents harvested in the PEP project. The EM classifier makes use of easily obtained unlabeled documents and thus reduces the demand for labeled training examples. This paper describes both the context and the procedure of such an application. Experiment results are reported and other alternative approaches are also discussed.
Knowledge management practices in organizations undergoing fundamental change
Authors: Edgar Bill , Detlor Brian , Mackenzie Maureen , Turnbull Don
Published: October 2006

This session combines individual presentations with a group discussion. The focus of this session and the expertise of this panel bring together the information‐related issues of organizational change, managing knowledge, enabling technology and the role of senior management. This session reflects the interests of SIG‐MGT membership and aligns with the ASIST 2005 theme of “Bringing Research and Practice Together.”
Recent developments in electronic resource management
Authors: Kasprowski Rafal , Anderson Ivy , Weir Barbara , Fons Ted
Published: October 2006

The management of electronic resources relies increasingly on the effective uses of technology and the ability to integrate the processes involved and standardize the ways in which they are performed. Topics of interest in this field include licensing, resource administration, user authentication, resource sharing, and usage data collection. Recently attempts have been made to integrate these functions into single packages (electronic resource management systems), as open‐source and usage‐data standards are being developed. The session on electronic resources management organized by SIG‐LT will provide insight into the challenges of this branch of librarianship and present its recent progresses.
Interrupted cognition in an undergraduate programming course
Authors: Wijekumar Kay , Meidinger Paul
Published: October 2006

Computer and Information Science courses are frequently taught in networked computer laboratories where students have access to advanced development environments, connectivity, communications, and multi‐media capabilities. Advanced connectivity and communications can have positive or negative effects on learning. One cause for concern can be interruptions from emails, cell phones, and instant messages. This paper presents a theoretical foundation for Technology Interrupted Cognitive processes with examples of how learners' cognitive schemas maybe positively or negatively affected by the interruptions specifically from instant messages. The paper also presents findings from a research study to document the frequency and prevalence of instant messaging use by students. Results document the approaches that the students participating in the study use and how their cognitive structures are affected by instant messaging interruptions. Finally the paper also recommends guidelines for reducing the negative effects of interruptions on cognitive processes.
Finding nutrition information on the Web: Coverage vs. authority
Authors: Doran Susan G. , de Ycaza Samuel , Eastman Caroline M. , Jansen Bernard J.
Published: October 2006

The ability of different types of web sites to provide relevant information in response to queries in the area of nutrition is investigated here. Nutrition related queries from users of the Excite search engine were posed to a number of nutrition Web sites in order to assess whether or not topical matches were found. The queries were also submitted to four general‐purpose search engines. Surrogate users were used to assess the actual relevance of topical matches. Matches were retrieved for about 36% of the queries on the nutrition sites; the range for different sites went from a low of 8.6% to a high of 68.6%. For the general search engines, matches were retrieved for about 92% of the queries. Almost all of the topical matches in both cases were judged relevant.
Intellectual structure and subject themes in information systems research: A journal cocitation study
Authors: Marion Linda S. , Wilson Concepcion S. , Davis Mari
Published: October 2006

Information Systems (IS) is a discipline in which research and practice are closely intertwined. IS is also closely related to and overlapping several other disciplines, including Information Science. Thus, IS provides an excellent case for examining the interplay of research and practice in a rapidly changing discipline. We explore the intellectual structure and subject themes in Information Systems (IS) research for 1990 to 1999 through the identification and analysis of the field's core journal literature. A core journal list of 100 titles was created and examined with journal cocitation analysis (JSA). JSA demonstrates that IS is a coherent discipline with research ranging from technology‐oriented software and hardware to the application of IS in business and organizations. Journals are grouped into seven subject clusters: computer science, computer networking, computer engineering, information science, software engineering, human‐computer interaction, and management information systems. Information Science journals occupy a bridging position between technically oriented and application‐focused clusters. ASIST publications, JASIST, ARIST, and PASIS, figure prominently in the Information Science cluster.
An extensible approach to interoperability testing: The use of special diagnostic records in the context of Z39.50 and online library catalogs
Authors: Moen William E. , Taylor Sebastian Hammer and Mike , Yoon Jason Thomale and JungWon
Published: October 2006

