Time filter

Source Type

Gao W.,Chinese Academy of Forestry | Bai S.,Northeast Forestry University | Li Q.,Chinese Academy of Forestry | Gao C.,Northeast Forestry University | And 3 more authors.
PLoS ONE | Year: 2013

Late embryogenesis abundant (LEA) genes were confirmed to confer resistance to drought and water deficiency. An LEA gene from Tamarix androssowii (named TaLEA) was transformed into Xiaohei poplar Populus simonii. Twenty-five independent transgenic lines were obtained that were resistant to kanamycin, and 11 transgenic lines were randomly selected for further analysis. The polymerase chain reaction (PCR) and ribonucleic acid (RNA) gel blot indicated that the TaLEA gene had been integrated into the poplar genome. The height growth rate, malondialdehyde (MDA) content, relative electrolyte leakage and damages due to salt or drought to transgenic and non-transgenic plants were compared under salt and drought stress conditions. The results showed that the constitutive expression of the TaLEA gene in transgenic poplars could induce an increase in height growth rate and a decrease in number and severity of wilted leaves under the salt and drought stresses. The MDA content and relative electrolyte leakage in transgenic lines under salt and drought stresses were significantly lower compared to those in non-transgenic plants, indicating that the TaLEA gene may enhance salt and drought tolerance by protecting cell membranes from damage. Moreover, amongst the lines analyzed for stress tolerance, the transgenic line 11 (T11) showed the highest tolerance levels under both salinity and drought stress conditions. These results indicated that the TaLEA gene could be a salt and drought tolerance candidate gene and could confer a broad spectrum of tolerance under abiotic stresses in poplars. © 2013 Gao et al. Source

Guo Z.,The Open University of China | Guo Z.,Applied Technology Internet | Liu Y.,Chinese Institute of Scientific and Technical Information
ICIC Express Letters, Part B: Applications | Year: 2015

Scientific literature contains a great number of mathematical formulas, and the contexts of these formulas involve images, symbols and texts that are typical multimodal data. These multi-modal information helps users more fully understand the meaning of mathematics. This research presents a mathematical formula extraction procedure which uses natural language processing techniques to analyze the multi-modal information, and then uses the analyzed data to tag and regulate mathematical formulas. This provides more information than traditional recognition methods in that it can enhance the reproducibility of the structure of a mathematical formula, as well as can help to accurately understand the meaning expressed by the mathematical formula. © 2015 ICIC International. Source

Sun Z.J.,The Open University of China | Dai J.T.,Chinese Naval Aeronautical Engineering Academy
Advanced Materials Research | Year: 2014

For research on comprehensive performance of crankshaft in piston compressor, multi-body dynamics model was built to get mechanical boundary conditions of the crankshaft, and the fatigue strength was verified; Finite element model (FEM) of the crankshaft was established, and the 1st 6 modal of the crankshaft was obtained. The results showed that fatigue strength and dynamic characteristic of the crankshaft was qualified. Theoretical basis could be provided for optimize the crankshaft's structure by fatigue strength and modal analysis. © (2014) Trans Tech Publications, Switzerland. Source

Li Y.,The Open University of China
Communications in Computer and Information Science | Year: 2013

Since MIT OCW evoked a worldwide OER movement, many higher educational institutions have taken actions to consider how to take advantages of the initiatives. The concept of sharing high quality educational resources to promote education equality is widely accepted, but how to maintain sustainable development of OER challenges every university. This paper will review the mainland China's practical exploration with regards to creation and application of OER. It will narrate both government-supported projects and institutional actions to present achievements and problems. Based on some surveys and observations, the author will identify two major influential factors of policy and capacity and try to find out solutions to overcome the obstacles and facilitate the great undertaking. © Springer-Verlag Berlin Heidelberg 2013. Source

Qu Y.,Shandong University of Finance and Economics | Jiang G.,Beijing Normal University | Zhang F.,China Agricultural University | Zhao T.,The Open University of China
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2013

According to calculations from the Ministry of Land and Resources, the area of rural residential land in China is about 270 million acres at present, which is 5 times as much as that of urban construction land. The structure of urban and rural construction land is, therefore, seriously unbalanced. At the same time, there are a series of problems associated with rural residential land in China, such as diversified utilization patterns and inefficient utilization of land resources. How to improve the intensive use of rural residential land and alleviate the contradiction between supply and demand of construction land in urban and rural areas has become an important issue for the sustainable land use. To that end, there have been a variety of policies made for addressing these problems, e.g., connecting an increase in urban construction with a decrease in rural residential land (for short "CUR"), which would be an effective measure to promote the overall efficiency for rural residential land, improve rural production and living conditions, optimize the urban and rural land use structure and alleviate the shortage in land for urban construction. From the view of policy requirements and practice experience, setting up reasonable project zones is the core content of CUR planning. Taking Pinggu District of Beijing as a case, this paper attempts to evaluate the suitability intensity of urban new construction land and old rural residential land demolition using supply-demand theory, differential rent theory, and previous research on rural residential land consolidation potential and CUR zoning., Then, the results of evaluations were fixed respectively by the general plan for the land use and evaluation blocks' space relative concentration and suitability consistency, and the new urban building area and the old rural demolition area were selected. Through the establishment of the spatio-temporal interaction relationship principle and concept model, the CUR project zones were formed by organic combination. There are several results that follow. First, the method can effectively filter out the new building areas of urban construction and the dismantled areas of rural residential land, and then realize the composite joint and Spatio-temporal allocation so as to provide reference for the conditions setting and choice and spatial linkage and scheduling of CUR project zones. Second, overall, Pinggu district belongs to the supply exceeding demand CUR type, the supply potential of rural residential land consolidation potential can meet the demand of town new construction land. Third, the CUR plots are planned to 22 project zones in Pinggu district, including 8 recent project zones and 14 forward project zones in the sequence, and including 17 project zones in individual town and 5 project zones in different town in the space pattern. Fourth, based on the defining CUR project zones, with the reasonable analysis of building the new uses and effective arrangement and setting of depreciation and resettlement of rural residential areas, the paper realizes the integrative target to ensure the economic-social rapid development and promote more intensive utilization of land and increase quantity of cultivated land. Source

Discover hidden collaborations