bluuebunny/crossref_metadata_2025_split huggingface dataset:
The order‐disorder phase transformation in ion‐irradiated rare earth sesquioxide Dy2O3
Authors: Tang M. , Lu P. , Valdez J. A. , Stanek C. R. , Sickafus K. E. 
Published: March 2007

AbstractIn this report, we examine an irradiation‐induced order‐disorder phase transformation in polycrystalline pellets of the rare earth sesquioxide Dy2O3 using grazing incidence X‐ray diffraction (GIXRD) and transmission electron microscopy (TEM). This sesquioxide is characterized by a cubic C ‐type rare earth structure known as bixbyite. Samples were irradiated with heavy ion Kr++ (300 keV) at cryogenic temperature. GIXRD and cross‐sectional TEM observations reveal that the ordered body‐centered cubic bixbyite structure transforms to a disordered (anion deficient) fluorite structure in this irradiated sesquioxide. This observation is consistent with a radiation‐induced disordering process in which the oxygen superlattice associated with the bixbyite structure is destroyed and the material adopts an anion disordered fluorite structure as evidenced by the disappearance of characteristic GIXRD diffraction peaks resulting from ordering of the oxygen superlattice, and similar electron diffraction pattern features. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
XAFS and neutron diffraction study of the La1–xSrxCoO3
Authors: Efimov V. , Efimova E. , Karpinsky D. , Kochubey D. I. , Kriventsov V. , Kuzmin A. , Molodtsov S. , Sikolenko V. , Tiutiunnikov S. , Troyanchuk I. O. , Shmakov A. N. , Vyalikh D. 
Published: March 2007

AbstractWe have studied the effects of hole doping on the crystal and electronic structure of the La1–xSrxCoO3 (x = 0.0 ÷ 0.5) by neutron Rietveld analysis and its correlation with the X‐ray‐absorption spectroscopy data. The abrupt decrease of the Co–O distance and an increase of the Co–O–Co angle upon substitution of La3+ by Sr2+ in La1–xSrxCoO3 are attributed to a change in the band structure at the transition from semiconducting to metallic state. Upon strontium doping, a variation of Co L2,3‐edges in La1–xSrxCoO3 series suggests an increase of the mixed low Co4+ and high or intermediate Co3+ spin states. The possible explanation of the observed changes of the crystal and electronic structure in these cobaltites is discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Time resolved luminescence of solids excited by femtosecond VUV pulses and synchrotron radiation
Authors: Kirm M. , Babin V. , Feldbach E. , Nagirnyi V. , Vielhauer S. , Guizard S. , Carré B. , De Grazia M. , Merdji H. , Belsky A. N. , Fedorov N. , Martin P. 
Published: March 2007

AbstractTime‐resolved luminescence spectroscopy has been widely used in studies of electronic excitations and their dynamics in insulators. Present paper discusses the potential of vacuum ultraviolet spectroscopy applied for wide band gap crystals using classical synchrotron radiation as well as more recently developed pulsed femtosecond short‐wavelength light sources. Optical spectroscopy using novel free electron lasers and laser systems based on higher harmonic generation process allow detailed investigation of the interaction between electronic excitations and behaviour of solids under extreme radiation conditions. Significant changes in the quantum yield and emission decay kinetics as well as surface damage of single crystals were observed for CdWO4 and CaWO4 crystals studied in the temperature range of 8‐300 K. However, in the range of excitation densities applied, up to ∼1012 W/cm2, the nature of luminescence centres and their characteristic emission spectra remained similar to those observed at low excitation densities. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of deep traps on the optical properties of Tb3+ doped sol‐gel silica
Authors: Fasoli Mauro , Chiodini Norberto , Lauria Alessandro , Moretti Federico , Vedda Anna 
Published: March 2007

AbstractIn this study we investigate the role of traps on radio‐ and photo‐luminescence properties of terbium doped silica. The investigation is motivated by the promising characteristics of rare‐earth doped silica obtained by the sol‐gel technique as scintillating material. We focus on those phenomena that can be responsible for problematic properties such as the increase of radio‐luminescence sensitivity following repeated irradiations. A set of terbium doped silica with different terbium concentrations (0.03 mol%, 0.1 mol% and 10 mol%) prepared by the sol‐gel technique and densified at 1050 °C in oxidizing atmosphere has been considered. The effect of a post‐densification rapid thermal treatment on the RL and PL properties has also been investigated. This treatment improved the scintillation characteristics of the samples reducing their RL instability under prolonged irradiation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles modelling of defects in advanced nuclear fuels
Authors: Kotomin E. A. , Mastrikov Yu. A. , Zhukovskii Yu. F. , Van Uffelen P. , Rondinella V. V. 
Published: March 2007

