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Frank D. Graham (1890–1949) presented an innovative multi-country, multi-commodity trade model that attached great importance to link commodities and quantity adjustments, not perfect specializations and price adjustments as emphasized by John Stuart Mill and Alfred Marshall. However, due to some shortcomings, this model was not sufficiently understood and has been forgotten. This study reconstructs Graham’s theory of international values by rectifying the shortcomings. Through this reconstruction, the following is clarified. First, in multi-country, multi-commodity trade models, the existence of link commodities is general and perfect specializations seldom appear; therefore, quantity adjustments are normally performed in the face of demand shifts. Second, notwithstanding unchanging sectoral productivity at a national level, national wage rates can vary greatly according to the patterns of the international division of labor. Third, while the domestic relative wage rate increases with an increase in a home country’s productivity of link commodities, it does not increase with an increase in the productivity of commodities produced only in the home country.
To examine whether the issue and dissemination of national guidelines in the Manual of Antimicrobial Stewardship had an impact on reducing antibiotic use for acute respiratory tract infection (ARTI) and gastroenteritis.
Method:
An interrupted time-series analysis was performed using a large nationwide database from June 2016 to June 2018. Outpatients with ARTI or gastroenteritis aged ≥6 years were identified. The outcome measures were any antibiotic use and broad-spectrum antibiotic use. The season-adjusted changes in the rate of antibiotic prescriptions for 2 periods before and after the guideline issue date were examined.
Results:
There were 13,177,735 patients with ARTI and 300,565 patients with gastroenteritis during the study period. Among patients with ARTI, there was a significant downward trend in antibiotic use during the 2-year study period (−0.06% per week; 95% CI, −0.07% to −0.04%). However, there was no significant change in trends of antibiotic use between the pre-issue period and post-issue period (trend difference, −0.01% per week; 95% CI, −0.10% to 0.07%). Similarly, for patients with gastroenteritis, there was no significant change in the trends of antibiotic use between the pre-issue period and post-issue period (trend difference, −0.02% per week; 95% CI, −0.04% to 0.01%). Similar associations were observed in analyses for broad-spectrum antibiotic use.
Conclusions:
Despite the issue of national guidelines to promote the appropriate use of antibiotics, there were no significant changes in trends of antibiotic use for outpatients with ARTI or gastroenteritis between the pre-issue and post-issue periods.
Magnetic/fluorescent (magnetofluorescent) materials have become one of the most important tools in the imaging modality in vivo using magnetic resonance imaging (MRI) and fluorescence imaging. We succeeded in fabricating magnetofluorescent nanoparticles (MFNPs) consisting of silicon/magnetite composite nanoparticles. Our unique synthetic approach can control simultaneously the magnetic and fluorescence behaviors by varying the particle size, demonstrating the superparamagnetic behavior and green fluorescence for the MFNPs having mean diameter of 3.0 nm, and the ferromagnetic behavior without fluorescence for the MFNPs having mean diameter more than 5.0 nm. More intriguingly, the MFNPs with superparamagnetism can detect green fluorescence even after the magnetic guidance of MFNPs by the commercial neodymium magnet. Additionally, the MFNPs having two magnetic behaviors also possess good biocompatibility.
Galactic-scale studies of γ-rays and sub-mm radiation suggest that a significant amount of neutral interstellar medium is not detectable either in CO or HI (Grenier et al. 2005; Ade et al. 2011). This component is called “dark gas”. Here we argue that cool and dense atomic gas without molecules is responsible for the dark gas. This interpretation is supported by a recent finding of cool HI gas corresponding to the TeV γ-ray shell in the SNR RX J1713.7-3946 (Fukui et al. 2011). Such HI gas is not recognized under a usual assumption of optically thin HI emission but is identified by a careful analysis considering optically thick HI. The typical column density of such HI gas is a few times 1021 cm−2 and is also identified as visual extinction.
Organic thin-film transistors (OTFTs) using cross-linked olefin polymer as a gate insulator were fabricated on a plastic film. An olefin polymer layer was formed by spin-coating and baking at temperatures below 150°C. Pentacene was used as an organic semiconductor layer. The fabricated OTFTs with a short 5-μm-long channel showed a mobility of 0.1-0.2 cm2/Vs and a current ON/OFF ratio of 107. These OTFTs also exhibited good stable performance in the atmosphere. On the basis of the results, we fabricated a 5 inches OTFT-driven flexible active-matrix organic light emitting diode (AMOLED) display. The gate insulator, some metal wirings and electrodes on the OTFT backplane were formed on the plastic film by photolithography. After fabrication of the OTFT backplane, OLED layers were formed by vacuum deposition through a shadow-mask. Clear color moving images were observed on the flexible display even when it was bent.
We have demonstrated a 5-inch flexible color liquid crystal display (LCD) and organic light emitting display (OLED) driven by low-voltage operation organic TFT. In order to achieve high-quality and high-resolution moving images, OTFTs with high performances such as a high mobility, high ON/OFF ratio, low sub-threshold slope (SS) and low operating voltage, are developed. We fabricated pentacene-based low-voltage operation OTFT with a Ta2O5 gate dielectric prepared at a low temperature process. The resulting OTFT array showed a high mobility of 0.3-0.4 cm2/Vs, ON/OFF ratio over 107, VTH=2.7V, and low SS=0.3 V/decade. OTFTs with solution-processable materials such as fluoropolymer gate dielectric and liquid-crystalline semiconducting polymers, PBTTT, were also investigated. Electrical characteristics and stabilities of these devices will be discussed. In the final section, we will demonstrate OTFT-driven flexible displays. Both of the flexible LC device and the OLED device were successfully integrated on the pentacene-based OTFT arrays. Printing and lamination techniques were introduced to assemble the flexible LC device. Phosphorescent polymer materials, which can be patterned by ink-jet printing, were used for emitting layer of OLED. Color moving images were successively shown on the resulting 5-inch displays using an active-matrix driving technique of the OTFT at a low driving voltage of 15V.
