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We analysed associations between exposure to nightlife businesses and severe acute respiratory syndrome coronavirus 2 PCR test results at a tertiary hospital in Tokyo between March and April 2020. A nightlife group was defined as those who had worked at or visited the businesses. We included 1517 individuals; 196 (12.9%) were categorised as the nightlife group. After propensity score matching, the proportion of positive PCR tests in the nightlife group was significantly higher than that in the non-nightlife group (nightlife, 63.8%; non-nightlife, 23.0%; P < 0.001). An inclusive approach to mitigate risks related to the businesses needs to be identified.
The objective of this study was to explore factors associated with hara-kiri as a method of suicide and suicidal behavior in contemporary Japan.
A retrospective study was conducted on medical records of 421 patients (174 male; 247 female) who were considered suicidal and treated at the Kitasato University Hospital Emergency Medical Center in Japan between January 2006 and March 2008. We compared hara-kiri and all other methods regarding sociodemographics and clinical features of all suicidal patients.
Instances of hara-kiri suicide attempt had the highest proportion of males (63%) among all suicide and suicidal behavior. One-way analysis of variance revealed significant differences between hara-kiri and other suicide attempt methods in the age of the suicidal patients. Result of multiple logistic regression analysis indicated that those who attempted hara-kiri suicide were likely to be male, be diagnosed with schizophrenia, survive, and be married.
Our findings indicate that hara-kiri as a method of suicide and suicidal behavior remain prevalent in Japan, and the study findings also suggest that both clinical and cultural factors might play a role in hara-kiri as a method of suicide and suicidal behavior.
Altered levels of phenylalanine and its metabolites in blood and cerebrospinal fluid have previously been reported in schizophrenia. This study attempted to examine whether phenylalanine kinetics is altered in schizophrenia using the 13C-phenylalanine breath test (13C-PBT).
Subjects were 20 patients with schizophrenia and the same number of controls. 13C-phenylalanine was administered and then 13CO2 concentration in breath was monitored for 120 minutes. The Δ 13CO2 at each collecting time, the maximal Δ 13CO2 (Cmax), the time to reach Cmax (Tmax), the area under the curve of time course of Δ13CO2 (AUC), the cumulative recovery rate (CRR) at each collecting time of the 13C-PBT were calculated for each subject.
Body weight (BW) and diagnostic status were significant predictors for Cmax. BW, age and diagnostic status were significant predictors for AUC and CRR at 120 minutes (CRR0-120). A repeated measures ANCOVA controlling for age and BW revealed a different pattern of change in CRR over time between the patients and controls and that Δ13CO2 in schizophrenia were lower than that in healthy control at all sampling point during 120 min, with an overall significant differences between healthy control and schizophrenia. The ANCOVA controlling for age and BW, showed that Cmax, AUC and CRR0-120 were significantly lower in schizophrenics than in controls.
Our data indicate the different change of Δ13CO2 and CRR over time and the decreased Cmax, AUC and CRR0-120 of 13C-PBT in schizophrenia patients compared to healthy controls, suggesting the altered phenylalanine kinetics in schizophrenia.
The implementation of advanced multi-level modulation schemes such as quadrature phase-shift keying (QPSK) in contrast to the conventional on–off keying is crucial to further boost the terahertz (THz) communications speed. Thereby, carrier phase noise reduction in the THz range is one of the key goals that need to be urgently achieved. In this paper, the photonic-based THz sources and the phase noise problem are briefly summarized. Then, a low phase-noise photonic source based on the stimulated Brillouin scattering (SBS) optical fiber cavity is first applied for a 300-GHz-band QPSK wireless communication link. The highest data rate at forward-error-correction limited condition was 15 Gbaud utilizing the SBS-based photonic source with a small transmit power of ~ −36 dBm. Its transmission characteristics are evaluated and compared with the conventional optical frequency comb generator (OFCG)-based source at 5 Gbaud. The proposed SBS-based photonic source has been proven to offer better performances than the OFCG-based source with respect to the phase noise, optical carrier to noise ratio, and bit error rate in communications.
