• Journal of Animal Science and Technology
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• 제63권2호
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• pp.281-294
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• 2021

Although somatic cell nuclear transfer (SCNT) is frequently employed to produce cloned animals in laboratories, this technique is expensive and inefficient. Therefore, the handmade cloning (HMC) technique has been suggested to simplify and advance the cloning process, however, HMC wastes many oocytes and leads to mitochondrial heteroplasmy. To solve these problems, we propose a modified handmade cloning (mHMC) technique that uses simple laboratory equipment, i.e., a Pasteur pipette and an alcohol lamp, applying it to porcine embryo cloning. To validate the application of mHMC to pig cloning, embryos produced through SCNT and mHMC are compared using multiple methods, such as enucleation efficiency, oxidative stress, embryo developmental competence, and gene expression. The results show no significant differences between techniques except in the enucleation efficiency. The 8-cell and 16-cell embryo developmental competence and Oct4 expression levels exhibit significant differences. However, the blastocyst rate is not significantly different between mHMC and SCNT. This study verifies that cloned embryos derived from the two techniques exhibit similar generation and developmental competence. Thus, we suggest that mHMC could replace SCNT for simpler and cheaper porcine cloning.

• Journal of Yeungnam Medical Science
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• 제4권1호
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• pp.1-15
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• 1987

Magnetic Resonance (M.R.) is rapidly emerging technique that provides high quality images and potentially provides much more diagnostic information than do conventional imaging modalities. M.R.I. is conceptually quite different from currently used imaging methods. The complex nature of M.R.I. allows a great deal of flexibility in image product ion and available information, and key points are as follows. 1. M.R.I. offers a non-invasive technique with which to gene rate in vivo human images without ionizing radiation and with no known adverse biological effects. 2. Imaging mechanism of M.R.I. is quite different from conventional imaging modality and for more accurate diagnostic application, It is necessary for physician to understand imaging mechanism of M.R.I. 3. M.R. makes available basic chemical parameters that may provide to be useful for diagnostic medical imaging and more specific pathophysiologic information which are not available by alternate techniques. 4. M.R. can be produced by number of different methods. This flexibility allows the imaging technique to be applicated for particular clinical purpose. Multiplanar and three dimensional imaging may extend the imaging process beyond the single section available with current CT. 5. Future directions include efforts to; a. Further development of hard ware b. More fasternning scan time c. Respiratory and cardiac gated imaging d. Imaging of additional nuclei except hydrogen e. Further development of contrast media f. M.R. in vivo spectroscopy g. Real time M.R. imaging.

• ETRI Journal
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• 제28권3호
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• pp.355-363
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• 2006

This paper presents a low-cost RF parameter estimation technique using a new RF built-in self-test (BIST) circuit and efficient DC measurement for 4.5 to 5.5 GHz low noise amplifiers (LNAs). The BIST circuit measures gain, noise figure, input impedance, and input return loss for an LNA. The BIST circuit is designed using $0.18\;{\mu}m$ SiGe technology. The test technique utilizes input impedance matching and output DC voltage measurements. The technique is simple and inexpensive.

• Advances in materials Research
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• 제2권4호
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• pp.195-208
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• 2013

A comprehensive theory of the spin coating technique has been reviewed and the basic principles and parameters controlling the process are clearly highlighted, which include spin speed, spin time, acceleration and fume exhaust. The process generally involves four stages: a dispense stage, substrate acceleration stage, a stage of substrate spinning at a constant rate and fluid viscous forces dominate fluid thinning behaviour and a stage of substrate spinning at a constant rate and solvent evaporation dominates the coating thinning behaviour. The study also considered some common thin film defects associated with this technique, which include comet, striation, chucks marks environmental sensitivity and edge effect and possible remedies.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1375-1382
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• 2007

A column preconcentration method with pulverized Amberlite XAD-4 loaded with bismuthiol I (BI) has been developed for the determination of trace Cd(II) and Cu(II) in various real samples by flame atomic absorption spectrophotometry. Various experimental conditions, such as the size of XAD-4, adsorption flow rate, amount of bismuthiol I, stirring time for adsorbing bismuthiol I on XAD-4, pH of sample solution, amount of XAD-4- BI, desorption solvent, and desorption flow rate, were optimized. Also, the adsorption capacity and the adsorption rate of Cd(II) and Cu(II) on XAD-4-BI were investigated. The interfering effects of various concomitant ions were investigated, Bi(III), Sn(II) and Fe(III) were found to affect the determination. But the interference by these ions was completely eliminated by adjusting the amount of XAD-4-BI resin to 0.70 g, although the adsorption flow rate was slower. For Cd(II) our proposed technique obtained a dynamic range of 0.5-40 ng mL-1, a correlation coefficient (R2) of 0.9913, and a detection limit of 0.3 ng mL-1. For Cu(II), the corresponding values were 2.0-120 ng mL-1, 0.9921 and 1.02 ng mL-1. To validate this proposed technique, the aqueous samples (stream water, reservoir water, tap water and wastewater), the diluted brass sample and the plastic sample, as real samples, were used. Recovery yields of 91-103% were obtained. These measured data were not different from ICP-MS data at 95% confidence level. Our proposed method was also validated using rice flour CRM (normal, fortified) samples. From the results of our experiment, we found that the technique we present here can be applied to the determination of Cd(II) and Cu(II) in various real samples.

