• Korean Journal of Microbiology
• /
• v.44 no.3
• /
• pp.203-211
• /
• 2008

Rapid detection-method for Shiga toxin type 1 that was produced from Shiga toxin-producing Escherichia coli (STEC) was developed by two-step ultra-rapid real-time (URRT) PCR. The specific primers were deduced from 80 bp stable region of stx type 1 (stxl) gene among various informations of STEC strains. URRT PCR is a microchip-based real-time PCR using 6 ${\mu}l$ of reaction volume with extremely short denaturation step and annealing/extension step (1 sec, 3 sec, respectively) in each cycle of PCR. Using the stx1-specific URRT PCR, 35 cycled PCR were finished in time of 6 min and 38 see, also measured 7 min and 28 see including melting temperature (Tm) analysis. The detection-limit of stxl-specific URRT-PCR was estimated until 3 colony forming units / PCR with products with stable Tm at $81.42{\pm}0.34^{\circ}C$. In the applications to various STEC strains and contaminated genomic DNAs, stx1-specific URRT-PCR were tested and shown that it would be expected an useful method for the rapid detection of stx1-coded STEC strains.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.8
• /
• pp.5369-5377
• /
• 2014

Korean pagodas were constructed in the shape of a wood pagoda, brick pagoda, stone pagoda, etc. On the other hand, the currently remaining traditional pagodas are those having nonflammable materials, such as brick, stone, etc. Compared to the stone pagoda, there is data regarding brick pagodas, but there is little literature data on how to construct these pagodas. This appears to be because there are relatively few Korean brick pagodas currently remaining, they are locally restricted, the material limit is not overcome, pagoda's historical and regional problems have not been analyzed, and pagoda construction is centered on pagoda construction. Therefore, this study examined the local cultural characteristics on the construction of brick pagodas. As a result, cultural exchange between Korea and China was performed through the silk road and there was a marine route for cultural exchange. Such exchange was shared with the East Asia area as well, which can be found by comparing remains at related areas. Exchange with China can be mentioned as the selective exchange of local powers as well as blind learning. Second, brick pagoda were constructed in Korea because of the good quality soil easily. Uisang's Hwaeomjong was negotiated with the main power not agreeing with Buddhism, which was popularized and the local power. Third, brick pagoda construction was influenced by negotiation related between Balhae and Silla, in which the ethnic influence was locally affected and could be mentioned as being a culturally selective result transferred from China. As a result, brick pagodas can be oriented by forming a unitary state rather than a small country within China's influence range as well as cultural transfer through the silk road.

• Journal of the Korean Geotechnical Society
• /
• v.33 no.7
• /
• pp.5-16
• /
• 2017

Soil nailing is the most general method to reinforce the slope by taking pullout and shear resistance force of the nail for stabilizing the slope. Domestic soil nailing design method considers only pullout resistance and does not consider the shear resistance sufficiently. In case of nail, the effect of tensile stress is dominant, but it is desirable to design by considering shear stress as well as tensile stress in case of slope where circle failures occur. Recently, studies on the shear resistance effect of nails have been carried out in the geotechnical field. However, many researches on the shear reinforcement effect of soil nailing have not been conducted until now. Most of the studies are about increasing pullout resistance by improving material, shape and construction method of nail. Therefore, it is necessary to the study on shear resistance of soil nailing and development of new methods to increase the shear force. In this study, large shear test and limit equilibrium analysis have been performed for a new soil nailing method to increase the shear resistance by forming protrusions through pressurized grouting after installing a packer on the outside of deformed bar. The study results showed that shear resistance of protrusion type soil nailing increased compared to soil nailing and it is more effective when applied to the ground with large strength parameters.

• Korean Journal of Materials Research
• /
• v.6 no.8
• /
• pp.779-785
• /
• 1996

Thin $700^{\circ}C$films were formed through layer inversion of Co/Nb bilayer during rapid thermal annealing(RTA). The Nb interlayer seems to effectively prevent over-consumption of Si and to control the silicidation reaction by forming Co-Nb intermetallic compounds and removing the native oxide formed on Si substrate which interferes the uniform Co-Si interaction. The final layer structure of the Co/Nb bilayer after $700^{\circ}C$ RTA was found to be ${Nb}_{2}{O}_{3}$/${Co}_{2}$Si.CoSi/${NbCo}_{x}$/Nb(O, C)/${CoSi}_{2}$/ Si. The layer inversion and the formation of a stable CoSi, phase occurred above $700^{\circ}C$, and the Nb silicides were not found at any annealing temperature. These may be due to the formation of very stable Co-Nb intermetallic compounds and Nb oxides which limit the moving of Co and Si.

