bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and bonding in binuclear metal carbonyls from the analysis of domain averaged Fermi holes. I. Fe2(CO)9and Co2(CO)8
Authors: Ponec Robert , Lendvay György , Chaves Joaquin 
Published: January 2008

AbstractThe nature of the bonding in the above carbonyls was studied using the analysis of domain averaged Fermi holes (DAFH). The results straightforwardly confirm the conclusions of earlier theoretical studies in which the existence of direct metal–metal bond, anticipated for the above carbonyls on the basis of 18‐electron rule, was questioned. In addition to indicating the lack of direct metal–metal bond, the DAFH analysis also allowed to characterize the nature of the electron pairs involved in the bonding of the bridging ligands. The analysis has shown that because the number of available electron pairs is not sufficient for the formation of ordinary localized 2c‐2e bonds between terminal M(CO)3fragments and the bridging ligands, the bonding in both carbonyls exhibits typical features of electron deficiency and one bonding electron pair is effectively involved in multicenter 3c‐2e bonding. Because of the symmetry of the complexes the bridging ligands are not distinguishable and all M‐C‐M bridges have a partial 3c‐2e nature via resonance of the localized structures. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2008
How stable is a collagen triple helix? An ab initio study on various collagen and β‐sheet forming sequences
Authors: Pálfi Villő K. , Perczel András 
Published: January 2008

AbstractCollagen forms the well characterized triple helical secondary structure, stabilized by interchain H‐bonds. Here we have investigated the stability of fully optimized collagen triple helices and β‐pleated sheets by using first principles (ab initio and DFT) calculations so as to determine the secondary structure preference depending on the amino acid composition. Models composed of a total of 18 amino acid residues were studied at six different amino acid compositions: (i) L‐alanine only, (ii) glycine only, (iii) L‐alanines and glycine, (iv) L‐alanines and D‐alanine, (v) L‐prolines with glycine, (vi) L‐proline, L‐hydroxyproline, and glycine. The last two, v and vi, were designed to mimic the core part of collagen. Furthermore, ii, iii, and iv model the binding and/or recognition sites of collagen. Finally, i models the G→A replacement, rare in collagen. All calculated structures show great resemblance to those determined by X‐ray crystallography. Calculated triple helix formation affinities correlate well with experimentally determined stabilities derived from melting point (Tm) data of different collagen models. The stabilization energy of a collagen triple helical structure over that of a β‐pleated sheet is 2.1 kcal mol−1 per triplet for the [(‐Pro‐Hyp‐Gly‐)2]3 collagen peptide. This changes to 4.8 kcal mol−1 per triplet of destabilization energy for the [(‐Ala‐Ala‐Gly‐)2]3 sequence, known to be disfavored in collagen. The present study proves that by using first principles methods for calculating stabilities of supramolecular complexes, such as collagen and β‐pleated sheets, one can obtain stability data in full agreement with experimental observations, which envisage the applicability of QM in molecular design. © 2008 Wiley Periodicals, Inc.J Comput Chem, 2008
Sonographic diagnosis of spontaneous intramural small bowel hematoma in a case of warfarin overdose
Authors: Hou Sheng‐Wen , Chen Chien‐Chih , Chen Kuo‐Chih , Ko Shih‐Yu , Wong Chung‐Shun , Chong Chee‐Fah 
Published: January 2008

AbstractA 38‐year‐old man who had been treated with warfarin since mitral valve replacement 10 years earlier presented with acute onset of epigastralgia and melena. Coagulation tests were abnormal with a prolonged prothrombin time of >60 seconds and a prolonged activated partial thromboplastin time of >120 seconds. Abdominal sonographic examination revealed duodenal intramural hematoma that was confirmed on CT. Warfarin therapy was stopped and the patient was treated conservatively with vitamin K and fresh frozen plasma. Recovery was uneventful, and the patient was re‐warfarinized 2 weeks later. Duodenal hematoma can be readily diagnosed with bedside sonography. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008.
The origins of the psychological ‘interior’—Evidence from imperial roman literary practices and related issues
Authors: Mahon Ciarán Mc 
Published: January 2008

