• Journal of Korean Neurosurgical Society
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• v.61 no.3
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• pp.415-423
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• 2018

Objective : To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis. Methods : We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest. Results : There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively). Conclusion : When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.

• Korean Circulation Journal
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• v.52 no.1
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• pp.1-33
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• 2022

In primary prevention for cardiovascular diseases, there are significant barriers to adherence including freedom from symptoms, long latency for therapeutic benefits, life-long duration of treatment, and need for combined lifestyle changes. However, to implement more systematic approaches, the focus on adherence improvement needs to be shifted away from patient factors to the effects of the treatment team and healthcare system. In addition to conventional educational approaches, more patient-oriented approaches such as patient-centered clinical communication skills, counseling using motivational strategies, decision-making by patient empowerment, and a multi-disciplinary team approach should be developed and implemented. Patients should be involved in a program of self-monitoring, self-management, and active counseling. Because most effective interventions on adherence improvement demand greater resources, the health care system and educational or training system of physicians and healthcare staff need to be supported for systematic improvement.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.1
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• pp.1-9
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• 2009

As many new drug substances contained various aromatic rings and fluorine attached to an electron rich aromatic ring or on the meta-position, a strategy towards improvement in aromatic fluorination of these compounds is highly desirable. The introduction of fluorine-18 onto aromatic rings showed in the limited condition containing electron withdrawing group (EWG) on the para- or ortho-position to get reasonable radiochemical yield so far. No-carrier added (NCA) [$^{18}F$]fluoroarene syntheses by iodonium salts recently reported that has the potential to greatly increase the yield in systems or positions that normally not reactive enough to give sufficient yields in simple model reaction. This review describes the methodological approach towards effective aromatic fluorination by diaryliodonium salts and future prospects in an application of novel PET radiotracer.

• The Journal of Korea Robotics Society
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• v.9 no.4
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• pp.250-257
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• 2014

In this paper, a new mobile robot, so called a rollerbot, is presented, which has single body and rugby-ball shaped roller wheel. A rollerbot has single point contact on ground and low energy consumption in motion because of the reduced friction. By changing center of mass using a balancing weight, a rollerbot is able to get steering force. The vertical position of mass center of the rollerbot in this paper is designed to lie inside radius of the roller wheel, so that to have stable equilibrium position. Thus, the posture and the steering control of the rollerbot can be easily done by changing the center of mass. Kinematics of the rollerbot is derived by transformation of differential motion in this paper.

• 대한임상약리학회:학술대회논문집
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• 1999.12a
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• pp.34-34
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• 1999

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.3
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• pp.360-369
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• 2012

The causes of showing different subthreshold slopes (SS) in programmed and erased states for two different charge trap flash (CTF) memory devices, SONOS type flash memory with gate-all-around (GAA) structure and TANOS type NAND flash memory with planar structure were investigated. To analyze the difference in SSs, TCAD simulation and low-frequency noise (LFN) measurement were fulfilled. The device simulation was performed to compare SSs considering the gate electric field effect to the channel and to check the localized trapped charge distribution effect in nitride layer while the comparison of noise power spectrum was carried out to inspect the generation of interface traps ($N_{IT}$). When each cell in the measured two memory devices is erased, the normalized LFN power is increased by one order of magnitude, which is attributed to the generation of $N_{IT}$ originated by the movement of hydrogen species ($h^*$) from the interface. As a result, the SS is degraded for the GAA SONOS memory device when erased where the $N_{IT}$ generation is a prominent factor. However, the TANOS memory cell is relatively immune to the SS degradation effect induced by the generated $N_{IT}$.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.440-447
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• 2013

