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A large quantity of radionuclides was released by the Fukushima Daiichi Nuclear Power Plant accident in March 2011, and those deposited on ground and vegetation could return to the atmosphere through resuspension processes. Although the resuspension has been proposed to occur with wind blow, biomass burning, ecosystem activities, etc., the dominant process in contaminated areas of Fukushima is not fully understood. We have examined the resuspension process of radiocesium ( 134,137 Cs) based on long-term measurements of the atmospheric concentration of radiocesium activity (the radiocesium concentration) at four sites in the contaminated areas of Fukushima as well as the aerosol characteristic observations by scanning electron microscopy (SEM) and the measurement of the biomass burning tracer, levoglucosan. The radiocesium concentrations at all sites showed a similar seasonal variation: low from winter to early spring and high from late spring to early autumn. In late spring, they showed positive peaks that coincided with the wind speed peaks. However, in summer and autumn, they were correlated positively with atmospheric temperature but negatively with wind speed. These results differed from previous studies based on data at urban sites. The difference of radiocesium concentrations at two sites, which are located within a 1 km range but have different degrees of surface contamination, was large from winter to late spring and small in summer and autumn, indicating that resuspension occurs locally and/or that atmospheric radiocesium was not well mixed in winter/spring, and it was opposite in summer/autumn. These results suggest that the resuspension processes and the host particles of the radiocesium resuspension changed seasonally. The SEM analyses showed that the dominant coarse particles in summer and autumn were organic ones, such as pollen, spores, and microorganisms. Biological activities in forest ecosystems can contribute considerably to the radiocesium resuspension in these seasons. During winter and spring, soil, mineral, and vegetation debris were predominant coarse particles in the atmosphere, and the radiocesium resuspension in these seasons can be attributed to the wind blow of these particles. Any proofs that biomass (Continued on next page)

Azoospermia affects up to 1% of adult men. Non-obstructive azoospermia is a multifactorial disorder whose molecular basis remains largely unknown. To date, mutations in several genes and multiple submicroscopic copy-number variations (CNVs) have been identified in patients with non-obstructive azoospermia. The aim of this study was to clarify the contribution of nucleotide substitutions in known causative genes and submicroscopic CNVs in the genome to the development of non-obstructive azoospermia. To this end, we conducted sequence analysis of 25 known disease-associated genes using next-generation sequencing and genome-wide copy-number analysis using array-based comparative genomic hybridization. We studied 40 Japanese patients with idiopathic non-obstructive azoospermia. Functional significance of molecular alterations was assessed by in silico analyses. As a result, we identified four putative pathogenic mutations, four rare polymorphisms possibly associated with disease risk, and four probable neutral variants in 10 patients. These sequence alterations included a heterozygous splice site mutation in SOHLH1 and a hemizygous missense substitution in TEX11, which have been reported as causes of non-obstructive azoospermia. Copy-number analysis detected five X chromosomal or autosomal CNVs of unknown clinical significance, in addition to one known pathogenic Y chromosomal microduplication. Five patients carried multiple molecular alterations. The results indicate that monogenic and oligogenic mutations, including those in SOHLH1 and TEX11, account for more than 10% of cases of idiopathic non-obstructive azoospermia. Furthermore, this study suggests possible contributions of substitutions in various genes as well as submicroscopic CNVs on the X chromosome and autosomes to non-obstructive azoospermia, which require further validation.

YVnormalO4:normalBi3+,normalEu3+ nanoparticles were prepared by the wet chemical synthesis in various concentrations of sodium citrate, 15⩽xcit⩽90 , where xcit is the nominal molar percentage of citrate relative to the sum of metallic ions, Y3+ , Bi3+ , and Eu3+ . Mean primary nanoparticle diameter and mean hydrodynamic size in the aqueous colloidal solution have minimum values, 21 and 36nm , respectively, for the sample prepared at xcit=50 . The transparency of the aqueous colloidal solution in the visible region increases with decreasing the mean hydrodynamic size, and the sample prepared at xcit=50 shows the highest transparency. YVnormalO4:normalBi3+,normalEu3+ nanoparticles show the characteristic photobleaching behavior and the photoreduction of V5+ to V4+ under the irradiation of near-UV light, where the fraction of photobleach becomes larger at large xcit . These results suggest that the citrate ion works not only as an effective dispersion agent, but also as a reducing agent against V5+ of YVnormalO4:normalBi3+,normalEu3+ .

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