AbstractThe pervasiveness in psychological literature of the assumption that mental events and psychology in general occur within the person—henceforth the psychological ‘interior’— is introduced and the received view of its historical origin is presented. This account is challenged and classical historical source material from the period 100 to 400 CE is interpreted in relation to factors of literary practice and related issues (mode of reading, authority and format of text, mode of writing, and author's motivation). It is concluded that the ‘interior’ that emerges in the reflexive discourse of Imperial Rome develops in tandem with changes in literary practices and that there is consequently substantial evidence for positing an intimate relationship between these practices, subjective experience, and reflexive discourse. © 2008Wiley Periodicals, Inc.
Synthesis of the perdeuterated cellulose solvents N‐methylmorpholine N‐oxide (NMMO‐d11) and N,N‐dimethylacetamide (DMAc‐d9)
Authors: Adelwöhrer Christian , Yoneda Yuko , Nakatsubo Fumiaki , Rosenau Thomas 
Published: January 2008

AbstractThe synthesis of the perdeuterated cellulose solvents NMMO‐d11 (9) and N,N‐dimethylacetamide‐d9 (14) is described. NMMO‐d11 was obtained according to a five‐step approach from non‐labeled diglycolic acid (1) via diethylene glycole‐d8 (4) and its bis‐tosylate (5), which underwent cyclization with benzylamine to N‐benzylmorpholine (6). The removal of the benzyl protecting group, methylation and N‐oxidation completed the synthesis. DMAc‐d9 (14) was obtained from deuterated acetic acid (10) and dimethylamine–carbon dioxide complex (17) with acidic alumina as the catalyst according to a solvent‐free gas–solid reaction. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of [14C]‐, [13C4]‐, and [13C4, 15N2]‐ 5‐amino‐4‐iodopyrimidine
Authors: Latli Bachir , Jones Paul‐James , Krishnamurthy Dhileepkumar , Senanayake Chris H. 
Published: January 2008

Abstract5‐Amino‐4‐iodopyrimidine labeled with either carbon‐14 or with the stable isotopes carbon‐13 and nitrogen‐15 was prepared starting from commercially available labeled diethylmalonate and formamide. This compound is a useful intermediate for carbon–nitrogen and carbon–carbon bond formations. Copyright © 2008 John Wiley & Sons, Ltd
Synthesis of deuterium‐labeled zaleplon‐d5 as an internal standard
Authors: Shaikh Ajam C. , Chen Chinpiao 
Published: January 2008

AbstractZaleplon is licensed for the short‐term treatment of insomnia. Excessive usage causes side effects; hence, the drug is controlled. Identifying zaleplon in a drug abuser requires an isotope‐labeled internal standard. This work presents a synthesis of stable isotope‐labeled internal standard for zaleplon, zaleplon‐d5, by a five‐step synthetic sequence. Copyright © 2008 John Wiley & Sons, Ltd.
Work‐life benefits and positive organizational behavior: is there a connection?
Authors: Muse Lori , Harris Stanley G. , Giles William F. , Feild Hubert S. 
Published: January 2008

AbstractFocusing on the employee well‐being component of positive organizational behavior (POB), this study explores the relationship between organization provided benefit programs and POB. Specifically, we ask the question: are employees' use and perceived value of a work‐life benefit package associated with their positive attitudes and behaviors in the workplace? Grounded in social exchange theory and the norm of reciprocity, we develop and estimate a model identifying differential relationships of benefit use and perceived benefit value with employee attitudinal and performance outcomes. Employing the multigroup method, the hypothesized model was fit to the data of two dissimilar organizations. Results support our hypothesis that providing work‐life benefits employees use and/or value is part of a positive exchange between the employee and employer. This exchange is positively related to employees' feelings of perceived organizational support and affective commitment to the organization and reciprocation in the form of higher levels of task and contextual performance behaviors. Results also revealed that employees' perceptions of benefit program value play a critical role regardless of actual program use in influencing attitudes and behavior. Our findings emphasize the importance of valuing employees and investing in their well‐being inside as well as outside the workplace. Copyright © 2008 John Wiley & Sons, Ltd.
Linking service employees' emotional competence to customer satisfaction: a multilevel approach
Authors: Giardini Angelo , Frese Michael 
Published: January 2008

