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Background/Introduction Recent evidence has confirmed low bleeding risk with double antithrombotic therapy, combining oral anticoagulant (OAC) and single platelet inhibitor, in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI). Among the Asian AF population, most of the patients received dual antiplatelet therapy (DAPT) without OACs, even after the introduction of non-vitamin K oral anticoagulants (NOACs). Purpose The current nationwide study assessed 3-month ischemic and bleeding risks of DAPT in comparison to triple antithrombotic therapy among the Korean AF population undergoing PCI. Methods We analyzed the claims records of 11,039 patients (mean age 70 years, 66.3% male, and mean CHA2DS2-VASc score 3.2) between 2013 to 2018. Patients were categorized into triple therapy group with vitamin K antagonists (VKAs-TT), or NOACs (NOACs-TT), and DAPT group according to the antithrombotic therapy after PCI. 3-month risks of ischemic stroke, non-fatal myocardial infarction, any in-hospital death, and major bleeding were compared between groups after baseline adjustment using inverse probability weighting. Results A total of 1,786, 1,997, and 7,256 patients were allocated to the VKAs-TT, NOACs-TT, and DAPT groups. The DAPT group had a higher prevalence of prior MI and coronary revascularization, but had lower thromboembolic and bleeding risks than the triple antithrombotic therapy groups (mean CHA2DS2-VASc score 3.8, 4.1, and 3.5; and mean HAS-BLED score 3.3, 3.4, and 3.1 for VKAs-TT, NOACs-TT, and DAPT groups, respectively). The NOACs-TT group was associated with a lower risk of ischemic stroke (hazard ratio [HR] 0.38, 95% confidence interval [CI] 0.20–0.70) and any in-hospital death (HR 0.70, 95% CI 0.49–0.98) compared with the VKAs-TT group. The DAPT group showed a lower risk of ischemic stroke (HR 0.41, 95% CI 0.27–0.63) and major bleeding (HR 0.55, 95% CI 0.37–0.84) than the VKAs-TT group, especially in patients without prior OAC treatment. The DAPT group showed a comparable ischemic risk against the NOACs-TT group, although the risk of major bleeding was lower in the DAPT group, especially among old age (HR 0.47, 95% CI 0.29–0.78) or OACs-naive patients (HR 0.50, 95% CI 0.29–0.86). Conclusion Among the Asian AF population, using short-term DAPT for 3-month after PCI was associated with a lower risk of bleeding without increasing ischemic risk compared to triple antithrombotic therapy with OAC. This may be a therapeutic option in very high bleeding risk patients who have had complex PCI necessitating focus on DAPT in the initial 3 month period. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): This study was supported by grant no 3020200200 from the Seoul National University Hospital Research Fund, by the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, Republic of Korea, the Ministry of Food and Drug Safety) (Project Number: 202013B14), and by the Korea National Research Foundation funded by the Ministry of Education, Science and Technology (grant 2020R1F1A106740). Figure 1Figure 2

Background In a recent study, alcohol abstinence reduced the atrial fibrillation (AF) recurrence in patients with AF. However, the relationship between alcohol consumption and incident stroke in patients with AF per se remains unclear. Purpose To evaluate the association between alcohol consumption status (and its changes) after newly diagnosed AF and the risk of ischaemic stroke. Methods Using the Korean nationwide claims and health examination database, we included subjects who were newly diagnosed with AF between 2010 and 2016. Patients were categorized into three groups according to the status of alcohol consumption before and after AF diagnosis: non-drinkers; abstainers from alcohol after AF diagnosis; and current drinkers. The primary outcome was incident ischaemic stroke during follow-up. Results Among a total of 97,869 newly diagnosed AF patients, 51% were non-drinkers, 13% were abstainers, and 36% were current drinkers. After inverse probability of treatment weighting, baseline characteristics of three groups were well-balanced. Compared to current drinkers, abstainers and non-drinkers were associated with a lower risk of ischaemic stroke (hazard ratio [HR] 0.86, 95% confidence interval [CI] 0.77–0.96 for abstainers and HR 0.75, 95% CI 0.70–0.81 for non-drinkers, respectively). Amongst current drinkers, there was a dose-response relationship between the amount of alcohol consumption and the risk of ischaemic stroke. Conclusion Current alcohol consumption was associated with an increased risk of ischaemic stroke in patients with newly diagnosed AF, and alcohol abstinence after AF diagnosis could reduce the risk of ischaemic stroke. Lifestyle intervention, including attention to alcohol consumption, should be encouraged as a part of a comprehensive approach to AF management to improve clinical outcomes. Funding Acknowledgement Type of funding sources: None.

