• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.168-176
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• 2014

The morphology of filamentous fungi closely correlates with the productivity in submerged culture. Using itaconic acid (IA) production by Aspergillus terreus as a research model, the quantitative relationship between the growth form of A. terreus and IA production was investigated. IA fermentation was scaled up from shake flasks to a 7 L stirred tank bioreactor based on the quantitative relationship. Our results demonstrated the following: (1) Three morphologies of A. terreus were formed by changing the inoculum level and shape of the flask. (2) Investigation of the effects of the three morphologies on broth rheology and IA production revealed the higher yield of IA on dry cell weight (DCW, IA/DCW) and yield of glucose on DCW (consumed glucose/DCW) were achieved during clump growth of A. terreus. (3) By varying the $KH_2PO_4$ concentration and culture temperature, the relationships between clump diameter and IA production were established, demonstrating that the yield of IA on DCW ($R^2$ = 0.9809) and yield of glucose on DCW ($R^2$ = 0.9421) were closely correlated with clump diameter. The optimum clump diameter range for higher IA production was 0.40-0.50 mm. (4) When the clump diameter was controlled at 0.45 mm by manipulating the mechanical stress in a 7 L fermentor, the yield of IA on DCW and yield of glucose on DCW were increased by 25.1% and 16.3%, respectively. The results presented in this study provide a potential approach for further enhancement of metabolite production by filamentous fungi.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.1
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• pp.67-76
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• 2007

The conclusion of free Trade Agreement between South Korea and USA can become a serious threat to the Korean agriculture. On the strategic scheme the foodstuffs is the basis for protection of the state sovereignty. The Amur oblast of Russian Federation is region, which can supply South Korea cheap and good qualitative feeds. It means South Korea should create agricultural cooperation with the Amur oblast of Russian Federation with the purpose to begin organic agriculture in this area and it will help South Korea to counteract a quantitative attack on Korea from the side of american agricultural production. In the Amur oblast there are following fodder crops; Alfalfa, Smooth brome grass (gromus adonis L.), Siberian couch grass, Sudan pass, Colza rape (Brassica napus) and Amaranth (Avfranthus). In the same area also exist oatmeal, wheat, corn and barley, which is possible to use for feeds. All these above written cultures are cultivated organically, therefore it is possible to use them as organic forages in South Korea. It is very important to know system of crop rotation in the Amur oblast. There is a scheme of crop rotation, which is connected with increase and preservation of fertility of soil, maintenance of growth of productivity of agricultural cultures and reception of high-quality production. It is necessary to begin organic agriculture in a southern part of Amur oblast, where, in 2001 year, 97% of all sowing areas was concentrated. The acidity degree of soil in this part is not high ($ph5.1{\sim}5.5$), therefore does not require liming.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.139-160
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• 2017

The bearing mechanism of tunnel-type anchorage (TTA) for suspension bridges is studied. Model tests are conducted using different shapes of plug bodies, which are circular column shape and circular truncated cone shape. The results show that the plug body of the latter shape possesses much larger bearing capacity, namely 4.48 times at elastic deformation stage and 4.54 times at failure stage compared to the former shape. Numerical simulation is then conducted to understand the mechanical and structural responses of plug body and surrounding rock mass. The mechanical parameters of the surrounding rock mass are firstly back-analyzed based on the monitoring data. The calculation laws of deformation and equivalent plastic strain show that the numerical simulation results are rational and provide subsequent mechanism analysis with an established basis. Afterwards, the bearing mechanism of TTA is studied. It is concluded that the plug body of circular truncated cone shape is able to take advantage of the material strength of the surrounding rock mass, which greatly enhances its bearing capacity. The ultimate bearing capacity of TTA, therefore, is concluded to be determined by the material strength of surrounding rock mass. Finally, recommendations for TTA design are proposed and discussed.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.53-69
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• 2017

