bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical properties of anthracene‐fluorene mixed crystals fabricated by cell method
Authors: Aoki‐Matsumoto Tamao , Takama Atsushi , Mizuno Ken‐ichi , Hirai Takeshi , Matsumura Michio 
Published: September 2008

AbstractAnthracene‐fluorene mixed crystals with anthracene mole fraction of 0.1 to 100% are fabricated using a cell method and their optical properties are studied. In contrast to sharp luminescence due to isolated anthracene molecules in a 0.1% doped sample and in a pure anthracene bulk crystal, broad luminescence bands are observed in the middle concentration samples. For samples with less than 50% anthracene, broad luminescence bands are attributable to localized excited state at anthracene molecule pair which is accompanied by lattice relaxation. For samples with higher anthracene concentration, observed broad luminescence has lower peak energy than that of an anthracene bulk crystal. Origin of the luminescence is proposed to be excitation localized at fluorene impurity induced X‐traps in anthracene clusters. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lattice‐mismatch‐strain effects on excitons in GaAs1–xNx /GaAs heterostructures
Authors: Hashimoto Jun , Nakayama Masaaki 
Published: September 2008

AbstractWe have investigated the lattice‐mismatch‐strain effect on excitons in GaAs1‐x Nx (500 nm)/GaAs heterostructures with x = 0.4, 0.8, and 1.5% grown on a GaAs substrate using photoreflectance spectroscopy that is sensitive to excitonic transitions. It is found that the heavy‐hole (HH) and light‐hole (LH) excitons of the GaAs1‐x Nx layer, which are degenerate in a bulk crystal, are split and that the energy of the LH exciton is lower than that of the HH exciton. In this case, a quantum‐size effect is negligible because the GaAs1‐x Nx layer thickness is sufficiently thick. The HH‐LH splitting energy increases with an increase of nitrogen concentration (x) in addition to a drastic decrease of the energies of the HH and LH excitons. We have quantitatively analyzed the nitrogen‐concentration dependence of the energies of the HH and LH excitons, taking account of the lattice‐mismatch‐strain effect on the band structure and nitrogen‐induced giant bowing of the band‐gap energy. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural and electronic properties of Co‐doped ZnO nanocrystals synthesized by co‐precipitation method
Authors: Hasuike Noriyuki , Nishio Koji , Isshiki Toshiyuki , Kisoda Kenji , Harima Hiroshi 
Published: September 2008

AbstractZnO nanocrystals doped with Co were synthesized by co‐precipitation method combined with post‐thermal treatment. The synthesized crystals formed high‐quality wurtzite ZnO crystal lattice with the dimension about 10 nm, substituting Co ions into Zn sites in the composition range of [Co] < 3.0%. The position of Co2+/1+ charge transfer (CT) level composed by O 2p and Co 3d orbitals was observed at 3.0 eV by optical absorption measurements. Raman spectra showed the enhancement of LO phonon due to resonant Raman effect caused by photo‐excitation of free carriers mediated the CT level. And, Photoluminescence spectra showed UV emission at ∼3.3 eV suppressed and shifted to higher energy side with increase in Co doping level, indicating increase in nonradiative recombination centers and the possibility of band‐gap engineering in Zn1–xCoxO nanocrystals, respectively. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Lost of coherence due to disorder in molecular rings
Authors: Heřman Pavel , Zapletal David , Barvík Ivan 
Published: September 2008

AbstractThe time dependence of the anisotropy of fluorescence can indicate the coherent exciton transfer regime.We are comparing time development of this quantity after an impulsive excitation obtained for the ring models of bacterial antenna complexes with tangential and radial optical transition dipole moments arrangement as in nonameric LH2 and octameric LH4 units.We compare its decay for three models of uncorrelated static Gaussian disorder: in the local exciton energies, in transfer integrals and in radial positions of molecules. Dynamic disorder is taken into account simultaneously using a Markovian treatment of the interaction with the bath. The influence of dimerization in molecular local energies, the strength of dynamic disorder and the shape of spectral density on difference of the anisotropy of fluorescence is shown and discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gain‐narrowed emissions of thiophene/phenylene co‐oligomer single crystals
Authors: Hiramatsu Toru , Matsuoka Naoki , Yanagi Hisao , Sasaki Fumio , Hotta Shu 
Published: September 2008