AbstractThe cover picture of this issue of physica status solidi (c) has been taken from the article [1]. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum chemical investigation of donor–acceptor complexes of trimethylaluminum with Lewis bases of group 15 elements
Authors: Zagidullina Aygul E. , Vakulin Ivan V. , Vostrikova Olga S. , Talipov Rifkat F. 
Published: March 2007

AbstractLewis acid–base complexes AlMe3‐YH3 (Y = N, P, As) and their components have been investigated by means of quantum chemical techniques at the RHF, MP2, MP4, and DFT (PBE0) levels of theory, using the cc‐pVDZ and cc‐pVTZ basis sets. Theoretical complex formation energy for the AlMe3‐YH3 complexes increases in the order NH3 ≪ PH3 < AsH3 for all investigated complexes. Distortion of AlMe3 from planarity under complex formation leads to decreasing CAlC angles along with increasing AlC bond length. For all investigated adducts, an inverse negative relationship correlation between YAlC valence angle and AlY bond length has been found. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Meta‐analysis of putative human bornavirus sequences fails to provide evidence implicating Borna disease virus in mental illness
Authors: Dürrwald Ralf , Kolodziejek Jolanta , Herzog Sibylle , Nowotny Norbert 
Published: March 2007

AbstractAll Borna disease virus (BDV) sequences derived from human specimens published till date were thoroughly analysed and compared to sequences of BDV laboratory strains and to BDV sequences from animals which succumbed to classical Borna disease (BD). Despite high sequence conservation of the BDV genome, animal‐derived BDV sequences clustered according to their geographic origin. However, in marked contrast, human‐derived BDV sequences did not cluster according to their geographic origin but showed high sequence identities to BDV laboratory strains and animal‐derived BDVs handled in the laboratories reporting the human strains. Japanese, US, Australian and French human‐derived BDV sequences proved to be identical or very similar to animal‐derived BDV sequences from Germany, although the human specimens were collected hundreds to thousands of miles away from the central European BD endemic regions. These findings suggest that previous studies linking BDV to human neuropsychiatric disease may have been compromised by inadvertent sample contamination. Copyright © 2007 John Wiley & Sons, Ltd.
Early stopping designs based on progression‐free survival at an early time point in the initial cohort
Authors: Litwin Samuel , Wong Yu‐Ning , Hudes Gary 
Published: March 2007

AbstractWe introduce a new study design in which patients are evaluated early in their treatment for disease progression. Our design is appropriate when lack of progression, both early and late, is the criterion for treatment success. An initial cohort of n1 patients is followed until the last one has been evaluated. If enough of these patients are progression free (PF) at an early time point, t1 after arrival, a second cohort is recruited until n2 total patients are evaluable for PF survival at the final time t2. Otherwise, the trial is terminated for futility both early in time and with a minimal number of patients. Patients in the initial cohort who are PF at t1 continue on study and are again evaluated at t2. The design permits early stopping for rapid progression of disease, an indication of futility both for cytotoxic and newer non‐cytotoxic targeted therapies. The design tests the composite hypothesis of a probability p1 of being PF at t1 and p2 of being PF at t2 given PF at t1. Power and type I error are maintained at design point levels over a wide range of parameters p1 and p2. No distributional assumptions are needed other than the binomial, so the design provides rigorous power analysis for this type of study. Tables of optimal designs are supplied for a broad range of requirements. Copyright © 2007 John Wiley & Sons, Ltd.
An evolvable oestrogen receptor activity sensor: development of a modular system for integrating multiple genes into the yeast genome
Authors: Fox Jennifer E. , Bridgham Jamie T. , Bovee Toine F. H. , Thornton Joseph W. 
Published: March 2007

