bluuebunny/crossref_metadata_2025_split huggingface dataset:
Data realities in plural contexts: Appraisal of a definition [of social informatics]
Authors: Cole Fletcher 
Published: October 2007

AbstractThe meaning of “context” within the definition of social informatics (SI) is explored. The most general context of interest is formed by the relationship between the broad categories of the “technological” and the “social”, as they are manifest in information and communication technologies (ICTs). Within and between these broad categories there are numerous distinct but inter‐related contexts. Contextual complexity at a more detailed level is illustrated through close examination of the data‐related references in a textual description of geographic information systems (GIS). A six‐category taxonomy is used to highlight the complex cross‐referencing between inter‐related vocabularies that reflects the multiple contextual realities involved. They reveal themselves as open to multiple and continuing interpretation within different contexts at different levels of conceptualisation.Practical implications include suggestions that current generalist approaches to systems design may be too removed from the specifics of the task at hand, and that information professionals in their education and training need to be exposed to a wide range of perspectives, reflecting the various human contexts in which their technical expertise is likely to be deployed. What is desirable is a sophisticated appreciation of the many contexts in which ICTs function.
A semiotic view of information: Semiotics as a foundation of LIS research in information behavior
Authors: Huang Sheng‐Cheng 
Published: October 2007

AbstractTraditional information behavior studies in library and information science (LIS) research have focused on primarily two trends: one is to provide physical access to material objects and the other is to direct users to certain thoughts and ideas. Both focuses are two sides of the same problem that LIS researchers have worked to address: how to provide a better system or service to accommodate people's need for information. Among the domains of users, material objects, and meaningful ideas, applying the concept of information as sign with semiotics not only joins these two trends in the analysis of the pragmatic‐syntactic relationship and the pragmatic‐semantic relationship, but it also gives an additional focus on the syntactic‐semantic relationship. It is this additional focus that helps LIS professionals/researchers understand an individual's states of knowing and ways of obtaining knowledge through physical and mental interactions with informative objects. The author conducts a review of information studies, the epistemological concerns and pragmatic traditions in LIS, and semiotics in an attempt to seek a holistic principle that will incorporate both the traditional trends of LIS research and provide an additional awareness in assisting users to make connections between material objects and ideas in information behavior studies. By applying a semiotic view of information and the concept of information as sign, LIS researchers of information behavior will find semiotics a useful epistemological framework.
Specialists and synthesists in a question answering community
Authors: Gazan Rich 
Published: October 2007

AbstractThe most sustainable online communities are those that allow and encourage their users to have a voice in how the community evolves. The proliferation of online communities with collaborative filtering mechanisms, where user feedback is aggregated to shape future interactions, makes it necessary to understand why participants in online communities value the content they do. Building on the concepts of users as specialists and synthesists developed in previous research, this study examines Answerbag, an online question answering community where users rate one another's answers to provide collaborative filtering. In this environment, specialists are operationalized as those who claim expertise in a given topic and answer questions without referencing other sources, and synthesists as those who include one or more references to external sources in their answers. The results of the study suggest that within the Answerbag community as a whole, the answers of synthesists tended to be rated more highly than those of specialists, though answers provided by specialists were rated more highly within certain categories. The consequences of differences in the perceived value of information provided by specialists and synthesists are examined, and avenues for future research are discussed.
Intranet users' information‐seeking behaviour: An analysis of longitudinal search log data
Authors: Stenmark Dick , Jadaan Taline 
Published: October 2007

AbstractToday's knowledge workers rely increasingly on information to get their job done, and the availability of search engines to locate relevant information is thus essential. Understanding how users interact with search engines is a prerequisite for the successful design of useful systems and a body of knowledge has in recent years begun to compile. However, all previous studies have focused on the public web, not acknowledging the fact that much business‐related information seeking occur on corporate internal networks. In this exploratory study, we have collected and analysed intranet search engine log files from three different years – 2000, 2002, and 2004 – enabling us to detect shifting trends in intranet search behaviour. Comparing our data to what has been reported from the public web we conclude that intranet searchers are both similar to and different from searchers on the public web. In sum, it appears that intranet users are more extreme in their behaviour and that qualitative studies are needed to understand the motives and rationales governing their actions.
An Evaluation Model for the National Consortium of Institutional Repositories of Korean Universities
Authors: Kim Hyun Hee , Kim Yong Ho 
Published: October 2007

