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To characterise the dissemination patterns of uropathogenic Escherichia coli (UPEC) in a community, we conducted a study utilising molecular and fundamental descriptive epidemiology. The subjects, consisted of women having community-acquired acute urinary tract infection (UTI), were enrolled in the study from 2011 to 2012. UPEC isolates were subjected to antibacterial-susceptibility testing, O serogrouping, phylotyping, multilocus-sequence typing with phylogenetic-tree analysis and pulsed-field-gel electrophoresis (PFGE). From the 209 unique positive urinary samples 166 UPEC were isolated, of which 129 were fully susceptible to the tested antibiotics. Of the 53 sequence types (STs), the four most prevalent STs (ST95, ST131, ST73 and ST357) accounted for 60% of all UPEC strains. Antimicrobial resistance was less frequently observed for ST95 and ST73 than for the others. A majority of rare STs and a few common STs constituted the diversity pattern within the population structure, which was composed of the two phylogenetically distinct clades. Eleven genetically closely related groups were determined by PFGE, which accounted for 42 of the 166 UPEC isolates, without overt geo-temporal clustering. Our results indicate that a few major lineages of UPEC, selected by unidentified factors, are disseminated in this community and contribute to a large fraction of acute UTIs.
A scantling X-ray fluorescence(XRF) microprobe using WoIter type 1 optics was developed, and micro and trace element analysis was carried out using synchrotron radiation up to 10 keV as an excitation source. The design parameters of the optical system and the performance of the system, such as the beam size and the intensity, are described. The MDL obtained for Mn was 6 ppm in relative concentration and about 0.1 pg in absolute amount. The estimated spatial resolution was better than 10 um.
We present here the fundamental idea of the conversion method between old and new reference frameworks. Some practical applications are made for the optical observations for Tokyo PZT. The method can be also applied to the conversion of radio sources where we have met a great difficulty in performing the conversion because of no citation of observation epochs in general. We discuss their necessity in order to establish a concrete compilation of the position of the radio sources.
Urocanic acid (UCA) is known as a major chemoattractant for Strongyloides stercoralis infective third-stage larvae (L3). Since Brugia pahangi is a skin-penetrating parasitic nematode similar to S. stercoralis, UCA was expected to be a chemoattractant for B. pahangi L3. Thus, the chemoattractant activity of UCA for B. pahangi L3 was assessed. The chemotactic responses of B. pahangi L3 to UCA or acetic acid (CH3COOH) dissolved in amine solutions were assessed using an agar-plate assay. A test solution of 200 mm UCA dissolved in aqueous 270 mm tris(hydroxymethyl)aminomethane (Tris) significantly attracted B. pahangi L3 compared with deionized water (DW), while neither a solution of 200 mm UCA dissolved in aqueous 230 mm ammonia (NH3) nor 290 mm triethylamine (TEA) significantly attracted L3. Similarly, a test solution of 200 mm CH3COOH dissolved with 200 mm Tris significantly attracted L3, but neither a test solution of 200 mm CH3COOH plus 200 mm NH3 nor 200 mm TEA attracted L3. Furthermore, L3 were significantly attracted to 200 mm Tris alone, compared with DW, but avoided 200 mm NH3 and 200 mm TEA. Moreover, the chemoattractant activity of Tris for L3 was observed even at a low concentration of 25 mm, and it was observed in a mild alkaline condition but not in an acidic condition. The present study reveals that Tris is a potential chemoattractant for B. pahangi L3 while UCA is not. This finding will contribute to an understanding of the mechanisms of skin-penetrating infection of filarial L3.
We report the results of abundance analysis for high-resolution spectra of eight extremely metal-poor turn-off stars selected from SDSS/SEGUE. Based on differential analysis adopting stellar parameters from Balmer line profiles, we obtain the following results: i) Statistically significant scatter is found in [X/Fe] (X=Na, Mg, Cr, Ti, Sr and Ba), among which [Na/Fe] shows an apparent bimodal distribution, ii) Li abundances are ~0.3 dex lower in [Fe/H]<−3.5 than the Spite plateau value without significant scatter.
