bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and GIAO NMR calculations for some new 4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐one derivatives: comparison of theoretical and experimental 1H and 13C chemical shifts
Authors: Yüksek Haydar , Gürsoy Ozlem , Cakmak Ismail , Alkan Muzaffer 
Published: May 2005

AbstractFour novel 3‐alkyl(aryl)‐4‐(4‐methoxycarbonylbenzylidenamino)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones (2) were synthesized by the reactions of 3‐alkyl(aryl)‐4‐amino‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones (1) with methyl 4‐formylbenzoate and characterized by elemental analyses and IR, 1H NMR, 13C NMR and UV spectral data. In addition, isotropic 1H and 13C nuclear magnetic shielding constants of 2 were obtained by the gauge‐including‐atomic‐orbital (GIAO) method at the B3LYP density functional level. The geometry of each compound was optimized using the 6–311G basis set. Copyright © 2005 John Wiley & Sons, Ltd.
On two‐grid convergence estimates
Authors: Falgout Robert D. , Vassilevski Panayot S. , Zikatanov Ludmil T. 
Published: May 2005

AbstractWe derive a new representation for the exact convergence factor of classical two‐level and two‐grid preconditioners. Based on this result, we establish necessary and sufficient conditions for constructing the components of efficient algebraic multigrid (AMG) methods. The relation of the sharp estimate to the classical two‐level hierarchical basis methods is discussed as well. Lastly, as an application, we give an optimal two‐grid convergence proof of a purely algebraic ‘window’‐AMG method. Published in 2005 by John Wiley & Sons, Ltd.
Sulfonated poly(ethylene‐ran‐styrene) ionomers
Authors: Shim Sang‐Yeon , Weiss RA 
Published: May 2005

AbstractIonomers were prepared by partially sulfonating the styrene units of a poly(ethylene‐ran‐styrene) (ES) copolymer. The metal salt derivatives of sulfonated ES had higher Tg, melt viscosity and rubbery modulus than did the parent ES because of the formation of labile, physical crosslinks from intermolecular dipole–dipole associations between metal sulfonate groups. Microphase separation of ion‐rich aggregates with a characteristic size of 3–9 nm also occurred as a result of the strong intermolecular associations. Copyright © 2005 Society of Chemical Industry
Asymmetric penta‐armed poly(ε‐caprolactone)s with short‐chain phosphazene core: synthesis, characterization, and in vitro degradation
Authors: Yuan Weizhong , Song Qing , Zhu Lu , Huang Xiaobin , Zheng Sixun , Tang Xiaozhen 
Published: May 2005

AbstractA novel hydroxyl‐terminated short‐chain penta‐armed phosphazene was prepared. This penta‐armed compound was studied as an initiator for the synthesis of asymmetric penta‐armed poly(ε‐caprolactone)s in the presence of stannous octoate. The effect of molar ratio of monomer to initiator was investigated. Thermal analysis revealed that the penta‐armed poly(ε‐caprolactone)s possessed lower melting point and crystallinity than linear ones. The penta‐armed poly(ε‐caprolactone)s with long chain‐length exhibited higher onset decomposition temperature and maximum decomposition temperature than linear ones owing to the presence of the phosphazene core. The in vitro degradation of linear and penta‐armed PCL was performed in phosphate buffer solution at 37 and 55 °C. Copyright © 2005 Society of Chemical Industry
Dependence of the luminescent properties and chain length of poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] on the formation of cis‐vinylene bonds during Gilch polymerization
Authors: Fan Yang‐Liang , Lin King‐Fu 
Published: May 2005

AbstractThe presence of cis‐vinylene bonds in Gilch‐polymerized poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] is reported. Through fractionation, species with a weight‐average molecular weight of less than 37,000 exhibited an abnormal blueshift of photoluminescence spectra in toluene solutions, and this was attributed to the presence of cis‐vinylene bonds, as verified by NMR spectroscopy. Surprisingly, the fractionated species (∼1 wt %) with a weight‐average molecular weight of 5000 were mostly linked by the cis‐vinylene bonds. The concentration decreased with the molecular weight until a molecular weight of 37,000 was reached; at that point, the polymer chains contained mainly trans‐vinylene bonds. Obviously, the formation of cis‐vinylene bonds strongly inhibited the growth of polymer chains during Gilch polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2520–2526, 2005
Chain‐end modification of living anionic polybutadiene with diphenylethylenes and styrenes
Authors: Donkers Ellen H. D. , Willemse Robin X. E. , Klumperman Bert 
Published: May 2005

