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A 62-year-old man presented at our hospitalwith generalfatigue and tarry stool. Gastrointestinalendoscopy revealed a tumor in the first portion of the duodenum. Histologically, biopsy specimens indicated adenocarcinoma, and a subtotal stomach- preserving pancreatoduodenectomy was performed. The finalhistol ogicaldiagnosis was mixed adenoneuroendocrine carcinoma(MANEC)of the duodenum. Liver metastases appeared rapidly within 3 months after surgery. We report on the management of a rare case of MANEC in the duodenum.

Introduction A recent increase in cases of advanced maternal age in the US has been partly associated with a higher incidence of pregnancy-related complications and infertility. However, little is known on how such social changes may have influenced obstetrics articles published in high-impact medical journals subscribed by diverse physicians. The objective of this study is to elucidate the presence and trend of obstetrics investigations in high-profile medical journals. Material and methods This bibliometric study retrospectively analyzed original articles published in the Journal of the American Medical Association (JAMA) from 1997 to 2016. Two reviewers extracted obstetrics articles from PubMed, assessed whether to include specific articles, and categorized them by subtopic. Main outcomes measure was the annual number of original investigations in obstetrics divided by that of original investigations from all fields during the study period, expressed as a trend. Results A total of 3486 original investigations were published during the study period. Regarding obstetrics, 1989 articles were originally extracted from PubMed; after a two-step review process, 199 (10.0%) obstetrics-related original investigations remained. Among them, 134 (67.4%) were classified as pregnancy-related abnormalities or complications (non-infection). The proportion of obstetrics articles decreased during the first 10 years but increased in the last 10 years. The highest figures in the first 10 and last 10 years were 8.5% in 1999 and 9.4% in 2014, respectively, whereas the lowest was 1.4% in 2008. The proportion articles on pregnancy-associated complications or abnormalities (non-infection) steadily increased during the study period, that of articles on infertility increased, and that of articles on human immunodeficiency virus (HIV) infection steadily decreased. Conclusions The observed trend may suggest a changing interest in obstetrics investigations among general physicians in the last 20 years. What is particularly notable is a heightened presence of research on pregnancy-related complications and infertility, which may reflect an increasing frequency in advanced maternal age in the US.

A sub-THz second harmonic multi-frequency gyrotron with Gaussian beam output is under development. This gyrotron can change the frequency stepwise in the range from 270 to 420 GHz. For multi-frequency Gaussian-beam output, all design modes should be converted to Gaussian beams with one mode converter. To achieve this, nine oscillation modes with close values of the transverse propagation angle were selected. Oscillation test of the selected modes was carried out with a linear type gyrotron equipped with the designed cavity. Oscillations of seven second-harmonic modes were successfully observed among the nine selected modes. Operation condition for each mode was experimentally investigated. An internal mode converter to radiate Gaussian beam from each mode was designed.

A two-cavity configuration was introduced in order to increase the number of operating frequencies and to decrease their frequency intervals in a multi-frequency gyrotron. Each cavity has a series of oscillation modes, which can be chosen with the cyclotron frequencies of injected electron beams. The experimental observations have shown that the different oscillation modes for each cavity can be selectively excited according to the changes in the magnetic field strength in the cavity. The frequency step tuning with fundamental harmonic oscillations in a frequency range from 180 to 220-GHz has been demonstrated. The obtained results suggest a further multiple-frequency operation is possible with multiply connected cavities.

Riverbank soil ecosystems are important zones in terms of transforming inorganic nitrogen (N), particularly nitrate (NO3−-N), in soils to nitrous oxide (N2O) gases. Thus, the gasification of N in the riverbank soil ecosystems may produce a greenhouse gas, N2O, when the condition is favourable for N2O-producing microbes. One of the major N2O-producing pathways is denitrification. Thus, we investigated the denitrification potentials along Shibetsu River, Hokkaido, Japan. We sampled riverbank soils from eight sites along the Shibetsu River. Their denitrification potentials with added glucose-carbon (C) and NO3−-N varied from 4.73 to 181 μg·N·kg−1·h−1. The increase of the denitrification after the addition of C and N was negatively controlled by soil pH and positively controlled by soil NH4+-N levels. Then, we investigated the changes in 16S rRNA bacterial community structures before and after an anaerobic incubation with added C and N. We investigated the changes in bacterial community structures, aiming to identify specific microbial species related to high denitrification potentials. The genus Gammaproteobacteria AeromonadaceaeTolumonaswas markedly increased, from 0.0 ± 0.0% to 16 ± 17%, before and after the anaerobic incubation with the excess substrates, when averaged across all the sites. Although we could not find a significant interaction between the denitrification potential and the increase rate of G. AeromonadaceaeTolumonas, our study suggested that along the Shibetsu River, bacterial response to added excess substrates was similar at the genus level. Further studies are needed to investigate whether this is a universal phenomenon even in other rivers.

