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Understanding the regeneration and succession of belowground communities, particularly in forests, is vital for maintaining ecosystem health. Despite its importance, there is limited knowledge regarding how fungal communities change over time during ecosystem development, especially under different forest restoration strategies. In this study, we focused on two restoration methods used in northern Japan: monoculture planting and natural regeneration. We examined the responses of the fungal community to monoculture plantations (active tree planting) and naturally regenerated (passive regeneration) forests over a 50-year chronosequence, using natural forests as a reference. Based on DNA metabarcoding, we assessed the richness of fungal Operational Taxonomic Units (OTUs) and their dissimilarity. Our findings revealed that soil fungal richness remained stable after natural regeneration but declined in monoculture plantations, from 354 to 247 OTUs. While the compositional dissimilarity of fungal assemblages between monoculture plantations and natural forests remained consistent regardless of the time since tree planting, it significantly decreased after natural regeneration, suggesting recovery to a state close to the reference level. Notably, the composition of key functional fungal groups—saprotrophic and ectomycorrhizal— has increasingly mirrored that of natural forests over time following passive natural regeneration. In summary, our study suggests that monoculture plantations may not be effective for long-term ecosystem function and service recovery because of their limited support for soil fungal diversity. These results underscore the importance of natural regeneration in forest restoration and management strategies. [ABSTRACT FROM AUTHOR]

SUMMARY In Tohoku Region Pacific Coast Earthquake, many of the power equipment (especially center clamping type bushings for power transformers) were damaged due to the seismic motion that exceeds the design criteria. The problem of the conventional seismic analysis became clear as the actual damage was revealed. Since elaboration of seismic analysis and evaluation technology was called for, the elaboration possibility of seismic analysis was verified by carrying out comparison with various test results and the analysis result by the latest technique. [ABSTRACT FROM AUTHOR]

To quantify the contribution of soil moisture to seasonal and annual variations in soil CO efflux in a cool-humid deciduous broadleaf forest, we measured soil CO efflux during the snow-free seasons of 2005-2008 using an automated chamber technique. This worked much better than manual chambers employing the same steady-state through-flow method. Soil CO efflux (g C mperiod) during the snow-free season ranged from 979.8 ± 49.0 in 2005 to 1131.2 ± 56.6 in 2008 with a coefficient variation of 6.4 % among the 4 years. We established two-parameter (soil temperature and moisture) empirical models, finding that while soil temperature and moisture explained 69-86 % and 10-13 % of the temporal variability, respectively. Soil moisture had the effect of modifying the temporal variability of soil CO efflux, particularly during summer and early fall after episodic rainfall events; greater soil moisture enhanced soil CO efflux in the surface soil layers. High soil moisture conditions did not suppress soil CO efflux, leading to a positive correlation between normalized soil CO efflux (ratio of the measured to predicted efflux using a temperature-dependent Q function) and soil moisture. Therefore, enhanced daily soil CO efflux following heavy rainfall events could significantly reduce net ecosystem exchange (i.e. daily net ecosystem production) by 32 % on some days. Our results highlight the importance of precisely estimating the response of soil CO efflux to changes in soil moisture following rainfall events when modeling seasonal carbon dynamics in response to climate change, even in humid monsoon regions. [ABSTRACT FROM AUTHOR]

The article presents a study on the isolation and characterization of leptospires from raccoons in Japan. This study investigated whether raccoons in Japan carried leptospires in their kidneys. Seventy-one raccoons were captured in Kanagawa Prefecture and 53 raccoons were captured at a zoological park in Nagasaki Prefecture, both in Japan, and leptospira was isolated from 2 of the 71 raccoons and 33 of the 53 raccoons. Anti-leptospira antibodies were found in 16 of 124 raccoons (12.9 %) in Kanagawa and 33 of 53 (62.3 %) raccoons in Nagasaki. Although the claim that raccoons carried leptopires in their kidney at the time imported, it is still believed that imported animals are reservoir animals of leptospires in Japan.

