bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanistic Study of a Pd/C‐Catalyzed Reduction of Aryl Sulfonates Using the Mg–MeOH–NH4OAc System
Authors: Mori Akinori , Mizusaki Tomoteru , Ikawa Takashi , Maegawa Tomohiro , Monguchi Yasunari , Sajiki Hironao 
Published: October 2006

AbstractA method for the deoxygenation of phenolic hydroxy groups via aryl triflates or mesylates has been established by using a combination of Pd/C–Mg–MeOH. The addition of NH4OAc to the system markedly accelerated the reaction rate and expanded the scope of the reaction. Mechanistic studies suggested that a single‐electron transfer process from the Pd0 center to the benzene ring is involved in the reduction of aryl sulfonates and that NH4OAc works as a solubilization reagent of the Mg salt and as an accelerator of the electron transfer, thus enhancing the reaction process. Our method was also applicable to the regioselective deuteration of benzene derivatives with CH3OD as the solvent and deuterium source: the original hydroxy group could be efficiently replaced with a deuterium atom.
Theoretical Investigations on the Geometric and Electronic Structures of Phenylene‐Acetylene Macrocycles
Authors: Li Yanwei , Zhao Jianwei , Yin Xing , Yin Geping 
Published: October 2006

AbstractThe geometric and electronic structures of a series of conjugated macrocycles (phenylene‐acetylene macrocycles, PAMs) have been studied theoretically with ab initio and semiempirical molecular orbital methods. The ab initio calculations at the HF/6‐31G* level demonstrate that the model molecules may have a planar conformation. Bigger macrocycles, for example, 7PAM, 8PAM, and 9PAM, result in several energy minima. The boatlike conformation is the most energetically favored form. Based on the conformational analysis, a novel method for analyzing the ring‐strain energy was proposed and used. In view of their potential applications as electronic materials, the electronic structures of a series of PAMs are also investigated. The LUMO–HOMO gaps of the planar PAMs show an odd–even difference behavior. In addition, the HOMOs of the planar species 3PAM, 5PAM, 7PAM, and 9PAM are doubly degenerated.
Temperature Dependence of Ultra‐Exothermic Charge Recombinations
Authors: Serpa Carlos , Gomes Paulo J. S. , Arnaut Luis G. , de Melo J. Seixas , Formosinho Sebastião J. 
Published: October 2006

AbstractWe measured the temperature dependence (from +32 to −50 °C) of charge‐recombination rates between contact radical ion pairs in isopropyl ether. In the systems selected for this study, aromatic hydrocarbon cations are the electron acceptors and the fumaronitrile anion is the electron donor. Nearly quantitative electron transfers occur at all temperatures. The charge recombinations have excess exothermicities of −60 kcal mol−1 and exhibit a very weak temperature dependence. Our observations emphasize the absence of solvent effects and the relevance of nuclear tunneling in charge recombinations.
Inconsistencies in the self‐report of traumatic experiences by unaccompanied refugee minors
Authors: Spinhoven Philip , Bean Tammy , Eurelings‐Bontekoe Liesbeth 
Published: October 2006

AbstractThe authors investigated the consistency with which stressful life events are reported by unaccompanied refugee minors during a 12‐month follow‐up period and analyzed to what extent demographic and psychopathology variables affected memory consistency. From a population‐based sample of 920 unaccompanied refugee minors aged 12 to 18 years old, 63% completed the follow‐up measurements. Younger participants and those with lower levels of internalizing behavior and posttraumatic stress at follow‐up were more prone to memory inconsistencies. Moreover, younger participants and those with fewer inconsistencies were more likely to have obtained a temporary residence permit. Given the difference between accuracy and consistency, it is not warranted to interpret memory inconsistencies as an indication of lack of credibility when assessing traumatic life events in minors applying for asylum.
Low predictive power of peritraumatic dissociation for PTSD symptoms in accident survivors
Authors: Wittmann Lutz , Moergeli Hanspeter , Schnyder Ulrich 
Published: October 2006

