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Background: Pediatric allergic rhinitis (AR), including cedar pollinosis (CP), is increasing in Japan. We investigated the effects of sublingual immunotherapy (SLIT), which has limited studies of its effectiveness in real‐world settings, on children with CP. Methods: This retrospective cohort study used a claim database in 2018–2021. Children aged ≤15 years with CP records in 2019 were eligible and were followed up through 2021. We included 2962 CP children undergoing SLIT and 547 who were not. The medication score was used to evaluate SLIT effectiveness in the cedar pollen dispersal season each year. Adverse events and the occurrence of allergic diseases were also evaluated. Results: Medication score was higher in the SLIT group during the index period but lower in 2021 compared to the non‐SLIT group (mean ± standard deviation: 5.17 ± 2.39 and 4.74 ± 2.38 in 2019, 3.13 ± 2.30 and 3.55 ± 2.48 in 2021, respectively). The adjusted mean difference between groups from 2019 to 2021 was −0.62 (95% confidence interval: −0.86 to −0.39, p <.0001), and the medication score was reduced in the SLIT group (risk ratio: 1.2: 1.1 to 1.3). The occurrence of adverse events involving abdominal disorders (adjusted odds ratio [aOR]: 0.64: 0.51 to 0.81), asthma exacerbation (aOR: 0.37: 0.24 to 0.57), and allergic diseases involving hay fever unrelated to CP (aOR: 0.60: 0.45 to 0.80) or asthma (aOR: 0.71: 0.58 to 0.86) was lower in the SLIT group. Conclusion: In children with CP, SLIT is effective, well tolerated, and could decrease the occurrence of other allergic diseases. [ABSTRACT FROM AUTHOR]

Background: One‐third of the people in Japan are colonized with Staphylococcus aureus (S. aureus) and suffer from virulence factor‐mediated subclinical inflammation of the nares. We investigated whether subclinical inflammation contributed to cedar pollinosis affecting 20 million people annually. Methods: The study participants were 814 inhabitants of the A or B prefectures. We compared the colonization rate and population structure of S. aureus, in association with the prevalence of cedar pollinosis, between participants in these two areas. Results: A prefecture had twice the annual amount of airborne cedar pollen compared with B. The prevalence of cedar pollinosis was significantly higher in A (23.5%) than in B (13.1%) (p = 0.0004). Moreover, the prevalence of cedar pollinosis was higher in female participants (23.3%) than in male participants (14.7%) (p = 0.003). In addition, the prevalence of cedar pollinosis was higher in S. aureus carriers (24.2%) than in S. aureus noncarriers (17.9%) (p = 0.03). The isolation rate of clonal complex (CC) 508 was higher in the A group (21%) than in the B group (7%) (p = 0.015). Conclusion: Nasal colonization of S. aureus is a major risk factor for cedar pollinosis. However, the direct mechanism of this risk is currently unknown. The prevalence of cedar pollinosis in the research area was proportional to the amount of cedar pollen. The prevalence of cedar pollinosis was higher in S. aureus carriers (24.2%) than in S. aureus noncarriers (17.9%) (p = 0.03). The prevalence of cedar pollinosis was higher in female participants (23.3%) than in male participants (14.7%) (p = 0.003). [ABSTRACT FROM AUTHOR]

Summary This article presents a large eddy simulation and experimental study of cedar façade behavior exposed to a 900 kW window spilled flame. The experiments used for validation were carried out in the Building Research of Institute of Japan in Tsukuba according to JIS A 1310 method. The compartment fire was modeled by using the modified eddy dissipation model with a diffusion mixing time scale for the near wall laminar region of combustion model, oneEqEddy model of turbulence model, pyrolysis chemistry mode of pyrolysis model, and finite volume discrete ordinates method of radiation model. The fire flame is treated as optically thin, and a fixed radiant fraction 0.35 is used to calculate the radiation source term. The pyrolysis model of cedar was modeled and optimized according to the results of fire propagation apparatus test. The influence of cedar parameters on time‐to‐pHRR (peak HRR), pHRR, and (total heat release rate) THR curves of facade fire were clarified by a series of simulation varying from thermal density, conductivity, heat capacity, and pyrolysis reaction parameters. It indicates the simulation results show a reasonable good quantitative agreement with experimental measurements. The activation energy of cedar pyrolysis shows a great influence on the time‐to‐pHRR, low pHRR, and THR of cedar facade. [ABSTRACT FROM AUTHOR]