Rock burst may cause serious casualties and property losses, and how to conduct effective monitoring and warning is the key to avoid this disaster. In this paper, we reviewed both the rock burst mechanism and the principle of using electromagnetic radiation (EMR) from coal rock to monitor and forewarn rock burst, and systematically studied EMR monitored data of 4 rock bursts of Qianqiu Coal Mine, Yima Coal Group, Co. Ltd. Results show that (1) Before rock burst occurrence, there is a breeding process for stress accumulation and energy concentration inside the coal rock mass subject to external stresses, which causes it to crack, emitting a large amount of EMR; when the EMR level reaches a certain intensity, which reveals that deformation and fracture inside the coal rock mass have become serious, rock burst may occur anytime and it's necessary to implement an early warning. (2) Monitored EMR indicators such as its intensity and pulses amount are well and positively correlated before rock bursts occurs, generally showing a rising trend for more than 5 continuous days either slowly or dramatically, and the disaster bursts generally occurs at the lower level within 48 h after reaching its peak intensity. (3) The rank of EMR signals sensitive to rock burst in a descending order is maximum EMR intensity > rate of change in EMR intensity > maximum amount of EMR pulses > rate of change in the amount of EMR pulses.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2135-2145
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• 2015

VP7, an outer capsid protein of grass carp reovirus (GCRV), was expressed and displayed on the surface of Saccharomyces cerevisiae for developing an efficient vaccine against hemorrhagic disease of grass carp. The result of flow cytometry analysis indicated that protein VP7 could be displayed on the surface of yeast cells after inducing with galactose. The expression of VP7 was confirmed by western blot analysis and further visualized with confocal microscopy. The specific antibodies against VP7 generated from mice were detectable from all immune groups except the control group, which was immunized with untransformed yeast cells. The displaying VP7 on glycosylation-deficient strain EBYΔMnn9 was detected to induce a relatively low level of specific antibody amongst the three strains. However, the antiserum of EBYΔM9-VP7 showed relative high capacity to neutralize GCRV. Further neutralization testing assays indicated that the neutralizing ability of antiserum of the EBYΔM9-VP7 group appeared concentration dependent, and could be up to 66.7% when the antiserum was diluted to 1:50. This result indicates that appropriate gene modification of glycosylation in a yeast strain has essential effect on the immunogenicity of a yeast-based vaccine.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.978-987
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• 2015

Aluminum (Al) toxicity is one of the greatest limitations to agriculture in acid soils, particularly in tropical regions. Arbuscular mycorrhizal fungi (AMF) can supply plants with nutrients and give protection against Al toxicity. The aim of this work was to evaluate the effects of soil liming (i.e., reducing Al saturation) on the AMF community composition and structure in the roots of maize lines contrasting for Al tolerance. To this end, we constructed four 18S rDNA cloning libraries from L3 (Al tolerant) and L22 (Al sensitive) maize lines grown in limed and non-limed soils. A total of 790 clones were sequenced, 69% belonging to the Glomeromycota phylum. The remaining sequences were from Ascomycota, which were more prominent in the limed soil, mainly in the L3 line. The most abundant AM fungal clones were related to the family Glomeraceae represented by the genera uncultured Glomus followed by Rhizophagus and Funneliformis. However, the most abundant operational taxonomic units with 27% of the Glomeromycota clones was affiliated to genus Racocetra. This genus was present in all the four libraries, but it was predominant in the non-limed soils, suggesting that Racocetra is tolerant to Al toxicity. Similarly, Acaulospora and Rhizophagus were also present mostly in both lines in non-limed soils. The community richness of AMF in the non-limed soils was higher than the limed soil for both lines. The results suggest that the soil Al saturation was the parameter that mostly influences the AMF species composition in the soils in this study.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2116-2124
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• 2015

To understand the effects of physicochemical factors on nitrite transformation by microalgae, a lipid-rich Chlorella with high nitrite tolerance was cultured with 8 mmol/l sodium nitrite as sole nitrogen source under different conditions. The results showed that nitrite transformation was mainly dependent on the metabolic activities of algal cells rather than oxidation of nitrite by dissolved oxygen. Light intensity, temperature, pH, NaHCO₃ concentrations, and initial cell densities had significant effects on the rate of nitrite transformation. Single-factor experiments revealed that the optimum conditions for nitrite transformation were light intensity: 300 μmol/m²/s; temperature: 30℃ pH: 7-8; NaHCO₃ concentration: 2.0 g/l; and initial cell density: 0.15 g/l; and the highest nitrite transformation rate of 1.36 mmol/l/d was achieved. There was a positive correlation between nitrite transformation rate and the growth of Chlorella. The relationship between nitrite transformation rate (mg/l/d) and biomass productivity (g/l/d) could be described by the regression equation y = 61.3x (R² = 0.9665), meaning that 61.3 mg N element was assimilated by 1.0 g dry biomass on average, which indicated that the nitrite transformation is a process of consuming nitrite as nitrogen source by Chlorella. The results demonstrated that the Chlorella suspension was able to assimilate nitrite efficiently, which implied the feasibility of using flue gas for mass production of Chlorella without preliminary removal of NO_X.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.2
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• pp.157-168
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• 2008