Arctic ecosystems are altered profoundly by climate changes. However, the responses of Arctic marine and terrestrial ecosystems as well as their biodiversity to global warming remain largely unknown. This article provides comprehensive insights into the results and major findings from the Arctic Challenge for Sustainability (ArCS) Project – an Arctic region research program initiated in Japan, which aims to address and advance our understanding of these uncertainties. Marine ecosystem studies have identified several biogeochemical processes that are associated with sea ice decline and northward transport and shift of marine species across multiple trophic levels over the Bering and Chukchi Sea shelves. Studies of the terrestrial ecosystem have identified factors that are important for the understanding of terrestrial biodiversity and ecosystems, including Arctic lakes, under the presence of global warming. Novel fungal species from the Arctic terrestrial ecosystem have also been isolated and described. Overall, these results could contribute to the conservation and sustainable management of the Arctic ecosystem services. • Most publications from the ArCS project were reviewed. • Biogeochemical process assciated with sea ice decline and northward shift of marine species were revealed. • Novel fungal species in the terrestrial ecosystem and notable contributions of biological interaction to ecosystem changes were discovered. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the seasonal and annual variations in soil respiration in a cool-temperate oak–birch forest in central Japan and, in particular, to reveal factors determining seasonal variations in the temperature dependence of respiration based on soil CO2 efflux data for 1999–2002. The daily soil carbon efflux was moderate in late spring (1.8–2.9gCm−2 day−1 in May), increased sharply to a peak in summer (4.6–6.0gCm−2 day−1 in August), and decreased in autumn (1.5–2.5gCm−2 day−1 in November). In winter, the carbon efflux from the snow surface was low (0.29–0.71gCm−2 day−1). Soil temperature exerted principle control on the seasonal and annual variation of soil respiration. Furthermore, reduced soil water content decreased soil respiration in summer when droughts occurred. The temperature function driven on a seasonal scale showed large variations in seasonal Q 10 and R 0 (simulated soil respiration at a soil temperature of 0°C), e.g. a higher Q 10 and lower R 0 in spring and a lower Q 10 and higher R 0 in autumn. These large variations in seasonal Q 10 and R 0 might reflect confounding effects of temperature sensitivity and seasonal changes in physiological activities induced by root phenology, microbial biomass, and other factors. These results suggest that if the objective is to simulate soil respiration in a particular season, a seasonal Q 10 function derived from the target period must be used, especially in a forest ecosystem possessing distinct seasonal changes. Conversely, the annual Q 10 function derived from all measurements of daily soil temperature at −1cm across the 4 years (Q 10 =3.8) was adequate for estimating total annual soil respiration because it may integrate all processes that influence soil carbon efflux, despite the fact it may under- or overestimate daily soil carbon efflux on a seasonal scale. Based on this single annual Q 10 function, the annual mean soil respiration in 1999–2002 was estimated to be 853.5±42.4gCm−2 without topography correction, and 725.5±36.0gCm−2 with topography correction for a 1ha experimental area. The estimated annual soil respiration (1999–2002) gave coefficient of variation (CV) value of less than 10%, suggesting a small inter-annual variability in annual soil respiration during 1999–2002 in this forest, since the annual mean temperature was similar in the 4 years of the survey. Carbon efflux from the snow surface accounted for 10% of the annual soil respiration, with a value of 84.3±7.0gCm−2, indicating the importance of quantifying winter CO2 efflux within a forest ecosystem in a cold and snowy region. [Copyright &y& Elsevier]

At the Yokohama General Hospital, pharmacist-led antimicrobial stewardship programs (ASP) including antifungal stewardship programs (AFP) were started in 2012. To investigate the efficacy of the programs, we compared several parameters that are recommended for the measurement of ASP in Japan based on pre- and post-AFP activities. The subjects were inpatients who developed candidemia between April 2008 and March 2016. They were divided into two groups: pre-AFP (April 2008 until March 2012) and post-AFP (April 2012 until March 2016). The results were compared between the two groups. The cumulative optimal antifungal drug usage rate, as a process parameter, significantly increased in the post-AFP group (p = 0.025). Furthermore, the days of therapy of antifungal drugs in the pre- and post-AFP groups was median 6.0 (interquartile range [IQR] 0.3–15.7) and median 3.4 (IQR 1.9–3.4) per 1,000 patient-days, respectively; there was a significant decrease in the post-AFP group (p < 0.001). Expenditure on antifungal drugs, as an outcome parameter, in the pre- and post-AFP groups was 9390.5 ± 5687.1 and 5930.8 ± 4687.0 US dollars, respectively; there was a significant decrease in the post-AFP group (p = 0.002). These results suggest that pharmacist-led antifungal stewardship activities improve both outcome and process parameters. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to determine the effects of age, period, and birth cohort on cervical cancer mortality rate trends in Japanese women, by age-period-cohort (APC) analysis. Additionally, we analyzed projected mortality rates., Methods: We obtained data on the number of cervical cancer deaths in Japanese women from 1975-2011 from the national vital statistics and census population data. A cohort table of mortality rate data was analyzed on the basis of a Bayesian APC model. We also projected the mortality rates for the 2012-2031 period., Results: The period effect was relatively limited, compared with the age and cohort effects. The age effect increased suddenly from 25-29 to 45-49 years of age and gently increased thereafter. An analysis of the cohort effect on mortality rate trends revealed a steep decreasing slope for birth cohorts born from 1908-1940 and a subsequent sudden increase after 1945. The mortality rate projections indicated increasing trends from 40 to 74 years of age until the year 2031., Conclusions: The age effect increased from 25-29 years of age. This could be attributable to the high human papilloma virus (HPV) infection risk and the low cervical cancer screening rate. The cohort effect changed from decreasing to increasing after the early 1940s. This might be attributable to the spread of cervical cancer screening and treatment before 1940 and the high HPV infection risk and reduced cervical cancer screening rate after 1945. The projected mortality rate indicated an increasing trend until the year 2031.