AbstractIn order to elucidate the origin of gain‐narrowed photoluminescence spectra of 5,5″‐bis(4‐biphenylyl)‐2,2′:5′,2″‐terthiophene (BP3T) single crystals, the dependence of excitation energy threshold on excitation lengths was studied at 12 K. The emission peak of the 0‐1 vibrational band was narrowed at a constant excitation density irrespective of the excitation length, indicating that the gain‐narrowing followed a stimulated emission process. On the other hand, the excitation density threshold for the 0‐2 peak decreased with increasing excitation length. The latter behaviour is suggestive of a cooperative interaction among uniaxially oriented transition dipoles in the BP3T crystal. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence properties of annealed InAs quantum dots capped by InGaAs layers
Authors: Hiratsuka Shingo , Saravanan Shanugam , Harayama Takahisa , Ohtani Naoki 
Published: September 2008

AbstractWe have investigated the annealing‐temperature dependence on photoluminescence (PL) properties of InAs quantum dots (QDs) fabricated on GaAs substrate. The annealing temperatures were varied from 700 to 1000 °C. The observed PL spectra were drastically changed by changing the annealing temperature. The PL peaking‐wavelength of non‐annealed sample is around 1200 nm. However, the peaking‐wavelength is drastically blue‐shifted with increasing annealing temperature. The strongest PL intensity is observed from the sample annealed at 875 °C. This PL intensity is more than seven fold compared with that of the non‐annealed sample. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theory of nano optical manipulation by designed light fields under excitonic resonance conditions
Authors: Iida Takuya , Yoshimizu Takashi , Ishihara Hajime 
Published: September 2008

AbstractWe theoretically study the resonant radiation force on a nanoparticle confining an exciton under the irradiation of various light sources that consist of Laguerre‐Gaussian beams (LGB) with doughnut‐shaped intensity distribution on a beam cross‐section and optical orbital angular momentum (OAM) around light axis. As a result, we have clarified possibilities of novel types of nano optical manipulation as follows: (A) Size‐selective control of rotational motion of nano‐objects can be realized by changing light frequency near the exciton resonance in multiple optical potential wells in a standing wave field composed of counter‐propagating LGBs with the same OAM. (B) Spiral‐shaped optical traps can be formed by the combination of LGBs with different OAMs. Obtained results will drastically expand the degrees of freedom of resonant nano optical manipulation by incorporating the control technique of the rotational motion in addition to those of the translational and the relative motions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Four‐wave‐mixing study of exciton fine structure in GaN
Authors: Ishiguro T. , Toda Y. , Adachi S. , Tadatomo K. , Hoshino K. 
Published: September 2008

AbstractDephasing dynamics of exciton fine structure (EFS) caused by long and short range exchange interactions in GaN was investigated by using a four‐wave‐mixing (FWM) spectroscopy. The type of exchange interactions was selected by samples (uniaxially strained c ‐plane GaN films and a thick bulk GaN) and their geometries in optical excitation. Since each component of EFS is highly polarized, the polarization‐dependent FWM spectra successfully resolve the dephasing dynamics in the individual EFS resonances. The results show a difference in dephasing time, suggesting a contribution of anisotropic exchange interaction (AEI). (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
In‐situ X‐ray diffraction of mechanically milled β‐Al3Mg2 powders
Authors: Scudino S. , Sakaliyska M. , Stoica M. , Surreddi K. B. , Ali F. , Vaughan G. , Yavari A. R. , Eckert J. 
Published: September 2008

