Many studies related to greenhouse design have been conducted. This paper reviewed five results of research into the design of pipe-framed greenhouses (hereinafter pipe houses) using an investigation, numerical analysis and wind-tunnel test. The first and second studies showed how the pipe houses collapsed due to snow and wind load. The third study analyzed an economical and reasonable design for a typical pipe house subject to snow load. Seven numerical finite element models of simple pipe house were subject to stress and buckling analyses. In the fourth study, the distributions of wind pressure coefficient C_p, both external and internal, were evaluated in detail using a pipe-house model, based on a wind-tunnel experiment using 1:20 scale models in a turbulent boundary layer correctly simulating natural winds over typical open-country exposure. The fifth study investigated the effect of d_p, the distance between the side walls of pipe houses, on the distribution of C_p on two or three pipe houses arranged in parallel. The results of these studies are indispensable to establish safe and economical pipe-house designs.

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Land improvements in Japan involve the need to conserve ecosystems and biodiversity, hence research and research methods related to ecosystem conservation in rural aquatic areas are increasing and developing. Analysis in rural aquatic ecosystems using stable carbon and nitrogen isotope ratios is an important research method and such isotope ratios are used for various purposes when investigating rural ecosystems. Several characteristics of rural ecosystems have been found by stable isotope ratio analysis in Japan as described below. Food webs in drainage canals are derived from organic matter, comprising a mixture of algae and detritus attached to stones, whereas food webs in ponds originate from fallen leaves. In this study, it emerged that small food webs are sustained by various sources of materials in rural ecosystems. Quantitative results showed that most Japanese brown frogs move to secondary forests, where they feed and overwinter after metamorphosis or spawning. Micro food webs of web–building spiders differ from epigeal spiders because the carbon sources differ in terms of the secondary forest and levees, while the diversity of material flow in creatures of secondary forest ditches and the eco-tone between secondary forests and paddy fields was revealed by analyzing carbon stable isotope ratios. Analyzing stable isotope ratios in frogs indicates that frog populations include immigrants. Immigrants in reconstructed concrete canals cannot enter a new population, while the existence of immigrants in the population is evidence of dropping, washing and landing of frogs. This method can significantly boost the conservation of rural ecosystems by revealing the life processes of animals that are not well known.

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Nitrous oxide (N₂O), a strong greenhouse gas, is known to be emitted during the dairy manure composting process, so its emissions should be mitigated. Both pile-turning events and inappropriate use of mature compost containing NO_x^--N may cause N₂O emissions to soar, although using bulking agent appropriately can also reduce them significantly. Isotopomer analysis of emitted N₂O suggests that bacterial denitrification is the main process of N₂O production just after pile-turning events. Significant NO_x^--N is accumulated in the pile surface between the pile turnings, and β-proteobacterial ammonia-oxidizing bacteria is seemingly the main contributor to this accumulation. Because the amount of NO_x^--N accumulated in surface explains the N₂O production after mixing, denitrification of this accumulated NO_x^--N is the main source of significant production just after the turning events. Microbes in the pile core do not contribute to this N₂O production significantly, while denitrifiers in the compost surface seem to be the main producer of significant N₂O just after the pile-turning events. The bacterial community in the compost surface is always dominated by mesophiles, belonging to phylum Bacteroidetes and Proteobacteria. The future direction and mitigation strategy is discussed in detail based on these recent findings.

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This review describes our studies on compensatory growth, specifically the growth that occurs after dietary lysine deficiency is changed to sufficiency. We found that dietary lysine sufficiency induced compensatory growth in pigs after dietary lysine deficiency. We also showed that compensatory growth of pigs induced by dietary lysine sufficiency was partly attributed to greater N retention. In a rat model, both suppression of proteolysis and increased protein synthesis in skeletal muscle contributed to their compensatory growth with lysine sufficiency. Finally, our in vitro studies with cultured skeletal muscle cells revealed that the compensatory growth in these cells was induced by increased lysine levels in combination with the modulation of insulin-like growth factor-I and glucocorticoid levels. This suggested that compensatory growth in pigs and rats with lysine sufficiency was due to both increased serum lysine levels and changes in the levels of hormones involved in protein synthesis and degradation.