AbstractTo test the predictive power of peritraumatic dissociation for the development of psychopathology, the authors assessed symptoms of peritraumatic dissociation (Peritraumatic Dissociative Experiences Questionnaire; PDEQ), posttraumatic stress disorder (Clinician‐Administered PTSD Scale; CAPS), anxiety and depression (Hospital Anxiety and Depression Scale; HADS) in a sample of 214 accident victims 5 days postaccident (T1). Six months later (T2), CAPS and HADS were administered again. Acute stress disorder (ASD) and PTSD symptom levels were surprisingly low. In sequential regression analyses, initial reexperiencing and hyperarousal significantly predicted PTSD symptom level (T2) over several possibly confounding variables controlled for. Peritraumatic dissociation explained less than 3% of variance. For PTSD scores, 38% overall variance explanation was obtained; the variance for HADS scores was low. Possible explanations for the low‐predictive power of peritraumatic dissociation for posttraumatic psychopathology in the sample are discussed.
Systematic review and meta‐analysis of clinically relevant adverse events from HMG CoA reductase inhibitor trials worldwide from 1982 to present
Authors: McClure David L. , Valuck Robert J , Glanz Morton , Hokanson John E. 
Published: October 2006

AbstractPurposeOur objective was to determine the association of clinically relevant adverse events from a systematic review and meta‐analysis of statin randomized controlled trials (RCT).MethodsWe performed the meta‐analysis in the manner of a Cochrane Collaboration systematic review. Outcomes were discontinuances of therapy or muscle‐related symptoms due to adverse events. We searched for articles from 1982 through June 2006 in MEDLINE and other databases. The main inclusion criteria were double blind, placebo controlled RCTs with a monotherapy intervention of any marketed statin and active surveillance of adverse events. We excluded studies of drug interactions, organ transplants, or exercise, or those not meeting all of the study quality criteria. The primary analysis was a statin formulation stratified fixed‐effect model using Peto odds‐ratios (POR). Secondary analyses explored the stability of the primary results.ResultsOver 86 000 study participants from 119 studies were included. Available statins were associated with a lower POR of discontinuance (overall: 0.88 [0.84, 0.93], largest effect with pravastatin: 0.79 [0.74, 0.84]), an elevated POR of rhabdomyolysis (1.59 [0.54, 4.70]) and myositis (2.56 [1.12, 5.85]), and null odds of myalgia (1.09 [0.97, 1.23]). Cerivastatin by comparison demonstrated larger PORs for discontinuances and muscle‐related adverse events. Secondary analyses demonstrated the stability of the results.ConclusionsOverall, discontinuation of statin therapy due to adverse events was no worse than placebo. The risks of muscle‐related adverse events were in general agreement with the known risks of statins. Copyright © 2006 John Wiley & Sons, Ltd.
Surface properties of the (001) surface of cubic PbZrO3 and PbTiO3
Authors: Wang Yuan Xu 
Published: October 2006

AbstractThe (001) surface of cubic PbZrO3 and PbTiO3 with the PbO and B(Ti or Zr)O2‐terminations has been investigated using a plane wave ultrasoft pseudopotential method within the density functional theory. The results of the grand thermodynamic potential show that only the PbO‐terminated surface can exist. The different surface relaxation behavior of the PbO‐terminated surface between PbZrO3 and PbTiO3 is mainly due to the larger cell volume of cubic PbZrO3 than cubic PbTiO3. The different surface dipole moments between PbZrO3 and PbTiO3 with both types terminations are discussed. The surface states appear on the band structure of the PbO‐terminated surface for cubic PbZrO3. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence of anthracene molecules in single crystal matrices
Authors: Aoki‐Matsumoto T. , Furukawa C. , Hoshika Y. , Ichida M. , Mizuno K. 
Published: October 2006

AbstractOptical properties of single fluorene/phenanthrene crystals doped with various mole fraction of anthracene, 10–5 to a few %, were investigated at 10 K. In low concentration samples, sharp structures attributed to isolated anthracene molecules were observed. Inhomogeneous width in their 0‐0 energy were found to be ∼20 cm–1. When concentration is higher, spectral species, which are distinctly different from the isolated molecule spectrum, were observed and their origins are discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Force control between nanostructures by coupling of spatially separated polaritons
Authors: Iida Takuya , Ishihara Hajime 
Published: October 2006

