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We study the dynamics of turbulence transport subject to a constraint on the profile formation and relaxation, dominated by the ion temperature gradient modes, within the framework of adiabatic electron response using a flux-driven global gyro-kinetic toroidal code, GKNET. We observe exponentially constrained profiles, with two different scale lengths, that are spatially constant in each region in higher input power regimes. The profiles are smoothly connected in the knee region located at 1 / 2 − 2 / 3 of the minor radius, outside which the gradient is steepened and shows a weak confinement improvement. Based on the probability density function analysis of heat flux eddies, the power law demonstrates a dependence on the eddy size S , as P ∼ S − α , which distinguishes events into diffusive and non-diffusive parts including the validation of quasi-linear hypotheses. Radially localized avalanches and global bursts, which exhibit different spatial scales, play central roles in giving rise to constrained profiles on an equal footing. It is also found that the E × B shear layers are initiated by the global bursts, which evolve downward on a slow time scale across the knee region and play a role in adjusting the profile by increasing the gradient. This article is part of a discussion meeting issue ‘H-mode transition and pedestal studies in fusion plasmas’.

Nonlinear saturation mechanism of ion-temperature-gradient turbulence at finite normalized pressure is identified by analysis of the nonlinear entropy transfer in global gyrokinetic simulations of the turbulence. Turbulence at such finite normalized pressure is electromagnetic and often exhibits non-saturation due to a lack of zonal flows by the influence of magnetic fluctuations of the turbulence in local gyrokinetic simulations. The present study identifies a new saturation mechanism caused by global entropy transfer due to turbulent E × B flow convection in real space. The convection of the entropy associated with the turbulence in the radial direction produces global zonal flows at the both sides of the most active region of the turbulence to avoid the effect of the magnetic fluctuations, and then global zonal-flow excitation is not suppressed, leading to a steady state of the turbulence.

We present the results of a time-coincident event search for low-energy electron antineutrinos in the KamLAND detector with gamma-ray bursts from the Gamma-ray Coordinates Network and Fermi Gamma-ray Burst Monitor. Using a variable coincidence time window of $\pm$500s plus the duration of each gamma-ray burst, no statistically significant excess above background is observed. We place the world's most stringent 90% confidence level upper limit on the electron antineutrino fluence below 17.5 MeV. Assuming a Fermi-Dirac neutrino energy spectrum from the gamma-ray burst source, we use the available redshift data to constrain the electron antineutrino luminosity and effective temperature., 9 pages, 3 figures

Background Over 30% of the population of Okinawa Prefecture have a high body mass index. The incidence of hypertension and dyslipidaemia has also increased in recent years. We found that Ooitabi (Ficus pumila L.), a plant native to Okinawa, was useful for hypertension. During ancient times, the extracts of Ooitabi leaves were used for making Ishimaki tea in some areas of Okinawa Prefecture. The plants in Okinawa are rich in antioxidants, and four flavonoid glycosides, including rutin, have been identified in Ooitabi. Methods In the present study, we conducted clinical verification tests on the effects of drinking Ishimaki tea on outpatients with hypertension and dyslipidaemia. Of 3814 Japanese patients who underwent medical check‐ups in Okinawa, 38 individuals with high blood pressure, dyslipidaemia, liver dysfunction and gout visited our hospital as outpatients and were asked to drink Ishimaki tea. Results After 3 months, there were significant reductions in body mass index, systolic and diastolic blood pressure, total cholesterol, low‐density lipoprotein cholesterol, γ‐glutamyltrans peptidase, uric acid and ratio of blood vessel insulin resistance. Conclusions Ooitabi extract can lower blood pressure and improve lipid abnormalities and has likely contributed to the well‐known health and longevity of the population in Okinawa., Shisa is Okinawan lion (or lion dog) statue placed as talisman against evil at entrances, on roofs and on stone walls. Shisa holds Ooitabi leaves in its mouth (Fig. 2a).

We report on a search for electron antineutrinos ($\bar{\nu}_e$) from astrophysical sources in the neutrino energy range 8.3 to 30.8 MeV with the KamLAND detector. In an exposure of 6.72 kton-year of the liquid scintillator, we observe 18 candidate events via the inverse beta decay reaction. Although there is a large background uncertainty from neutral current atmospheric neutrino interactions, we find no significant excess over background model predictions. Assuming several supernova relic neutrino spectra, we give upper flux limits of 60--110 cm$^{-2}$ s$^{-1}$ (90% CL) in the analysis range and present a model-independent flux. We also set limits on the annihilation rates for light dark matter pairs to neutrino pairs. These data improves on the upper probability limit of $^{8}$B solar neutrinos converting into $\bar{\nu}_e$'s, $P_{\nu_e \rightarrow \bar{\nu}_e} < 3.5\times10^{-5}$ (90% CL) assuming an undistorted $\bar{\nu}_e$ shape. This corresponds to a solar $\bar{\nu}_e$ flux of 60 cm$^{-2}$ s$^{-1}$ (90% CL) in the analysis energy range., Comment: 21 pages, 9 figures, 4 tables, accepted for publication in Astrophysical Journal

We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218±9 μs. We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218 \pm 9 \mu s.