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In light of the logistical challenges for gearing production and conservation efforts to the scale of the smallholder, there is growing interest in promoting Integrated Irrigation-Aquaculture (IIA), such as rice-fish culture, which has strong potential in Sub-Saharan Africa. Available literature has stressed institutional shortcomings in providing necessary services, including extension, training, and credit-lending; ways in which farmers could craft new water-management regimes if these services were available have not been well studied and are key to successful farming integration. In this paper, we analyzed the conditions for achieving integrated water governance, with reference to the available evidence relating to the rice-fish system environment, investment incentives, collective action, and property rights. Our analysis suggests that the system design should be adapted to existing farm conditions to minimize topographical and technical modifications and maximize successful adoption of rice-fish culture. Labor and capital requirements must remain within the bounds of investment capacity, which is limited and seasonal among African smallholders. Investments in IIA should promise an adequate profit margin to secure reinvestment. Since reinvestment is important for the advanced operation and maintenance of water facilities, sustainable rice-fish farming requires strong accountability in organizing water distribution, monitoring, and related rule enforcements. Therefore, a preliminary need is to understand farmers’ socioeconomic characteristics and interests that affect participation and free riding.

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The buckwheat plant contains high levels of rutin (flavonol 3-O-rutinoside) in many organs, including its seeds, cotyledon, leaves, stem, and flowers. The enzymes that catalyze the decomposition and synthesis of rutin in buckwheat are unique in terms of having relatively low K_m values, indicating that buckwheat developed rutinosidase and glycosyl transferase enzymes specifically suited for rutin metabolism. In Tartary buckwheat seeds, high levels of rutin content and rutinosidase activity cause strong bitterness, which may effectively protect the seeds from being eaten by animals. The stress responses observed in buckwheat leaves suggests that rutin and rutinosidase are involved in enhancing the defense system against environmental stresses, including UV light, low temperature, and desiccation.

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To examine the effect of 2-azahypoxanthine (AHX) on rice plant (Oryza sativa L. cv. Nipponbare) growth, we carried out pot and field experiments. AHX was applied at 50 μM for two weeks at four growth stages (transplanting, tillering, panicle formation and ripening stages) in the pot experiment, and 1 mM AHX at three stages [at rising of seedling in nursery boxes (seedling treatment), transplanting and panicle formation stages] in the field experiment. Both pot and field experiments showed a tendency toward increased panicle number (PN), culm length (CL) and plant dry weights with AHX treatments. Brown rice yields were also improved by AHX treatments, especially when applying at stages of tillering and panicle formation and seedling and transplanting during pot and field experiments, respectively. In the latter, yield increased drastically up to 18.7, 15.8, 9.6 and 5.8% of control. However, panicle length and 1000-grain weight were not affected by AHX application. These results suggested that AHX increased the brown rice yield through its effects on PN and/or CL.

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Temporal changes in tocochromanols during the development of caryopsis in two barley cultivars, ‘Fiber-Snow’ and ‘Musashibo’, were determined. Alpha-tocopherol (Toc) in leaves dominated among eight tocochromanol isomers in the leaves and spikes of both cultivars; suggesting that the tocochromanol content of the barley plant as a whole may be affected by the α-Toc content in leaves. The pattern of temporal changes in leaf Toc content also differed between the cultivars. Leaf Toc content increased strikingly after anthesis in ‘Fiber-Snow’, whereas no conspicuous increase was observed in ‘Musashibo’. Toc content was also significantly higher in ‘Fiber-Snow’ than in ‘Musashibo’ during the milky and dough stages. Tocotorienols (T3) were exclusively present in the spikes. They occurred around ten days after anthesis, peaking after the milky stage, whereas Toc had already accumulated at the first heading date. Alpha-T3 was the dominant form of the T3s, the accumulation of which preceded those of the β- and γ-forms in both cultivars. Our findings revealed that the Toc content of the whole barley plant might remain high throughout caryopsis development, decreasing only toward the end and that T3 occurred after the mid-stage of the development. These results indicate that the current conventional harvest time for forage barley is appropriate, as farmers harvesting during caryopsis development will produce forage containing considerable tocochromanol.