AbstractTo study a gene interaction network, we developed a gene‐targeting strategy that allows efficient and stable genomic integration of multiple genetic constructs at distinct target loci in the yeast genome. This gene‐targeting strategy uses a modular plasmid with a recyclable selectable marker and a multiple cloning site into which the gene of interest is cloned, flanked by two long regions of homology to the target genomic locus that are generated using adaptamer primers. We used this strategy to integrate into a single yeast strain components of the oestrogen receptor (ER) signalling network, comprising the human ERα and three reporter genes driven by oestrogen response elements (EREs). The engineered strain contains multiple reporters of ligand‐dependent receptor signalling, providing sensitive, reproducible, rapid, low‐cost quantitative assays of ERα activity in order to screen potential receptor agonists. Further, because two of the ERE‐driven reporter genes are required for growth in deficient media, the strain's growth rate—and therefore its fitness—depends on ligand‐induced ERα activity. This evolvable oestrogen receptor activity sensor (EERAS) can therefore provide the foundation of a long‐term experimental evolution strategy to elucidate ER structure–function relations and ligand‐receptor evolution. Copyright © 2007 John Wiley & Sons, Ltd.
Role in anaerobiosis of the isoenzymes for Saccharomyces cerevisiae fumarate reductase encoded by OSM1 and FRDS1
Authors: Camarasa Carole , Faucet Virginie , Dequin Sylvie 
Published: March 2007

AbstractSaccharomyces cerevisiae possesses both a cytoplasmic and a mitochondrial fumarate reductase, encoded by FRDS1 and OSM1, respectively. While previous studies have shown that mutants lacking FRDS1 and OSM1 cannot grow under anaerobiosis (Arikawa et al., 1998), the physiological role of fumarate reductase (FR) remains poorly understood. Here, we report that an osm1 frds1 mutant is unable to grow anaerobically, even with glutamate as a sole nitrogen source, when succinate can be produced by the TCA oxidative branch. We also show that the growth of the mutant is not restored by adding acetoin, an alternative sink for NADH oxidation, but it is at least partly restored by the addition of oxygen or menadione, which can oxidize FADH2 in addition to NADH. These data indicate that the growth inhibition of the mutant is due to an inability to reoxidize FAD, rather than an indirect effect on NADH or an inability to produce succinate per se. During anaerobic growth, FRDS1 expression was two to eight times higher than that of OSM1, and fumarate reductase activity was higher in the osm1 mutant than in the frds1 mutant. FRDS1 expression was induced by anaerobiosis, and this induction was abolished in a rox1 mutant. We conclude that the formation of succinate is strictly required for the reoxidation of FADH2 during anaerobiosis, and that it is regulated through the control of FRDS1 expression when oxygen is limiting. Based on these data, we discuss the potential role of fumarate reductase in the regeneration of the FAD‐prosthetic group of essential flavoproteins. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis, Spectroscopy and Crystal Structures of Chiral Organic Ammonium Tetrathiometalates Showing N‐H···S and C‐H···S Interactions
Authors: Srinivasan Bikshandarkoil R. , Naik Ashish R. , Näther Christian , Bensch Wolfgang 
Published: March 2007

AbstractThe reaction of ammonium tetrathiometalate (NH4)2[MS4] (M = W or Mo) with the R(+) or S(−) forms of the organic amine α‐methylbenzylamine [PhCH(CH3)NH2] results in the formation of the corresponding non‐centrosymmetric bis(α‐methylbenzylammonium) tetrathiometalate complexes [PhCH(CH3)NH3]2[MS4] (R‐ammonium M = W 1; R‐ammonium M = Mo 2; S‐ammonium M = W 3, S‐ammonium M = Mo 4) which were characterized by elemental analysis, IR, Raman, UV‐Vis and CD spectra, X‐ray powder diffractometry and single crystal X‐ray crystallography. Compounds 1‐4 crystallize in the chiral space group P21 and constitute the first examples of structurally characterized chiral organic ammonium group VI tetrathiometalates. The structures of 1‐4 consist of two crystallographically independent chiral organic ammonium cations and a tetrahedral tetrathiometalate dianion. The N‐H···S and C‐H···S interactions between the anions and cations organise them such that the organic ammonium ions always point towards the S atoms of [MS4]2−.
Synthesis and Crystal Structure of [Pb(trz)(tfpb)(H2O)]: a Lead(II) Complex Containing 2,4,6‐Tris(2‐pyridyl)‐1,3,5‐triazine and 4,4,4‐Trifluoro‐1‐phenyl‐1,3‐butandionate
Authors: Marandi Farzin , Asghari Nasim , Gorbanloo Massomeh , Soudi Ali A. , Mayer Peter 
Published: March 2007