Background In a recent trial, rivaroxaban monotherapy was noninferior for efficacy and superior for safety to rivaroxaban plus single antiplatelet therapy, as antithrombotic therapy for patients with atrial fibrillation (AF) and stable coronary artery disease (CAD). However, there are limited data regarding the comparative effectiveness and safety of oral anticoagulant (OAC) monotherapy versus OAC plus single antiplatelet therapy (SAPT) in real-world practice, especially after the introduction of direct oral anticoagulants (DOAC). Purpose To compare the effectiveness, safety, and net clinical benefit of OAC monotherapy to OAC plus SAPT in patients with AF and stable CAD of 1-year and 3-year after percutaneous coronary intervention (PCI) in a contemporary real-world observational cohort. Methods Using the Korean nationwide claims database, we included AF patients who underwent PCI from January 1, 2009 to February 28, 2019. Considering dynamic changes of antithrombotic therapy according to the period after receiving PCI, the index antithrombotic treatment was independently defined at the different time after receiving PCI and we conducted two cohort: 1-year and 3-year after PCI. In each cohort, the baseline characteristics of OAC monotherapy and OAC plus SAPT groups were balanced using inverse probability of treatment weighting (IPTW) methods. To assess clinical outcomes, ischemic stroke, myocardial infarction, major bleeding, and composite clinical outcomes of each outcome were analyzed. Results In cohort with 1-year after PCI, 678 patients with OAC monotherapy and 3159 patients with OAC plus SAPT were included. In cohort with 3-year after PCI, 1038 patients with OAC monotherapy and 2128 patients with OAC plus SAPT were enrolled. The baseline characteristics were well-balanced after IPTW between the two groups in both cohorts. Among total population, about 45% of patients prescribed DOAC as OAC treatment. Among patients with 1-year after PCI, OAC monotherapy and OAC plus SAPT showed comparable results for ischemic stroke, myocardial infarction, major bleeding, and composite clinical outcomes (Figure). In cohort with 3-year after PCI, OAC monotherapy and OAC plus SAPT showed comparable results for ischemic stroke and myocardial infarction, but OAC monotherapy was associated with a lower risk of the composite clinical outcome (hazard ratio [HR] 0.762, 95% confidence interval [CI] 0.607–0.950), mainly driven by reduction of major bleeding risk (HR 0.762, 95% CI 0.607–0.950) compared to OAC plus SAPT (Figure). Conclusion OAC monotherapy might be, at least, comparable choice for patients with AF and stable CAD compared to OAC plus SAPT. In patients with stable CAD more than 3-years after index PCI, OAC monotherapy could be better therapeutic choice to achieve less major bleeding and positive net clinical benefit. Funding Acknowledgement Type of funding sources: None.

