• Food Science and Biotechnology
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• v.16 no.2
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• pp.255-259
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• 2007

The effects of temperature heating-up rate and pressure building-up phase on the inactivation of Listeria innocua ATCC 33090 were evaluated in buffered peptone water. The number of L. innocua was reduced by 5.57 and 6.52 log CFU/mL during the nonisothermal treatment (the come-up time followed by isothermal process) and the isothermal treatment, respectively, at $60^{\circ}C$. When compared to the isothermal treatment (0.76$33.2^{\circ}C/min$ of temperature heating-rate. The effect of the combined high pressure and thermal processing on the inactivation of L. innocua increased with increasing pressure and temperature. At all temperature levels from 40 to $60^{\circ}C$ under 700 MPa, L. innocua was not detected by enrichment culture (>7 log reduction).

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.141-146
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• 2001

Protoplasts were isolated from cotyledons, hypocotyls, and mesophyll tissues of three species of Capsicum species (C. anuumm, C. bacatuum, and C. chacoense). Combination of Cellulysin (1%) and Macero-zyme (0.25%) in 0.65 M sorbitol was found to be the most effective for the digestion of cell wall, regardless of the Capsicum species. Antioxidant MES (2-［N-Morpholino］ethanesulfonic acid) in the enzyme solution helped protoplasts overcome browning. After 5 days of initial culture, Cell division occurred in modified K8p medium containing 1~5 mg/L zeatin, 0.5 mg/L IAA, 0.1~0.5 mg/L TDZ, and 1 mg/L 2,4-D under continuous dark condition at $25^{\circ}C$. Semi-solid agarose culture method was more effective than liquid culture, and it also protected the cells from browning caused by polyphenolic compound released during protoplast culture. A total of 4000 calli were obtained from protoplast culture of different capsicum species. All of these calli were transferred to the 100 combinations of regeneration media using various plant growth regulators; TDZ, IAA, 2ip, BAP, NAA, and zeatin. These calli derived from protoplast of three species of capsicum were, however, not differentiated into shoots.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1001-1008
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• 1996

Staphylococcal food poisoning is the major cause of bacterial food poisoning occurring in this country. Therefore government regulates commercial foods through Official Dictionary of Food that there should be free of enterotoxigenic Staphylococcus aureus in Korean rice cakes, bread, and a box lunch. Since at least 5 days are required to identify the S. aureus by the official method in the Dictionary it is difficult to prevent the food poisoning and the investigation of the outbreaks. In this report an improved determination method of the S. aureus has been developed using polymerase chain reaction (PCR) technique. Sense and antisense primers for specific amplification of genes encoding staphylococcal enterotoxins were designed and synthesized for the PCR. Rapid chromosomal DNA isolation method was also developed from S. aureus using lysostaphin. The PCR condition was developed as follows. Reaction solution $(50\;{\mu}l)$ consisted of target DNA $2\;{\mu}l$ (about 20ng), 10X buffer $5\;{\mu}l$, primer 100pmole, dNTP (10 mM) $4\;{\mu}l$ and Taq DNA polymerase 2.5 unit in a thin-wall tube. Operation condition of the PCR was 5 min pre-denaturation at $94^{\circ}C$, 15 sec denaturation at $94^{\circ}C$, 15 sec annealing at $50^{\circ}C$, 20 sec extension at $72^{\circ}C$, and 5 min post-extension at $72^{\circ}C$, and 30 cycles of denaturation-annealing- extension. Using the PCR with Perkin Elmer GeneAmp PCR system 2400, types of enterotoxigenic S. aureus could be identified from Ddok or bread in a day.

• Journal of the Korean Magnetic Resonance Society
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• v.4 no.2
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• pp.125-132
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• 2000

The detailed $^1$H and $^{13}$ C NMR assignments of a novel sucrose isovaleryl ester isolated from the seed of Euphorbia Lathyris L., were achieved by one-and two-dimensional techniques. The new sucrose ester was characterized as an $\alpha$-D-glucopyranoside, 3,4,6-tris-O-(3-methyl-1-oxobutyl)-$\beta$-D-fructofuranosyl, 2,6-bis(3-methylbutanoate); sucrose 4,7,8,11,12-pentaisovalerate by MS and NMR experiments.

• Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.180-194
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• 2024

Mass mortalities of mud crab Scylla spp. larvae due to pathogenic Vibrio spp. outbreaks have frequently occurred in hatcheries. To overcome this problem, probiotics containing Bacillus subtilis bacteria are applied to inhibit pathogenic ones. We tested different doses of probiotic-containing B. subtilis (10⁸ CFU/g) on the Scylla tranquebarica larvae and investigated the microbiota population, including Vibrio. Water quality, larvae development, and crablet production were also monitored. The recently hatched larvae were grown in twelve conical fiber tanks filled with 200 L sterile seawater, with a salinity of 30 ppt at a stocking density of 80 ind/L. Four different doses of probiotics were applied in the larvae rearing, namely, A = 2.5 mg/L, B = 5 mg/L, C = 7.5 mg/L, and D = 0 mg/L, with three replicates. Next-generation sequencing analysis was used to obtain the abundance of microbes in the whole body of megalopa and the water media for larvae rearing after applying probiotics. Sixteen Raw Deoxyribonucleic Acid samples (eight from a whole body of megalopa extraction from four treatments of probiotics defined as A, B, C, D, and eight from water media extraction from four treatments of probiotic defined as E, F, G, H) were prepared. Then, they were sent to the Genetics Science Laboratory for NGS analysis. Ammonia, nitrite, total organic matter (TOM), larvae, and crablet production were monitored. Based on the Next-generation sequencing analysis data, the Vibrio spp. decreased significantly (p < 0.05) than control test (D) in megalopa-applied probiotics at the doses of 2.5 mg/L (A) and 7.5 mg/L (C) and in the water media for megalopa rearing treated with probiotics at the dosage of 5.0 mg/L (F). Ammonia in the zoea stage in B treatment and TOM in the zoea and megalopa stage in B and C treatments were decreased significantly (p < 0.05). It impacts the higher number of zoea survival in treatments B and C. Finally, it results in a significantly high crablet production in treatments B and C. Therefore, the dosage of 5 mg/L to 7.5 mg/L improves crablet S. tranquebarica production significantly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.76-90
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• 1993

To clarify the relations between photoperiodism and x-organ of eyestalks to the control of gonadal maturation in a freshwater prawn, Macrobrachium nipponense, the present investigation was performed with following examinations: 1) the influence of water temperature and daylength on the control of gonadal maturation, 2) the effect of eyestalk ablation on the gonadal maturation, 3) the seasonal variation of histology of MEX-organ (medulla externa X-organ) in the eyestalk. In previtellogenesis period (December${\sim}$March) and vitellogenesis period (April${\sim}$May), gonadal maturation was considerablely influnced by water temperature. In these periods, GSI increased and gonads were matured with water temperature rising without regard to photoperiod conditions (12L/12D and 15L/9D). In spawning period (June${\sim}$August), however, gonadal maturation was influenced by photoperiod condition. While high value of GSI was kept at long photoperiod regime (15L/9D), GSI was decreased at short photoperiod regime (12L/12D). In resting period (September${\sim}$November), no rematuration was occurred at all the experimental regimes combinated with water temperatures ($16^{\circ}C,\;22^{\circ}C,\;28^{\circ}C$) and photoperiod (12L/12D, 15L/9D). Effect of X-organ which inhibite the gonadal maturation was stronger in resting period than that in previtellogenesis and ealy spawning periods by observations on the effectiveness of eyestalk ablation on the gonadal maturation. In MEX-organ of eyestalk, the number of neurosecretory cells of which size was over $20{\mu}m$ in diameter varied according to the reproductive cycle. The number of cells increased $77{\pm}12$ in resting period, and decreased $55{\pm}7$ in vitellogenesis period. Volume of Bellonci's organ, however, increased in vitellogenesis period in comparison with that in resting period.