AbstractWe theoretically propose a novel metrology technique based on the photomediated force control between nano‐objects. In order to demonstrate the potential of this concept, we develop the general theoretical framework based on the Lorentz force equation and the nonlocal theory to obtain a concise analytical expression of the interparticle radiation force (IRF) due to the induced fields from polaritons in different nano‐objects. This expression clearly shows how IRF reflects the electromagnetic coupling of spatially separated polaritons and contains information on the other nanostructure. This means that IRF can be used to access the multidirectional information of quantum properties in the target nanostructure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of energy transfer in disordered two‐dimensional mixed J‐aggregates
Authors: Lemaistre J. P. 
Published: October 2006

AbstractA theoretical model, based on numerical simulations, is provided to analyze the energy transfer in a two‐dimensional mixed J‐aggregate. The J‐aggregate is modeled as a square arrangement of parallel donor molecules in which a given concentration of acceptors is randomly substituted. The Frenkel exciton states are calculated by numerical diagonalization of the aggregate Hamiltonian including the static disorder. The scattering rates are calculated using a model of exciton‐phonon coupling. The concentration dependences of the absorption and fluorescence line shapes, the localization behavior of the exciton states and the time‐resolved fluorescence decays (configurationally averaged) are obtained. The simulations are checked against recent experimental results on mixed J‐aggregates of cyanine dyes. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Local level statistics for optical and transport properties of disordered systems at finite temperature
Authors: Malyshev A. 
Published: October 2006

AbstractIt is argued that the (traditional) global level statistics which determines localization and coherent transport properties of disordered systems (e.g. the Anderson model) at zero temperature becomes inappropriate when it comes to incoherent transport. We define local level statistics which proves to be relevant for finite temperature incoherent transport and optics of one‐dimensional systems (e.g. molecular aggregates, conjugated polymers, etc.). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of optical near field of a sub‐wavelength gold slit array and its electric quadrupole interaction with 1s excitons in Cu2O
Authors: Okuda M. , Deguchi K. , Iwamae A. , Nakamura H. , Sawada K. , Hasuo M. 
Published: October 2006

AbstractLaight propagation through a gold film with a periodically structured 50 nm width slit array into Cu2O has been calculated with a FDTD (Finite Difference Time Domain) method with a 5 nm mesh‐grid. Owing to the presence of a guided mode in the slit and a surface plasmon mode at the gold/Cu2O interface, optical near field generation in Cu2O are efficient in the case where the polarization of the incident light is perpendicular to the slit. The efficiency of the electric quadrupole (E2) transition of the 1s ‐exciton in Cu2O, which is modified by the field gradient of the excitation light, is evaluated for the calculated optical near field. Slit period dependences of the near field generation and the E2 transition efficiency are examined for a 50 nm thick array film. The enhancement of the effective E2 transition efficiency in the volume of 50 nm thickness above the film relative to the efficiency by the plane wave excitation is found to reach a factor 28 at the slit period of 110 nm. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microscopic calculation of polariton effects in molecular crystals – application to sexithiophene electroabsorption spectrum
Authors: Petelenz Piotr , Stradomska Anna 
Published: October 2006

AbstractAn explicit formula expressing the refractive index in terms of exciton energies and oscillator strengths is used to calculate the absorption spectrum of the crystal at zero and non‐zero electric field; the electroabsorption signal is calculated as their difference, without any a priori assumptions regarding the shape of the individual EA fingerprints. The approach is applied for the sexithiophene crystal. The results show that an isolated Frenkel exciton always yields a first‐derivative EA signal, regardless of its intensity, and that this conclusion is not affected by polaritonic effects. For the specific case of sexithiophene, a satisfactory theoretical reproduction of the EA spectrum is possible only when the low‐energy charge‐transfer states are included. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Inapplicability of the giant oscillator strength model to excitonic molecule in an inorganic‐organic layered semiconductor
Authors: Shimizu Makoto 
Published: October 2006

AbstractThe author reports the measurement of the resonant Rabi splitting of the transition between the exciton and the excitonic molecule in an inorganic‐organic layered semiconductor, (C6H13C2H4NH3)2PbI4. The transition dipole moment is determined to be 3.5 ± 0.4 eÅ. It is shown that the obtained transition dipole moment is considerably smaller than that estimated from the well‐known giant oscillator strength model. The discrepancy between the experiment and the model is explained to be due to the strong polaritonic effect. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Raman study of order‐disorder transition of bipolarons in Ti4O7
Authors: Watanabe Masayuki , Ueno Wakana 
Published: October 2006

