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Dog treats might be contaminated with Salmonella. In Canada and the USA, outbreaks of human salmonellosis related to exposure to animal-derived dog treats were reported. Consequently, surveillance data on Salmonella contamination of dog treats have been gathered in many countries, but not in Japan. In the current study, we investigated whether dog treats in Japan were contaminated with Salmonella. Overall, 303 dog treats (of which 255 were domestically produced) were randomly collected and the presence of Salmonella investigated. Seven samples were positive for Salmonella enterica subsp. enterica. Among these isolates, three were identified as serovar 4,5,12:i:–; two were serovar Rissen; and two were serovar Thompson. All serovar 4,5,12:i:– and Thompson isolates were resistant to one or more drugs. Two serovar Rissen isolates were fully susceptible to all tested antimicrobial agents. All Salmonella isolates were susceptible to cefotaxime, ciprofloxacin and nalidixic acid. The gene blaTEM was detected in two serovar 4,5,12:i:– isolates. The blaCTX−M and blaCMY genes were not detected in any isolates. This study demonstrated that dog treats in Japan could constitute a potential source of dog and human Salmonella infections, including multidrug-resistant Salmonella isolates.
The present study investigated the dry matter yield (DMY) and arbuscular mycorrhizal (AM) colonization (internal hyphae, arbuscules, and vesicles) of two genotypes of zoysia grass (Zoysia japonica strain Aso and cv. Asagake) at three rates (10, 20 and 40 g N/m2/year) of application of digested slurry (DS) or mineral fertilizer. Soil chemical properties (available phosphorus concentration, pH and electrical conductivity (EC)) were also measured as factors associated with AM colonization. The fertilizer type (DS v. mineral fertilizer) had an effect on DMY depending on the plant genotypes but had little or no effect on AM colonization, and soil chemical properties, indicating that DS can be used as a substitute for mineral fertilizer; however, it is necessary to apply it taking into account the ratio of inorganic nitrogen (N). However, heavy DS application decreased colonization by internal hyphae. Furthermore, even at the lowest rate, the continuous application of DS decreased colonization by arbuscules and vesicles in both genotypes, which were associated with decreasing soil pH and increasing EC. The results suggest that zoysia grass should be fertilized with DS at a rate of <10 g N/m2/year in order to achieve a continuous association with AM fungi, although this range of N application is sub-optimal for zoysia grass production.
Observations of the structure and the velocity field in the L1551 bipolar flow were made with the 45m telescope at Nobeyama in the 115GHz 12CO J = 1 – 0 line with high spatial resolution. It was found that the bipolar flow lobes have a clear hollow cylindrical structure and show evidence of a helical velocity field. They appear to rotate in the same direction as the CS disk found by Kaifu et al. (1984). The velocity of the flow in the bipolar directions increases with distance up to ∼ 3′ from the central object, IRS 5. These characteristics coincide with those predicted by the magnetodynamic theory proposed by Uchida and Shibata and indicate the essential importance of the magnetic field in producing such flows and also in the star-formation process itself through the enhancement of angular-momentum loss.
We have made 15″ resolution observations of CO J = 1-0 emission toward L723 and S140 using the Nobeyama 45-m radio telescope. The maps resolved the molecular flow structures clearly. The outflow in the S140 molecular cloud was resolved to be a bipolar structure with its axis being nearly perpendicular to the elongation of the dense core observed in CS emission and to the direction of the infrared polarization. The blueshifted and redshifted components in L723 were resolved into two pairs of bipolar outflows with a point-symmetric structure.
