β-Ga2O3 has become the focus of considerable attention as an ultra-wide bandgap semiconductor following the successful development of bulk single crystals using the melt growth method. Accordingly, homoepitaxy studies, where the interface between the substrate and the epilayer is not problematic, have become mainstream and many results have been published. However, because the cost of homo-substrates is high, research is still mainly at the laboratory level and has not yet been scaled up to commercialization. To overcome this problem, many researchers are trying to grow high quality Ga2O3 epilayers on hetero-substrates. We used diluted SiH4 gas to control the doping concentration during the heteroepitaxial growth of β-Ga2O3 on c-plane sapphire using metal organic chemical vapor deposition (MOCVD). Despite the high level of defect density inside the grown β-Ga2O3 epilayer due to the aggregation of random rotated domains, the carrier concentration could be controlled from 1 × 1019 to 1 × 1016 cm-3 by diluting the SiH4 gas concentration. This study indicates that β-Ga2O3 hetero-epitaxy has similar potential to homo-epitaxy and is expected to accelerate the commercialization of β-Ga2O3 applications with the advantage of low substrate cost.
Olfactory receptors (OR) are primarily responsible for the detection of odorant molecules. We previously demonstrated that OR7D4, an OR for androstenone, is expressed in the vomeronasal organ and olfactory epithelium tissue of stallions. Recently, the expression of OR1I1 in the human testes was reported and the possible roles of OR1I1 in the testicular cells were suggested. The objectives of this study were 1) to explore the expression of OR7D4 and OR1I1 in stallion testes, and 2) to define the specific localization of OR7D4 and OR1I1 in the testicular tissues. Stallion testicular tissue samples were used for this study. Western blot was performed to confirm the cross-reactivity of OR7D4 and OR1I1 antibody with stallion testicular tissue samples. OR7D4 and OR1I1 gene expressions were investigated using reverse transcriptionpolymerase chain reaction (RT-PCR) in stallion testes. Immunofluorescence was performed to investigate the expression of OR7D4 and OR1I1 in stallion testicular tissues. The protein bands for OR7D4 and OR1I1 from the testes were observed at approximately 38 kDa and 43 kDa, respectively. The mRNA of OR7D4 and OR1I1 were detected in stallion testes. Immunolabeling of OR7D4 and OR1I1 in the cytoplasm of both spermatogonia and Leydig cells was observed. In conclusion, androstenone and another odorant chemical, which is recognized by OR1I1, may play an important role in stallion testes.
토마토의 착과와 수확량은 여름철 비닐하우스내 고온스트레스로 인하여 감소하게 된다. 본 연구는 여름철 화천지역에 위치한 비닐하우스에서 지베렐린(GA3)과 2,4-Dichlorophenoxy Acetic Acid(2,4-D) 처리가 토마토의 수확량, 착과율, 착과 후 과실품질에 미치는 영향을 알아보기 위해 ‘Adoration‘ 품종을 이용하여 실험하였다. GA3 0-, 5-, 10-, 15mg·L−1와 2,4-D 0-, 5-, 10mg·L−1를 개화 초기에 처리한 후 착과율, 수확량, 과실품질과 관련된 형질을 관찰한 결과, GA3 10mg·L−1처리구에서 대조구에 비해 14.2%의 착과율 증가를 보였다. GA3처리구에서는 수확량, 과중, 상품과실 수에 유의한 차이가 있었다. 2,4-D를 개화기에 처리했을 경우 착과율, 수확량, 상품과의 과중에 영향을 미쳤으며 GA3과 2,4-D를 각각 5mg·L−1 농도로 혼합처리 하였을 때 가장 높은(62.5%) 착과율을 나타내었다. 과실크기와 고형물함량은 GA3처리구에서만 유의성 있는 차이를 보였다. 따라서 여름철 비닐하우스의 고온조건에서 GA3 0mg·L−1처리구와 2,4-D 5mg·L−1를 처리했을 때 착과율이 가장 높아 많은 수확량을 기대할 수 있을 것으로 판단된다.