BACKGROUND: Cardiovascular disease is one of the main causes of mortality in patients with chronic obstructive pulmonary disease (COPD), and atherosclerosis is a cause of cardiac comorbidities in COPD. However, it is not clear whether airflow limitation is associated with atherosclerosis irrespective of smoking.OBJECTIVE: To investigate whether airflow limitation is independently associated with vascular stiffness.METHODS: We enrolled 18 893 participants (male 70.5%; mean age 47.5 ± 9.8 years; never smokers 44.2%) who underwent spirometry and brachial-ankle pulse wave velocity (baPWV) as part of a standard health examination at Ajou University Hospital, Suwon, South Korea, from January 2010 to December 2015.We defined vascular peripheral atherosclerosis as baPWV ≥ 1400 cm/s and airflow limitation as pre-bronchodilator ratio of forced expiratory volume in 1 sec (FEV1) to forced vital capacity (FVC) RESULTS: Mean baPWV was higher in subjects with airflow limitation (1477.6 ± 331.7 cm/sec, n = 638) than in those without airflow limitation (1344.1 ± 231.8 cm/sec, n = 18255, P < 0.001). In multivariate logistic regression analysis, the following were independent predictors associated with peripheral atherosclerosis (P < 0.05): age, male sex, fasting serum glucose, mean blood pressure, serum leukocyte count, serum low density lipoprotein level and FEV1.CONCLUSION: Airflow limitation was an independent predictor of vascular stiffness irrespective of smoking history, which suggests that airflow limitation is linked with atherosclerosis.

Background Although the prescription of non-vitamin K antagonist oral anticoagulants (NOACs) in patients with non-valvular atrial fibrillation (AF) has been rapidly increasing in Asian countries since their introduction, limited evidence exists on the effectiveness and safety of warfarin and all 4 available NOACs from current clinical practice in the Asian population. We aimed to evaluate comparative effectiveness and safety of warfarin and all 4 available NOACs Methods We studied a retrospective observational cohort of oral anticoagulant (OAC) naïve non-valvular AF patients treated with warfarin or NOACs (rivaroxaban, dabigatran, apixaban, or edoxaban) from January 2015 to December 2017, based on the Korean Health Insurance Review and Assessment database. For the comparisons, warfarin to 4 NOACs and NOAC to NOAC comparison cohorts were balanced using inverse probability of treatment weighting (IPTW). Ischemic stroke, intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB), major bleeding (MB) and a composite clinical outcome were evaluated. Results A total of 116,804 patients were included (25,420 with warfarin, 35,965 with rivaroxaban, 17,745 with dabigatran, 22,177 with apixaban, and 15,496 with edoxaban). Patients treated with warfarin were younger (mean age 67 years) compared to NOAC users (71 to 73 years) and had lower mean CHA2DS2-VASc score (3.18) than the NOAC groups (3.58 to 3.76). Among the NOAC users, patients prescribed apixaban were older (mean age 73 years) than other NOAC groups (71 to 72 years), had higher mean CHA2DS2-VASc score (3.76) than others (3.55 to 3.63) and higher burden of comorbidities. More than half of patients were prescribed reduced dose regimes. After IPTW, all baseline covariates were well balanced across 5 treatment groups. Compared with warfarin, all NOACs were associated with lower risks of ischemic stroke, ICH, GIB, MB and composite outcome (Figure A). Apixaban and edoxaban showed a lower rate of ischemic stroke compared with rivaroxaban and dabigatran (Figure B). Apixaban, dabigatran and edoxaban had a lower rate of GIB and MB compared with rivaroxaban. The composite clinical outcome was non-significantly different for apixaban vs edoxaban. Conclusions In this large contemporary observational Asian cohort, all 4 NOACs were associated with lower rates of ischemic stroke and major bleeding compared to warfarin. Differences in clinical outcomes between NOACs may give useful guidance for physicians to choose drugs to fit their particular patient clinical profile.