Microscopic observation of air-hydrate crystals was carried out using 34 deep ice-core samples retrieved at Vostok Station, Antarctica. Samples were obtained from depths between 1050 and 2542 m, which correspond to Wisconsin/Sangamon/Illinoian ice. It was found that the volume and number of air-hydrate varied with the climatic changes. The volume concentration of air-hydrate in the interglacial ice was about 30% larger than that in the glacial ice. In the interglacial ice, the number concentration of air-hydrate was about a half and the mean volume of air-hydrate was nearly three times larger than that in the glacial-age ice. The air-hydrate crystals were found to grow in the ice sheet, about 6.7 × 10−12 cm3 year-1, in compensation for the disappearance of smaller ones. The volume concentration of air-hydrate was related to the total gas content by a geometrical equation with a proportional parameter α. The mean value of α below 1250 m, where no air bubbles were found, was about 0.79. This coincided with an experimentally determined value of the crystalline site occupancy of the air-hydrate in a 1500 m core obtained at Dye 3, Greenland (Hondoh and others, 1990). In the depth profile of calculated α for many samples, α in the interglacial ice was about 30% smaller than that in the glacial-age ice.
Empirical studies suggest that cost-share programs are unlikely to reduce exploitation of ground water and nonpoint-source pollution. By introducing an induced irrigation technology in our model, we find theoretically that the optimal amount of irrigation water and nitrogen fertilizer increases (decreases) when the increased rate of the marginal net economic benefits from their use with an induced irrigation technology exceeds (is less than) an increase in the rate of irrigation efficiency. Our results suggest that producers should use relatively more irrigation water and fertilizer when greater quantities of high-value crops are grown because producers will adopt improved irrigation technologies for such crops.
Prototypes of magnetic actions in producing and shedding the X-ray-emitting high temperature plasmas in various astrophysical objects are witnessed in the spatially-resolved form on the Sun by the Solar X-ray Satellite “Yohkoh”. The most prominent of those are arcade flarings seen as powerful arcade flares in active regions with strong magnetic field. Larger scale fainter X-ray arcade formation observed at high latitudes, shedding a large amount of mass and energy as CME's (coronal mass ejections) also belongs to this category. Since some features found by the new observation by Yohkoh are incompatible with the so-called “classical model of arcade flarings”, we advance an alternative model based on the quadruple magnetic sources in the photosphere.
In the present paper, we stress the importance of the magnetic field in the problem of acceleration and collimation of astrophysical jets, and discuss our proposed generic picture for such “central gravitator + jets + lobes” systems and inherent interpretations of the various observational characteristics of such systems: Mechanisms are proposed for (1) the enhanced liberation of gravitational energy at the central object, (2) the transfer of a part of the liberated energy along the large-scale magnetic field by large-amplitude, torsional Alfvén wave trains that form collimated jets (we call this a sweeping pinch process), (3) the dumping of the transferred energy at the end of the jets when they impinge on the denser region outside the border of the “cavity” from which the mass contracted to the central condensation (central gravitator + accretion disk, as well as the larger-scale condensation surrounding them), and (4) the formation of wiggled jets and lobes as helical kinks and the tucked-up magnetic field produced in the sweeping pinch process, respectively.
In the previous work, it is reported that the Spin-Seebeck effect (SSE), which refer to the generation of a spin current from a temperature gradient, can be enhanced by Fe interface treatment. Here, we investigated the Fe thickness (dFe) dependency of spin-Seebeck voltage (VSSE) and mixing conductance (gr) in Pt/Fe/Bi:YIG/SGGG system. As a result, magnitude of VSSE had a peak at dFe ≓ 1 ML (monolayer , ≓ 0.3 mm), and also increase of gr was saturated at this point. It suggests that VSSE increase with increasing gr when dFe is smaller than 1.0 ML. For the case in which dFe is larger than 1.0ML, however, VSSE decreases due to a spin current decay in Fe layer with a constant gr. These experimental results are consistent with previous theoretical works.
Time series of SXT (Soft X-ray Telescope) images have revealed many jet-like features in the solar corona. Typical size of the “jet” is 5 × 103 – 4 × 105 km, the typical projected velocity is 30 – 300 km/s, and the kinetic energy estimated to be 1025 – 1028 erg. Many of the jets are associated with flare-like bright points or sub-flares. Three typical examples are discussed, including an X-ray jet identified with an Hα surge. It is suggested that magnetic reconnection is one of the possible mechanisms to produce these X-ray jets.