A glass gas electron multiplier (GEM) was tested to evaluate performance for charged particle spectroscopy in a gas chamber. The test was done with varying low-pressure Ar/CH4 mixture gas (9:1, P-10) for evaluation of effective electron multiplication gain (gas gain) with the relationship between supplied voltage to GEM (GEM ΔV), energy and timing resolution of signals. The GEM ΔV is parameterized as a function of gas gain and pressure from experimental results. The signal-to-noise ratio on the anode signal was significantly improved due to electron multiplication by the glass GEM in comparison with traditional grid gas ionization chamber. A test using Ar/CO2 mixture gas (9:1) shows that GEM ΔV is successfully reduced with keeping gas gain and energy resolution comparable. Time difference between anode and cathode signals behaves reasonably with drift time of initial electrons. We conclude that charged particle spectrometer using glass GEM can be designed by using obtained parameter. The spectrometer is useful especially for low energy charged particle due to the gas gain.

We present the results of a search for core-collapse supernova neutrinos, using long-term KamLAND data from 2002 March 9 to 2020 April 25. We focus on the electron antineutrinos emitted from supernovae in the energy range of 1.8--111 MeV. Supernovae will make a neutrino event cluster with the duration of $\sim$10 s in the KamLAND data. We find no neutrino clusters and give the upper limit on the supernova rate as to be 0.15 yr$^{-1}$ with a 90% confidence level. The detectable range, which corresponds to a >95% detection probability, is 40--59 kpc and 65--81 kpc for core-collapse supernovae and failed core-collapse supernovae, respectively. This paper proposes to convert the supernova rate obtained by the neutrino observation to the Galactic star formation rate. Assuming a modified Salpeter-type initial mass function, the upper limit on the Galactic star formation rate is, 10 pages, 4 figures, accepted for publication in Astrophysical Journal

We report the result of a search for neutrinos in coincidence with solar flares from the GOES flare database. The search was performed on a 10.8 kton-year exposure of KamLAND collected from 2002 to 2019. This large exposure allows us to explore previously unconstrained parameter space for solar flare neutrinos. We found no statistical excess of neutrinos and established 90% confidence level upper limits of $8.4 \times 10^7$ cm$^{-2}$ ($3.0 \times 10^{9}$ cm$^{-2}$) on electron anti-neutrino (electron neutrino) fluence at 20 MeV normalized to the X12 flare, assuming that the neutrino fluence is proportional to the X-ray intensity., 13 pages, 9 figures, accepted October 27, 2021

Summary Background & aims The associations between dietary magnesium intake and stroke and coronary heart disease (CHD) incidences are inconsistent and not established in Asian. We aimed to determine the association between dietary magnesium intake and the risk of stroke and CHD in a Japanese population. Subjects/Methods We studied 85,293 Japanese subjects by questionnaire at baseline (age 45–74 years, without cardiovascular disease or cancer in 1995 and 1998 for Cohorts I and II, respectively). The participants were followed until the end of 2009 and 2010 in Cohorts I and II, respectively. Dietary magnesium intake was estimated from a self-administered 138-item food-frequency questionnaire. Results After 1,305,738 person-years of follow-up, 4110 strokes and 1283 cases of CHD were documented. The multivariable-adjusted hazard ratios (HRs, 95% confidence intervals, 95%CIs) of CHD for the fourth and fifth quintiles of dietary magnesium intake were 0.70 (0.50–0.99) and 0.66 (0.44–0.97) in men (P for trend = 0.036), respectively, and third quintile of dietary magnesium intake was 0.61 (0.39–0.96) in women (P for trend = 0.241), compared with the lowest quintile in men and women. We observed no decreased risks of incident stroke in men or women with higher dietary magnesium intakes. Conclusions Higher dietary magnesium intake was associated with a reduced risk of CHD in Japanese men.

