To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
An outbreak of serotype 19A Streptococcus pneumoniae occurred among the residents of a relief facility. Pneumonia developed in 5 of 99 residents (attack rate, 5.1%). We obtained pharyngeal specimens from non-onset residents, and S. pneumoniae was isolated from 6 individuals (6.4%), 5 of whom had serotype 19A.
No previous studies have examined Mycobacterium avium complex pulmonary disease (MAC-PD) in only elderly patients ⩾75 years old. Here, we investigated the exacerbating factors of MAC-PD in elderly patients and clarified cases that can be followed up without MAC medication. From April 2011 to March 2019, 126 advanced aged patients at our institute were newly diagnosed with MAC-PD, and could be observed based on radiological findings for over a year. Their medical records were retrospectively examined for clinical and radiological findings at the time of diagnosis and 1 year later. To identify the predictors of exacerbation, clinical characteristics of 109 treatment-naïve patients were compared between exacerbated and unchanged groups. Additionally, the unchanged group was followed for one more year. In the current study, positive acid-fast bacilli smears from the sputum test, the presence of cavitary lesions and extensive radiological findings, particularly abnormal shadows in ⩾3 lobes, were predictive of exacerbation among treatment-naïve elderly MAC-PD patients. In the unchanged group, <10% showed exacerbation of radiological findings within the subsequent year. In conclusion, if the sputum smear is negative, no cavitary lesions are present, and abnormal shadows are restricted to ⩽2 lobes, elderly patients with MAC-PD may remain untreated for a few years.
SCFA increase serotonin (5-hydroxytryptamine, 5-HT) synthesis and content in the colon in vitro and ex vivo, but little is known in vivo. We tested whether dietary indigestible saccharides, utilised as a substrate to produce SCFA by gut microbiota, would increase colonic 5-HT content in mice. Male C57BL/6J mice were fed a purified diet and water supplemented with 4 % (w/v) 1-kestose (KES) for 2 weeks. Colonic 5-HT content and enterochromaffin (EC) cell numbers were lower in mice supplemented with KES than those without supplementation, while monoamine oxidase A activity and mRNA levels of tryptophan hydroxylase 1 (Tph1), chromogranin A (Chga), Slc6a4 and monoamine oxidase A (Maoa) genes in the colonic mucosa, serum 5-HT concentration and total 5-HT content in the colonic contents did not differ between groups. Caecal acetate concentration and Bifidobacterium pseudolongum population were higher in KES-supplemented mice. Similar trends were observed in mice supplemented with other indigestible saccharides, that is, fructo-oligosaccharides, inulin and raffinose. Intragastric administration of live B. pseudolongum (108 colony-forming units/d) for 2 weeks reduced colonic 5-HT content and EC cell numbers. These results suggest that changes in synthesis, reuptake, catabolism and overflow of 5-HT in the colonic mucosa are not involved in the reduction of colonic 5-HT content by dietary indigestible saccharides in mice. We propose that gut microbes including B. pseudolongum could contribute to the reduction of 5-HT content in the colonic mucosa via diminishing EC cells.
Ferroelectric electro-optics materials are widely studied for optical applications, such as optical switches, optical scanners, and optical shutters. However, conventional operation of those devices requires a continuous external electrical field. On the other hand, our group proposes an optical property memory effect by controlling domain structure as either full-polarized or depolarized state using asymmetric voltage operation. The optical property memory effect can keep its optical value, such as refractive index and light transmittance without any external electrical field. In this study, it was confirmed that the refractive index state had two stable values depending on domain conditions. This memory effect should be useful for innovative optical switch or scanner in the future.
Epitaxaially-grown KNbO3 thick films over 8 μm in thickness were successfully grown at 220 °C for 6 h on (100)cSrRuO3//SrTiO3 substrates by a hydrothermal method. Epitaxial SrRuO3 layers grown on (100)cSrTiO3 substrates by sputter method were used as bottom electrode layers. Relative dielectric constant and the dielectric loss were 530 and 0.11, respectively. Clear hysteresis loops originated to the ferreoelectricity were observed and a remanent polarization was 25 μC/cm2 at a maximum applied electric field of 540 kV/cm. In addition, the hydrothermal KNbO3 thick film was able to transmitting and receiving of ultrasonic waves over 50MHz.