• Magazine of the Korean Society of Agricultural Engineers
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• v.20 no.1
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• pp.4592-4598
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• 1978

The purpose of this research is to find out mathemetically an economical intake water depth in the design of head works through the derivation of some formulas. For the performance of the purpose the following formulas were found out for the design intake water depth in each flow type of intake sluice, such as overflow type and orifice type. (1) The conditional equations of !he economical intake water depth in .case that weir body is placed on permeable soil layer ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } { Cp}_{3 }L(0.67 SQRT { q} -0.61) { ( { d}_{0 }+ { h}_{1 }+ { h}_{0 } )}^{- { 1} over {2 } }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { dcp}_{3 }L+ { nkp}_{5 }+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ] =0}}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }+ { 1} over {2 } C { p}_{3 }L(0.67 SQRT { q} -0.61)}}}} {{{{ { ({d }_{0 }+ { h}_{1 }+ { h}_{0 } )}^{ - { 1} over {2 } }- { { 3Q}_{1 } { p}_{ 6} { { h}_{1 } }^{- { 5} over {2 } } } over { { 2m}_{ 2}m' SQRT { 2gs} }+[ LEFT { b+ { 4C TIMES { 0.61}^{2 } } over {3(r-1) }+z( { d}_{0 }+ { h}_{0 } ) RIGHT } { p}_{1 }L }}}} {{{{+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 } L+dC { p}_{4 }L+(2 { z}_{0 }+m )(1-s) { L}_{d } { p}_{7 }]=0 }}}} where, z=outer slope of weir body (value of cotangent), h1=intake water depth (m), L=total length of weir (m), C=Bligh's creep ratio, q=flood discharge overflowing weir crest per unit length of weir (m3/sec/m), d0=average height to intake sill elevation in weir (m), h0=freeboard of weir (m), Q1=design irrigation requirements (m3/sec), m1=coefficient of head loss (0.9∼0.95) s=(h1-h2)/h1, h2=flow water depth outside intake sluice gate (m), b=width of weir crest (m), r=specific weight of weir materials, d=depth of cutting along seepage length under the weir (m), n=number of side contraction, k=coefficient of side contraction loss (0.02∼0.04), m2=coefficient of discharge (0.7∼0.9) m'=h0/h1, h0=open height of gate (m), p1 and p4=unit price of weir body and of excavation of weir site, respectively (won/㎥), p2 and p3=unit price of construction form and of revetment for protection of downstream riverbed, respectively (won/㎡), p5 and p6=average cost per unit width of intake sluice including cost of intake canal having the same one as width of the sluice in case of overflow type and orifice type respectively (won/m), zo : inner slope of section area in intake canal from its beginning point to its changing point to ordinary flow section, m: coefficient concerning the mean width of intak canal site,a : freeboard of intake canal. (2) The conditional equations of the economical intake water depth in case that weir body is built on the foundation of rock bed ; (a) in the overflow type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{5 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{1 }(1-s) SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L+ { nkp}_{5 }}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0 }}}} (b) in the orifice type of intake sluice, {{{{ { zp}_{1 } { Lh}_{1 }- { { { 3Q}_{1 } { p}_{6 } { h}_{1 } }^{- {5 } over {2 } } } over { { 2m}_{2 }m' SQRT { 2gs} }+[ LEFT { b+z( { d}_{0 }+ { h}_{0 } )RIGHT } { p}_{1 }L+(1+ SQRT { 1+ { z}^{2 } } ) { p}_{2 }L}}}} {{{{+( { 2z}_{0 }+m )(1-s) { L}_{d } { p}_{7 } ]=0}}}} The construction cost of weir cut-off and revetment on outside slope of leeve, and the damages suffered from inundation in upstream area were not included in the process of deriving the above conditional equations, but it is true that magnitude of intake water depth influences somewhat on the cost and damages. Therefore, in applying the above equations the fact that should not be over looked is that the design value of intake water depth to be adopted should not be more largely determined than the value of h1 satisfying the above formulas.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.749-754
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• 2000