A finding between dietary pattern and cancer may provide visions beyond the assessment of individual foods or nutrients. We examined the influence of dietary pattern with colorectal cancer (CRC) among a Japanese population.A total of 93,062 subjects (43,591 men, 49,471 women) who participated in the Japan Public Health Center-based Prospective Study were followed from 1995-1998 to the end of 2012, during which 2482 cases of CRC (1514 men, 968 women) were newly identified. Dietary data was obtained from a validated food-frequency questionnaire between 1995 and 1998.Three dietary pattern was derived from principal components factor: prudent, westernized, and traditional pattern. After controlled for potential confounders, the prudent pattern showed a decreased association of CRC risk in men (HR for highest quintile vs lowest: 0.85; 95% CI: 0.72-1.00; P trend0.05), slightly more strongly with distal colon cancer (P trend0.05); but an increased risk of rectal cancer in women (P trend0.05). The westernized pattern showed a significant positive linear trend for colon (P trend0.05) and distal cancer (P trend0.05) in women. There was no apparent association of traditional Japanese dietary pattern on the overall or any specific sites risk of CRC.A prudent dietary pattern showed an inverse association with CRC risk in men, and a westernized pattern was related with a higher risk of colon and distal cancer in women.

It is commonly considered that frost damage is caused by sudden freezing of supercooled water, which is a random phenomenon. Therefore, the aims of this study are to establish a prediction model for the probability of freezing until any lowest reached temperature, and to obtain the probability distribution function of the freezing point for the proposed analytical prediction model. First, theoretical prediction model for the probability of the instantaneous increment of ice content when lowest achieving temperature was known was derived based on these assumptions that building structure is an aggregation of small elements. Next, the freezing point measurement was carried out by using saturated mortar samples as the small element. As the results, it could be found that the first freezing due to supercooling occurred from -4 to -11 deg. C and the maximum probability was appeared at -7.5 deg. C. The average increment of ice content at every temperature closed to the 40 % volume of pore water until the thermodynamically-based freezing point. Moreover, the proposed method that can calculate the probability distributions of the instantaneous increment of ice content for any lowest achieving temperature from pore size distribution had good agreements with the measurement results.

Aims Coping strategies may be significantly associated with health outcomes. This is the first study to investigate the association between baseline coping strategies and cardiovascular disease (CVD) incidence and mortality in a general population cohort. Methods and results The Japan Public Health Center-based prospective Study asked questions on coping in its third follow-up survey (2000–04). Analyses on CVD incidence and mortality included 57 017 subjects aged 50–79 without a history of CVD and who provided complete answers on approach- and avoidance-oriented coping behaviours and strategies. Cox regression models, adjusted for confounders, were used to determine hazard ratios (HRs) according to coping style. Mean follow-up time was 7.9 years for incidence and 8.0 years for mortality. The premorbid use of an approach-oriented coping strategy was inversely associated with incidence of stroke (HR = 0.85; 95% CI, 0.73–1.00) and CVD mortality (HR = 0.74; 95% CI, 0.55–0.99). Stroke subtype analyses revealed an inverse association between the approach-oriented coping strategy and incidence of ischaemic stroke (HR = 0.79; 95% CI, 0.64–0.98) and a positive association between the combined coping strategy and incidence of intra-parenchymal haemorrhage (HR = 2.03; 95% CI, 1.01–4.10). Utilizing an avoidance coping strategy was associated with increased mortality from ischaemic heart disease (IHD) only in hypertensive individuals (HR = 3.46; 95% CI, 1.07–11.18). The coping behaviours fantasizing and positive reappraisal were associated with increased risk of CVD incidence (HR = 1.24; 95% CI, 1.03–1.50) and reduced risk of IHD mortality (HR = 0.63; 95% CI, 0.40–0.99), respectively. Conclusion An approach-oriented coping strategy, i.e. proactively dealing with sources of stress, may be associated with significantly reduced stroke incidence and CVD mortality in a Japanese population-based cohort.

The Super Kamiokand-Gadolinium (SK-Gd) project is the upgrade of the Super-Kamiokande (SK) detector in order to discover Supernova Relic Neutrinos (SRNs) by loading 0.2% of Gd2(SO4)3 into a 50 kton of the SK water tank. In order to continue solar neutrino measurement with low energy threshold at ∼3.5 MeV, main radioactive contamination, U and Th in Gd2(SO4)3, should be purified before loading. We developed solid-phase extraction technique to measure low concentration of U and Th in Gd2(SO4)3 by ICP-MS. The extraction technique and current status will be presented.