Immediate breast reconstruction is safe from an oncological perspective, but the relatively high rate of postoperative complications raises oncological concerns. The present study aimed to evaluate the potential influence of postoperative complications after immediate breast reconstruction on breast cancer recurrence and survival.Patients with breast cancer who had total mastectomy and immediate reconstruction between 2008 and 2013 were followed for at least 5 years. The impact of postoperative complications on oncological outcomes was assessed using multivariable Cox regression analyses.In total, 438 patients with a median follow-up of 82 months were analysed. Five-year local recurrence-free, disease-free and overall survival rates were 95·4, 93·1 and 98·4 per cent respectively. Postoperative complications developed in the operated breast in 120 patients (27·4 per cent) and at other sites (flap donor) in 30 patients (6·8 per cent). Development of breast complications was associated with significantly increased rate of recurrence compared with no complications (16·7 versus 5·9 per cent; P = 0·002). In multivariable analysis, patients with breast complications had significantly worse disease-free survival than those with no complications (hazard ratio (HR) 2·25; P = 0·015). This remained significant in patients who received adjuvant therapy without delay (8 weeks or less after surgery) (HR 2·45; P = 0·034).Development of postoperative complications in the breast can have a negative impact on survival and recurrence after immediate reconstruction.La reconstrucción mamaria inmediata es una técnica segura desde el punto de vista oncológico, pero con una tasa relativamente alta de complicaciones postoperatorias, lo que preocupa por si puede afectar a los resultados. Este estudio tuvo como objetivo evaluar la influencia potencial de las complicaciones postoperatorias tras la reconstrucción mamaria inmediata en la recidiva y la supervivencia del cáncer de mama. MÉTODOS: Se hizo un seguimiento de al menos 5 años de las pacientes a las que se realizó una mastectomía total por cáncer de mama y una reconstrucción mamaria inmediata entre 2008 y 2013. Se evaluó el impacto de las complicaciones postoperatorias en los resultados oncológicos mediante un análisis multivariables de regresión de Cox.Se analizaron 438 pacientes con una mediana de seguimiento de 82 meses. La supervivencia libre de recidiva local a 5 años, la supervivencia libre de enfermedad y la supervivencia global fueron del 95,4%, 93,1% y 98,4%, respectivamente. Hubo complicaciones postoperatorias en la mama en 120 (31,8%) pacientes y en otros lugares (zona donante de colgajo) en 30 (6,8%). La presentación de complicaciones mamarias se asoció con una tasa de recidiva significativamente mayor en comparación con el grupo de pacientes sin complicaciones (16,7% versus 5,9%, P 0,01). En el análisis multivariable, las pacientes con complicaciones mamarias mostraron una supervivencia libre de enfermedad significativamente menor que aquellas que no padecieron complicaciones (cociente de riesgos instantáneos, hazard ratio, HR 2,25; P = 0,02). También fue significativo el porcentaje de pacientes que recibieron tratamiento adyuvantes sin demora (≤ 8 semanas después de la operación) (HR 2,45; P = 0,03). CONCLUSIÓN: El desarrollo de complicaciones postoperatorias en la mama puede impactar negativamente en la supervivencia y en la recidiva después de la reconstrucción inmediata.

We estimate the fractal dimension of the ρ Ophiuchus Molecular Cloud Complex, associated with star forming regions. We selected a cube (v, l, b) database, obtained with J = 1−0 transition lines of 12 CO and 13 CO at a resolution of 22′′ using a multibeam receiver system on the 14-m telescope of the Five College Radio Astronomy Observatory. Using a code developed within IRAF, we identified slice-clouds with two threshold temperatures to estimate the fractal dimension. With threshold temperatures of 2.25 K (3σ) and 3.75 K (5σ), the fractal dimension of the target cloud is estimated to be D = 1.52–1.54, where P ∝ A D/2 , which is larger than previous results. We suggest that the sampling rate (spatial resolution) of observed data must be an important parameter when estimating the fractal dimension, and that narrower or wider dispersion around an arbitrary fit line and the intercepts at NP = 100 should be checked whether they relate to rms noise level or characteristic structure of the target cloud. This issue could be investigated by analysing several high resolution databases with different quality (low or moderate sensitivity).

We investigated the electrocaloric (EC) effects in epitaxial Ba0.8Sr0.2TiO3 (BSTO) thin films grown on LaAlO3 and MgO substrates and in BSTO sol-gel thin films grown on Si substrates. We compared the EC effects in two forms of BSTO to confirm whether the giant EC effect recently observed in the polycrystalline thin film is an intrinsic effect or an extrinsic effect exclusively occurring in polycrystalline thin films with nano-sized grains. The EC effect in our BSTO single crystals exhibited a moderate EC temperature change over a broad temperature range. On the other hand, the EC effect in the BSTO sol-gel film was observed over a narrow temperature range with a giant ΔT of about 14 °C. We claim that this giant EC effect is due to the increased saturation field related to the small grain size in the sol-gel thin film.