PCR primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of the enzymes involved in the biosynthesis of deoxysugar. The PCR product (360 bp) was obtained from Thermus caldophilus GK24. Colony hybridization was carried out to the cosmid library constructed from T. caldophilus GK24 genomic DNA by the PCR product DNA fragment. We isolated a cosmid clone (pSMTC-1) that was subcloned to call pKCB series plasmid (BamHI fragments), partially sequenced and analyzed. pKCB80 (4.2 kb-BamHI DNA fragment) of them showed ORFs that was orfA, orfB, orfC and orfD. The orfABCD gene cluster is the deosysugar biosynthetic gene ; orfA (glucose-1-phosphate thymidylytransferase), orfB (dTDP-D-glucose 4,6-dehydratase), orfC (dTDP-4-keto-L-rhamnose reductase) and orfD (dTDP-4-keto-6-deoxy-D-glucose 3,5-epimerase). The gene cluster that was related in biosynthesis of dTDP-L-rhamnose was also identified by computer analysis, and we proposed that the biosynthetic pathway of deoxysugar analyzed from DNA sequencing of pKCB80 is from D-glucose-1-phosphate, dTDP-D-glucose, dTDP-4-keto-6-deoxy-D-glucose via dTDP-4-keto-L-rhamnose to dTDP-L-rhamnose.

• Journal of Sensor Science and Technology
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• v.7 no.2
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• pp.124-130
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• 1998

High-speed 3D vision systems are essential for autonomous robot or vehicle control applications. In our study, a stereo vision process has been developed. It consists of three steps : extraction of edges in right and left images, matching corresponding edges and calculation of the 3D map. This process is implemented in a VME 150/40 Imaging Technology vision system. It is a modular system composed by a display, an acquisition, a four Mbytes image frame memory, and three computational cards. Programmable accelerator computational modules are running at 40 MHz and are based on TMS320C31 DSP with a $64{\times}32$ bit instruction cache and two $1024{\times}32$ bit internal RAMs. Each is equipped with 512 Kbytes static RAM, 4 Mbytes image memory, 1 Mbytes flash EEPROM and a serial port. Data transfers and communications between modules are provided by three 8 bit global video bus, and three local configurable pipeline 8 bit video bus. The VME bus is dedicated to system management. Tasks between DSPs are distributed as follows: two DSPs are used to edges detection, one for the right image and the other for the left one. The last processor computes the matching process and the 3D calculation. With $512{\times}512$ pixels images, this sensor generates dense 3D maps at a rate of about 1 Hz depending of the scene complexity. Results can surely be improved by using a special suited multiprocessors cards.

• Journal of the Korean GEO-environmental Society
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• v.10 no.3
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• pp.37-45
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• 2009

The experimental study was carried out to evaluate the characteristics of the point load index and the uniaxial compressive strength of inherently anisotropic shale in the laboratory. In the testing program the effects of size and the shape on the point load index were investigated both in the axial and diametral direction. In general, the point load index of the shale was constant when the length/diameter (L/D) ratio of the specimen is greater than 1.0 in the diametral direction. The point load index in axial direction shows slight decrease as the L/D ratio is increased and the corner breakage was observed when L/D ratio is greater than unity. The minimum point load index was observed in the bedding angle of $\beta=15^{\circ}{\sim}30^{\circ}$ in the axial point load tests and of $\beta=30^{\circ}$ in the uniaxial compression tests. The relationship between the point load index and the uniaxial compressive strength was linear to ${\sigma}_c=25.0 I_{s(50)}$ for the specimen with the bedding plane angle, $\beta$ at the range of $0^{\circ}{\sim}90^{\circ}$. On the other hand, this relationship was appeared linear to ${\sigma}_c=14.4 I_{s(50)}$ when the bedding angle, $\beta$ is fixed to 90${^{\circ}}$ and this correlation is much different from ${\sigma}c=22 I_{s(50)}, which is generally applied to the rock specimen with no bedding plane in ISRM (1985). The anisotropic strength with different $\beta$ angle shows the shoulder type and this can be suitably modelled by the corrected Ramamurthy'(1993)s equation with the index value of 'n' equal to 3.0.