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The advantages of fish such as high propulsion efficiency, strong maneuverability and low environmental disturbance have sparked extensive research on bionic robotic fish by both domestic and international scholars. The basic-level gait control method and closed-loop motion control method are currently two hot topics in research on robotic fish control. According to the propulsion mode classification method, this paper summarizes the prototype development and performance of various robotic fish, introduces the research progress of the propulsion mechanisms and hydrodynamics of robotic fish, focuses on two basic gait control ideas, namely the trajectory approximation method and central pattern generator （CPG）, and summarizes the typical closed-loop motion control method. The CPG method has stronger flexibility, stability and operability, and it is easy to introduce feedback items and achieve closed-loop control, for which it plays a leading role in the basic gait control of robotic fish; while the improved learning-based control method and hybrid control method combining multiple methods based on the significant characteristics of robotic fish have broader development prospects, which is in line with the development direction of intelligent biomimetic robotic fish. Establishing a reasonable gait control system and an accurate and efficient closed-loop motion control system based on working conditions and motion requirements is the key to improving the overall performance of robotic fish.

The double-floor storage tank can overcome the disadvantages of severe corrosion and strong leakage concealment of the traditional single-floor storage tank, but its upper floor is at the risk of fatigue failure under cyclic loading. Therefore, an axisymmetric model was established based on the structure and load symmetry for the vertical double-floor storage tank with annular grille structure. Through finite element analysis on the fatigue life of storage tanks during long-term service, the distribution of safety factor and fatigue life of the tanks out of service was studied in detail under the conditions of different bottom supports, grille spacing and thickness-to-width ratios of grille. The results show that the tank wall bottom is the most vulnerable part. Under the same grille arrangement and loading, the support mode with the floor connected by angle steel has higher fatigue reliability. Besides, the grille spacing and the thickness-to-width ratio have significant impact on the overall fatigue reliability of storage tanks. With the decrease of grille spacing and the thickness-to-width ratio, the overall safety factor and fatigue life of storage tanks increase, and their fatigue reliability also increases. Generally, the research results could provide a theoretical basis and technical reference for the structural design and optimization of vertical double-floor storage tanks.

Effects of four plant growth-promoting rhizobacteria (PGPR), namely Pseudomonas sp. YT3, Bacillus subtilis DZ1, B. cereus L90 and B. fusiformis L13 on the biological characteristics of walnut (Juglans regia) rhizosphere soil under drought stress were investigated. Results showed that drought stress had little effect on available nutrients of walnut rhizosphere soil, but significantly decreased the activity of organic carbon by 18. 4% and increased the pH from 7. 34 to 7. 79. Under drought stress condition, the inoculation of Bacillus cereus L90 significantly increased high-labile organic carbon in walnut rhizosphere by 14. 5% relative to the un-inoculated control, and decreased the pH to 7. 41. Compared with the irrigated control, the total microbial populations, root exudates, microbial biomass carbon, and microbial biomass nitrogen in walnut rhizosphere soil were significantly decreased by 36. 0%, 20. 7%, 33. 5% and 30. 7%, respectively, because of drought stress. However, L90 inoculation decreased these deficits to 14. 1%, 10. 3%, 12. 1% and 12. 7%, respectively. Some terminal restriction fragments (T?RFs) disappeared under the drought condition and PGPR inoculation had great influence on T-RFs according to Terminal Restriction Fragment Length Polymorphism profiles. The Margalef index and the Shannon index of walnut rhizosphere soil significantly decreased, but the Simpson index increased relative to the irrigated control. Compared with the un-inoculated control, the Margalef index significantly increased from 0. 42 to 0. 99, as well as the Shannon index increased from 0. 52 to 0. 98. However, the Simpson index decreased from 0. 60 to 0. 39. Inoculating YT3, DZ1 and L13 had weaker effects on the biological characteristics of walnut rhizosphere soil compared to inoculating L90, suggesting L90 inoculation could interfere with the suppression of drought stress to the biological characteristics of walnut rhizosphere soil. [ABSTRACT FROM AUTHOR]

This paper proposed an adaptive similarity mapping algorithm for high-speed Ethernet based on the special nature of user behavior and characteristics of the flow quintuple. It fully considered the random distribution of the quintuple in this algorithm and designed an improved XOR-SHIFT algorithm for flows classification. This paper raised concepts of similar database and heterogeneous database and designed similarity comparison functions for this two databases. With this method, similar eigenvalues can be mapped to data files precisely and matching efficiency is improved. It carried out some simulation tests in the campus network and proved that this mapping algorithm has higher precision and applicability than other methods. It is appropriate to search similarity flows in large data networks. [ABSTRACT FROM AUTHOR]

In order to solve problem of frequent override trip in high-voltage distribution network of coal mine underground, the paper analyzed causes of override trip in underground high-voltage distribution network and problems of common solutions in application including electrical locking, centralized control of substation, digital substation and differential protection of optical fiber current. It introduced the superiority of GOOSE message transmission protocol based on IEC61850 standard for data exchange. On the basis, it proposed a preventing override trip scheme based on GOOSE, and described implementation process of the scheme taking an underground high-voltage power line as an example. In the scheme, lower switches only associated with their upper switches, the upper switches and the lower ones communicated longitudinally through GOOSE protocol, and switches with the same grade do not communicated to each other, so as to improve real-time and reliability performance of information transmission.