Abstract[Pb(trz)(tfpb)(H2O)] (1) (trz and tfpb are the abbreviations of 2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine and 4,4,4‐trifluoro‐1‐phenyl‐1,3‐butandionate, respectively) have been synthesized and characterized by elemental analysis and IR, 1H NMR, spectroscopy. The single‐crystal structure of 1 shows the coordination number of the Pb2+ ions is eight with three N‐donor atoms from a “trz” ligand and four O‐donors from the dionate ligand and one molecule of water. The supramolecular features in this complex are guided by lone pair activity and control of strong hydrogen bonds, weak directional intermolecular interactions and aromatic π‐π stacking interactions.
Labile Interactions in Aza‐aromatic Base Adducts of Lead(II) Thenoyltrifluoroacetonate
Authors: Marandi Farzin , Morsali Ali , Soudi Ali A. 
Published: March 2007

AbstractThe polymeric form of lead(II) thenoyltrifluoroacetonate, [Pb(ttfa)2], is modified by adduct formation with 2,2′‐bipyridine (bipy) and 1,10‐phenanthroline (phen) to give, in both cases, dimeric species [Pb2(bipy)2(ttfa)4] and [Pb2(phen)2(ttfa)4], respectively. Crystal structure determinations indicate that labile interactions involving the fluorine atoms and both the thenoyl and aza‐aromatic moieties may be important in determining the lattice arrays of these dimers, which are very similar, even though the dominant lattice forces may differ.
Metallation of Ligands with Biological Activity: Synthesis and X‐ray Characterization of the New Sulfathiazolato Complexes of Gold(I) and Silver(I): [(sulfathiazolato)AuPPh3] and [Ag(sulfathiazolato)]2 (sulfathiazole = N1‐2‐thiazolyl‐sulfanilamide)
Authors: de Oliveira Gelson Manzoni , Soccol Gris Lara Regina , de Lourenço Marques Lenice , Schulz Lang Ernesto 
Published: March 2007

AbstractSulfathiazole reacts with [Ph3PAu(CH3COO)] in benzene and with Ag(CH3COO) in methanol giving [(sulfathiazolato)AuPPh3] (1) and {[Ag(sulfathiazolato)]2}n (2). While the lattice of 1 contains single molecules with linear N–Au–P bonds, compound 2 performs a polymeric, one‐dimensional assembling of [Ag(sulfathiazolato)]2 dimers linked through intermolecular Ag···O=S=O interactions along the crystallographic axis b. The silver atoms achieve a tetrahedral configuration through Ag–Ag contacts which measure 2.8427(4) Å, considerably shorter than the normal bonding distance of metallic silver.
Transient Bloodletting of the Short Gastric Vein in the Reconstructed Gastric Tube Improves Gastric Microcirculation During Esophagectomy
Authors: Kono Koji , Sugai Hidemitsu , Omata Hideo , Fujii Hideki 
Published: March 2007

AbstractBackgroundThe reasons for anastomotic leakage in esophago‐gastrostomy have been proposed to be poor arterial inflow and insufficient venous drainage at the anastomotic site. In order to improve the congestive status, we developed a novel and easy surgical procedure of transient bloodletting from the short gastric vein after making a gastric tube during esophagectomy, and evaluated tissue blood flow.MethodsPatients with esophageal cancer, who had received transthoracic esophagectomy and gastric tube reconstruction with intrathoracic anastomosis, were enrolled. After making a slender gastric tube, transient bloodletting from the short gastric vein at the most cardiac site was performed for 30 minutes. The tissue blood flow of the proximal end of the gastric tube was measured using a laser Doppler flowmeter, and was compared in the bloodletting group (n = 68) and the control group without bloodletting (n = 8).ResultsIn the bloodletting group, tissue blood flow 5 minutes after the start of bloodletting was markedly increased in comparison to that before bloodletting (9.5 ± 4.9 ml/min/100 g vs. 24.1 ± 5.9 ml/min/100 g). The elevated levels of tissue blood flow remained at almost constant levels after ceasing bloodletting and lasted until esophago‐gastrostomy (20.1 ± 3.9 ml/min/100 g). On the contrary, in the control group without bloodletting, tissue blood flows were marginally increased following construction of a gastric tube, but the changes did not reach significant levels. When the tissue blood flow just before esophago‐gastrostomy was compared in the bloodletting and control groups, the flows in the bloodletting group were significantly more elevated than those in the control group (20.1 ± 3.9 vs. 15.2 ± 4.9 ml/min/100 g).ConclusionsTransient bloodletting of the short gastric vein in the gastric tube during esophagectomy may improve the microcirculation of the oral side of the gastric tube.
Development of Small‐Diameter Vascular Grafts
Authors: Wang Xinwen , Lin Peter , Yao Qizhi , Chen Changyi 
Published: March 2007