Deposition of thin films via hydrothermal method has various advantages: low deposition temperature, high purity, deposition on a three-dimensional structure,and a large thickness. Although an epitaxial lead zirconate titanate (PZT) thin-film deposition has been reported, the ferroelectric measurement has not been conducted due to the peel-off morphology of the film. The current paper investigates the improvement of an epitaxial PZT thin film deposited via a hydrothermal method. By adjusting the position at which the substrate was suspended in the solution, smooth morphology surface was successfully obtained. As a bottom electrode, a 200-nm SrRuO3 thin film was deposited on SrTiO3 single crystals, and the PZT thin film was deposited on SrRuO3. The remanent polarization 2Pr and coercive electric field for PZT on SrRuO3/SrTiO3 (001) were 17.1 μC/cm2 and 36 kV/cm, respectively, and those of PZT on SrRuO3/SrTiO3 (111) were 32.7 μC/cm2 and 59 kV/cm, respectively. The reason for large imprint electrical field, 91 kV/cm and 40 kV/cm for each film, was unclear at this stage, although it is associated with self–alignment poling direction. This self–alignment poling direction was confirmed via scanning nonlinear dielectric microscopy and is thought to have been related to the deposition mechanisms.
A hydrothermal method is a unique method to deposit ferroelectric thin films utilizing chemical reaction in solutions. In addition to the low reaction temperature below 200°C, its simple process procedure, automatically aligned polarization and a three-dimensional deposition are advantages. In this study, a lead titanate epitaxial thin film was obtained on a strontium ruthenate bottom electrode sputterd on strontium titanate (100). The highresolution X-ray diffraction mapping showed the film was perfectly c-axis oriented. The transmission electron microscope observation revealed that the film had no lattice dislocation at the interface between lead titanate and strontium ruthenate. A remanent polarization of 96.5μC/cm2 was measured with the single crystal-like DE hysteresis curve. The observation of a scanning nonlinear dielectric microscopy indicated that this film did not contain any defect such as an a-domain and a grain boundary even on the nano scale. With various pulse parameters, nano-domain dots were patterned and the minimum dot radius of inverted domain was 12 nm corresponding to data storage density of 1Tbit/inch2.
Hydrothermal method has various advantages; low deposition temperature, high-purity, deposition on a three-dimensional structure and a large thickness. Although epitaxial PZT thin film deposition has reported, ferroelectric measurement has not been conducted due to the peel-off morphology of the film. The present paper investigates the improvement of an epitaxial PZT thin film deposited via a hydrothermal method. By adjusting the position at which the substrate was suspended in the solution, smooth morphology surface was successfully obtained. As a bottom electrode, 200 nm SrRuO3 thin film was deposited on SrTiO3 single crystals, and the PZT thin was deposited on SrRuO3. The remanent polarization 2Pr for PZT on SrRuO3/SrTiO3 (001) was 19.5 μC/cm2 and that of PZT on SrRuO3/SrTiO3 (111) was 37.2 μC/cm2 respectively. The self alignment poling direction was confirmed via scanning nonlinear dielectric microscopy and is thought to have been related to the deposition mechanisms.
It is well known that spontaneous polarization of ferroelectric material is an intrinsic property applied for nonvolatile memory devices. Poling direction can be reversed in a nanometer size area using the conductive cantilever of a scanning probe microscope. In order to detect nanodots patterns, scanning nonlinear dielectric microscope (SNDM) is superior to piezore-sponse microscope in terms of resolution. In this paper, a real-time measuring method of a poling direction is proposed. Using this method, the domain reversal process was observed and an unexpected phenomenon was found, namely, that the poling directions were aligned antiparallel to the poling electric field. This antiparallel poling reversal took place when the film thickness was more than 350 nm in the case of lithium tantalate. At present, the reason and mechanism of the antiparallel poling reversal are uncertain, although it might be related to the concentrated electric field near the cantilever tip.
Email your librarian or administrator to recommend adding this to your organisation's collection.