Parotid gland carcinoma is a rare and complicated histopathological classification. Therefore, assembling a sufficient number of cases with long-term outcomes in a single institute can present a challenge.
The medical records of 108 parotid gland carcinoma patients who were treated at Kyushu University Hospital, Fukuoka, Japan, between 1983 and 2014 were reviewed. The survival outcomes were analysed according to clinicopathological findings.
Forty-six patients had low clinical stage tumours (I–II), and 62 patients had high clinical stage tumours (III–IV). Fifty-two, 10 and 46 patients had low-, intermediate- and high-grade tumours, respectively. Twenty-seven of 65 cases had positive surgical margins. In high clinical stage and intermediate- to high-grade tumours, adjuvant radiation therapy was correlated with local recurrence-free survival (p = 0.0244). Intermediate- to high-grade tumours and positive surgical margins were significantly associated with disease-specific survival in multivariate analysis (p = 0.0002 and p = 0.0058).
The results of this study show that adjuvant radiation therapy is useful for improved local control in patients with high clinical stage and intermediate- to high-grade tumours.
Life history traits, such as clutch size, egg size (weight), developmental periods of eggs, and female body (abdomen) size, were investigated in Japanese species of the genus Elasmostethus Fieber (Hemiptera: Acanthosomatidae): E. amabilis Yamamoto, E. brevis Lindberg, E. humeralis Jakovlev, E. interstinctus (Linnaeus), E. kerzhneri Yamamoto, and E. nubilus (Dallas). With the exception of clutch size, significant differences were observed in the traits among species. No species exhibited maternal care of eggs. These data form a solid basis for future comparative analyses in the family Acanthosomatidae, which contains both subsocial and asocial species.
To identify the predictive and prognostic factors associated with ampicillin-resistant enterococcal bacteraemia, we retrospectively reviewed demographic, microbiological and clinical data of patients attending the Kyoto University Hospital, Japan, between 2009 and 2015. Logistic regression and Cox regression analyses were performed to determine the predictive and prognostic factors, respectively. In total, 235 episodes of enterococcal bacteraemia were identified. As ampicillin susceptibility was uniform for Enterococcus faecalis isolates and almost all ampicillin-resistant isolates were E. faecium, bacteraemia due to these species was investigated separately. E. faecalis and E. faecium accounted for 41.7% (98/235) and 48.1% (113/235) of the isolates, respectively and 91.2% of all E. faecium were ampicillin resistant. Nosocomial E. faecium bacteraemia acquisition (odds ratio (OR), 13.6; 95% confidence intervals, 3.16–58.3) was associated with ampicillin-resistant isolates. Bacteraemia from an unknown source (hazard ratio (HR), 2.91; 95% CI 1.36–6.21) and an increased Pitt bacteraemia score (PBS) (HR, 1.36; 95% CI 1.21–1.52) were associated with 30-day mortality in E. faecium infections. Likewise, bacteraemia from an unknown source (HR, 4.17; 95% CI 1.25–13.9) and increased PBS (HR, 1.27; 95% CI 1.09–1.48) were associated with 30-day mortality in patients with E. faecalis bacteraemia. The empirical therapeutic administration of glycopeptides is recommended for patients with bacteraemia from an unknown source in whom severe E. faecium bacteraemia is suspected.
It is thought that protoplanets formed in protoplanetary disks excite the orbital motion of the surrounding planetesimals, and the bow shocks caused by the highly excited planetesimals heat their icy component evaporating into gas. We have performed model calculations to study the evolution of molecular abundances of the evaporated icy component, which suggests sulfur-bearing molecules can be good tracers of icy planetesimal evaporation. Here we report the result of our ALMA observations of sulfur-bearing molecules towards protoplanetary disks. The lines were undetected but the obtained upper limits of the line fluxes and our model calculations give upper limits of the fractional abundances of x(H2S) < 10−11 and x(SO) < 10−10 in the outer disk. These results are consistent with the molecular abundances in comets in our Solar system.