AbstractThe first step in the transformation of poly(butadienyl)lithium into a macromolecular atom transfer radical polymerization initiator or reversible addition–fragmentation chain transfer agent is the modification of the anionic chain end into a suitable leaving/reinitiating group. We have investigated three different modification reactions to obtain a styrenic end group at the chain end of poly(butadienyl)lithium. In all cases, we have looked at the influence of a Lewis base on the progress of the reaction. The first modification reaction with α‐methylstyrene leads to partial functionalization and oligomerization. The second reaction with 1,2‐diphenylethylenes, particularly trans‐stilbene, results in monoaddition to the poly(butadienyl)lithium chain ends. Quantitative functionalization is not obtained, possibly because of a hydrogen abstraction reaction, which causes termination. In the third modification reaction, a small polystyrene block is successfully added to the chain ends, as shown by a detailed matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry analysis of the block copolymers. Nearly quantitative block copolymer formation is achieved, with an average styrene block size of four monomer units and a polydispersity index of 1.19 for the polystyrene block. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2536–2545, 2005
High prevalence of gastroesophageal reflux in children after lung transplantation
Authors: Benden Christian , Aurora Paul , Curry Joe , Whitmore Pauline , Priestley Lorraine , Elliott Martin J. 
Published: May 2005

AbstractBronchiolitis obliterans and its clinical correlate bronchiolitis obliterans syndrome (BOS) are a major cause of morbidity and mortality following lung transplantation. Gastroesophageal reflux disease (GERD) may be a contributing factor for the development of BOS. Since 2002, all recipients of lung and heart‐lung transplantation at our institution have been routinely investigated for GERD. In this observational study, we report on the prevalence of GERD in this population, including all pediatric patients undergoing single (SLTx) or double (DLTx) lung transplantation or heart‐lung (HLTx) transplantation from January 2003–May 2004. GERD was assessed 3–6 months after transplantation by 24‐hr pH testing. The fraction time (Ft) with a pH < 4 within a 24‐hr period was recorded. Spirometry data, episodes of confirmed acute rejection, and demographic data were also collected. Ten transplant operations were performed: 4 DLTx, 1 SLTx, and 5 HLTx. Nine patients had cystic fibrosis. One patient had end‐stage pulmonary disease secondary to chronic aspiration pneumonia and postadenovirus lung damage. Of 10 patients tested, 2 had severe GERD (Ft > 20%), 5 had moderate GERD (Ft 10–20%), 2 had mild GERD (Ft 5–10%), and 1 had no GERD. The only patient in this group with no GERD had a Nissen fundoplication pretransplant. All study patients were asymptomatic for GERD. All patients with episodes of rejection had moderate to severe GERD posttransplant. There was no association between severity of GERD and peak spirometry results posttransplant. Moderate to severe GERD is common following lung transplantation in children. © 2005 Wiley‐Liss, Inc.
Optical study of AlGaN/GaN based HEMT structures grown on sapphire and SiC
Authors: Ochalski Tomasz J. , Grzegorczyk Andrzej , Rudzinski Mariusz , Larsen Poul K. , Holtz Per Olof , Bergman Peder , Paskov Plamen P. 
Published: May 2005

AbstractA detailed photoluminescence (PL), time‐resolved photoluminescence (TRPL), and photoreflectance (PR) analysis of AlGaN/GaN heterostructures grown on different substrates: sapphire and silicon carbide (SiC) is presented in this paper. The properties of high electron mobility transistors (HEMTs) based on AlGaN/GaN structures are strongly dependent on the quality of the AlxGa1−xN top layer. We have examined a number of samples, grown on sapphire, in which the thicknesses of the Al0.3Ga0.7N layers vary from 18 to 75 nm. Room temperature PL under pulsed 266 nm excitation allowed for determination of the Al content in the examined thin AlGaN layers. Time‐resolved PL measured at 1.6 K showed huge difference in the emission dynamics for different Al0.3Ga0.7N layer thicknesses. We observed an enormous increase of the emission decay time above the critical thickness of the AlGaN layer. PR spectra (associated with the GaN main layer) measured on AlGaN/GaN systems are discussed in terms of the thickness of the capping layer. The PR modulated by a high power 266 nm pulsed laser measured on a transistor structure exhibited an additional feature placed between signals related to the GaN and AlGaN layers, respectively. Such a transition is possible to monitor only for the structures of the best quality and is accordingly observable only on samples grown on SiC. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Beyond vibrational self‐consistent‐field methods: Benchmark calculations for the fundamental vibrations of ethylene
Authors: Christiansen Ove , Luis Josep M. 
Published: May 2005