AbstractThe structure evolution during heating of mechanically milled single‐phase β‐Al3Mg2 has been investigated by in‐situ X‐ray diffraction. The nanoscale supersaturated Al(Mg) solid solution formed during milling transforms back to the original β‐Al3Mg2 phase through a sequence of phase transformations. At low temperatures, an increasing amount of Mg is rejected from the solid solution with increasing temperature. At intermediate temperatures, the β′‐phase, a hexagonal phase with approximate composition Al3Mg2, forms. Finally, at higher temperatures the original β‐Al3Mg2 phase is restored, indicating that the formation of the supersaturated solid solution during milling can be reversed by appropriate heat treatment. The phase transformations during heating are gradual and the temperature ranges of stability of the different structure configurations are quite large, all exceeding 50 K. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hypothesis testing in an errors‐in‐variables model with heteroscedastic measurement errors
Authors: de Castro Mário , Galea Manuel , Bolfarine Heleno 
Published: September 2008

AbstractIn many epidemiological studies it is common to resort to regression models relating incidence of a disease and its risk factors. The main goal of this paper is to consider inference on such models with error‐prone observations and variances of the measurement errors changing across observations. We suppose that the observations follow a bivariate normal distribution and the measurement errors are normally distributed. Aggregate data allow the estimation of the error variances. Maximum likelihood estimates are computed numerically via the EM algorithm. Consistent estimation of the asymptotic variance of the maximum likelihood estimators is also discussed. Test statistics are proposed for testing hypotheses of interest. Further, we implement a simple graphical device that enables an assessment of the model's goodness of fit. Results of simulations concerning the properties of the test statistics are reported. The approach is illustrated with data from the WHO MONICA Project on cardiovascular disease. Copyright © 2008 John Wiley & Sons, Ltd.
The coupled dynamics of human socio‐economic choice and lake water system: the interaction of two sources of nonlinearity
Authors: Suzuki Yukari , Iwasa Yoh 
Published: September 2008

AbstractWe study a mathematical model for the coupled dynamics of human socio‐economic choice and lake water system. In the model, many players choose one of the two options: a cooperative and costly option with low phosphorus discharge, and an economical option with high phosphorus discharge. The choice is affected by an economic cost, a social concern about water pollution, and a conformist tendency. The pollution level in the lake is determined by total phosphorus discharge by the players, the sedimentation and the outflow of phosphorus, and the recycling of phosphorus from the sediment. The model has two sources of nonlinearity: the cooperation level tends to be bistable due to conformist tendency of people (social hysteresis) and pollution level tends to be bistable because phosphorus recycling occurs faster in more eutrophic lakes (ecological hysteresis). The combination of these two sources may cause multiple stable equilibria or oscillations with a long periodicity. Small economic cost and strong social concern about pollution level can decrease the pollution level, but may not be very effective in enhancing the cooperation level. In contrast, strong conformist tendency produces a stable state with a high cooperation level and a low pollution level. We discuss implications of these results to the water quality management.
An In‐vitro Investigation of Selected Biological Activities of Hydrolysed Flaxseed (Linum usitatissimum L.) Proteins
Authors: Marambe P. W. M. L. H. K. , Shand P. J. , Wanasundara J. P. D. 
Published: September 2008

AbstractA study was conducted to determine bioactivities of flaxseed (Linum usitatissimum L.; variety: Valour) proteins and their hydrolysates. Isolated flaxseed proteins were treated with Flavourzyme® at different levels of enzyme to substrate ratio (E/S) and hydrolysis time. The unhydrolysed proteins and hydrolysates were studied for angiotensin I‐converting enzyme inhibiting (ACEI) activity, hydroxyl radical (OH·) scavenging activity and bile acid binding ability. Flavourzyme catalysed hydrolysis generated hydrolysates with a 11.94–70.62% degree of hydrolysis (DH). The hydrolysates (0.67 mg/ml) had strong ACEI activity (71.59–88.29%). The maximum ACEI activity containing hydrolysate exhibited an IC50 of 0.07 mg/ml (E/S: 1.5; Time: 12 h; DH: 11.94%). The OH· scavenging activity of the hydrolysates (0.5 mg/ml) was 12.48–22.08% with an IC50 of 1.56 mg/ml in the sample possessing maximum activity (E/S: 47.5; Time 0.7 h; DH: 24.63%). Both these activities were greater in hydrolysates with lower DH and higher peptide chain length (PCL) than those with higher DH and lower PCL. Hydrolysed flaxseed proteins (0.67 mg/ml) had no bile acid binding ability. The unhydrolysed proteins had no ACEI or OH· scavenging activity but demonstrated bile acid binding ability.
Metacognitive Therapy: Cognition Applied To Regulating Cognition
Authors: Wells Adrian 
Published: September 2008

