Comparisons of Production Costs of Japonica Rice Between China and Korea

( Wei Guang Pan ),( Chung Gil Chung ) 한국농촌경제연구원 2004 Journal of Rural Development Vol.27 No.2

In order to compare the comparative advantage of japonica between China and Korea, the study analyzes the production cost. After comparing the cost and its structure, it is found that the production of Japonica in China has more comparative advantage obviously. But the increasing rate is much higher than that of Korea in recent 10 years. In the long term, the gap between two countries will become smaller, while the inferior advantage of Korea can`t be changed during short-mid term. Some measures should be adopted to develop the competitiveness of japonica in Korea, such as, adjusting agricultural structure, enlarging the land scale and making quality differentiation.

Analysis the role of arabidopsis CKRC6/ASA1 in auxin and cytokinin biosynthesis

Dong-Wei Di,Lei Wu,Pan Luo,Li Zhang,Tian-Zi Zhang,Xue Sun,Shao-Dong Wei,Chen-Wei An,Guang-Qin Guo 한국식물학회 2016 Journal of Plant Biology Vol.59 No.2

The crosstalk between auxin and cytokinin (CK) is important for plant growth and development, although the underlying molecular mechanisms remain unclear. Here, we describe the isolation and characterization of a mutant of Arabidopsis Cytokinin-induced Root Curling 6 (CKRC6), an allele of ANTHRANILATE SYNTHASE ALPHA SUBUNIT 1 (ASA1) that encodes the á-subunit of AS in tryptophan (Trp) biosynthesis. The ckrc6 mutant exhibits root gravitropic defects and insensitivity to both CK and the ethylene precursor 1-aminocyclopropane-1-carboxylicacid (ACC) in primary root growth. These defects can be rescued by exogenous indole-3-acetic acid (IAA) or tryptophan (Trp) supplementation. Furthermore, our results suggest that the ckrc6 mutant has decreased IAA content, differential expression patterns of auxin biosynthesis genes and CK biosynthesis isopentenyl transferase (IPT) genes in comparison to wild type. Collectively, our study shows that auxin controls CK biosynthesis based on that CK sensitivity is altered in most auxin-resistant mutants and that CKs promote auxin biosynthesis but inhibit auxin transport and response. Our results also suggest that CKRC6/ASA1 may be located at an intersection of auxin, CK and ethylene metabolism and/or signaling.

Evolution of the Mir-155 Family and Possible Targets in Cancers and the Immune System

Xie, Guang-Bing,Liu, Wei-Jia,Pan, Zhi-Jun,Cheng, Tian-Yin,Luo, Chao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

The mir-155 family is not only involved in a diversity of cancers, but also as a regulator of the immune system. However, the evolutionary history of this family is still unclear. The present study indicates that mir-155 evolved independently with lineage-specific gain of miRNAs. In addition, arm switching has occurred in the mir-155 family, and alternative splicing could produce two different lengths of ancestral sequences, implying the alternative splicing can also drive evolution for intragenic miRNAs. Here we screened validated target genes and immunity-related proteins, followed by analyzation of the mir-155 family function by high-throughput methods like the gene ontology (GO) and Kyoto Eneyclopedin of Genes and Genemes (KEGG) pathway enrichment analysis. The high-throughput analysis showed that the CCND1 and EGFR genes were outstanding in being significantly enriched, and the target genes cebpb and VCAM1 and the protein SMAD2 were also vital in mir-155-related immune reponse activities. Therefore, we conclude that the mir-155 family is highly conserved in evolution, and CCND1 and EGFR genes might be potential targets of mir-155 with regard to progress of cancers, while the cebpb and VCAM1 genes and the protein SMAD2 might be key factors in the mir-155 regulated immune activities.

Regeneration and Recycling of Waste Thermosetting Plastics based on Mechanical Thermal Coupling Fields

Zhong-Wei Wu,Shaobo Pan,Guang-Fu Liu,Shou-Xu Song 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

In view of the present situation that the recovery of waste thermosetting plastics and products is difficult and the utilization rate islow, regeneration mechanism, regeneration methods and recycling process of waste thermosetting plastics under mechanical thermalcoupling fields are proposed. Regeneration powders of Thermosetting Phenolic plastic are obtained by mechanochemical activatedregeneration methods, the molecular structure, properties and crosslink density of phenol regeneration materials are analyzed. Analysis results show that network crosslinked molecular structure was destroyed, reactive groups produced and the crosslink densitydecreased. The activity of regeneration powders was reinforced and its plasticity was also improving, so the utilization rate wasimproved. Regeneration composite plastics were manufactured by hot press molding or extrusion compression molding. Themicrostructure of regeneration composite plastics was analyzed, and its mechanical strength was tested. Results showed that thetensile strength and bending strength of samples (weight ratio ≥ 50%) respectively exceed 15.88 MPa and 33.49 MPa. At last processparameters for regeneration effects were discussed, and these parameters were optimized. When particle size was 80 mesh (size ≤ 0.18mm), quality proportion was 50~70%, pressure was 10Mpa, heating temperature was 180~190oC, the optimal effects for regeneratedcomposite were achieved.

Numerical simulation of tip clearance impact on a pumpjet propulsor

Lin Lu,Guang Pan,Jing Wei,Yipeng Pan 대한조선학회 2016 International Journal of Naval Architecture and Oc Vol.8 No.3

Numerical simulation based on the Reynolds Averaged NaviereStokes (RANS) Computational Fluid Dynamics (CFD) method had been carried out with the commercial code ANSYS CFX. The structured grid and SST keu turbulence model had been adopted. The impact of noncondensable gas (NCG) on cavitation performance had been introduced into the Schnerr and Sauer cavitation model. The numerical investigation of cavitating flow of marine propeller E779A was carried out with different advance ratios and cavitation numbers to verify the numerical simulation method. Tip clearance effects on the performance of pumpjet propulsor had been investigated. Results showed that the structure and characteristics of the tip leakage vortex and the efficiency of the propulsor dropped more sharply with the increase of the tip clearance size. Furthermore, the numerical simulation of tip clearance cavitation of pumpjet propulsor had been presented with different rotational speed and tip clearance size. The mechanism of tip clearance cavitation causing a further loss of the efficiency had been studied. The influence of rotational speed and tip clearance size on tip clearance cavitation had been investigated.

Numerical simulation of tip clearance impact on a pumpjet propulsor

Lu, Lin,Pan, Guang,Wei, Jing,Pan, Yipeng The Society of Naval Architects of Korea 2016 International Journal of Naval Architecture and Oc Vol.8 No.3

Numerical simulation based on the Reynolds Averaged Naviere-Stokes (RANS) Computational Fluid Dynamics (CFD) method had been carried out with the commercial code ANSYS CFX. The structured grid and SST $k-{\omega}$ turbulence model had been adopted. The impact of non-condensable gas (NCG) on cavitation performance had been introduced into the Schnerr and Sauer cavitation model. The numerical investigation of cavitating flow of marine propeller E779A was carried out with different advance ratios and cavitation numbers to verify the numerical simulation method. Tip clearance effects on the performance of pumpjet propulsor had been investigated. Results showed that the structure and characteristics of the tip leakage vortex and the efficiency of the propulsor dropped more sharply with the increase of the tip clearance size. Furthermore, the numerical simulation of tip clearance cavitation of pumpjet propulsor had been presented with different rotational speed and tip clearance size. The mechanism of tip clearance cavitation causing a further loss of the efficiency had been studied. The influence of rotational speed and tip clearance size on tip clearance cavitation had been investigated.