AbstractThis study, funded by KERIS (The Korean Education and Research Information Service) aims at building an evaluation model for diagnosing and solving problems of the “dCollection” consortium, composed of institutional repositories at more than 40 universities. The evaluation model, as tools not only for a member library's self‐evaluation of its own system but also for assessment of the dCollection systems as a whole, is set up in two steps: First, based upon literature review from digital library evaluation and institutional repositories, and case studies on university repositories, the conceptual framework was composed of four categories: content; system and network; uses, users and submitters; and management and policy. And, second, the evaluation framework was modified through three methods, such as a Delphi method, an expert forum and a simulation test, leading to the evaluation model with 4 categories and 34 indicators.
Carcinogenesis in reflux disease—In search for bile‐specific effects
Authors: Fein Martin , Peters Jeffrey H. , DeMeester Tom R. 
Published: October 2007

AbstractBile reflux may play a key role for esophageal carcinogenesis in reflux disease. In search for bile‐specific effects, the animal model of esophageal cancer was applied in a mutagenesis assay. Big Blue® transgenic mice were operated with microsurgical techniques. Seven had total gastrectomy with esophagojejunostomy creating esophageal reflux of bile and five had a sham operation. After 24 weeks, the mutation frequency (MF) was measured through standard Big Blue mutagenesis assay in the esophageal mucosa and the duodenum as control. Esophageal reflux resulted in esophagitis in the distal esophagus. The MF in esophageal mucosa was 1.6 times higher in animals with reflux than in sham‐operated animals; it was identical in the duodenum. In conclusion, the mutagenic potential of bile reflux has been confirmed. However, mechanisms of carcinogenesis in the esophageal cancer model other than chronic inflammation could not be identified because of the only moderately increased MF. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Human prostate cancer cells express neuroendocrine cell markers PGP 9.5 and chromogranin A
Authors: Leiblich Aaron , Cross Simon S. , Catto James W.F. , Pesce Giancarlo , Hamdy Freddie C. , Rehman Ishtiaq 
Published: October 2007

AbstractBACKGROUNDA proportion of men with prostate cancer will progress to develop metastatic disease involving the lymph‐nodes and bone. To identify novel candidates associated with metastatic progression, we compared the proteomic profiles of LNCaP (lymph‐node metastatic, androgen‐dependant) and PC‐3 (bone metastatic, androgen‐independent), human prostate cancer cells.METHODSTwo‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE), followed by electrospray ionisation tandem mass spectrometry (ESI‐MS/MS), was used to identify differentially expressed proteins. Western blotting was used to validate the identity of any candidates. Immunohistochemistry was used to assess tissue expression.RESULTS2D‐PAGE followed by ESI‐MS/MS analyses identified the expression of glutathione S‐transferase‐pi (GST‐pi) and protein gene product 9.5 (PGP 9.5) in PC‐3 cells, but absent expression in LNCaP cells. PGP 9.5 expression in PC‐3 cells was confirmed by Western blotting, in addition to expression in DU145 cells. Analysis of cell conditioned media showed that PGP 9.5 was secreted. Sequencing of the PGP 9.5 gene promoter region in bisulfite modified DNA, suggested that the regulation of expression involves promoter hypermethylation. RT‐PCR analysis for Chromogranin A (ChA) mRNA (a marker of neuroendocrine cells), showed expression in PC‐3 and DU145 cells but was undetectable in LNCaP cells. Immunohistochemistry localised PGP 9.5 expression exclusively within neuroendocrine cells and nerve fibres.CONCLUSIONSOur unexpected finding that the neuroendocrine cell markers PGP 9.5 and ChA are expressed by PC‐3 and DU145 cells, suggests that these cells may have been derived from metastatic adenocarcinomas which had undergone neuroendocrine differentiation or alternatively the expression occurred ectopically as a result of cell culture. Prostate 67: 1761–1769, 2007. © 2007 Wiley‐Liss, Inc.
High expression of PSM‐E correlated with tumor grade in prostate cancer: A new alternatively spliced variant of prostate‐specific membrane antigen
Authors: Cao Kai‐Yuan , Mao Xiao‐Peng , Wang Dao‐Hu , Xu Lin , Yuan Guang‐Qing , Dai Shu‐Qin , Zheng Bo‐Jian , Qiu Shao‐Peng 
Published: October 2007