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Zambia has frequently been affected by abnormal weather and droughts. Our research focused on the type of meteorological data required to assist farmers’ efforts to avoid the risks associated with these weather conditions. We conducted local meteorological observations from September 2007 to August 2010 at three sites in Sinazongwe District, Zambia. The three rainy seasons of this period coincided in sequence with La Niña (normal) and El Niño conditions. The mean annual precipitation for the three years of our study exceeded 1200 mm, which was considerably more than the regional annual average rainfall from 1970 to 2000 of around 800 mm per year. We used detailed analyses of intra-seasonal variations in other meteorological elements to attempt to explain the high precipitation. Local circulation dominated in our research area, while heavy rain induced by convection in the afternoon and night might account for precipitation exceeding the norm. We numerically simulated meteorological conditions over the past decade to determine whether the annual precipitation observed since September 2007 indeed exceeded the norm. Intra-seasonal variations in precipitation, such as high rainfall in December during the 2007/2008 rainy season, a gradual increase in cumulative precipitation through 2008/2009, and high rainfall in February in the 2009/2010 rainy season were possibly controlled by El Niño – Southern Oscillation. Our results suggest that annual variations in precipitation are common in this area and that the precipitation we observed did not necessarily exceed the norm.

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To obtain nutritional information for sugarcane cross-breeding aimed feed utilization, the morphological characteristics, chemical composition, and in situ dry matter degradability (DMD) of each of the ten accessions of Erianthus spp., Saccharum spontaneum and Saccharum spp. hybrids at 6 (6M) and 12 months (12M; after regrowth) were evaluated. For Erianthus spp. and S. spontaneum, the DMD at 48 h after incubation (DMD48h) and the corrected DMD48h (CDMD48h, expressed as DMD48h minus DMD0h) at 6M, exceeded those at 12M. Conversely, for Saccharum spp. hybrids, while the CDMD48h at 6M exceeded that at 12M, the DMD48h at 6M was lower than that at 12M. Compared to all other species, Saccharum spp. hybrids exhibited the highest DMD48h and CDMD48h. It was considered that a harvest with highest DMD could be obtained during the early growing stages in Erianthus spp. and S. spontaneum, but during a later growing stage in Saccharum spp. hybrids. DMD48h of Erianthus spp. correlated negatively with DM, NDFom and ADFom contents at 6 and 12 months after regrowth respectively. The ADL content of S. spontaneum correlated negatively with pooled DMD48h (r = -0.63; P < 0.01) and tended to correlate negatively with pooled CDMD48h (r = -0.47; P < 0.10). The NDFom and ADFom contents of Saccharum spp. hybrids correlated negatively with pooled DMD48h and positively with pooled CDMD48h, whereas these correlations were more affected by advancing maturity rather than the characteristics of accessions. These results suggest that DM and the fiber degradability of the accessions of genus Saccharum and Erianthus spp. could be estimated from certain chemical components, when selecting highly digestible accessions.

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The oxygen consumption rate (OCR) and ammonium excretion rate (AER) of a tropical sea cucumber, Holothuria scabra, were determined in laboratory experiments. OCR and AER exhibited a significant negative correlation to body weight (BW), expressed as a power function of BW: OCR = 0.09 × BW^−0.58 (mgO₂/g/h, r²=0.89, n=15) and AER = 0.38 × BW^−0.19 (μmolN/g/h, r²=0.54, n=15). These values were comparable to those in previous studies on other sea cucumber species. The OCR of shrimp tank sediment was reduced to less than half (4.5 ± 0.3 to 1.0 ± 0.1 mgO₂/gdry/h) by the ingestion and excretion process of H. scabra. Acid volatile sulfide (AVS-S) concentration was also decreased to less than half (0.67 to 0.31 mgS/mgdry); despite the low reduction rates of organic carbon and nitrogen contents (0.19 to 0.14 mgC/mgdry and 0.022 to 0.019 mgN/mgdry, respectively). These results suggest that components in the sediment with high oxygen consumption potential were removed by H. scabra. These findings also provide fundamental information with which to evaluate the quantitative role of H. scabra in polyculture with shrimp.

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