AbstractWe have studied the phase transition of bipolarons in Ti4O7 by means of Raman spectroscopy. It is found that on warming across the phase transition, the Raman spectrum shows distinct changes, i.e., broadening of the linewidths, decrease in the phonon frequencies, and appearance of the fine structure. These features indicate the existence of structural disorder above the transition temperature, and hence are consisitent with a model that the phase transition is an order‐disorder transition of bipolarons. The mechanism of the line broadening is discussed in relation to the bipolaron motion in the disordered phase. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation of crack‐free nano‐crystalline yttria‐stabilized zirconia
Authors: Drings Harald , Brossmann Ulrich , Schaefer Hans‐Eckhardt 
Published: October 2006

AbstractIn recent research and development, yttria‐stabilized zirconia have become increasingly important for many industrial applications such as gas sensors and solid oxide fuel cells. In many of these applications, the suppression of uncontrolled gas transport due to porosity or cracks is essential. In this work, the influence of the sintering parameters on the crack formation in n‐ZrO2·9.5 mol% Y2O3, manufactured by room‐temperature compaction of sputtered ZrY nanocrystallites with subsequent oxidation and sintering, was studied. A procedure that enables the production of nearly crack‐free fully dense samples is presented. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cytoplasmic microtubule organization in fission yeast
Authors: Sawin Kenneth E. , Tran P. T. 
Published: October 2006

AbstractDuring the cell cycle of the fission yeast Schizosaccharomyces pombe, striking changes in the organization of the cytoplasmic microtubule cytoskeleton take place. These may serve as a model for understanding the different modes of microtubule organization that are often characteristic of differentiated higher eukaryotic cells. In the last few years, considerable progress has been made in our understanding of the organization and behaviour of fission yeast cytoplasmic microtubules, not only in the identification of the genes and proteins involved but also in the physiological analysis of function using fluorescently‐tagged proteins in vivo. In this review we discuss the state of our knowledge in three areas: microtubule nucleation, regulation of microtubule dynamics and the organization and polarity of microtubule bundles. Advances in these areas provide a solid framework for a more detailed understanding of cytoplasmic microtubule organization. Copyright © 2006 John Wiley & Sons, Ltd.
How to get the most from fission yeast genome data: a report from the 2006 European Fission Yeast Meeting computing workshop
Authors: Wood Valerie 
Published: October 2006

AbstractA fission yeast computing workshop ‘How to get the most from the fission yeast genome data’ was run as a satellite to the European Fission Yeast Meeting. The broad aims of the workshop were to provide fission yeast bench biologists with a set of tools and protocols to query the fission yeast genome data in specific ways, in order to extract biologically meaningful information of interest, which can be tailored to the needs of individual research projects. A description of the workshop content is provided and a selection of the tools presented are reviewed. Copyright © 2006 John Wiley & Sons, Ltd.
The forests and woodlands of Labrador, Canada: ecology, distribution and future management
Authors: Roberts Bruce A. , Simon Neal P. P. , Deering Keith W. 
Published: October 2006

AbstractLabrador, Canada is the last relatively undeveloped landmass of Boreal and subarctic Canada. Its land area is over 288,000 km2, with less than 1% developed, and a human population of below 30,000. Labrador is greater than 60% forest‐ and woodland‐covered and over 30% tundra, soil and rock barrens. We review the ecology and distribution of forests, woodlands, and related vegetation of Labrador within the context of climate, forest site index, landform, soils, and disturbance. Recent ecosystem management through a public planning process with emphasis on past and future comanagement and development with traditional and western scientific principles is currently underway. Plant–animal interactions, traditional uses by aboriginal groups, and early history are also reviewed.
Recent Outcomes and Perspectives of the Application of Bone Morphogenetic Proteins in Implant Dentistry
Authors: Salata Luiz A. , Franke‐Stenport Victoria , Rasmusson Lars 
Published: October 2006