AbstractBACKGROUNDProstate‐specific membrane antigen (PSMA) overexpressed in prostate cancer (PCa) has been targeted for therapy and diagnosis of PCa. In the current study, PSMA cDNA was cloned from PCa tissue by RT‐PCR. After sequencing, a new spliced variant of PSMA (PSM‐E) was discovered and its specificity in PCa was evaluated.METHODSPSM‐E and PSMA mRNA were measured in LNCaP, PC‐3 and prostate or nonprostatic malignancies. Following transfection of PC‐3 with PSM‐E cDNA in the pcDNA3.0 vector, PSM‐E expression was measured by immunofluorescence and Western‐blot. PSM‐E and PSMA mRNA levels were quantified by a real‐time PCR assay in normal prostate (n = 7), benign prostatic hyperplasia (BPH) (n = 22) and PCa (n = 41). The correlation between their levels and tumor grade was analyzed.RESULTSPSM‐E cDNA is identical to PSMA except for a 97‐nucleotide region and a 93‐nucleotide region. PSM‐E and PSMA mRNA were detected in PCa and LNCaP, not in PC‐3; PSMA could be detected in some nonprostatic tumors whereas PSM‐E not. The expression of PSM‐E protein was detected in transfected cells. Significant difference of PSM‐E mRNA levels was observed among normal prostate, BPH and PCa (P < 0.001), and PSM‐E levels increased with increasing Gleason score (r = 0.514,P < 0.001). PSMA mRNA levels were higher in BPH and PCa than in normal prostate (P < 0.001), but no difference between BPH and PCa, no significant correlation was observed between PSMA levels and Gleason score (r = 0.229,P = 0.057).CONCLUSIONSPSM‐E may be a potential prognostic indicator for PCa progression and may be a new target antigen for therapy of PCa. Prostate 67: 1791–1800, 2007. © 2007 Wiley‐Liss, Inc.
Theoretical study on the local structure and the spin‐Hamiltonian parameters for Ni2+ ions at Nb sites in LiNbO3 crystal
Authors: Wei Qun , Xu Qi‐Ming , Yang Zi‐Yuan , Zhang Dong‐Yun , Zhang Jian‐Guo 
Published: October 2007

AbstractThe relations between the spin‐Hamiltonian (SH) parameters and crystal structure of LiNbO3:Ni2+ crystal have been established using the SH theory. On this basis, the SH parameters of LiNbO3:Ni2+ crystal have been calculated. The calculated results are in good agreement with experimental data, and this shows that the model adopted is reasonable. Also, the contributions to SH parameters from spin triplets and spin singlets are discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative Structure–Retention Relationship Study of Benzodiazepines Using Adaptive Neuro Fuzzy Inference System as Feature Selection Method
Authors: Jalali‐Heravi Mehdi , Kyani Anahita , Afsari‐Mamaghani Sepideh , Ghadiri‐Bidhendi Atieh 
Published: October 2007