A new type of line selection method of single-phase grounding leakage fault of coal mine high-voltage grid uses fault diagnosis method of current harmonic, zero-sequence active power method and transient zero-sequence current mutual product sum method to set membership functions of fault measures and weight coefficient, uses fuzzy theory to fusion the above functions of the three methods to calculate fault measures of line under line selection method with multi criteria, so as to judge line of single-phase grounding leakage fault. The Matlab/Simulink simulation result validates correctness of the line selection method.

Purpose: To investigate the effect of growth factor receptor-bound 7 (Grb7) on oral squamous cell carcinoma growth and tumor xenografts., Methods: Cal27 and hNOK cells were cultivated, real-time PCR and Western blotting were used to detect the expression of Grb7 in hNOK and Cal27. Cal27 was transfected with Grb7 siRNA for 48 h, cell proliferation was assayed using MTT. Flow cytometry was used to determine the cell cycle and apoptosis. Western blot was used to evaluate the expression of caspase3, Bax, bcl-2, Cyclin D1, Rb, E2F1, ERK and FOXM1. Grb7 siRNA and negative control were designed and injected subcutaneously into the mice, tumor volume and weight were measured. Statistical analysis was performed using SPSS 11.0 software package., Results: Grb7 was highly expressed in Cal27 compared with hNOK. Depletion of Grb7 significantly inhibited cell proliferation, blocked G1/S phase transition, promoted cell apoptosis. Knockdown of Grb7 suppressed the expression of Cyclin D1 and Rb, upregulated E2F1 expression. Moreover, c-caspase 3 and Bax was also reduced after inhibition of Grb7. ERK/FOXM1 signaling pathway was also inhibited by Grb7. In addition, the volume and weight of tumor xenografts were reduced by siGrb7., Conclusions: Depletion of Grb7 inhibits cell proliferation, promotes apoptosis and reduces tumor xenografts through ERK/FOXM1 pathway.

A pot experiment including five treatments, i.e., CK (neither fertilizer nor super absorbent polymers), U (urea alone), S [super absorbent polymers (SAP) alone], SUM (SAP mixed with urea) and SUG (gel made of SAP and urea) was conducted to evaluate their effects on fine root morphological characteristics, fine root absorption area, fine root nitrogen metabolism and nitrogen use efficiency of Platycladus orientalis bareroot seedlings. Results showed that compared with U treatment, the SUG treatment significantly increased the biomass, length, specific root length, surface area and volume of fine root. The total absorption area and active absorption area of fine root were also increased remarkably under the SUG treatment. The specific root length in the SUG treatment was increased by 34.7%, 37.9%, 41.1% and 12.4% compared with the treatments of CK, U, S and SUM, respectively. Compared with the U treatment, the activities of nitrate reductase, glutamine synthase, glutamate synthase and glutamate dehydrogenase in fine root of the SUG treatment was improved by 41.2%, 76.6%, 30.7% and 125.8%, respectively, while the ratio of GS to GDH decreased. Not only the ground diameter and plant height, but also the dry matter accumulation of aboveground and underground parts was remarkably enhanced under the SUG treatment. The nitrogen use efficiency was 40.7% in the SUG treatment, being 118.8% and 44.5% higher than the U and SUM treatments, respectively. Gel made of SAP and urea was able to significantly increase the nitrogen use efficiency, promote the growth and enhance the ability of drought resistance by improving the morphological characteristics, enhancing the absorption area and key enzymes activities of nitrogen metabolism in the fine root of P. orientalis bareroot seedlings.

Objective: To investigate the method and efficacy of reconstruction of anterior mouth floor defects with depressor labii inferioris flap., Methods: Between March 2010 and August 2011, 4 patients with cancer in the anterior part of oral floor underwent tumour resection and simultaneous reconstruction with depressor labii inferioris flap. The patients were followed up for 2 - 18 months. The survival of the flaps, mobility of tongue and esthetic outcome of lip and mental region were evaluated., Results: All the flaps survived completely, tongues moved well, and functional and esthetic results were good., Conclusions: The depressor labii inferioris flaps are suitable for repairing defects of anterior oral floor.

Objective: To measure the diameter of T4 pedicle-rib compomers in normal human spines and discuss the importance of related dates., Methods: T4 computerized tomography (CT) images,including two-dimensional,three-dimensional reconstruction, of 12 random adult patients were harvested. There were 7 males and 5 females with a mean age of 23 years (ranged, 19 to 28 years). The patients were divided into groups by self control,which means the diameter of pedicle compared with that of pedicle-rib unit in the same side of each T4. The facility was GE light speed 16. Measurement of the body specimens from T3 to T5 . The parameter included the width of pedicle-rib unit compared with pedicle,the longitudinal diameter of pedicle-rib unit compared with pedicle, especially for the pedicle-rib overlap., Results: The relationship of T4 pedicle and rib were not on the same level but overlapping. The width of pedicle-rib unit was significantly larger than that of pedicle (P<0.05). The longitudinal diameters of pedicle-rib unit or pedicle were significantly larger than those of pedicle-rib overlap (P<0.05); while there was no significantly difference between the pedicle-rib unit and pedicle (P>0.05)., Conclusion: The overlapping relationship of T4 pedicle and rib is partly but not whole, which means the longitudinal diameter of T4 pedicle-rib overlap should not be considered as the same of unit or pedicle.