• Korean Journal of Microbiology
• /
• v.34 no.3
• /
• pp.154-161
• /
• 1998

To investigate whether the introduced genetic marker is useful to detect the survivalship and activity of the natural bacteria under the stressed conditions, one Gram-negative isolate, KP964 was transformed to the luminous phenotype by transferring luxAB gene. Under the starvation-stress this luminous bacterial culturability (determined by colony-forming-units [CFU] on agar plate) decreased rapidly below the detection limit by 37 days, while its total cell number (determined by AODC) remained almost the same as its initial inocular size. At that time period, the viable cell number was estimated to be 1400 times higher than its CFU number. The bioiuminescence (determined by relative light units [RLU]) produced under the same condition was also monitored and found to decrease more rapidly than the culturability by 5-fold. Under the other stresses, e.g., osmotic shocks, acid shock, and exposure to toxic chemicals, this bacterial strain did not show the reliable correlation between CFU and RLU. These results might not suggest the direct estimation of bioiuminescence from the stressed bacteria be an index of both the survivalship and its activity. However, when the stressed bacterial cells were incubated under the favorable condition by relieving from the existing stress, the potential bioiuminescence (the lag periods before the increase of bioiuminescence, the increase rates of bioiuminescence, and the maximal levels of bioiuminescence) was shown to be highly dependent upon the strengths of the stresses exposed to the bacterial cells. Therefore, analysis of the potential bioiuminescence from the stressed bacteria revealed good relationships with survival as well as activity.

• Pediatric Infection and Vaccine
• /
• v.22 no.2
• /
• pp.106-112
• /
• 2015

Purpose: The long-term administration of antibiotics interferes with bacterial culture in the middle ear fluids (MEFs) of young children with otitis media with effusion (OME). The purpose of this study is to determine whether molecular diagnostics can be used for rapid and direct detection of the bacterial pathogen in culture-negative MEFs. Methods: The specificity and sensitivity of both polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) to the lytA gene of Streptococcus pneumoniae were comparatively tested and then applied for pneumococcal detection in the clinical MEFs. Results: The detection limit of the PCR assay was approximately $10^4$ colony forming units (CFU), whereas that of LAMP was less than 10 CFU for the detection of S. pneumoniae. Both PCR and LAMP did not amplify nucleic acid at over $10^6$ CFU of H. influenzae or M. catarrhalis, both of which were irrelevant bacterial species. Of 22 culture-negative MEFs from children with OME, LAMP positivity was found in twelve MEFs (54.5%, 12/22), only three of which were PCR-positive (25%, 3/12). Our results showed that the ability of LAMP to detect pneumococcal DNA is over four times higher than that of PCR (P<0.01). Conclusions: As a high-resolution tool able to detect nucleic acid levels equivalent to <10 CFU of S. pneumoniae in MEFs without any cross-reaction with other pathogens, lytA -specific LAMP may be applied for diagnosing pneumococcus infection in OME as well as evaluating the impact of a pneumococcal conjugate vaccine against OME.

• Archives of design research
• /
• v.19 no.5 s.67
• /
• pp.119-128
• /
• 2006

The scale of visual expression has expanded from freeze frame to motion picture as media have developed. Moving pictures such as animation, movies, TV CM and GUI become formative elements whose movement is necessary compared to freeze frame as apparent movement phenomenon and unit structure such as short and scene appear. Therefore, of formative elements such as a shape, color, space, size and movement, movement is importantly distinguished in the moving image. The expression and form of image as a relationship between the signified and signifier explained by Saussure are accepted as a sign by mutual complement even though they limit the content. This makes it possible to infer that the formal feature of movement participates in the message content. To verify this, the result of moving picture visual perception experiment based on the gestalt grouping principle result shows that 70-80 percent of subjects think that 'movement' is the important grouping clue in perception. Movement affects the maintenance of the context of message content in the communication process when the meaning structure of moving picture is analyzed based on the structural feature. The identity can be maintained with if there is a movement with similar directive point even if the color and shape of people, things and background are changed. Second, the clarity of the content is elevated by a distinguished object as a figure by movement. Third, it acts as a knowledge representation which can predict similar movement process of next information processing. Forth, movement gives the content consistency even though more than two scenes have fast switch and complicated editing structure like cross-cutting. Movement becomes a clue which can make grouping information input by visual perception reaction. Also, it gives the order to the visual expression which can be used improperly by formation of structural frame of image message and has the effectiveness which elevates the clarity of signification. Moving picture has discourse with several mixed unit structures because it fundamentally contains time and the common and distinguished expression is needed by media-mix circumstances. Therefore, by the application of gestalt grouping principle to moving picture field, movement becomes the more distinguished than other formative elements and affects the formation of meaning structure. This study propose a viewpoint that develops structural formative beauty and new image expression in the media image field.