AbstractThis study investigates the role of the positive organizational behavior (POB) concept of emotional competence for the effective management of participants' affect in service encounters and customers' assessments about the encounter. We developed and tested a two‐level model in which service employees' emotional competence is related to both service employees' and customers' state positive affect. Customers' positive affect, in turn, is related to customers' specific and general evaluations of the service rendered. A total of 394 service encounters involving 53 financial consultants of a bank were assessed. Data were analyzed by a combination of path analysis and hierarchical linear modeling (HLM), and the results support large parts of the model. More specifically, employees' emotional competence was related to customer evaluations through their own positive affective state during the encounter as well as through a direct link to the customer evaluations of the encounter. Copyright © 2008 John Wiley & Sons, Ltd.
The comparison of solid phase microextraction‐GC and static headspace‐GC for determination of solvent residues in vegetable oils
Authors: Ligor Magdalena , Buszewski Bogusław 
Published: January 2008

AbstractThe objective of these investigations has been the determination of volatile organic compounds including residue solvents present in vegetable oil samples. Some olive oil, rape oil, sunflower oil, soy‐bean oil, pumpkin oil, grape oil, rice oil as well as hazel‐nut oil samples were analysed. Among residue solvents the following compounds have been mentioned: acetone, n‐hexane, benzene, and toluene. Some experiments for the solid phase microextraction (SPME)–GC‐flame ionisation detection (FID) were performed to examine extraction conditions such as fiber exposure time, temperature of extraction, and temperature of desorption. Various SPME fibers such as polydimethylsiloxane, Carboxen/polydimethylsiloxane and polydimethylsiloxane/divinylbenzene coatings were used for the isolation of tested compounds from vegetable oil samples. After optimisation of SPME, real vegetable oil samples were examined using SPME‐GC/MS. Based on preliminary experiments the qualitative and quantitative analyses for the determination of acetone, n‐hexane, benzene and toluene were performed by SPME‐GC‐FID and static head‐space (SHS)‐GC‐FID methods. The regression coefficients for calibration curves for the examined compounds were R2 ⪈ 0.992. This shows that the used method is linear in the examined concentration range (0.005–0.119 mg/kg for SPME‐GC‐FID and 0.003–0.728 mg/kg for SHS‐GC‐FID). Chemical properties of analysed vegetable oils have been characterised by chemometric procedure (cluster analysis).
Diagnosis of Helicobacter pylori infection with the 13C‐urea breath test by means of GC‐MS analysis
Authors: Jordaan Maraliese , Laurens Johannes B. 
Published: January 2008

AbstractThe diagnosis of Helicobacter pylori (H. pylori) infection by GC‐MS detection of the 13CO2 enrichment in 13C‐urea breath test (13C‐UBT) samples is reported. This study aimed to optimize the 13C‐UBT with regards to the diagnostic cut‐off value, sampling time, and frequency. The H. pylori status of 103 dyspeptic patients was obtained by histological examination, the rapid urease test as well as with the GC‐MS 13C‐UBT. Analytical and diagnostic accuracies were determined by comparison of the GC‐MS 13C‐UBT results with that of the analytical and diagnostic gold standards, namely GC‐isotope ratio MS (IRMS) and histology. The 13CO2 enrichment values obtained with GC‐MS analysis, correlated favorably (r2 = 0.993) with those obtained by GC‐IRMS analysis. When compared to histology, the GC‐MS 13C‐UBT had a diagnostic sensitivity of 92% and a specificity of 93%. The positive predictive value (PPV), negative predictive value (NPV), and accuracy were 95, 89, and 92%, respectively. It was concluded that SIM GC‐MS is capable of analyzing nonradioactive 13C‐UBT samples, with a precision and accuracy sufficient to distinguish between H. pylori positive and negative patients.
Spatial alignment of the mouse blastocyst axis across the first cleavage plane is caused by mechanical constraint rather than developmental bias among blastomeres
Authors: Alarcón Vernadeth B. , Marikawa Yusuke 
Published: January 2008