AbstractThe theory and principles of Metacognitive therapy (MCT) are described and data supporting its effects are summarized. MCT does not advocate challenging of negative automatic thoughts or traditional schemas. It proposes the existence of a universal maladaptive thinking style that causes disorder and focuses on helping patients regulate their cognition more adaptively. It aims to reduce worry and rumination and alter problematic patterns of attention and coping. In doing so it targets underlying metacognition that controls thinking and helps patients develop new ways of consciously experiencing inner events. Data from treatment studies suggest that individual MCT techniques and full treatment are highly effective. Further randomized trials are clearly warranted.
Treatment of Alzheimer's Disease with Anti-Homocysteic acid Antibody
Authors: Hasegawa Tohru , Mikoda Nobuyuki , Kitazawa Masashi , LaFerla Frank 
Published: September 2008

AbstractHomocysteic acid (HA) may play an important role in Alzhiemer disease (AD) as we previously reported that HA induced accumulation of intraneuronal A[beta]42. In this study, we first analyzed HA levels in a mouse model of AD. 4-month old pre-pathologic 3xTg-AD mice exhibited higher levels of HA in the hippocampus as compared to age-matched nontransgenic, suggesting that HA accumulation may precede both A[beta] and tau pathologies. To further determine the pathogenic role of HA in AD, we treated young 3xTg-AD mice with vitamin B6-deficient food for 3 weeks to induce the production of HA in the brain. Concominantly, mice received either saline or anti-HA antibody intraventricularly using a guide cannula every 3 days. Mice received anti-HA antibody significantly rescued cognitive impairment induced by vitamin B6 deficiency. Pathologically, 3-week treatment with vitamin B-6 deficient food resulted in strong neurodegeneration in the hippocampal CA1 zone and decreased hippocampal volume. In contrast, anti-HA antibody treatment attenuated these pathological changes. Taken together, we conclude that increased brain HA triggers memory impairment whose condition was deteriorated by amyloid and subsequent neurodegeneration and reduction of neurogenesis. Our results indicate a pathogenic role of HA in AD.
Attitudes towards the doctor–patient relationship: a prospective study in an Asian medical school
Authors: Lee Kheng Hock , Seow Adeline , Luo Nan , Koh David 
Published: September 2008

Context  Patient‐centredness is an accepted guiding principle for health system reform, patient care and medical education. Although these attitudes are strongly linked with cultural values, few studies have examined attitudes towards patient‐centredness in a cross‐cultural setting.Objectives  This prospective study evaluated attitudes towards patient‐centredness in a cohort of Asian medical students and examined changes in these attitudes in the same students on completion of their junior clinical clerkships.Methods  The study was conducted in a cohort of 228 medical students entering Year 3 in medical school. The Patient–Practitioner Orientation Scale (PPOS), a validated instrument which scores an individual’s level of patient‐centredness, was used.Results  Being female and having personal experience of continuing care were significantly associated with higher scores. Students in the USA were previously reported to have similar ‘caring’ but higher ‘sharing’ scores on the same scale. At the end of the junior clinical clerkship, there were improvements in the ‘caring’ subscale, but no change or a reduction in ‘sharing’. Students who did not have previous personal experience with continuing care experienced a greater increase in overall PPOS score.Conclusions  When compared with students in the USA, the students in our study appear to have a lower propensity to view the doctor–patient relationship as a partnership. This may be a reflection of differences in cultural norms and expectations of doctor–patient interaction in different societies. Our finding that attitudes towards patient‐centredness did not decline over the course of the year, which contrasts with findings of other studies, may be attributed to various factors and warrants further study.
Impairment of exploratory eye movement in schizophrenia patients and their siblings
Authors: Takahashi Sakae , Tanabe Eiichi , Yara Kazuo , Matsuura Masato , Matsushima Eisuke , Kojima Takuya 
Published: September 2008