• Journal of Wetlands Research
• /
• v.22 no.3
• /
• pp.194-199
• /
• 2020

Unlike in the past, the world is facing water shortages due to climate change and difficulties in simultaneously managing the risks of flooding. The Four Major Rivers project was carried out with the aim of realizing a powerful nation of water by managing water resources and fostering the water industry, and the construction period was relatively short compared to the unprecedented scale. Therefore, the prediction and analysis of how the river environment changes after the Four Major Rivers Project is insufficient. Currently, part of the construction section of the Four Major Rivers Project is caused by repeated erosion and sedimentation due to the effects of sandification caused by large dredging and flood-time reservoirs, and the head erosion of the tributaries occurs. In order to solve these problems, the riverbed maintenance work was installed, but it resulted in erosion of both sides of the river and the development of new approaches and techniques to keep the river bed stable, such as erosion and excessive sedimentation, is required. The water agent plays a role of securing a certain depth of water for the main stream by concentrating the flow so much in the center and preventing levee erosion by controlling the flow direction and flow velocity. In addition, Groyne products provide various ecological environments by forming a natural form of riverbeds by inducing local erosion and deposition in addition to the protection functions of the river bank and embankment. Therefore, after reviewing the method of determining the shape of the Groyne structure currently in use by utilizing the mobile limit flow rate and marginal reflux force, a new Critical Movement Velocity(${\bar{U}}_d$) and a new resistance coefficient formula considering the mathematical factors applicable to the actual domestic stream were developed and the measures applicable to Groyne installation were proposed.

• Analytical Science and Technology
• /
• v.25 no.3
• /
• pp.171-177
• /
• 2012

A determination method of aromatic amino acids such as trytophan (Trp), tyrosine (Tyr), and phenylalanine (Phe) using luminol-$H_2O_2$-Cu(II) system has been presented. In the presence of an aromatic amino acid, the enhanced chemiluminescence (CL) intensity of luminol-$H_2O_2$-Cu(II) system was obtained by forming a complex between Cu(II) and the amino acid. Based on the above phenomenon, a sensitive and fast determination of three aromatic amino acids was performed using the CL method in batch-type detection system. To optimize determination conditions, the kinetic influence of an aromatic amino acid on the luminol-$H_2O_2$-Cu(II) system and the effects of $H_2O_2$ and Cu(II) concentration, pH, and buffers were investigated. Under the optimized conditions, the calibration curve was linear over the range from $1.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Trp, $1.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Try, and $2.0{\times}10^{-6}$ to $2.0{\times}10^{-5}\;M$ for Phe, respectively. In this range, reproducibility (RSD, n = 4) of Trp, Try, and Phe were 3.21%, 2.64%, and 2.48%, respectively. The limit of detection ($3{\sigma}/s$) was calculated to be $6.8{\times}10^{-7}\;M$ for Trp, $5.7{\times}10^{-7}\;M$ for Try, and $9.6{\times}10^{-7}\;M$ for Phe.

• Journal of Korean Society of Forest Science
• /
• v.1 no.1
• /
• pp.22-29
• /
• 1962

(1) The objects of this study are to observe the possibility of regenerating a young merchantable pitch pine stand by sprouts and to compare the growth trend of sprouts with that of seedlings of same age grown under the almost same circumstances. (2) A plot of 20 year old pitch pine plantation, i.e. 200 trees on 0.1 ha of average D.B.H. 14 cm was clearcut at 20 cm above ground in April, 1945. By the late spring of that year sixty per cent of the cut stumps had sprouted. (3) Fourty to eighty sprouts were found on each stump (maximum:412 sprouts) at the first, but many of them had gradually died out leaving only four to five sprouts per stump by the time of three years after cutting. At that time only one vigorous sprout was left per stump by eliminating the weaker ones. (4) The sprouts, as they grew, started to cover the old stumps with new tissues developed from lower part of sprouts;consequently forming new root systems from the base of new tissues, and they appeared to be seedlings. When the age of sprouts was thirteen years old, the old stumps were completely decayed away and the reproduced stand from sprouts was averaged at 9.7 cm in D.B.H. and at 5.5m in height. (5) When the age of sprouts was thirteen years old, the sprouts exceeded the seedlings in both of total present growth and mean annual increment in height, volume, D.B.H. and basal area, but the seedlings began to exceed the sprouts in current annual increment of height, volume, D.B.H. and basal area at about ten years of age. The rates of increment of the seedling in height, volume, ect. were larger than those of sprouts except when they were one to four years old. From above facts, the following may be concluded: (1) In regenerating a pitch pine stand by sprouts, the lower the stump height, the better the result. (2) If no light limit exists, regenerating a pitch pine stand by sprouts is well possible even at the age of 20 year. (3) Pitch pine reproduction started from sprouts exceeds the seedlings of same age in growth under the almost same circumstances until they get ten years of age.