The redshift interval z = 2–3 is known as the cosmic noon that is the most active era of star formation across the Universe (Hopkins & Beacom 2006). In the past decade, many authors have investigated global properties of star-forming (SF) galaxies in this turbulent era, such as gas fractions and gaseous metallicities (e.g. Erb et al. 2006). With those achievements, we are going on to the next stage to understand more details i.e. those physical parameters in star-forming regions. Recent advent of near-infrared instruments typified by MOSFIRE on the Keck telescope, enable us with identifying the physical parameters of Hii regions in ‘typical’ SF galaxies individually (Steidel et al. 2014). Recent highlights suggest higher electron densities, higher ionization parameters, and harder UV radiation fields may be common.
In order to know how galaxy evolution physically correlates with the natures of their star-forming regions, we have explored relationships between the electron density (ne) of ionized gas from the oxygen line ratio and other physical properties, based on the deep spectra of Hα emitters at z = 2.5 by the MOSFIRE. MOSFIRE for the first time provides ne of the galaxies at high-z with a high level of confidence. The result shows the specific star formation rate (sSFR) and the SFR surface density (ΣSFR) are correlated with ne (Shimakawa et al. 2015). The ne-ΣSFR relation could be linked to the star formation law in Hii regions if we assume that hydrogen in Hii regions is fully-ionized. Otherwise, more active star formation per unit area (higher ΣSFRs), may cause higher ionization states. However, we need some specific concerns that obtained physical parameters should depend on the scale dependence, since typical size of Hii region is only <100 pc despite that we study physical states of entire galaxies. Thus we obtain surface-brightness-weighted and ensemble averaged line fluxes for the entire galaxy or the part that falls into the slit width (a few kpc scale size). The thirty meter telescope (TMT) is a powerful instrument to resolve such a difficulty, since its spatial resolution reaches <100 pc on the physical scale at z ~ 2 by AO assistance.
Hyalinizing clear cell carcinoma is a rare minor salivary gland neoplasm. The treatment of choice is surgical resection with or without post-operative radiotherapy. This tumour often demonstrates a good prognosis.
We report a case of hyalinizing clear cell carcinoma arising in the nasopharynx. A 27-year-old female presented with progressive hearing disturbance and tinnitus. On examination, an expansile mass was observed in her nasopharynx. Biopsy was performed and the pathology results returned as clear cell carcinoma.
Results and conclusion:
Surgical resection was performed trans-orally accompanied by trans-palatal approach. She has no recurrence during more than two years of follow up.
At the present moment, zinc oxide is primarily being used as an electronic material for low-field thin-film transistor and transparent conducting oxide device applications. In this paper, we present some recent results on the steady-state electron transport within zinc oxide suggesting that this material may also be considered as an alternative material to gallium nitride for high-power and high-frequency electron device applications. The expected device performance that may be obtained from zinc oxide-based devices is then projected and contrasted with that expected from gallium nitride-based devices. It is shown that zinc oxide-based devices have a slight advantage when compared with the case of gallium nitride.
Due to its wide band-gap, Al2O3 is known to have a moderate leakage current and a good dielectric strength . Moreover, this dielectric has a fair permittivity and so constitutes interesting candidate as dielectric for Metal-Insulator-Metal (MIM) capacitor. Atomic Layer Deposition (ALD) allows obtaining a dense and thin Al2O3 amorphous layer. ALD limits problems of interlayer diffusion because Al2O3 is deposited underneath 400°C  which is essential when MIM are co-integrated with temperature sensitive structures.
The aim of our investigation is to attempt to tie aluminum oxide properties dielectric with reliability from the help of capacitors of the entire wafer. In this way, conduction mechanism analysis and capacitance measurements were statistically led on the wafer. We particularly focus our study on the quantification of defects and their influence on the leakage current in planar capacitor. Firstly, to estimate the fixed oxide charges densities in the bulk of Al2O3 and to analyze conduction mechanism, Metal-Oxide-Semiconductor (MOS) (Al/Al2O3/HR-Si) is developed. Then, a MIM stack (Al/TiN/Al2O3/TiN/HR-Si) is developed in order to evaluate the leakage current and the electrical reliability of thin films Al2O3 based MIM capacitors. Different performances are observed according to the area on the wafer. That could be explained by the quality of the Al2O3 layer and the interfaces between TiN and the oxide.