Assessing interoperability in the networked information services and applications environment presents difficult challenges due in part to the multi‐level and multi‐faceted aspects of interoperability. Recent research to establish an interoperability testbed in the context of Z39.50 protocol clients and servers and online catalog applications identified threats to interoperability and defined a question space for interoperability testing. This paper reports on follow‐up research to develop an alternative approach for interoperability testing in the context of networked information retrieval that uses specially designed diagnostic records. These records, referred to as radioactive records, enable interoperability assessment at the protocol and semantic levels. This approach appears to offer an extensible method for interoperability testing for other metadata and protocol application environments. The resulting interoperability testbed incorporates additional components to exploit automatic processes for interoperability testing and assessment, thus improving the efficiency of interoperability testing.
Are library and information science journals becoming more internationalized? — A longitudinal study of authors' geographical affiliations in 20 LIS journals from 1981 to 2003
Authors: Sin Sei‐Ching Joanna
Published: October 2006

This paper examines journal publications in the field of library and information science (LIS) to assess the level of internationalization in their publications authorship pattern. The international production and communication of scholarly knowledge is crucial to the growth of a discipline. Recent advancement in communication technology and the rise of globalization have led to the hope of a more balanced flow of scientific knowledge. Nevertheless, scholars also cautioned the possibility of a global digital divide and a widening knowledge gap. This study analyzed the geographical affiliations of authors in 20 international LIS journals to track the longitudinal changes in LIS authorship pattern. Findings suggest an increase in the internationalization of LIS authorships over the years. However, the LIS authorship distribution was still highly uneven in 2003 (Gini coefficient = 0.95). Economic power is still found to be a moderate predictor of publication performance. The findings of this study suggest that, at the moment of the writing, there is still room for the LIS field to be more internationalized. Further research is needed to identify the barriers in international scholarly communication and to explore the implications of such a communication pattern on scientific development and global equality.
Metadata quality and evaluation
Authors: Busch Joseph , Greenberg Jane , Liddy Elizabeth D. , Moen William E. , Zeng Marcia , Subrahmanyam Bhagirathi
Published: October 2006

Good “quality metadata supports the functional requirements of the system it is designed to support” (Guy, Powell, & Day, 2004). Researchers (e.g., Moen, Stewart, and McClure, 1997; Bruce & Hillman, 2004) have identified evaluation criteria and issues surrounding metadata evaluation. This panel further explores metadata quality and evaluation challenges. Specific topics covered include how metadata specialists (library catalogers) utilize available rich content designation for MARC bibliographic records and professional metadata creators—and the identification of evaluation criteria; means for comparing metadata generated by resource authors, automatic metadata generation applications; and two National Science Foundation National Science Digital Library (NSF‐NSDL) projects: a tripartite evaluation involving a metadata quality study, an information retrieval study, and a metadata user study; and a quality assessment of metadata records contributed by members to the NSDL.
Automatic evaluation of credibility on the Web
Authors: Wassmer Marcus , Eastman Caroline M.
Published: October 2006

A system to automatically assess credibility of web sites is described. The system uses information about credentials, advertisements, and web design to produce a credibility measure. The system was tested on several web sites in the medical domain. It selected the same three domains as most credible as did two manual rankings from the Wall Street Journal and a Stanford University research study.
Engagement as process in human‐computer interactions
Authors: O'Brien Heather L. , Toms Elaine G.
Published: October 2006

Recently there has been an increased emphasis on holistic user experiences in human‐computer interactions. Interface design is moving beyond usability, aiming to be aesthetically pleasing, emotionally appealing, and engaging. The term engagement is frequently mentioned in the literature as a goal of interface design, yet the construct remains abstract and ill‐defined. The well‐established frameworks of Flow Theory, Play Theory, and Aesthetic Theory provide a foundation in which to ground engagement and to begin to explore the attributes that must be present in engaging design. We conceptualize engagement as a process rather than a single instance. Our proposed model views engaging interactions as being comprised of three distinct stages: the user must become engaged, sustain the engagement, and eventually disengage from the system. Establishing a solid framework for engagement will enable us to operationally define the term and to develop techniques and instruments for measuring it. Without a rich, theoretical understanding of what constitutes engaging interactions between users and computer interfaces, we cannot ensure that design practices are truly engaging; user's experience with computer‐mediated environments must involve the user cognitively, behaviorally, and affectively.
Geographical representation of library collections in WorldCat: A prototype
Authors: Connaway Lynn Silipigni , Snyder Clifton , Olszewski Lawrence
Published: October 2006