A second-harmonic frequency step-tuning gyrotron is under development. The oscillation frequencies are separated by approximately 15-GHz steps in a range from 270 to 420-GHz. The operation modes were selected to convert into Gaussian like radiations by one internal mode converter. A triode electron gun was designed in order to operate in a wide range of magnetic fields. The oscillation tests were initiated with a demountable-type axial output tube with no mode-converter. All modes were successfully excited with the designed frequencies.

Frequency tunability in multi frequency bands was experimentally demonstrated in Gyrotron FU CW XA. Frequency tunable modes were searched for with measurement of the radiation pattern outside the vacuum window of the gyrotron with no mode converter. The frequency variation is due to the gyro-BWO mechanism and the same radiation pattern is kept within a finite range of the magnetic field for each oscillation mode. Five transverse modes showing the frequency variation more than 1 GHz were obtained.

Despite an increase in the number of physicians in Japan, misdistribution of physicians within the 47 prefectures remains a major issue. Migration of physicians among prefectures might partly explain the misdistribution. However, geographical differences and the magnitude of physicians' migration are unclear. The aim of this study was to estimate the extent of migration of physicians among prefectures and explore possible factors associated with physicians' migration patterns.Using a publicly available government database from 1995 to 2014, a quantitative estimation of physicians' migration after graduation from a medical school was performed. The inflow and outflow of physicians were ostensibly calculated in each prefecture based on the differences between the number of newly licensed physicians and the actual number of practicing physicians after an adjustment for the number of deceased or retired physicians. Simple and multiple linear regression analyses were conducted to examine socio-demographic background factors.During the 20-year study period, the mean annual numbers of newly licensed physicians, deceased or retired physicians, and increase in practicing physicians in the whole country were 7416, 3382, and 4034, respectively. Among the 47 prefectures, the median annual number of newly licensed physicians to 100,000 population ratio (PPR) was 6.4 (range 1.5-16.5), the median annual adjusted number of newly licensed physicians was 61 (range, -18 to 845; the negative and positive values denote outflow and inflow, respectively), whereas the median annual number of migrating physicians was 13 (range, -171 to 241). The minimum and maximum migration ratios observed were -68% and 245%, respectively. In the final regression model of the 8 variables examined, only "newly licensed PPR" remained significantly associated with physician's migration ratios.A significant inequality in the proportion of the migration of physicians among prefectures in Japan was observed. The multivariate analyses suggest that the newly licensed PPRs, and not from-rural-to-urban migration, might be one of the keys to explaining the migration ratios of physicians. The differences and magnitude of physicians' migration should be factored into mitigate misdistribution of physicians.

We report the strong yellow emission of bulk ZnO single crystals irradiated with the high-power gyrotron beam. Hydrothermally grown bulk crystals with high conductivity are irradiated at room temperature with up to 60-W output of a sub-terahertz gyrotron wave source. During gyrotron irradiation, the high-conductivity crystals exhibit intense emissions with a peak of around 2 eV (600 nm) and a longer-wavelength tail. The sample temperatures were also elevated from room temperature to above 1000 K by irradiation. However, when heated up to 1250 K using a heater without irradiation, the ZnO crystals do not exhibit similar visible emissions. We then use the generalized Planck's radiation in non-equilibrium states as an explanation of our experimental observations. The emission peak intensity can be enhanced by the gyrotron-induced non-equilibrium states, and the emission peak position can be related to the Urbach energy. With high intensities in the visible wavelengths, the emissions of the irradiated crystal...

We appreciate the interest in our publication1 and the Dr J. Joe’s case report similar to our patient, in which stenosis and occlusion of extracranial and intracranial arteries caused transient ischemic attack as an initial symptom. Differential diagonoses of Takayasu arteritis (TAK) …

This paper proposes and verifies a prediction market system for obtaining a forecast distribution of the demand quantity for a certain product in a future time period based on the collective knowledge of employees or customers themselves of a company. It first introduces a new type of prediction securities called the self-adjustable interval prediction securities (SIPS); SIPS are a set of winner-takes-all type contracts and each of which is tied to the future event that the actual demand quantity is included in a certain interval. The prediction intervals are mutually exclusive and collectively cover the whole feasible region of the demand quantity. What is unique to SIPS is that how the whole feasible region is partitioned into a set of prediction intervals is dynamically and adaptively self-adjusted so as to improve the accuracy of the output forecast distribution. It next generalizes the logarithmic market scoring rule (LMSR), which is one of the most popular market making algorithms for a prediction market, to SIPS. The paper also tests how the proposed prediction market system works in a laboratory setting and confirms that SIPS outperform the fixed interval prediction securities (FIPS) in terms of the accuracy of the output forecast distribution.