AbstractA number of different methods for calculation of vibrational energies are reviewed and tested for calculation of the fundamental vibrational frequencies for ethylene. The methods tested for the description of the vibrational states are vibrational self‐consistent field (VSCF), vibrational configuration interaction (VCI), vibrational Møller–Plesset theory (VMP), and vibrational coupled cluster (VCC). The convergence of the different methods toward the full vibrational configuration interaction (FVCI) result is discussed for a modest‐sized one‐mode basis. For larger one‐mode basis sets results are presented for selected methods. Different representations of the potential energy surface are compared including full and partial quartic force field as well as expansions using up to sixth derivatives of the potential energy surface. Using MP2 electronic structure theory, the electronic structure basis set convergence is tested. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Brief report: The ego identity process questionnaire: Factor structure, reliability, and convergent validity in Dutch‐speaking late adolescents
Authors: Luyckx Koen , Goossens Luc , Beyers Wim , Soenens Bart 
Published: May 2005

AbstractThe reliability and validity of a Dutch version of the Ego Identity Process Questionnaire (EIPQ) were evaluated. In Study 1, the instrument was found to exhibit a clear factor structure and acceptable reliability. Using Confirmatory Factor Analysis, both a model with two process factors (Commitment, Exploration) and a model with four content factors (Ideological Commitment, Ideological Exploration, Interpersonal Commitment, Interpersonal Exploration) evidenced a good fit once direction of wording was taken into account. In Study 2, moderate convergence was observed between Commitment and Exploration, and continuous measures of identity statuses and identity styles. The results of both studies combined indicated that the Dutch version of the EIPQ may be recommended as a research tool with college students.
Chela-height vs. body-weight relationships for North Sea hermit crabs (Paguridae)
Authors: Reiss Henning , Neumann Hermann , Kröncke Ingrid 
Published: May 2005

Abstract
Biomass determination of hermit crabs is difficult without destroying the gastropod shells of the specimens. To minimize the number of animals destroyed in the process of determining this parameter over time, the chela-height vs. body-weight relationship of each of the three hermit-crab species was recorded in different areas of the North Sea. Linear regression was carried out for the species Pagurus bernhardus, P. pubescens, and P. prideauxi, in order to allow calculations of individual biomass on the basis of the chela height of specimens. No spatial differences in the chela-height vs. body-weight relationship were found for single species, whereas the relationship between the three species differed significantly. Thus, for each species a regression function is given, valid for the whole North Sea, that allows estimations of the body weight of the three hermit-crab species from measuring the chela height alone.
Variations in the distributions of Centropages chierchiae and Temora stylifera (Copepoda: Calanoida) in the north-eastern Atlantic Ocean and western European shelf waters
Authors: Lindley J.A. , Daykin S. 
Published: May 2005

Abstract
Centropages chierchiae and Temora stylifera occurred rarely in the Continuous Plankton Recorder (CPR) survey in the Bay of Biscay, Celtic Sea, and English Channel before 1988. By 2000 they were found frequently and in abundance. The seasonal cycles of abundance of these species differ, C. chierchiae occurring mainly in the summer while T. stylifera was found most frequently in late autumn or winter towards the northern limits of its distribution. The increase in abundance of both species is related to temperature. However, in the years when it was found in the samples, the frequency of occurrence of C. chierchiae was correlated positively with the strength of the shelf edge current and negatively with the North Atlantic Oscillation (NAO) while the reverse was true for T. stylifera.
Immunoglobulin gene segment usage, location and immunogenicity in mutated and unmutated chronic lymphocytic leukaemia
Authors: Mauerer Katja , Zahrieh David , Gorgun Gullu , Li Aihong , Zhou Jianbiao , Ansén Sascha , Rassenti Laura Z. , Gribben John G. 
Published: May 2005