Immunotherapeutic approaches using agonist antibodies or fusion proteins of immunomodulatory molecules significantly inhibit tumor growth and boost cell-mediated immunity. We isolated mRNA from previously reported 1D4 hybridoma cells and amplified the variable regions of the heavy chain (VH) and light chain (VL) genes using reverse-transcriptase polymerase chain reaction. Using a linker, the amplified sequences for the heavy and light chains were each connected to the sequence for a single polypeptide chain that was designed to be expressed. VL and VH fragments were cloned into the pOptiVEC-TOPO vector containing the human CH2-CH3 fragment. Then, 293T cells were transfected with the 1D4 single-chain Fv-Fc (scFv-Fc) constructs. A549 cells were used for presentation of the 1D4 antigen. Flow cytometry was performed for analysis of the secreted 1D4 scFv-Fc constructs. The DNA sequence of 1D4 scFv-Fc was obtained. The 1D4 scFv-Fc constructs were expressed by the transfected 293T cells and secreted into the culture medium. The immunoreactivity of the secreted scFv-Fc construct was lower than that of the murine 1D4 antibody for A549 cells. A 1D4 scFv-Fc construct for immunotherapy was developed.
Construction industry became huge and complicated as the time went by. It has been so rapidly developed that the construction companies can not survive in the market if the higher technology and scientific approach are not applied. Especially in the field of construction management, it started from the schedule control which simply monitored the work progress, but now it was changed to the integrated construction management covering analysis and forecasting, projected and actual performance management, impact on the project, etc. However, even the integrated construction management has a limit due to the uncertainty arising out of fast track which is a major characteristic of construction industry. So, to minimize the risk of uncertainty, a new concept so-called 4-D CAD system was recently introduced. 4-D CAD system has been applied to design, construction and construction management. The system combines the 3-D CAD system with time management technique that makes it possible to establish the management system with a concept of space, materialize the potential risks, and introduce the life-cycle concept in the whole process covering project initiation, design, construction, completion, commissioning, etc. This paper introduces the 4-D CAD system, reviews the effect and problem arising when applying the system into actual job sites, studies the usage of the system in connection with the conventional construction management system and any improvement, and eventually proposes the method of improving the construction management in domestic projects and of leveling up the construction management technique.
맥작에 있어서 문제 광엽잡초를 2,4-D에 의하여 방제하기 위하여 처리약량, 처리시기, 토성별로 실험을 실시하였던 바 그 결과를 요약하면 다음과 같다. 1) 10a 당 유제 2,4-D amine salt 70cc를 유효분벽 종지기에 처리하였을 때 보리에 거의 약해를 주지 않고 대부분의 광엽잡초의 방제가 가능하였다. 2) 2,4-D의 최적처리시기는 유효분벽 종지기이며, 이보다도 빠르거나 늦게 될 때에는 약해를 내어 수량감소를 가져왔다. 3) 보리의 내성이 가장 강한 시기에 최적약량처리가 될 때에는 토성에 환계없이 2,4-D의 적용이 가능함을 시사하였다.
This study was conducted to develop a predictive model for the growth of Escherichia coli strain RC-4-D isolated from red kohlrabi sprout seeds. We collected E. coli kinetic growth data during red kohlrabi seed sprouting under isothermal conditions (10, 15, 20, 25, and 30°C). Baranyi model was used as a primary order model for growth data. The maximum growth rate (μmax) and lag-phase duration (LPD) for each temperature (except for 10°C LPD) were determined. Three kinds of secondary models (suboptimal Ratkowsky square-root, Huang model, and Arrhenius-type model) were compared to elucidate the influence of temperature on E. coli growth rate. The model performance measures for three secondary models showed that the suboptimal Huang square-root model was more suitable in the accuracy (1.223) and the suboptimal Ratkowsky square-root model was less in the bias (0.999), respectively. Among three secondary order model used in this study, the suboptimal Ratkowsky square-root model showed best fit for the secondary model for describing the effect of temperature. This model can be utilized to predict E. coli behavior in red kohlrabi sprout production and to conduct microbial risk assessments.
The results from air-coupled impact-echo(IE) tests into concrete slab should be interpreted and represented so that field engineers can effectively check the condition of the structure. To improve these issues, IE data in the form of “4-D spectrum plot” can be utilized to identify the information of concrete defects effectively. The concept of the 4-D plot is introduced, and the effects of image parameters (e.g. frequency range, transparency index) are experimentally investigated in this study.