Multiferroic systems fashioned by involvement of a ferroelectric phase and a ferromagnetic phase have received significant attention because of their wide possibilities for tailoring properties. However, many interrogations persist about how the structure and chemistry of interface mediates magnetodielectric activities. In this study, we have explored the magnetic, dielectric and magnetodielectric behavior of BaTiO3/Fe3O4 core/shell nanocomposite synthesized by combined co-precipitation cum sonochemical method. The phase formation of the core/shell naonocomposite was confirmed independently from X-ray diffraction and selected area electron diffraction studies. The microstructure of the sample was studied by transmission electron microscopy and High resolution TEM revealing a good mixing of two phases in the form of core (BaTiO3)/shell (Fe3O4). Magnetic property of the sample was investigated using a vibrating sample magnetometer (VSM) at room temperature. The magnetic study reveals that the synthesized core/shell nanocompositeis ferromagnetic with saturation magnetization of ~58 emu/g. The dielectric constant of the core/shell nanocomposite, measured as a function of temperature, at frequencies 1, 10, 100, 500 and 1 MHz combines almost the characteristics of BaTiO3 and Fe3O4 in accordance with the Maxwell–Garnett equation. However, near 125 K a clear hump is observed probably due to characteristic Verwey transition (TV) in Fe3O4. The dielectric constant also shows dispersion behavior with increasing frequency due to Maxwell–Wagner interfacial polarization. Furthermore, the shrinkagein dielectric constant (at 20 K) on the application of 1 T external magnetic field depicts the possible coupling between the dielectric (BaTiO3) and the magnetic (Fe3O4) phases of BaTiO3/Fe3O4 core/shell nanocomposite.

We present a multi-dimensional reduction method of the surveyed cube database obtained using a single-dish radio telescope in Taeduk Radio Astronomy Observatory (TRAO). The multibeam receiver system installed at the 14 m telescope in TRAO was not optimized at the initial stage, though it became more stabilized in the following season. We conducted a Galactic Plane survey using the multibeam receiver system. We show that the noise level of the first part of the survey was higher than expected, and a special reduction process seemed to be definitely required. Along with a brief review of classical methods, a multi-dimensional method of reduction is introduced; It is found that the ‘background’ task within IRAF (Image Reduction and Analysis Facility) can be applied to all three directions of the cube database. Various statistics of reduction results is tested using several IRAF tasks. The rms value of raw survey data is 0.241 K, and after primitive baseline subtraction and elimination of bad channel sections, the rms value turned out to be 0.210 K. After the one-dimensional reduction using ‘background’ task, the rms value is estimated to be 0.176 K. The average rms of the final reduced image is 0.137 K. Thus, the image quality is found to be improved about 43% using the new reduction method.

A test circuit for modular multilevel converter (MMC)-based voltage-sourced converter valves in high-voltage direct current (HVDC) system is dealt with. The proposed scheme has an ability to provide a submodule current having DC component as well as AC component to represent real operating condition of HVDC transmission system. There is no need of extra power supply to provide the DC current component because the scheme has inherent circulating DC current between rectifier and inverter valves. Therefore, only one small power rated DC power supply is necessary. Experiments are carried out to show the validity of the proposed test circuit.

It has been demonstrated that 5-HT(1A) receptors play an important role in the pathophysiology of schizophrenia. Because Gastrodia elata Bl (GE) modulates the serotonergic system, we examined whether GE could affect phencyclidine (PCP)-induced abnormal behavior in mice. Repeated treatment with PCP increased immobility time, while it decreased social interaction time and recognition memory. PCP-induced abnormal behaviors were significantly attenuated by GE, and these effects were comparable to those of 8-OH-DPAT, a 5-HT(1A) receptor agonist. Furthermore, GE-mediated effects were counteracted by WAY 100635, a 5-HT(1A) receptor antagonist. Our results suggest that the antipsychotic effects of GE are, at least in part, mediated via activation of 5-HT(1A) in mice.