AbstractIntroductionCardiovascular disease, including coronary artery and peripheral vascular pathologies, is the leading cause of mortality in the United States and Western countries. There is a pressing need to develop small‐diameter vascular vessels for bypass surgery and other vascular reconstructive procedures. Tissue engineering offers the prospect of being able to meet the demand for replacement of diseased vessels. Significant advances have been made in recent studies and provide confidence that success is attainable. For instance, a completely cellular approach culturing cells into tissue sheets and wrapping these layers was able to form a layered cellular vascular graft with impressive strength.Methods/ResultsIn our experiments, decellularization and heparin immobilization grafts from porcine tissues implanted in a canine model could be repopulated from the host cells, indicating the grafts’ potential to develop into living tissues that can adapt and respond to changes in the body.ConclusionsThis review summarizes the current status of vascular grafts used clinically, updates the most recent developments on vascular tissue engineering, and discusses the challenges for the future.
Peripheral Arterial Occlusive Disease: Magnetic Resonance Imaging and the Role of Aggressive Medical Management
Authors: Lumsden Alan B. , Rice Terry W. , Chen Changyi , Zhou Wei , Lin Peter H. , Bray Paul , Morrisett Joel , Nambi Vijay , Ballantyne Christie 
Published: March 2007

AbstractAtherosclerosis accounts for most peripheral arterial occlusive disease (PAD). Although many of the risk factors for atherosclerotic coronary artery disease (CAD) such as hyperlipidemia have been identified as risk factors for peripheral arterial disease, strong evidence is lacking that risk factor modification is effective in halting progression or improving outcomes. A better understanding is needed regarding the clinical and pathophysiologic responses to risk factor modification. This review describes current advances in the medical management for PAD including lipid modification antiplatelet therapy, angiotensin‐converting enzyme (ACE) inhibitors, beta‐blockers, exercise, and endovascular intervention. In addition, we discuss our active ELIMIT Trial (Effect of Lipid Modification on Peripheral Arterial Disease after Endovascular Intervention). We test the hypothesis that an aggressive regimen of serum lipid modification will inhibit the progression of atherosclerosis in femoral arteries and reduce the incidence of restenosis of femoral arteries following endovascular stenting by decreasing thrombosis and inflammation. This study will provide a novel strategy for retarding or preventing progression of atherosclerosis and re‐stenosis of peripheral arterial disease following arterial revascularization procedures. Importantly, our magnetic resonance imaging studies will provide quantitative data on the vascular lesions in PAD. These studies will advance our understanding of the molecular mechanisms of inflammation and thrombosis associated with aggressive lipid modification.
Special Variants of Differentiated Thyroid Cancer: Does It Alter the Extent of Surgery Versus Well‐Differentiated Thyroid Cancer?
Authors: Carling Tobias , Ocal Idris T. , Udelsman Robert 
Published: March 2007

AbstractIntroductionRecently, more aggressive variants of so‐called well‐differentiated thyroid carcinomas have been identified such as the tall cell variant, columnar cell variant, diffuse sclerosing variant, insular carcinoma, and Hürthle cell (oncocytic, oxyphilic) carcinomas.MethodsAn evidence‐based review was performed to identify the optimal treatment recommendations for these thyroid cancers of intermediate differentiation.ConclusionsAlthough some variation exists within the group, aggressive surgical and medical management are recommended for these neoplasias. Any such recommendations should, however, be viewed in the light of the fact that the current literature mainly consists of case reports, case series, and limited reviews. The clinical presentation, pathophysiology, diagnosis, and surgical and medical management for these thyroid cancers with intermediate differentiation are discussed.