AbstractThe embryonic–abembryonic (Em–Ab) axis of the mouse blastocyst has been found in several studies to align orthogonal to the first cleavage plane, raising the possibility that a developmental prepattern already exists at the two‐cell stage. However, it is also possible that such alignment is not due to any developmental disparity between the two‐cell stage blastomeres, but rather is caused by an extrinsic mechanical constraint that is conferred by an irregular shape of the zona pellucida (ZP). Here, we conducted a series of experiments to distinguish between these possibilities. We showed that the shape of the ZP at the two‐cell stage varied among embryos, ranging from near spherical to ellipsoidal, and that the ZP shape did not change until the blastocyst stage. In those embryos with an ellipsoidal ZP, the Em–Ab axis tended to lie orthogonal to the first cleavage plane, while in those embryos with a near spherical ZP, there was no such relationship. The clonal boundary between the descendants of the two‐cell stage blastomeres tended to lie orthogonal to the Em–Ab axis when the rotation of the embryo within the ZP was experimentally prevented, while the control embryos did not exhibit such tendency. These results support the possibility that an apparent correlation between the first cleavage plane and the blastocyst axis can be generated by the mechanical constraint from the ZP but not by a developmental prepattern. Moreover, recent reports indicate that the vegetal blastomere of the four‐cell stage embryo that had undergone a specific type of second cleavages is destined to contribute to the abembryonic side of the blastocyst. However, our present study shows that in spite of such specific second cleavages, the vegetal blastomere did not preferentially give rise to the abembryonic side. This result implicates that the lineage of the four‐cell stage blastomere is not restricted even when embryos undergo a specific type of second cleavages. Mol. Reprod. Dev. 75: 1143–1153, 2008. © 2008 Wiley‐Liss, Inc.
Constitutive description of interface behavior including cyclic loading and particle breakage within the framework of critical state soil mechanics
Authors: Liu Huabei , Ling Hoe I. 
Published: January 2008

AbstractThe cyclic behavior of soil–structure interface can be very important in dynamic problems. The cyclic behavior of soil–structure interface may be nonlinear, which includes hysteresis, hardening, degradation, and particle breakage. The breakage of granular soil particles during shearing of granular soil–structure interface is associated with cyclic degradation and can be critical to the dynamic behavior of soil–structure system. The critical state soil mechanics concept formerly used to simulate the nonlinear monotonic behavior of granular soil–structure interface was modified and extended to describe the cyclic behavior, especially soil‐particle breakage and degradation during cyclic shearing. Soil‐particle breakage was assumed to relate to the energy consumption during cyclic shearing and the critical state line of the soil–structure interface was assumed to translate with the consumption of shearing energy during cyclic shearing as the threshold value is attained. The model was formulated in the framework of generalized plasticity and is capable of describing the salient features of granular soil–structure interface under cyclic loading. Most of the model parameters have straightforward physical meanings and are calibrated using monotonic or cyclic interface test results. The proposed model was calibrated and validated against published test results. The dependency of interface behavior on stress path and cyclic degradation can be successfully described by the proposed model. Copyright © 2008 John Wiley & Sons, Ltd.
Uniform convergence of the multigrid V‐cycle on graded meshes for corner singularities
Authors: Brannick James J. , Li Hengguang , Zikatanov Ludmil T. 
Published: January 2008

AbstractThis paper analyzes a multigrid (MG) V‐cycle scheme for solving the discretized 2D Poisson equation with corner singularities. Using weighted Sobolev spaces Kma(Ω) and a space decomposition based on elliptic projections, we prove that the MG V‐cycle with standard smoothers (Richardson, weighted Jacobi, Gauss–Seidel, etc.) and piecewise linear interpolation converges uniformly for the linear systems obtained by finite element discretization of the Poisson equation on graded meshes. In addition, we provide numerical experiments to demonstrate the optimality of the proposed approach. Copyright © 2008 John Wiley & Sons, Ltd.
Metaphors in qualitative research: Shedding light or casting shadows?
Authors: Carpenter Jacque 
Published: January 2008

