Uni-modal rainfall pattern has long dry spell wherein sweetpotato is scarce, expensive but cheap at harvest. The crop is mostly consumed, processed or sold. Extending shelf-life of roots is crucial for Malawi and Nort...Uni-modal rainfall pattern has long dry spell wherein sweetpotato is scarce, expensive but cheap at harvest. The crop is mostly consumed, processed or sold. Extending shelf-life of roots is crucial for Malawi and Northern Ghana as the crop has high value. Trials were conducted in the countries at the community level. In the dry season, temperature is cool in Malawi while warm in Ghana, but thru harmattan, the night is cool with low relative humidity. In Malawi, orange-fleshed sweetpotato Zondeni var., white and yellow types were assessed in three types of storage, Afghan ventilated pit store, storage in dry sand of pit-steps, and of a granary In Ghana, local moistened heap and sandbox were compared. In Malawi, weight losses were calculated relative to the quantity stored at start, it was not cumulative. At 1.5 months no significant difference was among treatments. By 3.5 months the pit-steps method emerged to be superior and continued to 6.5 months. Losses in granary were due to shriveling, in the pit-stepsdue to termites and rats, and in ventilated pit due to termites, rats and Java black rot. Sprouting was high in pit-steps, but it was simply removed and roots returned to storage. At 6.5 months, the beta-carotene of Zondeni roots was traceable. Farmers gained high price when selling them as roots were scarce. Women favored the pit-steps because it was manageable. In Ghana, the sandbox was superior to local moistened heap. Methods designed were suitable for home consumption, but will require modification for commercialization.展开更多
The Chinese government started a take restoration project in Poyang Lake region 10 years ago, and the expost mOnitor of the migrants＇ livelihoods was limited, This paper compares the composition difference of domesti...The Chinese government started a take restoration project in Poyang Lake region 10 years ago, and the expost mOnitor of the migrants＇ livelihoods was limited, This paper compares the composition difference of domestic income and domestic consumption between migration and non-migration villages in Poyang Lake region. The results show that the migrants＇ domestic income has increased in the last 10 years, which originated from the tncreasing trend of active and extensive rural labor migration, while the resettlement has not influenced the domestic income significantly. The resettlement stimulates younger farmers to work.far away from home whose wages contribute nearly 80% of domestic income, The resettlement decreases their savings due to higher expenditure of daily life for those who work far away from home, and higher expenditure of food for those who stay at home, losing cultivated lands with irrigation system for vegetable. On the other hand. the increase of rural labor migration leads the migrants who stay at home to have access to more cultivated lands for rice and cotton, and the farmers also apply more fertilizer in the same cultivated land for more agriculture products. The resettlement makes most of migrants spend their savings on the improvement of their housing conditions due to not enough governmental financial support for new building. After the analysis, some factors that influence migrants＇ income and consumption are discussed. The paper may contritbute to the building of Poyang Lake Ecological Economic Zone.展开更多
Vertigo is one of the most common clinical symptoms. However, the chemical processes involved in the pathological mechanism of vertigo remain to be fully understood. In this study, we investigate the dynamic changes i...Vertigo is one of the most common clinical symptoms. However, the chemical processes involved in the pathological mechanism of vertigo remain to be fully understood. In this study, we investigate the dynamic changes in the magnesium (Mg 2+ ) concentration in medial vestibular nucleus (MVN) of guinea pigs following vertigo induced by vestibular ice water stimulation with an electrochemical detection method consisting of in vivo microdialysis and on-line selective electrochemical detection. Electrochemical detection of Mg 2+ was accomplished based on the current enhancement of Mg 2+ towards the electrocatalytic oxidation of NADH at the electrodes modified with the polymerized film of toluidine blue O (TBO). Selectivity for the on-line electrochemical detection against Ca 2+ was achieved by using ethyleneglcol-bis(2-aminoethylether) tetraacetic acid (EGTA) as the selective masking agent for Ca 2+ . The basal level of the extracellular Mg 2+ in the MVN of guinea pigs was determined to be 759.7 ± 176.2 M(n = 16). Upon ice water irrigation of the left external ear canal, the concentration of Mg 2+ in the MVN decreases significantly, reaches 72 ± 6% (n = 8) of the basal level, and maintains for at least 1000 s. Control experiments reveal that neither warm water irrigation of the external ear canal nor ice water irrigation of the auricle induces the decrease in the concentration of Mg 2+ in the MVN. These results demonstrate that the extracellular Mg 2+ in the MVN decreases significantly following vertigo induced by vestibular ice water stimulation. This demonstration suggests that Mg 2+ might play an important role in the pathological mechanism of vertigo.展开更多