A magnetohydrodynamic simulation in a 2.5D approximation is performed for the quadrupole source model for arcade flares treated years ago by Uchida (1980), and recently supported by the observations from Yohkoh. It is shown that this model can explain several key characteristic features of arcade flares found by Yohkoh, and can avoid some of the paradoxes existing in the “classical model”.
Radiocarbon analysis of the carbonaceous aerosol allows an apportionment of fossil and non-fossil sources of airborne particulate matter (PM). A chemical separation of total carbon (TC) into its subtractions organic carbon (OC) and elemental carbon (EC) refines this powerful technique, as OC and EC originate from different sources and undergo different processes in the atmosphere. Although 14C analysis of TC, EC, and OC has recently gained increasing attention, interlaboratory quality assurance measures have largely been missing, especially for the isolation of EC and OC. In this work, we present results from an intercomparison of 9 laboratories for 14C analysis of carbonaceous aerosol samples on quartz fiber filters. Two ambient PM samples and 1 reference material (RM 8785) were provided with representative filter blanks. All laboratories performed 14C determinations of TC and a subset of isolated EC and OC for isotopic measurement. In general, 14C measurements of TC and OC agreed acceptably well between the laboratories, i.e. for TC within 0.015–0.025 F14C for the ambient filters and within 0.041 F14C for RM 8785. Due to inhomogeneous filter loading, RM 8785 demonstrated only limited applicability as a reference material for 14C analysis of carbonaceous aerosols. 14C analysis of EC revealed a large deviation between the laboratories of 28–79% as a consequence of different separation techniques. This result indicates a need for further discussion on optimal methods of EC isolation for 14C analysis and a second stage of this intercomparison.
The prevalence of Helicobacter pylori infection in Indonesia is controversial. We examined the H. pylori infection rate in 78 patients in a hospital in Surabaya using five different tests, including culture, histology, immunohistochemistry, rapid urease test, and urine antibody test. Furthermore, we analysed virulence factors in H. pylori strains from Indonesia. The H. pylori infection rate was only 11·5% in all patients studied, and 2·3% of Javanese patients and 18·0% of Chinese patients were infected (P = 0·01). Although severe gastritis was not observed, activity and inflammation were significantly higher in patients positive for H. pylori than in patients negative for H. pylori. Among genotypes identified from five isolated strains, cagA was found in four; two were vacA s1m1. All cagA-positive strains were oipA ‘on’ and iceA1 positive. We confirmed both a low H. pylori infection rate and a low prevalence of precancerous lesions in dyspeptic patients in a Surabaya hospital, which may contribute to the low incidence of gastric cancer in Indonesia.
We present the discovery of out-flow like plasma emissions with the Suzaku and ASCA data. Those plasmas have a size of ∼150 pc. Remarkably, the southern plasma is in a recombination dominant phase, which is not predicted by standard shock heating. A plausible scenario is either photoionization due to strong jet-like X-rays from Sgr A* or rapid cooling due to adiabatic expansion of a blowout plasma from the Galactic center about 105 years ago.
A discharge-emission spectrometer and a cavity ringdown spectrometer have been developed to aid in the solution to the diffuse interstellar band (DIB) problem. A hollow cathode was used to generate molecular ions in a discharge because it has been suggested that molecular ions are probable DIB candidates. The discharge was produced by a pulsed voltage of 1300–1500 V. A wide wavelength range of optical emission from the discharge was examined by a HORIBA Jobin Yvon iHR320 monochromator. The dispersed discharge emission was detected by a photomultiplier and was recorded via a lock-in amplifier. The 2B3u–X2B2g electronic transition of the butatriene cation H2CCCCH2+ was observed in the discharge emission of 2-butyne H3CCCCH3. The frequency of the electronic transition was measured to be 20381 cm−1, and a comparison study was made with known DIB spectra.