This journal suppl. entitled: Abstracts of the 26th Annual Meeting of the European Society of Human Reproduction and Embryology, Rome, Italy, 27-30 June 2010

Increasing globalization has created tremendous opportunities and challenges for organizations and societies. Consequently, a broad range of information technologies to better support the collaboration of diverse, and increasingly distributed, sets of participants is ever more utilized. Arguably, the success of such technology-mediated collaboration is dependent upon the quality of each individual's contributions; however, although individuals' motivations to do their best could be significantly influenced by the design of a system's human–computer interface, this area has received little attention within the context of group collaboration environments. We fill this gap by integrating research from human–computer interaction, motivation, and technology-supported group work to theoretically derive mechanisms for increasing each individual's motivation within a collective setting. Specifically, we manipulate the interface of a computer-mediated idea generation system (a widely used collaboration tool) to enhance the system's motivational affordance, i.e., the system's properties that fulfill users' motivational needs. Results from two studies demonstrate that by embedding the theoretically derived mechanisms “providing feedback” and “designing for optimal challenge” into the collaboration environment, significant performance gains were realized. The results suggest that even slight manipulations of the human–computer interface can contribute significantly to the successful design of a wide variety of group collaboration environments.

A new synthetic method for the formation of uniform α-Fe2O3 nanoparticles was reported and their magnetic properties were investigated. The sonochemical synthesis and the subsequent take-off technique resulted in spherical shaped α-Fe2O3 nanoparticles with an average diameter of 60 nm. The temperature- and applied magnetic field-dependent magnetization of the α-Fe2O3 nanoparticles was explained by the sum of two contributions, i.e., the Morin transition and superparamagnetism, because the critical size for superparamagnetism was within the size variation of the nanoparticles.

We have investigated the role of the grain boundary on the resistive magnetodielectric property of polycrystalline γ-Fe2O3 through impedance spectroscopy measurements. Depending on the sample preparation temperature, the dielectric constant of γ-Fe2O3 is significantly different especially at low frequencies ( 200 K). The value of the magnetodielectric effect at a specific frequency and the resonance frequency for the maximized magnetodielectric effect are different, although polycrystalline γ-Fe2O3 samples show a quite similar magnetoresistance. Through the experimentally obtained resistance ratio between the grain and the grain boundary, we can reproduce the magnetodielectric curves based on the Maxwell–Wagner model and the measured magnetoresistance.

Partial Trisomy- 9q was observed in an infant with a multiple malformation syndrome who survived to 18 months. Cytogenetic investigations stimulated by the family history of similarly affected individuals revealed a translocation, t(9;16)(q32;q24), identifiable in four generations of the proband's family. A review of our cases with those reported in the literature reveals clinical similarities. This report sets forth a clinical description of the characteristic phenotype of the 9q partial Trisomy syndrome, including findings at post-mortem, documents multigeneration transmission and discusses this syndrome's clinical overlap with other malformation syndromes.

CdTe thin films were grown on GaAs(100) substrates by using molecular beam epitaxy at various temperatures. The results of the X-ray diffraction (XRD) patterns showed that the orientation of the grown CdTe thin films was the (100) orientation. XRD patterns, atomic force microscopy images, high-resolution transmission electron microscopy (HRTEM) images, and photoluminescence spectra showed that the crystallinity of CdTe(100) epilayers grown on GaAs(100) substrates was improved by increasing the substrate temperature. HRTEM images showed that misfit dislocations existed at the CdTe/GaAs heterointerface. These results can help improve understanding of the substrate temperature effect on the structural and the optical properties of CdTe(100)/GaAs(100) heterostructures.

