1,610 research outputs found
Nitrate Contamination of Groundwater and Soil Management
No full textThe Japanese Government set the environmental quality standard for nitrate (NO3) in groundwater at 10 mg N L1 in 1998, based on a level considered acceptable for avoiding infant methemoglobinemia. In 1998, 6.3% of groundwater in Japan contained NO3 exceeding 10 mg L¡¦, with agriculture regarded to be a primary source of the NO3 (Environmental Agency, Japan, 1999). This paper aims to define the mechanisms of NO3 contamination of groundwater associated with soil management in arable land.
The author gives an overview of the relation between nitrogen (N) fertilization and groundwater contamination. First of all, the utilization efficiency of N fertilizers for outdoor cultivation of vegetables is usually 50% or less (Nishio, 2001; Vance, 2001). Although N fertilizer is essential for crop production, excessive N could leach out of arable soils and eventually cause NO3 contamination of groundwater. However, conversely, excessive N is necessary as insurance in some cases, such as when there is heavy rainfall immediately after fertilization. It should be also noted that some vegetables physiologically require a high content of N in soil even at harvest.
Nitrate leaching from different fertilizers was monitored for 7 years and the data were evaluated using an N and water balance equation (Maeda et al., 2003). Excessive N from chemical fertilizers caused substantial NO3 leaching, while compost application was promising to achieve high yields and low N leaching during a few years but led to the same level of NO3 leaching as that in the plots subjected to chemical fertilizer application over longer periods of time. Thus, it is of importance to predict the N mineralization rates both for manure and for soil under natural conditions. Experimental results of this kind can provide full information on N dynamics in fields for policy decisions or regulations to reduce NO3 leaching while maintaining crop yields. Likewise, we must consider other influencing factors such as soil types, climatic conditions, and cropping systems for this purpose
Acetoin Metabolism of Bacteria
No full textPart I On the Production of Acetoin Using E. coli, A. aerogenes, Sal. typhi and Staph. aureus as test organisms, the auther studied on the production of acetoin by the growing cells and the resting cells of these microorganisms and the following results were obtained. 1) While E. coli did not synthesize acetoin on its growth, A. aerogenes showed marked production of acetoin on growth on the media containing glucose, lactate or pyruvate as C-source. In the case of Sal. typhi and Staph. aureus, a small production of that was observed. 2) An accumulation of pyruvate into culture media was rapidly decreased from about the resting phase in the culture of A. aerogenes that was capable of synthesize action. On the other hand, the accumulation of pyruvate was decreased its amount fairly gradually by E. coli that had no capacity of acetoin sythesis. 3) The resting cells of either species could produce acetoin to some degree at the expense of glucose, lactate, pyruvate and succinate. The optimum pH of this reaction was found to be at about 6.0. 4) From the study on the effect of pH on oxidation of pyruvate by the resting cells of E. coli and A. aerogenes, it could be postulated that the mechanism yielding acetoin from pyruvate in low pH could work more sufficiently at A. aerogenes, than at E. coli. 5) The production of acetoin was accelerated very highly by the simultaneous addition of glucose and pyruvate into the media, and also was accelerated by the addition of VB(1), Mg(++) or ATP. Part 2 On the Degradation of Acetoin Using the 4 strains of bacteria as in the preceding paper, part I, the author studied on the degradation of acetoin by the growing cells and the resting cells of these microorganisms. The following results were obtained. 1) All the microorganisms tested except Staph. aureus could grow by utilizing acetoin as C-source on the media containing the minimal nutritional requirement, namely N-source and vitamins. But Staph. aureus did not show the growth for a lack of capacity utilizing acetoin. 2) As peptone and acetoin was added simultaneously into the media, all the species of bacteria could degrade acetoin and yielded a large amount of pyruvate and a little amount of lactate as the metabolite. 3) Generally the resting cells of all species showed a fairly large O(2)-uptake at the expense gf acotoin as substrate. However, the O(2)-uptake was somewhat small in the reaction by Staph. aureus compared with by the other bacteria. 4) As for the oxidation products of acetoin by the resting cells of the microorganisms pyruvate was found to be a predominant metabolite. Acetoin had possibly been undergone oxidative decarboxylation in the first place and resulted in pyruvate
Sedimentary environments of the lower part of the Himenoura Group, Amakusa-Kamishima, Kumamoto Prefecture, southwest Japan
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Smartphone viewing distance and sleep: an experimental study utilizing motion capture technology