Indium tin oxide (ITO) nanowires (NWs) were grown on glass substrates by using ITO sputtering sources (targets) with SnO2 contents in the range of approximately 5.0 to 30.0 wt%. NW growth became apparent at temperatures above 125 °C, and the In, Sn and O contents of the resulting ITO NWs were similar to those of the ITO source. NWs grown from ITO sources containing 5.0 to 12.0 wt% SnO2 had circular or elliptical cross-sections, while those obtained from sources with 12.0 to 30.0 wt% SnO2 exhibited square cross-sections. ITO NWs approximately 2 μm in length were obtained as single crystals with a cubic crystal structure. The resistivity of an ITO NW was measured using four nanoprobes in conjunction with a field emission scanning electron microscope and was found to range from 0.13 to 0.6 μΩ-m, values that were approximately one order of magnitude lower than those of transparent ITO films.
The importance of ZnxMg1-xO is increasing day by day because of its wider bandgap than ZnO. This ternary semiconductor finds its application in the fields of optoelectronics, spintronics, superlattices due to its unique blueshifted UV-luminescent property. n- to p-type conduction which is the motive of the project can be achieved with increasing Mg content in ZnMgO. The optical characteristics of the nitrogen doped ZnxMg1-xO (x=0.85) grown on 2 inch Si <100>wafer by RF sputtering are studied and analyzed thoroughly using low temperature (15K) photoluminescence measurements. Nitrogen implantation was carried out by Plasma immersion Ion Implantation technique on the sample. Rapid Thermal Process was employed to remove defects resulting from implantation. The samples were annealed at 700°C, 800°C, 900°C, and 1000o C for 10 seconds in an oxygen ambient. Photoluminescence (PL) measurements were performed at low temperature (15K) which exhibited acceptor-bound-exciton peak (A°X) and donor-bound-acceptor pair (DAP) at 3.336 eV and 3.236 eV respectively. At 3.364 eV, S peak was found for the sample annealed at 800°C after implantation. This peak was attributed to the existence of ZnO-like composition. Localized and de-localized exciton peaks were found around 3.42 and 3.45 eV respectively. This result is very important because though dominant acceptor peak was not found but proper optimization of the parameters can lead to p-type ZnMgO which is the main motive of this project.
A high gain ZnO nanowire (NW) based photodetector was fabricated, which was sensitive to photoexcitation at or below 370 nm corresponding to the band-edge of ZnO. At an incident wavelength of 370 nm and a bias field of 5 kV/cm, the maximum responsivity was over 105 A/W corresponding to an extremely high photoconductive gain of the order of 106. Through this work we provide experimental evidence of the role of surface and defects in carrier dynamics, resulting in enhanced photoresponse. Using intensity and temperature dependence of the rise and decay rates of photocurrent, we present a detailed analysis that provides an estimate of the activation energies of carrier trapping mechanisms.
The role of ferroelectric LiNbO3 (LNB) in altering the frequency dependence of the capacitance of CaCu3Ti4O12 (CCTO) thin films has been investigated. A cost effective spin coating deposition process was used to integrate the oxide heterostructures onto silicon substrates. This study showed that the frequency stability of the CCTO/LNB structure was much improved when the crystallization conditions and physical dimension of each layer were optimized. To integrate this structure with current silicon technology, heterostructures of CCTO and LNB thin films were fabricated on HF terminated Si using chemical solution deposition. It was found that the order of deposition of the two layers was important for the structural quality of the heterostructures with the CCTO layer followed by the LNB layer being the preferred structure. In addition to improvement of the capacitance variation with frequency, the heterostructures also provide a path to tuning the frequency of operation.