Differences in Leaf Morphology between Native and Exotic Dandelion Species in the Chikuma River Basin, Japan

Article環境科学年報35:26-31(2013)research repor

A Simple Method to Record the Plant Pith Cavity for Field Surveysフィールドにおける植物の髄腔の簡易記録法について

フィールドにおける植物の髄腔を簡便に記録する方法として「朱肉スタンプ法」を提案するとともに，トクサ（Equisetum hyemale）を例にして精度と改善点を検討した。この方法は，茎断面を朱肉につけて紙に印影を記録するものである。茎の外径の異なるトクサ個体を採取し，それぞれ連続した節間の断面について本法を回ずつ試行した。印影をスキャナで画像データに変換し，外径，髄腔径を計測し，皮層厚と髄腔率を算出した。その結果，計測値の誤差はほとんど以下であった。髄腔率は個体とも～ で，節位との関係も類似していた。また，スタンプ成功率は皮層厚との間に有意な曲線関係が認められ，皮層が厚いまたは薄い場合には成功率が低下した。断面の作成とスタンプの仕方に訓練が必要であるが，朱肉スタンプ法は植物の髄腔計測に充分適用できると考えられた。Article環境科学年報33:68-71(2011)research repor

Preterm toddlers have low nighttime sleep quality and high daytime activity.

A number of studies have been made on the sleep characteristics of children born preterm in an attempt to develop methods to address the sleep problems commonly observed among such children. However, the reported sleep characteristics from these studies vary depending on the observation methods used, i.e., actigraphy, polysomnography and questionnaire. In the current study, to obtain reliable data on the sleep characteristics of preterm-born children, we investigated the difference in sleep properties between 97 preterm and 97 term toddlers of approximately 1.5 years of age using actigraphy. Actigraphy units were attached to the toddlers’ waists with an adjustable elastic belt for 7 consecutive days, and a child sleep diary was completed by their parents. In the study, we found that preterm toddlers had more nocturnal awakenings and more daytime activity, suggesting that preterm-born children may have a different process of sleep development in their early development

Evaluation of the genotoxicity of PM2.5 collected by a high-volume air sampler with impactor

Abstract Background The harmful effects of fine particles with an aerodynamic diameter less than 2.5 μm (PM2.5) on respiratory organs are emphasized in pollution studies because PM2.5 have high deposition rates in the respiratory organs and contain various hazardous compounds. In this study, a sampling method combining a high-volume air sampler (HV) with a PM2.5 impactor was developed for collecting large quantities of PM2.5. The concentrations of elemental carbon (EC), organic carbon (OC), inorganic ions, and polycyclic aromatic hydrocarbons (PAHs) were measured in PM2.5 collected by the high-and low-volume air samplers (LV). Results Similar results were obtained from the HV and LV methods, with respect to inorganic carbon, organic carbon, sodium ions, ammonium ions, and PAHs with more than four rings. Because of the much larger amount of PM2.5 could be collected by the HV method, the trace constituents, that were difficult to detect by the conventional LV method, were readily detected by the HV method. Furthermore, when the microsuspension method that was modified more sensitive Ames mutagenicity test, was used to test the PM2.5 samples at four sites, mutagenic activities were detected by strains TA100 and TA98. Most of the mutagenic activity was associated with the PM2.5 fraction and mutagenic activity in winter was greater than that in summer. Conclusions The HV method produced results similar to those from the conventional LV method with respect to the PM2.5 components present in the atmosphere in relatively high concentrations, but its 40-fold greater flow rate enabled the detection of mutagenic compounds present in only trace concentrations

Preterm toddlers have low nighttime sleep quality and high daytime activity

A number of studies have been made on the sleep characteristics of children born preterm in an attempt to develop methods to address the sleep problems commonly observed among such children. However, the reported sleep characteristics from these studies vary depending on the observation methods used, i.e., actigraphy, polysomnography and questionnaire. In the current study, to obtain reliable data on the sleep characteristics of preterm-born children, we investigated the difference in sleep properties between 97 preterm and 97 term toddlers of approximately 1.5 years of age using actigraphy. Actigraphy units were attached to the toddlers' waists with an adjustable elastic belt for 7 consecutive days, and a child sleep diary was completed by their parents. In the study, we found that preterm toddlers had more nocturnal awakenings and more daytime activity, suggesting that preterm-born children may have a different process of sleep development in their early development