We report here the results of deep optical spectroscopy of the very extended emission-line region (VEELR) found serendipitously around the Seyfert 2 galaxy NGC 4388 in the Virgo cluster. The Hα recession velocities of most of the filaments of the region observed are highly blue-shifted with respect to the systemic velocity of the galaxy. The velocity field is complicated, and there seem to be several streams of filaments ranging from ~ −100 km s−1 to ~ −700 km s−1 with respect to the systemic velocity of the galaxy. The emission-line ratios of the VEELR filaments are well explained by power-law photoionization models with solar abundances. In addition to photoionization, shock heating probably contributes to the ionization of the gas. We conclude that the VEELR was formerly the disk gas of NGC 4388, which has been stripped by ram pressure due to the interaction between the hot intra-cluster medium (ICM) and the galaxy.
We developed a slit-scanning type 3D-spectroscopic system named as Spectronebulagraph (hereafter SNG; Kosugi et al. 1994) at Okayama Astrophysical Observatory. A detailed description about SNG is presented by Ohtani et al. elsewhere in this colloquium. We present here the results of the 3D-spectroscopy of four nearby active galaxies by using SNG.
This nearby (at distance of 5.4 Mpc) Magellanic irregular galaxy has many H II regions in its main body suggesting violent star-formation activity. We performed tridimensional observations of NGC 4449 using SNG in order to obtain detailed kinematic structure and then to investigate the star-formation mechanism of NGC 4449. Hα intensity map, Hα velocity field are shown in figure 1. As is obvious in lower panel of figure 1, no global rotational motion was detected. Most impressive feature of the velocity field is kpc-scale mosaic structure of low velocity and high velocity components. Also, many filamentary components were newly found in 3D-datacube of the SNG observation.
We previously reported an association between human parechovirus type 3 (HPeV3) and epidemic myalgia with myositis in adults during summers in which an HPeV3 outbreak occurred in children. However, this disease association has not yet been reported elsewhere. We have since continued our surveillance to accumulate data on this disease association and to confirm whether myalgia occurs in children as well as adults. Between June and August 2014, we collected 380 specimens from children with infectious diseases. We also collected clinical specimens from two adult and three paediatric patients suspected of myalgia. We then performed virus isolation and reverse-transcription–PCR using the collected specimens. We detected HPeV3 in 26 children with infectious diseases, which we regarded as indicating an outbreak. We also confirmed HPeV3 infection in all patients suspected of myalgia. In particular the symptoms in two boys, complaining of myalgia and fever, closely matched the criteria for adult myalgia. Based on our findings from 2008, 2011 and 2014, we again urge that clinical consideration be given to the relationship between myalgia and HPeV3 infections during HPeV3 outbreaks in children. Furthermore, our observations from 2014 suggest that epidemic myalgia and myositis occur not only in adults but also in children.
We prepared silicon hyperdoped with sulfur by ion-implantation followed by pulsed laser melting. Effects of laser fluence during pulsed laser melting and of post-annealing on the silicon hyperdoped with sulfur are investigated. The structure of hyperdoped layer changes from poly-to mono-crystal with increasing laser fluence. Interface between sulfur-implanted-layer and single-crystal substrate disappear above 1.1 J/cm2. The spectral intensity of mid-infrared (MIR) optical absorption increases with crystallinity and spectral shape depends on whether the melt depth during pulsed laser melting reaches interface between implanted layer and single-crystal silicon substrate or not. The MIR absorption intensity rapidly decreases with thermal annealing temperature and almost disappears at 750 °C. The activation energy of conductivity decreases with increasing laser fluence and further decreases with increasing post thermal-annealing temperature. The insulator-metal transition is observed for the sample annealed at 750 °C. These results indicate that there is no direct correlation between MIR optical absorption band and insulator-metal transition.