Background and aims Higher intake of fish or n-3 polyunsaturated fatty acids (PUFAs) has been associated with reduced risk of coronary heart disease (CHD). However, it is unclear whether increased blood levels of n-3 PUFAs are associated with reduced risk of CHD in the Japanese population. Methods The relationship between circulating levels of n-3 PUFAs (eicosapentaenoic acid + docosapentaenoic acid + docosahexaenoic acid) and risk of CHD was examined in a nested case-control study among participants in the Japan Public Health Center (JPHC)-based Study Cohort. Plasma n-3 PUFA phospholipid levels were measured at baseline by gas chromatography in 209 cases with CHD and 418 controls matched for sex, age, date of blood draw, time elapsed since last meal before blood collection, and study location. The CHD cases (n = 209) comprised 168 cases of myocardial infarction and 41 of sudden cardiac death, otherwise classified as 157 non-fatal and 52 fatal coronary events, respectively. Mean duration of follow-up was 13.5 years. Results Multivariate conditional logistic analysis showed no significant association between n-3 PUFAs and risk of total CHD. The odds ratio (OR) for the highest versus lowest quartiles of plasma n-3 PUFAs was 0.79 (95% confidence interval [95% CI]: 0.41–1.51, p for trend = 0.51). Subtype analysis of CHD revealed that the multivariate ORs for the highest versus lowest quartiles for n-3 PUFAs were 0.91 (95% CI: 0.43–1.89, p for trend = 0.90) for myocardial infarction, 0.08 (95% CI: 0.01–0.88, p for trend = 0.04) for sudden cardiac death, 0.89 (95% CI: 0.42–1.89, p for trend = 0.97) for nonfatal coronary events, and 0.12 (95% CI: 0.02–0.75, p for trend = 0.03) for fatal coronary events. Conclusions Plasma n-3 PUFA levels were not associated with risk of total CHD but were inversely associated with risks of sudden cardiac death and fatal coronary events among middle-aged Japanese individuals.

The ^{181}Ta quadrupole resonance [nuclear quadrupole resonance (NQR)] technique is utilized to investigate the microscopic magnetic properties of the Weyl semimetal TaP. We find three zero-field NQR signals associated with the transition between the quadrupole split levels for Ta with I=7/2 nuclear spin. A quadrupole coupling constant, ν_{Q}=19.250 MHz, and an asymmetric parameter of the electric field gradient, η=0.423, are extracted, in good agreement with band structure calculations. In order to examine the magnetic excitations, the temperature dependence of the spin-lattice relaxation rate (1/T_{1}T) is measured for the f_{2} line (±5/2↔±3/2 transition). We find that there exist two regimes with quite different relaxation processes. Above T^{*}≈30 K, a pronounced (1/T_{1}T)∝T^{2} behavior is found, which is attributed to the magnetic excitations at the Weyl nodes with temperature-dependent orbital hyperfine coupling. Below T^{*}, the relaxation is mainly governed by a Korringa process with 1/T_{1}T=const, accompanied by an additional T^{-1/2}-type dependence to fit our experimental data. We show that Ta NQR is a novel probe for the bulk Weyl fermions and their excitations.

Senescence marker protein-30 (SMP30) decreases androgen-independently with aging and is a lactone-hydrolyzing enzyme gluconolactonase (GNL) that is involved in vitamin C biosynthesis. In the present study, bone properties of SMP30/GNL knockout (KO) mice with deficiency in vitamin C synthesis were investigated to reveal the effects of SMP30/GNL and exogenous vitamin C supplementation on bone formation. Mineral content (BMC) and mineral density (BMD) of the mandible and femur of SMP30/GNL KO and wild-type mice at 2 and 3 months of age with or without vitamin C supplementation were measured by dual-energy X-ray absorptiometry. Body and bone weight of both age groups decreased and became significantly lower than those of wild-type mice. The bones of SMP30/GNL KO mice were rough and porous, with BMC and BMD significantly below wild-type. Oral supplementation with vitamin C eliminated differences in body weight, bone weight, BMC, and BMD between SMP30/GNL KO and wild-type mice at each age. These results indicate that bone degeneration in SMP30/GNL KO mice was caused by lack of vitamin C, and that this mouse strain is an appropriate model for bone metabolism in humans, which have no ability to synthesize vitamin C.