Background Patients allergic to pollen have been known to become more symptomatic during pollen season compared with the nonpollen season. However, there are few studies regarding whether higher exposure to pollen might increase the prevalence of allergic diseases. Methods An ecological analysis was conducted to evaluate whether pollen exposure is associated with the prevalence of allergic diseases in schoolchildren. Pollen count data of Japanese cedar ( Cryptomeria japonica) and Japanese cypress ( Chamaecyparis obtusa), which are the major pollen allergens in Japan, were obtained from each prefecture. The prevalence of allergic diseases in schoolchildren in each prefecture was based on a nationwide cross-sectional survey using the International Study of Asthma and Allergies in Childhood questionnaire. Results After omitting three prefectures where pollen data were not available, data of 44 prefectures were analysed. The prevalence of allergic rhinoconjunctivitis in children aged 6-7 years was positively associated with both cedar and cypress pollen counts ( P = 0.01, both), whereas the prevalence of allergic rhinoconjunctivitis in children aged 13-14 years was positively associated with only cypress pollen counts ( P = 0.003). Furthermore, the prevalence of asthma was positively associated with cedar pollen counts in 6- to 7-year-old children ( P = 0.003) but not cypress pollen counts in either age group. Conclusions There are ecological associations between pollen counts and the prevalence of allergic diseases in Japanese schoolchildren. Further studies are needed to determine whether the difference between the effects of cedar and cypress pollens is attributable to pollen counts or allergenicity. [ABSTRACT FROM AUTHOR]

The article discusses the factors that control the acid-neutralizing capacity (ANC) of cedar forest watersheds in different ages and topographic characteristics. This study was conducted in Japan's cedar forests. It shows the significance of the index for streamwater acidification brought on by external and internal factors such as chronic acid deposition and soil acidification due to nitrification. The influence of forest clear-cutting and regrowth in internal acidification was studied further indicating stream pH.

Soil carbon cycling was studied in Japanese cedar plantations with different stand ages after clear-cutting and was analyzed by a compartment model. The amount of biomass and the litterfall rate increased rapidly with the growth of Japanese cedar, which were approximated by a simple logistic function of stand age. The accumulation of A0 layer decreased from 21 t ha−1 to 5 t ha−1 during the 10 years following clear-cutting, and then recovered to nearly the same level as before clear-cutting within 20 years after clear-cutting, although the amount of soil carbon in the mineral soil recovered more than 40 years after clear-cutting. The total and mineral soil respiration rates increased rapidly after clear-cutting and gradually decreased in young stands and stabilized in old stands. The relative decomposition rate of the A0 layer and organic matters in mineral soil was high in the young stands because of the relatively high soil temperature rather than the soil moisture content. After the closing up of the canopy, the relative decomposition rates of the A0 layer and humus in the mineral soil stabilized at 0.14 to 0.16 y–1 and 0.005 to 0.013 y−1, respectively. Consequently, soil carbon cycling was strongly affected by clear-cutting. The amount of soil carbon rapidly decreased because of the cessation of litterfall and the increase of the relative decomposition rate of the A0 layer and humus, and recovered gradually to the level before clear-cutting with the growth of the cedar plantation. The change in soil carbon cycling with stand development was partly caused by the change in soil temperature and moisture content but was mainly caused by the amount of cedar litterfall which changed significantly in the early stage of the stand following clear-cutting, and became slower and leveled off in the late stage with stabilization of the environmental conditions and litterfall rate. [ABSTRACT FROM AUTHOR]

Abstract This study examined the effects of snowfall on the beginning day of Cryptomeria japonica pollen release and predicted it under global climate change. We used a statistical method in order to investigate when the pollen release would start and how much sooner it would be, by using data on predicted meteorological conditions under global warming in Yamagata City, Japan. Estimation accuracy was improved by multiple regression by using the mean air temperature from January to February and snowfall depth in February. Adding snowfall depth yielded more accurate estimates of the beginning day of pollen release than using air temperature alone. It is possible that the effects of heat insulation and cooling by snow delay the flowering day. Under the predicted global climate change, we expect the beginning day of pollen release to become earlier in Yamagata City. The date would be 8 February in approximately 100 years, compared with 20 February at the earliest now. Eighty years from now the date could be earlier than any date recorded so far. [ABSTRACT FROM AUTHOR]