No full textMichitaka Yoshimura,1,* Momoko Kitazawa,1–3,* Yasuhiro Maeda,2 Masaru Mimura,4 Kazuo Tsubota,1 Taishiro Kishimoto,4,5 1Department of Ophthalmology, Keio University School of Medicine, Tokyo, 2RIKEN Center for Advanced Photonics, Wako, Saitama, 3Department of Nursing, Aino University Junior College, 4Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan; 5Department of Psychiatry, Hofstra Northwell School of Medicine, NY, USA *These authors contributed equally to this work Abstract: There are studies reporting the negative impact of smartphone utilization on sleep. It is considered that reduction of melatonin secretion under the blue light exposure from smartphone displays is one of the causes. The viewing distance may cause sleep disturbance, because the viewing distance determines the screen illuminance and/or asthenopia. However, to date, there has been no study closely investigating the impact of viewing distance on sleep; therefore, we sought to determine the relationship between smartphone viewing distance and subjective sleep status. Twenty-three nursing students (mean age ± standard deviation of 19.7±3.1 years) participated in the study. Subjective sleep status was assessed using the Pittsburgh Sleep Quality Index, morningness–eveningness questionnaire, and the Epworth sleepiness scale. We used the distance between the head and the hand while holding a smartphone to measure the viewing distance while using smartphones in sitting and lying positions. The distance was calculated using the three-dimensional coordinates obtained by a noncontact motion-sensing device. The viewing distance of smartphones in the sitting position ranged from 13.3 to 32.9 cm among participants. In the lying position, it ranged from 9.9 to 21.3cm. The viewing distance was longer in the sitting position than in the lying position (mean ± standard deviation: 20.3±4.7 vs 16.4±2.7, respectively, P<0.01). We found that the short viewing distance in the lying position had a positive correlation to a poorer sleep state (R2=0.27, P<0.05), lower sleep efficiency (R2=0.35, P<0.05), and longer sleep latency (R2=0.38, P<0.05). Moreover, smartphone viewing distances in lying position correlated negatively with subjective sleep status. Therefore, when recommending ideal smartphone use in lying position, one should take into account the viewing distances. Keywords: smartphone, sleep, blue light, distanc
民事第一審判決書（最高裁判所ウェブサイト掲載）のXMLデータ(平成31年～令和2年言渡し分)
No full text最高裁判所ウェブサイト掲載の民事第一審判決書（平成31年～令和2年言渡分）をXMLデータ化したもの，及びそのスキー
Development of environment-friendly aquaculture technologies and practices
No full textThe significant role of aquaculture in providing food security has been recognized, not only through its contribution to food supply, but also through the promotion of economic and social well-being. Aquaculture is also considered as a relatively recent and underdeveloped sector as compared to agriculture and animal husbandry, and there is a huge, unfulfilled potential in many countries, particularly in the region. The recently concluded ASEAN-SEAFDEC Conference “Fish for the People” highlighted the importance of sustainable fisheries for regional food security, and the need for comprehensive and cooperative efforts, resolutions and plan of actions among all stakeholders. With the projected shortfall in the supply of fish and fishery products to meet the demands of an ever-increasing population, aquaculture is looked upon as a sustainable source of renewable food resources.
One of the main programs of the SEAFDEC Aquaculture Department (AQD) is geared towards the development of sustainable aquaculture that is technically feasible, economically viable, environment-friendly, and socially equitable. An important subprogram is the development of environment-friendly aquaculture technologies and practices. The objectives of the subprogram are: 1) to develop and promote efficient aquaculture systems and designs for maximum sustainable productivity; 2) to devise and determine appropriate design, equipment, and operation and management practices that optimize utilization of resources and inputs, minimize adverse impacts on the environment, and sustain biological/ecological diversity; 3) to demonstrate, verify, adopt, refine, and promote proven aquaculture technologies and practices; and 4) to advance the social, economic, cultural, and policy importance of the aquaculture sector at the local, national, and regional level. At present, the main research areas are in nutrient dynamics of aquaculture systems, feed and waste management, development of culture systems, including bioremediation strategies, conservation and sustainable utilization of resources for aquaculture, and socio-economic and policy issues in aquaculture. In addition, verification and refinement of developed aquaculture technologies, in support of re search and training activities, are conducted to explore the potential of aquaculture technologies for commercial adoption and demonstrate appropriate technologies and responsible aquaculture practices. The paper presents an overview of current research activities by the author, and with involvement of other researchers at SEAFDEC AQD, including future plans under this and related programs
« Parsadan Gorgijanidze’s Exile in Shushtar: A Biographical Episode of a Georgian Official in the Service of the Safavids ». Journal of Persianate Studies 1, 2, 2008, p. 218-229.
No full textAt the beginning of the article, Maeda states his opinion that many Safavid ġolāms were far from severing all ties with their homeland: here the Author agrees with the views of other modern Safavid scholars but he (rightly, in the opinion of the present reviewer) contradicts what one often reads in the scholarly literature concerning military slavery in the Muslim world in general. Maeda is also correct in stating that “by introducing the institution of the royal ġolāms, the Safavids imported..
The newly discovered historical materials of Goken Maeda (COMMEMORATION NUMBER for Prof. Yasuhiro Kawahigashi)
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