Aims:  Previous family, adoption and twin studies of schizophrenia have shown that genetic factors contribute significantly to the risk of schizophrenia. The aim of the present study was therefore to investigate whether exploratory eye movement (EEM) abnormalities are related to the genetic markers linked to schizophrenia.Methods:  Twenty‐three probands with schizophrenia, 23 of their healthy siblings (23 proband–sibling pairs), and 43 unrelated normal controls performed EEM tasks. Two parameters were measured: (i) number of eye fixations in responsive search (NEFRS) and (ii) responsive search score (RSS).Results:  Abnormalities in NEFRS and RSS were more frequent in schizophrenia probands than in their unaffected siblings and in normal controls, and were also more frequent in the healthy siblings than in normal controls. Thus, the EEM test performances of the healthy siblings were intermediate between those of the probands with schizophrenia and those of normal controls.Conclusion:  Abnormalities of the EEM test parameters may be related to the genetic etiology of schizophrenia. The use of EEM parameters as an endophenotype for schizophrenia may facilitate linkage and association studies in schizophrenia.
Profiles associated with treatment retention in Japanese patients with methamphetamine use disorder: Preliminary survey
Authors: Kobayashi Ohji , Matsumoto Toshihiko , Otsuki Masaki , Endo Keiko , Okudaira Kenichi , Wada Kiyoshi , Hirayasu Yoshio 
Published: September 2008

Aims:  To identify profiles associated with treatment retention in Japanese patients with methamphetamine use disorder.Methods:  The study used a retrospective design based on clinical records. The subjects were 101 patients at the Kanagawa Psychiatric Center, Serigaya Hospital, who were diagnosed as having methamphetamine use disorder. They were divided in two groups, namely those who remained in treatment 3 months after the initial assessment, and those who did not. The primary analysis compared patient profiles between the two groups to detect discriminating variables, which were then submitted for secondary analysis using logistic regression to determine the most relevant predictor of retention.Results:  Primary analysis indicated that older age, having psychotic symptoms, receiving public assistance, and history of incarceration were associated with treatment retention after 3 months. Secondary analysis showed that positive history of incarceration was the most significant predictor of the outcome.Conclusions:  History of incarceration had the most significant treatment‐retention effect on Japanese patients with methamphetamine use disorder. The development and introduction of integrated programs that link methamphetamine‐dependent offenders to drug treatment is recommended in outpatient treatment for Japanese patients with methamphetamine user disorder.
Pharmacokinetic interaction between tandospirone and fluvoxamine in the rat contextual conditioned fear stress model and its functional consequence: Involvement of cytochrome P450 3A4
Authors: Nishikawa Hiroyuki , Inoue Takeshi , Masui Takuya , Izumi Takeshi , Nakagawa Shin , Koyama Tsukasa 
Published: September 2008

Aims:  In a previous study it was demonstrated that the anxiolytic action of tandospirone, a 5‐hydroxytryptamine (5‐HT)1A receptor agonist, is facilitated by cytochrome P450 (CYP) 3A4 inhibitors, such as ketoconazole and cimetidine. It is also known that fluvoxamine, a selective serotonin re‐uptake inhibitor (SSRI), inhibits CYP3A4. The purpose of the present study was to clarify the pharmacokinetic interaction between tandospirone and fluvoxamine and to evaluate their combined effect in the rat anxiety model.Methods:  The anxiolytic action of co‐administration of tandospirone and fluvoxamine was examined using the rat contextual conditioned fear stress model. After testing the conditioned fear, plasma concentrations of tandospirone and its major metabolite 1‐(2‐pyrimidyl) piperazine were determined.Results:  One day after fear conditioning, both tandospirone (60 mg/kg, p.o.) and fluvoxamine (60 mg/kg, p.o.) significantly inhibited conditioned freezing and their combination effect was additive. In addition, plasma concentration of tandospirone was increased by fluvoxamine.Conclusions:  There is a CYP3A4‐related drug–drug interaction between tandospirone and fluvoxamine. Therefore, fluvoxamine may facilitate the anxiolytic effect of tandospirone via CYP3A4 inhibition.