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Paddy and Water Environment - Two consecutive pilot-scale experiments were conducted to investigate the potential reuse of treated municipal wastewater (TWW) as an irrigation source for cultivating...  相似文献   
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To clarify the significance of fecal organic anions in neonatal diarrhea, a total of 252 fecal samples (91 diarrheic, 161 normal) were collected from 136 dairy calves (including three crossbreds) less than 4 weeks old. Fecal pH, D‐ and L‐lactate, succinate and volatile fatty acid (VFA) were analyzed. In normal feces, lactate was highest and VFA was lowest at week 1 of age, and lactate progressively decreased and VFA progressively increased with advancing age. In diarrheic samples, although higher pH and lower lactate levels were confirmed at week 1, samples at weeks 3–4 showed lower pH and VFA accompanied by higher lactate of D and L‐isomers. In diarrhea, fecal butyrate was significantly lower at all stages, but succinate levels did not differ significantly. The proportion of lactate to organic anions (sum of lactate, succinate and VFA) in diarrheic feces was lower at week 1, and higher in weeks 2–4, while that of VFA to organic anions showed the opposite pattern. Strong relationships were observed between fecal pH and lactate, and VFA proportions in organic anions, though the relationship was weak in diarrhea. Most of the elevated lactate was observed in fecal samples with lower VFA. However, succinate had no relationship with VFA or lactate levels.  相似文献   
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不同栽培法和收割期对甘蔗单产及含糖量影响的分析   总被引:2,自引:0,他引:2  
本研究利用1975~2008年33年间日本南大东岛甘蔗生产数据, 分析了甘蔗栽培方法[新苗种植(包括夏植和春植)、宿根]和收割时期对其产量、品质和经济性的影响.结果表明, 不同栽培法甘蔗多年平均产量依次为夏植>宿根>春植; 新植甘蔗的种植期越早产量越高; 宿根甘蔗产量与前茬甘蔗的收割期呈二次函数曲线关系, 前茬甘蔗收割过早或过迟均对宿根甘蔗生长不利; 宿根甘蔗产量随宿根次数增加呈下降趋势; 宿根甘蔗含糖量通常高于新植甘蔗, 且不同栽培法下3月下旬前收获的甘蔗含糖量随收割期后延而逐渐增加.在此基础上, 建立了依据栽培方法、收割时期预测甘蔗单产和含糖量的数学模型, 模型对我国甘蔗种植业具有理论和实际的参考价值.  相似文献   
4.
To clarify the relationship between cellular immune status and nutritive condition in periparturient dairy cows, feeding content, blood profiles, and immune condition were observed in cows from two dairy herds with different types of feed content. Immunological analyses such as leukocyte population and peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, TNF-alpha, IL-4, and IL-10, quantified by real-time RT-PCR were performed. With regard to feed content during dry periods, there were six cows in the herd with insufficient non-structural carbohydrate (NFC) intake (group I) and six cows in the herd with sufficient NFC intake (group II). Significantly lower levels of blood glucose were observed in group I between weeks -12 and 16 compared with group II. Serum cholesterol level was significantly lower in group I between weeks 2 and 10 than in group II. The numbers of CD3+ and CD4+ T cells in group I were significantly lower than those in group II in weeks 6 and 14. The numbers of CD21+ B cells were significantly lower in group I than in group II in weeks -16, -12, 2, and 10. On the other hand, the CD4+/CD8+ ratio in group II was significantly higher than group I between weeks 2 and 14. The IFNgamma/IL-4 mRNA rate in group I was significantly lower than group II in week 6. We concluded that cellular immune depression occurrs after calving in dairy cows with low nutritional status in the periparturient period.  相似文献   
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Controlled self-assembly of a trinitrofluorenone-appended gemini-shaped amphiphilic hexabenzocoronene selectively formed nanotubes or microfibers with different photochemical properties. In these nanotubes, which are 16 nanometers in diameter and several micrometers long, a molecular layer of electron-accepting trinitrofluorenone laminates an electron-donating graphitic layer of pi-stacked hexabenzocoronene. The coaxial nanotubular structure allows photochemical generation of spatially separated charge carriers and a quick photoconductive response with a large on/off ratio greater than 10(4). In sharp contrast, the microfibers consist of a charge-transfer complex between the hexabenzocoronene and trinitrofluorenone parts and exhibit almost no photocurrent generation.  相似文献   
8.
High-resolution images of the surface of asteroid Itokawa from the Hayabusa mission reveal it to be covered with unconsolidated millimeter-sized and larger gravels. Locations and morphologic characteristics of this gravel indicate that Itokawa has experienced considerable vibrations, which have triggered global-scale granular processes in its dry, vacuum, microgravity environment. These processes likely include granular convection, landslide-like granular migrations, and particle sorting, resulting in the segregation of the fine gravels into areas of potential lows. Granular processes become major resurfacing processes because of Itokawa's small size, implying that they can occur on other small asteroids should those have regolith.  相似文献   
9.
This study was conducted to investigate the effects of salinity stress and flower number on growth, yield, water use efficiency (WUE), and fruit quality of cherry tomatoes cultivated under soilless conditions. The experiment was conducted in a plastic house (5-m wide × 11-m long) located in Gifu University. The seedlings were transplanted in a randomized complete block design with six plants per treatment (NT1 and ST1 were with four plants), giving a total of 44 plants in 22 pots (two plants per pot). Two different salinity levels [no-salinity and salinity with electrical conductivity: 0.8 and 3.0 dS m?1, respectively] and four flower number treatments (8, 13, 18, and free per truss) were investigated in the experiment. The results showed that salinity stress negatively affected tomato growth, yield, and marketable yield, but improved tomato fruit quality. The number of flowers had no effect on tomato growth variables and WUE, but the yield significantly increased with increasing flower number. However, the fruit quality was decreased with increased flower number. A reasonable control for fruit load can increase marketable yield in commercial cultivation. Under salinity stress conditions, properly increasing the number of flowers can avoid yield reduction.  相似文献   
10.
This research has experimentally investigated the interactive influences of salinity stress and leaf thinning on the growth, yield, water use efficiency, and fruit quality of cherry tomatoes cultivated under soilless conditions. The experiment was conducted in a plastic house (width of 5 m and length of 11 m) located in Gifu University. The seedlings were transplanted in a randomized complete block design with six plants per treatment, and a total of 36 plants in 18 pots (two plants per pot). The experiment received salinity treatment (no-salinity and salinity with electrical conductivity (EC) of 0.8 dS m?1 and 3.0 dS m?1, respectively) and leaf thinning treatment (no leaf thinning, basal leaf thinning and intersegment leaf thinning except the closest two). The experimental results showed that salinity stress negatively affected the growth, yield, marketable yield and water use efficiency of cherry tomatoes, but positively affected the fruit quality. Basal leaf removal significantly decreased the biomass, chlorophyll, and yield but significantly improved the fruit quality; that basal leaf removal coupled with salinity stress showed no influence on plant growth, but reduced the yield and greatly improved the fruit quality. Besides, tender leaves around truss removal significantly decreased the biomass, chlorophyll, yield, and water consumption, but improved the fruit quality; that tender leaves around truss removal coupled with salinity stress greatly decreased the biomass, chlorophyll, yield, and water consumption, but significantly improved the fruit quality.  相似文献   
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