文摘Uni-modal rainfall pattern has long dry spell wherein sweetpotato is scarce, expensive but cheap at harvest. The crop is mostly consumed, processed or sold. Extending shelf-life of roots is crucial for Malawi and Northern Ghana as the crop has high value. Trials were conducted in the countries at the community level. In the dry season, temperature is cool in Malawi while warm in Ghana, but thru harmattan, the night is cool with low relative humidity. In Malawi, orange-fleshed sweetpotato Zondeni var., white and yellow types were assessed in three types of storage, Afghan ventilated pit store, storage in dry sand of pit-steps, and of a granary In Ghana, local moistened heap and sandbox were compared. In Malawi, weight losses were calculated relative to the quantity stored at start, it was not cumulative. At 1.5 months no significant difference was among treatments. By 3.5 months the pit-steps method emerged to be superior and continued to 6.5 months. Losses in granary were due to shriveling, in the pit-stepsdue to termites and rats, and in ventilated pit due to termites, rats and Java black rot. Sprouting was high in pit-steps, but it was simply removed and roots returned to storage. At 6.5 months, the beta-carotene of Zondeni roots was traceable. Farmers gained high price when selling them as roots were scarce. Women favored the pit-steps because it was manageable. In Ghana, the sandbox was superior to local moistened heap. Methods designed were suitable for home consumption, but will require modification for commercialization.
基金supported by the Key Projects in the National Science & Technology Pillar Program during 11th 5-year Plan Period of China (Grant No.2007BAC23B)
文摘The Chinese government started a take restoration project in Poyang Lake region 10 years ago, and the expost mOnitor of the migrants＇ livelihoods was limited, This paper compares the composition difference of domestic income and domestic consumption between migration and non-migration villages in Poyang Lake region. The results show that the migrants＇ domestic income has increased in the last 10 years, which originated from the tncreasing trend of active and extensive rural labor migration, while the resettlement has not influenced the domestic income significantly. The resettlement stimulates younger farmers to work.far away from home whose wages contribute nearly 80% of domestic income, The resettlement decreases their savings due to higher expenditure of daily life for those who work far away from home, and higher expenditure of food for those who stay at home, losing cultivated lands with irrigation system for vegetable. On the other hand. the increase of rural labor migration leads the migrants who stay at home to have access to more cultivated lands for rice and cotton, and the farmers also apply more fertilizer in the same cultivated land for more agriculture products. The resettlement makes most of migrants spend their savings on the improvement of their housing conditions due to not enough governmental financial support for new building. After the analysis, some factors that influence migrants＇ income and consumption are discussed. The paper may contritbute to the building of Poyang Lake Ecological Economic Zone.
基金financially supported by the National Natural Science Foundation of China (20975104, 20935005, 90813032, 21127901 for L. Mao, 91132708 for P. Yu)Beijing Municipal Natural Science Foundation (7082100 for F. Ma)
文摘Vertigo is one of the most common clinical symptoms. However, the chemical processes involved in the pathological mechanism of vertigo remain to be fully understood. In this study, we investigate the dynamic changes in the magnesium (Mg 2+ ) concentration in medial vestibular nucleus (MVN) of guinea pigs following vertigo induced by vestibular ice water stimulation with an electrochemical detection method consisting of in vivo microdialysis and on-line selective electrochemical detection. Electrochemical detection of Mg 2+ was accomplished based on the current enhancement of Mg 2+ towards the electrocatalytic oxidation of NADH at the electrodes modified with the polymerized film of toluidine blue O (TBO). Selectivity for the on-line electrochemical detection against Ca 2+ was achieved by using ethyleneglcol-bis(2-aminoethylether) tetraacetic acid (EGTA) as the selective masking agent for Ca 2+ . The basal level of the extracellular Mg 2+ in the MVN of guinea pigs was determined to be 759.7 ± 176.2 M(n = 16). Upon ice water irrigation of the left external ear canal, the concentration of Mg 2+ in the MVN decreases significantly, reaches 72 ± 6% (n = 8) of the basal level, and maintains for at least 1000 s. Control experiments reveal that neither warm water irrigation of the external ear canal nor ice water irrigation of the auricle induces the decrease in the concentration of Mg 2+ in the MVN. These results demonstrate that the extracellular Mg 2+ in the MVN decreases significantly following vertigo induced by vestibular ice water stimulation. This demonstration suggests that Mg 2+ might play an important role in the pathological mechanism of vertigo.