Objectives: To investigate the spatial structure of pedicle rib units in normal thoracic human spines and to compare the dimensions of the pedicle rib unit with corresponding dimensions., Methods: Thoracic spine specimens in four fresh adult cadaveric were used. Computerized tomographic (CT) images (including two-dimensional, three-dimensional reconstruction) of the thoracic spines were obtained. Measurement parameters include:the width, the height, the chord length and the sagittal angles of the pedicle rib unit compared with pedicle, especially for the pedicle-rib overlapping height., Results: The pedicle rib unit was not a simple two-dimensional structure but a three-dimensional structure. The shortest height of pedicle rib unit was (12.6 ± 0.8) mm (T(1)), while the longest was (16.9 ± 1.1) mm (T(11)). The shortest height of pedicle-rib overlap was (7.2 ± 0.3) mm (T(1)), while the longest was (11.8 ± 1.0) mm (T(10)). The height of pedicle rib unit and the height of pedicle were significantly larger than that of the pedicle-rib overlap (P < 0.05), while there was no significantly difference between the height of pedicle rib unit and the height of pedicle (P > 0.05)., Conclusions: The pedicle rib unit is a complicated spatial structure, and the longitudinal height of pedicle-rib overlap should be taken as the real height of the unit.

To elucidate the potential influence of humic acidfertilizer on groundwater and soil quality in clay soil (CS) and sandy soil (SS), nitrate nitrogen leaching and residue of different fertilizers in field soil were studied using a self-made leaching field device. Nitrate nitrogen concentration in leaching water of fertilizer treatments was 28.1%-222.2% higher than that of non-nitrogen treatment in different times, but humic acid fertilizer could prevent nitrate nitrogen leaching both in CS and SS, especially in CS. Nitrate nitrogen concentration of leaching water in CS was 41.2%-59.1% less than that in SS and the inhibiting effect in CS was greater than that in SS. Nitrate nitrogen could be accumulated in soil profile by fertilizer application. The residue of nitrate nitrogen retained in 0-40 cm soil layer of humic acid fertilizer treatment was 59.8% and 54.4% respectively, higher than that of urea and compound fertilizer treatments. Nitrate nitrogen amount of humic acid, urea and compound fertilizer treatments in SS was significantly less than that in CS, being 81.7%, 81.1% and 47.6% respectively. Compared with the conventional fertilizer, humic acid fertilizer treatment improved the contents of organic matter, available nitrogen, phosphorus, and potassium of upper layer soil as well as cation exchange capacity. Besides, total amount of water-soluble salts in humic acid fertilizer treatment was decreased by 24.8% and 22.5% in comparison to urea and compound fertilizer treatments in CS, respectively. In summary, the application of humic acid fertilizer could improve physical and chemical properties of upper layer soil and reduce the risk of potential pollution to groundwater.

Ac and Ds insertions among the genomic DNAs of hybrids of Ac x Ds lines were screened by PCR. The genomic DNAs, which were proved to harbour both Ac and Ds, were used as templates in TAIL-PCR to clone the Ds flanking sequences. The cloned specific fragments were sequenced, and the sequenced Ds flanking sequences were used as query sequences to perform on-line sequence comparing analysis against GenBank by employing BLAST program of NCBI. The information about the chromosome location of Ds-inserted genes, or genes immediately downstream of the inserted sites, and their functional innotations were achieved. Based on the analysis from the cloned 93 Ds-flanking sequences, it was found that 21 hybrid plants had Ds insertions in genic regions, whereas the remaining 72 samples's intergenic regions were inserted by Ds element. Moreover, among the 72 regions, 12 were inserted immediately upstream (within 3 kb) of specific genes. Also, the strategies to improve the performance in cloning the Ds flanking sequences and in screening the Ac/Ds lines were emphasized.

In order to elucidate the relationship between the structural features of leginsulin gene in legume plants and their phylogenetic significance, we have cloned the cDNA sequence of leginsulin gene from radicles of broad bean (Vicia faba) via RT-PCR techniques according to the leginsulin gene sequence we previously obtained from soybean (Glycine max). The cloned cDNA encoded for a precursor protein consisting of the signal peptide, mature leginsulin and an additional 45 amino acids of another polypeptide. A sequence search for homology comparison revealed the cloned leginsulin cDNA fragment shares 62.5% and 58.7% similarity to soybean and pea, respectively. The results also shown that leginsulin cDNA from broad bean presents 44.2% and 43.6% amino acid sequence homology with soybean and pea (Pisum sativum), respectively, and that there exists highly conserved cysteine sites among the leginsulin cDNAs, which may play a crucial role in maintaining the three-dimensional structure and the physiological functions of leginsulin.