SummaryThe mutational status of the variable region of the immunoglobulin heavy chain gene (IgVH) is an important prognostic marker in B‐cell chronic lymphocytic leukaemia (B‐CLL), with mutated patients having improved outcome. To examine the impact of mutational status on VH, DH, and JH gene segment location and immunogenicity, we analysed 375 IgH sequences from 356 patients with B‐CLL. Although VH and DH gene usage was different in mutated compared to unmutated patients, there was no impact of gene location on frequency of use or clinical outcome. Surprisingly, somatic mutations did not increase the immunogenicity of the Ig, as assessed by predicted binding affinity of Ig‐derived peptides to major histocompatibility Class I and Class II molecules. Even excluding patients using VH1‐69, cases using the VH1 gene family had a poor outcome. Both mutated and unmutated CLL patients demonstrated evidence of antigen selection. The worst outcome was seen in the subset of 14 unmutated patients with similar HCDR3 amino acid sequence using VH1‐69, DH3‐3 and JH6, suggesting an antigen‐driven process modulating the clinical course.
Chimaerism analyses and subsequent immunological intervention after stem cell transplantation in patients with juvenile myelomonocytic leukaemia
Authors: Yoshimi Ayami , Niemeyer Charlotte M. , Bohmer Viktoria , Duffner Ulrich , Strahm Brigitte , Kreyenberg Hermann , Dilloo Dagmar , Zintl Felix , Claviez Alexander , Wössmann Willi , Kremens Bernhard , Holter Wolfgang , Niethammer Dietrich , Beck James F. , Kontny Udo , Nöllke Peter , Klingebiel Thomas , Bader Peter 
Published: May 2005

SummaryChimaerism analysis was performed by polymerase chain reaction amplification of short‐tandem repeat markers in 30 children following haematopoietic stem cell transplantation for juvenile myelomonocytic leukaemia (JMML). Fourteen patients always had complete chimaerism (CC); one of them relapsed after the discontinuation of the study and 13 continued in complete remission (CR). Mixed chimaerism (MC) was noted in 16 patients. Of those 12 patients demonstrated increasing MC (i‐MC); 10 relapsed and two achieved CC following discontinuation of immunosuppressive therapy (IST). Four other patients demonstrating only transient MC are alive in CR. MC with up to 20% of autologous cells could be successfully eradicated without induction of severe graft‐versus‐host disease when IST was reduced or discontinued directly after the first demonstration of MC. At the same time, MC with up to 10% of autologous cells could disappear without intervention. The interval between MC and relapse ranged from 0–320 d (median 38 d). Donor leucocyte infusion was given to six patients with i‐MC, but only one patient responded. Peripheral blood seems as valuable as bone marrow for chimaerism studies. In conclusion, serial quantitative chimaerism studies can identify patients with i‐MC who are at high risk for relapse of JMML. Immediate withdrawal of IST is advised in these patients.
The absence of CD56 on malignant plasma cells in the cerebrospinal fluid is the hallmark of multiple myeloma involving central nervous system
Authors: Chang Hong , Bartlett Eric S , Patterson Bruce , Chen Chris I , Yi Qi Long 
Published: May 2005

SummaryBy immunohistochemistry, the CD56‐positive myeloma cells were detected in three (38%) bone marrow (BM) and one (13%) cerebrospinal fluid (CSF) samples from eight patients with multiple myeloma involving the central nervous system (CNS MM). Of the three patients with CD56‐positive BM myeloma cells, two had CSF myeloma cells negative for CD56. In a control cohort of 84 MM patients without CNS involvement, the BM myeloma cells were CD56‐positive in 68 (80%) cases (P < 0·0001). The prevalence of CD56‐negative myeloma cells in the BM and CSF of our patients suggests that CD56 downregulation may play a role in the pathogenesis of CNS MM.
Host immune reactions and worm kinetics during the expulsion of Ascaris suum in pigs
Authors: Miquel N. , Roepstorff A. , Bailey M. , Eriksen L. 
Published: May 2005