Background We sought to elucidate the effect of an ascorbic acid (AA) deficiency on gene expression, because the water soluble antioxidant AA is an important bioactive substance in vivo. Methods We performed microarray analyses of the transcriptome in the liver from senescence marker protein-30 (SMP30)/gluconolactonase (GNL) knockout (KO) mice, which are unable to synthesize AA in vivo. Results Our microarray analysis revealed that the AA deficiency increased gene expression related to the oxidation–reduction process, i.e., the nuclear factor, erythroid derived 2, like 2 (Nrf2) gene, which is a reactive oxygen species-sensitive transcriptional factor. Moreover, this AA deficiency increased the expression of genes for lipid metabolism including the cytochrome P450, family 7, subfamily a, polypeptide 1 (Cyp7a1), which is a late-limiting enzyme of the primary bile acid biosynthesis pathway. Although an AA deficiency increased the Cyp7a1 protein level, bile acid levels in the liver and gallbladder decreased. Since Cyp7a1 has a heme iron at the active site, AA must function as a reductant of the iron required for the continuous activation of Cyp7a1. Conclusions This experimental evidence strongly supports a role for AA in the physiologic oxidation–reduction process and lipid metabolism including bile acid biosynthesis. General significance Although many effects of AA supplementation have been reported, no microarray analysis of AA deficiency in vivo is available. Results from using this unique model of AA deficiency, the SMP30/GNL-KO mouse, now provide new information about formerly unknown AA functions that will implement further study of AA in vivo.

Seafood/fish intake has been regarded as a protective factor for coronary heart disease (CHD), while smoking is a strong risk factor. To examine whether associations between smoking and risk of CHD are modified by seafood/fish intake, we studied 72,012 Japanese men and women aged 45-74 years who completed 2 food frequency questionnaires, 5 years apart, during the period 1995-2009. After 878,163 person-years of follow-up, 584 incident cases of CHD (101 fatal and 483 nonfatal), including 516 myocardial infarctions, were documented. There was a clear dose-response association between smoking and CHD risk among subjects with a low seafood/fish intake (

Despite the acknowledged importance of ascorbic acid (AA) in maintaining pregnancy and normal fetal development, its precise actions remain obscure. Therefore, we investigated the impact of maternal AA content on the growth of fetal mice during the gestation period using senescence marker protein-30/gluconolactonase (SMP30/GNL) knockout (KO) mice, which cannot synthesize AA in vivo.SMP30/GNL KO mice gave birth after a gestation period under conditions of absent, low, or normal AA intake. AA was measured using high-performance liquid chromatography and electrochemical detection. Whole-body sections were stained with hematoxylin and eosin, Elastica van Gieson, and Azan.The mothers in the group absent AA intake failed to bear young because of incomplete fetal development. Offspring born under the low-AA condition generally died within a few days after birth. Morphological analysis revealed that the latter neonates of SMP30/GNL KO mothers whose intake of AA was low during gestation manifested abnormal cardiac dilation, congestion of the liver and lungs, incompletely expanded pulmonary alveoli, and impaired vertebral bodies. In contrast, a normal AA diet produced healthy progeny.A diet sufficiently replete with AA is essential during the gestational period for normal tissue development in the fetus and neonate.

The ^{181}Ta quadrupole resonance [nuclear quadrupole resonance (NQR)] technique is utilized to investigate the microscopic magnetic properties of the Weyl semimetal TaP. We find three zero-field NQR signals associated with the transition between the quadrupole split levels for Ta with I=7/2 nuclear spin. A quadrupole coupling constant, ν_{Q}=19.250 MHz, and an asymmetric parameter of the electric field gradient, η=0.423, are extracted, in good agreement with band structure calculations. In order to examine the magnetic excitations, the temperature dependence of the spin-lattice relaxation rate (1/T_{1}T) is measured for the f_{2} line (±5/2↔±3/2 transition). We find that there exist two regimes with quite different relaxation processes. Above T^{*}≈30 K, a pronounced (1/T_{1}T)∝T^{2} behavior is found, which is attributed to the magnetic excitations at the Weyl nodes with temperature-dependent orbital hyperfine coupling. Below T^{*}, the relaxation is mainly governed by a Korringa process with 1/T_{1}T=const, accompanied by an additional T^{-1/2}-type dependence to fit our experimental data. We show that Ta NQR is a novel probe for the bulk Weyl fermions and their excitations.

Photoluminescence and excitation spectra have been investigated for undoped and nitrogen-doped TiO2 powders at low temperatures. A broad luminescence band peaking at 2.25 eV is observed in the undoped TiO2 powders. The 2.25 eV luminescence band exhibits a sharp rise from 3.34 eV in the excitation spectrum reflecting the fundamental absorption edge of anatase TiO2. On the other hand, the N-doped TiO2 powders obtained by annealing with urea at 350 and 500°C exhibit broad luminescence bands around 2.89 and 2.63 eV, respectively. The excitation spectra for these luminescence bands rise from the lower energy side of the fundamental absorption edge of anatase TiO2. The origin of the luminescence bands and N-related energy levels formed in the band-gap of TiO2 are discussed.

The Japanese prototype fast breeder reactor Monju restarted its system startup test in May 2010 after a 14-year interruption. In the first stage of the test, reactor physics parameters have been me...