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排序方式: 共有635条查询结果,搜索用时 703 毫秒
91.
92.
Tran Thi Thu Hoai Hiroaki Matsusaka Yoshiko Toyosawa Tran Danh Suu Hikaru Satoh Toshihiro Kumamaru 《Breeding Science》2014,64(2):142-148
Amylose content is one of the most important factors influencing the physical and chemical properties of starch in rice. Analysis of 352 Vietnamese rice cultivars revealed a wide range of variation in apparent amylose content and the expression level of granule-bound starch synthase. On the basis of single-nucleotide polymorphisms (SNP) at the splicing donor site of the first intron and in the coding region of the granule-bound starch synthase I gene, Waxy gene, alleles can be classified into seven groups that reflect differences in apparent amylose content. The very low and low apparent amylose content levels were tightly associated with a G to T in the first intron whereas intermediate and high amylose was associated with a T genotype at SNP in exon 10. The correlation between the combination of T genotype at SNP in the first intron, C in exon 6, or C in exon 10 was predominant among low amylose rice varieties. Our analysis confirmed the existence of Wxop allele in Vietnamese rice germplasm. The results of this study suggest that the low amylose properties of Vietnamese local rice germplasm are attributable to spontaneous mutations at exons, and not at the splicing donor site. 相似文献
93.
A simulation was carried out by using a 3D numerical model for estimate the nutrient level discharged from striped catfish, Pangasianodon hypophthalmus intensively farming in the Mekong River, Vietnam. The simulated period was dry season from April 24, 2007, to April 27, 2007. Both dissolved and particulate forms of nutrients were simulated. A real status of water environment and scenario of discharge after applying fishpond effluent for irrigation of rice field were estimated in My Hoa Hung fish farm, An Giang Province. Simulated results were verified by observed data. Our results showed that nutrient levels at farming area in dry season were temporarily high and local. Applying waste water from the fishpond for irrigation of rice field could greatly reduce nutrients level in the fish farming area, the nutrient levels were 77 % for total nitrogen and 73 % for phosphorus. Therefore, recycling nutrient from fishpond effluent for irrigation of rice field illustrated an effective technology for pollution reduction which is a crucial issue to enable sustainable development of intensively farmed striped catfish. 相似文献
94.
95.
Undernutrition in the parental and first generation provokes an organ‐specific response to oxidative stress on neonates of second filial generation of Wistar rats 下载免费PDF全文
R. Baños‐Gómez N. S. Cruz‐Cansino T. Suarez‐Diéguez C. Valadez‐Vega E. Ramírez‐Moreno E. Alanís‐García J. A. Ariza‐Ortega J. J. Manríquez‐Torres E. Zamora‐Romo L. Delgado‐Olivares 《Journal of animal physiology and animal nutrition》2017,101(2):267-274
Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second‐generation neonates (F2) of undernourished rats. For this purpose, both parents in parental (F0) and first generation (F1) were fed with a low‐nutrient diet. Body mass and length decreased (p < 0.05) in F0, F1 and F2 being the F1 males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F2 neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ‐specific response, on F2 neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions. 相似文献
96.
De Ngoc Nguyen Truc Thanh Nguyen Quy Ngoc Tran Tuong Phuc To Dung Van Tran 《Communications in Soil Science and Plant Analysis》2017,48(6):615-623
Acid sulfate soils (ASS) are characterized by low pH, aluminum (Al), and iron (Fe) toxicity and are typically deficient in phosphate (PO4). The application of phosphorus (P) fertilizer could help reduce the level of exchangeable Al and Fe, thereby improving the rice growth and yield. Five levels of P (0, 20, 40, 60 and 80 kg phosphorus pentoxide (P2O5)/ha) were tested with rice varieties MTL560 in the wet season and MTL480 in the dry season. The optimum rate of P was 60 kg P2O5/ha for rice in the dry season and 80 kg P2O5/ha in the wet season. Soil testing showed at the start of the season that there was sufficient P in the soil. At the end of the season there was a reduction in soil Al and Fe in plots that had P rates above 40 kg P2O5/ha. It is therefore likely that P application reduced Al and Fe toxicity through precipitation and formation of Al-P and Fe-P compounds, which boasted yield, rather amending a soil P deficiency. 相似文献
97.