Real-time ultrasound-guided infraclavicular proximal axillary venous catheterization is used in many clinical situations and provides the advantages of catheter stabilization, a reduced risk of catheter-related infection, and comfort for the patient without limitation of movement. However, unintended catheter tip dislocation and accidental arterial puncture occur occasionally. This study was designed to investigate the influence of arm position on catheter placement and complications.Patients were randomized to either the neutral group (n=240) or the abduction group (n=241). In the neutral group, patients were positioned with the head and shoulders placed in an anatomically neutral position and the arms kept by the side during catheterization. In the abduction group, the right upper arm was abducted at 90° from the trunk during catheterization. After real-time ultrasound-guided catheterization was carried out in the right infraclavicular proximal axillary vein, misplacement of the catheter and all complications were evaluated with ultrasound and chest radiography.The success rate of complete catheterization before evaluating the placement of the catheter was high in both groups (97.1 vs 98.8%, P=not significant). The incidence of accidental arterial puncture was not different (1.7 vs 0%, P=not significant). The incidence of misplacement of the catheter was higher in the neutral group than in the abduction group (3.9 vs 0.4%, P=0.01). There were no complications, such as haemothorax, pneumothorax, or injury to the brachial plexus and phrenic nerve, in either group.Upper arm abduction may minimize the risk of misplacement of the catheter during real-time ultrasound-guided infraclavicular proximal axillary venous catheterization.The trial was registered with the Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp. Identifier: KCT0001417.

In Korea, a speed up test of a train was performed on a high speed railway. The name of the vehicle is HEMU-430x. While the train increased speed from 300km/h to 421km/h on a railway track designed for 350km/h, elastic vertical displacement was measured on the transition zone of bridge-earth in the Gaya overpass bridge. Until the train speed reached 421km/h, the maximum of elastic vertical displacement measured 0.061mm on top of a reinforced roadbed and 0.311mm on top of a HSB (hydraulic stabilized base). Maximum vertical displacement of HSB measured at 383km/h, displacement decreased over 383km/h. Vertical displacement of reinforced roadbed increased according to the increase in train speed.

Optical conductivity spectra of a cleaved ab plane of ${\mathrm{La}}_{1.2}{\mathrm{Sr}}_{1.8}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}$ exhibit a small polaron absorption band in the midinfrared region over all temperatures. With decreasing temperature $(T)$ up to Curie temperature ${(T}_{C}),$ the small polaron band moves to a higher frequency, resulting in a finite gaplike feature. However, it shifts to a lower frequency below ${T}_{C}.$ With decreasing T, a stretching phonon mode hardens above ${T}_{C}$ and softens below ${T}_{C}.$ These concurring changes of lattice and electronic structure indicate that short-range polaron correlation exists above ${T}_{C}$ but disappears with the magnetic ordering.

Magnetic-field $(H)$-dependent optical conductivity spectra $\ensuremath{\sigma}(\ensuremath{\omega})$ and dielectric constant spectra $\ensuremath{\varepsilon}(\ensuremath{\omega})$ of a layered antiferromagnet $(A\ensuremath{-}\mathrm{t}\mathrm{y}\mathrm{p}\mathrm{e})$ ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}$ were presented. At 0.0 T in 4.2 K, the $\ensuremath{\sigma}(\ensuremath{\omega})$ showed a small Drude-like peak in the far-infrared region and a broad absorption peak in the mid-infrared region. As H increased, large spectral weights were transferred from high- to low-energy regions with increase of the Drude-like peak. We found that a polaron picture could explain most of the H-dependent spectral changes. By analyzing the H-dependent spectral weight changes and $\ensuremath{\varepsilon}(\ensuremath{\omega}),$ we showed that a dimensional crossover from a two-dimensional to a three-dimensional metal could occur in ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}.$

Various zinc dicarboxylate catalysts were synthesized by the reaction of zinc oxide with eleven different glutaric acid derivatives, and their coordination characteristics were investigated by infrared spectroscopy. The electronic nature and steric hinderance of substituents influenced the coordination of the carboxylate and the zinc metal ion. The coordination characteristics were classified into three categories: (i) compounds exhibiting bridging bidentate coordinating bonding modes, such as syn-anti and syn-syn bridging; (ii) compounds with only unidentate coordination; and (iii) compounds with mixed coordinations of unidentate and bridging bidentate. All the zinc carboxylate catalysts produced poly(propylene carbonate)s (PPCs) by the copolymerization of carbon dioxide and propylene oxide. The first category of catalysts produced relatively higher yields than the other categories. Zinc glutarate without any substituent, which is a catalyst in the first category, produced PPC with the highest yield and the highest molecular weight. The catalytic activity of zinc glutarate was suppressed by incorporation of substituents. The suppression of the catalytic activity might be due to the variation in the Lewis acidity of the zinc site as well as changes in the morphological structure caused by the substituents. Methylaluminoxane was also evaluated as a catalyst for the copolymerization, but it produced copolymers containing a large amount of ether linkages.