Tightening of the screws in implant restorations should be accurate and precise. If applied torque is too low, screw loosening would be occurred. With too high torque, the screw fracture might take place. Various torque generating devices are developed and employed to apply a proper torque. The purpose of this investigation was to determine and compare the accuracy of the torque controllers. In this study, 4 types of torque controllers were used; electronic torque controller, torque limiting device, torque indicating device and contra angle torque driver. Digital torque gauge was employed to measure the de-torque value. Thirty cycles of tightening and loosening were done with each torque controller. All implant torque controllers have shown slight errors and deviations. The torque liming device exhibited the most accurate data. No significant difference was found among the mean de-torque values of the electronic torque controller, torque indicating device and contra angle torque driver. In the limitation of this study, it would be recommended that the implant torque controllers should be checked whether uniformed and precise torque can be generated and a measuring error should be corrected.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2160-2179
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• 2015

In many Radio Frequency Identification (RFID) applications, the reader recognizes the tags within its scope repeatedly. For these applications, some algorithms such as the adaptive query splitting algorithm (AQS) and the novel semi-blocking AQS (SBA) were proposed. In these algorithms, a staying tag retransmits its ID to the reader to be identified, even though the ID of the tag is stored in the reader's memory. When the length of tag ID is long, the reader consumes a long time to identify the staying tags. To overcome this deficiency, we propose a slot allocated blocking anti-collision algorithm (SABA). In SABA, the reader assigns a unique slot to each tag in its range by using a slot allocation mechanism. Based on the allocated slot, each staying tag only replies a short data to the reader in the identification process. As a result, the amount of data transmitted by the staying tags is reduced greatly and the identification rate of the reader is improved effectively. The identification rate and the data amount transmitted by tags of SABA are analyzed theoretically and verified by various simulations. The simulation and analysis results show that the performance of SABA is superior to the existing algorithms significantly.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.9
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• pp.1326-1333
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• 2002

Studies were conducted with nine barrows, average initial body weight $44.5{\pm}2.1kg$, fitted with a T-cannula at the distal ileum, to determine the apparent ileal (and true) digestibility (AID and TID) of CP and AA in different cultivars of rapeseed meals and soybean meal. The barrows were fed either a casein diet or one of eight corn starch-based semipurified diets, formulated to contain 17.0% CP (DM basis) with one of seven different cultivars of rapeseed meal or soybean meal as the sole source of dietary protein, according to a six-period, nine-treatment, incomplete Latin Square. Chromic oxide (0.5%) was used as a digestibility marker. The pigs were fed of 4% of body weight twice daily, at 08:00 and 20:00 h. Ileal digesta were collected at 2 h intervals daily from 5 d to 7 d. The AID or TID values of CP and most AA (Cysteine excluded) were significantly lower in the rapeseed meals than in soybean meal (p<0.05). There were significant differences in the AID or TID values of CP and AA among the seven different cultivars rapeseed meals (p<0.05); the seven rapeseed meals were arranged according to the size of the AA digestibility values of the rapeseed meals from the greatest to the least, as Zayou 59, Youyan 7, Ganyou 16, Qingyou 2, Huaza 3, Ningza 1 and Lianglou 586; differences in CP, AA, NDF and ADF contents in the rapeseed meals were mainly responsible for the variation in the AID or TID values of AA among rapeseed meals. The AID value of CP can be used as an index of the AID or TID values of most AA in rapeseed meals. However, the AID value of CP was less appropriate as a direct indicator of the AID or TID values for cysteine, methionine, tryptophan, phenylalanine and proline.