In today's world, people can be inundated by an overwhelming amount of information. Library and information science professionals attempt to provide information systems that are capable of retrieving precise and accurate information. One method for the organization and retrieval of geographically‐based information is to develop a system to visually represent the data. A prototype for an interactive map, the OCLC World Map, was developed to provide a visual tool for the management and representation of geographically‐based library collections and library data. These data are used to provide information for decision‐making in regard to remote storage, collection management and cooperative collection development, preservation, and digitization. The collection data for the map were generated from WorldCat, the OCLC Online Computer Library Center bibliographic database. WorldCat contains approximately 55 million records, and not only serves as an aggregator of bibliographic data, but also identifies a billion holding locations by type of library for library resources. Additional data, gathered from more than thirty other sources, such as library expenditures and number of libraries, are represented on the OCLC WorldMap.
Interoperability strategies for scientific cyberinfrastructure: Research and practice
Authors: Baker Karen S. , Ribes David , Millerand Florence , C. Bowker Geoffrey
Published: October 2006

The development of new infrastructures for research and collaboration are occurring together with changes in expectations for scientific knowledge. New vocabularies and perspectives are developing with social and organizational practices of science changing concurrently but at different rates. Between the new infrastructures and the new perspectives, we are changing both how we know and what it is to know.

A recently initiated three year project supported by the NSF Human Social Dynamics Program (Interoperability Strategies for Scientific Cyberinfrastructure: A Comparative Study) brings together work with three established research collaborations on large‐scale information infrastructures in order to understand through comparative study particular configurations of technologies, communities, and organizations. Despite specific alignments of technical commitment, community involvement and organizational structure, all the projects fall under a common rubric of achieving for data interoperability.
Policy capturing models for multi‐faceted relevance judgments
Authors: Huang Xiaoli , White Ryen W.
Published: October 2006

We applied policy capturing and bootstrapping methods to investigate the relevance judgment process, with a particular focus on understanding how judges summarize an overall relevance judgment from five specific aspects of relevance. Our data come from relevance judgments made in the development of the MALACH (Multilingual Access to Large Spoken ArCHives) Speech Retrieval Test Collection. We developed a linear model for each of four relevance judges by regressing his/her overall judgments on the five specific relevance aspects. According to these models, different judges tended to assign different importance weights to different aspects. One of the linear models was applied to seven new judgment sets and was highly successful at predicting accurate overall judgments for the seven judgment sets.
Metadata as infrastructure: What, where, when and who
Authors: Buckland Michael K. , Larson Ray R.
Published: October 2006

Metadata is ordinarily used to describe documents, but metadata can also constitute a form of infrastructure for access to networked resources. Design and standards issues for building an infrastructure using the four facets: What, Where, When and Who, are presented.
Trouble ahead: Propositional attitudes and metadata
Authors: Renear Allen , Choi Yunseon
Published: October 2006

We argue that the natural pressure to develop increasingly expressive metadata systems will soon present new and very difficult problems to the metadata community. In particular we draw attention to propositional attitudes, which will be important for a wide variety of metadata applications, including representations of trust in ecommerce, and representations of provenance, expert assessments, and social context in the management of cultural objects. However propositional attitudes are extremely difficult to represent in a way that supports automated inferencing. Both the web and the museum informatics community have recognized this problem and stipulate limitations to their systems. But eventually this problem will require more functional resolution. We believe that intentionality‐related problems, like the representation of propositional attitudes will soon be more important to metadata and knowledge representation research than traditional modeling problems, such as the expressiveness vs. efficiency tradeoff.
Users' conceptual structure, search process and useful information types in the retrieved references
Authors: Vakkari Pertti , Serola Sami , Pennanen Mikko
Published: October 2006