Temperature and polarization dependent electronic structure of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ was investigated by optical conductivity analyses. With decreasing temperature, a broad midinfrared peak in the optical conductivity for $E\ensuremath{\Vert}\mathrm{ab}$ of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ becomes narrower and shifts toward a higher frequency, and, furthermore, its optical gap significantly increases. We showed that such a temperature-dependent behavior of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ is the result of cooperative enhancement of the orbital ordering stabilized by the CE-type magnetic ordering and the Jahn-Teller distortion.

We report the exchange bias in antiferromagnet/ferrimagnet Cr₂O₃/Fe₃O₄ core/shell nanoparticles. The magnetic field hysteresis curve for Cr₂O₃/Fe₃O₄ nanoparticles after field-cooling (FC) clearly showed both horizontal (H EB ~610 Oe) and vertical (ΔM~5.6 emu/g) shifts at 5 K. These shifts disappeared as the temperature increased toward the Neel temperature of Cr₂O₃ (T N ~307 K). The H EB and ΔM values were sharply decreased between the 1 s t and the 2 nd magnetic field cycles, and then slowly decreased with further cycling. These results are discussed in terms of the formation of single domains with pinned, uncompensated, antiferromagnetic spin and their evolution into multi-domains with cycling.

A resonant photoemission study has been performed for Pr{sub 1{minus}x}Sr{sub x}MnO{sub 3}thinsp(x=1/3,1/2) and the partial spectral weight (PSW) distributions of both Pr 4f and Mn 3d electrons have been determined. With varying temperature ({ital T}) and {ital x}, metal-insulator transitions are observed in the photoemission data. The Pr ions in Pr{sub 1{minus}x}Sr{sub x}MnO{sub 3} are trivalent, and Pr 4f PSW exhibits a dominant hybridization peak indicating large Pr 4f{minus}Othinsp2p mixing. The Mn 3d PSW at low {ital T} shows a charge gap for x=1/2, and a reduced spectral intensity near E{sub F} for x=1/3, suggesting the localized nature due to the lattice polaron formation. thinsp {copyright} {ital 1999} {ital The American Physical Society}

We have mapped a 17 square-degree section () = () of the Galactic Anticenter region in the 12 CO line using the 3-mm SIS receiver on the 14-m telescope at the Taeduk Radio Astronomy Observatory. A total of 7 000 spectra has been obtained with a grid spacing of . The results of the observations are presented in the form of and contour maps. Molecular emission of the mapped area is found to be very extended and matches with the FIR emission boundary. The radial velocity of the molecular gas is found to be within the range of +10 km s -1 . We also found several small clouds located at , having km s -1 , which is quite anomalous in this direction. We identified 30 individual clouds within the mapped region with an arbitrary threshold temperature using a cloud identification code. Twelve subclouds were also identified from the largest cloud with a higher threshold temperature. The ratio of dust emission to CO integrated intensity for the Galactic Anticenter region is found to be similar to that of the dark clouds in solar neighborhood, and much less than that of giant molecular clouds, implying that the heating source within the clouds is minimal.

We investigated temperature-dependent optical conductivity spectra of ${\mathrm{La}}_{7/8}{\mathrm{Sr}}_{1/8}{\mathrm{MnO}}_{3}.$ Its phonon bending mode starts to be splitted near a structural phase-transition temperature. With further cooling, the strength of a midinfrared small polaron peak, which is located at 0.4 eV, becomes increased. These temperature-dependent changes in the phonon spectra and the polaron absorption peaks were explained by a phase separation and a percolation-type transition.