Sorption of chlorinated pesticides such as 2,4-dichlorophenoxyacetic acid (2,4-D) and atrazine onto natural clays (montmorillonite and zeolite) modified with cationic surfactant, hexadecyltrimethyl-ammonium (HDTMA) and a natural soil was investigated using batch adsorbers. The clays were transformed from hydrophilic to hydrophobic by the cation exchange between clay surface and HDTMA up to 100% of the cation exchange capacity (CEC). Physicochemical characteristics of the sorbents such as pH, PZC (point of zero charge), organic carbon content (foc), fourier transform infrared spectroscopy (FT-IR), differential thermogravimetric analysis (DTGA) and X-ray diffraction (XRD) were analyzed. Sorption isotherm models such as Freundlich and Langmuir were fitted to the experimental data, resulting Langmuir model (R2 > 0.986) was fitted better than Freundlich model (R2 > 0.973). Sorption capacity (Q0) for 2,4-D and atrazine was in the order of HDTMA-montmorillonite > HDTMA-zeolite > natural soil corresponding to the increase in organic carbon content (foc). The sorption of the pesticides was also affected by pH. The sorption of 2,4-D decreased with the increase in pH, whereas that of atrazine was not changed. This indicated that the sorption capacity (Q0) of 2,4-D and atrazine was not affected by the solution pH because they exist as anionic (deprotonated) forms at pH above pKa. The results indicate that organoclay has a promising potential to reduce chlorinated pesticides in the effluent from golf courses.
Callus cultures from leaf explants of Gypsophila paniculata L. cv. 'Bristol Fairy' have been tested their growth and morphogenic capacity on Murashige and Skoog medium supplemented with 0.l, 0.5, 1 and 3 mg/L 2,4-D. The frequency of callus formation ranged from 43.3% to 100%. The optimal 2,4-D concentration for promoting callus formation and growth was 0.5 to 3 ㎎/L. 4.2∼ 5.6% of adventitious roots were obtained with the use of 0.1 and 0.5 mg/L 2,4-D. Calli grown well on 1.0 mg/L 2,4-D was the heaviest among the calli grown in various concentrations.
Embryogenic callus cultures of Korean native Seosanjong of ginger(Zingiber of officinale Rosc.) were induced through stem explants taken from in vitro shoot-tip cultures. Among the four concentrations of 2,4-D tested in Murashige and Skoog medium, 0.5 and 1 mg/L of 2,4-D was most effective in inducing embryogenic callus. Leaf explants did not express any new morphogenetic response in all 2,4-D concentrations tested. Plantlets transferred to hormone-free MS medium were developed and successfully acclimatized under greenhouse.
2, 4-D의 경엽처리가 인삼의 지상부 생육 및 광합성능력과 식물체의 Ethylene gas 발생등의 생리적특성에에 미치는 영향을 구명하기 위하여 본 실험을 수행하였던 바 그 결과를 요약하면 다음 과 같다. 1) 표준약량의 3배농도 2, 4-D 경엽처리시에도 엽장, 엽폭, 경장 및 경직경등 지상부 생육은 무처리와 전혀 유의차를 나타내지 않았으며 별다른 생육이상현상도 나타내지 않았다 2) 무처리구에 비해 2, 4-D의 경엽처리시 줄기에 대한 엽병의 각은 현저히 커졌으며 2, 4-D 처리농도가 증가될 수록 엽병각은 거의 직선적인 증가경향을 나타내었다 3) 2, 4-D의 경엽처리에 의해 인삼잎의 광합성능력은 현저히 저하되었으며 그 정도는 2, 4-D 처리농도를 증가함에 따라 현저히 크게 나타났다. 4) 2, 4-D의 경엽처리에 의한 인삼잎의 광합성저해현상은 표준 및 2배 농도 처리구에서는 처리후 3일에 정상으로 회복되었으나 3배 농도구에서는 처리후 12일 이후에 거의 회복단계가 되었다. 5) 표준 및 2배 농도의 2, 4-D 처리구에서는 무처리구와 같이 전혀 Ethylene gas의 발생을 측정할 수 없었으며 3배 농도 처리구에서만 미량의 Ethylene gas가 정량되었으나 이는 표준약량의 2, 4-D를 처리한 중에서 발생된 Ethylene gas 량의 1/20에 불과하였다.