98.
Malika Bendouz Justine Dionne Lan Huong Tran Lucie Coudert Guy Mercier Jean-François Blais 《Water, air, and soil pollution》2017,228(3):115
This study was conducted to determine the optimal conditions for PAH degradation from highly contaminated attrition sludge (PAC) using a Fenton process or successive permanganate (KMnO4) oxidation and Fenton processes. The following parameters were studied to optimize the Fenton oxidation process: the amounts of reactants based on the stoichiometric oxidant demand (SOD), the reactant addition protocol and number of doses, and the solid/liquid ratio (S/L). The results showed that the following conditions were optimum: TS?=?30%, 7.5 times SOD, H2O2/Fe2+ ratio?=?10, and added five times during 60 min, which allowed the degradation of 43% of total 27 PAHs from the PAC. Successive Fenton and KMnO4 oxidation processes were also tested. PAH degradation using a sequential Fenton process followed by KMnO4 oxidation (or KMnO4 followed by Fenton) was higher than for the use of Fenton or KMnO4 treatment alone. Up to 71% of the total 27 PAHs were degraded when using a combination of both processes. It appeared that the sequential treatment is a viable method for the significant degradation of 27 PAHs from PAC (t value?>?2.77). 相似文献
99.
Hai Nguyen Tran Chung-Kung Lee Mai Thi Vu Huan-Ping Chao 《Water, air, and soil pollution》2017,228(10):401
Spherical biochar derived from saccharides (glucose, sucrose, and xylose) was prepared through two steps: pre-hydrothermal carbonization at 190 °C and calcination at low temperatures (200–325 °C). The spherical biochar was characterized by Brunauer–Emmett–Teller (BET) surface area analysis, Fourier transform infrared spectroscopy, zeta potential, scanning and transmission electron microscopies, and X-ray diffraction. The result indicated that the spherical biochar exhibited low S BET (15–22 m2/g), but abundant superficial active oxygen-containing functional groups. The spherical biochar possessed a negatively charged surface within solution pH 2.0–11. The adsorption process of Pb2+, Cu2+, and methylene green 5 (MG5) was strongly dependent on the solution pH and reached fast equilibrium at approximately 60 min. The maximum Langmuir adsorption capacity (Q°max) exhibited the following order: glucose-biochar > sucrose-biochar > xylose-biochar prepared at 300 °C. The selective adsorption order of glucose-biochar was Cu2+ (0.894 mmol/g) > Pb2+ (0.848 mmol/g) > MG5 (0.334 mmol/g). The electrostatic attraction played a determining role in the adsorption mechanism of pollutant cations. The adsorption of anionic dye (acid red 1) on the spherical biochar was negligible because of electrostatic repulsion. The spherical biochar can serve as a newer and promising adsorbent to remove toxic pollutant cations from water media. 相似文献
100.
Ha Duy Truong Chong Ho Wang Tran Trung Kien 《Communications in Soil Science and Plant Analysis》2017,48(14):1701-1709
This research was conducted to investigate the effects of different medium compositions on physicochemical properties and the growth of two tomato varieties. Five treatments were applied, combining medium composition with rice husk ash (RHS) and coconut fiber (CF) with the following proportions: 1/3 Peat moss + 1/3 rice husk ash + 1/3 coconut fiber (T1); 1/3 Vermicompost + 1/3 rice husk ash + 1/3 coconut fiber (T2); 1/3 Cattle manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T3); 1/3 Chicken manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T4); 1/3 Hog manure compost + 1/3 rice husk ash + 1/3 coconut fiber (T5). The results demonstrated that between pH, electrical conductivity (EC) value, and nutrient content in the media, there was a significant difference that led to different concentrations of total macro- and micronutrients in the shoots of both varieties. In addition, the root weight, shoot weight, and root volume were affected by medium composition for two varieties in seedling stage. A mixture of cattle manures composted with RHS and CF under the rate (1:1:1 by volume), respectively, gave the highest value of germination rate, plant height, leaf number, and plant biomass. Medium composition significantly influenced the germination rate and elongation of seedlings, specifically for each tomato variety. Therefore, cattle manure compost as a medium supplement improves seedling quality and growth of the two tomato varieties. 相似文献