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In this study, the input and output parameters of potassium (K) for wheat season were collected from 2000 to 2011 to evaluate the nutrient cycling and balance in North Central China, the Middle and Lower Reaches of the Yangtze River and Northwest China. The results showed that the K fertilizer application rates for each region were 74.7, 102.9 and 50.6 kg K/ha, the K brought from previous crop were 99.5, 19.8 and 23.4 kg K/ha, and brought from seeding were 1.0, 0.8 and 0.7 kg K/ha, respectively. The K input from atmospheric deposition and irrigation were all considered zero. The K uptake by harvest in above-ground plant in North Central China, the Middle and Lower Reaches of the Yangtze River and Northwest China were 131.8, 159.9 and 119.8 kg K/ha. As a result, The K balance in North Central China showed surplus by 43.6 kg/ha, while in the Middle and Lower Reaches of the Yangtze River and Northwest China, the K balance were both deficiency by 36.4 and 45.1 kg/ha, even though it did not affect the crop yield. While it is suggested that we need to adjust the K fertilizer application in a long term, in order to maintain the sustainable soil fertility.

In this study, the input and output parameters of Phosphorus (P) for wheat production system were collected from the year 2000 to 2011 to evaluate the nutrient cycling and balances in North Central China, the Middle and Lower Reaches of the Yangtze River and Northwest China. The results showed that the P fertilizer application rates for each region were 44.5, 39.7 and 42.3 kg P/ha, the P brought from previous crop were 14.8, 1.6 and 2.6 kg/ha, and brought from seeding were 1.5, 1.0 and 0.9 kg/ha, respectively. The P input from atmospheric deposition and irrigation were considered zero. The P uptake by harvest in above-ground plant in North Central China, the Middle and Lower Reaches of the Yangtze River and Northwest China were 41.2, 53.2 and 17.0 kg/ha. As a result, the P balance in North Central China and Northwest China were both showing surplus by 19.6 and 28.8 kg/ha, and in the Middle and Lower Reaches of the Yangtze River showed deficiency. It is suggested that we need to adjust the P fertilizer input in China, in order to maintain the sustainable soil fertility and avoid the negative impact on the environment.

The platform of rural distance learning (PRDL) is an interactive tool used to farmers for the video training, interactive consulting, teaching and management with the features of resource integration, safe, and reliable. PRDL was dual-network transmission structure via the Internet and E-government network, covering all the Beijings towns and villages, which is applied media asset management technology to build a municipal teaching resource library. The problems of PRDL are solved such as complex network for rural areas, limited bandwidth resources and diverse user needs base on in-depth study of distance learning key technologies. It is for farmers learning modern agricultural technology to provide a strong support.

Crop monitoring play an important role in the management of agricultural production. This paper presents an integrated platform of crop condition monitoring and diagnosis based on internet of things, as well as its structure and function design. The platform adopted the technology of the internet of things; it achieved fine management of seed and cultivates process by the means of agriculture information real-time collection and monitoring. The platform has certain application value in many agriculture activities, such as livestock management, aquaculture and other and so on.

The platform of rural distance learning is an interactive tool used to farmers for the video training, interactive consulting, teaching and management with the features of resource integration, safe, and reliable. The platform was dual-network transmission structure via the Internet and E-government network, covering all the Beijing’s towns and villages, which is applied media asset management technology to build a municipal teaching resource library. The problems of the platform are solved such as complex network for rural areas, limited bandwidth resources and diverse user needs base on in-depth study of distance learning key technologies. The system was easy to deploy, highly scalable, and low cost operation. It is for farmers learning modern agricultural technology to provide a strong support.

To study the relationship between phosphatidylinositol-3-kinases(PI3K)/protein-serine-threonine kinase(AKt) signaling pathway and orthodontic tooth movement.Twenty-four rabbits were chosen to establish rabbit models for the study. The right maxillary teeth of each animal treated by orthodontics were as the test side, and the untreated left teeth were as the control side. The animals were sacrificed at 3, 5, 7, 14 d, respectively. The prepared tissue specimens were processed for the study. The changes of the expression of PI3K, AKt in periodontal tissues were detected by real-time quantitative-polymerase chain reaction (RQ-PCR) and Western blot techniques.RQ-PCR showed that the expression of PI3K, AKt mRNA dramatically changed at 3 d. The expression of PI3K, AKt mRNA in the test side was higher than the control side, especially at 7 d, and then decreased. Compared with the control side, there was statistical significant difference in the test side(P0.05). The study obtained consistent conclusion from Western blot and RQ-PCR.Expression of PI3K, AKt in rabbit periodontal tissues increase during orthodontic tooth movement, which prompts that PI3K/AKt signal pathways relate to orthodontic tooth movement and PI3K/AKt signal pathway involve in the periodontal tissue remodeling.

the traditional remote data collection has the shortcomings such as the cover scope is small and the corresponding is unreliable, and the wireless network communication has better timeless and does not have the space limitation. The remote data collection and supervisory system based on GPRS/3G (General Packet Radio Service/The 3rd generation communication) network is discussed and designed in the text. It discusses chiefly a scheme which uses JZ4730 microcontroller to control TC35i module and make use of MMS (Multimedia Messaging Service) and SMS (Short Messaging Service) to complete remote data collection and supervision, and supplies a design program of the hardware and software, and then a conclusion is given at the end of paper.

The change of endogenous superoxide dismutase (ESOD) during myocardial ischaemia and reperfusion and the efficacy of oxygen free radical scavengers in myocardial protection were investigated in an isolated heart model connected to a recirculating nonpulsatile perfusion circuit. Subjected to a two-hour period of global ischaemia at 27°C, the heart was reperfused at 37°C with oxygenated diluted autogenous blood for 60 minutes. Superoxide dismutase plus catalase were added to the cardioplegic solution and reperfusates. ESOD activity was measured by the pyrogallol method. Our experiment demonstrates that ESOD activity after ischaemia and reperfusion is decreased by the addition of free radical scavengers (SOD and CAT) to the cardioplegic solution and the reperfusates. In addition, SOD and CAT addition was also associated with reduced leakage of myocardial enzymes, reduced coronary vascular resistance and lessened ultrastructural damage to the myocardium. These results suggest that the use of SOD and CAT may inhibit myocardial reperfusion injury by scavenging oxygen-derived free radicals.