This study focuses on the relationship between students' conceptual understanding of their information need, search process and search outcome in terms of useful information types in the references retrieved for their task. The research subjects were 22 undergraduates of psychology preparing a research proposal. They were asked to make searches in the PsycINFO database in the beginning of their proposal preparation. A pre‐ and post‐search interview was conducted and the search logs were recorded. The students assessed the utility of the references retrieved in terms of given information types useful for their task, i.e. using multidimensional relevance assessments. Students' conceptual structure was both directly and indirectly connected to the number of retrieved references via search tactics, providing certain types of information for the task. Different search tactics led to the retrieving of references containing different types of information. It was observed that certain field codes of PsycINFO fitted in part with the useful information types. Signalling more clearly those field codes related to these dimensions of topicality, could help users in articulating their information needs and consequently in improving search results.
Authenticity: New personas for digital media
Authors: Blanchette Jean‐François , Bachimont Bruno , Mak Bonnie , Salaün Jean‐Michel
Published: October 2006

This panel approaches the problem of authenticity as the concept is evolving through technological practices. Most debates surrounding this evolution have proceeded from a naturalized definition of authenticity. This definition is largely founded on the printed word tradition and the principle that faithfulness to the written word is paramount, while stylistic modifications to the form of documents are acceptable.

This naturalized definition can be problematized using two different axes: (1) from textual to non‐textual (e.g., audio‐visual) documents; (2) from paper to electronic media. In the first case, there are no general and stable conventions for distinguishing content from its formal manifestation. In the second case, the only stable measure of authenticity, that of bitwise integrity, (a) is too restrictive to deal with the inevitable logical format migrations that must occur for digital media to remain accessible; and (b) does not measure how the rendering process of the bitstream (e.g., on screen, on paper) conforms to the content of the document.

The papers in this panel will explore how new electronic documentary practices challenge the naturalized definition of authenticity, and chart how concepts of authenticity evolve in conjunction with such practices. The papers will suggest how new rules and conventions for defining authenticity may emerge in given areas of documentary practices — digitized medieval manuscripts, electronic contracts, XML‐encoded documents — or from multidisciplinary research efforts.
Information visualization: From conceptual theory to digital implementation
Authors: Neal Diane , Hastings Samantha K. , Jeong Wooseob , Uzwyshyn Ray
Published: October 2006

Information visualization allows the exploration of large sets of non‐linear paradigms for the organization of a wider spectrum of media elements (i.e. video, visual images, sound, and datasets). Information visualization in the form of 2D and 3D objects and environments has been moving from conceptual theory to digital implementation. The panelists represent different projects that have brought theory into implementation and will share information, demonstrations, and results.
Light and electron microscopic studies of the murine heart after repeated administrations of ciguatoxin or ciguatoxin‐4c
Authors: Terao Kiyoshi , Ito Emiko , Yasumoto Takeshi
Published: October 2006

After repeated ip and oral administrations of ciguatoxin (CTX) and ciguatoxin‐4c (CTX‐4c), one of the derivatives of CTX, to male ICR mice at a dose of 0.1 μg/kg for 15 days, resulted in marked swelling of cardiac cells and endothelial lining cells of blood capillaries in the heart was observed. Single doses caused no discernible pathological changes. Damage to the capillaries was followed by prominent effusion of serum and erythrocytes into the interstitial spaces of the myocardium occurred. Swelling of the endothelial lining cells of capillaries caused narrowing of the lumen and accumulation of blood platelets in capillaries, which resulted in multiple single cell necroses of cardiac muscle cells. Within 1 month after the treatments of these phycotoxins, myocytes and capillaries appeared to be normal. Effusion in the interstitial spaces resulted in formation of bundles of dense collagen, which persisted for 14 months. Diffuse interstitial fibrosis was prominent in septum and ventricles, accompanied by bilateral ventricular hypertrophy. A single dose of 0.7 μg/kg ip resulted in severe acute heart injuries, followed by diffuse myocardial fibrosis. © 1992 Wiley‐Liss, Inc.