The resolution of the discharge-emission spectrometer is insufficient to make precise comparisons between laboratory frequencies and astronomically observed DIB spectra. We therefore developed the cavity ringdown spectrometer using the same hollow cathode. The high sensitivity of this spectrometer was confirmed by the observation of the forbidden band of O2.
We observed significant reduction of thermal conductivity in semiconducting composite films of Si and molybdenum (Mo)-silicide nanocrystals (NCs). These films were synthesized by phase separation due to annealing at 700 -1000°C from sputtered amorphous Mo–Si alloy. Transmission electron microscope images showed that the NCs were grown to diameters of∼10 nm in the films by annealing at 800°C. Raman scattering spectra showed lower shift of peak positions of Si transverse optical (TO) phonon due to the confinement effect and the tensile stress. The electrical resistivity of the films was 0.17- 9 Ωm at room temperature and showed a semiconducting temperature dependence at 20-400 K. Thermal conductivity of the film was reduced to 4.4 W/mK by enhancement of phonon scattering at NC interfaces, suggesting that the composite film is promising as a high-efficiency Si-based thermoelectric material.
For appropriate safety assessment of TRU waste disposal, the dominant chemical species of 14C-gas was studied. [1,2-14C] sodium acetate was added to flooded paddy soil samples, and the content of 14C in the soil, solution, and the emitted CO2 gas during incubation period was determined. Recovery ratios of the total 14C activity to the initial 14C activity were 97.9% at day 1, 86.4% at day 3, and 83.5% at day 7 of incubation. The result of the day 1 means that the emitted 14C-gas was almost 14CO2. At day 7 of incubation, about 16.5% of 14C was failed to recover. Even if the unknown 14C was gases other than 14CO2, the dominant chemical species of the emitted 14C-gas will be 14CO2, because the recovery ratio of the 14CO2 was 48.9% (¿16.5%). Sodium 2-bromoethane-sulfonate was used to ensure the emission of CH4, but there was no effect of the regent to the recovery ratio of 14CO2. Methane emission may be little under our experimental conditions. These results suggest that the dominant chemical species of the emitted 14C-gas from the flooded paddy soil samples was 14CO2.
We synthesized amorphous semiconductor films composed of Mo-encapsulating Si clusters (MoSin : n∼10) on solid substrates. The MoSi10 films had Si networks similar to hydrogenated amorphous Si and an optical gap of 1.5 eV. Electron spin resonance signals were not observed in the films indicating that dangling bonds of Si were terminated by Mo atoms. We fabricated thin-film-transistors using the MoSi10 film as a channel material. The electric field effect of the film was clearly observed. This suggests that the density of mid-gap states in the film is low enough for the field effect to occur.
We present a first-principles lattice dynamics for the assembly of the transition-metal (M)-encapsulated Sin clusters in amorphous phase (a-MSin), which has been proposed as a potential candidate for the channel material of the next-generation thin-film transistors (TFTs) [N. Uchida et al., Appl. Phys. Express1, 121502 (2008)]. The shape of calculated vibrational density of states (VDOS) curve of a-MoSi10 is similar to the counterpart of the high pressure phase of a-Si (HPA-Si) although the present systems are obtained as a result of pressure relaxation. Its radial distribution function (RDF) among Si themselves is characterized by the absence of a gap between the first and second shells, which is also the case in . We further present the VDOS of a-WSi10, whose curve shape is again similar to that of HPA-Si. A difference between a-MoSi10 and a-WSi10 is that the W-atom displacement components extracted from the vibration eigenvectors are mainly distributed over a lower frequency range (< ~ 150 cm-1) than the Mo counterpart (~ 150 cm-1 to ~ 300 cm-1). This may be attributed to a larger atomic mass of W than Mo.