AbstractA Quantitative Structure–Retention Relationship (QSRR) study of 32 benzodiazepines is performed in this work. Two feature selection methods of Adaptive Neuro Fuzzy Inference System (ANFIS) and a stepwise regression approach adopted for the Multiple Linear Regressions (MLR) were used to predict the Liquid Chromatography‐Mass Spectrometry (LC‐MS) Retention Time (RT) of these compounds on a Xterra MS C‐18 stationary phase. ANFIS and MLR methods were used as variable selection tools and a neural network was employed for predicting the RTs. Three descriptors of 3D‐MoRSE‐signal 06/weighted by atomic polarizabilities (Mor06p), Radial Distribution Function‐1.0/weighted by atomic van der Waals volumes (RDF010v), and number of functional groups of RCoN<and >NCN (N‐072) reveal the importance of dispersion interactions between benzodiazepines and C‐18 stationary phases and also electrostatic and hydrogen bond interactions of these compounds with the polar mobile phase. The superiority of 3‐4‐1 ANFIS‐Artificial Neural Networks (ANN) model over MLR‐ANN with a linear feature selection method was illustrated by Leave‐Multiple‐Out (LMO) cross‐validation method. Values of R2L6O=0.771 and RMSEL6O=4.792 for ANFIS‐ANN model should be compared with the values of R2L6O=0.632 and RMSEL6O=6.481 for the MLR‐ANN model. LMO‐CV and Y‐randomization results indicate the robustness and predictive ability of the generated model of ANFIS‐ANN and show the ability of ANFIS in selecting the features for phenomena with nonlinear characteristics. Sequential Zeroing of Weights (SZW) as a sensitivity analysis method showed the importance of dispersion interaction in the retention mechanism of benzodiazepines in LC method.
Generalized electronic diabatic approach to structural similarity in two‐dimensional potential energy surfaces of various topologies
Authors: Arteca Gustavo A. , Rank Jean Pierre , Tapia O. 
Published: October 2007

AbstractActive site properties in some proteins can be affected by conformational fluctuations of neighbor residues, even when the latter are not involved directly in the binding process. A local environment thus appears to alter the relevant potential energy surface and its reaction paths. Here, some aspects of this phenomenon are simulated within a generalized electronic diabatic (GED) scheme to study the geometry and structural similarity for a class of two‐dimensional (2D) energy surfaces. The electronic quantum state is a linear superposition of diabatic basis functions, each of which is taken to represent a single (pure) electronic state for the isolated material system. Here, we describe a model reaction of isomerization by shifts in amplitudes for three diabatic species (reactant, product, and an open‐shell transition state) coupled in an external field. The “effective” 2D energy surface in the field is characterized in terms of critical points, and the amplitudes along the main reaction paths. A new feature is the introduction of a phase diagram where all possible potential‐energy‐surface topologies (consistent with three‐state systems in two linear coordinates) are matched with actual model parameters. By varying the coupling strengths between diabatic states, we classify regions of this phase diagram in terms of electronic and structural similarities; some regions comprise models whose reaction paths have geometries that belong to the catchment region of the reactant, yet are electronically akin to the diabatic transition state or product. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
The symmetry group of nonrigid tetramethylsilane
Authors: Reza Darafsheh Mohammad , Reza Ashrafi Ali , Darafsheh Arash 
Published: October 2007

AbstractUsing nonrigid group theory, it is shown that the full nonrigid (f‐NRG) group of tetramethylsilane is isomorphic to the group C3 S4 of order 1944, where “” denotes the wreath product of groups, and C3 and S4 are the cyclic group of order three and the symmetric group of order four, respectively. This group has 51 conjugacy classes and irreducible representations. Then the character table of tetramethylsilane is derived for the first time. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Substituent effects on O–H and S–H bond dissociation enthalpies of disubstituted phenols and thiophenols
Authors: dos Santos Daniel J. V. A. , Newton Ana S. , Bernardino Raul , Guedes Rita C. 
Published: October 2007

AbstractThe O–H and S–H homolytic bond dissociation enthalpies of a set of disubstituted phenols and thiophenols (NH2, OH, CH3, Cl, CF3, and NO2) have been computed by a density functional theory procedure with the 6‐311++G(d,p) basis set. A very good agreement between our results and available experimental ones is observed. The effect of substituents on structure, charges and BDEs are investigated and their correlation with Hammett parameters is studied. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Theoretical electronic structure of the molecule ScBr
Authors: Korek M. , Hamdan A. 
Published: October 2007