In this study, we have investigated the effect of surface treatment on the orientation and mobility of pentacene by using a photoreactive polyimide film to modify the gate-insulator surfaces of organic field effect transistors (OFETs). Surface modification includes a photoreactive polyimide film, presenting a passivated interface on which the semiconductor can grow. This polyimide film can control of the orientation of semiconductor by using linearly polarized deep UV (LPDUV) irradiation. Fabricated OFETs include stacked structures of Ta2O5 as the gate insulators and the photoreactive polyimide. Most of the characteristic parameters of the OFETs, such as carrier mobility and on/off current ration, have been improved by using the photo-alignment treatment achieved with LPDUV irradiation.
The impact of the unusually severe drought associated with the 1997–1998 El Niño on tropical forest dynamics in Sarawak, Malaysia was examined. Mortality during the non-drought period (1993–1997) in a core plot (1.38 ha) was 0.89 % y−1, while that during the drought period (1997–1998) in the same plot and a peripheral plot was 6.37 and 4.35 % y−1, respectively. The basal area lost in the drought interval was 3.4 times that of the annual incremental basal area in 1993–1997. Drought mortality was higher for the smaller trees, though it was less size dependent than the non-drought mortality. Dipterocarpaceae, which is the dominant family in the study plot, had a mortality 12–30 times higher in the drought than the non-drought period. There were no significant differences in mortality among the topographic types. From the results of a log-linear model (multi-factored contingency table), the death of trees was correlated with size class, indicating a change in the size-class structure of the forest. Thus, both the species composition and structure are totally affected by such an episodic drought even in a per-humid tropical forest.
In order to clarify the effect of mineral alteration on nuclide migration, we examined the processes, mechanisms, and kinetics of chlorite weathering, and the uranium concentrations in minerals and rocks at Koongarra, Australia. The observed concentrations of uranium in rocks were compared to those calculated. The sequence of chlorite weathering may be simply expressed as a chlorite → vermiculite → kaolinite conversion. These minerals occur as a function of depth, which corresponds well to uranium concentrations on the meter scale. Iron minerals, closely related to the uranium redistribution, are released during the weathering. The first-order kinetic model of the weathering process suggests that the weathering rate is not constant but time-dependent. The uranium concentrations are qualitatively proportional to the extent of the weathering; the weathered part having higher uranium concentration. Uranium mainly occurs with iron minerals, and sub micron sized saléeite, a uranyl phosphate, is one of the most probable uranyl phases associated with the iron minerals. The uranium fixation mechanisms are probably saléeite microcrystal coprecipitation and sorption to the iron minerals. Our model, which describes uranium concentrations in rocks as a function of time, shows that the transition zone (a vermiculite dominant area) plays an important role in the uranium migration. We have established that weathering of chlorite has affected the redistribution of uranium for more than one million years. The present study demonstrates the significance of mineral alteration when we estimate nuclide migration for geologic time.
The anisotropic powder metallurgy of n-type Bi2Te2.85Se0.15 doped with bromines was studied by both x-ray diffraction and thermoelectric measurements. The statistical orientation of platelet-like grains in the samples was characterized using the orientation factor estimated by the Lotgering formula from (0,0,1) x-ray diffraction intensities. It is demonstrated that the orientation factor which is strongly influenced by the hot-pressing conditions and the particle size of the starting material has a strong effect on the thermoelectric properties of the samples in this system. This implies that the powder metallurgy has the additional freedom of controlling the thermoelectric properties in addition to the doping level in the grains.
As is known well, the inflationary universe model resolves most of the fundamental problems concerning the large scale structure of the universe and is now becoming a standard model for the early universe. However, there is one important problem yet to be made clear. In this model the number density of particles effectively goes to zero during the inflation and everything is created after the universe is heated up again at the end of inflation. Since the reheating temperature is much lower than the GUT temperature in general, however, it is not clear whether the observed baryon asymmetry is generated in this process.
Recently cosmology with unstable particles has attracted much attention as a possible solution to several important problems in the present universe. In this scenario, however, nonlinear structures in the universe would not easily form since their binding energy would decrease gradually in the course of the decay of unstable particles. Thus this scenario is stringently constrained by the galaxy formation problem. In order to obtain the constraints quantitatively, we carried out numerical calculations of the evolution of density perturbations after the time of recombination. Universe is assumed to consist of three components; unstable X-particles, its non-radiative decay product (massless particles) and baryons. Initial conditions are specified by the density contrast of X-particles δX,i and the baryon density parameter Ωb,i. Resultant baryon density contrast at Z = 4 (epoch of galaxy formation) and Z = 0 (present) is shown below for Ωb,i = 0.005.
Following the standard scenario of galaxy formation, density fluctuations with amplitude δ∼10−3 should have been present at the recombination time tR in order that galaxies and clusters of galaxies can be formed. Recent observations of the anisotropy of the cosmic background radiation(CBR), however, indicate that δ is less than 10−4 at tR for adiabatic perturbations in the baryon-dominated universe.
Epsilon Aurigae has been observed during ingress and totality between 1982 and 1983 at Okayama. Analyses of profiles of Ha line and of radial velocities of neutral hydrogen and metals show that the secondary component consists of at least three parts in structure.