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Forecasting the long-term fate of plutonium (Pu) is becoming increasingly important as more worldwide military and nuclear-power waste is being generated. Nagasaki sediments containing bomb-derived Pu that was deposited in 1945 provided a unique opportunity to explore the long-term geochemical behavior of Pu. Through a combination of selective extractions and molecular characterization via electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FTICRMS), we determined that 55 ± 3% of the bomb-derived 239,240Pu was preferentially associated with more persistent organic matter compounds in Nagasaki sediments, particularly those natural organic matter (NOM) stabilized by Fe oxides (NOMFe-oxide). Other organic matter compounds served as a secondary sink of these bomb-derived 239,240Pu (31 ± 2% on average), and

In this study, hetero-interface-structured Bi2Te3-nanoplate/Bi2Se3-electrodeposited films were prepared using all solution processes. Single-crystalline Bi2Te3 nanoplates were synthesized using a solvothermal method, and Bi2Te3 nanoplate films were prepared by drop-casting followed by thermal annealing. The electrodeposition time of the Bi2Se3 layer was tuned to obtain hetero-interface-structured films, wherein the gap between the Bi2Te3 nanoplates was filled. Cross-sectional scanning electron microscopy showed that the heterointerface structured films had a boundary between the composite layer and the Bi2Te3-nanoplate film. The X-ray diffraction patterns of the hetero-interface-structured films without thermal annealing exhibited peaks arising from Bi2Te3, as well as Bi2Se3 with and without antisite defects (SeBi), while those of the annealed film exhibited peaks from Bi2Te3, Bi2Se3, and the ternary alloys due to mutual diffusion. The annealed hetero-interface-structured film with an electrodeposition time of 40 min exhibited the highest power factor of 1.70 μW/(cm∙K2), which is 12-fold and 30% higher than that of the Bi2Te3-nanoplate and homo-interface-structured films (Bi2Te3-nanoplate/Bi2Te3-electrodeposited film), respectively. This enhancement was observed due to (a) increased electrical conductivity arising from the improved crystallinity of the Bi2Se3 electrodeposited layer and (b) increased Seebeck coefficient, resulting presumably from the combined effect of the heterostructured interface, decrease in the number of antisite defects, and formation of ternary alloys. Our findings provide a route for fabricating high-performance thermoelectric materials with low manufacturing costs.

This cross-sectional study examined the benefits of social dancing on postural stability and physical performance in dancers aged 50 years or more. Walking speed, lower limb reaction time and low back flexibility were measured in 202 social dancers and 202 community-dwelling comparison subjects aged 50-87 years. The results showed that dancers who were older than 60 years had better postural stability and faster leg reaction times, whilst dancers aged 50-59 showed only better flexibility, when compared with the controls. Male dancers had greater low back flexibility and leg reaction time compared to controls. In contrast, female dancers had superior performance only for leg reaction time when compared with controls. The results indicate that social dancing is associated with enhanced postural stability and physical performance in older adults.

In a sediment core of Nishiyama reservoir at Nagasaki city, depth profiles of (240)Pu/(239)Pu isotopic ratio, (239+240)Pu and (137)Cs activities were determined. Sediments containing plutonium and (137)Cs, which were deposited immediately after a detonation of Nagasaki atomic bomb, were identified in the core. Observed below the sediments were macroscopic charcoals, providing evidence for initial deposit of the fallout of the Nagasaki atomic bomb. This is the first entire depositional records of plutonium and (137)Cs released from the Nagasaki atomic bomb together with those from atmospheric nuclear tests.

Thimerosal is one of the best-known preservative agents for vaccines in the world but a relationship between its use and autism has long been suspected so that its effects on the brain need more detailed research. We here examined the influence of lipopolysaccharide injury to the blood-brain barrier on the penetration of mercury from thimerosal into mouse cerebrums, as well as the effect of chelator of heavy metals on cerebrum mercury content. Mercury can be expected to be detected in the cerebrum of normal mice, because the metal is present in standard mouse chow. When 60μg/kg of thimerosal was subcutaneously injected into the mouse, the mercury content in the cerebrum was significantly higher 48h after the thimerosal injection with a maximum peak after 72h. In addition, mercury content in the cerebrum was still higher on day 7 than in the control group. When lipopolysaccharide was pre-injected into mice to induce damage on blood-brain barrier, the mercury content in the cerebrum was significantly higher at 24 and 72h after the injection of 12μg/kg of thimerosal compared to the control group, this dose alone does not cause any increase. The mercury content in the cerebrums of mice was decreased to the control group level on day 7 when a chelator, dimercaprol, was administered once a day from days 3 to 6 after a 60μg/kg, s.c. injection. In addition, d-penicillamine as a chelator decreased the mercury contents in the cerebrum after the high dose administration. In conclusion, a physiological dose of thimerosal did not increase the content of mercury in the cerebrum, but levels were increased when damage to the blood-brain barrier occurred in mice injected with thimerosal. In addition, a chelator of heavy metals may be useful to remove mercury from the cerebrum.