• Journal of Digestive Cancer Research
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• 제4권2호
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• pp.113-121
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• 2016

Background: We evaluated technique of hepatic resections using suprahilar-extrafascial dissection of Glissonean pedicle with vascular stapling device for pedicle transection with intent to minimize operative time and blood loss. Methods: We analyzed the clinical records of 326 patients who underwent anatomic liver resection by suprahilar-extrafascial pedicle isolation with vascular stapling division technique. Results: The minor liver resections were associated with significantly shorter surgery duration (105.1±21.1 vs. 225.6±75.6) and transection time (40.1±14.5 vs. 96.3±55.2) than major hepatectomies (p<0.0001 for all). The mean blood loss was 350.8±100.5 mL in minor resection and 485.4±250.2 mL in major resection (p=0.001). The mean blood transfusion requirement was 400.8±109.5 mL for minor resections and 550.9±100.0 mL for major hepatectomy (p=0.072). There was no significant difference in morbidity and mortality between groups (p=0.980; p=0.945). Major as well as minor liver resection were oncology superior with no significant difference in the 5-year overall survival rates. Conclusion: Suprahilar-extrafascial dissection of Glissonean pedicle represents an effective and safe technique of liver resection. Presented approach allows early and easy ischemic delineation of appropriate liver territory to be removed with selective inflow vascular control. It is not time consuming and it is very useful in re-resection, as well as oncological reasonable.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제42권
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• pp.5.1-5.9
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• 2020

Immunomodulation is a technique for the modulation of immune responses against graft material to improve surgical success rates. The main target cell for the immunomodulation is a macrophage because it is the reaction site of the graft and controls the healing process. Macrophages can be classified into M1 and M2 types. Most immunomodulation techniques focus on the rapid differentiation of M2-type macrophage. An M2 inducer, 4-hexylresorcinol, has been recently identified and is used for bone grafts and dental implant coatings.

• The Journal of Advanced Prosthodontics
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• 제6권4호
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• pp.253-258
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• 2014

PURPOSE. To compare marginal and internal gaps of zirconia substructure of single crowns with those of three-unit fixed dental prostheses. MATERIALS AND METHODS. Standardized Co-Cr alloy simulated second premolar and second molar abutments were fabricated and subsequently duplicated into type-III dental stone for working casts. After that, all zirconia substructures were made using $Lava^{TM}$ system. Marginal and internal gaps were measured in 2 planes (mesial-distal plane and buccal-palatal plane) at 5 locations: marginal opening (MO), chamfer area (CA), axial wall (AW), cusp tip (CT) and mid-occlusal (OA) using Replica technique. RESULTS. There were significant differences between gaps at all locations. The $mean{\pm}SD$ of marginal gap in premolar was $43.6{\pm}0.4{\mu}m$ and $46.5{\pm}0.5{\mu}m$ for single crown and 3-unit bridge substructure respectively. For molar substructure the $mean{\pm}SD$ of marginal gap was $48.5{\pm}0.4{\mu}m$ and $52.6{\pm}0.4{\mu}m$ for single crown and 3-unit bridge respectively. The largest gaps were found at the occlusal area, which was $150.5{\pm}0.5{\mu}m$ and $154.5{\pm}0.4{\mu}m$ for single and 3-unit bridge premolar substructures respectively and $146.5{\pm}0.4{\mu}m$ and $211.5{\pm}0.4{\mu}m$ for single and 3-unit bridge molar substructure respectively. CONCLUSION. Independent-samples t-test showed significant differences of gap in zirconia substructure between single crowns and three-unit bridge (P<.001). Therefore, the span length has the effect on the fit of zirconia substructure that is fabricated using CAD/CAM technique especially at the occlusal area.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1253-1253
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• 2006

• Fisheries and Aquatic Sciences
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• 제25권10호
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• pp.525-536
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• 2022

Photosynthetic bacteria (PSB) attract considerable interest as useful microorganisms; nevertheless, a generalized culture technique has not been previously reported owing to difficulty in their cultivation. Therefore, a simple culture technique suitable for public use was investigated. Among the PSB tested, the strain Rhodobacter azotoformans EBN-7 was the most suitable for scale-up production because it showed the highest specific growth rate (0.20 h^-1) on basal medium. In scale-up cultivation (500 L), R. azotoformans EBN-7 showed 4.50 × 10¹⁰ colony-forming units mL^-1 (number of viable cells), dry cell weight of 26.8 g/L, and a specific growth rate of 0.15 h^-1. Cultivation using this final culture broth (as seed culture) in a 15 L simple reactor was successful, with maintenance of cell activity evident. For use as seed culture, the maximum allowable preservation period of R. azotoformans EBN-7 at 4℃ was 3 months. When R. azotoformans EBN-7 cultivated in a simple technique was applied to shrimp aquaculture water, NH₄⁺-N was reduced from 0.61 mg/L to 0.24 mg/L (by 60.7%) in 4 days in comparison with the control. Thus, this simple culture technique using R. azotoformans EBN-7 has the potential for a good removal efficiency of NH₄⁺-N, making seed culture easier and suitable for public use.