SUMMARY Pigs single inoculated with Ascaris suum eggs expel the majority of larvae between days 14 and 21 post inoculation (p.i.), but the role of the immune system in expulsion is unclear. To investigate the dynamics of immune responses before, during and after the expulsion of A. suum larvae, pigs inoculated with 10 000 A. suum eggs were sequentially necropsied. Ascaris suum gradually moved distally from days 10–14 p.i. and only a few larvae were left by day 21 p.i. Pronounced increases in mucosal A. suum‐specific IgA antibody secreting cells (ASCs) were already found by day 10 p.i. especially in the proximal jejunum, while only small increases in parasite‐specific IgM ASCs were observed by day 21 p.i. in both proximal and distal jejunum. No mucosal IgG ASC responses could be detected. Increases in systemic A. suum‐specific IgG1, IgM and to a lesser extent IgA antibodies were observed, while IgG2 remained almost unchanged. The levels of eosinophils and mast cells in the small intestinal mucosa did not change throughout infection. The results demonstrate that both systemic and mucosal A. suum‐specific effector mechanisms are strongly stimulated in A. suum single infections and indicate that mucosal IgA may be an important mediator in the expulsion of A. suum.
Immuno‐epidemiology ofAscaris lumbricoidesinfection in a high transmission community: antibody responses and their impact on current and future infection intensity
Authors: King E.‐M. , Kim H. T. , Dang N. T. , Michael E. , Drake L. , Needham C. , Haque R. , Bundy D. A. P. , Webster J. P. 
Published: May 2005

SUMMARYThe role of the humoral immune system in human infection withAscaris lumbricoidesremains unclear. This study documents an epidemiological investigation in a highly endemic community in Vietnam, whereby serum antibody levels were assessed before treatment and after a 6‐month reinfection period. These data were examined by correlation with infection status using an age‐structured approach in an attempt to help shed light on the role of the humoral immune response. The first part of this study characterized levels of all serum antibody isotypes from the community in response to antigens of both adult and larvalA. lumbricoides.Data were assessed in terms of their relation to host age and infection intensity with the aim to provide a broadly detailed account of immune responses to the parasite. In the second part, antibody responses to both life‐stages ofA. lumbricoidesin serum samples collected before anthelmintic chemotherapy were analysed in relation to intensity of re‐infection with the parasite 6 months following treatment. The results suggest that antibody responses may not confer protection from current infection or re‐infection withA. lumbricoidesand may not serve as reliable indicators of future infection intensity. Our results thereby lend support to the theory that immunity toA. lumbricoidesmay not be based on the humoral immune system.
Anaphylaxis during anesthesia: results of a 12‐year survey at a French pediatric center
Authors: Karila C. , Brunet‐Langot D. , Labbez F. , Jacqmarcq O. , Ponvert C. , Paupe J. , Scheinmann P. , de Blic J. 
Published: May 2005

Background:  Following adverse reactions to anesthesia, tests are carried out to determine the mechanism of the reaction and to identify the agent responsible. No specific data are available in France concerning such skin tests in children.Methods:  Between 1989 and 2001, we assessed hypersensitivity reactions to general anesthesia in 68 children. Thirty underwent more than one operation, for congenital malformations. Immunoglobulin (Ig)E‐mediated anaphylaxis was diagnosed on skin tests combined with the clinical history.Results:  Grade I, II and III reactions were observed in 20, 27 and 21 children, respectively. IgE‐mediated anaphylaxis was diagnosed in 51 children: 31 (60.8%) for neuromuscular blocking agents (NMBA), 14 (27%) for latex, seven (14%) for colloids, five (9%) for opioids and six (12%) for hypnotics. Vecuronium was the NMBA causing the largest number of reactions. Cross reactivity to NMBA available in France was observed in 23 of 30 children (76%), particularly for vecuronium and atracurium or pancuronium.The estimated frequency of IgE mediated anaphylactic reactions was one in 2100 operations. Based on our results, 25 children subsequently received a different anesthetic with no adverse reaction.Conclusions:  As in adults, NMBA, then latex were responsible for most anaphylactic reactions during anesthesia. Our results confirm that skin tests with anesthetic agents are feasible and safe in children and improve the safety of subsequent anesthetic procedures.