High-resolution foraminiferal analysis was conducted on a short sediment core from the inner part of Osaka Bay, Japan. Changes in foraminiferal assemblages were associated with eutrophication, bottom water hypoxia, and changes in red tide-causing algae. Before the 1920s, the calcareous species Ammonia beccarii , and the agglutinated species Eggerella advena and Trochammina hadai were rare, but calcareous foraminifers in general were abundant. Between the 1920s and 1940s, calcareous foraminifers decreased abruptly in abundance, while A . beccarii , E . advena and T . hadai increased in abundance. This faunal change corresponded in time to an increase in nutrients flowing in through the Yodo River, and bottom water hypoxia related to eutrophication. In the 1960s and 1970s, A. beccarii , E . advena and T . hadai further increased in abundance to become dominant, and many calcareous foraminifers nearly disappeared, corresponding to increasing bottom water hypoxia related to the rapid increase in discharged nutrients during the high economic growth period from 1953 to 1971. After the 1990s, A. beccarii decreased rapidly in abundance and E . advena and Uvigerinella glabra increased in abundance. The main components of red tide-causing algae changed from dinoflagellates to diatoms in the 1980s through 1990s, thus there was a change in the food supply to the benthos, which may have caused the increase in abundance of E. advena and U. glabra .

The aim of this report is to investigate the effects of 8 weeks of intensive Tai Chi Chuan (TCC) training on physiological function and fear of falling (FOF) in the less-robust elderly. Forty-nine community-dwelling elderly, aged 60 or older, were classified randomly into a TCC training or control group. Physical performance measures (including one-leg stance, trunk flexion, and walking speed) and interviews were conducted before and after the intervention. The TCC group showed significant improvements in balance and flexibility, and a reduced FOF, when compared with the control group after the intervention. However, walking speed did not change significantly. The results suggest that a high-frequency, short-term TCC training program can improve balance, flexibility, and increase the confidence of less-robust elderly. These suggest the effectiveness of TCC for intervention as a means to prevent falling among high-risk elderly populations.

Coastal bays adjacent to metropolitan areas are commonly polluted heavily, and the direct and indirect results of pollution (e.g., heavy metal pollution, eutrophication, and hypoxia) seriously influence metazoan benthos. Historical metazoan trends, however, remain poorly documented and understood. Using the ostracode record of the past 150 years (210Pb and 137Cs age information), we show that anthropogenic impacts during industrialization seriously influenced the benthic metazoan ecosystem in a bay adjacent to a metropolis (Osaka Bay, Japan). Ostracode absolute abundance decreased by 90% from ca. A.D. 1910–1920 to ca. A.D. 1960–1970 as a result of Japan's rapid industrial development, coinciding with a rapid increase in concentration of various pollutants and the Osaka City population. The ostracode abundance has not recovered despite environmental legislation enforced after ca. A.D. 1960–1970.

The historical trends of polycyclic aromatic hydrocarbons (PAHs) in the sediment core of the moat in Osaka Castle, located at the center of Osaka city, Japan, were studied. The moats in Osaka Castle were built in the 1620s, and the undisturbed sediment core, which consists of atmospheric deposits in Osaka city from 1671 to 1976, was withdrawn from the moat. PAHs in the sediment core were identified and quantified in the total concentration range of 0.053–26 mg kg−1 dry wt. The highest content of PAHs was found in the sample, which was dated to 1944 during World War II. Osaka Castle was exposed to intense bombing raids during World War II, and the spiked peak of the PAH concentration during the mid-1940s was due to the air attacks. The total PAH concentration in the sediment core sample during World War II was about two-fold greater than the average after the war. This study made it appear that the largest impact of PAHs on the atmospheric environment in Osaka city in almost 300 years was caused by modern warfare.

ω-oxidation is regarded as the major pathway for the catabolism of leukotriene B4 (LTB4). To determine how LTB4 ω-hydroxylase is modulated in inflammatory bowel disease, we investigated the kinetic characteristics of this enzyme in 10 patients with Crohn's disease (CD), nine with ulcerative colitis (UC) and eight healthy control subjects. After incubating polymorphonuclear leukocytes with various concentrations of 3H-labeled LTB4, ω-oxidation products were serapated by high performance liquid chromatography (HPLC) and the radioactivity was measured by a liquid scintilation counter. The apparent Vmax values were significantly higher in both disease than in healthy control subjects, although the difference between CD and UC was insignificant. There was no difference in the apparent Km values. And the Vmax Km ratios of patients with CD were significantly higher than that of healthy control subjects. It is suggested that LTB4 metabolism is activated in inflammatory bowel disease (IBD) and that the modulation of this enzyme activity has an important role in the pathogenesis of inflammatory bowel disease.

The vertical distributions of fluorescent organic matter were investigated at three stations in the North Pacific. Fluorescence intensity was low in the upper layer, and increased rapidly to a maximum at ∼ 1000-m depth. This vertical profile is similar to that of phosphate and nitrate; in the water column above the fluorescence maximum, fluorescence varies linearly with phosphate, nitrate and silicate. This is the same trend that has been reported for fluorescence and nutrients in the coastal seas of Japan. It is suggested that fluorescent organic matter is degraded in the euphotic zone and regenerated in the water column by degradation of organic matter on the settling particles as in the case of the nutrients. When deeper water was irradiated with UV light, the intensity of fluorescence decreased rapidly with time, implying that photodegradation may be primarily responsible for degradation of the fluorescent substances in the upper layers.

A nonequilibrium chromatographic process has been analyzed mathematically using Mellin transforms. The peak characteristics, i.e. retention time, peak width, peak asymmetry and deviation from the Gaussian distribution are expressed in terms of the mean, variance, skewness and excess of the distribution function. The rates of the desorption and adsorption processes can be evaluated from the statistical quantities. The theory has also been applied to the adsorption on multiple sites.