ABSTRACT Background: Since the discovery of bone morphogenetic proteins (BMPs), the number of related studies has increased substantially, and more recent outcomes have cast encouraging perspectives on their use in reconstructive surgery. Purpose: The aim of the present review was to summarize the present knowledge about the use of BMPs in conjunction with dental implants based on the literature. Materials and Methods: Scientific articles dealing with the use of growth factors and bone healing with or without dental implants were searched for on MEDLINE and critically scrutinized. Results: Thirty‐nine scientific reports formed the base for the present review. Whereas the osteoinductive capability of BMPs is well documented, studies on their effects in implant dentistry are still incipient. Preclinical and clinical studies did not show outstandingly good outcomes of the application of BMPs compared with conventional treatments or controls. Conclusions: The number of studies in the field of dental implantology in which BMPs have been used is still too small for establishing clinical protocols of their use in order to improve a recipient bone bed prior to implant placement or to enhance the integration process of an implant.
Early Loading of Machined‐Surf ace Brånemark Implants in Completely Edentulous Mandibles: Healed Bone versus Fresh Extraction Sites
Authors: De Bruyn Hugo , Collaert Bruno 
Published: October 2006

ABSTRACT Background: Restoration of edentulous mandibles with dental implants installed with a two‐stage or one‐stage surgical approach, yet with delayed loading, is a predictable and successful treatment. Purpose: The present prospective study evaluated the success up to 3 years of function of nonroughened machined‐surface Brånemark System implants (Nobel Biocare AB, Gothenburg, Sweden) loaded early or immediately with a fixed 12‐unit bridge. Materials and Methods: In total, 184 implants were installed in 36 patients:30 with healed bone and 6 with some remaining teeth, which were extracted simultaneously with implant installation. The provisional or final prostheses were installed 0 to 52 (mean 18.2) days later. Results: Thirteen of 184 (7.1%) implants failed within 3 months of loading in 5 of 36 (13.9%) patients:1 of 153 implants (0.7%) failed in healed bone, and 12 of 31 (39%) failed in fresh extraction sites. This consequently meant a loss of 3 of 36 (8.3%) prostheses, all in the extraction group. No implants were lost during 3 years of functional loading (16 patients, 75 implants). The average marginal bone level measured initially and after 1, 2, and 3 years was 0.8 mm (SD = 0.5), 1.0 mm (SD = 0.4), 1.1 mm (SD = 0.3), and 1.4 mm (SD = 0.5), respectively. Conclusions: Four to six Brånemark implants with nonroughened machined titanium surfaces can be loaded early or immediately with cross‐arch restorations in healed mandibulary bone, but this cannot be recommended for fresh extraction sites.
Ramus or Chin Grafts for Maxillary Sinus Inlay and Local Onlay Augmentation: Comparison of Donor Site Morbidity and Complications
Authors: Clavero Jaime , Lundgren Stefan 
Published: October 2006

ABSTRACT Background: The placement of endosseous implants in edentulous areas is frequently limited by inadequate bone volume of the residual ridge. Local bone grafts from the mandible are a convenient source of autogenous bone for alveolar reconstruction prior to implant placement. Purpose: The aim of the present study was to document and compare the morbidity and the frequency of complications occurring at two intraoral donor sites: the mandibular symphysis and the mandibular ramus. Material and Methods: This study reviewed 53 consecutively treated patients:29 with autogenous bone grafts from the mandibular symphysis and 24 with mandibular ramus bone grafts. Each patient received a questionnaire 18 months after surgery regarding problems that may have occurred during the postoperative period. Results: In the patients in whom bone was harvested from the mandibular ramus, there were fewer postoperative symptoms immediately after the operation than with mandibular symphysis harvesting. Twenty‐two of the 29 patients with symphysis grafts experienced decreased sensitivity in the skin innervated by the mental nerve 1 month after the operation. Five of the 24 patients with ramus grafts experienced decreased sensitivity in the vestibular mucosa corresponding to the innervation of the buccal nerve.Eighteen months after the surgery, 15 of the 29 patients in the symphysis group still had some decreased sensitivity and presented with permanent altered sensation. Only one of the patients grafted from the mandibular ramus presented with permanent altered sensation in the posterior vestibular area. No major complication occurred in the donor sites in any of the 53 patients. Conclusion: The results of this study favored the use of the ascending mandibular ramus as an intraoral donor site for bone grafting.