PURPOSE. Template-guided implant therapy has developed hand-in-hand with computed tomography (CT) to improve the accuracy of implant surgery and future prosthodontic treatment. In our present study, the accuracy and causative factors for computer-assisted implant surgery were assessed to further validate the stable clinical application of this technique. MATERIALS AND METHODS. A total of 102 implants in 48 patients were included in this study. Implant surgery was performed with a stereolithographic template. Pre- and post-operative CTs were used to compare the planned and placed implants. Accuracy and related factors were statistically analyzed with the Spearman correlation method and the linear mixed model. Differences were considered to be statistically significant at $P{\leq}.05$. RESULTS. The mean errors of computer-assisted implant surgery were 1.09 mm at the coronal center, 1.56 mm at the apical center, and the axis deviation was $3.80^{\circ}$. The coronal and apical errors of the implants were found to be strongly correlated. The errors developed at the coronal center were magnified at the apical center by the fixture length. The case of anterior edentulous area and longer fixtures affected the accuracy of the implant template. CONCLUSION. The control of errors at the coronal center and stabilization of the anterior part of the template are needed for safe implant surgery and future prosthodontic treatment.

• Journal of Korean Society of Rural Planning
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• v.14 no.3
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• pp.75-87
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• 2008

Changes in society organization of rural villages in our country are caused by aging society and lessening of economic activity population aggravates the economy of rural villages. With this, it joins in with the aging of village community center, the representative center space of the rural village and therefore, it is a point of view where the change is necessary in the size and the side of function. The research which it sees is made on-the-spot inspection and literature investigation compensate in behalf of 25 administrative village community centers led in the object by grasping present status and drew up the layout sketches and plane surface degrees of the village community centers. By referring to the photographs and the topographical maps taken in the spot, it was able to divide the village community centers into side of arrangement, side of plane surface and side of form and managed to seize the characters, problems and improvable directions of each of them. The research result could be used as a guidable provision and be applied in the fundamental research in developing model of village community centers during space planning in the future.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.417-422
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• 1997

Recombinant Bacillus subtilis LKS88[pASA240] containing the amylase gene from Streptomyces albus KSM-35 was exploited in fed-batch cultivation for mass production of maltotetraose-producing amylase. The effects of dissolved oxygen, additional organic nutrients (peptone and yeast extract) and mixed carbon sources (glucose plus soluble starch) on amylase production were examined in fed-batch operations in an effort to determine the optimum conditions for a maximum amylase productivity. Under the optimum conditions, maximum amylase activity was about 4.2 times higher than that obtained in batch cultivations, indicating that mass production of maltotetraose-producing amylase could be accomplished in fed-batch cultivation of the recombinant B. subtilis strain.

• Journal of Chest Surgery
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• v.55 no.5
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• pp.388-396
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• 2022

Background: In this study, we present recent trends in heart valve surgery in Korea through analyses of data from the Korea Heart Valve Surgery Registry (KHVSR). Methods: We enrolled 8,981 patients who were registered in the KHVSR from 2017 to 2020. Yearly trends in patients' baseline characteristics, surgical profiles, and early mortality rates were explored. The observed/expected mortality ratio (O/E ratio), calculated from the actual mortality in the KHVSR and the predicted mortality estimated using the EuroSCORE II, was also analyzed. Results: The proportion of aortic valve surgery significantly increased from 56.8% in 2017 to 60.3% in 2020. The proportion of all combined procedures and minimally invasive surgery significantly increased over the 4-year study period. The operative mortality rate was 2.9% in the entire cohort, while mitral valve repair showed the lowest mortality risk (0.9%). The mortality rates of isolated aortic valve replacement (AVR) significantly decreased from 2.1% in 2017 to 0.8% in 2020 (p=0.016). Overall, the O/E ratio was 0.784 (95% confidence interval [CI], 0.677-0.902) demonstrating significantly lower actual mortality risks than expected based on the EuroSCORE II. In particular, the O/E ratios were as low as 0.364 (95% CI, 0.208-0.591) for isolated AVR. Conclusion: The recent data from the KHVSR showed increasing trends for complex procedures and minimally invasive surgery in heart valve surgery in Korea, and demonstrated remarkably low risks of operative mortality.