The transmission of human metapneumovirus (hMPV) among family members is not well understood. We identified 15 families in which multiple members were diagnosed with hMPV infection by real-time PCR in 2008 and 2010. Index patients ranged in age from 2 years to 11 years (median 5 years), and all 15 index cases were children who attended primary school, kindergarten, or nursery school. Contact patients ranged in age from 2 months to 46 years (median 6 years). Excluding five adult cases, contact patients were significantly younger than index patients (P = 0·0389). Of the 12 contact children, seven (58%) were infants who were taken care of at home. The serial interval between the onset of symptoms in an index patient and the onset of symptoms in a contact patient was estimated to be 5 days. These results suggest that the control of school-based outbreaks is important for preventing hMPV infection in infants.
In vitro chemotactic responses of infective third-stage larvae (L3) of Brugia pahangi to NaCl, Na2HPO4, KCl, K2HPO4, MgCl2 and CaCl2 were assessed. Compared to deionized water as a control, 200 mm NaCl and 100 mm Na2HPO4 significantly attracted L3 (P < 0.01 and P < 0.01), whereas L3 were likely to avoid 200 mm KCl and 100 mm K2HPO4 (P < 0.05 and P < 0.05). L3 showed no significant tendency to avoid or to be attracted to 200 mm CaCl2 and 200 mm MgCl2. Furthermore, NaCl exhibited a significant chemoattractant activity for L3 at a low concentration of 100 mm.
The significance of the potential impacts of microbial activity on the transport properties of host rocks for geological repositories is an area of active research. Most recent work has focused on granitic environments. This paper describes pilot studies investigating changes in transport properties that are produced by microbial activity in sedimentary rock environments in northern Japan. For the first time, these short experiments (39 days maximum) have shown that the denitrifying bacteria, Pseudomonas denitrificans, can survive and thrive when injected into flow-through column experiments containing fractured diatomaceous mudstone and synthetic groundwater under pressurized conditions. Although there were few significant changes in the fluid chemistry, changes in the permeability of the biotic column, which can be explained by the observed biofilm formation, were quantitatively monitored. These same methodologies could also be adapted to obtain information from cores originating from a variety of geological environments including oil reservoirs, aquifers and toxic waste disposal sites to provide an understanding of the impact of microbial activity on the transport of a range of solutes, such as groundwater contaminants and gases (e.g. injected carbon dioxide).
Pseudoelastic behavior of Fe3Ga single crystals regardless of a thermoelastic martensitic transformation was investigated focusing on the dislocation structure and the phase constituent. Large pseudoelasticity of 5 % recoverable strain appeared in Fe3Ga single crystals sufficiently annealed in the D03 single-phase region. In the crystals, uncoupled and paired 1/4 superpartial dislocations moved dragging the nearest-neighbor (NN) and next-nearest neighbor (NNN) anti-phase boundaries (APBs) during loading, respectively. During unloading, these APBs pulled back the superpartials resulting in large pseudoelasticity, which is similar to D03-ordered Fe3Al crystals. The dislocation configuration was closely related to the ordered domain structure developed in the D03 phase. Moreover, the precipitation of the thermally stable L12 phase was so slow that the metastable D03 phase developed even if the crystals were annealed in the (a+ L12) and (D03+ L12) phase fields in Fe-Ga equilibrium phase diagram. The metastable D03 phase also demonstrated large pseudoelasticity of which recovery ratio was above 80 %. On the other hand, if the L12 phase precipitated by long time annealing in the (a+ L12) region, the reversible motion of 1/4 superpartials was suppressed by the L12 phase resulting in a decrease in recovery ratio. In addition, the crystals aged in the (a+ D03) phase region showed small strain recovery.
The temperature and field dependence of the de Haas-van Alphen oscillations in θ- (BEDT-TTF)2l3 is analyzed. The cyclotron masses are estimated to be 2.0 Me and 3.6 me for slow and fast oscillations, respectively. The indication of magnetic breakdown effect is discussed in terms of the geometry of the Fermi surface. The results are compared with those of the infrared reflectance spectra.