AbstractThe use of metaphors in qualitative research provides an opportunity to examine phenomena from a unique and creative perspective. Metaphors can be used to provide structure to the data; to understand a familiar process in a new light; to identify situation‐specific interventions; and to evoke emotion. Misuse of metaphors may detract from the intended research message. Mixing metaphors, failing to follow through with metaphors, and using metaphors that do not fit the data can misrepresent the data. The choice to use metaphors should not become a self‐serving attempt at creativity that supersedes subject and substance. At their best, metaphors illuminate the meanings of experiences; at their worst, metaphors distort or obscure the essences of them. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:274–282, 2008
Histopathological and immunohistochemical characterization of canine prostate cancer
Authors: Lai Chen‐Li , van den Ham René , van Leenders Geert , van der Lugt Jaco , Mol Jan A. , Teske Erik 
Published: January 2008

AbstractBackgroundIn this study we try to identify the origin of canine prostate cancer (cPC) by classifying the tumors histological subtypes and relate these subtypes to their combined expressional characteristics of several tissue specific and differentiation markers.MethodscPCs were examined histomorphologically and by immunohistochemical detection of the cytokeratin markers CK14, HMWCK, CK5, CK18, and CK7, and of the markers UPIII, PSA and PSMA.ResultsHistopathologically, six growth patterns could be differentiated. The most frequent patterns were solid, cribriform and micropapillary growth patterns, while sarcomatoid, small acinar/ductal, and tubulo‐papillary growth patterns were less frequent present. Solid growth patterns were significantly (P = 0.027) more often seen in castrated dogs. Immunohistochemically, about half of the cPC cases showed expression of PSA (8/20) and PSMA (10/20); 85% and 60% of the cPC expressed UPIII (17/20) and CK7 (12/20), while 13 and 12 cPC expressed CK5 and CK14, respectively; all cPC expressed CK18. CK14 was significantly more often and UPIII less frequent expressed in the solid growth patterns than in the micropapillary and cribriform patterns, respectively.ConclusionsCanine prostate cancer appear to be more aggressive and of a less differentiated type than most common human prostate cancers. Comparing the expression patterns of the markers in cPC to those in normal canine prostate tissue, cPC most likely originates from the collecting ducts rather than from the peripheral acini. Given also the fact that canine prostate cancer is unresponsive to androgen withdrawal therapy, canine prostate cancer mostly resembles human, androgen refractory, poorly differentiated prostate cancer. Prostate 68: 477–488, 2008. © 2008 Wiley‐Liss, Inc.
Obsidian hydration dating by SIMS‐SS: Surface suitability criteria from atomic force microscopy
Authors: Liritzis I. , Bonini M. , Laskaris N. 
Published: January 2008

AbstractObsidian artefacts used by prehistoric people could be dated by the SIMS‐SS method. However, the method contains some limitations regarding the degree of smoothness of the surface. The presence of wells, cracks, pits, crystals and/or crests induce errors in the dating. Here, we briefly introduce the SIMS‐SS method and provide first images of the atomic force microscopy (AFM) of obsidian surfaces and discuss the impact of AFM results on the SIMS‐SS dating. The presented dating is straightforward for flat regular surfaces and problematic for irregular surfaces. Copyright © 2008 John Wiley & Sons, Ltd.
Capture-avoiding substitution as a nominal algebra
Authors: Gabbay Murdoch J. , Mathijssen Aad 
Published: January 2008

Abstract
Substitution is fundamental to the theory of logic and computation. Is substitution something that we define on syntax on a case-by-case basis, or can we turn the idea of substitution into a mathematical object? We give axioms for substitution and prove them sound and complete with respect to a canonical model. As corollaries we obtain a useful conservativity result, and prove that equality-up-to-substitution is a decidable relation on terms. These results involve subtle use of techniques both from rewriting and algebra. A special feature of our method is the use of nominal techniques. These give us access to a stronger assertion language, which includes so-called ‘freshness’ or ‘capture-avoidance’ conditions. This means that the sense in which we axiomatise substitution (and prove soundness and completeness) is particularly strong, while remaining quite general.