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This study examined the accumulation and tissue distribution of radioactive cesium nuclides in Japanese Black beef heifers raised on roughage contaminated with radioactive fallout due to the accident at the Fukushima Daiichi Nuclear Power Station on March 2011. Radiocesium feeding increased both (134)Cs and (137)Cs levels in all tissues tested. The kidney had the highest level and subcutaneous adipose had the lowest of radioactive cesium in the tissues. Different radioactive cesium levels were not found among parts of the muscles. These results indicate that radiocesium accumulated highly in the kidney and homogenously in the skeletal muscles in the heifers.

Some plants are able to tolerate salinity using salt glands on the leaf surface, which secrete excess salts transported into the leaves. Rhodes grass (Chloris gayana Kunth) reportedly possesses such salt glands, but the features of secretion remain unclear. In the present study, we compared the ability of Rhodes grass salt glands to secrete sodium and potassium with the aim of clarifying the preference of cations for secretion. In both whole plant experiments and detached leaf experiments, NaCl treatment increased Na+ secretion and KCl treatment increased K+ secretion. When the ratios of the amount of secreted ions to their concentration in the leaves were compared between Na+ and K+, the ratio was greater with Na+ than K+. The addition of NaCl to the KCl solution significantly decreased K+ secretion, but the addition of KCl to the NaCl solution did not have a significant effect on Na+ secretion. These results indicate that the salt glands of Rhodes grass can secrete both Na+ and K+, but the abil...

We conducted two feeding experiments to evaluate the effects of cellooligosaccharide (CE) supplementation on growth performance in grazing beef calves. Calf sex and age and duration of the experimental period differed between the experiments. Experiment 1 (10 weeks) used 5.6-month-old castrated males; Experiment 2 (13 weeks) used 3.9-month-old females. Eight Japanese Black calves were assigned to either a control group (CON) or an experimental group (CE) fed CE at a rate of 10 g/day mixed with concentrate. Calves were stocked in fields in which Kentucky bluegrass was dominant. In both experiments, average daily gain tended to be greater in CE than in CON, especially in late stages of experiments, but no significant differences in body weight changes were observed. In Experiment 2, final heart girth was larger in CE than in CON calves. We monitored rumen microbial community composition in Experiment 2 and found increases in fibrolytic bacteria and methanogenic archaea in CE calves, but the overall microbial composition did not differ between the groups. Our results suggest that supplementation with CE may positively affect growth performance in weaned calves on pasture, but longer-term CE supplementation may be required to exhibit the effect.

上向流型生物ろ床装置を用い, チオ硫酸塩を添加した硫黄脱窒による養液栽培排水の連続処理実験を行った.処理装置のスタートアップに要する期間は1週間程度と短く, 窒素負荷5.3kg/m3.dayの運転を2カ月半継続できた.流入負荷が0.16-0.46kgN/m3.dayの間で変動しても, 処理水質は安定していたが, 水温が15℃以下に低下すると処理水質が悪化する傾向にあった.処理槽内ではチオ硫酸塩を用いた脱窒がほぼ量論的に進行した.槽内には硫黄粒が約7%蓄積され, これはきわめて利用されやすい形態のものであった.槽内に増殖した生物膜を取り出して, 種々の条件で回分実験を行うことにより, 硫黄脱窒活性, 硫黄還元活性, 他栄養性脱窒活性を求めた.生物膜のチオ硫酸脱窒活性は極めて高く, 槽内に蓄積された硫黄粒を用いた脱窒活性も高かった.一方, 高負荷条件では他栄養性脱窒も進行し, その活性はチオ硫酸塩脱窒活性の約1/5であった.硫黄還元活性もまた酸化活性の1/5程度であったことから, 槽内に硫黄粒の酸化と還元のサイクルが形成されていると推定された.以上のことより, 多様な生態系による硫黄粒の繰り返し利用により, 負荷変動に強く, 汚泥発生量の少ない処理が可能であると考えられた.

2槽型上向流生物ろ床装置を用いて硫酸塩還元と硫黄脱窒を組み合わせた処理法の可能性について検討した.人工廃水を供給した第1槽で硫酸塩還元を優先して起こすことができた.第1槽流出水とともに硝化液循環を想定して硝酸を供給した第2槽では, 他栄養性脱窒と硫黄脱窒が同時に進行した.第2槽において硫酸塩還元活性が認められた.両槽に生育した硫酸塩還元細菌はプロピオン酸もしくは類似の有機物からの酢酸の生成に量論的に関与していた.第2槽中の硫黄脱窒細菌は硫酸塩還元によって第1槽から供給された硫化物を利用して量論的に脱窒を行った.第2槽中の他栄養性脱窒細菌は第1槽から供給された酢酸を利用して量論的に脱窒を行った.本処理槽の汚泥発生量は少なく, 運転期間を通じて汚泥の引き抜きの必要はなかった.装置内の微生物の反応について, 熱力学的に考察を行い, 処理槽内で微生物の住み分けが起こっていることを推定した.

In this study, the applicability of CIP-FEM to numerical simulation of two-dimensional unsteady incompressible viscous fluid flow is discussed. In this procedure, the basic differential equations of the flow are separated into advection and non-advection phases. Analysis of the advection phase is based on an approximate solution given by a cubic polynomial interpolation and the one of the non-advection phase is performed by FEM. The formulation in order to solve the basic equation of viscous fluid by using this procedure is discussed and also described. Numerical simulation of the problem of viscus flow is carried out. The applicability and effectiveness of the proposed method is discussed with the obtained numerical results.

In this paper, a novel and effective numerical solution procedure for solving convection-dominated flows is proposed in the context of the finite element method (FEM). The procedure, which we call CIP-FEM, is a combination of the cubic interpolated propagation (CIP) method in the advection phase with FEM in the diffusion phase. Applicability of the method is shown in the comparison of other existing solutions for the rotating cone problem known as a bench mark test in a two-dimensional convective diffusion equation.