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The phase referencing Very Long Baseline Interferometry (VLBI) technique is a newly developed tool to measure the angular position of a deep space exploration probe in the plane-of-the-sky. Through alternating observations between the probe and a nearby reference radio source, their accurate relative angular separation can be obtained from the radio images generated by this technique. To meet the requirements of the current orbit determination software, differential delay should be firstly derived from those radio images. A method to resolve the differential phase delay from the phase referencing VLBI technique is proposed in this paper, and as well the mathematical model for differential phase ambiguity resolution is established. This method is verified with practical measurement data from the Chang’E-3 mission. The differential phase delay between the Chang’E-3 lander and rover was derived from the phase referencing VLBI measurements, and was then imported into the Shanghai astronomical observatory Orbit Determination Program (SODP) to calculate the position of the rover relative to the lander on the lunar surface. The results are consistent with those acquired directly from radio images, indicating that the differential phase ambiguity has been correctly resolved. The proposed method can be used to promote applications of the phase referencing VLBI technique in future lunar or deep space explorations, and more accurate orbit determination becomes promising.

The present study was designed to investigate the relationship among epigenetic changes in Wnt antagonists, histone H4K20me1 and the expression of tumor-suppressor genes in acute leukemia (AL) to better understand the pathogenesis of leukemia. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect messenger RNA (mRNA) expression levels of Wnt antagonists (Wnt5a, HDPR1, DKK1 and DKK3) in patients with AL and in normal controls; pyrophosphate sequencing was performed to detect the methylation status of the Wnt5a promoter; and western blotting was performed to detect the overall expression levels of Wnt5a protein and histone H4K20me1 in patients with acute myeloid leukemia (AML) and in normal controls. The relationship between Wnt5a protein expression and histone H4K20me1 was analyzed. Chromatin immunoprecipitation-qPCR (ChIP-qPCR) was performed to investigate the recruitment of H4K20me1 and SET8 to the Wnt5a promoter and coding regions. Our results demonstrated that the expression levels of Wnt antagonists were generally low in AML, but showed differential expression in acute lymphocytic leukemia (ALL). In most cases of AML, methylation of the Wnt5a promoter was observed and Wnt5a protein expression was low. In some cases of AML, the overall level of H4K20me1 protein was higher than that in normal controls. In addition, Wnt5a expression was positively correlated with H4K20me1 expression and was unrelated to the methylation status of its promoter. Moreover, H4K20me1 and SET8 were enriched in the Wnt5a promoter region and coding region. By contrast, Wnt5a expression was unrelated to H4K20me1 expression in normal controls. Moreover, we observed that the methylation of Wnt antagonists was often found in patients with AL, particularly those with AML, whereas the extent of methylation was variable in ALL patients. Wnt5a expression was positively correlated with the enrichment of H4K20me1 and SET8 at the Wnt5a promoter and coding regions. H4K20me1 increased Wnt5a expression by promoting transcription initiation and elongation.

To detect the abnormal methylation of the CPG island in the suppressor gene promoter region of the Wnt signaling pathway in cell strain NB4 of the acute promyelocytic leukemia by using the bisulfite sequcucing PCR(BSP), to screan the hyper-methylated suppressor gene of the Wnt signaling pathway and to evaluatc the potency of BSP in the methylation study.The strain NB4 cells of the acute promyelocytic leukemia patients were used as the object, the mononuclear cells from 20 normal persons were used as the controls. The DNA was extracted and processed by bisulfite, the target sequences were amplified with PCR, then the abnormal methylation of the suppressor genes of the Wnt signaling pathway in the NB4 cells was analyzed by BSP, and the advantage and disadvantage of BSP were evaluated by comparison with the Methylation specific PCR and Pyrosequencing.The methylated rate of suppressor genes of the Wnt signaling pathways in the NB4 cells detected by BSP was as follows: the gene WIF1 95.26%, the gene DKK3 86%, the gene SFRP1 81.67%, the gene SFRP2 95.71%, the gene SFRP4 85%, and the gene SFRP5 95%; while the methylations in the control group were respectively as follows: the gene WIF-1 1.5%, the gene DKK3 4.2%, the gene SFRP1 0%, the gene SFRP2 0.9%, the gene SFRP4 2.5%, and the gene SFRP5 1.75%. A more significant methylation happened in the suppressor genes promoter of the Wnt signaling pathway in the NB4 cells as compared with the control group.Many hypermethylated suppressor genes are found in the Wnt signaling pathway of the acute promyelocytic leukemia NB4 cells, which may be served as one of the early diagnosis index and therapeutic target of the acute promyelocytic leukemia.

An information consensus algorithm for high-order multi-agent systems is proposed based on algebraic graph theory. Sufficient and necessary conditions are given for each information to converge to common values. The network topology of multi-agent systems has a directed spanning tree and each weight of different derivatives is positive, then consensus is achieved.

In this Study, Visible on the Far-infrared Emissivity of Knitted Fabric, its Rate of Change of Far Infrared Radiation Were Observed. in this Study, Light Exposure Time for 20,40,60 Minutes, the Experimental Results, the Longer the Kind of Light Source Distribution Is much Higher Surface Temperature Will Be Relatively Higher Rate of Infrared Radiation, when the Light Source when the Suspension Began Measuring Data, the Light Source, the Far Infrared Radiation Rate of about 0.941 ~ 0.975 when Reached Will Begin to Flatten, after 15 Minutes Returned to its Emission Rate of about 0.937, when the Far-infrared Light Irradiation of Polyester Fabrics through the Far Infrared Radiation Values Are Effectively Increase, so the Light Irradiation Intensity of Far Infrared Radiation Rate of the Subjects Were Characterized by Light and the Length of Time to Improve the Fabric Surface Temperature Change and this Temperature Rise Is the Key to the Experimen

Flight path planning of UAV is a complicated optimum problem. The research in this field is usually classified as two directions: optimal path planning without considering the computation cost and real-time suboptimal path planning. Aimed at the two problems, this paper presents two methods of path planning of UAV. One method is based on heuristically search. In this method, we search the threat net by using A-star algorithm. A shortest suboptimum path is obtained, which is composed of the lines on the Voronoi diagram, and then considering the UAV's turn constraint, the path can be smoothed by geometry method. The other method is based on genetic algorithm and potential fields technology. Because potential fields, however popular, have shortcomings, viz, trap situations due to local minima, the genetic algorithm is introduced. In this method, Firstly, construct the threats' Delaunay triangle net based on the principle of nearest neighborhood and a safe planning path goes across the lines of the triangles. Then designate each point (position of a threat) on the left of the path a index 0 and on the right 1 and only designate the points of line which is not passed the same symbol. Thus, based on the directions of passing the lines of Delaunay triangle, a kind of encoding is designed on the principle of "Left 0, Right 1". At last, a global planning path can obtained by the genetic algorithm and potential fields technology. At the same time, simulation results of the two path planning methods are given.