AbstractThe potential energy curves have been investigated for the 23 lowest electronic states in the 2s+1Λ± representation of the molecule ScBr via CASSCF and MRCI (single and double excitations with Davidson correction) calculations. Seventeen electronic states have been studied theoretically for the first time. The harmonic frequency ωe, the internuclear distance re, and the electronic energy with respect to the ground state Te have been calculated. By using the canonical functions approach, the eigenvalues Ev, the rotational constant Bv, and the abscissas of the turning points (Rmin, Rmax) have been calculated for electronic states up to the vibrational level v = 32. The comparison of these values to the theoretical and experimental results available in the literature shows a good agreement. © 2007 Wiley Periodicalsm Inc. Int J Quantum Chem, 2008
Analytical optimization of exponent values in protonic and deuteronic Gaussian‐type functions by elimination of translational and rotational motions from multi‐component molecular orbital scheme
Authors: Ishimoto Takayoshi , Tachikawa Masanori , Nagashima Umpei 
Published: October 2007

AbstractTo optimize the exponent values in protonic and deuteronic Gaussian‐type functions (GTF) by the elimination of translational and rotational motions, we have proposed the new scheme of an analytical gradient formula with respect to the exponent values in the multi‐component molecular orbital scheme, which can take into account the quantum effects of protons and deuterons, under the Hartree‐Fock level of theory. Numerical assessment of H2 and D2 molecules confirms that there is a clear difference between distributions of protonic and deuteronic orbitals following the elimination of translational and rotational motions. In particular, the d‐type GTF in the protonic orbital drastically improves the total energy. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Charge transfer stabilization of an excess electron on a molecular surface
Authors: Jalbout Abraham F. , de Leon Aned 
Published: October 2007

AbstractIn a developed molecular surface model (Jalbout and Adamowicz, Mol Phys, 2006, 19, 3101), we suggested a series of cyclohexane and cyclooctane systems with a hydrogen‐bonded network of OH groups on one side of the surface and hydrogen atoms on the opposite side. The OH groups in this work increased the dipole moment of the complexes in order to form stable dipole bound anions. In this report we consider the dipole‐bound and solvated anions between a set of hypothetical molecular surfaces and NH3BF3. The resulting complexes are stable with respect to vertical electron detachment. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
A relationship between atomic correlation energy and Tsallis entropy
Authors: Grassi A. 
Published: October 2007

AbstractA new relationship between electron correlation energy and Tsallis entropy is presented. This relationship is a generalization of previous equations which correlate the atomic correlation energy and the Shannon entropy. The results, relatively to the atoms with atomic number 2 < Z < 29, put in evidence the crucial role of the p‐parameter in terms of representation of the long‐range interaction contribution in the correlation energy. Moreover, the p‐values, which reproduce the experimental values of the correlation energy, indicate that the atomic wave functions are more localized with respect to those calculated in the limit of p → 1. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Screening for 2‐quinolinone‐derived selective androgen receptor agonists in doping control analysis
Authors: Thevis Mario , Kohler Maxie , Maurer Joachim , Schlörer Nils , Kamber Matthias , Schänzer Wilhelm 
Published: October 2007

AbstractSelective androgen receptor modulators (SARMs) represent a class of emerging drugs with high potential for misuse in sports, and therefore members of this group are banned as anabolic agents by the World Anti‐Doping Agency. Preventive approaches to restrict their use include early implementation of target analytes into doping control screening assays and evaluation of the mass spectrometric behavior of these drugs to allow their unequivocal identification as well as the characterization of structurally related compounds and metabolic products. Four model SARMs with the 6‐alkylamino‐2‐quinolinone structure, including the advanced drug candidate LGD‐2226, were synthesized. Fragmentation pathways after positive electrospray ionization and collision‐induced dissociation were studied using an LTQ Orbitrap mass analyzer, and diagnostic product ions and common dissociation pathways were employed to establish a screening procedure targeting intact quinolinone‐based SARMs as well as putative metabolic products such as dealkylated analogues. Therefore, features of a triple quadrupole mass analyzer such as multiple reaction monitoring and precursor ion scanning were utilized. Sample preparation based on commonly employed liquid‐liquid extraction and subsequent liquid chromatographic/tandem mass spectrometric measurement allowed for detection limits of 0.01–0.2 ng/mL, and intra‐ and interday precisions between 3.2 and 8.5% and between 6.3 and 16.6%, respectively. Recoveries varied from 81 to 98%, and tests for ion suppression or enhancement effects were negative for all analytes. Copyright © 2007 John Wiley & Sons, Ltd.