The Shubnikov-de Haas (SdH) and Magnetoresistance Measurements have been performed in an organic Metal β″ (BEDT-TTF)2AuBr2. Absence of saturation in the magnetoresistance up to 13T suggests that this salt is a compensated Metal. The SdH oscillations are consistently understood by assuming that three cylindrical Fermi surfaces are present. The frequencies of the SdH oscillations corresponding to the Fermi surfaces are determined to be 41.5 T, 139 T, and 181 T for H//b*-axis. An anomalous maximum in the resistance is found at about 9.5 K for H//b*-axis although no anomaly is observed for H//plane.
Nanocrystalline TiAl powder was formed by the modified HDDR (hydrogenation-disproportion-dehydrogenaton-recombination) method utilizing ball milling in a hydrogen atmosphere. That is, TiAl compound powder decomposed into TiH2 and Al-rich TiAl powders by mechanical grinding in a hydrogen atmosphere (HD process). Dehydrogenaton-recombination (realloying) resulted in the formation of nanocrystalline TiAl powder when heated to about 700 K in an argon atmosphere (DR process). Almost fully dense nanocrystalline TiAl compacts were prepared by a combination of HDDR and hot-pressing at 873 K which is lower than the usual consolidation temperature by about 300 K. The TiAl compact thus made was brittle in the as-pressed state but showed compressive ductility after annealing.
Bulk GaN crystals up to several mm in size, grown by a Na/Ga flux method, have been characterized using room and low temperature photoluminescence (PL) and panchromatic cathodoluminescence (CL) imaging. Highly resolved excitonic PL spectra are obtained for material grown in a new, large-scale reactor. The crystal polarity affects the incorporation of residual Zn and Mg or Si acceptors and the deep level luminescence bands in c-oriented platelets. A Zn (A°,X) triplet structure with unusual thermalization properties and a highly resolved structural defect related PL peak are observed. Striations are found in some of the smaller platelets by CL imaging, but are absent in the prismatic crystals.
Sputtered Pb(Zr, Ti)O3 thin films with superior ferroelectric properties were successfully obtained by controlling the grain structure and the film compositions. We found that amorphous PbTiO3 buffer layers are effective in forming PZT thin films with fine dense grains. The sputtered PZT thin films with Ti-rich phase showed excellent ferroelectric properties. The polarization retention properties of PZT capacitors with Ti-rich phase are remarkable, and the value of the retained polarization density after 10 years is expected to be larger than 40 μC/cm2. Further, 150-nm-thick PZT capacitors with Zr/Ti=30/70 showed 2P, at 1.5 V of more than 30 μC/cm2, and good retention property. These results indicate the potential of the lower voltage operation of sputtered PZT capacitors by optimizing the film composition and thickness.
A novel spin on material derived from perhydropolysilazane that converts into ultra-low k inorganic films is described in this paper. The obtained films, cured at 400°C in N2 atmosphere, exhibit dielectric constants as low as 1.6 which do not change after holding the wafers in a clean-room mbient for 2 months. Cross-sectional SEM images of the cured films show the aggregation of small granules with diameters ranging from 5 to 30 nm. The films can be obtained by conventional SOG process: spin-coating, baking and curing, without any additional process such as hydrophobic treatment.
The average atomic compositions of the films are, Si/O/N/C = 40/55/5/0.5 (atomic %), by XPS analysis. These results indicate that the films have hydrogen silicon oxynitride structures. No evolution of H2O and NH3 was detected by TDS analysis in the temperature range of RT to 800°C. Hydrophobic Si-H and Si-H2 groups remaining in the film might prevent water absorption, resulting in the low dielectric constant.
The remainder of Si-H and Si-H2 constituents in the cured films is the result of selective oxidation reactions of perhydropolysilazane in the baking process with the use of a specific catalyst. The structures of the films are tailored by altering the amount of the catalyst. In this study, we also demonstrate the relationship between the effect of the catalyst and the film properties.